Risk Prediction Tool for Aggressive Tumors in Clinical T1 Stage Clear Cell Renal Cell Carcinoma Using Molecular Biomarkers

Abstract

Some early-stage clear cell renal cell carcinomas (ccRCCs) of ≤7 cm are associated with a poor clinical outcome. In this study, we investigated molecular biomarkers associated with aggressive clinical T1 stage ccRCCs of ≤7 cm, which were used to develop a risk prediction tool toward guiding the decision of treatment. Among 1069 nephrectomies performed for ccRCC of ≤7 cm conducted between January 2008 and December 2014, 177 cases with available formalin-fixed paraffin-embedded tissue were evaluated. An aggressive tumor was defined as a tumor exhibiting synchronous metastasis, recurrence, or leading to cancer-specific death. Expression levels of six genes (FOXC2, CLIP4, PBRM1, BAP1, SETD2, and KDM5C) were measured by reverse-transcription polymerase chain reaction (qRT-PCR) and their relation to clinical outcomes was investigated. Immunohistochemistry was performed to validate the expression profiles of selected genes significantly associated with clinical outcomes in multivariate analysis. Using these genes, we developed a prediction model of aggressive ccRCC based on logistic regression and deep-learning methods. FOXC2, PBRM1, and BAP1 expression levels were significantly lower in aggressive ccRCC than non-aggressive ccRCC both in univariate and multivariate analysis. The immunohistochemistry result demonstrated the significant downregulation of FOXC2, PBRM1, and BAP1 expression in aggressive ccRCC. Adding immunohistochemical staining results to qRT-PCR, the aggressive ccRCC prediction models had the area under the curve (AUC) of 0.760 and 0.796 and accuracy of 0.759 and 0.852 using the logistic regression method and deep-learning method, respectively. Use of these biomarkers and the developed prediction model can help stratify patients with clinical T1 stage ccRCC.

Gene Expression Analysis of Aggressive Clinical T1 Stage Clear Cell Renal Cell Carcinoma for Identifying Potential Diagnostic and Prognostic Biomarkers

“…This finding is similar to the results of other studies that have reported an association between BAP1 and KDM5C mutations and aggressiveness of tumors [9,10]. FOXC2, a gene known to be associated with tumor aggressiveness and synchronous metastasis in ccRCC, based on our previous studies [2,11], was found to be associated with aggressive characteristics of tumors in early-stage ccRCC, in the present study. The frequency of PBRM1 mutation was similar between patients with aggressive and non-aggressive ccRCC, perhaps because it is an early, essential event in tumorigenesis that does not impact clinical outcome, but instead plays a principal role in tumor initiation.…”

“…Forkhead box protein C2 (FOXC2) and cytoskeleton-associated protein-glycine (CAP-Gly) rich domain-containing linker protein family member 4 (CLIP4) mutations were associated with early-stage ccRCC and synchronous metastasis [3]. Furthermore, PBRM1, BAP1, and FOXC2 were shown to be significantly associated with aggressive early-stage ccRCC through target sequencing and immunohistochemistry in our previous study [11].…”

Association between visceral adiposity and DDX11 as a predictor of aggressiveness of small clear-cell renal-cell carcinoma: a prospective clinical trial

“…Diameters of the primary tumors were obtained via CT imaging. We assessed the expression levels of six genes (PBRM1, BAP1, SETD2, KDM5C, FOXC2, and CLIP4) reportedly associated with ccRCC, and four genes (AQP1, DDX11, BAIAP2L1, and TMEM38B) examined in our previous study involving RNA-seq analysis of aggressive ccRCC in clinical T1 stage [16,17].…”

“…Previously, we found that several potential prognostic biomarkers are considerably up-or downregulated in ccRCC, and can be used to identify the aggressive clinical T1-stage [16,17]. In this study, we aimed to determine the association between visceral adiposity and the mRNA expression of potential biomarkers using frozen tumor tissues and preoperative plasma of patients with small ccRCC.…”

Integrative Radiogenomics Approach for Risk Assessment of Post-Operative Metastasis in Pathological T1 Renal Cell Carcinoma: A Pilot Retrospective Cohort Study

“…Recently, radiogenomics has been focused on elucidating novel imaging-genomic correlates for predicting clinical outcomes and tailored treatment strategies in RCC showing high inter-and intratumoral genomic and molecular heterogeneity [11][12][13]. Especially, postoperative distant metastases develop in a significant proportion of patients designated as cancer-free after curative surgery for localized RCC, primarily due to occult micrometastasis in 20%-35% of patients [17,18]. Therefore, the development of an accurate system to predict patient metastasis is needed to allow for better patient selection of those most likely to benefit from adjuvant therapy.…”