SETD2 Deficiency Confers Sensitivity to Dual Inhibition of DNA Methylation and PARP in Kidney Cancer

SETD2 deficiency alters the epigenetic landscape by causing depletion of H3K36me3 and plays an important role in diverse forms of cancer, most notably in aggressive and metastatic clear-cell renal cell carcinomas (ccRCC). Development of an effective treatment scheme targeting SETD2-compromised cancer is urgently needed. Considering that SETD2 is involved in DNA methylation and DNA repair, a combination treatment approach using DNA hypomethylating agents (HMA) and PARP inhibitors (PARPi) could have strong antitumor activity in SETD2-deficient kidney cancer. We tested the effects of the DNA HMA 5-aza-2'-dexoxydytidine (DAC), the PARPi talazoparib (BMN-673), and both in combination in human ccRCC models with or without SETD2 deficiency. The combination treatment of DAC and BMN-673 synergistically increased cytotoxicity in vitro in SETD2-deficient ccRCC cell lines but not in SETD2-proficient cell lines. DAC and BMN-673 led to apoptotic induction, increased DNA damage, insufficient DNA damage repair, and increased genomic instability. Furthermore, the combination treatment elevated immune responses, upregulated STING, and enhanced viral mimicry by activating transposable elements. Finally, the combination effectively suppressed the growth of SETD2-deficient ccRCC in in vivo mouse models. Together, these findings indicate that combining HMA and PARPi is a promising potential therapeutic strategy for treating SETD2-compromised ccRCC.

SIGNIFICANCE

SETD2 deficiency creates a vulnerable epigenetic status that is targetable using a DNA hypomethylating agent and PARP inhibitor combination to suppress renal cell carcinoma, identifying a precision medicine-based approach for SETD2-compromised cancers.

Overview, Diagnosis, and Perioperative Systemic Therapy of Upper Tract Urothelial Carcinoma

Upper tract urothelial carcinoma comprises 5-10% of all urothelial carcinoma cases. This disease tends to have a more aggressive course than its lower urinary tract counterpart, with 60% of patients presenting with invasive disease and 30% of patients presenting with metastatic disease at diagnosis. The diagnostic workup of UTUC involves imaging with CT urogram, urine cytology, and direct visualization and biopsy of suspected lesions via ureteroscopy. Standard treatment of high-grade UTUC involves radical nephroureterectomy (RNU) and excision of the ipsilateral bladder cuff. Both the NCCN and EAU Guidelines include neoadjuvant chemotherapy as a treatment option for select patients with UTUC; however, there are no strict guidelines. Much of the rationale for neoadjuvant chemotherapy is based on extrapolation from data from muscle-invasive bladder cancer, which has demonstrated a 5-year OS benefit of 5-8%. Retrospective studies evaluating the use of NACT in urothelial carcinoma have yielded pathologic objective response rates of 48% in UTUC cohorts. The randomized Phase III POUT study noted a DFS advantage with adjuvant platinum-based chemotherapy, compared with surveillance in UTUC, of 70% vs. 51% at 2 years. Though not the standard of care, multiple studies have explored the use of perioperative immunotherapy or chemoimmunotherapy in the management of invasive urothelial carcinoma. The PURE-02 study explored the use of neoadjuvant pembrolizumab in patients with high-risk UTUC. A small study of 10 patients, it showed no significant signals of activity with neoadjuvant pembrolizumab. Another Phase II study of neoadjuvant ipilimumab and nivolumab in cisplatin-ineligible UTUC yielded more promising findings, with 3/9 patients attaining a pathologic CR and the remaining six pathologically downstaged. The ABACUS trial found a 31% pathologic complete response rate amongst cisplatin-ineligible MIBC patients treated with neoadjuvant atezolizumab. The use of adjuvant immunotherapy has been explored over three phase III trials. The CheckMate-274 trial found a DFS benefit with the addition of one year of adjuvant nivolumab in patients with high-risk urothelial carcinoma. The IMvigor-010 study of adjuvant atezolizumab was a negative study. The AMBASSADOR trial of adjuvant pembrolizumab is pending results. With the FDA approval of erdafitinib in metastatic urothelial carcinoma, similar targets have been explored for use in perioperative use in invasive urothelial carcinoma, as with adjuvant infigratinib in the PROOF-302 trial. As the treatment paradigm for urothelial carcinoma evolves, further prospective studies are needed to expand the perioperative treatment landscape of UTUC.

