Fatty-acid-induced FABP5/HIF-1 reprograms lipid metabolism and enhances the proliferation of liver cancer cells

Research progress of CD73-adenosine signaling regulating hepatocellular carcinoma through tumor microenvironment

Adenosine signaling pathway is a kind of signal regulation hub widely existing in human body, which is involved in a series of physiological processes such as energy supply of body cells. CD73 is a highly concerned signaling protein in purine adenosine pathway, and its role in tumor development and prognosis has been paid more and more attention in recent years, especially in hepatocellular carcinoma (HCC). In this paper, the specific mechanism by which CD73-adenosine signaling regulates tumor microenvironment (TME) of liver cancer tumors was analyzed in detail, highlighting the importance of this pathway as a therapeutic target to combat tumor immunosuppression and enhance the anti-tumor immune response to prevent and treat hepatocellular carcinoma (HCC). In addition, a variety of current targeted therapeutic strategies for adenosine metabolic pathways are summarized, including the development of new drugs in the stage of preclinical research and clinical trials, and the mechanism of action, implementation possibility, and clinical effects of these therapies are discussed. By summarizing the latest scientific research results, in this review, we attempt to paint a panorama of the mechanism of adenosine action in tumor immunotherapy, with the aim to provide a solid theoretical basis and practical guidance for subsequent research and clinical application, ultimately promoting the development of more accurate and efficient tumor immunotherapy.

A Feedback Loop Between Fatty Acid Metabolism and Epigenetics in Clear Cell Renal Carcinoma

Lipid storage and epigenetic dysregulation are key features for clear cell renal carcinoma (ccRCC). However, the interplay between fatty acid metabolism and epigenetics in ccRCC remains to be further demonstrated. Here, the landscape of active enhancers is profiled in paired ccRCC samples and identifies 10171 gain variant enhancer loci (VELs) in the tumor tissues. Experimental validation reveals the enhancers targeting FABP5, FABP6, LPCAT1, MET, SEMA5B, SH3GL1, SNX33, and RHBDF2 are oncogenic. Further studies in organoids and animal models prove FABP5 as an oncogene. HIF-2α and ZNF692 transcription factors regulate FABP5 expression through directly binding to its promoter and enhancer. FABP5 is essential for the lipid droplet formation driven by HIFs and critical for H3K27ac and enhancer activity in ccRCC cells. Thus, the study has identified potential targets for drug design and diagnosis and discovered the function of a feedback loop between epigenetics and lipid metabolism regulated by FABP5 in ccRCC.

CE-MS Metabolomic and LC-MS Proteomic Analyses of Breast Cancer Exosomes Reveal Alterations in Purine and Carnitine Metabolism

A nanosheath-flow capillary electrophoresis mass spectrometry (CE-MS) system with electrospray ionization was used to profile cationic metabolite cargo in exosomes secreted by nontumorigenic MCF-10A and tumorigenic MDA-MB-231 breast epithelial cells. An in-house-produced sheath liquid interface was developed and machined from PEEK to enable nanoflow volumes. Normalization of CE-MS peak areas to the total UV signal was employed to enhance quantitative accuracy and reduce variability. CE-MS-based metabolomics revealed increased purine synthesis intermediates and increased carnitine synthesis metabolites in MDA-MB-231-derived exosomes, with pathway enrichment indicating the activation of de novo purine pathways and upregulation of carnitine metabolism. In addition, nano-LC-MS-based proteomics revealed differential expression of ecto-5'-nucleotidase (NT5E) and mitochondrial aldehyde dehydrogenase (ALDH9A1), demonstrating metabolic alterations in related enzymatic steps. This study demonstrates the application of nanosheath-flow CE-MS for comprehensive and quantitative exosome metabolomics, uncovering metabolic reprogramming in purine and carnitine pathways between normal and cancerous breast cell lines and providing insight into exosome-mediated signaling of breast cancer metabolism.

Fatty acid binding proteins-mediated mitochondrial dysfunction in the development of age-related diseases: A review

Fatty acid-binding proteins (FABPs) act as lipid chaperones and play a role in the pathological processes of various lipid signaling pathways. Mitochondria are crucial for the regulation of lipid metabolism. As an aging marker, lipid-mediated mitochondrial dysfunction has been observed in the etiology of numerous diseases, including neurodegenerative diseases, metabolic syndromes, cardiovascular diseases, and tumorigenesis. Members of the FABP family have been identified to regulate mitochondrial function. Targeting FABPs specifically may provide a promising approach to improve mitochondrial function and treat age-related diseases. This review summarizes the connection between FABPs and mitochondrial function and highlights certain FABPs involved in age-related diseases that hold significant therapeutic promise.

Research advances in traditional Chinese medicine formulae and active components targeting lipid metabolism for hepatocellular carcinoma therapy

Hepatocellular carcinoma (HCC) has a relatively poor prognosis and a high degree of malignancy. However, the therapeutic drugs are limited. In recent years, abnormal lipid metabolism and its important role in HCC has been reported, and emerging studies found that some formulae and active components of traditional Chinese medicine (TCM) can regulate abnormal lipid metabolism in HCC, showing their good application prospects. Therefore, this article summarizes the changes and the roles of lipid metabolites in HCC progression, and discusses the role of formulae and active components of TCM for the treatment of HCC based on their regulation on abnormal lipid metabolism. A deeper understanding of their relationship may help the precise use of these formulae and active components in HCC.

RNF126 Promotes Ovarian Cancer Progression by Reprogramming Lipid Metabolism Through Degradation of ACAP2

Ovarian cancer (OC) primarily arises from heterogeneous malignant epithelial tissue in the ovary, fallopian tube, or peritoneum. Ubiquitin ligase Ring-finger protein 126 (RNF126) was aberrantly expressed in OC. However, its molecular mechanism is unknown. This study investigates the role and mechanism of RNF126 in regulating ArfGAP with coiled-coil, ankyrin repeat, and PH domains 2 (ACAP2) during OC progression. RT-qPCR and Western blot (WB) were used to assess the expression of RNF126, ACAP2, and lipid synthesis-related genes in OC tissues and cells. The proliferation and migration abilities of OC cells were detected by CCK-8 and Transwell assays. Nile red staining was used to detect the lipid accumulation. The interaction between RNF126 and ACAP2 in OC cells was detected using co-immunoprecipitation (Co-IP). The stability of the ACAP2 protein was analyzed using the cycloheximide (CHX) assay. The effect of RNF126 on tumor growth and metastasis in vivo was investigated by detecting tumor volume and size as well as the number of lung nodules. The expression of RNF126 was upregulated in OC tissues and cells, and RNF126 silencing significantly inhibited the proliferation, migration, and lipid accumulation of OC cells. Mechanistically, ACAP2 was identified as a ubiquitination substrate of RNF126, and its expression was negatively regulated by RNF126. Furthermore, RNF126 promoted OC progression both in vitro and in vivo by suppressing ACAP2 protein expression. RNF126 promotes ovarian cancer progression by reprogramming lipid metabolism via degrading ACAP2.

Transcriptomic Analysis of Muscle Satellite Cell Regulation on Intramuscular Preadipocyte Differentiation in Tan Sheep

Intramuscular fat (IMF) content is a key factor influencing meat properties including tenderness, flavor, and marbling. However, the complex molecular mechanisms regulating IMF deposition, especially the interactions between intramuscular preadipocytes (IMAdCs) and skeletal muscle satellite cells (SMSCs), remain unclear. In this study, a direct co-culture system of sheep IMAdCs and SMSCs was used to elucidate their intercellular interactions. RNA sequencing and bioinformatics analyses were performed under monoculture and co-culture conditions for later stages of differentiation. The obtained results showed that SMSCs significantly inhibited the adipogenic capacity of IMAdCs. This was reflected in the co-culture markedly altered gene expression and observations of lipid droplets in our studies, i.e., the PPARG, ACOX2, PIK3R1, FABP5, FYN, ALDOC, PFKM, PFKL, HADH, and HADHB genes were down-regulated in the co-cultured IMAdCs in association with the inhibition of fat deposition, whereas ACSL3, ACSL4, ATF3, EGR1, and IGF1R within the genes upregulated in co-culture IMAdCs were associated with the promotion of lipid metabolism. In addition, GO, KEGG, and ligand-receptor pairing analyses further elucidated the molecular mechanisms of intercellular communication. These findings emphasize the regulatory role of SMSCs on intramuscular preadipocyte differentiation and lipid metabolism, providing a theoretical framework for targeted molecular strategies to improve sheep meat quality.

Effects of FABP5 Expression on Clinicopathological and Survival Characteristics in Digestive System Malignancies: A Systematic Review and Meta-Analysis

BACKGROUND

Digestive system malignancies are a major global health burden, and the role of fatty acid binding protein 5 (FABP5) in these tumors remains controversial.

AIMS

This meta-analysis aimed to evaluate the correlation between FABP5 expression and clinicopathological features, as well as survival outcomes in digestive system malignancies.

MATERIALS AND METHODS

Data from 11 studies (1207 patients) retrieved from PubMed, Embase, Cochrane Library, CNKI, and WanFang were analyzed.

RESULTS

FABP5 overexpression was associated with poorer overall survival (OS), larger tumor size, advanced UICC stage, and increased risk of vascular invasion and lymph node metastasis. Notably, FABP5 overexpression is particularly associated with poorer OS in the subgroup of digestive tract malignancies and larger tumor sizes in the subgroup of Chinese patients.

DISCUSSION

Cellular experiments demonstrated that FABP5 overexpression enhances proliferation, migration, and invasion in hepatocellular carcinoma (Huh7) and gastric cancer (HGC-27) cell lines, while FABP5 knockdown reduces these effects. Mechanistically, FABP5 may drive tumor progression through PPARβ/δ signaling, epithelial-mesenchymal transition induction, angiogenesis regulation, and potential effects on fatty acid metabolism and hypoxia-related pathways.

