BACKGROUND Radiotherapy is the principal modality used to treat early stage laryngeal cancer. Unfortunately treatment failures occur in 10-25% of patients. Subsequent salvage surgery is technically more difficult, with increased complication and failure rates. The ability to predict or prevent radioresistance would improve the poor survival associated with this disease. Cox-2 is an inducible en...

The cancer-prone neurodegenerative disorder, ataxia telangiectasia (A-T), results from mutations of ATM (ataxia telangiectasia mutated). Individuals with A-T are also hypersensitive to ionizing radiation (IR). Cultured cells from A-T individuals or Atm-/- mice have cell cycle and growth defects and are generally considered radiosensitive. However, it has been shown recently that cell population...

Acute Radiation Disease (ARD) or Acute Radiation Syndromes (ARS) are defined as the collective toxic clinical states observed from the acute pathological processes in various doses of irradiated mammals; to include: systemic inflammatory response syndrome (SIRS), toxic multiple organ injury (TMOI), toxic multiple organ dysfunction syndromes (TMODS), and finally, toxic multiple organ failure (TM...

PURPOSE Despite its prominent contribution to cancer cure and palliation, around 1% to 5% of cancer patients suffer serious side effects from radiotherapy. A cardinal goal in the fields of radiobiology and oncology is to predict normal tissue radiosensitivity of a cancer patient before radiotherapy. Higher tumor control rates are likely if radiotherapy individualization could be achieved by app...

The effect of lower doses (0.5e3.0 Gy) of gamma radiation on radiosensitivity of CD3 /CD8þ NK cells subpopulation isolated from the peripheral blood of healthy volunteers was studied 48 h after the irradiation. Only a subtle increase in terms of induction of apoptosis (Aþ cells), was observed in Annexin positive CD3 /CD8þ NK cells. The assessment of the relative presence of CD3 /CD8þ NK cells i...

BACKGROUND Occupational risks, the present nuclear threat, and the potential danger associated with nuclear power have raised concerns regarding the metabolism of plutonium in pregnant women. OBJECTIVE We measured plutonium levels in the milk teeth of children born between 1951 and 1995 to assess the potential risk that plutonium incorporated by pregnant women might pose to the radiosensitive...

The objective of the present study was to determine whether the alterations of cancer predisposition genes were different between radiosensitive and radioresistant patients with Nasopharyngeal Carcinoma (NPC). A total of 21 patients with nasopharyngeal carcinoma were included in this study. All patients were treated with standardized radiotherapy. Sixteen of the tumors were clinically radiosens...

Microscopic examination of individual mammalian cells embedded in agarose, subjected to electrophoresis, and stained with a fluorescent DNA-binding dye provides a novel way of measuring DNA damage and more importantly, of assessing heterogeneity in DNA damage within a mixed population of cells. With this method, DNA double-strand breaks can be detected in populations of cells exposed to X-ray d...

Loss of p53 function has been shown to cause increased resistance to ionizing radiation in normal murine cells; however, the role of p53 in radioresistance of human tumor cells is less clear. Since wild-type p53 function is required for radiation-induced G1 arrest, we measured G1 arrest in 12 human tumor cell lines that have a wide range of radiosensitivities (surviving fraction at 2 Gy, 0.11-0...

Suppressor cell activity which was radiosensitive in most subjects and thymic hormone sensitive in some was identified in patients with cancer, and compared to simultaneously studied normal controls. Suppressor cell activity was measured in cocultures of normal lymphocytes with patient lymphocytes added in microwells using the blastogenic response to phytohemagglutinin and concanavalin A as the...