Goat anti-Mouse IgG (H+L) Secondary Antibody, Alexa Fluor 488

Poly (adenosine 5′-diphosphate-ribose) polymerase inhibitors (PARPi) are increasingly important in the treatment of ovarian cancer. However, more than 40% of BRCA1/2-deficient patients do not respond to PARPi, and BRCA wild-type cases do not show obvious benefit. In this study, we demonstrated that progesterone acted synergistically with niraparib in ovarian cancer cells by enhancing niraparib-mediated DNA damage and death regardless of BRCA status. This synergy was validated in an ovarian cancer organoid model and in vivo experiments. Furthermore, we found that progesterone enhances the activity of niraparib in ovarian cancer through inducing ferroptosis by up-regulating palmitoleic acid and causing mitochondrial damage. In clinical cohort, it was observed that progesterone prolonged the survival of patients with ovarian cancer receiving PARPi as second-line maintenance therapy, and high progesterone receptor expression combined with low glutathione peroxidase 4 (GPX4) expression predicted better efficacy of PARPi in patients with ovarian cancer. These findings not only offer new therapeutic strategies for PARPi poor response ovarian cancer but also provide potential molecular markers for predicting the PARPi efficacy.

Background and aims Increasing evidence indicates that modulating pyroptosis in endothelial cells (ECs) can alleviate atherosclerosis (AS) progression; however, despite reports that nucleolin (NCL) regulates vascular smooth muscle cell proliferation in AS, the potential mechanism by which cell surface NCL mediates pyroptosis in ECs during AS remains poorly understood. Methods AS was induced in ApoE -/- mice by feeding a high-fat diet, after which aortic lesions were evaluated. Pyroptosis, inflammatory status, and NCL expression in ECs of the aortic root were then assessed. The effects of NLRP3 inflammasome inhibition and NCL modulation on atherosclerotic lesion severity in AS mice, as well as on pyroptosis in ox-LDL-stimulated ECs, were systematically investigated. In addition, the mechanistic role of NCL in AS was further explored using approaches including immunoprecipitation-mass spectrometry (IP-MS). Results AS model mice developed severe aortic lesions accompanied by pronounced EC pyroptosis and inflammation, together with elevated NCL expression in ECs of the aortic root. Both inhibition of NLRP3 and NCL knockdown alleviated atherosclerotic lesion severity in ApoE -/- mice and attenuated ox-LDL-induced EC pyroptosis. Mechanistically, cell-surface NCL interacted with RASSF2 via its RNA-binding domain, and suppression of NCL decreased nuclear RASSF2 expression. NCL facilitated the translocation of RASSF2 into the nucleus, thereby exacerbating EC pyroptosis and amplifying inflammatory responses. Conclusions This study demonstrates that, in AS, NCL exacerbates EC pyroptosis and promotes disease progression by facilitating nuclear transport of RASSF2. This study defines the mechanistic roles of NCL in AS, thereby identifying a new molecular pathway and suggesting potential therapeutic targets.

Macrophage M2 polarization plays a pivotal role in breast cancer development. The present study aimed to investigate the interplay of the Leupaxin (LPXN)/HDAC6/EGR2 axis in breast cancer and its impact on macrophage M2 polarization. Our findings indicate that LPXN overexpression in breast cancer tissues correlates with M2 macrophage polarization. To investigate LPXN's potential role, we conducted siRNA-mediated silencing in macrophages. In a breast cancer cell-macrophage co-culture system, LPXN silencing was associated with reduced cancer cell proliferation, decreased M2 polarization markers, and diminished HDAC6 expression. BIOGRD and experimental data suggest a regulatory relationship between LPXN and HDAC6. Notably, HDAC6 inhibition partially reversed the pro-M2 effects of LPXN overexpression. Further mechanistic studies revealed that HDAC6 interacts with EGR2, functioning as its deacetylase and negatively regulating EGR2 expression. EGR2 silencing partially attenuated the anti-M2 effects observed with LPXN knockdown. In murine breast cancer models, LPXN silencing was linked to increased M1 macrophage markers and reduced tumor burden. These findings suggest LPXN may influence breast cancer progression through HDAC6/EGR2-mediated regulation of macrophage polarization. In conclusion, our study demonstrated that the LPXN/HDAC6/EGR2 axis promotes breast cancer progression by augmenting macrophage M2 polarization. Graphical

