Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

BACKGROUND Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as well.However,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure.AIM This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and recurrence.METHODS The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled.Clinical data were compared according to anti-TNF therapy and CPF closure.RESULTS A total of 65 patients were included.The median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)patients.The closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for closure.The cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,respectively.CONCLUSION Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation.However,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy.Fistulous tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

Controversies regarding transplantation of mesenchymal stem cells

Mesenchymal stem cells(MSCs)have tantalized regenerative medicine with their therapeutic potential,yet a cloud of controversies looms over their clinical tran-splantation.This comprehensive review navigates the intricate landscape of MSC controversies,drawing upon 15 years of clinical experience and research.We delve into the fundamental properties of MSCs,exploring their unique immuno-modulatory capabilities and surface markers.The heart of our inquiry lies in the controversial applications of MSC transplantation,including the perennial debate between autologous and allogeneic sources,concerns about efficacy,and lingering safety apprehensions.Moreover,we unravel the enigmatic mechanisms surro-unding MSC transplantation,such as homing,integration,and the delicate balance between differentiation and paracrine effects.We also assess the current status of clinical trials and the ever-evolving regulatory landscape.As we peer into the future,we examine emerging trends,envisioning personalized medicine and innovative delivery methods.Our review provides a balanced and informed perspective on the controversies,offering readers a clear understanding of the complexities,challenges,and potential solutions in MSC transplantation.

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.

Interferon-gamma and tumor necrosis factor-alpha synergistically enhance the immunosuppressive capacity of human umbilical-cordderived mesenchymal stem cells by increasing PD-L1 expression

BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune diseases.In MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is unclear.AIM To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative colitis.METHODS We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in combination.Additionally,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 expression.Moreover,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene promoters.Finally,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute colitis.RESULTS Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of PD-L1.IFN-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 mRNA.Although TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 activation.TNF-αupregulated IFN-γreceptor expression through activation of the nuclear factor kappa-B signaling pathway,which significantly enhanced IFN-γsignaling.Finally,co-induced hUC-MSCs have a stronger inhibitory effect on lymphocyte proliferation,and significantly ameliorate weight loss,mucosal damage,inflammatory cell infiltration,and up-regulation of inflammatory factors in colitis mice.CONCLUSION Overall,our results suggest that IFN-γand TNF-αenhance both the immunosuppressive ability of hUC-MSCs and their efficacy in ulcerative colitis by synergistically inducing high expression of PD-L1.

MIR-448 Regulates MAGEA6/AMPK Signaling Pathway in Hepatocellular Carcinoma Tumor Stem Cells

Objective: To explore the role of miR-448 in regulating MAGEA6/AMPK signaling pathway in the biological study of hepatocellular carcinoma (HCC) tumor stem cells. Methods: Using the database, the hepatocellular carcinoma related expression chips were obtained and the regulatory mirnas of candidate genes were predicted, and the predicted results were analyzed. The effects of miR-448 and MAGEA6 on the pellet formation rate and clone formation rate of hepatocellular carcinoma stem cells were detected by immunofluorescence identification of stem cell markers and light microscope counting method. The effects of miR-448 and MAGEA6 on migration and invasion of hepatocellular carcinoma stem cells were detected by scratch and Transwell assay. Dual luciferase reporter assay to verify whether miR-448 targets MAGEA6. The expression and influence of miR-448 on MAGEA6 and AMPK pathway were detected by qRT-PCR and Western blot. Results: It was found that miR-448 may directly regulate the expression of MAGEA6. Overexpression of miR-448 inhibited the characteristics, proliferation, migration, and invasion of hepatocellular carcinoma stem cells in vitro, as well as the ability of xenograft tumor formation in vivo. However, inhibition of miR-448 showed opposite results. In addition, miR-448 directly targets MAGEA6 and regulates AMPK signaling. Silencing MAGEA6 and adding AMPK activator further verified that miR-448 activated AMPK signaling pathway by targeting MAGEA6, thus affecting characteristics, proliferation, migration and invasion of hepatoma stem cells. Conclusions: Our results reveal that miR-448 activates AMPK signaling pathway by targeting MAGEA6, thereby affecting characteristics, proliferation, migration and invasion of hepatoma stem cells. It is suggested that overexpression of miR-448 may be a new therapeutic strategy for hepatocellular carcinoma.

