Unveiling heterogeneity and prognostic markers in ductal breast cancer through single-cell RNA-seq.

BACKGROUND: Breast cancer (BC) is a heterogeneous disease, with the ductal subtype exhibiting significant cellular diversity that influences prognosis and response to treatment. Single-cell RNA sequencing data from the GEO database were utilized in this study to investigate the underlying mechanisms of cellular heterogeneity and to identify potential prognostic markers and therapeutic targets. METHODS: Bioinformatics analysis was conducted using R packages to analyze the single-cell sequencing data. The presence of highly variable genes and differences in malignant potency within the same BC samples were examined. Differential gene expression and biological function between Type 1 and Type 2 ductal epithelial cells were identified. Lasso regression and Cox proportional hazards regression analyses were employed to identify genes associated with patient prognosis. Experimental validation was performed in vitro and in vivo to confirm the functional relevance of the identified genes. RESULTS: The analysis revealed notable heterogeneity among BC cells, with the presence of highly variable genes and differences in malignant behavior within the same samples. Significant disparities in gene expression and biological function were identified between Type 1 and Type 2 ductal epithelial cells. Through regression analyses, CYP24A1 and TFPI2 were identified as pivotal genes associated with patient prognosis. Kaplan-Meier curves demonstrated their prognostic significance, and experimental validation confirmed their inhibitory effects on malignant behaviors of ductal BC cells. CONCLUSION: This study highlights the cellular heterogeneity in ductal subtype breast cancer and delineates the differential gene expressions and biological functions between Type 1 and Type 2 ductal epithelial cells. The genes CYP24A1 and TFPI2 emerged as promising prognostic markers and therapeutic targets, exhibiting inhibitory effects on BC cell malignancy in vitro and in vivo. These findings offer the potential for improved BC management and the development of targeted treatment strategies.

Tissue factor pathway inhibitor 2 as a serum biomarker for endometrial cancer: a single-center retrospective study.

BACKGROUND: Endometrial cancer is the most common gynecological malignancy; however, there is no useful blood diagnostic biomarker. This study aimed to determine the utility of tissue factor pathway inhibitor 2 (TFPI2), a biomarker of ovarian cancer, as a diagnostic marker for endometrial cancer. METHODS: We examined serum TFPI2 levels in patients with endometrial cancer (n = 328) compared to those in healthy controls (n = 65) and evaluated the performance of serum TFPI2 levels as a diagnostic marker. We investigated the clinicopathological characteristics of patients with TFPI2-negative and TFPI2-positive endometrial cancer. Using immunohistochemistry (IHC), we examined TFPI2 expression in tumor tissues of 105 patients with type II endometrial carcinoma and evaluated the correlation between serum and tissue TFPI2 positivity. RESULTS: Patients with endometrial cancer had significantly higher serum TFPI2 levels than controls (196.7 pg/mL vs. 83.3 pg/mL; p < 0.001). The sensitivity and specificity were 54.3% and 95.4%, respectively (cutoff value, 191 pg/mL). Serum TFPI2 levels were significantly elevated along with the stage progression (stage I, 189.6 pg/mL; stage III, 230.9 pg/mL; stage IV, 312.5 pg/mL; p < 0.001). Patients with high-risk histology showed significantly elevated serum TFPI2 levels than those with low-risk histology (220.8 pg/mL vs. 187.7 pg/mL; p < 0.001). The positivity rate for TFPI2 was the highest among tumor markers, including CA125, CA19-9, and CEA. Serum TFPI2 and CA125 levels were almost independent (r = 0.203, p < 0.001), and the combined sensitivity increased to 58.8%. The 5-year survival rate was significantly worse in TFPI2-positive patients (≥ 191 pg/mL, n = 178) than in TFPI2-negative patients (< 191 pg/mL, n = 150) (hazard ratio, 8.22; 95% confidence interval, 2.49-27.1; p < 0.001). TFPI2 immunostaining revealed that 37.1% (39/105) of the samples were positive for TFPI2, with an IHC score of > 0. There was no significant difference in the immunostaining score according to histological type. Serum TFPI2 levels and immunostaining score showed poor agreement (kappa coefficient, -0.039). CONCLUSIONS: The serum TFPI2 level is a promising marker for diagnosing and predicting the prognosis of endometrial cancer. No correlation exists between serum and tissue TFPI2 levels. Further multicenter clinical trials are needed to test the utility of TFPI2 as a diagnostic marker.

