Primary research on neoplasm needle track implantation metastasis after radioactive seeds implantation and preventive measures

Objective:To observe the possibility of neoplasm needle track implantation after radioactive seeds implantation and seek preventive measures to avoid it.Methods:Superficial tissue of 250 seeding needle cores and 250 stylophores employed in neoplasm radioactive seeds implantation was smeared on slides to search for tumor cells.All patients received chemotherapy or endocrine therapy after operations.Ultrasound B-mode or computer tomography(CT)was performed at 10th day,30th day,60th day,and 180th day post operation to detect neoplasm implantation metastasis through needle tracks. Results:Positive cells were found on 13 of 250(5.20%)cores,and 7 of 250(2.80%)stylophores.The difference was not sta- tistically significant(P>0.05).The positive cells frequency of needles those traversed distance less than 3 cm in normal tissue was 6.19%(13/210),while the frequency of the others those traversed longer distance in normal tissue was 2.41%(7/290). The positive cells frequency of needles traversing different distances in normal tissues is significantly different(P<0.05).No neoplasm was detected through needle tracks by ultrasound B-mode or CT in 180 days after operation.Conclusion:Tumor cells could ablate into the needle track during radioactive seed implantation.Some preventive measures,such as optimization of pre-operation and intra-operation treatment plan,chemotherapy or endocrine therapy after operation,may be beneficial to avoid the implantation metastasis of neoplasm in seeding needle tracks.

Biological factors driving colorectal cancer metastasis

Approximately 20%of colorectal cancer(CRC)patients present with metastasis at diagnosis.Among Stage I-III CRC patients who undergo surgical resection,18%typically suffer from distal metastasis within the first three years following initial treatment.The median survival duration after the diagnosis of metastatic CRC(mCRC)is only 9 mo.mCRC is traditionally considered to be an advanced stage malignancy or is thought to be caused by incomplete resection of tumor tissue,allowing cancer cells to spread from primary to distant organs;however,increa-sing evidence suggests that the mCRC process can begin early in tumor development.CRC patients present with high heterogeneity and diverse cancer phenotypes that are classified on the basis of molecular and morphological alterations.Different genomic and nongenomic events can induce subclone diversity,which leads to cancer and metastasis.Throughout the course of mCRC,metastatic cascades are associated with invasive cancer cell migration through the circulatory system,extravasation,distal seeding,dormancy,and reactivation,with each step requiring specific molecular functions.However,cancer cells presenting neoantigens can be recognized and eliminated by the immune system.In this review,we explain the biological factors that drive CRC metastasis,namely,genomic instability,epigenetic instability,the metastatic cascade,the cancer-immunity cycle,and external lifestyle factors.Despite remarkable progress in CRC research,the role of molecular classification in therapeutic intervention remains unclear.This review shows the driving factors of mCRC which may help in identifying potential candidate biomarkers that can improve the diagnosis and early detection of mCRC cases.

RARRES2 regulates lipid metabolic reprogramming to mediate the development of brain metastasis in triple negative breast cancer

Background Triple negative breast cancer(TNBC),the most aggressive subtype of breast cancer,is characterized by a high incidence of brain metastasis(BrM)and a poor prognosis.As the most lethal form of breast cancer,BrM remains a major clinical challenge due to its rising incidence and lack of effective treatment strategies.Recent evidence suggested a potential role of lipid metabolic reprogramming in breast cancer brain metastasis(BCBrM),but the underlying mechanisms are far from being fully elucidated.Methods Through analysis of BCBrM transcriptome data from mice and patients,and immunohistochemical validation on patient tissues,we identified and verified the specific down-regulation of retinoic acid receptor responder 2(RARRES2),a multifunctional adipokine and chemokine,in BrM of TNBC.We investigated the effect of aberrant RARRES2 expression of BrM in both in vitro and in vivo studies.Key signaling pathway components were evaluated using multi-omics approaches.Lipidomics were performed to elucidate the regulation of lipid metabolic reprogramming of RARRES2.Results We found that downregulation of RARRES2 is specifically associated with BCBrM,and that RARRES2 deficiency promoted BCBrM through lipid metabolic reprogramming.Mechanistically,reduced expression of RARRES2 in brain metastatic potential TNBC cells resulted in increased levels of glycerophospholipid and decreased levels of triacylglycerols by regulating phosphatase and tensin homologue(PTEN)-mammalian target of rapamycin(mTOR)-sterol regulatory element-binding protein 1(SREBP1)signaling pathway to facilitate the survival of breast cancer cells in the unique brain microenvironment.Conclusions Our work uncovers an essential role of RARRES2 in linking lipid metabolic reprogramming and the development of BrM.RARRES2-dependent metabolic functions may serve as potential biomarkers or therapeutic targets for BCBrM.

