Publications by authors named "Joshua K S Ko"

Our previous study had demonstrated that Astragalus saponins (AST) could reduce the side effects of orthodox chemotherapeutic drugs, while concurrently promote antitumor activity. In the present study, we attempted to investigate the potential synergistic anticarcinogenic effects of AST and a vinca alkaloid vinblastine (VBL). Reduced expression of key proangiogenic and metastatic factors including VEGF, bFGF, metalloproteinase (MMP)-2, and MMP-9 was detected in VBL-treated colon cancer cells, with further downregulation by combined VBL/AST treatment.

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Aims: Stress has been implicated in the development of cancers. Adrenaline levels are increased in response to stress. The effects of adrenaline on colon cancer are largely unknown.

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Astragalus membranaceus has been used to ameliorate the side effects of antineoplastic drugs because of its immunomodulating nature. We had recently demonstrated that total Astragalus saponins (AST) possess anticarcinogenic and proapoptotic properties in human colon cancer cells and tumor xenograft. In this study, we identified NSAID-activated gene (NAG-1) as a potential molecular target of AST.

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Novel chemotherapeutic agents derived from active phytochemicals could be used as adjuvants and improve the anti-carcinogenicity of standard drug treatments. However, their precise mechanisms of action are sometimes unclear. In this study, the anti-carcinogenic effect of the herbal diterpenoid pseudolaric acid B (PAB) on the growth and apoptosis of colon cancer cells was investigated, and to compare that with the more toxic compound triptolide.

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Astragalus memebranaceus is used as immunomodulating agent in treating immunodeficiency diseases and to alleviate the adverse effects of chemotherapeutic drugs. In recent years, it has been proposed that Astragalus may possess anti-tumorigenic potential in certain cancer cell types. In this study, the anti-carcinogenic effects of Astragalus saponin extract were investigated in HT-29 human colon cancer cells and tumor xenograft.

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The etiology of ulcerative colitis (UC) remains unknown, although the risk of developing UC is apparently higher in non-smokers and ex-smokers. We have demonstrated in a colitis animal model that exposure to tobacco smoke could attenuate UC pathogenesis. The present study aimed to investigate and compare between the modes of action of nicotine and different fractions of tobacco smoke extract in the development of experimental colitis.

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The protective action of zinc compounds in Crohn's disease-like inflammatory bowel disease in animals has been shown. A similar action of zinc sulfate on ulcerative colitis has not been defined. The present study aimed to delineate the protective action of zinc sulfate and the pathogenic mechanisms of 2,4-dinitrobenzene sulfonic acid (DNBS)-induced ulcerative colitis in rats.

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