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Biomedical subjects

C Norman Coleman

Publications and source records attributed to C Norman Coleman.

17 recordsLinked to original sources

Evaluation of copper chelation agents as anti-angiogenic therapy.

The design, synthesis and evaluation of N,N',N"-tris(2-pyridylmethyl)-cis,cis-1,3,5,-triaminocyclohexane (tachpyr, 1) derivatives as novel anti-angiogenic agents were performed in an in vitro endothelial cell proliferation assay to assess their cytotoxicity and selectivity. The selective nature of the anti-angiogenic agents for human umbilical vein endothelial cells (Huvec) was compared to a normal fibroblast cell line and a human Glioma cell line to evaluate these compounds. N,N',N"-tris(2-mercaptoethyl)-cis,cis-1,3,5-triaminocyclohexane trihydrochloride (3b) was superior to tachpyr in terms of selectivity of its inhibitory activity toward the proliferation of Huvec compared to the fibroblast and human Glioma cell lines.

Angiogenesis Inhibitors↗

Ibuprofen-mediated reduction of hypoxia-inducible factors HIF-1alpha and HIF-2alpha in prostate cancer cells.

PURPOSE: Hypoxia-inducible factors HIF-1alpha and HIF-2alpha are considered to be potential targets for antineoplastic therapy because they regulate the expression of genes that contribute to tumor cell survival, aggressiveness, and angiogenesis. Nonsteroidal anti-inflammatory drugs (NSAIDs) have gained considerable interest as anticancer agents because of their cytotoxic and antiangiogenic properties. The aim of this study was to investigate whether NSAIDs inhibit HIFs and HIF-regulated gene expression in prostate cancer cells. EXPERIMENTAL DESIGN: PC3 and DU-145 cells were treated with ibuprofen (Ibu) and other NSAIDs under normoxic and hypoxic (95% N(2), 5% CO(2); <10 ppm O(2)) conditions. The effect of NSAIDs on HIF proteins was analyzed by Western blot analysis. HIF-regulated proteins, vascular endothelial growth factor (VEGF) and glucose transporter-1 (Glut-1), were analyzed by ELISA and Western blot analysis, respectively. RESULTS: Exposure of PC3 and DU-145 cells to hypoxic condition up-regulated HIF-1alpha and HIF-2alpha proteins. Treatment with Ibu under normoxic and hypoxic conditions reduced the level of HIF-1alpha and HIF-2alpha. Ibu-mediated down-regulation of HIFs was associated with down-regulation of HIF-regulated proteins VEGF and Glut-1 in cells exposed to hypoxia. Other nonspecific NSAIDs, diclofenac and ketorolac, also inhibited HIF-1alpha and HIF-2alpha. The reduction in HIFs was observed in PC3 cells that expressed cyclooxygenase-2 (COX-2) protein as well as in DU-145 cells, which did not express COX-2 protein. COX-2-specific inhibitor NS-398 did not inhibit HIF-1alpha or VEGF and GLUT-1. CONCLUSIONS: These data indicate that one of the effects of NSAIDs is to reduce HIF protein levels. The inhibition of HIFs by NSAIDs was COX-2 independent.

Anti-Inflammatory Agents, Non-Steroidal↗

Irradiation of tumor cells up-regulates Fas and enhances CTL lytic activity and CTL adoptive immunotherapy.

CD8(+) CTL play important roles against malignancy in both active and passive immunotherapy. Nonetheless, the success of antitumor CTL responses may be improved by additional therapeutic modalities. Radiotherapy, which has a long-standing use in treating neoplastic disease, has been found to induce unique biologic alterations in cancer cells affecting Fas gene expression, which, consequently, may influence the overall lytic efficiency of CTL. Here, in a mouse adenocarcinoma cell model, we examined whether exposure of these tumor cells to sublethal doses of irradiation 1) enhances Fas expression, leading to more efficient CTL killing via Fas-dependent mechanisms in vitro; and 2) improves antitumor activity in vivo by adoptive transfer of these Ag-specific CTL. Treatment of carcinoembryonic Ag-expressing MC38 adenocarcinoma cells with irradiation (20 Gy) in vitro enhanced Fas expression at molecular, phenotypic, and functional levels. Furthermore, irradiation sensitized these targets to Ag-specific CTL killing via the Fas/Fas ligand pathway. We examined the effect of localized irradiation of s.c. growing tumors on the efficiency of CTL adoptive immunotherapy. Irradiation caused up-regulation of Fas by these tumor cells in situ, based on immunohistochemistry. Moreover, localized irradiation of the tumor significantly potentiated tumor rejection by these carcinoembryonic Ag-specific CTL. Overall, these results showed for the first time that 1) regulation of the Fas pathway in tumor cells by irradiation plays an important role in their sensitization to Ag-specific CTL; and 2) a combination regimen of tumor-targeted irradiation and CTL promotes more effective antitumor responses in vivo, which may have implications for the combination of immunotherapy and radiation therapy.

