This article reviews the molecular structure, expression pattern, physiological function, pathological roles and molecular mechanisms of Twist1 in development, genetic disease and cancer. Twist1 is a basic helix-loop-helix domain-containing transcription factor. It forms homo- or hetero-dimers in order to bind the Nde1 E-box element and activate or repress its target genes. During development, Twist1 is essential for mesoderm specification and differentiation. Heterozygous loss-of-function mutations of the human Twist1 gene cause several diseases including the Saethre-Chotzen syndrome. The Twist1-null mouse embryos die with unclosed cranial neural tubes and defective head mesenchyme, somites and limb buds. Twist1 is expressed in breast, liver, prostate, gastric and other types of cancers, and its expression is usually associated with invasive and metastatic cancer phenotypes. In cancer cells, Twist1 is upregulated by multiple factors including SRC-1, STAT3, MSX2, HIF-1α, integrin-linked kinase and NF-κB. Twist1 significantly enhances epithelial-mesenchymal transition (EMT) and cancer cell migration and invasion, hence promoting cancer metastasis. Twist1 promotes EMT in part by directly repressing E-cadherin expression by recruiting the nucleosome remodeling and deacetylase complex for gene repression and by upregulating Bmi1, AKT2, YB-1, etc. Emerging evidence also suggests that Twist1 plays a role in expansion and chemotherapeutic resistance of cancer stem cells. Further understanding of the mechanisms by which Twist1 promotes metastasis and identification of Twist1 functional modulators may hold promise for developing new strategies to inhibit EMT and cancer metastasis.

/pdf/normal-and-disease-related-biological-functions-of-twist1-dxhtzjyv94.pdf

Normal and disease-related biological functions of Twist1 and underlying molecular mechanisms.

In 1999, The American Journal of Pathology published an article entitled “Vascular Channel Formation by Human Melanoma Cells in Vivo and in Vitro: Vasculogenic Mimicry,” by Maniotis and colleagues, which ignited a spirited debate for several years and earned distinction as a citation classic Tumor cell vasculogenic mimicry (VM) refers to the plasticity of aggressive cancer cells forming de novo vascular networks, which thereby contribute to perfusion of rapidly growing tumors, transporting fluid from leaky vessels, and/or connecting with the constitutional endothelial-lined vasculature The tumor cells capable of VM share a plastic, transendothelial phenotype, which may be induced by hypoxia Since VM was introduced as a novel paradigm for melanoma tumor perfusion, many studies have contributed new findings illuminating the underlying molecular pathways supporting VM in a variety of tumors, including carcinomas, sarcomas, glioblastomas, astrocytomas, and melanomas Facilitating the functional plasticity of tumor cell VM are key proteins associated with vascular, stem cell, and hypoxia-related signaling pathways, each deserving serious consideration as potential therapeutic targets and diagnostic indicators of the aggressive, metastatic phenotype

Tumor Cell Vasculogenic Mimicry: From Controversy to Therapeutic Promise

Vasculogenic mimicry (VM) refers to the unique capability of aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks. In the study we demonstrated that CD133 expression was the highest in triple-negative (TN) breast cancer specimens. Importantly, VM showed statistical correlation with CD133(+) expression. The presence of the close relationship between VM and CD133(+) expression might be central for TN tumor relapse and progression. The TN breast cancer cell line, MDA-MB-231 cells developed a range of colony morphologies paralleling the holoclone, meroclone and paraclone morphologies produced by normal keratinocytes and other epithelial cancer cell lines when plated at clonal densities. Holoclone cells were capable of forming more colonies on soft agar than meroclone cells and paraclone cells, suggesting that holoclone cells had higher self-renew potential and might harbors cancer stem cells (CSCs) subpopulation. Strikingly, it was holoclone that displayed CD133(+) phenotype and formed VM. In addition, holoclone acquired endothelial cell marker vascular endothelial-cadherin expression and upregulated VM mediators matrix metalloproteinase (MMP)-2 and MMP-9 expression. The subpopulation with holoclone morphology, CD133(+) phenotype and CSCs characteristics might have the capacity of transdifferentiation and contributed to VM in TN breast cancer. The related molecular pathways may be used as novel therapeutic targets for the inhibition of angiogenesis and metastasis in TN breast carcinoma.

