Effects of PPAR-γ agonists on oral cancer cell lines: Potential horizons for chemopreventives and adjunctive therapies

CXCL9 mediating the effect of thyroid disorders on oral and oropharyngeal cancer risk: A mediation Mendelian randomization study

INTRODUCTION

The established association between thyroid disorders (TD) and its two main subtypes-hyperthyroidism and hypothyroidism-and the incidence of oral and oropharyngeal cancer (OCPC) has been substantiated. However, the direct causal relationship and potential intermediary mechanisms linking these conditions have not been clearly defined in prior studies.

MATERIAL & METHODS

This study employed univariate Mendelian randomization (MR) analysis to explore those relationship. Instrumental variables from genome-wide association study (GWAS) datasets for TD (n = 218,792), hyperthyroidism (n = 460,499), hypothyroidism (n = 213,990), and OCPC (n = 12,619), along with 41 intermediary inflammatory cytokines (n = 8293), were analyzed. Inverse variance weighting (IVW) method assessed the causal relationships, while summary MR analysis with pQTL datasets from decode and 91 inflammatory cytokines explored the cytokines' roles as biomarkers and therapeutic targets for OCPC. Multivariable MR (MVMR) analysis quantified the mediation effect of these cytokines in the TD-OCPC relationship.

RESULTS

UVMR analysis provided strong evidence for a causal relationship between TD (OR = 1.376, 95 % CI = 1.142-1.656, p = 0.001), hyperthyroidism (OR = 1.319, 95 % CI=1.129-1.541, p = 0.001), hypothyroidism (OR = 1.224, 95 % CI = 1.071-1.400, p = 0.003), and the risk of OCPC. CXCL9 was identified as a significant intermediary in mediating the risk of OCPC from TD and its two subtypes (OR = 1.218, 95 % CI = 1.016-1.461, P = 0.033), suggesting its potential as a predictive biomarker for OCPC. MVMR analysis further revealed that CXCL9 mediated 7.94 %, 14.4 %, and 18 % of the effects of TD, hyperthyroidism, and hypothyroidism on OCPC risk, respectively.

DISCUSSION

This study not only elucidated the potential causal relationships between TD including its two subtypes and OCPC risk, but also highlighted CXCL9 as a pivotal mediator in this association.

Peroxisome proliferator-activated receptors: A key link between lipid metabolism and cancer progression

Lipids represent the essential components of membranes, serve as fuels for high-energy processes, and play crucial roles in signaling and cellular function. One of the key hallmarks of cancer is the reprogramming of metabolic pathways, especially abnormal lipid metabolism. Alterations in lipid uptake, lipid desaturation, de novo lipogenesis, lipid droplets, and fatty acid oxidation in cancer cells all contribute to cell survival in a changing microenvironment by regulating feedforward oncogenic signals, key oncogenic functions, oxidative and other stresses, immune responses, or intercellular communication. Peroxisome proliferator-activated receptors (PPARs) are transcription factors activated by fatty acids and act as core lipid sensors involved in the regulation of lipid homeostasis and cell fate. In addition to regulating whole-body energy homeostasis in physiological states, PPARs play a key role in lipid metabolism in cancer, which is receiving increasing research attention, especially the fundamental molecular mechanisms and cancer therapies targeting PPARs. In this review, we discuss how cancer cells alter metabolic patterns and regulate lipid metabolism to promote their own survival and progression through PPARs. Finally, we discuss potential therapeutic strategies for targeting PPARs in cancer based on recent studies from the last five years.

PGD2/PTGDR2 Signal Affects the Viability, Invasion, Apoptosis, and Stemness of Gastric Cancer Stem Cells and Prevents the Progression of Gastric Cancer

BACKGROUND

Prostaglandin D2 (PGD2) has been shown to restrict the occurrence and development of multiple cancers; nevertheless, its underlying molecular mechanism has not been fully elucidated. The present study investigated the effect of PGD2 on the biological function of the enriched gastric cancer stem cells (GCSCs), as well as its underlying molecular mechanism, to provide a theoretical basis and potential therapeutic drugs for gastric cancer (GC) treatment.

METHODS

The plasma PGD2 levels were detected by Enzyme-linked immunosorbent assay (ELISA). Silencing of lipocalin prostaglandin D synthetases (L-PTGDS) and prostaglandin D2 receptor 2 (PTGDR2) was carried out in GCSCs from SGC-7901 and HGC-27 cell lines. Cell Counting Kit-8, transwell, flow cytometry, and western blotting assays were used to determine cell viability, invasion, apoptosis, and stemness of GCSCs. In vivo xenograft models were used to assess tumor growth.

RESULTS

Clinically, it was found that the plasma PGD2 level decreased significantly in patients with GC. PGD2 suppressed viability, invasion, and stemness and increased the apoptosis of GCSCs. Downregulating L-PTGDS and PTGDR2 promoted viability, invasion, and stemness and reduced the apoptosis of GCSCs. Moreover, the inhibition of GCSCs induced by PGD2 was eliminated by downregulating the expression of PTGDR2. The results of in vivo experiments were consistent with those of in vitro experiments.

