The emerging role of PI3K/AKT-mediated epigenetic regulation in cancer

Sevoflurane postconditioning attenuates cardiomyocytes hypoxia/reoxygenation injury via PI3K/AKT pathway mediated HIF-1α to regulate the mitochondrial dynamic balance

BACKGROUND

Myocardial ischemia-reperfusion injury (I/RI) is a major cause of perioperative cardiac-related adverse events and death. Studies have shown that sevoflurane postconditioning (SpostC), which attenuates I/R injury and exerts cardioprotective effects, regulates mitochondrial dynamic balance via HIF-1α, but the exact mechanism is unknown. This study investigates whether the PI3K/AKT pathway in SpostC regulates mitochondrial dynamic balance by mediating HIF-1α, thereby exerting myocardial protective effects.

METHODS

The H9C2 cardiomyocytes were cultured to establish the hypoxia-reoxygenation (H/R) model and randomly divided into 4 groups: Control group, H/R group, sevoflurane postconditioning (H/R + SpostC) group and PI3K/AKT blocker (H/R + SpostC + LY) group. Cell survival rate was determined by CCK-8; Apoptosis rate was determined by flow cytometry; mitochondrial membrane potential was evaluated by Mito Tracker™ Red; mRNA expression levels of AKT, HIF-1α, Opa1and Drp1 were detected by quantitative real-time polymerase chain reaction (qRT-PCR); Western Blot assay was used to detect the protein expression levels of AKT, phosphorylated AKT (p-AKT), HIF-1α, Opa1 and Drp1.

RESULTS

Compared with the H/R group, the survival rate of cardiomyocytes in the H/R + SpostC group increased, the apoptosis rate decreased and the mitochondrial membrane potential increased. qRT-PCR showed that the mRNA expression of HIF-1α and Opa1 were higher in the H/R + SpostC group compared with the H/R group, whereas the transcription level of Drp1 was lower in the H/R + SpostC group. In the H/R + SpostC + LY group, the mRNA expression of HIF-1α was lower than the H/R + SpostC group. There was no difference in the expression of Opa1 mRNA between the H/R group and the H/R + SpostC + LY group. WB assay results showed that compared with the H/R group, the protein expression levels of HIF-1α, Opa1, P-AKT were increased and Drp1 protein expression levels were decreased in the H/R + SpostC group. HIF-1α, P-AKT protein expression levels were decreased in the H/R + SpostC + LY group compared to the H/R + SpostC group.

CONCLUSION

SpostC mediates HIF-1α-regulated mitochondrial fission and fusion-related protein expression to maintain mitochondrial dynamic balance by activating the PI3K/AKT pathway and increasing AKT phosphorylation, thereby attenuating myocardial I/R injury.

Novel insights into tumorigenesis revealed by molecular analysis of Lynch syndrome cases with multiple colorectal tumors

Background

Lynch syndrome (LS) is an autosomal dominant multi-organ cancer syndrome with a high lifetime risk of cancer. The number of cumulative colorectal adenomas in LS does not generally exceed ten, and removal of adenomas via routine screening minimizes the cancer burden. However, abnormal phenotypes may mislead initial diagnosis and subsequently cause suboptimal treatment.

Aim

Currently, there is no standard guide for the care of multiple colorectal adenomas in LS individuals. We aimed to shed insight into the molecular features and reasons for multiplicity of adenomas in LS patients.

Methods

We applied whole exome sequencing on nine adenomas (ten samples) and three assumed primary carcinomas (five samples) of an LS patient developing the tumors during a 21-year follow-up period. We compared the findings to the tumor profiles of two additional LS cases ascertained through colorectal tumor multiplicity, as well as to ten adenomas and 15 carcinomas from 23 unrelated LS patients with no elevated adenoma burden from the same population. As LS associated cancers can arise via several molecular pathways, we also profiled the tumors for CpG Island Methylator Phenotype (CIMP), and LINE-1 methylation.

Results

All tumors were microsatellite unstable (MSI), and MSI was present in several samples derived from normal mucosa as well. Interestingly, frequent frameshift variants in RNF43 were shared among substantial number of the tumors of our primary case and the tumors of LS cases with multiple tumors but almost absent in our control LS cases. The RNF43 variants were completely absent in the normal tissue, indicating tumor-associated mutational hotspots. The RNF43 status correlated with the mutational signature SBS96. Contrary to LS tumors from the reference set with no elevated colorectal tumor burden, the somatic variants occurred significantly more frequently at C>T in the CpG context, irrespective of CIMP or LINE-1 status, potentially indicating other, yet unknown methylation-related mechanisms. There were no signs of somatic mosaicism affecting the MMR genes. Somatic variants in APC and CTNNB1 were unique to each tumor.

Conclusion

Frequent somatic RNF43 hot spot variants combined with SBS96 signature and increased tendency to DNA methylation may contribute to tumor multiplicity in LS.

Ischemic preconditioning modulates the DNA methylation process of the rat heart to provide tolerance to withstand ischemia reperfusion injury and its associated mitochondrial dysfunction

DNA methylation plays a crucial role in the pathogenesis of myocardial ischemia reperfusion injury(I/R) and the I/R injury can be combated effectively by ischemia preconditioning (IPC), but the role is DNA methylation in this process is unknown. In this study, we uncovered the role of ischemic preconditioning (IPC)- mediated cardioprotection of rat myocardium by using a Langendorff rat heart model with 30 min of ischemia followed by 60 min of reperfusion. Heart conditioned with short cycles of ischemia and reperfusion (IPC procedure) prior to I/R protocol significantly reduced the I/R-induced global DNA hypermethylation level by 32% and the DNMT activity by 33% while rendering cardioprotection. Blocking the PI3K pathway via wortmannin not only negates the cardio-protection by IPC, but also increases the methylation of DNA by 75%. Besides, the correlation analysis showed a negative relationship between PI3K gene expression and the global DNA methylation level (r = - 0.8690, p = 0.0419) in IPC-treated rat hearts. Moreover, the global level DNA hypomethylation induced by IPC exhibited a regulatory effect on the genes involved in I/R pathology mediators like apoptosis (Caspase3), mitochondrial function (PGC 1α, TFAM, ND1) and oxidative stress (CuZnSOD, SOD2), and their corresponding function. The present study results provide novel evidence for the involvement of DNA methylation in the IPC procedure, and suggest DNA methylation as one of the potential therapeutic targets regulated by ischemic preconditioning in rat hearts subjected to ischemia reperfusion.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03965-0.

Increased PI3K pathway activity is associated with recurrent breast cancer in patients with low and intermediate 21-gene recurrence score

AIMS

We investigated key signalling pathways' activity and mutational status of early-stage breast carcinomas with low and intermediate 21-gene recurrence score (RS) to identify molecular features that may predict recurrence.

METHODS

This is a retrospective case-control study of 18 patients with recurrent breast carcinoma with low and intermediate 21-gene RS (<25) and control group of 15 non-recurrent breast cancer patients. DNA and mRNA were extracted from tumour tissue. mRNA expression of genes involved in oestrogen receptor (ER), androgen receptor (AR), PI3K and MAPK signalling pathways was measured by real-time quantitative reverse transcription-qPCR (OncoSIGNal G4 test, InnoSIGN). Tumour mutational landscape was assessed by targeted DNA sequencing (Oncomine Precision Assay).

RESULTS

There were no statistical differences between the groups' demographic and clinicopathological characteristics. PI3K pathway showed significantly higher activity in cases compared with controls (p=0.0014). Receiver operating characteristic curve analysis showed an area under the curve of 0.79 for PI3K pathway activity in the prediction of recurrent disease in low and intermediate 21-gene RS breast cancer. There was no difference in ER, AR and MAPK pathway activity. PIK3CA alterations were the most common driver mutations, but no difference was found between the groups (p=0.46) and no association with PI3K pathway activity (p=0.86). Higher Ki67 gene expression was associated with recurrences (p=0.042) CONCLUSION: Increased PI3K pathway activity, independent of PIK3CA mutations, may play a role in the recurrence of early-stage breast cancer with low and intermediate 21-gene RS. Pathway analysis can help to identify high-risk patients in this setting.

DPY30 knockdown suppresses colorectal carcinoma progression via inducing Raf1/MST2-mediated apoptosis

Colorectal Carcinoma (CRC) is one of the most common malignant tumors of the digestive tract, with a high mortality rate. DPY30 is one of the core subunits of the histone methyltransferase complex, which was involved in many cancer processes. However, the role of DPY30 in the occurrence and progression of CRC remains unclear. In this study, we sought to evaluate the role and mechanism of DPY30 in CRC cells apoptosis. Here, we identified that knockdown of DPY30 significantly inhibited the HT29 and HCT116 cells proliferation in vitro. Moreover, the knockdown of DPY30 significantly increased the apoptosis rate and promoted the expression of apoptosis-related proteins in CRC cells. Meanwhile, DPY30 knockdown promoted CRC cells apoptosis through endogenous programmed death and in a caspase activation-dependent manner. Furthermore, RNA-seq analysis revealed that the action of DPY30 is closely related to the apoptosis biological processes, and screened its potential effectors Raf1. Mechanistically, DPY30 downregulation promotes MST2-induced apoptosis by inhibiting Raf1 transcriptional activity through histone H3 lysine 4 trimethylation (H3K4me3). In vivo experiments showed that DPY30 was correlated with Raf1 in nude mouse subcutaneous xenografts tissues significantly. Clinical colorectal specimens further confirmed that overexpression of DPY30 in malignant tissues was significantly correlated with Raf1 level. The vital role of the DPY30/Raf1/MST2 signaling axis in the cell death and survival rate of CRC cells was disclosed, which provides potential new targets for early diagnosis and clinical treatment of CRC.

