A Phase 0/1 Pharmacokinetic and Pharmacodynamics and Safety and Tolerability Study of Letrozole in Combination with Standard Therapy in Recurrent High-Grade Gliomas

PURPOSE

High grade gliomas (HGGs) carry a poor prognosis, with glioblastoma accounting for almost 50% of primary brain malignancies in the elderly. Unfortunately, despite the use of multiple treatment modalities, the prognosis remains poor in this population. Our pre-clinical studies suggest that the presence of aromatase expression, encoded by CYP19A1, is significantly upregulated in HGGs. Remarkably, we find that letrozole (LTZ), an FDA approved aromatase inhibitor, has marked activity against HGGs.

METHODS

We conducted a phase 0/I single center clinical trial (NCT03122197) to assess the tumoral availability, pharmacokinetics (PK), safety and tolerability of LTZ in recurrent HGG patients. Planned dose cohorts included 2.5, 5, 10, 12.5, 15, 17.5 and 20 mg of LTZ administered daily pre- and post-surgery or biopsy. Tumor samples were assayed for LTZ content and relevant biomarkers. The Recommended Phase 2 Dose (R2PD) was determined as the dose that resulted in predicted steady state tumoral extracellular fluid (ECF) (Css,ecf) > 2 µM and did not result in ≥ 33% dose limiting adverse events (AEs) assessed using CTCAE v5.0.

RESULTS

Twenty-one patients were enrolled. Common LTZ related AEs included fatigue, nausea, musculoskeletal, anxiety and dysphoric mood. No DLTs were observed. The 15 mg dose achieved a Css,ecf of 3.6 +/- 0.59 µM. LTZ caused dose-dependent inhibition of estradiol synthesis and modulated DNA damage pathways in tumor tissues as evident using RNA-seq analysis.

CONCLUSION

Based on safety, brain tumoral PK, and mechanistic data, 15 mg daily is identified as the RP2D for future trials.

Proton Treatment Suppresses Exosome Production in Head and Neck Squamous Cell Carcinoma

Proton therapy (PT) is emerging as an effective and less toxic alternative to conventional X-ray-based photon therapy (XRT) for patients with advanced head and neck squamous cell carcinomas (HNSCCs) owing to its clustered dose deposition dosimetric characteristics. For optimal efficacy, cancer therapies, including PT, must elicit a robust anti-tumor response by effector and cytotoxic immune cells in the tumor microenvironment (TME). While tumor-derived exosomes contribute to immune cell suppression in the TME, information on the effects of PT on exosomes and anti-tumor immune responses in HNSCC is not known. In this study, we generated primary HNSCC cells from tumors resected from HNSCC patients, irradiated them with 5 Gy PT or XRT, and isolated exosomes from cell culture supernatants. HNSCC cells exposed to PT produced 75% fewer exosomes than XRT- and non-irradiated HNSCC cells. This effect persisted in proton-irradiated cells for up to five days. Furthermore, we observed that exosomes from proton-irradiated cells were identical in morphology and immunosuppressive effects (suppression of IFN-γ release by peripheral blood mononuclear cells) to those of photon-irradiated cells. Our results suggest that PT limits the suppressive effect of exosomes on cancer immune surveillance by reducing the production of exosomes that can inhibit immune cell function.

The impact of cancer metastases on COVID-19 outcomes: A COVID-19 and Cancer Consortium registry-based retrospective cohort study

BACKGROUND

COVID-19 can have a particularly detrimental effect on patients with cancer, but no studies to date have examined if the presence, or site, of metastatic cancer is related to COVID-19 outcomes.

METHODS

Using the COVID-19 and Cancer Consortium (CCC19) registry, the authors identified 10,065 patients with COVID-19 and cancer (2325 with and 7740 without metastasis at the time of COVID-19 diagnosis). The primary ordinal outcome was COVID-19 severity: not hospitalized, hospitalized but did not receive supplemental O2 , hospitalized and received supplemental O2 , admitted to an intensive care unit, received mechanical ventilation, or died from any cause. The authors used ordinal logistic regression models to compare COVID-19 severity by presence and specific site of metastatic cancer. They used logistic regression models to assess 30-day all-cause mortality.

RESULTS

Compared to patients without metastasis, patients with metastases have increased hospitalization rates (59% vs. 49%) and higher 30 day mortality (18% vs. 9%). Patients with metastasis to bone, lung, liver, lymph nodes, and brain have significantly higher COVID-19 severity (adjusted odds ratios [ORs], 1.38, 1.59, 1.38, 1.00, and 2.21) compared to patients without metastases at those sites. Patients with metastasis to the lung have significantly higher odds of 30-day mortality (adjusted OR, 1.53; 95% confidence interval, 1.17-2.00) when adjusting for COVID-19 severity.

CONCLUSIONS

Patients with metastatic cancer, especially with metastasis to the brain, are more likely to have severe outcomes after COVID-19 whereas patients with metastasis to the lung, compared to patients with cancer metastasis to other sites, have the highest 30-day mortality after COVID-19.

Systemic Anticancer Therapy and Thromboembolic Outcomes in Hospitalized Patients With Cancer and COVID-19

Importance

Systematic data on the association between anticancer therapies and thromboembolic events (TEEs) in patients with COVID-19 are lacking.

Objective

To assess the association between anticancer therapy exposure within 3 months prior to COVID-19 and TEEs following COVID-19 diagnosis in patients with cancer.

Design, Setting, and Participants

This registry-based retrospective cohort study included patients who were hospitalized and had active cancer and laboratory-confirmed SARS-CoV-2 infection. Data were accrued from March 2020 to December 2021 and analyzed from December 2021 to October 2022.

Exposure

Treatments of interest (TOIs) (endocrine therapy, vascular endothelial growth factor inhibitors/tyrosine kinase inhibitors [VEGFis/TKIs], immunomodulators [IMiDs], immune checkpoint inhibitors [ICIs], chemotherapy) vs reference (no systemic therapy) in 3 months prior to COVID-19.

Main Outcomes and Measures

Main outcomes were (1) venous thromboembolism (VTE) and (2) arterial thromboembolism (ATE). Secondary outcome was severity of COVID-19 (rates of intensive care unit admission, mechanical ventilation, 30-day all-cause mortality following TEEs in TOI vs reference group) at 30-day follow-up.

Results

Of 4988 hospitalized patients with cancer (median [IQR] age, 69 [59-78] years; 2608 [52%] male), 1869 had received 1 or more TOIs. Incidence of VTE was higher in all TOI groups: endocrine therapy, 7%; VEGFis/TKIs, 10%; IMiDs, 8%; ICIs, 12%; and chemotherapy, 10%, compared with patients not receiving systemic therapies (6%). In multivariable log-binomial regression analyses, relative risk of VTE (adjusted risk ratio [aRR], 1.33; 95% CI, 1.04-1.69) but not ATE (aRR, 0.81; 95% CI, 0.56-1.16) was significantly higher in those exposed to all TOIs pooled together vs those with no exposure. Among individual drugs, ICIs were significantly associated with VTE (aRR, 1.45; 95% CI, 1.01-2.07). Also noted were significant associations between VTE and active and progressing cancer (aRR, 1.43; 95% CI, 1.01-2.03), history of VTE (aRR, 3.10; 95% CI, 2.38-4.04), and high-risk site of cancer (aRR, 1.42; 95% CI, 1.14-1.75). Black patients had a higher risk of TEEs (aRR, 1.24; 95% CI, 1.03-1.50) than White patients. Patients with TEEs had high intensive care unit admission (46%) and mechanical ventilation (31%) rates. Relative risk of death in patients with TEEs was higher in those exposed to TOIs vs not (aRR, 1.12; 95% CI, 0.91-1.38) and was significantly associated with poor performance status (aRR, 1.77; 95% CI, 1.30-2.40) and active/progressing cancer (aRR, 1.55; 95% CI, 1.13-2.13).

Conclusions and Relevance

In this cohort study, relative risk of developing VTE was high among patients receiving TOIs and varied by the type of therapy, underlying risk factors, and demographics, such as race and ethnicity. These findings highlight the need for close monitoring and perhaps personalized thromboprophylaxis to prevent morbidity and mortality associated with COVID-19-related thromboembolism in patients with cancer.

Durvalumab plus Cetuximab in Patients with Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: An Open-label, Nonrandomized, Phase II Clinical Trial

PURPOSE

The efficacy of cetuximab is poor in metastatic head and neck squamous cell carcinoma (HNSCC). Cetuximab initiates natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity, with resultant recruitment of immune cells and suppression of antitumor immunity. We hypothesized that adding an immune-checkpoint inhibitor (ICI) could overcome this and lead to an enhanced antitumor response.

PATIENTS AND METHODS

A phase II study of cetuximab and durvalumab in metastatic HNSCC was conducted. Eligible patients had measurable disease. Patients who had received both cetuximab and an ICI were excluded. The primary endpoint was objective response rate (ORR) by RECIST 1.1 at 6 months.

RESULTS

As of April 2022, 35 patients enrolled, of whom 33 received at least 1 dose of durvalumab and were included in the response analysis. Eleven patients (33%) had received prior platinum-based chemotherapy, 10 an ICI (30%), and 1 patient (3%) cetuximab. ORR was 39% (13/33) with a median duration of response of 8.6 months [95% confidence interval (CI): 6.5-16.8]. Median progression-free and overall survivals were 5.8 months (95% CI: 3.7-14.1) and 9.6 months (95% CI: 4.8-16.3), respectively. There were 16 grade 3 treatment-related adverse events (TRAE) and one grade 4 TRAE, with no treatment-related deaths. Overall and progression-free survival did not correlate with PD-L1 status. NK cell cytotoxic activity was increased by cetuximab and further increased with the addition of durvalumab in responders.

CONCLUSIONS

The combination of cetuximab and durvalumab demonstrated durable activity with a tolerable safety profile in metastatic HNSCC and warrants further investigation.

Single cell transcriptomic analysis of HPV16-infected epithelium identifies a keratinocyte subpopulation implicated in cancer

Persistent HPV16 infection is a major cause of the global cancer burden. The viral life cycle is dependent on the differentiation program of stratified squamous epithelium, but the landscape of keratinocyte subpopulations which support distinct phases of the viral life cycle has yet to be elucidated. Here, single cell RNA sequencing of HPV16 infected compared to uninfected organoids identifies twelve distinct keratinocyte populations, with a subset mapped to reconstruct their respective 3D geography in stratified squamous epithelium. Instead of conventional terminally differentiated cells, an HPV-reprogrammed keratinocyte subpopulation (HIDDEN cells) forms the surface compartment and requires overexpression of the ELF3/ESE-1 transcription factor. HIDDEN cells are detected throughout stages of human carcinogenesis including primary human cervical intraepithelial neoplasias and HPV positive head and neck cancers, and a possible role in promoting viral carcinogenesis is supported by TCGA analyses. Single cell transcriptome information on HPV-infected versus uninfected epithelium will enable broader studies of the role of individual keratinocyte subpopulations in tumor virus infection and cancer evolution.

