The association of transforming growth factor-beta 1 with myometrial invasion of endometrial carcinomas through effects on matrix metalloproteinase

Clinical significance of MMP-9 overexpression in endometrial cancer: A PRISMA-compliant meta-analysis

OBJECTIVE

Several studies have found that MMP-9, one of the extracellular matrix-degrading proteinases, was involved in EC's (endometrial cancer) clinical progression and prognosis. However, the results involving the associations of MMP-9 expression with risk, clinical features and prognosis of EC were conflicting. Therefore, we performed a systematic review and meta-analysis to clarify the correlation of MMP-9 expression with EC.

METHODS

Relative studies involving the associations between MMP-9 expression and EC were retrieved from PubMed, Embase, Web of Science and CNKI (China National Knowledge Infrastructure) electronic databases. OR (odds ratio) with 95% CI (confidence interval) was applied to evaluate the associations of MMP-9 expression with risk and clinical features of EC. Furthermore, we evaluated the role of MMP-9 expression in prognosis of EC using HR and 95% CI. The funnel plots and Begg test were used to assess the publication bias.

RESULTS

A total of 28 eligible studies were acquired from Pubmed, Embase, Web of science and CNKI databases. We found MMP-9 overexpression was significantly associated with the risk of EC (OR = 11.02, 95% CI = 7.51-16.16, P < 0.05). In the meantime, MMP-9 overexpression was significantly associated with the tumor grade, FIGO stage, lymph node metastasis and myometrial invasion (Tumor grade: OR = 1.68, 95% CI = 1.09-2.58, P < 0.05; FIGO stage: OR = 3.25, 95% CI = 1.73-6.08, P < 0.05; Lymph node metastasis: OR = 2.98, 95% CI = 1.27-7.03, P < 0.05; Myometrial invasion: OR = 2.42, 95% CI = 1.42-4.12, P < 0.05) in Asians. In addition, the overall results showed that MMP-9 overexpression predicted a worse prognosis of EC (OR = 1.82, 95% CI = 1.01-2.62, P < 0.05).

CONCLUSIONS

MMP-9 overexpression might be a potential predictor of poor clinical progression and prognosis of EC.

Lack of extracellular matrix switches TGF-β induced apoptosis of endometrial cells to epithelial to mesenchymal transition

The extracellular matrix and the correct establishment of epithelial cell polarity plays a critical role in epithelial cell homeostasis and cell polarity. In addition, loss of tissue structure is a hallmark of carcinogenesis. In this study, we have addressed the role of extracellular matrix in the cellular responses to TGF-β. It is well known that TGF-β is a double-edged sword: it acts as a tumor suppressor in normal epithelial cells, but conversely has tumor-promoting effects in tumoral cells. However, the factors that determine cellular outcome in response to TGF-β remain controversial. Here, we have demonstrated that the lack of extracellular matrix and consequent loss of cell polarity inhibits TGF-β-induced apoptosis, observed when endometrial epithelial cells are polarized in presence of extracellular matrix. Rather, in absence of extracellular matrix, TGF-β-treated endometrial epithelial cells display features of epithelial-to-mesenchymal transition. We have also investigated the molecular mechanism of such a switch in cellular response. On the one hand, we found that the lack of Matrigel results in increased AKT signaling which is sufficient to inhibit TGF-β-induced apoptosis. On the other hand, we demonstrate that TGF-β-induced epithelial-to-mesenchymal transition requires ERK and SMAD2/3 activation. In summary, we demonstrate that loss of cell polarity changes the pro-apoptotic function of TGF-β to tumor-associated phenotype such as epithelial-to-mesenchymal transition. These results may be important for understanding the dual role of TGF-β in normal versus tumoral cells.

