Progesterone utilizes distinct membrane pools of tissue factor to increase coagulation and invasion and these effects are inhibited by TFPI

TFPI inhibits breast cancer progression by suppressing ERK/p38 MAPK signaling pathway

BACKGROUND

Tissue factor pathway inhibitor-1 (TFPI) is a serine protease inhibitor, which is responsible for inactivating TF-induced coagulation. Recently, increasing studies revealed that TFPI was lowly expressed in tumor cells and exhibited the antitumor activity.

OBJECTIVE

The aim of this study was to explore the role and underlying molecular mechanisms of TFPI in breast cancer.

METHODS

The expression and prognostic value of TFPI were analyzed using UALCAN and Kaplan-Meier plotter website. The expression level of TFPI in breast cancer tissues and cells was examined by immunohistochemistry (IHC) and western blot analysis, respectively. Cellular proliferation was evaluated by CCK-8 and colony formation assays. Cell migration and invasion were determined by transwell assay. The methylation level of TFPI promoter was determined by methylation-specific PCR.

RESULTS

TFPI expression was significantly lower in breast cancer tissues and cells compared to normal breast tissues and normal breast cells. Patients with low TFPI levels showed worse overall survival (OS). Furthermore, overexpression of TFPI significantly inhibited the proliferation, migration and invasion of breast cancer cells. Conversely, knockdown of TFPI promoted the proliferation, migration and invasion of breast cancer cells. Mechanistically, TFPI inhibited the ERK/p38 MAPK signaling pathway in breast cancer. Moreover, DNA hypermethylation of TFPI promoter was responsible for the downregulation of TFPI in breast cancer cells.

CONCLUSION

TFPI inhibited breast cancer cell proliferation, migration and invasion through inhibition of the ERK/p38 MAPK signaling pathway, suggesting that TFPI may serve as a novel prognostic biomarker and therapeutic target for breast cancer.

Coagulation Factor Xa Promotes Solid Tumor Growth, Experimental Metastasis and Endothelial Cell Activation

Hypercoagulable state is linked to cancer progression; however, the precise role of the coagulation cascade is poorly described. Herein, we examined the contribution of a hypercoagulative state through the administration of intravenous Coagulation Factor Xa (FXa), on the growth of solid human tumors and the experimental metastasis of the B16F10 melanoma in mouse models. FXa increased solid tumor volume and lung, liver, kidney and lymph node metastasis of tail-vein injected B16F10 cells. Concentrating on the metastasis model, upon coadministration of the anticoagulant Dalteparin, lung metastasis was significantly reduced, and no metastasis was observed in other organs. FXa did not directly alter proliferation, migration or invasion of cancer cells in vitro. Alternatively, FXa upon endothelial cells promoted cytoskeleton contraction, disrupted membrane VE-Cadherin pattern, heightened endothelial-hyperpermeability, increased inflammatory adhesion molecules and enhanced B16F10 adhesion under flow conditions. Microarray analysis of endothelial cells treated with FXa demonstrated elevated expression of inflammatory transcripts. Accordingly, FXa treatment increased immune cell infiltration in mouse lungs, an effect reduced by dalteparin. Taken together, our results suggest that FXa increases B16F10 metastasis via endothelial cell activation and enhanced cancer cell-endothelium adhesion advocating that the coagulation system is not merely a bystander in the process of cancer metastasis.

Impact of progestogens on hemostasis

Combined hormonal contraception containing estrogen and progestogen and postmenopausal hormone therapy with estrogen ± progestogen are reported risk factors for venous thrombosis. The thrombotic risk varies by estrogen dose and type of progestogen. Estrogen combined with "newer generation" progestogens in combined oral contraceptives may have higher thrombotic risk than estrogen combined with older generation progestogens. Among postmenopausal women thrombotic risk also varies by type of hormone and mode of delivery. Although the risk of thrombosis with the different hormonal compounds is uncertain, it has definitely been attributed to the pharmacological effect of the hormones on hemostasis. Animal and cell culture studies have demonstrated the pharmacodynamics of progestogens with respect to hemostasis. Extrapolation from these studies to clinical conditions and further to clinical end points such as cardiovascular disease is, however, controversial. Few clinical studies have focused on the effect of progestogen only therapy on the hemostatic system in vivo. Most of the current knowledge regarding the in vivo effect of progestogens on hemostasis is obtained from studies with combined contraceptives. These results obviously reflect the combined influence of both estrogen and progestogen on hemostasis, and extrapolation to progestogen-only conditions is challenging. This paper discusses the pharmacodynamics of progestogens in relation to the hemostatic system, addressing results obtained in animal and cell culture studies and in clinical studies employing progestogen-only and combined oral contraceptives. The compiled results suggest that the major effect of progestogens on hemostasis is related to alterations in platelet function and the tissue factor pathway of coagulation. More studies focusing on these topics are warranted.