CONCLUSION

FABP5 overexpression correlates with adverse clinicopathological features and prognosis in digestive system malignancies, suggesting its potential as a biomarker for these tumors. Further research is warranted.

FABP5+ lipid-loaded macrophages process tumour-derived unsaturated fatty acid signal to suppress T-cell antitumour immunity

BACKGROUND & AIMS

Tumour-associated macrophages (TAMs) contribute to hepatocellular carcinoma (HCC) progression. However, while the pro-tumour and immunosuppressive roles of lipid-loaded macrophages are well established, the mechanisms by which lipid metabolism enhances the tumour-promoting effects of TAMs remain unclear.

METHODS

Single-cell RNA sequencing was performed on mouse and human HCC tumour samples to elucidate the landscape of HCC TAMs. Macrophages were stimulated with various long-chain unsaturated fatty acids (UFAs) to assess immunosuppressive molecule expression in vitro. Additionally, in vivo and in vitro studies were conducted using mice with macrophage-specific deficiencies in fatty acid-binding protein 5 (FABP5) or peroxisome proliferator-activated receptor γ (PPARγ).

RESULTS

Single-cell RNA sequencing identified a subpopulation of FABP5+ lipid-loaded TAMs characterized by enhanced immune checkpoint blocker ligands and immunosuppressive molecules in an oncogene-mutant HCC mouse model and human HCC tumours. Mechanistically, long-chain UFAs released by tumour cells activate PPARγ via FABP5, resulting in immunosuppressive properties in TAMs. FABP5 deficiency in macrophages decreases immunosuppressive molecule expression, enhances T cell-dependent antitumour immunity, diminishes HCC growth, and improves immunotherapy efficacy.

CONCLUSIONS

This study demonstrates that UFAs promote tumourigenesis by enhancing the immunosuppressive tumour microenvironment via FABP5-PPARγ signalling and provides a proof-of-concept for targeting this pathway to improve the efficacy of tumour immunotherapy.

IMPACT AND IMPLICATIONS

Despite the role of tumour-associated macrophages (TAMs) in promoting tumour progression being well established, the mechanisms by which lipid metabolism enhances the tumour-promoting effects of TAMs remain unclear. Our study reveals that FABP5-mediated unsaturated fatty acid metabolism in TAMs is crucial for modulating antitumour T-cell immunity and influencing the efficacy of immunotherapy. This finding provides novel insights into the immunomodulatory roles of FABP5+ lipid-loaded TAMs in hepatocellular carcinoma and suggests that targeting FABP5 could offer a new approach to liver cancer treatment.

IRX5 Promoted SREBP1-Mediated de Novo Fatty Acid Synthesis via HMGN4 in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), a prevalent malignant tumour, ranks highly in both morbidity and mortality, and its prevention and treatment need further studies. The transcription factor iroquois homeobox 5 (IRX5) plays an essential role in HCC, whereas little is known about its exact functions and underlying mechanisms in tumour metabolism reprogramming. Besides, as a transcription factor that mainly locates in nuclei, IRX5 lacks a nuclear localisation sequence, which makes uncovering the mechanism of IRX5 translocating into the nuclei of great significance. Here, we first found that both IRX5 and HCC development are highly expressed; IRX5 accelerates de novo fatty acid synthesis and promotes cancer cell proliferation and progression. Moreover, the GST pull-down combined with GC/MS experiments identified an interaction between IRX5 and high-mobility group nucleosomal binding domain 4 (HMGN4). Immunofluorescence analysis showed that IRX5 and HMGN4 colocalised within the nucleus. Coimmunoprecipitation further confirmed their direct interaction. The elevated expression of HMGN4 enhanced the nuclear transport of IRX5. Taken together, our observations suggest that HMGN4 driving IRX5 nuclear translocation promotes HCC development via de novo fatty acid synthesis reprogramming.

Tools to Dissect Lipid Droplet Regulation, Players, and Mechanisms

Spurred by the authors' own recent discovery of reactive metabolite-regulated nexuses involving lipid droplets (LDs), this perspective discusses the latest knowledge and multifaceted approaches toward deconstructing the function of these dynamic organelles, LD-associated localized signaling networks, and protein players. Despite accumulating knowledge surrounding protein families and pathways of conserved importance for LD homeostasis surveillance and maintenance across taxa, much remains to be understood at the molecular level. In particular, metabolic stress-triggered contextual changes in LD-proteins' localized functions, crosstalk with other organelles, and feedback signaling loops and how these are specifically rewired in disease states remain to be illuminated with spatiotemporal precision. We hope this perspective promotes an increased interest in these essential organelles and innovations of new tools and strategies to better understand context-specific LD regulation critical for organismal health.

Oropharyngeal carcinomas induce circulating monocytes to express a TAM-like pro-tumor expression profile that suppresses T-cell proliferation

Introduction

Tumor-associated macrophages (TAMs) recruited from circulating monocytes drive tumor-growth and establish an immunosuppressive tumor microenvironment (TME). Initial events in transition from resting monocytes to TAMs are poorly understood. Here, we report that monocytes from oropharyngeal cancer (OPC) patients and control monocytes treated with OPC-conditioned media (CM) express a repertoire of pro-tumor mediators that is characteristic of TAMs.

Methods

Monocytes were stimulated with OPC cell line CM, analyzed by single-cell RNAseq. Results of select genes were confirmed by qPCR with monocytes and analyzed in OPC tumors vs. clinically normal tissue. OPC spheroids containing control monocytes and T-cells were established, TAM phenotype characterized by flow analysis and qPCR, and T-cell proliferation assessed by flow.

Results

OPC-conditioned media induced multiple pro-tumor genes including CXCL1, CXCL5, CXCL8, SPP1, IL1B, GPNMB, and FABP5. Patient monocytes had higher baseline levels or achieved higher levels after stimulation than control monocytes. A subset of patient monocytes had high baseline levels of CXCL9/-10/-11 expression that resisted downregulation in response to stimulation, a potential sign of a more favorable TME. CXCL9/-10/-11 expression in OPC tumor biopsies compared to clinically normal tissue correlated with patient outcome. Spheroid TAMs derived from control monocytes maintained the pro-tumor repertoire seen with monocytes stimulated by tumor line conditioned media. These TAMs suppress T-cell proliferation. Inhibition of COX-2 or IL1 signaling during differentiation into TAMs partially blocked the suppression of T-cell proliferation.

Conclusion

Targeting the early transition of monocytes into pro-tumor TAMs could be used to develop new therapies for OPC.

FABP5 is a key player in metabolic modulation and NF-κB dependent inflammation driving pleural mesothelioma

Pleural mesothelioma (PM) poses a significant challenge in oncology due to its intricate molecular and metabolic landscape, chronic inflammation, and heightened oxidative stress, which contribute to its notorious resilience and clinical complexities. Despite advancements, the precise mechanisms driving PM carcinogenesis remain elusive, impeding therapeutic progress. Here, we explore the interplay between tumor growth dynamics, lipid metabolism, and NF-κB dysregulation in malignant pleural mesothelioma, shedding light on novel molecular mechanisms underlying its pathogenesis. Our study reveals distinctive growth dynamics in PM cells, characterized by heightened proliferation, altered cell cycle progression, and resistance to apoptosis. Intriguingly, PM cells exhibit increased intracellular accumulation of myristic, palmitic, and stearic acids, suggestive of augmented lipid uptake and altered biosynthesis. Notably, we identify FABP5 as a key player in driving metabolic alterations and inflammation through NF-κB dysregulation in mesothelioma cells, distinguishing them from normal mesothelial cells. Silencing of FABP5 leads to significant alterations in cell dynamics, metabolism, and NF-κB activity, highlighting its potential as a therapeutic target. Our findings unveil a reciprocal relationship between lipid metabolism and inflammation in PM, providing a foundation for targeted therapeutic strategies. Overall, this comprehensive investigation offers insights into the intricate molecular mechanisms driving PM pathogenesis and identifies potential avenues for therapeutic intervention.

The role of lipids in promoting hair growth through HIF-1 signaling pathway

Understanding the underlying mechanisms regulating hair regeneration is crucial, especially given the increasing demand for effective drugs to treat hair loss, which remain not fully elucidated. In the present study, we found that lipid metabolism was attenuated in the scalp tissues of patients with androgenetic alopecia. Lipid supplementation in the culture medium upregulated hair growth-related genes and promoted the proliferation of human dermal papilla cells (DPCs). By using RNA-sequencing analysis and HIF-1α knockdown in DPCs, we found that HIF-1α is a potential candidate that governs lipid-reinforced upregulation of trichogenic genes. Finally, we assessed the hair growth-promoting effects of lipids using in vitro hair follicle organoids and found that lipids accelerated the elongation of hair-shaft-like structures. Our results highlight the importance of lipids in promoting hair growth through HIF-1 signaling, suggesting that this may be a promising target for the treatment of hair loss.

