Cytochrome P450 4B1 (CYP4B1) as a target in cancer treatment.

Cytochrome P450 4B1 (CYP4B1) plays crucial roles in biotransforming of xenobiotics. Its predominant extrahepatic expression has been associated with certain tissue-specific toxicities. However, the expressions of CYP4B1 in various cancers and hence their potential roles in cancer development were inclusive. In this work, existing knowledge on expression and regulation of CYP4B1 gene and protein, catalysis of CYP4B1, association of CYP4B1 with cancers, contradicting findings about human CYP4B1 activities as well as the employing CYP4B1 in suicide gene approach for cancer treatment were reviewed. To date, it appears that there is a wide spectrum of tissue distribution of CYP4B1 with lungs as the predominant sites. Several nuclear receptors are possibly responsible for regulating its gene expression. The involvement of CYP4B1 in cancer was considered via activation of procarcinogens and neovascularization. However, human CYP4B1 was found to be inactive due to a substitution of proline with serine at position 427. Suicide gene approach combining reengineered CYP4B1 and prodrug 4-ipomeanol (4-IPO) has shown a promising potential for targeted cancer therapy. Further studies should focus on the verification of human CYP4B1 catalytic activities. More compounds with similar structure as 4-IPO should be tested to identify more alternative agents for the suicide gene approach in cancer treatment.

Detection rate of colonic polyp among patients who had undergone colonoscopy at gastroenterology unit of Serdang Hospital, Malaysia.

OBJECTIVE: The aim of this study was to evaluate the demography, and to determine the detection rate of polyps, and detection rate of adenoma at a Malaysian tertiary hospital. METHODS: This is a retrospective study of all the patients who had undergone colonoscopy at Gastroenterology endoscopy unit, Serdang Hospital from 1st January 2010 to 31st December 2016. Patients who had a history of colorectal cancer, polyp or inflammatory bowel disease were excluded. Data collected which included patients' demography, indication for colonoscopy, colonoscopy finding, and histopathology results. Data was analysed with SPSS version 16. RESULTS: Among the 559 patients who had fulfilled the inclusion criteria (68 males, 44 females), 112 patients were found to have at least one polyp giving the polyp detection rate (PDR) of 20% and 168 polypectomies were performed. The PDR among male patients was higher than that of females (22.5% vs 17.1%, p<0.05). The detection rate of polyp was nearly equal in Malays, Chinese, Indians, and Others. The polyps were more common in those of age 40 years old and above (p<0.05), with the mean age of 63.0±1.5 years. The commonest morphology of polyp in our patients was sessile (58%) and majority was medium size (5-9mm). Otherwise, the polyps were commonly found in the distal colon those that in proximal colon (55.3% vs 38.7%, p<0.05). The adenoma detection rate (ADR) was 19.1% (107/559). CONCLUSION: The detection rate of colonic polyp from colonoscopy is 20% in our centre.

Endoscopic variceal ligation as primary prophylaxis for oesophageal variceal bleeding at a Malaysian tertiary hospital.

OBJECTIVE: Approximately one-third of patients with esophageal varices will develop bleeding which is a major cause of morbidity and mortality in patients with liver cirrhosis. Currently, the two most widely used modalities to prevent variceal bleeding are pharmacologic and oendoscopic variceal band ligation (EVL). However, EVL has been associated with significant complications. Hence we aim to evaluate and to identify the epidemiology, demography, and complications of EVL at our local Malaysian tertiary hospital. METHOD: This is a retrospective study of all the patients that had undergone endoscopic variceal surveillance at the Gastroenterology endoscopy unit, Serdang Hospital from 1st January 2015 to 31st March 2017. Patients' demography, aetiologies of liver cirrhosis, platelet level and international normalised ratio (INR) prior banding procedure, and the post EVL complications were recorded and further analysed with SPSS version 16. RESULTS: In this study, 105 patients were screened for varices. Fifty-five of them had undergone EVL, with a quarter of the patients requiring repeated ligation. There was a male preponderance with 76.4%. 56.4% of patients were in age from 40-59 years. The majority of our patients were of the Malay ethnicity. The major aetiology for liver cirrhosis in our patients was viral hepatitis with Hepatitis C (31.0%), and Hepatitis B (20.0%). Most of our patients had platelet count >50,000 and INR <1.5 prior to EVL. There was no major complication in all of our subjects. CONCLUSION: EVL is relatively safe and feasible treatment for prevention of oesophageal variceal bleeds with a low complication rate.