RNA Demethylase ALKBH5 Prevents Lung Cancer Progression by Regulating EMT and Stemness via Regulating p53

Targeting cell signaling pathway ALKBH5/Beclin1/ULK1 in lung cancer by 5-flurouracil- loaded P (AAm/SA) nanogel in rats

PURPOSE

Lung cancer is the second most common Cancer in the United States; however, it remains the leading cause of cancer-related death in the United States and worldwide. 5-fluorouracil (5-FU) is among the most administrated chemotherapeutic agents for various neoplasms. This study focused on synthesizing and characterizing P(AAm/SA)/5-Fu nanogels as a potential drug delivery system.

METHODS

The nanogels were prepared by combining sodium alginate (SA) and acrylamide (AAm) monomers, followed by gamma irradiation-induced polymerization at a dose of 5 kGy. Then, the obtained nanogel was loaded with 500 ppm of 5-Fu. Transmission electron microscopy (TEM) imaging was utilized to characterize the nanogels' morphology and monodispersity with a particle size of (50 nm). Rats were randomly assigned to four groups (six animals per group): Group 1: (Control): normal healthy. Group 2: Cancer-bearing animals (animals injected with diethylnitrosamine (DEN) 20 mg/kg body weight for 3 months. Group 3: Cancer+ 5-fluorouracil (12 mg/kg body weight). Group4: Cancer+ 5-Flurouracil- Loaded P (AAm/SA) Nanogel.

RESULTS

DEN markedly increased PTGS2, Cox2, PKB, PFKm, and ERK1 levels. Also, observed up-regulation in ALKBH5, Beclin1, ULK1, and P53 gene expressions in the cancer-bearing animal group compared with the control group. 5-fluorouracil nano gel significantly ameliorated the above-mentioned parameters and immunohistochemistry study. 5-fluorouracil nanogel significantly ameliorated the parameters mentioned above, as well as the immunohistochemistry study.

CONCLUSION

The 5-FU-loaded P(AAm/SA) nanogel could serve as a promising approach for targeting tumor cell proliferation, speeding up autophagic processes, and overcoming chemotherapy resistance in lung carcinoma.

Follicle-stimulating hormone promotes EndMT in endothelial cells by upregulating ALKBH5 expression

BACKGROUND

The incidence of atherosclerosis markedly rises following menopause. Our previous findings demonstrated that elevated follicle-stimulating hormone (FSH) levels in postmenopausal women accelerate atherosclerosis progression. Plaque instability, the fundamental pathological factor in acute coronary syndrome, primarily results from vascular embolism due to plaque rupture. Recent evidence highlights that endothelial-to-mesenchymal transition (EndMT) exacerbates plaque instability, although the link between FSH and EndMT has not been fully established. This investigation sought to explore the possible influence of FSH in modulating EndMT.

METHODS

In this study, apolipoprotein E-deficient (ApoE-/-) mice served as an atherosclerosis model, while human umbilical vascular endothelial cells (HUVECs) were used as cellular models. Protein levels were assessed through immunochemical techniques, gene expression was quantified via RT-qPCR, and nucleic acid-protein interactions were evaluated using immunoprecipitation. The m6A modification status was determined by MeRIP, and cellular behaviors were analyzed through standard biochemical assays.

RESULTS

Our results indicate that FSH induces EndMT both in vitro and in vivo. Additional investigation suggested that FSH upregulates the transcription factor Forkhead box protein M1 (FOXM1) at both protein and mRNA levels by enhancing the expression of AlkB homolog 5, RNA demethylase (ALKBH5). FSH reduces m6A modifications on FOXM1 through ALKBH5, leading to increased nascent transcript levels and mRNA stability of FOXM1. Dual-luciferase reporter assays highlighted cAMP-response element binding protein (CREB)'s essential function in facilitating the FSH-induced upregulation of ALKBH5.

CONCLUSIONS

These findings suggest that FSH promotes ALKBH5 expression, facilitates N6-methyladenosine (m6A) demethylation on FOXM1, and consequently, induces EndMT. This study elucidates the impact of FSH on plaque instability and provides insights into potential strategies to prevent acute coronary syndrome in postmenopausal women.

