Overexpression of Programmed Cell Death 1 Prevents Doxorubicin-Induced Apoptosis Through Autophagy Induction in H9c2 Cardiomyocytes

Syu-Ichi Kanno,Akiyoshi Hara

doi:10.1007/s12012-022-09726-w

Syu-Ichi Kanno, Akiyoshi Hara

Open Access

https://doi.org/10.1007/s12012-022-09726-w

Copy DOI

Abstract

Doxorubicin (DOX) is a potent chemotherapeutic agent; however, it causes severe heart injury via apoptosis induction in many patients. DOX-induced cardiotoxicity is attenuated by activated autophagy in the heart. We previously found that programmed cell death 1 (Pdcd1), an immune checkpoint receptor, inhibits DOX-induced cardiomyocyte apoptosis. In this study, we investigated whether autophagy contributes to the protective role of Pdcd1 against DOX-induced cardiomyocyte apoptosis. We also examined the role of Pdcd1 in DOX-induced apoptosis in cancer cells. Rat cardiomyocyte cell line H9c2 and human cancer cell lines K562 and MCF-7 were transfected with Pdcd1-encoding plasmid DNA to establish Pdcd1-overexpressing cells. Apoptosis and autophagy were determined using a luciferase assay. In H9c2 cells, DOX-induced apoptosis and viability reduction occurred through caspase activation. In particular, Pdcd1 overexpression activated the autophagy pathway through the inhibition of the mammalian target of rapamycin, a major negative regulator of autophagy. Moreover, it prevented DOX-induced cardiomyocyte apoptosis; a similar cardioprotection was observed when normal H9c2 cells (without Pdcd1 overexpression) were treated with rapamycin, an autophagy inducer, before the DOX treatment. Conversely, in cancer cells, Pdcd1 overexpression increased both basal and DOX-induced apoptosis. The role of Pdcd1 in DOX-induced apoptosis in cardiomyocytes and cancer cells was opposing. Pdcd1 signaling prevented DOX-induced apoptosis in cardiomyocytes, through autophagy induction; it enhanced DOX-induced apoptosis in cancer cells. Therefore, Pdcd1 could be a critical molecule for more effective and safer DOX chemotherapy.

Highlights

Doxorubicin (DOX), an anthracycline chemotherapeutic agent, is widely and effectively in the treatment of various solid and hematological malignancies [1, 2]
We have previously reported that the mRNA expression of programmed cell death 1 (Pdcd1 or PD-1) in blood is a predictive and protective factor for DOX-induced cardiotoxicity, and that the cardiomyocyte H9c2 cells in which Pdcd1 was knocked down showed a marked increase in apoptosis upon exposure to DOX [25]
We examined the effects of Pdcd1 overexpression on the DOX-induced apoptosis of human cancer cell lines K562 and MCF-7

Summary

Introduction

Doxorubicin (DOX), an anthracycline chemotherapeutic agent, is widely and effectively in the treatment of various solid and hematological malignancies [1, 2]. The crosstalk between autophagy and apoptosis in DOX-induced cardiotoxicity has been demonstrated in many recent studies. Several findings indicate that the activation of autophagy is effective in reducing DOX-induced cardiac apoptosis and toxicity [9, 16,17,18,19]. Several other findings suggest that autophagy contributes to the development or exacerbation of DOX-induced cardiac apoptosis [20,21,22,23,24]. Rapamycin (Rap), an inducer of autophagy, has been reported to prevent [17, 18] or promote [23] DOXinduced cardiac apoptosis. Preventive [24] or promotive [17] effects on DOX-induced apoptosis have been observed with bafilomycin A1 (Baf), an inhibitor of autophagy. The role of autophagy in DOXinduced apoptosis is inconsistent between studies and remains unclear

Methods

Results

Conclusion