Potent in vitro synergism of fusidic acid (FA) and berberine chloride (BBR) against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA).

It was found in the present study that combined use of fusidic acid (FA) and berberine chloride (BBR) offered an in vitro synergistic action against 7 of the 30 clinical methicillin-resistant Staphylococcus aureus (MRSA) strains, with a fractional inhibitory concentration (FIC) index ranging from 0.5 to 0.19. This synergistic effect was most pronounced on MRSA 4806, an FA-resistant isolate, with a minimum inhibitory concentration (MIC) value of 1,024 µg/ml. The time-kill curve experiment showed that FA plus BBR yielded a 4.2 log10 c.f.u./ml reduction in the number of MRSA 4806 bacteria after 24-h incubation as compared with BBR alone. Viable count analysis showed that FA plus BBR produced a 3.0 log10 c.f.u./ml decrease in biofilm formation and a 1.5 log10 c.f.u./ml decrease in mature biofilm in viable cell density as compared with BBR alone. In addition, phase contrast micrographs confirmed that biofilm formation was significantly inhibited and mature biofilm was obviously destructed when FA was used in combination with BBR. These results provide evidence that combined use of FA and BBR may prove to be a promising clinical therapeutic strategy against MRSA.

Aberrant DNA methylation of P16, MGMT, and hMLH1 genes in combination with MTHFR C677T genetic polymorphism and folate intake in esophageal squamous cell carcinoma.

AIM: The present case-control study was conducted to explore the association of MTHFR gene polymorphism and relations of P16, MGMT and HMLH1 to MTHFR and folate intake. METHODS: A total of 257 cases of esophageal squamous cell carcinoma confirmed by histopathological examination were collected. Genotyping of P16, MGMT and HMLH1 was accomplished by methylation-specific polymerase chain reaction (PCR) after sodium bisulfate modification of DNA and the MTHFR C677T genetic polymorphism was detected by PCR- restriction fragment-length polymorphism (PCR-RFLP). RESULTS: The proportions of DNA hypermethylation in P16, MGMT and hMLH1 in cancer tissues were significantly higher than in paracancerous normal tissue. The proportion of hypermethylation in at least one gene was 88.5% in cancer tissue, and was also significantly higher than that in paracancerous normal tissue. Our finding showed individuals with homozygotes (TT) of MTHFR C677T had significant risk of DNA hypermethylation of MGMT in cancer tissues, with an OR (95% CI) of 3.15 (1.12-6.87). Similarly, patients with high intake of folate also showed a slight high risk of DNA methylation of MGMT, with OR (95% CI) of 2.03 (1.05-4.57). CONCLUSION: Our study found the P16, MGMT and hMLH1 demonstrate a high proportion of hypermethylation in esophageal squamous cell cancer cancer tissues, which might be used as biomarkers for cancer detection.

Glulathione-S-transferases gene polymorphism in prediction of gastric cancer risk by smoking and Helicobacter pylori infection status.

AIM: To evaluate the association of glutathione S-transferases gene polymorphisms with the risk of gastric cancer, with reference to smoking and Helicobacter pylori infection. METHODS: We conducted a 1:1 matched case-control study with 410 gastric cancer cases and 410 cancer-free controls. Polymorphisms of GSTM1, GSTT1 and GSTP1 were determined using PCR-CTPP. RESULTS: The GSTM1 and GSTT1 null genotypes were significantly associated with the risk of gastric cancer after adjusting for potential confounding factors (OR=1.68, 95% CI=1.32-2.23 for null GSTM1, OR=1.73; 95% CI=1.24-2.13 for null GSTT1). The combination of null GSTM1 and null GSTT1 conferred an elevated risk (OR=2.54, 95% CI=1.55-3.39). However, no association was found for GSTP1 polymorphism The smoking modified the association of GSTM1 and GSTT1 null genotypes with the risk of gastric cancer. CONCLUSION: GSTM1 and GSTT1 null genotypes are associated with increased risk of gastric cancer, and smoking modifies the association.

Expression of matrix metalloproteinase 2 and its tissue inhibitor in oral squamous cell carcinoma.

The aim of this study is to investigate the expression of matrix metalloproteinase 2 (MMP-2) and the tissue inhibitor of metalloproteinase 2 (TIMP-2) in oral squamous cell carcinoma (OSCC) and adjacent normal tissues, and explore the role of MMP-2 and TIMP-2 in carcinoma metastasis and invasion. Expression of MMP-2 and TIMP-2 was evaluated in 40 cases with semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical techniques. The values of MMP-2/beta-actin and TIMP-2/beta-actin in OSCC were significantly higher than those in adjacent normal tissues 2 cm and > or = 5 cm from carcinoma tissues (p<0.05). The results of immunohistochemical analysis show that the positive expression of MMP-2 and TIMP-2 protein in tumor tissues (60.0 and 52.5%) was higher than that in adjacent normal tissues 2 cm (30.0 and 22.5%) and 5 cm (22.5 and 25.0%) from cancer tissues, and the difference was significant p<0.05). The expression of MMP-2 and TIMP-2 was related to the differentiation degree of tumor cells, metastatic lymph node status and stage of carcinoma, but not related to the age and gender of patients, or location of the carcinoma. Therefore, MMP-2 and TIMP-2 may play important roles in the invasion and metastasis of OSCC.

[Examination of serum hyaluronic acid level in patients with oral and maxillofacial malignancy].

OBJECTIVE: To determine the level of hyaluronic acid (HA) in serum of patients with oral and maxillofacial malignancy and to investigate the correlation between the levels of serum HA and stage of the malignant lesions and treatment response. METHODS: 44 patients with oral and maxillofacial malignancy were analyzed and 24 healthy individuals served as controls. Venous blood was collected from the patients before treatment and the healthy individuals. One week after therapy, venous blood were collected in 24 patients once again. Serum levels of HA were measured with quantitative radioimmunoassay (RIA). RESULTS: Before treatment, the serum HA concentration in patients with oral and maxillofacial malignancy was significantly higher than that of the controls (P < 0.05). Also, the serum HA concentration in patients with OSCC was significantly higher than that of the controls (P < 0.05). No difference was noted in serum HA concentration between patients with salivary ACC and the control group (P > 0.05). The serum HA concentration of patients in stage III and IV was significantly higher than that of patients in stage I and II (P < 0.05). Serum HA levels decreased in patients after a complete treatment, but the difference was not significant (P > 0.05). CONCLUSION: Serum levels of HA may be useful in diagnosis of OSCC and was associated with clinical stages in patients with oral and maxillofacial malignancy. However, it may not be contributory to monitoring treatment response in patients with oral and maxillofacial malignancy.