Preliminary screening for microsatellite instability and loss of heterozygosity in the deleted in colorectal cancer (DCC) gene among Filipino patients with colorectal adenocarcinoma

OBJECTIVE: This study aimed to detect the presence of microsatellite (MSI) and loss of heterozygosity (LOH) of the Deleted in Colorectal Cancer (DCC) gene in normal and tumor tissues of Filipino colorectal cancer patients and examine its correlation with age, gender, tumor grade, tumor stage and site of lesion.METHODS: Paired frozen normal and tumor tissues from thirtynine (39) patients with colorectal adenocarcinoma were used by polymerase chain reaction (PCR). Single strand conformation polymorphism - polyacrylamide gel electrophoresis (SSCP - PAGE) was used to determine MSI and restriction fragment length polymorphism (RFLP) was used to study LOH.RESULTS: Based on our data, out of the 39 patients, 10 showed LOH of the DCC gene using the LOH markers VNTR, M2 and M3, while no MSI was detected in the samples using the MSI markers BAT25 and BAT26. Correlation with clinicopathological characteristics showed that there is significance for the site of lesion. The LOH has correclation with tumor samples from the colon but not with those from the rectum.CONCLUSION: Preliminary screening for MSI and LOH of the DCC gene shows that occurrences of colorectal cancer among Filipino patients can be correlated with LOH of the DCC gene with colorectal cancer in a Filipino sample population.

Chromosomal aberrations among Filipino health workers at the chemotherapy oncology wards/clinics of a tertiary government hospital

INTRODUCTION: Chromosomal mutations are casual events in neoplasia development. Biomarker cytogenetic assays can determine exposure to mutagenic agents in occupational settings. This study assessed early biological marker chromosomal aberrations among health workers in the chemotheraphy oncology wards/ clinics, exploring its association to the subjects' occupational, environmental and baseline profile.METHODS: This was an IRB approved cross-sectional exploratory study among hospital personnel working in the chemotherapy oncology facility of a tertiary government hospital, who underwent structured interview and blood extraction for cytogenetic assay after informed consent. Study funds only permitted assay of 44 specimens of 144 planned sample size, hence, Stata 6.0 only analyzed data from 44 subjects.RESULTS: All 44 subjects had varying exposure to chemotherapy drug infusions. Of these, 79% had 1.0 breaks per cell (hypersensitive). Predominantly chromatid breaks (CTB), chromatid gaps (CTG), sister chromatid exhanges (SCE) were seen. No significant association was shown between mutagenic sensitivity and baseline characteristics, but with small sample size.CONCLUSION: 21% borderline to hypersensitive mutagenic sensitivity among oncology workers at the tertiary government hospital is relatively significant, despite small sample size, connoting a must preventive promotive practice of chemotherapy administration in the workplace.

A case of noonan syndrome associated with nephrotic syndrome, pituitary mass and pes varus

We report a case of a Filipino male diagnosed with Noonan syndrome on the basis of facial dysmorphism, chest deformity, short stature, mental and skeletal retardation, pulmonic stenosis and hypogonadism. In addition, he has three clinical features which are not known to be associated with the syndrome and are perhaps being reported for the first time:structurally normal kidneys with nephrotic syndrome, pituitary macroadenoma and pes varus.