CD133 + cells with cancer stem cell characteristics associates with vasculogenic mimicry in triple-negative breast cancer

The epithelial to mesenchymal transition (EMT) plays crucial roles in the formation of the body plan and also in the tumor invasion process. In addition, EMT also causes disruption of cell-cell adherence, loss of apico-basal polarity, matrix remodeling, increased motility and invasiveness in promoting tumor metastasis. The tumor microenvironment plays an important role in facilitating cancer metastasis and may induce the occurrence of EMT in tumor cells. A large number of inflammatory cells infiltrating the tumor site, as well as hypoxia existing in a large area of tumor, in addition many stem cells present in tumor microenvironment, such as cancer stem cells (CSCs), mesenchymal stem cells (MSCs), all of these may be the inducers of EMT in tumor cells. The signaling pathways involved in EMT are various, including TGF-β, NF-κB, Wnt, Notch, and others. In this review, we discuss the current knowledge about the role of the tumor microenvironment in EMT and the related signaling pathways as well as the interaction between them.

/pdf/epithelial-mesenchymal-transition-in-tumor-microenvironment-32i7bvy4gy.pdf

Epithelial-Mesenchymal Transition in tumor microenvironment

Tumor cell vasculogenic mimicry (VM) describes the functional plasticity of aggressive cancer cells forming de novo vascular networks, thereby providing a perfusion pathway for rapidly growing tumors, transporting fluid from leaky vessels, and/or connecting with endothelial-lined vasculature. The underlying induction of VM seems to be related to hypoxia, which may also promote the plastic, transendothelial phenotype of tumor cells capable of VM. Since its introduction in 1999 as a novel paradigm for melanoma tumor perfusion, many studies have contributed new insights into the underlying molecular pathways supporting VM in a variety of tumors, including melanoma, glioblastoma, carcinomas, and sarcomas. In particular, critical VM-modulating genes are associated with vascular (VE-cadherin, EphA2, VEGF receptor 1), embryonic and/or stem cell (Nodal, Notch4), and hypoxia-related (hypoxia-inducible factor, Twist1) signaling pathways. Each of these pathways warrants serious scrutiny as potential therapeutic, vascular targets, and diagnostic indicators of plasticity, drug resistance, and the aggressive metastatic phenotype.

https://clincancerres.aacrjournals.org/content/clincanres/early/2012/03/31/1078-0432.CCR-11-3237.full.pdf

Molecular Pathways: Vasculogenic Mimicry in Tumor Cells: Diagnostic and Therapeutic Implications

https://aasldpubs.onlinelibrary.wiley.com/doi/pdf/10.1002/hep.23311

Expression and functional significance of Twist1 in hepatocellular carcinoma: its role in vasculogenic mimicry.

AIM: To study the effect of sulindac on colon cancer induction in mice.

METHODS: The chemo-preventive action of 80 ppm sulindac fed during initiation and post-initiation and 100 ppm sulindac fed during progressive stages of induction of colon carcinogenesis in mice was investigated using 1,2-dimethylhydrazine (DMH). Using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) technique and PCNA immunohistochemical staining, we observed the apoptotic and proliferative cell density changes at different carcinogenic stages and the effect of sulindac on these two phenomena.

RESULTS: Dietary sulindac significantly inhibited the incidence of colonic neoplasmas in mice. Compared with the control group, feeding sulindac during initiation and post-initiation stages inhibited the incidence by 46.7-50.4%, and feeding sulindac during progressive stages inhibited the incidence by 41.1%. Animals that were fed sulindac showed less serious pathological changes than those that were fed the control diet (P<0.01, H = 33.35). There was no difference in the density of proliferating cells among those groups which were or were not fed sulindac. In the same period, feeding sulindac resulted in a higher density of apoptotic cells than feeding control diet.

