EZH2 Contributes to Anoikis Resistance and Promotes Epithelial Ovarian Cancer Peritoneal Metastasis by Regulating m6A

Anoikis resistance in Cancer: Mechanisms, therapeutic strategies, potential targets, and models for enhanced understanding

Anoikis, defined as programmed cell death triggered by the loss of cell-extracellular matrix (ECM) and cell-cell interactions, is crucial for maintaining tissue homeostasis and preventing aberrant cell migration. Cancer cells, however, display anoikis resistance (AR) which in turn enables cancer metastasis. AR results from alterations in apoptotic signaling, metabolic reprogramming, autophagy modulation, and epigenetic changes, allowing cancer cells to survive in detached conditions. In this review we describe the mechanisms underlying both anoikis and AR, focusing on intrinsic and extrinsic pathways, disrupted cell-ECM interactions, and autophagy in cancer. Recent findings (i.e., between 2014 and 2024) on epigenetic regulation of AR and its role in metastasis are discussed. Therapeutic strategies targeting AR, including chemical inhibitors, are highlighted alongside a network analysis of 122 proteins reported to be associated with AR which identifies 53 hub proteins as potential targets. We also evaluate in vitro and in vivo models for studying AR, emphasizing their role in advancing metastasis research. Our overall goal is to guide future studies and therapeutic developments to counter cancer metastasis.

Metabolic reprogramming and signaling adaptations in anoikis resistance: mechanisms and therapeutic targets

Anoikis, a form of programmed cell death triggered by detachment from the extracellular matrix (ECM), maintains tissue homeostasis by removing mislocalized or detached cells. Cancer cells, however, have evolved multiple mechanisms to evade anoikis under conditions of ECM detachment, enabling survival and distant metastasis. Studies have identified differentially expressed proteins between suspended and adherent cancer cells, revealing that key metabolic and signaling pathways undergo significant alterations during the acquisition of anoikis resistance. This review explores the regulatory roles of epithelial-mesenchymal transition, cancer stem cell characteristics, metabolic reprogramming, and various signaling pathway alterations in promoting anoikis resistance. And the corresponding reagents and non-coding RNAs that target the aforementioned pathways are reviewed. By discussing the regulatory mechanisms that facilitate anoikis resistance in cancer cells, this review aims to shed light on potential strategies for inhibiting tumor progression and preventing metastasis.

Binding of zebrafish lipovitellin and L1‑ORF2 increases the accessibility of L1‑ORF2 via interference with histone wrapping

Long interspersed nuclear element‑1 (L1) is highly expressed in the early embryos of humans, rodents and fish. To investigate the molecular mechanisms underlying high expression of L1 during early embryonic development, a C1‑open reading frame (ORF)2 vector was constructed in which ORF2 of human L1 (L1‑ORF2) was inserted into a pEGFP‑C1 plasmid. C1‑ORF2 vector was injected into early zebrafish embryos (EZEs) to observe expression of EGFP reporter protein by fluorescence microscopy. RNA‑seq and RT‑qPCR were used to detect the effects of lipovitellin (LV)  on gene expression in EZEs. The binding ability of LV to L1‑ORF2 DNA was detected by electrophoretic mobility‑shift assay (EMSA). The chromatin recombinant DNase I digestion and ATAC‑seq assay were used to evaluate the accessibility of plasmid DNA. C1‑ORF2 vector induced high expression of enhanced green fluorescent protein (EGFP) reporter gene after it had been injected into 0 h post‑fertilization (hpf) zebrafish embryos, although histone octamer inhibited expression of EGFP in C1‑ORF2. SDS‑PAGE was used to show that LV was the predominant protein binding ORF2 DNA in 0 hpf zebrafish embryo lysate (ZEL). Both ZEL and purified LV from ZEL attenuated the inhibitory effects induced by histone. LV bound histone to interfere with the binding of histone to ORF2 DNA. Both in vitro chromatin reconstitution experiments and assay for transposase‑accessible chromatin with sequencing with HeLa cells were utilized to demonstrate that the interference induced by LV resulted in increased accessibility of C1‑ORF2. Transcription experiments in vitro verified that LV could enhance the mRNA levels of zebrafish early embryo expression genes grainyhead‑like transcription factor 3 (GRHL3), SRY‑box transcription factor 19a (SOX19A) and nanor (NNR) and also of the EGFP gene. LV was found to increase the expression levels of the zebrafish early embryo expression genes in liver tissue after LV had been injected into the abdominal cavity of adult male zebrafish. Taken together, the findings of the present study demonstrated that LV activates the expression of EGFP induced by ORF2 in EZEs by enhancing the accessibility of ORF2 DNA.

Development and validation of biomarkers related to anoikis in liver cirrhosis based on bioinformatics analysis

BACKGROUND

According to study, anoikis-related genes (ARGs) have been demonstrated to play a significant impact in cirrhosis, a major disease threatening human health worldwide.

AIM

To investigate the relationship between ARGs and cirrhosis development to provide insights into the clinical treatment of cirrhosis.

