The Role of CD36 in Cancer Progression and Its Value as a Therapeutic Target

A novel 68Ga-labeled cyclic peptide: A potential radiotracer for PET imaging of CD36-positive cancers

PURPOSE

CD36, a transmembrane glycoprotein, which is involved in various cellular functions, including lipid metabolism, inflammation, and tumor initiation and progression, has been considered as an important therapeutic target of tumors. However, the lack of effective imaging methods for non-invasive monitoring of CD36 expression and assessing the efficacy of CD36-targeted therapies limits the clinical application of CD36-targeted therapeutic drugs. To address this issue, we designed and synthesized two novel CD36-targeted radiotracers, and evaluated their biological properties and imaging performance, in order to select the more effective candidate for potential application in monitoring the CD36 expression and assessing the therapeutic efficacy.

METHODS

The chelator NOTA was conjugated to both linear and cyclic peptides via a bioconjugation approach, yielding the linear peptide conjugate ZL01 and the cyclic peptide conjugate ZL02. Their structures were confirmed using HRMS. The solutions of peptide conjugates (ZL01 and ZL02) were mixed with a [68Ga]GaCl₃ solution to obtain the radiotracers, and the radiochemical purity of both radiotracers was determined by radio-HPLC. Non-radioactive [natGa]Ga-ZL01 and [natGa]Ga-ZL02 were used to confirm [68Ga]Ga-ZL01 and [68Ga]Ga-ZL02. The radiochemical and biological properties were evaluated, including in vitro stability, hydrophilicity, binding affinity, pharmacokinetics, micro PET/CT imaging, and biodistribution.

RESULTS

[68Ga]Ga-ZL01 and [68Ga]Ga-ZL02 were obtained with radiochemical purity over 95 %. Both radiotracers demonstrated hydrophilic character, and good stability in PBS and human serum. The blood clearance of [68Ga]Ga-ZL01 and [68Ga]Ga-ZL02 (half-life) was measured at 17.8 min and 21.6 min, respectively. [natGa]Ga-ZL01 and [natGa]Ga-ZL02 exhibited high binding affinities to U87MG cells, with inhibition constant (Ki) of 1.59 ± 0.35 nM for [natGa]Ga-ZL01 and 1.12 ± 0.44 nM for [natGa]Ga-ZL02, respectively. Micro PET/CT imaging and biodistribution study revealed [68Ga]Ga-ZL02 had superior tumor-to-background ratio and prolonged tumor retention, highlighting its potential as a promising candidate for clinical translation.

CONCLUSIONS

In this study, two CD36-targeted radiotracers ([68Ga]Ga-ZL01 and [68Ga]Ga-ZL02) were developed and evaluated. 68Ga-labeled cyclic peptide [68Ga]Ga-ZL02 demonstrated superior tumor-to-background ratio and prolonged tumor retention time, making it a promising radiotracer for monitoring the CD36 expression and assessing the therapeutical efficacy.

The impact of the tumor microenvironment in the dual burden of obesity-cancer link

Obesity induces systemic perturbations of tissue homeostasis, leading to dyslipidemia, insulin resistance and chronic state of inflammation. Evidence from clinical and preclinical studies links excess of adiposity with increased cancer incidence and suggests that chronic inflammation may contribute to increased cancer risk in obese patients. Over the last decades of obesity research, multifaced and complicated effects of abnormal or excessive expansion of Adipose Tissue have been uncovered. In particular, it is widely described how obesity can exacerbate the tumorigenesis for instance by fueling soluble signals and adipokines and by enhancing tissue inflammation and altering the hormonal balance. Less is known about the paracrine effects of the cancer-associated adipocytes on the tumor cells and still poorly explored is the reciprocal communication between cancer cells and the adipose component of the tumor microenvironment (TME). In this review, we will address the mechanisms by which the peritumoral Adipose Tissue can influence the dynamics of tumoral cells. We will discuss how obesity-induced changes in the tumor microenvironment may enhance tumor growth and aggressive characteristics leading to increased invasiveness and metastatic progression of cancer that leads to a worsen cancer survival in obese subjects. We conclude that targeting the peritumoral adipose component of the TME would be a therapeutic option to prevent cancer development.

CD36 as a marker of acute myeloid leukemia prognosis: A systematic review

CD36 is a glycoprotein associated with resistance to chemotherapy and the recurrence of acute myeloid leukemia. This systematic review aims to evaluate the impact of CD36 on the prognosis of acute myeloid leukemia, a complex heterogeneous malignant hematopoietic disease. The Embase, Scopus, Web of Science, Cochrane Library and SciELO databases were searched until September 2023. Only studies that analyzed CD36 expression in humans were included. Of 905 articles identified from the databases, 600 were screened and nine were included. The Newcastle-Ottawa Scale was used to evaluate the methodological quality of the studies. According to this systematic review, CD36 is associated with different prognostic factors in acute myeloid leukemia, including remission and relapse of the disease, overall survival, and chemoresistance.

Human CD36: Gene Regulation, Protein Function, and Its Role in Atherosclerosis Pathogenesis

Human CD36 plays an important role in ligand binding, signalling, cell adhesion, and the regulation of angiogenesis. As a scavenging receptor, it is responsible for clearing long-chain fatty acids (LCFAs) and removing approximately 50% of oxidised low-density lipoprotein (ox-LDL) from plasma. The CD36 gene is alternatively spliced. It has several alternative promoters and first exons. The alternative transcripts are expressed in multiple tissues, and their expression patterns are highly variable. The molecular mechanisms that regulate CD36 gene expression are complex and reflect its multifunctional role in different tissues. CD36 activity has been linked to several metabolic processes, such as inflammation, angiogenesis, phagocytosis, and energy homeostasis. CD36 plays a key role in regulating vascular and cardiovascular health and in the pathogenesis of atherosclerosis. CD36 gene mutations in the Caucasian population are rare. Hence, it is extremely difficult to recruit a statistically significant group of CAD patients with these mutations. Nevertheless, this population is largely at risk of cardiovascular disease. Atherosclerosis is a multifactorial disease, but the role of the CD36 receptor in the development of ox-LDL is extremely important. This review aims to introduce readers to issues related to the relationship between CD36 and CAD. The activity of this receptor should be considered when exploring treatment options for atherosclerosis-related complications.

