We recently showed that Hepatocyte Growth Factor (HGF), known as a survival factor, unexpectedly enhances apoptosis in human ovarian cancer cells treated with the front-line chemotherapeutics cisplatin (CDDP) and paclitaxel (PTX). Here we demonstrate that this effect depends on the p38 mitogen-activated kinase (MAPK). In fact, p38 MAPK activity is stimulated by HGF and further increased by the combined treatment with HGF and either CDDP or PTX. The expression of a dominant negative form of p38 MAPK abrogates apoptosis elicited by drugs, alone or in combination with HGF. HGF and drugs also activate the ERK1/2 MAPKs, the PI3K/AKT and the AKT substrate mTOR. However, activation of these survival pathways does not hinder the ability of HGF to enhance drug-dependent apoptosis. Altogether data show that p38 MAPK is necessary for HGF sensitization of ovarian cancer cells to low-doses of CDDP and PTX and might be sufficient to overcome activation of survival pathways. Therefore, the p38 MAPK pathway might be a suitable target to improve response to conventional chemotherapy in human ovarian cancer.
p38 MAPK turns hepatocyte growth factor to a death signal that commits ovarian cancer cells to chemotherapy-induced apoptosis
COLTELLA, NADIA;NANO, ELISA;BARDELLA, CHIARA;GRAZIANI A;COMOGLIO, Paolo;DI RENZO, Maria Flavia
2006-01-01
Abstract
We recently showed that Hepatocyte Growth Factor (HGF), known as a survival factor, unexpectedly enhances apoptosis in human ovarian cancer cells treated with the front-line chemotherapeutics cisplatin (CDDP) and paclitaxel (PTX). Here we demonstrate that this effect depends on the p38 mitogen-activated kinase (MAPK). In fact, p38 MAPK activity is stimulated by HGF and further increased by the combined treatment with HGF and either CDDP or PTX. The expression of a dominant negative form of p38 MAPK abrogates apoptosis elicited by drugs, alone or in combination with HGF. HGF and drugs also activate the ERK1/2 MAPKs, the PI3K/AKT and the AKT substrate mTOR. However, activation of these survival pathways does not hinder the ability of HGF to enhance drug-dependent apoptosis. Altogether data show that p38 MAPK is necessary for HGF sensitization of ovarian cancer cells to low-doses of CDDP and PTX and might be sufficient to overcome activation of survival pathways. Therefore, the p38 MAPK pathway might be a suitable target to improve response to conventional chemotherapy in human ovarian cancer.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.