Potential Biomarker In Renal Cell Carcinoma Research Articles

Immunotherapy Applications for Thymine Dimers and WT1 Antigen in Renal Cancers: A Comparative Statistical Analysis.

Renal cell carcinoma (RCC) remains incurable in advanced stages. Biomarkers have proven to be quite useful in cancer therapeutics. Herein, we provide a comparative/integrative statistical analysis of seminal immunohistochemistry (IHC) findings for Wilms' Tumor 1 antigen (WT1) and thymine dimers (TDs), emerging as atypical, yet promising, potential biomarkers for RCCs. We assessed WT1/TD reactivity in adult RCC tumor cells, tumor microenvironment (TME), and tumor-adjacent healthy renal tissue (HRT). WT1 positivity was scarce and strictly nuclear in tumor cells, whereas TD-reactive tumor tissues were prevalent. We report statistically significant positive correlations between the density of reactive RCC cellularity and the intensity of nuclear staining for both biomarkers (WT1 - rho = 0.341, p-value = 0.036; TDs - rho = 0.379, p-value = 0.002). RCC stromal TME TD-positivity was much more frequent than WT1 reactivity, apparently proportional to that of the proper RCC cellularity and facilitated by extensive RCC inflammatory infiltration. TDs exhibited nuclear reactivity for most TME cell lines, while RCC TME WT1 expression was rare and inconsistent. In HRTs, TDs were entirely restricted to renal tubular cells, the likely cellular progenitor of most conventional RCC subtypes. In lieu of proper validation, these early findings have significant implications regarding the origins/biology of RCCs and may inform RCC therapeutics, both accounting for the high frequency of immunotherapy-permissive frameshift indels in RCCs, but also hinting at novel predictive clinical tools for WT1-targeted immunotherapy. Overall, the current study represents a meek yet hopefully significant step towards understanding the molecular biology and potential therapeutic targets of RCCs.

KIDNEY-PAGER: analysis of circulating tumor DNA as a biomarker in renal cancer - an observational trial. Study protocol.

Management of localized renal cell carcinoma (RCC) is challenged by inaccurate methods to assess the risk of recurrence and deferred detection of relapse and residual disease after radical or partial nephrectomy. Circulating tumor DNA (ctDNA) has been proposed as a potential biomarker in RCC. Conduction of an observational study to evaluate the validity of ctDNA as a biomarker of the risk of recurrence and subclinical residual disease to improve postoperative surveillance. Urine and blood will be prospectively collected before and after surgery of the primary tumor from up to 500 patients until 5 years of follow-up. ctDNA analysis will be performed using shallow whole genome sequencing and cell-free methylated DNA immunoprecipitation sequencing. ctDNA levels in plasma and urine will be correlated to oncological outcomes. Residual blood and urine as well as tissue biopsies will be biobanked for future research. Results will pave the way for future ctDNA-guided clinical trials aiming to improve RCC management.

MiR-224-5p Contained in Urinary Extracellular Vesicles Regulates PD-L1 Expression by Inhibiting Cyclin D1 in Renal Cell Carcinoma Cells.

Simple SummaryThe detailed effects of abundant microRNAs contained in extracellular vesicles (EVs) on renal cell carcinoma (RCC) progression are still unclear. This study identified the overexpression of miR-224-5p in urinary EVs of RCC patients. miR-224-5p suppressed RCC cell proliferation and induced cell cycle arrest through inhibiting cyclin D1 expression. PD-L1 protein abundance was increased by miR-224-5p, and this regulation could be transmitted via EVs intercellularly. These findings may shed light on biomarker discovery for RCC immunotherapy.The abundant miRNAs in urinary extracellular vesicles (EVs) represent ideal reservoirs for biomarker discovery, especially in renal cell carcinoma (RCC). However, the content and biological functions of microRNAs contained in urinary EVs in RCC remain ambiguous. In this study, urinary EVs were isolated and characterized from RCC patients and healthy volunteers. Differentially expressed microRNAs in urinary EVs were screened by small RNA sequencing. The target gene and biological functions of selected microRNAs were investigated through multifaceted methods. Results indicated that miR-224-5p was significantly upregulated in urinary EVs of RCC patients compared to healthy volunteers. The overexpression of miR-224-5p inhibited RCC cell proliferation and induced cell cycle arrest. The gene CCND1 encoding cyclin D1 was identified as a direct target of miR-224-5p via prediction and validation. Moreover, the invasive and metastatic abilities of RCC cells were enhanced by miR-224-5p. Interestingly, miR-224-5p also increased the stability of PD-L1 protein by inhibiting CCND1. This effect could be transmitted via EVs and further promoted the resistance of RCC cells to T cell-dependent toxicity. In summary, urinary EVs containing miR-224-5p were identified as a potential biomarker in RCC. Regulation of PD-L1 protein expression by miR-224-5p through suppressing CCND1 elucidates new roles of miR-224-5p in RCC progression.

