Significance of mRNA and protein expression of MAC30 in progression of colorectal cancer.
BACKGROUND
Meningioma-associated protein (MAC30), first described to be overexpressed in meningiomas, exhibits altered expression in certain human tumors. The aim of our study was to investigate the expression of MAC30 mRNA and its correlation with clinicopathological variables in human colorectal cancer (CRC).


METHODS
MAC30 mRNA expression was first examined in 55 CRCs, along with the samples from the matched distant normal and adjacent noncancerous tissue by RT-PCR, further verified in 18 CRCs by quantitative RT-PCR. MAC30 protein expression was detected by Western blot in 10 CRCs, and DNA sequencing was performed in 1 case of the paired CRC and the matched noncancerous specimen. MAC30 mRNA expression in two colon cancer cell lines, HCT-116(p53-/-) and HCT-116(p53+/+), was detected by quantitative RT-PCR.


RESULTS
The mRNA expression of MAC30 was increased in CRC when compared with distant normal (p < 0.01) and adjacent noncancerous mucosa (p < 0.01). The mean value of MAC30 mRNA expression in the tumor located in the colon was higher than in the rectum (0.677 ± 0.419 vs. 0.412 ± 0.162, p = 0.005). As the tumor penetrated the wall of the colon/rectum, MAC30 mRNA expression notably increased in tumors with T3+T4 stage compared to tumors with T1+T2 stage (0.571 ± 0.364 vs. 0.404 ± 0.115, p = 0.014). MAC30 protein expression in CRCs was also remarkably elevated compared to the adjacent noncancerous mucosa. There was no mutation in the coding region of the MAC30 gene either in CRC or in the noncancerous mucosa. mRNA expression of p53 was notably decreased in HCT-116(p53-/-) compared to HCT-116(p53+/+), while MAC30 did not vary greatly.


CONCLUSIONS
The overexpression of MAC30 might be involved in the development and aggressiveness of CRCs, especially in the colon.
Department of Surgical Oncology, Tangshan Gongren Hospital, Hebei Medical University, Shijiazhuang, China.
Zeng-Ren
ZR
Zhao
Li-Jing
LJ
Zhang
Xin-Qi
XQ
He
Zhi-Yong
ZY
Zhang
Feng
F
Zhang
Fang
F
Li
Yong-Bin
YB
Pei
Yue-Ming
YM
Hu
Ming-Wei
MW
Wang
Xiao-Feng
XF
Sun
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism*
D008565:Membrane Proteins; D012333:RNA, Messenger; C516615:TMEM97 protein, human