METHODS

RNA-sequencing data related to cirrhosis were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between cirrhotic and normal tissues were intersected with ARGs to derive differentially expressed ARGs (DEARGs). The DEARGs were filtered using the least absolute shrinkage and selection operator, support vector machine recursive feature elimination, and random forest algorithms to identify biomarkers for cirrhosis. These biomarkers were used to create a nomogram for predicting the prognosis of cirrhosis. The proportions of diverse immune cell subsets in cirrhotic vs normal tissues were compared using the CIBERSORT computational method. In addition, the linkage between immune cells and biomarkers was assessed, and a regulatory network of mRNA, miRNA, and transcription factors was constructed relying on the biomarkers.

RESULTS

The comparison of cirrhotic and normal tissue samples led to the identification of 635 DEGs. Subsequent intersection of the DEGs with ARGs produced a set of 26 DEARGs. Subsequently, three DEARGs, namely, ACTG1, STAT1, and CCR7, were identified as biomarkers using three machine-learning algorithms. The proportions of M1 and M2 macrophages, resting CD4 memory T cells, resting mast cells, and plasma cells significantly differed between cirrhotic and normal tissue samples. The proportions of M1 and M2 macrophages, resting CD4 memory T cells, and resting mast cells were significantly correlated with the expression of the three biomarkers. The mRNA-miRNA-TF network showed that ACTG1, CCR7, and STAT1 were regulated by 28, 42, and 35 miRNAs, respectively. Moreover, AR, MAX, EP300, and FOXA1 were found to regulate four miRNAs related to the biomarkers.

CONCLUSION

This study revealed ACTG1, STAT1, and CCR7 as biomarkers of cirrhosis, providing a reference for developing novel diagnostic and therapeutic strategies for cirrhosis.

Anoikis in cell fate, physiopathology, and therapeutic interventions

The extracellular matrix (ECM) governs a wide spectrum of cellular fate processes, with a particular emphasis on anoikis, an integrin-dependent form of cell death. Currently, anoikis is defined as an intrinsic apoptosis. In contrast to traditional apoptosis and necroptosis, integrin correlates ECM signaling with intracellular signaling cascades, describing the full process of anoikis. However, anoikis is frequently overlooked in physiological and pathological processes as well as traditional in vitro research models. In this review, we summarized the role of anoikis in physiological and pathological processes, spanning embryonic development, organ development, tissue repair, inflammatory responses, cardiovascular diseases, tumor metastasis, and so on. Similarly, in the realm of stem cell research focused on the functional evolution of cells, anoikis offers a potential solution to various challenges, including in vitro cell culture models, stem cell therapy, cell transplantation, and engineering applications, which are largely based on the regulation of cell fate by anoikis. More importantly, the regulatory mechanisms of anoikis based on molecular processes and ECM signaling will provide new strategies for therapeutic interventions (drug therapy and cell-based therapy) in disease. In summary, this review provides a systematic elaboration of anoikis, thus shedding light on its future research.

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

The stromal microenvironment endows pancreatic neuroendocrine tumors with spatially specific invasive and metastatic phenotypes

Cancer-associated fibroblasts (CAFs) play an important role in a variety of cancers. However, the role of tumor stroma in nonfunctional pancreatic neuroendocrine tumors (NF-PanNETs) is often neglected. Profiling the heterogeneity of CAFs can reveal the causes of malignant phenotypes in NF-PanNETs. Here, we found that patients with high stromal proportion had poor prognosis, especially for that with infiltrating stroma (stroma and tumor cells that presented an infiltrative growth pattern and no regular boundary). In addition, myofibroblastic CAFs (myCAFs), characterized by FAP+ and α-SMAhigh, were spatially closer to tumor cells and promoted the EMT and tumor growth. Intriguingly, only tumor cells which were spatially closer to myCAFs underwent EMT. We further elucidated that myCAFs stimulate TGF-β expression in nearby tumor cells. Then, TGF-β promoted the EMT in adjacent tumor cells and promoted the expression of myCAFs marker genes in tumor cells, resulting in distant metastasis. Our results indicate that myCAFs cause spatial heterogeneity of EMT, which accounts for liver metastasis of NF-PanNETs. The findings of this study might provide possible targets for the prevention of liver metastasis.

The Roles of Histone Deacetylases in the Regulation of Ovarian Cancer Metastasis

Ovarian cancer is the most lethal gynecologic malignancy, and metastasis is the major cause of death in patients with ovarian cancer, which is regulated by the coordinated interplay of genetic and epigenetic mechanisms. Histone deacetylases (HDACs) are enzymes that can catalyze the deacetylation of histone and some non-histone proteins and that are involved in the regulation of a variety of biological processes via the regulation of gene transcription and the functions of non-histone proteins such as transcription factors and enzymes. Aberrant expressions of HDACs are common in ovarian cancer. Many studies have found that HDACs are involved in regulating a variety of events associated with ovarian cancer metastasis, including cell migration, invasion, and the epithelial-mesenchymal transformation. Herein, we provide a brief overview of ovarian cancer metastasis and the dysregulated expression of HDACs in ovarian cancer. In addition, we discuss the roles of HDACs in the regulation of ovarian cancer metastasis. Finally, we discuss the development of compounds that target HDACs and highlight their importance in the future of ovarian cancer therapy.