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.

Etanercept-synthesizing adipose-derived stem cell secretome:A promising therapeutic option for inflammatory bowel disease

BACKGROUND Inflammatory bowel disease(IBD)is a chronic inflammatory condition of the gastrointestinal tract,with tumor necrosis factor(TNF)-αplaying a key role in its pathogenesis.Etanercept,a decoy receptor for TNF,is used to treat inflammatory conditions.The secretome derived from adipose-derived stem cells(ASCs)has anti-inflammatory effects,making it a promising therapeutic option for IBD.AIM To investigate the anti-inflammatory effects of the secretome obtained from ASCs synthesizing etanercept on colon cells and in a dextran sulfate sodium(DSS)-induced IBD mouse model.METHODS ASCs were transfected with etanercept-encoding mini-circle plasmids to create etanercept-producing cells.The secretory material from these cells was then tested for anti-inflammatory effects both in vitro and in a DSS-induced IBD mouse model.RESULTS This study revealed promising results indicating that the group treated with the secretome derived from etanercept-synthesizing ASCs[Etanercept-Secretome(Et-Sec)group]had significantly lower expression levels of inflammatory mediators,such as interleukin-6,Monocyte Chemoattractant Protein-1,and TNF-α,when compared to the control secretome(Ct-Sec).Moreover,the Et-Sec group exhibited a marked therapeutic effect in terms of preserving the architecture of intestinal tissue compared to the Ct-Sec.CONCLUSION These results suggest that the secretome derived from ASCs that synthesize etanercept has potential as a therapeutic agent for the treatment of IBD,potentially enhancing treatment efficacy by merging the anti-inflam-matory qualities of the ASC secretome with etanercept's targeted approach to better address the multifaceted pathophysiology of IBD.

Therapeutic implications of cancer stem cells in prostate cancer

Prostate cancer, one of the most frequently occurring cancers in men, is a heterogeneous disease involving multiple cell types within tumors. This tumor heterogeneity at least partly results from genomic instability leading to sub-clonal cellular differentiation. The differentiated cell populations originate from a small subset of cells with tumor-initiating and stem-like properties. These cells, termed prostate cancer stem cells(PCSCs), play crucial roles in disease progression, drug resistance, and relapse. This review discusses the origin, hierarchy, and plasticity of PCSCs;methods for isolation and enrichment of PCSCs;and various cellular and metabolic signaling pathways involved in PCSC induction and maintenance, as well as therapeutic targeting.

Targeting the mechano-microenvironment and liver cancer stem cells:a promising therapeutic strategy for liver cancer

Over the past 2 decades,cancer stem cells(CSCs)have been identified as the root cause of cancer occurrence,progression,chemoradioresistance,recurrence,and metastasis.Targeting CSCs is a novel therapeutic strategy for cancer management and treatment.Liver cancer(LC)is a malignant disease that can endanger human health.Studies are increasingly suggesting that changes in the liver mechanical microenvironment are a primary driver triggering the occurrence and development of liver cancer.In this review,we summarize current understanding of the roles of the liver mechano-microenvironment and liver cancer stem cells(LCSCs)in liver cancer progression.We also discuss the relationship between the mechanical heterogeneity of liver cancer tissues and LCSC recruitment and metastasis.Finally,we highlight potential mechanosensitive molecules in LCSCs and mechanotherapy in liver cancer.Understanding the roles and regulatory mechanisms of the mechano-microenvironment and LCSCs may provide fundamental insights into liver cancer progression and aid in further development of novel therapeutic strategies.

