Two human cell lines—ACC-LC-171 non–small-cell lung carcinoma and the U-2 OS osteosarcoma—each transcribe the normal 6.2-kb and 9.6-kb human PTPRG mRNAs, but each also generates two additional mRNAs (Tsukamoto et al., 1992). This evidence concerns the gene PTPRG and osteosarcoma.