FTO overexpression expedites wound healing and alleviates depression in burn rats through facilitating keratinocyte migration and angiogenesis via mediating TFPI-2 demethylation.

Burn injury is a serious traumatic injury that leads to severe physical and psychosocial impairment. Wound healing after burn injury is a substantial challenge in medical community. This study investigated the biological effects of the demethylase fat mass and obesity-associated protein (FTO) on burn injury. FTO protein level in burn skin tissues of patients was measured with Western blot assay. Keratinocytes (HaCaT cells) were given heat stimulation to induce an in vitro burn injury model, and then transfected with overexpression plasmids of FTO (pcDNA-FTO) or small interfering RNA against FTO (si-FTO). Cell proliferation, migration, and angiogenesis in keratinocytes were evaluated with CCK-8, Transwell, and tube formation assays, respectively. Tissue factor pathway inhibitor-2 (TFPI-2) m6A methylation level was detected with MeRIP­qPCR assay. Then rescue experiments were conducted to explore the effects of FTO/TFPI-2 axis on keratinocyte functions. Lentivirus carrying FTO overexpression plasmids was injected into a burn rat model to detect its effects on wound healing and depressive-like behaviors in burn rats. FTO was downregulated in burn skin and heat-stimulated keratinocytes. FTO prominently augmented proliferation, migration and angiogenesis in heat-stimulated keratinocytes, while FTO knockdown showed the opposite results. FTO inhibited TFPI-2 expression by FTO-mediated m6A methylation modification. TFPI-2 overexpression abrogated FTO mediated enhancement of proliferation, migration and angiogenesis in keratinocytes. Additionally, FTO overexpression accelerated wound healing and improved depressive-like behaviors in burn rat model. FTO prominently augmented proliferation, migration and angiogenesis in heat-stimulated keratinocytes though inhibiting TFPI-2, and then improved wound healing and depressive-like behaviors.

Curcumin inhibits the invasion and migration of pancreatic cancer cells by upregulating TFPI-2 to regulate ERK- and JNK-mediated epithelial-mesenchymal transition.

PURPOSE: Pancreatic cancer (PC) is one of the most deadly human malignancies. Curcumin is a natural polyphenolic compound with wide-ranging pharmacological effects. Growing evidence suggests that curcumin has anticancer activity against PC, but the mechanism remains incompletely elucidated. This study aimed to investigate the effects and mechanisms of curcumin on the invasion and migration of PC cells. METHODS: Effect of curcumin on tissue factor pathway inhibitor (TFPI)-2 mRNA expression in PC cells was initially identified using qRT-PCR. Cytotoxicity of curcumin was assessed with MTT assays and IC50 was calculated. Involvement of ERK and JNK pathways, as well as protein expression of TFPI-2 and epithelial-mesenchymal transition (EMT)-related markers, were detected using immunoblotting. Invasion and migration of PC cells were examined using Transwell assays. TFPI-2 expression was manipulated by transfection with siRNA and shRNA. Rescue assays were used to validate the effect of curcumin on cell invasion and migration via TFPI-2. RESULTS: Curcumin increased the expression of TFPI-2 mRNA and protein in PC cells and attenuated cell invasion and migration. Curcumin also inhibited ERK and JNK pathways and EMT in PC cells. Knockdown of TFPI-2 partially reversed the inhibition of ERK and JNK pathways and EMT by curcumin. Mechanistically, curcumin upregulated TFPI-2, thereby inhibiting the ERK and JNK pathways, leading to the inhibition of EMT in PC cells. CONCLUSION: Collectively, curcumin inhibits ERK- and JNK-mediated EMT through upregulating TFPI-2, which in turn suppresses the migration and invasion of PC cells. These findings provide new insights into the antitumor mechanism of curcumin.

TFPI2 suppresses the interaction of TGF-ß2 pathway regulators to promote endothelial-mesenchymal transition in diabetic nephropathy.