Dose-Dependent PFESA-BP2 Exposure Increases Risk of Liver Toxicity and Hepatocellular Carcinoma

Per- and polyfluoroalkyl substances (PFASs) are persistent and highly bioaccumulative emerging environmental contaminants of concern that display significant toxic and carcinogenic effects. An emerging PFAS is PFESA-BP2, a polyfluoroalkyl ether sulfonic acid found in drinking water and the serum of humans and animals. While PFESA-BP2-induced liver and intestinal toxicity has been demonstrated, the toxicological mechanisms and carcinogenic potential of PFESA-BP2 have remained relatively understudied. Here, we studied how different doses of PFESA-BP2 affect gene activity related to liver toxicity and the risk of liver cancer such as hepatocellular carcinoma (HCC) in mice exposed to PFESA-BP2 once daily through oral gavage for seven days. An analysis of key hepatic pathways suggested increased risk of hepatotoxicity as a result of PFESA-BP2 exposure. Increased oxidative stress response was associated with all concentrations of exposure. Liver toxicity pathways, including PXR/RXR activation and hepatic fibrosis, showed dose-dependent alteration with activation primarily at low doses, suggesting an increased risk of hepatic inflammation and injury. Additionally, an analysis of carcinogenic and HCC-specific pathways suggested PFESA-BP2-induced risk of liver cancer, particularly at low doses. Low-dose PFESA-BP2 exposure (0.03 and 0.3 mg/kg-day) was associated with an increased risk of HCC carcinogenesis, as indicated by the activation of tumor-related and HCC-associated pathways. In contrast, these pathways were inhibited at high doses (3.0 and 6.0 mg/kg-day), accompanied by the activation of HCC-suppressive pathways. The increased risk of HCC development at low doses was mechanistically linked to the activation of signaling pathways such as HIF, EGF, NOTCH4, HGF, and VEGF. Biomarkers linked to liver cancer risk, prognoses, and diagnoses were also identified as a result of exposure. Overall, our findings on liver carcinogenic and hepatotoxic pathway activation patterns suggest that PFESA-BP2 increases the risk of liver toxicity and HCC development, particularly at low doses.

Intrahepatic levels of microbiome-derived hippurate associates with improved metabolic dysfunction-associated steatotic liver disease

OBJECTIVE

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterised by lipid accumulation in the liver and is often associated with obesity and type 2 diabetes. The gut microbiome recently emerged as a significant player in liver metabolism and health. Hippurate, a host-microbial co-metabolite has been associated with human gut microbial gene richness and with metabolic health. However, its role on liver metabolism and homeostasis is poorly understood.

METHODS

We characterised liver biospies from 318 patients with obesity using RNAseq and metabolomics in liver and plasma to derive associations among hepatic hippurate, hepatic gene expression and MASLD and phenotypes. To test a potential beneficial role for hippurate in hepatic insulin resistance, we profile the metabolome of (IHH) using ultra-high-performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-MS/MS), and characterised intracellular triglyceride accumulation and glucose internalisation after a 24 h insulin exposure.

RESULTS

We first report significant associations among MASLD traits, plasma and hepatic hippurate. Further analysis of the hepatic transcriptome shows that liver and plasma hippurate are inversely associated with MASLD, implicating lipid metabolism and regulation of inflammatory responses pathways. Hippurate treatment inhibits lipid accumulation and rescues insulin resistance induced by 24-hour chronic insulin in IHH. Hippurate also improves hepatocyte metabolic profiles by increasing the abundance of metabolites involved in energy homeostasis that are depleted by chronic insulin treatment while decreasing those involved in inflammation.

CONCLUSIONS

Altogether, our results further highlight hippurate as a mechanistic marker of metabolic health, by its ability to improve metabolic homeostasis as a postbiotic candidate.

Fu-Zheng-Li-Fei Recipe (FZLFR) in the treatment of cancer cachexia: Exploration of the efficacy and molecular mechanism based on chemical characterization, experimental research and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

FZLFR was derived from a classic traditional Chinese medicine recipe, the Shiquan-Dabu decoction. FZLFR is commonly used in clinical practice to address muscle loss and associated cancer cachexia. However, the mechanism of by which FZLFR acts in cancer cachexia remains unclear.

AIM

This study aimed to assess the effects and explore the potential mechanism of action of FZLFR in treating cancer cachexia.

METHODS

Cancer cachexia was induced by inoculating Lewis lung carcinoma cells into the right flank of male C57BL/6 mice. The efficacy of FZLFR was evaluated by comparing changes in body weight, tumor mass, food intake, survival time, weight, and cross-sectional area of the gastrocnemius and anterior tibial muscles. Moreover, inflammatory cytokines, such as TNF-α and IL-6, were detected by ELISA. The chemical components of FZLFR were analyzed using ultra-performance liquid chromatography-coupled with time-of-flight mass spectrometry. Network pharmacology analysis was performed to screen the core targets and potential pathways involved in FZLFR treatment of cancer cachexia. Molecular docking was used to analyze the binding ability of the core targets and key compounds. The expression levels of core targets and targets correlated with skeletal muscle atrophy were also assessed using western blotting.

RESULTS

FZLFR enhanced the food intake and survival rate of mice with cancer cachexia. It also alleviated tumor-induced body weight loss, tumor growth, and muscle fiber atrophy in these mice. Additionally, it improved the weight and cross-sectional area of the gastrocnemius and anterior tibial muscles. FZLFR down-regulated the serum levels of TNF-α and IL-6. UPLC-ESI-Q-TOF-MS analysis identified 184 compounds in FZLFR. Network pharmacology analysis predicted that TNF signaling pathway, ErbB signaling pathway and VEGF signaling pathway might be essential in FZLFR action. Molecular docking showed that kaempferol, upafolin, apigenin, and luteolin might play key roles in FZLFR treatment. Moreover, FZLFR decreased MAFBx1, MURF1, NF-κB, TWEAK, MAPK8, and EGFR expression levels. FZLFR enhanced the expression of VEGFA and ESR1, as demonstrated by western blotting.

CONCLUSIONS

FZLFR increased food intake and alleviated muscle atrophy in mice with cancer cachexia. The potential pharmacological mechanisms underlying its anticachexia effects include reducing inflammation, enhancing muscle vascular growth, inhibiting tumor angiogenesis, and modulating estrogen receptors.

MELK prevents radiofrequency ablation-induced immunogenic cell death and antitumor immune response by stabilizing FABP5 in hepatocellular malignancies

BACKGROUND

Radiofrequency ablation (RFA) is an efficient treatment with unlimited potential for liver cancer that can effectively reduce patient mortality. Understanding the biological process related with RFA treatment is important for improving treatment strategy. This study aimed to identify the critical targets for regulating the efficacy of RFA.

METHODS

The RFA treatment in hepatocellular carcinoma (HCC) tumor models in vivo, was analyzed by RNA sequencing technology. The heat treatment in vitro for HCC tumor cells was also constructed to explore the mechanism after RFA treatment in tumor cells. Nanoparticles with high affinity to tumor cells were applied as a new therapy to interfere with the expression of maternal embryonic leucine zipper kinase (MELK).

RESULTS

It was found that RFA treatment upregulated MELK expression, and MELK inhibition promoted RFA efficacy by immunogenic cell death and the antitumor response, including anti-tumoral macrophage polarization and increased CD8+ T cell cytotoxicity in HCC. Mechanically, MELK binds to fatty acid-binding protein 5 (FABP5), and affects its ubiquitination through the K48R pathway to increase its stability, thereby activating protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling axis to weaken the RFA-mediated antitumor effect. In addition, the synthesis of arginylglycylaspartic acid (RGD)-lipid nanoparticles (LNPs) targeting tumor cell-intrinsic MELK enhanced RFA efficacy in HCC.

CONCLUSION

MELK is a therapeutic target by regulating RFA efficacy in HCC, and targeting MELK via RGD-LNPs provides new insight into improving RFA efficacy in HCC clinical treatment and combating the malignant progression of liver cancer.

Diosgenin attenuates nonalcoholic fatty liver disease through mTOR-mediated inhibition of lipid accumulation and inflammation

Excessive hepatic lipid accumulation and inflammatory injury are significant pathological manifestations of nonalcoholic fatty liver disease (NAFLD). Our previous research discovered that diosgenin, a natural steroidal saponin derived from Chinese herbs, can reduce hepatic lipid accumulation and steatosis; however, the exact mechanism remains unclear. This study aimed to investigate the protective mechanisms of diosgenin against NAFLD. We utilized network pharmacology and molecular docking approaches to identify the pathways through which diosgenin improves NAFLD. In high-fat diet (HFD)-fed rats, we measured biochemical markers in the serum and liver. Liver histopathology was assessed using HE and oil-red O staining. In free fatty acids (FFAs)-induced HepG2 cells, we employed the cell transfection overexpression method to verify the regulatory relationship of the identified pathways. The mechanisms in vitro and in vivo were examined using quantitative polymerase chain reaction and Western blot analyses. Bioinformatics analysis indicated that the mTOR-FASN/HIF-1α/RELA/VEGFA pathway may be the target pathway for diosgenin in alleviating NAFLD. Diosgenin inhibited hepatic lipid accumulation and pro-inflammatory cytokines in HFD-fed rats, and reduced intracellular lipid accumulation as well as TG, TC, IL-1β, and TNF-α levels in FFAs-induced HepG2 cells. Mechanistically, diosgenin downregulated the expression of p-mTOR, FASN, HIF-1α, RELA, and VEGFA, which are associated with lipid synthesis and inflammation. Overexpression of mTOR abolished the beneficial effects of diosgenin on lipid reduction and inflammation, as well as its inhibitory effects on the expression of FASN, HIF-1α, RELA, and VEGFA. In conclusion, diosgenin alleviates NAFLD through mTOR-mediated inhibition of lipid accumulation and inflammation.

Hyperechogenicity and histopathological features of focal liver lesions

The identification and accurate diagnosis of focal liver lesions are important in modern medicine, where diagnostic radiology plays an essential role. This review aimed to examine the hyperechogenicity and histopathological features of focal liver lesions. Hyperechogenic liver lesions can be either benign or malignant. Evidence shows that hyperechogenicity is caused by factors such as fat deposition, sinusoidal dilation, peliotic changes, and pseudoglandular patterns. Fat deposition is a common cause of increased echogenicity in hepatocellular carcinoma (HCC). Meanwhile, sinusoidal dilation and peliotic changes are more frequently observed in larger HCC nodules. Pseudoglandular patterns, characterized by the reflection of ultrasound waves at the walls of numerous acini, are associated with hyperechogenicity in well-to-moderately differentiated HCCs. Moreover, this review comprehensively examined the histological features that may cause hyperechogenic internal echoes in not only HCCs but also localized liver lesions (metastases of adenocarcinoma and neuroendocrine neoplasm, intrahepatic cholangiocarcinoma, cavernous hemangioma, focal nodular hyperplasia, and angiomyolipoma). To make an accurate diagnosis and provide appropriate management, it is important to understand the histopathological basis for hyperechogenicity in focal liver lesions. By maximizing the accuracy of imaging studies and enhancing the radiology-pathology correlation, unnecessary biopsies can be avoided, thereby reducing potential complications and mortality. This review can help facilitate the effective management of patients with focal liver lesions, thereby resulting in timely and appropriate treatment decision-making.