Radiotherapy for hyoid bone metastasis from lung adenocarcinoma:A case report

BACKGROUND Metastasis to the hyoid bone is an exceptionally rare occurrence,with documented cases limited to breast,liver,colon,skin,lung,and prostate cancers.This report highlights an unusual case involving the metastasis of lung adenocarcinoma to the hyoid bone,accompanied by a distinctive headache.Previous documentation involved surgical resection of the hyoid mass.We present a case displaying the benefits of palliative radiotherapy.CASE SUMMARY A 72-year-old non-smoking,non-alcoholic woman,initially under investigation for a year-long elevation in absolute lymphocyte count,presented with a monthlong history of intermittent throat pain.Despite negative findings in gastroenterological and otolaryngologic examinations,a contrast-enhanced chest computed tomography scan revealed a mediastinal mass and questionable soft tissue thickening in her left anterolateral neck.Subsequent imaging and biopsies confirmed the presence of lung adenocarcinoma metastasis to the hyoid bone.The patient was treated with platinum-based chemo-immunotherapy along with pembrolizumab.Ultimately,the lung cancer was unresponsive.Our patient opted for palliative radiation therapy instead of surgical resection to address her throat pain.As a result,her throat pain was alleviated,and it also incidentally resolved her chronic headaches.This is the second documented case of lung adenocarcinoma metastasizing to the hyoid bone.CONCLUSION Palliative radiotherapy may add to the quality of life in symptomatic patients with cancer metastatic to the hyoid bone.

Is primary transcatheter aortic valve implantation the new normal?

Degenerative calcific aortic valve stenosis(AS)is the most common valvular heart disease in elderly.^[1] It is well documented that symptomatic severe AS follows a malignant course leading to cardiogenic shock(CS).

Solitary extraovarian primary peritoneal carcinoma with direct invasion into the liver,diaphragm and lung without peritoneal dissemination or distant metastasis

To the Editor:Extraovarian primary peritoneal carcinoma(EOPPC)is an uncommon malignancy with many similarities to epithelial ovarian carcinoma in histological,clinical,and etiological aspects[1].This phenomenon is explained by their common embryonal origin,in which both develop from the coelomic epithelium in the early embryological stage.Despite their similarities,the incidence of EOPPC is significantly lower than that of epithelial ovarian carcinoma(6.78 cases per million vs.120.5 cases per million)[1].

Nursing Care and Causative Analysis of Grade IV Capsular Contracture Following Breast Cancer Expander Implantation

