Abnormal methylation status of FBXW10 and SMPD3, and associations with clinical characteristics in clear cell renal cell carcinoma

Abstract

Abstract. The present study aimed to evaluate the use of the 27K methylation array to investigate abnormal methylation of two genes and their associations with clinical characteristics in clear cell renal cell carcinoma (ccRCC). Six differentially-methylated genes identified using the 27K methylation array were screened in the human RCC 786-0 cell line and normal kidney tissues by bisulfite sequencing polymerase chain reaction (PCR). Differentially-methylated regions (DMRs) that were abnormally hypermethylated in the cell line were further validated in renal tumor and paired normal tissues by pyrosequencing. The correlations between DMRs and differences (methylation rate of tumor minus that of paired normal tissue) according to gender, age, tumor size, Fuhrman grade and disease stage were assessed. Gene expression prior to and following 5-Aza-2'-deoxycytidine treatment was examined using reverse transcription quantitative PCR (RT-qPCR). Two DMRs located in the FBXW10 and SMPD3 genes were found to be hypermethylated in the 786-0 cells, but not in the normal kidney tissues. Pyrosequencing results showed that the average methylation rate of FBXW10 in the cancer tissues was significantly higher compared to that in the paired normal tissues (48.78 vs. 34.62%; P<0.001). The methylation rate of SMPD3 was also higher in the cancer tissues compared with the paired normal tissues (58.98 vs. 38.66%; P<0.001). In stage T1 RCC, the methylation rate of the tumor tissue was positively correlated with the Fuhrman grade (P=0.02). The difference in methylation between the tumor and normal tissues was significantly higher in the group with high Fuhrman grade for the two genes. Furthermore, the linear correlation between methylation difference and tumor size was also confirmed (P=0.01). The RT-qPCR analysis demonstrated that SMPD3 and FBXW10 mRNA expression was significantly upregulated following 5-Aza-2'-deoxycytidine treatment. The results identified two novel DMRs located in SMPD3 and FBXW10 that were hypermethylated in the ccRCC tissue samples. The methylation profile in ccRCC could potentially provide predictive information for clinical decisions.

Identification of Potential Key Genes Associated With the Pathogenesis and Prognosis of Gastric Cancer Based on Integrated Bioinformatics Analysis

“…The prognostic value of SMPD3 and PLEKHS1 in GC has not been validated in previous studies. SMPD3 encodes neutral sphingomyelinase-2 (nSMase2), a sphingomyelinase that catalyzes the hydrolysis of sphingomyelin in biological membranes to ceramide and phosphorylcholine ( Wang et al, 2015 ). SMPD3 as a potential tumor suppressor gene has gained widely studies, and it is linked to numerous malignancies like leukemia, breast cancer, and liver cancer ( Bhati et al, 2008 ; Kim et al, 2008 ; Singh et al, 2014 ; Zhong et al, 2018 ).…”

“…SMPD3 as a potential tumor suppressor gene has gained widely studies, and it is linked to numerous malignancies like leukemia, breast cancer, and liver cancer ( Bhati et al, 2008 ; Kim et al, 2008 ; Singh et al, 2014 ; Zhong et al, 2018 ). Also, abnormal promoter methylation of SMPD3 has been reported in breast cancer, colorectal cancer, clear cell renal cell carcinoma, and hepatocellular carcinoma cells ( Demircan et al, 2009 ; Shen et al, 2012 ; Revill et al, 2013 ; Wang et al, 2015 ). PLEKHS1 remains a largely uncharacterized gene ( Weinhold et al, 2014 ; Kotoh et al, 2016 ).…”

Combined Treatment with Valproic Acid and 5-Aza-2’-Deoxycytidine Synergistically Inhibits Human Clear Cell Renal Cell Carcinoma Growth and Migration

“…5-Aza is a DNMT inhibitor which is currently approved by the FDA for treatment of myelodysplastic syndromes. In RCC models, 5-Aza increased the expression of tumor suppressor genes like FBXW10, SMPD3, and Kank1 and thus suppress tumor cells growth and induce apoptosis [ 31 , 32 ]. 5-Aza treatment also can increase miR-200c, miR-492, and other miRNAs that have a suppressive role in epithelial-mesenchymal transition (EMT) and inhibit migration, invasion, and EMT in ccRCC cells [ 33 , 34 ].…”

Belinostat exerts antitumor cytotoxicity through the ubiquitin‐proteasome pathway in lung squamous cell carcinoma

“…The role of F‐box proteins has been implicated as an important component in tumor progression and development due to their direct regulation on various oncogenic signaling, and pertinently, they have been demonstrated to be epigenetically regulated. For instance, FBXW10 gene is found to be hypermethylated in clear cell renal cell carcinoma (Wang et al ., ), while FBXO3 influences TGF‐β signaling by targeting SMURF1 for proteasomal degradation (Li et al ., ). This epigenetic regulation of the ubiquitin‐proteasome pathway relevant to oncogenesis affords therapeutic opportunity by HDAC inhibition and possibly DNA methylation inhibitors, and our work in lung SCC cells demonstrates this.…”