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Long-term administration of tocotrienols and tumor-marker enzyme activities during hepatocarcinogenesis in rats

Rahmat A, Ngah WZ, Shamaan NA, Gapor A, Abdul Kadir K

Nutrition, 1993 May-Jun;9(3):229-32.
PMID: 8102564

The effects of long-term administration of tocotrienol on hepatocarcinogenesis in rats induced by diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) were investigated by determining the activities of gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), glutathione S-transferases (GSTs), and glutathione (GSH) levels in blood and liver. Twenty-eight male 7- to 8-wk-old Rattus norwegicus rats, weighing 120-160 g, were used in this study. The rats were divided into four treatment groups: a control group on a basal diet, a group fed a basal diet supplemented with tocotrienol (30 mg/kg food), a group treated with DEN/AAF, and a group treated with DEN/AAF and fed a diet supplemented with tocotrienol (30 mg/kg food). Blood was collected monthly, and GGT, ALP, and GSH levels were determined. The rats were killed after 9 mo, and the livers were examined morphologically. Grayish white nodules (2/liver) were found in all the DEN/AAF-treated rats (n = 10), but only one of the rats treated with DEN/AAF and supplemented with tocotrienol (n = 6) had liver nodules. A significant increase in the level of blood and liver GSH, ALP, and GGT activities was observed in the DEN/AAF-treated rats. Liver GSTs were similarly increased with DEN/AAF treatment. Tocotrienol supplementation attenuated the impact of the carcinogens in the rats.

Matched MeSH terms: Cell Transformation, Neoplastic/drug effects*; Cell Transformation, Neoplastic/metabolism
Fulltext Viability reduction and Rac1 gene downregulation of heterogeneous ex-vivo glioma acute slice infected by the oncolytic Newcastle disease virus strain V4UPM

Mustafa Z, Shamsuddin HS, Ideris A, Ibrahim R, Jaafar H, Ali AM, et al.

Biomed Res Int, 2013;2013:248507.
PMID: 23586025 DOI: 10.1155/2013/248507

Oncolytic viruses have been extensively evaluated for anticancer therapy because this virus preferentially infects cancer cells without interfering with normal cells. Newcastle Disease Virus (NDV) is an avian virus and one of the intensively studied oncolytic viruses affecting many types of cancer including glioma. Nevertheless, the capability of NDV infection on heterogeneous glioma tissue in a cerebrospinal fluid atmosphere has never been reported. Recently, Rac1 is reported to be required for efficient NDV replication in human cancer cells and established a link between tumourigenesis and sensitivity to NDV. Rac1 is a member of the Rho GTPases involved in the regulation of the cell migration and cell-cycle progression. Rac1 knockdown leads to significant inhibition of viral replication. In this work, we demonstrated that NDV treatment led to significant reduction of tumour tissue viability of freshly isolated heterogeneous human brain tumour slice, known as an ex vivo glioma acute slice (EGAS). Analysis of gene expression indicated that reduced tissue viability was associated with downregulation of Rac1. However, the viability reduction was not persistent. We conclude that NDV treatment induced EGAS viability suppression, but subsequent downregulation of Rac1 gene may reduce the NDV replication and lead to regrowth of EGAS tissue.

Matched MeSH terms: Cell Transformation, Neoplastic
Detection of somatic mutations in the mitochondrial DNA control region D-loop in brain tumors: The first report in Malaysian patients

Mohamed Yusoff AA, Mohd Nasir KN, Haris K, Mohd Khair SZN, Abdul Ghani ARI, Idris Z, et al.

