Physciosporin suppresses the proliferation, motility and tumourigenesis of colorectal cancer cells.

BACKGROUND: Lichens, which represent symbiotic associations of fungi and algae, are potential sources of numerous natural products. Physciosporin (PHY) is a potent secondary metabolite found in lichens and was recently reported to inhibit the motility of lung cancer cells via novel mechanisms. PURPOSE: The present study investigated the anticancer potential of PHY on colorectal cancer (CRC) cells. METHODS: PHY was isolated from lichen extract by preparative TLC. The effect of PHY on cell viability, motility and tumourigenicity was elucidated by MTT assay, hoechst staining, flow cytometric analysis, transwell invasion and migration assay, soft agar colony formation assay, Western blotting, qRT-PCR and PCR array in vitro as well as tumorigenicity study in vivo. RESULTS: PHY decreased the viability of various CRC cell lines (Caco2, CT26, DLD1, HCT116 and SW620). Moreover, PHY elicited cytotoxic effects by inducing apoptosis at toxic concentrations. At non-toxic concentrations, PHY dose-dependently suppressed the invasion, migration and colony formation of CRC cells. PHY inhibited the motility of CRC cells by suppressing epithelial-mesenchymal transition and downregulating actin-based motility markers. In addition, PHY downregulated ß-catenin and its downstream target genes cyclin-D1 and c-Myc. Moreover, PHY modulated KAI1 C-terminal-interacting tetraspanin and KAI1 expression, and downregulated the downstream transcription factors c-jun and c-fos. Finally, PHY administration showed considerable bioavailability and effectively decreased the growth of CRC xenografts in mice without causing toxicity. CONCLUSION: PHY suppresses the growth and motility of CRC cells via novel mechanisms.

The zoapatle. VII. Antiimplantation effect in the rat of zoapatle aqueous crude extract (ZACE) from Montanoa tomentosa and Montanoa frutescens.

Intrauterine administration of zoapatle aqueous crude extract (ZACE) from Montanoa frutescens on the fourth day of rat pregnancy, at concentrations equivalent to 50 mg and 5 mg of dry leaves, was associated with total inhibition of implantation sites. On the other hand, ZACE from Montanoa tomentosa equivalent to 50 and/or 100 mg of dry leaves, prepared and administered in the same fashion, did not inhibit the number of implants by day 11 of pregnancy. However, most implants were found abnormal, of blue color, poor orientation or spacing; these morphological changes could be considered as reabsorption sites.

The zoapatle. VIII. Ultrastructural changes in endometrium of rats.

Intrauterine administration of Zoapatle aqueous crude extract (ZACE) prepared from Montanoa tomentosa s.s.p. tomentosa, on day 4 of pregnancy, did not alter the normal uterine morphological changes by days 5 and 8 of pregnancy in the rat. On the other hand, ZACE made from Montanoa frutescens caused profound alterations on the uterine structures, such as: focal loss of epithelial lining, thickened blood vessels and alterations in stroma cells in rat endometrium. Morphological alterations correlate well with the antiimplantation effect associated with the intrauterine administration of these plant extracts. Scanning electron micrographs of leaves from Montanoa tomentosa and Montanoa frutescens revealed striking differences in glandular secretion and trichomes.