Understanding apoptotic induction by Sargentodoxa cuneata-Patrinia villosa herb pair via PI3K/AKT/mTOR signalling in colorectal cancer cells using network pharmacology and cellular studies

ETHNOPHARMACOLOGICAL RELEVANCE

Sargentodoxa cuneata (Sargentodoxa cuneata (Oliv.) Rehder & E.H.Wilson, DXT)-Patrinia villosa(Patrinia villosa (Thunb.) Dufr, BJC) constitutes a commonly employed herb pair in Chinese medicine for colorectal cancer (CRC) treatment. Modern pharmacological investigations have revealed the anticancer activities of both Sargentodoxa cuneata and Patrinia villosa. Nevertheless, comprehensive studies are required to discern the specific antitumor active ingredients and mechanism of action when these two herbs are used in combination.

AIM OF THE STUDY

Through the integration of network pharmacology, molecular docking techniques, experimental assays, and bioinformatics analysis, our study aims to forecast the active ingredients, potential targets, and molecular mechanisms underlying the therapeutic efficacy of this herb pair against CRC.

MATERIALS AND METHODS

Plant names (1, Sargentodoxa cuneata (Oliv.) Rehder & E.H.Wilson; 2, Patrinia villosa (Thunb.) Dufr.) have been verified through WorldFloraOnline (www.worldFloraonline.org) and MPNs (http://mpns.kew.org). The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) were utilized for screening the active ingredients of the herb pair. The PharmMapper database was employed to predict the target proteins for each active ingredient. CRC-related targets were obtained from the Genecards database, Online Mendelian Inheritance in Man (OMIM) database, Disease Gene Network (DisGeNET) database, and Therapeutic Target Database (TTD). Common targets were identified by intersecting the target proteins of all active ingredients with CRC-related targets. Protein-protein interactions (PPI) for the common target proteins were constructed using the String database and Cytoscape 3.9.1 software. Network topology analysis facilitated the identification of core targets. These core targets were subjected to enrichment analysis of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) using the Metascape database. Molecular docking was performed using Discovery Studio 2019 to investigate the interactions between the active ingredients and core target proteins. The core targets were validated through bioinformatics analysis using GEPIA, HPA, and the cBioPortal database. Finally, a series of experiments were conducted to further validate the results in vitro.

RESULT

A total of 15 active ingredients and 255 herb targets were identified, resulting in 66 common targets in conjunction with 6113 disease targets. The PPI analysis highlighted AKT1, EGFR, CASP3, SRC, and ESR1 as core targets. KEGG enrichment analysis indicated significant enrichment in the PI3K-AKT signaling pathway, a pathway associated with cancer. Molecular docking experiments confirmed favorable interactions between dihydroguaiaretic acid and the core target proteins (AKT1, EGFR, CASP3, and ESR1). Bioinformatics analysis revealed differential expression of EGFR and CASP3 in normal and CRC tissues. Cellular experiments further verified that dihydroguaiaretic acid induces apoptosis in colorectal cancer cells through the PI3K-AKT signaling pathway.

CONCLUSION

Our network pharmacology study has elucidated that the Sargentodoxa cuneata-Patrinia villosa herb pair exerts the negative regulation of the PI3K/AKT/mTOR signaling pathway, ultimately leading to the induction of apoptosis in colorectal cancer cells. This research has predicted and validated the active ingredients, potential targets, and molecular mechanisms of Sargentodoxa cuneata-Patrinia villosa in the treatment of CRC, providing scientific evidence for the use of traditional Chinese medicine in managing CRC.

microRNA-944 inhibits breast cancer cell proliferation and promotes cell apoptosis by reducing SPP1 through inactivating the PI3K/Akt pathway

Breast cancer is a common malignancy in women with poor prognosis. This study aimed to investigate the molecular mechanism of microRNA-944 (miR-944) mediated secreted phosphoprotein-1 (SPP1) in breast cancer progression and its regulatory effect on the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Differential gene analysis was performed to identify key genes associated with breast cancer development by screening breast cancer-related microarray data. The expression of miR-944 and SPP1 and their relationship were determined in clinical samples and cells. sh-SPP1, oe-SPP1, LY294002 or miR-944 mimic were transfected into MCF-7 cells to investigate the role of miR-944 mediated SPP1 in breast cancer development and its regulatory effect on the PI3K/Akt pathway. Finally, the tumorigenicity of breast cancer cells was observed in nude mice. Through bioinformatics analysis, we identified SPP1 as a key gene in breast cancer, and miR-944 as an upstream miRNA of SPP1. In breast cancer tissues and cells, the expression of miR-944 was decreased while that of SPP1 was increased. miR-944 negatively regulated the expression of SPP1. In breast cancer cells, SPP1 activated the PI3K/Akt pathway to promote cell proliferation and inhibit apoptosis. In vitro cell experiments showed that the downregulation of miR-944 promoted the high expression of SPP1, which then activated the PI3K/Akt signaling pathway, promoting breast cancer cell proliferation. In vivo experiments further confirmed the anti-cancer role of miR-944 mediated SPP1 in breast cancer. Our study highlights the role of miR-944 mediated SPP1 in inhibiting breast cancer progression by blocking the PI3K/Akt pathway.

Synergistic Inhibitory Effect of Berberine and Low-Temperature Plasma on Non-Small-Cell Lung Cancer Cells via PI3K-AKT-Driven Signaling Axis

Low-temperature plasma (LTP) is an emerging biomedical technique that has been proposed as a potential approach for cancer therapy. Meanwhile, berberine (BER), an active ingredient extracted from various medical herbs, such as Coptischinesis, has been proven antitumor effects in a broad spectrum of cancer cells. In this study, we seek to develop a novel dual cancer therapeutic method by integrating pre-administration of BER and LTP exposure and evaluating its comprehensive antitumor effect on the human non-small-cell lung cancer (NSCLC) cell lines (A549 and H1299) in vitro. Cell viability, cell cycle, cell apoptosis, and intracellular and extracellular ROS were investigated. The results showed that cotreatment of BER and LTP significantly decreased the cell viability, arrested the cell cycle in the S phase, promoted cell apoptosis, and increased intracellular and extracellular ROS. Additionally, RNA Sequencing (RNA-Seq) technology was used to explore potential mechanisms. The differentially expressed genes among different treatment groups of NSCLC cells were analyzed and were mainly enriched in the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. Moreover, cotreatment of BER and LTP notably depressed the total protein expression level of PI3K and AKT with immunoblotting. In conclusion, BER and LTP have a synergistic inhibitory effect on NSCLC cells via the PI3K-AKT signaling pathway, which could provide a promising strategy for supplementary therapy in the anti-NSCLC battle.

Dopamine and cyclic adenosine monophosphate-regulated phosphoprotein with an apparent Mr of 32000 promotes colorectal cancer growth

BACKGROUND

Dopamine and cyclic adenosine monophosphate (cAMP)-regulated phosphoprotein with an apparent Mr of 32000 (DARPP-32) is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain. However, recent studies have shown that DARPP-32 is also expressed in other tissues, including colorectal cancer (CRC), where its function is not well understood.

AIM

To explore the effect of DARPP-32 on CRC progression.

METHODS

The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays. The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2’-deoxyuridine assays, while apoptosis was measured by flow cytometry. The migratory and invasive potential of CRC cell lines were determined using wound healing and transwell chamber assays. In vivo studies involved monitoring the growth rate of xenograft tumors. Finally, the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses.

RESULTS

DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC. Overexpression of DARPP-32 was shown to promote cancer cell proliferation, migration, and invasion and reduce apoptosis. DARPP-32 knockdown resulted in the opposite functional effects. Mechanistically, DARPP-32 may regulate the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway in order to carry out its biological function.

CONCLUSION

DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.

Oncogenic transmembrane protein 158 drives the PI3K/Akt signaling pathway to accelerate gastric cancer cell growth

Gastric cancer (GC) is a serious threat to human health and an important cause of cancer-related death. Herein, we evaluated the influence of transmembrane protein 158 (TMEM158) on GC cell growth. According to Genomic Spatial Event (GSE) and The Cancer Genome Atlas (TCGA) databases, TMEM158 content is amplified in GC tissues. The diagnostic value of TMEM158 expression in GC is huge. GC sufferers with high expression of TMEM158 were associated with poor overall survival. In addition, TMEM158 content was increased in GC cells. TMEM158 promoted GC cell proliferation by modulating the PI3K/Akt signaling pathway. Lack of TMEM158 reduced GC tumor growth. Collectively, TMEM158 accelerated GC cell proliferation by modulating the PI3K/Akt signaling pathway, making it a prospective biomarker for survival in GC patients.

