NEDD9 promotes cancer stemness by recruiting myeloid-derived suppressor cells via CXCL8 in esophageal squamous cell carcinoma

Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy and radiotherapy failures.Myeloid-derived suppressor cells(MDSCs),in contrast,are known to be involved in mediating immunosuppression.Here,we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.Methods:ESCC tissues and cell lines were evaluated.Neural precursor cell expressed,developmentally downregulated 9(NEDD9)was knocked down and overexpressed by lentiviral transfection.Quantitative PCR,Western blot,immunohistochemistry,cell invasion,flow cytometry,cell sorting,multiplex chemokine profiling,and tumor growth analyses were performed.Results:Microarray analysis revealed 10 upregulated genes in esophageal CSCs.Only NEDD9 was upregulated in CSCs using the sphere-forming method.NEDD9 expression was correlated with tumor invasion(P=0.0218),differentiation(P=0.0153),and poor prognosis(P=0.0373).Additionally,NEDD9 was required to maintain the stem-like phenotype.Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8(CXCL8)expression via the ERK pathway.CXCL8 mediated the recruitment of MDSCs induced by NEDD9 in vitro and in vivo.MDSCs promoted the stemness of ESCC cells through NEDD9 via the Notch pathway.Conclusions:As a marker of ESCC,NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor,suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.

Colon cancer stemness as a reversible epigenetic state:Implications for anticancer therapies

The recent discovery of cancer cell plasticity,i.e.their ability to reprogram into cancer stem cells(CSCs)either naturally or under chemotherapy and/or radiotherapy,has changed,once again,the way we consider cancer treatment.If cancer stemness is a reversible epigenetic state rather than a genetic identity,opportunities will arise for therapeutic strategies that remodel epigenetic landscapes of CSCs.However,the systematic use of DNA methyltransferase and histone deacetylase inhibitors,alone or in combination,in advanced solid tumors including colorectal cancers,regardless of their molecular subtypes,does not seem to be the best strategy.In this review,we first summarize the knowledge researchers have gathered on the epigenetic signatures of CSCs with the difficulty of isolating rare populations of cells.We raise questions about the relevant use of currently available epigenetic inhibitors(epidrugs)while the expression of numerous cancer stem cell markers are often repressed by epigenetic mechanisms.These markers include the three cluster of differentiation CD133,CD44 and CD166 that have been extensively used for the isolation of colon CSCs.and.Finally,we describe current treatment strategies using epidrugs,and we hypothesize that,using correlation tools comparing associations of relevant CSC markers with chromatin modifier expression,we could identify better candidates for epienzyme targeting.

Knockdown of circular RNA (CircRNA)_001896 inhibits cervical cancer proliferation and stemness in vivo and in vitro

Objective:Previous studies indicated that aberrant circular RNA(circRNA)expression affects gene expression regulatory networks,leading to the aberrant activation of tumor pathways and promoting tumor cell growth.However,the expression,clinical significance,and effects on cell propagation,invasion,and dissemination of circRNA_001896 in cervical cancer(CC)tissues remain unclear.Methods:The Gene Expression Omnibus(GEO)datasets(GSE113696 and GSE102686)were used to examine differential circRNA expression in CC and adjacent tissues.The expression of circRNA_001896 was detected in 72 CC patients usingfluorescence quantitative PCR.Correlation analysis with clinical pathological features was performed through COX multivariate and univariate analysis.The effect of circRNA_001896 downregulation on CC cell propagation was examined using the cell counting kit-8(CCK-8)test,clonogenic,3D sphere formation,and in vivo tumorigenesis assays.Results:Intersection of the GSE113696 and GSE102686 datasets revealed an increased expression of four circRNAs,including circRNA_001896,in CC tissues.Fluorescence quantitative PCR confirmed circRNA_001896 as a circular RNA.High expression of circRNA_001896 was considerably associated with lymph node metastasis,International Federation of Gynecologists and Obstetricians(FIGO)stage,tumor diameter,and survival period in CC patients.Proportional hazards model(COX)univariate and multivariate analyses revealed that circRNA_001896 expressions are a distinct risk factor affecting CC patients’prognosis.Cellular functional experiments showed that downregulating circRNA_001896 substantially suppressed CC cell growth,colony formation,and 3D sphere-forming ability.In vivo,tumorigenesis analysis in nude mice demonstrated that downregulating circRNA_001896 remarkably reduced the in vivo proliferation capacity of CC cells.Conclusion:CircRNA_001896 is highly expressed in CC tissues and is substantially related to lymph node metastasis,FIGO stage,tumor size,and survival period in patients.Moreover,downregulating circRNA_001896 significantly inhibits both in vivo and in vitro propagation of CC cells.Therefore,circRNA_001896 might be used as a biomarker for targeted therapy in cervical cancer.