Circulating tumor and cancer stem cells in hepatitis C virusassociated liver disease

AIM:To assess the role of circulating tumor cells(CTCs)and cancer stem cells(CSCs)in hepatitis C virus(HCV)-associated liver disease.METHODS:Blood and/or tissue samples were obtained from HCV(genotype 4)-associated hepatocellularcarcinoma patients(HCC;n=120),chronic hepatitis C patients(CH;n=30)and 33 normal control subjects(n=33).Serum levels of alpha-fetoprotein(AFP),alkaline phosphatase,and alanine and aspartate aminotransferases were measured.Cytokeratin 19(CK19)monoclonal antibody was used to enumerate CTCs,and CD133 and CD90 were used to enumerate CSCs by flow cytometry.The expression levels of the CSCs markers(CD133 and CD90)as well as telomerase,melanoma antigen encoding gene 1(MAGE1)and MAGE3 were assessed by RTPCR and quantitative real-time polymerase chain reactions.The number of CTCs and/or the expression levels of CK19,CD133,telomerase,MAGE1 and MAGE3 were correlated to the standard clinicopathologic prognostic factors and disease progression.RESULTS:Levels of AFP,alkaline phosphatase and aspartate aminotransferase were significantly different among the HCC,CH and control groups(P<0.001),whereas alanine aminotransferase differed significantly between patient(HCC and CH)and control groups(P<0.001).At the specified cutoff values determine by flow cytometry,CK19(49.8),CD90(400)and CD133(73)were significantly higher in the blood of HCC patients compared to those in the CH and control groups(P<0.001).On the other hand,CD133 at a 69.5 cutoff was significantly higher in the CH compared to the control group(P≤0.001).Telomerase,MAGE1 and MAGE3RNA were expressed in 55.71%,60.00%and 62.86%of the HCC patients,respectively,but were not detected in patients in the CH or control groups,which were statistically significant(Ps<0.001).The expression levels of telomerase,CD90,MAGE3,CD133 and CK19 were all significantly associated with high tumor grade and advanced stage in HCC patients(all P s<0.05).CONCLUSION:CTC counts and AFP,CK19,telomerase,and MAGE1/MAGE3 expression predict disease progression in patients with HCV,whereas telomerase,MAGE3,CD90,CD133 and CK19 are prognostic mark-

Differentiation profile of brain tumor stem cells:a comparative study with neural stem cells

大脑肿瘤干细胞(BTSC ) 的区别侧面的理解，在肿瘤房间人口之中的关键的，将通过有神经干细胞(NSC ) 的比较借卓见进 glioma 的起源并且最终产出新途径与这难处理的疾病作斗争。这里，我们从外科的 glioma 标本的有教养、净化的 BTSC 和 NSCsfrom 人的胎儿的大脑织物，并且进一步分析了他们的细胞的生物行为，他们的特别区别性质。是期望，区分进成熟神经显型的 NSC。然而， BTSC 展出了的 Inthe 一样的区别状况区分了差别。词法上，房间变得变平并且属于第一个星期，但是逐渐地此后聚集了并且改过漂浮的肿瘤范围。在相应时期期间，无差别的房间标记 CD133 和巢在的表示率在 BTSC 不停地减少，但是 1 个星期以后，他们重获上升趋势。有趣地，区分的房间标记 GFAP 和 beta-tubulinIIIshowed 表示变化逆到无差别的房间标记的。总起来说， BTSCswere 揭示了拥有一个能力抵抗区别，它实际上代表 glioma 的恶意的行为。

Isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma

AIM: To explore the method of isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma cell line PANC-1. METHODS: The PANC-1 cells were cultured in Dulbecco modified eagle medium F12 (1:1 volume) (DMEM-F12) supplemented with 20% fetal bovine serum (FBS). Subpopulation cells with properties of tumor stem cells were isolated from pancreatic adenocarcinoma cell line PANC-1 according to the cell surface markers CD44 and CD24 by flow cytometry. The proliferative capability of these cells in vitro were estimated by 3-[4,5-dimehyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium bromide (MTT) method. And the tumor growth of different subpopulation cells which were injected into the hypodermisof right and left armpit of nude mice was studied,and expression of CD44 and CD24 of the CD44+CD24+ cell-formed nodules and PANC-1 cells were detected by avidin-biotin-peroxidase complex (ABC) immunohistochemical staining. RESULTS: The 5.1%-17.5% of sorted PANC-1 cells expressed the cell surface marker CD44,57.8% -70.1% expressed CD24,only 2.1%-3.5% of cells were CD44+ CD24+. Compared with CD44-CD24-cells,CD44+CD24+ cells had a lower growth rate in vitro. Implantation of 104 CD44-CD24-cells in nude mice showed no evidenttumor growth at wk 12. In contrast,large tumors were found in nude mice implanted with 103 CD44+CD24+ cells at wk 4 (2/8),a 20-fold increase in tumorigenic potential (P < 0.05 or P < 0.01). There was no obvious histological difference between the cells of the CD44+CD24+ cell-formed nodules and PANC-1 cells. CONCLUSION: CD44 and CD24 may be used as the cell surface markers for isolation of pancreatic cancer stem cells from pancreatic adenocarcinoma cell line PANC-1. Subpopulation cells CD44+CD24+ have properties of tumor stem cells. Because cancer stem cells are thought to be responsible for tumor initiation and its recurrence after an initial response to chemotherapy,it may be a very promising target for new drug development.