Integration of Liquid Biopsies in Clinical Management of Metastatic Prostate Cancer

PURPOSE OF REVIEW

The field of liquid biopsies is constantly evolving through novel technologies. This review outlines current data on liquid biopsies and application to clinical management of metastatic prostate cancer.

RECENT FINDINGS

To date, there are three platforms with FDA approval for use in the setting of metastatic prostate cancer and others which have been clinically validated. There is substantial evidence supporting the use of circulating tumor cell (CTC) enumeration to guide prognosis in metastatic castration-resistant prostate cancer (mCRPC). Additional evidence supports targeted sequencing of CTC and cell-free DNA (cfDNA) to guide androgren-directed therapy, identify candidates for treatment with PARP inhibitors, and monitor development of resistance. As a real-time and minimally invasive approach, utilization of liquid biopsies has the potential to drastically impact the treatment of metastatic prostate cancer and improve overall survival. With further clinical validation, additional liquid biopsy is likely to enter standard clinical practice.

Impact of steroid use among patients with renal cell carcinoma (RCC) who develop immune-related adverse events (irAE)

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Background: Immune checkpoint inhibitor (ICI) therapy has become a standard therapy in the treatment of advanced renal cell carcinomas (RCC). This has led to a proportional increase in the frequency of immune related adverse events (irAE), however. While increasing evidence suggests that irAE may be correlated with benefit from ICI, the impact of steroids to mitigate irAE’s remains unclear. Methods: We analyzed records of patients with RCC treated with an ICI at the USC Norris Comprehensive Cancer Center, Keck Hospital of USC, and LAC+USC Hospital from 2015-2021. Statistical analysis was performed using R. The Kaplan-Meier model was used to calculate progression free survival (PFS) and overall survival (OS). A log-rank test was used to determine if differences in PFS/OS were statistically significant. Results: Out of a total 841 cancer patients treated with ICI, 107 RCC patients were identified. The median age was 60 (range 20-91). The two most common represented ethnicities were 48 Hispanic/Latino (44.9%) and 37 Caucasian (34.6%). The patient population include 64 male patients (59.8%) versus 43 female patients (40.2%). Most had metastatic disease (74.8%) versus local disease (25.2%), and most patients (80.4%) received ICI therapy as initial therapy. Only 6 patients (5.6%) were given combination ICI therapy. The three most common systems affected by irAE were endocrine (18.7%), dermatologic (16.8%), and renal (14.0%). Of the irAE that occurred, 21.5% were categorized as CTCAE grade III or higher. The median PFS of the irAE group was 51.8 months (95% CI 10.0 – 51.8) versus 11.2 months (95% CI 2.7 – 13.8) in the no irAE group. The median OS of the irAE group was 55.0 months (95% CI 23.9 – 55.0) versus 15.6 months (95% CI 13.5 – 23.5). The occurrence of irAE was associated with both statistically significantly increased PFS (p = 0.02) and OS (p = 0.007). The median PFS of patients receiving steroids to treat irAE was 6.5 months (95% CI 3.9 – 9.2) compared to 12.5 months (95% CI 10.4 – 12.5) in the group with irAE who did not receive steroids. The use of steroids was associated with statistically significant worse PFS (p = 0.04) and worse OS but not at statistical significance (p = 0.2). Conclusions: The occurrence of irAE was associated with improved PFS and OS in RCC patients treated with ICI. Furthermore, the use of steroids among patients with irAE was associated with worsened PFS, but not OS. Although steroids should still be used as clinically indicated for the management of irAE, clinicians should be judicious as they may blunt tumor response to ICI treatment.

Albumin levels predict prognosis in advanced renal cell carcinoma treated with tyrosine kinase inhibitors: a systematic review and meta-analysis

PURPOSE

With the development of therapy and prognostic criteria for metastatic Renal Cell Carcinoma (mRCC), the prognostic value of serum albumin level has remained in dispute. The aim of this meta-analysis was to evaluate the role of pre-treatment albumin in predicting the prognosis of mRCC patients in the era of tyrosine kinase inhibitor (TKI) treatments.