PI3K/AKT/mTOR signaling transduction pathway and targeted therapies in cancer

The PI3K/AKT/mTOR (PAM) signaling pathway is a highly conserved signal transduction network in eukaryotic cells that promotes cell survival, cell growth, and cell cycle progression. Growth factor signalling to transcription factors in the PAM axis is highly regulated by multiple cross-interactions with several other signaling pathways, and dysregulation of signal transduction can predispose to cancer development. The PAM axis is the most frequently activated signaling pathway in human cancer and is often implicated in resistance to anticancer therapies. Dysfunction of components of this pathway such as hyperactivity of PI3K, loss of function of PTEN, and gain-of-function of AKT, are notorious drivers of treatment resistance and disease progression in cancer. In this review we highlight the major dysregulations in the PAM signaling pathway in cancer, and discuss the results of PI3K, AKT and mTOR inhibitors as monotherapy and in co-administation with other antineoplastic agents in clinical trials as a strategy for overcoming treatment resistance. Finally, the major mechanisms of resistance to PAM signaling targeted therapies, including PAM signaling in immunology and immunotherapies are also discussed.

A systematic review of the research progress of traditional Chinese medicine against pulmonary fibrosis: from a pharmacological perspective

Pulmonary fibrosis is a chronic progressive interstitial lung disease caused by a variety of etiologies. The disease can eventually lead to irreversible damage to the lung tissue structure, severely affecting respiratory function and posing a serious threat to human health. Currently, glucocorticoids and immunosuppressants are the main drugs used in the clinical treatment of pulmonary fibrosis, but their efficacy is limited and they can cause serious adverse effects. Traditional Chinese medicines have important research value and potential for clinical application in anti-pulmonary fibrosis. In recent years, more and more scientific researches have been conducted on the use of traditional Chinese medicine to improve or reduce pulmonary fibrosis, and some important breakthroughs have been made. This review paper systematically summarized the research progress of pharmacological mechanism of traditional Chinese medicines and their active compounds in improving or reducing pulmonary fibrosis. We conducted a systematic search in several main scientific databases, including PubMed, Web of Science, and Google Scholar, using keywords such as idiopathic pulmonary fibrosis, pulmonary fibrosis, interstitial pneumonia, natural products, herbal medicine, and therapeutic methods. Ultimately, 252 articles were included and systematically evaluated in this analysis. The anti-fibrotic mechanisms of these traditional Chinese medicine studies can be roughly categorized into 5 main aspects, including inhibition of epithelial-mesenchymal transition, anti-inflammatory and antioxidant effects, improvement of extracellular matrix deposition, mediation of apoptosis and autophagy, and inhibition of endoplasmic reticulum stress. The purpose of this article is to provide pharmaceutical researchers with information on the progress of scientific research on improving or reducing Pulmonary fibrosis with traditional Chinese medicine, and to provide reference for further pharmacological research.

Dimethyladenosine Transferase 1 Homolog Promotes Human Gastric Carcinoma Cell Proliferation and Inhibits Apoptosis via the AKT Pathway

BACKGROUND/AIMS

Our previous work identified the dimethyladenosine transferase 1 homolog as a novel prognostic factor for detecting human gastric carcinoma with high sensitivity and specificity. The high expression of dimethyladenosine transferase 1 is closely associated with the occurrence and progression of gastric carcinoma. However, the underlying mechanism of dimethyladenosine transferase 1 for the occurrence and development of gastric carcinoma is not well elucidated yet.

MATERIALS AND METHODS

In our present study, the biological role of dimethyladenosine transferase 1 on cell proliferation, apoptosis, and cell cycle progression in human gastric carcinoma cells was investigated through in vitro and in vivo assays by the overexpression and knockdown of dimethyladenosine transferase 1 2-way authentication method.

RESULTS

We found that the overexpression of dimethyladenosine transferase 1 significantly promotes cell proliferation (P < .001) and inhibition of cell apoptosis (P < .01) in SGC-7901 cells. However, the in vivo experiment results of the knockdown dimethyladenosine transferase 1 using small interfering RNAs in the MKN-45 are just the opposite. Reverse-transcriptase polymerase chain reaction and western blotting analysis revealed that overexpressed dimethyladenosine transferase 1 in SGC-7901 cells significantly activated the AKT pathway compared to control cells. In contrast, we found that apoptosis genes such as Caspase-3 and Caspase-9 were downregulated in those cells. The xenograft nude mice model exhibited increased tumor growth (P < .01) and weight loss (P < .01), with the overexpression of dimethyladenosine transferase 1 homolog in the SGC-7901 cells. These results have been further confirmed through backward verification in dimethyladenosine transferase 1 knockdown cells.

CONCLUSIONS

Taken together, our results indicated that the dimethyladenosine transferase 1 plays a crucial role in stimulating cancer cell proliferation and contributes to apoptosis resistance in human gastric carcinoma. Meanwhile, it provides a potential therapeutic target for gastric carcinoma treatment and is worthy of further studies.

Proteomic Dynamics of Breast Cancer Cell Lines Identifies Potential Therapeutic Protein Targets

Treatment and relevant targets for breast cancer (BC) remain limited, especially for triple-negative BC (TNBC). We identified 6091 proteins of 76 human BC cell lines using data-independent acquisition (DIA). Integrating our proteomic findings with prior multi-omics datasets, we found that including proteomics data improved drug sensitivity predictions and provided insights into the mechanisms of action. We subsequently profiled the proteomic changes in nine cell lines (five TNBC and four non-TNBC) treated with EGFR/AKT/mTOR inhibitors. In TNBC, metabolism pathways were dysregulated after EGFR/mTOR inhibitor treatment, while RNA modification and cell cycle pathways were affected by AKT inhibitor. This systematic multi-omics and in-depth analysis of the proteome of BC cells can help prioritize potential therapeutic targets and provide insights into adaptive resistance in TNBC.

The Promise of Epigenetics Research in the Treatment of Appendiceal Neoplasms

Appendiceal cancers (AC) are a rare and heterogeneous group of malignancies. Historically, appendiceal neoplasms have been grouped with colorectal cancers (CRC), and treatment strategies have been modeled after CRC management guidelines due to their structural similarities and anatomical proximity. However, the two have marked differences in biological behavior and treatment response, and evidence suggests significant discrepancies in their respective genetic profiles. In addition, while the WHO classification for appendiceal cancers is currently based on traditional histopathological criteria, studies have demonstrated that histomorphology does not correlate with survival or treatment response in AC. Due to their rarity, appendiceal cancers have not been studied as extensively as other gastrointestinal cancers. However, their incidence has been increasing steadily over the past decade, making it crucial to identify new and more effective strategies for detection and treatment. Recent efforts to map and understand the molecular landscape of appendiceal cancers have unearthed a wealth of information that has made it evident that appendiceal cancers possess a unique molecular profile, distinct from other gastrointestinal cancers. This review focuses on the epigenetic landscape of epithelial appendiceal cancers and aims to provide a comprehensive overview of the current state of knowledge of epigenetic changes across different appendiceal cancer subtypes, highlighting the challenges as well as the promise of employing epigenetics in the quest for the detection of biomarkers, therapeutic targets, surveillance markers, and predictors of treatment response and survival in epithelial appendiceal neoplasms.

Detailed molecular and pathological analyses of primary intracranial embryonal rhabdomyosarcoma with a BRAF mutation: illustrative case

BACKGROUND

The etiological significance of the RAS and PI3K pathways has been reported in systemic embryonal rhabdomyosarcoma (ERMS) but not in primary intracranial ERMS (PIERMS). Herein, the authors present a unique case of PIERMS with a BRAF mutation.

OBSERVATIONS

A 12-year-old girl with progressive headache and nausea was diagnosed with a tumor in the right parietal lobe. Semi-emergency surgery revealed an intra-axial lesion that was histopathologically identical to an ERMS. Next-generation sequencing indicated a BRAF mutation as a pathogenic variation, but the RAS and PI3K pathways showed no alteration. Although there is no established reference class for PIERMS, the DNA methylation prediction was closest to that of ERMS, indicating the possibility of PIERMS. The final diagnosis was PIERMS. The patient underwent local radiotherapy (50.4 Gy) and multiagent chemotherapy, with no recurrence for 12 months after surgery.

LESSONS

This may be the first case demonstrating the molecular features of PIERMS, especially the intra-axial type. The results showed a mutation in BRAF but not in the RAS and PI3K pathways, which is different from the existing ERMS features. This molecular difference may cause differences in DNA methylation profiles. Accumulation of the molecular features of PIERMS is necessary before any conclusions can be drawn.

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.

