The relationship between Rac1 mRNA gene levels detected by FQ-RT-PCR and the metastasis in gastric carcinomas

Abstract

Objective To investigate the relationship between tumor metastasis-related Rac1 mRNA expression levels and gastric carcinomas metastasis, and to investigate the significance of Rac1 as a tumor marker for the evaluation of gastric carcinomas metastasis and distinguish between benign and malignant lesions. Methods This experiment used fluorescence quantitative RT-PCR TaqMan probe technology, chose Rac1 target gene fragment, which was cloned into the pET-20b (+) vector, constructed recombinant plasmid, and established the Rac1 mRNA fluorescence quantitative RT-PCR standard curve. And then the Rac1 mRNA levels were detected in 52 cases of gastric carcinoma tissues,52 cases of para-carcinoma tissues and 12 cases of benign gastric disease tissues. Its association with the metastasis of gastric carcinomas was analyzed. Results The positive rates and levels (median, P25-P75) of Rac1 mRNA were 100. 0% ,7.41 ×105 (3. 50 × 105-4. 36 × 106) copies/μl in gastric carcinomas, 46. 2% ,0(0-1.73 × 104) copies/μl in parscarcinoma tissues, 33. 3%, 0(0-3.55 × 103) copies/μl in benign tissues. The positive rates and leves(x2 =43.16,x2Xk-w = 64. 19, P ＜0. 01)among the three groups were significantly different. When the critical value of Rac1 mRNA level was 1.73 × 104 copies/μl determined by ROC, the sensitivity and specificity were 88. 5% and 100% respectively. When the critical value of Rac1 level was 7.49 × 105 copies/μl, the sensitivity and specificity were 57.9% and 78. 6% respectively. ConclusionThe Rac1 mRNA level detected with fluorescence quantitative RT-PCR has reference value to distinguish between benign and malignant lesions and evaluate gastric carcinoma metastasis. Key words: Stomach neoplasms; Neoplasm metastasis; Ras-related C3 botulinum toxin substrate 1 ; Reverse transcriptase polymerase chain reaction