CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

BACKGROUND CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors,including gastric cancer(GC),and is associated with tumor progression and immune infiltration;however,the roles and mechanisms of CALD1 in epithe-lial-mesenchymal transition(EMT)in GC are unknown.AIM To investigate the role and mechanism of CALD1 in GC progression,invasion,and migration.METHODS In this study,the relationship between CALD1 and GC,as well as the possible network regulatory mechanisms of CALD1,was investigated by bioinformatics and validated by experiments.CALD1-siRNA was synthesized and used to trans-fect GC cells.Cell activity was measured using the CCK-8 method,cell migration and invasive ability were measured using wound healing assay and Transwell assay,and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot.A GC cell xenograft model RESULTS Bioinformatics results showed that CALD1 was highly expressed in GC tissues,and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC.The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression,and a prognostic model was constructed and evaluated.The experimental results were consistent with the results of the bioinformatics analysis.The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1,with the strongest expression found in AGS and MKN45 cells.Cell activity was significantly reduced after CALD1-siRNA trans-fection of AGS and MKN45 cells.The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection,and the related mRNA and protein expression was altered.According to bioinfor-matics findings in GC samples,the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway,and was closely related to the PI3K-Akt signaling pathway.Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K,p-AKT,and p-mTOR,members of the PI3K-Akt pathway,while decreasing the expression of PTEN;PI3K-Akt inhibitor treatment decreased the expression of PI3K,p-AKT,and p-mTOR in cells overexpressing CALD1(still higher than that in the normal group),but increased the expression of PTEN(still lower than that in the normal group).CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor.Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor.The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1,whereas the effect of overex-pression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor.Animal experiments showed that tumour growth was slow after inhibition of CALD1,and the expression of some PI3K-Akt and EMT pathway proteins was altered.CONCLUSION Increased expression of CALD1 is a key factor in the progression,invasion,and metastasis of GC,which may be associated with regulating the PI3K-Akt pathway to promote EMT.

Epithelial-mesenchymal transition contributes to malignant phenotypes of circulating tumor cells derived from gastric cancer

Circulating tumor cells(CTCs)are crucial to tumor metastasis,and they usually undergo epithelial-mesenchymal transition(EMT)in order to disseminate from the primary tumor.However,very little is currently known about the relationship between EMT and malignant phenotypes of CTCs in the context of gastric cancer.Therefore,this study aimed to investigate the contribution of EMT to malignant phenotypes of CTCs derived from gastric cancer cells.We xenografted MKN28 gastric cancer cells pretreated with transforming growth factor-beta 1(TGFβ-1)into nude mice by intravenous injection.Next,we isolated CTCs from the blood of nude mice by gradient centrifugation and found that CTCs derived from MKN28 cells pretreated with TGFβ-1 had a significantly increased viability and invasion ability compared to MKN28 cells without TGFβ-1 treatment.Immunocytochemical staining showed lower expression of E-cadherin and higher expression of N-cadherin,vimentin,and β-catenin in CTCs derived from MKN28 cells pretreated with TGFβ-1.Furthermore,the expression of Wnt3a,β-catenin,cyclin D1,and c-Myc was significantly higher in CTCs derived from MKN28 cells pretreated with TGFβ-1.Taken together,these findings suggest that TGFβ promotes EMT and malignant phenotypes of gastric cancer cells.Furthermore,the malignant phenotypes of gastric cancer cells induced by TGFβ are maintained in CTCs derived from these cells.Targeting EMT in CTCs is a new approach to the treatment of gastric cancer relapse and metastasis.

Role of epithelial-mesenchymal transition in gastric cancer initiation and progression

Gastric cancer is one of the most common malignant tumors worldwide.Due to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to achieve.The epithelial-mesenchymal transition(EMT)is characterized as a fundamental process that is critical for embryonic development,wound healing and fibrotic disease.Recent evidence has established that aberrant EMT activation in the human stomach is closely associated with gastric carcinogenesis and tumor progression.EMT activation endows gastric epithelial cells with increased characteristics of mesenchymal cells and reduces their epithelial features.Moreover,mesenchymal cells tend to dedifferentiate and acquire stem cell or tumorigenic phenotypes such as invasion,metastasis and apoptosis resistance as well as drug resistance during EMT progression.There are a number of molecules that indicate the stage of EMT(e.g.,E-cadherin,an epithelial cell biomarker);therefore,certain transcriptional proteins,especially E-cadherin transcriptional repressors,may participate in the regulation of EMT.In addition,EMT regulation may be associated with certain epigenetic mechanisms.The aforementioned molecules can be used as early diagnostic markers for gastric cancer,and EMT regulation can provide potential targets for gastric cancer therapy.Here,we review the role of these aspects of EMT in gastric cancer initiation and development.

