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Modulation of cell growth and PPARgamma expression in human colorectal cancer cell lines by ciglitazone

Yaacob NS, Darus HM, Norazmi MN

Exp. Toxicol. Pathol., 2008 Sep;60(6):505-12.
PMID: 18579355 DOI: 10.1016/j.etp.2008.05.006

Studies have shown that ligand activation of peroxisome proliferator-activated receptor gamma (PPARgamma) can induce differentiation and inhibit proliferation of several cancer cells. The present study was performed to investigate the effects of the PPARgamma ligand, ciglitazone, and the involvement of PPARgamma in modulating the growth of human colorectal cancer cells. Lactate dehydrogenase release assay showed that ciglitazone potently inhibited HT-29 (well-differentiated) and COLO-205 (poorly differentiated) colorectal adenocarcinoma cell growth. Measurement of apoptosis by flow cytometry using a fluorescein-conjugated monoclonal antibody against cytokeratin 18 revealed a high induction of apoptosis by ciglitazone in a time-dependent fashion. The expression of PPARgamma1 but not PPARgamma2 mRNA was significantly downregulated as measured by real-time quantitative PCR, and the PPARgamma protein levels were decreased as determined by Western blot analysis. We conclude that ciglitazone treatment suppressed colon cancer cell growth via induction of apoptosis. However, the anticancer effects of ciglitazone may not depend solely on PPARgamma activation.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/drug effects*
p16 gene expression in basal cell carcinoma

Eshkoor SA, Ismail P, Rahman SA, Oshkour SA

Arch Med Res, 2008 Oct;39(7):668-73.
PMID: 18760195 DOI: 10.1016/j.arcmed.2008.06.003

Basal cell carcinoma (BCC) develops predominantly in sun-exposed skin in fair-skinned individuals prone to sunburn. BCC typically occurs in adults. High exposure to ultraviolet (UV) radiation increases rate of developing BCC, a slowly growing tumor that occurs in hair-growing squamous epithelium and rarely metastasizes. In genetic studies, BCC patients have cell-cycle abnormalities of different parts of the signaling pathway. Retinoblastoma regulatory pathway is important in cell cycle arrest. In this pathway, p16INK4a, an inhibitor of Rb pathway, binds to CDK4 and CDK6 competitively with cyclin D1 to prevent phosphorylation of tumor suppressor pRB gene. Alteration of this pathway contributes to development of human cancers and also is effective in skin cancers. In this study, we analyzed mRNA expression using in situ RT-PCR and the role of immunohistochemical expression of p16INK4a in BCC.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
C-erbB-2 onco-protein expression in breast cancer: relationship to tumour characteristics and short-term survival in Universiti Kebansaan Malaysia Medical Centre

Sharifah NA, Lee BR, Clarence-Ko CH, Tan GC, Shiran MS, Naqiyah I, et al.

Asian Pac J Cancer Prev, 2008 Oct-Dec;9(4):663-70.
PMID: 19271345

Breast cancer is the commonest cancer affecting females in Malaysia, contributing 31% of all newly diagnosed cases amongst Malaysian women. The present retrospective cohort study evaluated the relationship between cerbB- 2 onco-protein overexpression with various tumour characteristics and survival rate of breast cancer patients treated at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC) between 1996-2000. CerbB- 2 oncoprotein overexpression was determined by immunohistochemistry (IHC) and tumors showing 2+ positivity were verified by Fluorescence In Situ Hybridization (FISH). One hundred and seventy two patients were eligible for the study with a short-term follow-up (median) of 5.1 years. C-erbB-2 oncoprotein overexpression correlated with lymph node positivity, oestrogen receptor (ER) and progesterone receptor (PR) negativity. Univariate analyses showed shorter disease free survival (DFS) and overall survival (OS) in patients with cerbB- 2 oncoprotein overexpression, Malay ethnicity, higher tumour grade, lymph node positivity, ER and PR negativity. In a subgroup of patients with c-erbB-2 oncoprotein overexpression, a shorter OS was observed in those with lymph node positivity, ER and PR negativity. In multivariate prognostic analysis, lymph node status, ER status and tumour grading were the strongest independent prognostic factors for both OS and DFS. However, c-erbB-2 status was not a significantly independent prognostic factor, even in subsets with lymph node positive or negative group. C-erbB-2 oncoprotein overexpression correlated well with lymph node status, ER and PR. Shorter OS and DFS were significantly observed in patients with c-erbB-2 oncoprotein overexpression. Lymph node status, ER status and tumour grading were the only three independent prognostic factors for OS and DFS in this study. Although c-erbB-2 expression is obviously important from a biological standpoint, multivariate analysis showed that it is not an independent prognostic indicator in breast carcinoma in the local population.

