Comprehensive analysis of the exocytosis pathway genes in cervical cancer

The ester derivative Palmitoylcarnitine abrogates cervical cancer cell survival by enhancing lipotoxicity and mitochondrial dysfunction

BACKGROUND

In cervical cancer (CC), Double C2 Like Domain Beta (DOC2B) functions as a metastatic suppressor. The present study aims to determine whether ectopic expression of DOC2B causes global metabolomic changes in extracellular vesicles (EVs) and corresponds with its tumor suppressive properties.

METHODS

Using a retroviral method, we first ectopically expressed DOC2B in SiHa cells, which do not normally express DOC2B.

RESULTS

We observed that ectopically expressed DOC2B significantly altered the global metabolite profile of EVs. Metabolomics identified significant enrichment of palmitoylcarnitine (PC) in EVs upon ectopic expression of DOC2B. We identified that SiHa and HeLa cells exhibited greater cytotoxicity to PC than gingival fibroblast, HaCaT, Cal27, and MCF7. PC treatment reduced the growth, proliferation, and migration of SiHa and HeLa cells, via increasing apoptosis and decreasing S-Phase cells. PC treatment resulted in morphological alterations, decreased length and number of filopodia, and expression of proteins related to cell cycle progression, proliferation, and the epithelial-to-mesenchymal transition. Further, PC treatment caused mitochondrial morphological changes, increased mitochondrial membrane potential, and decreased mtDNA content. The decreased GSH activity, glucose consumption rate, and lactate production upon PC treatment suggest that PC can induce metabolic reprogramming in CC cells. Increased oxidative stress, calcium overload, lipid droplet accumulation, mitochondrial lipotoxicity, and mitophagy suggest that PC can cause mitochondrial dysfunction. N-acetyl cysteine (NAC) treatment reversed the cytotoxic effect of PC, via decreasing lipid peroxidation rate and increasing GSH activity. PC treatment enhanced the cytotoxic effect of cisplatin in CC.

CONCLUSION

DOC2B restoration or the use of PC may be employed as a novel therapeutic approach for CC.

Biological functions of extracellular vesicle double C2-like domain beta in cervical cancer

Double C-2 Like Domain Beta (DOC2B) located at 17q13.3 prevents metastasis by senescence induction and epithelial to mesenchymal transition inhibition in cervical cancer (CC). The extracellular vesicle (EV) mediated trafficking of DOC2B and its impact on tumor suppressive activity are not investigated in CC. Using a retroviral method, we first ectopically expressed DOC2B in SiHa, which do not normally express DOC2B. DOC2B-SiHa and vector-SiHa EVs were co-incubated separately with recipient cell and subjected to various cellular and biochemical experiments. For the first time, we demonstrated that DOC2B localizes to EVs, and its transfer to EV may require intracellular calcium. Co-culture of SiHa and HeLa cells with DOC2B-SiHa derived EVs induced morphological changes and suppressed their growth and migration, possibly by induction of G0/G1 to S phase arrest and anoikis. DOC2B-SiHa EVs elevated intracellular reactive oxygen species (ROS) and calcium levels and promoted lipid droplet accumulation and lipid peroxidation rate in recipient cells. DOC2B-SiHa EVs reduced active AKT1 and ERK1/2 levels and EMT marker expression and enhanced cellular senescence and cytotoxic effects of cisplatin. Re-expression of DOC2B significantly altered the global metabolite profile of EVs.  Finally, we demonstrated that intracellular calcium chelation significantly reduces DOC2B localization to EVs and impacts its tumor-suppressive properties. Altogether, EV-mediated DOC2B transfer may reduce the aggressive behavior of CC cells.

The Diagnostic and Prognostic Value of Neurotransmitter Receptor-Related Genes in Colon Adenocarcinoma

Colorectal cancer (CRC) is a malignant tumor with high morbidity and mortality in the world. This study aimed to find receptor-related genes (NRGs) with diagnostic and prognostic value in colon adenocarcinoma (COAD). The Cancer Genome Atlas (TCGA) and the Human Protein Atlas database databases were applied to find differential expression NRGs between COAD and normal colonic tissues. Subsequently, Cox regression analysis and minimum absolute contraction and selection operator algorithm were used to construct a prognosis nomogram based on TCGA and Gene Expression Omnibus databases. Expression levels of 35 NRGs were significant differences in COAD and normal colonic tissues. ROC curves showed that 24 NRGs had high diagnostic accuracy (AUC > 0.850) in COAD. Risk score was constructed based on 10 NRGs for the first time. Cox regression analysis revealed risk score was an independent risk factor and a higher risk score predicts a later TNM stage. Finally, a prognostic nomogram containing risk score and clinical features was established. Calibration curves and C-index suggested the powerful predictable value of the model. This study identified the NRGs with diagnostic value and prognostic value, providing a direction for treatment of COAD patients.

