Tissue factor pathway inhibitor-2 silencing promotes hepatocellular carcinoma cell invasion in vitro

Tissue factor pathway inhibitor-2 (TFPI-2)-an underappreciated partaker in cancer and metastasis

The coagulation system is known to play an important role in cancer development and metastasis, but the precise mechanisms by which it does so remain incompletely understood. With this in mind, we provide an updated overview of the effects of TFPI-2, a protease inhibitor, on cancer development and metastasis. TFPI-2 interacts with the thrombin cascade and also employs other mechanisms to suppress cancer growth and dissemination, which include extracellular matrix stabilization, promotion of caspase-mediated cell apoptosis, inhibition of angiogenesis and transduction of intracellular signals. Down-regulation of TFPI-2 expression is well documented in numerous types of neoplasms, mainly via promoter methylation. However, the exact role of TFPI-2 in cancer progression and possible approaches to up-regulate TFPI-2 expression warrant further studies. Strategies to reactivate TFPI-2 may represent a promising direction for future anticancer studies and therapy development.

Toward an understanding of tissue factor pathway inhibitor-2 as a novel serodiagnostic marker for clear cell carcinoma of the ovary

AIMS

Tissue factor pathway inhibitor (TFPI)-2 has recently emerged as a serodiagnostic marker for patients with epithelial ovarian cancer (EOC), especially clear cell carcinoma (CCC). This review discusses the biological properties of TFPI-2 and why serum levels are elevated in CCC patients.

METHODS

A comprehensive literature search was conducted in PubMed up until March, 2021.

RESULTS

TFPI-2 is a Kunitz-type protease inhibitor and negatively regulates the enzymatic activities, such as plasmin. TFPI-2 has been characterized as a tumor suppressor gene and was frequently downregulated through promoter hypermethylation in various human cancers. In contrast, TFPI-2 was overexpressed only in CCC. TFPI-2 may be involved in the pathophysiology of CCC, possibly through regulation of coagulation system, stabilization of extracellular matrix (ECM), and induction of intracellular signal transduction. TFPI-2 suppresses tissue factor-induced hypercoagulation in a hypoxic environment. TFPI-2, secreted by CCC cells, platelets, and adjacent vascular endothelial cells, may suppress tumor growth and invasion through ECM remodeling. Nuclear TFPI-2 may suppress matrix metalloproteinase production via transcription factors and modulate caspase-mediated cell apoptosis. CCC cells may upregulate the TFPI-2 expression to adapt to survival in the demanding environment. TFPI-2 is secreted by CCC cells and enters the systemic circulation, resulting in elevated blood levels.

DISCUSSION

Serum TFPI-2 reflects the overexpression of TFPI-2 in CCC tissues and is a potential serodiagnostic marker. Further research is needed to explore the expression, clinical significance, biological function, and potential mechanism of TFPI-2 in CCC.

Overexpression of tissue factor pathway inhibitor 2 attenuates trophoblast proliferation and invasion in preeclampsia

Pre-eclampsia (PE) is a disorder of pregnancy characterized by proteinuria and high blood pressure, affecting 2-8% of pregnancies worldwide. Previous studies have shown that PE is closely associated with trophoblast cell dysfunction. Here, we investigated the role of tissue factor pathway inhibitor-2 (TFPI-2) in regulating the biological processes of trophoblast cells. The TFPI-2 levels in plasma samples and placental tissues were tested by ELISA, immunohistochemistry, qRT-PCR, and western blot. HTR8/Svneo cell line was used to simulate the primary trophoblast cells and H/R culture was applied to mimic the oxidative stress state of PE. MTT assay, Annexin V/propidium iodide (PI) apoptosis assay, and transwell assay were used to determine the cell proliferation, apoptosis, and invasion. The expression levels of matrix metalloproteinases (MMPs) were evaluated by western blot. The expression of TFPI-2 was remarkably up-regulated in both the serum and placenta of PE patients. Hypoxia/reoxygenation increased the expression of TFPI-2 in HTR-8/SVneo cell line. TFPI-2 promoted that cell proliferation and inhibited the cell apoptosis of HTR8/SVneo cells in H/R condition. In addition, downregulation of TFPI-2 increased the cell invasion and the expression of MMP2 and MMP9. This study reveals that TFPI-2 plays a crucial role in monitoring the biological function of trophoblast cells, which might provide theoretical basis and therapeutic targets for the treatment of PE.

