I am confused about these two cell lines- Caco2 and HT 29. both seems to be similar but compound that causes antiproliferation & apoptosis in caco2 means its harmfull to colon whereas apoptosis in HT-29 cells are not. can anyone clarify this
Dear Shubha Likitha, it is the growth condition that matters. These cell lines if grown in low glucose medium, normal colon epithelium will be mimicked, whereas in high glucose conditions cancerous conditions are represented to more extent. Hope this clarifies your question.
Just the difference in the susceptibility to the COMPOUND does not mean the toxicity to intestinal epithelial cells in vivo. Whereas, Caco2 is established from an old-aged male patient with colon adenocarcinoma, HT29 is established a female patient with colon adenocarcinoma. However, as you know well, there is a heterogeneity in the same tumor tissue, so that the established cell line is not necessarily homogeneous and further cannot reflect the response in vivo.
That is why you have to check what brings about the apoptosis in Caco2 cells but not in HT29 cells. p53 expression pattern? or bcl-2-mediated apoptosis program?
I agree with Dr. Yoshida that the difference in the susceptibility to the COMPOUND does anyhow relate to the toxicity to intestinal epithelial cells in vivo. I think that rather apoptosis-inducing factor (AIF) is DIFFERENTLY involved in apoptosis of Caco2 and HT 29 induced by EPEC. Infection of intestinal epithelial cells in vitro with EPEC led to the mitochondrial and cytosolic accumulation of AIF. This effect was partially dependent on caspase activity. Knockdown of AIF with siRNA blocked cellular apoptosis in response to EPEC infection, as assessed by poly(ADP-ribose) polymerase cleavage and oligonucleosome formation. Taken together, please considers that caspase-dependent mobilization of AIF differently contributes to EPEC-induced epithelial cell apoptosis in Caco2 and HT 29.
My confusion is- people report that anticancer properties of some extracts on caco2/ht29 by inducing apoptosis.
we know that these cell lines are used to mimic the colon epithelium for studies of effect of compound on absorption of dietary compounds, adhesion etc. Disruption of their integrity will lead to ulcers. then how to relate their (caco2/ht29) apoptosis by compound to colon health?