CONCLUSION: Sulindac has an anti-carcinogenic function in mice. Its effect on preventing colon carcinogenesis is better than its effect on treating established tumors. By inducing apoptosis, sulindac inhibited the development of colon cancer and delayed canceration. Sulindac has no effect on proliferation. The anti-carcinogenic properties of sulindac are most effective in the moderate and severe stages of dysplasia and canceration.

Sulindac induces apoptosis and protects against colon carcinoma in mice.

OBJECTIVE: To explore if vasculogenic mimicry (VM) exists in hepatocellular carcinoma (HCC) and to explain the clinical significance of VM. METHODS: Ninety-nine HCC resection specimens with complete clinical and prognostic data were collected. Immunohistochemical staining of CD31 and CD105, hepatocyte and PAS staining of the histological preparations were conducted to explore if VM exists in those HCC. RESULTS: 12.12% (12 specimens) of the 99 specimens exhibited evidence of VM. One of 40 HCC specimens (2.5%) which belong to Edmondson pathologic grade I-II exhibited VM; 11 of 59 HCC specimens which belong to Edmondson pathologic grade III-VI (18.64%) exhibited VM, the low differentiated HCC (grade III-VI) exhibited more VM specimens than the high differentiated HCC (grade I-II) (chi2=4.416, P < 0.05). The biological behavior of VM was assessed and the stages of the cancers, using the TNM (tumor, node, metastases) classification criteria, were analyzed. These parameters of the VM and non-VM groups were compared. The mean TNM stage of the VM group was not more advanced than that of the non-VM group. The hematogenous metastases ( lung, bone, peritoneum et al) between the 2 groups were compared, and in the VM group the hematogenous metastasis rate was higher (chi2=8.873, P < 0.01). Kaplan-Meier actuarial survival curves were used to compare the VM group (n = 12) with the non-VM group (n = 87). Median survival time of the VM group was 9 months and that of the non-VM group was 31 months. The VM group had a lower survival rate than the non-VM group (P < 0.01). CONCLUSION: VM exists in HCC, and the higher invasive HCCs exhibit more VM than the less invasive HCCs. The HCC patients in the VM group had a higher rate of hematogenous metastases, a lower survival rate, and a poorer prognosis.

A study on vasculogenic mimicry in hepatocellular carcinoma

Objective To explore the expression and significance of E-cadherin （E-cad） and β-catenin （β-cat） in synovial sarcoma. Methods Expression of E-cad and β-cat in 72 cases of synovial sarcoma were detected by tissue microarray technique and immunohistochemistry. The relationships between E-cad and β-cat expression and clinicopathological data and survival rate were analyzed. Results （ 1 ） 95.1% of dots on the tissue microarrays were observable morphologically. The background was clear and the contrast was vivid after immunohistochemistry. （2） The expression of E-cad was reduced in 56 patients （77.8%） and that of β-cat was reduced in 51 patients （70.8%）. （3）In patients with synovial sarcoma of monophasic fibrous type, grade Ⅲ, and in patients with recurrence or metastasis, CK-negative and EMA- negative the rates of reduced expression of E-cad and β-cat were significantly higher than those with primary sarcoma of biphasic type, grade Ⅱ , CK-positive and EMA positive （P 〈0.05 for all）. （4） The survival of synovial sarcoma patients with E-cad and β-cat expressions preserved was significantly better than those with reduced expressions （P = 0. 012, P = 0. 047）. Conclusion The expression of E-cad and β-cat is correlated with cell differentiation. Reduced expression of E-cad and β-cat may indicate a high potential of recurrence or metastasis and poor prognosis. Tissue microarray technique is applicable for retrospective studies of large sample size.

Key words: 
Synovial sarcoma ;  E-cadherin;  β-catenin;  Tissue microarray

Yi xin Liu

Papers

Expression and functional significance of Twist1 in hepatocellular carcinoma: its role in vasculogenic mimicry.

Sulindac induces apoptosis and protects against colon carcinoma in mice.

A study on vasculogenic mimicry in hepatocellular carcinoma

[Expressions and significance of E-cadherin and beta-catenin in synovial sarcoma].