The association between the triglyceride-glucose index and prognosis in postoperative renal cell carcinoma patients: a retrospective cohort study.

Background: Insulin resistance has been proven to be associated with renal cell carcinoma (RCC). However, the prognostic value of the triglyceride-glucose (TyG) index, as a marker for insulin resistance (IR), is still unclear. Therefore, we conducted research to explore the prognostic value and the predictive performance of the TyG index in postoperative RCC patients. Methods: A total of 651 postoperative RCC patients from January 2016 to June 2018 were enrolled in the final study. Their clinical and laboratory parameters were collected from medical records and through follow-up by phone. The triglyceride-glucose (TyG) index was calculated as follows: TyG = Ln[TG (mg/dl) × FBG (mg/dL)/2]. The overall survival (OS) and disease-free survival (DFS) were identified as the main outcomes. Results: The TyG index is an independent prognostic factor for OS (HR = 2.340, 95% CI = 1.506 to 3.64, P < 0.001) and DFS (HR = 2.027, 95% CI = 1.347 to 3.051, P < 0.001) in postoperative RCC patients. Kaplan-Meier survival curves of the different TyG index levels showed statistically significant differences in terms of OS and DFS (log-rank test, P < 0.0001). Furthermore, the TyG index was significantly associated with RCC risk factors. Conclusion: The TyG index is significantly associated with RCC survival. The mechanisms responsible for these results may contribute toward the improvement of RCC prognosis and immunotherapy efficacy and the development of new immunotherapeutic targets.

Identification of tryptophan metabolism- and immune-related genes signature and prediction of immune infiltration landscape in bladder urothelial carcinoma.

Introduction: Tryptophan metabolism is indirectly involved in immune tolerance and promotes response to anticancer drugs. However, the mechanisms underlying tryptophan metabolism and immune landscape in bladder urothelial carcinoma (BLCA) are not fully understood. Methods: A BLCA dataset containing 406 tumor samples with clinical survival information and 19 normal samples were obtained from the Cancer Genome Atlas database. The validation set, GSE32894, contained 223 BLCA tumor samples with survival information, and the single-cell dataset, GSE135337, included seven BLCA tumor samples; both were obtained from the gene expression omnibus database. Univariate and multivariate Cox regression analyses were conducted to evaluate clinical parameters and risk scores. Immune infiltration and checkpoint analyses were performed to explore the immune landscape of BLCA. Single-cell analysis was conducted to further identify the roles of model genes in BLCA. Finally, NAMPT expression in BLCA and adjacent tissues was detected using RT-qPCR, CCK-8 and Transwell assays were conducted to determine the role of NAMPT in BLCA cells. Results: Six crossover genes (TDO2, ACAT1, IDO1, KMO, KYNU, and NAMPT) were identified by overlap analysis of tryptophan metabolism-related genes, immune-related genes, and differentially expressed genes (DEGs). Three biomarkers, NAMPT, IDO1, and ACAT1, were identified using Cox regression analysis. Accordingly, a tryptophan metabolism- and immune-related gene risk model was constructed, and the patients were divided into high- and low-risk groups. There were significant differences in the clinical parameters, prognosis, immune infiltration, and immunotherapy response between the risk groups. RT-qPCR revealed that NAMPT was upregulated in BLCA samples. Knocking down NAMPT significantly inhibited BLCA cell proliferation, migration, and invasion. Discussion: In our study, we constructed a tryptophan metabolism- and immune-related gene risk model based on three biomarkers, namely NAMPT, IDO1, and ACAT1, that were significantly associated with the progression and immune landscape of BLCA. The risk model could effectively predict patient prognosis and immunotherapy response and can guide individualized immunotherapy.

Identifying prognostic characteristics of m6A-related glycolysis gene and predicting the immune infiltration landscape in bladder cancer.

BACKGROUNDS: Glucose metabolism is associated with the development of cancers, and m6A RNA methylation regulator-related genes play vital roles in bladder urothelial carcinoma (BLCA). However, the role of m6A-related glucose metabolism genes in BLCA occurrence and development has not yet been reported. Our study aims to integrate m6A- and glycolysis-related genes and find potential gene targets for clinical diagnosis and prognosis of BLCA patients. METHODS: Sequencing data and clinical information on BLCA were extracted from common databases. Univariate Cox analysis was used to screen prognosis-related m6A glucose metabolism genes; BLCA subtypes were distinguished using consensus clustering analysis. Subsequently, genes associated with BLCA occurrence and development were identified using the "limma" R package. The risk score was then calculated, and a nomogram was constructed to predict survival rate of BLCA patients. Functional and immune microenvironment analyses were performed to explore potential functions and mechanisms of the different risk groups. RESULTS: Based on 70 prognosis-related m6A glucose metabolism genes, BLCA was classified into two subtypes, and 34 genes associated with its occurrence and development were identified. Enrichment analysis revealed an association of genes in high-risk groups with tricarboxylic acid cycle function and glycolysis. Moreover, significantly higher levels of seven immune checkpoints, 14 immune checkpoint inhibitors, and 32 immune factors were found in high-risk score groups. CONCLUSIONS: This study identified two biomarkers associated with BLCA prognosis; these findings may deepen our understanding of the role of m6A-related glucose metabolism genes in BLCA development. We constructed a m6A-related glucose metabolism- and immune-related gene risk model, which could effectively predict patient prognosis and immunotherapy response and guide individualized immunotherapy.

