Broadening the infection prevention and control network globally; 2017 Geneva IPC-think tank (part 3).

Background: Healthcare-associated infection (HAI) is a major challenge for patient safety worldwide, and is further complicated by antimicrobial resistance (AMR) due to excessive antimicrobial use in both humans and animals. Existing infection prevention and control (IPC) networks must be strengthened and adapted to better address the global challenges presented by emerging AMR. Methods: In June 2017, 42 international experts convened in Geneva, Switzerland, to discuss two key areas for strengthening the global IPC network: 1) broadening collaboration in IPC; and 2) how to bring the fields IPC and AMR control together. Results: The US Centers for Disease Prevention and Control, the European Centre for Disease Prevention and Control, and the World Health Organization (WHO) convened together with international experts to discuss collaboration and networks, demonstrating the participating organizations' commitment to close collaboration in IPC. The challenge of emerging AMR can only be addressed by strengthening this collaboration across international organisations and between public health and academia. The WHO SAVE LIVES: Clean Your Hands initiative is an example of a successful collaboration between multiple global stakeholders including academia and international public health organisations; it can be used as a model. IPC-strategies are included within the four pillars to combat AMR: surveillance, IPC, antimicrobial and diagnostic stewardship, research and development. The prevention of transmission of multidrug-resistant microorganisms is a patient safety issue, and must be strengthened in the fight against AMR. Conclusions: The working group determined that international organisations should take the lead in creating new networks, which will in turn attract academia and other stakeholders to join. At the same time, they should invest in bringing existing IPC and AMR networks under one umbrella. Transmission of multidrug-resistant microorganisms in hospitals and in the community threatens the success of antimicrobial stewardship programmes, and thus, research and development in IPC should be addressed as an enhanced global priority

Chemical genetics approach to restoring p27Kip1 reveals novel compounds with antiproliferative activity in prostate cancer cells

<p>Abstract</p> <p>Background</p> <p>The cyclin-dependent kinase (CDK) inhibitor p27^Kip1is downregulated in a majority of human cancers due to ectopic proteolysis by the ubiquitin-proteasome pathway. The expression of p27 is subject to multiple mechanisms of control involving several transcription factors, kinase pathways and at least three different ubiquitin ligases (SCF^SKP2, KPC, Pirh2), which regulate p27 transcription, translation, protein stability and subcellular localization. Using a chemical genetics approach, we have asked whether this control network can be modulated by small molecules such that p27 protein expression is restored in cancer cells.</p> <p>Results</p> <p>We developed a cell-based assay for measuring the levels of endogenous nuclear p27 in a high throughput screening format employing LNCaP prostate cancer cells engineered to overexpress SKP2. The assay platform was optimized to Z' factors of 0.48 - 0.6 and piloted by screening a total of 7368 chemical compounds. During the course of this work, we discovered two small molecules of previously unknown biological activity, SMIP001 and SMIP004, which increase the nuclear level of p27 at low micromolar concentrations. SMIPs (small molecule inhibitors of p27 depletion) also upregulate p21^Cip1, inhibit cellular CDK2 activity, induce G1 delay, inhibit colony formation in soft agar and exhibit preferential cytotoxicity in LNCaP cells relative to normal human fibroblasts. Unlike SMIP001, SMIP004 was found to downregulate SKP2 and to stabilize p27, although neither SMIP is a proteasome inhibitor. Whereas the screening endpoint - nuclear p27 - was robustly modulated by the compounds, SMIP-mediated cell cycle arrest and apoptosis were not strictly dependent on p27 and p21 - a finding that is explained by parallel inhibitory effects of SMIPs on positive cell cycle regulators, including cyclins E and A, and CDK4.</p> <p>Conclusions</p> <p>Our data provide proof-of-principle that the screening platform we developed, using endogenous nuclear p27 as an endpoint, presents an effective means of identifying bioactive molecules with cancer selective antiproliferative activity. This approach, when applied to larger and more diverse sets of compounds with refined drug-like properties, bears the potential of revealing both unknown cellular pathways globally impinging on p27 and novel leads for chemotherapeutics targeting a prominent molecular defect of human cancers.</p

Somatic cell type specific gene transfer reveals a tumor-promoting function for p21Waf1/Cip1

How proteins participate in tumorigenesis can be obscured by their multifunctional nature. For example, depending on the cellular context, the cdk inhibitors can affect cell proliferation, cell motility, apoptosis, receptor tyrosine kinase signaling, and transcription. Thus, to determine how a protein contributes to tumorigenesis, we need to evaluate which functions are required in the developing tumor. Here we demonstrate that the RCAS/TvA system, originally developed to introduce oncogenes into somatic cells of mice, can be adapted to allow us to define the contribution that different functional domains make to tumor development. Studying the development of growth-factor-induced oligodendroglioma, we identified a critical role for the Cy elements in p21, and we showed that cyclin D1T286A, which accumulates in the nucleus of p21-deficient cells and binds to cdk4, could bypass the requirement for p21 during tumor development. These genetic results suggest that p21 acts through the cyclin D1–cdk4 complex to support tumor growth, and establish the utility of using a somatic cell modeling system for defining the contribution proteins make to tumor development