Relationship between expression of Bcl-2 and p53 protein and CagA+Helicobacter pylori in gastric cancer

Relationship between expression of cyclooxygenase-2 and cagA+ Helicobacter pylori infection in gastric carcinoma

AIM: To explore the relations of cagA⁺Helicobacter pylori infection with the expression of cyclooxygenase-2 (COX2) in human gastric carcinogenesis.

METHODS: In situ polymerase chain reaction (PCR) was used to detect the expression of H. pylori cagA gene, and immunohistochemical technique was used to detect the expression of COX2 in 56 patients with gastric carcinoma.

RESULTS: The rates of cagA⁺H. pylori infection and COX2 expression were 55.4% and 71.4%, respectively, in gastric carcinoma. The level of COX2 expression was significantly higher in the gastric carcinoma of Ⅲ-Ⅳ stage than Ⅰ-Ⅱ stage (14/30 vs 5/26, P <0.05), and was also higher in gastric carcinoma with lymph node metastasis than that without lymph node metastasis (4/19 vs 15/37,P <0.01). CagA⁺H. pylori infection was not correlated with TNM stage and lymph node metastasis in gastric carcinoma (P >0.05). The level of COX2 expression was significantly higher in cagA⁺H. pylori group than that in cagA^-H. pylori group (15/31 vs 4/25, P <0.05).

CONCLUSION: CagA⁺H. pylori infection is not related with the malignant progression of gastric carcinoma, but COX2 expression is involved in the carcinogenesis and malignant progression of gastric carcinoma. CagA⁺H. pylori infection up-regulates the expression of COX2 in gastric cancer.

Detection of Helicobacter pylori from gallbladder mucosa in patients with chronic cholecystitis

AIM: To study whether Helicobacter pylori (H. pylori) located in gallbladders of chronic cholecystitis.

METHODS: Using Warthy-Starry (W-S) stain and immunohistochemical stain with anti-H. pylori antibody, we screened paraffin specimens in 524 cases of cholecystitis. Helicobacter pylori urease gene A (HPUA) and Helicobacter pylori urease gene B (HPUB) were analyzed by polymerase chain reaction (PCR) in the fresh tissue specimens in 81 cases of cholecystitis.

RESULTS: H. pylori-like bacteria were found in 13.55% of gallbladders in cholecystitis patients using W-S stains; Meanwhile, positive bacteria for H. pylori antibody were also found in 7.1% of gallbladder in patients with cholecystitis using immunohistochemistry. Both of HPUA and HPUB were positive in 11 of 81 gallbladders by PCR, only 4 cases positive for HPUA, and 7 cases with HPUB positive.

CONCLUSION: H. pylori certainly exists in gallbladders in some patients with chronic cholecystitis.

Characteristics of Helicobacter pylori from gallbladder mucosal scrapings in patients with chronic cholecystitis

AIM: To study the characteristics of Helicobacter pylori (H. pylori) isolated from gallbladder mucosal scrapings in patients with chronic cholecystitis.

METHODS: H. pylori -like bacteria isolated from gallbladder mucosal scrapings and stomach in 81 patients with chronic cholecystitis were identified as H. pylori. The amplification bands were observed by PCR method using the H. pylori -specific primers, HPUA, and HPUB. Ultrastructural characteristics were also examined with transmission electron microscope.

RESULTS: The urease activity of H. pylori derived from cholecyst was lower than that from the patients' stomach. The other characteristics were the same in both cholecystic H. pylori and gastric H. pylori.

CONCLUSION: It is most likely that H. pylori excretes from the stomach into the duodenum and then is retrogradely transferred to the gallbladder by the ascending routes of infection.