Neoadjuvant immunochemotherapy for locally advanced resectable oral squamous cell carcinoma: a prospective single-arm trial (Illuminate Trial)

BACKGROUND

Locally advanced oral squamous cell carcinoma (LAOSCC) is associated with a high rate of recurrence and poor survival. Given the recent successes of neoadjuvant immunochemotherapy (NAICT) in solid tumors, it is promising to use this treatment modality to achieve a better pathological response and improve the survival of LAOSCC, and clinical evidence is needed to assess its safety and efficacy.

PATIENTS AND METHODS

A prospective trial of NAICT with toripalimab (PD-1 inhibitor) and albumin paclitaxel/cisplatin (TTP) was conducted in patients with clinical stage III and IVA OSCC. Intravenous albumin paclitaxel (260 mg/m 2 ), cisplatin (75 mg/m 2 ), and toripalimab (240 mg) were given in sequence on day 1 of each 21 day cycle for two cycles, followed by radical surgery and risk-adapted adjuvant (chemo)radiotherapy. The primary endpoints were safety and major pathological response (MPR). Targeted next generation sequencing and multiplex immunofluorescence were performed to assess clinical molecular characteristics and the tumor immune microenvironment in the pre-NAICT and post-NAICT tumor samples.

RESULTS

Twenty patients were enrolled. NAICT was well-tolerated with a low incidence of grades 3-4 adverse events in three patients. The completion rates of NAICT and subsequent R0 resection were 100%. The MPR rate was 60%, including a 30% pathological complete response. MPR was achieved in all four patients with a combined positive score of PD-L1>10. The density of tertiary lymphatic structure in post-NAICT tumor samples predicted the pathological response to NAICT. During the median 23-month follow-up, the disease-free survival was 90%, and the overall survival was 95%.

CONCLUSIONS

NAICT with the TTP protocol in LAOSCC is feasible and well tolerated, with a promising MPR and no obstruction on subsequent surgery. This trial is supportive of further randomized trials using NAICT in LAOSCC.

Efficacy and feasibility of Apatinib and S-1 as a novel oral induction therapy in locally advanced head and neck squamous cell carcinoma: an exploratory phase 2 open-label, single-arm trial

Objectives

The current standard nonsurgical treatment for locally advanced head and neck squamous cell cancer (LA-HNSCC) is concomitant chemoradiotherapy (CRT). Neoadjuvant chemotherapy combined with CRT has been explored in HNSCC patients and is an acceptable strategy. However, the occurrence of adverse events (AEs) restricts its application. We conducted a clinical study to explore the efficacy and feasibility of a novel induction therapy with orally administered apatinib and S-1 in LA-HNSCC.

Materials and methods

This nonrandomized, single-arm, prospective clinical trial included patients with LA-HNSCCs. The eligibility criteria included histologically or cytologically confirmed HNSCC, with at least one radiographically measurable lesion detected by magnetic resonance imaging (MRI) or computerized tomography (CT) scan, age 18-75 years, and a diagnosis of stage III to IVb according to the 7^th edition of the American Joint Committee of Cancer (AJCC). Patients received induction therapy with apatinib and S-1 for three cycles (3 weeks/cycle). The primary endpoint of this study was the objective response rate (ORR) to induction therapy. The secondary endpoints included progression-free survival (PFS), overall survival (OS), and AEs during induction treatment.

Results

From October 2017 to September 2020, 49 patients with LA-HNSCC were screened consecutively and 38 were enrolled. The median age of the patients was 60 years (range, 39-75). Thirty-three patients (86.8%) had stage IV disease according to the AJCC staging system. The ORR after induction therapy was 97.4% (95% confidence interval [CI]: 86.2%-99.9%). the 3-year OS rate was 64.2% (95% CI: 46.0%-78.2%) and 3-year PFS was 57.1% (95% CI: 40.8%-73.6%). The most common AEs during induction therapy were hypertension and hand-foot syndrome, which were manageable.

Conclusion

Apatinib combined with S-1 as novel induction therapy for LA-HNSCC patients resulted in a higher-than-anticipated ORR and manageable adverse effects. With the associated safety profile and preferable oral administration route, apatinib combined with S-1 is an attractive exploratory induction regimen in outpatient settings. However, this regimen failed to show a survival benefit.

Clinical trial registration

https://clinicaltrials.gov/show/NCT03267121, identifier NCT03267121.

Can adjuvant radiotherapy be omitted for oral cavity cancer patients who received neoadjuvant therapy and surgery? A retrospective cohort study

BACKGROUND

Surgery and postoperative adjuvant therapy comprise the standard treatment for locally advanced resectable oral squamous cell carcinoma (LAROSCC), while preoperative neoadjuvant therapy is being explored without sufficient confirmation of improved survival. De-escalation regimens after neoadjuvant therapy, such as those omitting adjuvant radiotherapy, may provide comparable or better outcomes, suggesting rigorous assessment of adjuvant therapy outcomes is needed in LAROSCC patients. The authors thus performed this retrospective study in LAROSCC patients who received neoadjuvant therapy and surgery, to compare the outcomes for overall survival (OS) and locoregional recurrence-free survival (LRFS) between the adjuvant radiotherapy (radio) and nonradiotherapy (nonradio) cohorts.

MATERIALS AND METHODS

Patients diagnosed with LAROSCC who received neoadjuvant therapy and surgery were enrolled and divided into radio and nonradio cohorts to determine whether adjuvant radiotherapy could be omitted after neoadjuvant therapy and surgery.

RESULTS

From 2008 to 2021, 192 patients were enrolled. No significant differences were found in OS or LRFS between the radio and nonradio patient cohorts. The 10-year estimated OS rates were 58.9 versus 44.1% in radio versus nonradio cohorts, while 10-year estimated LRFS rates were 55.4 versus 48.2%, respectively. For clinical stage III patients, 10-year OS rates were 62.3 versus 62.6% (radio vs. nonradio), and estimated 10-year LRFS rates were 56.5 versus 60.7% (radio vs. nonradio). Multivariate Cox regression modeling of postoperative variables showed pathologic response of primary tumor and pathologic regional lymph nodes staging were associated with survival, while the adjuvant radiotherapy exposure was not included in the model due to nonsignificance.

CONCLUSION

These findings support further prospective evaluation of adjuvant radiotherapy omission, and suggest that de-escalation trials are warranted for LAROSCC surgery patients who received neoadjuvant therapy.

Adjuvant PD-1 Antibody in Recurrent, Previously Irradiated Oral Cavity Cancer Treated with Salvage Surgery

Objectives

The role of re-irradiation after salvage surgery for recurrent oral cavity cancer (OCC) is controversial. We evaluated the efficacy and safety of adjuvant toripalimab (PD-1 antibody) in this patient setting.

Materials and methods

In this phase II study, patients after salvage surgery with OCC occurring in an area of previously irradiated were enrolled. Patients received toripalimab 240 mg once every 3 weeks for 12 months, or combined with S-1 orally for 4-6 cycles. The primary endpoint was 1-year progression-free survival (PFS).

Results

Between April 2019 and May 2021, 20 patients were enrolled. Sixty percent patients had ENE or positive margins, 80% were restaged as stage IV, and 80% were previously treated with chemotherapy. The 1-year PFS and overall survival (OS) were 58.2%, and 93.8%, respectively, for patients with CPS ≥ 1, which was significantly better than those of the real-world reference cohort (p = 0.001 and 0.019). No grade 4-5 toxicities were reported, and only one patient experienced grade 3 immune related adrenal insufficiency and discontinued treatment. The 1-year PFS and OS were significantly different for patients with CPS < 1, CPS 1-19 and CPS ≥ 20 (p = 0.011 and 0.017, respectively). The peripheral blood B cell proportion was also correlated with PD in 6 months (p = 0.044).

Conclusion

Adjuvant toripalimab or combine with S-1 after salvage surgery showed improved PFS compared with a real-world reference cohort in recurrent, previously irradiated OCC, and favorable PFS were observed in patients with a higher CPS and peripheral B cell proportion. Further randomized trials are warranted.

