Sensitivity Of Cells Research Articles

NPC1 links cholesterol trafficking to microglial morphology via the gastrosome.

Microglia play important roles in brain development and homeostasis by removing dying neurons through efferocytosis. Morphological changes in microglia are hallmarks of many neurodegenerative conditions, such as Niemann-Pick disease type C. Here, NPC1 loss causes microglia to shift from a branched to an ameboid form, though the cellular basis and functional impact of this change remain unclear. Using zebrafish, we show that NPC1 deficiency causes an efferocytosis-dependent expansion of the microglial gastrosome, a collection point for engulfed material. In vivo and in vitro experiments on microglia and mammalian macrophages demonstrate that NPC1 localizes to the gastrosome, and its absence leads to cholesterol accumulation in this compartment. NPC1 loss and neuronal cell death synergistically affect gastrosome size and cell shape, increasing the sensitivity of NPC1-deficient cells to neuronal cell death. Finally, we demonstrate conservation of cholesterol accumulation and gastrosome expansion in NPC patient-derived fibroblasts, offering an interesting target for further disease investigation.

Deciphering MOSPD1's impact on breast cancer progression and therapeutic response.

Motile Sperm Domain-Containing Protein 1 (MOSPD1) has been implicated in breast cancer (BC) pathophysiology, but its exact role remains unclear. This study aimed to assess MOSPD1 expression levels in BC versus normal tissues and investigate its diagnostic potential. MOSPD1 expression was analyzed in BC and normal tissues, with Receiver Operating Characteristic analysis for diagnostic evaluation. Validation was performed using immunohistochemistry. Functional studies included tumor growth assays, MOSPD1 suppression and overexpression experiments, and testing BC cell responses to anti-PD-L1 therapy. MOSPD1 expression was significantly higher in BC samples than normal tissues, correlating with poor clinical outcomes in BC patients. MOSPD1 suppression inhibited tumor growth, while overexpression accelerated it. Silencing MOSPD1 enhanced BC cell sensitivity to anti-PD-L1 therapy and decreased Th2 cell activity. In vivo experiments supported these findings, showing the impact of MOSPD1 on tumor growth and response to therapy. Elevated MOSPD1 levels in BC suggest its potential as a biomarker for adverse outcomes. Targeting MOSPD1, particularly with anti-PD-L1 therapy, may effectively inhibit BC tumor growth and modulate immune responses. This study emphasizes the significance of MOSPD1 in BC pathophysiology and highlights its promise as a therapeutic target.

Highly sensitive reporter cell line for detection of interferon types I-III and their neutralization by antibodies.

Interferons (IFNs) are a critical component of innate immune defenses and limit viral disease severity. To advance studies on IFNs and their neutralization by pathogenic autoantibodies, we generated a Renilla luciferase-based reporter cell line capable of detecting the activities of IFN-Is, IFN-II, and IFN-IIIs. The reporter cell line exhibits a 125- to 2000-fold higher sensitivity to IFNs than a commonly used alternative biological reporter system and allows for a rapid and simple live-cell workflow for detecting low titer amounts of neutralizing anti-IFN antibodies.

Interleukin-2 improves insulin sensitivity through hypothalamic sympathetic activation in obese mice.

IL-2 regulates T cell differentiation: low-dose IL-2 induces immunoregulatory Treg differentiation, while high-dose IL-2 acts as a potent activator of cytotoxic T cells and NK cells. Therefore, high-dose IL-2 has been studied for use in cancer immunotherapy. We aimed to utilize low-dose IL-2 to treat inflammatory diseases such as obesity and insulin resistance, which involve low-grade chronic inflammation. Systemic administration of low-dose IL-2 increased Treg cells and decreased inflammation in gonadal white adipose tissue (gWAT), leading to improved insulin sensitivity in high-fat diet-fed obese mice. Additionally, central administration of IL-2 significantly enhanced insulin sensitivity through the activation of the sympathetic nervous system. The sympathetic signaling induced by central IL-2 administration not only decreased interferon γ (IFNγ) + Th1 cells and the expression of pro-inflammatory cytokines, including Il-1β, Il-6, and Il-8, but also increased CD4 + CD25 + FoxP3 + Treg cells and Tgfβ expression in the gWAT of obese mice. These phenomena were accompanied by hypothalamic microgliosis and activation of pro-opiomelanocortin neurons. Furthermore, sympathetic denervation in gWAT reversed the enhanced insulin sensitivity and immune cell polarization induced by central IL-2 administration. Overall, we demonstrated that IL-2 improves insulin sensitivity through two mechanisms: direct action on CD4 + T cells and via the neuro-immune axis triggered by hypothalamic microgliosis.

