UNASSIGNED: @entity3957 ( @entity3958 ) is the last gaseous transmitter identified in mammals, and previous studies have reported disparate conclusions regarding the implication of @entity3958 in @entity5 progression. In the present study, we hypothesized that @entity8835 ( @entity8835 ), a fast @entity3958 -releasing donor, might interfere with the mitochondrial respiratory chain of @entity5 cells, increase @entity5 oxygenation, and potentiate the response to irradiation. Using electron paramagnetic resonance (EPR) oximetry, we found a rapid increase in @entity5 @entity4095 after @entity8835 administration (0.1 mmol/kg) in two @entity1 @entity5 models ( @entity0 ), an effect that was due to a decreased @entity26 consumption and an increased @entity5 perfusion. @entity5 irradiated 15 minutes after a single @entity8835 administration were more sensitive to irradiation compared with those that received irradiation alone (increase in growth delay by 50%). This radiosensitization was due to the @entity26 effect, as the @entity851 was abolished when temporarily clamped @entity5 were irradiated. In contrast, daily @entity8835 injection (0.1 mmol/kg/day for 14 days) did not provide any effect on @entity5 growth in vivo. To understand these paradoxical data, we analyzed the impact of external factors on the cellular response to @entity8835 . We found that extracellular pH had a dramatic effect on the cell response to @entity8835 , as the proliferation rate (measured in vitro by @entity1603 incorporation) was increased at pH = 7.4, but decreased at pH = 6.5. Overall, our study highlights the complex role of environmental components in the response of @entity5 cells to @entity3958 and suggests a new approach for the use of @entity3958 donors in combination with radiotherapy. Mol Cancer Ther; 15(1); 1-8.   2015 AACR.

A Fast XXXX -Releasing Donor Increases the Tumor Response to Radiotherapy.

@entity3958 :: ('CHEBI:36945', 'Chemical') :: ['H2S'] @entity1 :: ('9606', 'Species') :: ['human'] @entity1603 :: ('MESH:D001973', 'Chemical') :: ['BrdU'] @entity851 :: ('MESH:D006130', 'Disease') :: ['increased growth delay'] @entity0 :: ('MESH:D001943', 'Disease') :: ['breast MDA-MB-231 and cervix SiHa'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'Tumors', 'tumors', 'cancer'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity8835 :: ('MESH:C025451', 'Chemical') :: ['NaHS', 'sodium hydrosulfide'] @entity3957 :: ('MESH:D006862', 'Chemical') :: ['Hydrogen sulfide'] @entity4095 :: ('MESH:C093415', 'Chemical') :: ['pO2']
@entity3957 :: (MESH:D006862,Chemical) :: ['Hydrogen Sulfide']