Lipid metabolism in cancer: Exploring phospholipids as potential biomarkers

Aberrant lipid metabolism is increasingly recognized as a hallmark of cancer, contributing to tumor growth, metastatic dissemination, and resistance to therapy. Cancer cells reprogram key metabolic pathways-including de novo lipogenesis, lipid uptake, and phospholipid remodeling-to sustain malignant progression and adapt to microenvironmental demands. This review summarizes current insights into the role of lipid metabolic reprogramming in oncogenesis and highlights recent advances in lipidomics that have revealed cancer type- and stage-specific lipid signatures with diagnostic and prognostic relevance. We emphasize the dual potential of lipid metabolic pathways-particularly those involving phospholipids-as sources of clinically relevant biomarkers and therapeutic targets. Enzymes and transporters involved in these pathways have emerged as promising candidates for both diagnostic applications and pharmacological intervention. We also examine persistent challenges hindering the clinical translation of lipid-based approaches, including analytical variability, insufficient biological validation, and the lack of standardized integration into clinical workflows. Furthermore, the review explores strategies to overcome these barriers, highlighting the importance of incorporating lipidomics into multi-omics frameworks, supported by advanced computational tools and AI-driven analytics, to decipher the complexity of tumor-associated metabolic networks. We discuss how such integrative approaches can facilitate the identification of actionable metabolic targets, improve the specificity and robustness of lipid-based biomarkers, and enhance patient stratification in the context of precision oncology.

Lipid Metabolism in Gastrointestinal Malignancies: Exploring Dysregulation, Biomarkers, and Treatment Strategies

BACKGROUND

Gastrointestinal malignancies are a major public health concern worldwide, characterized by high incidence and mortality rates. Despite continuous advancements in existing treatment methods, overall survival rates remain low. Lipid metabolism plays a crucial role in the occurrence, progression, and treatment of gastrointestinal malignancies. Its involvement in the metabolic reprogramming of tumor cells, regulation of the tumor microenvironment, and drug response has become a research hotspot.

MATERIALS & METHODS

This review summarizes current research related to lipid metabolism mechanisms, biomarkers, and therapies in GI cancers, with emphasis on its interaction with the tumor microenvironment.

Novel molecular mechanisms of immune evasion in hepatocellular carcinoma: NSUN2-mediated increase of SOAT2 RNA methylation

BACKGROUND

Hepatocellular carcinoma (HCC) is a deadly malignancy known for its ability to evade immune surveillance. NOP2/Sun RNA methyltransferase family member 2 (NSUN2), an RNA methyltransferase involved in carcinogenesis, has been associated with immune evasion and energy metabolism reprogramming. This study aimed to examine the molecular mechanisms underlying the involvement of NSUN2 in immune evasion and metabolic reprogramming of HCC.

METHODS

Single-cell transcriptomic sequencing was applied to examine cellular composition changes, particularly immune cell dynamics, in HCC and adjacent normal tissues. Bulk RNA-seq and proteomics identified key genes and proteins. Methylation sequencing and methylated RNA immunoprecipitation (MeRIP) were carried out to characterize the role of NSUN2 in 5-methylcytosine (m5C) modification of sterol O-acyltransferase 2 (SOAT2). Clinical samples from 30 HCC patients were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blotting. Gene expression was manipulated using CRISPR/Cas9 and lentiviral vectors. In vitro co-culture models and metabolomics were used to study HCC cell-T cell interactions, energy metabolism, and immune evasion. Tumor growth in an orthotopic mouse model was monitored by bioluminescence imaging, with subsequent measurements of tumor weight, volume, and immunohistochemical staining.

RESULTS

Single-cell transcriptomic analysis identified a marked increase in malignant cells in HCC tissues. Cell communication analysis indicated that tumor cells might promote cancer progression by evading immune clearance. Multi-omics analyses identified NSUN2 as a key regulator in HCC development. MeRIP confirmed that NSUN2 facilitated the m5C modification of SOAT2. Analysis of human HCC tissue samples demonstrated pronounced upregulation of NSUN2 and SOAT2, along with elevated m5C levels in HCC tissues. In vitro experiments uncovered that NSUN2 augmented the reprogramming of energy metabolism and repressed the activity and cytotoxicity of CD8+ T cells, contributing to immune evasion. In vivo studies further substantiated the role of NSUN2 in fostering immune evasion and tumor formation of HCC by modulating the m5C modification of SOAT2.

CONCLUSIONS

The findings highlight the critical role of NSUN2 in driving HCC progression through the regulation of m5C modification on SOAT2. These findings present potential molecular markers for HCC diagnosis and therapeutic targets for its treatment.

Wolf in Sheep's Clothing: Taming Cancer's Resistance with Human Serum Albumin?

