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Cell death is a vital event in life. Infections and injuries cause lytic cell death, which gives rise to danger signals that can further induce cell death, inflammation, and tissue damage. The mevalonate (MVA) pathway is an essential, highly conserved and dynamic metabolic pathway. Here, we discover that farnesyl pyrophosphate (FPP), a metabolic intermediate of the MVA pathway, functions as a newly identified danger signal to trigger acute cell death leading to neuron loss in stroke. Harboring both a hydrophobic 15-carbon isoprenyl chain and a heavily charged pyrophosphate head, FPP leads to acute cell death independent of its downstream metabolic pathways. Mechanistically, extracellular calcium influx and the cation channel transient receptor potential melastatin 2 (TRPM2) exhibit essential roles in FPP-induced cell death. FPP activates TRPM2 opening for ion influx. Furthermore, in terms of a mouse model constructing by middle cerebral artery occlusion (MCAO), FPP accumulates in the brain, which indicates the function of the FPP and TRPM2 danger signal axis in ischemic injury. Overall, our data have revealed a novel function of the MVA pathway intermediate metabolite FPP as a danger signal via transient receptor potential cation channels., Competing Interests: The authors have declared that no competing interests exist.

Objective. To explore the role and possible underlying mechanism of miR-486 in ovarian cancer (OC) cells. Methods. The expression of miR-486 and CADM1 was detected by qRT-PCR in OC tissues and adjacent nontumor tissues and OC cell lines. The dual-luciferase reporter gene system was used to determine the targeting relationship between miR-486 and CADM1. CCK-8, colony formation assay, Transwell, and flow cytometry were performed to detect cell proliferation, cell invasion, cell cycle progression, and the apoptotic cell death, respectively. Western blot was carried out to detect the expression of CADM1 protein and the proteins associated with cell cycle progression. Results. miR-486 was significantly upregulated in OC tissues and cells, while CADM1 expression was significantly downregulated. Dual-luciferase reporter assays further confirmed that CADM1 was a target gene of miR-486. Interference with miR-486 could inhibit the proliferation and invasion and promoted the apoptosis of SKOV3 cells. Knocking down both miR-486 and CADM1 significantly increased the SKOV3 cell proliferation, invasion, and the number of cells transitioning from the G0/G1 phase into the S phase of cell cycle and reduced the cellular apoptosis. Western blot analysis revealed that the expression of cell cycle progression-related proteins (CyclinD1, CyclinE, and CDK6) was significantly reduced, and the p21 expression was increased when interfering with both miR-486 and CADM1 expression. Conclusion. Our results suggested that miR-486 could act as a tumor promoter by targeting CADM1 and be a potential therapeutic target for the treatment of OC. [ABSTRACT FROM AUTHOR]

AMBRA1 (activating molecule in Beclin1-regulated autophagy) is a member of the BECN1 (BECLIN1) protein complex, and it plays a role in autophagy, cell death, tumorigenesis and proliferation. We recently reported that on T-cell receptor (TCR) stimulation, AMBRA1 controlled both autophagy and the cell cycle with metabolic regulation. Accumulating evidence has shown that autophagy and metabolic control are pivotal for T-cell activation, clonal expansion and effector/memory cell fate decision. However, it is unknown whether AMBRA1 is involved in T-cell function under physiological conditions. We found that T cells in Ambra1 -conditional knockout (cKO) mice induced an exacerbated graft versus host response when they were transplanted into allogeneic BALB/c mice. Furthermore, Ambra1 -deficient T cells showed increased proliferation and cytotoxic capability toward specific antigens in response to in vivo stimulation using allogeneic spleen cells. This enhanced immune response mainly contributed to naive T-cell hyperactivity. The T-cell hyperactivity observed in this study was similar to those in some metabolic factor-deficient mice, but not those in other pro-autophagic factor-deficient mice. Under the static condition, however, naive T cells were reduced in Ambra1 -cKO mice, the same as in pro-autophagic factor-deficient mice. Collectively, these results suggested that AMBRA1 was involved in regulating T cell-mediated immune responses through autophagy-dependent and -independent mechanisms. [ABSTRACT FROM AUTHOR]

The following information is missing from the Funding statement:W.L. was also supported by grants from National Natural Science Foundation of China (81825010), and Ministry of Science and Technology of China Grants (2021YFC2300500 and 2021YFC2302403).By Jing Chen; Xiaochen Zhang; Liping Li; Xianqiang Ma; Chunxiao Yang; Zhaodi Liu; Chenyang Li; Maria J. Fernandez-Cabezudo; Basel K. al-Ramadi; Chuan Wu; Weishan Huang; Yong Zhang; Yonghui Zhang and Wanli LiuReported by Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Due to the ability of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) to induce cancer cell apoptosis selectively, TRAIL has attracted significant interest in the treatment of cancer. However, although TRAIL triggers apoptosis in a broad range of cancer cells, most primary cancers are often intrinsically TRAIL-resistant, or can acquire resistance after TRAIL treatment, evocating new strategies to overcome TRAIL resistance. Gambogic acid (GA), an active constituent of Garcinia Hanburyi (Teng Huang in Chinese), has been applied for thousands of years for medicinal uses, however, the potential effect of GA in combating cancer resistance remains poorly investigated. In this study, we found that GA could increase the sensitivity of breast cancer cells to TRAIL and enhance TRAIL-induced apoptosis. GA cooperated with TRAIL to decrease the levels of anti-apoptotic proteins and activate Bid (BH3 interacting-domain death agonist) to promote the crosstalk of extrinsic and intrinsic apoptotic signaling, rather than increasing the expression of TRAIL receptors DR4 and DR5. These findings may open a new window in the treatment of breast cancer using TRAIL in combination with GA. [ABSTRACT FROM AUTHOR]

Cervical carcinoma is the fourth most common gynecological cancer. Here we reported the synthesis of oxygen-carried and lipopolysaccharide (LPS)/ indocyanine green (ICG)-loaded nanoparticles (OLI_NPs) for photo-sonodynamic therapy (PSDT) mediated combination therapy to induce systemic antitumor immune responses. We effectively built a new nanoparticle system, a multifunctional nanoagent that integrated the ability of dual-model imaging and therapy for tumors. In this study, we confirmed that OLI_NPs can act as a multifunctional platform that enables not only to diagnose tumors conveniently but also to efficiently provide treatment of in situ tumors, permitting simultaneous dual-mode imaging and localization of the therapy in combination with PSDT-mediated drug release. Furthermore, our combined strategy could effectively depress the tumor development and extend mouse life by the combination of inducing immunogenic cell death (ICD) with encapsulated LPS. In conclusion, combining therapy of OLI_NPs plus PSDT can induce anti-tumor immune responses and tumor antigen-specific immunity in a common TC-1 graft tumor model. Therefore, this combination therapy is a viable technique for cervical cancer treatment. • Photo-sonodynamic mediated with OLI_NPs can treat cervical cancer via inducing ICD [ABSTRACT FROM AUTHOR]