Crosstalk between tumor cells and microenvironment via Wnt pathway in colorectal cancer dissemination

Invasion and metastasis are the deadly face of malignant tumors. Considering the high rate of incidence and mortality of colorectal cancer, it is critical to determine the mechanisms of its dissemination. In the parallel investigation of the invasive front and tumor center area of colorectal cancer (CRC), observation of heterogeneous β-catenin distribution and epithelial-mesenchymal transition (EMT) at the invasive front suggested that there might be a crosstalk between tumor cells and the tumor microenvironment. Wnt signaling pathway is also involved in the cancer progression due to its key role in CRC tumorigenesis. Moreover, in recent years, there is increasing evidence that the regulators of microenvironment, including extracellular matrix, growth factors and inflammatory factors, are associated with the activation of Wnt pathway and the mobility of tumor cells. In this review, we will try to explain how these molecules trigger metastasis via the Wnt pathway.

27-Hydroxycholesterol-induced EndMT acts via STAT3 signaling to promote breast cancer cell migration by altering the tumor microenvironment

Objective:The endothelial to mesenchymal transition(EndMT)plays a major role in cancer metastasis by regulating the complexity of the tumor microenvironment(TME).Here,we investigated whether 27-hydroxycholesterol(27 HC)induces EndMT in endothelial cells(ECs).Methods:EndMT markers in the human microvascular endothelial cell-1(HMEC-1)cell line and human umbilical vein endothelial cells(HUVECs)stimulated with 27 HC were evaluated with Western blot.Epithelial to mesenchymal transition(EMT)markers in breast cancer(BC)cells cultured in conditioned medium were investigated with quantitative real time polymerase chain reaction(qRT-PCR).The MMP-2 and MMP-9 mRNA expression and activity were detected with qRT-PCR and gelatin zymography assays,respectively.The effect of activated STAT3 on 27 HC-induced EndMT was validated by Western blot,immunofluorescence staining,and cell transfection assays.The migration ability of BC cells was evaluated with Transwell assays.Results:We found that 27 HC induced EndMT in HMEC-1 and HUVECs,and 27 HC-induced EndMT facilitated EMT and BC cell migration.The 27 HC-induced EMT of BC cells also promoted EndMT and HUVEC migration.Investigation of the underlying molecular mechanisms revealed that STAT3 knockdown repressed EndMT in HUVECs as well as migration in BC cells induced with 27 HC.In addition,C646 and resveratrol,inhibitors of STAT3 acetylation,repressed the expression of Ac-STAT3,p-STAT3,and EndMT markers in HUVECs exposed to 27 HC;these HUVECs in turn attenuated the migration ability of BC cells in 27 HC-induced EndMT.Conclusions:Cross-talk between 27 HC-induced EndMT and EMT was observed in the TME.Moreover,activation of STAT3 signaling was found to be involved in 27 HC-induced EndMT.

Combination of Evodiamine with Berberine Reveals a Regulatory Effect on the Phenotypic Transition of Colon Epithelial Cells Induced by CCD-18Co

Objective Transdifferentiation exists between stromal cells or between stromal cells and cancer cells.Evodiamine and berberine are predominant pharmacological components of Zuojin pill,a prescription of Traditional Chinese Medicine,playing crucial functions in remolding of tumor microenvironment.This study aimed to explore the effect of combination of evodiamine with berberine(cBerEvo)on the phenotypic transition of colon epithelial cells induced by tumor-associated fibroblasts,as well as the involved mechanisms.Methods Human normal colon epithelial cell line HCoEpiC cells were treated with the prepared conditioned medium of CCD-18 Co,a human colon myofibroblast line,to induce epithelial-mesenchymal transition.Phase contrast microscope was used to observe the morphological changes.Epithelial-mesenchymal transition markers including E-cadherin,vimentin and alpha-smooth muscle actin(α-SMA)were observed with immunofluorescence microscopy.Migration was assessed by wound healing assay.Western blotting was used to detect the expressions of E-cadherin,vimentin,α-SMA,Snail,ZEB1 and Smads.Results In contrast to the control,the tumor-associated fibroblasts-like CCD-18 Co cells induced downregulation of E-cadherin and up-regulation of vimentin,α-SMA,Snail and ZEB1(P<0.05),and promoted migration of HCoEpiCs(P<0.05),with over expression of Smads including Smad2,p-Smad2,Smad3,p-Smad3 and Smad4(P<0.05),which were abolished by a transforming growth factor-β(TGF-β)receptor inhibitor LY364947 and by cBerEvo in a concentration dependent manner.In addition,cBerEvo-inhibited ratios of p-Smad2/Smad2 and p-Smad3/Smad3 were also dose dependent.Conclusion The above results suggest that cBerEvo can regulate the differentiation of colon epithelial cells induced by CCD-18 Co through suppressing activity of TGF-β/Smads signaling pathway.

