SETD1A Promotes Proliferation of Castration-Resistant Prostate Cancer Cells via FOXM1 Transcription

Molecular mechanisms and targeted therapy for the metastasis of prostate cancer to the bones (Review)

The incidence of prostate cancer (PCa) is increasing, making it one of the prevalent malignancies among men. Metastasis of PCa to the bones poses the greatest danger to patients, potentially resulting in treatment ineffectiveness and mortality. At present, the management of patients with bone metastasis focuses primarily on providing palliative care. Research has indicated that the spread of PCa to the bones occurs through the participation of numerous molecules and their respective pathways. Gaining knowledge regarding the molecular processes involved in bone metastasis may result in the development of innovative and well‑tolerated therapies, ultimately enhancing the quality of life and prognosis of patients. The present article provides the latest overview of the molecular mechanisms involved in the formation of bone metastatic tumors from PCa. Additionally, the clinical outcomes of targeted drug therapies for bone metastasis are thoroughly analyzed. Finally, the benefits and difficulties of targeted therapy for bone metastasis of PCa are discussed, aiming to offer fresh perspectives for treatment.

PLEK2 activates the PI3K/AKT signaling pathway to drive lung adenocarcinoma progression by upregulating SPC25

Lung adenocarcinoma (LUAD) is the most common subtype of NSCLC, characterized by poor prognosis and frequently diagnosed at advanced. While previous studies have demonstrated pleckstrin-2 (PLEK2) as aberrantly expressed and implicated in tumorigenesis across various tumor types, including LUAD, the molecular mechanisms underlying PLEK2-mediated LUAD progression remain incompletely understood. In this study, we obtained data from The Cancer Genome Atlas (TCGA) database to assess PLEK2 expression in LUAD, a finding further confirmed through analysis of human tissue specimens. PLEK2-silenced LUAD cellular models were subsequently constructed to examine the functional role of PLEK2 both in vitro and in vivo. Our results showed elevated PLEK2 expression in LUAD, correlating with poor patients' prognosis. PLEK2 knockdown led to a significant suppression of LUAD cell proliferation and migration, accompanied by enhanced apoptosis. Moreover, tumor growth in mice injected with PLEK2-silencing LUAD cells was impaired. Gene expression profiling and Co-IP assays suggested direct interaction between PLEK2 and SPC25, with downregulation of SPC25 similarly impairing cell proliferation and migration. Additionally, we revealed phosphoinositide 3-kinase (PI3K)/AKT signaling activation as requisite for PLEK2-induced malignant phenotypes in LUAD. Collectively, our findings underscore PLEK2's oncogenic potential in LUAD, suggesting its utility as a prognostic indicator and therapeutic target for LUAD management.

CDCA5 accelerates progression of breast cancer by promoting the binding of E2F1 and FOXM1

BACKGROUND

Breast cancer is one of the most common malignant tumors in women. Cell division cycle associated 5 (CDCA5), a master regulator of sister chromatid cohesion, was reported to be upregulated in several types of cancer. Here, the function and regulation mechanism of CDCA5 in breast cancer were explored.

METHODS

CDCA5 expression was identified through immunohistochemistry staining in breast cancer specimens. The correlation between CDCA5 expression with clinicopathological features and prognosis of breast cancer patients was analyzed using a tissue microarray. CDCA5 function in breast cancer was explored in CDCA5-overexpressed/knockdown cells and mice models. Co-IP, ChIP and dual-luciferase reporter assay assays were performed to clarify underlying molecular mechanisms.

RESULTS

We found that CDCA5 was expressed at a higher level in breast cancer tissues and cell lines, and overexpression of CDCA5 was significantly associated with poor prognosis of patients with breast cancer. Moreover, CDCA5 knockdown significantly suppressed the proliferation and migration, while promoted apoptosis in vitro. Mechanistically, we revealed that CDCA5 played an important role in promoting the binding of E2F transcription factor 1 (E2F1) to the forkhead box M1 (FOXM1) promoter. Furthermore, the data of in vitro and in vivo revealed that depletion of FOXM1 alleviated the effect of CDCA5 overexpression on breast cancer. Additionally, we revealed that the Wnt/β-catenin signaling pathway was required for CDCA5 induced progression of breast cancer.