Defining the role of Tip60 in the DNA damage response of glioma cell lines

Purpose Glioblastomas are resistant to conventional therapies, including radiotherapy. Our previous study proved that epigenetic regulation influences the radiation response of glioma cells. This study evaluated the role of the acetyltransferase Tip60 on the radiation response. Material and Methods Tip60 expression was down-regulated by transfecting specific siRNA’s in A7 and MO59K cells with high and low expression of Tip60, respectively, and its effect on survival was assessed. DNA repair was analyzed by foci scoring (γH2AX, Rad51, 53BP1, pATM). The interaction of Tip60 with ATM and DNA-PK was investigated using the specific inhibitors KU55933 and NU7441, respectively. Results Knockdown of Tip60 significantly (p < .001) reduced survival in both cell lines, but the effect was more pronounced in A7 cells. ATMi and DNA-PKi significantly reduced the surviving fraction following irradiation. However, no further effect of siTip60 on the radiosensitivity of ATMi treated A7 cells was observed. In contrast, DNA-PKi effectively enhanced the sensitizing effect of siTip60. Mechanistically, siTip60 reduced the number of initial Rad51 and ATM foci formation after irradiation and prevented their dissolution at 24 h. siTip60 had no impact on the formation of 53BP1 and γH2AX foci and did not further affect these end-points if combined with ATMi or DNA-PKi. Conclusions Downregulation of Tip60 enhances the radiation sensitivity of both glioma cells and markedly elevates the radiation sensitivity when combined with DNA-PKi. Therefore, treatment with DNA-PK inhibitors represents a promising approach to augment the radiation sensitivity of glioma cell lines with deficient Tip60 activity in a synergistic manner.

Triple Combination of Entinostat, a Bromodomain Inhibitor, and Cisplatin Is a Promising Treatment Option for Bladder Cancer

Background/Objectives. Cisplatin is part of the first-line treatment of advanced urothelial carcinoma. Cisplatin resistance is a major problem but may be overcome by combination treatments such as targeting epigenetic aberrances. Here, we investigated the effect of the class I HDACi entinostat and bromodomain inhibitors (BETis) on the potency of cisplatin in two pairs of sensitive and cisplatin-resistant bladder cancer cell lines. Cisplatin-resistant J82cisR and T24 LTT were 3.8- and 24-fold more resistant to cisplatin compared to the native cell lines J82 and T24. In addition, a hybrid compound (compound 20) comprising structural features of an HDACi and a BETi was investigated. Results. We found complete (J82cisR) or partial (T24 LTT) reversal of chemoresistance upon combination of entinostat, JQ1, and cisplatin. The same was found for the BETis JQ35 and OTX015, both in clinical trials, and for compound 20. The combinations were highly synergistic (Chou Talalay analysis) and increased caspase-mediated apoptosis accompanied by enhanced expression of p21, Bim, and FOXO1. Notably, the combinations were at least 4-fold less toxic in non-cancer cell lines HBLAK and HEK293. Conclusions. The triple combination of entinostat, a BETi, and cisplatin is highly synergistic, reverses cisplatin resistance, and may thus serve as a novel therapeutic approach for bladder cancer.

Reprogramming the Tumor Immune Microenvironment Through Activatable Photothermal Therapy and GSH depletion Using Liposomal Gold Nanocages to Potentiate Anti-Metastatic Immunotherapy.

