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Ghrelin exerts key effects on islet hormone secretion to regulate blood glucose levels. Here, we sought to determine whether ghrelin's effects on islets extend to the alteration of islet size and [beta] cell mass. We demonstrate that reducing ghrelin - by ghrelin gene knockout (GKO), conditional ghrelin cell ablation, or high-fat diet (HFD) feeding - was associated with increased mean islet size (up to 62%), percentage of large islets (up to 854%), and [beta] cell cross-sectional area (up to 51%). In GKO mice, these effects were more apparent in 10- to 12-week-old mice than in 4-week-old mice. Higher [beta] cell numbers from decreased [beta] cell apoptosis drove the increase in [beta] cell cross-sectional area. Conditional ghrelin cell ablation in adult mice increased the [beta] cell number per islet by 40% within 4 weeks. A negative correlation between islet size and plasma ghrelin in HFD-fed plus chow-fed WT mice, together with even larger islet sizes in HFD-fed GKO mice than in HFD-fed WT mice, suggests that reduced ghrelin was not solely responsible for diet-induced obesity-associated islet enlargement. Single-cell transcriptomics revealed changes in gene expression in several GKO islet cell types, including upregulation of Manf, Dnajc3, and Gnas expression in [beta] cells, which supports decreased [beta] cell apoptosis and/or increased [beta] cell proliferation. These effects of ghrelin reduction on islet morphology might prove useful when designing new therapies for diabetes., Introduction Ghrelin is secreted primarily by gastric ghrelin cells (1). It is mainly via binding to CNS and pituitary growth hormone secretagogue receptors (GHSRs) that ghrelin's actions to increase GH [...]

The hormone ghrelin serves a protective role in cancer-related anorexia-cachexia syndrome (CACS)—a condition in which plasma levels of ghrelin rise, its administration lessens CACS severity, and experimentally reduced signaling by its receptor (GHSR) worsens fat loss and anorexia and accelerates death. Yet, actions for the related hormone liver-expressed antimicrobial peptide-2 (LEAP2), which is an endogenous GHSR antagonist, are unexplored in CACS. Here, we found that plasma LEAP2 and LEAP2/ghrelin ratio were lower in Lewis lung carcinoma (LLC) and RM-9 prostate cancer CACS mouse models. Ghrelin deletion exaggerated losses of tumor-free body weight and fat mass, reduced food intake, reduced soleus muscle weight, and/or lowered grip strength in LLC or RM-9 tumor-bearing mice. LEAP2 deletion lessened reductions in tumor-free body weight and fat mass and increased food intake in LLC or RM-9 tumor-bearing mice. In a 55-subject cohort of patients with CACS or weight-stable cancer, the plasma LEAP2/total ghrelin ratio was negatively correlated with 6-month weight change preceding blood collection. These data demonstrate that ghrelin deletion exacerbates CACS in the LLC and RM-9 tumor-bearing mouse models while contrastingly, LEAP2 deletion reduces measures of CACS in these tumor-bearing mouse models. Further, they suggest that lower plasma LEAP2/ghrelin ratio protects against worsened CACS. [ABSTRACT FROM AUTHOR]

Simple Summary: Blood coagulation and cancer are intrinsically related; hyper-thrombotic complications are often observed in certain types of tumors. On the other hand, coagulation proteases are shown to promote the progression of cancer in a variety of unique mechanisms. The present review highlights how coagulation protease-induced signaling contributes to the immune evasion of different cancers, leading to the development and progression of cancer. Understanding the mechanistic insights will aid developing novel therapeutics against coagulation protease-driven response, which could be used in combination with conventional immune checkpoint inhibitors to increase the efficacy of cancer treatment and patient survival. Blood coagulation and cancer are intrinsically