CONCLUSIONS

We suggested that CDCA5 promoted progression of breast cancer via CDCA5/FOXM1/Wnt axis, CDCA5 might serve as a novel therapeutic target for breast cancer treatment.

Deciphering the genetic and epigenetic architecture of prostate cancer

Prostate cancer, one of the most frequently diagnosed cancers in men, leads to significant mortality worldwide. Its study is important due to the complexity and diversity in its progression, highlighting the urgent need for improved therapeutic strategies. This chapter probes into the genetic and epigenetic factors influencing prostate cancer progression, underscoring the importance of understanding the disease's molecular fundamentals for the development of targeted therapies. It specifically reviews the role of key genetic mutations in genes such as Androgen Receptor, TP53, SPOP, FOXA1 and PTEN which are crucial for the disease onset and a progression. Furthermore, it examines the impact of epigenetic modifications, including DNA methylation and histone modification, which contribute to the cancer's progression by affecting gene expression and cellular behavior. Further, in this chapter we delve into the underlying signaling mechanism, the advancements in targeting genetic and epigenetic alterations in prostate cancer. These findings have revealed promising targets for therapeutic advancements, aiming to understand and identify promising avenues for future therapies. This chapter improves our current understanding of prostate cancer genetic and epigenetic landscape, emphasizing the necessity of advancing our knowledge to refine and expand treatment options for prostate cancer patients.

Epigenetic regulation of androgen dependent and independent prostate cancer

Prostate cancer is one of the most common malignancies among men worldwide. Besides genetic alterations, epigenetic modulations including DNA methylation, histone modifications and miRNA mediated alteration of gene expression are the key driving forces for the prostate tumor development and cancer progression. Aberrant expression and/or the activity of the epigenetic modifiers/enzymes, results in aberrant expression of genes involved in DNA repair, cell cycle regulation, cell adhesion, apoptosis, autophagy, tumor suppression and hormone response and thereby disease progression. Altered epigenome is associated with prostate cancer recurrence, progression, aggressiveness and transition from androgen-dependent to androgen-independent phenotype. These epigenetic modifications are reversible and various compounds/drugs targeting the epigenetic enzymes have been developed that are effective in cancer treatment. This chapter focuses on the epigenetic alterations in prostate cancer initiation and progression, listing different epigenetic biomarkers for diagnosis and prognosis of the disease and their potential as therapeutic targets. This chapter also summarizes different epigenetic drugs approved for prostate cancer therapy and the drugs available for clinical trials.

AURKA promotes renal cell carcinoma progression via regulation of CCNB1 transcription

AURKA is a member of the serine/threonine kinase family and its kinase activity is crucial for the progression of mitosis. Recent studies have highlighted the therapeutic significance of AURKA inhibition in multiple cancer types. However, the specific mechanisms by which AURKA contributes to the progression of renal cell carcinoma (RCC) have not been fully elucidated. In this study, AURKA expression level was identified in human RCC tissues by immunohistochemical (IHC) staining. The function of AURKA on cell malignant phenotypes was evaluated in vitro after AURKA inhibition. The subcutaneous xenograft was conducted to confirm the in vivo effect of AURKA knockdown on growth of RCC cells. Finally, Co-IP, luciferase assay and ChIP experiments were performed to reveal the regulatory mechanism of AURKA on CCNB1. Our results showed a significant upregulation of AURKA in RCC tissues and cell lines, and a high AURKA expression was associated with poor prognosis. AURKA knockdown inhibited RCC cell proliferation and migration, induced cell apoptosis, and led to G1/G2 phase arrest. This effect was further confirmed by the use of an AURKA inhibitor. Mechanistically, AURKA interacted with E2F1, and subsequently recruited it to the promoter region of CCNB1. CCNB1 expression was essential for AURKA-induced RCC progression. Collectively, our results suggested that AURKA plays an important role in development of RCC via regulating CCNB1 transcription.