Matched MeSH terms: Gene Expression Regulation, Neoplastic*
Fulltext E-cadherin expression correlates with histologic type but not tumour grade in invasive breast cancer

Nurismah MI, Noriah O, Suryati MY, Sharifah NA

Asian Pac J Cancer Prev, 2008 Oct-Dec;9(4):699-702.
PMID: 19256762

The traditional classification of infiltrating breast carcinomas into ductal and lobular can be diagnostically challenging in a small proportion of cases with equivocal histological features and in in-situ lesions with overlapping features. Distinguishing between the infiltrating ductal (IDC) and lobular (ILC) carcinomas is clinically important because of the different pattern of systemic metastases and prognostic evaluation. E-cadherin is a potentially useful immunohistochemical marker which may serve to differentiate between the two tumour types. We therefore studied E-cadherin expression in 32 cases of breast carcinomas comprising 16 IDCs and 16 ILCs. The correlation between E-cadherin expression and the histological grade of IDCs was also analysed. Our results showed complete loss of E-cadherin expression in all ILCs, while the IDCs consistently showed variable E-cadherin positivity. No significant correlation was found between E- cadherin expression and the histological grade of IDCs. We conclude from this study that E-cadherin is a useful marker to differentiate between IDC and ILC of the breast. A larger study of IDCs is now needed to further evaluate the correlation between E-cadherin and tumour grade to estimate its prognostic potential.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
Immunohistochemical determination of the P15 protein expression in cutaneous squamous cell carcinoma

Moad AI, Lan TM, Kaur G, Hashim H, Mabruk MJ

J Cutan Pathol, 2009 Feb;36(2):183-9.
PMID: 18564286 DOI: 10.1111/j.1600-0560.2008.00989.x

The tumor suppressor gene p15(INK4b) is a cyclin-dependent kinase inhibitor, in which its inactivation has been determined in primary tumors and in several tumor-derived cell lines. The precise role of p15(INK4b) protein expression in cutaneous squamous cell carcinoma (SCC) is currently not known. In a previous study, we have shown the frequent occurrence of allelic imbalance/loss of heterozygosity in cutaneous SCC using two microsatellite markers flanking the p15(INK4b) gene. This study is a continuation of our previous study and aims to determine the possible role of p15(INK4b) protein expression in the genesis of cutaneous SCC. P15(INK4b) protein expression was determined using immunohistochemical approach in 107 cases of cutaneous SCC tissue arrays and 19 cases of normal human skin tissues. The expression of p15(INK4b) was significantly reduced in the cutaneous SCC cases as compared with normal human skin (p = 0.017 and p < 0.05). However, there were no significant relationship between clinicopathologic variables of the patients (age, sex and tumor grade) and p15(INK4b) protein expression. The absence of p15(INK4b) expression in the majority of tissue microarray cores of cutaneous SCC indicated that p15(INK4b) could possibly be involved in the pathogenesis of cutaneous SCC.

Matched MeSH terms: Gene Expression Regulation, Neoplastic*
Gene expression in human oral squamous cell carcinoma is influenced by risk factor exposure

Cheong SC, Chandramouli GV, Saleh A, Zain RB, Lau SH, Sivakumaren S, et al.

