• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4807-4814
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• 2012

Purpose: The chemoresistance of human hepatocellular carcinoma (HCC) to cytotoxic drugs, especially intrinsic or acquired multidrug resistance (MDR), still remains a major challenge in the management of HCC. In the present study, possible mechanisms involved in MDR of HCC were identified using a 5-fluorouracil (5-FU)-resistant human HCC cell line. Methods: BEL-7402/5-FU cells were established through continuous culturing parental BEL-7402 cells, imitating the pattern of chemotherapy clinically. Growth curves and chemosensitivity to cytotoxic drugs were determined by MTT assay. Doubling times, colony formation and adherence rates were calculated after cell counting. Morphological alteration, karyotype morphology, and untrastructure were assessed under optical and electron microscopes. The distribution in the cell cycle and drug efflux pump activity were measured by flow cytometry. Furthermore, expression of potential genes involved in MDR of BEL-7402/5-FU cells were detected by immunocytochemistry. Results: Compared to its parental cells, BEL-7402/5-FU cells had a prolonged doubling time, a lower mitotic index, colony efficiency and adhesive ability, and a decreased drug efflux pump activity. The resistant cells tended to grow in clusters and apparent changes of ultrastructures occurred. BEL-7402/5-FU cells presented with an increased proportion in S and G2/M phases with a concomitant decrease in G0/G1 phase. The MDR phenotype of BEL-7402/5-FU might be partly attributed to increased drug efflux pump activity via multidrug resistance protein 1 (MRP1), overexpression of thymidylate synthase (TS), resistance to apoptosis by augmentation of the Bcl-xl/Bax ratio, and intracellular adhesion medicated by E-cadherin (E-cad). P-glycoprotein (P-gp) might play a limited role in the MDR of BEL-7402/5-FU. Conclusion: Increased activity or expression of MRP1, Bcl-xl, TS, and E-cad appear to be involved in the MDR mechanism of BEL-7402/5-FU.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2683-2688
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• 2016

A salt compound of a curcumin analogue, potassium pentagamavunon-0 (K PGV-0) has been synthesized to improve solubility of pentagamavunon-0 which has been proven to have anti-proliferative effects on several cancer cells. The purpose of this study was to investigate cytotoxic activity and metastasis inhibition by K PGV-0 alone and in combination with achemotherapeutic agent, doxorubicin (dox), in breast cancer cells. Based on MTT assay analysis, K PGV-0 showed cytotoxic activity in T47D and 4T1 cell lines with $IC_{50}$ values of $94.9{\mu}M$ and $49.0{\pm}0.2{\mu}M$, respectively. In general, K PGV-0+dox demonstrated synergistic effects and decreased cell viability up to 84.7% in T47D cells and 62.6% in 4T1 cells. Cell cycle modulation and apoptosis induction were examined by flow cytometry. K PGV-0 and K PGV-0+dox caused cell accumulation in G2/M phase and apoptosis induction. Regarding cancer metastasis, while K PGV-0 alone did not show any inhibition of 4T1 cell migration, K PGV-0+dox exerted inhibition. K PGV-0 and its combination with dox inhibited the activity of MMP-9 which has a pivotal role in extracellular matrix degradation. These results show that a combination of K PGV-0 and doxorubicin inhibits cancer cell growth through cell cycling, apoptosis induction, and inhibition of cell migration and MMP-9 activity. Therefore, K PGV-0 may have potential for development as a co-chemotherapeutic agent.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.615-618
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• 2016

Ethyl acetate extracts obtained from culture of endophytic fungi Aspergillus sp isolated from Piper crocatum Ruiz & Pav, have been shown to possess cytotoxic activity against T47D breast cancer cells. Investigations were here conducted to determine bioactive compounds responsible for the activity. Bioassay guided fractionation was employed to obtain active compounds. Structure elucidation was performed based on analysis of LC-MS, $^1H$-NMR, $^{13}C$-NMR, COSY, DEPT, HMQC, HMBC data. Cytotoxity assays were conducted in 96 well plates against T47D and Vero cell lines. Bioassay guided isolation and chemical investigation led to the isolation of pyrophen, a 4-methoxy-6-(1'-acetamido-2'-phenylethyl)-2H-pyran-2-one. Further analysis of its activity against T47D and Vero cells showed an ability to inhibit the growth of T47D cells with IC50 values of $9.2{\mu}g/mL$ but less cytotoxicity to Vero cells with an $IC_{50}$ of $109{\mu}g/mL$. This compound at a concentration of 400 ng/mL induced S-phase arrest in T47D cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6575-6580
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• 2014