Loss of CD73 shifts transforming growth factor-β1 (TGF-β1) from tumor suppressor to promoter in endometrial cancer

In many tumors, CD73 (NT5E), a rate-limiting enzyme in adenosine biosynthesis, is upregulated by TGF-β and drives tumor progression. Conversely, CD73 is downregulated in endometrial carcinomas (EC) despite a TGF-β-rich environment. Through gene expression analyses of normal endometrium samples of the uterine cancer TCGA data set and genetic and pharmacological studies, we discovered CD73 loss shifts TGF-β1 from tumor suppressor to promoter in EC. TGF-β1 upregulated CD73 and epithelial integrity in vivo in the normal endometrium and in vitro in early stage EC cells. With loss of CD73, TGF-β1-mediated epithelial integrity was abrogated. EC cells developed TGF-β1-mediated stress fibers and macromolecule permeability, migration, and invasion increased. In human tumors, CD73 is downregulated in deeply invasive stage I EC. Consistent with shifting TGF-β1 activity, CD73 loss increased TGF-β1-mediated canonical signaling and upregulated cyclin D1 (CCND1) and downregulated p21 expression. This shift was clinically relevant, as CD73^Low/CCND1^High expression associated with poor tumor differentiation, increased myometrial and lymphatic/vascular space invasion, and patient death. Further loss of CD73 in CD73^Low expressing advanced stage EC cells increased TGF-β-mediated stress fibers, signaling, and invasiveness, whereby adenosine A1 receptor agonist, CPA, dampened TGF-β-mediated invasion. These data identify CD73 loss as essential for shifting TGF-β activity in EC.

Estrogen inhibits autophagy and promotes growth of endometrial cancer by promoting glutamine metabolism

Background

Excessive estrogen exposure is an important pathogenic factor in uterine endometrial cancer (UEC). Recent studies have reported the metabolic properties can influence the progression of UEC. However, the underlying mechanisms have not been fully elucidated.

Methods

Glutaminase (GLS), MYC and autophagy levels were detected. The biological functions of estrogen-MYC-GLS in UEC cells (UECC) were investigated both in vivo and in vitro.

Results

Our study showed that estrogen remarkably increased GLS level through up-regulating c-Myc, and enhanced glutamine (Gln) metabolism in estrogen-sensitive UEC cell (UECC), whereas fulvestrant (an ER inhibitor antagonist) could reverse these effects. Estrogen remarkably promoted cell viability and inhibited autophagy of estrogen sensitive UECC. However, CB-839, a potent selective oral bioavailable inhibitor of both splice variants of GLS, negatively regulated Gln metabolism, and inhibited the effects of Gln and estrogen on UECC’s growth and autophagy in vitro and / or in vivo.

Conclusions

CB-839 triggers autophagy and restricts growth of UEC by suppressing ER/Gln metabolism, which provides new insights into the potential value of CB-839 in clinical treatment of estrogen-related UEC.

Deregulation of Negative Controls on TGF-β1 Signaling in Tumor Progression

The multi-functional cytokine transforming growth factor-β1 (TGF-β1) has growth inhibitory and anti-inflammatory roles during homeostasis and the early stages of cancer. Aberrant TGF-β activation in the late-stages of tumorigenesis, however, promotes development of aggressive growth characteristics and metastatic spread. Given the critical importance of this growth factor in fibrotic and neoplastic disorders, the TGF-β1 network is subject to extensive, multi-level negative controls that impact receptor function, mothers against decapentaplegic homolog 2/3 (SMAD2/3) activation, intracellular signal bifurcation into canonical and non-canonical pathways and target gene promotor engagement. Such negative regulators include phosphatase and tensin homologue (PTEN), protein phosphatase magnesium 1A (PPM1A), Klotho, bone morphogenic protein 7 (BMP7), SMAD7, Sloan-Kettering Institute proto-oncogene/ Ski related novel gene (Ski/SnoN), and bone morphogenetic protein and activin membrane-bound Inhibitor (BAMBI). The progression of certain cancers is accompanied by loss of expression, overexpression, mislocalization, mutation or deletion of several endogenous repressors of the TGF-β1 cascade, further modulating signal duration/intensity and phenotypic reprogramming. This review addresses how their aberrant regulation contributes to cellular plasticity, tumor progression/metastasis and reversal of cell cycle arrest and discusses the unexplored therapeutic value of restoring the expression and/or function of these factors as a novel approach to cancer treatment.

