The interruption of atypical PKC signaling and Temozolomide combination therapy against glioblastoma.

Abstract

Current treatment options of glioblastoma include chemotherapy and limited surgical resection. Temozolomide (TMZ) is the current therapeutic choice for chemotherapy. Still, it has severe limitations due to the development of resistance that occurs by genetic modification and constitutive activation of several cell signaling pathways. Therefore, it is essential to develop combination therapy of TMZ with other novel compounds to prevent the development of chemo-resistance. In this study, we used two inhibitors; ICA, an inhibitor of PKC-ι and ζ-Stat, an inhibitor of PKC-ζ. T98G and U87MG glioblastoma cells were treated with either ICA or ζ-stat or TMZ monotherapies, as well as TMZ were combined with either ICA or ζ-stat for five consecutive days. Our in vitro results exhibited that ICA when combined with TMZ, significantly decreased the viability of cancerous cells compared with untreated or TMZ or ICA monotherapies. Additionally, glioblastoma cells were remarkably undergoing apoptosis against the combination treatment of TMZ and ICA nucleotide compared with untreated control cells, as suggested by our Annexin-V/PI flow cytometric analysis. Moreover, the combination of TMZ and ICA also decreased the invasion of glioblastoma cell lines by acting on FAK/Paxillin pathway, as evidenced by scratch assay, transwell invasion assay, Western blot and immunoprecipitation analysis. Furthermore, our in vivo data presented that the combination of ICA and TMZ also reduced glioblastoma tumor growth and volume in mice. These data suggest that atypical PKCs, particularly PKC-ι might be an important therapeutic target as adjuvant therapy in the treatment of glioblastoma.

• Authors: Avijit Dey, S M Anisul Islam, Rekha Patel, Mildred Acevedo-Duncan
• Journal: Cellular signalling (Cell Signal) Vol. 77 Pg. 109819 (01 2021) ISSN: 1873-3913 [Electronic] England
• PMID: 33147518 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.

Chemical References

• Isoenzymes
• Protein Kinase Inhibitors
• RNA, Small Interfering
• Focal Adhesion Kinase 1
• Protein Kinase C
• protein kinase C lambda
• Temozolomide

Topics

• Actin Cytoskeleton (drug effects)
• Animals
• Apoptosis (drug effects)
• Cell Line, Tumor
• Cell Movement (drug effects)
• Drug Therapy, Combination
• Focal Adhesion Kinase 1 (metabolism)
• Glioblastoma (drug therapy, pathology)
• Humans
• Isoenzymes (antagonists & inhibitors, genetics, metabolism)
• Mice
• Mice, Nude
• Protein Kinase C (antagonists & inhibitors, genetics, metabolism)
• Protein Kinase Inhibitors (pharmacology, therapeutic use)
• RNA Interference
• RNA, Small Interfering (metabolism)
• Signal Transduction (drug effects)
• Temozolomide (pharmacology, therapeutic use)
• Transplantation, Heterologous