mRNA Expression of Transforming Growth Factor Alpha in Human Breast Carcinomas and Its Activity in Effusions of Breast Cancer Patients

Abstract

Transforming growth factor alpha (TGFα) mRNA expression was measured by Northern blot analysis in 18 human, primary, infiltrating, ductal breast carcinomas. Expression of a 4.8-kilobase TGFα mRNA transcript was detected in nine of 18 tumors. No evidence was observed of any gross amplifications or major rearrangements of the TGFα gene in the breast carcinoma specimens. Biologically active and immunoreactive TGFα was measured in the pleural effusions or in the ascitic fluids from 37 noncancer and 63 cancer patients. The TGFα activity detected ranged from 0.2 to 26 ng/mL in most effusions from both groups. However, 29 of 63 (46%) of the effusions from cancer patients exhibited TGFα levels that were 6 ng/mL or higher, whereas only seven of 37 (19%) of those from noncancer patients exceeded this level (P<.03). In particular, effusions obtained from breast cancer patients showed a significantly higher level of TGFα, compared with those from noncancer patients (P<.001). Effusions from 14 cancer patients also contained elevated levels of two tumor-associated antigens, CEA and/or TAG-72, and within this group, nine also had elevated levels of TGFα. [J Natl Cancer Inst 81:1165–1171, 1989]