The Wide Experience of the Sequential Therapy for Patients with Metastatic Renal Cell Carcinoma

Identification and validation of a two-gene metabolic signature for survival prediction in patients with kidney renal clear cell carcinoma

Metabolic reprogramming contributes to the high mortality of advanced stage kidney renal clear cell carcinoma (KIRC), the most common renal cancer subtype. This study aimed to identify a metabolism-related gene (MRG) signature to improve survival prediction in KIRC patients. We downloaded RNA sequencing data and corresponding clinical information for KIRC and control samples from The Cancer Genome Atlas database and identified, based on an MRG dataset in the Molecular Signatures Database, 123 MRGs with differential expression in KIRC. Following Cox regression analysis and least absolute shrinkage and selection operator selection, RRM2 and ALDH6A1 were identified as prognosis-related genes and used to construct a prognostic signature with independent prognostic significance. After risk score-based patient separation, stratified survival analysis indicated that high-risk patients showed poorer overall survival than low-risk patients. We then constructed a clinical nomogram that showed a concordance index of 0.774 and good performance based upon calibration curves. Gene set enrichment analysis revealed several metabolic pathways significantly enriched in the target genes. The two-gene metabolic signature identified herein may represent a highly valuable tool for KIRC prognosis prediction, and might also help identify new metabolism-related biomarkers and therapeutic targets for KIRC.

Metastatic renal cell carcinoma regains sensitivity to tyrosine kinase inhibitor after nivolumab treatment: A case report

Sequential therapy using tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin inhibitors is the mainstay of treatment for metastatic renal cell carcinoma. Recently, anti-programmed death-1 (PD-1) antibody, a type of immune checkpoint inhibitor, was approved for use against metastatic renal cell carcinoma. In the present report, two cases of TKI-refractory metastatic renal cell carcinoma which regained sensitivity to TKI after immunotherapy with nivolumab were described. In one case, a third challenge with axitinib after nivolumab treatment resulted in tumor shrinkage, although the second challenge with axitinib immediately before nivolumab treatment had no effect. In another case, a second challenge with pazopanib after nivolumab slightly reduced lung metastasis, which was refractory to pazopanib before nivolumab treatment. These cases suggest that nivolumab can influence the response to subsequent TKI treatment.

LncRNA UCA1 promotes renal cell carcinoma proliferation through epigenetically repressing p21 expression and negatively regulating miR-495

Long non-coding RNAs have recently emerged as important regulators in the pathogenesis and progression of cancers. The long non-coding RNA urothelial carcinoma–associated 1 is reportedly upregulated and functions as an oncogene in some tumors. However, the role of urothelial carcinoma–associated 1 in renal cell carcinoma is not well elucidated so far. In this study, we found that urothelial carcinoma–associated 1 was overexpressed in renal cell carcinoma tissues compared with the adjacent normal tissues, and higher urothelial carcinoma–associated 1 expression levels were positively associated with advanced tumor stage and poor survival time in renal cell carcinoma patients. Further studies showed that knockdown of urothelial carcinoma–associated 1 suppressed renal cell carcinoma cell proliferation and S-phase cell number in vitro. Moreover, urothelial carcinoma–associated 1 was found to be associated with enhancer of zeste homolog 2, which suppressed p21 expression through histone methylation (H3K27me3) on p21 promoter. We also showed that knockdown of urothelial carcinoma–associated 1 increased the p21 protein expression through regulating enhancer of zeste homolog 2. In addition, bioinformatics analysis and dual-luciferase reporter assays confirmed that miR-495 was a target of urothelial carcinoma–associated 1 in renal cell carcinoma, and urothelial carcinoma–associated 1 promoted cell proliferation by negatively regulating miR-495. These findings illuminated that urothelial carcinoma–associated 1 promoted renal cell carcinoma progression through enhancer of zeste homolog 2 and interacted with miR-495. Overall, overexpression of urothelial carcinoma–associated 1 functions as an oncogene in renal cell carcinoma that may offer a novel therapeutic target for renal cell carcinoma patients.

Stromal expression of Fer suppresses tumor progression in renal cell carcinoma and is a predictor of survival

Fps/Fes related (Fer) is a non-receptor tyrosine kinase that is expressed in fibroblasts, immune cells and endothelial cells. Fer serves an important pathological role in cell survival, angiogenesis and the immune system. However, the pathological role of Fer expression in the stromal cells surrounding renal cell carcinoma (RCC) has not been previously investigated. In the present study, immunohistochemical analysis of Fer was performed using the formalin-fixed tissue samples of 152 patients with RCC. The proliferative and apoptotic indices were used to represent the percentage of proliferation marker protein Ki-67- and cleaved caspase-3-positive cells, respectively. The microvessel density was defined as the number of cluster of differentiation (CD) 31-positively stained vessels/mm². In addition, CD57⁺ and CD68⁺ cells were counted using semi-quantification of natural killer (NK) cells and macrophages. Fer expression in stromal cells was negatively associated with Fuhrman grade, pathological tumor stage and metastasis (P<0.001). Fer expression in stromal cells was negatively associated with CD68⁺ macrophage density, whereas it was positively associated with CD57⁺ NK cell density. Kaplan-Meier estimators indicated that decreased stromal Fer expression was a predictive marker of decreased cause-specific survival rate (P<0.001). Furthermore, low expression of Fer was identified as being an independent marker of decreased cause-specific survival using multivariate analysis (hazard ratio, 7.4; 95% confidence interval, 1.7-33.0; P<0.001). The results of the present study suggested that low Fer expression in stromal cells is associated with increased malignant aggressiveness and decreased survival in patients with RCC. CD57⁺ NK cell and CD68⁺ macrophage regulation in cancer-stromal tissue is considered to affect RCC pathology.