Background Docetaxel (DTX) resistance reduces therapeutic efficacy in prostate cancer (PCa). Accumulating reports support the role of phytochemicals in the reversal of DTX resistance. This study aimed to determine whether Epimedium brevicornu and Curcuma zedoaria extracts (ECe), specially icariin-curcumol, attenuates DTX resistance and explore their potential mechanisms.Methods Regulatory pathways were predicted between ECe active ingredients and PCa using network pharmacology. DTX-resistant cell LNCaP/R were established based on DTX-sensitive LNCaP, and xenograft models were further established. Active ingredients in ECe by HLPC-MS were identified. The binding of icariin and curcumol to the target was analyzed by molecular docking. Biochemical experiments were applied to determine the possible mechanisms by which Icariin-Curcumol regulates DTX sensitivity.Results Akt1 and the PI3K-Akt signaling pathway were predicted as the primary functional target between drug and PCa. ECe and DTX inhibited xenograft tumor growth, inflammation, cell viability and promoted apoptosis. Icariin and curcumol were detected in ECe, and icariin and curcumol docked with Akt1. ECe, Icariin-Curcumol and DTX downregulated AR, PSA, PI3K, Akt1, mTOR, and HIF-1ɑ. Moreover, ECe, Icariin-Curcumol and DTX increased glucose and PDH, decreased lactic acid, ATP and LDH, and downregulated c-Myc, hnRNPs, VEGF, PFK1, and PKM2. Notably, the anti-PCa effect of DTX was attenuated compared to ECe or Icariin-Curcumol in the LNCaP/R model. The combined effect of Icariin-Curcumol and DTX was superior to that of DTX.Conclusion Our data support that Icariin-Curcumol reverses DTX resistance by inhibiting the PI3K-Akt signaling and the Warburg effect, providing new ideas for improving therapeutic measures for PCa.

Ischemic stroke is a serious health hazard that lacks effective treatment strategies. This study aims to investigate baicalin’s effect on tight junctions and immune cell infiltration after ischemic stroke injury. Rat brain microvascular endothelial cells (BMECs) were treated with OGD/R to establish an in vitro model. Caspase-3, Bax, Bcl-2, zonula occludens-1 (ZO-1), occludin, claudin-5, tumor necrosis factor (TNF)- α , interleukin (IL)-6, inducible nitric oxide synthase (iNOS), Toll-like receptor (TLR) 2, TLR4, and nuclear factor-kappa B (NF- κ B) expressions were detected using qRT-PCR and western blotting. ZO-1, TNF- α , iNOS, IL6, CD31, and ZO-1 expressions were examined using immunofluorescence. A tube formation assay was performed to measure angiogenesis. An ischemia-reperfusion model in rats was established by middle cerebral artery occlusion. The infarct volume was observed using 2,3,5-triphenyltetrazolium chloride staining. TNF- α , iNOS, and IL6 levels in the serum were tested using ELISA. Flow cytometry was performed to examine immune cell inflammatory infiltration. Baicalin had no significant effect on the proliferation of normal BMECs. Baicalin inhibited apoptosis, protected against tight junction injury, and alleviated the inflammatory response in OGD/R-induced BMECs and IR rats, with the highest dose (25 μ g/mL) exerting a superior effect. Baicalin decreased the neurological function score, infarct volume, and brain water content, relieved brain morphological changes, and inhibited immune cell infiltration in vivo . In conclusion, baicalin could reduce BMECs apoptosis, protect tight junctions, and resist immune cell infiltration, thereby alleviating ischemic stroke. Our findings potentially provide a novel treatment strategy for ischemic stroke.