Oncogenic role of FOXM1 in human prostate cancer (Review)

Prostate cancer is the leading cause of cancer‑related mortality among men worldwide. In particular, castration‑resistant prostate cancer presents a formidable clinical challenge and emphasizes the need to develop novel therapeutic strategies. Forkhead box M1 (FOXM1) is a multifaceted transcription factor that is implicated in the acquisition of the multiple cancer hallmark capabilities in prostate cancer cells, including sustaining proliferative signaling, resisting cell death and the activation of invasion and metastasis. Elevated FOXM1 expression is frequently observed in prostate cancer, and in particular, FOXM1 overexpression is closely associated with poor clinical outcomes in patients with prostate cancer. In the present review, recent advances in the understanding of the oncogenic role of deregulated FOXM1 expression in prostate cancer were highlighted. In addition, the molecular mechanisms by which FOXM1 regulates prostate cancer development and progression were described, thereby providing knowledge and a conceptual framework for FOXM1. The present review also provided valuable insight into the inherent challenges associated with translating biomedical knowledge into effective therapeutic strategies for prostate cancer.

FOXM1: A small fox that makes more tracks for cancer progression and metastasis

Transcription factors (TFs) are indispensable for the modulation of various signaling pathways associated with normal cell homeostasis and disease conditions. Among cancer-related TFs, FOXM1 is a critical molecule that regulates multiple aspects of cancer cells, including growth, metastasis, recurrence, and stem cell features. FOXM1 also impact the outcomes of targeted therapies, chemotherapies, and immune checkpoint inhibitors (ICIs) in various cancer types. Recent advances in cancer research strengthen the cancer-specific role of FOXM1, providing a rationale to target FOXM1 for developing targeted therapies. This review compiles the recent studies describing the pivotal role of FOXM1 in promoting metastasis of various cancer types. It also implicates the contribution of FOXM1 in the modulation of chemotherapeutic resistance, antitumor immune response/immunotherapies, and the potential of small molecule inhibitors of FOXM1.

Histone modifications in drug-resistant cancers: From a cancer stem cell and immune evasion perspective

The development and immune evasion of cancer stem cells (CSCs) limit the efficacy of currently available anticancer therapies. Recent studies have shown that epigenetic reprogramming regulates the expression of characteristic marker proteins and tumor plasticity associated with cancer cell survival and metastasis in CSCs. CSCs also possess unique mechanisms to evade external attacks by immune cells. Hence, the development of new strategies to restore dysregulated histone modifications to overcome cancer resistance to chemotherapy and immunotherapy has recently attracted attention. Restoring abnormal histone modifications can be an effective anticancer strategy to increase the therapeutic effect of conventional chemotherapeutic and immunotherapeutic drugs by weakening CSCs or by rendering them in a naïve state with increased sensitivity to immune responses. In this review, we summarize recent findings regarding the role of histone modifiers in the development of drug-resistant cancer cells from the perspectives of CSCs and immune evasion. In addition, we discuss attempts to combine currently available histone modification inhibitors with conventional chemotherapy or immunotherapy.

H3 histone methylation landscape in male urogenital cancers: from molecular mechanisms to epigenetic biomarkers and therapeutic targets

During the last decades, male urogenital cancers (including prostate, renal, bladder and testicular cancers) have become one of the most frequently encountered malignancies affecting all ages. While their great variety has promoted the development of various diagnosis, treatment and monitoring strategies, some aspects such as the common involvement of epigenetic mechanisms are still not elucidated. Epigenetic processes have come into the spotlight in the past years as important players in the initiation and progression of tumors, leading to a plethora of studies highlighting their potential as biomarkers for diagnosis, staging, prognosis, and even as therapeutic targets. Thus, fostering research on the various epigenetic mechanisms and their roles in cancer remains a priority for the scientific community. This review focuses on one of the main epigenetic mechanisms, namely, the methylation of the histone H3 at various sites and its involvement in male urogenital cancers. This histone modification presents a great interest due to its modulatory effect on gene expression, leading either to activation (e.g., H3K4me3, H3K36me3) or repression (e.g., H3K27me3, H3K9me3). In the last few years, growing evidence has demonstrated the aberrant expression of enzymes that methylate/demethylate histone H3 in cancer and inflammatory diseases, that might contribute to the initiation and progression of such disorders. We highlight how these particular epigenetic modifications are emerging as potential diagnostic and prognostic biomarkers or targets for the treatment of urogenital cancers.