Animals↗

A phase I trial of etanidazole and hyperfractionated radiotherapy in children with diffuse brainstem glioma.

PURPOSE: To determine the toxicity and maximum tolerated dose of etanidazole administered concurrently with hyperfractionated radiation therapy (HRT) for children with brainstem glioma. METHODS AND MATERIALS: Eighteen patients with brainstem glioma were treated with etanidazole and HRT on a dose escalation protocol (Phase I trial) between 1990 and 1996. All patients had MRI confirmation of diffuse pontine glioma and signs/symptoms of cranial nerve deficit, ataxia, or long tract signs of <6 months' duration. Cervicomedullary tumors were excluded. Patients (median age: 8.5 years; 11 males, 7 females) received HRT to the tumor volume plus a 2-cm margin with parallel-opposed 6-15-MV photons. The total dose was 66 Gy in 44 fractions (1.5 Gy b.i.d., with at least 6 h between fractions) for the first 3 patients and 63 Gy in 42 fractions for the subsequent 15 patients. Etanidazole was administered as a rapid i.v. infusion 30 min before the morning fraction of HRT. Planned doses of etanidazole were 1.8 g/m(2) x 17 doses (30.6 g/m(2)) at Step 1 to a maximum of 2.4 g/m(2) x 21 doses (50.4 g/m(2)) at Step 8. Dose escalation was planned with 3 patients at each of the 8 levels. RESULTS: Three patients were treated at each dose level except Level 2, on which only 1 patient was treated. The highest dose level achieved was Level 7, which delivered a total etanidazole dose of 46.2 g/m(2). Two patients were treated at this level, and both patients experienced Grade 3 toxicity in the form of a diffuse cutaneous rash. Three patients received a lower dose of 42 g/m(2) (dose Level 6) without significant toxicity, and this represents the maximum tolerated dose (MTD). There were 23 cases of Grade 1 toxicity (10 vomiting, 5 peripheral neuropathy, 2 rash, 2 constipation, 1 weight loss, 3 others), 11 cases of Grade 2 toxicity (4 vomiting, 2 skin erythema, 2 constipation, 1 arthralgia, 1 urinary retention, 1 hematologic), and 4 Grade 3 toxicities (2 rash, 1 vomiting, 1 skin desquamation). Grade 2 or 3 peripheral neuropathy was not seen at any dose level. The median survival from the start of treatment was 8.5 months (range: 3-58 months). CONCLUSION: The MTD of etanidazole in children receiving HRT for brainstem glioma is 42 g/m(2), with cutaneous rash as the dose-limiting toxicity. This is in contrast to the adult experience, which demonstrates a 24% lower MTD of 34 g/m(2) limited by peripheral neuropathy.

Adolescent↗

CTCAE v3.0: development of a comprehensive grading system for the adverse effects of cancer treatment.

Multiple systems have been developed for grading the adverse effects (AEs) of cancer treatment. The National Cancer Institute Common Toxicity Criteria (CTC) system has substantially evolved since its inception in 1983. The most recent version, CTCAE v3.0 (Common Terminology Criteria for Adverse Events version 3.0) represents the first comprehensive, multimodality grading system for reporting the acute and late effects of cancer treatment. The new CTC requires changes in the application of AE criteria including new guidelines regarding late effects, surgical and pediatric effects, multimodality issues, and for reporting the duration of an effect. It builds on the strengths of previous systems, represents a considerable effort among hundreds of participants, and signifies an international collaboration and consensus of the oncology research community. This article updates recent progress in the evolution of adverse effects grading systems and reviews the development of CTCAE v3.0.

Academies and Institutes↗

Effects of radiation on normal tissue: consequences and mechanisms.

The use of radiation therapy to treat cancer inevitably involves exposure of normal tissues. As a result, patients may experience symptoms associated with damage to normal tissue during the course of therapy for a few weeks after therapy or months or years later. Symptoms may be due to cell death or wound healing initiated within irradiated tissue, and may be precipitated by exposure to further injury or trauma. Many factors contribute to risk and severity of normal tissue reactions; these factors are site specific and vary with time after treatment. Treatments that reduce the risk or severity of damage to normal tissue or that facilitate the healing of radiation injury are being developed. These could greatly improve the quality of life of patients treated for cancer.

