Prevalence and Mechanisms of Skeletal Muscle Atrophy in Metabolic Conditions.

Skeletal muscle atrophy is prevalent in a myriad of pathological conditions, such as diabetes, denervation, long-term immobility, malnutrition, sarcopenia, obesity, Alzheimer's disease, and cachexia. This is a critically important topic that has significance in the health of the current society, particularly older adults. The most damaging effect of muscle atrophy is the decreased quality of life from functional disability, increased risk of fractures, decreased basal metabolic rate, and reduced bone mineral density. Most skeletal muscle in humans contains slow oxidative, fast oxidative, and fast glycolytic muscle fiber types. Depending on the pathological condition, either oxidative or glycolytic muscle type may be affected to a greater extent. This review article discusses the prevalence of skeletal muscle atrophy and several mechanisms, with an emphasis on high-fat, high-sugar diet patterns, obesity, and diabetes, but including other conditions such as sarcopenia, Alzheimer's disease, cancer cachexia, and heart failure.

Endometrial cancer rate in Hormone replacement therapy users with postmenopausal bleeding: Retrospective cohort study.

OBJECTIVE: To establish the endometrial cancer detection rate in women using hormone replacement therapy presenting with postmenopausal bleeding. STUDY DESIGN: Retrospective cohort study. Setting and populationRapid access gynaecology clinic at a tertiary hospital. Women aged under 60 years referred with postmenopausal bleeding. METHODS: Retrospective study of referrals received between 1 January 2019 and 31 December 2020 including Hormone replacement therapy (HRT) use and histological diagnosis. MAIN OUTCOME MEASURES: Histological diagnosis of endometrial cancer, borderline ovarian tumour or endometrial intraepithelial neoplasia. STATISTICAL ANALYSIS: Chi squared test. RESULTS: 1363 women were included. 214 women were using HRT when they experienced PMB and only one of these had endometrial cancer at histology (cancer detection rate 0.47%). 25 of the 1124 women who were not using HRT were diagnosed with endometrial cancer on histology (cancer detection rate 2.18%). Chi squared statistical analysis confirmed this was statistically significant (p value .0156). CONCLUSIONS: The endometrial cancer detection rate in women aged under 60 years using HRT with PMB is very low. Referral on a two-week wait pathway for suspected cancer diagnosis induces stress and anxiety for the woman and may lead to more invasive initial investigation even though other diagnoses are far more likely. Women aged under 60 years with postmenopausal bleeding that have either commenced HRT or had a change to their preparation within the last 6 months should be seen on a less urgent referral pathway if necessary given the very low probability of endometrial cancer.

iPSC-derived NK cells maintain high cytotoxicity and enhance in vivo tumor control in concert with T cells and anti-PD-1 therapy.

The development of immunotherapeutic monoclonal antibodies targeting checkpoint inhibitory receptors, such as programmed cell death 1 (PD-1), or their ligands, such as PD-L1, has transformed the oncology landscape. However, durable tumor regression is limited to a minority of patients. Therefore, combining immunotherapies with those targeting checkpoint inhibitory receptors is a promising strategy to bolster antitumor responses and improve response rates. Natural killer (NK) cells have the potential to augment checkpoint inhibition therapies, such as PD-L1/PD-1 blockade, because NK cells mediate both direct tumor lysis and T cell activation and recruitment. However, sourcing donor-derived NK cells for adoptive cell therapy has been limited by both cell number and quality. Thus, we developed a robust and efficient manufacturing system for the differentiation and expansion of high-quality NK cells derived from induced pluripotent stem cells (iPSCs). iPSC-derived NK (iNK) cells produced inflammatory cytokines and exerted strong cytotoxicity against an array of hematologic and solid tumors. Furthermore, we showed that iNK cells recruit T cells and cooperate with T cells and anti-PD-1 antibody, further enhancing inflammatory cytokine production and tumor lysis. Because the iNK cell derivation process uses a renewable starting material and enables the manufacturing of large numbers of doses from a single manufacture, iNK cells represent an "off-the-shelf" source of cells for immunotherapy with the capacity to target tumors and engage the adaptive arm of the immune system to make a "cold" tumor "hot" by promoting the influx of activated T cells to augment checkpoint inhibitor therapies.