Objective: By observing the treatment and nursing care of a patient with Grade IV capsular contracture following breast cancer expander implantation and subsequent Stage II reconstruction, we aim to analyze the reasons for the formation of capsular contracture after Stage I expander implantation and prevent its recurrence following Stage II reconstruction. Methods: In May 2020, the patient noticed an increase in the size of a breast mass. In August, she underwent AC-THP neoadjuvant chemotherapy, followed by a “right breast-conserving nipple-areolar subglandular excision + right axillary lymph node dissection + expander implantation” surgery in November 2020. Radiation therapy began in January 2021. During radiation therapy, the patient experienced severe breast hardening, distortion, tenderness, and was diagnosed with Grade IV capsular contracture. To relieve the capsular contracture, the patient underwent a “contracted capsule incision and release procedure + removal of the right breast expander + right breast implantation” surgery in July 2021. Postoperatively, measures were taken to prevent incision infection, emphasizing aseptic techniques, ensuring smooth negative pressure drainage, reducing skin flap tension, monitoring skin flap blood supply, actively preventing subcutaneous effusion and hematoma, and applying appropriate compression dressings. Results: The patient was discharged after the removal of the drainage tube. During the postoperative follow-up at 3 and 6 months, there was no recurrence of capsular contracture, and the breast appeared full, upright, and relatively soft. There were no complications such as hematoma, infection, breast implant rupture, breast sagging, or displacement. The patient had a good outcome without additional financial or surgical burdens. Conclusion: The occurrence of Grade IV capsular contracture in the patient is generally related to infection after Stage I expander implantation, improper compression dressing, excessive saline injection causing content infiltration, and radiation therapy. Therefore, it is recommended to enhance the intraoperative and postoperative prophylactic use of antibiotics after Stage I expander implantation. Intermittent saline injection after surgery, with the amount of saline gradually increasing rather than filling all at once, is advisable. This helps the breast tissue gradually adapt to expansion, reducing the risk of capsular contracture. Postoperatively, patients should be instructed to wear pressure garments and breast elastic bandages while intensifying breast monitoring during radiation therapy and increasing postoperative follow-up.

Kinesin 26B modulates M2 polarization of macrophage by activating cancer-associated fibroblasts to aggravate gastric cancer occurrence and metastasis

BACKGROUND The regulatory effects of KIF26B on gastric cancer(GC)have been confirmed,but the specific mechanism still needs further exploration.Pan-cancer analysis shows that the KIF26B expression is highly related to immune infiltration of cancerassociated fibroblasts(CAFs),and CAFs promote macrophage M2 polarization and affect cancers’progression.AIM To investigate the regulatory functions of KIF26B on immune and metastasis of GC.METHODS We analyzed genes’mRNA levels by quantitative real-time polymerase chain reaction.Expression levels of target proteins were detected by immunohistochemistry,ELISA,and Western blotting.We injected AGS cells into nude mice for the establishment of a xenograft tumor model and observed the occurrence and metastasis of GC.The degree of inflammatory infiltration in pulmonary nodes was observed through hematoxylin-eosin staining.Transwell and wound healing assays were performed for the evaluation of cell invasion and migration ability.Tube formation assay was used for detecting angiogenesis.M2-polarized macrophages were estimated by immunofluorescence and flow cytometry.RESULTS KIF26B was significantly overexpressed in cells and tissues of GC,and the higher expression of KIF26B was related to GC metastasis and prognosis.According to in vivo experiments,KIF26B promoted tumor formation and metastasis of GC.KIF26B expression was positively associated with CAFs’degree of infiltration.Moreover,CAFs could regulate M2-type polarization of macrophages,affecting GC cells’migration,angiogenesis,invasion,and epithelial-mesenchymal transition process.CONCLUSION KIF26B regulated M2 polarization of macrophage through activating CAFs,regulating the occurrence and metastasis of GC.

In‑depth proteome characterization of endometrium and extraembryonic membranes during implantation in pig

Background Proteome characterization of the porcine endometrium and extraembryonic membranes is important to understand mother-embryo cross-communication.In this study,the proteome of the endometrium and cho-rioallantoic membrane was characterized in pregnant sows(PS)during early gestation(d 18 and 24 of gestation)and in the endometrium of non-pregnant sows(NPS)during the same days using LC-MS/MS analysis.The UniProtKB database and ClueGO were used to obtain functional Gene Ontology annotations and biological and functional networks,respectively.Results Our analysis yielded 3,254 and 3,457 proteins identified in the endometrium of PS and NPS,respectively;of these,1,753 being common while 1,501 and 1,704 were exclusive to PS and NPS,respectively.In addition,we iden-tified 3,968 proteins in the extraembryonic membranes of PS.Further analyses of function revealed some proteins had relevance for the immune system process and biological adhesion in endometrium while the embryonic chorion displayed abundance of proteins related to cell adhesion and cytoskeletal organization,suggesting they dominated the moment of endometrial remodeling,implantation and adhesion of the lining epithelia.Data are available via Pro-teomeXchange with identifier PXD042565.Conclusion This is the first in-depth proteomic characterization of the endometrium and extraembryonic mem-branes during weeks 3 to 4 of gestation;data that contribute to the molecular understanding of the dynamic environ-ment during this critical period,associated with the majority of pregnancy losses.