Cancer immunotherapy offers significant clinical benefits for patients with advanced or metastatic tumors. However, immunotherapeutic efficacy is often hindered by the tumor microenvironment's high redox levels, leading to variable patient outcomes. Herein, a therapeutic liposomal gold nanocage (MGL) is innovatively developed based on photo-triggered hyperthermia and a releasable strategy by combining a glutathione (GSH) depletion to remodel the tumor immune microenvironment, fostering a more robust anti-tumor immune response. MGL comprises a thermosensitive liposome shell and a gold nanocage core loaded with maleimide. The flexible shell promotes efficient uptake by cancer cells, enabling targeted destruction through photothermal therapy while triggering immunogenic cell death and the maturation of antigen-presenting cells. The photoactivated release of maleimide depletes intracellular GSH, increasing tumor cell sensitivity to oxidative stress and thermal damage. Conversely, GSH reduction also diminishes immunosuppressive cell activity, enhances antigen presentation, and activates T cells. Moreover, photothermal immunotherapy decreases elevated levels of heat shock proteins in tumor cells, further increasing their sensitivity to hyperthermia. In summary, MGL elicited a robust systemic antitumor immune response through GSH depletion, facilitating an effective photothermal immunotherapeutic strategy that reprograms the tumor microenvironment and significantly inhibits primary and metastatic tumors. This approach demonstrates considerable translational potential and clinical applicability.

Chlorella-enriched hydrogels protect against myocardial damage and reactive oxygen species production in anin vitroischemia/reperfusion model using cardiac spheroids.

Microalgae have emerged as promising photosynthetic microorganisms for biofabricating advanced tissue constructs, with improved oxygenation and reduced reactive oxygen species production. However, their use in the engineering of human tissues has been limited due to their intrinsic growth requirements, which are not compatible with human cells. In this study, we first formulated alginate-gelatin (AlgGel) hydrogels with increasing densities ofChlorella vulgaris. Then, we characterised their mechanical properties and pore size. Finally, we evaluated their effects on cardiac spheroid (CS) pathophysiological response under control and ischemia/reperfusion (I/R) conditions. Our results showed that the addition ofChlorelladid not affect AlgGel mechanical properties, while the mean pore size significantly decreased by 35% in the presence of the 107cells mL-1microalgae density. Under normoxic conditions, the addition of 107Chlorellacells mL-1significantly reduced CS viability starting from 14 days in. No changes in pore size nor CS viability were measured for hydrogels containing 105and 106Chlorellacells mL-1. In our I/R model, allChlorella-enriched hydrogels reduced cardiac cell sensitivity to hypoxic conditions with a corresponding reduction in reactive oxygen species (ROS) production, as well as protected against I/R-induced reduction in cell viability. Altogether, our results support a promising use ofChlorella-enriched Alg-Gel hydrogels for cardiovascular tissue engineering.&#xD.

Aurantio‑obtusin regulates lipogenesis and ferroptosis of liver cancer cells through inhibiting SCD1 and sensitizing RSL3.

Ferroptosis, characterized by iron‑mediated non‑apoptotic cell death and alterations in lipid redox metabolism, has emerged as a critical process implicated in various cellular functions, including cancer. Aurantio‑obtusin (AO), a bioactive compound derived from Cassiae semen (the dried mature seeds of Cassie obtusifolia L. or Cassia toral L.), has anti‑hyperlipidemic and antioxidant properties; however, to the best of our knowledge, the effect of AO on liver cancer cells remains unclear. The Cell Counting Kit‑8, EdU staining and migration assays were employed to assess the anti‑liver cancer activity of AO. Intracellular levels of glutathione peroxidase 4 protein and lipid peroxidation were measured as indicators of ferroptotic status. Immunohistochemical analyses, bioinformatics analyses and western blotting were conducted to evaluate the potential of stearoyl‑CoA desaturase 1 (SCD1) in combination with ferroptosis inducers for the personalized treatment of liver cancer. The present study revealed that AO significantly inhibited the proliferation of liver cancer cells in vitro and in vivo. Mechanistically, AO inhibited AKT/mammalian target of rapamycin (mTOR) signaling, suppressed sterol regulatory element‑binding protein 1 (SREBP1) expression, and downregulated fatty acid synthase expression, thereby inhibiting de novo fatty acid synthesis. Further investigations demonstrated that AO suppressed glutathione peroxidase 4 protein expression through the nuclear factor erythroid 2‑related factor 2/heme oxygenase‑1 pathway, induced ferroptosis in liver cancer cells, and simultaneously inhibited lipogenesis by suppressing SCD1 expression through the AKT/mTOR/SREBP1 pathway. Consequently, this increased the sensitivity of liver cancer cells to the ferroptosis inducer RSL3. Additionally, the enhanced effects of AO and RSL3, which resulted in significant tumor suppression, were confirmed in a xenograft mouse model. In conclusion, the present study demonstrated that AO induced ferroptosis, downregulated the expression of SCD1 and enhanced the sensitivity of liver cancer cells to the ferroptosis inducer RSL3. The synergistic use of AO and a ferroptosis inducer may have promising therapeutic effects in liver cancer cells.

