Syam Mohan

Potential chemoprevention of diethylnitrosamine-initiated and 2-acetylaminofluorene-promoted hepatocarcinogenesis by zerumbone from the rhizomes of the subtropical ginger (Zingiber zerumbet)

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.

Typhonium flagelliforme induces apoptosis in CEMss cells via activation of caspase-9, PARP cleavage and cytochrome c release: Its activation coupled with G0/G1 phase cell cycle arrest

ETHNOPHARMACOLOGICAL RELEVANCEnThe plant Typhonium flagelliforme (TF), commonly known as rodent tuber in Malaysia, is often used as traditional remedy for cancer, including leukemia.nnnAIM OF THE STUDYnWe had previously identified morphologically that the linoleic acid rich fraction (DCM/F7) from the tubers of this plant induces selective anti-proliferative effects and apoptosis in CEMss cells. In this present study, we subjected the same DCM/F7 fraction to cell based activity analyses in order to determine the possible mechanism of cell death in leukemic CEMss cells in vitro.nnnMATERIALS AND METHODSnExtraction of Typhonium flagelliforme tuber has done and fractionation has been done by vacuum liquid column chromatography. The anti-proliferative activity was assayed using MTT and the apoptosis detection was done by Annexin V and DNA laddering assay. Colorimetric caspase assay and immunoblot analysis were employed to detect the expression of protein associated with cell death. Cell cycle analysis was done using flow cytometry.nnnRESULTSnWe found that the cancer inhibitory effect of the DCM/F7 fraction in CEMss cells was 3 ± 0.08 μg/ml (IC(50)). An early apoptotic induction in CEMss cells was observed by Annexin V assay, which showed a clear dose-dependent DNA fragmentation being observed in gel electrophoresis at 10 and 20 μg/ml. The DCM/F7 fraction at 3 μg/ml significantly arrested CEMss cells at G0/G1 phase (p<0.05). A constant but increasing pattern-related Sub-G0/G1 index was observed between 12 and 72 h treatment. In relation to this, we further investigated the biochemical events leading to cell death and found that the DCM/F7 fraction increased the cellular levels of caspase-3 and -9 on treated cells. Our results indicated that cytochrome c from mitochondria into the cytosol increased gradually as the DCM/F7 concentration increases, which later lead to the subsequent cleavage of PARP in to 85kDa fragments. On the contrary, Bcl-2 protein was found to decrease concomitantly during treatment.nnnCONCLUSIONSnCollectively, results presented in this study demonstrated that the DCM/F7 fraction inhibited the proliferation of leukemia cells, leading to the programmed cell death, which was confirmed to be through the mitochondrial pathway.

Zerumbone induces apoptosis in T-acute lymphoblastic leukemia cells

Zerumbone (ZER) is a potential anticancer natural compound, isolated from Zingiber zerumbet Smith. In this investigation, the anticancer properties of ZER were evaluated on cancer cells of T-acute lymphoblastic leukemia, CEM-ss. The results showed that ZER has cytotoxic effect against CEM-ss cells with an IC(50) of 8.4 ± 1.9 μg/ml (coefficient of variation < 30%). Comparatively, 5-fluorouracil (positive control), imposed an inhibitory effect on CEM-ss cells with an IC(50) of 1.94 ± 0.06 μg/ml. Scanning electron microscopy (SEM) results revealed abnormalities such as membrane blebbing, holes and cytoplasmic extrusions, all of which are characteristics of apoptosis. In addition, ZER has increased the number of TUNEL-positive stain and the cellular level of caspase-3, the hallmarks of apoptosis, on treated CEM-ss cells. It could be concluded that, ZER was able to produce apoptosis on T-acute lymphoblastic leukemia, CEM-ss. The current findings suggest that ZER might be helpful for improving the usefulness of anticancer agents in the therapy of leukemia.

Typhonium flagelliforme inhibits the proliferation of murine leukemia WEHI-3 cells in vitro and induces apoptosis in vivo

Typhonium flagelliforme (TF) is a tropical plant, traditionally used by the ethnic population of Malaysia for the cure of various cancers. This plant had shown to induce antiproliferative effect as well as apoptosis in cancer cells. However, there is no available information to address that TF affects murine leukemia cells in vitro and in vivo. Here, we investigated in vitro and in vivo effects of TF on murine leukemia WEHI-3 cells. It was found that the growth of leukemia cells in vitro was inhibited by the various extracts of TF. Among these fractions, the dichloromethane (DCM) tuber extracts of TF showed the lowest IC(50) (24.0 ± 5.2 μg/ml) and had demonstrated apoptogenic effect when observed under fluorescent microscope. We investigated the in vivo effects of DCM tuber extracts of TF on murine leukemia cells, and the results showed that the counts of immature granulocytes and monocytes were significantly decreased in peripheral blood of BALB/c leukemia mice after the oral administration of DCM tuber extracts of TF for 28 days with three doses (200, 400 and 800 mg/kg). These results were confirmed by observing the spleen histopathology and morphology of enlarged spleen and liver in leukemia mice when compared with the control. Furthermore, the cell death mechanism in the spleen tissue of treated mice was found via apoptosis.