Endothelial-mesenchymal transition (EndMT) is an important source of myofibroblasts, but also contributes to the progression of diabetic nephropathy (DN). By several differential gene expression analyses from the Gene Expression Omnibus (GEO) database, the tissue factor pathway inhibitor 2 (TFPI2) gene, known as a tumor suppressor, was shown to be dysregulated in DN; however, the potential role and regulatory mechanism of TFPI2 in DN are unclear. Here, we found abnormal upregulation of TFPI2 in the renal cortex of diabetic mice, accompanied by impaired renal function. We also injected a single dose of adeno-associated virus (AAV)2 carrying shRNA targeting TFPI2 intravenously into these mice and found that knockdown of TFPI2 improved renal function and reduced renal fibrosis and cell apoptosis in experimental DN. Furthermore, hyperglycemia-induced EndMT was inhibited in the absence of TFPI2, as evidenced by increased expression of endothelial markers (VE-cadherin and CD31) and decreased expression of mesenchymal markers (α-SMA, desmin, and FSP-1). To further explore the mechanism in vitro, human renal glomerular endothelial cells (hRGECs) were incubated in the presence of high glucose or transforming growth factor beta (TGF-ß)2. TFPI2 deficiency inhibited high glucose-induced cell apoptosis and TGF-ß2-induced EndMT in hRGECs, while overexpression of TFPI2 had the opposite effects. Importantly, TGF-ß2 is a crucial driver of EndMT, and we found that TFPI2 promoted TGF-ß2/Smad signaling activation by interferring the interaction of TGF-ß pathway regulators (SMURF2 with SMAD7). Our results show that TFPI2 regulates EndMT and the TGF-ß2 signaling pathway and is a potential promoter of DN pathogenesis.

Downregulated DUXAP8 lncRNA impedes trophoblast cell proliferation and migration by epigenetically upregulating TFPI2 expression.

BACKGROUND: Preeclampsia (PE), a pregnancy complication characterized by new-onset hypertension and proteinuria during the second trimester, is the leading cause of neonatal and maternal morbidity and mortality. In the etiology of PE, failure of uterine spiral artery remodeling may be related to functioning abnormally of trophoblast cells, leading to the occurrence and progression of PE. Recently, long noncoding RNAs (lncRNAs) have been reported to play critical roles in PE nowadays. This study aimed to investigate the expression and functions of the TFPI2 pathway-related lncRNA DUXAP8. METHODS: DUXAP8 expression in the placenta from pregnancies was examined using qPCR. Then, the in vitro functions of DUXAP8 were investigated through MTT, EdU, colony, transwell, and flow cytometry experiments. The downstream gene expression profiles were assessed using RNA transcriptome sequencing analysis and verified using qPCR and western blot. Furthermore, Immunoprecipitation (RIP), chromatin immunoprecipitation (CHIP) and fluorescence in situ hybridization (FISH) were used to detect the interaction between lncDUXAP8/EZH2/TFPI2. RESULTS: The expression of lncRNA DUXAP8 in placenta of patients with eclampsia was significantly decreased. After knockout of DUXAP8, the proliferation and migration of trophoblasts were significantly decreased, and the percentage of apoptosis was increased. Flow cytometry showed that low expression of DUXAP8 increased the accumulation of cells in G2/M phase, while overexpression of DUXAP8 had the opposite effect. We also proved that DUXAP8 epigenetically inhibited TFPI2 expression by recruiting EZH2 and mediating H3K27me3 modification. CONCLUSION: Together, these resulting data clarify that aberrant expression of DUXAP8 is involved in the potential PE development and progress. Unraveling the role of DUXAP8 will provide novel insights into the pathogenesis of PE.

Integrative analyses of RNA-seq and ChIP-seq Reveal MITF as a Target Gene of TFPI-2 in MDA231 Cells.