Analysis of miR-497/195 cluster identifies new therapeutic targets in cervical cancer

OBJECTIVE

miR-497/195, located at 17p13.1, is a highly conserved miRNA cluster whose abnormal expression is a key regulator of carcinogenesis. We performed a comprehensive analysis of the miR-497/195 cluster to determine its prognostic utility and role in cervical cancer (CC) using publicly available datasets.

RESULTS

In silico analysis and validation revealed that this cluster is downregulated in CC. A total of 60 target genes of miR-497/195 cluster were identified as differentially expressed between normal and CC samples. ShinyGO, STRING, CytoHubba, Timer 2.0, HPA, and HCMBD were used for functional enrichment, PPIN network construction, hub gene identification, immune infiltration correlation, histopathological expression, and determination of the metastatic potential of miR-497/195 cluster and their target genes. PPIN analysis identified CCNE1, CCNE2, ANLN, RACGAP1, KIF23, CHEK1, CDC25A, E2F7, CDK1, and CEP55 as the top 10 hub genes (HGs). Furthermore, the upregulation of RECK, ATD5, and BCL2, downregulation of OSBPL3, RCAN3, and HIST1H3H effected overall survival of CC patients. We identified 6 targets (TFAP2A, CLSPN, RASEF, HIST1H3H, AKT3, and ITPR1) of miR-497/195 cluster to influence metastasis. In addition, 8 druggable genes and 38 potential drugs were also identified. Our study identified miR-497/195 cluster target genes and pathways that could be used for prognostic and therapeutic applications in CC.

Role of ESCCAL-1 in regulating exocytosis of AuNPs in human esophageal squamous carcinoma cells

Exocytosis is a critical factor for designing efficient nanocarriers and determining cytotoxicity. However, the research on the exocytosis mechanism of nanoparticles, especially the role of long non-coding RNAs (lncRNAs), has not been reported. In this study, the exocytosis of AuNPs in the KYSE70 cells and the involved molecular pathways of exocytosis are analyzed. It demonstrates that nanoparticles underwent time-dependent release from the cells by exocytosis, and the release of β-hexosaminidase confirms that AuNPs are excreted through lysosomes. Mechanistic studies reveal that lncRNA ESCCAL-1 plays a vital role in controlling the exocytosis of AuNPs through activation of the MAPK pathway, including the phosphorylation of ERK and JNK. The study implies that the ESCCAL-1-mediated pathway plays an important role in the exocytosis of AuNPs in KYSE70 cells. This finding has implications for the role of ESCCAL-1 on the drug resistance of esophagus cancer by controlling lysosome-mediated exocytosis.

Flipping the script: Advances in understanding how and why P4-ATPases flip lipid across membranes

Type IV P-type ATPases (P4-ATPases) are a family of transmembrane enzymes that translocate lipid substrates from the outer to the inner leaflet of biological membranes and thus create an asymmetrical distribution of lipids within membranes. On the cellular level, this asymmetry is essential for maintaining the integrity and functionality of biological membranes, creating platforms for signaling events and facilitating vesicular trafficking. On the organismal level, this asymmetry has been shown to be important in maintaining blood homeostasis, liver metabolism, neural development, and the immune response. Indeed, dysregulation of P4-ATPases has been linked to several diseases; including anemia, cholestasis, neurological disease, and several cancers. This review will discuss the evolutionary transition of P4-ATPases from cation pumps to lipid flippases, the new lipid substrates that have been discovered, the significant advances that have been achieved in recent years regarding the structural mechanisms underlying the recognition and flipping of specific lipids across biological membranes, and the consequences of P4-ATPase dysfunction on cellular and physiological functions. Additionally, we emphasize the requirement for additional research to comprehensively understand the involvement of flippases in cellular physiology and disease and to explore their potential as targets for therapeutics in treating a variety of illnesses. The discussion in this review will primarily focus on the budding yeast, C. elegans, and mammalian P4-ATPases.