VX-509 attenuates the stemness characteristics of colorectal cancer stem-like cells by regulating the epithelial-mesenchymal transition through Nodal/Smad2/3 signaling

BACKGROUND Colorectal cancer stem cells(CCSCs)are heterogeneous cells that can self-renew and undergo multidirectional differentiation in colorectal cancer(CRC)patients.CCSCs are generally accepted to be important sources of CRC and are responsible for the progression,metastasis,and therapeutic resistance of CRC.Therefore,targeting this specific subpopulation has been recognized as a promising strategy for overcoming CRC.AIM To investigate the effect of VX-509 on CCSCs and elucidate the underlying mechanism.METHODS CCSCs were enriched from CRC cell lines by in conditioned serum-free medium.Western blot,Aldefluor,transwell and tumorigenesis assays were performed to verify the phenotypic characteristics of the CCSCs.The anticancer efficacy of VX-509 was assessed in HCT116 CCSCs and HT29 CCSCs by performing cell viability analysis,colony formation,sphere formation,flow cytometry,and western blotting assessments in vitro and tumor growth,immunohistochemistry and immunofluorescence assessments in vivo.RESULTS Compared with parental cells,sphere cells derived from HCT116 and HT29 cells presented increased expression of stem cell transcription factors and stem cell markers and were more potent at promoting migration and tumori-genesis,demonstrating that the CRC sphere cells displayed CSC features.VX-509 inhibited the tumor malignant biological behavior of CRC-stem-like cells,as indicated by their proliferation,migration and clonality in vitro,and suppressed the tumor of CCSC-derived xenograft tumors in vivo.Besides,VX-509 suppressed the CSC character-istics of CRC-stem-like cells and inhibited the progression of epithelial-mesenchymal transition(EMT)signaling in vitro.Nodal was identified as the regulatory factor of VX-509 on CRC stem-like cells through analyses of differen-tially expressed genes and CSC-related database information.VX-509 markedly downregulated the expression of Nodal and its downstream phosphorylated Smad2/3 to inhibit EMT progression.Moreover,VX-509 reversed the dedifferentiation of CCSCs and inhibited the progression of EMT induced by Nodal overexpression.CONCLUSION VX-509 prevents the EMT process in CCSCs by inhibiting the transcription and protein expression of Nodal,and inhibits the dedifferentiated self-renewal of CCSCs.

UBE2T mediates the stemness properties of breast cancer cells through the mTOR signaling pathway

Objectives:This study aimed to reveal the role and possible mechanism of the ubiquitin-conjugating enzyme 2T(UBE2T)in the biological activities of breast cancer stem cells(BCSCs).Methods:The specific protein and gene expression were quantified by Western blotting and quantitative real-time polymerase chain reaction,the proportion of BCSCs was examined by flow cytometry,and the self-renewal and proliferation of BCSCs were verified by serial sphere formation and soft agar.Results:Increasing expression of UBE2T was drastically found in breast cancer than that in adjacent tissues.Furthermore,UBE2T overexpression significantly increased the proportion of BCSCs in breast cancer cells and promoted their self-renewal and proliferation.Silent UBE2T exhibited the opposite functions.UBE2T increased the levels of the mammalian target of rapamycin and the phosphorylated mammalian target of rapamycin.Mammalian target of rapamycin(mTOR)inhibitor rapamycin inhibited the function of UBE2T in BCSCs.Conclusion:UBE2T plays a role in BCSCs through mTOR pathway and may suggest a novel therapeutic strategy for breast cancer.