Human serum albumin (HSA) has emerged as a promising carrier for nanodrug delivery, offering unique structural properties that can be engineered to overcome key challenges in cancer treatment, especially resistance to chemotherapy. This review focuses on the cellular uptake of albumin-based nanoparticles and the modifications that enhance their ability to bypass resistance mechanisms, particularly multidrug resistance type 1 (MDR1), by improving targeting to cancer cells. In our unique approach, we integrate the chemical properties of albumin, its interactions with cancer cells, and surface modifications of albumin-based delivery systems that enable to bypass resistance mechanisms, particularly those related to MDR1, and precisely target receptors on cancer cells to improve treatment efficacy. We discuss that while well-established albumin receptors such as gp60 and gp18/30 are crucial for cellular uptake and transcytosis, their biology remains underexplored, limiting their translational potential. Additionally, we explore the potential of emerging targets, such as cluster of differentiation 44 (CD44), cluster of differentiation (CD36) and transferrin receptor TfR1, as well as the advantages of using dimeric forms of albumin (dHSA) to further enhance delivery to resistant cancer cells. Drawing from clinical examples, including the success of albumin-bound paclitaxel (Abraxane) and new formulations like Pazenir and Fyarro (for Sirolimus), we identify gaps in current knowledge and propose strategies to optimize albumin-based systems. In conclusion, albumin-based nanoparticles, when tailored with appropriate modifications, have the potential to bypass multidrug resistance and improve the targeting of cancer cells. By enhancing albumin's ability to efficiently deliver therapeutic agents, these carriers represent a promising approach to addressing one of oncology's most persistent challenges, with substantial potential to improve cancer treatment outcomes.

Unraveling lipid metabolism for acute myeloid leukemia therapy

PURPOSE OF REVIEW

The aim of this review is to highlight the importance of lipids' intricate and interwoven role in mediating diverse acute myeloid leukemia (AML) processes, as well as potentially novel lipid targeting strategies. This review will focus on new studies of lipid metabolism in human leukemia, particularly highlighting work in leukemic stem cells (LSCs), where lipids were assessed directly as a metabolite.

RECENT FINDINGS

Lipid metabolism is essential to support LSC function and AML survival through diverse mechanisms including supporting energy production, membrane composition, signaling pathways, and ferroptosis. Recent work has highlighted the role of lipid rewiring in metabolic plasticity which can underlie therapy response, the impact of cellular and genetic heterogeneity in AML on lipid metabolism, and the discovery of noncanonical roles of lipid related proteins in AML.

SUMMARY

Recent findings around lipid metabolism clearly demonstrates their importance to our understanding and therapeutic targeting of AML. We have only begun to unravel the regulation and utilization of lipids in this disease. Further, understanding the layered dynamics of lipid homeostasis could provide novel opportunities to target lipid metabolism in AML and LSCs with the potential of improving outcomes for patients with AML.

CD36 inhibition enhances the anti-proliferative effects of PI3K inhibitors in PTEN-loss anti-HER2 resistant breast cancer cells

BACKGROUND

HER2-positive patients comprise approximately 20% of breast cancer cases, with HER2-targeted therapy significantly improving progression-free and overall survival. However, subsequent reprogramed tumor progression due to PI3K signaling pathway activation by PIK3CA mutations and/or PTEN-loss cause anti-HER2 resistance. Previously, alpha isoform-specific PI3K inhibitors were shown to potentiate HER2-targeted therapy in breast cancer cells carrying PI3K pathway alterations with less potent effects on PTEN-loss than PIK3CA-mutant cells. Therefore, seeking for alternative combination therapy needs urgent attentions in PTEN-loss anti-HER2 resistant breast cancer.

METHODS

Since remodeling of fatty acid (FA) metabolism might contribute to HER-positive breast cancer and is triggered by the PI3K signal pathway, herein, we examined the effects of the inhibition of endogenous FA conversion, SCD-1 or exogenous FA transport, CD36, in combination with PI3K inhibitors (alpelisib and inavolisib) in anti-HER2 resistant PTEN-loss breast cancer cells.

RESULTS

The activated HER2/PI3K/AKT/mTOR signaling pathway positively correlated with SCD-1 and CD36 expression in PTEN-loss breast cancer cells. PI3K inhibition downregulated SCD-1, and accordingly, the addition of the SCD-1 inhibitor did not augment the antiproliferative effects of the PI3K inhibitors. CD36 was upregulated by blocking the PI3K signal pathway or limited serum supplementation, indicating that suppressing CD36 may decrease the excess transport of exogenous FA. The addition of the CD36 inhibitor synergistically enhanced the anti-proliferative effects of the PI3K inhibitors.

CONCLUSION

Simultaneously targeting the PI3K signaling pathway and exogenous FA uptake could potentially be advantageous for patients with PTEN-loss anti-HER2 resistant breast cancer.

Discovery and in vitro characterization of a human anti-CD36 scFv

Introduction

CD36 is a membrane receptor that participates in the cellular uptake of fatty acids and lipid metabolism. CD36 overexpression favors progression of different pathologies, such as atherosclerosis and cancer. Thus, CD36 targeting has medicinal relevance. Herein, we aimed to identify human anti-CD36 single-chain variable fragment (scFv) with therapeutic potential.

Methods

The semisynthetic ALTHEA Gold Plus Libraries™ were panned using recombinant human CD36. Clone selection was performed by ELISA. Analysis of scFv binding and blocking function was evaluated by flow cytometry in macrophage-like THP-1 cells and hepatocellular carcinoma HepG2 cells. The phenotypic changes induced by CD36 ligands were assessed in vitro by: i) oil red staining, ii) tumorsphere assays, and iii) RT-qPCR.

Results

We identified an anti-CD36 scFv, called D11, that competes with a commercial anti-CD36 antibody with proven efficacy in disease models. D11 binds to CD36 expressed in the membrane of the cellular models employed and reduces the uptake of CD36 ligands. In macrophage-like THP-1 cells, D11 impaired the acquisition of foam cell phenotype induced by oxLDL, decreasing lipid droplet content and the expression of lipid metabolism genes. Treatment of HepG2 cells with D11 reduced lipid accumulation and the enhanced clonogenicity stimulated by palmitate.

Conclusion

We discovered a new fully human scFv that is an effective blocker of CD36. Since D11 reduces the acquisition of pathogenic features induced by CD36 ligands, it could support the generation of therapeutic proteins targeting CD36.

Dysregulation of genes involved in the long-chain fatty acid transport in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive lethal malignancy with limited options for treatment and a 5-year survival rate of 11% in the United States. As for other types of tumors, such as colorectal cancer, aberrant de novo lipid synthesis and reprogrammed lipid metabolism have been suggested to be associated with PDAC development and progression.

