Modification of protein secondary structure as an indicator of radiation-induced abscopal effect: A spectroscopic investigation.

In this study, we investigate the abscopal effect induced in the brain, lung and kidney as a result of partial irradiation of experimental animals with 2 Gy γ-rays. Modifications in the protein secondary structure were used as indicator for the abscopal effect. FTIR spectroscopy and analysis of the amide I and amide II absorption bands suggested possible modifications in the protein secondary structure in the brain and kidney following irradiation.

Influence of ionizing radiation and cell density on the kinetics of autocrine destruction and intercellular induction of apoptosis in precancerous cells.

Intercellular induction of apoptosis (IIA) represents a well-defined signaling model by which precancerous cells are selectively eradicated through reactive oxygen/nitrogen species and cytokine signaling from neighbour normal cells. Previously, we demonstrated that the IIA process could be enhanced by exposure of normal cells to very low doses of ionizing radiation as a result of perturbing the intercellular signaling. In this study, we investigate the kinetic behaviour of both autocrine destruction (AD) and IIA as a function of cell density of both precancerous and normal cells using an insert co-culture system and how exposure of normal cells to ionizing radiation influence the kinetics of apoptosis induction in precancerous cells.

Radio-sensitizing effect of a cocktail of phytochemicals on HepG2 cell proliferation, motility and survival.

Radio-resistance is a major hurdle challenging oncologist worldwide. Despite their anti-cancer characteristics, the implication of phytochemicals in clinical trials is still limited. This study is designed to evaluate the anticancer characteristics and radio-sensitizing effect of a cocktail of seven phytochemicals on HepG2 cells.

Effect of low-dose X-rays on the liver of whole-body irradiated rats.

Purpose: To investigate the effect of whole-body low-dose radiation (10 cGy of 6 MV x-rays) given prior to a challenging dose of 2 Gy x-rays on adaptive response in the liver of rats Material and methods: Rats were either irradiated with 10 cGy, 2 Gy or 10 cGy 24 h prior to 2 Gy (10 cGy-2 Gy irradiated). Liver samples were analyzed for apoptosis, caspase-3, Bcl-2, by flow cytometry. DNA damage was determined by alkaline comet assay.

Radiation induced bystander effects in the spleen of cranially-irradiated rats.

Objective: To investigate the radiation-induced abscopal effect in terms of oxidative stress, apoptosis and DNA damage in the spleen cells following cranial X-rays irradiation of rats.

Methods: Rats were cranially irradiated using 2 Gy X-rays. Another group was whole-body irradiated with 2 Gy X-rays and a third group was exposed to scattered radiation (measured to be 3 mGy).

Enhancement of Peroxidase Release from Non-Malignant and Malignant Cells through Low-Dose Irradiation with Different Radiation Quality.

The release of peroxidase by nontransformed or transformed fibroblasts or epithelial cells (effector cells) triggers apoptosis induction selectively in transformed fibroblasts or transformed epithelial cells (target cells) through intercellular apoptosis-inducing signaling. The release of peroxidase can be induced either by treatment with transforming growth factor beta 1 or by low doses of alpha particles, gamma rays or ultrasoft X rays. In addiation, data indicates that radiation quality does not determine the overall efficiency of peroxidase release and the effects among a wide range of radiation doses are indistinguishable.

The role of radiation quality in the stimulation of intercellular induction of apoptosis in transformed cells at very low doses.

An important stage in tumorigenesis is the ability of precancerous cells to escape natural anticancer signals. Apoptosis can be selectively induced in transformed cells by neighboring normal cells through cytokine and ROS/RNS signaling. The intercellular induction of apoptosis in transformed cells has previously been found to be enhanced after exposure of the normal cells to very low doses of both low- and high-LET ionizing radiation.

Intercellular induction of apoptosis signalling pathways.

Intercellular signalling plays an important role in the progression of a transformed cell to a tumour. In order to characterise the underlying mechanisms, a well-defined model cell system of intercellular induction of apoptosis was used where neighbouring normal cells can selectively eliminate transformed cells. In the absence of non-transformed cells, the induction of apoptosis in transformed 208Fsrc3 cells occurs via autocrine destruction and is dominated by peroxidase (PO), which initiates the PO/hypochlorous acid signalling pathway at high local cell densities.