RNA sequencing in a penile cancer cohort: an investigation of biomarkers of cisplatin resistance and potential therapeutic drug targets.

OBJECTIVE: Chemoresistance in distant micrometastatic lesions may account for diminished durable response rates in advanced penile cancer. However, there are limited studies on new therapeutic targets and the identification of biomarkers that predict chemotherapy response in this population. Thus, we examine the expression of candidate biomarkers of cisplatin resistance, ERCC1 and E2F1, and perform next-generation sequencing on the cancer transcriptome in a penile cancer cohort. MATERIALS AND METHODS: In this retrospective cohort study, we identified 71 patients treated for penile squamous cell carcinoma between 2009 and 2019. Immunohistochemistry staining for ERCC1 and E2F1 was performed. H-scores were measured for patient specimens obtained from adjacent normal skin, primary tumor and metastatic lymph node specimens and correlated with RNA expression data obtained through next-generation sequencing. RESULTS: Of the 71 patients identified, 51 and 8 had available surgical specimens for immunohistochemistry and RNA sequencing, respectively. Median H-scores for ERCC1 in adjacent normal skin, primary and metastatic tumors were 17.04, 3.15, and 7.9 respectively compared to E2F1 (43.95, 15.54, 7.9). The median H-score for E2F1 was higher in poorly differentiated primary tumors (24.86) compared to well (7.62) and moderately differentiated (9.55, p = 0.055). Next generation sequencing showed no difference in RNA expression of E2F1 nor ERCC1 between primary tumors and metastatic lesions however did demonstrate elevated RNA expression of genes such as MMP1, and MMP10 in primary tumors compared to adjacent normal skin. CONCLUSION: We identify potential drug targets for metastatic penile cancer through next-generation RNA sequencing.

Nuclear NADPH oxidase-4 associated with disease progression in renal cell carcinoma.

Nuclear NADPH oxidase-4 (Nox4) is a key component of metabolic reprogramming and is often overexpressed in renal cell carcinoma (RCC). However, its prognostic role in RCC remains unclear. Here we examined the significance of nuclear Nox4 on disease progression and development of drug resistance in advanced RCC. We analyzed human RCC tissue from multiple regions in the primary index tumor, cancer-associated normal adjacent parenchyma, intravascular tumor in locally advanced cancer patients. We found that the higher nuclear Nox4 expression was significantly associated with progression and death. These findings were consistent after controlling for other competing clinical variables. In contrast, patients with lower nuclear Nox4, even in higher stage RCC had better prognosis. We identified a subset of patients with high nuclear Nox4 who had rapid disease progression or died within 6 months of surgery. In addition, higher nuclear Nox4 level correlated with resistance to targeted therapy and immunotherapy. Western blotting performed on fresh human RCC tissue as well as cell-lines revealed increased nuclear Nox4 expression. Our data support an important prognostic role of Nox4 mediated regulation of RCC independent of other competing variables. Nox4 localizes to the nucleus in high-grade, high-stage RCC. Higher nuclear Nox4 has prognostic significance for disease progression, poor survival, and development of drug resistance in RCC.