Autor: |
Leyton, Julius, Gozes, Yehoshua, Pisegna, Joseph, Coy, David, Purdom, Sally, Casibang, Marchessini, Zia, Farah, Moody, Terry |
Zdroj: |
Breast Cancer Research & Treatment; Jul1999, Vol. 56 Issue 2, p175-184, 10p |
Abstrakt: |
The effects of pituitary adenylate cyclase activating polypeptide (PACAP) analogs were investigated using breast cancer cells. 125I–PACAP–27 bound with high affinity (Kd=5 nM) to T47D cells (Bmax = 29,000 per cell). Specific 125I–PACAP–27 binding was inhibited half maximally by PACAP–27, PACAP–38, PACAP(6–38) and PACAP(28–38) with IC50 values of 8, 17, 750 and >3000 nM, respectively. By RT–PCR, PACAP receptor mRNA was present in MCF–7 and T47D cell lines. Polyclonal antibodies to a PACAP receptor fragment (A–8–C) were elicited. The antibodies were affinity purified, recognized a 60–kDa protein by western blot, and stained malignant cells in breast cancer biopsy specimens by immunohistochemistry. PACAP–27 elevated the cAMP in T47D cells and the increase in cAMP caused by PACAP was inhibited by PACAP(6–38). PACAP–27 stimulated c–fos mRNA in T47D cells and the increase in c-fos gene expression caused by PACAP was reversed by PACAP (6–38). PACAP (6–38) inhibited colony formation using a soft agar assay and inhibited breast cancer xenograft growth in nude mice. These data suggest that PACAP (6–38) functions as a breast cancer PACAP receptor antagonist. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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