The therapeutic potential of RNA m(6)A in lung cancer

Lung cancer (LC) is a highly malignant and metastatic form of cancer. The global incidence of and mortality from LC is steadily increasing; the mean 5-year overall survival (OS) rate for LC is less than 20%. This frustrating situation may be attributed to the fact that the pathogenesis of LC remains poorly understood and there is still no cure for mid to advanced LC. Methylation at the N6-position of adenosine (N6mA) of RNA (m(6)A) is widely present in human tissues and organs, and has been found to be necessary for cell development and maintenance of homeostasis. However, numerous basic and clinical studies have demonstrated that RNA m(6)A is deregulated in many human malignancies including LC. This can drive LC malignant characteristics such as proliferation, stemness, invasion, epithelial-mesenchymal transition (EMT), metastasis, and therapeutic resistance. Intriguingly, an increasing number of studies have also shown that eliminating RNA m(6)A dysfunction can exert significant anti-cancer effects on LC such as suppression of cell proliferation and viability, induction of cell death, and reversal of treatment insensitivity. The current review comprehensively discusses the therapeutic potential of RNA m(6)A and its underlying molecular mechanisms in LC, providing useful information for the development of novel LC treatment strategies.

Decoding the molecular symphony: interactions between the m6A and p53 signaling pathways in cancer

The p53 tumor suppressor gene governs a multitude of complex cellular processes that are essential for anti-cancer function and whose dysregulation leads to aberrant gene transcription, activation of oncogenic signaling and cancer development. Although mutations can occur at any point in the genetic sequence, missense mutations comprise the majority of observed p53 mutations in cancers regardless of whether the mutation is germline or somatic. One biological process involved in both mutant and wild-type p53 signaling is the N 6-methyladenosine (m6A) epitranscriptomic network, a type of post-transcriptional modification involved in over half of all eukaryotic mRNAs. Recently, a significant number of findings have demonstrated unique interactions between p53 and the m6A epitranscriptomic network in a variety of cancer types, shedding light on a previously uncharacterized connection that causes significant dysregulation. Cross-talk between wild-type or mutant p53 and the m6A readers, writers and erasers has been shown to impact cellular function and induce cancer formation by influencing various cancer hallmarks. Here, this review aims to summarize the complex interplay between the m6A epitranscriptome and p53 signaling pathway, highlighting its effects on tumorigenesis and other hallmarks of cancer, as well as identifying its therapeutic implications for the future.

Role of N6-methyladenosine in tumor neovascularization

Tumor neovascularization is essential for the growth, invasion, and metastasis of tumors. Recent studies have highlighted the significant role of N6-methyladenosine (m6A) modification in regulating these processes. This review explores the mechanisms by which m6A influences tumor neovascularization, focusing on its impact on angiogenesis and vasculogenic mimicry (VM). We discuss the roles of m6A writers, erasers, and readers in modulating the stability and translation of angiogenic factors like vascular endothelial growth factor (VEGF), and their involvement in key signaling pathways such as PI3K/AKT, MAPK, and Hippo. Additionally, we outline the role of m6A in vascular-immune crosstalk. Finally, we discuss the current development of m6A inhibitors and their potential applications, along with the contribution of m6A to anti-angiogenic therapy resistance. Highlighting the therapeutic potential of targeting m6A regulators, this review provides novel insights into anti-angiogenic strategies and underscores the need for further research to fully exploit m6A modulation in cancer treatment. By understanding the intricate role of m6A in tumor neovascularization, we can develop more effective therapeutic approaches to inhibit tumor growth and overcome treatment resistance. Targeting m6A offers a novel approach to interfere with the tumor's ability to manipulate its microenvironment, enhancing the efficacy of existing treatments and providing new avenues for combating cancer progression.

