Progesterone decreases viability and up regulates membrane progesterone receptors expression on the human Chronic Myeloid Leukemia cell line

Progesterone (P4) has an important effect (activatory or inhibitory) on cell proliferation. Although there is evidence of the impact of progesterone on sex-linked cancers, it can affect other cancer cells expressing P4 receptors (PRs). We evaluated the expression of membrane P4 receptors (mPRs) and the viability in progesterone-treated K562 cells to inspect the possible effects route of progesterone on this (CML) cancer cell line. K562 cells were exposed to various concentrations of progesterone or no exposure for 48 and 72 h. The percentage of viability and cells that expressed mPRα and mPRβ were evaluated by MTT test and flow cytometry respectively. Progesterone significantly increased the expression of mPRα and especially mPRβ on the surface of K562 cells and significantly decreased their viability (p ≤ 0.05). Progesterone can reduce viability in K562 cells. Our findings showed that progesterone affects its receptor expression on K562 cells. Thus it may influence the performance of K562 cells in addition to its direct effects on these cells (via binding to its receptors).