This study aimed to evaluate the antimutagenic and anticarcinogenic activity of turmeric essential oil as well as to establish biochemical mechanisms of action. Antimutagenicity testing was accomplished using strains and known mutagens with and without microsomal activation. Anticarcinogenic activity was assessed by topical application of 7, 12 - dimethylbenz[a]anthracene (DMBA) as initiator and 1% croton oil as promoter for the induction of skin papillomas in mice. Inhibition of p450 enzymes by TEO was studied using various resorufins and aminopyrene as substrate. Turmeric essential oil (TEO) showed significant antimutagenic activity (p<0.001) against direct acting mutagens such as sodium azide ($NaN_3$), 4-nitro-O-phenylenediamine (NPD) and N-methyl-N-nitro N'nitrosoguanine (MNNG). TEO was found to have significant antimutagenic effect (>90%) against mutagen needing metabolic activation such as 2-acetamidoflourene (2-AAF). The study also revealed that TEO significantly inhibited (p<0.001) the mutagenicity induced by tobacco extract to Salmonella TA 102 strain. DMBA and croton oil induced papilloma development in mice was found to be delayed and prevented significantly by TEO application. Moreover TEO significantly (P<0.001) inhibited isoforms of cytochrome p450 (CYP1A1, CYP1A2, CYP2B1/2, CYP2A, CYP2B and CYP3A) enzymes in vitro, which are involved in the activation of carcinogens. Results indicated that TEO is antimutagenic and anticarcinogenic and inhibition of enzymes (p450) involved in the activation of carcinogen is one of its mechanisms of action.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2763-2769
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• 2015

Background: Cancer is an unnatural type of tissue growth in which the cells exhibit unrestrained division, leading to a progressive increase in the number of dividing cells. It is now the second largest cause of death in the world. The present study concerned antioxidant, anticancer and anticholinesterase activities and protocatechuic, catechin, caffeic acid, syringic acid, p-coumaric acid and o-coumaric concentrations in methanol extracts of flowers, fruits and seeds of Hypericum amblysepalum. Materials and Methods: Antioxidant properties including free radical scavenging activity and reducing power, and amounts of total phenolic compounds were evaluated using different tests. Protocatechuic, catechin, caffeic acid, syringic acid, p-coumaric acid and o-coumaric concentrations in extracts were determined by HPLC. Cytotoxic effects were determined using the MTT test with human cervix cancer (HeLa) and rat kidney epithelium cell (NRK-52E) lines. Acetyl and butyrylcholinesterase inhibitory activities were measured by by Ellman method. Results: Total phenolic content of H. amblysepalum seeds was found to be higher than in fruit and flower extracts. DPPH free radical scavenging activity of the obtained extracts gave satisfactory results versus butylated hydroxyanisole and butylated hydroxytoluene as controls. Reducing power activity was linearly proportional to the studied concentration range: $10-500{\mu}g/mL\;LC_{50}$ values for H. amblysepalum seeds were 11.7 and 2.86 respectively for HeLa and NRK-52E cell lines. Butyryl-cholinesterase inhibitory activity was $76.9{\pm}0.41$ for seed extract and higher than with other extracts. Conclusions: The present results suggested that H. amblysepalum could be a potential candidate anti-cancer drug for the treatment of human cervical cancer, and good source of natural antioxidants.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4129-4133
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• 2014

Background: The objective was to study the effect of Scutellaria baicalensis Georgi ethanol extracts (SBGE) on immune and anti-oxidant function in U14 tumor-bearing mice. Materials and Methods: U14 tumor-bearing mice were randomly divided into eight groups: a control group, a cyclophosphamide (CTX) group, three dose groups of SBGEI (high, medium, low), and three dose groups of SBGEII (high, medium, low). After two weeks, the thymus and spleen weight indices of mice bearing U14 cervical cancer were calculated. Enzyme linked immunosorbent assays (ELISA) was used to determine the levels of serum IL-2, TNF-${\alpha}$, IL-8, and PCNA. MDA activity and SOD activity in plasma were measured with detection kits. Results: In the SBGE groups, thymus weight and spleen weight indices of U14 tumor-bearing mice were significantly higher than in the control group or CTX group (p<0.05). Compared to control group, the levels of serum IL-2 and TNF-${\alpha}$ in U14 tumor-bearing mice increased significantly, whereas the contents of serum IL-8 and PCNA decreased (p<0.05). The activity of SOD increased with the growing dose of SBGE, while the activity of MDA decreased significantly in the highe-rdose groups of SBGE. Conclusions: These findings suggested that SBGE, especially at high dose, 1000 mg/kg, showed significant immune and anti-oxidant effects infU14 tumor-bearing mice, which might be the mechanisms of SBGE inhibition of tumor growth.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.309-314
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• 2013