The prognostic and therapeutic implications of circulating tumor cell phenotype detection based on epithelial-mesenchymal transition markers in the first-line chemotherapy of HER2-negative metastatic breast cancer

Background:Epithelial-mesenchymal transition(EMT)is implicated in the metastatic process and presents a chal-lenge to epithelial cell adhesion molecule-based detection of circulating tumor cells(CTCs),which have been demon-strated to be a prognostic indicator in metastatic breast cancer.Although evidence has indicated that heterogeneity of CTCs based on EMT markers is associated with disease progression,no standard recommendations have been established for clinical practice.This study aimed to evaluate the prognostic significance of dynamic CTC detection based on EMT for metastatic breast cancer patients.Methods:We enrolled 108 human epidermal growth factor receptor 2-negative metastatic breast cancer patients from the prospective phase III CAMELLIA study and applied the CanPatrol CTC enrichment technique to identify CTC phenotypes(including epithelial CTCs,biphenotypic epithelial/mesenchymal CTCs,and mesenchymal CTCs)in peripheral blood samples.Receiver operating characteristic curve analyses of total CTC count and the proportion of mesenchymal CTCs for predicting the 1-year progression-free survival(PFS)rate were conducted to determine the optimal cut-off values,and Kaplan-Meier analysis and Cox proportional hazards regression analysis were performed to investigate the prognostic value of the cut-off values of both total CTC count and the proportion of mesenchymal CTCs in combination.Results:For predicting the 1-year PFS rate,the optimal cut-off value of total CTC count was 9.5(Area under the curve[AUC]=0.538,95%confidence interval[CI]=0.418-0.657),and that of the proportion of mesenchymal CTCs was 10.7%(AUC=0.581,95%CI=0.463-0.699).We used the two cut-off values in combination to forecast PFS in which the total CTC count was equaled to or exceeded 10/5 mL with the proportion of mesenchymal CTCs surpassed 10.7%.Patients who met the combined criteria had significantly shorter median PFS than did those who did not meet the criteria(6.2 vs.9.9 months,P=0.010).A nomogram was constructed based on the criteria and significant clinicopatho-logical characteristics with a C-index of 0.613(P=0.010).Conclusions: The criteria, which combine the total CTC count and the proportion of mesenchymal CTCs, may be used to monitor therapeutic resistance and predict prognosis in patients with metastatic breast cancer.

The genomics of desmoplastic small round cell tumor reveals the deregulation of genes related to DNA damage response, epithelial-mesenchymal transition, and immune response

Background:Desmoplastic small round cell tumor(DSRCT)is a rare,aggressive,and poorly investigated simple sarcoma with a low frequency of genetic deregulation other than an Ewing sarcoma RNA binding protein 1(EWSR1)-Wilm’s tumor suppressor(WT1)translocation.We used whole-exome sequencing to interrogate six consecutive pretreated DSRCTs whose gene expression was previously investigated.Methods:DNA libraries were prepared from formalin-fixed,paraffin-embedded archival tissue specimens following the Agilent SureSelectXT2 target enrichment protocol and sequenced on Illumina NextSeq 500.Raw sequence data were aligned to the reference genome with Burrows-Wheeler Aligner algorithm.Somatic mutations and copy number alterations(CNAs)were identified using MuTect2 and EXCAVATOR2,respectively.Biological functions associated with altered genes were investigated through Ingenuity Pathway Analysis(IPA)software.Results:A total of 137 unique somatic mutations were identified:133 mutated genes were case-specific,and 2 were mutated in two cases but in different positions.Among the 135 mutated genes,27%were related to two biological categories:DNA damage-response(DDR)network that was also identified through IPA and mesenchymal-epithelial reverse transition(MErT)/epithelial-mesenchymal transition(EMT)already demonstrated to be relevant in DSRCT.The mutated genes in the DDR network were involved in various steps of transcription and particularly affected pre-mRNA.Half of these genes encoded RNA-binding proteins or DNA/RNA-binding proteins,which were recently rec-ognized as a new class of DDR players.CNAs in genes/gene families,involved in MErT/EMT and DDR,were recurrent across patients and mostly segregated in the MErT/EMT category.In addition,recurrent gains of regions in chromosome 1 involving many MErT/EMT gene families and loss of one arm or the entire chromosome 6 affecting relevant immune-regulatory genes were recorded.Conclusions:The emerging picture is an extreme inter-tumor heterogeneity,characterized by the concurrent deregulation of the DDR and MErT/EMT dynamic and plastic programs that could favour genomic instability and explain the refractory DSRCT profile.

