In our work with designed minimalist proteins based on the bZIP motif, we have found our Histagged proteins to be prone to inclusion body formation and aggregation; we suspect this problem is largely due to the His tag, known to promote aggregation. Using AhR6-C/EBP, a hybrid of the AhR basic region and C/EBP leucine zipper, as representative of our bZIP-like protein family, we attempted removal of the His tag with enterokinase (EK) but obtained the desired cleavage product in very small yield. EK is known for proteolysis at noncanonical sites, and most cleavage occurred at unintended sites. We manipulated experimental conditions to improve specificity of proteolysis and analyzed the cleavage products; no effect was observed after changing pH, temperature, or the amount of EK. We then suspected the accessibility of the EK site was impeded due to protein aggregation. We found that the easily implemented strategy of addition of urea (1-4 M) greatly improved EK cleavage specificity at the canonical site and reduced adventitious cleavage. We believe that this enhancement in specificity is due to a more "open" protein structure, in which the now accessible canonical target can compete effectively with adventitious cleavage sites of related sequence.

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BackgroundThe efficacy of carboplatin-paclitaxel in the trimodality setting was demonstrated in the cross

Background Older patients are commonly excluded from clinical trials in esophageal and gastroesophageal

High-quality studies reporting adjusted hazard ratios are associated with improved survival in patients receiving radiotherapy for STS. Studies in which odds ratios are calculated from event data and those that do not report adjusted outcomes do not show the same association, likely due to confounding by indication.

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Introduction: The ability to predict lymph node (LN) status is essential in the management of men with localized squamous cell carcinoma (SCC) of the penis. There has been limited external validation of available risk stratification tools, particularly in routine clinical care. The objective of this study was to evaluate the predictive variables of LN metastases within a large population-based cohort of patients. Methods: In this population-based cohort study, surgical pathology reports were linked to the population-based Ontario Cancer Registry to identify all patients who were diagnosed with penile cancer in Ontario, Canada. Multivariable analyses were performed to evaluate predictive variables for LN involvement. Three contemporary risk stratification schemes used to predict LN status were analyzed by logistic regression. Results: The study included 380 localized penile SCC cases treated between 2000 and 2010. Sixty-three (17%) had pathologically confirmed LN metastases. Among these, 35 (56%) were diagnosed within three months of the initial penile SCC diagnosis and these patients had a worse five-year disease-specific survival (43%; 95% confidence interval [CI] 26-64) compared to patients who were diagnosed at a delayed LN dissection. On multivariable analysis, age (odds ratio [OR] 0.68; 95% CI 0.52-0.88), pathological stage (≥pT1b; OR 3.32; 95% CI 1.38-8.01), and tumour grade (Grade 2 OR 2.98; 95% CI 1.26-7.62; Grade 3 OR 3.97; 95% CI 1.32-11.9) were associated with an increased risk of LN metastases. Candidate risk stratification schemes demonstrated moderate to good property, with c-statistics ranging from 0.662-0.747.

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