1
|
Digiacomo G, Fumarola C, La Monica S, Bonelli MA, Cretella D, Alfieri R, Cavazzoni A, Galetti M, Bertolini P, Missale G, Petronini PG. Simultaneous Combination of the CDK4/6 Inhibitor Palbociclib With Regorafenib Induces Enhanced Anti-tumor Effects in Hepatocarcinoma Cell Lines. Front Oncol 2020; 10:563249. [PMID: 33072590 PMCID: PMC7539564 DOI: 10.3389/fonc.2020.563249] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/20/2020] [Indexed: 12/28/2022] Open
Abstract
Advanced hepatocarcinoma (HCC) is an aggressive malignancy with poor prognosis and limited treatment options. Alterations of the cyclin D-CDK4/6-Rb pathway occur frequently in HCC, providing the rationale for its targeting at least in a molecular subset of HCC. In a panel of HCC cell lines, we investigated whether the CDK4/6 inhibitor palbociclib might improve the efficacy of regorafenib, a powerful multi-kinase inhibitor approved as second-line treatment for advanced HCC after sorafenib failure and currently under clinical investigation as first-line therapy in combination with immunotherapy. In Rb-proficient cells, the simultaneous drug combination, but not the sequential schedules, inhibited cell proliferation, either in short or in long-term experiments, and induced cell death more strongly than individual treatments. Moreover, the combination significantly reduced spheroid cell growth and inhibited cell migration/invasion. The superior efficacy of palbociclib plus regorafenib emerged also under hypoxia and was associated with a significant down-regulation of CDK4/6-Rb-myc and mTORC1/p70S6K signaling. Moreover, regorafenib suppressed palbociclib-induced expression of cyclin D1 contributing to the cytotoxic effects of the combination. Besides these inhibitory effects on cell viability/proliferation, palbociclib and regorafenib reduced glucose uptake, although this effect was dependent on the cell model and on the oxygen availability (normoxia or hypoxia). Palbociclib and regorafenib combination impaired glucose uptake and utilization, down-regulating basal and hypoxia-induced expression of HIF-1α, HIF-2α, GLUT-1, and MCT4 proteins as well as the activity/expression of glycolytic enzymes (HK2, PFKP, aldolase A, PKM2). In addition, regorafenib alone reduced mitochondrial respiration. The combined treatment impaired glucose metabolism and respiration without enhancing the effects of the single agents. Our findings provide pre-clinical evidence for the effectiveness of palbociclib and regorafenib combination in HCC cell models.
Collapse
Affiliation(s)
| | - Claudia Fumarola
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Silvia La Monica
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Mara A Bonelli
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Daniele Cretella
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Roberta Alfieri
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Andrea Cavazzoni
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Maricla Galetti
- Istituto Nazionale per l'Assicurazione contro gli Infortuni sul Lavoro (INAIL) Research, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, Rome, Italy
| | - Patrizia Bertolini
- Paediatric Hematology Oncology Unit, University Hospital of Parma, Parma, Italy
| | - Gabriele Missale
- Department of Medicine and Surgery, University of Parma, Parma, Italy.,Unit of Infectious Diseases and Hepatology, University Hospital of Parma, Parma, Italy
| | | |
Collapse
|