17 research outputs found

    Telomerase Activation in Neoplastic Cell Immortalization and Tumour Progression

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    The unique ability of tumour cells to proliferate indefinitely is crucial to neoplastic progression as it allows these cells to express the aggressive properties of cancer without the censure of physiological ageing. This is in contrast to normal somatic cells which are subject to a “mitotic clock,” a phenomenon that has been linked to telomeric shortening after each round of cell replication, so that eventually the loss of genetic material reaches a critical stage and the cells undergo senescence and cell death. A study was conducted to investigate the role of telomerase, an RNA-containing enzyme that restores the telomere length, in the neoplastic cell immortalization and progression process. Fresh human tissue samples taken from excision specimens received by the Department of Pathology, University of Malaya Medical Centre, were investigated for telomerase activity using a commercial Telomerase PCR-ELISA kit (Boehringer Mannheim). Specimens comprised 33 breast lesions (10 infiltrating breast adenocarcinoma, 13 fibroadenoma and 10 non-neoplastic breast tissue), 27 colonic lesions (17 colonic adenocarcinoma and 10 non neoplastic colonic mucosa) and 42 cervical lesions (20 cervical carcinoma and 22 non neoplastic cervical tissues). Telomerase activity was found in 6 (60%) of 10 breast carcinomas, 6 (46%) of 13 fibroadenomas, none of the 10 nonneoplastic breast samples, 3 (17.6%) of 17 colon carcinomas and none of the 10 non-neoplastic colonic mucosal samples, 12 (60%) of 20 cervical carcinoma and 3 (13.6%) of 22 non-neoplastic cervical samples. 5/10 (50%) Stage I, 4/7 (57%) Stage II, 2/2 (100%) Stage III and 1/1 (100%) Stage IV cervical carcinomas showed telomerase activity. These findings support a contributory role for telomerase in tumourigenesis with activation occurring from neoplastic transformation and increasing with tumour progression

    Human papillomavirus in cervical cancers of Malaysians

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    With a cervical carcinoma remaining the second leading cancer among Malaysian women, it is imperative to clarify the prevalence of human papillomavirus (HPV)in this respect, considering the death of local information

    A comparison of 1995 WHO classification with 2003 ISN/RPS classification of lupus nephritis: a single centre observation

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    Background: In the past, lupus nephritis was histologically classified according to the 1995 WHO Classification. With the introduction of the 2003 ISN/RPS Classification, many nephropathology services converted to this new classification. This study was undertaken to compare both classification systems in a single centre practice. Methods: 103 consecutive adequate renal biopsies initially reported as lupus nephritis in the Department of Pathology, Faculty of Medicine, University of Malaya were reassessed using the criteria of both the 1995 WHO Classification and the 2003 ISN/RPS Classification. Results: The relative prevalence for each class using the WHO Classification were: Class I (1%), Class II (8.7%), Class III (6.8%), Class IV (60.2%), Class V (20.4%), Class VI (2.9%) while the prevalence using the 2003 ISN/RPS Classification were: Class I (1%), Class II (8.7%), Class III (6.8%), Class IV (61.2%), Class V (21.3%), Class VI (1%). Both classifications were essentially comparable with regards to Classes I, II and III. The differences in Classes IV, V and VI were significant in potential to alter patient management. The identification of segmental lesions (Class IV-S) over and above a global nephritis (Class IV-G) deserves more focused clinicopathological studies to gauge whether these groups have different clinical manifestations and outcomes. With regards Class V, the ISN/RPS system, by requiring that all mixed classes be stipulated in the diagnostic line, minimizes the chances of patients missing out on additional treatment. The ISN/RPS system has stricter criteria for Class VI, which again minimizes patients missing out on therapy. On the whole, the ISN/RPS system is more user-friendly as criteria are more clearly defined which translates to more benefits to patient care

    Proliferating cell nuclear antigen (PCNA) activity in hepatocellular carcinoma, benign peri-neoplastic and normal liver

