Immunohistochemistry for SULT1E1
Tumor and its corresponding surrounding tissues were embedded in paraffin, serially sectioned at 5μM by an automated cryostat slicing machine (Leica Bio systems). Sections were deparaffinized by baking at 60 c followed by xylene treatment, downgraded alcohol and water. Slides were washed with PBST containing 1% casein for 10 minutes, tissue sections were incubated with 5% casein for 30 minutes for preventing non-specific binding followed by overnight incubation in primary antibody SULT1E1 and HIF1αin 1% casein PBST, washed with 1% PBST and incubated in 1% casein PBST containing secondary antibody for 1 hour, washed with 1% PBST followed by water and stained with chromogenic substrate DAB for 3 minutes and then washed with water. Slides were fixed with mounting medium and observed under a microscope (Nikon, Eclipse LV100, magnification 20X) to study the SULT1E1 expression and localization.