Low abundance of TFPI-2 by both promoter methylation and miR-27a-3p regulation is linked with poor clinical outcome in gastric cancer

BACKGROUND

The tumor suppressor role of tissue factor pathway inhibitor 2 (TFPI-2) has been reported in various tumors. The present study aimed to improve the understanding of the oncogenic properties of TFPI-2 in gastric cancer.

METHODS

Relative expression of TFPI-2 was determined by a real-time polymerase chain reaction (PCR) and western blotting, respectively. Cell viability was measured via a cell counting kit-8 assay and proliferation was evaluated by a colony formation assay. Cell apoptosis was assessed with a caspase-3 activity kit and invasion was evaluated by a transwell chamber assay. The methylation level of TFPI-2 promoter was assayed by methylation-specific PCR. The regulatory effect of miR-27a-3p on TFPI-2 was analyzed with a luciferase reporter assay. The direct association between miR-27a-3p and TFPI-2 was shown by biotin-labelling pulldown.

RESULTS

TFPI-2 was down-regulated in gastric cancer, which associated with an unfavorable prognosis clinically. Ectopic introduction of TFPI-2 greatly compromised cell viability, colony formation and invasive capacity, and also induced cell apoptosis simultaneously. The promoter region of TFPI-2 was extensively methylated in gastric cancer tissues compared to normal tissues, suggesting the epigenetic inhibition of TFPI-2 expression. We further identified that TFPI-2 functioned as sponge RNA against miR-27a-3p. Most importantly, miR-27a-3p-specific inhibitor significantly exerted a tumor suppressor function akin to TFPI-2 itself, and the anti-tumoral activities were completely abolished by TFPI-2 knockdown.

CONCLUSIONS

We found that the epigenetically suppressed TFPI-2 compromised sponging effects with respect to miR-27a-3p in gastric cancer, which consequently and mechanistically contributed to the tumor biology of gastric cancer.

Tissue factor pathway inhibitor 2 suppresses the growth of thyroid cancer cells through by induction of apoptosis

BACKGROUND

Tissue factor pathway inhibitor 2 (TFPI-2) has been recently identified as a tumor suppressor gene in several human cancers, whereas its role in thyroid cancer has been unclear.

METHODS

The TFPI-2 protein level in thyroid cancer tissues and cell lines (8305C and B-CPAP) were examined using immunohistochemistry and immunoblotting. The TFPI-2 promoter methylation was examined using methylation-specific polymerase chain reaction (MSP). Lentivirus containing TFPI-2 cDNA (Lenti-TFPI-2) was constructed to elevate TFPI-2 expression in 8305C and B-CPAP cells. The effects of Lenti-TFPI-2 on cell proliferation in vitro and in vivo were evaluated by MTT assay and mouse xenograft model. Annexin V/PI double staining assay was performed to detect the effect of Lenti-TFPI-2 on cell apoptosis.

RESULTS

TFPI-2 protein level were decreased in cancer tissues and lymph node metastasis, and TFPI-2 protein level is positively associated with survival time. The promoter of TFPI-2 is hypermethylated in cancer tissues. TFPI-2 mRNA and protein levels were abundant in normal human thyroid follicular cell line Nthy-ori 3-1 cells, whereas they were decreased in 8305C and B-CPAP cells. pcDNA-TFPI-2 elevated TFPI-2 mRNA and protein in 8305C and B-CPAP cells. TFPI-2 overexpression suppressed proliferation and induced apoptosis of 8305C and B-CPAP cells.