Aim: Brain tumors almost universally have fatal outcomes; new therapeutics are desperately needed and will only come from improved understandins of glioma biology. Methods: Exosomes are endosomally derived 30~100 nm membranous vesicles released from many cell types. Examples from GL26 cells were here purified using density gradient ultracentrifugation and monitored for effects on GL26 tumor growth in C57BL/6j mice (H-2b). Lactate dehydrogenase release assays were used to detect the cytotoxic activity of CD8+T and NK cells. Percentages of immune cells producing intracellular cytokines were analyzed by FACS. Results: In this study, exosomes from murine-derived GL26 cells significantly promoted in vivo tumor growth in GL26-bearing B6 mice. Then we further analyzed the effects of the GL26 cells-derived exosomes on immune cells including CD8+T, CD4+T and NK cells. Inhibition of CD8+T cell cytotoxic activity was demonstrated by CD8+T cell depletion assays in vivo and LDH release assays in vitro. The treatment of mice with exosomes also led to a reduction in the percentages of CD8+T cells in splenocytes as determined by FACS analysis. Key features of CD8+T cell activity were inhibited, including release of IFN-gamma and granzyme B. There were no effects of exosomes on CD4+T cells and NK cells. Conclusion: Based on our data, for the first time we demonstrated that exosomes from murine derived GL26 cells promote the tumor growth by inhibition of CD8+T cells in vivo and thus may be a potential therapeutic target.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6279-6284
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• 2015

Opisthorchis viverrini (OV)-induced cholangiocarcinoma (CCA) is an important cancer in the Great Mekong region, particularly in Thailand. Limitations of treatment options and the lack of an effective diagnostic tool for early detection of CCA are major concerns for the control of this type of cancer. The aim of the study was to investigate anti-CCA activity of the ethanolic extract of Atractylodes lancea (Thunb.) DC., and the applicability of positron emission tomography-computed tomography (PET-CT) as a tool for detection and monitoring the progression of CCA in Opisthorchis viverrini (OV)/dimethylnitrosamine (DMN)-induced CCA hamsters. Male Syrian hamsters were used for toxicity tests and anti-CCA activity evaluation. Development of CCA was induced by initial feeding of 50 metacercariae of OV, followed by drinking water containing 12.5 ppm of DMN in hamsters. The ethanolic extract of A. lancea (Thunb.) DC. was administered orally for 30 days. PET-CT was performed every 4 weeks after initiation of CCA using 18F-fluorodeoxyglucose ($^{18}F-FDG$). Results from the present study suggest that the ethanolic extract of A. lancea (Thunb.) DC. rhizome exhibited promising anti-CCA activity and safety profile in the OV/DMN-induced hamster model. To successfully apply PET-CT as a tool for early detection of tumor development and progression, modification of radiolabeling approach is required to improve its specificity for CCA cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6073-6076
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• 2012

Discovery of anticancer drugs that kill or disable tumor cells in the presence of normal cells without undue toxicity is a potential challenge for therapeutic care. Several papers in the literature have emphasized the potential implications of marine products such as seaweeds which exhibit antitumor activity. Study attempts to screen the antitumor effect of Sargassum sp, against chosen cell lines such as MCF-7 (Breast cancer) and Hep-2 (Liver Cancer). Ethanol extract of Sargassum sp. was concentrated using a Soxhlet apparatus and dissolved in DMSO. In vitro cytotoxic activity of Sargassum sp at various concentrations ($100{\mu}g/ml-300{\mu}g/ml$) screened for antitumor effect against the chosen cell lines using MTT assay (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a yellow tetrazole). The study documented that the percentage of cell viability has been reduced with increased concentration, as evidenced by cell death. Sargassum sp extract shows potential cytotoxic activity ($P{\leq}0.05$) with $IC_{50}$ of $200{\mu}g/ml$ and $250{\mu}g/ml$ against Hep-2 and MCF-7 cell lines respectively. The ethanol fraction of Sargassum sp induced cell shrinkage, cell membrane blebbing and formation of apoptotic bodies with evidence of bioactive components as profound influencing factors for anti-tumor effects. Further research need to be explored for the successful application of Sargassum sp as a potent therapeutic tool against cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6403-6407
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• 2012

Detoxifying enzymes are present in most epithelial cells of the human gastrointestinal tract where they protect against xenobiotics which may cause cancer. Induction of examples such as glutathione S-transferase (GST) and its thiol conjugate, glutathione (GSH) as well as NAD(P)H: quinoneoxidoreductase (NQO1) facilitate the excretion of carcinogens and thus preventing colon carcinogenesis. Pterostilbene, an analogue of resveratrol, has demonstrated numerous pharmacological activities linked with chemoprevention. This study was conducted to investigate the potential of pterostilbene as a chemopreventive agent using the HT-29 colon cancer cell line to study the modulation of GST and NQO1 activities as well as the GSH level. Initially, our group, established the optimum dose of 24 hours pterostilbene treatment using MTT assays. Then, effects of pterostilbene ($0-50{\mu}M$) on GST and NQO1 activity and GSH levels were determined using GST, NQO1 and Ellman assays, respectively. MTT assay of pterostilbene ($0-100{\mu}M$) showed no cytotoxicity toward the HT-29 cell line. Treatment increased GST activity in the cell line significantly (p<0.05) at 12.5 and $25.0{\mu}M$. In addition, treatment at $50{\mu}M$ increased the GSH level significantly (p<0.05). Pterostilbene also enhanced NQO1 activity significantly (p<0.05) at $12.5{\mu}M$ and $50{\mu}M$. Hence, pterostilbene is a potential chemopreventive agent capable of modulation of detoxifiying enzyme levels in HT-29 cells.