Oral Oncol, 2009 Aug;45(8):712-9.
PMID: 19147396 DOI: 10.1016/j.oraloncology.2008.11.002

Oral squamous cell carcinoma (OSCC) is a world health problem and is associated with exposure to different risk factors. In the west, smoking and alcohol consumption are considered to be the main risk factors whilst in India and southeast Asia, betel quid (BQ) chewing is predominant. In this study, we compared the gene expression patterns of oral cancers associated with BQ chewing to those caused by smoking using Affymetrix microarrays. We found that 281 genes were differentially expressed between OSCC and normal oral mucosa regardless of aetiological factors including MMP1, PLAU, MAGE-D4, GNA12, IFITM3 and NMU. Further, we identified 168 genes that were differentially expressed between the BQ and smoking groups including CXCL-9, TMPRSS2, CA12 and RNF24. The expression of these genes was validated using qPCR using independent tissue samples. The results demonstrate that whilst common genes/pathways contribute to the development of oral cancer, there are also other gene expression changes that are specific to certain risk factors. The findings suggest that different carcinogens activate or inhibit specific pathways during cancer development and progression. These unique gene expression profiles should be taken into consideration when developing biomarkers for future use in prognostic or therapeutic applications.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/physiology*
Fulltext PI3K/Akt activity has variable cell-specific effects on expression of HIF target genes, CA9 and VEGF, in human cancer cell lines

Shafee N, Kaluz S, Ru N, Stanbridge EJ

Cancer Lett, 2009 Sep 8;282(1):109-15.
PMID: 19342157 DOI: 10.1016/j.canlet.2009.03.004

The phosphatidylinositol 3-kinase/Akt (PI3K) pathway regulates hypoxia-inducible factor (HIF) activity. Higher expression of HIF-1alpha and carbonic anhydrase IX (CAIX), a hypoxia-inducible gene, in HT10806TG fibrosarcoma cells (mutant N-ras allele), compared to derivative MCH603 cells (deleted mutant N-ras allele), correlated with increased PI3K activity. Constitutive activation of the PI3K pathway in MCH603/PI3K(act) cells increased HIF-1alpha but, surprisingly, decreased CAIX levels. The cell-type specific inhibitory effect on CAIX was confirmed at the transcriptional level whereas epigenetic modifications of CA9 were ruled out. In summary, our data do not substantiate the generalization that PI3K upregulation leads to increased HIF activity.

Matched MeSH terms: Gene Expression Regulation, Neoplastic*
Fulltext Molecular responses during chemotherapy in acute myeloid leukemias in predicting poor-response to standard chemotherapy

Maha A, Cheong SK, Leong CF, Seow HF

Malays J Pathol, 2009 Dec;31(2):81-91.
PMID: 20514850 MyJurnal

Signal transduction pathways are constitutively expressed in leukaemic cells resulting in aberrant survival of the cells. It is postulated that in cells of chemo-sensitive patients, chemotherapy induces apoptotic signals leading to cell death while survival signals are maintained in cells of chemo-resistant patients. There is very little information currently, on the expression of these mediators in patients immediately after chemotherapy initiation. We examined the expression pattern of proinflammatory cytokines, signaling molecules of the PI3K and MAPK pathways molecules and death receptor, DR5 on paired samples at diagnosis and during chemotherapy in acute myeloid leukaemia patients treated with cytosine arabinoside and daunorubicin. The results were correlated with remission status one month after chemotherapy. We found that in chemo-sensitive patients, chemotherapy significantly increased the percentage of cases expressing TNF-alpha (p = 0.025, n = 9) and IL-6 (p = 0.002, n = 11) compared to chemo-resistant cases. We also observed an increased percentage of chemo-sensitive cases expressing DR5 and phosphorylated p38, and Jnk. Thus, expression of TNF-alpha, IL-6, DR5, phospho-p38 and phospho-Jnk may regulate cell death in chemo-sensitive cases. In contrast, a significantly higher percentage of chemo-resistant cases expressed phospho-Bad (p = 0.027, n = 9). IL-beta and IL-18 were also found to be higher in chemo-resistant cases at diagnosis and during chemotherapy. Thus, expression of various cellular molecules in leukaemic blasts during chemotherapy may be useful in predicting treatment outcome. These cellular molecules may also be potential targets for alternative therapy.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/drug effects*
Regulation of low-density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A reductase gene expression by thymoquinone-rich fraction and thymoquinone in HepG2 cells