Animals↗

Linking radiation oncology and imaging through molecular biology (or now that therapy and diagnosis have separated, it's time to get together again!).

Among the areas defined by the National Cancer Institute as "Extraordinary Opportunities for Research Investment" that are highly relevant to the technology-oriented disciplines within the broad field of radiology are cancer imaging, defining the signatures (ie, underlying molecular features) of cancer cells, and molecular targets of prevention and treatment. In molecular target credentialing, a specific molecular target is imaged, the molecular signature is defined, a treatment is given, and the effect of the intervention on the image findings and the signature is then evaluated. Such an approach is used to validate the proposed target as a legitimate one for cancer therapy or prevention and to provide the opportunity to ultimately individualize therapy on the basis of both the initial characteristics of the tumor and the tumor's response to an intervention. Therapeutic radiation is focused biology (ie, radiation produces molecular events in the irradiated tissue). Radiation can (a) kill cancer cells by itself, (b) be combined with cytotoxic or cytostatic drugs, and (c) serve to initiate radiation-inducible molecular targets that are amenable to treatment with drugs and/or biologic therapies. Focused biology can be anatomically confined with various types of external beams and with brachytherapy, and it can be used systemically with targeted radioisotopes. These new paradigms link diagnostic imaging, radiation therapy, and nuclear medicine in unique ways by way of basic biology. It is timely to develop new collaborative research, training, and education agendas by building on one another's expertise and adopting new fields of microtechnology, nanotechnology, and mathematical analysis and optimization.

Combined Modality Therapy↗

Molecular and cellular biology of moderate-dose (1-10 Gy) radiation and potential mechanisms of radiation protection: report of a workshop at Bethesda, Maryland, December 17-18, 2001.

Exposures to doses of radiation of 1-10 Gy, defined in this workshop as moderate-dose radiation, may occur during the course of radiation therapy or as the result of radiation accidents or nuclear/radiological terrorism alone or in conjunction with bioterrorism. The resulting radiation injuries would be due to a series of molecular, cellular, tissue and whole-animal processes. To address the status of research on these issues, a broad-based workshop was convened. The specific recommendations were: (1) RESEARCH: Identify the key molecular, cellular and tissue pathways that lead from the initial molecular lesions to immediate and delayed injury. The latter is a chronic progressive process for which postexposure treatment may be possible. (2) Technology: Develop high-throughput technology for studying gene, protein and other biochemical expression after radiation exposure, and cytogenetic markers of radiation exposure employing rapid and accurate techniques for analyzing multiple samples. (3) Treatment strategies: Identify additional biological targets and develop effective treatments for radiation injury. (4) Ensuring sufficient expertise: Recruit and train investigators from such fields as radiation biology, cancer biology, molecular biology, cellular biology and wound healing, and encourage collaboration on interdisciplinary research on the mechanisms and treatment of radiation injury. Communicate knowledge of the effects of radiation exposure to the general public and to investigators, policy makers and agencies involved in response to nuclear accidents/events and protection/treatment of the general public.

Animals↗

Phase III study of ibuprofen versus placebo for radiation-induced genitourinary side effects.

PURPOSE: On the basis of our anecdotal clinical observations that nonsteroidal anti-inflammatory agents relieved dysuria during radiotherapy for patients with prostate cancer, we conducted a Phase III randomized trial of ibuprofen vs. placebo for patients who had an increase in acute urinary symptoms. Our in vitro and in vivo laboratory data with a higher concentration of ibuprofen than achievable in this study demonstrated radiosensitization. This study examined whether the inflammatory response within the prostate during radiotherapy would respond to the standard dose of ibuprofen as assessed by a symptom score. METHODS AND MATERIALS: Patients were registered to the study and were followed weekly with a formal symptom assessment. A double-blind randomization to ibuprofen, 400 mg q.i.d., vs. placebo for 7 days was done at a time when the severity score increased. The symptom response was evaluated at the end of the week. RESULTS: Between 1995 and 1998, 100 patients were entered, 28 did not have a sufficient change in symptom score to be randomized, and 19 were either unable to take ibuprofen or withdrew before randomization. Of the 53 patients randomized, 27 received placebo and 26 ibuprofen. No statistically significant differences were found between the placebo and ibuprofen groups between baseline and randomization or between randomization and the 1-week posttreatment assessment. Neither group had a change in symptom severity between randomization and the 1-week posttreatment evaluation. CONCLUSION: The standard anti-inflammatory dose of ibuprofen did not relieve the acute urinary or rectal symptoms during radiotherapy for prostate cancer. The nonsteroidal anti-inflammatory drugs are potential radiation sensitizers with the mechanism of action as yet unknown. Clinical trials of the cyclooxygenase inhibitors as radiation sensitizers should explore a range of doses and evaluate potential mechanisms of action, including cyclooxygenase inhibition and other non-cyclooxygenase mechanisms.