A phase Ib trial of mivavotinib (TAK-659), a dual SYK/FLT3 inhibitor, in patients with relapsed/refractory acute myeloid leukemia

Mivavotinib (TAK-659) is an investigational type 1 tyrosine kinase inhibitor with dual activity against spleen tyrosine kinase (SYK) and FMS-like tyrosine kinase 3 (FLT3). We conducted a phase Ib study to investigate the safety, tolerability, and efficacy of mivavotinib in patients with refractory and/or relapsed (R/R) acute myeloid leukemia (AML). Both daily (QD) and twice daily (BID) dosing regimens were evaluated. A total of 43 patients were enrolled, and there were 5 complete responses (4 with incomplete count recovery). In the QD dosing regimen, the maximum tolerated dose (MTD) was not reached up to 160 mg QD per protocol; 140 mg QD was identified as the recommended phase II dose. In the BID dosing regimen, the MTD was 60 mg BID. Thirty patients (70%) experienced a bleeding event on study; the majority were grades 1 or 2, were resolved without mivavotinib modification, and were not considered related to study treatment. Eleven patients (26%) experienced grade ≥3 bleeding events, which were observed most frequently with the 80 mg BID dose. We conducted platelet aggregation studies to investigate the potential role of mivavotinib-mediated SYK inhibition on platelet function. The bleeding events observed may have been the result of several confounding factors, including AML disease status, associated thrombocytopenia, and high doses of mivavotinib. Overall, these findings indicate that the activity of mivavotinib in R/R AML is modest. Furthermore, any future clinical investigation of this agent should be undertaken with caution, particularly in thrombocytopenic patients, due to the potential bleeding risk of SYK inhibition. ClinicalTrials.gov: NCT02323113.

Breakthrough SARS-CoV-2 infections among patients with cancer following two and three doses of COVID-19 mRNA vaccines: a retrospective observational study from the COVID-19 and Cancer Consortium

Background

Breakthrough SARS-CoV-2 infections following vaccination against COVID-19 are of international concern. Patients with cancer have been observed to have worse outcomes associated with COVID-19 during the pandemic. We sought to evaluate the clinical characteristics and outcomes of patients with cancer who developed breakthrough SARS-CoV-2 infections after 2 or 3 doses of mRNA vaccines.

Methods

We evaluated the clinical characteristics of patients with cancer who developed breakthrough infections using data from the multi-institutional COVID-19 and Cancer Consortium (CCC19; NCT04354701). Analysis was restricted to patients with laboratory-confirmed SARS-CoV-2 diagnosed in 2021 or 2022, to allow for a contemporary unvaccinated control population; potential differences were evaluated using a multivariable logistic regression model after inverse probability of treatment weighting to adjust for potential baseline confounding variables. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) are reported. The primary endpoint was 30-day mortality, with key secondary endpoints of hospitalization and ICU and/or mechanical ventilation (ICU/MV).

Findings

The analysis included 2486 patients, of which 564 and 385 had received 2 or 3 doses of an mRNA vaccine prior to infection, respectively. Hematologic malignancies and recent receipt of systemic anti-neoplastic therapy were more frequent among vaccinated patients. Vaccination was associated with improved outcomes: in the primary analysis, 2 doses (aOR: 0.62, 95% CI: 0.44-0.88) and 3 doses (aOR: 0.20, 95% CI: 0.11-0.36) were associated with decreased 30-day mortality. There were similar findings for the key secondary endpoints of ICU/MV (aOR: 0.60, 95% CI: 0.45-0.82 and 0.37, 95% CI: 0.24-0.58) and hospitalization (aOR: 0.60, 95% CI: 0.48-0.75 and 0.35, 95% CI: 0.26-0.46) for 2 and 3 doses, respectively. Importantly, Black patients had higher rates of hospitalization (aOR: 1.47, 95% CI: 1.12-1.92), and Hispanic patients presented with higher rates of ICU/MV (aOR: 1.61, 95% CI: 1.06-2.44).

Interpretation

Vaccination against COVID-19, especially with additional doses, is a fundamental strategy in the prevention of adverse outcomes including death, among patients with cancer.

Funding

This study was partly supported by grants from the National Cancer Institute grant number P30 CA068485 to C-YH, YS, SM, JLW; T32-CA236621 and P30-CA046592 to C.R.F; CTSA 2UL1TR001425-05A1 to TMW-D; ACS/FHI Real-World Data Impact Award, P50 MD017341-01, R21 CA242044-01A1, Susan G. Komen Leadership Grant Hunt to MKA. REDCap is developed and supported by Vanderbilt Institute for Clinical and Translational Research grant support (UL1 TR000445 from NCATS/NIH).

Improving Radiotherapy Response in the Treatment of Head and Neck Cancer

The application of radiotherapy to the treatment of cancer has existed for over 100 years. Although its use has cured many, much work remains to be done to minimize side effects, and in-field tumor recurrences. Resistance of the tumor to a radiation-mediated death remains a complex issue that results in local recurrence and significantly decreases patient survival. Here, we review mechanisms of radioresistance and selective treatment combinations that improve the efficacy of the radiation that is delivered. Further investigation into the underlying mechanisms of radiation resistance is warranted to develop not just novel treatments, but treatments with improved safety profiles relative to current radiosensitizers. This review is written in memory and honor of Dr. Peter Stambrook, an avid scientist and thought leader in the field of DNA damage and carcinogenesis, and a mentor and advocate for countless students and faculty.

Interplay of Immunosuppression and Immunotherapy Among Patients With Cancer and COVID-19

Importance

Cytokine storm due to COVID-19 can cause high morbidity and mortality and may be more common in patients with cancer treated with immunotherapy (IO) due to immune system activation.

Objective

To determine the association of baseline immunosuppression and/or IO-based therapies with COVID-19 severity and cytokine storm in patients with cancer.

Design, Setting, and Participants

This registry-based retrospective cohort study included 12 046 patients reported to the COVID-19 and Cancer Consortium (CCC19) registry from March 2020 to May 2022. The CCC19 registry is a centralized international multi-institutional registry of patients with COVID-19 with a current or past diagnosis of cancer. Records analyzed included patients with active or previous cancer who had a laboratory-confirmed infection with SARS-CoV-2 by polymerase chain reaction and/or serologic findings.

Exposures

Immunosuppression due to therapy; systemic anticancer therapy (IO or non-IO).

Main Outcomes and Measures

The primary outcome was a 5-level ordinal scale of COVID-19 severity: no complications; hospitalized without requiring oxygen; hospitalized and required oxygen; intensive care unit admission and/or mechanical ventilation; death. The secondary outcome was the occurrence of cytokine storm.

Results

The median age of the entire cohort was 65 years (interquartile range [IQR], 54-74) years and 6359 patients were female (52.8%) and 6598 (54.8%) were non-Hispanic White. A total of 599 (5.0%) patients received IO, whereas 4327 (35.9%) received non-IO systemic anticancer therapies, and 7120 (59.1%) did not receive any antineoplastic regimen within 3 months prior to COVID-19 diagnosis. Although no difference in COVID-19 severity and cytokine storm was found in the IO group compared with the untreated group in the total cohort (adjusted odds ratio [aOR], 0.80; 95% CI, 0.56-1.13, and aOR, 0.89; 95% CI, 0.41-1.93, respectively), patients with baseline immunosuppression treated with IO (vs untreated) had worse COVID-19 severity and cytokine storm (aOR, 3.33; 95% CI, 1.38-8.01, and aOR, 4.41; 95% CI, 1.71-11.38, respectively). Patients with immunosuppression receiving non-IO therapies (vs untreated) also had worse COVID-19 severity (aOR, 1.79; 95% CI, 1.36-2.35) and cytokine storm (aOR, 2.32; 95% CI, 1.42-3.79).

Conclusions and Relevance

This cohort study found that in patients with cancer and COVID-19, administration of systemic anticancer therapies, especially IO, in the context of baseline immunosuppression was associated with severe clinical outcomes and the development of cytokine storm.

Trial Registration

ClinicalTrials.gov Identifier: NCT04354701.

Metformin increases natural killer cell functions in head and neck squamous cell carcinoma through CXCL1 inhibition

BACKGROUND

Metformin slows tumor growth and progression in vitro, and in combination with chemoradiotherapy, resulted in high overall survival in patients with head and neck cancer squamous cell carcinoma (HNSCC) in our phase 1 clinical trial (NCT02325401). Metformin is also postulated to activate an antitumor immune response. Here, we investigate immunologic effects of metformin on natural killer (NK) and natural killer T cells, including results from two phase I open-label studies in patients with HNSCC treated with metformin (NCT02325401, NCT02083692).

METHODS

Peripheral blood was collected before and after metformin treatment or from newly diagnosed patients with HNSCC. Peripheral immune cell phenotypes were evaluated using flow cytometry, cytokine expression by ELISA and/or IsoLight, and NK cell-mediated cytotoxicity was determined with a flow-based NK cell cytotoxicity assay (NKCA). Patient tumor immune infiltration before and after metformin treatment was analyzed with immunofluorescence. NK cells were treated with either vehicle or metformin and analyzed by RNA sequencing (RNA-seq). NK cells were then treated with inhibitors of significant pathways determined by RNA-seq and analyzed by NKCA, ELISA, and western blot analyses.

RESULTS

Increased peripheral NK cell activated populations were observed in patients treated with metformin. NK cell tumor infiltration was enhanced in patients with HNSCC treated with metformin preoperatively. Metformin increased antitumorigenic cytokines ex vivo, including significant increases in perforin. Metformin increased HNSCC NK cell cytotoxicity and inhibited the CXCL1 pathway while stimulating the STAT1 pathway within HNSCC NK cells. Exogenous CXCL1 prevented metformin-enhanced NK cell-mediated cytotoxicity. Metformin-mediated NK cell cytotoxicity was found to be AMP-activated protein kinase independent, but dependent on both mechanistic target of rapamycin and pSTAT1.

CONCLUSIONS

Our data identifies a new role for metformin-mediated immune antitumorigenic function through NK cell-mediated cytotoxicity and downregulation of CXCL1 in HNSCC. These findings will inform future immunomodulating therapies in HNSCC.