Oncol Lett, 2017 Nov;14(5):5179-5188.
PMID: 29098023 DOI: 10.3892/ol.2017.6851

Although the role of nuclear-encoded gene alterations has been well documented in brain tumor development, the involvement of the mitochondrial genome in brain tumorigenesis has not yet been fully elucidated and remains controversial. The present study aimed to identify mutations in the mitochondrial DNA (mtDNA) control region D-loop in patients with brain tumors in Malaysia. A mutation analysis was performed in which DNA was extracted from paired tumor tissue and blood samples obtained from 49 patients with brain tumors. The D-loop region DNA was amplified using the PCR technique, and genetic data from DNA sequencing analyses were compared with the published revised Cambridge sequence to identify somatic mutations. Among the 49 brain tumor tissue samples evaluated, 25 cases (51%) had somatic mutations of the mtDNA D-loop, with a total of 48 mutations. Novel mutations that had not previously been identified in the D-loop region (176 A-deletion, 476 C>A, 566 C>A and 16405 A-deletion) were also classified. No significant associations between the D-loop mutation status and the clinicopathological parameters were observed. To the best of our knowledge, the current study presents the first evidence of alterations in the mtDNA D-loop regions in the brain tumors of Malaysian patients. These results may provide an overview and data regarding the incidence of mitochondrial genome alterations in Malaysian patients with brain tumors. In addition to nuclear genome aberrations, these specific mitochondrial genome alterations may also be considered as potential cancer biomarkers for the diagnosis and staging of brain cancers.

Matched MeSH terms: Cell Transformation, Neoplastic
Fulltext Targeting bladder cancer stem cells using Newcastle disease virus

Arcana Thirumorthy, De-Ming Chau, Khatijah Yusoff, Abhi Veerakumarasivam

Malaysian Journal of Medicine and Health Sciences, 2019;15(108):24-24.
MyJurnal

Introduction: Bladder cancer is associated with high risk of tumour recurrence and therapeutic resistance. Cancer stem cells (CSC) within a particular tumour are postulated to drive tumorigenesis and influence tumour behaviour. Recent studies have shown that Newcastle disease virus (NDV) is able to selectively kill and exert a strong oncolytic effect against various cancer types. However little is known about the oncolytic effect of NDV against CSC. In this study, the oncolytic effect of NDV against putative bladder CSC was examined. Methods: Putative bladder CSC was selectively grown in the form of 3D-spheroids from six different bladder cancer cell lines. The spheroid cells were characterised for their stemness properties to ensure that these cells truly represent CSC. This was conducted via the analysis of CSC associated genes and cell surface markers expression. Subsequently, the oncolytic effect of the wild-type NDV-AF2240 strain against the bladder cancer spheroids was investigated. Results: All the spheroids expressed significantly high levels of CSC-associated genes. Flow-cytometry analysis revealed that the expression pattern of the CSC-associated surface markers was different in the spheroid cells; suggesting heterogeneity in the expression signatures of these cells. The infection of spheroids with NDV showed that the NDV was able to target bladder cancer spheroids but there was a spectrum of response across the different spheroids. Intriguingly, NDV was able to persistently infect bladder cancer spheroids that were not sensitive towards NDV infection as the presence of NDV viral genes were detected in the spheroid cells. The NDV persistently infected bladder cancer spheroids were resistant to superinfection and developed an antiviral state by expressing low levels of interferon-beta (IFN-b). NDV persistency of infection affects the process of epithelial to mesenchymal transition (EMT) of cancer cells as the spheroid forming ability of an established NDV persistently infected bladder cancer cell line, EJ28-PI was shown to be impaired. The EJ28-PI cells expressed significantly high levels of the EN2 gene. Knockdown of the EN2 expression reduced the viability of EJ28-PI cells; suggesting a role for EN2 in mediating NDV persistency of infection in cancer cells. Conclusion: Bladder CSC gene expression signatures influence the efficacy of NDV-mediated oncolysis. Our current work is focused on identifying genes and signalling pathways that influence NDV-mediated oncolysis us-ing whole-transcriptomic sequencing. The findings of this study can potentially be used to enhance the efficacy of NDV-mediated oncolysis and accelerate the translation of NDV as an oncotherapeutic agent in the clinic.