AIM

To identify the possible involvement of lipid metabolism in PDAC by analyzing in tumoral and non-tumoral tissues the expression level of the most relevant genes involved in the long-chain fatty acid (FA) import into cell.

METHODS

A gene expression analysis of FASN, CD36, SLC27A1, SLC27A2, SLC27A3, SLC27A4, SLC27A5, ACSL1, and ACSL3 was performed by qRT-PCR in 24 tumoral PDAC tissues and 11 samples from non-tumoral pancreatic tissues obtained via fine needle aspiration or via surgical resection. The genes were considered significantly dysregulated between the groups when the p value was < 0.05 and the fold change (FC) was ≤ 0.5 and ≥ 2.

RESULTS

We found that three FA transporters and two long-chain acyl-CoA synthetases genes were significantly upregulated in the PDAC tissue compared to the non-tumoral tissue: SLC27A2 (FC = 5.66; P = 0.033), SLC27A3 (FC = 2.68; P = 0.040), SLC27A4 (FC = 3.13; P = 0.033), ACSL1 (FC = 4.10; P < 0.001), and ACSL3 (FC = 2.67; P = 0.012). We further investigated any possible association between the levels of the analyzed mRNAs and the specific characteristics of the tumors, including the anatomic location, the lymph node involvement, and the presence of metastasis. A significant difference in the expression of SLC27A3 (FC = 3.28; P = 0.040) was found comparing patients with and without lymph nodes involvement with an overexpression of this transcript in 17 patients presenting tumoral cells in the lymph nodes.

CONCLUSION

Despite the low number of patients analyzed, these preliminary results seem to be promising. Addressing lipid metabolism through a broad strategy could be a beneficial way to treat this malignancy. Future in vitro and in vivo studies on these genes may offer important insights into the mechanisms linking PDAC with the long-chain FA import pathway.

Suppression of thrombospondin-1-mediated inflammaging prolongs hematopoietic health span

Chronic low-grade inflammation observed in older adults, termed inflammaging, is a common feature underlying a multitude of aging-associated maladies including a decline in hematopoietic activity. However, whether suppression of inflammaging can preserve hematopoietic health span remains unclear, in part because of a lack of tools to measure inflammaging within hematopoietic stem cells (HSCs). Here, we identify thrombospondin-1 (Thbs1) as an essential regulator of inflammaging within HSCs. We describe a transcriptomics-based approach for measuring inflammaging within stem cells and demonstrate that deletion of Thbs1 is sufficient to prevent HSC inflammaging. Our results demonstrate that suppression of HSC inflammaging prevents aging-associated defects in hematopoietic activity including loss of HSC self-renewal, myeloid-biased HSC differentiation, and anemia. Our findings indicate that suppression of HSC inflammaging may also prolong overall systemic health span.

Monocyte-cancer cell fusion is mediated by phosphatidylserine-CD36 receptor interaction and induced by ionizing radiation

Emerging evidence suggests that fusion of cancer cells with leucocytes, such as macrophages, plays a significant role in cancer metastasis and results in tumor hybrid cells that acquire resistance to chemo- and radiation therapy. However, the precise mechanisms behind the leukocyte-cancer cell fusion remain unclear. The present in vitro study explores the presence of fusion between the monocyte cell line (THP-1) and the breast cancer cell line (MCF-7) in relation to the expression of CD36 and phosphatidylserine with and without treatment of these cells with ionizing radiation. The study reveals that spontaneous THP-1/MCF-7 cell fusion increases significantly from 2.8% to 6% after irradiation. The interaction between CD36 and phosphatidylserine plays a pivotal role in THP-1/MCF-7 cell fusion, as inhibiting this interaction using anti-CD36 antibodies significantly reduces cell fusion. While irradiation leads to a dose-dependent escalation in phosphatidylserine expression in MCF-7 cells, it does not impact the expression of CD36 in either THP-1 or MCF-7 cells. To the best of our knowledge, this is the first study to demonstrate the involvement of the CD36-phosphatidylserine interaction in the fusion between monocytes and cancer cells, shedding light on a novel explanatory mechanism for the roles of CD36 and phosphatidylserine in tumor progression.

Theoretical framework and emerging challenges of lipid metabolism in cancer

Elevated lipid metabolism is one of hallmarks of malignant tumors. Lipids not only serve as essential structural components of biological membranes but also provide energy and substrates for the proliferation of cancer cells and tumor growth. Cancer cells meet their lipid needs by coordinating the processes of lipid absorption, synthesis, transport, storage, and catabolism. As research in this area continues to deepen, numerous new discoveries have emerged, making it crucial for scientists to stay informed about the developments of cancer lipid metabolism. In this review, we first discuss relevant concepts and theories or assumptions that help us understand the lipid metabolism and -based cancer therapies. We then systematically summarize the latest advancements in lipid metabolism including new mechanisms, novel targets, and up-to-date pre-clinical and clinical investigations of anti-cancer treatment with lipid metabolism targeted drugs. Finally, we emphasize emerging research directions and therapeutic strategies, and discuss future prospective and emerging challenges. This review aims to provide the latest insights and guidance for research in the field of cancer lipid metabolism.

