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Indiana University-Purdue University Indianapolis (IUPUI) / Patients with the genetic disorder tuberous sclerosis complex (TSC) suffer from neoplastic growths in multiple organ systems. These growths are the result of inactivating mutations in either the TSC1 or TSC2 tumor suppressor genes, which negatively regulate the activity of mammalian target of rapamycin complex 1(mTORC1). There is currently no cure for this disease; however, my research has found that cells harboring TSC2-inactivating mutations derived from a rat model of TSC are sensitive to apoptosis induced by the clinically approved proteasome inhibitor, bortezomib, in a manner dependent on their high levels of mTORC1 activation. We see that bortezomib induces the unfolded protein response (UPR) in our cell model of TSC, resulting in cell death via apoptosis. The UPR is induced by accumulation of unfolded protein in the endoplasmic reticulum (ER) which activates the three branches of this pathway: Activating transcription factor 6 (ATF6) cleavage, phosphorylation of eukaryotic initiation factor 2α (eIF2α), and the splicing of X-box binding protein1 (XBP1) mRNA. Phosphorylation of eIF2α leads to global inhibition of protein synthesis, preventing more unfolded protein from accumulating in the ER. This phosphorylation also induces the transcription and translation of ATF4 and CCAAT-enhancer binding protein homologous protein (CHOP). Blocking mTORC1 activity in these cells using the mTORC1 inhibitor, rapamycin, prevented the expression of ATF4 and CHOP at both the mRNA and protein level during bortezomib treatment. Rapamycin treatment also reduced apoptosis induced by bortezomib; however, it did not affect bortezomib-induced eIF2α phosphorylation or ATF6 cleavage. These data indicate that rapamycin can repress the induction of UPR-dependent apoptosis by suppressing the transcription of ATF4 and CHOP mRNAs. In addition to these findings, we find that a TSC2-null angiomyolipoma cell line forms vacuoles when treated with the proteasome inhibitor MG-132. We found these vacuoles to be derived from the ER and that rapamycin blocked their formation. Rapamycin also enhanced expansion of the ER during MG-132 stress and restored its degradation by autophagy. Taken together these findings suggest that bortezomib might be used to treat neoplastic growths associated with TSC. However, they also caution against combining specific cell death inducing agents with rapamycin during chemotherapy.

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No / Tea catechin epigallocatechin-3-gallate (EGCG) and other polyphenols, such as theaflavins (TFs), are increasingly proving useful as chemopreventives in a number of human cancers. They can also affect normal cells. The polyphenols in tea are known to have antioxidant properties that can quench free radical species, and pro-oxidant activities that appear to be responsible for the induction of apoptosis in tumor cells. The bioavailability of these natural compounds is an important factor that determines their efficacy. Nanoparticle (NP)-mediated delivery techniques of EGCG and TFs have been found to improve their bioavailability to a level that could benefit their effectiveness as chemopreventives. AIM: The present study was conducted to compare the effects of TFs and EGCG, when used in the bulk form and in the polymer (poly[lactic-co-glycolic acid])-based NP form, in oxaliplatin- and satraplatin-treated lymphocytes as surrogate cells from colorectal cancer patients and healthy volunteers. NPs were examined for their size distribution, surface morphology, entrapment efficiency and release profile. Lymphocytes were treated in the Comet assay with oxaliplatin and satraplatin, washed and treated with bulk or NP forms of tea phenols, washed and then treated with hydrogen peroxide to determine single-strand breaks after crosslinking. The results of DNA damage measurements by the Comet assay revealed opposite trends in bulk and NP forms of TFs, as well as EGCG. Both the compounds in the bulk form produced statistically significant concentration-dependent reductions in DNA damage in oxaliplatin- or satraplatin-treated lymphocytes. In contrast, when used in the NP form both TFs and EGCG, although initially causing a reduction, produced a concentration-dependent statistically significant increase in DNA damage in the lymphocytes. These observations support the notion that TFs and EGCG act as both antioxidants and pro-oxidants, depending on the form in which they are administered under the conditions of investigation.

No / PURPOSE/OBJECTIVES: To assess and improve the safety of hospital-based adult chemotherapy administration. DESIGN: Prospective, systems-focused clinical risk assessment. SETTING: An adult inpatient and outpatient oncology unit in a large urban hospital in the United Kingdom. SAMPLE: 8-person nurse-led multidisciplinary team, which included managerial staff and patient safety researchers. METHODS: Failure mode and effects analysis (FMEA), a prospective, systems-focused risk assessment methodology, was undertaken in biweekly team meetings and included mapping the chemotherapy administration process, identifying and numerically prioritizing potential errors (failure modes) for each process step, and generating remedial strategies to counteract them. MAIN RESEARCH VARIABLES: The analysis aimed to identify chemotherapy administration failure modes and to generate remedial strategies to address them. User feedback on the FMEA process also was collected. FINDINGS: Several specific chemotherapy failure modes were identified, the majority of which had not previously been recognized, and several novel strategies to counteract them were generated. Many of the strategies were specific, environment-focused actions, which are simple, quick, and inexpensive to implement; however, more substantive, longer-term initiatives also were generated. User feedback generally was very positive, and the process of undertaking the analysis improved multidisciplinary teamwork and communication. CONCLUSIONS: Although time and resource intensive, FMEA is a useful safety improvement tool. IMPLICATIONS FOR NURSING: Nurses should be aware of and informed about FMEA as a tool they can use in partnership with management and other disciplines to proactively and collectively improve the safety of high-risk oncology procedures such as chemotherapy administration.