Al-Naqeep G, Ismail M, Allaudin Z

J Nutrigenet Nutrigenomics, 2009;2(4-5):163-72.
PMID: 19887822 DOI: 10.1159/000227264

BACKGROUND AND AIM: Nigella sativa and its active constituent thymoquinone (TQ) have been exploited for their various health benefits. This work was aimed to investigate the regulatory effects of TQ-rich fraction (TQRF) and commercial TQ on the low-density lipoprotein receptor (LDLR) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) genes in HepG2 cells.
METHODS AND RESULTS: TQRF was extracted from N. sativa seeds using supercritical fluid extraction. The regulatory effects of TQRF at 80 microg/ml and TQ at 2 microg/ml on LDLR and HMGCR gene expression were investigated in HepG2 cells using quantitative real-time PCR. The TQ content in TQRF was 2.77% (w/w) and was obtained at a temperature of 40 degrees C and a pressure of 600 bar. Treatment of cells with TQRF and TQ resulted in a 7- and 2-fold upregulation of LDLR mRNA level, respectively, compared with untreated cells. The mRNA level of HMGCR was downregulated by 71 and 12%, respectively, compared with untreated cells.
CONCLUSION: TQRF and TQ regulated genes involved in cholesterol metabolism by two mechanisms, the uptake of low-density lipoprotein cholesterol via the upregulation of the LDLR gene and inhibition of cholesterol synthesis via the suppression of the HMGCR gene.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
p53 and nasopharyngeal carcinoma: a Malaysian study

Hoe SL, Lee ES, Khoo AS, Peh SC

Pathology, 2009;41(6):561-5.
PMID: 19900105

AIMS: Nasopharyngeal carcinoma (NPC) is a common malignancy among men in Malaysia. To determine the role of p53 in NPC, we screened for p53 mutations and evaluated the protein expression levels in samples from local patients with NPC.
METHODS: Fifty-three formalin-fixed, paraffin-embedded nasopharyngeal carcinoma tissue blocks were chosen for this study. The presence of Epstein-Barr virus (EBV) was determined by in situ hybridisation using an EBER probe. p53 protein expression was detected using immunohistochemistry. Simultaneously, amplifications by PCR were performed for p53 exons 5 to 8, followed by mutation screening via single strand conformation polymorphism (SSCP). Sequencing of all the four exons was performed in five samples with mobility shift. To rule out false negative results by SSCP, 13 samples with p53 overexpression and five samples with low p53 expression were randomly selected and sequenced.
RESULTS: There was no mutation found in exons 5 to 8 in all the samples despite 46 (87%) of them having high p53 levels. EBV was detected in 51 (96%) out of 53 samples. There was no statistically significant association between p53 expression level and EBV presence.
CONCLUSIONS: High-intensity staining for p53 by immunohistochemistry was common in our series of NPC tissue samples but was not associated with 'hot spot' mutations of exons 5-8 of the gene. We did not find a significant relationship between the expression level of p53 and presence of EBV. Our study confirms that mutation of the DNA-binding domain of p53 is rare in NPC.

Matched MeSH terms: Gene Expression Regulation, Neoplastic*
Differential expression of a subset of ribosomal protein genes in cell lines derived from human nasopharyngeal epithelium

Sim EU, Ang CH, Ng CC, Lee CW, Narayanan K

J Hum Genet, 2010 Feb;55(2):118-20.
PMID: 19927161 DOI: 10.1038/jhg.2009.124

Extraribosomal functions of human ribosomal proteins (RPs) include the regulation of cellular growth and differentiation, and are inferred from studies that linked congenital disorders and cancer to the deregulated expression of RP genes. We have previously shown the upregulation and downregulation of RP genes in tumors of colorectal and nasopharyngeal carcinomas (NPCs), respectively. Herein, we show that a subset of RP genes for the large ribosomal subunit is differentially expressed among cell lines derived from the human nasopharyngeal epithelium. Three such genes (RPL27, RPL37a and RPL41) were found to be significantly downregulated in all cell lines derived from NPC tissues compared with a nonmalignant nasopharyngeal epithelial cell line. The expression of RPL37a and RPL41 genes in human nasopharyngeal tissues has not been reported previously. Our findings support earlier suspicions on the existence of NPC-associated RP genes, and indicate their importance in human nasopharyngeal organogenesis.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/genetics*
Apoptotic effects of Physalis minima L. chloroform extract in human breast carcinoma T-47D cells mediated by c-myc-, p53-, and caspase-3-dependent pathways

