Methylation-associated silencing of microRNA-34b in hepatocellular carcinoma cancer.
MicroRNAs (miRNAs) can act as oncogenes or tumor-suppressor genes in human cancers including HCC. Previous studies have identified miR-34 family as an important component of the tumor suppressor network during carcinogenesis. In this study, we investigated the methylation status of miR-34 family in HCC tumor and adjacent non-tumor tissues using methylation-specific PCR (MSP). The methylation frequencies of miR-34a and miR-34b/c were 72.1% (31/43) and 79.1% (34/43) in HCC tissues, which were significantly higher than that in the adjacent non-tumor tissues (P < 0.05), respectively. The results were validated by bisulfite sequencing PCR (BSP). Quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis showed that the expression of miR-34a and miR-34b was significantly down-regulated in HCC tissues compared with adjacent non-tumor tissues (P < 0.05). Moreover, the expression of miR-34b was inversely correlated to CpG island methylation in tumor tissues, but not for miR-34a. In summary, our results suggest that DNA methylation may be involved in the inactivation of miR-34b in HCC.
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
Kaipeng
K
Xie
Tumor Institute, Nantong Tumor Hospital, Nantong 226361, Jiangsu Province, China. Electronic address: tians2008@163.com.cn.
Jibin
J
Liu
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
Jiaping
J
Chen
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
Jing
J
Dong
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
Hongxia
H
Ma
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
Yao
Y
Liu
Department of Epidemiology and Biostatistics, Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China; State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China. Electronic address: zhibin_hu@njmu.edu.cn.
Zhibin
Z
Hu
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation / Q000502:physiology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics*; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged
C522425:MIRN34 microRNA, human; D035683:MicroRNAs
Hepatocellular carcinoma; Methylation; miR-34a; miR-34b/c