CONCLUSIONS

TFPI-2 inactivation may play a role in thyroid cancer tumorigenesis and development. TFPI-2 overexpression suppressed cell proliferation through induction of cell apoptosis, suggesting that TFPI-2 may serve as a novel and effective target for thyroid cancer therapy.

Physcion Synergistically Enhances the Cytotoxicity of Sorafenib in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common human malignancy. Physcion is a naturally occurring anthraquinone derivative found in plant and marine sources. Our previous studies have indicated that physcion could suppress tumor growth and induce apoptosis in HCC. This study was aimed to investigate the effect of a combination of physcion and sorafenib on HCC. Our findings indicated that physcion could significantly augment the antiproliferative and proapoptotic activities of sorafenib in vitro and in vivo. Mechanistically, the synergistic effect correlates with physcion-induced suppression of Notch3/AKT signaling. This preclinical evidence highlights the potential application of physcion in the treatment of HCC. Anat Rec, 302:2171-2177, 2019. © 2019 American Association for Anatomy.

Methylation of tissue factor pathway inhibitor 2 as a prognostic biomarker for hepatocellular carcinoma after hepatectomy

BACKGROUND AND AIM

Methylation of tissue factor pathway inhibitor 2 (TFPI2) gene has been detected in hepatocellular carcinoma (HCC). However, the clinicopathologcial significance and prognostic value of TFPI2 methylation in HCC remains largely unknown. This study aimed to investigate the prognostic value of TFPI2 methylation in HCC after hepatectomy.

METHODS

Methylation status of TFPI2 gene was examined in 178 surgical specimens of HCC and 20 normal liver samples using methylation-specific polymerase chain reaction.

RESULTS

Methylation of TFPI2 gene was detected in 44.9% (80 of 178) of primary HCC samples, 10.7% (19 of 178) of the corresponding non-tumorous liver samples, and 5.0% (1/20) of the normal liver samples. The mRNA concentrations of TFPI2 in primary HCC tissues were significantly lower than those in corresponding non-tumorous liver tissues and those in normal liver tissues. TFPI2 methylation was significantly associated with higher TNM stage. Patients with TFPI2 methylation demonstrated a significantly poorer prognosis than those without TFPI2 methylation for both overall survival and disease-free survival (P < 0.001, respectively). Multivariate analyses confirmed that TFPI2 methylation was an independent prognostic factor for both overall survival (P = 0.002) and disease-free survival (P = 0.000) in HCC after hepatectomy. Moreover, TFPI2 methylation was found to be the only independent predictor for early tumor recurrence of HCC after resection based on multivariate analysis (P = 0.002).

CONCLUSIONS

Methylation of TFPI2 predicts high risk of advanced tumor stage, early tumor recurrence, and poor prognosis, and it could be a potential prognostic biomarker in patients with HCC after hepatectomy.

miR-302b suppresses cell invasion and metastasis by directly targeting AKT2 in human hepatocellular carcinoma cells

MicroRNAs (miRNAs) have been shown to play essential roles in regulating the activity of human hepatocellular carcinoma (HCC) cells, thereby contributing to the suppression of invasion and metastasis. In this study, using gain and loss of function assays, we demonstrated that miR-302b was frequently down-regulated in clinical HCC specimens, as compared with 15 corresponding adjacent normal tissues. Overexpression of miR-302b suppressed HCC cell invasion and metastasis. Regulation of NF-κB and matrix metalloproteinase (MMP)-2 expression by miR-302b was mediated via AKT2 in SMMC-7721 cells. Silencing AKT2 produced effects similar to those of miR-302b overexpression, which included inhibiting SMMC-7721 cell invasion and metastasis and dereasing NF-κB and MMP-2 expression. Furthermore, overexpression of AKT2 attenuated the effects of miR-302b overexpression. Taken together, our findings indicate that miR-302b inhibits SMMC-7721 cell invasion and metastasis by targeting AKT2, suggesting that miR-302b might represent a potential therapeutic target for HCC intervention.