Ooi KL, Tengku Muhammad TS, Lim CH, Sulaiman SF

Integr Cancer Ther, 2010 Mar;9(1):73-83.
PMID: 20150224 DOI: 10.1177/1534735409356443

The chloroform extract of Physalis minima produced a significant growth inhibition against human T-47D breast carcinoma cells as compared with other extracts with an EC(50) value of 3.8 microg/mL. An analysis of cell death mechanisms indicated that the extract elicited an apoptotic cell death. mRNA expression analysis revealed the coregulation of apoptotic genes, that is, c-myc , p53, and caspase-3. The c-myc was significantly induced by the chloroform extract at the earlier phase of treatment, followed by p53 and caspase-3. Biochemical assay and ultrastructural observation displayed typical apoptotic features in the treated cells, including DNA fragmentation, blebbing and convolution of cell membrane, clumping and margination of chromatin, and production of membrane-bound apoptotic bodies. The presence of different stages of apoptotic cell death and phosphatidylserine externalization were further reconfirmed by annexin V and propidium iodide staining. Thus, the results from this study strongly suggest that the chloroform extract of P. minima induced apoptotic cell death via p53-, caspase-3-, and c-myc-dependent pathways.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/drug effects
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: Gene Expression Regulation, Neoplastic/drug effects
Fulltext Gene expression patterns distinguish breast carcinomas from normal breast tissues: the Malaysian context

Pau Ni IB, Zakaria Z, Muhammad R, Abdullah N, Ibrahim N, Aina Emran N, et al.

Pathol Res Pract, 2010 Apr 15;206(4):223-8.
PMID: 20097481 DOI: 10.1016/j.prp.2009.11.006

Genomic and transcriptomic alterations that affect cellular processes, such as cell proliferation, differentiation, apoptosis and invasion, commonly occur in breast oncogenesis. Epidemiological evidence has proven that the risk of breast cancer predisposition varies among different ethnicities. This study aims to identify the transcriptome changes that commonly occur during the transition of normal breast epithelium to carcinoma in three local ethnic groups (Malays, Chinese and Indians). The gene expression patterns of 43 breast carcinomas with 43 patient-matched normal breast tissues were investigated using Affymetrix U133A GeneChip (containing 22,283 probe sets targeting approximately 18,400 different transcripts) and analyzed with GeneSpring GX10. Our findings revealed a total of 33 significantly differentially expressed genes, which showed>2-fold change at a 99.9% confidence interval level (p<0.001). The significantly differentially expressed genes included CD24, CD36, CD9, TACSTD1, TACSTD2, HBB, LEP, LPL, AKR1C1, AKR1C2 and AKR1C3. Our results indicate that the vast majority of gene expression changes, from normal breast epithelial to carcinoma, found in our three major ethnic populations are similar to those in the Caucasian population. Further study of the differentially expressed genes identified in our present study is needed to search for potential breast tumor biomarkers. This will eventually help to improve the therapeutic and treatment strategies for breast cancer patients in the future.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
Transcriptional profiling of oral squamous cell carcinoma using formalin-fixed paraffin-embedded samples

Saleh A, Zain RB, Hussaini H, Ng F, Tanavde V, Hamid S, et al.

