Relaxin does not influence the growth of human cervical adenocarcinoma (HeLa) cells in culture.

This study was performed to determine whether relaxin influences the growth of human adenocarcinoma (HeLa) cells of the cervix, which has been shown to contain relaxin-binding sites and proliferate by relaxin. Cells were maintained in Dulbecco's modified Eagle's medium with 5% fetal calf serum. Highly purified porcine relaxin was added at concentrations of 10(-11) to 10(-5) M and incubated for 44, 69, 94, and 118 h. Cell proliferation/cytotoxicity and endogenous nitric oxide production were determined using a colorimetric MTS assay and Griess assay, respectively. The results indicate that whereas relaxin promotes the growth rate of MCF-7 cells, which is in agreement with previous reports, at the doses and times of exposure used in this study relaxin does not significantly influence the number of viable HeLa cells. However, relaxin at nanomolar concentrations (10(-9) to 10(-8) M) promoted the growth of HeLa cells in the presence of both estrogen and progesterone to a small extent. In agreement with these results, relaxin did not affect nitric oxide production. We conclude that relaxin may have differential effects on the growth of two different cancer cell types, MCF-7 and HeLa cells.