Implications of TRPM3 and TRPM8 for sensory neuron sensitisation

Abstract Sensory neurons serve to receive and transmit a wide range of information about the conditions of the world around us as well as the external and internal state of our body. Sensitisation of these nerve cells, i.e. becoming more sensitive to stimuli or the emergence or intensification of spontaneous activity, for example in the context of inflammation or nerve injury, can lead to chronic diseases such as neuropathic pain. For many of these disorders there are only very limited treatment options and in order to find and establish new therapeutic approaches, research into the exact causes of sensitisation with the elucidation of the underlying mechanisms and the identification of the molecular components is therefore essential. These components include plasma membrane receptors and ion channels that are involved in signal reception and transmission. Members of the transient receptor potential (TRP) channel family are also expressed in sensory neurons and some of them play a crucial role in temperature perception. This review article focuses on the heat-sensitive TRPM3 and the cold-sensitive TRPM8 (and TRPA1) channels and their importance in sensitisation of dorsal root ganglion sensory neurons is discussed based on studies related to inflammation and injury- as well as chemotherapy-induced neuropathy.

MG132-mediated Suppression of the Ubiquitin-proteasome Pathway Enhances the Sensitivity of Endometrial Cancer Cells to Cisplatin.

Tumor cell resistance to cisplatin is a common challenge in endometrial cancer chemotherapy, stemming from various mechanisms. Targeted therapies using proteasome inhibitors, such as MG132, have been investigated to enhance cisplatin sensitivity, potentially offering a novel treatment approach. The aim of this study was to investigate the effects of MG132 on cisplatin sensitivity in the human endometrial cancer (EC) cell line RL95-2, focusing on cell proliferation, apoptosis, and cell signaling. Human endometrial cancer RL95-2 cells were exposed to MG132, and cell viability was assessed in a dose-dependent manner. The study evaluated the effect of MG132 on cisplatin-induced proliferation inhibition and apoptosis, correlating with caspase-3 activation and reactive oxygen species (ROS) upregulation. Additionally, we examined the inhibition of the ubiquitin-proteasome system and the expression of pro-inflammatory cytokines IL-1β, IL-6, IL-8, and IL-13 during MG132 and cisplatin co-administration. MG132 exposure significantly reduced cell viability in a dose-dependent manner. It augmented cisplatin- induced proliferation inhibition and enhanced apoptosis, correlating with caspase-3 activation and ROS upregulation. Molecular analysis revealed a profound inhibition of the ubiquitin-proteasome system. MG132 also significantly increased the expression of cisplatin-induced pro-inflammatory cytokines, suggesting a transition from chronic to acute inflammation. MG132 enhances the therapeutic efficacy of cisplatin in human EC cells by suppressing the ubiquitin- proteasome pathway, reducing cell viability, enhancing apoptosis, and shifting the inflammatory response. These findings highlighted the potential of MG132 as an adjuvant in endometrial cancer chemotherapy. Further research is needed to explore detailed mechanisms and clinical applications of this combination therapy.

Groenlandicine enhances cisplatin sensitivity in cisplatin-resistant osteosarcoma cells through the BAX/Bcl-2/Caspase-9/Caspase-3 pathway

