The
colon cancer tissues from
DMH treated rats exhibited higher membrane potential, fluidity and changed
lipid order as examined by
Merocyanine 540 and
1,6-diphenyl-1,3,5-hexatriene, respectively. A transition from gel to liquid crystalline state was observed by
Laurdan fluorescence and also reduced fluorescence quenching of
NBD-PE as contributed in the decreased
membrane lipid phase separation. With
piroxicam, a traditional
NSAID and
c-phycocyanin, a biliprotein from Spirulina platensis, these effects were normalized. An augmented intracellular Ca(+2) had contributed to the
drug mediated apoptosis which is supported by an elevated calpain-9 expression. Histopathologically, a large pool of secreted
acid/neutral mucopolysaccrides as well as the presence of blood vessels and dysplastic crypts signifies invasive
mucinous adenocarcinoma while both the drugs reduced these neoplastic alterations. Wnt/β-
catenin pathway was also found to be up-regulated which served as a crucial
indicator for
cancer cell growth. A concomitant down regulation of PPARγ was noted in
DMH treatment which is associated with
tumor progression. The expression of PPARα and δ, the other two
isoforms of
PPAR family was also modulated. We conclude that
piroxicam and
c-phycocyanin exert their anti-neoplastic effects via regulating membrane properties, raising calpain-9 and PPARγ expression while suppressing Wnt/β-
catenin signaling in experimental colon
carcinogenesis.