Role of the short isoform of the progesterone receptor in breast cancer cell invasiveness at estrogen and progesterone levels in the pre- and post-menopausal ranges

Overexpression of the progesterone receptor (PR) isoform A (PR-A) is a negative prognosticator for estrogen receptor (ER)-positive breast cancer but in vitro studies have implicated PR-B in progestin-induced invasiveness. As estrogen is known to suppress invasiveness and tumor progression and as the in vitro studies were conducted in models that either lacked ER or excluded estrogen, we examined the role of PR isoforms in the context of estrogen signaling. Estrogen (< 0.01nM) strongly suppressed invasiveness in various ER+ model cell lines. At low (< 1nM) concentrations, progestins completely abrogated inhibition of invasiveness by estrogen. It was only in a higher (5 nM - 50 nM) concentration range that progestins induced invasiveness in the absence of estrogen. The ability of low dose progestins to rescue invasiveness from estrogen regulation was exclusively mediated by PR-A, whereas PR-B mediated the estrogen-independent component of progestin-induced invasiveness. Overexpression of PR-A lowered the progestin concentration needed to completely rescue invasiveness. Among estrogen-regulated genes, progestin/PR-A counter-regulated a distinctive subset, including breast tumor progression genes (e.g., HES1, PRKCH, ELF5, TM4SF1), leading to invasiveness. In this manner, at relatively low hormone concentrations (corresponding to follicular stage and post-menopausal breast tissue or plasma levels), progesterone influences breast cancer cell invasiveness by rescuing it from estrogen regulation via PR-A, whereas at higher concentrations the hormone also induces invasiveness independent of estrogen signaling, through PR-B. The findings point to a direct functional link between PR-A and progression of luminal breast cancer in the context of the entire range of pre- and post-menopausal plasma and breast tissue hormone levels.

Breast cancer phenotypes regulated by tissue factor-factor VII pathway: Possible therapeutic targets

Breast cancer is a leading cause of cancer death in women, worldwide. Fortunately, breast cancer is relatively chemosensitive, with recent advances leading to the development of effective therapeutic strategies, significantly increasing disease cure rate. However, disease recurrence and treatment of cases lacking therapeutic molecular targets, such as epidermal growth factor receptor 2 and hormone receptors, referred to as triple-negative breast cancers, still pose major hurdles in the treatment of breast cancer. Thus, novel therapeutic approaches to treat aggressive breast cancers are essential. Blood coagulation factor VII (fVII) is produced in the liver and secreted into the blood stream. Tissue factor (TF), the cellular receptor for fVII, is an integral membrane protein that plays key roles in the extrinsic coagulation cascade. TF is overexpressed in breast cancer tissues. The TF-fVII complex may be formed in the absence of injury, because fVII potentially exists in the tissue fluid within cancer tissues. The active form of this complex (TF-fVIIa) may stimulate the expression of numerous malignant phenotypes in breast cancer cells. Thus, the TF-fVII pathway is a potentially attractive target for breast cancer treatment. To date, a number of studies investigating the mechanisms by which TF-fVII signaling contributes to breast cancer progression, have been conducted. In this review, we summarize the mechanisms controlling TF and fVII synthesis and regulation in breast cancer cells. Our current understanding of the TF-fVII pathway as a mediator of breast cancer progression will be also described. Finally, we will discuss how this knowledge can be applied to the design of future therapeutic strategies.

TFPI1 mediates resistance to doxorubicin in breast cancer cells by inducing a hypoxic-like response

Thrombin and hypoxia are important players in breast cancer progression. Breast cancers often develop drug resistance, but mechanisms linking thrombin and hypoxia to drug resistance remain unresolved. Our studies using Doxorubicin (DOX) resistant MCF7 breast cancer cells reveals a mechanism linking DOX exposure with hypoxic induction of DOX resistance. Global expression changes between parental and DOX resistant MCF7 cells were examined. Westerns, Northerns and immunocytochemistry were used to validate drug resistance and differentially expressed genes. A cluster of genes involved in the anticoagulation pathway, with Tissue Factor Pathway Inhibitor 1 (TFPI1) the top hit, was identified. Plasmids overexpressing TFPI1 were utilized, and 1% O₂ was used to test the effects of hypoxia on drug resistance. Lastly, microarray datasets from patients with drug resistant breast tumors were interrogated for TFPI1 expression levels. TFPI1 protein levels were found elevated in 3 additional DOX resistant cells lines, from humans and rats, indicating evolutionarily conservation of the effect. Elevated TFPI1 in DOX resistant cells was active, as thrombin protein levels were coincidentally low. We observed elevated HIF1α protein in DOX resistant cells, and in cells with forced expression of TFPI1, suggesting TFPI1 induces HIF1α. TFPI1 also induced c-MYC, c-SRC, and HDAC2 protein, as well as DOX resistance in parental cells. Growth of cells in 1% O₂ induced elevated HIF1α, BCRP and MDR-1 protein, and these cells were resistant to DOX. Our in vitro results were consistent with in vivo patient datasets, as tumors harboring increased BCRP and MDR-1 expression also had increased TFPI1 expression. Our observations are clinically relevant indicating that DOX treatment induces an anticoagulation cascade, leading to inhibition of thrombin and the expression of HIF1α. This in turn activates a pathway leading to drug resistance.

