PKM and colorectal cancer: In glioblastoma, renal clear cell carcinoma, bladder cancer, and colorectal cancer, PTBP1 promotes the conversion of PKM from PKM1 isoform to PKM2 isoform through inhibition of exon 10 of pyruvate kinase (PKM; Pyruvate Kinase M1/2) hnRNA, which facilitates the proliferation of tumour cells through the Warburg effect [62, 103].