Nintedanib Ameliorates Bleomycin-Induced Pulmonary Fibrosis, Inflammation, Apoptosis, and Oxidative Stress by Modulating PI3K/Akt/mTOR Pathway in Mice

Idiopathic pulmonary fibrosis (IPF) seriously threatens human life and health, and no curative therapy is available at present. Nintedanib is the first agent approved by the US Food and Drug Administration (FDA) in order to treat IPF; however, its mechanism of inhibition of IPF is still elusive. According to recent studies, nintedanib is a potent inhibitor. It can antagonize platelet-derived growth factor (PDGF), basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), etc., to inhibit pulmonary fibrosis. Whether there are other signaling pathways involved in IPF remains unknown. This study focused on investigating the therapeutic efficacy of nintedanib in bleomycin-mediated pulmonary fibrosis (PF) mice through PI3K/Akt/mTOR pathway. Following the induction of pulmonary fibrosis in C57 mice through bleomycin (BLM) administration, the mice were randomized into five groups: (1) the normal control group, (2) the BLM model control group, (3) the low-dose Nintedanib administration model group, (4) the medium-dose nintedanib administration model group, and (5) the high-dose nintedanib administration model group. For lung tissues, morphological changes were found by HE staining and Masson staining, ELISA method was used to detect inflammatory factors, alkaline water method to estimate collagen content, and western blotting for protein levels. TUNEL staining and immunofluorescence methods were used to analyze the effect of nintedanib on lung tissue and the impacts and underlying mechanisms of bleomycin-induced pulmonary fibrosis. After 28 days, bleomycin-treated mice developed significant pulmonary fibrosis. Relative to bleomycin-treated mice, nintedanib-treated mice had markedly reduced degrees of PF. In addition, nintedanib showed lung-protective effects by up-regulating antioxidant levels, down-regulating inflammatory protein expression, and reducing collagen accumulation. We demonstrated that nintedanib ameliorated bleomycin-induced lung injury by inhibiting the P13K/Akt/mTOR pathway as well as apoptosis. In addition, significant improvement in pulmonary fibrosis was seen after nintedanib (30/60/120 mg/kg body weight/day) treatment through a dose-dependent way. Histopathological results further corroborated the effect of nintedanib treatment on remarkably attenuating bleomycin-mediated mouse lung injury. According to our findings, nintedanib restores the antioxidant system, suppresses pro-inflammatory factors, and inhibits apoptosis. Nintedanib can reduce bleomycin-induced inflammation by downregulating PI3K/Akt/mTOR pathway, PF, and oxidative stress (OS).

Principles of phosphoproteomics and applications in cancer research

Phosphorylation constitutes the most common and best-studied regulatory post-translational modification in biological systems and archetypal signalling pathways driven by protein and lipid kinases are disrupted in essentially all cancer types. Thus, the study of the phosphoproteome stands to provide unique biological information on signalling pathway activity and on kinase network circuitry that is not captured by genetic or transcriptomic technologies. Here, we discuss the methods and tools used in phosphoproteomics and highlight how this technique has been used, and can be used in the future, for cancer research. Challenges still exist in mass spectrometry phosphoproteomics and in the software required to provide biological information from these datasets. Nevertheless, improvements in mass spectrometers with enhanced scan rates, separation capabilities and sensitivity, in biochemical methods for sample preparation and in computational pipelines are enabling an increasingly deep analysis of the phosphoproteome, where previous bottlenecks in data acquisition, processing and interpretation are being relieved. These powerful hardware and algorithmic innovations are not only providing exciting new mechanistic insights into tumour biology, from where new drug targets may be derived, but are also leading to the discovery of phosphoproteins as mediators of drug sensitivity and resistance and as classifiers of disease subtypes. These studies are, therefore, uncovering phosphoproteins as a new generation of disruptive biomarkers to improve personalised anti-cancer therapies.

CDK9 inhibition induces epigenetic reprogramming revealing strategies to circumvent resistance in lymphoma

Diffuse large B-cell lymphoma (DLBCL) exhibits significant genetic heterogeneity which contributes to drug resistance, necessitating development of novel therapeutic approaches. Pharmacological inhibitors of cyclin-dependent kinases (CDK) demonstrated pre-clinical activity in DLBCL, however many stalled in clinical development. Here we show that AZD4573, a selective inhibitor of CDK9, restricted growth of DLBCL cells. CDK9 inhibition (CDK9i) resulted in rapid changes in the transcriptome and proteome, with downmodulation of multiple oncoproteins (eg, MYC, Mcl-1, JunB, PIM3) and deregulation of phosphoinotiside-3 kinase (PI3K) and senescence pathways. Following initial transcriptional repression due to RNAPII pausing, we observed transcriptional recovery of several oncogenes, including MYC and PIM3. ATAC-Seq and ChIP-Seq experiments revealed that CDK9i induced epigenetic remodeling with bi-directional changes in chromatin accessibility, suppressed promoter activation and led to sustained reprograming of the super-enhancer landscape. A CRISPR library screen suggested that SE-associated genes in the Mediator complex, as well as AKT1, confer resistance to CDK9i. Consistent with this, sgRNA-mediated knockout of MED12 sensitized cells to CDK9i. Informed by our mechanistic findings, we combined AZD4573 with either PIM kinase or PI3K inhibitors. Both combinations decreased proliferation and induced apoptosis in DLBCL and primary lymphoma cells in vitro as well as resulted in delayed tumor progression and extended survival of mice xenografted with DLBCL in vivo. Thus, CDK9i induces reprogramming of the epigenetic landscape, and super-enhancer driven recovery of select oncogenes may contribute to resistance to CDK9i. PIM and PI3K represent potential targets to circumvent resistance to CDK9i in the heterogeneous landscape of DLBCL.

A Systematic Review of Progress toward Unlocking the Power of Epigenetics in NSCLC: Latest Updates and Perspectives

Epigenetic research has the potential to improve our understanding of the pathogenesis of cancer, specifically non-small-cell lung cancer, and support our efforts to personalize the management of the disease. Epigenetic alterations are expected to have relevance for early detection, diagnosis, outcome prediction, and tumor response to therapy. Additionally, epi-drugs as therapeutic modalities may lead to the recovery of genes delaying tumor growth, thus increasing survival rates, and may be effective against tumors without druggable mutations. Epigenetic changes involve DNA methylation, histone modifications, and the activity of non-coding RNAs, causing gene expression changes and their mutual interactions. This systematic review, based on 110 studies, gives a comprehensive overview of new perspectives on diagnostic (28 studies) and prognostic (25 studies) epigenetic biomarkers, as well as epigenetic treatment options (57 studies) for non-small-cell lung cancer. This paper outlines the crosstalk between epigenetic and genetic factors as well as elucidates clinical contexts including epigenetic treatments, such as dietary supplements and food additives, which serve as anti-carcinogenic compounds and regulators of cellular epigenetics and which are used to reduce toxicity. Furthermore, a future-oriented exploration of epigenetic studies in NSCLC is presented. The findings suggest that additional studies are necessary to comprehend the mechanisms of epigenetic changes and investigate biomarkers, response rates, and tailored combinations of treatments. In the future, epigenetics could have the potential to become an integral part of diagnostics, prognostics, and personalized treatment in NSCLC.

Binding and selectivity studies of phosphatidylinositol 3-kinase (PI3K) inhibitors

Overexpression of the Phosphatidylinositol 3-kinase (PI3K) proteins have been observed in cancer cells. Targeting the phosphatidylinositol 3-kinase (PI3K) signaling transduction pathway by inhibition of the PI3K substrate recognition sites has been proved to be an effective approach to block cancer progression. Many PI3K inhibitors have been developed. Seven drugs have been approved by the US FDA with a mechanism of targeting the phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway. In this study, we used docking tools to investigate selective binding of ligands toward four different subtypes of PI3Ks (PI3Kα, PI3Kβ, PI3Kγ and PI3Kδ). The affinity predicted from both the Glide dock and the Movable-Type (MT)-based free energy calculations agreed well with the experimental data. The validation of our predicted methods with a large dataset of 147 ligands showed very small mean errors. We identified residues that may dictate the subtype-specific binding. Particularly, residues Asp964, Ser806, Lys890 and Thr886 of PI3Kγ might be utilized for PI3Kγ-selective inhibitor design. Residues Val828, Trp760, Glu826 and Tyr813 may be important for PI3Kδ-selective inhibitor binding.

Downregulation of PI3K/AKT/mTOR Pathway in Juglone-Treated Bovine Oocytes

We have previously reported that juglone, a natural compound found in Juglandaceae with a wide range of biological activities, can reduces the developmental competence of bovine oocytes. In the current study, we investigated the possible mechanisms behind the toxicity of juglone and the relationship with PI3K/AKT/mTOR signaling during the in vitro maturation (IVM) of oocytes. Results show that oocyte exposure to juglone was associated with a significant decrease in filamentous actin (F-actin) accumulation. The RT-qPCR showed downregulation of the meiosis progression indicator GSK-3A, oocyte development marker BMP15, mitochondria fusion controlling MFN1, oxidative stress-related OGG1, and histone methylation-related EZH1, EZH2, SUZ12, G9a, and SUV39H2 genes in juglone-treated oocytes. In addition, glycolysis- (PFK1 and GLUT1), ATP synthesis- (ATPase8 and ATP5F1B), and OXPHOS-specific markers (SDHA and SDHD), as well as the oocyte survival regulators (SOD2, VEGF, and MAPK1) significantly decreased upon juglone treatment. Moreover, lower expression of PI3K, AKT, and mTOR was observed at the transcriptional and/or translational level(s). The autophagy markers LC3B and beclin-1 as well as the DNA damage-specific marker 8-OxoG displayed overexpression in juglone-exposed oocytes. Taken together, our results show that administration of juglone during the IVM can reduce the quality and developmental health of bovine oocytes through downregulation of the PI3K/AKT/mTOR pathway and its downstream signaling cascades.

A Phase 1B open-label study of gedatolisib (PF-05212384) in combination with other anti-tumour agents for patients with advanced solid tumours and triple-negative breast cancer

BACKGROUND

This Phase 1b study (B2151002) evaluated the PI3K/mTOR inhibitor gedatolisib (PF-05212384) in combination with other anti-tumour agents in advanced solid tumours.