FTO promotes proliferation and migration of bladder cancer via enhancing stability of STAT3 mRNA in an m6A-dependent manner.

N6-Methyladenosine (m6A) plays a key role in the occurrence and development of various cancers. Fat mass and obesity-associated protein (FTO) was is involved in multiple cancers owing to its demethylase activity, and the molecular mechanism underlying FTO-promoted bladder cancer proliferation and migration via the regulation of RNA stability requires further investigation. In the present study, FTO was upregulated in bladder cancer and related to poor prognosis. Gain- and loss-of-function experiments showed that the upregulation of FTO promoted bladder cancer proliferation and migration. Mechanistic studies showed that FTO enhanced the stability of signal transducer and activator of transcription 3 (STAT3) mRNA in an m6A-dependent manner, thereby increasing STAT3 expression, which subsequently promoted P-STAT3 expression and activated STAT3 signalling pathway. Overall, this study revealed that the critical role of FTO in the progression of bladder cancer and could provide a novel avenue to regulate oncogene STAT3.

Comprehensive analysis of N6-methyladenosine regulators with the tumor immune landscape and correlation between the insulin-like growth factor 2 mRNA-binding protein 3 and programmed death ligand 1 in bladder cancer.

BACKGROUND: N6-methyladenosine (m6A) is one of the most abundant post-transcriptional modifications of RNA. However, there is limited information about the potential roles of m6A regulators in tumor immunity. Therefore, in this study, we aimed to testify the functions of m6A regulators in bladder cancer as well as their association with the tumor immune landscape. METHODS: We reported the variation and expression levels of m6A regulators in the TCGA database and GTEx database of bladder cancer. Clusters, risk score patterns, and nomograms were constructed to evaluate the function and prognostic value of m6A regulators. Furthermore, we constructed nomogram to evaluate the prognosis of the individual patients. The correlation between insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) and programmed cell death ligand 1 (PD-L1) was evaluated both in vitro and in vivo. RESULTS: We found that the tumor grade and DNA damage pathways were strongly correlated with distinct clusters. Furthermore, two risk score groups with six m6A regulators were identified using the least absolute shrinkage and selection operator (LASSO) and multivariable Cox regression analysis, which could be regarded as independent prognostic markers in patients with bladder cancer. The risk score pattern was linked to the tumor immune landscape, indicating a correlation between immune checkpoints and m6A regulators. Moreover, an m6A regulator, IGF2BP3, was found to be highly expressed in the tumor samples, regulating both the total and membrane-bound PD-L1 expression levels. CONCLUSIONS: The results of this study revealed that the m6A clusters and patterns play crucial roles in the regulation of tumor immunity, which may be used to develop comprehensive treatment strategies for the management of bladder cancer.

miR-148a-3p inhibits the proliferation and migration of bladder cancer via regulating the expression of ROCK-1.

PURPOSE: To investigate the mechanism of miR-148a-3p regulating the proliferation and migration of bladder tumor cells. MATERIALS AND METHODS: We conducted a preliminary study to detect the relative expression of miR-148a-3p in bladder cancer and para-cancerous tissue samples. Three bladder tumor cell lines, T24, 5,637 and UM-UC-3, were selected. The expression levels of miR-148a-3p were artificially regulated with miR-148a-3p mimics and the miR-148a-3p inhibitor. The relative expression levels of miR-148a-3p in the samples of each cell line were determined. Cell Counting Kit-8 (CCK-8) was used to detect cell proliferation, while the effect of the miR-148a-3p mimics and inhibitor on tumor cell migration was detected by wound healing assay. Flow cytometry assay was carried out to explore the effect of miR-148a-3p on cell apoptosis. Dual-luciferase reporter assay was performed in order to verify miR-148a-3p's target gene. The expressions of ROCK-1 and Bcl-2 were analyzed by western blot. RESULTS: The relative expression of miR-148a-3p in tumor and adjacent tissues was assessed with qRT-PCR (P < 0.05) and found to be significantly lower in the tumor tissues than the adjacent tissues. The data obtained from the CCK-8 and wound healing assay showed that intracellular transfection of miR-148a-3p mimics could inhibit cell proliferation and migration, while the miR-148a-3p inhibitor promoted them. Overexpression of miR-148a-3p promoted cell apoptosis in the T24 and 5,637 cell lines. The dual-luciferase reporter assay verified that ROCK-1 is a direct target of miR-148a-3p. Western blot showed that miR-148a-3p overexpression downregulated the expression of ROCK-1 and Bcl-2, while miR-148a-3p knockdown upregulated the expression of ROCK-1 and Bcl-2. CONCLUSIONS: We confirmed that miR-148a-3p was significantly decreased in bladder cancer cells. miR-148a-3p overexpression inhibited bladder cancer cell proliferation and migration, whereas miR-148a-3p knockdown promoted bladder cancer cell proliferation and migration. Moreover, we found that ROCK-1 was a downstream target of miR-148a-3p. We also found that miR-148a-3p induced cell apoptosis by regulating the expression of Bcl-2. However, the deeper mechanism of this regulatory relationship needs further study.