Combined all-trans retinoic acid with low-dose apatinib in treatment of recurrent/metastatic head and neck adenoid cystic carcinoma: A single-center, secondary analysis of a phase II study

BACKGROUND

Treatment options are limited for recurrent/metastatic adenoid cystic carcinoma of the head and neck (R/M ACCHN). We aimed to evaluate the preliminary results of the efficacy and safety of all-trans retinoic acid (ATRA) combined with low-dose apatinib in patients with R/M ACCHN according to a secondary analysis of a phase II study.

METHODS

Patients from a phase II study (NCT02775370) who orally administered 500 milligram (mg) apatinib daily until treatment-related adverse events (AEs) intolerance or progression occurred were eligible for inclusion. Patients were further treated with combination therapy of ATRA (25 mg/m² /day) and apatinib (250 mg/day) between March 2019 and October 2021 until progression of disease (PD).

RESULTS

A total of 16 patients were included with nine (56.3%) males and aged 35-69 years old. All recruited patients previously received anti-angiogenic therapy then withdrew due to toxicities or progression occurred. The objective response rate (ORR) and disease control rate (DCR) were 18.8% and 100%, respectively. During a median follow-up of 23.9 months (range:17.8-31.7 months), 11 (68.8%) patients developed PD and one of them died in 20.9 months. The median of progression-free survival (PFS) was 16.3 months (95% CI: 7.2-25.4 months), and the 6-month, 12-month, and 24-month PFS rates were 100%, 81.3%, and 33.3%, respectively. The grade 3 adverse events were albuminuria (n = 2, 12.5%) and hand-foot syndrome (n = 1, 6.25%).

CONCLUSION

All-trans retinoic acid combined with low-dose apatinib might be a potential efficacy therapeutic option for patients with R/M ACCHN. This finding will be further confirmed by our registered ongoing trial, the APLUS study (NCT04433169).

Feasibility and quality of life of postoperative concurrent radiotherapy and toripalimab in elderly patients with head and neck squamous cell carcinoma (IMPORT trial)

6066

Background: For elderly patients with locally advanced head and neck squamous cell carcinoma (HNSCC), the role of postoperative concurrent chemotherapy was controversial since the intolerable toxicities and increased acute mortality, thus, radiotherapy alone was recommended. Aimed to seek out a feasible regimen for concurrent treatment, we evaluated the feasibility and quality of life of postoperative concurrent radiotherapy and toripalimab (anti-PD-1 antibody) in elderly HNSCC patients. Methods: The IMPORT trial was an investigator-initiated, multicentre, open-label, parallel-group, phase 2, randomized study. Patients were enrolled at 3 hospitals in China. We randomly assigned (1:1) patients aged＞65 years, with ECOG Performance Status(PS) of 0–2, and with postoperative Stage III-IV (AJCC 8th Staging system) HNSCC to concurrent radiotherapy (60-66Gy) and toripalimab (240mg on D0, D21 and D42)(RT+PD-1 group) or radiotherapy alone(RT group). Following stratification by PS(0-1 vs 2) and pathological adverse features (extranodal extension or positive margin vs others), patients were randomly assigned using a computer-generated randomization list. Acute toxicities were reported. Quality of life were evaluated by EORTC QLQ-C30 and QLQ-H&N35 at baseline, week3, week6 and 1 month after radiotherapy, and the standard scores were compared between groups by linear mixed-effects models. Results: Between September 2020 and December 2021, 38 patients randomly assigned(19 per group). The median age were 70 years (range 66-81) for the RT+PD-1 group and 73 years (range 67-78 years) for RT group. 16 (84.2%) patients in the RT+PD-1 group and 15 (78.9%) patients in the RT group complete the planed radiation dose. In the RT+PD-1 group, 13 (68.4%) patients completed 3 cycles of toripalimab, 3 (15.8%) patients completed 2 cycles due to adverse events and 3 (15.8%) patients declined toripalimab; The most common adverse events of grade 3-5 was oral mucositis (55.6% vs 58.8%) and lymphocyte count decreased(61.1% and 41.2%) in RT+PD-1 group and RT group. In the RT+PD-1 group, only 1 patients experienced grade 3 immune-related enteritis. As to the quality of life scores evaluated by QLQ-C30, no difference was found in standard score of global health status, as well as in most functional scales including: physical, emotion, cognitive and social, except for role functioning (p = 0.045). As to the symptom scale scores evaluated by QLQ-H&N35, no difference was found in standard score of pain, swallowing, dry mouth, opening mouth, and stick saliva, except for speech problem (p = 0.032). Conclusions: For elderly patients with locally advanced HNSCC, postoperative concurrent radiotherapy and toripalimab was safe and feasible. Concurrent toripalimab did not worsen quality of life scores in the majority of cases. Clinical trial information: NCT04523883.

Camrelizumab plus apatinib as induction therapy for locally advanced head and neck squamous cell carcinoma (IMplus): A single-arm phase II study

6060

Background: Immune checkpoint inhibitor combined with antiangiogenic agent has been investigated in many solid tumors, including advanced head and neck squamous cell carcinoma (HNSCC; NCT02501096), but the evidence is limited. This study was conducted to investigate the efficacy and safety of anti-programmed cell death-1 antibody camrelizumab plus antiangiogenic agent apatinib as induction therapy in patients with locally advanced HNSCC. Methods: In this single-center phase II trial (NCT04440917), patients with untreated locally advanced HNSCC who had inoperable lesions, could not tolerate surgery, or refused surgery were enrolled. Patients received camrelizumab 200 mg once every 2 weeks and apatinib 250 mg once daily for two 28-day cycles, followed by local treatment based on the re-examination results. The primary endpoint was objective response rate (ORR) after induction therapy, as assessed according to the Response Evaluation Criteria In Solid Tumors version 1.1. Simon’s two-stage design was adopted for this study. Results: Between December 2019 and July 2021, 18 patients were enrolled in the first stage. Eight (44%) patients had oropharyngeal carcinoma, nine (50%) had oral carcinoma, and one (6%) had hypopharyngeal carcinoma. There were six (33%), three (17%), and nine (50%) patients with stage III, IVA, and IVB disease, respectively. After induction therapy, six patients achieved complete response, nine achieved partial response, and three had stable disease, with an ORR of 83%. The study proceeded to the second stage and the enrollment for another 14 patients is ongoing. Two (11%) patients with partial response received surgery and adjuvant radiotherapy, and 16 (89%) received radical radiotherapy. With a median follow-up duration of 18 months (range, 9-26), only one disease recurrence and no deaths occurred. The most common adverse events during induction therapy were hypertension (ten [56%]), oral pain (nine [50%]), and increased aspartate aminotransferase (five [28%]). Only one [6%] grade 3 hypertension and one [6%] grade 3 proteinuria were observed, and no grade 4 or 5 adverse events occurred. Conclusions: Camrelizumab plus apatinib showed promising antitumor activity as induction therapy in patients with locally advanced HNSCC, with acceptable safety profile. Clinical trial information: NCT04440917.

EGFR Mutation and 11q13 Amplification Are Potential Predictive Biomarkers for Immunotherapy in Head and Neck Squamous Cell Carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignant cancers. The treatment of HNSCC remains challenging despite recent progress in targeted therapies and immunotherapy. Research on predictive biomarkers in clinical settings is urgently needed.

Methods

Next-generation sequencing analysis was performed on tumor samples from 121 patients with recurrent or metastatic HNSCC underwent sequencing analysis. Clinicopathological information was collected, and the clinical outcomes were assessed. Progression-free survival (PFS) was estimated using the Kaplan-Meier method and cox regression model was used to conduct multivariate analysis. Fisher’s exact tests were used to calculate clinical benefit. A p value of less than 0.05 was designated as significant (p < 0.05).

Results

Chromosome 11q13 amplification (CCND1, FGF3, FGF4, and FGF19) and EGFR mutations were significantly associated with decreased PFS and no clinical benefits after treatment with a programmed death 1 (PD-1) inhibitor. The same results were found in the combined positive score (CPS) ≥ 1 subgroup. In patients who were treated with an EGFR antibody instead of a PD-1 inhibitor, a significant difference in PFS and clinical benefits was only observed between patients with CPS ≥ 1 and CPS < 1.

