Background The generation of over 69 spliced HIV-1 mRNAs from one primary transcript by alternative RNA splicing emphasizes the central role that RNA processing plays in HIV-1 replication. Control is mediated in part through the action of host SR proteins whose activity is regulated by multiple SR kinases (CLK1-4, SRPKs). Methods Both shRNA depletion and small molecule inhibitors of host SR kinases were used in T cell lines and primary cells to evaluate the role of these factors in the regulation of HIV-1 gene expression. Effects on virus expression were assessed using western blotting, RT-qPCR, and immunofluorescence. Results The studies demonstrate that SR kinases play distinct roles; depletion of CLK1 enhanced HIV-1 gene expression, reduction of CLK2 or SRPK1 suppressed it, whereas CLK3 depletion had a modest impact. The opposing effects of CLK1 vs. CLK2 depletion were due to action at distinct steps; reduction of CLK1 increased HIV-1 promoter activity while depletion of CLK2 affected steps after transcript initiation. Reduced CLK1 expression also enhanced the response to several latency reversing agents, in part, by increasing the frequency of responding cells, consistent with a role in regulating provirus latency. To determine whether small molecule modulation of SR kinase function could be used to control HIV-1 replication, we screened a GSK library of protein kinase inhibitors (PKIS) and identified several pyrazolo[1,5-b] pyridazine derivatives that suppress HIV-1 gene expression/replication with an EC50 ~ 50 nM. The compounds suppressed HIV-1 protein and viral RNA accumulation with minimal impact on cell viability, inhibiting CLK1 and CLK2 but not CLK3 function, thereby selectively altering the abundance of individual CLK and SR proteins in cells. Conclusions These findings demonstrate the unique roles played by individual SR kinases in regulating HIV-1 gene expression, validating the targeting of these functions to either enhance latency reversal, essential for “Kick-and-Kill” strategies, or to silence HIV protein expression for “Block-and-Lock” strategies.

Purpose: Small cell lung cancer (SCLC) is an aggressive disease with an overall 5-year survival rate of less than 10%. Treatment for SCLC with cisplatin/etoposide chemotherapy (C/E) ± radiotherapy has changed modestly over several decades. The ubiquitin-proteasome system is an underexplored therapeutic target for SCLC. We preclinically evaluated TAK-243, a first-in-class small molecule E1 inhibitor against UBA1. Experimental Design: We assessed TAK-243 in 26 SCLC cell-lines as monotherapy and combined with C/E, the PARP-inhibitor, olaparib, and with radiation using cell viability assays. We interrogated TAK-243 response with gene expression to identify candidate biomarkers. We evaluated TAK-243 alone and in combination with olaparib or radiotherapy with SCLC patient-derived xenografts (PDX). Results: Most SCLC cell lines were sensitive to TAK-243 monotherapy (EC50 median 15.8 nmol/L; range 10.2 nmol/L–367.3 nmol/L). TAK-243 sensitivity was associated with gene-sets involving the cell cycle, DNA and chromatin organization, and DNA damage repair, while resistance associated with cellular respiration, translation, and neurodevelopment. These associations were also observed in SCLC PDXs. TAK-243 synergized with C/E and olaparib in vitro across sensitive and resistant SCLC cell lines. Considerable TAK-243–olaparib synergy was observed in an SCLC PDX resistant to both drugs individually. TAK-243 radiosensitization was also observed in an SCLC PDX. Conclusions: TAK-243 displays efficacy in SCLC preclinical models. Enrichment of gene sets is associated with TAK-243 sensitivity and resistance. TAK-243 exhibits synergy when combined with genotoxic therapies in cell lines and PDXs. TAK-243 is a potential therapeutic strategy to improve SCLC patient outcomes, both as a single agent and in combination with existing therapies.

This paper presents the design and analysis of a relatively new wireless power transfer technique using capacitive coupling, named Capacitive power transfer (CPT). In general, CPT system has been introduced as an attractive alternative to the former inductive coupling method. This is because CPT uses lesser number of components, simpler topology, enhanced EMI performance and better strength to surrounding metallic elements. In this work, aluminium sheet is used as a capacitive coupling at transmitter and receiver side. Moreover, a Class-E resonant inverter together with π1a impedance matching network has been proposed because of its ability to perform the dc-to-ac inversion well. It helps the CPT system to achieve maximum power transfer. The CPT system is designed and simulated by using MATLAB/Simulink software. The validity of the proposed concept is then verified by conducting a laboratory experimental of CPT system. The proposed system able to generate a 9.5W output power through a combined interface capacitance of 2.44nF, at an operating frequency of 1MHz, with 95.10% efficiency. The proposed CPT system with impedance matching network also allows load variation in the range of 20% from its nominal value while maintaining the efficiency over 90%. Keyword:Aluminum sheet Capacitive power transfer MATLAB simulink Wireless power transfer impedance matching