Changes in coagulation and fibrinolytic indices in women with polycystic ovarian syndrome undergoing controlled ovarian hyperstimulation

Background. Polycystic ovarian syndrome (PCOS) women undergoing in vitro fertilization and embryo transfer (IVF-ET) treatment always attain a low cumulative pregnancy rate disaccording with the satisfactory number of oocytes. Objective. We aim to evaluate the status of coagulation and fibrinolytic system in PCOS patients undergoing controlled ovarian hyperstimulation (COH) process. Method. Of the 97 women, 30 patients with PCOS composed the study group; 67 women of child-bearing age with normal endocrine function composed the control group. All participants underwent GnRH agonist standard long protocol, and plasma HCY, FVIII, FX, and D-dimer levels as well as hormone parameters were measured at day of full downregulation, hCG priming, and embryos transfer. Results. On day of full downregulation, FX levels were significantly higher in PCOS group (P < 0.01). On hCG priming day, FX and estrogen levels in PCOS group were higher than in the control group and FVIII levels were significantly lower on day of embryos transfer whereas FX and E2 levels were significantly higher in PCOS group. Conclusion. Hypercoagulable state during peri-implantation phase would probably lead to poor microcirculation of endometrium and be one of the most important disadvantages of successful implantation and subsequent clinical pregnancy.

Progesterone promotes focal adhesion formation and migration in breast cancer cells through induction of protease-activated receptor-1

Progesterone and progestins have been demonstrated to enhance breast cancer cell migration, although the mechanisms are still not fully understood. The protease-activated receptors (PARs) are a family of membrane receptors that are activated by serine proteases in the blood coagulation cascade. PAR1 (F2R) has been reported to be involved in cancer cell migration and overexpressed in breast cancer. We herein demonstrate that PAR1 mRNA and protein are upregulated by progesterone treatment of the breast cancer cell lines ZR-75 and T47D. This regulation is dependent on the progesterone receptor (PR) but does not require PR phosphorylation at serine 294 or the PR proline-rich region mPRO. The increase in PAR1 mRNA was transient, being present at 3  h and returning to basal levels at 18  h. The addition of a PAR1-activating peptide (aPAR1) to cells treated with progesterone resulted in an increase in focal adhesion (FA) formation as measured by the cellular levels of phosphorylated FA kinase. The combined but not individual treatment of progesterone and aPAR1 also markedly increased stress fiber formation and the migratory capacity of breast cancer cells. In agreement with in vitro findings, data mining from the Oncomine platform revealed that PAR1 expression was significantly upregulated in PR-positive breast tumors. Our observation that PAR1 expression and signal transduction are modulated by progesterone provides new insight into how the progestin component in hormone therapies increases the risk of breast cancer in postmenopausal women.

Effects of omega-3 fatty acids on progestin stimulation of invasive properties in breast cancer

Clinical studies have shown that progestins increase breast cancer risk in hormone replacement therapy, while we and others have previously reported that progestins stimulate invasive properties in progesterone receptor (PR)-rich human breast cancer cell lines. Based on others' reports that omega-3 fatty acids inhibit metastatic properties of breast cancer, we have reviewed the literature for possible connections between omega-3 fatty-acid-driven pathways and progestin-stimulated pathways in an attempt to suggest theoretical mechanisms for possible omega-3 fatty acid inhibition of progestin stimulation of breast cancer invasion. We also present some data suggesting that fatty acids regulate progestin stimulation of invasive properties in PR-rich T47D human breast cancer cells, and that an appropriate concentration of the omega-3 fatty acid eicosapentaenoic acid inhibits progestin stimulation of invasive properties. It is hoped that focus on the inter-relationship between pathways by which omega-3 fatty acids inhibit and progestins stimulate breast cancer invasive properties will lead to further in vitro, in vivo, and clinical studies testing the hypothesis that omega-3 fatty acids can inhibit progestin stimulation of invasive properties in breast cancer, and ameliorate harmful effects of progestins which occur in combined progestin-estrogen hormone replacement therapy.