TGF-β1 stimulates migration of type II endometrial cancer cells by down-regulating PTEN via activation of SMAD and ERK1/2 signaling pathways

PTEN acts as a tumor suppressor primarily by antagonizing the PI3K/AKT signaling pathway. PTEN is frequently mutated in human cancers; however, in type II endometrial cancers its mutation rate is very low. Overexpression of TGF-β1 and its receptors has been reported to correlate with metastasis of human cancers and reduced survival rates. Although TGF-β1 has been shown to regulate PTEN expression through various mechanisms, it is not yet known if the same is true in type II endometrial cancer. In the present study, we show that treatment with TGF-β1 stimulates the migration of two type II endometrial cancer cell lines, KLE and HEC-50. In addition, TGF-β1 treatment down-regulates both mRNA and protein levels of PTEN. Overexpression of PTEN or inhibition of PI3K abolishes TGF-β1-stimulated cell migration. TGF-β1 induces SMAD2/3 phosphorylation and knockdown of common SMAD4 inhibits the suppressive effects of TGF-β1 on PTEN mRNA and protein. Interestingly, TGF-β1 induces ERK1/2 phosphorylation and pre-treatment with a MEK inhibitor attenuates the suppression of PTEN protein, but not mRNA, by TGF-β1. This study provides important insights into the molecular mechanisms mediating TGF-β1-induced down-regulation of PTEN and demonstrates an important role of PTEN in the regulation of type II endometrial cancer cell migration.

TGFβ1 induces endometrial cancer cell adhesion and migration by up-regulating integrin αvβ3 via SMAD-independent MEK-ERK1/2 signaling

Endometrial cancer is the most common, and second most lethal, gynecological malignancy, and its rates of incidence and death are growing. This is likely attributable to increased numbers of high-risk type II endometrial cancers which account for ~30% of cases but ~75% of deaths due to their aggressive and metastatic behaviour. Histopathological and in vitro functional studies suggest that aberrant TGFβ1 signaling may contribute to endometrial cancer development and the acquisition of invasive/metastatic characteristics. However, little is known about the cellular and molecular mechanisms of TGFβ1 in high-risk endometrial cancers. In the present study, we examined the roles and mechanisms of TGFβ1 on cell adhesion and motility in type II endometrial cancer cell lines, KLE and HEC-1B. We show that treatment with TGFβ1 increases cell adhesion to vitronectin and transwell cell migration. We also demonstrate that TGFβ1 treatment increases integrin β3 and αv mRNA and protein levels via SMAD-independent MEK-ERK1/2 signaling. Importantly, siRNA depletion or antibody-mediated blocking of integrin αvβ3 reversed the effects of TGFβ1 on cell adhesion and migration. Our results suggest that TGFβ1-MEK-ERK1/2-integrin αvβ3 signaling could contribute to the invasive behaviour of high-risk endometrial cancer by promoting cell adhesion and migration.

Siegesbeckia orientalis Extract Inhibits TGFβ1-Induced Migration and Invasion of Endometrial Cancer Cells

Type II endometrial carcinoma typically exhibits aggressive metastasis and results in a poor prognosis. Siegesbeckia orientalis Linne is a traditional Chinese medicinal herb with several medicinal benefits, including the cytotoxicity against various cancers. This study investigates the inhibitory effects of S. orientalis ethanol extract (SOE) on the migration and invasion of endometrial cancer cells, which were stimulated by transforming growth factor β (TGFβ). The inhibitory effects were evaluated by determining wound healing and performing the Boyden chamber assay. This study reveals that SOE can inhibit TGFβ1-induced cell wound healing, cell migration, and cell invasion in a dose-dependent manner in RL95-2 and HEC-1A endometrial cancer cells. SOE also reversed the TGFβ1-induced epithelial-mesenchymal transition, including the loss of the cell-cell junction and the lamellipodia-like structures. Western blot analysis revealed that SOE inhibited the phosphorylation of ERK1/2, JNK1/2, and Akt, as well as the expression of MMP-9, MMP-2, and u-PA in RL95-2 cells dose-dependently. The results of this investigation suggest that SOE is a potential anti-metastatic agent against human endometrial tumors.