Matched MeSH terms: Cell Transformation, Neoplastic
Fulltext Roles of EphA2 Receptor in Angiogenesis Signaling Pathway of Glioblastoma Multiforme

Baharuddin WNA, Yusoff AAM, Abdullah JM, Osman ZF, Ahmad F

Malays J Med Sci, 2018 Nov;25(6):22-27.
PMID: 30914876 DOI: 10.21315/mjms2018.25.6.3

Glioblastoma multiforme (GBM) is one of the most common primary brain tumours in adults, accounting for almost 65% of all cases. Among solid tumours, GBM is characterised by strong angiogenesis, including the highest degree of vascular proliferation and endothelial cell hyperplasia. Despite numerous improvements in existing treatment approaches, the prognosis of GBM patients remains poor, with a mean survival of only 14.6 months. Growing evidence has shown significant overexpression of the ephrin type-A receptor 2 (EphA2) receptor in various malignancies, including GBM, as well as a correlation to poor prognoses. It is believed that EphA2 receptors play important roles in mediating GBM tumourigenesis, including invasion, metastasis, and angiogenesis. Despite the clinical and pathological importance of tumour-associated vasculature, the underlying mechanism involving EphA2 is poorly known. Here, we have summarised the current knowledge in the field regarding EphA2 receptors' roles in the angiogenesis of GBM.

Matched MeSH terms: Cell Transformation, Neoplastic
Fulltext Palm oil thorn-induced squamous cell carcinoma with underlying burns scar

Qi Qi C, Ajit Singh V

BMJ Case Rep, 2012;2012.
PMID: 22865804 DOI: 10.1136/bcr-2012-006401

Marjolin's ulcers are malignancies that arise from previously traumatised, chronically inflamed or scarred skin. We present a case with childhood burns, who had repeated irritation of his forearm skin with palm oil thorns that eventually led to malignant change.

Matched MeSH terms: Cell Transformation, Neoplastic*
Nuclear factor-kappa B as a promising target for selenium chemoprevention in rat hepatocarcinogenesis

Alwahaibi NY, Budin SB, Mohamed J, Alhamdani A

J Gastroenterol Hepatol, 2010 Apr;25(4):786-91.
PMID: 20492335 DOI: 10.1111/j.1440-1746.2009.06160.x

Selenium's molecular mechanism for cancer chemoprevention remains unknown. We aimed to study the gene expression of nuclear factor-kappaB (NF-kappaB), tumor growth factor-alpha (TGF-alpha) and cyclin D1 and the effects of sodium selenite using preventive and therapeutic approaches in chemically-induced hepatocarcinogenesis in rats.

Matched MeSH terms: Cell Transformation, Neoplastic/chemically induced; Cell Transformation, Neoplastic/drug effects*; Cell Transformation, Neoplastic/metabolism; Cell Transformation, Neoplastic/pathology
Fulltext Prognostic Implications of DNA Repair, Ploidy and Telomerase in the Malignant Transformation Risk Assessment of Leukoplakia

Thomas G, Tr S, George S P, Somanathan T, Sarojam S, Krishnankutti N, et al.

Asian Pac J Cancer Prev, 2020 Feb 01;21(2):309-316.
PMID: 32102504 DOI: 10.31557/APJCP.2020.21.2.309

BACKGROUND: Although leukoplakia shows a higher risk for malignant transformation to oral cancer, currently there are no clinically relevant biomarker which can predict the potentially high risk leukoplakia. This study aimed to investigate the genetic alterations such as DNA ploidy, telomerase expression and DNA repair capacity as predictive markers of malignant transformation risk of leukoplakia.
METHODS: The study was initiated in September 2005 and patients were followed up to March 2014. Two hundred patients with oral leukoplakia, 100 patients with oral cancer and 100 healthy, age and sex matched adults with normal oral mucosa as controls were recruited. The DNA ploidy content was measured by high resolution flow cytometry, level of telomerase expression was identified by TRAP assay and intrinsic DNA repair capacity was measured by mutagen induced chromosome sensitivity assay of cultured peripheral blood lymphocytes. The Chi-square test or Fisher's Exact test was used for comparison of categorical variables between biomarkers. A p value less than or equal to 0.05 was considered as statistically significant. Analysis was performed with SPSS software version 16. Logistic regression was used to find the association between the dependent and three independent variables.
RESULTS: There was significant difference in the distribution of ploidy status, telomerase activity and DNA repair capacity among control, leukoplakia and oral cancer group (p<0.001). When the molecular markers were compared with histological grading of leukoplakia, both DNA ploidy analysis and telomerase activity showed statistical significance (p<0.001). Both aneuploidy and telomerase positivity was found to coincide with high-risk sites of leukoplakia and were statistically significant (p.