Conclusion

Chromosome 11q13 amplification and EGFR mutations were negatively correlated with anti-PD-1 therapy. These markers may serve as potential predictive biomarkers to identify patients for whom immunotherapy may be unsuitable.

Screening, identification, purification and homologous modeling of marine cold-active alpha-amylase

BACKGROUND

Cold-active α-amylase is essential in industrial production. However, the number of cold-active α-amylases available for use is limited. Screening microbial strains would lay the groundwork for the future development of the food and pharmaceutical industries.

OBJECTIVE

To screen microbial strains for cold-active α-amylase based on physiological and biochemical identification, as well as homology modelling.

MATERIALS AND METHODS

Cold-active α-amylase strains were screened from water and mud obtained from the Yellow Sea. Colony morphology, Gram staining, scanning electron microscopy and transmission electron microscopy, physiological and biochemical identification and 16S rRNA gene analysis were used to identify strains. A series of steps, including DEAE-anion exchange column chromatography, SephadexG-100 column chromatography, and SDS-PAGE electrophoresis, were used to produce cold-active α-amylase of relatively high purity. Finally, the homology of amylase was modeled to explore the structure and activity site of the enzyme.

RESULTS

The named dsh19-1 strain of cold-active α-amylase was screened and identified as Bacillus. The cold-active α-amylase produced by Bacillus was named AmyD-1. The protein with PDB sequence number 5A2B was found to have 40.6% homology with AmyD-1. The verification score of the 3-D model was 137.07 points. We discovered that the six sites are potential sites for amylase to decompose starch by building a 3-D AmyD-1 model. AmyD-1 has a molecular weight of 1515 bp, and hydrogen bonding may be the primary interaction force between AmyD-1 and glucose molecules.

CONCLUSION

A cold-active α-amylase produced by Bacillus strain dsh19-1 was successfully obtained and named AmyD-1. This enzyme has potential uses in the food and pharmaceutical industries.

The Immune Landscape of Chinese Head and Neck Adenoid Cystic Carcinoma and Clinical Implication

Novel systemic agents and effective treatment strategies for recurrence adenoid cystic carcinoma (ACC) of the head and neck are still worthy of further exploration. Here, we analyzed the mutations and expression profiles of 75 Chinese ACC patients, characterized the prognostic value of the immune signature for recurrence or distant metastasis, and explored the potential of immunotherapeutic biomarkers in ACC. In general, MYB fusion and somatic mutations accounted for a high proportion, which was 46.7% (35/75). ACCs displayed an overall low mutation burden and lack of programmed cell death ligand-1 (PD-L1) expression. The antigen-presenting machinery (APM) expression score and immune infiltration score (IIS) were the lowest among ACC patients, compared with other cancer types. For 61 primary cases, the locoregional recurrence-free survival (LRRFS) was statistically significantly correlated with the IIS [univariate analysis; hazard ratio (HR) = 0.32; 95% CI, 0.11–0.92; p = 0.035] and T-cell infiltration score (TIS) (univariate analysis; HR = 0.33; 95% CI, 0.12–0.94; p = 0.037]. Patients with lower IIS (log-rank p = 0.0079) or TIS (log-rank p = 0.0079) had shorter LRRFS. Additionally, solid pattern was also a prognostic factor related to locoregional recurrence, whereas postoperative radiotherapy (PORT) exerted its beneficial effects. We further evaluated the pretreatment immune profile of five ACC patients treated with PD-1 inhibitors. Patients who responded to camrelizumab or pembrolizumab observed elevated APM and TIS, compared with patients with progressive disease. Our study highlights the immune infiltration pattern and messenger RNA (mRNA) signatures of Chinese ACC patients, which has the potential value for prognosis and immunotherapy.

[Interference of long noncoding RNA FOXCUT inhibits epithelial-mesenchymal transformation and induces mitochondrial injury in nasopharyngeal carcinoma cells]

OBJECTIVE

To investigate the effects of RNA interference of long noncoding RNA FOXCUT on epithelial mesenchymal transformation and mitochondrial function in nasopharyngeal carcinoma (NPC) cells.

METHODS

FOXCUT expression levels were detected by RT-PCR in tumor tissues and adjacent tissues from 50 patients with NPC and in NP69, CNE1, CNE2, SUNE2, HER2 and 5-8F cell lines. CNE1 cells were transfected with a short hairpin RNA (shRNA) targeting FOXCUT or a negative control RNA construct (shRNA-NC), and the changes in cell proliferation and morphology were assessed with CCK8 assay, clone formation assay and microscopic observation. An immunofluorescence assay was used to examine the vimentin-positive cells, and the levels of SOD, MDA and LDH in the cells were detected. The changes of mitochondrial membrane potential were detected with flow cytometry, and the expression levels of E-cad, N-cad, vimentin, Bax, Bcl-2, caspase-3 and c-Myc in the cells were detected with Western blotting.

RESULTS

The expression level of FOXCUT was significantly increased in NPC tissues as compared with the adjacent tissues (P < 0.001). Compared with NP69 cells, CNE1, CNE2, SUNE2, HER2 and 5-8F cells all exhibited significantly increased expressions of FOXCUT (P < 0.001). In CNE1 cells, transfection with FOXCUT shRNA significantly inhibited cell proliferation and clone formation (P < 0.001), and caused obvious changes in cell morphology. FOXCUT knockdown significantly decreased the expressions of N-cad and vimentin, increased E- cad expression and the contents of MDA and LDH (P < 0.05), reduced vimentin- positive cells and the activity of SOD, and caused a shift of red fluorescent cells to green fluorescent cells and an increased percentage of green fluorescent cells. FOXCUT knockdown also resulted in significantly increased expressions of Bax/Bcl2 and cleaved Cas3/Cas3 and a lowered expression of c-Myc.

CONCLUSIONS

Interference of FOXCUT can inhibit the proliferation and epithelial-mesenchymal transformation, enhance oxidative stress, induce mitochondrial function injury, and promote apoptosis in NPC cells, suggesting the potential of FOXCUT interference for targeted treatment of NPC.

Inductive camrelizumab and apatinib for patients with locally advanced and resectable oral squamous cell carcinoma: A single-arm trial (Icemelting trial)

6052

Background: In patients with locally advanced oral squamous cell carcinoma (LAOSCC), major pathologic response (MPR) to induction therapy may translate into improved survival. The induction therapy using chemo-free drugs, such as the combination of anti-PD1 and anti-VEGFR drugs, has not been well issued in LAOSCC. Methods: A prospective single arm trial (NCT04393506) has been performed to evaluate the induction therapy of anti-PD1 and anti-VEGFR protocol in LAOSCC patients at clinical stage III and IVA. The patients received three cycles of intravenous Camrelizumab (PD-1 antibody, 200mg) on d1, d15, d29; and oral Apatinib (anti-VEGFR inhibitor, 250mg) daily, initiating on d1, ending on the 5th day before surgery. Radical surgery was planned on d42-d45. Post-operative radiotherapy was planned within 1.5 months after surgery, based on clinical and pathological stage. The primary endpoints were MPR and safety; primary tumors were assessed for the percentage of residual viable tumor that was identified on HE staining, and tumors with no more than 10% viable tumor cells were considered as MPR. This study has been approved by institutional ethics committee at Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine. Results: From April to December 2020, 21 patients were enrolled in this trial, and one patient withdraw from the trial at the beginning of treatment. The induction therapy was well-tolerated with no grade 3-4 toxicity or serve induction therapy-related AEs. One patient required surgery delay for 7 days due to unexplainable cTnI elevation. One patient put off Camrelizumab for 14 days due to grade 2 thrombocytopenia. One patient suspended Apatinib for 21 days due to grade 2 Hyperbilirubinemia. The induction therapy did not effect on the subsequent standard treatment. MPR rate was 40% (8/20), including 5% (1/20) pCR. Radiological evaluation of response to induction therapy showed 3 PR, 10 SD, 5 PD and 2 NA. Weak correlation was found between pathologic and radiological evaluation on induction therapy. Combined positive score (CPS) of PD-L1 expression in biopsy was evaluated in 19 patients; all 4 patients with CPS≥ 20 had MPR, 3 out of 11 patients with 1≤CPS < 20 had MPR, and 1 out of 4 patients with CPS < 1 had MPR. Conclusions: The chemo-free protocol of induction therapy using Camrelizumab and Apatinib is safe and well-tolerated for the patients with LAOSCC. The MPR rate is much higher using the anti-PD1 and anti-VEGFR protocol than the traditional induction chemotherapy protocol in LAOSCC. Clinical trial information: NCT04393506.