Potentiation of temozolomide activity against glioblastoma cells by aromatase inhibitor letrozole

PURPOSE

The DNA alkylating agent temozolomide (TMZ), is the first-line therapeutic for the treatment of glioblastoma (GBM). However, its use is confounded by the occurrence of drug resistance and debilitating adverse effects. Previously, we observed that letrozole (LTZ), an aromatase inhibitor, has potent activity against GBM in pre-clinical models. Here, we evaluated the effect of LTZ on TMZ activity against patient-derived GBM cells.

METHODS

Employing patient-derived G76 (TMZ-sensitive), BT142 (TMZ-intermediately sensitive) and G43 and G75 (TMZ-resistant) GBM lines we assessed the influence of LTZ and TMZ on cell viability and neurosphere growth. Combination Index (CI) analysis was performed to gain quantitative insights of this interaction. We then assessed DNA damaging effects by conducting flow-cytometric analysis of ˠH2A.X formation and induction of apoptotic signaling pathways (caspase3/7 activity). The effects of adding estradiol on LTZ-induced cytotoxicity and DNA damage were also evaluated.

RESULTS

Co-treatment with LTZ at a non-cytotoxic concentration (40 nM) reduced TMZ IC50 by 8, 37, 240 and 640 folds in G76, BT-142, G43 and G75 cells, respectively. The interaction was deemed to be synergistic based on CI analysis. LTZ co-treatment also significantly increased DNA damaging effects of TMZ. Addition of estradiol abrogated these LTZ effects.

CONCLUSIONS

LTZ increases DNA damage and synergistically enhances TMZ activity in TMZ sensitive and TMZ-resistant GBM lines. These effects are abrogated by the addition of exogenous estradiol underscoring that the observed effects of LTZ may be mediated by estrogen deprivation. Our study provides a strong rationale for investigating the clinical potential of combining LTZ and TMZ for GBM therapy.

Association of Neoadjuvant Pembrolizumab for Oral Cavity Squamous Cell Carcinoma With Adverse Events After Surgery in Treatment-Naive Patients

Importance

Pembrolizumab, a monoclonal antibody targeting programmed cell death 1, is currently approved by the US Food and Drug Administration for recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). The potential neoadjuvant role of programmed cell death 1 inhibitors in primary surgical management of HNSCC and effects on surgical outcomes are poorly understood.

Objective

To evaluate the incidence of postoperative adverse events in treatment-naive patients with advanced oral cavity cancer receiving neoadjuvant pembrolizumab when compared with matched controls, as part of a window-of-opportunity multi-institutional clinical trial assessing neoadjuvant pembrolizumab for locally advanced HNSCC.

Design, Setting, and Participants

This retrospective cohort study at a single tertiary academic institution included treatment-naive patients with local regionally advanced oral cavity squamous cell carcinoma (OCSCC) who were undergoing surgical resection.

Exposures

Patients with local regionally advanced resectable OCSCC who received neoadjuvant pembrolizumab were retrospectively reviewed for postoperative adverse events. Controls were matched by age, race, smoking status, and overall cancer stage based on historical data at the same institution. Matched-cohort analysis was performed using a McNemar test to assess differences between the groups.

Main Outcomes and Measures

Incidence of adverse events following surgical resection of advanced OCSCC within 30 days of surgery and on continued follow-up.

Results

A total of 64 patients (32 as part of the prospective clinical trial and 32 as controls; mean [SD] age, 59.6 [10.3] years; 28 [44%] women) were included in the analysis. Postoperative adverse events in the 32 patients receiving pembrolizumab included lymphedema (n = 20 [63%]), trismus (n = 7 [22%]), return to operating room (n = 7 [22%]), wound infection (n = 7 [22%]), fistula (n = 6 [19%]), wound dehiscence (n = 4 [13%]), flap failure (n = 3 [9%]), and hematoma (n = 2 [6%]). The matched control group demonstrated similar complication rates without considerable differences, except for trismus (n = 16 [50%]), which was greater by a difference of 28.1% (95% CI, 5.6%-50.6%) in the control group.

Conclusions and Relevance

This cohort study examined surgical complications among patients with local regionally advanced OCSCC treated with neoadjuvant pembrolizumab and found that serious adverse events were similar to those in patients who underwent standard-of-care treatment. This suggests that there is no increased perioperative morbidity in the use of preoperative treatment with immunotherapy. Further prospective studies are needed to validate these findings for oral cavity cancer and other subsites of the head and neck.

P11.03.B BXQ-350: Modulating ceramide and Sphingosine-1-Phosphate for anti-tumor activity and potential mitigation of chemotherapy induced peripheral neuropathy

Background

Sphingolipids are a class of bioactive signaling molecules implicated in multiple cellular processes and molecular pathways. Many publications have indicated that among these sphingolipids, sphingosine-1-phosphate (S1P) is a key sphingolipid that promotes cancer cell survival and proliferation, activates multiple oncogenic pathways, and stimulates immuno-suppressor cell populations promoting a pro-tumoral microenvironment. Many of these publications have also implicated S1P with chemotherapy induced peripheral neuropathy, a debilitating and serious side effect that may impact therapeutic treatments and patient’s quality of life.

Material and Methods

BXQ-350 is a nanovesicle of Saposin C, an allosteric activator of sphingolipid metabolism, that has broad anticancer activity, potentially in part by lowering systemic S1P levels. BXQ-350 was investigated in a Phase 1 dose-escalation safety study in an all-comer cancer patients with advanced solid malignancies, including CNS tumors (NCT02859857) to determine its safety profile and its potential clinical activity as a single agent in cancer patients. Samples were collected to determine pharmacokinetics and explore potential biomarkers.

Results

11 patients (~15% of evaluable patients) with advanced disease had a clinical benefit and amongst these, 8 patients (~11% of evaluable patients) had PFS> 6 months with 2 patients still on study five years after enrollment. Analysis of patient’s samples revealed that BXQ-350 decreases systemic S1P levels in the majority of the patients experiencing a clinical benefit. In addition, several patients with established CIPN spontaneously reported improvements of their symptoms shortly after BXQ-350 administration. Analysis of these patients’ samples also revealed that S1P systemic levels had decreased, as well as pro-inflammatory cytokines associated with CIPN.

Conclusion

While these results are exploratory and preliminary in nature, they suggest that BXQ-350’s mechanism of action may represent a novel anti-cancer approach that may also mitigate CIPN.

Phase II Trial of Adjuvant Nivolumab Following Salvage Resection in Patients with Recurrent Squamous Cell Carcinoma of the Head and Neck

PURPOSE

Locoregional relapse in patients with head and neck squamous cell carcinoma (HNSCC) is common, approaching 50% for some subsites despite multimodality therapy. Salvage surgery is the standard of care, but able to achieve durable control in only a minority of patients. While adjuvant radiotherapy or chemo-radiotherapy is offered to select patients, this approach can be prohibitively toxic. Given the activity and tolerability of programmed death-1 inhibitors in metastatic HNSCC, we investigated the safety and efficacy of adjuvant nivolumab after salvage surgical resection.

PATIENTS AND METHODS

This was an open-label, multi-institutional phase II clinical trial (NCT03355560). Patients with recurrent, resectable HNSCC were enrolled within 6 weeks of salvage surgery. Six 28-day cycles of adjuvant nivolumab were planned. The primary endpoint was 2-year disease-free survival (DFS) more than 58%, based on an institutional historical control group of 71 patients with recurrent HNSCC who underwent salvage surgery.

RESULTS

Between February 2018 and February 2020, 39 patients were enrolled. At a median follow-up of 22.1 months, 2-year DFS was 71.4% [95% confidence interval (CI), 57.8-88.1] and the 2-year overall survival (OS) was 73% (95% CI, 58-91.8). Three of 39 (8%) patients experienced grade 3 treatment-related adverse events and 3 of 39 (8%) discontinued treatment due to side effects. Ten of 39 had locoregional recurrence, while 2 of 10 also had synchronous metastatic disease. There was no difference in DFS between PD ligand-1 (PD-L1)-positive and PD-L1-negative patients. There was a nonsignificant trend toward improved DFS in patients with high tumor mutational burden (P = 0.083).

CONCLUSIONS

Adjuvant nivolumab after salvage surgery in locally recurrent HNSCC is well tolerated and showed improved DFS compared with historical controls.

Current Therapy for Metastatic Head and Neck Cancer: Evidence, Opportunities, and Challenges

Management of metastatic head and neck squamous cell carcinoma is evolving as new systemic therapies have led to improvements in survival, and as advances in locoregional therapy and the increased numbers of patients with HPV-associated cancers who develop oligometastases raise the possibility of ablation of limited numbers of metastases. We review the data regarding first-line immunotherapy in PD-L1-expressing metastatic head and neck squamous cell carcinoma, the experience with aggressive local management of oligometastases, and promising novel immunotherapies, targeted therapies, and HPV-specific treatments. For patients with metastatic head and neck squamous cell carcinoma that is PD-L1 expressing, first-line systemic therapy is pembrolizumab or pembrolizumab with chemotherapy. Inclusion of chemotherapy is associated with higher objective response proportion in all biomarker subgroups and may have a greater impact on survival in HPV-associated cancers. For patients with oligometastatic disease, particularly when metastases are metachronous, current evidence supporting the role of local ablation is limited to a small number of retrospective studies. Based on retrospective data, patients with a smaller number of metastases, lung metastases, and/or virally associated head and neck squamous cell carcinoma are most likely to benefit from an aggressive ablative approach. Additionally, we review emerging evidence for targeted therapy in metastatic head and neck squamous cell carcinoma, including with agents that inhibit mutant HRAS or NOTCH1, or overexpressed EGFR. Studies of antiangiogenic agents in combination with immune checkpoint blockade, and combination immunotherapy, are also under study.

Phase II Clinical Trial of Neoadjuvant and Adjuvant Pembrolizumab in Resectable Local-Regionally Advanced Head and Neck Squamous Cell Carcinoma

PURPOSE

Patients with resected, local-regionally advanced, head and neck squamous cell carcinoma (HNSCC) have a one-year disease-free survival (DFS) rate of 65%-69% despite adjuvant (chemo)radiotherapy. Neoadjuvant PD-1 immune-checkpoint blockade (ICB) has demonstrated clinical activity, but biomarkers of response and effect on survival remain unclear.

PATIENTS AND METHODS

Eligible patients had resectable squamous cell carcinoma of the oral cavity, larynx, hypopharynx, or oropharynx (p16-negative) and clinical stage T3-T4 and/or two or more nodal metastases or clinical extracapsular nodal extension (ENE). Patients received neoadjuvant pembrolizumab 200 mg 1-3 weeks prior to surgery, were stratified by absence (intermediate-risk) or presence (high-risk) of positive margins and/or ENE, and received adjuvant radiotherapy (60-66 Gy) and concurrent pembrolizumab (every 3 weeks × 6 doses). Patients with high-risk HNSCC also received weekly, concurrent cisplatin (40 mg/m2). Primary outcome was one-year DFS. Secondary endpoints were one-year overall survival (OS) and pathologic response (PR). Safety was evaluated with CTCAE v5.0.