Similarity on neural stem cells and brain tumor stem cells in transgenic brain tumor mouse models

Although it is believed that glioma is derived from brain tumor stem cells, the source and molecular signal pathways of these cells are still unclear. In this study, we used stable doxycycline-inducible transgenic mouse brain tumor models （c-myc/SV40Tag＋/Tet-on＋） to explore the malignant trans- formation potential of neural stem cells by observing the differences of neural stem cells and brain tumor stem cells in the tumor models. Results showed that chromosome instability occurred in brain tumor stem cells. The numbers of cytolysosomes and autophagosomes in brain tumor stem cells and induced neural stem cells were lower and the proliferative activity was obviously stronger than that in normal neural stem cells. Normal neural stem cells could differentiate into glial fibrillary acidic protein-positive and microtubule associated protein-2-positive cells, which were also negative for nestin. However, glial fibrillary acidic protein/nestin, microtubule associated protein-2/nestin, and glial fibrillary acidic protein/microtubule associated protein-2 double-positive cells were found in induced neural stem cells and brain tumor stem cells. Results indicate that induced neural stem cells are similar to brain tumor stem cells, and are possibly the source of brain tumor stem cells.

An overview of the role of cancer stem cells in spine tumors with a special focus on chordoma

Primary malignant tumors of the spine are relatively rare, less than 5% of all spinal column tumors. However, these lesions are often among the most difficult to treat and encompass challenging pathologies such as chordoma and a variety of invasive sarcomas. The mechanisms of tumor recurrence after surgical intervention, as well as resistance to radiation and chemotherapy, remain a pervasive and costly problem. Recent evidence has emerged supporting the hypothesis that solid tumors contain a sub-population of cancer cells that possess characteristics normally associated with stem cells. Particularly, the potential for long-term proliferation appears to be restricted to subpopulations of cancer stem cells(CSCs) functionally defined by their capacity to self-renew and give rise to differentiated cells that phenotypically recapitulate the original tumor, thereby causing relapse and patient death. These cancer stem cells present a unique opportunity to better understand the biology of solid tumors in general, as well as targets for future therapeutics. The general objective of the current study is to discuss the fundamental concepts for understanding the role of CSCs with respect to chemoresistance, radioresistance, special cell surface markers, cancer recurrence and metastasis intumors of the osseous spine. This discussion is followed by a specific review of what is known about the role of CSCs in chordoma, the most common primary malignant osseous tumor of the spine.

Reversing multiple age-related pathologies by controlling the senescence-associated secretory phenotype of stem cells

Regenerative medicine by cell transplantation is a novel therapy for treating end-stage organ failure and tissue damage. Cell-based therapy based on the transplantation of neural stem/progenitor cells （NSPCs） represents an attractive strategy for the treatment of neurodegenerative diseases, but obtaining large numbers of these cells is difficult and their differentiation potential is strictly restricted in a spatiotemporally-regulated manner during central nervous system （CNS） development. Therefore, embryonic stem cells and induced pluripotent stem cells represent an attractive alternative for cell-transplantation therapy in regenerative medicine.

