The Clinical And Biological Significance Of HTERT And Rb Protein Expression In Gastric Cancer

Objective To investigate the role of human telomerase reverse transcriptase (hTERT) and Rb Protein expression in the process of gastric carcinogenesis in relation to biological behavior, and evaluate the early diagnostic significance of the detection of hTERT protein expression in gastric cancer.Methods The expression of hTERT and Rb Protein was measured in formalin-fixed, paraffin-embedded gastric cancer specimens from 50 patients in gastric cancer group, 25 patients in precancerous lesions group, and 11 healthy people in normal control group by using the strept avidin biotin peroxidase method, and their correlations to clinicopathologic features were analyzed.Results The positive rate of hTERT Protein expression in 50 specimens of gastric cancer group were 86.0% (43/50), significantly higher than that in 28.0% (7/25) of precancerous leision group (P<0.001) and in 0.0% (0/11) of normal control group( P<0.001). The sensitivity, specificity and accuracy of detection of hTERT were 86.0%, 80.6%, 83.7% respectiviely. Rb Protein were expressed in 58.0% (29/50) of gastric cancer group, significantly lower than that in 88.0% (22/25) of precancerous lesion group (P<0.01)and in 100.0% (11/11) of normal control group(P<0.01). The significant difference in positive rates of hTERT and Rb were not found between different pathological types: Tubular adenocarcinoma, Papillary adenocarcinoma ,Mucinous adenocarcinoma, Signet-ring cell carcinoma, low differentiated carcinoma, and undifferentiated carcinoma. The positive expressions of hTERT were correlated with the degree ofdepth of invasion,lymph node metastasis and clinical stage of gastric carcinoma(P<0.05). but not with age, sex, sites, tumor size, morphology and the degree of differentiation (P>0.05). The abnormal expressions of Rb protein were correlated with the lymph node metastasis and clinical stage of gastric carcinoma (P<0.05). but not with age, sex, sites, tumor size, morphology, the degree of depth of invasion and the degree of differentiation (P>0.05).Conclusions There were a positive correlation between the expression of hTERT and carcinogenesis of gastric cancer and a negative correlation between the expression of Rb protein and carcinogenesis of gastric cancer. This study suggested that hTERT may be a sensitive and specific tumor marker of gastric cancer. The detection of hTERT may be helpful in early diagnosis of gastric cancers. The detection of hTERT and Rb protein may also be helpful in evaluating the prognosis of gastric cancers. The expressions of hTERT protein were negatively correlated with the expressions of Rb protein (P<0.05). It suggested that the deficiency of Rb protein may be one of the acting pathways of hTERT. Immunohistoche -mistry method was convenient, economical, and cost less time and money.