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The Hippo pathway plays critical roles in cell growth, differentiation, organ development and tissue homeostasis, whereas its dysregulation can lead to tumorigenesis. YAP and TAZ are transcription co-activators and represent the main downstream effectors of the Hippo pathway. Here, we show that heat stress induces a strong and rapid YAP dephosphorylation and activation. The effect of heat shock on YAP is dominant to other signals known to modulate the Hippo pathway. Heat shock inhibits LATS kinase by promoting HSP90-dependent LATS interaction with and inactivation by protein phosphatase 5. Heat shock also induces LATS ubiquitination and degradation. YAP and TAZ are crucial for cellular heat shock responses, including the heat shock transcriptome and cell viability. This study uncovers previously unknown mechanisms of Hippo regulation by heat shock, as well as physiological functions of YAP, in the heat stress response. Our observations also reveal a potential combinational therapy involving hyperthermia and targeting of the Hippo pathway.

Kalimeris indica (L.) Sch Bip (K. indica) is a plant of the genus Kalimeris in Asteraceae, and its whole herb can be used as medicine for the treatment of intestinal inflammatory diseases. But the mechanism is not clear. Therefore, this study was designed to explore the mechanism of K. indica (KI) in colitis-associated colorectal cancer. The expression levels of miR-31-5p and proinflammatory factors were detected using THP-1 and Caco2 cells in vitro. KI could rescue the upregulation of miR-31-5p induced by IL-6 and TNF-α in Caco2 and THP-1 cells. In LPS-stimulated PMA-differentiated THP-1 cells, KI restored miR-31-5p expression by downregulating the expression of IL-6 and TNF-α. C57BL/6 mice were used to construct CAC model through the induction of azoxymethane/dextran sulfate sodium. The successfully established CAC mice were treated with water extract of KI through intragastric administration for 5 weeks. The result showed that KI could significantly reduce the atypical hyperplasia in colon tissue, and inhibit the expression of proinflammatory factors such as IL-6, TNF, IL-11, IL-7, etc. At the same time, KI could restore the level of miR-31-5p in mice, and therefore the downstream LATS2 to inhibit the development of CAC. These above results indicate that KI is a potentially effective herb medicine to prevent CAC.

Adoptive transfer of antigen-specific T cells represents a major advance in cancer immunotherapy, with robust clinical outcomes in some patients.sup.1. Both the number of transferred T cells and their differentiation state are critical determinants of effective responses.sup.2,3. T cells can be expanded with T cell receptor (TCR)-mediated stimulation and interleukin-2, but this can lead to differentiation into effector T cells.sup.4,5 and lower therapeutic efficacy.sup.6, whereas maintenance of a more stem-cell-like state before adoptive transfer is beneficial.sup.7. Here we show that H9T, an engineered interleukin-2 partial agonist, promotes the expansion of CD8.sup.+ T cells without driving terminal differentiation. H9T led to altered STAT5 signalling and mediated distinctive downstream transcriptional, epigenetic and metabolic programs. In addition, H9T treatment sustained the expression of T cell transcription factor 1 (TCF-1) and promoted mitochondrial fitness, thereby facilitating the maintenance of a stem-cell-like state. Moreover, TCR-transgenic and chimeric antigen receptor-modified CD8.sup.+ T cells that were expanded with H9T showed robust anti-tumour activity in vivo in mouse models of melanoma and acute lymphoblastic leukaemia. Thus, engineering cytokine variants with distinctive properties is a promising strategy for creating new molecules with translational potential. H9T, an engineered IL-2 partial agonist, promotes the expansion of T cells while maintaining a stem-cell-like state, leading to improved efficacy of adoptive cell therapy in mouse models of melanoma and acute lymphoblastic leukaemia., Author(s): Fei Mo [sup.1] , Zhiya Yu [sup.2] , Peng Li [sup.1] , Jangsuk Oh [sup.1] , Rosanne Spolski [sup.1] , Liang Zhao [sup.3] , Caleb R. Glassman [sup.4] , [...]