CD36 as a Therapeutic Target in Tumor Microenvironment and Lipid Metabolism

Dysregulated lipid metabolism within the tumor microenvironment (TME) is a critical hallmark of cancer progression, with lipids serving as a major energy source for tumor cells. Beyond their role in cell membrane synthesis, lipids also provide essential substrates for biomolecule production and activate signaling pathways that regulate various cellular processes. Aberrant lipid metabolism impacts not only function but also alters the behavior of immune and stromal cells within the TME. CD36, a key lipid transporter, plays a crucial role in regulating fatty acid sensing and lipid metabolism, and its dysregulated expression has been associated with poor prognosis in several cancers. Studies have demonstrated that elevated CD 36 expression in the TME is closely linked to abnormal lipid metabolism, promoting tumor growth, migration, and metastasis. In recent years, significant progress has been made in developing CD36-targeted therapies, including small-molecule inhibitors, antibodies, and nanoparticle-based drugs, with many entering experimental or preclinical stages. This review comprehensively summarizes the latest advances in understanding the role of CD36 in the TME, focusing on its metabolic regulatory mechanisms in tumor cells, immune cells, and stromal cells. Additionally, it highlights the contribution of CD36 to immune evasion, drug resistance, and cancer stem cell maintenance while discussing several therapeutic strategies targeting CD36, including novel therapies currently in clinical trials. By exploring the therapeutic potential of CD36, this review provides critical insights for the future development of CD36-targeted cancer therapies.

Assessing CD36 and CD47 expression levels in solid tumor indications to stratify patients for VT1021 treatment

Despite the development of cancer biomarkers and targeted therapies, most cancer patients do not have a specific biomarker directly associated with effective treatment options. We have developed VT1021 that induces the expression of thrombospondin-1 (TSP-1) in myeloid-derived suppressor cells (MDSCs) recruited to the tumor microenvironment (TME). Our studies identified CD36 and CD47 as dual biomarkers that can be used as patient stratifying tools and prognostic biomarkers for VT1021 treatment.

CD36: a promising therapeutic target in hematologic tumors

Cluster of differentiation 36 (CD36) is a multiligand receptor with important roles in lipid metabolism, angiogenesis and innate immunity, and its diverse effects may depend on the binding of specific ligands in different contexts. CD36 is expressed not only on immune cells in the tumor microenvironment (TME) but also on some hematopoietic cells. CD36 is associated with the growth, metastasis and drug resistance in some hematologic tumors, such as leukemia, lymphoma and myelodysplastic syndrome. Currently, some targeted therapeutic agents against CD36 have been developed, such as anti-CD36 antibodies, CD36 antagonists (small molecules) and CD36 expression inhibitors. This paper not only innovatively addresses the role of CD36 in some hematopoietic cells, such as erythrocytes, hematopoietic stem cells and platelets, but also pays special attention to the role of CD36 in the development of hematologic tumors, and suggests that CD36 may be a potential cancer therapeutic target in hematologic tumors.

Roles of posttranslational modifications in lipid metabolism and cancer progression

Lipid metabolism reprogramming has emerged as a hallmark of malignant tumors. Lipids represent a complex group of biomolecules that not only compose the essential components of biological membranes and act as an energy source, but also function as messengers to integrate various signaling pathways. In tumor cells, de novo lipogenesis plays a crucial role in acquiring lipids to meet the demands of rapid growth. Increasing evidence has suggested that dysregulated lipid metabolism serves as a driver of cancer progression. Posttranslational modifications (PTMs), which occurs in most eukaryotic proteins throughout their lifetimes, affect the activity, abundance, function, localization, and interactions of target proteins. PTMs of crucial molecules are potential intervention sites and are emerging as promising strategies for the cancer treatment. However, there is limited information available regarding the PTMs that occur in cancer lipid metabolism and the potential treatment strategies associated with these PTMs. Herein, we summarize current knowledge of the roles and regulatory mechanisms of PTMs in lipid metabolism. Understanding the roles of PTMs in lipid metabolism in cancer could provide valuable insights into tumorigenesis and progression. Moreover, targeting PTMs in cancer lipid metabolism might represent a promising novel therapeutic strategy.

Lipids in the tumor microenvironment: immune modulation and metastasis

Tumor cells can undergo metabolic adaptations that support their growth, invasion, and metastasis, such as reprogramming lipid metabolism to meet their energy demands and to promote survival in harsh microenvironmental conditions, including hypoxia and acidification. Metabolic rewiring, and especially alterations in lipid metabolism, not only fuel tumor progression but also influence immune cell behavior within the tumor microenvironment (TME), leading to immunosuppression and immune evasion. These processes, in turn, may contribute to the metastatic spread of cancer. The diverse metabolic profiles of immune cell subsets, driven by the TME and tumor-derived signals, contribute to the complex immune landscape in tumors, affecting immune cell activation, differentiation, and effector functions. Understanding and targeting metabolic heterogeneity among immune cell subsets will be crucial for developing effective cancer immunotherapies that can overcome immune evasion mechanisms and enhance antitumor immunity.

Chemically synthesized osteocalcin alleviates NAFLD via the AMPK-FOXO1/BCL6-CD36 pathway

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. Osteocalcin plays an important role in energy metabolism. In this study, we investigated the mechanism of action of chemically synthesized osteocalcin (csOCN) in ameliorating NAFLD. We demonstrated for the first time that csOCN attenuates lipid accumulation in the liver and hepatocytes by modulating CD36 protein expression. In addition, we found that the expression of p-AMPK, FOXO1 and BCL6 decreased and the expression of CD36 increased after OA/PA induction compared to the control group, and these effects were reversed by the addition of csOCN. In contrast, the therapeutic effect of csOCN was inhibited by the addition of AMPK inhibitors and BCL6 inhibitors. This finding suggested that csOCN regulates CD36 expression via the AMPK-FOXO1/BCL6 axis. In NAFLD mice, oral administration of csOCN also activated the AMPK pathway and reduced CD36 expression. Molecular docking revealed that osteocalcin has a docking site with CD36. Compared to oleic acid and palmitic acid, osteocalcin bound more strongly to CD36. Laser confocal microscopy results showed that osteocalcin colocalized with CD36 at the cell membrane. In conclusion, we demonstrated the regulatory role of csOCN in fatty acid uptake pathways for the first time; it regulates CD36 expression via the AMPK-FOXO1/BCL6 axis to reduce fatty acid uptake, and it affects fatty acid transport by may directly binding to CD36. There are indications that csOCN has potential as a CD36-targeted drug for the treatment of NAFLD.