Clinicopathological Role of Serum-Derived Hyaluronan-Associated Protein (SHAP)-Hyaluronan Complex in Endometrial Cancer

The role of hyaluronan (HA), serum-derived HA-associated protein (SHAP)-HA complex and hyaluronan synthase (HAS) in endometrial carcinomas was investigated. The relationship of metalloproteinase (MMP) and its inhibitor (TIMP) with HA and the SHAP-HA complex was also examined. The expression of HAS1 was related to the depth of myometrial invasion and lymph-vascular space involvement. The serum levels of HA, SHAP-HA complex, MMP-9, and TIMP-1 were increased in related with the depth of myometrial invasion, histological grade and lymph-vascular space involvement. They were also higher in the HAS1-positive group compared to -negative group. The serum concentrations of HA and SHAP-HA complex had a significant correlation with the MMP-9 and TIMP-1. The patients with elevated SHAP-HA complex had the shorter disease-free survival. The multivariate analysis revealed that the SHAP-HA complex was the independent variable for disease-free survival of endometrial cancer patients. In conclusion, the elevation of serum SHAP-HA complex depended on the HAS1 expression and the SHAP-HA complex is a useful marker to predict disease recurrence in endometrial cancer patients. The SHAP-HA complex may promote the lymph-vascular space involvement and the synthesis and activation of MMP-9 and TIMP-1 in the progression of endometrial cancer.

S100A4 mediates endometrial cancer invasion and is a target of TGF-beta1 signaling

The molecular mechanisms of endometrial cancer invasion are poorly understood. S100A4, also known as FSP1 (fibroblast-specific protein 1), has long been known to be a molecular marker of fibrosis in a variety of different fibrotic diseases of the lungs, liver, kidney, and heart. We demonstrate here that increased expression of S100A4 is associated with advanced stage endometrial cancer and decreased recurrence free survival. To verify the essential role of S100A4 in invasiveness of endometrial cancer, S100A4 expression was downregulated by RNAi in HEC-1A cells, which resulted in undetectable S100A4 protein and significantly decreased migration and invasion. Owing to the established connection between TGF-beta1 and S100A4 induction in experimental models of kidney and liver fibrosis, we next examined whether TGF-beta1 could also regulate S100A4 in endometrial cancer cells. TGF-beta1 stimulated endometrial cancer cell migration and invasion with a concomitant increase in S100A4 protein. Induction of S100A4 was associated with the activation of Smads. TGF-beta1-mediated endometrial cancer cell motility was inhibited by S100A4 siRNA. In aggregate, these results suggest that S100A4 is a critical mediator of invasion in endometrial cancer and is upregulated by the TGF-beta1 signaling pathway. These results also suggest that endometrial cancer cell invasion and fibrosis share common molecular mechanisms.

Dichloroacetate induces apoptosis in endometrial cancer cells

PURPOSE

A recent landmark study demonstrated that Dichloroacetate (DCA) treatment promoted apoptosis in lung, breast, and glioblastoma cancer cell lines by shifting metabolism from aerobic glycolysis to glucose oxidation coupled with NFAT-Kv1.5 axis remodeling. The objective of this study was to determine whether DCA induces apoptosis in endometrial cancer cells and to assess apoptotic mechanism.

METHODS

A panel of endometrial cancer cell lines with varying degrees of differentiation was treated with DCA and analyzed for apoptosis via flow cytometry. Biological correlates such as gene expression, intracellular Ca(2+), and mitochondrial membrane potential were examined to assess apoptotic mechanism.

RESULTS

Initiation of apoptosis was observed in five low to moderately invasive cancer cell lines including Ishikawa, RL95-2, KLE, AN3CA, and SKUT1B while treatment had no effect on non-cancerous 293T cells. Two highly invasive endometrial adenocarcinoma cell lines, HEC1A and HEC1B, were found to be resistant to DCA-induced apoptosis. Apoptotic responding cell lines had a significant increase in early and late apoptotis, a decrease in mitochondrial membrane potential, and decreased Survivin transcript abundance, which are consistent with a mitochondrial-regulated mechanism. DCA treatment decreased intracellular calcium levels in most apoptotic responding cell lines which suggests a contribution from the NFAT-Kv1.5-mediated pathway. DCA treatment increased p53 upregulated modulator of apoptosis (PUMA) transcripts in cell lines with an apoptotic response, suggesting involvement of a p53-PUMA-mediated mechanism.