Lung cancer is the leading global cause of cancer‐related death, however, resistance to chemotherapy drugs remains a huge barrier to effective treatment. The elevated recruitment of myeloid derived suppressor cells (MDSCs) to tumour after chemotherapy has been linked to resistance of chemotherapy drugs. Nevertheless, the specific mechanism remains unclear. oxPAPC is a bioactive principal component of minimally modified low‐density lipoproteins and regulates inflammatory response. In this work, we found that cisplatin, oxaliplatin and ADM all increased oxPAPC release in tumour. Treating macrophages with oxPAPC in vitro stimulated the secretion of MCP‐1 and LTB4, which strongly induced monocytes and neutrophils chemotaxis, respectively. Injection of oxPAPC in vivo significantly upregulated the percentage of MDSCs in tumour microenvironment (TME) of wild‐type LL2 tumour‐bearing mice, but not CCL2−/− mice and LTB4R−/− mice. Critically, oxPAPC acted as a pro‐tumor factor in LL2 tumour model. Indeed, cisplatin increased oxPAPC level in tumour tissues of WT mice, CCL2−/− and LTB4R−/− mice, but caused increased infiltration of Ly6Chigh monocytes and neutrophils only in WT LL2‐bearing mice. Collectively, our work demonstrates cisplatin treatment induces an overproduction of oxPAPC and thus recruits MDSCs infiltration to promote the tumour growth through the MCP‐1/CCL2 and LTB4/LTB4R pathways, which may restrict the effect of multiple chemotherapy. This provides evidence for a potential strategy to enhance the efficacy of multiple chemotherapeutic drugs in the treatment of lung cancer by targeting oxPAPC. [ABSTRACT FROM AUTHOR]

In the complement system, C3 is a central component in complement activation, immune defense and immune regulation. In all pathways of complement activation, the pivotal step is conversion of the component C3 to C3b and C3a, which is responsible to eliminate the pathogen and opsonization. In this study, we examined the immunological properties of C3 and its activated fragment C3a from Japanese flounder (Paralichthys olivaceus) (PoC3 and PoC3a), a teleost species with important economic value. PoC3 is composed of 1655 amino acid residues, contains the six domains and highly conserved GCGEQ sequence of the C3 family. We found that PoC3 expression occurred in nine different tissues and was upregulated by bacterial challenge. In serum, PoC3 was able to bind to a broad-spectrum of bacteria, and purified native PoC3 could directly kill specific pathogen. When PoC3 expression in Japanese flounder was knocked down by siRNA, serum complement activity was significantly decreased, and bacterial replication in fish tissues was significantly increased. Recombinant PoC3a (rPoC3a) exhibited apparent binding capacities to bacteria and Japanese flounder peripheral blood leukocytes (PBL) and induce chemotaxis of PBL. Japanese flounder administered rPoC3a exhibited enhanced resistance against bacterial infection. Taken together, these results indicate that PoC3 is likely a key factor of complement activation, and PoC3 and PoC3a are required for optimal defense against bacterial infection in teleost.

Translocation and assembly module (TAM) is a protein channel known to mediate the secretion of virulence factors during pathogen infection. Edwardsiella tarda is a Gram-negative bacterium that is pathogenic to a wide range of farmed fish and other hosts including humans. In this study, we examined the function of the two components of the TAM, TamA and TamB, of E. tarda (named tamAEt and tamBEt, respectively). TamAEt was found to localize on the surface of E. tarda and be recognizable by TamAEt antibody. Compared to the wild type, the tamA and tamB knockouts, TX01ΔtamA and TX01ΔtamB, respectively, were significantly reduced in motility, flagella formation, invasion into host cells, intracellular replication, dissemination in host tissues, and inducing host mortality. The lost virulence capacities of TX01ΔtamA and TX01ΔtamB were restored by complementation with the tamAEt and tamBEt genes, respectively. Furthermore, TX01ΔtamA and TX01ΔtamB were significantly impaired in the ability to survive under low pH and oxidizing conditions, and were unable to maintain their internal pH balance and cellular structures in acidic environments, which led to increased susceptibility to lysozyme destruction. Taken together, these results indicate that TamAEt and TamBEt are essential for the virulence of E. tarda and required for E. tarda to survive under stress conditions.