Apigenin suppresses epithelial-mesenchymal transition in high glucose-induced retinal pigment epithelial cell by inhibiting CBP/p300-mediated histone acetylation.

Epithelial mesenchymal transition (EMT) is a critical process implicated in the pathogenesis of retinal fibrosis and the exacerbation of diabetic retinopathy (DR) within retinal pigment epithelium (RPE) cells. Apigenin (AP), a potential dietary supplement for managing diabetes and its associated complications, has demonstrated inhibitory effects on EMT in various diseases. However, the specific impact and underlying mechanisms of AP on EMT in RPE cells remain poorly understood. In this study, we have successfully validated the inhibitory effects of AP on high glucose-induced EMT in ARPE-19 cells and diabetic db/db mice. Notably, our findings have identified CBP/p300 as a potential therapeutic target for EMT in RPE cells and have further substantiated that AP effectively downregulates the expression of EMT-related genes by attenuating the activity of CBP/p300, consequently reducing histone acetylation alterations within the promoter region of these genes. Taken together, our results provide novel evidence supporting the inhibitory effect of AP on EMT in RPE cells, and highlight the potential of specifically targeting CBP/p300 as a strategy for inhibiting retinal fibrosis in the context of DR.

Paeoniflorin promotes PPARγ expression to suppress HSCs activation by inhibiting EZH2-mediated histone H3K27 trimethylation.

BACKGROUND: The alleviating effect of paeoniflorin (Pae) on liver fibrosis has been established; however, the molecular mechanism and specific target(s) underlying this effect remain elusive. PURPOSE: This study was to investigate the molecular mechanism underlying the regulatory effect of Pae on hepatic stellate cells (HSCs) activation in liver fibrosis, with a specific focus on the role of Pae in modulating histone methylation modifications. METHODS: The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl4)-induced mice and transforming growth factor ß1 (TGF-ß1)-induced LX-2 cells, respectively. Molecular docking, surface plasmon resonance (SPR), chromatin immunoprecipitation-quantitative real time PCR (ChIP-qPCR) and other molecular biological methods were used to clarify the molecular mechanism of Pae regulating HSCs activation. RESULTS: Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl4-induced mice and LX-2 cells. We demonstrated that the inhibitory effect of Pae on the activation of HSCs was dependent on peroxisome proliferator-activated receptor γ (PPARγ) expression and enhancer of zeste homolog 2 (EZH2). Mechanistically, Pae directly binded to EZH2 to effectively suppress its enzymatic activity. This attenuation leaded to the suppression of histone H3K27 trimethylation in the PPARγ promoter region, which induced upregulation of PPARγ expression. CONCLUSION: This investigative not only sheds new light on the precise targets that underlie the remission of hepatic fibrogenesis induced by Pae but also emphasizes the critical significance of EZH2-mediated H3K27 trimethylation in driving the pathogenesis of liver fibrosis.

Si-Ni-San inhibits hepatic Fasn expression and lipid accumulation in MAFLD mice through AMPK/p300/SREBP-1c axis.