Oral Oncol, 2010 May;46(5):379-86.
PMID: 20371203 DOI: 10.1016/j.oraloncology.2010.02.022

Despite the advances in cancer treatment, the 5-year survival rate for oral cancer has not changed significantly for the past 40 years and still remains among the worst of all anatomic sites. Gene expression microarrays have been used successfully in the identification of genetic alterations in cancer development, however, these have hitherto been limited by the need for specimens with good quality intact RNA. Here, we demonstrated the use of formalin-fixed paraffin-embedded tissues in microarray experiments to identify genes differentially expressed between cancerous and normal oral tissues. Forty-three tissue samples were macrodissected and gene expression analyses were conducted using the Illumina DASL assay. We report RNA yield of 2.4 and 0.8 microg/mm(3) from tumour and normal tissues, respectively and this correlated directly with the tissue volume used for RNA extraction. Using unsupervised hierarchical clustering, distinct gene expression profiles for tumour and normal samples could be generated, and differentially expressed genes could be identified. The majority of these genes were involved in regulation of apoptosis and cell cycle, metastasis and cell adhesion including BCL2A1, BIRC5, MMP1, MMP9 and ITGB4. Representative genes were further validated in independent samples suggesting that these genes may be directly associated with oral cancer development. The ability to conduct microarrays on formalin-fixed paraffin-embedded specimens represents a significant advancement that could open up avenues for finding genes that could be used as prognostication and predictive tools for cancer.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
Notch4 overexpression in ameloblastoma correlates with the solid/multicystic phenotype

Siar CH, Nagatsuka H, Chuah KS, Rivera RS, Nakano K, Ng KH, et al.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2010 Aug;110(2):224-33.
PMID: 20659700 DOI: 10.1016/j.tripleo.2010.03.009

Notch signaling has been implicated in cell fate decisions during odontogenesis and tumorigenesis of some odontogenic neoplasms; however, its role in solid/multicystic (SA), unicystic (UA), and recurrent (RA) ameloblastoma remains unclear. The aim of this study was to determine Notch receptor and ligand expressions in these subtypes and to speculate on their significance.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
Differential expression of Notch receptors and their ligands in desmoplastic ameloblastoma

Siar CH, Nakano K, Han PP, Nagatsuka H, Ng KH, Kawakami T

J Oral Pathol Med, 2010 Aug 1;39(7):552-8.
PMID: 20337864 DOI: 10.1111/j.1600-0714.2009.00871.x

In mammals, the Notch gene family encodes four receptors (Notch1-4), and all of them are important for cell fate decisions. Notch signaling pathway plays an essential role in tooth development. The ameloblastoma, a benign odontogenic epithelial neoplasm, histologically recapitulates the enamel organ at bell stage. Notch has been detected in the plexiform and follicular ameloblastoma. Its activity in the desmoplastic ameloblastoma is unknown.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/genetics
Fulltext Potential chemoprevention of diethylnitrosamine-initiated and 2-acetylaminofluorene-promoted hepatocarcinogenesis by zerumbone from the rhizomes of the subtropical ginger (Zingiber zerumbet)

Taha MM, Abdul AB, Abdullah R, Ibrahim TA, Abdelwahab SI, Mohan S

Chem Biol Interact, 2010 Aug 05;186(3):295-305.
PMID: 20452335 DOI: 10.1016/j.cbi.2010.04.029