CONCLUSION

Our data suggest that PGD2 may be an important marker and potential therapeutic target in the clinical management of GC. L-PTGDS/PTGDR2 may be one of the critical targets for GC therapy. The PGD2/PTGDR2 signal affects the viability, invasion, apoptosis, and stemness of GCSCs and prevents the progression of GC.

The medicinal perspective of 2,4-thiazolidinediones based ligands as antimicrobial, antitumor and antidiabetic agents: A review

2,4-Thiazolidinedione (2,4-TZD), commonly known as glitazone, is a ubiquitous heterocyclic pharmacophore possessing a plethora of pharmacological activities and offering a vast opportunity for structural modification. The diverse range of biological activities endowed with a novel mode of action, low cost, and easy synthesis has attracted the attention of medicinal chemists. Several researchers have integrated the TZD core with different structural fragments to develop a wide range of lead molecules against various clinical disorders. The most common sites for structural modifications at the 2,4-TZD nucleus are the N-3 and the active methylene at C-5. The review covers the recent development of TZD derivatives such as antimicrobial, anticancer, and antidiabetic agents. Various 2,4-TZD based agents or drugs, which are either under clinical development or in the market, are discussed in the study. Different synthetic methodologies for synthesizing the 2,4-TZD core are also included in the manuscript. The importance of various substitutions at N-3 and C-5 and the mechanisms of action and structure-activity relationships are also discussed. We hope this study will serve as a valuable tool for the scientific community engaged in the structural exploitation of the 2,4-TZD core for developing novel drug m\olecules for life-threatening ailments.

The PPARα and PPARγ Epigenetic Landscape in Cancer and Immune and Metabolic Disorders

Peroxisome proliferator-activated receptors (PPARs) are ligand-modulated nuclear receptors that play pivotal roles in nutrient sensing, metabolism, and lipid-related processes. Correct control of their target genes requires tight regulation of the expression of different PPAR isoforms in each tissue, and the dysregulation of PPAR-dependent transcriptional programs is linked to disorders, such as metabolic and immune diseases or cancer. Several PPAR regulators and PPAR-regulated factors are epigenetic effectors, including non-coding RNAs, epigenetic enzymes, histone modifiers, and DNA methyltransferases. In this review, we examine advances in PPARα and PPARγ-related epigenetic regulation in metabolic disorders, including obesity and diabetes, immune disorders, such as sclerosis and lupus, and a variety of cancers, providing new insights into the possible therapeutic exploitation of PPAR epigenetic modulation.

m6A RNA Methylation Regulators Impact Prognosis and Tumor Microenvironment in Renal Papillary Cell Carcinoma

Accumulating evidence has proven that N6-methyladenosine (m⁶A) RNA methylation plays an essential role in tumorigenesis. However, the significance of m⁶A RNA methylation modulators in the malignant progression of papillary renal cell carcinoma (PRCC) and their impact on prognosis has not been fully analyzed. The present research set out to explore the roles of 17 m⁶A RNA methylation regulators in tumor microenvironment (TME) of PRCC and identify the prognostic values of m⁶A RNA methylation regulators in patients afflicted by PRCC. We investigated the different expression patterns of the m⁶A RNA methylation regulators between PRCC tumor samples and normal tissues, and systematically explored the association of the expression patterns of these genes with TME cell-infiltrating characteristics. Additionally, we used LASSO regression to construct a risk signature based upon the m⁶A RNA methylation modulators. Two-gene prognostic risk model including IGF2BP3 and HNRNPC was constructed and could predict overall survival (OS) of PRCC patients from the Cancer Genome Atlas (TCGA) dataset. The prognostic signature-based risk score was identified as an independent prognostic indicator in Cox regression analysis. Moreover, we predicted the three most significant small molecule drugs that potentially inhibit PRCC. Taken together, our study revealed that m⁶A RNA methylation regulators might play a significant role in the initiation and progression of PRCC. The results might provide novel insight into exploration of m⁶A RNA modification in PRCC and provide essential guidance for therapeutic strategies.

Relevance of Peroxisome Proliferator Activated Receptors in Multitarget Paradigm Associated with the Endocannabinoid System

Cannabinoids have shown to exert their therapeutic actions through a variety of targets. These include not only the canonical cannabinoid receptors CB1R and CB2R but also related orphan G protein-coupled receptors (GPCRs), ligand-gated ion channels, transient receptor potential (TRP) channels, metabolic enzymes, and nuclear receptors. In this review, we aim to summarize reported compounds exhibiting their therapeutic effects upon the modulation of CB1R and/or CB2R and the nuclear peroxisome proliferator-activated receptors (PPARs). Concomitant actions at CBRs and PPARα or PPARγ subtypes have shown to mediate antiobesity, analgesic, antitumoral, or neuroprotective properties of a variety of phytogenic, endogenous, and synthetic cannabinoids. The relevance of this multitargeting mechanism of action has been analyzed in the context of diverse pathologies. Synergistic effects triggered by combinatorial treatment with ligands that modulate the aforementioned targets have also been considered. This literature overview provides structural and pharmacological insights for the further development of dual cannabinoids for specific disorders.