Biomarkers for Prostate Cancer Bone Metastasis Detection and Prediction

Prostate cancer (PCa) causes deaths worldwide, ranking second after lung cancer. Bone metastasis (BM) frequently results from advanced PCa, affecting approximately 90% of patients, and it also often results in severe skeletal-related events. Traditional diagnostic methods for bone metastases, such as tissue biopsies and imaging, have substantial drawbacks. This article summarizes the significance of biomarkers in PCa accompanied with BM, including (1) bone formation markers like osteopontin (OPN), pro-collagen type I C-terminal pro-peptide (PICP), osteoprotegerin (OPG), pro-collagen type I N-terminal pro-peptide (PINP), alkaline phosphatase (ALP), and osteocalcin (OC); (2) bone resorption markers, including C-telopeptide of type I collagen (CTx), N-telopeptide of type I collagen (NTx), bone sialoprotein (BSP), tartrate-resistant acid phosphatase (TRACP), deoxypyridinoline (D-PYD), pyridoxine (PYD), and C-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP); (3) prostate-specific antigen (PSA); (4) neuroendocrine markers, such as chromogranin A (CgA), neuron-specific enolase (NSE), and pro-gastrin releasing peptide (ProGRP); (5) liquid biopsy markers, such as circulating tumor cells (CTCs), microRNA (miRNA), circulating tumor DNA (ctDNA), and cell-free DNA (cfDNA) and exosomes. In summary, some of these markers are already in widespread clinical use, while others still require further laboratory or clinical studies to validate their value for clinical application.

A small molecule compound that inhibits blue light-induced retinal damage via activation of autophagy

Dry age-related macular degeneration (AMD) is a type of disease that causes visual impairment due to changes in the macula located in the center of the retina. The accumulation of drusen under the retina is also a characteristic of dry AMD. In this study, we identified a compound (JS-017) that can potentially degrade N-retinylidene-N-retinylethanolamine (A2E), one of the components of lipofuscin, using fluorescence-based screening, which measures A2E degradation in human retinal pigment epithelial cells. JS-017 effectively degraded A2E in ARPE-19 cells and consequently suppressed the activation of the NF-κB signaling pathway and expression of inflammatory and apoptosis genes induced by blue light (BL). Mechanistically, JS-017 induced LC3-II formation and improved autophagic flux in ARPE-19 cells. Additionally, the A2E degradation activity of JS-017 was found to be decreased in autophagy-related 5 protein-depleted ARPE-19 cells, suggesting that autophagy was required for A2E degradation mediated by JS-017. Finally, JS-017 exhibited an improvement in BL-induced retinal damage measured through fundus examination in an in vivo retinal degeneration mouse model. The thickness of the outer nuclear layer and inner/external segments, which was decreased upon exposure to BL irradiation, was also restored upon JS-017 treatment. Altogether, we demonstrated that JS-017 protected human retinal pigment epithelium (RPE) cells from A2E and BL-induced damage by degrading A2E via the activation of autophagy. The results suggest the feasibility of a novel A2E-degrading small molecule as a therapeutic agent for retinal degenerative diseases.

Molecular predictors of metastasis in patients with prostate cancer

INTRODUCTION

Prostate cancer is a serious threat to the health of older adults worldwide. The quality of life and survival time of patients sharply decline once metastasis occurs. Thus, early screening for prostate cancer is very advanced in developed countries. The detection methods used include Prostate-specific antigen (PSA) detection and digital rectal examination. However, the lack of universal access to early screening in some developing countries has resulted in an increased number of patients presenting with metastatic prostate cancer. In addition, the treatment methods for metastatic and localized prostate cancer are considerably different. In many patients, early-stage prostate cancer cells often metastasize due to delayed observation, negative PSA results, and delay in treatment time. Therefore, the identification of patients who are prone to metastasis is important for future clinical studies.