Repeated Injection of Xylazine Causes Liver Injury Through the PPAR Signaling Pathway in Rats

With the gradual emergence of xylazine as a street drug, incidents of xylazine poisoning are now occurring worldwide. However, it remains unknown whether long-term exposure to xylazine causes nonalcoholic fatty liver disease (NAFLD). In the present study, the rats were injected with xylazine intraperitoneally for 28 consecutive days, and then serum and liver tissues were collected for analysis. Weight loss was observed in the 40 mg/kg group and elevated levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were observed. Histopathologic examination showed hepatic steatosis, necrosis, and fibrosis. By mRNA sequencing, 192 upregulated genes and 277 downregulated genes were found in the 40 mg/kg group, and the PPAR signaling pathway was ranked first in the KEGG pathway analysis. Four genes in the PPAR signaling pathway, Fabp5, Acox2, and Cpt2, were also verified in the 40 mg/kg group by RT-qPCR analysis and western blot. Our results demonstrated that long-term injection of xylazine causes NAFLD and the PPAR signaling pathway plays a core role in the process of xylazine-associated liver injury.

Lipid Profiles, Telomere Length, and the Risk of Malignant Tumors: A Mendelian Randomization and Mediation Analysis

Background/Objectives: The relationship between lipid profiles, telomere length (TL), and cancer risk remains unclear. Methods: This study employed two-sample Mendelian randomization (MR) with mediation analysis to investigate their causal relationships, examining lipid profiles as exposure, TL as mediator, and nine cancer types as outcomes. We conducted our analysis using two-stage least squares (2SLS) regression integrated with inverse variance weighted (IVW) methods to address potential endogeneity and strengthen our causal inference. Results: we found that unfavorable lipid profiles were causally linked to increased TL (p < 0.05). TL showed positive causal associations with lung and hematologic cancers (OR > 1, p < 0.05). Direct associations were observed between total and low-density lipoprotein (LDL) cholesterol and gastric cancer (OR < 1, p < 0.05), and between remnant cholesterol and colorectal cancer (OR > 1, p < 0.05). Mediation analysis revealed TL as a significant mediator in the pathway from lipid profiles to cancer development (p < 0.05). No horizontal pleiotropy was detected. Conclusions: Our findings suggest that lipid metabolism disorders may influence cancer development through telomere regulation, particularly in lung and hematologic cancers. This emphasizes the importance of lipid management in cancer prevention and treatment, especially for these cancer types.

Zhishi Xiebai Guizhi Decoction modulates hypoxia and lipid toxicity to alleviate pulmonary vascular remodeling of pulmonary hypertension in rats

BACKGROUND

Pulmonary hypertension (PH) is a severe cardio-pulmonary vascular disease, involves complex molecular mechanism especially during the pathological process of pulmonary vascular remodeling, brings a significant challenge to clinical treatment and thus resulting in high mortality rates. Classic Traditional Chinese medicine formula, Zhishi Xiebai Guizhi Decoction (ZXGD), holds therapeutic potential for PH. In present study, we sought to explore therapeutic potential of ZXGD against PH in rats.

METHODS

We employed a combination methods of chemical profiling, echocardiographic, morphologic measurements, molecular biology, rats models and cultured pulmonary artery smooth muscle cells (PASMCs) to achieve this.

RESULTS

Eighteen compounds were precisely identified in ZXGD using UHPLC-QTOF-MS/MS. Our data demonstrated ZXGD could alleviate PH by reducing pulmonary artery pressure and alleviating pulmonary vascular remodeling in rats. Specifically, ZXGD was found to intervene in abnormal expansion of PASMCs, thereby attenuating pulmonary vascular remodeling. ZXGD was also observed to modulate expressions of HIF-1α, ROS, and Nrf2 to alleviate hypoxia and oxidative stress. Additionally, ZXGD significantly regulated disorders in pro-inflammatory cytokines, thus mitigating inflammation. Furthermore, ZXGD decreased levels of decadienyl-L-carnitine and LDL-C, while elevating HDL-C and lipid droplet counts, thereby reducing cholesterol and lipid toxicity and preserving mitochondrial function. Importantly, inhibition of HIF-1α reversed expression of key pathological triggers for pulmonary vascular remodeling. Neohesperidin and naringin in ZXGD extract were identified as the primary contributors to its pharmacological effects against PH.

CONCLUSION

Altogether, our study empirically explored therapeutic potential and pharmacological mechanisms of ZXGD in treating PH, offering a groundwork for the development of novel anti-PH drugs.

Hypoxia-Inducible Factor-1α Modulates the Toll-Like Receptor 4/Nuclear Factor Kappa B Signaling Pathway in Experimental Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a devastating disease observed in premature infants, characterized by intestinal ischemia and inflammation. Hypoxia-inducible factor-1 alpha (HIF-1α), a master regulator of the cellular response to hypoxia and ischemia, plays a critical role in NEC pathogenesis. However, the precise mechanisms by which HIF-1α influences the intestines in NEC remain poorly understood. Herein, we aimed to explore the role of HIF-1α in NEC using a transgenic mouse model. We induced NEC in neonatal mice from postnatal day 5 to 9, and various parameters, including intestinal injury, oxidative stress, inflammatory responses, intestinal epithelial cell (IEC) proliferation, and apoptosis, were assessed. The results confirmed that the absence of intestinal epithelial HIF-1α increased the susceptibility of mice to NEC-induced intestinal injury, as evidenced by increased oxidative stress, inflammatory responses, apoptosis, and inhibition of proliferation. Additionally, we observed an upregulation of the Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway specifically in the intestines of mice lacking HIF-1α in IECs (HIF-1αΔIEC) with NEC. These findings provide crucial insights into the role of HIF-1α in regulating intestinal oxidative stress and inflammation to maintain intestinal homeostasis, highlighting its association with the TLR4-NF-κB signaling pathway. Furthermore, these insights might lead to the identification of novel therapeutic targets for the treatment of NEC.

Molecular Pathway and Immune Profile Analysis of IPMN-Derived Versus PanIN-Derived Pancreatic Ductal Adenocarcinomas

Intraductal papillary mucinous neoplasms (IPMN) are commonly detected pancreatic cysts that may transform into pancreatic ductal adenocarcinoma (PDAC). Predicting which IPMNs will progress to PDAC remains a clinical challenge. Moreover, identifying those clinically evident IPMNs for which a surveillance approach is best is a dire clinical need. Therefore, we aimed to identify molecular signatures that distinguished between PDAC with and without clinical evidence of an IPMN to identify novel molecular pathways related to IPMN-derived PDAC that could help guide biomarker development. Data from the Oncology Research Information Exchange Network (ORIEN) multi-institute sequencing project were utilized to analyze 66 PDAC cases from Moffitt Cancer Center and The Ohio State University Wexner Medical Center, for which tumor whole transcriptome sequencing datasets were generated. Cases were classified based on whether a tumor had originated from an IPMN (n = 16) or presumably through the pancreatic intraepithelial neoplasia (PanIN) pathway (n = 50). We then performed differential expression and pathway analysis using Gene-Set Enrichment Analysis (GSEA) and Pathway Analysis with Down-weighted Genes (PADOG) algorithms. We also analyzed immune profiles using the Tumor-Immune Microenvironment Deconvolution web portal for Bulk Transcriptomics (TIMEx). Both GSEA and TIMEx indicate that PanIN-derived PDAC tumors enrich inflammatory pathways (complement, hedgehog signaling, coagulation, inflammatory response, apical surface, IL-2/STAT5, IL-6/STAT3, EMT, KRAS signaling, apical junction, IFN-gamma, allograft rejection) and are comparatively richer in almost all immune cell types than those from IPMN-derived PDAC. IPMN-derived tumors were enriched for metabolic and energy-generating pathways (oxidative phosphorylation, unfolded protein response, pancreas beta cells, adipogenesis, fatty acid metabolism, protein secretion), and the most significantly upregulated genes (padj < 0.001) included mucin 2 (MUC2) and gastrokine-2 (GKN2). Further, the metabolic-linked gene signature enriched in the IPMN-derived samples is associated with a cluster of early-stage and long-survival (top 4th quartile) PDAC cases from The Cancer Genome Atlas (TCGA) expression database. Our data suggest that IPMN-derived and PanIN-derived PDACs differ in the expression of immune profiles and metabolic pathways. These initial findings warrant validation and follow-up to develop biomarker-based strategies for early PDAC detection and treatment.

Zbtb7b defines a compensatory mechanism in MASLD-related HCC progression by suppressing H19-mediated hepatic lipid deposition

Hepatocellular carcinoma (HCC) is a widely prevalent type of primary liver cancer. However, strategies for pretumor intervention are still limited. In this study, a liver-specific Zbtb7b knockout mouse model was used to evaluate the role of Zbtb7b in metabolic dysfunction-associated steatotic liver disease (MASLD)-related HCC development. We revealed that Zbtb7b was compensatively increased and restricted lipid deposition in the liver during MASLD progression, which protects against MASLD-related HCC initiation. Mechanistically, Zbtb7b suppresses the expression of the long noncoding RNA H19 to attenuate hepatic de novo lipogenesis and increase fatty acid oxidation, thereby preventing lipid accumulation in hepatocytes. As a result, the proliferation and migration abilities of HCC cells are reduced. Overall, we demonstrated that Zbtb7b serves as a tumor suppressor at an early stage of HCC, thus providing a promising target for the treatment of HCC at a premalignant stage.

