p38β (MAPK11) mediates gemcitabine-associated radiosensitivity in sarcoma experimental models.
Gemcitabine
MAPK11 (p38β)
MAPK14 (p38α)
Radiosensitivity
Sarcoma
p38MAPK
Journal
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
ISSN: 1879-0887
Titre abrégé: Radiother Oncol
Pays: Ireland
ID NLM: 8407192
Informations de publication
Date de publication:
03 2021
03 2021
Historique:
received:
06
04
2020
revised:
30
11
2020
accepted:
01
12
2020
pubmed:
15
12
2020
medline:
24
4
2021
entrez:
14
12
2020
Statut:
ppublish
Résumé
Gemcitabine is an antitumour agent currently used in the treatment of several types of cancer with known properties as a radiosensitizer. p38MAPK signalling pathway has been shown to be a major determinant in the cellular response to gemcitabine in different experimental models. However, the molecular mechanism implicated in gemcitabine-associated radiosensitivity remains unknown. The human sarcoma cell lines A673 and HT1080, and a mouse cell line derived from a 3-methylcholanthrene induced sarcoma were used as experimental models. Modulation of p38MAPKs was performed by pharmacological approaches (SB203580) and genetic interference using lentiviral vectors coding for specific shRNAs. Viability was assessed by MTT. Gene expression was evaluated by western blot and RT-qPCR. Induction of apoptosis was monitored by caspase 3/7 activity. Response to ionizing radiation was evaluated by clonogenic assays. Our data demonstrate that chemical inhibition of p38MAPK signalling pathway blocks gemcitabine radiosensitizing potential. Genetic interference of MAPK14 (p38α), the most abundantly expressed and best characterized p38MAPK, despite promoting resistance to gemcitabine, it does not affect its radiosensitizing potential. Interestingly, specific knockdown of MAPK11 (p38β) induces a total loss of the radiosensitivity associated to gemcitabine, as well as a marked increase in the resistance to the drug. The present work identifies p38β as a major determinant of the radiosensitizing potential of gemcitabine without implication of p38α, suggesting that p38β status should be analysed in those cases in which gemcitabine is combined with ionizing radiation.
Sections du résumé
BACKGROUND AND PURPOSE
Gemcitabine is an antitumour agent currently used in the treatment of several types of cancer with known properties as a radiosensitizer. p38MAPK signalling pathway has been shown to be a major determinant in the cellular response to gemcitabine in different experimental models. However, the molecular mechanism implicated in gemcitabine-associated radiosensitivity remains unknown.
MATERIALS AND METHODS
The human sarcoma cell lines A673 and HT1080, and a mouse cell line derived from a 3-methylcholanthrene induced sarcoma were used as experimental models. Modulation of p38MAPKs was performed by pharmacological approaches (SB203580) and genetic interference using lentiviral vectors coding for specific shRNAs. Viability was assessed by MTT. Gene expression was evaluated by western blot and RT-qPCR. Induction of apoptosis was monitored by caspase 3/7 activity. Response to ionizing radiation was evaluated by clonogenic assays.
RESULTS
Our data demonstrate that chemical inhibition of p38MAPK signalling pathway blocks gemcitabine radiosensitizing potential. Genetic interference of MAPK14 (p38α), the most abundantly expressed and best characterized p38MAPK, despite promoting resistance to gemcitabine, it does not affect its radiosensitizing potential. Interestingly, specific knockdown of MAPK11 (p38β) induces a total loss of the radiosensitivity associated to gemcitabine, as well as a marked increase in the resistance to the drug.
CONCLUSION
The present work identifies p38β as a major determinant of the radiosensitizing potential of gemcitabine without implication of p38α, suggesting that p38β status should be analysed in those cases in which gemcitabine is combined with ionizing radiation.
Identifiants
pubmed: 33310004
pii: S0167-8140(20)31227-5
doi: 10.1016/j.radonc.2020.12.008
pii:
doi:
Substances chimiques
Deoxycytidine
0W860991D6
Mitogen-Activated Protein Kinase 11
EC 2.7.11.24
Gemcitabine
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
136-144Informations de copyright
Copyright © 2020 Elsevier B.V. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.