The cultivation and identification of tumor stem cells from neuroblastoma derived tumor spheres

Background and Objective: Since the proposal of the tumor stem cell hypothesis, considerable interest has been devoted to the isolation and purification of tumor stem cells. Tumor stem cell enrichment from primary tumor derived cell spheres has been demonstrated in specific, serum-free media. This goal of this study is to establish a method of cultivating floating tumor spheres from neuroblastoma cells and to confirm that neuroblastoma spheres are rich in tumor stem cells. Methods: Bone marrow aspirates were obtained from pediatric patients diagnosed with stage IV neuroblastoma. Primary tumor cells were isolated and cultivated in serum-free, stem cell-selective medium. Single sphere-forming cells were cultivated under serum-free conditions; their cloning efficiency and monoclonal tumor sphere formation rates were calculated. The expression of stem cell marker genes Oct-4 and Bmi-1 was detected by RT-PCR in sphere-forming cells and parental neurolastoma cells. Sphere-forming cells were injected into the armpit of nude mice with subsequent assessment for tumor growth. Sphere-forming cells were cultivated in differentiation medium containing 5 μmol/L 13-cis retinoic acid; changes in cell morphology were observed. Results: Neuroblastoma cells formed non-adherent neurospheres under serum-free, stem cell-selective conditions after a period of 4 to 6 days. A single cell dissociated from a neurosphere could reform a monoclonal sphere; cloning efficiency and monoclonal sphere formation rates were 55.3% and 26.3%, respectively. RT-PCR results revealed heightened tumor sphere expression of Oct-4 and Bmi-1 as compared with parental tumor cells. Fourteen days after injection of 104 sphere-forming cells into nude mice, a neuroblastoma xenograft formed. Treatment of sphere-forming cells with 13-cis retinoic acid induced a gradual differentiation to neuronal cell morphology. Conclusions: Neuroblastoma derived tumor spheres enrich tumor stem cells and the cultivation of primary neuroblastoma cells in serum-free, stem cell-selective medium is an effective method to dissociate and purify tumor stem cells in vitro.

Research Progress in the Regulation of Tumor Cells and Tumor Stem Cells at Multiple Targets by Antrodia camphorata

Extensive in vitro and in vivo research reveals multiple intracellular molecular targets of Antrodia camphorata,and these targets affect growth,apoptosis,angiogenesis,invasion and metastasis of cells.These targets include tumor suppressor,cell cycle regulator,transcription factor,angiogenesis and metastasis factor,apoptosis and survival regulator,etc.Additionally,more and more attention has been paid to the molecular mechanism of A.camphorata on the regulation of tumor stem cells.Meanwhile,there is evidence that the immunoregulation of A.camphorata is enhanced,which may lead cell cycle arrest or apoptosis.In this paper,molecular mechanism of tumor cells and tumor stem cells regulated at multiple targets by A.camphorata in vitro and in vivo in the past decade is summarized.

Xiaotan Sanjie decoction attenuates tumor angiogenesis by manipulating Notch-1-regulated proliferation of gastric cancer stem-like cells

