Race between virus and inflammasomes: inhibition or escape, intervention and therapy.

The inflammasome is a multiprotein complex that further regulates cell pyroptosis and inflammation by activating caspase-1. The assembly and activation of inflammasome are associated with a variety of diseases. Accumulative studies have shown that inflammasome is a key modulator of the host's defense response to viral infection. Indeed, it has been established that activation of inflammasome occurs during viral infection. At the same time, the host has evolved a variety of corresponding mechanisms to inhibit unnecessary inflammasome activation. Therefore, here, we review and summarize the latest research progress on the interaction between inflammosomes and viruses, highlight the assembly and activation of inflammosome in related cells after viral infection, as well as the corresponding molecular regulatory mechanisms, and elucidate the effects of this activation on virus immune escape and host innate and adaptive immune defenses. Finally, we also discuss the potential therapeutic strategies to prevent and/or ameliorate viral infection-related diseases via targeting inflammasomes and its products.

Pseudogene TDGF1P3 regulates the proliferation and metastasis of colorectal cancer cells via the miR-338-3p-PKM2 axis.

Research in the past decade has revealed significant roles of pseudogenes in colorectal cancer (CRC). Here, the role of teratocarcinoma-derived growth factor 1 pseudogene 3 (TDGF1P3) in regulating the proliferation and invasion of CRC cells was investigated; in addition, its downstream targets were analyzed, and the underlying mechanisms were elucidated. TDGF1P3 was determined to be upregulated in CRC cells and tissues. Silencing TDGF1P3 substantially repressed cell proliferation, migration, and invasion in vitro. Similarly, in vivo assays showed that TDGF1P3 knockdown attenuated tumor growth in nude mice. Mechanistic investigations revealed that TDGF1P3 directly bound to miR-338-3p, thereby preventing miR-338-3p from binding to its target mRNA pyruvate kinase M2 (PKM2). Functional rescue tests indicated that TDGF1P3 regulates CRC cell proliferation and invasion by restraining the miR-338-3p-PKM2 axis. Thus, these data illustrated that TDGF1P3 exerts its oncogenic activity by upregulating PKM2 via competitively binding miR-338-3p, which may be a therapeutic target for CRC.

Functions of regulators of G protein signaling 16 in immunity, inflammation, and other diseases.

Regulators of G protein signaling (RGS) act as guanosine triphosphatase activating proteins to accelerate guanosine triphosphate hydrolysis of the G protein α subunit, leading to the termination of the G protein-coupled receptor (GPCR) downstream signaling pathway. RGS16, which is expressed in a number of cells and tissues, belongs to one of the small B/R4 subfamilies of RGS proteins and consists of a conserved RGS structural domain with short, disordered amino- and carboxy-terminal extensions and an α-helix that classically binds and de-activates heterotrimeric G proteins. However, with the deepening of research, it has been revealed that RGS16 protein not only regulates the classical GPCR pathway, but also affects immune, inflammatory, tumor and metabolic processes through other signaling pathways including the mitogen-activated protein kinase, phosphoinositide 3-kinase/protein kinase B, Ras homolog family member A and stromal cell-derived factor 1/C-X-C motif chemokine receptor 4 pathways. Additionally, the RGS16 protein may be involved in the Hepatitis B Virus -induced inflammatory response. Therefore, given the continuous expansion of knowledge regarding its role and mechanism, the structure, characteristics, regulatory mechanisms and known functions of the small RGS proteinRGS16 are reviewed in this paper to prepare for diagnosis, treatment, and prognostic evaluation of different diseases such as inflammation, tumor, and metabolic disorders and to better study its function in other diseases.

Effects of Clostridium butyricum Capsules Combined with Rosuvastatin on Intestinal Flora, Lipid Metabolism, Liver Function and Inflammation in NAFLD Patients.

The objective of this study was to investigate the effects of Clostridium butyricum capsules combined with rosuvastatin on the intestinal flora, lipid metabolism, liver function and inflammation in patients with nonalcoholic fatty liver disease (NAFLD). For this purpose, a total of 96 patients with NAFLD were selected as research subjects and randomly divided into a control group (n=48) and an observation group (n=48). The Control group was treated with rosuvastatin, based on which observation group received Clostridium butyricum capsule treatment. The efficacy in the two groups of patients was compared, and the intestinal flora, lipid metabolism, liver function and inflammation were observed. Results showed that the efficacy in the observation group was significantly better than that in the control group (p<0.05). After treatment, the content of Eubacterium rectale in the observation group was lower than that in the control group, while the content of Bacteroides thetaiotaomicron and Bifidobacteria was notably higher than that in the control group (p<0.05). Moreover, the observation group had remarkably lower levels of total cholesterol (TC), triglyceride (TG), free fatty acids (FFA), total bilirubin (TBIL), direct bilirubin (DBIL), alanine aminotransferase (ALT), aspartate aminotransferase (AST), procollagen III peptide (PIIIP), collagen-IV (C-IV), hyaluronicacid (HA) and laminin (LN) as well as lower levels of tumor necrosis factor-alpha (TNF-α), catabolite activator protein (CAP) and interleukin-6 (IL-6) in serum than the control group (p<0.05). It was concluded that Clostridium butyricum capsules combined with rosuvastatin can effectively improve intestinal flora imbalance, reduce blood lipid levels, and alleviate liver fibrosis and liver function damage in the treatment of NAFLD, so it is of therapeutic value.