BACKGROUND: Soothing the liver and regulating qi is one of the core ideas of traditional Chinese medicine (TCM) in the treatment of fatty liver. Si-Ni-San (SNS) is a well-known herbal formula in TCM for liver soothing and qi regulation in fatty liver treatment. However, its efficacy lacks modern scientific evidence. PURPOSE: This study was aimed to investigate the impact of SNS on metabolic associated fatty liver disease (MAFLD) in mice and explore the underlying molecular mechanisms, particularly its effects on lipid metabolism in hepatocytes. METHODS: The therapeutic effect of SNS was evaluated using in vivo and in vitro models of high-fat/high-cholesterol (HFHC) diet-induced mice and palmitic acid (PA)-induced hepatocytes, respectively. Molecular biological techniques such as RNA-sequencing (RNA-seq), co-immunoprecipitation (co-IP), and western blotting were employed to elucidate the molecular mechanism of SNS in regulating lipid metabolism in hepatocytes. RESULTS: Our findings revealed that SNS effectively reduced lipid accumulation in the livers of HFHC diet-induced mice and PA-induced hepatocytes. RNA-seq analysis demonstrated that SNS significantly down-regulated the expression of fatty acid synthase (Fasn) in the livers of HFHC-fed mice. Mechanistically, SNS inhibited Fasn expression and lipid accumulation by activating adenosine monophosphate (AMP)-activated protein kinase (AMPK). Activation of AMPK suppressed the activity of the transcriptional coactivator p300 and modulated the protein stability of sterol regulatory element-binding protein-1c (SREBP-1c). Importantly, p300 was required for the inhibition of Fasn expression and lipid accumulation by SNS. Furthermore, SNS activated AMPK by decreasing adenosine triphosphate (ATP) production in hepatocytes. CONCLUSION: This study provided novel evidence on the regulatory mechanisms underlying the effects of SNS on Fasn expression. Our findings demonstrate, for the first time, that SNS exerts suppressive effects on Fasn expression through modulation of the AMPK/p300/SREBP-1c axis. Consequently, this regulatory pathway mitigates excessive lipid accumulation and ameliorates MAFLD in mice.

[Preparation of vitexin albumin nanoparticles and its pharmacokinetic study].

This study aims to prepare vitexin albumin nanoparticles(VT-BSA-NPs) to alleviate the low bioavailability of vitexin(VT) in vivo due to its poor water solubility. VT micro powders were prepared by the antisolvent crystallization method, and the morphology, size, and physicochemical properties of VT micro powders were studied. The results showed that the VT micro powder had a particle size of(187.13±7.15) nm, an approximate spherical morphology, and a uniform size distribution. Compared with VT, the chemical structure of VT micro powders has not changed. VT-BSA-NPs were prepared from VT micro powders by desolvation-crosslinking curing method. The preparation process was screened by single factor test and orthogonal test, and the quality evaluation of the optimal prescription particle size, PDI, Zeta potential, EE, and morphology was performed. The results showed that the average particle size of VT-BSA-NPs was(124.33±0.47) nm; the PDI was 0.184±0.012; the Zeta potential was(-48.83±2.20) mV, and the encapsulation rate was 83.43%±0.39%, all of which met the formulation-related requirements. The morphological results showed that the VT-BSA-NPs were approximately spherical in appearance, regular in shape, and without adhesion on the surface. In vitro release results showed a significantly reduced release rate of VT-BSA-NPs compared with VT, indicating a good sustained release effect. LC-MS/MS was used to establish an analytical method for in vivo analysis of VT and study the plasma pharmacokinetics of VT-BSA-NPs in rats. The results showed that the specificity of the analytical method was good, and the extraction recovery was more than 90%. Compared with VT and VT micro powders, VT-BSA-NPs could significantly increase AUC, MRT, and t_(1/2), which was beneficial to improve the bioavailability of VT.

Essential oil extracted from Quzhou Aurantii Fructus prevents acute liver failure through inhibiting lipopolysaccharide-mediated inflammatory response.

Quzhou Aurantii Fructus (QAF) has a long history as a folk medicine and food for the treatment of liver diseases. While our earlier study provided evidence of hepatoprotective properties contained within the flavonoids and limonins constituents in QAF, the potential preventative effects afforded by essential oil components present within QAF remains enigmatic. In this study, we prepared Quzhou Aurantii Fructus essential oil (QAFEO) and confirmed its anti-inflammatory effects on liver inflammation through experimentation on lipopolysaccharide and D-galactosamine (LPS/D-GalN) induced acute liver failure (ALF) mouse models. Using RNA-sequence (RNA-seq) analysis, we found that QAFEO prevented ALF by systematically blunting the pathways involved in response to LPS and toll-like receptor signaling pathways. QAFEO effectively suppressed the phosphorylation of tank-binding kinase 1 (TBK1), TGF-beta activated kinase 1 (TAK1), interferon regulatory factor 3 (IRF3), and the activation of mitogen activated kinase-like protein (MAPK) and nuclear factor-kappa B (NF-κB) pathways in vivo and in vitro. Importantly, QAFEO substantially reduced myeloid differentiation primary response gene 88 (MyD88)- toll-like receptor 4 (TLR4) interaction levels. Moreover, 8 compounds from QAFEO could directly bind to REAL, TAK1, MyD88, TBK1, and IRF3. Taken together, the results of our study support the notion that QAFEO exerts a hepatoprotective effect through inhibiting LPS-mediated inflammatory response.

