Introduction: Methylation of promoter region of p16 leading to gene silencing has been implicated ina wide range of malignancies including lymphomas. In diffuse large B cell lymphoma (DLBCL) particularly, a varying percentage of epigenetic inactivation of p16 promoter region was observed ranging from 16 -54%. However, quantitative analysis of p16 promoter methylation in DLBCL has not been extensively studied in Malaysia. Objective: This study aims to quantitatively analyse p16 methylation in DLBCL samples using pyrosequencing technique. Methods: Genomic DNA was extracted from 16 formalin-fixed paraffin-embedded lymphoma tissue blocks from patients diagnosed with DLBCL. Samples were retrieved from Hospital Tengku Ampuan Afzan, Pahang and Hospital Universiti Sains Malaysia, Kelantan. Primers were designed to amplify bisulfite-treated DNA targeting p16 promoter region. Methylation status of 7 CpG sites was determined by pyrosequencing. Results: All the 16 samples studied showed promoter methylation of p16. The range of mean methylation percentage was between 18 to 81%. Conclusion: The present study has successfully measured the level of methylation of p16 in all 7 CpG sites despite the limitation in sample size. Since p16 methylation is a common event in our series of DLBCL cases, it is worth including a larger sample size in future studies to increase the chance of finding a significant correlation with clinical parameters.
Proteomic profiling is essential in understanding the pathophysiological process of multifactorial diseases such as acute myocardial infarction (AMI). Despite the increasing incidence of AMI in young adults, proteomic-based study focusing on young AMI remains limited. This study aimed to examine the plasma proteomic profiles of young adults with AMI compared to control subjects. We also hope to identify disease-specific protein biomarkers that contribute to the development of AMI in the young. Methods:Pooled plasma protein from 10 AMI patients aged 18 to 45 years and 10 age, gender and race-matched volunteers were separated using two-dimensional electrophoresis (2-DE). The spots proteins were analysed using the PD Quest analysis software. The spots proteins that were found to have been expressed differently between the two groups were identified by Matrix Assisted Laser Desorption/Ionization Time of Flight (MALDI-TOF) Mass Spectrometry. Results:There were three differently expressed proteins namely Apolipoprotein AI (Apo AI), Apolipoprotein AIV (Apo AIV) and Haptoglobin (p < 0.05). The expressions of these proteins were found to be increased in young patients with AMI compared to control subjects. Conclusion: The up regulation of Apo AI, Apo AIV and Haptoglobin in AMI patients indicate their important roles in the development of atherosclerotic disease. Thus, Apo AI, Apo AIV and Haptoglobin are potential disease biomarkers for young AMI.
Introduction: p16 gene plays an important role in the normal cell cycle regulation. Methylation of p16 has been reported to be one of the epigenetic events contributing to the pathogenesis of diffuse large B-cell lymphoma (DLBCL) which occurring at varying frequency. DLBCL is an aggressive and high-grade malignancy which accounts for approximately 30% of all non-Hodgkin lymphoma cases. However, little is known regarding the epigenetic alterations of p16 gene in DLBCL cases in Malaysia. Therefore, the objective of this study was to examine the status of p16 methylation in DLBCL. Methods: A total of 88 formalin-fixed paraffin-embedded DLBCL tissues retrieved from two hospitals located in the east coast of Malaysia, namely Hospital Tengku Ampuan Afzan (HTAA) Pahang and Hospital Universiti Sains Malaysia (HUSM) Kelantan, were chosen for this study. DNA specimens were isolated and subsequently subjected to bisulfite treatment prior to methylation specific-PCR. Two pairs of primers were used to amplify methylated and unmethylated regions of p16 gene. The PCR products were then separated using agarose gel electrophoresis and visualised under UV illumination. SPSS version 12.0 was utilised to perform all statistical analysis. Result: p16 methylation was detected in 65 of 88 (74%) samples. There was a significant association between p16 methylation status and patients aged >50 years old (p=0.04). Conclusion: Our study demonstrated that methylation of p16 tumor suppressor gene in our DLBCL cases is common and significantly increased among patients aged 50 years and above. Aging is known to be an important risk factor in the development of cancers and we speculate that this might be due to the increased transformation of malignant cells in aging cell population. However, this has yet to be confirmed with further research and correlate the findings with clinicopathological parameters.