AREAS COVERED

this review introduced a large number of predictive molecules related to prostate cancer metastasis. These molecules involve the mutation and regulation of tumor cell genes, changes in the tumor microenvironment, and the liquid biopsy.

EXPERT OPINION

In next decade, PSMA PET/CT and liquid biopsy will be the excellent predicting tools, while ¹⁷⁷ Lu- PSMA-RLT will be showed excellent anti-tumor efficacy in mPCa patients.

Identification of Chromatin Regulatory Factors Related to Immunity and Treatment of Alzheimer's Disease

Alzheimer's disease is one of the common neurodegenerative diseases in the elderly, which mainly manifests as progressively severe cognitive impairment, which seriously affects the quality of life of patients. Chromatin regulators have been shown to be associated with a variety of biological processes, and we mainly explore the relationship between chromatin regulators and Alzheimer's disease. Eight hundred seventy chromatin regulators were collected from previous studies, and data related to Alzheimer's disease patients were downloaded from the GEO database. Finally, we screened chromatin regulators related to Alzheimer's disease immunity, established prediction models, and screened related drugs and miRNAs. We screened 160 differentially expressed CRs, constructed an interaction network, obtained 10 hub genes, successfully constructed a prediction model based on immune-related 5 CRs, and obtained 520 related drugs and 3 related miRNA, which provided an idea for the treatment of Alzheimer's disease. Our study identified 5 chromatin regulators related to Alzheimer's disease, which are expected to be new targets for Alzheimer's disease immunotherapy.

Epigenetic (De)regulation in Prostate Cancer

Prostate cancer (PCa) is a heterogeneous disease exhibiting both genetic and epigenetic deregulations. Epigenetic alterations are defined as changes not based on DNA sequence, which include those of DNA methylation, histone modification, and chromatin remodeling. Androgen receptor (AR) is the main driver for PCa and androgen deprivation therapy (ADT) remains a backbone treatment for patients with PCa; however, ADT resistance almost inevitably occurs and advanced diseases develop termed castration-resistant PCa (CRPC), due to both genetic and epigenetic changes. Due to the reversible nature of epigenetic modifications, inhibitors targeting epigenetic factors have become promising anti-cancer agents. In this chapter, we focus on recent studies about the dysregulation of epigenetic regulators crucially involved in the initiation, development, and progression of PCa and discuss the potential use of inhibitors targeting epigenetic modifiers for treatment of advanced PCa.

Identification of a novel target of SETD1A histone methyltransferase and the clinical significance in pancreatic cancer

Although histone H3K4 methyltransferase SETD1A is overexpressed in various cancer types, the molecular mechanism underlying its overexpression and its target genes in pancreatic ductal adenocarcinoma (PDAC) remain unclarified. We conducted immunohistochemical staining for SETD1A in 105 human PDAC specimens to assess the relationship between SETD1A overexpression and clinicopathological features. The function and target genes of SETD1A were investigated using human pancreatic cancer cell lines. SETD1A expression was upregulated in 51.4% of patients with PDAC and was an independent prognostic factor associated with shorter disease-free survival after resection (p < 0.05). Knockdown and overexpression of SETD1A showed that SETD1A plays a crucial role in increasing the proliferation and motility of PDAC cells. SETD1A overexpression increased tumorigenicity. RNA sequencing of SETD1A-knockdown cells revealed downregulation of RUVBL1, an oncogenic protein ATP-dependent DNA helicase gene. ChIP analysis revealed that SETD1A binds to the RUVBL1 promoter region, resulting in increased H3K4me3 levels. Knockdown of RUVBL1 showed inhibition of cell proliferation, migration, and invasion of PDAC cells, which are similar biological effects to SETD1A knockdown. High expression of both SETD1A and RUVBL1 was an independent prognostic factor not only for disease-free survival but also for overall survival (p < 0.05). In conclusion, we identified RUVBL1 as a novel downstream target gene of the SETD1A-H3K4me3 pathway. Co-expression of SETD1A and RUVBL1 is an important factor for predicting the prognosis of patients with PDAC.