Circ_0002623 promotes bladder cancer progression by regulating the miR-1276/SMAD2 axis.

Circular RNAs (circRNAs) are key regulatory factors in the development of multiple cancers. This study is targeted at exploring the effect of circ_0002623 on bladder cancer (BCa) progression and its mechanism. Circ_0002623 was screened out by analyzing the expression profile of circRNAs in BCa tissues. Circ_0002623, miR-1276, and SMAD2 mRNA expression levels in clinical sample tissues and cell lines were detected through quantitative real-time polymerase chain reaction (qRT-PCR). After circ_0002623 had been overexpressed or silenced in BCa cells, the cell proliferation, migration, and cell cycle were evaluated by CCK-8, BrdU, Transwell assay, and flow cytometry. Tumor xenograft model was used to validate the biological function of circ_0002623 in vivo. Bioinformatics analysis and dual-luciferase reporter gene assay were conducted for analyzing and confirming, respectively, the targeted relationship between circ_0002623 and miR-1276, as well as between miR-1276 and SMAD2. The regulatory effects of circ_0002623 and miR-1276 on the expression levels of TGF-ß, WNT1, and SMAD2 in BCa cells were detected by Western blot. We reported that, in BCa tissues and cell lines, circ_0002623 was upregulated, whereas miR-1276 was downregulated. Circ_0002623 positively regulated BCa cell proliferation, migration, and cell cycle progression. Additionally, circ_0002623 could competitively bind with miR-1276 to increase the expression of SMAD2, the target gene of miR-1276. Furthermore, circ_0002623 could regulate the expression of TGF-ß and WNT1 via modulating miR-1276 and SMAD2. This study helps to better understand the molecular mechanism underlying BCa progression.

FTO promotes tumour proliferation in bladder cancer via the FTO/miR-576/CDK6 axis in an m6A-dependent manner.

The aberrant expression of fat mass and obesity-associated protein (FTO) has been confirmed to be associated with a variety of cancers and participates in the regulation of multiple biological behaviours. FTO plays an oncogenic role in bladder cancer, but few studies have focused on how FTO promotes bladder cancer progression by regulating miRNA synthesis. Here, we confirmed that FTO expression was significantly increased in bladder cancer and was associated with a poor prognosis. FTO overexpression promoted bladder cancer cell proliferation, whereas FTO knockdown inhibited bladder cancer cell proliferation. We also demonstrated that FTO promoted bladder cancer cell proliferation via the FTO/miR-576/CDK6 pathways. Taken together, our work revealed that FTO plays a critical role in bladder cancer and could be a potential diagnostic or prognostic biomarker for this disease.

Correlation between preoperatively predicted and postoperatively observed renal function using an imaging-based approach: A retrospective cohort study.

The aim of the present study was to preoperatively predict renal function following partial nephrectomy (PN) using an imaging-based approach and to examine the correlation between preoperatively predicted and postoperatively observed renal function in the study cohort. A total of 128 consecutive patients who underwent PN between May 2015 and March 2018 and had available clinical data were included in this study. A hand-scripting method was used to estimate the defected volume (Vdef) from preoperative computerized tomography scans, whereas a cylindrical method was used to obtain preoperative renal volume (Vpre). The function index (FI) was proposed as a new term to estimate preserved parenchyma percentage following PN. The FI was defined as f=(Vpre-Vdef)/Vpre for the operated kidney and adjusted as FI=0.5 × (f + 1) for the bilateral kidneys. The estimated glomerular filtration rates (GFRs) before surgery, one day after surgery and ~12 months after surgery were calculated using the Modification of Diet in Renal Disease Study equation. The GFR rate after PN was predicted by multiplying the preoperative GFR by the FI. The predictive role of the FI was further tested using multiple linear regression and correlation analyses. The median FI in the present study was 94% for unilateral kidney surgery and adjusted to 97% for bilateral kidneys. Linear correlation analysis revealed that the predicted GFR significantly correlated with the observed immediate postoperative GFR (R2, 0.594) and observed late postoperative GFR (R2, 0.828). In multivariate regression analysis, preoperative GFR (P<0.01) and warm ischemic time (P<0.01) were identified as independent determinants of the immediate postoperative renal function, whereas only FI (P<0.01) and preoperative GFR (P<0.01) were identified as independent determinants of late renal function after PN. The preoperatively predicted renal function using an imaging-based approach had a significant positive correlation with the postoperatively observed renal function. The FI estimated from the preoperative diagnostic images in the present study was identified as an independent determinant of long-term renal function after PN.