Novel Miniaturized Drug Conjugate Leverages HSP90-driven Tumor Accumulation to Overcome PI3K Inhibitor Delivery Challenges to Solid Tumors.

The PI3K pathway is considered a master regulator for cancer due to its frequent activation, making it an attractive target for pharmacologic intervention. While substantial efforts have been made to develop drugs targeting PI3K signaling, few drugs have been able to achieve the inhibition necessary for effective tumor control at tolerated doses. HSP90 is a chaperone protein that is overexpressed and activated in many tumors and as a consequence, small-molecule ligands of HSP90 are preferentially retained in tumors up to 20 times longer than in normal tissue. We hypothesize that the generation of conjugates that use a HSP90-targeting ligand and a payload such as copanlisib, may open the narrow therapeutic window of this and other PI3K inhibitors. In support of this hypothesis, we have generated a HSP90-PI3K drug conjugate, T-2143 and utilizing xenograft models, demonstrate rapid and sustained tumor accumulation of the conjugate, deep pathway inhibition, and superior efficacy than the PI3K inhibitor on its own. Selective delivery of T-2143 and the masking of the inhibitor active site was also able to mitigate a potentially dose-limiting side effect of copanlisib, hyperglycemia. These data demonstrate that by leveraging the preferential accumulation of HSP90-targeting ligands in tumors, we can selectively deliver a PI3K inhibitor leading to efficacy in multiple tumor models without hyperglycemia in mice. These data highlight a novel drug delivery strategy that allows for the potential opening of a narrow therapeutic window through specific tumor delivery of anticancer payloads and reduction of toxicity.

Optimized surface markers for the prospective isolation of high-quality hiPSCs using flow cytometry selection.

hiPSC derivation and selection remains inefficient; with selection of high quality clones dependent on extensive characterization which is not amenable to high-throughput (HTP) approaches. We recently described the use of a cocktail of small molecules to enhance hiPSC survival and stability in single cell culture and the use of flow cytometry cell sorting in the HTP-derivation of hiPSCs. Here we report an enhanced protocol for the isolation of bona fide hiPSCs in FACS-based selection using an optimized combination of cell surface markers including CD30. Depletion of CD30(+) cells from reprogramming cultures almost completely abolished the NANOG and OCT4 positive sub-population, suggesting it is a pivotal marker of pluripotent cells. Combining CD30 to SSEA4 and TRA-1-81 in FACS greatly enhanced specificity and efficiency of hiPSC selection and derivation. The current method allows for the efficient and automated, prospective isolation of high-quality hiPSC from the reprogramming cell milieu.

Nutrition evidence-based guidelines for treating hyperlipidemia in children with type 1 diabetes: a case presentation.

PURPOSE: The purpose of this case presentation is to review the current nutrition evidence-based guidelines and treatment goals for hyperlipidemia in children with type 1 diabetes. The American Heart Association (AHA) places children with type 1 diabetes in the highest tier for cardiovascular risk. METHODS: Early screening for hyperlipidemia in children with diabetes is recommended to identify those children at risk. If the fasting low-density lipoprotein cholesterol (LDL-C) level is > or = 100 mg/dL (2.6 mmol/L), medical nutrition therapy is recommended as the first line of treatment to reach the desired goal (LDL-C <100 mg/dL). Medical nutrition therapy includes the following: decreasing saturated fat (<7% total calories), avoiding trans fatty acids, decreasing total cholesterol to <200 mg daily, increasing soluble fiber, and adding phytosterols daily. RESULTS: The patient discussed in this case presentation achieved a desired LDL-C level <100 mg/dL (2.6 mmol/L) by following the recommended heart-healthy guidelines. Statin therapy was not considered unless the LDL-C goal, <130 mg/dL (3.38 mmol/L), was not achieved by diet alone. CONCLUSIONS: In this case study, evidence-based nutrition guidelines have been evaluated and reviewed to demonstrate heart-healthy eating for children with hyperlipidemia and type 1 diabetes. It is known that approximately 40% to 50% of children with elevated lipids will continue to have abnormal lipids into adolescence and early adulthood. Therefore, early screening is recommended by the AHA to track lipid changes during childhood and adolescence and to begin treating abnormal LDL-C levels to prevent the development of atherosclerosis.

Cloning and expression of human mitogen-activated protein kinase kinase 7gamma1.

