RESUMO
Objective To observe the effect of 5-Aza-CdR on the proliferation and apoptosis of colon cancer cells and the expression of PTEN and to explore its mechanism Methods Different concentrations of 5-Aza-CdR (1, 2, 5,10 μmol/L) were used in vitro on HT-29 cells and the proliferation was detected by MTT assay and the apoptosis was detected by flow cytometry. PTEN mRNA and protein expression changes were observed by real-time PCR and Western blot. Results Different concentrations of 5-Aza-CdR (2, 5,10 μmol/L) could inhibit the proliferation of HT-29 cells with dose and time dependent manner. With the increase of time and dose, the inhibition rate of HT-29 cells increased gradually and the difference was significant. (P < 0.05). After 5-Aza-CdR treated for 48h , the apoptosis rates of HT-29 cells in control and 1 , 2 , 5 , 10 μmol/L group were 2.443 ± 0.210 1, 3.900 ± 0.665 1, 14.07 ± 1.206, 24.70 ± 2.506, and 30.60 ± 2.390 respectively, which were significantly increased and the apoptosis rate increased with the increase of dose , which was statistically significant (P < 0.05). The PTEN mRNA and protein expression of HT-29 cells were gradually increased when treated by different concentrations of 5-Aza-CdR. Conclusion 5-Aza-CdR might induce the expression of PTEN by demethylation and then inhibit the proliferation and induce apoptosis of HT-29 cells.
RESUMO
Objective To provide the basis for early detection and treatment of precancerous lesions of gastric carcinoma, and reference for early discovery, diagnoses and treatment of gastric cancer, by examining the differences of expression of Helicobaeter pylori (Hp), both in the gastric mueosa and in blood serum, between precancerous lesions of gastric carcinoma patients and gastric cancer patients. Methods Used immunechromatographic method and protein chip system to determine the expression of Hp in blood serum and used immunohistochemistry to detect the expression of Hp in gastric mucosa. The patients had been diagnosed by pathological methods, 170 patients with precancerous lesions of gastric carcinoma, 111 patients with gastric carcinoma and 31 patients with superficial gastritis. Results The expression of Hp was detected on every stage of precancerous lesions and gastric carcinoma. Compared with the detection rates of Hp, precancerous lesions of gastric carcinoma was higher than gastric carcinoma and superficial gastritis, superficial gastritis was the lowest. The differences of the three were significant (P<0.01). The detection rate of Hp in the gastric mueosa (86.2%, 66.7%, 38.7%, respectively)was obviously higher than in blood serum (80.6%, 52.3%, 32.3%, respectively). Conclusions Hp participates in the process of the precancerous lesions and gastric carcinoma. The expression of Hp both in the gastric mueosa and in the blood serum could be one of the indexes, which might report the process and curative effect of precancerous lesions. With such advantages as simple and applicability, the detection of Hp in the blood serum could be used widely. The endoscopy and the detection of Hp in the gastric mucosa are suggested for patients with Hp positive in the blood serum.