Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity
As the population ages, more elderly patients require radiotherapy-based treatment for their pelvic malignancies, including muscle-invasive bladder cancer, as they are unfit for major surgery. Therefore, there is an urgent need to find radiosensitising agents minimally toxic to normal tissues, inclu...
Main Authors: | , , , , , , , , , , , , , |
---|---|
Format: | Journal article |
Published: |
American Association for Cancer Research
2017
|
_version_ | 1797066321147461632 |
---|---|
author | Groselj, B Ruan, J Scott, H Gorrill, J Nicholson, J Kelly, J Anbalagan, S Thompson, J Stratford, M Jevons, S Hammond, E Scudamore, C Kerr, M Kiltie, A |
author_facet | Groselj, B Ruan, J Scott, H Gorrill, J Nicholson, J Kelly, J Anbalagan, S Thompson, J Stratford, M Jevons, S Hammond, E Scudamore, C Kerr, M Kiltie, A |
author_sort | Groselj, B |
collection | OXFORD |
description | As the population ages, more elderly patients require radiotherapy-based treatment for their pelvic malignancies, including muscle-invasive bladder cancer, as they are unfit for major surgery. Therefore, there is an urgent need to find radiosensitising agents minimally toxic to normal tissues, including bowel and bladder, for such patients. We developed methods to determine normal tissue toxicity severity in intestine and bladder in vivo, using novel radiotherapy techniques on a small animal radiation research platform (SARRP). The effects of panobinostat (PAN) on in vivo tumour growth delay were evaluated using subcutaneous xenografts in athymic nude mice. PAN concentration levels in xenografts, plasma and normal tissues were measured in CD1-nude mice. CD1-nude mice were treated with drug/irradiation combinations to assess acute normal tissue effects in small intestine using the intestinal crypt assay, and later effects in small and large intestine at 11 weeks by stool assessment and at 12 weeks by histological examination. In vitro effects of PAN were assessed by qPCR and of PAN, TMP195 and mocetinostat by clonogenic assay, and western blot. PAN resulted in growth delay in RT112 bladder cancer xenografts but did not significantly increase acute (3.75 days) or 12 weeks’ normal tissue radiation toxicity. Radiosensitisation by PAN was effective in hypoxic bladder cancer cells and associated with class I HDAC inhibition, and protein downregulation of HDAC2 and MRE11. Pan-HDAC inhibition is a promising strategy for radiosensitisation, but more selective agents may be more useful radiosensitisers clinically, resulting in fewer systemic side effects. |
first_indexed | 2024-03-06T21:40:47Z |
format | Journal article |
id | oxford-uuid:47d7a856-ac91-4b02-ab2a-1c64b1e02b83 |
institution | University of Oxford |
last_indexed | 2024-03-06T21:40:47Z |
publishDate | 2017 |
publisher | American Association for Cancer Research |
record_format | dspace |
spelling | oxford-uuid:47d7a856-ac91-4b02-ab2a-1c64b1e02b832022-03-26T15:22:28ZRadiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicityJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:47d7a856-ac91-4b02-ab2a-1c64b1e02b83Symplectic Elements at OxfordAmerican Association for Cancer Research2017Groselj, BRuan, JScott, HGorrill, JNicholson, JKelly, JAnbalagan, SThompson, JStratford, MJevons, SHammond, EScudamore, CKerr, MKiltie, AAs the population ages, more elderly patients require radiotherapy-based treatment for their pelvic malignancies, including muscle-invasive bladder cancer, as they are unfit for major surgery. Therefore, there is an urgent need to find radiosensitising agents minimally toxic to normal tissues, including bowel and bladder, for such patients. We developed methods to determine normal tissue toxicity severity in intestine and bladder in vivo, using novel radiotherapy techniques on a small animal radiation research platform (SARRP). The effects of panobinostat (PAN) on in vivo tumour growth delay were evaluated using subcutaneous xenografts in athymic nude mice. PAN concentration levels in xenografts, plasma and normal tissues were measured in CD1-nude mice. CD1-nude mice were treated with drug/irradiation combinations to assess acute normal tissue effects in small intestine using the intestinal crypt assay, and later effects in small and large intestine at 11 weeks by stool assessment and at 12 weeks by histological examination. In vitro effects of PAN were assessed by qPCR and of PAN, TMP195 and mocetinostat by clonogenic assay, and western blot. PAN resulted in growth delay in RT112 bladder cancer xenografts but did not significantly increase acute (3.75 days) or 12 weeks’ normal tissue radiation toxicity. Radiosensitisation by PAN was effective in hypoxic bladder cancer cells and associated with class I HDAC inhibition, and protein downregulation of HDAC2 and MRE11. Pan-HDAC inhibition is a promising strategy for radiosensitisation, but more selective agents may be more useful radiosensitisers clinically, resulting in fewer systemic side effects. |
spellingShingle | Groselj, B Ruan, J Scott, H Gorrill, J Nicholson, J Kelly, J Anbalagan, S Thompson, J Stratford, M Jevons, S Hammond, E Scudamore, C Kerr, M Kiltie, A Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title | Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title_full | Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title_fullStr | Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title_full_unstemmed | Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title_short | Radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
title_sort | radiosensitation in vivo by histone deacetylase inhibition with no increase in early normal tissue radiation toxicity |
work_keys_str_mv | AT groseljb radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT ruanj radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT scotth radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT gorrillj radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT nicholsonj radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT kellyj radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT anbalagans radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT thompsonj radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT stratfordm radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT jevonss radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT hammonde radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT scudamorec radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT kerrm radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity AT kiltiea radiosensitationinvivobyhistonedeacetylaseinhibitionwithnoincreaseinearlynormaltissueradiationtoxicity |