Mitogen-activated protein kinase kinase 7 (MKK7) is a direct activator of the mitogen-activated protein kinase family member c-Jun N-terminal kinase (JNK). MKK7 activates JNK via phosphorylation of a threonine and tyrosine residue in a Thr-Pro-Tyr motif within kinase subdomain VIII. To date at least six different isoforms of murine MKK7 have been identified. However, only three isoforms of human MKK7 have been reported. We report here the cloning of hMKK7gamma1, the human homolog of murine MKK7gamma1. Expression of hMKK7gamma1 mRNA was assessed and transcripts were present in low levels in placenta, fetal liver, and skeletal muscle. PCR results indicate that hMKK7gamma1 is expressed in various normal tissues, tumors, and in synoviocytes from rheumatoid and osteoarthritis patients. Recombinant hMKK7gamma1 can be phosphorylated and activated by MEKK1. Further studies will provide insight into the role for hMKK7gamma1 versus other MKK7 isoforms.

Global genechip profiling to identify genes responsive to p53-induced growth arrest and apoptosis in human lung carcinoma cells.

To identify critical genes that mediate p53-induced growth arrest and apoptosis at a global level, we profiled a human lung carcinoma cell model in which cells undergo growth arrest and apoptosis in a p53 and DNA damage-dependent manner. Profiling of the Affymetrix human HG-U1333 GeneChip, covering the entire human transcriptome, revealed about 3, 000 unique genes either induced or repressed during p53-induced growth arrest or apoptosis, respectively. A total of 1, 057 genes, including many well-known p53 targets, responded to both conditions. A mini apoptotic protein database was generated from 3, 033 unique apoptosis responsive genes. Analysis of this database yielded 23 proteins with a pro-apoptotic BH3 domain and three with anti-apoptotic BIR2/BIR3 domains, including well-known p53 targets: Bax, Puma, Noxa and survivin. In addition, 14 mitochondrial proteins were identified that contain a pro-apoptotic AVPI-like motif, and 15 proteins were identified that contain a DAVPI-like domain with the potential of being cleaved by caspases during apoptosis to release the AVPI motif. Many of the genes we identified with these domains do contain p53-binding sites either in the promoter or in the first three introns, suggesting a high probability of being direct p53 targets. Pathway analysis revealed that p53 might control the Wnt pathway through transcriptional regulation of some of its components. Thus, global chip profiling coupled with bioinformatics analysis is a powerful tool in identification of genes critical for p53-induced apoptosis. Further characterization of these genes will lead to a better understanding of the mechanism of p53 action and p53 regulation of other signaling pathways. It will also provide novel cancer drug targets for further validation.

AMPK-beta1 subunit is a p53-independent stress responsive protein that inhibits tumor cell growth upon forced expression.

In an effort to search for genes responsible for cell growth arrest and/or apoptosis associated with p53 signaling pathways, we profiled a human lung carcinoma line H1299, expressing a temperature-sensitive p53 (V138) against Affymetric human U95Av2 GeneChip A, consisting of 12 000 genes. 133 genes were identified that were either induced or repressed in response to p53-dependent cell growth arrest and apoptotic conditions. Among them, the beta1 subunit, but not other subunits of the AMP-activated protein kinase (AMPK) was strongly induced. The p53 consensus binding site search in the AMPK-beta1 promoter and the first intron identified four such putative sites. However, p53 failed to bind to any of these sites as assayed by in vitro gel retardation and in vivo chromatin immunoprecipitation. Furthermore, northern analysis showed that induction of this gene is independent of p53, as increased expression of the gene was observed in p53 null H1299/Neo control cells when the temperature was shifted to 32 degrees C. Moreover, a DNA damaging agent, etoposide, also induced beta1 subunit expression in multiple human tumor cells, regardless of p53 status. Thus, the beta1 subunit of AMPK is not a p53 downstream target gene, but can be induced by cold shock or the chemotherapeutic drug, etoposide in a p53-independent manner. To determine the biological significance of AMPK-beta1 induction, we over-expressed the gene in two tumor cell lines, H1299 and U2-OS. In both lines, forced AMPK-beta1 expression inhibits tumor cell growth, suggesting that AMPK-beta1 induction may facilitate stress-induced growth inhibition and cell killing.