CircZNF609 inhibited bladder cancer immunotherapy sensitivity via enhancing fatty acid uptake through IGF2BP2/CD36 pathway

Circular RNAs (circRNAs) are gaining attention for their involvement in immune escape and immunotherapy sensitivity regulation. CircZNF609 is a well-known oncogene in various solid tumours. Our previous research revealed its role in reducing the chemosensitivity of bladder cancer (BCa) to cisplatin. However, the underlying role of circZNF609 in BCa immune escape and immunotherapy sensitivity remains unknown. We conducted BCa cells-CD8 + T cells co-culture assays, cell line-derived xenograft and patient-derived xenograft mouse models with human immune reconstitution to further confirm the role of circZNF609 in BCa immune escape and immunotherapy sensitivity. Overexpression of circZNF609 promoted BCa immune escape in vitro and in vivo. Mechanistically, circZNF609 was bound to IGF2BP2, enhancing its interaction with the 3'-untranslated region of CD36. This increased the stability of the CD36 mRNA, leading to enhanced fatty acid uptake by BCa cells and fatty acid depletion within the tumour microenvironment. Additionally, the nuclear export of circZNF609 was regulated by DDX39B. CircZNF609 promoted immune escape and suppressed BCa immunotherapy sensitivity by regulating the newly identified circZNF609/IGF2BP2/CD36 cascade. Therefore, circZNF609 holds potential as both a biomarker and therapeutic target in BCa immunotherapy.

Emerging targets in lipid metabolism for cancer therapy

Cancer cells perturb lipid metabolic pathways for a variety of pro-tumorigenic functions, and deregulated cellular metabolism is a hallmark of cancer cells. Although alterations in lipid metabolism in cancer cells have been appreciated for over 20 years, there are no FDA-approved cancer treatments that target lipid-related pathways. Recent advances pertaining to cancer cell fatty acid synthesis (FAS), desaturation, and uptake, microenvironmental and dietary lipids, and lipid metabolism of tumor-infiltrating immune cells have illuminated promising clinical applications for targeting lipid metabolism. This review highlights emerging pathways and targets for tumor lipid metabolism that may soon impact clinical treatment.

Transcriptomic analysis of subarachnoid cysts of Taenia solium reveals mechanisms for uncontrolled proliferation and adaptations to the microenvironment

Subarachnoid neurocysticercosis (SANCC) is caused by an abnormally transformed form of the metacestode or larval form of the tapeworm Taenia solium. In contrast to vesicular parenchymal and ventricular located cysts that contain a viable scolex and are anlage of the adult tapeworm, the subarachnoid cyst proliferates to form aberrant membranous cystic masses within the subarachnoid spaces that cause mass effects and acute and chronic arachnoiditis. How subarachnoid cyst proliferates and interacts with the human host is poorly understood, but parasite stem cells (germinative cells) likely participate. RNA-seq analysis of the subarachnoid cyst bladder wall compared to the bladder wall and scolex of the vesicular cyst revealed that the subarachnoid form exhibits activation of signaling pathways that promote proliferation and increased lipid metabolism. These adaptions allow growth in a nutrient-limited cerebral spinal fluid. In addition, we identified therapeutic drug targets that would inhibit growth of the parasite, potentially increase effectiveness of treatment, and shorten its duration.

CD36 as a gatekeeper of myocardial lipid metabolism and therapeutic target for metabolic disease

The multifunctional membrane glycoprotein CD36 is expressed in different types of cells and plays a key regulatory role in cellular lipid metabolism, especially in cardiac muscle. CD36 facilitates the cellular uptake of long-chain fatty acids, mediates lipid signaling, and regulates storage and oxidation of lipids in various tissues with active lipid metabolism. CD36 deficiency leads to marked impairments in peripheral lipid metabolism, which consequently impact on the cellular utilization of multiple different fuels because of the integrated nature of metabolism. The functional presence of CD36 at the plasma membrane is regulated by its reversible subcellular recycling from and to endosomes and is under the control of mechanical, hormonal, and nutritional factors. Aberrations in this dynamic role of CD36 are causally associated with various metabolic diseases, in particular insulin resistance, diabetic cardiomyopathy, and cardiac hypertrophy. Recent research in cardiac muscle has disclosed the endosomal proton pump vacuolar-type H+-ATPase (v-ATPase) as a key enzyme regulating subcellular CD36 recycling and being the site of interaction between various substrates to determine cellular substrate preference. In addition, evidence is accumulating that interventions targeting CD36 directly or modulating its subcellular recycling are effective for the treatment of metabolic diseases. In conclusion, subcellular CD36 localization is the major adaptive regulator of cellular uptake and metabolism of long-chain fatty acids and appears a suitable target for metabolic modulation therapy to mend failing hearts.

The regulatory role of CD36 in hematopoiesis beyond fatty acid uptake

CD36 is a transmembrane glycoprotein, located on surface of numerous cell types. This review is aimed to explore regulatory role of CD36 in hematopoiesis beyond fatty acid uptake. CD36 acts as a pattern recognition receptor, regulates cellular fatty acid homeostasis, and negatively monitors angiogenesis. CD36 also mediates free fatty acid transportation to hematopoietic stem cells in response to infections. During normal physiology and pathophysiology, CD36 significantly participates in the activation and metabolic needs of platelets, macrophages, monocytes, T cells, B cells, and dendritic cells. CD36 has shown a unique relationship with Plasmodium falciparum-infected erythrocytes (PfIEs) as a beneficiary for both parasite and host. CD36 actively participates in pathogenesis of various hematological cancers as a significant prognostic biomarker including AML, HL, and NHL. CD36-targeting antibodies, CD36 antagonists (small molecules), and CD36 expression inhibitors/modulators are used to target CD36, depicting its therapeutic potential. Many preclinical studies or clinical trials were performed to assess CD36 as a therapeutic target; some are still under investigation. This review reflects the role of CD36 in hematopoiesis which requires more consideration in future research.