High expression of AlkB homolog 5 suppresses the progression of non-small cell lung cancer by facilitating ferroptosis through m6A demethylation of SLC7A11

OBJECTIVE

Non-small cell lung cancer (NSCLC) is a prevailing LC characterized by poor outcomes. AlkB homolog 5 (ALKBH5) functions as a tumor suppressor in several cancers. This study delved into the role of ALKBH5 in NSCLC development.

METHODS

TCGA database predicted ALKBH5 expression in NSCLC patients. ALKBH5 levels in NSCLC and human bronchial epithelial cells were determined. pcDNA3.1-ALKBH5/NC, pcDNA3.1-SLC7A11/NC, and ferrostatin-1 were used to explore the interactions among ALKBH5, SLC7A11, and ferroptosis. SLC7A11 mRNA and its protein levels were measured by RT-qPCR and Western blot. Cell viability, apoptosis, migration, and invasion were assessed by CCK-8, flow cytometry, and Transwell. Total N6-methyladenosine (m6A) quantification and its enrichment on SLC7A11 mRNA were determined, followed by the observation of Ki67, ALKBH5 and SLC7A11-positive cell numbers. Glutathione (GSH), lipid reactive oxygen species (lipid-ROS), malondialdehyde (MDA), and iron ion contents were determined. Animal experiments further analyzed the role of ALKBH5 in tumor development and glutathione peroxidase 4 (GPX4) expression.

RESULTS

Bioinformatics analysis revealed the lowly-expressed ALKBH5 in LC patients. ALKBH5 was downregulated in NSCLC cells and its upregulation repressed proliferation activity, invasion, and migration, and facilitated apoptosis. ALKBH5 upregulation decreased GSH, increased lipid-ROS, MDA, and iron ion contents, and downregulated SLC7A11 by reducing m6A modification. SLC7A11 upregulation partly annulled the effect of ALKBH5 overexpression on cell ferroptosis and malignant behaviors. In vivo assays elucidated the suppression of ALKBH5 upregulation on tumor development and GPX4 levels.

CONCLUSION

ALKBH5 upregulation downregulates SLC7A11 transcription by decreasing m6A modification, thus promoting NSCLC cell ferroptosis and ultimately repressing NSCLC progression.

LncRNA CARMN m6A demethylation by ALKBH5 inhibits mutant p53-driven tumour progression through miR-5683/FGF2

N-methyladenosine (m6A) represents a prevalent RNA modification observed in colorectal cancer. Despite its abundance, the biological implications of m6A methylation on the lncRNA CARMN remain elusive in colorectal cancer, especially for mutant p53 gain-of-function. Here, we elucidate that CARMN exhibits diminished expression levels in colorectal cancer patients with mutant p53, attributed to its rich m6A methylation, which promotes cancer proliferation, invasion and metastasis in vitro and in vivo. Further investigation illustrates that ALKBH5 acts as a direct demethylase of CARMN, targeting 477 methylation sites, thereby preserving CARMN expression. However, the interaction of mutant p53 with the ALKBH5 promoter impedes its transcription, enhancing m6A methylation levels on CARMN. Subsequently, YTHDF2/YTHDF3 recognise and degrade m6A-modified CARMN. Concurrently, overexpressing CARMN significantly suppressed colorectal cancer progression in vitro and in vivo. Additionally, miR-5683 was identified as a direct downstream target of lncRNA CARMN, exerting an antitumour effect by cooperatively downregulating FGF2 expression. Our findings revealed the regulator and functional mechanism of CARMN in colorectal cancer with mutant p53, potentially offering insights into demethylation-based strategies for cancer diagnosis and therapy. The m6A methylation of CARMN that is prime for mutant p53 gain-of-function-induced malignant progression of colorectal cancer, identifying a promising approach for cancer therapy.