Groenlandicine is a protoberberine alkaloid isolated from Coptidis Rhizoma, a widely used traditional Chinese medicine known for its various biological activities. This study aims to validate groenlandicine’s effect on both cisplatin-sensitive and cisplatin-resistant osteosarcoma (OS) cells, along with exploring its potential molecular mechanism.The ligand-based virtual screening (LBVS) method and molecular docking were employed to screen drugs. CCK-8 and FCM were used to measure the effect of groenlandicine on the OS cells transfected by lentivirus with over-expression or low-expression of TOP1. Cell scratch assay, CCK-8, FCM, and the EdU assay were utilized to evaluate the effect of groenlandicine on cisplatin-resistant cells. WB, immunofluorescence, and PCR were conducted to measure the levels of TOP1, Bcl-2, BAX, Caspase-9, and Caspase-3. Additionally, a subcutaneous tumor model was established in nude mice to verify the efficacy of groenlandicine.Groenlandicine reduced the migration and proliferation while promoting apoptosis in OS cells, effectively damaging them. Meanwhile, groenlandicine exhibited weak cytotoxicity in 293T cells. Combination with cisplatin enhanced tumor-killing activity, markedly activating BAX, cleaved-Caspase-3, and cleaved-Caspase-9, while inhibiting the Bcl2 pathway in cisplatin-resistant OS cells. Moreover, the level of TOP1, elevated in cisplatin-resistant OS cells, was down-regulated by groenlandicine both in vitro and in vivo. Animal experiments confirmed that groenlandicine combined with cisplatin suppressed OS growth with lower nephrotoxicity.Groenlandicine induces apoptosis and enhances the sensitivity of drug-resistant OS cells to cisplatin via the BAX/Bcl-2/Caspase-9/Caspase-3 pathway. Groenlandicine inhibits OS cells growth by down-regulating TOP1 level.Therefore, groenlandicine holds promise as a potential agent for reversing cisplatin resistance in OS treatment.

GAD1 ameliorates glioma progression through regulating cuproptosis via RAS/MAPK pathway.

Glioma represents a primary malignant tumor occurring in the central nervous system. Glutamate decarboxylase (GAD1) plays a significant role in tumor development; however, its function of GAD1 and underlying mechanisms in glioma progression remain unclear. Differentially expressed genes (DEGs) obtained from the GSE12657 and GSE15209 datasets that intersected with cuproptosis-related genes and pivot genes were identified using comprehensive bioinformatics methods. The elesclomol (ES) treatment was used to induce cuproptosis in U251 cells, which was validated by detecting intracellular copper levels and cuproptosis marker expression. Lentivirus-mediated gene overexpression was performed to explore the effects of GAD1 using functional assays in vitro and in a mouse xenograft model. The RAS agonist ML098 was used to verify the effect of GAD1 on the RAS/MAPK pathway in glioma cells. A total of 87 cuproptosis-related DEGs and seven hub genes were obtained, with five genes upregulated and two were downregulated in gliomas. Overexpression of GAD1 inhibited proliferation, invasion, and migration, promoted apoptosis of glioma cells, and suppressed tumorigenesis in vivo. In addition, GAD1 overexpression enhanced the sensitivity of glioma cells to cuproptosis. Additionally, ML098 treatment attenuated the inhibitory effect of GAD1 overexpression on the malignant phenotype of ES-treated cells. GAD1 plays an anti-oncogenic role in glioma by regulating apoptosis via inhibition of the RAS/MAPK pathway.

Combined inhibition of MET and VEGF enhances therapeutic efficacy of EGFR TKIs in EGFR-mutant non-small cell lung cancer with concomitant aberrant MET activation

Abstract Background Aberrant activation of mesenchymal epithelial transition (MET) has been considered to mediate primary and acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC). However, mechanisms underlying this process are not wholly clear and the effective therapeutic strategy remains to be determined. Methods The gefitinib-resistant NSCLC cell lines were induced by concentration increase method in vitro. Western blot and qPCR were used to investigate the relationship between MET and vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) signaling pathway. Double luciferase reporter gene and co-immunoprecipitation were used to further reveal the regulation mechanism between MET and VEGF/VEGFR2. The effect of combined inhibition of MET and VEGF/VEGFR2 signaling pathway on the therapeutic sensitivity of EGFR-TKI in gefitinib resistant cell lines with MET aberration was verified ex vivo and in vivo. Results We successfully obtained two gefitinib-resistant NSCLC cell lines with EGFR mutation and abnormal activation of MET. We observed that MET formed a positive feedback loop with the VEGF/VEGFR2 signaling, leading to persistent downstream signaling activation. Specifically, MET up-regulated VEGFR2 expression in a MAPK/ERK/ETS1-dependent manner, while VEGF promoted physical interaction between VEGFR2 and MET, thereby facilitating MET phosphorylation. A MET inhibitor, crizotinib, combined with an anti-VEGF antibody, bevacizumab, enhanced the sensitivity of NSCLC cells to gefitinib and synergistically inhibited the activation of downstream signaling in vitro. Dual inhibition of MET and VEGF combined with EGFR TKIs markedly restrained tumor growth in both human NSCLC xenograft models and in an EGFR/MET co-altered case. Conclusions Our work reveals a positive feedback loop between MET and VEGF/VEGFR2, resulting in continuous downstream signal activation. Combined inhibition of MET and VEGF/VEGFR2 signaling pathway may be beneficial for reversing EGFR TKIs resistance.