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    Hepatocellular carcinoma (HCC) is among the ten most common cancers in Malaysian males. As cellular proliferation is an important feature of malignant transformation, we studied the proliferation pattern of normal and benign perineoplastic liver versus hepatocellular carcinoma in an attempt to further understand the tumour transformation process. 39 HCC (21 with accompanying and 18 without cirrhosis) histologically diagnosed at the Department of Pathology, University of Malaya Medical Centre between January 1992 and December 2003 were immunohistochemically studied using a monoclonal antibody to PCNA (Clone PC10: Dako). 20 livers from cases who had succumbed to traumatic injuries served as normal liver controls (NL). PCNA labeling index (PCNA-LI) was determined by counting the number of immunopositive cells in 1000 contiguous HCC, benign cirrhotic perineoplastic liver (BLC), benign perineoplastic non-cirrhotic (BLNC) and NL cells and conversion to a percentage. The PCNA-LI was also expressed as Ojanguren et al’s grades. PCNA was expressed in 10% NL, 38.9% BLNC, 76.2% BLC and 71.8% HCC with BLNC, BLC and HCC showing significantly increased (p<0.05) number of cases which expressed PCNA compared with NL. The number of BLC which expressed PCNA was also significantly increased compared with BLNC. PCNA-LI ranged from 0-2.0% (mean=0.2%) in NL, 0-2.0% (mean=0.3%) in BLNC, 0-3.6% (mean=0.7%) in BLC and 0-53.8% (mean=7.6%) in HCC with PCNA-LI significantly increased (p<0.05) only in HCC compared with BLC, BLNC and NL. Accordingly, all NL, BLC and BLNC showed minimal (<5% cells being immunopositive) immunoreactivity on Ojanguren et al’s grading system and only HCC demonstrated immunoreactivity which ranged up to grade 3 (75% of cells). From this study, there appears to be a generally increasing trend of proliferative activity from NL to BLNC to BLC and HCC. Nonetheless, BLNC and BLC, like NL, retained low PCNA-LI and only HCC had a significantly increased PCNA-LI compared with the benign categories. This is probably related to the malignant nature of HCC and may reflect the uncontrolled proliferation of the neoplastic hepatocytes

    The immunohistochemistry signature of mismatch repair (MMR) proteins in a multiethnic Asian cohort with endometrial carcinoma

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    Endometrial cancer is the most common gynecologic cancer in developed countries and is rising in incidence globally. Although the 5-year survival rates are >80%, factors beyond conventional pathologic features that predict clinical outcomes are still being elucidated. The aims of this study were to define the prevalence and associations of deficient mismatch repair (dMMR) protein expression (MLH1, MSH2, MSH6, PMS2) by immunohistochemistry in a multiethnic Southeast Asian cohort with endometrioid endometrial cancer. A total of 77 patients with adequate formalin-fixed paraffin-embedded specimens were identified. The sections were stained in 2 centers for 4 MMR proteins and examined by 2 independent specialist histopathologists. The mean age for the cohort was 58.6 yr, with 19.4% (15/77) of patients’ cancers showing loss of 2 MMR proteins. All 13 cancers with absent MLH1 showed PMS2 loss (13/15), whereas absent MSH2 correlated with MHS6 loss (2/15). There were no significant differences for dMMR cases in age, body mass index, histopathologic characteristics, and clinical outcomes. In dMMR cases, an overrepresentation of patients of Indian ethnic origin was observed compared with Chinese and Malays. These findings suggest that dMMR protein expression in a Southeast Asian endometrial cancer cohort does not correlate with disease outcomes

    Performance of transient elastography (TE) and factors associated with discordance in non-alcoholic fatty liver disease

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    To determine the accuracy of transient elastography (TE) and factors associated with discordance between TE and liver histology in patients with non-alcoholic fatty liver disease(NAFLD).The accuracy of TE was assessed and compared with the aspartate aminotransferase-to-platelet ratio index (APRI) in patients with histologically proven NAFLD. Factors associated with discordance between liver histology and TE were analyzed.Altogether 131 patients with a mean age of 49.9 years, including 69 men and 62 women, with NAFLD underwent liver stiffness measurement (LSM) by TE. Among all patients, 120 (91.6%) had a successful LSM with an interquartile to median ratio of 0.15. The accuracy of TE in detecting ≥F3 and F4 fibrosis, assessed by the area under the receiver operating characteristic curve, were 0.77 and 0.95, respectively. The sensitivity and specificity of the optimal LSM cut-off values for detecting ≥F3 fibrosis (sensitivity 70.4% and specificity 66.6%) and F4 (sensitivity 87.5% and specificity 89.3%) were modest, but better than those of APRI. Discordance between TE and histology for fibrosis grading was observed in 22.5% of patients, but it could not be explained by body mass index, alanine aminotransferase level, the length of the biopsied specimens or the grade of steatosis.TE plays an important role in the detection of advanced fibrosis and cirrhosis in patients with NAFLD and its accuracy does not appear to be influenced by components of the disease

    Early Diagnosis of Myocardial Dysfunction in Patients With Hematological Malignancies Submitted to Chemotherapy. Preliminary Results.