Matched MeSH terms: Cell Transformation, Neoplastic/genetics; Cell Transformation, Neoplastic/pathology*
Fulltext Malignant myeloid transformation in a child with severe congenital neutropenia (Kostmann's syndrome)

Chong LA, Josephine P, Ariffin H

Med J Malaysia, 2006 Jun;61(2):236-8.
PMID: 16898320 MyJurnal

We report a case of a child with severe congenital neutropenia (Kostmann's syndrome) who was treated with daily prophylactic subcutaneous granulocyte colony-stimulating factor (G-CSF) from the age of eight to sixteen years before being discontinued for poor haematological and clinical response. She did not have a HLA-matched sibling to enable bone marrow transplantation. She subsequently developed acute megakaryoblastic leukemia at the age of 17 years and succumbed during induction chemotherapy. The role of G-CSF in the pathogenesis of her malignant transformation to AML is complicated as this disorder has a propensity for myelodysplasia or AML as part of its natural history.

Matched MeSH terms: Cell Transformation, Neoplastic/pathology*
Areca nut: a review

Arjungi KN

Arzneimittelforschung, 1976;26(5):951-6.
PMID: 786304

Areca cattechu Linn is commonly known as areca nut or betel nut. It is a very widely cultivated plant in eastern countries like India, Bangladesh, Ceylon, Malaya, the Philippines and Japan. The importance of this nut is due to its use for chewing purposes. It had an important place as a pharmaceutical in Ayurveda--the ancient Indian system of medicine--also in the Chinese medicinal practices. The pharmaceutical importance of areca nut is due to the presence of an alkaloid, arecoline. Synthetic arecoline hydrobromide is also shown to possess numerous pharmacological properties. Chewing of "betel quid" or areca nut is a typical oriental habit. Betel quid comprises betel leaf, areca nut, catechu, lime and sometimes also tobacco. It is shown that there exists a correlationship between betel quid or areca nut chewing habit and oral cancer. A number of investigators have been able to produce cellular changes such as leukoplakia by application of betel quid or areca nut extract to the buccal mucosa of different animal.

Matched MeSH terms: Cell Transformation, Neoplastic
Effect of cacao liquor extract on tumor marker enzymes during chemical hepatocarcinogenesis in rats

Amin I, Koh BK, Asmah R

J Med Food, 2004;7(1):7-12.
PMID: 15117546

This study investigated the effect of cacao liquor extract (CLE) on tumor marker enzymes--alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), glutathione-S-transferase (GST), and glutathione reductase (GR) activities--in plasma and/or liver of hepatocarcinogenic rats, which were induced with diethylnitrosamine and 2-acetylaminofluorene. Twenty-nine male Sprague-Dawley rats (weighing 150-330 g) were divided into four groups (n = 6-8): normal control group (N), normal group + CLE (NE), cancer group (C), and cancer group + CLE (CE). Analysis of variance showed significant differences (P

Matched MeSH terms: Cell Transformation, Neoplastic/drug effects
Fulltext Stearoyl CoA Desaturase Is Essential for Regulation of Endoplasmic Reticulum Homeostasis and Tumor Growth in Glioblastoma Cancer Stem Cells

Pinkham K, Park DJ, Hashemiaghdam A, Kirov AB, Adam I, Rosiak K, et al.