Aged↗

Radiation oncology--linking technology and biology in the treatment of cancer.

Technical advances in radiation oncology including CT-simulation, 3D- conformal and intensity-modulated radiation therapy (IMRT) delivery techniques, and brachytherapy have allowed greater treatment precision and dose escalation. The ability to intensify treatment requires the identification of the critical targets within the treatment field, recognizing the unique biology of tumor, stroma and normal tissue. Precision is technology based while accuracy is biologically based. Therefore, the intensity of IMRT will undoubtedly mean an increase in both irradiation dose and the use of biological agents, the latter considered in the broadest sense. Radiation oncology has the potential and the opportunity to provide major contributions to the linkage between molecular and functional imaging, molecular profiling and novel therapeutics for the emerging molecular targets for cancer treatment. This process of 'credentialing' of molecular targets will require multi disciplinary imaging teams, clinicians and basic scientists. Future advances will depend on the appropriate integration of biology into the training of residents, continuing post graduate education, participation in innovative clinical research and commitment to the support of basic research as an essential component of the practice of radiation oncology.

Biology↗

Low-grade follicular lymphoma of the small intestine.

BACKGROUND: Although the gastrointestinal tract is the most common site of extranodal non-Hodgkin's lymphoma (NHL), primary small intestine lymphomas remain relatively rare, especially localized low-grade follicular B-cell lymphomas. When lymphomas do occur at this site, most are high grade and require aggressive therapy. We report three cases of small intestinal follicular lymphoma diagnosed on endoscopic biopsy and review the clinical history, pathologic features, and treatment outcome. STUDY: A review of the medical records and pathology from three cases of small intestine follicular NHL was performed. The pathology specimens were formalin-fixed, paraffin-embedded tissues processed for routine microscopic examination, immunohistochemical staining, and molecular analysis. RESULTS: Histologic and immunophenotypical studies were diagnostic of grade 1 follicular lymphoma (Revised European-American Lymphoma classification/World Health Organization classification). All cases expressed bcl-2 protein, and polymerase chain reaction analysis supported the diagnosis in two cases with adequate DNA. With 23.3 months' median follow-up, one untreated and one treated patient were alive without symptoms; a third untreated patient died of a nonlymphoma cause. CONCLUSION: Isolated indolent lymphomas of the small intestine are rare. Accurate pathologic staging and histologic classification are paramount in delineating treatment options.

Aged↗

Modifying normal tissue damage postirradiation. Report of a workshop sponsored by the Radiation Research Program, National Cancer Institute, Bethesda, Maryland, September 6-8, 2000.

Late effects that develop in normal tissues adjacent to the tumor site in the months to years after radiotherapy can reduce the quality of life of cancer survivors. They can be dose-limiting and debilitating or life-threatening. There is now evidence that some late effects may be preventable or partially reversible. A workshop, "Modifying Normal Tissue Damage Postirradiation", was sponsored by the Radiation Research Program of the National Cancer Institute to identify the current status of and research needs and opportunities in this area. Mechanistic, genetic and physiological studies of the development of late effects are needed and will provide a rational basis for development of treatments. Interdisciplinary teams will be needed to carry out this research, including pathologists, physiologists, geneticists, molecular biologists, experts in functional imaging, wound healing, burn injury, molecular biology, and medical oncology, in addition to radiation biologists, physicists and oncologists. The participants emphasized the need for developing and choosing appropriate models, and for radiation dose-response studies to determine whether interventions remain effective at the radiation doses used clinically. Both preclinical and clinical studies require long-term follow-up, and easier-to-use, more objective clinical scoring systems must be developed and standardized. New developments in biomedical imaging should provide useful tools in all these endeavors. The ultimate goals are to improve the quality of life and efficacy of treatment for cancer patients treated with radiotherapy.

Animals↗