Gemcitabine/cisplatin versus 5-fluorouracil/mitomycin C chemoradiotherapy in locally advanced pancreatic cancer: a retrospective analysis of 93 patients

Deep-Penetrating Triple-Responsive Prodrug Nanosensitizer Actuates Efficient Chemoradiotherapy in Pancreatic Ductal Adenocarcinoma Models

Chemoradiotherapy (CRT) is the most accepted treatment for locally advanced pancreatic ductal adenocarcinoma (PDAC) and can significantly improve the R0 resection rate. However, there are few long-term survivors after CRT. Although some polymer nanoparticles have shown potential in alleviating the dose-limiting toxicity and assisting the chemotherapy of PDAC, there are few efficient nanosensitizers (NS) available for CRT of this malignancy, especially in the context of its hypoxic nature. Herein, based on the biological features of PDAC, a γ-glutamyl transpeptidase (GGT)/glutathione (GSH)/hypoxia triple-responsive prodrug NS to overcome the biological barrier and microenvironmental limitations confronted by CRT in PDAC is developed. Due to triple-responsiveness, deep tumor penetration, GSH/hypoxia-responsive drug release/activation, and hypoxia-induced chemoradio-sensitization can be simultaneously achieved with this NS. As a result, tumor shrinkage after CRT with this NS can be observed in both subcutaneous and orthotopic PDAC models, foreshadowing its potential in clinical neoadjuvant CRT.

Clinical therapies and nano drug delivery systems for urinary bladder cancer

Bladder cancer is the 10^th most commonly occurring malignancy worldwide with a 75% of 5-year survival rate, while it ranks 13^th among the deaths occurring due to cancer. The majority of bladder cancer cases are diagnosed at an early stage and 70% are of non-invasive grade. However, 70% of these cases develop chemoresistance and progress to the muscle invasive stage. Conventional chemotherapy treatments are unsuccessful in curbing chemoresistance, bladder cancer progression while having an adverse side effect, which is mainly due to off-target drug distribution. Therefore, new drug delivery strategies, new therapeutics and therapies or their combination are being explored to develop better treatments. In this regard, nanotechnology has shown promise in the targeted delivery of therapeutics to bladder cancer cells. This review discusses the recent discovery of new therapeutics (chemotherapeutics, immunotherapeutic, and gene therapies), recent developments in the delivery of therapeutics using nano drug delivery systems, and the combination treatments with FDA-approved therapies, i.e., hyperthermia and photodynamic therapy. We also discussed the potential of other novel drug delivery systems that are minimally explored in bladder cancer. Lastly, we discussed the clinical status of therapeutics and therapies for bladder cancer. Overall, this review can provide a summary of available treatments for bladder cancer, and also provide opportunities for further development of drug delivery systems for better management of bladder cancer.

Feasibility analysis of conducting observational studies with the electronic health record

Background

The secondary use of electronic health records (EHRs) promises to facilitate medical research. We reviewed general data requirements in observational studies and analyzed the feasibility of conducting observational studies with structured EHR data, in particular diagnosis and procedure codes.

Methods

After reviewing published observational studies from the University Hospital of Erlangen for general data requirements, we identified three different study populations for the feasibility analysis with eligibility criteria from three exemplary observational studies. For each study population, we evaluated the availability of relevant patient characteristics in our EHR, including outcome and exposure variables. To assess data quality, we computed distributions of relevant patient characteristics from the available structured EHR data and compared them to those of the original studies. We implemented computed phenotypes for patient characteristics where necessary. In random samples, we evaluated how well structured patient characteristics agreed with a gold standard from manually interpreted free texts. We categorized our findings using the four data quality dimensions “completeness”, “correctness”, “currency” and “granularity”.

Results

Reviewing general data requirements, we found that some investigators supplement routine data with questionnaires, interviews and follow-up examinations. We included 847 subjects in the feasibility analysis (Study 1 n = 411, Study 2 n = 423, Study 3 n = 13). All eligibility criteria from two studies were available in structured data, while one study required computed phenotypes in eligibility criteria. In one study, we found that all necessary patient characteristics were documented at least once in either structured or unstructured data. In another study, all exposure and outcome variables were available in structured data, while in the other one unstructured data had to be consulted. The comparison of patient characteristics distributions, as computed from structured data, with those from the original study yielded similar distributions as well as indications of underreporting. We observed violations in all four data quality dimensions.

Conclusions

While we found relevant patient characteristics available in structured EHR data, data quality problems may entail that it remains a case-by-case decision whether diagnosis and procedure codes are sufficient to underpin observational studies. Free-text data or subsequently supplementary study data may be important to complement a comprehensive patient history.