Saikosaponin A triggers cell ferroptosis in hepatocellular carcinoma by inducing endoplasmic reticulum stress-stimulated ATF3 expression.

Ferroptosis is a type of nonapoptotic necrotic cell death characterized by iron-dependent lipid peroxidation. Saikosaponin A (SsA), a natural bioactive triterpenoid saponin extracted from Radix Bupleuri, has shown potent antitumor activity against various tumors. However, the underlying mechanism of the antitumor activity of SsA remains unclear. Here, we discovered that SsA induced HCC cell ferroptosis in vitro and in vivo. Using RNA-sequence analysis, we found that SsA mainly affected the glutathione metabolic pathway and inhibited the expression of cystine transporter solute carrier family 7 member 11 (SLC7A11). Indeed, SsA increased intracellular malondialdehyde (MDA) and iron accumulation, while it decreased the levels of reduced glutathione (GSH) in HCC. Deferoxamine (DFO), ferrostatin-1 (Fer-1) and GSH could rescue SsA-induced cell death, whereas Z-VAD-FMK was found ineffective in inhibiting SsA-induced cell death in HCC. Importantly, our result indicated that SsA induced the expression of activation transcription factor 3 (ATF3). SsA-induced cell ferroptosis and suppression of SLC7A11 are dependent on ATF3 in HCC. Moreover, we revealed that SsA induced ATF3 upregulation via activation of endoplasmic reticulum (ER) stress. Taken together, our findings support that ATF3-dependent cell ferroptosis mediated the antitumor effects of SsA, opening the possibility to explore SsA as a ferroptosis inducer in HCC.

Determining a multimodal aging clock in a cohort of Chinese women.

BACKGROUND: Translating aging rejuvenation strategies into clinical practice has the potential to address the unmet needs of the global aging population. However, to successfully do so requires precise quantification of aging and its reversal in a way that encompasses the complexity and variation of aging. METHODS: Here, in a cohort of 113 healthy women, tiled in age from young to old, we identified a repertoire of known and previously unknown markers associated with age based on multimodal measurements, including transcripts, proteins, metabolites, microbes, and clinical laboratory values, based on which an integrative aging clock and a suite of customized aging clocks were developed. FINDINGS: A unified analysis of aging-associated traits defined four aging modalities with distinct biological functions (chronic inflammation, lipid metabolism, hormone regulation, and tissue fitness), and depicted waves of changes in distinct biological pathways peak around the third and fifth decades of life. We also demonstrated that the developed aging clocks could measure biological age and assess partial aging deceleration by hormone replacement therapy, a prevalent treatment designed to correct hormonal imbalances. CONCLUSIONS: We established aging metrics that capture systemic physiological dysregulation, a valuable framework for monitoring the aging process and informing clinical development of aging rejuvenation strategies. FUNDING: This work was supported by the National Natural Science Foundation of China (32121001), the National Key Research and Development Program of China (2022YFA1103700 and 2020YFA0804000), the National Natural Science Foundation of China (81502304), and the Quzhou Technology Projects (2022K46).

Unsymmetrical Phosphodiesters as GPR84 Antagonists with High Blood Exposure for the Treatment of Lung Inflammation.