AIM: To determine the underlying mechanisms of action and influence of Xiaotan Sanjie(XTSJ) decoction on gastric cancer stem-like cells(GCSCs). METHODS: The gastric cancer cell line MKN-45 line was selected and sorted by FACS using the cancer stem cell marker CD44; the stemness of these cells was checked in our previous study. In an in vitro study, the expression of Notch-1, Hes1, Vascular endothelial growth factor(VEGF), and Ki-67 in both CD44-positive gastric cancer stem-like cells(GCSCs) and CD44-negative cells was measured by Western blot. The effect of XTSJ serum on cell viability and on the above markers was measured by MTT assay and Western blot, respectively. In an in vivo study, the ability to induce angiogenesis and maintenance of GCSCs in CD44-positive-MKN-45- and CD44-negative-engrafted mice were detected by immunohistochemical staining using markers for CD34 and CD44, respectively. The role of XTSJ decoction in regulating the expression of Notch-1, Hes1, VEGF and Ki-67 was measured by Western blot and real-time polymerase chain reaction.RESULTS: CD44+ GCSCs showed more cell proliferation and VEGF secretion than CD44-negative cells in vitro, which were accompanied by the high expression of Notch-1 and Hes1 and positively associated with tumor growth(GCSCs vs CD44-negative cells, 2.72 ± 0.25 vs 1.46 ± 0.16, P < 0.05) and microvessel density(MVD)(GCSCs vs CD44-negative cells, 8.15 ± 0.42 vs 3.83 ± 0.49, P < 0.001) in vivo. XTSJ decoction inhibited the viability of both cell types in a dose-dependent manner in vitro. Specifically, a significant difference in the medium-(82.87% ± 6.53%) and high-dose XTSJ groups(77.43% ± 7.34%) was detected at 24 h in the CD44+ GCSCs group compared with the saline group(95.42% ± 5.76%) and the low-dose XTSJ group(90.74% ± 6.57%)(P < 0.05). However, the efficacy of XTSJ decoction was reduced in the CD44- groups; significant differences were only detected in the high-dose XTSJ group at 48 h(78.57% ± 6.94%) and 72 h(72.12% ± 7.68%) when compared with the other CD44- groups(P < 0.05). Notably, these differences were highly consistent with the Notch-1, Hes1, VEGF and Ki-67 expression in these cells. Similarly, in vivo, XTSJ decoction inhibited tumor growth in a dose-dependent manner. A significant difference was observed in the medium(1.76 ± 0.15) and high-dose XTSJ(1.33 ± 0.081) groups compared with the GCSCs control group(2.72 ± 0.25) and the low-dose XTSJ group(2.51 ± 0.25)(P < 0.05). We also detected a remarkable decrease of MVD in the medium-(7.10 ± 0.60) and high-dose XTSJ(5.99 ± 0.47) groups compared with the GCSC control group(8.15 ± 0.42) and the low-dose XTSJ group(8.14 ± 0.46)(P < 0.05). Additionally, CD44 expression was decreased in these groups [medium-(4.43 ± 0.45) and high-dose XTSJ groups(3.56 ± 0.31) vs the GCSC control(5.96 ± 0.46) and low dose XTSJ groups(5.91 ± 0.38)](P < 0.05). The significant differences in Notch-1, Hes1, VEGF and Ki-67 expression highly mirrored the results of XTSJ decoction in inhibiting tumor growth, MVD and CD44 expression.CONCLUSION: Notch-1 may play an important role in regulating the proliferation of GCSCs; XTSJ decoction could attenuate tumor angiogenesis, at least partially, by inhibiting Notch-1.

Single-cell analysis of tumors:Creating new value for molecular biomarker discovery of cancer stem cells and tumor-infiltrating immune cells

Biomarker-driven individualized treatment in oncology has made tremendous progress through technological developments, new therapeutic modalities and a deeper understanding of the molecular biology for tumors, cancer stem cells and tumor-infiltrating immune cells. Recent technical developments have led to the establishment of a variety of cancer-related diagnostic, prognostic and predictive biomarkers. In this regard, different modern OMICs approaches were assessed in order to categorize and classify prognostically different forms of neoplasia. Despite those technical advancements, the extent of molecular heterogeneity at the individual cell level in human tumors remains largely uncharacterized. Each tumor consists of a mixture of heterogeneous cell types. Therefore, it is important to quantify the dynamic cellular variations in order to predict clinical parameters, such as a response to treatment and or potential for disease recurrence. Recently, single-cell based methods have been developed to characterize the heterogeneity in seemingly homogenous cancer cell populations prior to and during treatment. In this review, we highlight the recent advances for single-cell analysis and discuss the challenges and prospects for molecular characterization of cancer cells, cancer stem cells and tumor-infiltrating immune cells.

Training stem cells for treatment of malignant brain tumors

The treatment of malignant brain tumors remains a challenge. Stem cell technology has been applied in the treatment of brain tumors largely because of the ability of some stem cells to infiltrate into regions within the brain where tumor cells migrate as shown in preclinical studies. However, not all of these efforts can translate in the effective treatment that improves the quality of life for pa-tients. Here, we perform a literature review to identify the problems in the field. Given the lack of efficacy of most stem cell-based agents used in the treatment of malignant brain tumors, we found that stem cell distribution(i.e., only a fraction of stem cells applied capable of targeting tumors) are among the limiting factors. We provide guidelines for potential improvements in stem cell distribution. Specifically, we use an engineered tissue graft platform that replicates the in vivo microenvironment, and provide our data to validate that this culture platform is viable for producing stem cells that have better stem cell distribution than with the Petri dish culture system.