Stem Cell Reports, 2019 04 09;12(4):712-727.
PMID: 30930246 DOI: 10.1016/j.stemcr.2019.02.012

Inherent plasticity and various survival cues allow glioblastoma stem-like cells (GSCs) to survive and proliferate under intrinsic and extrinsic stress conditions. Here, we report that GSCs depend on the adaptive activation of ER stress and subsequent activation of lipogenesis and particularly stearoyl CoA desaturase (SCD1), which promotes ER homeostasis, cytoprotection, and tumor initiation. Pharmacological targeting of SCD1 is particularly toxic due to the accumulation of saturated fatty acids, which exacerbates ER stress, triggers apoptosis, impairs RAD51-mediated DNA repair, and achieves a remarkable therapeutic outcome with 25%-100% cure rate in xenograft mouse models. Mechanistically, divergent cell fates under varying levels of ER stress are primarily controlled by the ER sensor IRE1, which either promotes SCD1 transcriptional activation or converts to apoptotic signaling when SCD1 activity is impaired. Taken together, the dependence of GSCs on fatty acid desaturation presents an exploitable vulnerability to target glioblastoma.

Matched MeSH terms: Cell Transformation, Neoplastic/genetics; Cell Transformation, Neoplastic/metabolism
Fulltext Analysis of octamer-binding transcription factor-4 expression in oral leukoplakia

Tegginamani AS, Shivakumar VH, Kallarakkal TG, Ismail SM, Abraham MT, Bin Zamzuri AT

J Oral Maxillofac Pathol, 2020 09 09;24(2):400.
PMID: 33456258 DOI: 10.4103/jomfp.JOMFP_272_19

Background: Oral potentially malignant disorders have a risk for malignant transformation but are difficult to reliably identify and predict which patients are at the risk for malignant transformation. OCT4 has been hypothesized to play a key oncogenic driver in a variety of solid tumors. A deeper understanding of the aberrant molecular pathways which lead to carcinogenesis needs to be identified by the potential markers.
Aims: To assess the OCT4 stemness factor in oral leukoplakia for its potential risk to malignant transformation.
Settings and Design: 20 cases of oral leukoplakia were obtained from archives at Oral Cancer Research & Coordinating center (OCRCC) Malaysia Subjects and Methods: 20 cases of oral leukoplakia were assessed by OCT4 immunohistochemically. Oral squamous cell carcinoma was used as a control.
Result: no expression of OCT 4 was observed in any cases of oral leukoplakia.
Conclusion: The molecular mechanisms of Oct4 regulation and in particular of its switch on and off in tissues depends upon its microenvironment, which makes it challenging in fundamental and applied research fields of regenerative medicine and cancer therapy. It's better that patients should undergo multiple biopsies for the early detection of malignant transformation with close follow-up during the first two to three years, a large amount of work remains to be done with multi-marker panel investigation, as cure rates have remained constant over three decades.

Matched MeSH terms: Cell Transformation, Neoplastic
Tissue microarray immunohistochemical profiles of p53 and pRB in hepatocellular carcinoma and hepatoblastoma

Azlin AH, Looi LM, Cheah PL

Asian Pac J Cancer Prev, 2014;15(9):3959-63.
PMID: 24935581

The tumour suppressor genes, p53 and pRb, are known to play important roles in neoplastic transformation. While molecular routes to the uncontrolled growth of hepatocytes, leading to primary liver cancer have generated considerable interest, the roles of p53 and pRb mutations in hepatocellular carcinoma (HCC) and hepatoblastoma (HB) remain to be clarified. We examined the immunohistochemical expression of p53 and pRb gene products in 26 HCC and 9 HB, sampled into tissue microarray blocks. 10 (38%) of 26 HCC showed > 10% tumour nuclear staining for p53 protein, 3 of these also being HbsAg positive. Conversely, none of 9 HB expressed nuclear p53 immunopositivity. Some 24 (92%) HCC and 8 (89%) HB showed loss of pRb nuclear expression. Two of the 26 HCC and one of the 9 HB showed >10% tumour nuclear staining for pRb protein. Our results suggest that p53 does not have an important role in the development of HB but may contribute in HCC. There is also loss of pRb expression in the majority of HCC and HB, supporting loss of pRb gene function in the hepatocarcinogenesis pathway. However, a comparison of the staining profiles of p53 and pRb proteins in HCC and HB did not reveal a consistent pattern to differentiate between the two types of tumours immunohistochemically. Hence the use of p53 and pRB protein expression has no contribution in the situation where there is a diagnostic difficulty in deciding between HCC and HB.