Background: A disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1) is involved in the occurrence and development of myocardial fibrosis. Here, we sought to explore the specific regulatory mechanism of ADAMTS1 in cardiac fibrosis post-myocardial infarction (CFPMI). Methods: Blood samples from patients with myocardial fibrosis were collected. A CFPMI mouse model and in vitro models involving human or mouse cardiac fibroblasts treated with TGF-β1 or Ang II were constructed. ChIP was used to confirm that SMAD2 binds to ADAMTS1, and Co-IP was used to verify the interaction between ADAMTS1 and HDAC6. Cellular models with SMAD2 knockdown, ADAMTS1 regulation, and HDAC6 inhibitor treatment were used to study their roles in fibrosis. Finally, AAV-shRNA-HDAC6 and ADAMTS1 inhibitor effects were verified in vivo. Results: ADAMTS1 levels were higher in myocardial fibrosis patients' serum. Increased ADAMTS1 and p-SMAD2 were found in fibrotic mouse hearts and human cardiac fibroblasts stimulated with fibrotic factors. ChIP validated the binding of SMAD2 to ADAMTS1. Mechanistically, SMAD2 regulated ADAMTS1 expression during TGF-β1-induced fibrosis in human and mouse cardiac fibroblasts. Overexpression of ADAMTS1 enhanced the production of collagen fiber proteins in human and mouse cardiac fibroblasts induced by TGF-β1. Moreover, HDAC6 expression was elevated in CFPMI mouse hearts and ADAMTS1 inhibited HDAC6 to regulate fibrosis. ADAMTS1 interacted with HDAC6 during fibrosis. In vivo, shRNA-HDAC6 and ADAMTS1 inhibitor treatment alleviated myocardial fibrosis and improved cardiac function after CFPMI. Conclusions: Targeting ADAMTS1/HDAC6 alleviated TGF-β1/SMAD2-associated cardiac fibrosis in CFPMI. This study may provide a novel theoretical basis for the treatment of myocardial fibrosis.

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, and metastasis and immunosuppression are responsible for the poor prognosis of OSCC. Previous studies have shown that PARP1 plays a key role in the pathogenesis of OSCC. Therefore, targeting PARP1 may serve as an important research target for the potential treatment of OSCC. Here, we aimed to investigate the role of PARP1 in the tumorigenesis of OSCC and elucidate the key molecular mechanisms of its upstream and downstream regulation in vivo and in vitro. In human OSCC tissues and cells, TLR9 and PD-L1 were highly expressed and PARP1 was lowly expressed. Suppression of TLR9 remarkably repressed CAL27 and SCC9 cell proliferation, migration, and invasion. After co-culture, we found that low expression of TLR9 inhibited PD-L1 expression and immune escape. In addition, TLR9 regulated PD-L1 expression through the PARP1/STAT3 pathway. PARP1 mediated the effects of TLR9 on OSCC cell proliferation, migration, and invasion and immune escape. Additionally, in vivo experiments further verified that TLR9 promoted tumour growth and immune escape by inhibiting PARP1. Collectively, TLR9 activation induced immunosuppression and tumorigenesis via PARP1/PD-L1 signaling pathway in OSCC, providing important insights for subsequent in-depth exploration of the mechanism of OSCC.

Ethnopharmacological relevance Probiotic fermentation is a mild and safe biological method to boost the performance of herbs. Portulaca oleracea L. (PO), with folklore records of purgative, anti-dermatological and anti-epidemic effects, has been demonstrated to possess anti-inflammatory, immunomodulatory, and antioxidant properties. However, the potential of PO for the treatment of atopic dermatitis (AD) has not been sufficiently explored. Aim of study This study aimed to evaluate the therapeutic benefits of PO and fermented Portulaca oleracea L. (FPO) and explore their intrinsic mechanisms. Methods By utilizing 2,4-dinitrofluorobenzene-induced AD mice as a model, the histopathology of the lesions was observed using H&E and toluidine blue staining methods; the levels of immunoglobulin E (Ig E), histamine (HIS), and thymic stromal lymphopoietin (TSLP) in serum were measured using ELISA , whereas, the expression of inflammatory cytokines in skin lesion was measured using ELISA and immunohistochemistry experiments. The expression of tumor necrosis factor-α ( TNF-α ), IKKα , NF-κB mRNA was measured using qPCR; and the expression of TNF-α、p-IKKα, p-IκBα, p-NF-κB was measured using western blotting . Results Both 20 mg/mL PO and FPO alleviated mast cell infiltration and lesion pathology, reduced serum levels of Ig E, HIS and TSLP, down-regulated the expression of AD-related inflammatory cytokines, such as, TNF-α, interferon-γ, and interleukin-4, and increased filaggrin expression. Furthermore, they inhibited the expression of TNF-α, IKKα, and NF-κB genes and TNF-α, p-IKKα, p-NF-κB and p-IκBα proteins associated with the NF-κB signaling pathway. Conclusions PO and FPO has a positive therapeutic potential on AD, indicating that it may be employed as alternative therapies for AD.