METHODS

Patients with various malignancies were administered gedatolisib (90‒310 mg intravenously every week [QW]) plus docetaxel (arm A) or cisplatin (arm B) (each 75 mg/m2 intravenously Q3W) or dacomitinib (30 or 45 mg/day orally). The safety and tolerability of combination therapies were assessed during dose escalation; objective response (OR) and safety were assessed during dose expansion.

RESULTS

Of 110 patients enrolled, 107 received gedatolisib combination treatment. Seven of 70 (10.0%) evaluable patients had dose-limiting toxicities; the most common was grade 3 oral mucositis (n = 3). Based upon reprioritisation of the sponsor's portfolio, dose expansion focused on arm B, gedatolisib (180 mg QW) plus cisplatin in patients (N = 22) with triple-negative breast cancer (TNBC). OR (95% CI) was achieved in four of ten patients in first-line (overall response rate 40.0% [12.2-73.8%]) and four of 12 in second/third-line (33.3% [9.9-65.1%]) settings. One patient in each TNBC arm (10%, first-line; 8.3%, second/third-line) achieved a complete response.

CONCLUSIONS

Gedatolisib combination therapy showed an acceptable tolerability profile, with clinical activity at the recommended Phase 2 dose in patients with TNBC.

CLINICAL TRIAL

ClinicalTrial.gov: NCT01920061.

Silencing of KNTC1 inhibits hepatocellular carcinoma cells progression via suppressing PI3K/Akt pathway

Kinetochore associated 1 (KNTC1) encodes a kinetochore component in Rod-Zwilch-ZW10 (RZZ) complex which is essential for the segregation of sister chromatids during mitosis and participates in the spindle checkpoint. Recent research demonstrated that kinetochore proteins may be potential biomarkers and may contribute to the development of human malignancies. Our immunohistochemistry experiment showed that KNTC1 was highly expressed in hepatocellular carcinoma (HCC) tissues and correlated with terrible prognosis, indicating that KNTC1 acts a pivotal role in HCC development. Furthermore, lentivirus delivered short hairpin RNA (shRNA) KNTC1 (Lv-shKNTC1) was applied to infect BEL-7404 and SK-HEP-1 to identify roles of KNTC1 on HCC. Lv-shKNTC1 cells showed reduced proliferation ability, increased apoptosis and decreased migration ability. In vivo experiments suggested that xenografts grow significantly slower upon the silencing of KNTC1. Mechanistically, the protein levels of PIK3CA, p-Akt, CCND1, CDK6 are all down-regulated in Lv-KNTC1 cells and the Lv-shKNTC1 tumor tissues of nude mice. Therefore, KNTC1 may affect the biological activity of HCC cells through PI3K/Akt signaling pathway. Further studies revealed that ZW10 is a pivotal protein that participates in KNTC1-induced regulation of PI3K/Akt signaling pathway. In summary, the key finding of this report highlighted the significance of KNTC1 in tumor regression of HCC, demonstrating KNTC1 as an innovative target for adjuvant treatment of HCC.

DPY30 promotes the growth and survival of osteosarcoma cell by regulating the PI3K/AKT signal pathway

Osteosarcoma (OS) is characterized by aggressive features including invasiveness and high incidence of metastasis. OS patients with metastases are difficult to treat and suffer from a poor prognosis. DPY30 (protein dpy-30 homolog) is a key component of SET1/MLL family of H3K4 methyltransferases, which is implicated in the progression of multiple cancers. However, the potential functional engagement of DPY30 in OS remains to be unveiled. The objective of this study is to investigate the potential roles of DPY30 in the regulation of malignant phenotypes of OS cells. We examined DPY30 expression from a published dataset (GSE28424) as well as in OS tissues and adjacent normal tissues from OS patients. The association of DPY30 expression level and clinicopathologic parameters was assessed by Chi-square test. The role of DPY30 in regulating the malignant phenotype of OS cells and tumorigenesis was examined by in vitro functional assays and xenograft mouse model. We reported an upregulation of DPY30 in OS tumor tissues in both published dataset and clinical samples. A high level of DPY30 expression was associated with larger tumor size and more metastasis in OS patients, as well as poor overall survival. DPY30 knockdown in OS cells significantly impairs proliferation, migration and invasion, but induced cellular apoptosis. We further demonstrated that the agonist of PI3K/AKT pathway can rescue the inhibitory effects of DPY30 knockdown in OS cells. Together, our data indicate that DPY30 functions as an oncogene to promote the malignancy of OS cells possibly through PI3K/AKT pathway. The dependency of OS cells on DPY30 overexpression is a targetable vulnerability in OS cells.

The Ginsenoside Compound K Suppresses Stem-Cell-like Properties and Colorectal Cancer Metastasis by Targeting Hypoxia-Driven Nur77-Akt Feed-Forward Signaling

Hypoxia reprograms cancer stem cells. Nur77, an orphan nuclear receptor, highly expresses and facilitates colorectal cancer (CRC) stemness and metastasis under a hypoxic microenvironment. However, safe and effective small molecules that target Nur77 for CSC depletion remain unexplored. Here, we report our identification of the ginsenoside compound K (CK) as a new ligand of Nur77. CK strongly inhibits hypoxia-induced CRC sphere formation and CSC phenotypes in a Nur77-dependent manner. Hypoxia induces an intriguing Nur77-Akt feed-forward loop, resulting in reinforced PI3K/Akt signaling that is druggable by targeting Nur77. CK directly binds and modulates Nur77 phosphorylation to block the Nur77-Akt activation loop by disassociating Nur77 from the p63-bound Dicer promoter. The transcription of Dicer that is silenced under a hypoxia microenvironment is thus reactivated by CK. Consequently, the expression and processing capability of microRNA let-7i-5p are significantly increased, which targets PIK3CA mRNA for decay. The in vivo results showed that CK suppresses cancer stemness and metastasis without causing significant adverse effects. Given that the majority of FDA-approved and currently clinically tested PI3K/Akt inhibitors are reversible ATP-competitive kinase antagonists, targeting Nur77 for PI3K/Akt inactivation may provide an alternative strategy to overcoming concerns about drug selectivity and safety. The mechanistic target identification provides a basis for exploring CK as a promising nutraceutical against CRC.

Early Mechanisms of Chemoresistance in Retinoblastoma

Retinoblastoma is the most common eye cancer in children and is fatal if left untreated. Over the past three decades, chemotherapy has become the mainstay of eye-sparing treatment. Nevertheless, chemoresistance continues to represent a major challenge leading to ocular and systemic toxicity, vision loss, and treatment failure. Unfortunately, the mechanisms leading to chemoresistance remain incompletely understood. Here, we engineered low-passage human retinoblastoma cells to study the early molecular mechanisms leading to resistance to carboplatin, one of the most widely used agents for treating retinoblastoma. Using single-cell next-generation RNA sequencing (scRNA-seq) and single-cell barcoding technologies, we found that carboplatin induced rapid transcriptomic reprogramming associated with the upregulation of PI3K-AKT pathway targets, including ABC transporters and metabolic regulators. Several of these targets are amenable to pharmacologic inhibition, which may reduce the emergence of chemoresistance. We provide evidence to support this hypothesis using a third-generation inhibitor of the ABCB1 transporter.

Akt: a key transducer in cancer

Growth factor signaling plays a pivotal role in diverse biological functions, such as cell growth, apoptosis, senescence, and migration and its deregulation has been linked to various human diseases. Akt kinase is a central player transmitting extracellular clues to various cellular compartments, in turn executing these biological processes. Since the discovery of Akt three decades ago, the tremendous progress towards identifying its upstream regulators and downstream effectors and its roles in cancer has been made, offering novel paradigms and therapeutic strategies for targeting human diseases and cancers with deregulated Akt activation. Unraveling the molecular mechanisms for Akt signaling networks paves the way for developing selective inhibitors targeting Akt and its signaling regulation for the management of human diseases including cancer.

CDC42 governs normal oviduct multiciliogenesis through activating AKT to ensure timely embryo transport

Ciliated and secretory cells are two major cell types that comprise the oviduct epithelia. Accumulating evidences support a role of oviductal multiciliated epithelia for embryo transport, however the mechanisms underlying this specialized cell type differentiation remain elusive. Here, we report that CDC42 depletion in oviduct epithelia hampers the morphogenesis of multiciliated cell, and results in embryo retention, leading to early pregnancy failure. Utilizing the oviduct organoid model, we further observed that CDC42 guides secretory cells transition into multiciliated cells independent of its GTPase activity and the well-known Notch pathway. Further exploration uncovered the AKT as a novel indispensable regulator for multiciliated cells differentiation, whose activity was maintained by CDC42 through interacting with the p110β. Consistently, re-activating AKT partially incites multiciliated cells differentiation in Cdc42 knockout oviductal organoids. Finally, low levels of CDC42 and phospho-AKT with reduced multiciliated cells in the oviduct are observed in women with ectopic pregnancy. Collectively, we provide previously unappreciated evidence that CDC42-AKT signaling is a critical determinant for morphogenesis of oviduct multiciliated cell, which possesses the clinical application in understanding the pathology of ectopic pregnancy and facilitating the development of prevention strategies.

