[Correlation of methylation of CpG island in cystathionine beta synthase promoter and clinicopathological features in colorectal cancer].
OBJECTIVE
To explore the association between methylation of cystathionine-beta-synthase (CBS) promoter and clinicopathological features in colorectal cancer.


METHODS
Bisulfate sequencing PCR, real-time RT-PCR, and immunohistochemistry were used to investigate the methylation of CpG island in CBS promoter of 95 sporadic colorectal cancers. Software SPSS PASW Statistics was used to analyze the data of the hypermethylation levels in the malignant tissues and the correlation with pathological parameters and clinical outcome.


RESULTS
Methylation levels in tumor tissue of patients [(64.9 ± 14.3)%]with colorectal cancer were significantly higher than that in normal tissues[(27.5 ± 13.1)%, P < 0.001]. The CBS mRNA levels in the hypomethylation group (7.22 ± 1.91) were significantly higher than that in the hypermethylation group (2.78 ± 1.12, P < 0.01). Univariate analysis showed that age, pT stage, pN stage, liver metastases, pTNM stage, and CBS hypermethylation level significantly correlated with the survival and recurrence rates of colorectal cancer patients (All P < 0.05). Multivariate analysis showed that CBS hypermethylation level and liver metastasis were independent factors significantly correlated with the recurrence rate and overall survival of the patients (All P < 0.05).


CONCLUSIONS
Our study indicates that methylation of CpG island in CBS promoter is correlated with the occurrence and progression of colorectal cancer and plays a role in its tumorigenesis. It might serve as a useful marker for early diagnosis, targeted therapy and prediction of prognosis in colorectal cancer.
Department of General Surgery, Fuzong Medical College, Fujian Medical University (Fuzhou General Hospital of Nanjing Military Command), Fuzhou 350025, China.
Xiao-huang
XH
Tu
Shao-xiong
SX
Huang
Wen-sheng
WS
Li
Jing-xiang
JX
Song
D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018899:CpG Islands / Q000235:genetics; D003541:Cystathionine beta-Synthase / Q000235:genetics* / Q000378:metabolism; D019175:DNA Methylation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism
D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D003541:Cystathionine beta-Synthase