Prostaglandin D2 regulation of autophagy affects stemness of gastric cancer stem cells

Objective:To explore the effect and mechanism of prostaglandins D2(PGD2)on the stemness of gastric cancer stem cells(GCSCs).Methods:7901-GCSCs were enriched by serum-free culture method;then the positivity rate of CD44,a stemness marker,was detected by flow cytometry in serum-free cultured 7901-GCSCs;the sphere-forming ability was detected by the sphere-forming assay after stimulation with different concentrations of PGD2(2.5,5,10)μg/mL,and the expression of stemness-related indicators(OCT4,CD44)and autophagyrelated proteins(LC3,Beclin-1)after PGD2 stimulation was detected by the western blot assay in different concentrations.The expression of stemness-related indexes(OCT4,CD44)and autophagy-related proteins(LC3,Beclin-1)were detected by Western blot assay after stimulation with different concentrations of PGD2.The expression of autophagy-related proteins after stimulation with different concentrations of CQ(2.5,5,10)μM was detected by Western blot experiment.The protein expression of autophagy-related proteins(LC3,Beclin-1)and stemness-related indexes(OCT4,CD44)was detected by Western blot experiment after PGD2 as well as PGD2+CQ treatment.Results:Flow cytometry results showed that the expression of CD44 positivity was increased in serum-free cultured 7901-GCSCs compared with gastric cancer cells SGC-7901(P<0.05),which fulfilled the needs of subsequent experiments.The results of stem cell spheroid formation assay showed that the spheroid formation ability of 7901-GCSCs in the PGD2 group was significantly weakened compared with that of the DMSO group(P<0.05).Western blot results showed that the protein expression of stemness-related indexes(OCT4,CD44)was down-regulated in the 7901-GCSCs in the PGD2 group compared with that of the DMSO group(P<0.05),and the expression of autophagy-related proteins(LC3,Beclin-1)expression increased(P<0.05).Compared with the DMSO group,the expression of autophagy-related proteins(LC3,Beclin-1)was decreased in the CQ group(P<0.05).Western blot results also showed that the expression of cellular autophagy-related proteins and stemness-related indexes in the PGD2+CQ group was not significantly changed compared with that of the DMSO group(ns:the difference was not significant),suggesting that the CQ could block the effect of PGD2 on the expression of stemness markers in 7901-GCSCs.7901-GCSCs stemness inhibition.Conclusion:PGD2 may affect the stemness of 7901-GCSCs by regulating autophagy.

Research Progress of Breast Cancer Stem Cell Stemness and Breast Cancer Recurrence

Currently, breast cancer is the most common malignant tumour in Chinese women with a high incidence rate, and recurrence and metastasis are the main reasons affecting survival. Breast Cancer Stem Cells (BCSCs) are stem cells capable of continuous regeneration in vivo with strong self-renewal ability and multidirectional differentiation potential, which are highly tumourigenic and insensitive to radiotherapy and chemotherapy, and are highly susceptible to breast cancer recurrence. Therefore, exploring the stemness of BCSCs and their mechanism associated with recurrence is important for developing new therapeutic strategies, improving therapeutic efficacy, and improving patient prognosis.

Oleanolic acid inhibits colon cancer cell stemness and reverses chemoresistance by suppressing JAK2/STAT3 signaling pathway

Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.

Jiedu Recipe,a compound Chinese herbal medicine,inhibits cancer stemness in hepatocellular carcinoma via Wnt/β-catenin pathway under hypoxia

Objective Jiedu Recipe(JR),a Chinese herbal remedy,has been shown to prolong overall survival time and decrease recurrence and metastasis rates in patients with hepatocellular carcinoma(HCC).This work investigated the mechanism of JR in HCC treatment.Methods The chemical constituents of JR were detected using liquid chromatography-mass spectrometry.The potential anti-HCC mechanism of JR was screened using network pharmacology and messenger ribonucleic acid(mRNA)microarray chip assay,followed by experimental validation in human HCC cells(SMMC-7721 and Huh7)in vitro and a nude mouse subcutaneous transplantation model of HCC in vivo.HCC cell characteristics of proliferation,migration and invasion under hypoxic setting were investigated using thiazolyl blue tetrazolium bromide,wound healing and Transwell assays,respectively.Image-i^(TM)Hypoxia Reagent was added to reveal hypoxic conditions.Stem cell sphere formation assay was used to detect the stemness.Epithelial-mesenchymal transition(EMT)markers like E-cadherin,vimentin andα-smooth muscle actin,and pluripotent transcription factors including nanog homeobox,octamer-binding transcription factor 4,and sex-determining region Y box protein 2 were analyzed using Western blotting and real-time polymerase chain reaction.Western blot was performed to ascertain the anti-HCC effect of JR under hypoxia involving the Wnt/β-catenin pathway.Results According to network pharmacology and mRNA microarray chip analysis,JR may potentially act on hypoxia and inhibit the Wnt/β-catenin pathway.In vitro and in vivo experiments showed that JR significantly decreased hypoxia,and suppressed HCC cell features of proliferation,migration and invasion;furthermore,the hypoxia-induced increases in EMT and stemness marker expression in HCC cells were inhibited by JR.Results based on the co-administration of JR and an agonist(LiCl)or inhibitor(IWR-1-endo)verified that JR suppressed HCC cancer stem-like properties under hypoxia by blocking the Wnt/β-catenin pathway.Conclusion JR exerts potent anti-HCC effects by inhibiting cancer stemness via abating the Wnt/β-catenin pathway under hypoxic conditions.

