Posts Tagged ‘ireland cancer’

Read about “Direct detection and quantification of abasic sites for in vivo studies of DNA damage & repair”

March 30, 2010

Use of chemotherapeutic agents to induce cytotoxic DNA damage and programmed cell death is a key strategy in cancer treatments. However, the efficacy of DNA-targeted agents such as temozolomide is often compromised by intrinsic cellular responses such as DNA base excision repair (BER). Previous studies have shown that BER pathway resulted in formation of abasic or apurinic/apyrimidinic (AP) sites, and blockage of AP sites led to a significant enhancement of drug sensitivity due to reduction of DNA base excision repair. Since a number of chemotherapeutic agents also induce formation of AP sites, monitoring of these sites as a clinical correlate of drug effect will provide a useful tool in the development of DNA-targeted chemotherapies aimed at blocking abasic sites from repair. Here we report an imaging technique based on positron emission tomography (PET) that allows for direct quantification of AP sites in vivo. For this purpose, positron-emitting carbon-11 has been incorporated into methoxyamine ([(11)C]MX) that binds covalently to AP sites with high specificity. The binding specificity of [(11)C]MX for AP sites was demonstrated by in vivo blocking experiments. Using [(11)C]MX as a radiotracer, animal PET studies have been conducted in melanoma and glioma xenografts for quantification of AP sites. Following induction of AP sites by temozolomide, both tumor models showed significant increase of [(11)C]MX uptake in tumor regions in terms of radioactivity concentration as a function of time, which correlates well with conventional aldehyde reactive probe (ARP)-based bioassays for AP sites.

Read the full article on CWRUmedicine.org

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Read about “Non-Hodgkin’s lymphoma in the elderly”

March 30, 2010

The expansion of older population segments and the continuous increase in the incidence of non-Hodgkin’s lymphoma (NHL) makes this group of neoplasms an important and growing problem. Older NHL patients have increased risk of therapy-related toxicity as a result of age-related physiological changes and frequent co-morbidities. A functional assessment of the elderly patient is necessary to determine the likelihood of tolerating and responding to therapy. The comprehensive geriatric assessment (CGA) is one multidisciplinary tool that has been applied successfully to older cancer patients and aids in identification of subjects who will or will not benefit from anti-neoplastic treatment. Although indolent lymphomas present more frequently at advanced stage, randomized trials do not show better outcomes with early therapy, supporting close observation until specific therapeutic indications arise. Use of the monoclonal antibody rituximab as a single agent or in combination with chemotherapy improves survival and has become the standard of care in first-line treatment. Radioimmunoconjugates, bendamustine, and other monoclonal antibodies as well as novel targeted agents also are active against indolent lymphomas. Diffuse large B-cell lymphoma is an aggressive but potentially curable disease. Several trials performed exclusively in elderly patients have demonstrated improved response rates and survival with the addition of rituximab to CHOP (cyclophosphamide, doxorubicin [adriamycin], vincristine, prednisone) chemotherapy in the front-line setting. Salvage chemotherapy followed by autologous haematopoietic cell transplant (autoHCT) has been shown to have better failure-free and overall survival in randomized trials involving younger patients. Highly selected individuals up to age 70 years may attain long-term survival benefit from autoHCT, although transplant-related mortality is higher than in younger patients.

Read the full article on CWRUmedicine.org

Dr. Afshin Dowlati discusses a new way to predict effectiveness of chemotherapy

March 29, 2010

Doctors often have trouble knowing who might respond to certain cancer treatments. “We kind of give chemotherapy and wish for a good result,” says Dr. Afshin Dowlati. That could change.

Dowlati led a study that revealed lung cancer patients with low levels of a molecule that controls cellular interaction have twice the chance of responding to chemotherapy than those with high levels. Those levels can also predict how likely a patient is to live a year after diagnosis. The difference could help patients decide whether to try chemotherapy, drugs or pursue alternative therapies, Dowlati says.

Learn more at CWRUmedicine.org