Aberrant activation of a miR-101–UBE2D1 axis contributes to the advanced progression and chemotherapy sensitivity in human hepatocellular carcinoma

AbstractChemotherapeutic drugs, such as cisplatin (cis-dichlorodiamineplatinum [II], cDDP) and 5-fluorouracil (5Fu), are widely used in transarterial chemoembolization (TACE), which is a standard therapy for patients with hepatocellular carcinoma (HCC). Chemoresistance is a major cause of TACE treatment failure in HCC patients. Our previous studies have identified the expression levels of miR-101 responsive genes, such as EED, EZH2, STMN1 and JUNB, exhibit significant correlation with the occurrence and progression of HCC, while the role of miR-101 responsive gene signatures in the chemoresistance of HCC treatment remains unclear. In this study, we identified ubiquitin-coupled enzyme E2D1 (UBE2D1) as a crucial regulatory factor in the chemoresistance of HCC, which is a direct target of miR-101 and exhibits significant correlation with miR-101-responsive gene signatures. The bioinformatics analysis showed the expression of UBE2D1 was significantly increased in HCC tissues and was closely correlated with the poor prognosis. In addition, we analyzed the role of miR-101/UBE2D1 axis in regulating chemo-sensitive of HCC cells. Our results showed that miR-101 increases the DNA damage and apoptosis of HCC cells by inhibiting the expression of UBE2D1, which in turn increases the sensitivity of HCC cells to cDDP and 5Fu both in vitro and in vivo. Therefore, simultaneous assessment of miR-101 and UBE2D1 expression levels might provide an effective approach in preselecting HCC patients with survival benefit from TACE treatment. Moreover, further elucidation of the underlying molecular mechanisms of the miR-101/UBE2D1 axis could provide novel insight for targeted therapy of HCC.

7232 Direct m6A mRNA-Seq in Endocrine- Resistant and Sensitive Breast Cancer Cells

7232 Direct m6A mRNA-Seq in Endocrine- Resistant and Sensitive Breast Cancer Cells

Sensitive Detection and Cell Imaging of Ca2+ Based on a "Turn-On" Schiff Base Fluorescent Probe.

Ca2+ ion as a second messenger in signaling pathway plays many vital roles in many biological phenomena. Thus, it is of significance for developing effective probes to detect Ca2+ ion specifically. Herein, a new Schiff base fluorescent probe FPH, fluorescein monoaldehyde (2-aminomethylpyridine) hydrazone, was designed and synthesized to identify Ca2+ in DMSO aqueous solution. The probe FPH revealed significant responses to Ca2+ with a fluorescence enhancement at 540 nm, exhibiting an evident fluorescence change from ultraweak luminescence to bright green. Otherwise, the FPH displayed a good linear range of 0.67 × 10-6 to 3.33 × 10-6 mol/L with a lower detection limit at 7.02 × 10-8 mol/L. The probe FPH were further successfully utilized to detect Ca2+ in living cells by an increased bright green fluorescence.

