Fig. 1: PTGES/PGE₂ signaling is activated in lung tumor cells of Gprc5a-ko mouse model.

a Representative images of lung tissues stained with H&E and IHC for Ptges of Gprc5a-ko-NNK-12m mice lung tissue, scale bar = 400 μm (mean ± SD (n = 5)). b Metabonomics analysis of the secretion of PGE₂ from NNK-14m-WT and NNK-14m-KO mouse lung tissues (n = 6). c Western blotting analysis of PTGES protein levels in NNK-14m-WT and NNK-14m-KO mouse lung tissues. d Immunoblot analysis of cell lysates from Gprc5a-ko or Gprc5a-wt MTEC with PTGES and GPRC5A antibodies as indicated. e Western blotting analysis of PTGES and ABCG2 protein levels in SJT-1601 cells with and without knockout of Ptges via CRISPR/Cas9 technology. f ELISA kit analysis of the secretion of PGE₂ in MTEC-KO and SJT-1601 cells (n = 3). g ELISA kit analysis of the secretion of PGE₂ from SJT-1601 and SJT-1601-ko-Ptges cell lines (n = 3). h Colony formation assay of SJT-1601 control and SJT-1601-ko-Ptges cells from 3 separate experiments. i Measurement of tumorsphere formation from 3 separate experiments in SJT-1601 and SJT-1601-ko-Ptges cells. Graph shows the mean ± SD percentage; scale bar = 100 μm. j Flow cytometry analysis of CD44⁺ in SJT-1601 and SJT-1601-ko-Ptges cells. k Wound healing and migration analysis of SJT-1601 cells with or without PTGES silencing at 24 hours. Scale bar = 100 μm. l Migration of SJT-1601 cells with or without PTGES silencing analyzed by Transwell migration assay (mean ± SD (n = 3)), scale bar = 100 μm. m Western blotting analysis of PTGES and ABCG2 protein levels in HCC827 and HCC827-shPTGES cell lines. n Flow cytometry analysis of CD44⁺ in HCC827 and HCC827-shPTGES cells (mean ± SD (n = 3)). o Wound healing and migration analysis of HCC827 cells with or without PTGES silencing at 24 hours. Scale bar = 100 μm. p Migration of HCC827 cells with or without PTGES silencing analyzed by Transwell migration assay (mean ± SD (n = 3)), scale bar = 100 μm. *p < 0.05; **p < 0.01; ***p < 0.001.