RESULTS

From February 2016 to October 2020, 92 patients enrolled. The median age was 59 years (range, 27-80), 30% were female, 86% had stage T3-T4, and 69% had ≥N2. At a median follow-up of 28 months, one-year DFS was 97% (95% CI, 71%-90%) in the intermediate-risk group and 66% (95% CI, 55%-84%) in the high-risk group. Patients with a PR had significantly improved one-year DFS relative to patients without response (93% vs. 72%, hazard ratio 0.29; 95% CI, 11%-77%). No new safety signals were identified.

CONCLUSIONS

Neoadjuvant and adjuvant pembrolizumab increased one-year DFS rate in intermediate-risk, but not high-risk, HNSCC relative to historical control. PR to neoadjuvant ICB is a promising surrogate for DFS.

Patients recently treated for B-lymphoid malignancies show increased risk of severe COVID-19: a CCC19 registry analysis

Patients with B-lymphoid malignancies have been consistently identified as a population at high risk of severe COVID-19. Whether this is exclusively due to cancer-related deficits in humoral and cellular immunity, or whether risk of severe COVID-19 is increased by anti-cancer therapy, is uncertain. Using data derived from the COVID-19 and Cancer Consortium (CCC19), we show that patients treated for B-lymphoid malignancies have an increased risk of severe COVID-19 compared to control populations of patients with non-B-lymphoid hematologic malignancies. Among patients with B-lymphoid malignancies, those who received anti-cancer therapy within 12 months of COVID-19 diagnosis experienced increased COVID-19 severity compared to patients with B-lymphoid malignancies off therapy, after adjustment for cancer status and several other prognostic factors. Our findings suggest that patients recently treated for a B-lymphoid malignancy are at uniquely high risk for severe COVID-19.

Geriatric risk factors for serious COVID-19 outcomes among older adults with cancer: a cohort study from the COVID-19 and Cancer Consortium

BACKGROUND

Older age is associated with poorer outcomes of SARS-CoV-2 infection, although the heterogeneity of ageing results in some older adults being at greater risk than others. The objective of this study was to quantify the association of a novel geriatric risk index, comprising age, modified Charlson comorbidity index, and Eastern Cooperative Oncology Group performance status, with COVID-19 severity and 30-day mortality among older adults with cancer.

METHODS

In this cohort study, we enrolled patients aged 60 years and older with a current or previous cancer diagnosis (excluding those with non-invasive cancers and premalignant or non-malignant conditions) and a current or previous laboratory-confirmed COVID-19 diagnosis who reported to the COVID-19 and Cancer Consortium (CCC19) multinational, multicentre, registry between March 17, 2020, and June 6, 2021. Patients were also excluded for unknown age, missing data resulting in unknown geriatric risk measure, inadequate data quality, or incomplete follow-up resulting in unknown COVID-19 severity. The exposure of interest was the CCC19 geriatric risk index. The primary outcome was COVID-19 severity and the secondary outcome was 30-day all-cause mortality; both were assessed in the full dataset. Adjusted odds ratios (ORs) and 95% CIs were estimated from ordinal and binary logistic regression models.

FINDINGS

5671 patients with cancer and COVID-19 were included in the analysis. Median follow-up time was 56 days (IQR 22-120), and median age was 72 years (IQR 66-79). The CCC19 geriatric risk index identified 2365 (41·7%) patients as standard risk, 2217 (39·1%) patients as intermediate risk, and 1089 (19·2%) as high risk. 36 (0·6%) patients were excluded due to non-calculable geriatric risk index. Compared with standard-risk patients, high-risk patients had significantly higher COVID-19 severity (adjusted OR 7·24; 95% CI 6·20-8·45). 920 (16·2%) of 5671 patients died within 30 days of a COVID-19 diagnosis, including 161 (6·8%) of 2365 standard-risk patients, 409 (18·5%) of 2217 intermediate-risk patients, and 350 (32·1%) of 1089 high-risk patients. High-risk patients had higher adjusted odds of 30-day mortality (adjusted OR 10·7; 95% CI 8·54-13·5) than standard-risk patients.

INTERPRETATION

The CCC19 geriatric risk index was strongly associated with COVID-19 severity and 30-day mortality. Our CCC19 geriatric risk index, based on readily available clinical factors, might provide clinicians with an easy-to-use risk stratification method to identify older adults most at risk for severe COVID-19 as well as mortality.

FUNDING

US National Institutes of Health National Cancer Institute Cancer Center.

Racial Disparities in COVID-19 Outcomes Among Black and White Patients With Cancer

IMPORTANCE

Non-Hispanic Black individuals experience a higher burden of COVID-19 than the general population; hence, there is an urgent need to characterize the unique clinical course and outcomes of COVID-19 in Black patients with cancer.

OBJECTIVE

To investigate racial disparities in severity of COVID-19 presentation, clinical complications, and outcomes between Black patients and non-Hispanic White patients with cancer and COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from the COVID-19 and Cancer Consortium registry from March 17, 2020, to November 18, 2020, to examine the clinical characteristics and outcomes of COVID-19 in Black patients with cancer. Data analysis was performed from December 2020 to February 2021.

EXPOSURES

Black and White race recorded in patient's electronic health record.

MAIN OUTCOMES AND MEASURES

An a priori 5-level ordinal scale including hospitalization intensive care unit admission, mechanical ventilation, and all-cause death.

RESULTS

Among 3506 included patients (1768 women [50%]; median [IQR] age, 67 [58-77] years), 1068 (30%) were Black and 2438 (70%) were White. Black patients had higher rates of preexisting comorbidities compared with White patients, including obesity (480 Black patients [45%] vs 925 White patients [38%]), diabetes (411 Black patients [38%] vs 574 White patients [24%]), and kidney disease (248 Black patients [23%] vs 392 White patients [16%]). Despite the similar distribution of cancer type, cancer status, and anticancer therapy at the time of COVID-19 diagnosis, Black patients presented with worse illness and had significantly worse COVID-19 severity (unweighted odds ratio, 1.34 [95% CI, 1.15-1.58]; weighted odds ratio, 1.21 [95% CI, 1.11-1.33]).

CONCLUSIONS AND RELEVANCE

These findings suggest that Black patients with cancer experience worse COVID-19 outcomes compared with White patients. Understanding and addressing racial inequities within the causal framework of structural racism is essential to reduce the disproportionate burden of diseases, such as COVID-19 and cancer, in Black patients.

Coinfections in Patients with Cancer and COVID-19: A COVID-19 and Cancer Consortium (CCC19) Study

Background

The frequency of coinfections and their association with outcomes have not been adequately studied among patients with cancer and coronavirus disease 2019 (COVID-19), a high-risk group for coinfection.

Methods

We included adult (≥18 years) patients with active or prior hematologic or invasive solid malignancies and laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection, using data from the COVID-19 and Cancer Consortium (CCC19, NCT04354701). We captured coinfections within ±2 weeks from diagnosis of COVID-19, identified factors cross-sectionally associated with risk of coinfection, and quantified the association of coinfections with 30-day mortality.

Results

Among 8765 patients (hospitalized or not; median age, 65 years; 47.4% male), 16.6% developed coinfections: 12.1% bacterial, 2.1% viral, 0.9% fungal. An additional 6.4% only had clinical diagnosis of a coinfection. The adjusted risk of any coinfection was positively associated with age >50 years, male sex, cardiovascular, pulmonary, and renal comorbidities, diabetes, hematologic malignancy, multiple malignancies, Eastern Cooperative Oncology Group Performance Status, progressing cancer, recent cytotoxic chemotherapy, and baseline corticosteroids; the adjusted risk of superinfection was positively associated with tocilizumab administration. Among hospitalized patients, high neutrophil count and C-reactive protein were positively associated with bacterial coinfection risk, and high or low neutrophil count with fungal coinfection risk. Adjusted mortality rates were significantly higher among patients with bacterial (odds ratio [OR], 1.61; 95% CI, 1.33–1.95) and fungal (OR, 2.20; 95% CI, 1.28–3.76) coinfections.

Conclusions

Viral and fungal coinfections are infrequent among patients with cancer and COVID-19, with the latter associated with very high mortality rates. Clinical and laboratory parameters can be used to guide early empiric antimicrobial therapy, which may improve clinical outcomes.

Impact of p16 Status and Anatomical Site in Anti-PD-1 Immunotherapy-Treated Recurrent/Metastatic Head and Neck Squamous Cell Carcinoma Patients

In head and neck squamous cell carcinoma (HNSCC), anti-PD-1 inhibitors are approved for recurrent/metastatic (R/M) disease and anticipated to expand to other indications. The impact of p16 status and anatomical site on overall survival (OS) in immunotherapy-treated HNSCC patients remains unresolved. We performed a retrospective analysis of R/M HNSCC patients receiving anti-PD-1 immunotherapy at our academic medical center with an extensive community satellite network. Fifty-three R/M HNSCC patients were treated with anti-PD-1 immunotherapy and had a median OS of 6 months. Anatomical site was associated with distinct OS; oropharynx and larynx patients have superior OS compared to oral cavity patients. Analysis of the OPSCC subset showed p16+ status as a favorable, independent prognostic biomarker (HR 7.67 (1.23-47.8); p = 0.029). Further studies to assess the link between anatomical site, p16 status, and anti-PD-1 treatment outcomes in large cohorts of R/M HNSCC patients managed in real-world clinical practices and clinical trials should be prioritized.