SARS-CoV-2 NSP16 promotes IL-6 production by regulating the stabilization of HIF-1α

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of coronavirus disease 2019 (COVID-19). Severe and fatal COVID-19 cases often display cytokine storm i.e. significant elevation of pro-inflammatory cytokines and acute respiratory distress syndrome (ARDS) with systemic hypoxia. Understanding the mechanisms of these pathogenic manifestations would be essential for the prevention and especially treatment of COVID-19 patients. Here, using a dual luciferase reporter assay for hypoxia-response element (HRE), we initially identified SARS-CoV-2 nonstructural protein 5 (NSP5), NSP16, and open reading frame 3a (ORF3a) to upregulate hypoxia-inducible factor-1α (HIF-1α) signaling. Further experiments showed NSP16 to have the most prominent effect on HIF-1α, thus contributing to the induction of COVID-19 associated pro-inflammatory response. We demonstrate that NSP16 interrupts von Hippel-Lindau (VHL) protein interaction with HIF-1α, thereby inhibiting ubiquitin-dependent degradation of HIF-1α and allowing it to bind HRE region in the IL-6 promoter region. Taken together, the findings imply that SARS-CoV-2 NSP16 induces HIF-1α expression, which in turn exacerbates the production of IL-6.

Stigmasterol exerts antiglioma effects by regulating lipid metabolism

Stigmasterol is a sterol compound found in various traditional Chinese medicines; however, its effects on glioma remain unclear. The present study aimed to investigate the effects of stigmasterol on the biological behaviors of glioblastoma (GBM) cells and to explore the underlying mechanisms. In vitro experiments assessed its effects on GBM cell proliferation, apoptosis, cell cycle progression, invasion, migration and vasculogenic mimicry (VM). The potential targets for stigmasterol in treating GBM were identified using databases and Venn diagram analysis, followed by enrichment analysis using R language. A prognostic model related to the target genes of stigmasterol was developed through univariate Cox regression and least absolute shrinkage and selection operator analyses. Stigmasterol was found to suppress the proliferation of GBM cells in a dose‑ and time‑dependent manner, to induce apoptosis, and to inhibit invasion, migration and VM formation. Additionally, 31 potential targets of stigmasterol were identified, linked to lipid metabolism and the G protein‑coupled receptor signaling pathway. Lipid metabolism assays revealed that stigmasterol significantly reduced free fatty acids and total cholesterol levels. Furthermore, two prognosis‑related target genes, fatty acid binding protein 5 and α‑1B adrenergic receptor, were selected, and the prognostic model effectively predicted GBM outcomes. Moreover, molecular docking revealed strong binding affinities between stigmasterol and the target proteins. Overall, these findings suggested that stigmasterol may exert anti‑glioma effects, which could be potentially mediated through the regulation of lipid metabolism.

Altered metabolic profiles of dermatomyositis with different myositis-specific autoantibodies associated with clinical phenotype

Introduction

Dermatomyositis (DM) is an idiopathic inflammatory myopathy. Because of clinical heterogeneity, the metabolite profile of DM patients with different myositis-specific autoantibodies (MSAs) remains elusive. This study aimed to explore the metabolomics characteristics of the serum in DM with different MSAs, low or high disease activity, and interstitial lung disease.

Methods

Untargeted metabolomics profiling was performed in the serum of a discovery cohort (n=96) and a validation cohort (n=40), consisting of DM patients with MSAs, low or high disease activity, and/or interstitial lung disease (DM-ILD) compared to age- and gender-matched healthy controls (HCs).

Results

The lipid profile in DM was found to be abnormal, especially dysregulated glycerophospholipid metabolism and fatty acid oxidation, which might affect the pathogenesis of DM by disrupting the balance of Th17 and Treg. We identified potential biomarkers of DM that can distinguish between low or high disease activity and reflect lung involvement. Two metabolite combinations including pro-leu, FA 14:0;O can distinguish high disease activity DM from low disease activity DM and HCs, and five including indole-3-lactic acid, dihydrosphingosine, SM 32:1;O2, NAE 17:1, and cholic acid can distinguish DM-ILD from DM without ILD (DM-nonILD). DM with different MSAs had unique metabolic characteristics, which can distinguish between MDA5+DM, Jo-1+DM, and TIF1-γ+DM, and from the antibody-negative groups. The sphingosine metabolism has been found to play an important role in MDA5+DM, which was associated with the occurrence of ILD.

Discussion

Altered metabolic profiles of dermatomyositis were associated with different myositisspecific autoantibodies, disease activity, and interstitial lung disease, which can help in the early diagnosis, prognosis, or selection of new therapeutic targets for DM.

Investigating the diagnostic and prognostic significance of genes related to fatty acid metabolism in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most prevalent and lethal cancers worldwide, with death rates increasing by approximately 2-3% per year. The high mortality and poor prognosis of HCC are primarily due to inaccurate early diagnosis and lack of monitoring when liver transplantation is not feasible. Fatty acid (FA) metabolism is a critical metabolic pathway that provides energy and signaling factors in cancer, particularly in HCC, and promotes malignancy. Therefore, it is essential to explore specific FA metabolism-related diagnostic and prognostic signatures that can enable the effective early diagnosis and monitoring of HCC.

METHODS

In this study, we used genes associated with FA metabolism pathway and weighted gene co-expression network analysis (WGCNA) to establish a gene co-expression network and identify hub genes related to HCC (disease WGCNA) and FA clusters (cluster WGCNA). A diagnostic model was constructed using data downloaded from the Gene Expression Omnibus database (GSE25097), and a prognostic model was established using The Cancer Genome Atlas cohort, in which Univariate Cox regression analysis, multivariate Cox risk model, and LASSO Cox regression analysis were applied. The immune infiltration of HCC cells was evaluated using CIBERSORT. The function of the key SLC22A1 gene was experimentally verified in vitro and in vivo.

RESULTS

Twelve overlapping genes (CPEB3, ASPDH, DEPDC7, ETFDH, UGT2B7, GYS2, F11, ANXA10, CYP2C8, GLYATL1, C6, and SLC22A1) from disease and cluster WGCNA were identified as key genes and used in the construction of the diagnostic and prognostic models. The RF model had the highest area under the ROC curve (AUC) of 0.994 was identified as the most effective for distinguishing patients with HCC with different features. The top five important genes (C6, UGT2B7, SLC22A1, F11, and CYP2C8) from the RF model were selected as diagnostic genes for further analysis (ROC curves: AUC value = 0.986, 95% confidence interval [95% CI] = 0.967-0.999). Moreover, a risk score formula consisting of four genes (GYS2, F11, ANXA10 and SLC22A1) was established and its independent prognostic ability was further demonstrated (univariate Cox regression analysis: hazard ratio [HR] = 3.664%, 95% CI = 2.033-6.605, P < 0.001; multivariate Cox regression analysis: HR = 2.801%, 95% CI = 1.553-5.049, P < 0.001). Additionally, in vitro and in vivo experiments demonstrated that SLC22A1 inhibits HCC tumor development, suggesting it may be a potential therapeutic target for HCC.

CONCLUSIONS

These findings indicate a considerable value of specific FA metabolism-related genes in the diagnostic and prognostic evaluation of HCC, which provide novel insights into the disease's management, as well as has potential implications for personalized treatment strategies. However, further investigation of the effects of these model genes on HCC is required.

Severe Hyporesponsiveness to Erythropoiesis-Stimulating Agents in Patients on Chronic Hemodialysis-Reconsidering the Relationship with Thrombo-Inflammation and Oxidative Stress

BACKGROUND/OBJECTIVES

Besides a multitude of consequences patients on chronic renal replacement therapy have, anemia is one of the most prominent factors making a significant number of patients dependent on erythropoiesis-stimulating agent (ESA) therapy. The aim of this study was to examine the relationship between the levels of a broad spectrum of thrombo-inflammatory and oxidative stress-related biomarkers and the presence and level of ESA hyporesponsiveness in patients undergoing regular chronic hemodialysis.

METHODS

This cross-sectional study included 96 patients treated with chronic hemodialysis. Levels of several thrombo-inflammatory and oxidative stress-related biomarkers, as well as demographic, clinical, and laboratory analyses, were collected and analyzed based on the calculated value of the ESA-hyporesponsiveness index (EHRI).

RESULTS

In the analyzed sample, 58 patients received ESAs. Of all the investigated parameters, only body mass index (BMI), level of plasminogen activator inhibitor-1, and level of L-type fatty acid binding protein (L-FABP) were observed as significant predictors of EHRI. A significant diagnostic potential for ESA resistance has been observed in BMI and L-FABP between ESA-resistant and ESA-non-resistant groups of patients (p = 0.004, area under the curve 0.763 and p = 0.014, area under the curve 0.712, respectively) with the cut-off values of 25.46 kg/m2 and 5355.24 ng/mL, respectively. Having a BMI of 25.46 kg/m2 or less and an L-FABP level higher than 5355.24 ng/mL were observed as significant predictors of ESA resistance (odds ratio 9.857 and 6.125, respectively).

CONCLUSIONS

EHRI was positively predicted by low BMI and high levels of plasminogen activator inhibitor-1 and L-FABP. High levels of L-FABP and low BMI have been observed as strong predictors of ESA resistance.