Runx2 silencing sensitized human renal cell carcinoma cells to ABT-737 apoptosis

The prognostic value of Runt-related transcription factor 2 (Runx2) and its involvement in cell growth and motility have been reported in patients diagnosed with renal cell carcinoma (RCC). Since Runx2 may have the potential to be a target for the purpose of antitumor intervention, there is an urgent need to gain insight into its oncogenic properties. Using human 786-O, Caki-1 and ACHN RCC cells as models, the silencing of cellular Runx2 expression brought about a reduction in cyclin D1 and β-catenin expression, cell growth and migration without any significant cell death. Runx2-silenced cells turned into apoptosis vulnerable in the presence of ABT-737, a BH3 mimetic Bcl-2 inhibitor. Data from biochemical and molecular studies have revealed a positive correlation between Runx2 expression and Akt phosphorylation, Mcl-1 expression, and fibronectin expression. Results of genetic silencing studies have indicated the potential involvement of Mcl-1 and fibronectin in the decision of RCC cell ABT-737 resistance and sensitivity. The regulatory roles of the PI3K/Akt axis in the expression of Mcl-1 and fibronectin were suggested by means of the results taken from experiments involving pharmacological study of the PI3K/Akt. Since overexpression and prognostic roles of Runx2, activated Akt, Mcl-1, fibronectin, cyclin D1, and β-catenin have been revealed in RCC, it is important to explore the precise mechanisms underlying Runx2 oncogenic effects. Although the linking details between Runx2 and PI3K/Akt have yet to be identified, our findings suggest that Mcl-1 and fibronectin are downstream effectors of Runx2 via a regulatory axis of the PI3K/Akt and their promotion of cell growth, migration, and ABT-737 resistance in RCC cells.

N6-methyladenosine-modified TRIM37 augments sunitinib resistance by promoting the ubiquitin-degradation of SmARCC2 and activating the Wnt signaling pathway in renal cell carcinoma

Tripartite motif-containing 37 (TRIM37) is reportedly a key member of the superfamily of TRIM proteins. Emerging evidence underscores the close association between dysregulated TRIM37 expression and the progression of various human malignancies. However, the precise biological functions and regulatory mechanisms of TRIM37 remain elusive. This study aimed to elucidate the impact of TRIM37 on the chemotherapy sensitivity of renal cell carcinoma (RCC) and uncover its specific molecular regulatory role. Using RT-qPCR and western blot assays, we assessed TRIM37 expression in both RCC patients and RCC cells. Through in vitro and in vivo experiments, we investigated the effects of TRIM37 silencing and overexpression on RCC cell proliferation, stemness capacity, and chemotherapy sensitivity using colony formation and sphere formation assays. Additionally, a co-immunoprecipitation (Co-IP) experiment was conducted to explore putative interacting proteins. Our results revealed elevated TRIM37 expression in both RCC patient tumor tissues and RCC cells. Functional experiments consistently demonstrated that TRIM37 silencing reduced proliferation and stemness capacity while enhancing chemotherapy sensitivity in RCC cells. Furthermore, we discovered that TRIM37 mediates the degradation of SMARCC2 via ubiquitin-proteasome pathways, thereby further activating the Wnt signaling pathway. In conclusion, this study not only sheds light on the biological role of TRIM37 in RCC progression but also identifies a potential molecular target for therapeutic intervention in RCC patients.

ACSL4-mediated lipid rafts prevent membrane rupture and inhibit immunogenic cell death in melanoma

Chemotherapy including platinum-based drugs are a possible strategy to enhance the immune response in advanced melanoma patients who are resistant to immune checkpoint blockade (ICB) therapy. However, the immune-boosting effects of these drugs are a subject of controversy, and their impact on the tumor microenvironment are poorly understood. In this study, we discovered that lipid peroxidation (LPO) promotes the formation of lipid rafts in the membrane, which mediated by Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) impairs the sensitivity of melanoma cells to platinum-based drugs. This reduction primarily occurs through the inhibition of immunogenic ferroptosis and pyroptosis by reducing cell membrane pore formation. By disrupting ACSL4-mediaged lipid rafts via the removal of membrane cholesterol, we promoted immunogenic cell death, transformed the immunosuppressive environment, and improved the antitumor effectiveness of platinum-based drugs and immune response. This disruption also helped reverse the decrease in CD8+ T cells while maintaining their ability to secrete cytokines. Our results reveal that ACSL4-dependent LPO is a key regulator of lipid rafts formation and antitumor immunity, and that disrupting lipid rafts has the potential to enhance platinum-based drug-induced immunogenic ferroptosis and pyroptosis in melanoma. This novel strategy may augment the antitumor immunity of platinum-based therapy and further complement ICB therapy.