Type IV P-Type ATPases: Recent Updates in Cancer Development, Progression, and Treatment

Adaptations of cancer cells for survival are remarkable. One of the most significant properties of cancer cells to prevent the immune system response and resist chemotherapy is the altered lipid metabolism and resulting irregular cell membrane composition. The phospholipid distribution in the plasma membrane of normal animal cells is distinctly asymmetric. Lipid flippases are a family of enzymes regulating membrane asymmetry, and the main class of flippases are type IV P-type ATPases (P4-ATPases). Alteration in the function of flippases results in changes to membrane organization. For some lipids, such as phosphatidylserine, the changes are so drastic that they are considered cancer biomarkers. This review will analyze and discuss recent publications highlighting the role that P4-ATPases play in the development and progression of various cancer types, as well as prospects of targeting P4-ATPases for anti-cancer treatment.

Systematic Analysis of the Therapy Resistance Genes and their Prognostic Relevance in Cervical Cancer

INTRODUCTION

Critical issues in the therapeutic management of cervical cancer (CC) include therapy resistance and treatment failure. The development of therapy resistance is a multifaceted, progressive process, including genetic and epigenetic abnormalities. The present study aimed to identify genes that may contribute to therapy resistance in CC.

MATERIALS AND METHODS

We have created an extensive list of the genes in cancer that are therapy-resistant using a text-mining approach. The list was compared with the TCGA-CESC dataset to identify the differentially expressed therapy resistance genes (DETRGs) in CC. We used online resources (UALCAN, DNMIVD, cBio- Portal, HCMDB, OncoDB, ShinyGO, HPA, KM Plotter, TIMER, and DGIdb) to determine the potential association between methylation and expression of therapy resistance genes with the prognosis and clinical outcomes in CC.

RESULTS

The systematic analysis identified 71 out of 91 DETRGs showed aberrant DNA methylation. The overlapping analysis identified 25 genes to show an inverse correlation between methylation and expression. Further, differential expression or methylation could be helpful in CC staging, HPV association, prediction of metastasis and prognosis. The study identified seven driver genes in CC. The PPIN identifies ten hub genes (HGs) associated with CC staging, cancer hallmarks, and prognosis to affect long-term survival.

CONCLUSION

Our thorough investigation uncovered several novel genes and pathways that might contribute to therapy resistance in CC. The genes identified in our study may serve as a biomarker, prognostic indicator, and therapeutic target in CC.

Integrated bioinformatic analysis to understand the association between phthalate exposure and breast cancer progression

Phthalates have been extensively used as plasticizers while manufacturing plastic-based consumer products. Estradiol mimicking properties and association studies suggest phthalates may contribute to breast cancer (BC). We performed an in-silico analysis and functional studies to understand the association between phthalate exposure and BC progression. Search for phthalate-responsive genes using the comparative toxicogenomics database identified 20 genes as commonly altered in response to multiple phthalates exposure. Of the 20 genes, 12 were significantly differentially expressed between normal and BC samples. In BC samples, 9 out of 20 genes showed a negative correlation between promoter methylation and its expression. AHR, BAX, BCL2, CAT, ESR2, IL6, and PTGS2 expression differed significantly between metastatic and non-metastatic BC samples. Gene set enrichment analysis identified metabolism, ATP-binding cassette transporters, insulin signaling, and type II diabetes as highly enriched pathways. The diagnostic assessment based on 20 genes expression suggested a sensitivity and a specificity >0.91. The aberrantly expressed phthalate interactive gene influenced the overall survival of BC patients. Drug-gene interaction analysis identified 14 genes and 523 candidate drugs, including 19 BC treatment-approved drugs. Di(2-ethylhexyl) phthlate (DEHP) exposure increased the growth, proliferation, and migration of MCF-7 and MDA-MB-231 cells in-vitro. DEHP exposure induced morphological changes, actin cytoskeletal remodeling, increased ROS content, reduced basal level lipid peroxidation, and induced epithelial to mesenchymal transition (EMT). The present approach can help to explore the potentially damaging effects of environmental agents on cancer risk and understand the underlined pathways and molecular mechanisms.