Immune Checkpoint Inhibitors Regulate K+ Channel Activity in Cytotoxic T Lymphocytes of Head and Neck Cancer Patients

Programmed death receptor-1 (PD-1) and its ligand (PD-L1) interaction negatively regulates T cell function in head and neck squamous cell carcinoma (HNSCC). Overexpression of PD-1 reduces intracellular Ca²⁺ fluxes, and thereby T cell effector functions. In HNSCC patients, PD-1 blockade increases KCa3.1 and Kv1.3 activity along with Ca²⁺ signaling and mobility in CD8⁺ peripheral blood T cells (PBTs). The mechanism by which PD-L1/PD-1 interaction regulates ion channel function is not known. We investigated the effects of blocking PD-1 and PD-L1 on ion channel functions and intracellular Ca²⁺ signaling in CD8⁺ PBTs of HNSCC patients and healthy donors (HDs) using single-cell electrophysiology and live microscopy. Anti-PD-1 and anti-PD-L1 antibodies increase KCa3.1 and Kv1.3 function in CD8⁺ PBTs of HNSCC patients. Anti-PD-1 treatment increases Ca²⁺ fluxes in a subset of HSNCC patients. In CD8⁺ PBTs of HDs, exposure to PD-L1 reduces KCa3.1 activity and Ca²⁺ signaling, which were restored by anti-PD-1 treatment. The PD-L1-induced inhibition of KCa3.1 channels was rescued by the intracellular application of the PI3 kinase modulator phosphatidylinositol 3-phosphate (PI3P) in patch-clamp experiments. In HNSCC CD8⁺ PBTs, anti-PD-1 treatment did not affect the expression of KCa3.1, Kv1.3, Ca²⁺ release activated Ca²⁺ (CRAC) channels, and markers of cell activation (CD69) and exhaustion (LAG-3 and TIM-3). Our data show that immune checkpoint blockade improves T cell function by increasing KCa3.1 and Kv1.3 channel activity in HNSCC patients.

Adjuvant radiation and cetuximab improves local control in head and neck cutaneous squamous cell carcinoma: A phase II study

BACKGROUND

Cutaneous squamous cell carcinoma of the head/neck (CSCCHN) is common due to chronic sun exposure. As CSCCHN highly expresses EGFR, we prospectively studied postoperative concurrent cetuximab with radiotherapy for locally advanced CSCCHN (LA-CSCCHN).

MATERIALS AND METHODS

Single-institutional phase II trial of LA-CSCCHN (NCT XXXX). Adjuvant radiation was given with concurrent cetuximab. Primary endpoint of 2-year LRC and secondary objectives of 2-year disease-free survival (DFS) and 2-year OS were assessed by Kaplan-Meier analysis.

RESULTS

Twenty-four patients ages 47-88 (median 71 years) were treated from 2014 to 2017. Fourteen patients had T3/4 disease, 5 had N1 disease, and 7 were N2/3. At median follow-up of 42 months, median OS and DFS was not reached and 64 months. Two-year OS was 75%, 2-year DFS was 70.8%. LRC was 91.1% at 2 years. All grade 3 adverse events were related to skin toxicity (12.5% radiation-related dermatitis, 16.7% cetuximab-related rash).

CONCLUSIONS

LRC compares favorably to historical data examining postoperative radiation alone but requires further investigation.

Human Papillomavirus and Survival of Sinonasal Squamous Cell Carcinoma Patients: A Systematic Review and Meta-Analysis

Simple Summary

Human papillomavirus (HPV) has been associated with multiple cancers in the anogenital and upper aerodigestive tracts. In the head and neck region, HPV-positive cancers are common in oropharynx, with rising incidence and a well-established association with more favorable patient outcomes. However, the relationship with prognosis of sinonasal squamous cell carcinoma (SNSCC) has been much less often studied and is presently unclear. To better elucidate this relationship, we performed a systematic review and meta-analysis of the biomedical literature to determine the aggregate effect across studies. In doing so, we observed significantly better overall survival associated with HPV-positive SNSCC. Therefore, we conclude that HPV testing may be useful for determining patient prognosis and potentially guiding treatment decisions.

Abstract

Human papillomavirus (HPV) is detectable in a subset of sinonasal squamous cell carcinoma (SNSCC), but the impact on patient outcomes is presently unclear due to a modest number of studies with limited statistical power. Therefore, we conducted a systematic review and meta-analysis to better clarify this relationship. A PubMed search was conducted to identify all studies reporting on overall (OS) or disease-free survival (DFS) for SNSCC by HPV status. Hazard ratios (HR) and corresponding 95% confidence intervals (CI) were extracted or, when not provided, indirectly estimated from each manuscript. Summary survival curves for 5-year OS and estimating survival probability by HPV status at pre-specified time intervals from study-specific Kaplan-Meier curves generated 2-year DFS. Log HRs and log CIs were combined across studies to generate summary estimates and a corresponding 95% CIs for OS and DFS. We identified ten unique studies reporting on OS and four for DFS. We observed a significant association between HPV and OS (summary HR = 0.51, 95% CI: 0.38–0.70) with relatively low heterogeneity between studies. These results indicate that HPV is a significant predictor of more favorable survival for SNSCC, and thus may be a useful biomarker for prognostication and, potentially, treatment modulation.

Managing Recurrent Metastatic Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) treatment is often associated with high morbidity especially in the recurrent and/or metastatic (R/M) setting, limiting effective treatment options. Local disease control is important. Therefore, local therapies including reirradiation and salvage surgery, either alone or in combination with systemic treatment, may be used for selected patients with R/M HNSCC. Although chemotherapy and targeted agents have modest efficacy in HNSCC, the advent of immunotherapy has revolutionized the treatment paradigm of R/M HNSCC. Multiple trials have resulted in the past 5 years advocating for its use alone or in combination with chemotherapy.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium

BACKGROUND

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies.

PATIENTS AND METHODS

Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients).

RESULTS

A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality.

CONCLUSIONS

Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies.

CLINICAL TRIAL IDENTIFIER

NCT04354701.

Pre-treatment absolute lymphocyte count predicts for improved survival in human papillomavirus (HPV)-driven oropharyngeal squamous cell carcinoma

BACKGROUND

The prognostic value of pretreatment complete blood count (CBC) data, including absolute lymphocyte count (ALC) and the neutrophil-to-lymphocyte ratio (NLR), has been reported for many diseases with decreased ALC and increased absolute neutrophil count (ANC) and NLR values correlating with worse outcomes. There is minimal data relating these hematologic parameters to oropharyngeal squamous cell carcinoma (OPSCC) prognosis. This study evaluates the prognostic value of pretreatment CBC data in OPSCC on overall survival (OS) and progression-free survival (PFS) in relation to HPV status.

METHODS

A single-institutional retrospective review of patients with pretreatment hematologic data who received radiation for OPSCC was performed. Univariate and multivariate (UVA/MVA) Cox proportional hazard regression analyses were performed to identify prognostic variables. Translational studies related outcomes to the degree of tumor-infiltrating lymphocytes (TILs) in histologic specimens.

RESULTS

From 2007 to 2018, 201 patients were treated for OPSCC. Median follow-up was 40 months. 3-year OS was 86.2% in the HPV-positive cohort, 46.3% for HPV-negative. Median NLR was 3.04. NLR ≥ 3 was associated with worse PFS (HR 1.67, p = 0.044. In the subset of 158 HPV + patients, MVA revealed increasing ALC to be associated with improved OS (HR 0.53; p = 0.040) and PFS (HR = 0.48; p = 0.0075). On UVA, high-TIL infiltration at diagnosis was associated with improved OS.

CONCLUSION

In a cohort of HPV + OPSCC patients, increasing ALC is associated with improved OS and PFS. Our study is the first to identify pre-treatment ALC as an independent prognostic factor in HPV-associated OPSCC.

Targeted knockdown of the adenosine A2A receptor by lipid NPs rescues the chemotaxis of head and neck cancer memory T cells

In solid malignancies, including head and neck squamous cell carcinoma (HNSCC), the immunosuppressive molecule adenosine, which accumulates in the tumor, suppresses cytotoxic CD8⁺ T cell functions including chemotaxis and tumor infiltration. Adenosine functions through binding to the adenosine A_2A receptor (A_2AR) present on T cells. In order to increase T cell migration into the tumor, the negative effect of adenosine must be abrogated. Systemic drug treatments targeting A_2AR are available; however, they could lead to negative toxicities due to the broad expression of this receptor. Herein, we developed a lipid nanoparticle (NP)-based targeted delivery approach to knock down A_2AR in T cells in order to increase their chemotaxis in the presence of adenosine. By using flow cytometry, immunofluorescence, qRT-PCR, and 3D-chemotaxis, we demonstrated that CD45RO-labeled nanoparticles delivering ADORA2A gene-silencing-RNAs decreased ADORA2A mRNA expression and rescued the chemotaxis of HNSCC CD8⁺ memory T cells. Overall, the data indicate that targeting the adenosine signaling pathway with lipid NPs is successful at suppressing the inhibitory effect of adenosine on the chemotaxis of HNSCC memory T cells, which could ultimately help increase T cell infiltration into the tumor.

Hypothyroidism in Head and Neck Squamous Cell Carcinoma Patients Receiving Radiotherapy With or Without Immune Checkpoint Inhibitors

OBJECTIVES/HYPOTHESIS

Hypothyroidism is a relatively common complication of head and neck squamous cell carcinoma (HNSCC) treatment. The objective of this study was to determine whether the addition of programmed death ligand-1 (PD-1) or programmed death ligand-1 (PD-L1) inhibition (anti-PD-1/PD-L1 therapy) to standard treatment increases the risk of hypothyroidism in HNSCC.

STUDY DESIGN

Retrospective Cohort.

METHODS

This is a retrospective, single institutional cohort study. Patients who received radiotherapy (RT) for HNSCC were identified in the electronic medical record. Patient factors collected include age, sex, body mass index (BMI), smoking status, alcohol use, Charlson comorbidity index, and HNSCC treatment records. The rate of hypothyroidism for patients with HNSCC receiving RT (+/- chemotherapy and surgery) (RT group, n = 101) was compared to that of HNSCC patients receiving RT (+/- chemotherapy and surgery) + anti-PD-1/PD-L1 therapy, either concurrently or after RT (RT + anti-PD-1/PD-L1 group, n = 38).

RESULTS

There was no significant difference in the rate of clinical or subclinical hypothyroidism between the two groups. Multinomial logistic regression found no significant difference in hypothyroidism based on age, sex, or BMI.

CONCLUSIONS

The addition of anti-PD-1/PD-L1 therapy to standard HNSCC treatment does not significantly increase the risk of developing hypothyroidism.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:E2413-E2419, 2021.

Glutaminase inhibition with telaglenastat (CB-839) improves treatment response in combination with ionizing radiation in head and neck squamous cell carcinoma models

The efficacy of ionizing radiation (IR) for head and neck cancer squamous cell carcinoma (HNSCC) is limited by poorly understood mechanisms of adaptive radioresistance. Elevated glutaminase gene expression is linked to significantly reduced survival (p < 0.03). The glutaminase inhibitor, telaglenastat (CB-839), has been tested in Phase I/II cancer trials and is well tolerated by patients. This study investigated if telaglenastat enhances the cellular response to IR in HNSCC models. Using three human HNSCC cell lines and two xenograft mouse models, we examined telaglenastat's effects on radiation sensitivity. IR and telaglenastat combinatorial treatment reduced cell survival (p ≤ 0.05), spheroid size (p ≤ 0.0001) and tumor growth in CAL-27 xenograft bearing mice relative to vehicle (p ≤ 0.01), telaglenastat (p ≤ 0.05) or IR (p ≤ 0.01) monotherapy. Telaglenastat significantly reduced the Oxygen Consumption Rate/Extracellular Acidification Rate ratio in CAL-27 and HN5 cells in the presence of glucose and glutamine (p ≤ 0.0001). Telaglenastat increased oxidative stress and DNA damage in irradiated CAL-27 cells. These data suggest that combination treatment with IR and telaglenastat leads to an enhanced anti-tumor response. This pre-clinical data, combined with the established safety of telaglenastat justifies further investigation for the combination in HNSCC patients.