Mechanisms of cancer cell death induction by paclitaxel: an updated review

Chemoresistance of cancer cells is a major problem in treating cancer. Knowledge of how cancer cells may die or resist cancer drugs is critical to providing certain strategies to overcome tumour resistance to treatment. Paclitaxel is known as a chemotherapy drug that can suppress the proliferation of cancer cells by inducing cell cycle arrest and induction of mitotic catastrophe. However, today, it is well known that paclitaxel can induce multiple kinds of cell death in cancers. Besides the induction of mitotic catastrophe that occurs during mitosis, paclitaxel has been shown to induce the expression of several pro-apoptosis mediators. It also can modulate the activity of anti-apoptosis mediators. However, certain cell-killing mechanisms such as senescence and autophagy can increase resistance to paclitaxel. This review focuses on the mechanisms of cell death, including apoptosis, mitotic catastrophe, senescence, autophagic cell death, pyroptosis, etc., following paclitaxel treatment. In addition, mechanisms of resistance to cell death due to exposure to paclitaxel and the use of combinations to overcome drug resistance will be discussed.

Decrypting a path based approach for identifying the interplay between PI3K and GSK3 signaling cascade from the perspective of cancer

Cancer is one of those leading diseases worldwide, which takes millions of lives every year. Researchers are continuously looking for specific approaches to eradicate the deadly disease, ensuring minimal adverse effects along with more therapeutic significance. Targeting of different aberrantly regulated signaling pathways, involved in cancer, is surely one of the revolutionary chemotherapeutic approach. In this instance, GSK3 and PI3K signaling cascades are considered as important role player for both the oncogenic activation and inactivation which further leads to cancer proliferation and metastasis. In this review, we have discussed the potential role of GSK3 and PI3K signaling in cancer, and we further established the crosstalk between PI3K and GSK3 signaling, through showcasing their cross activation, cross inhibition and convergence pathways in association with cancer. We also exhibited the effect of GSK3 on the efficacy of PI3K inhibitors to overcome the drug resistance and preventing the cell proliferation, metastasis in a combinatorial way with GSK3 inhibitors for a better treatment strategy in clinical settings.

Weighted Gene Co-Expression Network Analysis Identifies Key Modules and Central Genes Associated With Bovine Subcutaneous Adipose Tissue

Background

Fat deposition is an important economic trait in livestock and poultry production. However, the relationship between various genes and signal pathways of fat deposition is still unclear to a large extent. The purpose of this study is to analyze the potential molecular targets and related molecular pathways in bovine subcutaneous adipose tissue.

Results

We downloaded the GSE116775 microarray dataset from Gene Expression Omnibus (GEO). The weighted gene co-expression network (WGCNA) was used to analyze the gene expression profile, and the key gene modules with the highest correlation with subcutaneous adipose tissue were identified, and the functional enrichment of the key modules was analyzed. Then, the “real” Hub gene was screened by in-module analysis and protein–protein interaction network (PPI), and its expression level in tissue samples and adipocytes was verified. The study showed that a total of nine co-expression modules were identified, and the number of genes in these modules ranged from 101 to 1,509. Among them, the blue module is most closely related to subcutaneous adipose tissue, containing 1,387 genes. These genes were significantly enriched in 10 gene ontologies including extracellular matrix organization, biological adhesion, and collagen metabolic process, and were mainly involved in pathways including ECM-receptor interaction, focal adhesion, cAMP signaling pathway, PI3K-AKT signaling pathway, and regulation of lipolysis in adipocytes. In the PPI network and coexpression network, five genes (CAV1, ITGA5, COL5A1, ABL1, and HSPG2) were identified as “real” Hub genes. Analysis of Hub gene expression by dataset revealed that the expression of these Hub genes was significantly higher in subcutaneous adipose tissue than in other tissues. In addition, real-time fluorescence quantitative PCR (qRT-PCR) analysis based on tissue samples and adipocytes also confirmed the above results.

Conclusion

In this study, five key genes related to subcutaneous adipose tissue were discovered, which laid a foundation for further study of the molecular regulation mechanism of subcutaneous adipose tissue development and adipose deposition.

Salvianolic Acid B Alleviates Limb Ischemia in Mice via Promoting SIRT1/PI3K/AKT Pathway-Mediated M2 Macrophage Polarization

Salvianolic acid B (Sal B) is an effective treatment agent for ischemic disease in China. However, Sal B's effects on peripheral arterial disease (PAD) and its mechanism remains poorly understood. Macrophage polarization plays a crucial role in PAD. Nevertheless, treatment modalities that increase the population of anti-inflammatory (M2) macrophages are limited. This study aimed to explore the protective effects of Sal B on limb perfusion and investigate the mechanism of Sal B-induced macrophage polarization. C57BL/6 male mice (6 weeks) were randomized into control, Model + NS, and Model + Sal B groups (n = 5). Then, we established a hind limb ischemia mouse model to assess the Sal B's role (15 mg/kg/d) in PAD. We quantified the blood perfusion via laser speckle contrast imaging (LSCI) and measured the capillary density and muscle edema with CD31 and H&E staining. The Sal B-induced macrophage polarization was confirmed by qPCR and ELISA. The results showed that the Sal B group exhibited a significant improvement in the blood perfusion, capillary density, muscle edema, and M2 markers gene expressions. Cell migration and tube formation were promoted in the endothelial cells stimulated with a culture supernatant from Sal B-treated macrophages. In contrast, endothelial functions improved by Sal B-treated macrophages were impaired in groups treated with SIRT1 and PI3K inhibitors. These findings provide evidence for Sal B's protective role in PAD and demonstrate the enhancement of macrophage polarization via the SIRT1/PI3K/AKT pathway.

miR-29a-3p mitigates the development of osteosarcoma through modulating IGF1 mediated PI3k/Akt/FOXO3 pathway by activating autophagy

Osteosarcoma (OS), occurring in mesenchymal tissues and with a high degree of malignancy, is most common in children and adolescents. At present, we intend to figure out the expression and functions of miR-29a-3p in OS development. Reverse transcription-polymerase chain reaction (RT-PCR) was adopted to monitor the expression of miR-29a-3p and IGF1 in OS tissues and adjacent non-tumor tissues. Then, the 3- (4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay, colony formation experiment, western blot and Transwell assay were conducted to validate OS cell proliferation, colony formation ability, apoptosis, migration and invasion. Next, the association between miR-29a-3p and IGF1 was corroborated by the dual-luciferase reporter assay and the Pearson correlation analysis. Finally, WB was implemented to test the levels of autophagy-related proteins LC3-I/LC3-II, Beclin-1, p62, and the IGF-1R/PI3k/Akt/FOXO3 axis in OS cells. As a result, miR-29a-3p was down-regulated in OS tissues (versus adjacent non-tumor tissues) and OS cell lines. Overexpressing miR-29a-3p aggravated apoptosis, dampened cell proliferation, colony formation, migration and invasion, and promoted autophagy of OS cells. IGF1 was identified as a target of miR-29a-3p. IGF1 induced oncogenic effects in OS by activating IGF-1R/ PI3k/Akt pathway, and it dampened the tumor-suppressive effect of miR-29a-3p on OS. Taken together, miR-29a-3p repressed the OS evolvement through inducing autophagy and inhibiting IGF1 mediated PI3k/Akt/FOXO3 pathway.

Senegenin Inhibits Aβ1-42-Induced PC12 Cells Apoptosis and Oxidative Stress via Activation of the PI3K/Akt Signaling Pathway

BACKGROUND/AIM

Apoptosis and oxidative stress have been considered as key events in the pathogenesis of Alzheimer's disease (AD). Senegenin (Sen), the major and most effective ingredient of Radix Polygalae, which has anti-apoptotic and anti-oxidative effects. The aim of this study was to investigate the anti-apoptotic and anti-oxidant effects of Sen on Aβ_1-42-induced PC12 cells apoptosis and oxidative stress as well as its possible signaling pathway.

METHODS

Rat pheochromocytoma (PC12) cells were treated by 20 μM Aβ_1-42 and then divided into 5 different treatment groups (Control; Aβ_1-42 20 μM; Aβ_1-42 20 μM + Sen 10 μM; Aβ_1-42 20 μM + Sen 30 μM; Aβ_1-42 20μM + Sen 60 μM). PC12 cells activity was detected by MTT assay. Colony formation assay was performed to assess the clonogenic ability of cells. The cell apoptosis was detected by Annexin-V/PI staining. The pro-apoptotic protein (Bax), anti-apoptotic protein (Bcl-2), anti-oxidative stress factor (HO-1, Nuclear Nrf2, Total Nrf2) and pathway-related protein (Akt, P-Akt, PI3K, P-PI3K) were tested by Western blot. The reactive oxygen species (ROS) level was assessed with a DCFH-DA probe.

RESULTS

The results indicated that Sen dose-dependently increased cell viability and reduced the number of apoptotic cells. The ratio of P-PI3K/PI3K and P-Akt/Akt increased in a dose-dependent manner under the treatment of Sen, suggesting that Sen might activate the PI3K/Akt signaling pathway. Moreover, Sen upregulates the ratio of Bcl-2/Bax. Further study revealed that Sen can play an antioxidant role in enhancing HO-1, promoting Nrf2 nuclear translocation and reducing ROS accumulation to reduce oxidative stress.

CONCLUSION

Sen is effective in inhibiting apoptosis and oxidative stress in Aβ_1-42-induced PC12 cells, which likely contribute to the development of novel therapies for AD.