MOGAT3-mediated DAG accumulation drives acquired resistance to anti-BRAF/anti-EGFR therapy in BRAFV600E-mutant metastatic colorectal cancer

BRAFV600E-mutant metastatic colorectal cancer (mCRC) is associated with poor prognosis. The combination of anti-BRAF/anti-EGFR (encorafenib/cetuximab) treatment for patients with BRAFV600E-mutant mCRC improves clinical benefits; unfortunately, inevitable acquired resistance limits the treatment outcome, and the mechanism has not been validated. Here, we discovered that monoacylglycerol O-acyltransferase 3-mediated (MOGAT3-mediated) diacylglycerol (DAG) accumulation contributed to acquired resistance to encorafenib/cetuximab by dissecting a BRAFV600E-mutant mCRC patient-derived xenograft (PDX) model exposed to encorafenib/cetuximab administration. Mechanistically, the upregulated MOGAT3 promoted DAG synthesis and reduced fatty acid oxidation-promoting DAG accumulation and activated PKCα/CRAF/MEK/ERK signaling, driving acquired resistance. Resistance-induced hypoxia promoted MOGAT3 transcriptional elevation; simultaneously, MOGAT3-mediated DAG accumulation increased HIF1A expression at the translation level through PKCα/CRAF/eIF4E activation, strengthening the resistance status. Intriguingly, reducing intratumoral DAG with fenofibrate or PF-06471553 restored the antitumor efficacy of encorafenib/cetuximab in resistant BRAFV600E-mutant mCRC, which interrupted PKCα/CRAF/MEK/ERK signaling. These findings reveal the critical role of the metabolite DAG as a modulator of encorafenib/cetuximab efficacy in BRAFV600E-mutant mCRC, suggesting that fenofibrate might prove beneficial for resistant BRAFV600E-mutant mCRC patients.

Chronic hypoxia drives the occurrence of ferroptosis in liver of fat greening (Hexagrammos otakii) by activating HIF-1α and promoting iron production

BACKGROUND

Hypoxia caused by global climate change and human activities has become a growing concern eliciting serious effect and damages to aquatic animals. Hexagrammos otakii is usually a victim of hypoxia which caused by high density aquaculture and high nutrient input. The mechanism underlying ferroptosis regulation after hypoxia-stress in liver of H. otakii, however, remains elusive.

METHODS

For a duration of 15 days, expose the H. otakii to low concentrations of dissolved oxygen (3.4 ± 0.2 mg/L). Detecting alterations in the H. otakii liver tissue by chemical staining, immunohistochemistry, and electron microscopy. The expression variations of relevant genes in the liver of the H. otakii were simultaneously detected using Western blot and qPCR. A correlation analysis was performed between HIF-1α and iron ion expression in the liver of H. otakii following hypoxic stress.

RESULTS

In this study, we conducted the whole ferroptosis integrated analysis of H. otakii under chronic hypoxic condition. Reactive oxygen species (ROS) are highly accumulated under the hypoxia treatment (Superoxide Dismutase, SOD; Catalase, CAT), and which results in a significantly enhanced of lipid peroxidation (Lipid Peroxidation, LPO; Malondialdehyde, MDA; Aminotransferase, AST; Alanine aminotransferase, ALT) in liver tissue. The HIF-1α signaling is activated to cope with the hypoxia stress through strategies including changing iron ion concentration (Fe3+ and TFR1) to breaking the oxidation balance (GSH and GSH-Px), and enhancing ferroptosis gene expression (GPX4). The expression of genes related to ferroptosis pathway (DMT1, FTH1, STEAP3, ACSL4, γ-GCS, SLC7A11) is significantly upregulated and associated to the expression of iron and HIF-1α.

CONCLUSIONS

It is demonstrated that the HIF-1α/Fe3+/ROS/GPX4 axis is involved in promoting ferroptosis in fat greening hepatocytes following hypoxia-stress. Ultimately, our findings unveil a process by which hypoxic stress strongly encourages ferroptosis by triggering HIF-1α and boosting iron synthesis.

Epidemiology, pathophysiology and clinical aspects of Hepatocellular Carcinoma in MAFLD patients

Hepatocellular carcinoma (HCC) is undergoing a transformative shift, with metabolic-associated fatty liver disease (MAFLD) emerging as a dominant etiology. Diagnostic criteria for MAFLD involve hepatic steatosis and metabolic dysregulation. Globally, MAFLD prevalence stands at 38.77%, significantly linked to the escalating rates of obesity. Epidemiological data indicate a dynamic shift in the major etiologies of hepatocellular carcinoma (HCC), transitioning from viral to metabolic liver diseases. Besides the degree of liver fibrosis, several modifiable lifestyle risk factors, such as type 2 diabetes, obesity, alcohol use, smoking, and HBV, HCV infection contribute to the pathogenesis of HCC. Moreover  gut microbiota and genetic variants may contribute to HCC development.The pathophysiological link between MAFLD and HCC involves metabolic dysregulation, impairing glucose and lipid metabolism, inflammation and oxidative stress. Silent presentation poses challenges in early MAFLD-HCC diagnosis. Imaging, biopsy, and AI-assisted techniques aid diagnosis, while HCC surveillance in non-cirrhotic MAFLD patients remains debated.ITA.LI.CA. group proposes a survival-based algorithm for treatment based on Barcelona clinic liver cancer (BCLC) algorithm. Liver resection, transplantation, ablation, and locoregional therapies are applied based on the disease stage. Systemic treatments is promising, with initial immunotherapy results indicating a less favorable response in MAFLD-related HCC.Adopting lifestyle interventions and chemopreventive measures with medications, including aspirin, metformin, and statins, constitute promising approaches for the primary prevention of HCC.Prognosis is influenced by multiple factors, with MAFLD-HCC associated with prolonged survival. Emerging diagnostic biomarkers and epigenomic markers, show promising results for early HCC detection in the MAFLD population.

Glycolysis-Metabolism-Related Prognostic Signature for Ewing Sarcoma Patients

Ewing sarcoma (EwS) is a malignant sarcoma which occurs in bone and soft tissues commonly happening in children with poor survival rates. Changes in cell metabolism, such as glycolysis, may provide the environment for the transformation and progression of tumors. We aimed to build a model to predict prognosis of EwS patients based on glycolysis and metabolism genes. Candidate genes were obtained by differential gene expression analysis based on GSE17679, GSE17674 and ICGC datasets. We performed GO and KEGG pathway enrichment analysis on candidate genes. Univariate Cox and LASSO Cox regression analyses were conducted to construct a model to calculate the Risk Score. GSEA was done between high-risk and low-risk groups. CIBERSORT was applied to analyze the immune landscape. We got 295 candidate glycolysis-metabolism-related genes which were enriched in 620 GO terms and 18 KEGG pathways. 12 Genes were selected by univariate Cox model and 5 of them were determined by LASSO Cox regression analysis to be used in the construction of the Risk Score model. The Risk Score could be considered as an independent prognosis factor. The immune landscape and immune checkpoints' expression significantly differed between high- and low-risk groups. Our research constructed a new glycolysis-metabolism-related genes (FABP5, EMILIN1, GLCE, PHF11 and PALM3) based prognostic signature for EwS patients and assisted in gaining insight into prognosis to improve therapies further.

De novo synthesis of monounsaturated fatty acids modulates exosome-mediated lipid export from human granulosa cells

BACKGROUND

Ovarian somatic cells support the maturation and fertility of oocytes. Metabolic desaturation of fatty acids in these cells has a positive paracrine impact on the maturation of oocytes. We hypothesized that the enzyme stearoyl-CoA desaturase 1 (SCD1) in granulosa cells regulates the lipid cargo of exosomes secreted from these cells by maintaining the balance between saturated and unsaturated lipids. We investigated the effect of SCD1 on exosome lipid content in a cumulus-granulosa cell model under physiologically relevant in vitro conditions.

METHODS

Non-luteinized human COV434 granulosa cells were subjected to treatment with an inhibitor of SCD1 (SCDinhib) alone, in combination with oleic acid, or under control conditions. Subsequently, the exosomes were isolated and characterized via nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. We used liquid chromatography mass spectrometry to investigate the lipidomic profiles. We used quantitative PCR with TaqMan primers to assess the expression of genes involved in lipogenesis and control of cell cycle progression.

RESULTS

A trend toward exosome production was observed with a shift toward smaller exosome sizes in cells treated with SCD1inhib. This trend reached statistical significance when SCDinhib was combined with oleic acid supplementation. SCD1 inhibition led to the accumulation of saturated omega-6 lipids in exosomes. The latter effect was reversed by oleic acid supplementation, which also improved exosome production and suppressed the expression of fatty acid synthase and Cyclin D2.

CONCLUSION

These findings underscore the critical role of de novo fatty acid desaturation in the regulation of the export of specific lipids through exosomes, with potential implications for controlling intercellular communication within the ovary.

The potential roles of HIF-1α in epithelial-mesenchymal transition and ferroptosis in tumor cells

In tumors, the rapid proliferation of cells and the imperfect blood supply system lead to hypoxia, which can regulate the adaptation of tumor cells to the hypoxic environment through hypoxia-inducible factor-1α (HIF-1α) and promote tumor development in multiple ways. Recent studies have found that epithelial-mesenchymal transition (EMT) and ferroptosis play important roles in the progression of tumor cells. The activation of HIF-1α is considered a key factor in inducing EMT in tumor cells. When HIF-1α is activated, it can regulate EMT-related genes, causing tumor cells to gradually lose their epithelial characteristics and acquire more invasive mesenchymal traits. The occurrence of EMT allows tumor cells to better adapt to changes in the surrounding tissue, enhancing their migratory and invasive capabilities, thus promoting tumor progression. At the same time, HIF-1α also plays a crucial regulatory role in ferroptosis in tumor cells. In a hypoxic environment, HIF-1α may affect processes such as iron metabolism and oxidative stress responses, inducing ferroptosis in tumor cells. This article briefly reviews the dual role of HIF-1α in EMT and ferroptosis in tumor cells, helping to gain a deeper understanding of the regulatory pathways of HIF-1α in the development of tumor cells, providing a new perspective for understanding the pathogenesis of tumors. The regulation of HIF-1α may become an important strategy for future tumor therapy.