Novel biomarkers for head and neck squamous cell carcinoma: A retrospective study

e18010

Background: PDL-1 and tumor mutation burden are only useful to select a small portion of patients with head and neck squamous cell carcinoma for immunotherapy, more biomarkers are in an urgent need for the majority. Methods: Ninety-nine recurrent/metastatic patients were analyzed. PD-1 cohort including 78 patients; Non-PD-1(NPD-1) cohort including 28 patients received anti-EGFR antibody and harbored at least one of EGFR amplification/mutation, CCND1 amplification, FGF3/4/19 amplification, or CDKN2A/B mutations (including 7 patients received with both treatment). Patients were evaluated as no clinical benefit (NCB) if experiencing progressive disease or stable disease lasting < 6 months and were discontinued from immunotherapy within 3 months; otherwise, patients were evaluated as clinical benefit (CB). Tumor genomic DNA was isolated from formalin-fixed paraffin-embedded tissue for the targeted sequencing by a 769-gene panel. R package was used for fisher test to evaluate the variants. p < 0.05 was set as significant. Results: With median age of 57 years old, this study included 75 (75.8%) oral squamous cell carcinoma patients,17 (17.2%) oropharyngeal carcinoma patients and 7 others. Sixty-nine (69.7%) patients have PD-L1 CPS≥1, 27 (27.3%) patients have CPS＜1 and 3 (3.0%) have an unknown CPS. The estimated 10-month progression-free survival of the NPD-1 cohort and PD-1cohort were 60.0%and 47.6% (p = 0.06) respectively. In NPD-1 cohort, 23 patients were evaluated as CB (78.3%), and in PD-1 cohort, 41 were evaluated as CB (52.6%) (p = 0.00682), indicating EGFR amplification/mutation, CCND1 amplification, FGF3/4/19 amplification, or CDKN2A/B mutations may be negatively correlated with immunotherapies. There were 14 patients who harbored either EGFR amplification or SNV mutation. Of the 8 patients who received NPD-1 treatment, 7 were CB (87.5%); Of the 8 patients who received PD-1 treatment, 2 were CB (25%) Statistically, the difference between NPD-1 treatment group and PD-1 treatment group was significant with a p value of 0.04056. There were 16 patients who harbored CCND1 amplification, or FGF3/4/19 amplification. Of the 12 patients who received NPD-1 treatment, 10 were evaluated as CB (83.3%); Of the 7 patients who received PD-1 treatment, 1 was evaluated as CB (14.3%). The difference was significant with a p value of 0.00627. There were 44 patients who obtained CDKN2A/B mutations. Of the 12 patients who received NPD-1 treatment, 11 acquired CB (81.7%); Of the 33 patients who received PD-1 treatment, 18 acquired CB (54.5%). The difference was significant with a p value of 0.03325. Conclusions: We for the first time showed that genetic-altered EGFR, FGF3/4/19, CCND1 and CDKN2A/B were negatively correlated with anti-PD-1 therapy in clinical cohorts retrospectively and these genetic aberrations may serve as novel immune-negative biomarkers for immunotherapies.

Adjuvant toripalimab or combined with S-1 in recurrent, previously irradiated head and neck squamous cell carcinoma treated with salvage surgery: A phase II clinical trial (The RePASS study)

6039

Background: The predominant pattern of failure for Head and Neck Squamous Cell Carcinoma (HNSCC) is locoregional disease. Salvage surgery remains the standard of care for operable disease. Re-irradiation after previous full course radiotherapy generally has been considered contraindicated. Since anti-PD-1 antibodies were efficacious and safety in recurrent/metastatic HNSCC, this study aimed to evaluate the efficacy and safety of adjuvant toripalimab (anti-PD-1 antibody) in recurrent, previously irradiated HNSCC treated with salvage surgery. Methods: This study was a single-arm, phase II study. Patients with HNSCC occurring in an area of previously irradiated and with at least one high risk factors after salvage surgery (1- positive margin; 2- extranodal extension; 3- rStaging T3-4/N2-3/T2N1) were enrolled. In the Stage I of 12 patients, patients received toripalimab 240mg once every 3 weeks until confirmed disease progression or unacceptable toxicity, for 12 months. In the stage II of 8 patients with PD-L1 CPS≥1, patients received toripalimab combined with S-1, which was given orally at 25 mg/m2, twice daily, on day 1 to 14, repeated every 21 days for 4-6 cycles. The primary endpoint was 1-year progression-free survival (PFS). We hypothesized a 1-year PFS of at least 56% and assumed a null hypothesis of 34%. A retrospective cohort of 16 patients was compared. Results: Between May 2019 and December 2020, 20 patients were enrolled. High-risk factors included ENE (35%), positive margin (25%), T3-4(30%) and T2N+(10%). Seventeen patients have PD-L1 CPS≥1 and 3 patients have CPS＜1. With a median follow-up of 11.2 months, estimated 1-year PFS and overall survival was 57.0% (95% confidence interval, 32%– 77%) and 79.2% (51%–91%). The primary PFS endpoint has exceeded the hypothesis and its median has not been reached. When compared to the retrospective cohort, the PFS was significantly better(p=0.001)，even for Stage I patients(Median PFS: 5.1 vs 3.7 months, p=0.03 ). Stage II patients resulted a better PFS and OS compare to stage I (p=0.02 and p=0.002). For patients with CPS≥1, 1-year PFS and OS was 79.1% (95% confidence interval, 51%–91%) and 91.7%(68%–99%), which were significantly better than patients with CPS＜1 (p=0.001 and p=0.05). Adjuvant Toripalimab or combine with S-1 was well-tolerated with no grade 3-4 toxicity and dose interruption as a result of treatment-related adverse event only occurred in 2 patients. Flow cytometry revealed that patients with short PFS had fewer baseline overall count of B cells(p=0.09). Conclusions: Adjuvant Toripalimab or combined with S-1 after salvage surgery is efficacious and safety in recurrent, previously irradiated HNSCC, and a better PFS was observed in patients treated with combined therapy and with CPS≥1. Further randomized trials are warranted. Clinical trial information: NCT04126460.

Apatinib in patients with recurrent or metastatic adenoid cystic carcinoma of the head and neck: a single-arm, phase II prospective study

Background

Apatinib, a vascular endothelial growth factor receptor (VEGFR) blocker, has demonstrated encouraging antitumor activities and tolerable toxicities in various cancer types. Recurrent or metastatic adenoid cystic carcinoma of the head and neck (R/MACCHN) carries a poor prognosis, and treatment options are currently limited. This study was conducted to explore the antitumor activity and safety of apatinib in patients with R/MACCHN.

Methods

In this phase II single-arm, prospective study, patients aged 15-75 years with incurable R/MACCHN received apatinib at a 500 mg dose once daily until intolerance or progression occurred. The primary endpoint was the 6-month progression-free survival (PFS) rate based on RECIST version 1.1. The secondary endpoints included response rate, overall survival (OS), and safety. Efficacy was assessed in all dosed patients with at least one post-baseline tumor assessment.

Results

Among 68 patients treated with apatinib, 65 were evaluable for efficacy analysis, with a median follow-up time of 25.8 months. The 6-month, 12-month, and 24-month PFS rates were 92.3% [95% confidence interval (CI): 83-97.5%], 75.2% (95% CI: 61.5-84.0%) and 44.7% (95% CI: 32.3-57.5%), respectively. The objective response rate (ORR) and disease control rate (DCR), as assessed by investigators, were 46.2% (95% CI: 33.7-59.0%) and 98.5% (95% CI: 91.7-100.0%), respectively. The median duration of response was 17.7 months [interquartile range (IQR) 14.0-20.9]. The 12-month and 24-month OS rates were 92.3% (95% CI: 83.0-97.5%) and 82.3% (95% CI: 70-90.4%), respectively. The most common adverse events of grades 3-4 were hypertension (5.9%), proteinuria (9.2%), and hemorrhage (5.9%). One patient developed a fatal hemorrhage.

