Only in breast cancer and melanoma did we observe a small, yet statistically-significant, difference in levels of ADMA and total hnRNP-A1, as indicated by the lower ADM-R225/Total ratios, suggesting that hnRNP-A1 may not be completely asymmetrically-dimethylated in these two tumor types. This evidence concerns the gene HNRNPA1 and breast carcinoma.