Anal metastasis in esophageal cancer:A case report

BACKGROUND Esophageal cancer is the sixth leading cause of cancer-related death and eighth most common cancer,affecting>450000 people worldwide.Esophageal squamous cell carcinoma is the most common histological type,whereas esophageal adenoid cystic carcinoma(EACC)is rare.The liver is the most common distant metastatic site in esophageal cancer.Anal metastasis is rare and has not been reported in clinical practice before.Here,we report anal metastases in a patient with EACC after regular chemotherapy and surgical resection.CASE SUMMARY A 61-year-old esophageal cancer patient was found to have lung and brain metastases during standardized treatment.The patient’s treatment plan was continuously adjusted according to the latest treatment guidelines.However,the patient subsequently noticed rectal bleeding and itching,and after obtaining pathology results at the local hospital,anal metastasis of esophageal cancer was diagnosed.CONCLUSION Postoperative pathology and immunohistochemistry confirmed EACC with rare anal metastasis.More exploration of EACC diagnosis and treatment is needed.

Injectable Nanorobot-Hydrogel Superstructure for Hemostasis and Anticancer Therapy of Spinal Metastasis

Surgery remains the standard treatment for spinal metastasis.However,uncontrolled intraoperative bleeding poses a significant challenge for adequate surgical resection and compromises surgical outcomes.In this study,we develop a thrombin(Thr)-loaded nanorobothydrogel hybrid superstructure by incorporating nanorobots into regenerated silk fibroin nanofibril hydrogels.This superstructure with superior thixotropic properties is injected percutaneously and dispersed into the spinal metastasis of hepatocellular carcinoma(HCC)with easy bleeding characteristics,before spinal surgery in a mouse model.Under near-infrared irradiation,the self-motile nanorobots penetrate into the deep spinal tumor,releasing Thr in a controlled manner.Thr-induced thrombosis effectively blocks the tumor vasculature and reduces bleeding,inhibiting tumor growth and postoperative recurrence with Au nanorod-mediated photothermal therapy.Our minimally invasive treatment platform provides a novel preoperative therapeutic strategy for HCC spinal metastasis effectively controlling intraoperative bleeding and tumor growth,with potentially reduced surgical complications and enhanced operative outcomes.

Microbiota in colorectal cancer related to liver metastasis

The prevalence of colorectal cancer(CRC) is increasing annually and metastasis is the principal cause of death in patients with CRC, with the liver being the most frequently affected site. Many studies have shown a strong interplay between the gut flora, particularly Fusobacterium nucleatum(F. nucleatum), Escherichia coli, and Bacteroides fragilis, and the development of gut tumors. Some strains can induce gut inflammation and produce toxins that directly harm gut epithelial cells, ultimately accelerating the onset and progression of CRC. However,little clinical evidence exists on the specific interplay between the gut microflora and colorectal cancer liver metastasis(CRLM). Some research showed the existence of viable F. nucleatum in distant metastasis of CRC.Subsequently, gut microbiota products, such as lipopolysaccharides, sodium butyrate, and protein cathepsin K, were also found to affect the development of CRC. This article summarizes the mechanism and research status of the interplay between gut microflora and CRLM, discusses the importance of gut microflora in the treatment of CRLM, and proposes a new approach to understanding the mechanism of CRLM and potential treatments for the microbiome. It is anticipated that the gut microbiota will be a formidable therapeutic and prophylactic tool for treating and preventing CRLM.

