A single nucleotide polymorphism in the matrix metalloproteinase 2 promoter is closely associated with high risk of nasopharyngeal carcinoma in Cantonese from southern China.

Matrix metalloproteinase 2 (MMP2) has been shown to play an important role in several steps of cancer development. The -1306C/T polymorphism of the MMP2 gene displays a strikingly lower promoter activity than the T allele, and the CC genotype in the MMP2 promoter has been reported to associate with the development of several cancers. To assess the contribution of the MMP2 -1306C/T polymorphism to the risk of nasopharyngeal carcinoma (NPC), we conducted a case-control study and analyzed MMP2 genotypes in 370 patients with NPC and 390 frequency-matched controls using real-time PCR-based TaqMan allele analysis. We found that subjects with the CC genotype had an increased risk (OR = 1.55, 95% CI = 1.05-2.27) of developing NPC compared to those with the CT or TT genotypes. Furthermore, we found that the risk of NPC was markedly increased in subjects who were smokers (OR = 15.04, 95% CI = 6.65-33.99), heavy smokers who smoked ≥ 20 pack-years (OR = 18.66, 95% CI = 7.67-45.38), or young (<60 years) at diagnosis (OR = 1.52, 95% CI = 1.01-2.29). Our results provide molecular epidemiological evidence that the MMP2 -1306C/T promoter polymorphism is associated with NPC risk, and this association is especially noteworthy in heavy smokers.

[Therapeutic effects of Tiaozhong Granule on esophagus mucous membrane in rats with mixed reflux esophagitis and the mechanisms].

OBJECTIVE: To explore the mechanism of Tiaozhong Granule (TZG), a compound traditional Chinese herbal medicine, in treating rats with mixed reflux esophagitis. METHODS: Fifty-eight SD rats were randomly divided into untreated group (n=12), sham-operated group (n=10), TZG-treated group (n=12), Banxia Xiexin Decoction (BXXXD)-treated group (n=12) and cisapride-treated group (n=12). Mixed reflux esophagitis was induced by esophago-duodenum end-to-side anastomosis. Four weeks later, the rats were orally administered twice daily for 12 days. Pathological changes of esophagus mucous membrane were observed by using HE staining. The expressions of proliferating cell nuclear antigen (PCNA) and p53 in the esophagus tissue were detected by immunohistochemical SABC method. Spectrophotometric method was used to detect the content of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in serum. RESULTS: Compared with the untreated group, pathological changes of esophagus mucous membrane were relieved in different degrees in TZG-treated group, BXXXD-treated group and cisapride-treated group. Content of MDA and expressions of PCNA and p53 were obviously decreased in the three treated groups (P<0.01), and the activities of SOD and GSH-Px were significantly increased in the three treated groups (P<0.05, P<0.01). TZG had better effects than cisapride in decreasing the content of MDA and increasing the activities of SOD and GSH-Px (P<0.05). TZG was better in aspect of reducing the expressions of PCNA and p53 than BXXXD and cisapride tablets (P<0.05). CONCLUSION: Tiaozhong Granule can treat mixed reflux esophagitis in rats, and its action mechanisms may be associated with decreasing the expressions of PCNA and p53 in esophagus mucous membrane, reducing the content of MDA and increasing the activities of SOD and GSH-Px in serum.