PD1 blockade enhances K+ channel activity, Ca2+ signaling, and migratory ability in cytotoxic T lymphocytes of patients with head and neck cancer

Background

Immunotherapy has emerged as a promising treatment modality for head and neck squamous cell carcinoma (HNSCC). Pembrolizumab, an anti-programmed death 1 antibody, is an immunotherapy agent currently approved for metastatic HNSCC and curative intent clinical trials. Although clinical responses to pembrolizumab are promising, many patients fail to respond. However, it is well known that T cell cytotoxicity and chemotaxis are critically important in the elimination of HNSCC tumors. These functions depend on ion channel activity and downstream Ca²⁺ fluxing abilities, which are defective in patients with HNSCC. The purpose of this study was to elucidate the effects of pembrolizumab on potassium (K⁺) channel (KCa3.1 and Kv1.3) activity, Ca²⁺ fluxes, and chemotaxis in the cytotoxic T cells of patients with HNSCC and to determine their correlation with treatment response.

Methods

Functional studies were conducted in CD8⁺ peripheral blood T cells (PBTs) and tumor infiltrating lymphocytes (TILs) from patients with HNSCC treated with pembrolizumab. Untreated patients with HNSCC were used as controls. The ion channel activity of CD8⁺ T cells was measured by patch-clamp electrophysiology; single-cell Ca²⁺ fluxing abilities were measured by live microscopy. Chemotaxis experiments were conducted in a three-dimensional collagen matrix. Pembrolizumab patients were stratified as responders or non-responders based on pathological response (percent of viable tumor remaining at resection; responders: ≤80% viable tumor; non-responders: >80% viable tumor).

Results

Pembrolizumab increased K⁺ channel activity and Ca²⁺ fluxes in TILs independently of treatment response. However, in PBTs from responder patients there was an increased KCa3.1 activity immediately after pembrolizumab treatment that was accompanied by a characteristic increase in Kv1.3 and Ca²⁺ fluxes as compared with PBTs from non-responder patients. The effects on Kv1.3 and Ca²⁺ were prolonged and persisted after tumor resection. Chemotaxis was also improved in responder patients’ PBTs. Unlike non-responders’ PBTs, pembrolizumab increased their ability to chemotax in a tumor-like, adenosine-rich microenvironment immediately after treatment, and additionally they maintained an efficient chemotaxis after tumor resection.

Conclusions

Pembrolizumab enhanced K⁺ channel activity, Ca²⁺ fluxes and chemotaxis of CD8⁺ T cells in patients with HNSCC, with a unique pattern of response in responder patients that is conducive to the heightened functionality of their cytotoxic T cells.

Determining the molecular landscape and impact on prognosis in HPV-associated head and neck cancer

BACKGROUND

Human papillomavirus (HPV) associated head and neck squamous cell carcinoma (HNSCC) has a better prognosis than HNSCC due to other risk factors. However, there is significant heterogeneity within HPV-associated HNSCC and 25% of these patients still do poorly despite receiving aggressive therapy. We currently have no good molecular tools to differentiate and exclude this "high-risk" sub-population and focus on "low-risk" patients for clinical trials. This has been a potential barrier to identifying successful de-escalation treatment strategies in HPV-associated HNSCC. We conducted an analysis of molecular markers with a well-known role in the pathogenesis of HPV-associated HNSCC and hypothesized that these markers could help independently predict recurrence and prognosis in these patients and therefore help identify at the molecular level "low-risk" patients suitable for de-escalation trials.

METHODS

We analyzed 24 tumor specimens of patients with p16+ HNSCC who underwent definitive resection as primary treatment. Tissue microarray (TMA) was generated from the 24 pathology blocks and immunohistochemistry (IHC) was performed using highly specific antibodies for our chosen biomarkers (PI3K-PTEN, AKT pathway, mTOR, 4EBP1, S6, and pAMPK, ERCC-1). Transcriptome data was also obtained for 7 p16+ HNSCC patients from The Cancer Genome Atlas (TCGA). Data from the TMA and TCGA were analyzed for association of relapse-free survival (RFS) and overall survival (OS) with protein and gene expression of the chosen biomarkers.

RESULTS

Increased pAMPK protein activity by IHC and AMPK gene expression by TCGA gene expression data was correlated with improved RFS with a trend towards statistical significance.

CONCLUSIONS

This data suggests that increased pAMPK activity and expression may portend a better prognosis in HPV-associated HNSCC undergoing primary definitive resection. However, these findings require validation in larger studies.

Abstract LB-140: Phase 1b/2 study of an intratumoral TLR9 agonist spherical nucleic acid (AST-008) and pembrolizumab: Evidence of immune activation

Background: AST-008 is a novel spherical nucleic acid configuration of a toll-like receptor 9 (TLR9) agonist oligonucleotide, designed to trigger anti-tumor immune responses. Here we focus on immune activation upon AST-008 injection in the phase 1b/2 study in patients with advanced solid tumors (NCT03684785). Materials and Methods: AST-008 was injected intratumorally (IT) into one or more tumors QW for 8 doses, then Q3W thereafter, at doses from 2 to 32 mg. Starting at week 3, pembrolizumab was administered per label until toxicity or progression. Peripheral blood immune cell profiling and cytokine/chemokine analyses were performed before and 24 hours after both the first AST-008 dose (week 1) and the first combination dose (week 3). Serial tumor biopsies of lesions were collected from both AST-008-injected lesions and non-injected (“witness”) lesions at baseline, after IT AST-008 monotherapy, and after combination therapy. Results: Seventeen patients have been enrolled in the dose escalation cohort: median age 66 [range: 30-86], 82% male, median ECOG 1 [0-1]. Dose dependent lymphocyte activation was observed after IT AST-008. AST-008 dosing alone (16 mg cohort, n = 3) increased activated fractions of CD4+ (33%) and CD8+ T cells (64%), monocytes (97%) and NK cells (94%), compared to baseline (15%, 22%, 4%, and 37%, respectively). At AST-008 doses of 8 and 16 mg, the cell activation response within a dose level was generally similar in the presence or absence of pembrolizumab. In addition, the cytokines/chemokines IL-12p40, IL-1RA, IP-10, and MCP-1 were induced in a dose-proportional manner after IT AST-008 mono- or combination therapy. IT AST-008 resulted in average fold increase of 5, 12, and 16 for doses of 2, 4, and 8 mg dose cohorts, respectively, in IP-10 concentration from baseline (n = 11). Generally, combination therapy with pembrolizumab and AST-008 at doses of 2 and 4 mg produced a cytokine/chemokine response that was smaller than AST-008 alone (n = 5), but 8 mg dose responses were similar after monotherapy or combination therapy (n = 3). Preliminary analysis of serial biopsies by Nanostring revealed increased T cells and cytotoxic cells in the injected lesion after AST-008 dosing (n = 4) and in the non-injected witness lesion after combination therapy (n = 6). Combination therapy produced increases in B cells, T cells, cytotoxic cells and macrophages the AST-008 injected lesions (n = 6). Further PD data are being collected. The emerging safety profile consists mostly of grade (G) 1 and 2 injection site reactions and flu-like symptoms, reflecting local and systemic immune activation. One G3 lymphocytopenia has been observed, with no clinical consequences. No AST-008-related serious AEs or DLTs have been reported. Conclusions: IT AST-008 is well tolerated at the doses administered and is associated with dose-proportional systemic immune activation. Gene expression analysis suggests increased lymphocytes in the injected tumor after IT AST-008 and in both injected and witness tumors after combination therapy.

Citation Format: Mohammed M. Milhem, Cesar A. Perez, Glenn J. Hanna, Trisha M. Wise-Draper, Shailender Bhatia, Alice S. Bexon, Weston L. Daniel, Steven J. O'Day. Phase 1b/2 study of an intratumoral TLR9 agonist spherical nucleic acid (AST-008) and pembrolizumab: Evidence of immune activation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-140.

Successful use of a therapeutic trial of graduated volume and dose escalation for postoperative head and neck radiotherapy in a Fanconi anemia patient

BACKGROUND

Patients with the heritable disease, Fanconi anemia (FA), have a 500-fold risk of developing head and neck squamous cell carcinomas (HNSCC). However, the use of conventional cytotoxic agents including radiation therapy and cisplatin-based chemotherapy is contraindicated in patients with FA due to underlying DNA repair defects.

METHODS/RESULTS

We present a young FA patient with recurrent HNSCC and high-risk pathologic features treated with a therapeutic trial of chemoradiation. This novel strategy employs a gentle radiation dose and volume escalation with concurrent pembrolizumab. The patient completed the entire course of therapy with no treatment delays or interruptions.

CONCLUSIONS

The FA patient population has a clear need for adjuvant treatment regimens given their predilection for HNSCC. A therapeutic trial may allow FA and other radiosensitive patients to trial radiation with the option to terminate treatment before any severe side effects occur and for some to complete a full course of treatment.

COVID-19 pandemic and impact on cancer clinical trials: An academic medical center perspective

The COVID-19 pandemic changed health-care operations around the world and has interrupted standard clinical practices as well as created clinical research challenges for cancer patients. Cancer patients are uniquely susceptible to COVID-19 infection and have some of the worst outcomes. Importantly, cancer therapeutics could potentially render cancer patients more susceptible to demise from COVID-19 yet the poor survival outcome of many cancer diagnoses outweighs this risk. In addition, the pandemic has resulted in risks to health-care workers and research staff driving important change in clinical research operations and procedures. Remote telephone and video visits, remote monitoring, electronic capture of signatures and data, and limiting sample collections have allowed the leadership in our institution to ensure the safety of our staff and patients while continuing critical clinical research operations. Here we discuss some of these unique challenges and our response to change that was necessary to continue cancer clinical research; and, the impacts the pandemic has caused including increases in efficiency for our cancer research office.