GPR84 is a proinflammatory G protein-coupled receptor that mediates myeloid immune cell functions. Blocking GPR84 with antagonists is a promising approach for treating inflammatory and fibrotic diseases. Previously, a GPR84 antagonist 604c, with a symmetrical phosphodiester structure, has displayed promising efficacy in a mouse model of ulcerative colitis. However, the low blood exposure resulting from physicochemical properties prevented its uses in other inflammatory diseases. In this study, a series of unsymmetrical phosphodiesters with lower lipophilicity were designed and tested. The representative compound 37 exhibited a 100-fold increase in mouse blood exposure compared to 604c while maintaining in vitro activity. In a mouse model of acute lung injury, 37 (30 mg/kg, po) significantly reduced the infiltration of proinflammatory cells and the release of inflammatory cytokines and ameliorated pathological changes equally or more effectively than N-acetylcysteine (100 mg/kg, po). These findings suggest that 37 is a promising candidate for treating lung inflammation.

GPR84 regulates pulmonary inflammation by modulating neutrophil functions.

Acute lung injury (ALI) is an acute, progressive hypoxic respiratory failure that could develop into acute respiratory distress syndrome (ARDS) with very high mortality rate. ALI is believed to be caused by uncontrolled inflammation, and multiple types of immune cells, especially neutrophils, are critically involved in the development of ALI. The treatment for ALI/ARDS is very limited, a better understanding of the pathogenesis and new therapies are urgently needed. Here we discover that GPR84, a medium chain fatty acid receptor, plays critical roles in ALI development by regulating neutrophil functions. GPR84 is highly upregulated in the cells isolated from the bronchoalveolar lavage fluid of LPS-induced ALI mice. GPR84 deficiency or blockage significantly ameliorated ALI mice lung inflammation by reducing neutrophils infiltration and oxidative stress. Further studies reveal that activation of GPR84 strongly induced reactive oxygen species production from neutrophils by stimulating Lyn, AKT and ERK1/2 activation and the assembly of the NADPH oxidase. These results reveal an important role of GPR84 in neutrophil functions and lung inflammation and strongly suggest that GPR84 is a potential drug target for ALI.

Maternal embryonic leucine zipper kinase in tumor cells and tumor microenvironment: An emerging player and promising therapeutic opportunity.

Maternal embryonic leucine zipper kinase (MELK) is a member of the AMPK (AMP-activated protein kinase) protein family, which is widely and highly expressed in multiple cancer types. Through direct and indirect interactions with other targets, it mediates various cascades of signal transduction processes and plays an important role in regulating tumor cell survival, growth, invasion and migration and other biological functions. Interestingly, MELK also plays an important role in the regulation of the tumor microenvironment, which can not only predict the responsiveness of immunotherapy, but also affect the function of immune cells to regulate tumor progression. In addition, more and more small molecule inhibitors have been developed for the target of MELK, which exert important anti-tumor effects and have achieved excellent results in a number of clinical trials. In this review, we outline the structural features, molecular biological functions, potential regulatory mechanisms and important roles of MELK in tumors and tumor microenvironment, as well as substances targeting MELK. Although many molecular mechanisms of MELK in the process of tumor regulation are still unknown, it is worth affirming that MELK is a potential tumor molecular therapeutic target, and its unique superiority and important role provide clues and confidence for subsequent basic research and scientific transformation.

Cinobufacini retards progression of pancreatic ductal adenocarcinoma through targeting YEATS2/TAK1/NF-κB axis.

BACKGROUND: Cinobufacini, a sterilized hot water extract of dried toad skin, had significant effect against several human cancers. However, there are few studies reporting the effect of cinobufacini on pancreatic cancer. PURPOSE: To investigate the effects of cinobufacini on the progress of pancreatic ductal adenocarcinoma and the underlying mechanisms. METHODS: Cell counting, EdU incorporation and flow Cytometry were performed to evaluate the effect of cinobufacini on cell cycle and growth. MIA-PaCa2 cells were implanted into the nude mice to determine whether cinobufacini represses PDAC progression in vivo. Luciferase reporter assay, western blotting and qPCR were carried out to measure the activity of NF-κB pathway and the alteration of YEATS2 and TAK1. Ectopic gene expression introduced by plasmids was used to verify the molecular mechanism. RESULTS: Our results showed that cinobufacini induced cell cycle arrest and inhibited the growth of PDAC cell in vitro, and repressed MIA-derived PDAC in vivo. Cinobufacini inhibited the phosphorylation of IKK, IκB and NF-κB p65 in PDAC cells. Furthermore, cinobufacini decreased the abundance of intracellular YEATS2 and total TAK1 protein in a time- and dose dependent manner. Ectopic expression of YEATS2 re-elevated the level of TAK1 and phosphorylated IKKα/ß, IκBα and p65 after cinobufacini treatment in PANC-1 cells. CONCLUSION: Cinobufacini retards the growth and progression of PDAC in vitro and in vivo through YEATS2/TAK1/NF-κB axis.