Cancer stem cell plasticity and tumor hierarchy

The origins of the complex process of intratumoral heterogeneity have been highly debated and different cellular mechanisms have been hypothesized to account for the diversity within a tumor. The clonal evolution and cancer stem cell(CSC) models have been proposed as drivers of this heterogeneity. However, the concept of cancer stem cell plasticity and bidirectional conversion between stem and non-stem cells has added additional complexity to these highly studied paradigms and may help explain the tumor heterogeneity observed in solid tumors. The process of cancer stem cell plasticity in which cancer cel s harbor the dynamic ability of shifting from a non-CSC state to a CSC state and vice versa may be modulated by specific microenvironmental signals and cellular interactions arising in the tumor niche. In addition to promoting CSC plasticity, these interactions may contribute to the cellular transformation of tumor cells and affect response to chemotherapeutic and radiation treatments by providing CSCs protection from these agents. Herein, we review the literature in support of this dynamic CSC state, discuss the effectors of plasticity, and examine their role in the development and treatment of cancer.

Cancer-associated fibroblasts in digestive tumors

The significant influence of tumor stroma on malignant cells has been extensively investigated in this era of targeted therapy. The tumor microenvironment, as a dynamic system, is orchestrated by various cells including tumor vascular composing cells, inflammatory cells and fibroblasts. As a major and important component in tumor stroma, increasing evidence has shown that spindle-shaped cancer-associated fibroblasts (CAFs) are a significant modifier of cancer evolution, and promote tumorigenesis, tumor invasion and metastasis by stimulating angiogenesis, malignant cell survival, epithelial-mesenchymal transition (EMT) and proliferation via direct cell-to-cell contact or secretion of soluble factors in most digestive solid tumors. CAFs are thought to be activated, characterized by the expression of &#x003b1;-smooth muscle actin, fibroblast activated protein, fibroblast specific protein, vimentin, fibronectin, etc. They are hypothesized to originate from normal or aged fibroblasts, bone marrow-derived mesenchymal cells, or vascular endothelial cells. EMT may also be an important process generating CAFs, and most probably, CAFs may originate from multiple cells. A close link exists between EMT, tumor stem cells, and chemo-resistance of tumor cells, which is largely orchestrated by CAFs. CAFs significantly induce immunosuppression, and may be a prognostic marker in various malignancies. Targeted therapy toward CAFs has displayed promising anticancer efficacy, which further reinforces the necessity to explore the relationship between CAFs and their hosts.

Circulating tumor cells(CTCs)in breast cancer:a diagnostic tool for prognosis and molecular analysis

Metastatic breast cancer （MBC） is characterized by a combination of tumor growth, proliferation and metastatic progression and is typically managed with palliative intent. The benefit of standard systemic therapies is relatively limited and the disease is considered incurable suggesting the need to investigate the biological drivers of the various phases of the metastatic process in order to improve the selection of molecularly driven therapies. The detection, enumeration and molecular analysis of circulating tumor cells （CTCs） provide an intriguing opportunity to advance this knowledge. CTCs enumerated by the Food and Drugs Administration-cleared CellSearchTM system are an independent prognostic factor of progression- free survival （PFS） and overall survival （OS） in MBC patients. Several published papers demonstrated the poor prognosis for MBC patients that presented basal CTC count _〉5 in 7.5 mL of blood. Therefore, the enumeration of CTCs during treatment for MBC provides a tool with the ability to predict progression of disease earlier than standard timing of anatomical assessment using conventional radiological tests. During the metastatic process cancer cells exhibit morphological and phenotypic plasticity undergoing epithelial- mesenchymal transition （EMT）. This important phenomenon is associated with down regulation of epithelial marker （e.g., EpCAM） with potential limitations in the applicability of current CTCs enrichment methods. Such observations translated in a number of investigations aimed at improving our capabilities to enumerate and perform molecular characterization of CTCs. Theoretically, the phenotypic analysis of CTCs can represent a ＂liquid＂ biopsy of breast tumor that is able to identify a new potential target against the metastatic disease and advance the development and monitoring of personalized therapies.