Network dynamics investigation of omics-data-driven circadian-hypoxia crosstalk logical model in gallbladder cancer reveals key therapeutic target combinations

Recent findings in cancer research have pointed towards the bidirectional interaction between circadian and hypoxia pathways. However, little is known about their crosstalk mechanism. In this work, we aimed to investigate this crosstalk at a network level utilizing the omics information of gallbladder cancer. Differential gene expression and pathway enrichment analysis were used for selecting the crucial genes from both the pathways, followed by the construction of a logical crosstalk model using GINsim. Functional circuit identification and node perturbations were then performed. Significant node combinations were used to investigate the temporal behavior of the network through MaBoSS. Lastly, the model was validated using published in vitro experimentations. Four new positive circuits and a new axis viz. BMAL1/ HIF1αβ/ NANOG, responsible for stemness were identified. Through triple node perturbations viz.a. BMAL:CLOCK (KO or E1) + P53 (E1) + HIF1α (KO); b. P53 (E1) + HIF1α (KO) + MYC (E1); and c. HIF1α (KO) + MYC (E1) + EGFR (KO), the model was able to inhibit cancer growth and maintain a homeostatic condition. This work provides an architecture for drug simulation analysis to entrainment circadian rhythm and in vitro experiments for chronotherapy-related studies. Insight Box. Circadian rhythm and hypoxia are the key dysregulated processes which fuels-up the cancer growth. In the present work we have developed a gallbladder cancer (GBC) specific Boolean model, utilizing the RNASeq data from GBC dataset and tissue specific interactions. This work adequately models the bidirectional nature of interactions previously illustrated in experimental papers showing the effect of hypoxia on dysregulation of circadian rhythm and the influence of this disruption on progression towards metastasis. Through the dynamical study of the model and its response to different perturbations, we report novel triple node combinations that can be targeted to efficiently reduce GBC growth. This network can be used as a generalized framework to investigate different crosstalk pathways linked with cancer progression.

The involvement of MALAT1-ALKBH5 signaling axis into proliferation and metastasis of human papillomavirus-positive cervical cancer

Infection with high-risk human papillomavirus (HPV), for example, with types 16 and 18, is closely associated with cervical cancer development, which continues to threaten women's health globally. Although HPV oncogenes have been recognized as the main cause of transformation of normal cervical epithelial cells, non-coding RNA could also be involved in the initiation and promotion of cervical cancer development. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a well-documented long non-coding RNA (lncRNA), has been previously reported to exert roles in HPV-positive cervical cancer; however, the detailed underlying mechanism has yet to be investigated. In the present study, high expression levels of MALAT1 in HPV-Positive Cervical Cancer cells were confirmed, and silencing MALAT1 resulted in decreased rates of cell proliferation, migration, and invasion, both in vitro and in a zebrafish xenograft tumor model. Moreover, the results obtained showed that silencing MALAT1 led to down-regulation of the N6-methyladenosine (m6A) demethylase ALKBH5 via regulating miR-141-3p expression, which caused a decrease in the expression levels of matrix metalloproteinase 2 (MMP2) and MMP9 expression, thereby suppressing cell migration and invasion. Taken together, the results obtained have suggested that the MALAT-ALKBH5 signaling axis may be activated in HPV-positive cervical cancer cells, which could contribute to cell proliferation and metastasis through the regulation of key genes, such as MMP2 or MMP9. The findings of the present study should both help to improve our understanding of the underlying tumorigenic mechanisms of HPV-positive cervical cancer and be of further use in the development of potential therapeutic drugs.

The role of m6A demethylases in lung cancer: diagnostic and therapeutic implications

m6A is the most prevalent internal modification of eukaryotic mRNA, and plays a crucial role in tumorigenesis and various other biological processes. Lung cancer is a common primary malignant tumor of the lungs, which involves multiple factors in its occurrence and progression. Currently, only the demethylases FTO and ALKBH5 have been identified as associated with m6A modification. These demethylases play a crucial role in regulating the growth and invasion of lung cancer cells by removing methyl groups, thereby influencing stability and translation efficiency of mRNA. Furthermore, they participate in essential biological signaling pathways, making them potential targets for intervention in lung cancer treatment. Here we provides an overview of the involvement of m6A demethylase in lung cancer, as well as their potential application in the diagnosis, prognosis and treatment of the disease.

