ARHI/NOEY2 inactivation may be important in breast tumor pathogenesis.

Allelic loss frequently occurs on the short arm of chromosome 1 in human breast carcinoma, suggesting that the ARHI/NOEY2 gene, an imprinted putative tumor suppressor gene, is involved in the pathogenesis of the tumor entity. To clarify the clinical importance of ARHI/NOEY2 mRNA in breast cancer, we studied whether ARHI/NOEY2 inactivation might contribute to tumors arising in the breast. An ARHI/NOEY2 message was detected by real-time PCR analysis in all noncancerous breast tissues, but was not detected in 2 of 26 breast cancer tissue samples. In 10 of 26 breast cancer tissue samples ARHI/NOEY2 mRNA was substantially reduced. ARHI/NOEY2 expression was lost or markedly reduced in 12 of 26 (46.15%) breast cancer tissue samples. In summary, we conclude that decreased ARHI/NOEY2 mRNA expression may play an important role in the pathogenesis of breast cancer.