METHODS

The qualitative and quantitative synthesis was conducted of studies retrieved from PubMed, Embase, and Cochrane library from inception of these databases to July 19, 2020. The hazard ratio (HR) and its 95% confidence interval (CI) of overall survival (OS) and progression-free survival (PFS) were extracted from studies comparing different levels of pre-treatment serum albumin (as a dichotomous or continuous variable) in mRCC patients treated with TKI agents.

RESULTS

Within 5,638 primitive records, 16 were eligible and 14 had adequate data for quantitative analysis (N = 2,863 participants). Random-effects meta-analysis showed that lower albumin was related to poorer OS (dichotomous: HR = 2.01, 95% CI: 1.64-2.46, P < 0.001, I² = 28.8%; continuous: HR =0.93, 95% CI: 0.86-1.00, P = 0.040, I² = 67.5%) and PFS (dichotomous: HR = 1.45, 95% CI: 1.04-2.01, P = 0.029, I² = 57.4%; continuous: HR = 0.89, 95% CI: 0.80-0.98, P = 0.023, I² = 93.3%).

CONCLUSION

Lower pre-treatment serum albumin level is an independent adverse predictor of prognosis of mRCC patients receiving TKI therapy.

REGISTRATION

PROSPERO ID: CRD42020196802 Sep. 2^nd, 2020.

A Case Series of Multiple Primary Malignancies Among Patients With Advanced Melanoma

Multiple primary malignancies (MPM) are described as two or more primary tumors within the same individual. The impact of MPM on the tumor microenvironment among patients with melanoma is poorly understood. Here, we describe this unique group of patients who have both advanced melanoma and at least one other primary malignancy and report their survival outcomes. In this study, patients with advanced melanoma and a second primary malignancy were identified. Medical records were reviewed for cancer treatment history. Kaplan-Meier methods were used to derive survival curves and estimate overall survival (OS), and log-rank tests were used to compare OS. Among 11 MPM patients, the most common non-melanoma cancers were breast (n = 3) and thyroid (n = 3). Median OS was 153.5 months for all patients. Median OS for synchronous MPM (sMPM) and metachronous MPM (mMPM) were 83.1 and 196.7 months, respectively (p= 0.10). Median OS was not reached when melanoma was diagnosed first, and 153.5 months when diagnosed second (p= 0.45). For six patients receiving immunotherapy for melanoma, there was a 100% complete response rate. In conclusion, patients with melanoma are at risk of secondary malignancies, including breast and thyroid cancer. The timing of secondary malignancies may impact prognosis. Further study of the impact of immunotherapy on MPM is warranted.

Assessing somatic and germline variants in cancer patients

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Background: The increasing integration of somatic and germline testing into oncology practice allows physicians to target oncologic therapy and identify those with cancer predisposition. We explored the impact of a somatic assay (liquid biopsy, LB) on the identification of patients appropriate for germline genetic testing. Methods: We identified a cohort of diverse cancer patients with LB to assess for targetable somatic gene variants at LAC+USC Medical Center between 2016 and 2020 (n= 467). To enrich the cohort for variants that may reflect germline findings, we focused on the 46 patients (9.9%) who had at least one variant identified with a cell-free DNA (cfDNA) fraction of 25.00% or greater. Retrospective chart review extracted demographics and medical history with variables related to cancer history and treatment. LB variants were classified based on whether germline confirmation was indicated and the results of germline tests, when done, were reviewed. Results: Table summarizes the characteristics of the 46 patients identified to have at least one variant on LB in ≤ 25% of the cfDNA. The most frequently mutated genes on LB were TP53 (n=18, 39%), KRAS (n=11, 24%), APC (n=8, 17%), BRCA2 (n=7, 15%), PIK3CA (n=6, 13.0%), and BRCA1 (n=4, 9%). Seventeen patients (40%) were referred for genetic counseling and 13 (30%) underwent germline testing of whom 10 (77%) carried pathogenic variants (PV). All germline PV were concordant with LB variants identified. Four patients with PV BRCA2 on LB and confirmed to be germline, had lung or biliary tract diagnoses, which are not part of the typical BRCA-tumor spectrum. Thirty-three patients were not referred for genetic counseling, though 24 (72%) had LB-identified variants in cancer predisposition genes and 18 (54%) merited a genetics referral. Among patients with germline mutations, three (23%) had targeted therapy and two (15%) had preventive surgery to address second primary cancer risk. Among the 467 patients with LB results, there were an additional 13 patients (not included in the enriched group) known to have a cancer predisposition gene PV. Only two (15%) had findings on LB reports that suggested germline testing would be indicated. Conclusions: While the purpose of somatic testing is to identify targeted therapy, it can provide germline insight, especially for patients not typically referred for genetic assessment. Further education and guidance is needed to assure that this aspect of somatic testing is appreciated by oncology providers and acted upon.[Table: see text]