Conclusion

An encouraging PFS, a high ORR, and a manageable safety profile were observed in this study. It seems that the administration of apatinib in R/MACCHN is likely to have a clinically meaningful therapeutic benefit and warrants further investigation.This study was prospectively registered in ClinicalTrials.gov (NCT02775370; date of registration: 17 May 2016; date of first patient enrollment: 25 May 2016).

Effect of oral supplements on the nutritional status of nasopharyngeal carcinoma patients undergoing concurrent chemotherapy: A randomized controlled Phase II trial

Objectives

The objectives of this study were to prospectively compare individualized dietary counseling with or without oral nutritional supplements (ONSs) in nasopharyngeal carcinoma (NPC) patients undergoing concurrent chemoradiotherapy (CCRT) in a Phase II, randomized trial.

Materials and Methods

Between June 2014 and August 2016, Stage II-IVb NPC patients were randomly enrolled. The primary endpoint was change in body weight between during CCRT, and the secondary endpoints were change in body mass index (BMI) and fat-free mass index (FFMI).

Results

Fifty-two patients were randomized; 19 patients in the control group and 23 in the ONS group were eligible for analysis. Weight, BMI, and body composition parameters significantly decreased from baseline to week 6. FFMI was significantly better in patients with ONS intake >2/3 planed than the control group (P = 0.028). Weight and BMI maintenance was slightly better in patients with total intake >2/3 planed (P = 0.170 and P= 0.229, respectively). The mean Patient-Generated Subjective Global Assessment score was also better in the ONS group at the end of CCRT (P = 0.053).

Conclusions

ONSs with individualized dietary counseling may be beneficial in patients with enough intake, and further prospective studies with large groups of patients are warranted.

Tumour immune characterization in adenoid cystic carcinoma identifies prognostic and immunotherapeutically relevant messenger RNA signatures

e15191

Background: Here, we profiled genetic hallmarks of Chinese adenoid cystic carcinoma (ACC) patients and immune cells infiltration levels by gene expression-based computational methods to investigate the correlation with immunotherapy. Methods: 54 patients with pathologically confirmed ACC admitted from January 2016 to October 2019 were included. Mutation and expression profiles were obtained by whole-exome sequencing (WES) and RNA-seq, respectively. A nomogram that integrated clinicopathological features with the immune signature to predict recurrence or distant metastasis probability was constructed by multivariate Cox regression. Results: As expected, we observed MYB fusion and somatic mutations in our cohort (57%, 31/54), strengthening the role of these aberrations as critical events in ACC. Mutations in NOTCH1 were also found in our cohort (19%, 10/54). Median tumour mutational burden (TMB) of these patients is 0.85 Muts/Mbp (0-11 Muts/Mbp). Analysis of WES data showed that all patients were microsatellite instability (MSI)-negative, and 17 of them were confirmed by conventional MSI-PCR testing. Lack of PD-L1 expression is 96.0% (n = 46/48) at a tumour proportion score 0% and 22.9% (11/48) of cases showed more than 10% CD8+ prevalence. We compared cancer types using an immune infiltration score (IIS) and an antigen presenting machinery expression (APM) score and find that ACC is among the lowest for both scores. Statistically significant correlations were found between IIS and distant metastasis-free survival (univariate analysis, HR = 2.64, 95% confidence interval [CI], 1.134 to 6.145, p = 0.023). Patients with higher IIS had shorter distant metastasis-free survival time (log-rank p = 0.020), and patients with higher T cell infiltration score (TIS) had shorter locoregional recurrence-free survival time (log-rank p = 0.050). In addition, we investigated the pretreatment immune profile of five ACC patients treated with PD-1 checkpoint inhibitors, and found that both TIS and APM were elevated in responding patient (with a partial response to camrelizumab) whereas they were in the lowest for patients with progressive disease on camrelizumab or pembrolizumab. Conclusions: Our study highlights the immune infiltration patterns and unravels mRNA signatures with prognostic utility and immunotherapeutic biomarker potential in ACC.

A Phase 2 Trial of Chemoradiation Therapy Using Weekly Docetaxel for High-Risk Postoperative Oral Squamous Cell Carcinoma Patients

PURPOSE

To evaluate the efficacy and safety of postoperative concurrent chemoradiation therapy using weekly docetaxel in patients with high-risk oral squamous cell carcinoma (OSCC).

METHODS AND MATERIALS

This is a prospective single-arm study from a single institute in Shanghai Ninth People's Hospital, Shanghai, China. Patients with locally stage III to IV OSCC who underwent radical surgery with at least 1 high-risk feature were enrolled for the study. High-risk features evaluated included (1) pathologically confirmed positive or close margins in the primary site or extracapsular nodal extension; (2) histologic involvement of ≥2 regional lymph nodes; and (3) locoregional recurrent OSCC (after initial surgery alone) treated with salvage surgery with curative intent. Docetaxel was administered at a dose of 20 mg/m² concurrently with postoperative radiation therapy (total dose 60-66 Gy). The primary outcome was 2-year disease-free survival (DFS). Secondary endpoints included 2-year locoregional progress-free survival, 2-year overall survival (OS), and toxicities.

RESULTS

From March 2016 to February 2018, 91 patients (59 males, 32 females) were recruited. Median age was 59 years (range, 26-70). All patients were included in final analysis. Fifty-eight patients (63.7%) completed the 6 planned cycles of docetaxel, and all patients completed postoperative radiation therapy. With a median follow-up of 24 months, the 2-year DFS and OS were 75.3% (95% confidence interval, 65.7%-84.2%) and 82.4% (95% confidence interval, 73.0%-89.6%), respectively. Patterns of failure were 13 local recurrences, 2 regional lymph nodes recurrences, and 8 distant failures. Seven patients (7.7%) were recorded as having grade 3 oral cavity mucositis. Two patients had grade 3 hypersensitivity reaction. No other grade 3 or higher adverse events, including hematologic toxicities, were observed.

CONCLUSIONS

The addition of low-dose weekly docetaxel with concurrent radiation therapy is a tolerable regimen with favorable DFS and OS in patients with high-risk, resected OSCC.

Long-term results of elective mucosal irradiation for head and neck cancer of unknown primary in Chinese population: The EMICUP study

Objective

Controversy still exists regarding the volume of radiation for head and neck cancer of unknown primary (HNCUP). Theoretically, elective mucosal irradiation (EMI) should achieve a balance between survival and toxicity. This prospective study was conducted to evaluate the long‐term benefit of EMI in Chinese HNCUP patients.

Methods

A phase II, single‐arm trial was performed at two centers in China. HNCUP patients with pathologically confirmed metastatic squamous cell carcinoma or poorly differentiated carcinoma were enrolled. Patients with metastatic lymph nodes limited to level IV and/or the supraclavicular fossa were excluded. The EMI approach was specifically customized to Chinese patients by differentiating HNCUP as putative nasopharyngeal carcinoma (NPC) or non‐putative NPC. The primary endpoint was 3‐year mucosal recurrence‐free survival (MRFS).

Results

A total of 48 patients were enrolled between 02/02/2010 and 08/01/2018; 46 patients were analyzed, including 24 putative NPC and 22 non‐putative NPC patients. No primary recurrence was observed during a median follow‐up period of 70 months, and only 1 patient experienced out of field recurrence in the contralateral neck. The 3‐year MRFS was 90.6% (95%CI: 76.4%‐96.4%). The 5‐year MRFS, regional‐recurrence free survival (RRFS) and overall survival (OS) were 90.6% (95%CI: 76.4%‐96.4%), 86.0% (95%CI: 71.1%‐93.7%), and 90.6% (95%CI: 76.4%‐96.4%), respectively. No grade 4 acute or late toxicities occurred, and the most frequent grade 3 acute toxicity was oral mucositis (45.7%).

Conclusion

To the best of our knowledge, this is the first prospective study to evaluate the long‐term outcomes of EMI in Chinese HNCUP patients. Excellent MRFS and OS rates were observed. Further randomized studies are warranted.