CD36 as a double-edged sword in cancer

The membrane protein CD36 is a lipid transporter, scavenger receptor, and receptor for the antiangiogenic protein thrombospondin 1 (TSP1). CD36 is expressed by cancer cells and by many associated cells including various cancer-infiltrating immune cell types. Thereby, CD36 plays critical roles in cancer, and it has been reported to affect cancer growth, metastasis, angiogenesis, and drug resistance. However, these roles are partly contradictory, as CD36 has been both reported to promote and inhibit cancer progression. Moreover, the mechanisms are also partly contradictory, because CD36 has been shown to exert opposite cellular effects such as cell division, senescence and cell death. This review provides an overview of the diverse effects of CD36 on tumor progression, aiming to shed light on its diverse pro- and anti-cancer roles, and the implications for therapeutic targeting.

Implication of biosignatures in the progression of endometriosis

Endometriosis is an estrogen-dependent chronic inflammatory disorder involving the placement and growth of endometrial tissue outside the uterine cavity. It is the most common multifactorial disease that affects the life quality of women in reproductive age. Due to its multicomponent nature, early diagnosis of the disease is challenging. Since many genetic, epigenetic alterations and non-genetic factors contribute to the pathology of endometriosis, devising a drug therapy that directly acts on the ectopic tissue is extremely difficult. Endometriosis is a hormone-driven disease with estrogen considered as a primary driver for the development of endometriotic lesions. This study aims to identify biosignatures involved in endometriosis with and without gonadotropin releasing hormone agonists (GnRHa). GnRHa is a short peptide analog of GnRH that causes inhibition of estrogen and androgen synthesis. Microarray based-gene expression profiling was performed on total RNA extracted from endometriotic tissue samples with and without GnRHa-treated patients already published in our previous paper. The untreated group were considered as the control. Genes were then selected for validation by quantitative real-time polymerase chain reaction (qRT-PCR). qRT-PCR analysis confirmed significant downregulation in(p < 0.05) expression of DARC (p = 0.0042), CDH1 (p = 0.0027), CDH5 (p = 0.0283), ATP2A3 (p < 0.001), RGS5 (p = 0.0032), and CD36 (p = 0.0162) in endometriosis patients treated with GnRHa analogs. Although, CTNNAL1 (p = 0.0136) also showed significant results but there was upregulation in their expression levels after GnRHa treatment. Thus, an altered expression of these genes makes them a possible candidate determinant of endometriosis treated with GnRHa.

High-accuracy prediction of colorectal cancer chemotherapy efficacy using machine learning applied to gene expression data

Introduction: FOLFOX and FOLFIRI chemotherapy are considered standard first-line treatment options for colorectal cancer (CRC). However, the criteria for selecting the appropriate treatments have not been thoroughly analyzed. Methods: A newly developed machine learning model was applied on several gene expression data from the public repository GEO database to identify molecular signatures predictive of efficacy of 5-FU based combination chemotherapy (FOLFOX and FOLFIRI) in patients with CRC. The model was trained using 5-fold cross validation and multiple feature selection methods including LASSO and VarSelRF methods. Random Forest and support vector machine classifiers were applied to evaluate the performance of the models. Results and Discussion: For the CRC GEO dataset samples from patients who received either FOLFOX or FOLFIRI, validation and test sets were >90% correctly classified (accuracy), with specificity and sensitivity ranging between 85%-95%. In the datasets used from the GEO database, 28.6% of patients who failed the treatment therapy they received are predicted to benefit from the alternative treatment. Analysis of the gene signature suggests the mechanistic difference between colorectal cancers that respond and those that do not respond to FOLFOX and FOLFIRI. Application of this machine learning approach could lead to improvements in treatment outcomes for patients with CRC and other cancers after additional appropriate clinical validation.

Advances in Targeted Drug Resistance Associated with Dysregulation of Lipid Metabolism in Hepatocellular Carcinoma

Hepatocellular carcinoma is the prevailing malignant neoplasm affecting the liver, often diagnosed at an advanced stage and associated with an unfavorable overall prognosis. Sorafenib and Lenvatinib have emerged as first-line therapeutic drugs for advanced hepatocellular carcinoma, improving the prognosis for these patients. Nevertheless, the issue of tyrosine kinase inhibitor (TKI) resistance poses a substantial obstacle in the management of advanced hepatocellular carcinoma. The pathogenesis and advancement of hepatocellular carcinoma exhibit a close association with metabolic reprogramming, yet the attention given to lipid metabolism dysregulation in hepatocellular carcinoma development remains relatively restricted. This review summarizes the potential significance and research progress of lipid metabolism dysfunction in Sorafenib and Lenvatinib resistance in hepatocellular carcinoma. Targeting hepatocellular carcinoma lipid metabolism holds promising potential as an effective strategy to overcome hepatocellular carcinoma drug resistance in the future.

Glycosylation: A new signaling paradigm for the neurovascular diseases

A wide range of life-threatening conditions with complicated pathogenesis involves neurovascular disorders encompassing Neurovascular unit (NVU) damage. The pathophysiology of NVU is characterized by several features including tissue hypoxia, stimulation of inflammatory and angiogenic processes, and the initiation of intricate molecular interactions, collectively leading to an elevation in blood-brain barrier permeability, atherosclerosis and ultimately, neurovascular diseases. The presence of compelling data about the significant involvement of the glycosylation in the development of diseases has sparked a discussion on whether the abnormal glycosylation may serve as a causal factor for neurovascular disorders, rather than being just recruited as a secondary player in regulating the critical events during the development processes like embryo growth and angiogenesis. An essential tool for both developing new anti-ischemic therapies and understanding the processes of ischemic brain damage is undertaking pre-clinical studies of neurovascular disorders. Together with the post-translational modification of proteins, the modulation of glycosylation and its enzymes implicates itself in several abnormal activities which are known to accelerate neuronal vasculopathy. Despite the failure of the majority of glycosylation-based preclinical and clinical studies over the past years, there is a significant probability to provide neuroprotection utilizing modern and advanced approaches to target abnormal glycosylation activity at embryonic stages as well. This article focuses on a variety of experimental evidence to postulate the interconnection between glycosylation and vascular disorders along with possible treatment options.