Construction of Bone Metastasis-Specific Regulation Network Based on Prognostic Stemness-Related Signatures in Prostate Cancer

Background

We planned to uncover the cancer stemness-related genes (SRGs) in prostate cancer (PCa) and its underlying mechanism in PCa metastasis.

Methods

We acquired the RNA-seq data of 406 patients with PCa from the TCGA database. Based on the mRNA stemness index (mRNAsi) calculated by one-class logistic regression (OCLR) algorithm, SRGs in PCa were extracted by WGCNA. Univariate and multivariate regression analyses were applied to uncover OS-associated SRGs. Gene Set Variation Analysis (GSVA), Gene Set Enrichment Analysis (GSEA), and Pearson's correlation analysis were performed to discover the possible mechanism of PCa metastasis. The significantly correlated transcription factors of OS-associated SRGs were also identified by Pearson's correlation analysis. ChIP-seq was applied to validate the binding relationship of TFs and OS-associated SRGs and spatial transcriptome and single-cell sequencing were performed to uncover the location of key biomarkers expression. Lastly, we explored the specific inhibitors for SRGs using CMap algorithm.

Results

We identified 538 differentially expressed genes (DEGs) between non-metastatic and metastatic PCa. Furthermore, OS-associated SRGs were identified. The Pearson correlation analysis revealed that FOXM1 was significantly correlated with NEIL3 (correlation efficient =0.89, p < 0.001) and identified hallmark_E2F_targets as the potential pathway mechanism of NEIL3 promoting PCa metastasis (correlation efficient =0.58, p < 0.001). Single-cell sequencing results indicated that FOXM1 regulating NEIL3 may get involved in the antiandrogen resistance of PCa. Rottlerin was discovered to be a potential target drug for PCa.

Conclusion

We constructed a regulatory network based on SRGs associated with PCa metastasis and explored possible mechanism.

Comprehensive analysis of the functional and prognostic value of E2F transcription factors in human prostate cancer through data mining and experimental validation

Background

A growing body of evidence shows that E2F transcription factors play a significant role in the tumorigenesis of prostate cancer. However, their functional and prognostic value has not been fully illustrated. Therefore, we used bioinformatics methods to further analyze the possible roles of E2F transcription factors in the development and progression of prostate cancer.

Methods

We explored the expression levels of E2F transcription factors using data from The Cancer Genome Atlas (TCGA) and Oncomine database in paired and unpaired samples. The clinical correlation and prognostic value of E2F transcription factors were assessed. Using the R package “pROC”, we judged the diagnostic value of E2F transcription factors. The online website tool cBioPortal was also employed to find possible gene alterations of E2F transcription factors in samples from TCGA. The R package “clusterprofiler” was used to conduct functional analysis. Moreover, we also used the Tumor Immune Estimation Resource to search for the associations between E2F transcription factors and the infiltration levels of 6 kinds of immune cells. Finally, quantitative real-time polymerase chain reaction (PCR) was conducted to validate the expression levels of E2F transcription factors in human paired prostate tissues.

Results

E2F1/2/3/5 messenger RNA (mRNA) expression levels were higher in prostate cancer tissues than in normal tissues, while E2F4 and E2F6 mRNA expression levels were lower (P<0.05). All E2F transcription factors were associated with clinical parameters. Kaplan-Meier analysis revealed that E2F1/4/6/8 were notably associated with the overall survival of patients with prostate cancer (P<0.05). Receiver operating characteristic (ROC) curve results showed that except for E2F7, the other E2F transcription factors had diagnostic value for prostate cancer (P<0.05). We further found close associations between E2F transcription factors and the infiltration levels of immune cells. The results of quantitative real-time PCR were consistent with those from public databases.

Conclusions

E2F transcription factor family members are differentially expressed in prostate cancer and are significantly related to the prognosis of patients, suggesting that they may be adopted as biomarkers for prognosis prediction and the treatment of prostate cancer.

