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.

Measuring ß-Galactosidase Activity in Gram-Positive Bacteria Using a Whole-Cell Assay with MUG as a Fluorescent Reporter.

The use of ß-galactosidase enzyme as a biomarker has the potential to determine activity levels of the microbiome of a variety of organisms due to its common presence in both eukaryotes and prokaryotes. Completing the assay in a whole-cell format facilitates the monitoring of ß-galactosidase activity in its actual cellular environment. This unit describes an optimized fluorescent assay for ß-galactosidase that has enough sensitivity to detect the enzymatic activity despite the thick gram-positive bacterial cellular membrane. The use of a smaller fluorometric substrate, namely 4-methylumbelliferyl ß-D-galactopyranoside (MUG), has facilitated its penetration into the cells as well as its direct detection without any extra steps. This assay provides an improved technique for measuring a well-studied reporter enzyme and offers new avenues for using ß-galactosidase as a biomarker. © 2017 by John Wiley & Sons, Inc.

Fluorometric cell-based assay for ß-galactosidase activity in probiotic gram-positive bacterial cells - Lactobacillus helveticus.

Although methods for measuring ß-galactosidase activity in intact gram-negative bacterial cells have been reported, the methods may not be applicable to measuring ß-galactosidase activity in gram-positive bacterial cells. This report focuses on the development of a fluorometric cell-based assay for measuring ß-galactosidase activity in gram-positive cells.

Single nucleotide polymorphisms in type 2 diabetes among Hispanic adults.

In this pilot study, we explore the genetic variation that may relate to type 2 diabetes (T2D) among Hispanic adults. The genotypes of 36 Hispanic adults were analyzed by using the Cardio-Metabochip. The goal is to identify single nucleotide polymorphisms (SNPs) associated to T2D among Hispanic adults. A total of 26 SNPs were identified to be associated with T2D among Hispanic adults. None of these SNPs have been reported for T2D. By using the principle components analysis to analyze the genotype of 26 SNPs in 36 samples, the samples obtained from diabetic patients could be distinguished from the control samples. The findings support genetic involvement in T2D among Hispanic adults.