Serum long non‐coding RNA LINC00887 as a potential biomarker for diagnosis of renal cell carcinoma

The identification of non‐invasive biomarkers for the detection of renal cell carcinoma (RCC) in early‐stage patients may help improve disease outcome. Certain long non‐coding RNAs (lncRNAs) have been reported to be possible biomarkers for the diagnosis and prognosis of cancer. Here, we examined the suitability of the lncRNA LINC00887 as a potential biomarker for RCC because its expression has been shown to be elevated in RCC tissue versus normal tissue in the Gene Expression Profiling Interactive Analysis (GEPIA) database. We found that LINC00887 expression is significantly increased in early‐stage RCC tissues and the serum of early‐stage RCC patients compared to matched normal tissues and the serum of healthy subjects, respectively. We also demonstrated that elevated serum LINC00887 is generated from the tumor tissues of RCC patients. Moreover, a receiver operating characteristic (ROC) curve was generated to analyze the diagnostic value of serum LINC00887. The area under the ROC cure differentiating early‐stage RCC patients from healthy subjects was 0.8001, with a sensitivity of 71.05% and a specificity of 89.87%. Furthermore, we found that LINC00887 promotes RCC cell proliferation in vitro. Taken together, our findings suggest that a serum LINC00887 signature is associated with RCC cell proliferation and may be a potential biomarker for the detection of early‐stage RCC.

Circulating miR-378 and miR-451 in serum are potential biomarkers for renal cell carcinoma

BackgroundThere is no standard serum biomarker used for diagnosis or early detection of recurrence for renal cell carcinoma (RCC) patients. MicroRNAs (miRNAs) are abundant and highly stable in blood serum, and have been recently described as powerful circulating biomarkers in a wide range of solid cancers. Our aim was to identify miRNA signature that can distinguish the blood serum of RCC patients and matched healthy controls and validate identified miRNAs as potential biomarkers for RCC.MethodsIn the screening phase of the study, blood serum of 15 RCC patients and 12 matched healthy controls were analyzed by use of the TaqMan Low-Density Arrays enabling parallel identification of expression levels of 667 miRNAs through qRT-PCR-based approach. In the validation phase, identified miRNAs were further evaluated on the independent group of 90 RCC patients and 35 matched healthy controls by use of individual qRT-PCR assays and statistically evaluated.ResultsWe identified 30 miRNAs differentially expressed between serum of RCC patients and healthy controls: 19 miRNAs were up-regulated and 11 miRNAs were down-regulated in RCC patients. MiR-378, miR-451 and miR-150 were further evaluated in the independent group of patients, and two of them were successfully validated: levels of miR-378 were increased (p = 0.0003, AUC = 0.71), miR-451 levels were decreased (p < 0.0001, AUC = 0.77) in serum of RCC patients. Combination of miR-378 and miR-451 enable identification of RCC serum with the sensitivity of 81%, specificity 83% and AUC = 0.86.ConclusionsCirculating miRNAs in serum are promising biomarkers in RCC.

Circulating endothelial cells are a potential biomarker for patients with renal cell carcinoma (RCC) with and without von Hippel Lindau (VHL) syndrome

5098 Background: VHL is a primary cause of inherited RCC and 60% of sporadic clear cell RCCs have mutations in the VHL gene. RCCs often remain asymptomatic for long intervals. Diagnosis during presymptomatic screening has the potential to improve overall outcome. Circulating endothelial cells (CECs) are a potential biomarker for monitoring angiogenesis. Mature CECs are thought to be shed from existing vessels while circulating endothelial progenitors (CEPs) are thought to be derived from bone marrow. We sought to assess the potential of CECs and CEPs as markers of RCC in pts with VHL and sporadic RCC. Methods: Batch analysis of PBMCs obtained from consenting pts with sporadic or VHL associated RCC, VHL (without RCC), and normal volunteers (NV) was performed FACS analysis was performed using a panel for four antibodies including CD45, CD31, CD146, and CD133. CECs were defined as CD45-, CD31+ and CD146+, and CD133-. CEPs had the same phenotype but were CD133+. Results: RCC pts have higher CECs, CEPs and CEP/CEC ratio as compared to NV (p<0.05 for each comparison). Additionally, these 3 parameters were similar in NV and pts with VHL without RCC. However pts with VHL and RCC had significantly higher CEP/CEC ratio and CEP values than pts with VHL without RCC. (p<0.05 for each comparison) (Table). Conclusions: CECs are a potential biomarker for RCC in pts with sporadic RCC. These data suggests that CEPs and CEP/CEC ratio may represent a screen that may allow for the early detection of RCC in VHL pts. Larger studies will be needed to validate these findings. Supported by VHL Family Alliance (Joyce Graff Director) the DF/HCC Kidney Cancer SPORE P50CA101942, and the ASCO YIA. Average CEC (cells/ul) Average CEP (cells/ul) Average CEP/CEC RCC (n=10) * 2.36 2.08 1.97 NV (n=17) 0.45 0.21 0.61 VHL (without RCC) (n=13) 0.54 0.19 0.67 VHL (with RCC) (n=6) 3.16 2.91 2.76 * includes pts with VHL and RCC (n=6) and pts with sporadic RCC (n=4). No significant financial relationships to disclose.