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981.
We used whole-exome and targeted sequencing to characterize somatic mutations in 103 colorectal cancers (CRC) from African Americans, identifying 20 new genes as significantly mutated in CRC. Resequencing 129 Caucasian derived CRCs confirmed a 15-gene set as a preferential target for mutations in African American CRCs. Two predominant genes, ephrin type A receptor 6 (EPHA6) and folliculin (FLCN), with mutations exclusive to African American CRCs, are by genetic and biological criteria highly likely African American CRC driver genes. These previously unsuspected differences in the mutational landscapes of CRCs arising among individuals of different ethnicities have potential to impact on broader disparities in cancer behaviors.Colorectal cancer (CRC) is a leading cause of cancer mortality world-wide. CRC incidence and mortality rates are both increased in African Americans (AA) compared with Caucasians Americans (13). Although several factors likely play a role, the contribution of potential differences in tumor genetics to this disparity have yet to be fully explored (1, 3). In particular, AA CRCs were notably underrepresented in the four major published CRC sequencing studies (47), accounting for only two annotated AA cases of the 333 total CRCs studied (47). Accordingly, we initiated this study to compare the mutational landscapes of CRCs from AA individuals versus Caucasians.  相似文献   
982.
On September 11, 2014, a workshop entitled ‘Advanced Therapy Medicinal Products: How to Bring Cell-Based Medicinal Product Successfully to the Market’ was held at the 47th annual meeting of the German Society for Transfusion Medicine and Immunohematology (DGTI), co-organised by the European Medicines Agency (EMA) and the DGTI in collaboration with the German Stem Cell Network (GSCN). The workshop brought together over 160 participants from academia, hospitals, small- or medium-sized enterprise developers and regulators. At the workshop, speakers from EMA, the Committee for Advanced Therapies (CAT), industry and academia addressed the regulatory aspects of development and authorisation of advanced therapy medicinal products (ATMPs), classification of ATMPs and considerations on cell-based therapies for cardiac repair. The open forum discussion session allowed for a direct interaction between ATMP developers and the speakers from EMA and CAT.Key Words: Advanced therapy medicinal products, ATMP, Committee for Advanced Therapies, CAT  相似文献   
983.
The role of cigarette smoking and diabetes mellitus as risk factors for exocrine pancreatic cancer (PC) was investigated in a hospital based case-control study. Current smokers were at increased risk for PC (OR = 2.36, 95% CI 1.53-3.63): the magnitude of the risk was related to the lifetime amount of smoking (chi2(trend) = 17.00; P < 0.0001). Among former smokers, after 15 years from ceasing smoking, the risk for PC dropped to the level of a lifetime non-smoker, whichever the lifetime smoking amount. Diabetes was associated with a 2.89-fold increased risk for PC (95% CI 1.71-4.86): the risk was 4.76 (95% CI 1.99-11.53) for diabetes diagnosed up to 2 years before the diagnosis of PC and dropped to 2.07 (95% CI 1.02-4.20) for diabetes diagnosed more than 5 years before PC. The risk for PC was estimated according to the treatment used to control diabetes: it was 6.49 (95% CI 2.28-18.48) for insulin treated diabetes and 2.12 (95% CI 1.16-3.87) for diabetes treated with oral hypoglycemic drugs. The risk of PC for diabetes treated for more than 5 years before the diagnosis of PC was 6.21 (95% CI 1.61-23.96) for patients treated with insulin and 1.21 (95% CI 0.50-2.92) for those treated with oral hypoglycemic drugs: the type of treatment needed to control the disease may discriminate between the diabetes that represents a consequence of cancer from the diabetes that could represent an etiological co-factor. More studies are needed to clarify whether long-lasting insulin-treated diabetes is an etiological co-factor in PC.  相似文献   
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988.
Prostate cancer, and in particular the management options for patients with metastatic castration‐resistant prostate cancer (mCRPC), remains an important health issue. The approval of cabazitaxel provides a new treatment option for patients who have progressed despite docetaxel therapy. Clinical use of cabazitaxel in mCRPC is based on the results of the TROPIC study, which demonstrated an approximately 30% reduction in the risk of death compared with mitoxantrone. In this paper, we draw on accumulating clinical experience with cabazitaxel in Australia to discuss important questions such as how to select the right patient for treatment and how to proactively prevent and manage toxicities associated with this therapy. Recognizing the need for a multidisciplinary approach to patient care, opinion and insight has been sought from medical oncologists, nurses and pharmacists. While lack of trial data means that a number of questions remain unanswered, local clinical experience has helped to guide treatment decisions and refine management protocols. Appropriate patient selection, careful ongoing monitoring and proactive management of adverse events will ensure optimal treatment of patients. Nurses in particular play an important role in educating patients and identifying patients at increased risk of developing adverse events with cabazitaxel. The oncology team must work together to educate patients; taking a proactive approach to issues such as adverse events will help maximize the clinical outcome of cabazitaxel treatment and impact positively on the patient's quality of life.  相似文献   
989.
Breast cancer is one of the leading causes of cancer death among women in the United States. Patients expressing the estrogen and progesterone receptor (ER and PR) and human epidermal growth factor 2 (HER-2) tumor markers have favorable prognosis and efficacious therapeutic options. In contrast, tumors that are negative for these markers (triple-negative) have a disproportionate share of morbidity and mortality due to lack of a validated molecular target.Deubiquitinating enzymes (DUBs) are a critical component of ubiquitin-proteasome-system degradation and have been shown to be differentially expressed and activated in a number of cancers, including breast, with their aberrant activity linked to cancer prognosis and clinical outcome. We evaluated the effect of the DUB inhibitors b-AP15 and RA-9 alone and in combination with early- and late-stage lysosomal inhibitors on cell viability in a panel of triple negative breast cancer (TNBC) cell lines.Our results indicate small-molecule DUB inhibitors have a profound effect on TNBC viability and lead to activation of autophagy as a cellular mechanism to compensate for ubiquitin-proteasome-system stress. Treatment with sub-optimal doses of DUB and lysosome inhibitors synergistically kills TNBC cells. This supports the evaluation of DUB inhibition, in combination with lysosomal inhibition, as a therapeutic approach for the treatment of TNBC.  相似文献   
990.

