OBJECTIVETo investigate the association of p15 and pl6 genes deletion and STKI5 gene overexpression in primary hepatocellular carcinoma (PHC).

METHODSThe carcinoma tissue and the adjacent normal tissue were taken from 30 PHC patients during operations who had had neither chemotherapy nor radiotherapy preoperatively. DNA was extracted from the tissues and PCR was used to determine the homozygous deletion of p15 exon2 (pl5E2) and pl6 exon 2 (pl6E2). RNA was extracted, cDNA was synthesized by RT-PCR, and the expression of STKI5 gene was tested by PCR. Beta-actin was used as an internal control. Average density value (ADV) of STK15 gene and that of beta-actin gene were determined in both carcinoma tissue and the adjacent normal tissue.

RESULTSThe rate of p15E2 deletion was 13.3% (4/30) and the rate of p16E2 deletion was 16.7% (5/30) in the carcinoma tissue. The p15E2 and pl6E2 co-deletion rate was 6.7% (2/30). In 19 of the 30 cases (63.3%) the expression of STK15 gene in carcinoma tissue was higher than that in the adjacent normal tissue. The ratio of ADV of STK15 gene to ADV of beta-actin gene (1.53+/-0.31) in the carcinoma tissue was significantly higher than that (0.91+/-0.25) in the paired adjacent normal tissue (t = 2.86).

CONCLUSIONThe homozygous deletion of p15E2 and p16E2 and overexpression of STKI5 gene may play a role in the oncogenesis and malignant progression of PHC.