Gemcitabine Conjugated Chitosan and Double Antibodies (Abc-GC-Gemcitabine Nanoparticles) Enhanced Cytoplasmic Uptake of Gemcitabine and Inhibit Proliferation and Metastasis In Human SW1990 Pancreatic Cancer Cells

BACKGROUND Pancreatic cancer is considered a chemoresistant neoplasm with extremely dismal prognosis and gemcitabine treatment is associated with many side effects and poor overall survival. The study aimed at developing a new nanobioconjugate, which specifically delivered gemcitabine and anti-EGFR antibody into pancreatic cancer cells. MATERIAL AND METHODS The novel nanodrug is based on chitosan platform, which is non-toxic, biocompatibility and biodegradable. We measured the effects of proliferation and metastasis on SW1990 by CCK-8 assay, colony formation assay, wound healing assay and Transwell assay. The expression of related proteins were evaluated by Western blot. RESULTS We synthesized Abc-GC-gemcitabine nanoparticles successfully with the encapsulation rate of nanobioconjugates was 91.63% and the drug loadings was 9.97%. Both GC-gemcitabine microspheres solution (GC group) and Abc-GC-gemcitabine microspheres solution (Abc group) inhibited cells proliferation, colony formation, migration and invasion in SW1990 cells dramatically. Moreover, Abc-GC-gemcitabine microspheres expressed more significant inhibited action than GC-gemcitabine microspheres efficiently CONCLUSIONS Our data suggested that Abc-GC-gemcitabine nanoparticles could have promising potential in treating metastasized and chemoresistant pancreatic cancer by enhancing the drug efficacy and minimizing off target effects.

Modeling Combined Chemotherapy and Particle Therapy for Locally Advanced Pancreatic Cancer

Pancreatic ductal adenocarcinoma is the only cancer for which deaths are predicted to increase in 2014 and beyond. Combined radiochemotherapy protocols using gemcitabine and hypofractionated X-rays are ongoing in several clinical trials. Recent results indicate that charged particle therapy substantially increases local control of resectable and unresectable pancreas cancer, as predicted from previous radiobiology studies considering the high tumor hypoxia. Combination with chemotherapy improves the overall survival (OS). We compared published data on X-ray and charged particle clinical results with or without adjuvant chemotherapy calculating the biological effective dose. We show that chemoradiotherapy with protons or carbon ions results in 1 year OS significantly higher than those obtained with other treatment schedules. Further hypofractionation using charged particles may result in improved local control and survival. A comparative clinical trial using the standard X-ray scheme vs. the best current standard with carbon ions is crucial and may open new opportunities for this deadly disease.

Dihydromyricetin Enhances the Chemo-Sensitivity of Nedaplatin via Regulation of the p53/Bcl-2 Pathway in Hepatocellular Carcinoma Cells

Chemotherapy is an effective weapon in the battle against cancer. Nedaplatin (NDP) is an improved platinum-containing drug with lower cytotoxicity than other similar drugs. However, the repeated use of NDP results in substantial hepatocyte damage as well as drug resistance in hepatocellular carcinoma (HCC) cases. Therefore, the development of effective chemotherapy strategies that enhance tumor sensitivity to chemotherapeutics and reduce the secondary damage to liver cells is urgently needed. Dihydromyricetin (DHM), a natural flavonoid compound, has been shown to have antitumor activity with no obvious toxicity to normal cells in vitro and in vivo. In this study, DHM and NDP were combined to treat liver cancer cells; we found that DHM functions as a protector of normal cells compared with the use of NDP alone. In addition, the synergy of DHM with NDP enhanced the effect of NDP on the induction of HCC cell apoptosis. We found that the combination caused clear changes in the level of reactive oxygen species (ROS). Furthermore, we demonstrated that the combination of DHM and NDP activated the p53/Bcl-2 signaling pathway, which resulted in mitochondrial dysfunction and induced cell death and growth inhibition in HCC cells.

Genetic determinants and potential therapeutic targets for pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer deaths in both men and women in the United States, carrying a 5-year survival rate of approximately 5%, which is the poorest prognosis of any solid tumor type. Given the dismal prognosis associated with PDAC, a more thorough understanding of risk factors and genetic predisposition has important implications not only for cancer prevention, but also for screening techniques and the development of personalized therapies. While screening of the general population is not recommended or practicable with current diagnostic methods, studies are ongoing to evaluate its usefulness in people with at least 5- to 10-fold increased risk of PDAC. In order to help identify high-risk populations who would be most likely to benefit from early detection screening tests for pancreatic cancer, discovery of additional pancreatic cancer susceptibility genes is crucial. Thus, specific gene-based, gene-product, and marker-based testing for the early detection of pancreatic cancer are currently being developed, with the potential for these to be useful as potential therapeutic targets as well. The goal of this review is to provide an overview of the genetic basis for PDAC with a focus on germline and familial determinants. A discussion of potential therapeutic targets and future directions in screening and treatment is also provided.