Baicalin Antagonizes Prostate Cancer Stemness via Inhibiting Notch1/NF-κB Signaling Pathway

Objective To investigate the molecular mechanisms underlying the effect of baicalin on prostate cancer(PCa)progression both in vivo and in vitro.Methods The in situ PCa stem cells(PCSCs)-injected xenograft tumor models were established in BALB/c nude mice.Tumor volume and weight were respectively checked after baicalin(100 mg/kg)treatment.Hematoxylin-eosin(HE)staining was used to observe the growth arrest and cell necrosis.mRNA expression levels of acetaldehyde dehydrogenase 1(ALDH1),CD44,CD133 and Notch1 were determined by reverse transcription-polymerase chain reaction.Protein expression levels of ALDH1,CD44,CD133,Notch1,nuclear factorκB(NF-κB)P65 and NF-κB p-P65 were detected by Western blot.Expression and subcellular location of ALDH1,CD44,CD133,Notch1 and NF-κB p65 were detected by immunofluorescence analysis.In vitro,cell cycle distribution and cell apoptosis of PC3 PCSCs was assessed by flow cytometry after baicalin(125µmol/L)treatment.The migration and invasion abilities of PCSCs were assessed using Transwell assays.Transmission electron microscopy scanning was utilized to observe the structure and autophagosome formation of baicalin-treated PCSCs.In addition,PCSCs were infected with lentiviruses expressing human Notch1.Results Compared with the control group,the tumor volume and weight were notably reduced in mice treated with 100 mg/kg baicalin(P<0.05 or P<0.01).Histopathological analysis showed that baicalin treatment significantly inhibited cell proliferation and promoted cell apoptosis.Furthermore,baicalin treatment reduced mRNA and protein expression levels of CD44,CD133,ALDH1,and Notch1 as well as the protein expression of NF-κB p-P65 in the xenograft tumor(P<0.01).In vitro,the cell proliferation of PCSCs was significantly attenuated after treatment with 125µmol/L baicalin for 72 h(P<0.01).The cell migration and invasion rates were decreased following treatment with baicalin for 48 and 72 h(P<0.01).Baicalin notably induced cell apoptosis and seriously damaged the structure of PCSCs.The mRNA and protein expressions of CD133,CD44,ALDH1 and Notch1 in PCSCs were significantly downregulated following baicalin treatment(P<0.01).Importantly,the inhibitory effects of baicalin on PCa progression and stemness were reversed by Notch1 overexpression(P<0.05 or P<0.01).Conclusion Mechanistically,baicalin exhibited a potential therapeutic effect on PCa via inhibiting the Notch1/NF-κB signaling pathway and its mediated cancer stemness.

Physical exercise suppresses hepatocellular carcinoma progression by alleviating hypoxia and attenuating cancer stemness through the Akt/GSK-3β/β-catenin pathway

