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Anilkumar, A.

Publications and source records attributed to Anilkumar, A..

2 recordsLinked to original sources

BC-Predict Database: A Curated Resource of Experimentally Validated Markers in Multidrug Resistance in Breast Cancer

BackgroundIn this study, we aim to develop a yearly updatable database that could predict chemotherapeutic drug resistance and overall survival probability in breast cancer patients. Existing drug sensitivity databases depend on correlation-based predictions. In our study, candidates involved in drug resistance are chosen based on cell line validation (overexpression or downregulation or inhibition of candidates) studies, curated manually. Method28,773 mRNA expression signatures from 914 breast cancer patients were extracted from cProsite. 106 of these patients had clinical information and log2 fold change information required for this study. We categorized these patients into deceased and surviving groups from TCGA. To prepare a database that can predict drug resistance and overall survival, we included mRNAs that were over-expressed in at least 80% of the breast cancer patients and mRNAs over-expressed in deceased and surviving groups. In addition, we also reported breast cancer-associated drug resistance candidates which have been reported in cell-line based studies. The database matrix preparation involved an approximate of 15000 manual searches of cell validated studies. (750 candidates x 20 drugs). The database was validated using a publicly available breast cancer patient proteomics data. ResultsOur analysis identified a list of top priority candidates associated with multidrug resistance, categorized based on their resistance to >15 drugs, 5-15 drugs, and 2-4 drugs. Analysis of patient profiles in the database revealed that the number of proteins contributing to drug resistance was high in the poor prognosis category compared to the good prognosis category. ConclusionsOur study highlights the probable gaps in breast cancer drug resistance research, as only a small subset of overexpressed mRNA candidates found in patients are studied in vitro or in vivo experiments focusing on drug resistance. We also identified candidates involved in multidrug resistance, whose role in drug resistance has not been studied in more than 15 drugs. After further validations, this will benefit the clinicians and upcoming CRISPR gene therapeutics.

cancer biology↗

Improved EPR sensitivity for aqueous biological samples using low-volume multi-channel cells and dielectric resonators

Reducing sample volumes for electron paramagnetic resonance (EPR) spectroscopy applications places increasing demands on hardware design to preserve or enhance EPR signal intensity. In this work, the design, fabrication, and testing of dielectric resonators and multi-channel aqueous sample cells for applications in X-band (nominally 9.5 GHz) EPR is presented. Our aim was to maximize the EPR signal intensity for sample sizes of 3-4 L and 200 nL. These advances are summarized as follows: single-crystal sapphire and rutile dielectric resonators with very low loss tangent and high resonator efficiency; minimum dielectric resonator coupling to radiation shield to reduce ohmic losses; 3D printed aqueous sample cells with thin multi-channel construction to minimize radio-frequency dissipation in the sample; and a Gordon coupler for maximum coupling range and minimum stored energy to eliminate frequency shifts during tuning. Sample cell geometries were designed by leveraging insights gained from analytic theory to inform finite-element modeling of electromagnetic fields. Experimental comparisons of multi-channel sample cells using a sapphire resonator exhibited a 2.2-fold increase in EPR signal intensity compared with a standard capillary at 3-4 L, while simulations predict an additional 23% improvement with further 3D printing advances. For samples at 200 nL, a rutile dielectric resonator with a multi-channel sample cell was simulated to improve EPR sensitivity by a 2.7-fold increase compared with a capillary at the same volume.

biophysics↗