Therapeutic targeting of SLC6A8 creatine transporter suppresses colon cancer progression and modulates human creatine levels.

Colorectal cancer (CRC) is a leading cause of cancer mortality. Creatine metabolism was previously shown to critically regulate colon cancer progression. We report that RGX-202, an oral small-molecule SLC6A8 transporter inhibitor, robustly inhibits creatine import in vitro and in vivo, reduces intracellular phosphocreatine and ATP levels, and induces tumor apoptosis. RGX-202 suppressed CRC growth across KRAS wild-type and KRAS mutant xenograft, syngeneic, and patient-derived xenograft (PDX) tumors. Antitumor efficacy correlated with tumoral expression of creatine kinase B. Combining RGX-202 with 5-fluorouracil or the DHODH inhibitor leflunomide caused regressions of multiple colorectal xenograft and PDX tumors of distinct mutational backgrounds. RGX-202 also perturbed creatine metabolism in patients with metastatic CRC in a phase 1 trial, mirroring pharmacodynamic effects on creatine metabolism observed in mice. This is, to our knowledge, the first demonstration of preclinical and human pharmacodynamic activity for creatine metabolism targeting in oncology, thus revealing a critical therapeutic target.

LXR/ApoE Activation Restricts Innate Immune Suppression in Cancer.

Therapeutic harnessing of adaptive immunity via checkpoint inhibition has transformed the treatment of many cancers. Despite unprecedented long-term responses, most patients do not respond to these therapies. Immunotherapy non-responders often harbor high levels of circulating myeloid-derived suppressor cells (MDSCs)-an immunosuppressive innate cell population. Through genetic and pharmacological approaches, we uncovered a pathway governing MDSC abundance in multiple cancer types. Therapeutic liver-X nuclear receptor (LXR) agonism reduced MDSC abundance in murine models and in patients treated in a first-in-human dose escalation phase 1 trial. MDSC depletion was associated with activation of cytotoxic T lymphocyte (CTL) responses in mice and patients. The LXR transcriptional target ApoE mediated these effects in mice, where LXR/ApoE activation therapy elicited robust anti-tumor responses and also enhanced T cell activation during various immune-based therapies. We implicate the LXR/ApoE axis in the regulation of innate immune suppression and as a target for enhancing the efficacy of cancer immunotherapy in patients.

Informal Caregivers' Experiences of Caring of Multiple Sclerosis Patients: A Qualitative Study.

BACKGROUND: Approximately one-third of people suffering from multiple sclerosis (MS) need long-term care by their families, however, we know little of their experiences. Exploring these experiences can be a guideline to improve the quality of care for MS patients. The goal of this study is to explore informal caregivers' experiences regarding care of MS patients. MATERIALS AND METHODS: A qualitative content analysis method was used to conduct this study in 2014. The study participants were 23 informal caregivers of MS patients who were chosen by purposeful sampling from the MS association of Iran. Data was analyzed by content analysis. RESULTS: The analysis resulted in the emergence of six themes and seventeen subthemes. The main themes were being plagued, mental health damage, being captive among obstacles, perception of the affected family, being an emotional supporter, and need to maintain the functional independence of the patient. CONCLUSIONS: The findings represent the mean of long-term care by informal caregivers of MS patients, as well as the needs and challenges of this relationship. The findings can serve to create a framework for developing nursing care processes and planning educational sessions and support programs for MS patients and their informal caregivers.

Na+/Ca2+-exchanger-mediated Mn2+-enhanced (1)H2O MRI in hypoxic, perfused rat myocardium.

Paramagnetic Mn2+ has emerged in the search for non-invasive magnetic resonance imaging (MRI) techniques to monitor Ca2+ in diagnostic and prognostic cardiovascular disease tests because it both alters MRI contrast and behaves as a Ca2+ 'surrogate' in vivo. However, the reliance on macroscopically averaged measurements to infer microscopic processes constitutes a major limitation of MRI. This investigation circumvents this limitation and contributes an MRI-based myocardial Ca2+-transporter assay, which probes the Na+/Ca2+-exchanger involvement in Mn2+ (and presumably Ca2+) transport by virtue of its response to pharmacological inhibition. In the model employed herein, ex vivo arrested rat hearts underwent normoxia and then hypoxia while a constant (hyperkalemic) perfusion minimized flow (and uncontrolled Ca2+-channel) contributions to Mn2+-enhanced MRI measurements. The results (i) demonstrate that Mn2+ (and presumably Ca2+) accumulates via Na+/Ca2+-exchanger-mediated transport during hyperkalemic hypoxia and further, (ii) implicate hypo-perfusion (rather than the diminished participation of an isolated sarcolemmal Ca2+-transporter) as the mechanism that underlies the reported reductions of Mn2+ accumulation (relative to healthy myocardium) subsequent to myocardial insults in MRI studies. Although myriad studies have employed Mn2+-enhanced MRI in myocardial investigations, this appears to be the first attempt to assay the Na+/Ca2+-exchanger with MRI under highly circumscribed conditions. MRI-based Ca2+)transporter assays, such as the Na+/Ca2+-exchanger assay utilized here, will inevitably impact disciplines in the medical sciences and beyond.

Isolated hepatic tuberculosis in a transplanted liver.

BACKGROUND: The incidence of tuberculosis (TB) has been increasing, especially in immunocompromised patients. It was reported that the overall incidence of TB in solid-organ transplant recipients is 0.8%. Hepatic graft TB was reported once before in a child, who underwent living-related hepatic graft transplantation. CASE REPORT: A 43-year-old man underwent orthotropic liver transplantation (OLT) in October 1999. His pre-transplant work-up was negative for TB (history and PPD skin test). He developed an episode of acute rejection which responded to steroids. He was discharged home on December 1999 with normal liver function tests (LFT). His LFT remained normal during January 2000, but his serum transaminases were found elevated on February 2000 (aspartate aminotransferase [AST] 206, alanine aminotransferase [ALT] 266). A liver biopsy then showed no evidence of TB or cytomegalovirus disease. The patient continued to have stable elevation of his serum AST and ALT until late March 2000 when a repeat liver biopsy showed caseating granuloma. The patient was started on anti-TB medications, with which he was compliant. By mid-May 2000 he was doing well, with significant reduction in his transaminase levels (AST 72, ALT 79). A retrospective inquiry about the donor revealed that he was a healthy young man from India, who died in a road traffic accident. CONCLUSION: To our knowledge our patient appears to be the first case reported of isolated hepatic TB in the OLT patient population. It is likely that the allograft was infected prior to transplantation and the disease was reactivated nearly 3 months after the procedure.