MANF brakes TLR4 signaling by competitively binding S100A8 with S100A9 to regulate macrophage phenotypes in hepatic fibrosis

Mesencephalic astrocyte-derived neurotrophic factor inhibits cervical cancer progression via regulating macrophage phenotype

BACKGROUND

Cervical cancer is a common gynecologic malignant tumor, but the critical factors affecting cervical cancer progression are still not well demonstrated. Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been widely recognized as an anti-inflammatory factor to regulate macrophage polarization. In this study, the effect and mechanism of MANF on cervical cancer were preliminarily explored.

METHODS AND RESULTS

Kaplan-Meier curve was used to show the overall survival time of the involved cervical cancer patients with high and low MANF expression in cervical cancer tissues. MANF was highly expressed in peritumoral tissues of cervical carcinoma by using immunohistochemistry and western blot. MANF mRNA level was detected by using qRT-PCR. Dual-labeled immunofluorescence showed MANF was mainly expressed in macrophages of cervical peritumoral tissues. Moreover, MANF-silenced macrophages promoted HeLa and SiHa cells survival, migration, invasion and EMT via NF-κB signaling activation. The results of tumor formation in nude mice indicated MANF-silenced macrophages promoted cervical tumor formation in vivo.

CONCLUSION

Our study reveals an inhibitory role of MANF in cervical cancer progression, indicating MANF as a new and valuable therapeutic target for cervical cancer treatment.

Alarmin S100A8 imparts chemoresistance of esophageal cancer by reprogramming cancer-associated fibroblasts

Chemotherapy remains the first-line treatment for advanced esophageal cancer. However, durable benefits are achieved by only a limited subset of individuals due to the elusive chemoresistance. Here, we utilize patient-derived xenografts (PDXs) from esophageal squamous-cell carcinoma to investigate chemoresistance mechanisms in preclinical settings. We observe that activated cancer-associated fibroblasts (CAFs) are enriched in the tumor microenvironment of PDXs resistant to chemotherapy. Mechanistically, we reveal that cancer-cell-derived S100A8 triggers the intracellular RhoA-ROCK-MLC2-MRTF-A pathway by binding to the CD147 receptor of CAFs, inducing CAF polarization and leading to chemoresistance. Therapeutically, we demonstrate that blocking the S100A8-CD147 pathway can improve chemotherapy efficiency. Prognostically, we found the S100A8 levels in peripheral blood can serve as an indicator of chemotherapy responsiveness. Collectively, our study offers a comprehensive understanding of the molecular mechanisms underlying chemoresistance in esophageal cancer and highlights the potential value of S100A8 in the clinical management of esophageal cancer.

Mesencephalic astrocyte-derived neurotrophic factor ameliorates inflammatory response in polycystic ovary syndrome via inhibiting TLR4-NF-κB-NLRP3 pathway

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder in women of reproductive age, which often leads to female infertility. Chronic inflammation is a significant factor in the development of PCOS. Our study aimed to explore the impact of mesencephalic astrocyte-derived neurotrophic factor (MANF), a scientifically validated anti-inflammatory factor, on 99 diagnosed PCOS patients. We also investigated its effects on PCOS mice induced with dehydroepiandrosterone (DHEA) and KGN cells induced with dihydrotestosterone (DHT). Our findings revealed a decrease in serum MANF levels in PCOS patients, which were negatively associated with serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels. The administration of recombinant human MANF (rhMANF) in PCOS mice demonstrated a decrease in pro-inflammatory cytokines and monocytes/macrophages in both peripheral blood and ovarian tissues. Furthermore, the inclusion of rhMANF notably ameliorated DHEA-induced ovarian dysfunction and fibrosis by negatively regulating the toll-like receptor 4 (TLR4)-nuclear factor kappa B (NF-κB)-NLR family, pyrin domain containing protein 3 (NLRP3) pathway. Additionally, in vitro experiments showed that the up-regulation of MANF offset DHT-induced inhibition of viability and apoptosis in KGN cells. Collectively, this study highlights the anti-inflammatory properties of MANF in PCOS and suggests its potential as a therapeutic approach for the management of PCOS.

CSF1R inhibition reprograms tumor-associated macrophages to potentiate anti-PD-1 therapy efficacy against colorectal cancer

PD-1 blockade therapy has made great breakthroughs in treatment of multiple solid tumors. However, patients with microsatellite-stable (MSS) colorectal cancer (CRC) respond poorly to anti-PD-1 immunotherapy. Although CRC patients with microstatellite instability (MSI) or microsatellite instability-high (MSI-H) can benefit from PD-1 blockade therapy, there are still some problems such as tumor recurrence. Tumor-associated macrophages (TAMs), most abundant immune components in tumor microenvironment (TME), largely limit the therapeutic efficacy of anti-PD-1 against CRC. The CSF1/CSF1R pathway plays a key role in regulating macrophage polarization, and blocking CSF1R signaling transduction may be a potential strategy to effectively reprogram macrophages and remodel TME. Here, we found that increasing expression of CSF1R in macrophages predicted poor prognosis in CRC cohort. Furthermore, we discovered a novel potent CSF1R inhibitor, PXB17, which significantly reprogramed M2 macrophages to M1 phenotype. Mechanically, PXB17 significantly blocked activation of PI3K/AKT/mTORC1 signaling, resulting in inhibition of cholesterol biosynthesis. Results from 3D co-culture system suggested that PXB17-repolarized macrophages could induce infiltration of CD8+ T lymphocytes in tumors and improve the immunosuppressive microenvironment. In vivo, PXB17 significantly halted CRC growth, with a stronger effect than PLX3397. In particular, PXB17 potently enhanced therapeutic activity of PD-1 mAb in CT-26 (MSS) model and prevented tumor recurrence in MC-38 (MSI-H) model by promoting formation of long-term memory immunity. Our study opens a new avenue for CSF1R in tumor innate and adaptive anti-tumor immunomodulatory activity and suggests that PXB17 is a promising immunotherapy molecule for enhancing the efficacy of PD-1 mAb or reducing tumor recurrence of CRC.

Hepatocytes-derived Prdx1 regulates macrophage phenotypes via TLR4 activation in acute liver injury

Acute liver injury (ALI) is a significant causative factor for multiple hepatic diseases. The excessive inflammatory response triggers proinflammatory immune cells recruitment, infiltration and differentiation, further contributing to inflammatory injuries in liver. As a proinflammatory factor, circulating Peroxiredoxin 1 (Prdx1) is elevated in ALI patients and mice. In this study, through carbon tetrachloride (CCl4) and cecal puncture and ligation (CLP)-induced liver injury mice model, we found hepatocytes-derived Prdx1 expression was increased in ALI. After AAV8-Prdx1-mediated Prdx1 knockdown, CCl4 and CLP-induced ALI was alleviated, along with the reduced proinflammatory cytokines, suppressed myeloid cells recruitment, decreased proportions of hepatic macrophages and neutrophils, restrained proinflammatory macrophage differentiation and infiltration. Mechanistically, hepatocyte-derived Prdx1 regulated macrophages through paracrine activation of the TLR4 signal. Our data support the immune and inflammatory regulatory role of Prdx1 in ALI pathological process to suggest its potential therapeutic application and clinical value.