connected, hypercoagulation-associated thrombotic complications are commonly observed in certain types of cancer, often leading to decreased survival in cancer patients. Apart from the common role in coagulation, coagulation proteases often trigger intracellular signaling in various cancers via the activation of a G protein-coupled receptor superfamily protease: protease-activated receptors (PARs). Although the role of PARs is well-established in the development and progression of certain types of cancer, their impact on cancer immune response is only just emerging. The present review highlights how coagulation protease-driven PAR signaling plays a key role in modulating innate and adaptive immune responses. This is followed by a detailed discussion on the contribution of coagulation protease-induced signaling in cancer immune evasion, thereby supporting the growth and development of certain tumors. A special section of the review demonstrates the role of coagulation proteases, thrombin, factor VIIa, and factor Xa in cancer immune evasion. Targeting coagulation protease-induced signaling might be a potential therapeutic strategy to boost the immune surveillance mechanism of a host fighting against cancer, thereby augmenting the clinical consequences of targeted immunotherapeutic regimens. [ABSTRACT FROM AUTHOR]

Apart from being the unit of proteins, amino acids have diverse roles. Here we have shown that amino acids guide the differential transportation of a dye molecule to the cellular organelles depending upon the property of their intrinsic functionality. We have conjugated the nitrobenzofurazan (NBD) moiety with two amino acids (lysine and histidine derivatives) with a linker. Both derivates are water‐soluble and biocompatible in nature. Surprisingly, we found that lysine‐conjugated NBD (NBD‐Lys) stains lipid droplets whereas histidine‐conjugated NBD (NBD‐His) stains lysosomes. We also measured the spectral properties of these two NBD conjugates. The results depict that both conjugates are extremely stable both in air and under inert atmosphere, and the fluorescence of the derivatives remains almost unaltered at different pH. Further by altering the functionality of the side chain, we established the contribution of each functional group towards this differential organelle targeting. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide, with an estimated 750,000 deaths in 2022. Recent emergence of molecular targeted agents (MTAs) and immune checkpoint inhibitors (ICIs) and their combination therapies have been transforming HCC care, but their prognostic impact in advanced-stage disease remains unsatisfactory. In addition, their application to early-stage disease is still an unmet need. Omics profiling studies have elucidated recurrent and heterogeneously present molecular aberrations involved in pro-cancer tumor (immune) microenvironment that may guide therapeutic strategies. Recurrent aberrations such somatic mutations in TERT promoter and TP53 have been regarded undruggable, but recent studies have suggested that these may serve as new classes of therapeutic targets. HCC markers such as alpha-fetoprotein (AFP), glypican-3 (GPC3), and epithelial cell adhesion molecule (EpCAM) have also been explored as therapeutic targets. These molecular features may be utilized as biomarkers to guide the application of new approaches as companion biomarkers to maximize therapeutic benefits in patients who are likely to benefit from the therapies, while minimizing unnecessary harm in patients who will not respond. The explosive number of new agents in the pipelines have posed challenges in their clinical testing. Novel clinical trial designs guided by predictive biomarkers have been proposed to enable their efficient and cost-effective evaluation. These new developments collectively facilitate clinical translation of personalized molecular-targeted therapies in HCC and substantially improve prognosis of HCC patients.