Resveratrol inhibits pancreatic cancer proliferation and metastasis by depleting senescent tumor-associated fibroblasts

BACKGROUND Pancreatic cancer,a formidable gastrointestinal neoplasm,is characterized by its insidious onset,rapid progression,and resistance to treatment,which often lead to a grim prognosis.While the complex pathogenesis of pancreatic cancer is well recognized,recent attention has focused on the oncogenic roles of senescent tumor-associated fibroblasts.However,their precise role in pancreatic cancer remains unknown.Resveratrol is a natural polyphenol known for its multifaceted biological actions,including antioxidative and neuroprotective properties,as well as its potential to inhibit tumor proliferation and migration.Our current investigation builds on prior research and reveals the remarkable ability of resveratrol to inhibit pancreatic cancer proliferation and metastasis.AIM To explore the potential of resveratrol in inhibiting pancreatic cancer by targeting senescent tumor-associated fibroblasts.METHODS Immunofluorescence staining of pancreatic cancer tissues revealed prominent coexpression ofα-SMA and p16.HP-1 expression was determined using immunohistochemistry.Cells were treated with the senescence-inducing factors known as 3CKs.Long-term growth assays confirmed that 3CKs significantly decreased the CAF growth rate.Western blotting was conducted to assess the expression levels of p16 and p21.Immunofluorescence was performed to assess LaminB1 expression.Quantitative real-time polymerase chain reaction was used to measure the levels of several senescence-associated secretory phenotype factors,including IL-4,IL-6,IL-8,IL-13,MMP-2,MMP-9,CXCL1,and CXCL12.A scratch assay was used to assess the migratory capacity of the cells,whereas Transwell assays were used to evaluate their invasive potential.RESULTS Specifically,we identified the presence of senescent tumor-associated fibroblasts within pancreatic cancer tissues,linking their abundance to cancer progression.Intriguingly,Resveratrol effectively eradicated these fibroblasts and hindered their senescence,which consequently impeded pancreatic cancer progression.CONCLUSION This groundbreaking discovery reinforces Resveratrol's stature as a potential antitumor agent and positions senescent tumor-associated fibroblasts as pivotal contenders in future therapeutic strategies against pancreatic cancer.

Game-changing insights on vertebral skeletal stem cells in bone metastasis and therapeutic horizons

Greenblatt and his team have unveiled vertebral skeletal stem cells(vSSCs)as a critical player in the landscape of bone metastasis.This commentary delves into the transformative discoveries surrounding vSSCs,emphasizing their distinct role in bone metastasis compared to other stem cell lineages.We illuminate the unique properties and functions of vSSCs,which may account for the elevated susceptibility of vertebral bones to metastatic invasion.Furthermore,we explore the exciting therapeutic horizons opened by this newfound understanding.These include potential interventions targeting vSSCs,modulation of associated signaling pathways,and broader implications for the treatment and management of bone metastasis.By shedding light on these game-changing insights,we hope to pave the way for novel strategies that could revolutionize the prognosis and treatment landscape for cancer patients with metastatic bone disease.

Clinical prediction of insufficient vaults after implantable collamer lens implantation

AIM:To determine the factors related to preoperative ocular characters that are predictive of insufficient vault(<250μm)after implantable collamer lens(ICL V4c;STAAR Surgical)implantation.METHODS:The participants underwent ICL surgery and were divided into the low(<250μm)and normal(250-1000μm)vault groups based on the postoperative vault at 3mo.The preoperative biometric parameters and clinical outcomes were compared between the two groups.The relationship between the 3-month vault values and preoperative ocular parameters were evaluated by Generalized estimating equations.RESULTS:Sixteen(23 eyes)and 36 patients(63 eyes)were in the low and normal vault groups,respectively.All implantation procedures were uneventful with no cataract formation in the early postoperative period.The sulcusto-sulcus lens rise(STSL)and iris ciliary angle(ICA)were correlated with vault at 3mo after surgery.Every 0.1 mm increase in STSL was associated with 38.9μm decrease in the postoperative 3-month vault.A rise of 1 degree in ICA is associated with a reduction of 4μm in vault.CONCLUSION:Eyes with a narrow ciliary sulcus are associated with a higher rate of low vault after ICL implantation,suggesting a need for adjustments to the ICL size in these patients.Evaluating the characteristics of the ciliary sulcus contributes valuable information to predict low vault after surgery.