Zerumbone (ZER), a monosesquiterpene found in the subtropical ginger (Zingiber zerumbet Smith), possesses antiproliferative properties to several cancer cells lines, including the cervical, skin and colon cancers. In this study, the antitumourigenic effects of ZER were assessed in rats induced to develop liver cancer with a single intraperitoneal injection of diethylnitrosamine (DEN, 200 mg/kg) and dietary 2-acetylaminofluorene (AAF) (0.02%). The rats also received intraperitoneal ZER injections at 15, 30 or 60 mg/kg body wt. twice a week for 11 weeks, beginning week four post-DEN injection. The hepatocytes of positive control (DEN/AAF) rats were smaller with larger hyperchromatic nuclei than normal, showing cytoplasmic granulation and intracytoplasmic violaceous material, which were characteristics of hepatocarcinogenesis. Histopathological evaluations showed that ZER protects the rat liver from the carcinogenic effects of DEN and AAF. Serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (AP) and alpha-fetoprotein (AFP) were significantly lower (P<0.05) in ZER-treated than untreated rats with liver cancer. The liver malondialdehyde (MDA) concentrations significantly (P<0.05) increased in the untreated DEN/AAF rats indicating hepatic lipid peroxidation. There was also significant (P<0.05) reduction in the hepatic tissue glutathione (GSH) concentrations. The liver sections of untreated DEN/AAF rats also showed abundant proliferating cell nuclear antigen (PCNA), while in ZER-treated rats the expression of this antigen was significantly (P<0.05) lowered. By the TUNEL assay, there were significantly (P<0.05) higher numbers of apoptotic cells in DEN/AAF rats treated with ZER than those untreated. Zerumbone treatment had also increased Bax and decreased Bcl-2 protein expression in the livers of DEN/AAF rats, which suggested increased apoptosis. Even after 11 weeks of ZER treatment, there was no evidence of abnormality in the liver of normal rats. This study suggests that ZER reduces oxidative stress, inhibits proliferation, induces mitochondria-regulated apoptosis, thus minimising DEN/AAF-induced carcinogenesis in rat liver. Therefore, ZER has great potential in the treatment of liver cancers.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/drug effects
Fulltext Differential expression of galectin-3 in advancing thyroid cancer cells: a clue toward understanding tumour progression and metastasis

Htwe TT, Karim N, Wong J, Jahanfar S, Mansur MA

Singapore Med J, 2010 Nov;51(11):856-9.
PMID: 21140111

INTRODUCTION: Galectin-3 is a member of the beta-galactoside-binding protein family that plays an important role in cell-to-cell adhesion and in cell-to-matrix interaction. Cellular expression of galectin-3 is correlated with cancer aggressiveness and metastasis.
METHODS: We examined the differential expression of galectin-3 in a collection of 142 cases of thyroid lesions, including 108 cases of papillary thyroid carcinoma (PTC) and 34 cases of follicular carcinoma (FCA). An immunohistochemical method was applied and semiquantitative scoring was performed on the staining intensity of the positive tissue. Scoring was done on cells at the central portion of the tumour foci and on cells at the periphery that were adjacent to the neighbouring normal thyroid tissue matrix.
RESULTS: A significantly higher expression (p is 0.001) of galectin-3 was observed in the advancing peripheral thyroid cancer cells compared to the centrally located cells that were not in close contact with the neighbouring stromal tissue in cases with PTC compared to those with FCA.
CONCLUSION: This finding supported the role of galectin-3 in its cell-to-cell adhesion and cell-to-matrix interaction. Galectin-3 is a potential tumour marker for indicating local and distance metastasis, especially in cases with PTC.

Matched MeSH terms: Gene Expression Regulation, Neoplastic
Palm tocotrienols inhibit proliferation of murine mammary cancer cells and induce expression of interleukin-24 mRNA

Selvaduray KR, Radhakrishnan AK, Kutty MK, Nesaretnam K

J Interferon Cytokine Res, 2010 Dec;30(12):909-16.
PMID: 21121862 DOI: 10.1089/jir.2010.0021

Several mechanisms have been postulated for the anticancer effects of tocotrienols. In this study, for the first time, the anticancer effect of tocotrienols is linked to increased expression of interleukin-24 (IL-24) mRNA, a cytokine reported to have antitumor effects in many cancer models. Tocotrienol isomers (α-T3, γ-T3, and δ-T3) and tocotrienol-rich fraction (TRF) inhibited the growth of the 4T1 murine mammary cancer cells (P γ-T3 > TRF > α-T3 > α-T, which was similar to their antiproliferative effects. The IL-24 mRNA levels in tumor tissues of BALB/c mice supplemented with TRF increased 2-fold when compared with control mice. Increased levels of IL-24 have been associated with inhibition of tumor growth and angiogenesis. Treatment of 4T1 cells with TRF and δ-T3 significantly decreased IL-8 and vascular endothelial growth factor mRNA levels. Hence, we report that tocotrienols have potent antiangiogenic and antitumor effects that is associated with increased levels of IL-24 mRNA.

Matched MeSH terms: Gene Expression Regulation, Neoplastic/drug effects*

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