Targeting HER2 with Trastuzumab Deruxtecan: A Dose-Expansion, Phase I Study in Multiple Advanced Solid Tumors

HER2-targeted therapies are approved only for HER2-positive breast and gastric cancers. We assessed the safety/tolerability and activity of the novel HER2-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd) in 60 patients with pretreated, HER2-expressing (IHC ≥ 1+), non-breast/non-gastric or HER2-mutant solid tumors from a phase I trial (NCT02564900). Most common (>50%) treatment-emergent adverse events (TEAE) were nausea, decreased appetite, and vomiting. Two drug-related TEAEs were associated with fatal outcomes. The confirmed objective response rate (ORR) was 28.3% (17/60). Median progression-free survival (PFS) was 7.2 [95% confidence interval (CI), 4.8-11.1] months. In HER2-mutant non-small cell lung cancer (NSCLC), ORR was 72.7% (8/11), and median PFS was 11.3 (95% CI, 8.1-14.3) months. Confirmed responses were observed in six tumor types, including HER2-expressing NSCLC, colorectal cancer, salivary gland cancer, biliary tract cancer, endometrial cancer, and HER2-mutant NSCLC and breast cancer. Results suggest T-DXd holds promise for HER2-expressing/mutant solid tumors. SIGNIFICANCE: T-DXd demonstrated promising activity in a heterogeneous patient population with heavily pretreated HER2-expressing or HER2-mutant solid tumors, especially HER2-mutant NSCLC. The safety profile was generally acceptable. Interstitial lung disease can be severe and requires prompt monitoring and intervention. Further research of T-DXd is warranted to address these unmet medical needs.See related commentary by Rolfo and Russo, p. 643.This article is highlighted in the In This Issue feature, p. 627.

A Compartmentalized Reduction in Membrane-Proximal Calmodulin Reduces the Immune Surveillance Capabilities of CD8+ T Cells in Head and Neck Cancer

The limited ability of cytotoxic CD8⁺ T cells to infiltrate solid tumors and function within the tumor microenvironment presents a major roadblock to effective immunotherapy. Ion channels and Ca²⁺-dependent signaling events control the activity of T cells and are implicated in the failure of immune surveillance in cancer. Reduced KCa3.1 channel activity mediates the heightened inhibitory effect of adenosine on the chemotaxis of circulating T cells from head and neck squamous cell carcinoma (HNSCC) patients. Herein, we conducted experiments that elucidate the mechanisms of KCa3.1 dysfunction and impaired chemotaxis in HNSCC CD8⁺ T cells. The Ca²⁺ sensor calmodulin (CaM) controls multiple cellular functions including KCa3.1 activation. Our data showed that CaM expression is lower in HNSCC than healthy donor (HD) T cells. This reduction was due to an intrinsic decrease in the genes encoding CaM combined to the failure of HNSCC T cells to upregulate CaM upon activation. Furthermore, the reduction in CaM was confined to the plasma membrane and resulted in decreased CaM-KCa3.1 association and KCa3.1 activity (which was rescued by the delivery of CaM). IFNγ production, also Ca²⁺- and CaM-dependent, was instead not reduced in HNSCC T cells, which maintained intact cytoplasmic CaM and Ca²⁺ fluxing ability. Knockdown of CaM in HD T cells decreased KCa3.1 activity, but not IFNγ production, and reduced their chemotaxis in the presence of adenosine, thus recapitulating HNSCC T cell dysfunction. Activation of KCa3.1 with 1-EBIO restored the ability of CaM knockdown HD T cells to chemotax in the presence of adenosine. Additionally, 1-EBIO enhanced INFγ production. Our data showed a localized downregulation of membrane-proximal CaM that suppressed KCa3.1 activity in HNSCC circulating T cells and limited their ability to infiltrate adenosine-rich tumor-like microenvironments. Furthermore, they indicate that KCa3.1 activators could be used as positive CD8⁺ T cell modulators in cancers.

Phase 1 dose-finding study of metformin in combination with concurrent cisplatin and radiotherapy in patients with locally advanced head and neck squamous cell cancer

BACKGROUND

The 5-year overall survival (OS) rate remains at 50% for patients with locally advanced head and neck squamous cell carcinoma (LAHNSCC), thereby underscoring the need for improved treatments. An antidiabetic agent, metformin, was found in retrospective studies to improve survival in patients with HNSCC. Therefore, the authors conducted a phase 1 dose escalation study combining metformin with chemoradiotherapy in patients with LAHNSCC.

METHODS

Nondiabetic patients with LAHNSCC were enrolled in the current study to receive escalating doses of metformin and CRT based on the modified toxicity probability interval design. Metformin cohort doses included 2000 mg, 2550 mg, and 3000 mg daily in divided doses in addition to cisplatin (at a dose of 100 mg/m² on days 1, 22, and 43) and standard radiotherapy (70 grays). Adverse events were categorized as per the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03).

RESULTS

Twenty patients were enrolled, 2 of whom withdrew consent. The median age of the patients was 56 years and the majority were male (83%), were white (88%), had p16-positive disease (72%), and were tobacco users (61%). The median length of metformin exposure was 28.5 days. The most common grade ≥3 toxicities were nausea (11%), vomiting (11%), mucositis (6%), acute kidney injury (17%), anemia (6%), and leukopenia (11%). Dose-limiting toxicities included diarrhea and acute kidney injury. After a median follow-up of 19 months, the 2-year overall survival and progression-free survival rates were 90% and 84%, respectively. No hypoglycemia events or lactic acidosis were observed. Cisplatin administration did not appear to affect metformin pharmacokinetics. The maximum tolerated dose for metformin could not be determined given the limited number of patients who tolerated metformin during chemoradiotherapy.

CONCLUSIONS

To the authors' knowledge, the current study is the first phase 1 trial combining metformin with chemoradiotherapy. Rates of overall survival and progression-free survival were encouraging in this limited patient population, and warrant further investigation in a phase 2 trial.

Differential expression and prognostic value of long non-coding RNA in HPV-negative head and neck squamous cell carcinoma

BACKGROUND

Long non-coding RNA (lncRNA) has emerged as a new avenue of interest due to its various biological functions in cancer. Abnormal expression of lncRNA has been reported in other malignancies but has been understudied in head and neck squamous cell carcinoma (HNSCC).

METHODS

The lncRNA expression was interrogated via quantitative real-time polymerase chain reaction (qRT-PCR) array for 19 human papillomavirus (HPV)-negative HNSCC tumor-normal pairs. The Cancer Genome Atlas (TCGA) was used to validate these results. The association between differentially expressed lncRNA and survival outcomes was analyzed.

RESULTS

Differential expression was validated for 5 lncRNA (SPRY4-IT1, HEIH, LUCAT1, LINC00152, and HAND2-AS1). There was also an inverse association between MEG3 expression (not significantly differentially expressed in TCGA tumors but highly variable expression) and 3-year recurrence-free survival (RFS).

CONCLUSION

We identified and validated differential expression of 5 lncRNA in HPV-negative HNSCC. Low MEG3 expression was associated with favorable 3-year RFS, although the significance of this finding remains unclear.

Abstract 26: Exosomal microRNA as salivary biomarkers of head and neck squamous cell carcinoma

Head and neck cancer is the 10th most common cancer overall and 5th most common among men in the United States, the vast majority of which are squamous cell carcinoma (HNSCC). Despite approximately two-thirds of cases being diagnosed at an advanced stage, the only routine screening approach currently in widespread use is visual inspection and palpation, which is provided by dentists and clinicians on an opportunistic basis, lacks sensitivity, and varies according to the skill of the clinician. This underscores the urgent and compelling need for establishment of novel and effective biomarkers to facilitate early detection. Exosomes may offer a new avenue for discovery and development of novel biomarkers of HNSCC. These nanosized (40-150 nm), membrane-encapsulated vesicles are released by both normal and malignant cells into the extracellular space and function as intercellular signaling vectors through the horizontal transfer of biologic molecules, including microRNA (miRNA), which can affect the phenotype of recipient cells. Importantly, exosomes are present in essentially all extracellular biofluids, including saliva, and thus can readily be collected by noninvasive means. Through previous cell culture work, we observed striking differences in exosomal miRNA secreted by HNSCC cells relative to healthy oral epithelial cells, with a high degree of overlap in exosomal miRNA profiles across HNSCC cell lines. Although salivary exosomes have been theorized to be a potentially powerful biomarker source for HNSCC, there has been an extreme paucity of work conducted in this arena. To begin to address this question, we conducted a small pilot study in which we collected 2-mL whole-saliva samples from 5 HNSCC cases (collected prior to initiation of treatment) and 5 cancer-free controls. Exosomes were isolated from each saliva sample via differential ultracentrifugation, and total RNA was extracted for miRNA-sequencing (miRNA-seq), which was performed by the University of Cincinnati Genomics, Epigenomics & Sequencing Core (GESC). The number of reads for each sample during miRNA-seq ranged from 1.6 million to 27.4 million reads (median = 12.4 million). After aligning the reads to all human miRNA sequences catalogued in miRBase, there were a total of 1,334 mature miRNA transcripts detected across samples, with 307 transcripts (12%) detected solely in salivary exosomes from cases. Moreover, despite the small sample size of the pilot study, we observed significant differential exosomal secretion of miR-10b-5p (p = 0.006), with transcripts present at relatively high levels in salivary exosomes from 3 of the 5 cases but none detected in those from the 5 controls. We also preliminarily assessed the translational potential of 8 miRNA transcripts that were solely and universally expressed by our HNSCC cell lines (i.e. not secreted by healthy oral epithelial cells) in our previous cell culture work using the salivary exosome miRNA-seq data for the 5 cases and 5 controls. All 8 transcripts were detected in salivary exosomes obtained from the 5 HNSCC cases. In particular, miR-486-5p and miR-486-3p showed considerable promise, with 40% of cases expressing drastically higher levels of these transcripts relative to controls. When either miR-486-5p or miR-486-3p was combined with miR-10b-5p, the substantial separation of these markers could clearly distinguish 80% (4/5) of the HNSCC cases from controls. These findings demonstrate the potential of salivary miRNA as biomarkers of HNSCC and highlight the necessity of further workup and validation in full-scale studies involving human saliva.

Citation Format: Scott M. Langevin, Damaris Kuhnell, Xiang Zhang, Trisha M. Wise-Draper, Keith A. Casper. Exosomal microRNA as salivary biomarkers of head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 26.