Chemoradiotherapy plus tislelizumab for mismatch repair proficient rectal cancer with supraclavicular lymph node metastasis:A case report

BACKGROUND According to the latest report,colorectal cancer is still one of the most prevalent cancers,with the third highest incidence and mortality worldwide.Treatment of advanced rectal cancer with distant metastases is usually unsatisfactory,especially for mismatch repair proficient(pMMR)rectal cancer,which leads to poor prognosis and recurrence.CASE SUMMARY We report a case of a pMMR rectal adenocarcinoma with metastases of multiple lymph nodes,including the left supraclavicular lymph node,before treatment in a 70-year-old man.He received full courses of chemoradiotherapy(CRT)followed by 4 cycles of programmed death 1 inhibitor Tislelizumab,and a pathologic complete response(pCR)was achieved,and the lesion of the left supraclavicular lymph node also disappeared.CONCLUSION pMMR advanced rectal cancer with preserved intact distant metastatic lymph nodes may benefit from full-course CRT combined with immunotherapy.

NUDT5 promotes the growth,metastasis,and Warburg effect of IDH wild-type glioblastoma multiforme cells by upregulating TRIM47

Objective:To explore the regulatory mechanism of NUDT5 in glioblastoma multiforme(GBM).Methods:GEPIA database was used to predict the expressions of NUDT5 and tripartite motif family proteins 47(TRIM47)in GBM patients.RT-qPCR and Western blot analyses were performed to examine NUDT5 expression in GBM cells.LN-229 cell proliferation,migration as well as invasion were estimated by CCK-8,colony formation,wound healing,and Transwell assays following interference with NUDT5.ECAR assay,L-lactic acid kit,glucose detection kit,and ATP detection kit were applied for the detection of glycolysis-related indexes.Co-immunoprecipitation experiment was carried out to verify the relationship between NUDT5 and TRIM47.Results:GEPIA database showed that NUDT5 expression was significantly increased in GBM patients.Inhibiting the expression of NUDT5 in GBM cells significantly suppressed the viability,proliferation,invasion,migration,and glycolysis of GBM cells.Moreover,TRIM47 was highly expressed in GBM cells and interacted with NUDT5.Overexpression of TRIM47 partially reversed the inhibitory effect of NUDT5 downregulation on the proliferation,metastasis,and glycolysis of GBM cells.Conclusions:NUDT5 promotes the growth,metastasis,and Warburg effect of GBM cells by upregulating TRIM47.Both NUDT5 and TRIM47 can be used as targets for GMB treatment.

Shedding light on pancreatic metastasis of clear cell sarcoma:An exceptional journey

This editorial comments on the study by Liu et al investigating pancreatic metastasis of clear cell sarcoma(CCS)published in the World Journal of Clinical Cases.CCS is a rare and aggressive melanocytic tumor,that typically arises from tendons and aponeuroses of the limbs,and metastasizes to the lungs,bones,and brain.However,pancreatic metastasis has rarely been reported,presenting unique diagnostic and therapeutic challenges.Elucidating the clinical characteristics,imaging features,prognostic factors,and treatment outcomes of patients with pancreatic CCS metastasis is crucial.Surgery remains an effective management strategy for CCS.However,the high recurrence rate and low effectiveness of traditional adjuvant treatments necessitate a shift towards more personalized and targeted treatment plans.Research is needed to investigate and validate novel therapeutic approaches specifically tailored to the distinct genetic and molecular characteristics of rare malignancies like CCS.Additionally,the development of late metastases after a long disease-free interval is common in CCS patients.Therefore,routine postoperative surveillance for metastasis using computed tomography,magnetic resonance imaging,bone scans,and positron emission tomography scans is crucial.Moving forward,enhanced collaboration,investigation,and creative thinking among scientists,medical professionals,and legislators are essential to gain a deeper understanding of these rare presentations.

MicroRNAs:A novel signature in the metastasis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma(ESCC)is a malignant epithelial tumor,characterized by squamous cell differentiation,it is the sixth leading cause of cancer-related deaths globally.The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered,coupled with higher risk of metastasis,which is an exceedingly malignant charac-teristic of cancer,frequently leading to a high mortality rate.Unfortunately,there is currently no specific and effective marker to predict and treat metastasis in ESCC.MicroRNAs(miRNAs)are a class of small non-coding RNA molecules,approximately 22 nucleotides in length.miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence,progression,and prognosis of cancer.Here,we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis,and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors.This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis,with the ultimate aim of reducing the mortality rate among patients with ESCC.

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.