Background/aims

Pancreatic cancer (PC) is ranked as the fourth leading cause of cancer-related deaths worldwide. Despite recent advances in treatment options, a modest impact on the outcome of the disease is observed so far. Short-term fasting cycles have been shown to potentiate the efficacy of chemotherapy against glioma. The aim of this study was to assess the effect of fasting cycles on the efficacy of gemcitabine, a standard treatment for PC patients, in vitro and in an in vivo pancreatic cancer mouse xenograft model.

Materials and Methods

BxPC-3, MiaPaca-2 and Panc-1 cells were cultured in standard and fasting mimicking culturing condition to evaluate the effects of gemcitabine. Pancreatic cancer xenograft mice were subjected to 24h starvation prior to gemcitabine injection to assess the tumor volume and weight as compared to mice fed ad libitum.

Results

Fasted pancreatic cancer cells showed increased levels of equilibrative nucleoside transporter (hENT1), the transporter of gemcitabine across the cell membrane, and decreased ribonucleotide reductase M1 (RRM1) levels as compared to those cultured in standard medium. Gemcitabine was more effective in inducing cell death on fasted cells as compared to controls. Consistently, xenograft pancreatic cancer mice subjected to fasting cycles prior to gemcitabine injection displayed a decrease of more than 40% in tumor growth.

Conclusion

Fasting cycles enhance gemcitabine effect in vitro and in the in vivo PC xenograft mouse model. These results suggest that restrictive dietary interventions could enhance the efficacy of existing cancer treatments in pancreatic cancer patients.  相似文献   
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