Objective:Physical exercise,a common non-drug intervention,is an important strategy in cancer treatment,including hepatocellular carcinoma(HCC).However,the mechanism remains largely unknown.Due to the importance of hypoxia and cancer stemness in the development of HCC,the present study investigated whether the anti-HCC effect of physical exercise is related to its suppression on hypoxia and cancer stemness.Methods:A physical exercise intervention of swimming(30 min/d,5 d/week,for 4 weeks)was administered to BALB/c nude mice bearing subcutaneous human HCC tumor.The anti-HCC effect of swimming was assessed in vivo by tumor weight monitoring,hematoxylin and eosin(HE)staining,and immunohistochemistry(IHC)detection of proliferating cell nuclear antigen(PCNA)and Ki67.The expression of stemness transcription factors,including Nanog homeobox(NANOG),octamer-binding transcription factor 4(OCT-4),v-Myc avian myelocytomatosis viral oncogene homolog(C-MYC)and hypoxia-inducible factor-1a(HIF-1a),was detected using real-time reverse transcription polymerase chain reaction.A hypoxia probe was used to explore the intratumoral hypoxia status.Western blot was used to detect the expression of HIF-1a and proteins related to protein kinase B(Akt)/glycogen synthase kinase-3β(GSK-3β)/β-catenin signaling pathway.The IHC analysis of platelet endothelial cell adhesion molecule-1(CD31),and the immunofluorescence co-location of CD31 and desmin were used to analyze tumor blood perfusion.SMMC-7721 cells were treated with nude mice serum.The inhibition effect on cancer stemness in vitro was detected using suspension sphere experiments and the expression of stemness transcription factors.The hypoxia status was inferred by measuring the protein and mRNA levels of HIF-1a.Further,the expression of proteins related to Akt/GSK-3β/β-catenin signaling pathway was detected.Results:Swimming significantly reduced the body weight and tumor weight in nude mice bearing HCC tumor.HE staining and IHC results showed a lower necrotic area ratio as well as fewer PCNA or Ki67 positive cells in mice receiving the swimming intervention.Swimming potently alleviated the intratumoral hypoxia,attenuated the cancer stemness,and inhibited the Akt/GSK-3β/β-catenin signaling pathway.Additionally,the desmin+/CD31+ratio,rather than the number of CD31+vessels,was significantly increased in swimming-treated mice.In vitro experiments showed that treating cells with the serum from the swimming intervention mice significantly reduced the formation of SMMC-7721 cell suspension sphere,as well as the m RNA expression level of stemness transcription factors.Consistent with the in vivo results,HIF-1a and Akt/GSK-3β/β-catenin signaling pathway were also inhibited in cells treated with serum from swimming group.Conclusion:Swimming alleviated hypoxia and attenuated cancer stemness in HCC,through suppression of the Akt/GSK-3β/β-catenin signaling pathway.The alleviation of intratumoral hypoxia was related to the increase in blood perfusion in the tumor.

BMP signaling in cancer stemness and differentiation

The BMP(Bone morphogenetic protein)signaling pathway plays a central role in metazoan biology,intricately shaping embryonic development,maintaining tissue homeostasis,and influencing disease progression.In the context of cancer,BMP signaling exhibits context-dependent dynamics,spanning from tumor suppression to promotion.Cancer stem cells(CSCs),a modest subset of neoplastic cells with stem-like attributes,exert substantial influence by steering tumor growth,orchestrating therapy resistance,and contributing to relapse.A comprehensive grasp of the intricate interplay between CSCs and their microenvironment is pivotal for effective therapeutic strategies.Among the web of signaling pathways orchestrating cellular dynamics within CSCs,BMP signaling emerges as a vital conductor,overseeing CSC self-renewal,differentiation dynamics,and the intricate symphony within the tumor microenvironment.Moreover,BMP signaling’s influence in cancer extends beyond CSCs,intricately regulating cellular migration,invasion,and metastasis.This multifaceted role underscores the imperative of comprehending BMP signaling’s contributions to cancer,serving as the foundation for crafting precise therapies to navigate multifaceted challenges posed not only by CSCs but also by various dimensions of cancer progression.This article succinctly encapsulates the diverse roles of the BMP signaling pathway across different cancers,spanning glioblastoma multiforme(GBM),diffuse intrinsic pontine glioma(DIPG),colorectal cancer,acute myeloid leukemia(AML),lung cancer,prostate cancer,and osteosarcoma.It underscores the necessity of unraveling underlying mechanisms and molecular interactions.By delving into the intricate tapestry of BMP signaling’s engagement in cancers,researchers pave the way for meticulously tailored therapies,adroitly leveraging its dualistic aspects-whether as a suppressor or promoter-to effectively counter the relentless march of tumor progression.