Anticancer Activity of Sargassum fluitans Extracts in Different Cancer Cells

BACKGROUND

The arrival of large quantities of Sargassum in the Mexican Caribbean Sea has generated major environmental, health and economic problems. Although Sargassum has been used in the generation of some commercial products, few studies have described its possible applications as a source of compounds with anticancer activity.

OBJECTIVE

This study aimed to evaluate the antiproliferative effects of different Sargassum extracts on various cancer cell lines. Furthermore, LC/QTOF-MS was used to identify the compounds related to the antiproliferative effect.

METHODS

First, determination of the seaweed was performed, and dichloromethane, chloroform and methanol extracts were obtained. The extracts were evaluated for their antiproliferative effects by MTT in breast (MDAMB- 231 and MCF-7), prostate (DU-145), lung (A549) and cervical (SiHa) cancer cell lines. Finally, LC/QTOFMS identified the compounds related to the antiproliferative effect.

RESULTS

The authentication showed Sargassum fluitans as the predominant species. The extracts of dichloromethane and chloroform showed an antiproliferative effect. Interestingly, the fractionation of the chloroform extract showed two fractions (FC1 and FC2) with antiproliferative activity in MDA-MB-231, SiHa and A549 cancer cell lines. On the other hand, three fractions of dichloromethane extract (FD1, FD4 and FD5) also showed antiproliferative effects in the MDA-MB-231, MCF-7, SiHa and DU-145 cancer cell lines. Furthermore, LC/QTOF-MS revealed the presence of eight major compounds in FC2. Three compounds with evidence of anticancer activity were identified (D-linalool-3-glucoside, (3R,4S,6E,10Z)-3,4,7,11-tetramethyl-6,10-tridecadienal and alpha-tocotrienol).

CONCLUSION

These findings showed that Sargassum fluitans extracts are a possible source of therapeutic agents against cancer and could act as scaffolds for new drug discovery.

All-Hydrocarbon Stapled Peptide Multifunctional Agonists at Opioid and Neuropeptide FF Receptors: Highly Potent, Long-Lasting Brain Permeant Analgesics with Diminished Side Effects

Our previous study reported the multifunctional agonist for opioid and neuropeptide FF receptors DN-9, along with its cyclic peptide analogues c[D-Cys2, Cys5]-DN-9 and c[D-Lys2, Asp5]-DN-9. These analogues demonstrated potent antinociceptive effects with reduced opioid-related side effects. To develop more stable and effective analgesics, we designed, synthesized, and evaluated seven hydrocarbon-stapled cyclic peptides based on DN-9. In vitro calcium mobilization assays revealed that most of the stapled peptides, except 3, displayed multifunctional agonistic activities at opioid and neuropeptide FF receptors. Subcutaneous administration of all stapled peptides resulted in effective and long-lasting antinociceptive activities lasting up to 360 min. Among these stapled peptides, 1a and 1b emerged as the optimized compounds, producing potent central antinociception following subcutaneous, intracerebroventricular, and oral administrations. Additionally, subcutaneous administration of 1a and 1b caused nontolerance antinociception, with limited occurrence of constipation and addiction. Furthermore, 1a was selected as the final optimized compound due to its wider safety window compared to 1b.

Robust Identification of Differential Gene Expression Patterns from Multiple Transcriptomics Datasets for Early Diagnosis, Prognosis, and Therapies for Breast Cancer

Background and Objectives: Breast cancer (BC) is one of the major causes of cancer-related death in women globally. Proper identification of BC-causing hub genes (HubGs) for prognosis, diagnosis, and therapies at an earlier stage may reduce such death rates. However, most of the previous studies detected HubGs through non-robust statistical approaches that are sensitive to outlying observations. Therefore, the main objectives of this study were to explore BC-causing potential HubGs from robustness viewpoints, highlighting their early prognostic, diagnostic, and therapeutic performance. Materials and Methods: Integrated robust statistics and bioinformatics methods and databases were used to obtain the required results. Results: We robustly identified 46 common differentially expressed genes (cDEGs) between BC and control samples from three microarrays (GSE26910, GSE42568, and GSE65194) and one scRNA-seq (GSE235168) dataset. Then, we identified eight cDEGs (COL11A1, COL10A1, CD36, ACACB, CD24, PLK1, UBE2C, and PDK4) as the BC-causing HubGs by the protein-protein interaction (PPI) network analysis of cDEGs. The performance of BC and survival probability prediction models with the expressions of HubGs from two independent datasets (GSE45827 and GSE54002) and the TCGA (The Cancer Genome Atlas) database showed that our proposed HubGs might be considered as diagnostic and prognostic biomarkers, where two genes, COL11A1 and CD24, exhibit better performance. The expression analysis of HubGs by Box plots with the TCGA database in different stages of BC progression indicated their early diagnosis and prognosis ability. The HubGs set enrichment analysis with GO (Gene ontology) terms and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways disclosed some BC-causing biological processes, molecular functions, and pathways. Finally, we suggested the top-ranked six drug molecules (Suramin, Rifaximin, Telmisartan, Tukysa Tucatinib, Lynparza Olaparib, and TG.02) for the treatment of BC by molecular docking analysis with the proposed HubGs-mediated receptors. Molecular docking analysis results also showed that these drug molecules may inhibit cancer-related post-translational modification (PTM) sites (Succinylation, phosphorylation, and ubiquitination) of hub proteins. Conclusions: This study's findings might be valuable resources for diagnosis, prognosis, and therapies at an earlier stage of BC.