Radiation can modulate surface expression of some but not all TNF family death receptors in colorectal tumor cell lines.

<p>SW620, WiDr and HCT116 cells received 0 (black bar), 2.5 (dark grey bar), 5 (light gray bar) and 10 Gy (white bar) of radiation. Cells were re-cultured for 72 h and then analyzed by flow cytometry for surface (A) LTβR, (B) TNF-R1, (C) DR4, and (D) DR5 surface expression (inset; MFI of DR5 expression is shown for SW620 and HCT116 cells). Percent of cells expressing each death receptor is graphed. Cells stained with a fluorescently-labeled isotype control antibodies were negative (not shown). Staining was repeated 3 times with similar results.