Background Bone fracture healing is a multifaceted process that involves different stages and intercellular interactions. In this study, we aimed to investigate the effect of Taohong Siwu decoction (TSD) on bone fracture healing and the underlying mechanisms. Methods First, a mouse model of femur fracture was constructed, and TSD intervention was administered for durations of 7, 14, and 21 days. Following this, immunofluorescence (IF) was employed to evaluate the expression of CD90 (a marker for mesenchymal stem cells [MSCs]), endomucin (Emcn), and CD31. We also treated MSCs with normal serum and 10% TSD-containing serum to investigate the effects of TSD. Molecular docking was applied to verify the binding of active compounds in TSD to pVon Hippel–Lindau (VHL). Additionally, MSCs were treated with paeoniflorin and 2-methoxyestradiol (2-ME2) to explore the effects of paeoniflorin. Subsequently, mouse aortic endothelial cells were extracted and identified. Furthermore, normally cultured MSCs were cocultured with endothelial cells. MSCs were exposed to control serum, 10% TSD-containing serum, and a combination of 10% TSD-containing serum with 2-ME2. Finally, we administered a combination of 2-ME2 over 21 days to evaluate its effects on the fractured mice. Results TSD significantly influenced H-type angiogenesis during the healing process of fractured mice. Compared to the sham group, the model group exhibited lower levels of Emcn, CD90, hypoxia-inducible factor-1 alpha (HIF-1α), and vascular endothelial growth factor (VEGF), while there was an increase in pVHL expression. After 7, 14, and 21 days of TSD intervention, the levels of Emcn, CD90, HIF-1α, VEGF, and pVHL gradually increased, whereas HIF-1α expression decreased. In vitro experiments revealed that TSD enhanced the proliferation and migration of MSCs while inhibiting the ubiquitination of pVHL/HIF-1α. Moreover, ferulic acid, amygdalin, hydroxysafflor yellow A, and paeoniflorin demonstrated a strong affinity for binding with pVHL. Notably, paeoniflorin promoted the proliferation and migration of MSCs through the pVHL/HIF-1α pathway to promote angiogenesis. Furthermore, TSD was found to enhance endothelial angiogenesis in MSCs. In summary, TSD affects H-type angiogenesis and MSCs homing during the healing process of fractured mice through the HIF-1α axis. Conclusions TSD regulated MSC-mediated H-type angiogenesis to accelerate fracture healing through VHL/HIF-1α ubiquitination.

Background Lactate, as a critical byproduct of tumor metabolic reprogramming, plays an important role in DNA damage repair and tumor immune infiltration. This work aims to elucidate the molecular mechanisms by which lactate promotes tumor DNA damage repair (DDR) and subsequent immune evasion. Methods Hepatocellular carcinoma (HCC), lung adenocarcinoma (LUAD), and ovarian cancer (OC) cells with cisplatin-induced DNA damage were treated with lactate at a concentration gradient, Endothelial cell-specific molecule 1 (ESM1) shRNA, ESM1 overexpression plasmid, or the Protein Kinase B (AKT) Serine/Threonine Kinase 1 (Akt1) inhibitor LY294002. Proliferation, apoptosis, and DNA damage levels were assessed using 5-ethynyl-2 ′ -deoxyuridine (EdU) staining, flow cytometry-based apoptosis assay, and comet assay. Western blot (WB), Polymerase Chain Reaction (PCR), and immunofluorescence (IF) were employed to evaluate the effects of lactate on the expression of ESM1, Akt1, and Cyclic GMP-AMP Synthase (cGAS) pathway-related proteins in cancer cells. Xenograft tumor models were established using ESM1 whole-gene knockout mice, and Cluster of Differentiation 8 Positive (CD8+) T cell infiltration and apoptotic levels in tumors were detected via flow cytometry. Immunohistochemistry (IHC) was performed to examine the expression of ESM1, double-stranded DNA (dsDNA), and CD8 in tumor patient samples, followed by correlation analysis. Results This study demonstrates that lactate increases ESM1 mRNA and protein expression in a concentration-dependent manner and reduces DNA damage in tumor cells. Lactate suppresses DDR by activating the Akt1 signaling pathway via ESM1 and further inhibits the cGAS pathway, thereby downregulating the transcription of chemokines and pro-inflammatory factors. In vivo experiments confirm that ESM1 knockout promotes CD8+ T cell infiltration into tumors and induces apoptosis. Analysis of tumor patient samples further validates the negative correlation between ESM1 and CD8+ T cell levels in cancer patients. Conclusion In summary, lactate activates the Akt1-Murine Double Minute 2 (MDM2)-p53 pathway via ESM1 to suppress DDR, while the reduction of DDR-generated dsDNA inactivates the cyclic GMP-AMP synthase–Stimulator of Interferon Genes (cGAS-STING) pathway, thereby inhibiting CD8+ T cell immune infiltration.