Longitudinal Body Composition Changes and the Importance of Fat-Free Mass Index in Locally Advanced Nasopharyngeal Carcinoma Patients Undergoing Concurrent Chemoradiotherapy

Aim: This was a prospective investigation of longitudinal body composition changes in patients with nasopharyngeal carcinoma undergoing concurrent chemoradiotherapy (CCRT) and a comparison of the Patient-Generated Subjective Global Assessment (PG-SGA) and the ESPEN (European Society for Clinical Nutrition and Metabolism) diagnostic criteria (EDC) as evaluation methods. Methods: All patients received standard CCRT according to 2 centers’ current practices. Body composition parameters were determined by bioelectrical impedance analysis and obtained weekly from baseline until the end of treatment. The nutritional status of all patients was evaluated by the PG-SGA and EDC. Results: Forty-eight patients were eligible for analysis. Most body composition parameters, including body cell mass, fat mass, fat-free mass, and skeletal mass, as well as body weight, body mass index, and PG-SGA score, significantly decreased during CCRT (P = .00). The PG-SGA was shown to have better sensitivity than the EDC; however, the 2 different evaluation methods were found to have a perfect concordance at Week 4 and Week 6 (κ = 0.91 and 0.96, P = .00 and .00, respectively). Pearson correlation analyses showed that fat-free mass index and body weight were positively correlated with global quality of life score (r = 0.81, P = .00; r = 0.78, P = .00, respectively). Conclusions: This study has shown that body composition parameters, especially fat-free mass index, are valuable for diagnosing malnutrition in patients with nasopharyngeal carcinoma receiving CCRT. We recommend that these bioelectrical impedance analysis techniques should be increasingly implemented in nutritional assessments.

A feasibility and safety study of concurrent chemotherapy based on genetic testing in patients with high-risk salivary gland tumors: Preliminary results

BACKGROUND

This prospective study was conducted to evaluate the feasibility and safety of customized chemotherapy regimens based on the gene characteristics of salivary gland tumors.

METHODS

Patients were enrolled with histologically confirmed intermediate or high grade, stage T3-4, N1-3 disease, and T1-2, N0 patients with a close (≤1 mm) or microscopically positive surgical margin were also enrolled in the study. All patients received radical surgery and postoperative concurrent chemoradiotherapy. To evaluate the responsiveness of therapies, the chemotherapy regimen was based on gene targets, β-tubulin III, ABCB1, STMN1, and CYP1B1 (for docetaxel) and TYMS (for pemetrexed). The primary endpoints were treatment compliance and acute toxicities.

RESULTS

A total of 20 patients were enrolled between September 2013 and January 2016. The median age was 46 years (range: 23-70 years). Genetic testing showed that 8 patients may have been sensitive to docetaxel, 5 patients may have been sensitive to pemetrexed, and 7 patients sensitive to either docetaxel or pemetrexed. All patients received the full dose of radiation. A total of 19 patients (95%) completed 2 cycles of concurrent chemotherapy (CCT). One patient treated concurrently with pemetrexed experienced grade 3 neutropenia. Three patients experienced grade 3 oral mucositis, and 2 patients experienced grade 3 dermatitis.

CONCLUSION

Our study demonstrated that a CCT selecting method based on the gene targets associated with drug sensitivity was clinically feasible and safe. Further studies enrolled more patients with longer follow-up times are needed to confirm the clinical efficacy of this CCT selecting method.

Tailored multimodality therapy guided by a two-step decision making process for head-and-neck cancer of unknown primary

Background

There is no consensus on the treatment of head-and-neck cancer of unknown primary (HNCUP). The objective of this study is to report our single institution's experience of a tailored multimodality therapy guided by a two-step decision making process.

Materials and Methods

From January 2007 to November 2013, 92 consecutive patients of HNCUP were treated. 77 patients were treated according the process above, 24 were treated by radiotherapy to the nasopharyngeal site, 7 received neck dissection and radiotherapy to other putative mucosal site, 30 were treated by neck dissection alone, and 16 received neck dissection followed by radiotherapy to the neck. SPSS 20.0 software was used for statistical analysis.

Results

After a median follow-up of 34 months, the 3-year overall survival rate was 84.5%. The 3-year mucosal control rate, neck control rate, distant metastasis-free survival rate and disease-free survival rate were 80.9%, 76.2%, and 92.0%, respectively. Of the 24 patients treated as putative nasopharyngeal carcinoma, no primary emerged from any site. Primary tumor emerged in 14 patients, and no primary emerged in the 31 patients treated with putative site radiation (3-year mucosal control rate: 100% vs. 67.9%, p = 0.010). Of the 46 patients treated with neck dissection with/without postoperative radiation, 14 developed neck recurrence, and patients without postoperative radiation suffered more ipsilateral neck recurrence.

Conclusions

The two-step decision-making process seem to be reasonable in treating Chinese HNCUP patients. However, this results need to be prospectively validated.

Ruminococcus gnavus E1 modulates mucin expression and intestinal glycosylation

AIMS

The molecular cross-talk between commensal bacteria and the gut play an important role in the maintenance of the intestinal homeostasis and general health. Here, we studied the impact of a major Gram-positive anaerobic bacterium of the human gut microbiota, that is, Ruminococcus gnavus on the glycosylation pattern and the production of intestinal mucus by the goblet cells.

METHODS AND RESULTS

Our results showed that R. gnavus E1 specifically increases the expression and the glycosylation level of the intestinal glyco-conjugates by goblet cells in the colonic mucosa of mono-associated mice with R. gnavus E1 as well as in human HT29-MTX cells. Such an effect was mediated through induction of the level of mRNA encoding for the major intestinal gel-forming mucin such as MUC2 and various glycosyltransferase enzymes.

CONCLUSIONS

This study demonstrates for the first time that R. gnavus E1 possess the ability to modulate the glycosylation profile of the glyco-conjugate molecules and mucus in goblet cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

Furthermore, we demonstrated that R. gnavus E1 modified specifically the glycosylation pattern and MUC2 expression by means of a small soluble factor of peptidic nature (<3 kDa) and heat stable in the HT29-MTX cell.

Tumor pretargeting in mice using MORF conjugated CC49 antibody and radiolabeled complimentary cMORF effector

AIM

Using the antiCEA antibody MN14, a LS174T mouse tumor model has been successfully targeted with (⁹⁹m)Tc for imaging and ¹⁸⁸Re for radiotherapy by phosphorodiamidate morpholino oligomers (MORF)/complementary MORF (cMORF) pretargeting strategy. This investigation evaluated the antiTAG-72 antibody CC49 as an alternative to MN14 for this application.

METHODS

Both CC49 and MN14 were labeled with ¹¹¹In via SCN-benzyl-DTPA and their biodistributions were compared to that of MN14 labeled via DTPA anhydride. Since the accessibility of the antibody to the effector is required for optimization of pretargeting, the internalization of both MORF-CC49 and MORF-MN14 antibodies in LS174T cells were evaluated in culture. In addition, the accessible concentration of MORF-CC49 antibody in tumor was determined in a series of pretargeting studies with escalating dosages of the [(⁹⁹m)Tc]cMORF effector. Finally, using these results and our semi-empirical model, an imaging study was performed under optimal pretargeting conditions.

RESULTS

The biodistribution of ¹¹¹In to trace the MN14 antibody depended significantly on the labeling method. Furthermore, both MORF-CC49 and MORF-MN14 antibodies showed rapid internalization in culture. Fortunately, the accessibility in tumor was found to be less seriously reduced in vivo. In a pretargeting study under optimal conditions, both by imaging and by necropsy, the [(⁹⁹m)Tc]cMORF effector accumulated predominantly in the tumor of pretargeted mice. Normal tissue accumulations were minimal except in kidneys, liver, and a segment of intestines.

CONCLUSION

MORF pretargeting with CC49 was equally successful in the LS174T tumor model to the MORF pretargeting with MN14. The MORF-CC49 antibody may therefore be considered for future investigations toward early clinical trials.