YEATS2 regulates the activation of TAK1/NF-κB pathway and is critical for pancreatic ductal adenocarcinoma cell survival.

The prognosis of pancreatic ductal adenocarcinoma (PDAC) is poor despite diagnostic progress and new chemotherapeutic regimens. Constitutive activation of NF-κB is frequently observed in PDAC. In this study, we found that YEATS2, a scaffolding protein of ATAC complex, was highly expressed in human PDAC. Depletion of YEATS2 reduced the growth, survival, and tumorigenesis of PDAC cells. The binding of YEATS2 is crucial for maintaining TAK1 activation and NF-κB transcriptional activity. Of importance, our results reveal that YEATS2 promotes NF-κB transcriptional activity through modulating TAK1 abundance and directly interacting with NF-κB as a co-transcriptional factor.

Celastrol inhibits TXNIP expression to protect pancreatic ß cells in diabetic mice.

BACKGROUND: Celastrol (CEL) has a great potential in the treatment of a wide variety of metabolic diseases. However, whether CEL protects pancreatic ß cells and its underlying mechanism are not yet clear. PURPOSE: This study investigates to determine the effects of CEL on the pathogenesis of pancreatic ß cells damage. METHODS: C57BLKS/Leprdb (db/db) mice and rat insulinoma INS-1 cell line or mouse J774A.1 cell line were used as in vivo and in vitro models for investigating the protective effect of CEL on pancreatic ß cells under high glucose environment and the related mechanism. The phenotypic changes were evaluated by immunofluorescence, immunohistochemical staining, flow cytometry and the measurement of biochemical indexes. The molecular mechanism was explored by biological techniques such as western blotting, qPCR, ChIP-qPCR, co-immunoprecipitation and lentivirus infection. RESULTS: Our results showed that CEL at the high dose (CEL-H, 0.2 mg/kg) protects db/db mice against increased body weight and blood glucose. CEL-H inhibits pancreatic ß cell apoptosis in db/db mice and high glucose-induced INS-1 cells. CEL-H also reduced IL-1ß production in islet macrophages. The further study found that CEL suppressed TXNIP expression and NLRP3 inflammasome activation in pancreatic ß cells and islet macrophages. Importantly, the inhibitory effect of CEL on pancreatic ß cell apoptosis and IL-1ß production was also dependent on TXNIP. Mechanically, CEL inhibits Txnip transcription by promoting the degradation of ChREBP. CONCLUSION: Celastrol inhibits TXNIP expression to protect pancreatic ß cells in vivo and in vitro. Our research pointed out another mechanism by which celastrol functions under the condition leptin signaling is ineffective.

KSR2-14-3-3ζ complex serves as a biomarker and potential therapeutic target in sorafenib-resistant hepatocellular carcinoma.