CCL2-mediated monocytes regulate immune checkpoint blockade resistance in pancreatic cancer.

The immunosuppressive microenvironment of pancreatic ductal adenocarcinoma (PDAC) contributes to resistance to immune checkpoint blockade. C-C motif chemokine ligand 2 (CCL2) is believed to participate in pancreatic tumorigenesis, but its role in PDAC progression and resistance to immune checkpoint blockade remains unclear. We hypothesized that CCL2 contributes to the pancreatic immunosuppressive microenvironment. In this study, we found that CCL2 recruits monocytes to and decrease CD8+ T cell infiltration in pancreatic tumors. CCL2 inhibition and monocyte neutralization increased the sensitivity of PDAC to immune checkpoint blockade. The findings of our study suggest the potential of CCL2-mediated monocytes as a target for PDAC treatment.

Inactivation of Pancreatic Stellate Cells by Exendin-4 Inhibits the Migration and Invasion of Pancreatic Cancer Cells.

BACKGROUND: Pancreatic stellate cells (PSCs) are precursor cells of cancer-associated fibroblasts that promote tumor proliferation, invasion, and metastasis. The glucagon-like peptide-1 receptor agonist exendin-4 has been reported to exhibit anticancer effects against several tumor cells; however, the function and mechanism underlying the effects of exendin-4 on pancreatic cancer cells remain unclear. METHODS: Gene expression levels were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assay. Cell viability, migration and invasion were assessed using the cell counting kit-8 (CCK-8), wound healing, and transwell assays, respectively. A xenografted tumor model was established in mouse to evaluate the effects of exendin-4 in vivo. RESULTS: Exendin-4 treatment led to the inactivation of PSCs and suppressed their proliferation and migration. Moreover, we also found that exendin-4 attenuated NF-κB-dependent SDF-1 secretion. Furthermore, pancreatic cancer cells incubated with conditioned medium obtained from exendin-4-treated PSCs showed a decreased ability to proliferate, migrate, and invade as compared to the control cells, which is similar to the effects induced by the CXCR4 inhibitor, AMD3100. Consistent with in vitro results, we also confirmed that exendin-4 indirectly targeted pancreatic cancer cells in vivo by attenuating the function of PSCs and suppressing the deposition of extracellular matrix. CONCLUSION: These results revealed that exendin-4-treated PSCs could suppress pancreatic cancer cell proliferation and invasion, offering a potential strategy for the treatment of pancreatic cancer.

Exosome-mediated transfer of miR-1290 promotes cell proliferation and invasion in gastric cancer via NKD1.

Currently, exosomes rich in RNAs and proteins are regarded as vital mediators of intercellular communication. Here, we aimed to explore the effects of exosomal miR-1290 in gastric cancer (GC) and understand its mechanism of action on GC progression. We first isolated exosomes from serum samples of GC patients and healthy people and characterized them by transmission electron microscopy. Then, we examined the expression level of miR-1290 contained in the exosomes by quantitative reverse-transcription polymerase chain reaction and found that exosomal miR-1290 was overexpressed in GC patients and cell lines. Promotion of proliferation, migration, and invasiveness of GC cells was noted after they were incubated with the isolated miR-1290-rich exosomes compared with incubation with a negative control. Furthermore, we predicted that naked cuticle homolog 1 (NKD1) mRNA is a direct target of miR-1290 and confirmed their interaction by a dual luciferase reporter assay. NKD1 overexpression attenuated the stimulatory effects of miR-1290 on GC cells. Collectively, our results suggest that exosomal miR-1290 enhances GC cell proliferation and invasion by targeting NKD1 mRNA and downregulating NKD1 expression. A better understanding of this process may facilitate the development of novel therapeutic agents for GC.

Raloxifene inhibits bone loss and improves bone strength through an Opg-independent mechanism.

The osteoblast-derived paracrine factor osteoprotegerin (OPG) is considered to play a key role in inhibition of osteoclast formation and activity. Recently, raloxifene, a nonsteroidal benzothiophene, was found to exert anti-resorptive effects via modulating OPG expression in osteoblasts. To explore whether raloxifene regulates bone metabolism via an OPG-dependant pathway in vivo, we investigated the effects of raloxifene on bone loss in Opg-deficient mice. The results show that bone mineral density and bone strength are increased in mice deficient for Opg after treatment with raloxifene for 30 days. Histomorphometric analysis shows that raloxifene can increase bone trabecular area and decrease the number of osteoclasts in Opg (-/-) mice. Moreover, raloxifene reduces Rankl transcription and serum level of Rankl, which is dramatically increased in Opg knockout mice. These results suggest that raloxifene-induced inhibition of bone resorption may be independent of Opg pathway in mice.