Circulating tumor cells isolation:the "post-EpCAM era"

Circulating tumor cells （CTCs） represent a submicroscopic fraction detached from a primary tumor and in transit to a secondary site. The prognostic significance of CTCs in metastatic cancer patients was demonstrated for the first time more than ten years ago. To date, it seems clear enough that CTCs are highly heterogeneous and dynamically change their shape. Thus, the inadequacy of epithelial cell adhesion molecule （EpCAM） as universal marker for CTCs detection seems unquestionable and alternative methods able to recognize a broader spectrum of phenotypes are definitely needed. In this review the pleiotropic functions of EpCAM are discussed in detail and the role of the molecule in the biology of CTCs is critically dissected.

lncRNA AC005224.4/miR-140-3p/SNAI2 regulating axis facilitates the invasion and metastasis of ovarian cancer through epithelial-mesenchymal transition

Background:Ovarian cancer is one of the most widespread malignant diseases of the female reproductive system worldwide.The plurality of ovarian cancer is diagnosed with metastasis in the abdominal cavity.Epithelial-mesenchymal transition(EMT)exerts a vital role in tumor cell metastasis.However,it remains unclear whether long non-coding RNA(lncRNA)are implicated in EMT and influence ovarian cancer cell invasion and metastasis.This study was designed to investigate the impacts of lncRNA AC005224.4 on ovarian cancer.Methods:LncRNA AC005224.4,miR-140-3p,and snail family transcriptional repressor 2(SNAI2)expression levels in ovarian cancer and normal ovarian tissues were determined using real-time quantitative polymerase chain reaction(qRT-PCR).Cell Counting Kit-8(CCK-8)and Transwell(migration and invasion)assays were conducted to measure SKOV3 and CAOV-3 cell proliferation and metastasis.E-cadherin,N-cadherin,Snail,and Vimentin contents were detected using Western blot.Nude mouse xenograft assay was utilized to validate AC005224.4 effects in vivo.Dual-luciferase reporter gene assay confirmed the targeted relationship between miR-140-3p and AC005224.4 or SNAI2.Results:AC005224.4 and SNAI2 upregulation and miR-140-3p downregulation were observed in ovarian cancer tissues and cells.Silencing of AC005224.4 observably moderated SKOV3 and CAOV-3 cell proliferation,migration,invasion,and EMT process in vitro and impaired the tumorigenesis in vivo.miR-140-3p was a target of AC005224.4 and its reduced expression level was mediated by AC005224.4.miR-140-3p mimics decreased the proliferation,migration,and invasion of ovarian cancer cells.SNAI2 was identified as a novel target of miR-140-3p and its expression level was promoted by either AC005224.4 overexpression or miR-140-3p knockdown.Overexpression of SNAI2 also facilitated ovarian cancer cell viability and metastasis.Conclusion:AC005224.4 was confirmed as an oncogene via sponging miR-140-3p and promoted SNAI2 expression,contributing to better understanding of ovarian cancer pathogenesis and shedding light on exploiting the novel lncRNA-directed therapy against ovarian cancer.

hnRNP E1 at the crossroads of translational regulation of epithelial-mesenchymal transition

