the cancer of oral cavity is related to lesions of mucous membrane of tongue and gum that can be treated with radiation therapy. a lateral photon field can be used to treat this kind of tumor, which has a side‑effect on normal tissue in the opposite side of the oral cavity. in this study the dosimetric effect of the various shields in oral cavity is evaluated. in this study, a special phantom s...

  Ionizing radiation has long been known to produce detrimental biological effects. Although these harmful effects are the results of high doses of exposure, some other maladies such as mutation and cancer seems  to be induced at low doses of exposure. In recent decades, however, some pioneer scientists have indicated that ionizing radiation like many other essential agents has toxic effects  ...

physical agents such as ultraviolet or ionizing radiation and repetitive trauma have been related to the causation of cancer in humans. much less clear is the association between exposure to radiofrequency, such as radar and microwave radiation to the development of cancer. sporadic case reports and small series suggest that this type of radiation might lead to cancer or contribute to its evolu...

BACKGROUND Radiotherapy (RT) is one of the major non-operative treatment modalities for treating lung cancer. Tomotherapy is an advanced type of intensity-modulated radiotherapy (IMRT) in which radiation may be delivered in a helical fashion. However, unexpected pneumonitis may occur in patients treated with tomotherapy, especially in combination with chemotherapy, as a result of extensive low-...

Breast-conserving surgery followed by radiotherapy is the standard of care for most women with early-stage breast cancer, resulting in excellent long-term survival. Post-treatment, however, the rate of second breast cancers is significant; for example, the average ipsilateral second-cancer rate from four long-term studies is 13% after 15 years, and increases with still longer follow-up times. R...

naturally occurring radionuclide of terrestrial origin (also called primordial radionuclide) are present in various degrees in all media in the environment, including the human body itself. their concentrations in environment decrease continually by decaying. the main objective of this study is to evaluate the radioactivity levels and health risks due to terrestrial radionuclide in soil of yalo...

Survivin is overexpressed in most human cancers, including pancreatic adenocarcinoma. Expression of survivin is regulated by specificity protein (Sp) proteins and related to resistance to radiation therapy. Tolfenamic acid induces Sp protein degradation in several cancer cell lines. The purpose of this study is to investigate whether tolfenamic acid inhibits survivin expression and sensitizes p...

Radioresistance markedly impairs the efficacy of tumor radiotherapy and involves antiapoptotic signal transduction pathways that prevent radiation-induced cell death. The majority of human prostate cancers overexpress the important antiapoptotic proteins Bcl-2 and/or Bcl-xL, which render tumors resistant to radiation therapy. (-)-Gossypol, a natural polyphenol product from cottonseed, has recen...

The control of radioresistance and metastatic potential of surviving cancer cells is important for improving cancer eradication by radiotheraphy. The distal-less homeobox2 (DLX2) gene encodes for a homeobox transcription factor involved in morphogenesis and its deregulation was found in human solid tumors and hematologic malignancies. Here we investigated the role of DLX2 in association with ra...

To understand one of the mechanisms of resistance to chemoradiation in colon cancer cells, we investigated whether 5-fluorouracil (5-FU) mediated the expression of epidermal growth factor receptor (EGFR) and modified repair of radiation-induced DNA damage, especially in a p53 independent pathway. Cytotoxicity was determined for 5-FU combined with radiation for three colon cancer cell lines that...