How the interplay among the tumor microenvironment and the gut microbiota influences the stemness of colorectal cancer cells

Colorectal cancer(CRC)remains the third most prevalent cancer disease and involves a multi-step process in which intestinal cells acquire malignant characteristics.It is well established that the appearance of distal metastasis in CRC patients is the cause of a poor prognosis and treatment failure.Nevertheless,in the last decades,CRC aggressiveness and progression have been attributed to a specific cell population called CRC stem cells(CCSC)with features like tumor initiation capacity,self-renewal capacity,and acquired multidrug resistance.Emerging data highlight the concept of this cell subtype as a plastic entity that has a dynamic status and can be originated from different types of cells through genetic and epigenetic changes.These alterations are modulated by complex and dynamic crosstalk with environmental factors by paracrine signaling.It is known that in the tumor niche,different cell types,structures,and biomolecules coexist and interact with cancer cells favoring cancer growth and development.Together,these components constitute the tumor microenvironment(TME).Most recently,researchers have also deepened the influence of the complex variety of microorganisms that inhabit the intestinal mucosa,collectively known as gut microbiota,on CRC.Both TME and microorganisms participate in inflammatory processes that can drive the initiation and evolution of CRC.Since in the last decade,crucial advances have been made concerning to the synergistic interaction among the TME and gut microorganisms that condition the identity of CCSC,the data exposed in this review could provide valuable insights into the biology of CRC and the development of new targeted therapies.

Role of cancer stem cell ecosystem on breast cancer metastasis and related mouse models

Breast cancer metastasis is responsible for most breast cancer-related deaths and is influenced by many factors within the tumor ecosystem,including tumor cells and microenvironment.Breast cancer stem cells(BCSCs)constitute a small population of cancer cells with unique characteristics,including their capacity for self-renewal and differentiation.Studies have shown that BCSCs not only drive tumorigenesis but also play a crucial role in promoting metastasis in breast cancer.The tumor microenvironment(TME),composed of stromal cells,immune cells,blood vessel cells,fibroblasts,and microbes in proximity to cancer cells,is increasingly recognized for its crosstalk with BCSCs and role in BCSC survival,growth,and dissemination,thereby influencing metastatic ability.Hence,a thorough understanding of BCSCs and the TME is critical for unraveling the mechanisms underlying breast cancer metastasis.In this review,we summarize current knowledge on the roles of BCSCs and the TME in breast cancer metastasis,as well as the underlying regulatory mechanisms.Furthermore,we provide an overview of relevant mouse models used to study breast cancer metastasis,as well as treatment strategies and clinical trials addressing BCSC-TME interactions during metastasis.Overall,this study provides valuable insights for the development of effective therapeutic strategies to reduce breast cancer metastasis.

Effect of colorectal cancer stem cells on the development and metastasis of colorectal cancer

The relevant mechanism of tumor-associated macrophages(TAMs)in the treatment of colorectal cancer patients with immune checkpoint inhibitors(ICIs)is discussed,and the application prospects of TAMs in reversing the treatment tolerance of ICIs are discussed to provide a reference for related studies.As a class of drugs widely used in clinical tumor immunotherapy,ICIs can act on regulatory molecules on cells that play an inhibitory role-immune checkpoints-and kill tumors in the form of an immune response by activating a variety of immune cells in the immune system.The sensitivity of patients with different types of colorectal cancer to ICI treatment varies greatly.The phenotype and function of TAMs in the colorectal cancer microenvironment are closely related to the efficacy of ICIs.ICIs can regulate the phenotypic function of TAMs,and TAMs can also affect the tolerance of colorectal cancer to ICI therapy.TAMs play an important role in ICI resistance,and making full use of this target as a therapeutic strategy is expected to improve the immunotherapy efficacy and prognosis of patients with colorectal cancer.

Multifaceted role of microRNAs in gastric cancer stem cells: Mechanisms and potential biomarkers

MicroRNAs(miRNAs)have received much attention in the past decade as potential key epigenomic regulators of tumors and cancer stem cells(CSCs).The abnormal expression of miRNAs is responsible for different phenotypes of gastric cancer stem cells(GCSCs).Some specific miRNAs could be used as promising biomarkers and therapeutic targets for the identification of GCSCs.This review summarizes the coding process and biological functions of miRNAs and demon-strates their role and efficacy in gastric cancer(GC)metastasis,drug resistance,and apoptosis,especially in the regulatory mechanism of GCSCs.It shows that the overexpression of onco-miRNAs and silencing of tumor-suppressor miRNAs can play a role in promoting or inhibiting tumor metastasis,apart from the initial formation of GC.It also discusses the epigenetic regulation and potential clinical applications of miRNAs as well as the role of CSCs in the pathogenesis of GC.We believe that this review may help in designing novel therapeutic approaches for GC.