PI3K/AKT/p53 pathway inhibits infectious spleen and kidney necrosis virus infection by regulating autophagy and immune responses

The PI3K/AKT/p53 signaling pathway is activated by various types of cellular stimuli or pathogenic infection, and then regulates fundamental cellular functions to combat these stimulations. Here, we studied the meaningful roles of PI3K/AKT/p53 in regulating cellular machine such as autophagy, immune responses, as well as antiviral activity in Chinese perch brain (CPB) cells infected by infectious spleen and kidney necrosis virus (ISKNV), which is an agent caused devastating losses in mandarin fish (Siniperca chuatsi) industry. We found that ISKNV infection induced up-regulation of host PI3K/AKT/p53 axis, but inhibited autophagy in CPB cells. Interestingly, activation of PI3K/AKT/p53 axis factors trough agonists or overexpression dramatically decreased host autophagy level, inhibited ISKNV replication, and elevated the expression of immune-related genes in CPB cells. In contrast, suppression of PI3K/AKT/p53 pathway by inhibitors or small interfering RNA (siRNA)-mediated gene silence increased the autophagy and ISKNV replication, but down-regulated immune responses in CPB cells. All these results indicate that PI3K/AKT/p53 pathway plays an important role in anti-ISKNV infection and can be used as a new target for controlling ISKNV disease.

Targeting PI3K/AKT signaling for treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive fibrotic interstitial pneumonia with unknown causes. The incidence rate increases year by year and the prognosis is poor without cure. Recently, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/AKT) signaling pathway can be considered as a master regulator for IPF. The contribution of the PI3K/AKT in fibrotic processes is increasingly prominent, with PI3K/AKT inhibitors currently under clinical evaluation in IPF. Therefore, PI3K/AKT represents a critical signaling node during fibrogenesis with potential implications for the development of novel anti-fibrotic strategies. This review epitomizes the progress that is being made in understanding the complex interpretation of the cause of IPF, and demonstrates that PI3K/AKT can directly participate to the greatest extent in the formation of IPF or cooperate with other pathways to promote the development of fibrosis. We further summarize promising PI3K/AKT inhibitors with IPF treatment benefits, including inhibitors in clinical trials and pre-clinical studies and natural products, and discuss how these inhibitors mitigate fibrotic progression to explore possible potential agents, which will help to develop effective treatment strategies for IPF in the near future.

DNA Methylation of PI3K/AKT Pathway-Related Genes Predicts Outcome in Patients with Pancreatic Cancer: A Comprehensive Bioinformatics-Based Study

Simple Summary

Pancreatic cancer is a highly lethal malignancy. Dysregulation of epigenetic mechanisms leads to abnormal patterns of gene expression contributing to the development and progression of cancer. We explored the ability of DNA methylation of PI3K-related genes to differentiate between malignant and healthy pancreatic tissue using distinct pancreatic cancer cohorts, and found that the methylation levels of the ITGA4, SFN, ITGA2, and PIK3R1 genes are altered in tumour samples since the early stages of malignant transformation and could serve as new diagnostic tools. We also demonstrate that these alterations correlate with overall survival and recurrence-free survival of the patients suggesting that its assessment can serve as independent prognostic indicators of patients’ survival with higher sensitivity and specificity than the currently implemented biomarkers. Therefore, the methylation profile of genes involved in this pathway may be an alternative method for predicting cell malignancy and help doctors’ decisions on patient care.

Abstract

Pancreatic cancer (PCA) is one of the most lethal malignancies worldwide with a 5-year survival rate of 9%. Despite the advances in the field, the need for an earlier detection and effective therapies is paramount. PCA high heterogeneity suggests that epigenetic alterations play a key role in tumour development. However, only few epigenetic biomarkers or therapeutic targets have been identified so far. Here we explored the potential of distinct DNA methylation signatures as biomarkers for early detection and prognosis of PCA. PI3K/AKT-related genes differentially expressed in PCA were identified using the Pancreatic Expression Database (n = 153). Methylation data from PCA patients was obtained from The Cancer Genome Atlas (n = 183), crossed with clinical data to evaluate the biomarker potential of the epigenetic signatures identified and validated in independent cohorts. The majority of selected genes presented higher expression and hypomethylation in tumour tissue. The methylation signatures of specific genes in the PI3K/AKT pathway could distinguish normal from malignant tissue at initial disease stages with AUC > 0.8, revealing their potential as PCA diagnostic tools. ITGA4, SFN, ITGA2, and PIK3R1 methylation levels could be independent prognostic indicators of patients’ survival. Methylation status of SFN and PIK3R1 were also associated with disease recurrence. Our study reveals that the methylation levels of PIK3/AKT genes involved in PCA could be used to diagnose and predict patients’ clinical outcome with high sensitivity and specificity. These results provide new evidence of the potential of epigenetic alterations as biomarkers for disease screening and management and highlight possible therapeutic targets.

Promoting axon regeneration in the central nervous system by increasing PI3-kinase signaling

Much research has focused on the PI3-kinase and PTEN signaling pathway with the aim to stimulate repair of the injured central nervous system. Axons in the central nervous system fail to regenerate, meaning that injuries or diseases that cause loss of axonal connectivity have life-changing consequences. In 2008, genetic deletion of PTEN was identified as a means of stimulating robust regeneration in the optic nerve. PTEN is a phosphatase that opposes the actions of PI3-kinase, a family of enzymes that function to generate the membrane phospholipid PIP₃ from PIP₂ (phosphatidylinositol (3,4,5)-trisphosphate from phosphatidylinositol (4,5)-bisphosphate). Deletion of PTEN therefore allows elevated signaling downstream of PI3-kinase, and was initially demonstrated to promote axon regeneration by signaling through mTOR. More recently, additional mechanisms have been identified that contribute to the neuron-intrinsic control of regenerative ability. This review describes neuronal signaling pathways downstream of PI3-kinase and PIP₃, and considers them in relation to both developmental and regenerative axon growth. We briefly discuss the key neuron-intrinsic mechanisms that govern regenerative ability, and describe how these are affected by signaling through PI3-kinase. We highlight the recent finding of a developmental decline in the generation of PIP₃ as a key reason for regenerative failure, and summarize the studies that target an increase in signaling downstream of PI3-kinase to facilitate regeneration in the adult central nervous system. Finally, we discuss obstacles that remain to be overcome in order to generate a robust strategy for repairing the injured central nervous system through manipulation of PI3-kinase signaling.

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone-Induced Histone Acetylation via α7nAChR-Mediated PI3K/Akt Activation and Its Impact on γ-H2AX Generation

A typical tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is known as a strong carcinogen. We previously reported that metabolized NNK induced histone H2AX phosphorylation (γ-H2AX), a DNA damage-induced histone modification. In this study, we found that NNK globally acetylated histone H3, which affected γ-H2AX generation. Human lung adenocarcinoma A549 was treated with several doses of NNK. NNK induced dose-dependent global histone H3 acetylation (Ac-H3), at 2 to 12 h after the treatment, independent of the cell cycle. The Ac-H3 pattern was not affected by CYP2A13 overexpression unlike γ-H2AX, indicating no requirement of NNK metabolism to induce Ac-H3. Immunofluorescence staining of Ac-H3 was uniform throughout the nucleus, whereas γ-H2AX was formed as foci and did not coincide with Ac-H3. Nicotinic receptor antagonist methyllycaconitine inhibited Ac-H3 and also γ-H2AX. Phosphoinositide-3-kinase (PI3K)/Akt inhibitors, LY294002, wortmannin, and GSK690693, also suppressed both Ac-H3 and γ-H2AX, whereas KU-55933, an inhibitor of ataxia telangiectasia mutated (ATM) upstream of γ-H2AX, inhibited γ-H2AX but not Ac-H3. These results suggested that binding of NNK to the nicotinic acetylcholine receptor (α7nAChR) activated the PI3K/Akt pathway, resulting in Ac-H3. The activated pathway leading to Ac-H3 enhanced γ-H2AX, suggesting that NNK-induced DNA damage is impacted by the α7nAChR-mediated signal transduction pathway.

Impact of Stilbenes as Epigenetic Modulators of Breast Cancer Risk and Associated Biomarkers

With the recent advancement of genetic screening for testing susceptibility to mammary oncogenesis in women, the relevance of the gene−environment interaction has become progressively apparent in the context of aberrant gene expressions. Fetal exposure to external stressors, hormones, and nutrients, along with the inherited genome, impact its traits, including cancer susceptibility. Currently, there is increasing interest in the role of epigenetic biomarkers such as genomic methylation signatures, plasma microRNAs, and alterations in cell-signaling pathways in the diagnosis and primary prevention of breast cancer, as well as its prognosis. Polyphenols like natural stilbenes have been shown to be effective in chemoprevention by exerting cytotoxic effects that can stall cell proliferation. Besides possessing antioxidant properties against the DNA-damaging effects of reactive oxygen species, stilbenes have also been observed to modulate cell-signaling pathways. With the increasing trend of early-life screening for hereditary breast cancer risks, the potency of different phytochemicals in harnessing the epigenetic biomarkers of breast cancer risk demand more investigation. This review will explore means of exploiting the abilities of stilbenes in altering the underlying factors that influence breast cancer risk, as well as the appearance of associated biomarkers.