Matched MeSH terms: Cell Transformation, Neoplastic/genetics
Fulltext Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Lee JY, Bhandare RR, Boddu SHS, Shaik AB, Saktivel LP, Gupta G, et al.

Biomed Pharmacother, 2024 Apr;173:116275.
PMID: 38394846 DOI: 10.1016/j.biopha.2024.116275

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Matched MeSH terms: Cell Transformation, Neoplastic/genetics
Novel MDM2 splice variants identified from oral squamous cell carcinoma

Sam KK, Gan CP, Yee PS, Chong CE, Lim KP, Karen-Ng LP, et al.

Oral Oncol, 2012 Nov;48(11):1128-35.
PMID: 22705356 DOI: 10.1016/j.oraloncology.2012.05.016

The presence of a variety of MDM2 splice variants has been reported in a range of different tumor types and is associated with poor patient prognosis. Furthermore, several MDM2 variants have been shown to have oncogenic properties. Despite this, MDM2 splice variants have not been comprehensively characterized in oral squamous cell carcinoma (OSCC).

Matched MeSH terms: Cell Transformation, Neoplastic/genetics
Human telomerase reverse transcriptase expression in oral carcinogenesis--a preliminary report

Kumar SK, Zain RB, Ismail SM, Cheong SC

J Exp Clin Cancer Res, 2005 Dec;24(4):639-46.
PMID: 16471328

Human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase, is strongly associated with telomerase activity implicated in cellular immortalization and tumorigenesis. In situ detection of hTERT will aid in determining the localization of telomerase positive cells. The aim of this study was to detect hTERT protein expression in multistep oral carcinogenesis using paraffin embedded tissue samples, and to study the relationship of hTERT expression with different histological stages in oral carcinogenesis. Normal (n = 4), hyperplastic (n = 4), dysplastic (n = 4) and neoplastic (n = 10) oral epithelia representing different histological stages in oral carcinogenesis were included in the study. hTERT protein detection was done by immunohistochemistry (IHC) technique. Nuclear staining intensities were noted and the hTERT-labelling index was determined. Dysplastic and neoplastic oral epithelia showed an increased percentage of hTERT positive cells (Grade 4: > 50% positive staining nuclei) with intense staining in the basal, parabasal and superficial layers of the epithelia, unlike normal oral mucosa which showed intense staining only in the basal and parabasal cell layers, which are the normal proliferative progenitor compartments. hTERT protein expression was elevated with the corresponding advancement of the histological stages of oral carcinogenesis, from normal to hyperplasia to dysplasia to carcinoma. There seems to be an upregulation of hTERT protein expression during the progression of oral cancer, therefore, this may indicate the feasibility of IHC detection of hTERT protein in oral carcinogenesis as a potential diagnostic or prognostic marker.

Matched MeSH terms: Cell Transformation, Neoplastic/metabolism*; Cell Transformation, Neoplastic/pathology
HPV infection and the alterations of the pRB pathway in oral carcinogenesis