Research progress on lung cancer stem cells in epidermal growth factor receptor–tyrosine kinase inhibitor targeted therapy resistance in lung adenocarcinoma

Lung cancer is the leading cause of cancer-related deaths globally.In recent years,with the widespread use of genetic testing,epidermal growth factor receptor–tyrosine kinase inhibitor(EGFR-TKI)–targeted drugs have been efficacious to patients with lung adenocarcinoma exhibiting EGFR mutations.However,resistance to treatment is inevitable and eventually leads to tumor progression,recurrence,and reduction in the overall treatment efficacy.Lung cancer stem cells play a crucial role in the development of resistance toward EGFR-TKI–targeted therapy for lung adenocarcinoma.Lung cancer stem cells possess self-renewal,multilineage differentiation,and unlimited proliferation capabilities,which efficiently contribute to tumor formation and ultimately lead to tumor recurrence andmetastasis.In this study,we evaluated the origin,markers,stemness index,relevant classic studies,resistance mechanisms,related signaling pathways,and strategies for reversing lung cancer stem cell resistance to EGFR-TKIs to provide new insights on delaying or reducing resistance and to improve the treatment efficacy of patients with EGFR-mutated lung adenocarcinoma in the future.

Exploring the Pivotal Association of AI in Cancer Stem Cells Detection and Treatment

Cancer stem cells(CSCs),or tumor-initiating cells(TICs),are cancerous cell subpopulations that remain while tumor cells propagate as a unique subset and exhibit multiple applications in several diseases.They are responsible for cancer cell initiation,development,metastasis,proliferation,and recurrence due to their self-renewal and differentiation abilities in many kinds of cells.Artificial intelligence(AI)has gained significant attention because of its vast applications in various fields including agriculture,healthcare,transportation,and robotics,particularly in detecting human diseases such as cancer.The division and metastasis of cancerous cells are not easy to identify at early stages due to their uncontrolled situations.It has provided some real-time pictures of cancer progression and relapse.The purpose of this review paper is to explore new investigations into the role of AI in cancer stem cell progression and metastasis and in regenerative medicines.It describes the association of machine learning and AI with CSCs along with its numerous applications from cancer diagnosis to therapy.This review has also provided key challenges and future directions of AI in cancer stem cell research diagnosis and therapeutic approach.

Advancing Cancer Stem Cell-Targeted Therapeutic Applications

Cancer stem cells(CSCs),first identified in blood cancers,are increasingly recognized as significant biomarkers and targets in tumor therapy due to their metastatic potential and role in cancer recurrence.Recent research has demonstrated the dedication of scientists in targeting CSCs to explore novel therapeutic strategies.Many types of cancer exhibit metastasis,heterogeneity,and resistance to treatment,all of which are influenced by CSCs.These cells utilize various transcription factors and signaling pathways to carry out these functions.By identifying and understanding these pathways,new therapeutic breakthroughs can be achieved.Thus,targeting cancer stem cells holds great potential and importance in cancer treatment.Moreover,CSCs offer promising avenues for treating otherwise incurable diseases.However,targeting CSCs presents challenges such as immunological rejection and disease recurrence.Advancing research into CSCs may reveal new insights in the fight against cancer and ultimately improve human health.This review explores the roles of CSCs in cancer development and treatment,aiming to uncover new therapeutic approaches.

EMT-associated microRNAs and their roles in cancer stemness and drug resistance

Epithelial-to-mesenchymal transition(EMT)is implicated in a wide array of malignant behaviors of cancers,including proliferation,invasion,and metastasis.Most notably,previou studies have indicated that both cancer stem-like properties and drug resistance were associated with EMT.Furthermore,microRNAs(miRNAs)play a pivotal role in the regulation of EMT phenotype,as a result,some miRNAs impact cancer stemness and drug resistance.Therefore,understanding the relationship between EMT-associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment.In this review,we preliminarily looked into the various roles that the EMT-associated miRNAs play in the stem-like nature of malignant cells.Then,we reviewed the interaction between EMT-associated miRNAs and the drugresistant complex signaling pathways of multiple cancers including lung cancer,gastric cancer,gynecologic cancer,breast cancer,liver cancer,colorectal cancer,pancreatic cancer,esophageal cancer,and nasopharyngeal cancer.We finally discussed the relationship between EMT,cancer stemness,and drug resistance,as well as looked forward to the potential applications of miRNA therapy for malignant tumors.