CONCLUSIONS

Dichloroacetate effectively sensitizes most endometrial cancer cell lines to apoptosis via mitochondrial, NFAT-Kv1.5, and PUMA-mediated mechanisms. Further investigation of the cancer therapeutic potential of DCA is warranted.

Molecular determinants of invasion in endometrial cancer

Endometrial carcinoma is the most common gynaecological malignancy in the western world and the most frequent among infiltrating tumours of the female genital tract. Despite the characterisation of molecular events associated with the development of endometrial carcinoma, those associated with the early steps of infiltration and invasion in endometrial cancer are less known. Deep myometrial invasion correlates with more undifferentiated tumours, lymph-vascular invasion, node affectation and decreased global survival. In this review we present an overview of the molecular pathology of myometrial infiltration that defines the initial steps of invasion in endometrial cancer. Down-regulation of E-cadherin as a main player of epithelial to mesenchymal transition, as well as modifications on other molecules involved in cell-cell contacts, render cells with a migratory phenotype. In addition, altered signalling pathways and transcription factors associate with myometrial invasion, histologic grade and metastasis.

The role of matrix metalloproteinases-2, -7 and -9 and ?-catenin in high grade endometrial carcinoma

AIMS

To determine the expression of matrix metalloproteinases (MMPs)-2, -7 and -9 and beta-catenin in uterine serous carcinoma (USC) and endometrioid endometrial carcinoma (EEC) and to investigate any difference in expression between EEC and USC which might explain the mechanism of invasion and aggressive behaviour of USC.

METHODS AND RESULTS

Tissue microarrays were created from the viable central part and from the invasive edge of 20 cases of grade 3 EEC and 73 cases of USC. Immunohistochemistry was performed using antibodies to MMPs-2, -7 and -9 and beta-catenin. MMPs-2, -7 and -9 and beta-catenin were present in both tumour types; there was significantly higher expression of MMPs-2 and -9 in EEC compared with USC and significantly increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC.

CONCLUSIONS

MMPs-2, -7 and -9 and beta-catenin are present in EEC and USC. The increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC is possibly due to increased binding of MMPs secreted by the stromal cells to carcinoma cells, thus equipping the USC carcinoma cells with proteases for invasion.

Transforming growth factor-beta3 increases the invasiveness of endometrial carcinoma cells through phosphatidylinositol 3-kinase-dependent up-regulation of X-linked inhibitor of apoptosis and protein kinase c-dependent induction of matrix metalloproteinase-9

Tumor cells often acquire intrinsic resistance to the growth inhibitory and pro-apoptotic effects of transforming growth factor-beta (TGF-beta); moreover, TGF-beta can confer invasive properties to established tumor cells. In the present study, we show that TGF-beta isoforms (TGF-beta1, TGF-beta2, and TGF-beta3) trigger proper Smad signaling in human endometrial carcinoma cell lines and efficiently inhibit cellular proliferation. These cells, however, exhibit a high degree of resistance to TGF-beta pro-apoptotic effects; we found that this resistant phenotype would be acquired through up-regulation of X-linked inhibitor of apoptosis protein (XIAP) levels. In addition, using RNA interference and pharmacological inhibitors, we show that TGF-beta increases cellular invasiveness via two distinct signaling pathways in endometrial carcinoma cells: phosphatidylinositol 3-kinase/AKT-dependent up-regulation of XIAP and protein kinase C-dependent induction of matrix-metalloproteinase-9 (MMP-9) expression. Additionally, these findings were correlated with clinical observations showing abundant TGF-beta immunoreactivity in human endometrial carcinoma tumors in vivo, extending from the epithelial compartment to the stroma upon acquisition of an invasive phenotype (gradually from grades I to III). Collectively our results describe for the first time a role for TGF-beta3 in tumor invasiveness.

Gelatinases A and B (MMP-2 and MMP-9) in endometrial cancer—MMP-9 correlates to the grade and the stage

OBJECTIVE

Matrix metalloproteinases (MMPs) have been linked to aggressive behavior in several malignancies. Gelatinases (MMP-2 and MMP-9) in particular are prognostic factors in many adeno- and epithelial cancers. However, no conclusive data exist concerning the role of gelatinases in endometrial cancer.

