Prognostic and Predictive Biomarkers in Head and Neck Squamous Cell Carcinoma Treated with Radiotherapy—A Systematic Review

Background: Radiotherapy is a mainstay in head and neck squamous cell carcinoma (HNSCC) treatment but is mostly applied without stratification by molecular diagnostics. Development of reliable biomarkers may have the potential to improve radiotherapy (RT) efficacy and reduce toxicity. We conducted a systematic review to summarize the field of biomarkers in HNSCC treated by RT. Methods: Pubmed and EMBASE were searched independently by two researchers following pre-defined inclusion and exclusion criteria. Z curves were generated to investigate publication bias. OncoKB was used for identification of druggable targets. Results: 134 manuscripts remained for data extraction. 12% of tumors were AJCC/UICC stage I–II and 82% were stage III–IV. The most common biomarkers were proteins (39%), DNA (14%) and mRNA (9%). Limiting analysis to prospective data and statistically significant results, we found three potentially druggable targets: ERCC2, PTCH1 and EGFR. Regarding data quality, AJCC/UICC stage was missing in 32% of manuscripts. 73% of studies were retrospective and only 7% were based on prospective randomized trials. Z-curves indicated the presence of publication bias. Conclusion: An abundance of potential biomarkers in HNSCC is available but data quality is limited by retrospective collection, lack of validation and publication bias. Improved study design and reporting quality might accelerate successful development of personalized treatments in HNSCC

Differential inhibition sensitivities of MET mutants to the small molecule inhibitor SU11274

Point mutations emerge as one of the rate-limiting steps in tumor response to small molecule inhibitors of protein kinases. Here we characterized the response of the MET mutated variants, V1110I, V1238I, V1206L and H1112L to the small molecule SU11274. Our results reveal a distinct inhibition pattern of the four mutations with IC(50) values for autophosphorylation inhibition ranging between 0.15 and 1.5muM. Differences were further seen on the ability of SU11274 to inhibit phosphorylation of downstream MET transducers such as AKT, ERK, PLCgamma and STAT3 and a variety of MET-dependent biological endpoints. In all the assays, H1112L was the most sensitive to SU11274, while V1206L was less affected under the used concentration range. The differences in responses to SU11274 are discussed based on a structural model of the MET kinase domain

Coupling of mutated Met variants to DNA repair via Abl and Rad51

Abnormal activation of DNA repair pathways by deregulated signaling of receptor tyrosine kinase systems is a compelling likelihood with significant implications in both cancer biology and treatment. Here, we show that due to a potential substrate switch, mutated variants of the receptor for hepatocyte growth factor Met, but not the wild-type form of the receptor, directly couple to the Abl tyrosine kinase and the Rad51 recombinase, two key signaling elements of homologous recombination-based DNA repair. Treatment of cells that express the mutated receptor variants with the Met inhibitor SU11274 leads, in a mutant-dependent manner, to a reduction of tyrosine phosphorylated levels of Abl and Rad51, impairs radiation-induced nuclear translocation of Rad51, and acts as a radiosensitizer together with the p53 inhibitor pifithrin-alpha by increasing cellular double-strand DNA break levels following exposure to ionizing radiation. Finally, we propose that in order to overcome a mutation-dependent resistance to SU11274, this aberrant molecular axis may alternatively be targeted with the Abl inhibitor, nilotinib

Cortisol/cortisone Ratio in Sows during Heart Intervention The Cortisol to Cortisone Ratio during Cardiac Catheterisation in Sows

Abstract: A possible effect of mini-invasive heart intervention on a response of hypothalamo-pituitary-adrenal stress axis and conversion of cortisone to cortisol were studied. We have analysed two stress markers levels (cortisol, cortisone) and cortisol/cortisone ratio in 25 sows using minimally invasive heart catheterisation as the stress factor. The values of studied parameters were assessed in four periods of the experiment: (1) the baseline level on the day before intervention, (2) after the introduction of anaesthesia, (3) after conducting tissue stimulation or ablation, and (4) after the end of the catheterisation. For statistical analyses we used the nonparametric Friedman test for four dependent samples (including all four stages of the operation) or three dependent samples (influence of operation only, baseline level was excluded). Statistically significant differences in both Friedman tests were found for cortisol and for cortisone. We have found the highest level of cortisol/ cortisone ratio in unstressed conditions, then it decreased to the minimal level at http://d