Extended use of intravenous bisphosphonate therapy for the prevention of skeletal complications in patients with cancer

We show that TAP/Sec14L2 had a high expression in normal/benign breast, prostate, and liver tissues as compared to lung, colon, and kidney. Its expression was downregulated in breast cancer cell lines shown by quantitative-PCR. Further, 57% of 141 human invasive breast carcinomas had no or markedly reduced TAP/Sec14L2 expression by immunohistochemical staining, and the rate increased to 80% in high grade invasive carcinomas ( p <.01). This downregulation of TAP/Sec14L2 was also present in ductal carcinoma in situ(DCIS) associated with invasive carcinomas. These findings raise the possibility that TAP/Sec14L2 may serve as a tumor suppressor in breast carcinogenesis.