BACKGROUND: Kinase suppressor of Ras 2 (KSR2) is a regulator of MAPK signaling that is overactivated in most hepatocellular carcinoma (HCC). We sought to determine the role of KSR2 in HCC pathogenesis. METHODS: We tested the level of KSR2 in HCC tissues and cell lines by tissue microarray, qPCR, and western blotting. Functionally, we determined the effects of KSR2 on the proliferation, migration, and invasion of HCC cells through colony formation assays, scratch assays, transwell migration assays, and xenograft tumor models. Co-immunoprecipitation (co-IP) experiments were used to assess the interaction of phospho-serine binding protein 14-3-3ζ and KSR2, and the effects of this interaction on growth and proliferation of human HCC cells were tested by co-overexpression and knockdown experiments. Additionally, we used flow cytometry to examine whether the KSR2 and 14-3-3ζ interaction conveys HCC resistance to sorafenib. RESULTS: KSR2 was significantly upregulated in HCC tissues and cell lines, and high KSR2 expression associated with poor prognosis in HCC patients. KSR2 knockdown significantly suppressed HCC cell proliferation, migration, and invasion in vitro and in vivo. Mechanistically, co-IP experiments identified that 14-3-3ζ complexed with KSR2, and elevated 14-3-3ζ increased KSR2 protein levels in HCC cells. Importantly, Kaplan-Meier survival analysis showed that patients with both high KSR2 and high 14-3-3ζ expression levels had the shortest survival times and poorest prognoses. Interestingly, HCC cells overexpressing both KSR2 and 14-3-3ζ, rather than either protein alone, showed hyperactivated MAPK signaling and resistance to sorafenib. CONCLUSIONS: Our results provide new insights into the pro-tumorigenic role of KSR2 and its regulation of the MAPK pathway in HCC. The KSR2-14-3-3ζ interaction may be a therapeutic target to enhance the sorafenib sensitivity of HCC.

The complete mitochondrial genome of the Great evening bat Ia io (Chiroptera: Vespertiilionidae) from karst area, Southwestern China.

In this study, the complete mitochondrial genome of Ia io from Guizhou Province, China. The genome was a circular mitochondrial genome of 16689 bp in length, containing 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNA), 2 ribosomal RNA genes (rRNA), and a control region. The average base composition is 32.76% A, 24.59% C, 14.49% G, and 28.16% T. The first complete mitochondrial genome of I. io provides fundamental data for future systematic taxonomic studies of the genus Ia.

Residue Analysis and the Effect of Preharvest Forchlorfenuron (CPPU) Application on On-Tree Quality Maintenance of Ripe Fruit in "Feizixiao" Litchi (Litchi chinensis Sonn.).

Litchi is a highly perishable fruit. Ripe litchi fruit loses quality quickly as they hang on tree, giving a very short hanging life and thus harvest period. This study attempted to explore the roles of cytokinin in regulating fruit ripening and senescence of litchi and examine the possibility of applying cytokinin in "on-tree storage" of the fruit. Exogenous cytokinin, forchlorfenuron (CPPU), was applied at 20 mg L-1 7 weeks after full bloom on litchi (Litchi chinensis cv. Feizixiao) fruit clusters. Color parameters, chlorophylls, anthocyanins, fruit and fruit part weights, total soluble solutes (TSSs), soluble sugars, organic acids, non-anthocyanin flavonoids, ethanol, and also CPPU residue in fruit were traced. CPPU residue was higher but decreased faster in the pericarp than in the aril, where it maintained < 10 µg kg-1. CPPU had no significant effect on fruit weight but tended to increase pericarp weight. The treatment suppressed chlorophyll loss and anthocyanin accumulation in the pericarp, increased non-anthocyanin flavonoids in the aril, but had no significant effects on non-anthocyanin flavonoids in the pericarp and total sugar and organic acids in the aril. As the commercially ripe fruit hanged on tree, TSSs, total sugar, and sucrose decreased with ethanol and acetic acid accumulation in the aril. CPPU significantly suppressed the loss of sucrose and total sugar and the accumulation of ethanol and acetic acid in the aril and inhibited malondialdehyde accumulation in the pericarp of the overripe fruit. Soluble invertase, alcohol dehydrogenase, and pyruvate decarboxylase (PDC) activity and gene expression in the aril were downregulated by CPPU. The results suggest that cytokinin partially suppresses the ripening process in litchi and is effective to slow quality loss in the overripe fruit on tree.

Limonin, an AMPK Activator, Inhibits Hepatic Lipid Accumulation in High Fat Diet Fed Mice.