The epithelial-mesenchymal transition(EMT),in which cells undergo a switch from a polarized,epithelial phenotype to a highly motile fibroblastic or mesenchymal phenotype is fundamental during embryonic development and can be reactivated in a variety of diseases including cancer.Spatio-temporally-regulated mechanisms are constantly orchestrated to allow cells to adapt to their constantly changing environments when disseminating to distant organs.Although numerous transcriptional regulatory factors are currently well-characterized,the post-transcriptional control of EMT requires continued investigation.The hnRNP E1 protein displays a major role in the control of tumor cell plasticity by regulating the translatome through multiple non-redundant mechanisms,and this role is exemplified when E1 is absent.hnRNP E1 binding to RNA molecules leads to direct or indirect translational regulation of specific sets of proteins:(1)hnRNP E1 binding to specific targets has a direct role in translation by preventing elongation of translation;(2)hnRNP E1-dependent alternative splicing can prevent the generation of a competing long non-coding RNA that acts as a decoy for microRNAs(miRNAs)involved in translational inhibition of EMT master regulators;(3)hnRNP E1 binding to the 3'untranslated region of transcripts can also positively regulate the stability of certain mRNAs to improve their translation.Globally,hnRNP E1 appears to control proteome reprogramming during cell plasticity,either by direct or indirect regulation of protein translation.

Tumor budding as a potential prognostic marker in determining the behavior of primary liver cancers

Hepatocellular(HCC)and intrahepatic cholangiocarcinoma(ICC),the most common primary tumors of the liver,are among the most important causes of cancer deaths worldwide.Because patients with primary liver tumors are frequently diagnosed at an advanced stage and have high mortality,many efforts have been made to identify new markers to determine their behavior and treatment,similar to those in other solid organ tumors.Recently,morphological assessment of tumor budding(TB)has been revealed as a promising prognostic finding to predict tumor behavior and survival across several different tumor types.Currently,the TB score in colorectal cancer has been revealed as an important parameter in pathology report protocols to determine the course of the disease.Regarding the liver,despite enormous data showing that many mechanisms involved in TB are associated with tumor behavior in both HCC and ICC,studies focusing on the role of TB in predicting the behavior and prognosis of these tumors have started to be investigated very recently.The purpose of this review is to present data about TB in primary tumors of the liver,pointing out the potential role of this parameter in determining the course of the disease,and emphasize the need to increase the number of further studies focusing on the evaluation of this parameter with an overview of the mechanisms involved in TB.

低氧微环境通过TGFBI调控Wnt/β-catenin通路介导胰腺癌化疗耐药及机制研究

目的:研究低氧微环境通过TGFBI调控胰腺癌耐药的作用及分子机制。方法:以CCK-8方法检测细胞增殖;以Western blotting技术检测蛋白表达水平;以ImageJ软件分析蛋白灰度值;RNAi技术用于敲减TGFBI基因。结果:TGFBI在Panc-1细胞中表达比正常细胞增强;低氧促进胰腺癌细胞Panc-1增殖并减弱顺铂对Panc-1的抑制作用,而高氧抑制Panc-1细胞增殖并加强顺铂的杀伤作用;低氧促进TGFBI表达及EMT行为;低氧通过TGFBI调控Panc-1细胞增殖及顺铂的杀伤作用;低氧通过TGFBI调控Wnt/β-catenin信号,进而促进EMT行为。结论:低氧微环境通过增强TGFBI表达促进胰腺癌细胞增殖及耐药;低氧微环境通过TGFBI激活Wnt/β-catenin信号通路,促进EMT标志分子表达。

外泌体参与结直肠癌肝转移发病机制的研究进展

结直肠癌是全世界最常见的第三大癌症,60%的患者在未经过有效治疗的情况下会发生肝转移。其发病率和死亡率均很高。尽管诊断和治疗技术取得了很大进展,但结直肠癌肝转移(colorectal cancer liver metastasis,CRLM)患者的生存率仍然很低。外泌体作为细胞间通讯中的重要介质被广泛研究,在CRLM发病过程中的每一步都有非常重要的影响。本文归纳了不同来源、不同内含物外泌体通过包括:促进上皮-间充质转化(epithelial-mesenchymal transition,EMT)、调节细胞外基质(extracellular matrix,ECM)、增加血管生成和血管通透性、促进转移前生态位(pre-metastatic niche,PMN)形成、参与免疫抑制等途径来影响CRLM发病的机制,以期为未来CRLM提供潜在诊断及治疗靶点。