Dielectric scaling in polyelectrolyte solutions with different solvent quality in the dilute concentration regime

In this note, we present a set of radiowave dielectric spectroscopy measurements of two dilute, differently-charged polyelectrolyte solutions, under different solvent conditions. We have found that both the dielectric strength, Delta epsilon, and the relaxation time, tau(ion), of the dielectric relaxation process associated with the counterion polarization along a length scale of the order of the correlation length obey the scaling laws with the polyion concentration, according to the Ito model. This is verified with good accuracy independently of the quality of the solvent, which has been varied from poor to good solvent conditions. This finding supports evidence to the fact that, in dilute solutions, the counterion polarization is independent of the polyion concentration, in spite of what occurs at the semi-dilute concentrations.

Solvent quality influence on the dielectric properties of polyelectrolyte solutions: a scaling approach

The dielectric properties of polyelectrolytes in solvent of different quality have been measured in an extended frequency range and the dielectric parameters associated with the polarization induced by counterion fluctuation over some peculiar polyion lengths have been evaluated. Following the scaling theory of polyelectrolyte solutions and the recent models developed by Dobrynin and Rubinstein that explicitly take into account the quality of the solvent on the polyion chain conformation, we have reviewed and summarized a set of scaling laws that describe the dielectric behavior of these systems in the dilute and semidilute regime. Moreover, for poorer solvents, where theory of hydrophobic polyelectrolytes predicts, and computer simulation confirms, a particular chain structure consisting of partially collapsed monomers (beads) connected by monomer strings, we derived a scaling law. These predictions are compared with the results obtained from the dielectric parameters (the dielectric increment delta epsilon and the relaxation time tau(ion)) of the "intermediate" frequency relaxation of two partially charged polymers, which possess a carbon-based backbone for which water is a poor solvent and ethylene glycol is a good solvent. By varying the solvent composition (a water-ethylene glycol mixture), we have tuned the quality of the solvent, passing from poor to good condition and have observed the predicted scaling for all the systems investigated. These findings give a further support to the scaling theory of polyelectrolyte solutions and to the necklace model for hydrophobic polyelectrolytes in poor solvents.

Conductometric properties of linear polyelectrolytes in poor-solvent condition: The necklace model

We present a set of low-frequency electrical conductivity measurements of solutions of differently charged, salt-free polyelectrolytes in poor- and in good-solvent conditions, in the semidilute concentration regime. The data have been analyzed and discussed in light of the necklace model for hydrophobic polyelectrolytes recently proposed by Dobrynin et al. [Macromolecules 29, 2974 (1996)] that predicts the chains to collapse into spheroidal cores connected by narrow strings. By varying the quality of the solvent, we have measured the polyion equivalent conductance lambda(p) in an extended concentration range in the semidilute regime and have demonstrated that this parameter is influenced by the polyion chain conformation, giving further support, when the poor-solvent condition prevails, to the picture of a string of electrostatic blobs. On the contrary, in good-solvent condition, the electrical conductivity data are in reasonable good agreement with the picture of an extended chain consisting of a collection of electrostatic blobs. These electrical conductivity measurements, in light of scaling theory, furnish new experimental support for the necklace model for hydrophobic polyions in poor solvents.

Evidence of antisense tumor targeting in mice

Even though increased accumulations of radiolabeled antisense DNAs compared to control DNAs are becoming a routine observation in cultured tumor cells, trustworthy evidence of tumor targeting in vivo by an antisense mechanism remains elusive. The goal of this study was to obtain convincing evidence of antisense tumor targeting in nude mice by using two different tumors and both intratumoral (i.t.) and intravenous (i.v.) administration of radiolabeled antisense and control sense DNAs. Both the MDR++ cell line KB-G2 and its parent MDR+ cell line KB-31 were used in this study. The antisense (AS) DNA was directed against the AUG start codon of the MDR1 mRNA and, along with the sense (S) control DNA, was a uniform phosphorothioate administered naked. In previous cell culture studies from our laboratories, the accumulation of this AS DNA was strikingly high in KB-G2 cells and only average in KB-31 cells, a fact we attribute to the 1000-fold higher expression by RT-PCR of MDR1 mRNA in the former cell line. In this study, both DNAs were radiolabeled with (99m)Tc via MAG3 and administered i.t. or i.v. at 1 microg (100 microCi) per animal 24 h prior to sacrifice and dissection in mice bearing thigh tumors of about 1 g. Following i.t. administration, no statistically significant differences (Student's t test, p < 0.05, N = 4) between the AS and S DNA biodistributions in normal tissues were observed except in the KB-G2 mice in which muscle levels were lower for the S control. In contrast, tumor levels in the KB-G2 animals were significantly higher for the AS DNA vs S DNA (14.7 vs 8.5% ID/g) while this difference (8.6 vs 4.3% ID/g) was insignificant in the KB-31 animals. The whole body images obtained just prior to sacrifice clearly show improved targeting of AS DNA vs S DNA in the KB-G2 but not the KB-31 animals. Calculations based on these results show that about 60 000 AS DNAs accumulated specifically (i.e. AS DNA - S DNA) per KB-G2 tumor cell following i.t. administration. When administered i.v. rather than i.t., higher tumor levels in KB-G2 animals compared to KB-31 were not observed, most likely because of the lower dosage reaching the tumors. When the KB-G2 and KB-31 results are combined, no statistically significant differences between the AS and S DNA biodistributions in normal tissues were observed except in blood in which S DNA levels were higher and in spleen in which they were lower. In contrast, tumor levels were significantly higher for the AS DNA vs S DNA (0.100 vs 0.063% ID/g). Calculations based on these results show that about 400 AS DNAs accumulated specifically per tumor cell following i.v. administration. Therefore evidence for tumor targeting in vivo by an antisense mechanism has been obtained in that statistically higher tumor accumulations of the (99m)Tc-AS DNA were observed compared to the control (99m)Tc-S DNA both following i.t. and i.v. administrations. The successful localization of AS DNA in tumor demonstrates that in vivo AS targeting of tumor is feasible although improvements in tumor delivery and normal tissue clearance are needed for practical antisense imaging.

5' dinucleotide repeat polymorphism of NRAMP1 and susceptibility to tuberculosis among Caucasian patients in Houston, Texas

SETTING

Houston Tuberculosis Initiative (HTI) and Baylor College of Medicine, Houston, Texas.

OBJECTIVE

To further explore the association between the polymorphisms of NRAMP1 and human susceptibility/resistance to tuberculosis (TB), specifically to determine whether the reported association shown for blacks and Asians holds true for Caucasian populations.

DESIGN

In a case-control study, 135 adult Caucasian TB patients and 108 adult Caucasian HIV-seronegative non-TB controls were analyzed for the association between the polymorphisms in NRAMP1 gene and clinical TB.

RESULTS

Heterozygote at 5'(GT)n, a dinucleotide repeat polymorphism in the promoter of NRAMP1, was observed at significantly higher frequencies among HIV-negative patients with pulmonary TB (41.6%; OR 2.02; 95%CI 1.11-3.64), extra-pulmonary TB (66.7%; OR 4.80; 95%CI 1.34-17.15), and HIV-seropositive TB patients (50%; OR 3.77; 95%CI 1.33-10.66) in comparison with the controls (27.8%). Homozygotes (GT)(10,10) were over-represented among HIV-positive TB patients (18.2%; OR 6.86; 95%CI 1.55-30.21) compared to the controls (5.5%).

CONCLUSION

These findings suggest that the 5'(GT)n polymorphism of NRAMP1 modifies TB susceptibility in this Caucasian population, and could possibly be related to the site of infection among HIV-negative individuals and HIV-coinfected TB.

[MRI diagnosis of painful ophthalmoplegia syndrome]

OBJECTIVE

To study MRI appearances of painful ophthalmoplegia syndrome and provide image basis for clinical diagnosis of painful ophthalmoplegia syndrome.

METHODS

Seventeen cases with painful ophthalmoplegia syndrome diagnosed clinically were collected. MRI ordinary scan and gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) contrast fatty-restraint scan were performed on the orbit and cavernous sinus.

RESULTS

MRI appearances of painful ophthalmoplegia syndrome included patch or small nodule abnormal signal at the region of fissura orbitalis superior. The ipsilateral cavernous sinus was enlarged. The local lobus temporalis meninges close to the fissura orbitalis superior and cavernous sinus were invaded. MRI contrast fatty-restraint scan might clearly show the pathological changes.

