Cancer-associated fibroblasts-derived gamma-glutamyltransferase 5 promotes tumor growth and drug resistance in lung adenocarcinoma
GGT5 is highly expressed in CAFs. (A) The expression level of GGT5 in normal lung tissues and lung tissues from patients with idiopathic pulmonary fibrosis (IPF) were analyzed using GEO public cohort (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE2052). Data represent mean ± SD. ***, P < 0.001. (B) Western blotting showed the high expression of GGT5 in CAFs than that in paired normal fibroblasts (NFs). β-Actin was also tested as a loading control. The relative expression of GGT5 was indicated in right panel based on the gray value of protein bands (ImageJ software). (C) The expression of GGT5 in NFs and CAFs in vitro were analyzed by immunofluorescent (IF) double-staining with antibodies against GGT5 (red) and Fibronectin (green, a marker of fibroblasts). Scale bare, 50 μm. (D) IF double-staining with antibodies against GGT5 (red) and α-SMA (green, a marker of CAFs) were performed on two LUAD tissue sections. Scale bar, 200 μm. In panels C and D, the cell nuclei were counterstained with DAPI (blue).