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    Early Diagnosis of Miocardial Dysfunction in Patients with Hematological Malignancies Submitted to Chemotherapy. Preliminary \ud Background: Considering the current diagnostic improvements and tl1erapeutic approaches, patients witl 1 cancer can now be healed or keep the disease under control, still, the chemotherapy may cause heart damage, evolving to Congestive Heart Failure. Recognition of those changes increases the chances of control the endpoints; hence, new parameters of cardiac and fluid mechanics analysis have been used to assess the myocardial function, pursuing an earlier diagnosis of the cardiac alterations. This study aimed to detect early cardiac dysfunction consequently to chemotherapy in patients with hematological malignancies (HM). Methods: Patients with leukemia and lymphoma, submitted to chemotherapy, without knowing heart diseases were studied. Healthy volunteers served as the control group. Conventional 2DE parameters of myocardial function were analyzed. The peak global longitudinal, circumferential and radial left ventricular (LV) strain were deternined by 2D and 3D speckle tracking (STE); peak area strain measured by 3D STE and LV torsionn, twisting rate, recoil / recoil rate assessed by 2D STE. The LV vortex formation time (VFT) during the rapid diastolic filling was estimated by the 2D mitral valve (MV) planimetry and Pulsed Doppler LV inflow by: VFT- 4(1-β) / π x α3 x LVEF Where 1- β is the E wave contribution to the LV stroke volume and α3 is a volumetric variable related to the MV area. The statistical level was settled on 5%. Results: See Table. Conclusion: Despite the differences between the two groups concerning the LVESV, LVEF and E´, those parameters still are in the normal range when considering the patients submitted to chemotherapy; thus, in the clinical setting, they are not so noticeable. The 3D GLS was smaller among the patients, oppositely to the 2D GLS, suggesting that the former variable is more accurate to assess tlhe LV systolic function. The VFT is a dimensionless measure of the optimal vortex development inside the LV chamber; reflecting the efficiency of the diastolic filling and, consequently, blood ejection. This index showed to be diminished in patients with HM submitted to chemotherapy, indicating an impairment of the in1pulse and thrust, hence appearing to be a very early marker of diastolic and systolic dysfunction in this group.CNP

    Research on cancer diagnosis in Malaysia: current status.

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    Cancer is a major morbidity and mortality concern in Malaysia. Based on National Cancer Registry data, the Malaysian population is estimated to bear a cancer burden of about 40,000 new cases per year, and a cumulative lifetime risk of about 1:4. Cancer research in Malaysia has to consider needs relevant to our population, and resources constraints. Hence, funding bodies prioritise cancers of high prevalence, unique to our community and posing specific clinical problems. Cancer diagnosis is crucial to cancer management. While cancer diagnosis research largely aims at improvements in diagnostic information towards more appropriate therapy, it also impacts upon policy development and other areas of cancer management. The scope of cancer diagnosis upon which this paper is based, and their possible impact on other R&D areas, has been broadly categorized into: (1) identification of aetiological agents and their linkages to the development of precancer and cancer (impact on policy development, cancer prevention and treatment), (2) cancer biology and pathogenesis (impact on cancer prevention, treatment strategies and product development), (3) improvements in accuracy, sensitivity and specificity in cancer detection, monitoring and classification (impact on technology development) and (4) prognostic and predictive parameters (impact on treatment strategies). This paper is based on data collected by the Working Group on Cancer Diagnosis Research for the First National Conference on Cancer Research Coordination in April 2004. Data was collated from the databases of Institutions/Universities where the authors are employed, the Ministry of Science, Technology and Innovation (MOSTI) and targeted survey feedback from key cancer researchers. Under the 7th Malaysia Plan, 76 cancer projects were funded through the Intensified Research in Priority Areas (IRPA) scheme of MOSTI, amounting to almost RM15 million of grant money. 47(61.8%) of these projects were substantially in cancer diagnosis, accounting for 65.6% (RM 9.7 million) of cancer project funds. The 8th Malaysia Plan saw a change in research strategy. The IRPA agency fielded several top-down projects which encouraged a multicentre and multidisciplinary approach. This resulted in larger funding per project i.e. RM32 million for 49 projects. There was also a surge of interest in drug development and natural products. Because of this shift in direction, cancer diagnosis projects constituted only 51% of IRPA-funded cancer projects. Nonetheless funding for cancer diagnosis research has exceeded that of the 7th Malaysia Plan, being RM12.5 million by March 2004. The majority of such research is carried out at the Universities, engaging a large number of young scientists and postgraduate students (51 MSc and 21 PhD). A lot of research findings presented at scientific meetings have not yet been published and there is a glaring shortage of patents and commercialization of research findings (such as creation of test kits). Because diagnosis is very much a part of clinical practice, many researchers felt satisfied and confident that their work will be translated into practice and will significantly improve diagnostic services in Malaysia. National guidelines and consensus development on at least three malignancies i.e. breast cancer, oral cancer and lymphoma, have substantial basis in local R&D work. Problems encountered in research included (1) insufficient funding to realize research objectives, (2) lack of local expertise (most research assistants are inexperienced BSc graduates with no or minimal research experience), (3) inadequate technical support from vendors during equipment failure, (4) inexperienced Institutional development units to assist in product development, (5) lack of venture capital for commercialization of findings, and (6) inadequate incentives to undertake research. Researchers pointed out that plans to promote research should include the establishment of (1) regional and national cancer tissue banks, (2) a National Cancer Research Institute, (3) a dedicated cancer research fund, (4) a registry of cancer researchers, (5) national research coordinators, (6) improved coverage by the National Cancer Registry, (7) more international collaboration, (8) a better career structure for researchers, (9) improved Institutional support for product realization, and (10) better recognition for cancer researchers
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