Regression of cervical intraepithelial neoplasia by zerumbone in female Balb/c mice prenatally exposed to diethylstilboestrol: involvement of mitochondria-regulated apoptosis.

BACKGROUNDnCervical cancer is the second most common cause of cancer death in women. We have demonstrated previously that zerumbone (ZER) has an anti-cancer effect towards human cervical cancer cells (HeLa).nnnMETHODSnAnti-cancer properties of ZER were investigated using female Balb/c mice exposed prenatally to diethylstilboestrol. Female offspring have been treated with ZER (4, 8 and 16 mg/kg), normal saline and cisplatin (10mg/kg; positive control). The anti-cancer properties of ZER were evaluated using histopathology, TdT-mediated dUTP nick end labeling (TUNEL) Assay and immunohistochemical staining of Bcl-2-associated X protein (Bax), a key protein in mitochondrial pathway of apoptosis. In addition, laser capture microdissection microscopy isolated RNA was amplified using reverse transcriptase polymerase chain reaction (RT-PCR) based on the specific primer of B-cell lymphoma 2 (Bcl-2).nnnRESULTSnTreatment with ZER resulted (P<0.05, chi(2) statistics) in the regression of cervical intraepithelial neoplasia (CIN) resembling cisplatin effect (10mg/kg). TUNEL micrographs showed the absence of apoptosis in cancerous tissues treated with normal saline compared to ZER and cisplatin where abundant apoptotic cells were noticed. A post hoc analysis showed a significant (P<0.01) difference in mean percentage of apoptosis between normal saline treatment (0%), ZER (15.7%) and cisplatin (21.7%). Immunohistochemical staining of Bax protein revealed that ZER modulates the expression of this apoptosis marker. Administration of ZER has also modulated the expression of Bcl-2 gene.nnnCONCLUSIONnThese findings showed that ZER induces apoptosis efficiently in cervical tissues from female Balb/c mice treated prenatally with diethylstilboestrol. This suggested that ZER, a plant-derived compound, could be introduced as a new chemo-preventive agent for CIN in future.

In vivo and In vitro Genotoxic Effects of Zerumbone.

Abstract Zerumbone (ZER) is derived from Zingiber zerumbet smith from the Zingiberaceae family. It has been shown to have anti-cancer and apoptosis-inducing properties against various human tumour cells. The aim of our study was to assess the genotoxic effects of ZER in cultured human peripheral blood lymphocytes, Chinese Hamster Ovary (CHO) cells and rat bone marrow polychromatic erythrocytes (PCEs) using micronucleus test (MN). All in vitro treatments were carried out in the absence of any exogenous metabolic activation system. Mitomycin C (MMC) was used as a positive control for in vitro treatments, while cisplatin was used as a positive micronucleus inducer in rat bone marrow PCEs. ZER at high concentrations induced an apparent signifi cant increase in the frequency of micronuclei in vivo (1000 mg/kg b.w) and in vitro (40 and 80 μM) compared to concurrent control values. Our in vivo and in vitro cytogenotoxicity studies suggest that high doses of ZER may be genotoxic and cytotoxic.

Dentatin Isolated from Clausena Excavata Induces Apoptosis in MCF-7, PC-3 and LNCaP Cells: an Evaluation by the Bioactivity Assay GuidedFractionation

UPM-MAKNA Cancer Research Laboratory, Institute of Bioscience, University Putra Malaysia, Serdang, Selangor, Malaysia; Department of Chemistry, Faculty of Science, University Putra Malaysia, Serdang, Selangor, Malaysia; Department of Veterinary Pathology and Microbiology, Faculty of Veterinary, University Putra Malaysia, Serdang, Selangor, Malaysia; Department of Microbiology, Faculty of Veterinary Science, University of Nyala, Nyala, Sudan; Department of Pharmacy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Medical Research Centre, Jazan University, P.O. Box 114 Jazan, Kingdom of Saudi Arabia; E-mails: arbabismailadam@yahoo.com; ismailupm2011@gmail.com