Expression of p21(WAF1) is related to acetylation of histone H3 in total chromatin in human colorectal cancer.
OBJECTIVE
To explore the relationship between acetylation of histone in total chromatin and p21(WAF1) expression regulation in human colorectal carcinoma.


METHODS
We analyzed the expression of tumor suppressor gene p21(WAF1) mRNA by RT-PCR or real-time PCR in 33 samples of colorectal cancerous tissue, corresponding para-cancerous tissue and normal colorectal mucosa, and also examined the level of acetylated histone H3 in total chromatin using Western blotting.


RESULTS
The expression level of p21(WAF1) mRNA was significantly lower in colorectal cancerous tissue from 33 patients than in para-cancerous tissue and normal colorectal mucosa (2377.95 +/- 865.80 vs 3216.58 +/- 1149.42 and 3541.61 +/- 1433.17 respectively, P < 0.01). In addition, when p21(WAF1) mRNA expression was undectectable or at very low level (50% less than that in adjacent tissue and normal colorectal mucosa) in all tissues, the level of acetylated histone H3 in colorectal cancerous tissue was significantly lower than that in corresponding para-cancerous tissue and normal colorectal mucosa in five of seven (71.43%) cases. The transcriptional level of p21(WAF1) in colorectal carcinoma might not be associated with its biological behaviors.


CONCLUSIONS
The down-regulation of p21(WAF1) transcription is involved in the tumorigenesis and development of colorectal carcinoma. The down-expression of p21(WAF1) mRNA in colorectal carcinoma might be associated with histone hypoacetylation in chromatin but not with biological behaviors.
Chen
Ying-Xuan
YX
Shanghai Jiaotong University School of Medicine Renji Hospital, Shanghai Institute of Digestive Disease, 145 Shandong Zhong Lu, Shanghai 200001, China.
Fang
Jing-Yuan
JY
Lu
Rong
R
Qiu
De-Kai
DK
D000107:Acetylation; D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002843:Chromatin / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism*; D004273:DNA, Neoplasm; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D051548:Histone Acetyltransferases / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011230:Precancerous Conditions / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
C493956:CDKN1A protein, human; D002843:Chromatin; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004273:DNA, Neoplasm; D006657:Histones; D012333:RNA, Messenger; D051548:Histone Acetyltransferases