The association between idiopathic venous thrombosis and occult cancer is widely recognized. However, the comprehensive understanding of how thrombin, generated during the process of thrombosis, possesses the potential to augment the malignant phenotype is still not well understood. The coagulation protease thrombin mediates its effects by cleaving protease-activated receptor 1 (PAR1), a receptor abundantly expressed on the surface of triple-negative breast cancer (TNBC) cells. While emerging evidence implicates coagulation proteases in facilitating cancer progression, the precise molecular pathways underlying thrombin-mediated induction of chemoresistance remain poorly defined. Here, we demonstrate that thrombin-induced PAR1 activation in TNBC cells promotes the development of a multidrug-resistant phenotype, mechanistically linked to the upregulation of the pro-survival protein MCL1. Genetic ablation of MCL1 sensitizes TNBC cells to cytotoxic drugs despite thrombin exposure, affirming MCL1's functional importance. Chromatin immunoprecipitation analyses reveal thrombin triggers protein kinase A-dependent phosphorylation of serine 133 residues of cAMP-responsive element-binding protein (CREB), enhancing CREB's affinity for the co-activators CBP and p300. Furthermore, thrombin treatment induces the nuclear translocation of CREB-regulated transcription coactivator 2 (CRTC2) in a calcium-dependent manner, which collectively interacts with CREB/CBP-P300. The coordinated action of these transcriptional co-activators facilitates the transcriptional induction of MCL1. We further report that PAR1 activation augments MCL1 binding to the deubiquitinase USP9X, reducing MCL1 turnover. Our pre-clinical breast cancer murine model also shows that genetic deletion of PAR1 sensitizes breast cancer cells to chemotherapeutic drugs in vivo. Collectively, these findings emphasize the thrombin-PAR1 axis as a novel driver of chemoresistance. Utilizing FDA-approved oral anticoagulants for selective blocking of thrombin action may serve as a potential therapeutic adjunct for the treatment of triple-negative breast cancer., Competing Interests: Conflict of interest The author declares that they have no conflicts of interest with the content of the article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background & Aims: Hepatocellular carcinoma (HCC) risk stratification is an urgent unmet need for cost-effective HCC screening and early detection in patients with cirrhosis to improve poor HCC prognosis., Methods: Molecular (prognostic liver secretome signature with α-fetoprotein) and clinical (aMAP [age, male sex, albumin-bilirubin, and platelets] score) variable-based scores were integrated into PAaM (prognostic liver secretome signature with α-fetoprotein plus age, male sex, albumin-bilirubin, and platelets), which was subsequently validated in 2 phase 3 biomarker validation studies: the statewide Texas HCC Consortium and nationwide HCC Early Detection Strategy prospective cohorts, following the prospective specimen collection, retrospective blinded evaluation design. The associations between baseline PAaM and incident HCC were assessed using Fine-Gray regression, with overall death and liver transplantation as competing events., Results: Of 2156 patients with cirrhosis in the Texas HCC Consortium, PAaM identified 404 (19%) high-risk, 903 (42%) intermediate-risk, and 849 (39%) low-risk patients with annual HCC incidence rates of 5.3%, 2.7%, and 0.6%, respectively. Compared with low-risk patients, high- and intermediate-risk groups had sub-distribution hazard ratios for incident HCC of 7.51 (95% CI, 4.42-12.8) and 4.20 (95% CI, 2.52-7.01), respectively. Of 1328 patients with cirrhosis in the HCC early detection strategy, PAaM identified 201 high-risk (15%), 540 intermediate-risk (41%), and 587 low-risk (44%) patients, with annual HCC incidence rates of 6.2%, 1.8%, and 0.8%, respectively. High- and intermediate-risk groups were associated with sub-distribution hazard ratios for incident HCC of 6.54 (95% CI, 3.85-11.1) and 1.77 (95% CI, 1.02-3.08), respectively. Subgroup analysis showed robust risk stratification across HCC etiologies, including metabolic dysfunction-associated steatotic liver disease and cured hepatitis C infection., Conclusions: PAaM enables accurate HCC risk stratification in patients with cirrhosis from contemporary etiologies., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Apart from being the unit of proteins, amino acids have diverse roles. Here we have shown that amino acids guide the differential transportation of a dye molecule to the cellular organelles depending upon the property of their intrinsic functionality. We have conjugated the nitrobenzofurazan (NBD) moiety with two amino acids (lysine and histidine derivatives) with a linker. Both derivates are water-soluble and biocompatible in nature. Surprisingly, we found that lysine-conjugated NBD (NBD-Lys) stains lipid droplets whereas histidine-conjugated NBD (NBD-His) stains lysosomes. We also measured the spectral properties of these two NBD conjugates. The results depict that both conjugates are extremely stable both in air and under inert atmosphere, and the fluorescence of the derivatives remains almost unaltered at different pH. Further by altering the functionality of the side chain, we established the contribution of each functional group towards this differential organelle targeting., (© 2022 Wiley-VCH GmbH.)