Abstract A51: Investigation of the DEK oncogene as a blood biomarker for breast cancer

Breast cancer (BC) is one of the leading causes of death for women in the United States. This is due, in part, because women wait too long to get a diagnosis or the disease returns, sometimes years later, due to ineffective treatment. Therefore, it is critically important to identify biomarkers that can better inform clinicians while providing a screening test more amenable to patients than mammograms. We are investigating the feasibility of using DEK protein levels in patient plasma as a biomarker for disease stage and prognosis. DEK is a chromatin-organizing protein that functions in DNA replication and repair, transcription, and mRNA splicing. The DEK oncoprotein is highly upregulated in many types of cancer including breast, head and neck, and melanoma. Using human cell culture and murine models, our previous studies have shown that DEK is functionally important for the promotion of cellular growth, invasion/metastasis, drug resistance, and breast cancer stem cell maintenance. Work by the Markovitz laboratory indicated that DEK is secreted by macrophages as a pro-inflammatory signaling molecule and can be internalized by neighboring cancer cells to promote typical DEK functions. This led to our hypothesis that DEK may be present in the plasma of cancer patients. In fact, the detection of DEK protein in urine is currently being explored as a diagnostic biomarker for bladder cancer. To test this hypothesis, we collected peripheral blood from patients with newly diagnosed, untreated BC (irrespective of the clinical stage) and age- and ethnicity-matched normal healthy controls. Plasma was separated from the samples and subjected to DEK specific ELISA (Cusabio, Wuhan, China). Preliminary results demonstrate that DEK is indeed present in the plasma of BC patients and we are currently comparing these levels to normal healthy controls. Further analyses are ongoing to determine whether DEK levels correlate with pertinent clinical and pathological variables including age, tumor stage, and ER/PR/HER-2 status. In addition, we are examining if DEK levels can predict response to various treatment modalities and risk of relapse. These data will be important to verify DEK plasma measurements as a clinically useful test and may give insight to future personalized and targeted treatment strategies for BC.

Citation Format: Arun Sendilnathan, Mahmoud Charif, Elizabeth Shaughnessy, Jaime D. Lewis, Neetu Radhakrishnan, Elyse Lower, Catherine Lanigan, Harriet Kumar, Trisha M. Wise-Draper, Lisa Privette Vinnedge. Investigation of the DEK oncogene as a blood biomarker for breast cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Breast Cancer Research; Oct 17-20, 2015; Bellevue, WA. Philadelphia (PA): AACR; Mol Cancer Res 2016;14(2_Suppl):Abstract nr A51.

Oncolytic virotherapy for head and neck cancer: current research and future developments

Head and neck cancer (HNC) is the sixth most common malignancy worldwide. Despite recent advancements in surgical, chemotherapy, and radiation treatments, HNC remains a highly morbid and fatal disease. Unlike many other cancers, local control rather than systemic control is important for HNC survival. Therefore, novel local therapy in addition to systemic therapy is urgently needed. Oncolytic virotherapy holds promise in this regard as viruses can be injected intratumorally as well as intravenously with excellent safety profiles. This review will discuss the recent advancements in oncolytic virotherapy, highlighting some of the most promising candidates and modifications to date.

DEK promotes HPV-positive and -negative head and neck cancer cell proliferation

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and patient outcomes using current treatments remain poor. Tumor development is etiologically associated with tobacco or alcohol use and/or human papillomavirus (HPV) infection. HPV-positive HNSCCs, which frequently harbor wild-type p53, carry a more favorable prognosis and are a biologically distinct subgroup when compared with their HPV-negative counterparts. HPV E7 induces expression of the human DEK gene, both in vitro and in vivo. In keratinocytes, DEK overexpression is sufficient for causing oncogenic phenotypes in the absence of E7. Conversely, DEK loss results in cell death in HPV-positive cervical cancer cells at least in part through p53 activation, and Dek knockout mice are relatively resistant to the development of chemically induced skin papillomas. Despite the established oncogenic role of DEK in HPV-associated cervical cancer cell lines and keratinocytes, a functional role of DEK has not yet been explored in HNSCC. Using an established transgenic mouse model of HPV16 E7-induced HNSCC, we demonstrate that Dek is required for optimal proliferation of E7-transgenic epidermal cells and for the growth of HNSCC tumors. Importantly, these studies also demonstrate that DEK protein is universally upregulated in both HPV-positive and -negative human HNSCC tumors relative to adjacent normal tissue. Furthermore, DEK knockdown inhibited the proliferation of HPV-positive and -negative HNSCC cells, establishing a functional role for DEK in human disease. Mechanistic studies reveal that attenuated HNSCC cell growth in response to DEK loss was associated with reduced expression of the oncogenic p53 family member, ΔNp63. Exogenous ΔNp63 expression rescued the proliferative defect in the absence of DEK, thereby establishing a functional DEK-ΔNp63 oncogenic pathway that promotes HNSCC. Taken together, our data demonstrate that DEK stimulates HNSCC cellular growth and identify ΔNp63 as a novel DEK effector.

Human papillomavirus induced transformation in cervical and head and neck cancers

Human papillomavirus (HPV) is one of the most widely publicized and researched pathogenic DNA viruses. For decades, HPV research has focused on transforming viral activities in cervical cancer. During the past 15 years, however, HPV has also emerged as a major etiological agent in cancers of the head and neck, in particular squamous cell carcinoma. Even with significant strides achieved towards the screening and treatment of cervical cancer, and preventive vaccines, cervical cancer remains the leading cause of cancer-associated deaths for women in developing countries. Furthermore, routine screens are not available for those at risk of head and neck cancer. The current expectation is that HPV vaccination will prevent not only cervical, but also head and neck cancers. In order to determine if previous cervical cancer models for HPV infection and transformation are directly applicable to head and neck cancer, clinical and molecular disease aspects must be carefully compared. In this review, we briefly discuss the cervical and head and neck cancer literature to highlight clinical and genomic commonalities. Differences in prognosis, staging and treatment, as well as comparisons of mutational profiles, viral integration patterns, and alterations in gene expression will be addressed.

The human DEK oncogene regulates DNA damage response signaling and repair

The human DEK gene is frequently overexpressed and sometimes amplified in human cancer. Consistent with oncogenic functions, Dek knockout mice are partially resistant to chemically induced papilloma formation. Additionally, DEK knockdown in vitro sensitizes cancer cells to DNA damaging agents and induces cell death via p53-dependent and -independent mechanisms. Here we report that DEK is important for DNA double-strand break repair. DEK depletion in human cancer cell lines and xenografts was sufficient to induce a DNA damage response as assessed by detection of γH2AX and FANCD2. Phosphorylation of H2AX was accompanied by contrasting activation and suppression, respectively, of the ATM and DNA-PK pathways. Similar DNA damage responses were observed in primary Dek knockout mouse embryonic fibroblasts (MEFs), along with increased levels of DNA damage and exaggerated induction of senescence in response to genotoxic stress. Importantly, Dek knockout MEFs exhibited distinct defects in non-homologous end joining (NHEJ) when compared to their wild-type counterparts. Taken together, the data demonstrate new molecular links between DEK and DNA damage response signaling pathways, and suggest that DEK contributes to DNA repair.

Overexpression of the cellular DEK protein promotes epithelial transformation in vitro and in vivo

High levels of expression of the human DEK gene have been correlated with numerous human malignancies. Intracellular DEK functions have been described in vitro and include DNA supercoiling, DNA replication, RNA splicing, and transcription. We have shown that DEK also suppresses cellular senescence, apoptosis, and differentiation, thus promoting cell growth and survival in monolayer and organotypic epithelial raft models. Such functions are likely to contribute to cancer, but direct evidence to implicate DEK as an oncogene has remained elusive. Here, we show that in line with an early role in tumorigenesis, murine papilloma formation in a classical chemical carcinogenesis model was reduced in DEK knockout mice. Additionally, human papillomavirus E6/E7, hRas, and DEK cooperated in the transformation of keratinocytes in soft agar and xenograft establishment, thus also implicating DEK in tumor promotion at later stages. Finally, adenoviral DEK depletion via short hairpin RNA expression resulted in cell death in human tumor cells in vitro and in vivo, but did not significantly affect differentiated epithelial cells. Taken together, our data uncover oncogenic DEK activities as postulated from its frequent up-regulation in human malignancies, and suggest that the targeted suppression of DEK may become a strategic approach to the treatment of cancer.

DEK proto-oncogene expression interferes with the normal epithelial differentiation program

Overexpression of the DEK gene is associated with multiple human cancers, but its specific roles as a putative oncogene are not well defined. DEK transcription was previously shown to be induced by the high-risk human papillomavirus (HPV) E7 oncogene via E2F and Rb pathways. Transient DEK overexpression was able to inhibit both senescence and apoptosis in cultured cells. In at least the latter case, this mechanism involved the destabilization of p53 and the decreased expression of p53 target genes. We show here that DEK overexpression disrupts the normal differentiation program in a manner that is independent of either p53 or cell death. DEK expression was distinctly repressed upon the differentiation of cultured primary human keratinocytes, and stable DEK overexpression caused epidermal thickening in an organotypic raft model system. The observed hyperplasia involved a delay in keratinocyte differentiation toward a more undifferentiated state, and expansion of the basal cell compartment was due to increased proliferation, but not apoptosis. These phenotypes were accompanied by elevated p63 expression in the absence of p53 destabilization. In further support of bona fide oncogenic DEK activities, we report here up-regulated DEK protein levels in both human papilloma virus-positive hyperplastic murine skin and a subset of human squamous cell carcinomas. We suggest that DEK up-regulation may contribute to carcinoma development at least in part through increased proliferation and retardation of differentiation.

Papillomavirus E6 and E7 proteins and their cellular targets

The mucosal human papillomaviruses (HPVs) infect human genital and oral epithelial cells and cause lesions ranging in severity from benign to malignant. HPV associated malignancies include cervical and other anogenital cancers as well as a subpopulation of head and neck cancers. Viral infection of epidermal stem or transit amplifying cells can result in long term viral persistence, and the development of carcinogenesis over a significant amount of time then requires additional cooperating genetic hits. Only the so-called high risk HPV types mediate human carcinogenesis, whereas the low risk HPVs have been linked to benign epithelial lesions that are not generally life threatening, but nonetheless are a major health burden. Expression of the high risk HPV E6 and E7 oncogenes is sufficient for primary human keratinocyte immortalization and is required for initiation and all subsequent stages of carcinogenic progression. Together with the finding that high levels of E6/E7 are a unifying hallmark of HPV positive cancers, these two genes are presumed to be the relevant virus-derived transformation stimuli in humans. E6 and E7 proteins do not possess intrinsic enzymatic activities, but instead function though a number of direct and indirect interactions with cellular proteins, a number of which are well known cellular tumor suppressors. We will summarize here current insights into E6 and E7 interactions with specific cellular targets that stimulate aspects of the viral life cycle, interfere with cell cycle controls and promote carcinogenic processes.