An adjuvant chemotherapeutic agent in gastric cancer therapy

Peritoneal carcinomatosis can be thought of as a series of events that together form a peritoneal metastatic cascade.

The peritoneal stromal tissue appears to be a friendly host for tumour proliferation, providing a rich source of growth factors and chemokines known to be involved in tumour metastasis. Till now, our understanding of the molecular mediators that orchestrate this cascade is weakly understood. Astragalus memebranaceus,a traditional chinese herbal medicine used for the treatment of common cold , diarrhea, fatigue anorexia and cardiac diseases. In recent years, it has been proposed that Astragalus may possess anti-apoptosis potential in peritoneal mesothelial cell. In spite of this, the anti-apoptosis effects of Astragalus saponin extract in human peritoneal mesothelial cells during peritoneal carcinomatosishas has not been studied. In this study, the anti-apoptosis effects of Astragalus saponin extract were investigated in human peritoneal mesothelial cells during peritoneal gastric cancer metastasis.

A research article to be published on February 7, 2009 in the World Journal of Gastroenterology addresses this question. The research team led by Professor Hui-Mian Xu from Department of Oncology, The First Affiliated Hospital, China Medical University.Human peritoneal mesothelial cell line HMrSV5 was co-incubated with gastric cancer cell supernatant and/or Astragalus injection. Morphological changes were observed. Apoptosis was determined by transmission electron microscope. Apoptosis was also quantified by two methods: the detection of acridine orange/ethidium bromide-stained condensed nuclei by fluorescent microscopy and flow cytometry. The expressions of Bcl-2 and Bax were evaluated by immunostaining.

After 24h of being treated with gastric cancer cell supernatant, mesothelial cells presented morphological changes, exfoliation happened and naked areas appeared.

Cell supernatant from gastric cancer cell MKN45 were effective in inducing apoptosis in mesothelial cells in a time-dependent manner. Obvious morphological changes of cell apoptosis were found. Astragalus injection could partly suppress these changes, as well as regulate the expressions of Bcl-2 and Bax in mesothelial cells. These findings demonstrated that gastric cancer cell could induce the apoptosis of human peritoneal mesothelial cell through its supernatant. Astragalus injection could inhibit this kind of phenomenon and therefore, might represent an adjuvant chemotherapeutic agent in gastric cancer therapy.