Radiation Therapy

Efficient and error-free DNA repair is critical for safeguarding genome integrity, yet it is also linked to radio- and chemoresistance of malignant tumors. miR-34a, a potent tumor suppressor, influences a large set of p53-regulated genes and contributes to p53-mediated apoptosis. However, the effects of miR-34a on the processes of DNA damage and repair are not entirely understood. We explored tet-inducible miR-34a-expressing human p53 wild-type and R273H p53 mutant GBM cell lines, and found that miR-34a influences the broad spectrum of 53BP1-mediated DNA damage response. It escalates both post-irradiation and endogenous DNA damage, abrogates radiation-induced G 2/M arrest and drastically increases the number of irradiated cells undergoing mitotic catastrophe. Furthermore, miR-34a downregulates 53BP1 and inhibits its recruitment to the sites of DNA double-strand breaks. We conclude that whereas miR-34a counteracts DNA repair, it also contributes to the p53-independent elimination of distressed cells, thus preventing the rise of genomic instability in tumor cell populations. These properties of miR-34a can potentially be exploited for DNA damage-effecting therapies of malignancies.

Kofman AV, Kim J, Park SY, Dupart E, Letson C, Bao Y, Ding K, Chen Q, Schiff D, Larner J, Abounader R.

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PURPOSE: Radiation therapy is well established in the treatment of painful plantar fasciitis or heel spur. A retrospective analysis was conducted to investigate the effect of field definition on treatment outcome and to determine the impact of factors potentially...

Tumor hypoxia is a common feature of prostate tumors associated with the stabilization of hypoxia-inducible-factor 1alpha (HIF-1α) and poor prognosis following radiation therapy. Lack of oxygen at the time of irradiation is associated with radioresistance, but recent reports suggest radioresponse is also modulated by the dynamic nature of tumor hypoxia.

Derek Hennessey, Lynn Martin, Anne Atzberger, Thomas Lynch, Donal Hollywood and Laure Marignol

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Non-melanoma skin cancer (NMSC) is the most common malignancy, whose public health significance is often unrecognized. This analysis has two objectives: first, to provide up-to-date incidence estimates by sex, age group, histological type, and body site; and second,...

PURPOSE: The aim of this work was to compare the efficacy of two different dose fractionation schedules for radiotherapy of patients with calcaneodynia. PATIENTS AND METHODS: Between February 2006 and April 2010, 457 consecutive evaluable patients were recruited for...