ALKBH5 promotes hypopharyngeal squamous cell carcinoma apoptosis by targeting TLR2 in a YTHDF1/IGF2BP2-mediated manner

Hypopharyngeal squamous cell carcinoma (HPSCC) is one of the most aggressive cancers and is notorious for its extremely poor prognosis. However, very few molecular biological studies have been performed. As a novel method of epigenetic gene modulation, N6-methyladenosine (m6A) RNA modification occurs in HPSCC. The expression of the m6A demethylase AlkB homolog 5 (ALKBH5) is frequently downregulated in human HPSCC. Furthermore, we found that ALKBH5 impaired cell proliferation by regulating human Toll-like receptor 2 (TLR2) in an m6A-dependent manner in HPSCC cells. ALKBH5 decreased TLR2 m6A modification, which could be recognized by the m6A readers IGF2BP2 and YTHDF1. IGF2BP2 facilitates TLR2 mRNA stability, whereas YTHDF1 promotes TLR2 mRNA translation. The current work uncovered a critical function of ALKBH5 in TLR2 regulation and provides a novel role for m6A demethylation of mRNA in HPSCC. The inhibition of m6A modification of ALKBH5 in HPSCC deserves further clinical investigation.

The critical roles of m6A RNA methylation in lung cancer: from mechanism to prognosis and therapy

Lung cancer, a highly malignant disease, greatly affects patients' quality of life. N6-methyladenosine (m6A) is one of the most common posttranscriptional modifications of various RNAs, including mRNAs and ncRNAs. Emerging studies have demonstrated that m6A participates in normal physiological processes and that its dysregulation is involved in many diseases, especially pulmonary tumorigenesis and progression. Among these, regulators including m6A writers, readers and erasers mediate m6A modification of lung cancer-related molecular RNAs to regulate their expression. Furthermore, the imbalance of this regulatory effect adversely affects signalling pathways related to lung cancer cell proliferation, invasion, metastasis and other biological behaviours. Based on the close association between m6A and lung cancer, various prognostic risk models have been established and novel drugs have been developed. Overall, this review comprehensively elaborates the mechanism of m6A regulation in the development of lung cancer, suggesting its potential for clinical application in the therapy and prognostic assessment of lung cancer.

RNA methylation and cellular response to oxidative stress-promoting anticancer agents

Disruption of the complex network that regulates redox homeostasis often underlies resistant phenotypes, which hinder effective and long-lasting cancer eradication. In addition, the RNA methylome-dependent control of gene expression also critically affects traits of cellular resistance to anti-cancer agents. However, few investigations aimed at establishing whether the epitranscriptome-directed adaptations underlying acquired and/or innate resistance traits in cancer could be implemented through the involvement of redox-dependent or -responsive signaling pathways. This is unexpected mainly because: i) the effectiveness of many anti-cancer approaches relies on their capacity to promote oxidative stress (OS); ii) altered redox milieu and reprogramming of mitochondrial function have been acknowledged as critical mediators of the RNA methylome-mediated response to OS. Here we summarize the current state of understanding on this topic, as well as we offer new perspectives that might lead to original approaches and strategies to delay or prevent the problem of refractory cancer and tumor recurrence.

Epitranscriptomics in the development, functions, and disorders of cancer stem cells

Biomolecular modifications play an important role in the development of life, and previous studies have investigated the role of DNA and proteins. In the last decade, with the development of sequencing technology, the veil of epitranscriptomics has been gradually lifted. Transcriptomics focuses on RNA modifications that affect gene expression at the transcriptional level. With further research, scientists have found that changes in RNA modification proteins are closely linked to cancer tumorigenesis, progression, metastasis, and drug resistance. Cancer stem cells (CSCs) are considered powerful drivers of tumorigenesis and key factors for therapeutic resistance. In this article, we focus on describing RNA modifications associated with CSCs and summarize the associated research progress. The aim of this review is to identify new directions for cancer diagnosis and targeted therapy.