Unraveling new players in helminth pathology: extracellular vesicles from Fasciola hepatica and Dicrocoelium dendriticum exert different effects on hepatic stellate cells and hepatocytes

Fasciola hepatica and Dicrocoelium dendriticum are parasitic trematodes residing in the bile ducts of mammalian hosts, causing, in some cases, impairment of liver function and hepatic fibrosis. Previous studies have shown that extracellular vesicles released by F. hepatica (FhEVs) and D. dendriticum (DdEVs) induce a distinct phenotype in human macrophages, but there is limited information on the effect of parasitic EVs on liver cells, which interact directly with the worms in natural infections. In this study, we isolated FhEVs and DdEVs by size exclusion chromatography and labeled them with a lipophilic fluorescent dye to analyze their uptake by human hepatic stellate cells (HSC) and hepatocytes, important cell types in liver pathology, using synthetic liposomes as internal labeling and uptake control. We analyzed EV uptake and the proteome profiles after the treatment with EVs for both cell types. Our results reveal that EVs establish unique and specific interactions with stellate cells and hepatocytes, suggesting a different role of EVs derived from each parasite, depending on the migration route to reach their final niche. FhEVs have a cytostatic effect on HSCs, but induce the extracellular matrix secretion and elicit anti-inflammatory responses in hepatocytes. DdEVs have a more potent anti-proliferative effect than FhEVs and trigger a global inflammatory response, increasing the levels of NF-κB and other inflammatory mediators in both cell types. These interactions may have a major influence on the progression of the disease, serving to generate conditions that may favor the establishment of the helminths in the host.

Metabolic ripple effects - deciphering how lipid metabolism in cancer interfaces with the tumor microenvironment

Cancer cells require a constant supply of lipids. Lipids are a diverse class of hydrophobic molecules that are essential for cellular homeostasis, growth and survival, and energy production. How tumors acquire lipids is under intensive investigation, as these mechanisms could provide attractive therapeutic targets for cancer. Cellular lipid metabolism is tightly regulated and responsive to environmental stimuli. Thus, lipid metabolism in cancer is heavily influenced by the tumor microenvironment. In this Review, we outline the mechanisms by which the tumor microenvironment determines the metabolic pathways used by tumors to acquire lipids. We also discuss emerging literature that reveals that lipid availability in the tumor microenvironment influences many metabolic pathways in cancers, including those not traditionally associated with lipid biology. Thus, metabolic changes instigated by the tumor microenvironment have 'ripple' effects throughout the densely interconnected metabolic network of cancer cells. Given the interconnectedness of tumor metabolism, we also discuss new tools and approaches to identify the lipid metabolic requirements of cancer cells in the tumor microenvironment and characterize how these requirements influence other aspects of tumor metabolism.

TRIM65/NF2/YAP1 Signaling Coordinately Orchestrates Metabolic and Immune Advantages in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide. Significantly activated uridine nucleotide and fatty acid metabolism in HCC cells promote malignant proliferation and immune evasion. Herein, it is demonstrated that the tripartite motif 65 (TRIM65) E3 ubiquitin-protein ligase, O-GlcNAcylated via O-GlcNAcylation transferase, is highly expressed in HCC and facilitated metabolic remodeling to promote the accumulation of products related to uracil metabolism and palmitic acid, driving the progression of HCC. Mechanistically, it is showed that TRIM65 mediates ubiquitylation at the K44 residue of neurofibromatosis type 2 (NF2), the key protein upstream of classical Hippo signaling. Accelerated NF2 degradation inhibits yes-associated protein 1 phosphorylation, inducing aberrant activation of related metabolic enzyme transcription, and orchestrating metabolic and immune advantages. In conclusion, these results reveal a critical role for the TRIM family molecule TRIM65 in supporting HCC cell survival and highlight the therapeutic potential of targeting its E3 ligase activity to alter the regulation of proteasomal degradation.

Single-cell RNA sequencing of nc886, a non-coding RNA transcribed by RNA polymerase III, with a primer spike-in strategy

Single-cell RNA sequencing (scRNA-seq) has emerged as a versatile tool in biology, enabling comprehensive genomic-level characterization of individual cells. Currently, most scRNA-seq methods generate barcoded cDNAs by capturing the polyA tails of mRNAs, which exclude many non-coding RNAs (ncRNAs), especially those transcribed by RNA polymerase III (Pol III). Although previously thought to be expressed constitutively, Pol III-transcribed ncRNAs are expressed variably in healthy and disease states and play important roles therein, necessitating their profiling at the single-cell level. In this study, we developed a measurement protocol for nc886 as a model case and initial step for scRNA-seq for Pol III-transcribed ncRNAs. Specifically, we spiked in an oligo-tagged nc886-specific primer during the polyA tail capture process for the 5'scRNA-seq. We then produced sequencing libraries for standard 5' gene expression and oligo-tagged nc886 separately, to accommodate different cDNA sizes and ensure undisturbed transcriptome analysis. We applied this protocol in three cell lines that express high, low, and zero levels of nc886. Our results show that the identification of oligo tags exhibited limited target specificity, and sequencing reads of nc886 enabled the correction of non-specific priming. These findings suggest that gene-specific primers (GSPs) can be employed to capture RNAs lacking a polyA tail, with subsequent sequence verification ensuring accurate gene expression counting. Moreover, we embarked on an analysis of differentially expressed genes in cell line sub-clusters with differential nc886 expression, demonstrating variations in gene expression phenotypes. Collectively, the primer spike-in strategy allows combined analysis of ncRNAs and gene expression phenotype.

LncRNA495810 Promotes Proliferation and Migration of Hepatocellular Carcinoma Cells by Interacting with FABP5

Hepatocellular carcinoma (HCC) is one of the malignant tumors with high morbidity and mortality. Long non-coding RNAs (lncRNAs) are frequently dysregulated in human cancers and play an important role in the initiation and progression of HCC. Here, we investigated the expression of a new reported lncRNA495810 in our previous study by analyzing the publicly available datasets and using RT-qPCR assay. The cell proliferation experiment, cell cycle and apoptosis assay, wound healing assay, cell migration assay were used to explore the biological function of lncRNA495810 in HCC. The western blot, RNA pull down and RNA immunoprecipitation (RIP) detection were used to investigate the potential molecular mechanisms of lncRNA495810. The results demonstrated that lncRNA495810 was significantly upregulated in hepatocellular carcinoma and associated with poor prognosis of hepatocellular carcinoma patients. Moreover, it proved that lncRNA495810 promotes the proliferation and metastasis of hepatoma cells by directly binding and upregulating the expression of fatty acid-binding protein 5. These results reveal the oncogenic roles of lncRNA495810 in HCC and provide a potential therapeutic target for HCC.

High-fat diet consumption promotes adolescent neurobehavioral abnormalities and hippocampal structural alterations via microglial overactivation accompanied by an elevated serum free fatty acid concentration

Mounting evidence suggests that high-fat diet (HFD) consumption increases the risk for depression, but the neurophysiological mechanisms involved remain to be elucidated. Here, we demonstrated that HFD feeding of C57BL/6J mice during the adolescent period (from 4 to 8 weeks of age) resulted in increased depression- and anxiety-like behaviors concurrent with changes in neuronal and myelin structure in the hippocampus. Additionally, we showed that hippocampal microglia in HFD-fed mice assumed a hyperactive state concomitant with increased PSD95-positive and myelin basic protein (MBP)-positive inclusions, implicating microglia in hippocampal structural alterations induced by HFD consumption. Along with increased levels of serum free fatty acids (FFAs), abnormal deposition of lipid droplets and increased levels of HIF-1α protein (a transcription factor that has been reported to facilitate cellular lipid accumulation) within hippocampal microglia were observed in HFD-fed mice. The use of minocycline, a pharmacological suppressor of microglial overactivation, effectively attenuated neurobehavioral abnormalities and hippocampal structural alterations but barely altered lipid droplet accumulation in the hippocampal microglia of HFD-fed mice. Coadministration of triacsin C abolished the increases in lipid droplet formation, phagocytic activity, and ROS levels in primary microglia treated with serum from HFD-fed mice. In conclusion, our studies demonstrate that the adverse influence of early-life HFD consumption on behavior and hippocampal structure is attributed at least in part to microglial overactivation that is accompanied by an elevated serum FFA concentration and microglial aberrations represent a potential preventive and therapeutic target for HFD-related emotional disorders.

A comprehensive analysis of GAS2 family members identifies that GAS2L1 is a novel biomarker and promotes the proliferation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common primary liver cancer with a high incidence and mortality. Members of the growth-arresting-specific 2 (GAS2) family are involved in various biological processes in human malignancies. To date, there is only a limited amount of information available about the expression profile and clinical importance of GAS2 family in HCC. In this study, we found that GAS2L1 and GAS2L3 were distinctly upregulated in HCC specimens compared to non-tumor specimens. Pan-cancer assays indicated that GAS2L1 and GAS2L3 were highly expressed in most cancers. The Pearson's correlation revealed that the expressions of GAS2, GAS2L1 and GAS2L2 were negatively associated with methylation levels. Survival assays indicated that GAS2L1 and GAS2L3 were independent prognostic factors for HCC patients. Immune cell infiltration analysis revealed that GAS2, GAS2L1 and GAS2L3 were associated with several immune cells. Finally, we confirmed that GAS2L1 was highly expressed in HCC cells and its knockdown suppressed the proliferation of HCC cells. Taken together, our findings suggested the expression patterns and prognostic values of GAS2 members in HCC, providing insights for further study of the GAS2 family as sensitive diagnostic and prognostic markers for HCC.