Transcriptome Analysis of Long-Term Exposure to Blue Light in Retinal Pigment Epithelial Cells

Dry age-related macular degeneration (AMD) is a type of progressive blindness that is primarily due to dysfunction and the loss of retinal pigment epithelium (RPE). The accumulation of N-retinylidene-N-retinylethanolamine (A2E), a by-product of the visual cycle, causes RPE and photoreceptor degeneration that impairs vision. Genes associated with dry AMD have been identified using a blue light model of A2E accumulation in the retinal pigment epithelium and transcriptomic studies of retinal tissue from patients with AMD. However, dry macular degeneration progresses slowly, and current approaches cannot reveal changes in gene transcription according to stages of AMD progression. Thus, they are limited in terms of identifying genes responsible for pathogenesis. Here, we created a model of long-term exposure to identify temporally-dependent changes in gene expression induced in human retinal pigment epithelial cells (ARPE-19) exposed to blue light and a non-cytotoxic dose of A2E for 120 days. We identified stage-specific genes at 40, 100, and 120 days, respectively. The expression of genes corresponding to epithelial-mesenchymal transition (EMT) during the early stage, glycolysis and angiogenesis during the middle stage, and apoptosis and inflammation pathways during the late stage was significantly altered by A2E and blue light. Changes in the expression of genes at the late stages of the EMT were similar to those found in human eyes with late-stage AMD. Our results provide further insight into the pathogenesis of dry AMD induced by blue light and a novel model in vitro with which relevant genes can be identified in the future.

FLII and MLL1 Cooperatively Regulate Aryl Hydrocarbon Receptor-Mediated Transcription in ARPE-19 Cells

Aryl hydrocarbon receptors (AHRs), a class of ligand-dependent nuclear receptors that regulate cellular responses by inducing the expression of various target genes in response to external signals, are implicated in maintaining retinal tissue homeostasis. Previous studies have shown that the regulation of AHR-induced gene expression requires transcriptional co-regulators. However, it is not yet clear how chromatin remodelers, histone methyltransferases and coactivators interact during AHR-mediated gene expression in human retinal cells. In this study, we reveal that the histone methyltransferase MLL1 and the coactivator FLII are involved in AHR-mediated gene expression in retinal pigment epithelial cells. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) significantly increased the expression of CYP1A1, CYP1B1 and AHRR in ARPE-19 cells, whereas FLII or MLL1 depletion significantly reduced the expression of these genes induced by TCDD. Mechanistically, FLII binds to AHR in a ligand-dependent manner in ARPE-19 cells. In particular, the binding of FLII to MLL1 occurs through the GelB domain of FLII. In addition, MLL1 binds to AHR in a ligand-independent manner. FLII is involved in the recruitment of the BRG1 chromatin remodeler and MLL1 histone methyltransferase to the AHR-regulated CYP1A1 gene region in ARPE-19 cells and consequently, plays an important role in RNA polymerase II binding and transcriptional activity by modulating chromatin accessibility. Our results identify the functions and mechanisms of action of FLII and MLL1 in AHR-induced gene expression in human retinal pigment epithelial cells.

An SETD1A/Wnt/β-catenin feedback loop promotes NSCLC development

Background

SETD1A, a member of SET1/MLL family H3K4 methyltransferases, is involved in the tumorigenesis of numerous cancers. However, the biological role and mechanism of SETD1A in non-small cell lung cancer (NSCLC) remain to be elucidated.

Methods

The expression of SETD1A, NEAT1, EZH2, and β-catenin in NSCLC tissues and cell lines was detected by qRT-PCR, immunohistochemistry and western blotting. The regulatory mechanisms were validated by chromatin immunoprecipitation, co-immunoprepitation and luciferase reporter assay. The self-renewal, cisplatin sensitivity and tumorigenesis of NSCLC cells were analyzed using sphere formation, CCK-8, colony formation assays and xenograft tumor models.