METHODS

Eighty-eight patients with endometrial cancer, treated between 1988 and 1993 in Umeå University Hospital, were included. MMP-2 and MMP-9 proteins were analyzed immunohistochemically from paraffin-embedded tissues by using specific monoclonal antibodies. The staining results were compared to the clinical data.

RESULTS

Fifty-two percent of the cases were positive for MMP-9 and 72% for MMP-2. The overexpression of the proteins of either MMP-2 or MMP-9 was associated with poor survival. The predictive value of MMP-2 expression was most distinct in stage I cancers. An association was found between the positivity of MMP-2 and MMP-9. Only 3% of the cases were highly positive for both gelatinases and 18% of the cases were negative for both MMPs. Both gelatinases correlated to the histological grade. MMP-9 also correlated to the clinical stage of the disease, whereas MMP-2 did not. There was no apparent association with either depth of invasion, menopausal status, or the age of the patient.

CONCLUSION

MMP-2 and MMP-9 could serve as markers for the clinical behavior of endometrial cancer. They may further be linked to a tendency to cancer relapse. Thus, these gelatinases may turn out to be potentially useful in decision making about the need for an adjuvant treatment.

Matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 expression is not regulated by norgestimate or norelgestromin

Steroid hormones regulate endometrial expression of matrix metalloproteinases (MMPs) and their inhibitors. Synthetic progestins are widely used in oral contraceptives and for hormone replacement therapy. To assess whether the synthetic progestins norgestimate and its derivative norelgestromin (17-deacetylnorgestimate) modulate the expression of MMPs, Ishikawa endometrial cancer cells were separately treated with 17 beta-estradiol, 17 alpha-hydroxyprogesterone, norgestimate and norelgestromin. Culture supernatants were assayed for MMPs 2, 3 and 9, and for tissue inhibitors of MMPs (TIMP-1 and TIMP-2) by enzyme-linked immunosorbent assays (ELISAs). No marked modulation of MMP-2 and TIMP-2 expression was observed upon incubation of the cells with the synthetic progestins. By ELISA, neither MMP-3 or MMP-9 nor TIMP-1 immunoreactivity was detected. Interestingly, TIMP-2 expression was down-regulated by 17 beta-estradiol and 17 alpha-hydroxyprogesterone.

Expression of matrix metalloproteinase-26 and tissue inhibitors of metalloproteinases TIMP-3 and -4 in benign endometrium and endometrial cancer

OBJECTIVE

Matrix metalloproteinases (MMPs) and their physiological inhibitors, the tissue inhibitors of MMPs (TIMPs), play a key role in tumor cell invasion, angiogenesis, and growth. The aim of this study was to determine the expression and cellular distribution of MMP-26, TIMP-3, and TIMP-4 in endometrial cancers and benign endometrium throughout the menstrual cycle and the correlation with tumor histological subtype, stage, and grade.

METHODS

Immunohistochemical analysis using polyclonal antibodies generated against pro- and active MMP-26, and mono- and polyclonal antibodies specific to TIMP-3 and TIMP-4, respectively, was performed.

RESULTS

MMP-26, TIMP-3, and TIMP-4 are expressed in endometrial carcinomas (N = 86) and benign endometrium (N = 50) from various stages of the menstrual cycle. Semi-quantitative analysis of staining intensity indicated that endometrial carcinomas expressed more MMP-26, TIMP-3, and TIMP-4 compared to benign endometrium from the postmenopausal period, but not from the secretory phase of the menstrual cycle. The highest staining intensity was associated with endometrial epithelial cells, followed by vascular endothelial cells, myometrial smooth muscle cells, and endometrial stromal cells. Increased staining intensity of MMP-26 and TIMP-3 correlated with grade III tumors and MMP-26 and TIMP-4 with the depth of myometrial invasion in tumors histologically characterized as endometrioid adenocarcinoma, clear-cell, and papillary serous carcinoma staged/graded based on FIGO criteria.

CONCLUSION

MMP-26 and TIMP-4 are expressed in endometrium and endometrial carcinoma and their elevated expression and correlation with myometrial invasion suggests that MMP-26 and TIMP-4 may play a key role in endometrial tumor progression.