TRIM45 facilitates NASH-progressed HCC by promoting fatty acid synthesis via catalyzing FABP5 ubiquitylation

Non-alcoholic steatohepatitis (NASH) is rapidly surpassing viral hepatitis as the primary cause of hepatocellular carcinoma (HCC). However, understanding of NASH-progressed HCC remains poor, which might impede HCC diagnosis and therapy. In this study, we aim to identify shared transcriptional changes between NASH and HCC, of which we focused on E3 ligase TRIM45. We found TRIM45 exacerbates HCC cells proliferation and metastasis in vitro and in vivo. Further transcriptome analysis revealed TRIM45 predominantly affects fatty acid metabolism and oleic acid restored impaired proliferation and metastasis of TRIM45-deficient HCC cells. IP-tandem mass spectrum and FABP5 depriving experiment indicated that TRIM45 enhance fatty acid synthesis depending on FABP5 presence. Interestingly, we found TRIM45 directly added K33-type and K63-type poly-ubiquitin chains to FABP5 NLS domain, which ultimately promoted FABP5 nuclear translocation. Nuclear FABP5 interacted with PPARγ to facilitate downstream lipid synthesis gene expression. We observed TRIM45 accelerated NASH-to-HCC transition and exacerbated both NASH and NASH-HCC with the enhanced fatty acid production in vivo. Moreover, high concentration of fatty acid increased TRIM45 expression. The established mechanism was substantiated by gene expression correlation in TCGA-LIHC. Collectively, our research revealed a common lipid reprograming process in NASH and HCC and identified the cyclical amplification of the TRIM45-FABP5-PPARγ-fatty acid axis. This signaling pathway offers potential therapeutic targets for therapeutic intervention in NASH and NASH-progressed HCC.

Metabolic heterogeneity in tumor microenvironment - A novel landmark for immunotherapy

The surrounding non-cancer cells and tumor cells that make up the tumor microenvironment (TME) have various metabolic rhythms. TME metabolic heterogeneity is influenced by the intricate network of metabolic control within and between cells. DNA, protein, transport, and microbial levels are important regulators of TME metabolic homeostasis. The effectiveness of immunotherapy is also closely correlated with alterations in TME metabolism. The response of a tumor patient to immunotherapy is influenced by a variety of variables, including intracellular metabolic reprogramming, metabolic interaction between cells, ecological changes within and between tumors, and general dietary preferences. Although immunotherapy and targeted therapy have made great strides, their use in the accurate identification and treatment of tumors still has several limitations. The function of TME metabolic heterogeneity in tumor immunotherapy is summarized in this article. It focuses on how metabolic heterogeneity develops and is regulated as a tumor progresses, the precise molecular mechanisms and potential clinical significance of imbalances in intracellular metabolic homeostasis and intercellular metabolic coupling and interaction, as well as the benefits and drawbacks of targeted metabolism used in conjunction with immunotherapy. This offers insightful knowledge and important implications for individualized tumor patient diagnosis and treatment plans in the future.

Potential molecular mechanisms of Huangqin Tang for liver cancer treatment by network pharmacology and molecular dynamics simulations

OBJECTIVE

This study aims to investigate the mechanism of Huangqin Tang in treating liver cancer.

METHODS

Active ingredients and corresponding targets of Huangqin Tang were obtained from the Traditional Chinese Medicine Systems Pharmacology Database. Differentially expressed genes in liver cancer were identified from mRNA expression data. A protein-protein interaction (PPI) network was constructed using differentially expressed genes and Huangqin Tang targets. Random walk with restart (RWR) analysis was performed on the PPI network. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were conducted. A drug-active ingredient-gene interaction network was established, and molecular docking and molecular dynamics simulations were performed. Finally, the stability of binding between CDK1 and oroxylin was tested according to cellular thermal shift assay (CETSA).

RESULTS

160 active ingredients, 239 targets, and 1093 differentially expressed genes were identified. RWR analysis identified 10 potential targets for liver cancer. Enrichment analysis revealed protein kinase regulator activity and Steroid hormone biosynthesis as significant pathways. Molecular docking suggested a stable complex between oroxylin A and CDK1. CETSA demonstrated that the combination of oroxylin A and CDK1 increased the stability of CDK1, and the combination efficiency was high.

CONCLUSION

Huangqin Tang may treat liver cancer by targeting CDK1 with oroxylin A. Protein kinase regulator activity and Steroid hormone biosynthesis pathways may play a role in liver cancer treatment with Huangqin Tang. This study provides insight into the mechanistic basis of Huangqin Tang for liver cancer treatment.

Zebularine potentiates anti-tumor immunity by inducing tumor immunogenicity and improving antigen processing through cGAS-STING pathway

DNA methylation is an important epigenetic mechanism involved in the anti-tumor immune response, and DNA methyltransferase inhibitors (DNMTi) have achieved impressive therapeutic outcomes in patients with certain cancer types. However, it is unclear how inhibition of DNA methylation bridges the innate and adaptive immune responses to inhibit tumor growth. Here, we report that DNMTi zebularine reconstructs tumor immunogenicity, in turn promote dendritic cell maturation, antigen-presenting cell activity, tumor cell phagocytosis by APCs, and efficient T cell priming. Further in vivo and in vitro analyses reveal that zebularine stimulates cGAS-STING-NF-κB/IFNβ signaling to enhance tumor cell immunogenicity and upregulate antigen processing and presentation machinery (AgPPM), which promotes effective CD4+ and CD8+ T cell-mediated killing of tumor cells. These findings support the use of combination regimens that include DNMTi and immunotherapy for cancer treatment.

Modulation of Epithelial-Mesenchymal Transition Is a Possible Underlying Mechanism for Inducing Chemoresistance in MIA PaCa-2 Cells against Gemcitabine and Paclitaxel

To elucidate the currently unknown molecular mechanisms responsible for the similarity and difference during the acquirement of resistance against gemcitabine (GEM) and paclitaxel (PTX) in patients with pancreatic carcinoma, we examined two-dimensional (2D) and three-dimensional (3D) cultures of parent MIA PaCa-2 cells (MIA PaCa-2-PA) and their GEM resistance cell line (MIA PaCa-2-GR) and PTX resistance (MIA PaCa-2-PR). Using these cells, we examined 3D spheroid configurations and cellular metabolism, including mitochondrial and glycolytic functions, with a Seahorse bio-analyzer and RNA sequencing analysis. Compared to the MIA PaCa-2-PA, (1) the formation of the 3D spheroids of MIA PaCa-2-GR or -PR was much slower, and (2) their mitochondrial and glycolytic functions were greatly modulated in MIA PaCa-2-GR or -PR, and such metabolic changes were also different between their 2D and 3D culture conditions. RNA sequencing and bioinformatic analyses of the differentially expressed genes (DEGs) using an ingenuity pathway analysis (IPA) suggested that various modulatory factors related to epithelial -mesenchymal transition (EMT) including STAT3, GLI1, ZNF367, NKX3-2, ZIC2, IFIT2, HEY1 and FBLX, may be the possible upstream regulators and/or causal network master regulators responsible for the acquirement of drug resistance in MIA PaCa-2-GR and -PR. In addition, among the prominently altered DEGs (Log2 fold changes more than 6 or less than -6), FABP5, IQSEC3, and GASK1B were identified as unique genes associated with their antisense RNA or pseudogenes, and among these, FABP5 and GASK1B are known to function as modulators of cancerous EMT. Therefore, the observations reported herein suggest that modulations of cancerous EMT may be key molecular mechanisms that are responsible for inducing chemoresistance against GEM or PTX in MIA PaCa-2 cells.

SBFI-26 enhances apoptosis in docetaxel-treated triple-negative breast cancer cells by increasing ROS levels

Introduction

Fatty acid binding protein 5 (FABP5) exhibits heightened expression levels in triple-negative breast cancer. The inhibitor of FABP5, Stony Brook fatty acid-binding protein inhibitor 26 (SBFI-26), has demonstrated the capacity to suppress cell proliferation, migration, and invasion. This study delves into the functional mechanism and impact of combining SBFI-26 with docetaxel in treating MDA-MB-231 cells of triple-negative breast cancer.

Methods

Various concentrations of docetaxel and SBFI-26 were chosen for individual or combined treatments. The effects of SBFI-26, docetaxel, or their combination on cell cycle arrest and apoptosis were assessed using flow cytometry. Western blotting was utilised to detect the expression of apoptosis-related proteins, namely cysteinyl aspartate-specific proteases 3 (Caspase3), B cell leukemia/lymphoma 2 (Bcl-2), and Bcl-2 associated X (Bax), while intracellular reactive oxygen species (ROS) levels were determined using a fluorescence spectrophotometer.

Results

The IC50 values for SBFI-26 and docetaxel in inhibiting MDA-MB-231 cells were determined to be 106.1 μM and 86.14 nM, respectively. Significantly, the combination treatment augmented the proportion of G1 phase (apoptotic) cells by 3.67-fold compared to the control group (P < 0.0001). Furthermore, the apoptosis rate in the combination group was 2.59-fold higher than that in the docetaxel group (P < 0.0001) and demonstrated a significant increase of 1.82-fold compared with the SBFI-26 group (P < 0.001). Analyses revealed a decrease in the protein expression of Bcl-2, while Bax and Caspase3 exhibited an increase in the combination group for MDA-MB-231 cells. Moreover, the combined treatment group demonstrated a 2.97-fold increase (P < 0.0001) in ROS fluorescence intensity compared to the control group, a noteworthy 1.39-fold increase (P < 0.01) compared to the SBFI-26 treatment group, and a substantial 1.70-fold increase (P < 0.0001) compared to the docetaxel treatment group.

Conclusion

These findings suggest that the co-administration of SBFI-26 with docetaxel effectively enhances apoptosis in triple-negative breast cancer MDA-MB-231 cells by elevating intracellular ROS levels.