Growth hormone-releasing hormone receptor antagonists modify molecular machinery in the progression of prostate cancer.

Therapeutic strategies should be designed to transform aggressive prostate cancer phenotypes to a chronic situation. To evaluate the effects of the new growth hormone-releasing hormone receptor (GHRH-R) antagonists: MIA-602, MIA-606, and MIA-690 on processes associated with cancer progression as cell proliferation, adhesion, migration, and angiogenesis.

We used three human prostate cell lines (RWPE-1, LNCaP, and PC3). We analyzed several molecules such as E-cadherin, β-catenin, Bcl2, Bax, p53, MMP2, MMP9, PCNA, and VEGF and signaling mechanisms that are involved on effects exerted by GHRH-R antagonists.

GHRH-R antagonists decreased cell viability and provoked a reduction in proliferation in LNCaP and PC3 cells. Moreover, GHRH-R antagonists caused a time-dependent increase of cell adhesion in all three cell lines and retarded the wound closure with the highest value with MIA-690 in PC3 cells. GHRH-R antagonists also provoked a large number of cells in SubG0 phase revealing an increase in apoptotic cells in PC3 cell line.

Taken all together, GHRH-R antagonists of the MIAMI series appear to be inhibitors of tumor progression in prostate cancer and should be considered for use in future therapeutic strategies on this malignancy.

The Prostate. 2018 May 10 [Epub ahead of print]

Laura Muñoz-Moreno, Andrew V Schally, Juan C Prieto, M José Carmena, Ana M Bajo

Department of Systems Biology, University of Alcalá, Alcalá de Henares, Madrid, Spain., Veterans Affairs Medical Center, Miami, Florida.