CONCLUSION

MRI may provide image basis for the clinical diagnosis of painful ophthalmoplegia syndrome.

Expression of bright at two distinct stages of B lymphocyte development

The B cell regulator of Ig heavy chain transcription (Bright) is a DNA-binding protein that was originally discovered in a mature Ag-specific B cell line after stimulation with IL-5 and Ag. It binds to the intronic heavy chain enhancer and 5' of the V1 S107 family V(H) promoter. Several studies suggested that Bright may increase transcription of the heavy chain locus, and expression in cell lines was limited to those representing mature B cells. We have now analyzed normal hemopoietic tissues for the expression of Bright during B lymphocyte differentiation. We expected to find Bright expression in a subset of mature spleen cells, but also observed Bright in a subset of normal B lymphocytic progenitors in both adult bone marrow (BM) and in fetal liver as early as day 12 of gestation. Bright was also expressed in the small percentage of CD4(low) cells in the thymus that are newly arrived from the BM and are not yet committed to the T lymphocyte lineage, but was not observed at later stages of T cell differentiation in either the spleen or thymus. Bright mRNA was not detected in the immature B lymphocytes that initially populate the spleen after migration from the BM. In addition, new splice variants of Bright were observed in fetal tissues. Thus, Bright expression is highly regulated in normal murine lymphocytes and occurs both early and late during B cell differentiation. These findings may have important implications for the function of Bright in regulating Ig transcription.

Family-specific differences in transcription efficiency of Ig heavy chain promoters

Murine Ig variable region heavy chain genes (V(H)) are grouped into families based on coding sequence homology. We observed that the accompanying promoter sequences were also conserved in a family-specific manner. Remarkably, no one has directly compared the transcription efficiencies of V(H) genes from different families. Using an in vitro transcription system, we found that transcription efficiencies of different V(H) promoters differed by as much as 70-fold. These differences could be attributed to variation in the octamer-heptamer and TATA sequences, as well as to the presence or absence of initiator elements. The J558 family promoter exhibited the highest level of transcription and specifically interacted with an Oct-1 dimer not bound by other V(H) promoters. These data suggest that differential transcription and regulation of V(H) promoters could occur in vivo. The increased transcription efficiency of the J558 promoter relative to other V(H) promoters also presents a possible explanation for the abundance of J558 sterile transcripts observed before V(H)DJ(H) rearrangement.

Family-specific differences in transcription efficiency of Ig heavy chain promoters

Murine Ig variable region heavy chain genes (V(H)) are grouped into families based on coding sequence homology. We observed that the accompanying promoter sequences were also conserved in a family-specific manner. Remarkably, no one has directly compared the transcription efficiencies of V(H) genes from different families. Using an in vitro transcription system, we found that transcription efficiencies of different V(H) promoters differed by as much as 70-fold. These differences could be attributed to variation in the octamer-heptamer and TATA sequences, as well as to the presence or absence of initiator elements. The J558 family promoter exhibited the highest level of transcription and specifically interacted with an Oct-1 dimer not bound by other V(H) promoters. These data suggest that differential transcription and regulation of V(H) promoters could occur in vivo. The increased transcription efficiency of the J558 promoter relative to other V(H) promoters also presents a possible explanation for the abundance of J558 sterile transcripts observed before V(H)DJ(H) rearrangement.

Reassessment of germline heavy chain transcripts from two murine VH families

While expression of functional heavy chain immunoglobulin mRNA requires rearrangement of variable (VH), diversity (D) and (JH) gene segments, these individual gene segments can be transcribed prior to their rearrangement. It has been proposed that the resulting germline, or sterile, transcripts play an important role in the rearrangement process because strong correlations between rearrangement frequency and sterile transcript levels have been observed in some studies. Murine VH genes have been grouped into families on the basis of coding sequence homology. VH families rearrange in a developmentally regulated manner, so that rearrangements of genes from several VH families are detected earlier than rearrangements of J558 family genes. Paradoxically, the only VH family for which sterile transcripts have been documented is the J558 family. We used RT-PCR analyses to ask whether sterile transcripts from other VH families could be detected in fetal liver samples prior to their rearrangement. While J558 family germline transcripts were easily detected, no sterile transcripts were observed from the S107 family. Our studies also revealed the ability of small quantities of degraded genomic DNA to nonspecifically prime cDNA synthesis, emphasizing the need for caution in interpreting RT-PCR data in which family-specific oligos are used for cDNA production. These results cast doubt on the idea that sterile transcripts are required for V(H)DJ(H) rearrangement.

The recombination signal sequence-binding protein RBP-2N functions as a transcriptional repressor

We have identified a cellular protein, RBP-2N, a presumed recombinase, as a repressor of transcription. Inhibition of transcription by RBP-2N was dependent on its DNA recognition site and was demonstrated in vitro and in vivo. This repression appears to be general, as transcription mediated by SP1 and Gal4/VP16 was inhibited by RBP-2N. The protein was purified to near homogeneity from human cells on the basis of its binding to a site present in the promoter of the adenovirus pIX gene. The DNA recognition sequence is 5'-TGGGAAAGAA, which is markedly different from the recombination signal sequence originally identified as the target site for this protein. The sequence of the purified protein is 97% identical with that published for the mouse RBP-2N protein. The reported homolog in Drosophila is Suppressor of Hairless. RBP-2N binding sites are present in a number of cellular and viral promoters, so RBP-2N may have a general role in transcriptional repression.

Single missense mutation in the tyrosine kinase catalytic domain of the RET protooncogene is associated with multiple endocrine neoplasia type 2B

Multiple endocrine neoplasia type 2B (MEN 2B) is a human cancer syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytomas, mucosal neuromas, ganglioneuromas of the intestinal tract, and skeletal and ophthalmic abnormalities. It appears both as an inherited disorder and as de novo disease. Sequence analysis of germ-line DNA from MEN 2B patients revealed the existence of the same point mutation in the RET protooncogene in 34 unrelated individuals. This sequence difference was not observed in 93 unaffected individuals, including the normal parents of 14 de novo MEN 2B patients. The mutation (ATG-->ACG) results in the replacement of methionine with threonine within the catalytic core region of the tyrosine kinase domain. We propose that this amino acid replacement effects substrate interactions and results in dominant oncogenic activity by the RET protein. Missense mutations in the extracellular ligand-binding domain of the RET protooncogene previously have been associated with two other disorders [MEN 2A and familial MTC (FMTC)] in which MTC is observed. MEN 2B represents the third form of heritable MTC known to be an allele of RET. Alterations in two different functional domains of the putative receptor protein tyrosine kinase are implicated in development of MTC.

Mutations in the RET proto-oncogene are associated with MEN 2A and FMTC

Multiple endocrine neoplasia type 2A (MEN 2A) and familial medullary thyroid carcinoma (FMTC) are dominantly inherited conditions which predispose to the development of endocrine neoplasia. Evidence is presented that sequence changes within the coding region of the RET proto-oncogene, a putative transmembrane tyrosine kinase, may be responsible for the development of neoplasia in these inherited disorders. Single strand conformational variants (SSCVs) in exons 7 and 8 of the RET proto-oncogene were identified in eight MEN 2A and four FMTC families. The variants were observed only in the DNA of individuals who were either affected or who had inherited the MEN2A or FMTC allele as determined by haplotyping experiments. The seven variants identified were sequenced directly. All involved point mutations within codons specifying cysteine residues, resulting in nonconservative amino acid changes. Six of the seven mutations are located in exon 7. A single mutation was found in exon 8. Variants were not detected in four MEN 2B families studied for all exon assays available, nor were they detectable in 16 cases of well documented sporadic medullary thyroid carcinoma or pheochromocytoma that were tested for exon 7 variants. Coinheritance of the mutations with disease and the physical and genetic proximity of the RET proto-oncogene provide evidence that RET is responsible for at least two of the three inherited forms of MEN 2. Neither the normal function, nor the ligand of RET are yet known. However, its apparent involvement in the development of these inherited forms of neoplasia as well as in papillary thyroid carcinoma suggest an important developmental or cell regulatory role for the protein.