NAFLD is the most prevalent liver disease in human history. The treatment is still limited yet. In the current study, we reported that limonin inhibited hepatic lipid accumulation and fatty acid synthesis in HFD fed mice. Using AMPK inhibitor and AMPK deficient C. elegans, we revealed the effect was dependent on the activation of AMPK. We found that limonin activated AMPK through inhibition of cellular energy metabolism and increasing ADP:ATP ratio. Furthermore, the treatment of limonin induced AMPK mediated suppression of the transcriptional activity of SREBP1/2. Our study suggests that limonin may a promising therapeutic agent for the treatment of NAFLD.

Current applications and future perspective of CRISPR/Cas9 gene editing in cancer.

Clustered regularly interspaced short palindromic repeats (CRISPR) system provides adaptive immunity against plasmids and phages in prokaryotes. This system inspires the development of a powerful genome engineering tool, the CRISPR/CRISPR-associated nuclease 9 (CRISPR/Cas9) genome editing system. Due to its high efficiency and precision, the CRISPR/Cas9 technique has been employed to explore the functions of cancer-related genes, establish tumor-bearing animal models and probe drug targets, vastly increasing our understanding of cancer genomics. Here, we review current status of CRISPR/Cas9 gene editing technology in oncological research. We first explain the basic principles of CRISPR/Cas9 gene editing and introduce several new CRISPR-based gene editing modes. We next detail the rapid progress of CRISPR screening in revealing tumorigenesis, metastasis, and drug resistance mechanisms. In addition, we introduce CRISPR/Cas9 system delivery vectors and finally demonstrate the potential of CRISPR/Cas9 engineering to enhance the effect of adoptive T cell therapy (ACT) and reduce adverse reactions.

PKCα/ZFP64/CSF1 axis resets the tumor microenvironment and fuels anti-PD1 resistance in hepatocellular carcinoma.

BACKGROUND & AIMS: Despite remarkable advances in treatment, most patients with hepatocellular carcinoma (HCC) respond poorly to anti-programmed cell death 1 (anti-PD1) therapy. A deeper insight into the tolerance mechanism of HCC against this therapy is urgently needed. METHODS: We performed next-generation sequencing, multiplex immunofluorescence, and dual-color immunohistochemistry and constructed an orthotopic HCC xenograft tumor model to identify the key gene associated with anti-PD1 tolerance. A spontaneously tumorigenic transgenic mouse model, an in vitro coculture system, mass cytometry, and multiplex immunofluorescence were used to explore the biological function of zinc finger protein 64 (ZFP64) on tumor progression and immune escape. Molecular and biochemical strategies like RNA-sequencing, chromatin immunoprecipitation-sequencing and mass spectrometry were used to gain insight into the underlying mechanisms of ZFP64. RESULTS: We showed that ZFP64 is frequently upregulated in tumor tissues from patients with anti-PD1-resistant HCC. Elevated ZFP64 drives anti-PD1 resistance by shifting macrophage polarization toward an alternative activation phenotype (M2) and fostering an inhibitory tumor microenvironment. Mechanistically, we primarily demonstrated that protein kinase C alpha (PKCα) directly phosphorylates ZFP64 at S226, leading to its nuclear translocation and the transcriptional activation of macrophage colony-stimulating factor (CSF1). HCC-derived CSF1 transforms macrophages to the M2 phenotype to drive immune escape and anti-PD1 tolerance. Notably, Gö6976, a protein kinase inhibitor, and lenvatinib, a multi-kinase inhibitor, reset the tumor microenvironment and restore sensitivity to anti-PD1 by blocking the PKCα/ZFP64/CSF1 axis. CONCLUSIONS: We propose that the PKCα/ZFP64/CSF1 axis is critical for triggering immune evasion and anti-PD1 tolerance. Inhibiting this axis with Gö6976 or lenvatinib overcomes anti-PD1 resistance in HCC. LAY SUMMARY: Despite remarkable treatment progress, most patients with hepatocellular carcinoma respond poorly to anti-PD1 therapy (a type of immunotherapy). A deeper insight into the tolerance mechanisms to this therapy is urgently needed. Herein, we unravel a previously unexplored mechanism linking tumor progression, macrophage polarization, and anti-PD1 resistance, and offer an attractive novel target for anti-PD1 combination therapy, which may benefit patients with hepatocellular carcinoma.