Effect of N6-methyladenosine (m6A) regulator-related immunogenes on the prognosis and immune microenvironment of breast cancer

Background

Breast cancer is one of the most common malignant tumor and the prognosis remains unsatisfying. Various studies demonstrate that m6A modulators are new predictors of prognosis in immune microenvironment. We aimed to identify several m6A regulator-related immunogenes and explore the relationship between m6A regulator-related immunogenes and breast cancer prognosis as well as the tumor immune microenvironment (TIME).

Methods

RNA sequencing data and clinical information on 21 m6A regulators in 1,047 breast cancer samples were downloaded from The Cancer Genome Atlas (TCGA), and immune gene data were downloaded from InnateDB. Kaplan-Meier survival analysis was conducted with log-rank test using the survival package. An m6A-related immunogene-prognostic signature was then constructed, followed by immune infiltration and checkpoint analyses.

Results

A risk prognostic signature of m6A regulator-related immunogenes, including TOX, PSME2, MCTS1, NFKBIE, SH3BP4, RSPH1, JAK1, MLLT4, and PTGES3, was constructed. Furthermore, univariate and multivariate Cox regression analyses suggested that the tumor stage and risk score could be independent prognostic factors for patients with breast cancer. Immune infiltration analysis showed that the infiltration levels of T cells, memory B cells, activated NK cells, and macrophages between the high- and low-risk groups were significantly different. In addition, checkpoint analyses demonstrated that the levels of immune checkpoint genes, such as those of LAG3, PDCD1, CTLA4, and HAVCR2, were downregulated in the high-risk group compared to those in the low-risk group.

Conclusions

Our findings suggest that the m6A regulator-related risk prognostic signature can predict the prognosis of breast cancer and that it is related to the immune microenvironment.

The effects of epithelial-mesenchymal transitions in COPD induced by cigarette smoke: an update

Cigarette smoke is a complex aerosol containing a large number of compounds with a variety of toxicity and carcinogenicity. Long-term exposure to cigarette smoke significantly increases the risk of a variety of diseases, including chronic obstructive pulmonary disease (COPD) and lung cancer. Epithelial–mesenchymal transition (EMT) is a unique biological process, that refers to epithelial cells losing their polarity and transforming into mobile mesenchymal cells, playing a crucial role in organ development, fibrosis, and cancer progression. Numerous recent studies have shown that EMT is an important pathophysiological process involved in airway fibrosis, airway remodeling, and malignant transformation of COPD. In this review, we summarized the effects of cigarette smoke on the development and progression of COPD and focus on the specific changes and underlying mechanisms of EMT in COPD induced by cigarette smoke. We spotlighted the signaling pathways involved in EMT induced by cigarette smoke and summarize the current research and treatment approaches for EMT in COPD, aiming to provide ideas for potential new treatment and research directions.

Current treatments for non-small cell lung cancer

Despite improved methods of diagnosis and the development of different treatments, mortality from lung cancer remains surprisingly high. Non-small cell lung cancer (NSCLC) accounts for the large majority of lung cancer cases. Therefore, it is important to review current methods of diagnosis and treatments of NSCLC in the clinic and preclinic. In this review, we describe, as a guide for clinicians, current diagnostic methods and therapies (such as chemotherapy, chemoradiotherapy, targeted therapy, antiangiogenic therapy, immunotherapy, and combination therapy) for NSCLC.

RNA N6-Methyladenine Modification, Cellular Reprogramming, and Cancer Stemness

N⁶-Methyladenosine (m⁶A) is the most abundant modification on eukaryote messenger RNA and plays a key role in posttranscriptional regulation of RNA metabolism including splicing, intracellular transport, degradation, and translation. m⁶A is dynamically regulated by methyltransferases (writers), RNA-binding proteins (readers), and demethylases (erasers). Recent studies demonstrate that perturbation of m⁶A regulators remarkably influences cell fate transitions through rewiring various biological processes, such as growth, differentiation, and survival. Moreover, aberrant m⁶A modification is implicated in a variety of diseases, in particular cancer. In this review, we describe the functional linkage of m⁶A modifications to cellular reprogramming and cancer stemness properties.