Thesis (Ph. D.)--University of Virginia, 2008. / Includes bibliographical references. Also available online through Digital Dissertations.

A toxicidade vestibular pode ser definida como danos que uma substância química causa sobre a estrutura e a função vestibular. Entre as drogas que podem causar a vestibulotoxicidade estão os agentes antineoplásicos como os derivados da platina. OBJETIVO: Identificar a frequência de ocorrência de alteração vestibular em pacientes oncológicos tratados com derivados da platina, os sinais e sintomas vestibulares nestes pacientes, e se a alteração vestibular pré-existente exacerba os sintomas eméticos durante a quimioterapia com derivados da platina. METODOLOGIA: Amostra foi composta por pacientes adultos com câncer que realizaram tratamento com drogas derivadas da platina. O protocolo para o monitoramento vestibular foi composto pelo questionário Dizziness Handicap Inventory (DHI) Brasileiro, Testes da Função Vestibular (manobra de Dix-Hallpike e vecto-eletronistagmografia) e pela descrição de sintomas eméticos e tontura durante a quimioterapia e avaliação vestibular. RESULTADOS: Quarenta e oito pacientes realizaram a avaliação vestibular pré-quimioterapia, sendo que 23 (48%) apresentaram avaliação vestibular dentro da normalidade. Dezesseis pacientes submeteram-se ao monitoramento vestibular com avaliação antes e após tratamento, sendo que após o tratamento dois pacientes (12,5%) apresentaram avaliação vestibular dentro da normalidade e 14 (87,5%) apresentaram algum tipo de alteração vestibular, evidenciada somente pela prova calórica. Nenhum paciente referiu queixas vestibulares ao DHI na avaliação pré-tratamento, assim como quase todos os pacientes, exceto um, na avaliação pós tratamento. Apenas um (6,3%) com avaliação vestibular alterada pós-tratamento apresentou grau leve no DHI. A dose de cisplatina entre os pacientes que mostraram piora do quadro vestibular variou entre 160 e 400 mg/m² e dois pacientes foram tratados com carboplatina com dose de 2306 mg/m² e 1801 mg/m². Não houve diferença de manifestação dos sintomas eméticos/tontura durante a avaliação vestibular ou após quimioterapia entre os pacientes com e sem alteração vestibular prévia. Entretanto, os pacientes que referiram sintomas eméticos durante os ciclos de quimioterapia foram aqueles que manifestaram maior desconforto na PC, independente da dose de quimioterapia ou da alteração vestibular. CONCLUSÃO: Alteração vestibular ou a modificação do quadro vestibular ocorreu em 50% dos pacientes com câncer tratados com derivados da platina. O sinal mais frequente de alteração nos testes vestibulares foi a hiporreflexia à prova calórica, sem sintomas vestibulares relatados na vida diária destes pacientes. As alterações vestibulares pré-existentes não exacerbaram os sintomas eméticos durante a quimioterapia / Vestibular toxicity may be defined as a damage that chemical substances cause on the structure and the function of the vestibular system. Among the drugs that may cause vestibulotoxicity there are antineoplastic agents, such as those derived from platinum. OBJECTIVE: To identify the frequency of occurrence of vestibular alterations in cancer patients treated with platinum-based chemotherapy; the vestibular signs and symptoms in these patients, and whether the pre-existing vestibular alterations exacerbate emetic symptoms during chemotherapy with platinum-based drugs. METHODS: The sample was composed of adults who were treated of the cancer with platinum-based chemotherapy. The vestibular monitoring protocol involved the Brazilian Dizziness Handicap Inventory (DHI), Vestibular Function Tests (positioning nystagmus with Dix-Hallpike maneuver and vectoelectronystagmography) and the description of emetic symptoms and dizziness during chemotherapy and vestibular evaluation. RESULTS: Forty-eight subjects performed the pre-treatment vestibular evaluation, and 23 of them (48%) presented vestibular assessment within the normal range. Sixteen patients underwent the vestibular monitoring evaluation before and after treatment: after the treatment two patients (12.5%) showed normal vestibular assessment while 14 (87.5%) showed a vestibular disorder, basically in the caloric tests, but the alteration was considered a modification in their baseline stage in eight patients (50%). None of the patients reported complaints in the pre-treatment assessment, with a DHI scores within the normal range, as well as all the patients, except one, in the post treatment assessment (81,3%). Only one patient (6.3%) had a score above normal (mild complaint) with altered vestibular evaluation in the post treatment assessment. The dose of cisplatin among these patients who had a modification in the vestibular function varied from 160 to 400 mg/m² and two patients were treated with carboplatin with do of 2306 mg/m² and 1801 mg/m². There was no difference of emetic symptoms/dizziness during the chemotherapy or the vestibular evaluation among patients with or without previous vestibular alterations. However, patients who reported more emetic symptoms during chemotherapy cycles were those who showed greater discomfort in the caloric test, regardless of the dosage of chemotherapy or vestibular alteration. CONCLUSION: Vestibular alterations or modification of the baseline alteration were found in 50% of cancer patients treated with platinum-based chemotherapy. The most common sign of vestibular alteration in the vestibular tests was the hiporeflexia at the caloric test with no reported symptoms in their daily life. The preexisting vestibular alterations did not exacerbate emetic symptoms during chemotherapy