Molecular mechanisms involved in DNA repair in human cancers: An overview of PI3k/Akt signaling and PIKKs crosstalk

The cellular genome is frequently subjected to abundant endogenous and exogenous factors that induce DNA damage. Most of the Phosphatidylinositol 3-kinase-related kinases (PIKKs) family members are activated in response to DNA damage and are the most important DNA damage response (DDR) proteins. The DDR system protects the cells against the wrecking effects of these genotoxicants and repairs the DNA damage caused by them. If the DNA damage is severe, such as when DNA is the goal of chemo-radiotherapy, the DDR drives cells toward cell cycle arrest and apoptosis. Some intracellular pathways, such as PI3K/Akt, which is overactivated in most cancers, could stimulate the DDR process and failure of chemo-radiotherapy with the increasing repair of damaged DNA. This signaling pathway induces DNA repair through the regulation of proteins that are involved in DDR like BRCA1, HMGB1, and P53. In this review, we will focus on the crosstalk of the PI3K/Akt and PIKKs involved in DDR and then discuss current achievements in the sensitization of cancer cells to chemo-radiotherapy by PI3K/Akt inhibitors.

Molecular epigenetic dynamics in breast carcinogenesis

Breast cancer has become one of the most common dreadful diseases that target women across the globe. The most obvious reasons we associate with it are either genetic mutations or dysregulation of pathways. However, there is yet another domain that has a significant role in influencing the genetic mutations and pathways. Epigenetic mechanisms influence these pathways either independently or in association with genetic mutations, thereby expediting the process of breast carcinogenesis. Breast cancer is governed by various transduction pathways such as PI3K/AKT/mTOR, NOTCH, β Catenin, NF-kB, Hedgehog, etc. There are many proteins as well that serve to be tumor suppressors but somehow lose their ability to function. This may be because of either genetic mutation or a process that represses their function. Apart from these, there are a lot of individual factors like puberty, breastfeeding, abortion, parity, circadian rhythm, alcohol consumption, pollutants, and obesity that drive these mutations and hence alter the pathways. Epigenetic mechanisms like DNA methylation, histone modifications, and lncRNAs directly or indirectly bring alterations in the proteins that are involved in the pathways. They do this by either promoting the transcription of genes or by repressing it at the ground genetic level that advances breast carcinogenesis. Epigenetics precedes genetic mutation in driving carcinogenesis and so, it needs to be explored further to diversify the possibilities of target specific treatments. In this review, the general role of DNA methylation, histone modification, and lncRNAs in breast cancer and their role in influencing the oncogenic signaling pathways along with the various factors governing them have been discussed for a better understanding of the role of epigenetics in breast carcinogenesis.

Migration and Adhesion of B-Lymphocytes to Specific Microenvironments in Mantle Cell Lymphoma: Interplay between Signaling Pathways and the Epigenetic Landscape

Lymphocyte migration to and sequestration in specific microenvironments plays a crucial role in their differentiation and survival. Lymphocyte trafficking and homing are tightly regulated by signaling pathways and is mediated by cytokines, chemokines, cytokine/chemokine receptors and adhesion molecules. The production of cytokines and chemokines is largely controlled by transcription factors in the context of a specific epigenetic landscape. These regulatory factors are strongly interconnected, and they influence the gene expression pattern in lymphocytes, promoting processes such as cell survival. The epigenetic status of the genome plays a key role in regulating gene expression during many key biological processes, and it is becoming more evident that dysregulation of epigenetic mechanisms contributes to cancer initiation, progression and drug resistance. Here, we review the signaling pathways that regulate lymphoma cell migration and adhesion with a focus on Mantle cell lymphoma and highlight the fundamental role of epigenetic mechanisms in integrating signals at the level of gene expression throughout the genome.

Phosphatidylinositol 3-kinase (PI3K) inhibitors: a recent update on inhibitor design and clinical trials (2016-2020)

Introduction: The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway plays a central role in regulating cell growth and proliferation and thus has been considered as effective anticancer drug targets. Many PI3K inhibitors have been developed and progressed to various stages of clinical trials, and some have been approved as anticancer treatment. In this review, we discuss the drug design and clinical development of PI3K inhibitors over the past 4 years. We review the selectivity and potency of 47 PI3K inhibitors. Structural determinants for increasing selectivity toward PI3K subtype-selectivity or mutant selectivity are discussed. Future research direction and current clinical development in combination therapy of inhibitors involved in PI3Ks are also discussed.Area covered: This review covers clinical trial reports and patent literature on PI3K inhibitors and their selectivity published between 2016 and 2020.Expert opinion: To PI3Kα mutants (E542K, E545K, and H1047R), it is highly desirable to design and develop mutant-specific PI3K inhibitors. It is also necessary to develop subtype-selective PI3Kα inhibitors to minimize toxicity. To reduce drug resistance and to improve efficacy, future studies should include combination therapy of PI3K inhibitors with existing anticancer drugs from different pathways.

ANLN, Regulated by SP2, Promotes Colorectal Carcinoma Cell Proliferation via PI3K/AKT and MAPK Signaling Pathway

BACKGROUND

Aberrant expression of Anillin (ANLN) has been shown to function in the development of multiple cancers. However, its effects on colorectal carcinoma (CRC) remain unclear. We aimed to explore the role of ANLN in CRC development.

METHODS

By real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, and immunohistochemistry (IHC), we assessed the expression level of ANLN in CRC tissues and cell lines. The role of ANLN in CRC cell proliferation was evaluated by CCK-8 assays, colony formation assays, EdU assays and cell cycle assays. A mouse tumorigenic model was established to evaluate the in vivo function of ANLN.

RESULTS

We found that ANLN was overexpressed in CRC tissues and cell lines. Highly expressed ANLN correlated with tumor size, tumor number, and stage in patients with CRC. Silencing ANLN in CRC cell lines suppressed proliferation both in vitro and in vivo and induced G0/G1 cell cycle arrest. Downregulation of ANLN led to reduced phosphorylated levels of AKT and ERK. However, total AKT protein showed no change. SP2, a critical transcription factor, was implicated in the upregulation of ANLN.

CONCLUSIONS

Our study demonstrated that ANLN regulates CRC cell proliferation via the PI3K/AKT and MAPK pathways, indicating that ANLN may represent a novel and effective target for CRC treatment.

Identification of potential candidate genes for lip and oral cavity cancer using network analysis

Lip and oral cavity cancer, which can occur in any part of the mouth, is the 11th most common type of cancer worldwide. The major obstacles to patients' survival are the poor prognosis, lack of specific biomarkers, and expensive therapeutic alternatives. This study aimed to identify the main genes and pathways associated with lip and oral cavity carcinoma using network analysis and to analyze its molecular mechanism and prognostic significance further. In this study, 472 genes causing lip and oral cavity carcinoma were retrieved from the DisGeNET database. A protein-protein interaction network was developed for network analysis using the STRING database. VEGFA, IL6, MAPK3, INS, TNF, MAPK8, MMP9, CXCL8, EGF, and PTGS2 were recognized as network hub genes using the maximum clique centrality algorithm available in cytoHubba, and nine potential drug candidates (ranibizumab, siltuximab, sulindac, pomalidomide, dexrazoxane, endostatin, pamidronic acid, cetuximab, and apricoxib) for lip and oral cavity cancer were identified from the DGIdb database. Gene enrichment analysis was also performed to identify the gene ontology categorization of cellular components, biological processes, molecular functions, and biological pathways. The genes identified in this study could furnish a new understanding of the underlying molecular mechanisms of carcinogenesis and provide more reliable biomarkers for early diagnosis, prognostication, and treatment of lip and oral cavity cancer.

The Role of KDM2B and EZH2 in Regulating the Stemness in Colorectal Cancer Through the PI3K/AKT Pathway

Background: The incidence of colorectal cancer (CRC) has been increasing worldwide in recent years. Targeting cancer stem cells (CSCs) in CRC remains a difficult challenge. KDM2B and EZH2 play important role in the maintenance of CSCs' self-renewal capacity and tumorigenic ability; however, the biological functions of those genes in CRC remain unclear. In this study, we aimed to define the contribution of the expression of KDM2B in the features of CRC and establish the relationship between KDM2B and EZH2 in colorectal CSCs.

Methods: The expression of KDM2B and EZH2 in the specimens of CRC and CRC cell lines were analyzed by immunohistochemistry, Western blot, and immunofluorescence. The underlying mechanisms of altered expressions of KDM2B and EZH2 and their impact on the biologic features of CRC and stemness in CRC were investigated.

Results: The KDM2B gene was highly expressed in CRC tissues, and its overexpression positively correlated with tumor stages and tumor/node/metastasis (TNM) classification. The downregulation of KDM2B retarded cell proliferation, induced DNA damage, reduced spheroid formation, and decreased CRC stem cell markers: CD44, CD133, and ALDH-1. Moreover, the downregulation of KDM2B decreased the expression of EZH2 and both regulated cell migration, invasion, and stemness in the CRC cell line. Additionally, the interaction between KDM2B and EZH2 significantly increased the components of the PI3K/AKT pathway including AKT and PI3K. The high expression of KDM2B positively correlated with EZH2 in CRC tissues.

Conclusion: This study shows that the downregulation of KDM2B and EZH2 can regulate CRC cell stemness, and their interaction may serve as a novel prognostic marker and therapeutic target for patients with CRC.