Loss of heterozygosity of key tumor suppressor genes in advanced renal cancer patients treated with nivolumab

Methylation of PCDH17 and NEFH as prognostic biomarker for nonmetastatic RCC: A cohort study

DNA methylation makes up a main part of the molecular mechanism of cancer evolution and has shown promising results in the prognosis of renal cell cancer (RCC). In this study, we investigated the possible association of promoter methylation of PCDH17, NEFH, RASSF1A, and FHIT, genes with the prognosis of nonmetastatic RCC patients. Cancerous and normal adjacent tissues from surgical specimens of 41 patients with long follow-up were treated for DNA isolation and bisulfite conversion. The gene promoter methylation was determined with quantitative methylation-specific PCR (qMSP). Wilcoxon signed-rank test was used for paired methylation comparisons, while univariate linear regression and Mann-Whitney test were applied for associating methylation status with clinical and disease characteristics. Cox regression proportional hazards models and Kaplan-Meier plots were used for survival analyses in reference to methylation status. Paired comparisons showed tissue-specific hypermethylation for PCDH17 (P < .001), NEFH (P < .001), RASSF1A (P = .032), while a positive association of methylation in normal tissues with age was demonstrated for PCDH17 (P < .001), RASSF1A (P < .001), FHIT (P < .001). PCDH17 was more methylated in cases with clear cell RCC (P = .015) and high-grade tumor (P = .013), while NEFH methylation was higher in locally advanced cases (P = .032). PCDH17 hypermethylation in cancerous and normal tissues was linked to shorter disease-specific survival (DSS, P = .026, P = .004), disease-free survival (DFS, P = .004, P = .019) while NEFH hypermethylation in cancerous tissues was related to shorter DSS (P = .032). Increased methylation difference of NEFH was also associated with shorter DSS (P = .041) and DFS (P = .020), while the corresponding parameter for PCDH17 was associated with poor DFS (P = .014). Kaplan-Meier curves for hypermethylation in cancer tissues demonstrated different clinical courses for PCDH17 (P = .017), NEFH (P = .023) regarding DSS, and PCDH17 (P = .001) regarding DFS. Our study not only highlights the prognostic value of promoter methylation of PCDH17 and NEFH in cancer tissues but also is the first report of the prognostic value of methylation alterations in normal tissues. Our findings are the first report of the prognostic value of methylation alterations in normal tissues, which can contribute to improved assessment of recurrence risk.

Prognostic and predictive molecular biomarkers in metastatic renal cell carcinoma patients treated with immune checkpoint inhibitors: a systematic review

Introduction: In recent years, the treatment landscape of metastatic renal cell carcinoma (mRCC) has been improved using immune-checkpoint inhibitors (ICI). Nevertheless, the number of patients experiencing clinical benefit from immunotherapy is still limited, while others obtain more benefit from tyrosine kinase inhibitors (TKI). The identification of prognostic and predictive factors would be crucial to better select patients most likely to benefit from immunotherapy among the other potentially available therapeutic options.Areas covered: This systematic review summarizes the current knowledge (2010-2019) on molecular prognostic and predictive biomarkers, assessed in peripheral blood and/or from tumor tissue, in mRCC patients treated with ICI.Expert opinion: Among all the biomarkers analyzed, PD-L1 expression on tumor tissue is the most studied. It has an unfavorable prognostic role for patients treated with TKI, which seems to be overcome by ICI-based combinations. Nevertheless, no clear predictive role of immunotherapy efficacy has been observed for PD-L1 in mRCC. Emerging evidence regarding pro-angiogenic or pro-immunogenic genomic and transcriptomic signatures suggests a potential predictive role in patients treated with ICI-based combinations. The rationale for TKI-ICI combinations is based on tumor microenvironment and genomic background, which represent the target of these two main therapeutic options for mRCC.