Results

SETD1A expression was significantly increased in NSCLC and its overexpression predicted a poor prognosis of patients with NSCLC. Functional experiments showed that SETD1A positively regulated cancer stem cell property and negatively regulated cisplatin sensitivity in NSCLC cells via the Wnt/β-catenin pathway. Next, we found that SETD1A positively regulated the Wnt/β-catenin pathway via interacting with and stabilizing β-catenin. The SET domain is dispensable for the interaction between SETD1A and β-catenin. Furthermore, we identified that SETD1A bound to the promoters of NEAT1 and EZH2 to activate gene transcription by inducing H3K4me3 enrichment. Rescue experiments showed that SETD1A promoted the Wnt/β-catenin pathway and exerted its oncogenic functions in NSCLC, at least, partly through NEAT1 and EZH2 upregulation. In addition, SETD1A was proven to be a direct target of the Wnt/β-catenin pathway, thus forming a positive feedback loop in NSCLC cells.

Conclusion

SETD1A and Wnt/β-catenin pathway form a positive feedback loop and coordinately contribute to NSCLC progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02119-x.

Histone H3K4 Methyltransferases as Targets for Drug-Resistant Cancers

The KMT2 (MLL) family of proteins, including the major histone H3K4 methyltransferase found in mammals, exists as large complexes with common subunit proteins and exhibits enzymatic activity. SMYD, another H3K4 methyltransferase, and SET7/9 proteins catalyze the methylation of several non-histone targets, in addition to histone H3K4 residues. Despite these structural and functional commonalities, H3K4 methyltransferase proteins have specificity for their target genes and play a role in the development of various cancers as well as in drug resistance. In this review, we examine the overall role of histone H3K4 methyltransferase in the development of various cancers and in the progression of drug resistance. Compounds that inhibit protein-protein interactions between KMT2 family proteins and their common subunits or the activity of SMYD and SET7/9 are continuously being developed for the treatment of acute leukemia, triple-negative breast cancer, and castration-resistant prostate cancer. These H3K4 methyltransferase inhibitors, either alone or in combination with other drugs, are expected to play a role in overcoming drug resistance in leukemia and various solid cancers.

GTSE1 promotes prostate cancer cell proliferation via the SP1/FOXM1 signaling pathway

G2 and S phase-expressed-1 (GTSE1) has been implicated in the pathogenesis of several malignant tumors. However, its specific role in prostate cancer (PCa) remains unclear. In this study, RNA-Seq data from patients with PCa and controls were downloaded from the FIREBROWSE database, and it was found that the GTSE1 mRNA level was significantly upregulated in PCa. Moreover, patients with higher GTSE1 mRNA levels had higher Gleason scores (P < 0.001), a more advanced pT stage (P = 0.011), and a more advanced pN stage (P = 0.006) as well as a shorter time to biochemical recurrence (P = 0.005). In addition, overexpression of GTSE1 could promote proliferation in LNCaP cells, whereas silencing GTSE1 could inhibit the growth of C4-2 cells in vitro and in vivo. Mechanistically, GTSE1 enhanced the expression of FOXM1 by upregulating the SP1 protein level, a transcription factor of FOXM1, which ultimately promoted PCa cell proliferation. In summary, GTSE1 is a new candidate oncogene in the development and progression of PCa, and it can promote PCa cell proliferation via the SP1/FOXM1 signaling pathway.

Methyltransferase SET domain family and its relationship with cardiovascular development and diseases

Abnormal epigenetic modification is closely related to the occurrence and development of cardiovascular diseases. The SET domain (SETD) family is an important epigenetic modifying enzyme containing SETD. They mainly affect gene expression by methylating H3K4, H3K9, H3K36 and H4K20. Additionally, the SETD family catalyzes the methylation of non-histone proteins, thereby affects the signal transduction of signal transduction and activator of transcription (STAT) 1, Wnt/β-catenin, hypoxia-inducible factor (HIF)-1α and Hippo/YAP pathways. The SETD family has the following regulatory effects on cardiovascular development and diseases: regulating coronary artery formation and cardiac development; protecting cardiac tissue from ischemia reperfusion injury; regulating inflammation, oxidative stress and apoptosis in cardiovascular complications of diabetes; participating in the formation of pulmonary hypertension; regulating thrombosis, cardiac hypertrophy and arrhythmia. This article summarizes the basic structures, expression regulation mechanisms and the role of existing SETD family members in cardiovascular development and diseases, in order to provide a basis for understanding the molecular mechanism of cardiovascular disease and exploring the therapeutic targets.