Lim KP, Hamid S, Lau SH, Teo SH, Cheong SC

Oncol Rep, 2007 Jun;17(6):1321-6.
PMID: 17487385 DOI: 10.3892/or.17.6.1321

Inactivation of the retinoblastoma (pRB) pathway is a common event in oral squamous cell carcinoma particularly through the aberrant expression of the components within this pathway. This study examines the alterations of molecules within the pRB pathway by looking at the presence of homozygous deletions in p16(INK4A) and the expression patterns of pRB, cyclin D1 and CDK4, as well as the presence of human papillomavirus (HPV) in our samples. In our study, 5/20 samples demonstrated deletions of p16(INK4A) exon 1alpha. pRB overexpression was found in 20/20 samples, the expression was mainly observed in all layers of the epithelia, particularly in the basal layer where cells are actively dividing and aberrant pRB expression was found in 12/20 samples. Cyclin D1 and CDK4 overexpression was detected in 6/20 and 2/20 samples respectively in comparison to hyperplasias where both proteins were either not expressed or expressed at minimal levels (<10%). Strikingly, HPV was found to be present in all of our samples, suggesting that HPV plays a significant role in driving oral carcinogenesis. Notably, 17/20 of our samples showed more than one alteration in the pRB pathway, however, we did not find any significant relationship between the presence of HPV, homozygous deletion of p16(INK4A) and overexpression of pRB, cyclin D1 and CDK4. Collectively, this data demonstrates that alterations in the pRB pathway are a common event and involve the aberration of more than one molecule within the pathway. Furthermore, the involvement of HPV in all our samples suggests that HPV infection may play an important role in oral carcinogenesis.

Matched MeSH terms: Cell Transformation, Neoplastic/genetics; Cell Transformation, Neoplastic/metabolism*
Myelodysplastic syndrome transformed into Acute Lymphoblastic Leukaemia (FAB:L3)

Zainina S, Cheong SK

Clin Lab Haematol, 2006 Aug;28(4):282-3.
PMID: 16898972

Myelodysplastic syndrome (MDS) is recognized as a preleukaemic disorder with a variable risk of transformation to acute myeloid leukaemia. Usually the blast cells in leukaemia are transformed after MDS displays a myeloid phenotype. Even though lymphoid progression had been reported previously, most displayed myeloid-lymphoid hybrid or early B phenotype. We report a case of an elderly man who had MDS transformed into Acute Lymphoblastic Leukaemia (ALL:L3) which is a rare lymphoid transformation.

Matched MeSH terms: Cell Transformation, Neoplastic/pathology*
The influence of folate and methionine on intestinal tumour development in the Apc(Min/+) mouse model

Teh AH, Symonds E, Bull C, Clifton P, Fenech M

Mutat Res Rev Mutat Res, 2012 05 22;751(1):64-75.
PMID: 22627043 DOI: 10.1016/j.mrrev.2012.05.001

Folate and methionine are critical for one-carbon metabolism impacting DNA synthesis, repair, and methylation processes, as well as polyamine synthesis. These micronutrients have been implicated in colorectal cancer risk. There are, however, inconsistencies within the literature, with some studies showing restriction to have tumour-inhibitory effects, whereas others suggest excess to have adverse outcomes. We conducted a review of the published data to examine the accumulated evidence for involvement of dietary folate and/or methionine restriction or excess in intestinal tumour development in the Apc(Min/+) mouse model, which is genetically prone to develop such cancers. Thirteen publications were selected for evaluation based on the following inclusion criteria: (i) use of Apc(Min/+) mouse model; (ii) interventions using dietary folate and/or methionine; and (iii) primary outcome measures focused on intestinal tumour development. We found that nutritional modulation of folate and methionine was shown to have different effects on intestinal cancer in the Apc(Min/+) mouse, depending on the dosage, duration and timing of intervention, and interaction of the Apc(Min/+) genotype with other genetic factors affecting folate and DNA methylation metabolism. Although some studies showed that folate deficiency before tumorigenesis tended to increase risk of tumour formation, there are inconsistencies regarding whether excess folate post-weaning or after tumour initiation increases intestinal tumour burden. Altogether, the pooled data do not appear to indicate a difference in effect on intestinal tumour incidence between post-weaning diets that are folate deficient or folate adequate. The Apc(Min/+) mouse is a useful model for assessment of the impact of dietary folate on intestinal tumour development, but further research is required to understand the reasons for these inconsistencies amongst studies based on likely mechanisms, including modulation of nucleotide synthesis, DNA methylation, and chromosomal instability, which may affect the rate of cellular division and its control.

Matched MeSH terms: Cell Transformation, Neoplastic

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