层黏连蛋白基质在肿瘤细胞行为及血管生成拟态形成中的机制研究

血管生成拟态(vasculogenic mimicry,VM)描述了肿瘤细胞在无内皮细胞参与下形成新的微循环模式的过程。临床上,VM与侵袭性表型和较差的患者生存率有关。以前的许多研究都集中在血管生成因子方面;最近的研究发现,肿瘤细胞周围的细胞外基质对肿瘤发展具有显著调控作用。细胞外基质蛋白质可能授予肿瘤细胞形成血管生成拟态的能力。在本研究中,我们研究了层黏连蛋白(laminin,LN)基质在黑色素瘤和骨肉瘤的肿瘤进程和VM形成中的作用。相较于Control组,高浓度LN基质培养下,肿瘤细胞的黏附、增殖、迁移、干性表达和VM形成能力显著增强;利用免疫荧光染色和实时定量PCR分析其内在的分子机制,结果显示:与对照组相比,层黏连蛋白基质可以显著促进肿瘤细胞CD133的表达,同时E-钙黏着蛋白I的mRNA表达下调(P<0.05),而Integrin、N-cadherin、Vimentin以及Snail、Twist的mRNA表达上调(P<0.05)。以上研究结果表明,层黏连蛋白促进肿瘤细胞的黏附、增殖、迁移和VM形成能力,并揭示了VM形成的潜在机制,为后期抗血管生成拟态的诊疗提供了新的思路。

Cytokine- and chemokine-induced inflammatory colorectal tumor microenvironment: Emerging avenue for targeted therapy

Colorectal cancer(CRC)is a predominant life-threatening cancer,with liver and peritoneal metastases as the primary causes of death.Intestinal inflammation,a known CRC risk factor,nurtures a local inflammatory environment enriched with tumor cells,endothelial cells,immune cells,cancer-associated fibroblasts,immunosuppressive cells,and secretory growth factors.The complex interactions of aberrantly expressed cytokines,chemokines,growth factors,and matrix-remodeling enzymes promote CRC pathogenesis and evoke systemic responses that affect disease outcomes.Mounting evidence suggests that these cytokines and chemokines play a role in the progression of CRC through immunosuppression and modulation of the tumor microenvironment,which is partly achieved by the recruitment of immunosuppressive cells.These cells impart features such as cancer stem cell-like properties,drug resistance,invasion,and formation of the premetastatic niche in distant organs,promoting metastasis and aggressive CRC growth.A deeper understanding of the cytokineand chemokine-mediated signaling networks that link tumor progression and metastasis will provide insights into the mechanistic details of disease aggressiveness and facilitate the development of novel therapeutics for CRC.Here,we summarized the current knowledge of cytokine-and chemokine-mediated crosstalk in the inflammatory tumor microenvironment,which drives immunosuppression,resistance to therapeutics,and metastasis during CRC progression.We also outlined the potential of this crosstalk as a novel therapeutic target for CRC.The major cytokine/chemokine pathways involved in cancer immunotherapy are also discussed in this review.

Analysis of the role of dihydromyricetin derived from vine tea(Ampelopsis grossedentata)on multiple myeloma by activating STAT1/RIG-I axis

Multiple myeloma(MM)is a plasma cell malignancy and remains incurable as it lacks effective curative approaches;thus,novel therapeutic strategies are desperately needed.The study aimed to explore the therapeutic role of dihydromyricetin(DHM)in MM and explore its mechanisms.Human MM and normal plasma samples,human MM cell lines,and normal plasma cells were used for in vitro experiments.Cell counting kit-8(CCK-8),flow cytometry,and trans-well assays were performed for the assessment of cell viability,apoptosis,migration,and invasion,respectively.Quantitative real-time polymerase chain reaction(qRT-PCR)was employed to assess the mRNA expression of signal transducer and activator of transcription 1(STAT1)and retinoic acid-inducible gene I(RIG-I).Western blotting was employed to assess E-cadherin,N-cadherin,signal transducer,STAT1,p-STAT1,and RIG-I protein expression.A tumor xenograft model was used for in vivo experiments.Here,dihydromyricetin(DHM)dose-dependently restrained viability,apoptosis,migration,and invasion,and facilitated apoptosis of U266 cells.After DHM treatment,the Ecadherin level was increased and the N-cadherin level was decreased in U266 and RPMI-8226 cells,suggesting the inhibitory effects of DHM on epithelial-mesenchymal transition(EMT)in MM.Besides,the levels of p-STAT1/STAT1 and RIG-I were down-regulated in MM.However,the STAT1 inhibitor fludarabine undid the suppressive effect of DMH on the malignant characteristics of U266 cells.Also,DHM inhibited MM tumor growth and EMT,and activated STAT1/RIG-I pathway in vivo.Collectively,this study first revealed that DHM can restrain EMT and tumor growth in MM by activating STAT1/RIG-I signaling,which provides a novel drug for the treatment of MM.