Limits...
Enhancement of viability of radiosensitive (PBMC) and resistant (MDA-MB-231) clones in low-dose-rate cobalt-60 radiation therapy.

Falcão PL, Motta BM, de Lima FC, Lima CV, Campos TP - Radiol Bras (2015 May-Jun)

Bottom Line: Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates.MDAMB- 231 cells presented viability decrease only at higher dose and dose rate.The results showed MDA-MB-231 clone expansion at low dose rate after 48-72 hours post-radiation.

View Article: PubMed Central - PubMed

Affiliation: Postdoc, Associate Professor at Universidade Federal do Amazonas (UFAM), Manaus, AM, Brazil.

ABSTRACT

Objective: In the present study, the authors investigated the in vitro behavior of radio-resistant breast adenocarcinoma (MDA-MB-231) cells line and radiosensitive peripheral blood mononuclear cells (PBMC), as a function of different radiation doses, dose rates and postirradiation time kinetics, with a view to the interest of clinical radiotherapy.

Materials and methods: The cells were irradiated with Co-60, at 2 and 10 Gy and two different exposure rates, 339.56 cGy.min(-1) and the other corresponding to one fourth of the standard dose rates, present over a 10-year period of cobalt therapy. Post-irradiation sampling was performed at pre-established kinetics of 24, 48 and 72 hours. The optical density response in viability assay was evaluated and a morphological analysis was performed.

Results: Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates. MDAMB- 231 cells presented viability decrease only at higher dose and dose rate. The results showed MDA-MB-231 clone expansion at low dose rate after 48-72 hours post-radiation.

Conclusion: Low dose rate shows a possible potential clinical impact involving decrease in management of radio-resistant and radiosensitive tumor cell lines in cobalt therapy for breast cancer.

No MeSH data available.


Related in: MedlinePlus

Photo of the cultures submitted to the MTT test, showing two rows of wells withdevelopment of formazan crystals, and image of one of the wells indicating thedevelopment of crystals superimposed to the non-viable cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4492568&req=5

f01: Photo of the cultures submitted to the MTT test, showing two rows of wells withdevelopment of formazan crystals, and image of one of the wells indicating thedevelopment of crystals superimposed to the non-viable cells.

Mentions: According to the calculations performed on the day of the samples irradiation, theutilized dose rates were: standard 339.56 cGy.min-1 (X), and one fourth ofthe standard, corresponding to 84.89 cGy.min-1 (X/4). A quantitativeevaluation of cell viability was performed utilizing the radiosensitive andradioresistant cell lines, respectively, with the purpose of demonstrating that theviable cells after irradiation were capable of forming formazan crystals around themby the cleavage of the tetrazolium salt. After incubation of the cells submitted tothis assay, a dye solution was formed, which was visualized at optical microscope, asshown on Figure 1.


Enhancement of viability of radiosensitive (PBMC) and resistant (MDA-MB-231) clones in low-dose-rate cobalt-60 radiation therapy.

Falcão PL, Motta BM, de Lima FC, Lima CV, Campos TP - Radiol Bras (2015 May-Jun)

Photo of the cultures submitted to the MTT test, showing two rows of wells withdevelopment of formazan crystals, and image of one of the wells indicating thedevelopment of crystals superimposed to the non-viable cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492568&req=5

f01: Photo of the cultures submitted to the MTT test, showing two rows of wells withdevelopment of formazan crystals, and image of one of the wells indicating thedevelopment of crystals superimposed to the non-viable cells.
Mentions: According to the calculations performed on the day of the samples irradiation, theutilized dose rates were: standard 339.56 cGy.min-1 (X), and one fourth ofthe standard, corresponding to 84.89 cGy.min-1 (X/4). A quantitativeevaluation of cell viability was performed utilizing the radiosensitive andradioresistant cell lines, respectively, with the purpose of demonstrating that theviable cells after irradiation were capable of forming formazan crystals around themby the cleavage of the tetrazolium salt. After incubation of the cells submitted tothis assay, a dye solution was formed, which was visualized at optical microscope, asshown on Figure 1.

Bottom Line: Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates.MDAMB- 231 cells presented viability decrease only at higher dose and dose rate.The results showed MDA-MB-231 clone expansion at low dose rate after 48-72 hours post-radiation.

View Article: PubMed Central - PubMed

Affiliation: Postdoc, Associate Professor at Universidade Federal do Amazonas (UFAM), Manaus, AM, Brazil.

ABSTRACT

Objective: In the present study, the authors investigated the in vitro behavior of radio-resistant breast adenocarcinoma (MDA-MB-231) cells line and radiosensitive peripheral blood mononuclear cells (PBMC), as a function of different radiation doses, dose rates and postirradiation time kinetics, with a view to the interest of clinical radiotherapy.

Materials and methods: The cells were irradiated with Co-60, at 2 and 10 Gy and two different exposure rates, 339.56 cGy.min(-1) and the other corresponding to one fourth of the standard dose rates, present over a 10-year period of cobalt therapy. Post-irradiation sampling was performed at pre-established kinetics of 24, 48 and 72 hours. The optical density response in viability assay was evaluated and a morphological analysis was performed.

Results: Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates. MDAMB- 231 cells presented viability decrease only at higher dose and dose rate. The results showed MDA-MB-231 clone expansion at low dose rate after 48-72 hours post-radiation.

Conclusion: Low dose rate shows a possible potential clinical impact involving decrease in management of radio-resistant and radiosensitive tumor cell lines in cobalt therapy for breast cancer.

No MeSH data available.


Related in: MedlinePlus