Only in a single case (bladder carcinoma) the control tissue had a much lower relative amount of PKM2 (54.7%) then the cancer sample (97.1% PKM2), but the change in the percentage resulted predominantly from an up regulation of the PKM2 isoform from 20.8 fmol in the bladder control to 181.9 fmol in the cancer, and not from a switch in alternative splicing. Here, PKM is linked to urinary bladder carcinoma.