| First Author | Jakowlew SB | Year | 1998 |
| Journal | Mol Carcinog | Volume | 22 |
| Issue | 1 | Pages | 46-56 |
| PubMed ID | 9609100 | Mgi Jnum | J:48235 |
| Mgi Id | MGI:1267001 | Doi | 10.1002/(sici)1098-2744(199805)22:1<46::aid-mc6>3.0.co;2-j |
| Citation | Jakowlew SB, et al. (1998) Reduction in transforming growth factor-beta type II receptor in mouse lung carcinogenesis. Mol Carcinog 22(1):46-56 |
| abstractText | Transforming growth factor-beta (TGF-beta) is a growth modulator that inhibits the proliferation of many epithelial cells through interaction with its receptors, the type I and type II receptors (TGF-beta RI and RII) by activating their serine/threonine kinase activities. Loss of growth inhibition by TGF-beta is thought to contribute to the development of many types of tumors. To examine the roles of TGF-beta1, -beta2, and -beta3 and TGF-beta RI and RII in chemically induced mouse lung tumorigenesis, we used immunohistochemical and in situ hybridization analyses to measure the expression of their proteins and mRNAs in A/J mice treated with the carcinogen urethane to induce lung adenomas. Immunostaining for the TGF-beta ligands and receptors was detected in the epithelia of the bronchioles of untreated and treated A/J mice at similar levels. Immunostaining for the TGF-beta ligands and receptors was also detected in adenomas by 2 mo. While immunostaining for TGF-beta1, -beta2, and -beta3 and TGF-beta RI in adenomas was detected at levels comparable to those in bronchioles, immunostaining for TGF-beta RII was less intense in adenomas than in bronchioles. Decreased immunostaining for TGF-beta RII in adenomas persisted for at least 8 mo after exposure to urethane, whereas immunostaining for TGF-beta1, -beta2, and -beta3 and TGF-beta RI persisted at levels comparable to those in normal bronchioles. In situ hybridization studies conducted with TGF-beta receptor riboprobes showed a corresponding reduction in expression of TGF-beta RII mRNA but not of TGF-beta RI mRNA in adenomas compared with expression in bronchioles. Expression of TGF-beta RII mRNA was also examined in non-tumorigenic and tumorigenic mouse lung cells; expression of TGF-beta RII mRNA was lower in the tumorigenic cells derived from urethane-induced lung tumors. These data suggest that a decrease in expression of TGF-beta RII may contribute to autonomous cell growth and may play an important role in mouse lung carcinogenesis induced by urethane. |