Concomitant Systemic Therapy: Current and Future Perspectives

Chemotherapy in combination with radical cystectomy or radiotherapy has led to improved oncological outcomes in the definitive treatment of muscle-invasive bladder cancer (MIBC). Here we discuss the current role of chemotherapy and immunotherapy in the management of MIBC and discuss future directions of treatment.

Abstract D104: Presentation, treatment, and survival of hepatocellular carcinoma (HCC) in a diverse population: Experience of a single transplant center

Background: HCC has pathognomonic imaging and predominantly non-surgical treatment paradigms. Most patients do not have histological diagnosis, an integral part of case identification for population based cancer registries. The unique patterns of diagnosis and treatment may hamper population-based study of HCC outcomes and patterns of care. We examined racial differences in the HCC underlying etiology, presentation, treatment, and outcome in a diverse patient population in a single transplant center. Methods: HCC patients who were diagnosed/treated at Norris Comprehensive Cancer Center between 2003-2018 were identified from cancer registry. Registry data including vital status were linked with medical records. Demographics, stage at diagnosis [Barcelona Clinic Liver Cancer stage (BCLC) and Tumor Node Metastasis (TNM)], underlying etiology [hepatitis C (HCV), hepatitis B (HBV), nonalcoholic steatohepatitis (NASH), alcoholic liver disease], treatment information, and vital status were retrieved. The chi-square test was used to compare characteristics of patients by race. Multivariable Cox’s models were used to identify factors associated with overall survival. Results: A total of 619 patients (152 non-Hispanic whites (NHW), 285 Hispanics, 158 Asians, and 24 African Americans) were included in the analysis. The median follow-up was 27.0 months. The average age at diagnosis was 63 years, and 76% of patients were male. Underlying etiology varied significantly across racial groups (P&lt;0.0001); HCV was the most common etiology in African Americans (79%), NHW (70%), and Hispanics (52%), while HBV was the main etiology in Asians (54%). The proportion of NASH-related HCC was 13% in Hispanics, 8% in NHW, 4% in African Americans, and 3% in Asians. There was no significant difference in TNM stage at presentation, however, compared to NHW (36%), Asians (48%) and Hispanics (52%) were more likely to be diagnosed with Barcelona stage A (P≤0.021). Median AFP values at presentation was highest in African Americans and lowest in Hispanics (P heterogeneity ≤0.033). Only 7% of patients received no treatment, 49, 26, and 19% of patients received locoregional, systemic, or transplant respectively. There was no difference in access to these treatments by race, despite significant differences in the insurance status. In the multivariate analyses, higher stage at presentation, NASH-related HCC, and non-transplant treatment were associated with worse survival. Surveillance for HCC showed trend for improved survival (P=0.057). Conclusion: Among patients with appropriate and similar access to care prognosis of HCC is driven by stage, underlying etiology, and curative treatment. Surveillance may improve survival in patients with appropriate access to care.

Citation Format: Afsaneh Barzi, Ravi Patel, Varsha Tulpule, Robert Albertian, Bo Yu, Gwendolyn Lynch, Anthony El-Khoueiry, Songren Wang, Veronica Wendy Setiawan. Presentation, treatment, and survival of hepatocellular carcinoma (HCC) in a diverse population: Experience of a single transplant center [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D104.

Author Correction: PIC&RUN: An integrated assay for the detection and retrieval of single viable circulating tumor cells

An amendment to this paper has been published and can be accessed via a link at the top of the paper.