Breast cancer is the most prevalent cancer in female patients worldwide. Tissue factor pathway inhibitor 2 (TFPI-2) is identified as an important tumor suppressor in various cancers. Recent studies have shown that TFPI-2 translocates into the nucleus, where it modulates the transcription of the matrix metalloproteinase-2 (MMP-2) gene. However, its biological role and molecular mechanisms in the progression of breast cancer remain unclear. In this study, we identified 5125 differentially expressed genes (DEGs) from RNA sequencing (RNA-seq) in TFPI-2-overexpressing MDA231 cells compared with control cells. Gene ontology and Kyoto encyclopedia of genes and genomes (KEGG) analysis shown that cell cycle, cell differentiation, proteoglycans in cancer, and pathways associated with cancer were highly enriched in downregulated DEGs. Integration of the RNA-seq and ChIP-sequencing (ChIP-seq) data identified 73 genes directly controlled by TFPI-2 in MDA231 cells. Among them, melanocyte inducing transcription factor (MITF) gene expression was repressed by TFPI-2, which was further verified by a luciferase reporter assay and ChIP-quantitative PCR. Our study provides evidence of a novel role of TFPI-2 in human breast cancer involving targeting of the MITF.

The methylation of SDC2 and TFPI2 defined three methylator phenotypes of colorectal cancer.

BACKGROUND: Methylated SDC2 and TFPI2 are widely used for colorectal cancer (CRC) detection. However, they often miss some CRCs, which directly diminishes the sensitivity. Further investigations of the underlying mechanisms leading to the missed samples will facilitate developing more eligible methylation markers. METHODS: CRC samples from TCGA and GEO datasets were divided into three groups, High-methylation/ High-methylation (HH), High-methylation/Low-methylation (HL), and Low-methylation/Low-methylation (LL) according to the methylation status of SDC2 and TFPI2 promoters. Variations in age, tumor location and microsatellite instable were then assessed between the three groups and verified in our custom cohort. RESULTS: Samples of HL group preferred to derive from left-sided CRCs (P < 0.05). HH samples showed the highest microsatellite instability and mutation load (mean nonsynonymous mutations for HH/HL/LL: 10.55/3.91/7.02, P = 0.0055). Almost all mutations of BRAF, one of the five typical CpG island methylator phenotype (CIMP) related genes, were observed in HH group (HH/HL/LL: 51/0/1, P = 0.018). Besides, older patients were frequently found in HH group. Expression analysis identified 37, 84, and 22 group-specific differentially expressed genes (DEGs) for HH, HL, and LL, respectively. Functional enrichment analysis revealed that HH-specific DEGs were mainly related to transcription regulation, while LL-specific DEGs were enriched in the biological processes of extracellular matrix interaction and cell migration. CONCLUSIONS: The current study revealed that the performance of methylation-based markers might be affected by tumor location, patient age, mutation load and MSI, and these respective sides should be considered when developing new methylation markers for CRC detection.

Antimicrobial and Immunoregulatory Activities of TS40, a Derived Peptide of a TFPI-2 Homologue from Black Rockfish (Sebastes schlegelii).

Tissue factor pathway inhibitor-2 (TFPI-2) is a Kunitz-type serine protease inhibitor. Previous reports have shown that TFPI-2 plays an important role in innate immunity, and the C-terminal region of TFPI-2 proved to be active against a broad-spectrum of microorganisms. In this study, the TFPI-2 homologue (SsTFPI-2) of black rockfish (Sebastods schegelii) was analyzed and characterized, and the biological functions of its C-terminal derived peptide TS40 (FVSRQSCMDVCAKGAKQHTSRGNVRRARRNRKNRITYLQA, corresponding to the amino acid sequence of 187-226) was investigated. The qRT-PCR (quantitative real-time reverse transcription-PCR) analysis showed that the expression of SsTFPI-2 was higher in the spleen and liver. The expression of SsTFPI-2 increased significantly under the stimulation of Listonella anguillarum. TS40 had a strong bactericidal effect on L. anguillarum and Staphylococcus aureus. Further studies found that TS40 can destroy the cell structure and enter the cytoplasm to interact with nucleic acids to exert its antibacterial activity. The in vivo study showed that TS40 treatment could significantly reduce the transmission of L. anguillarum and the viral evasion in fish. Finally, TS40 enhanced the respiratory burst ability, reactive oxygen species production and the expression of immune-related genes in macrophages, as well as promoted the proliferation of peripheral blood leukocytes. These results provide new insights into the role of teleost TFPI-2.

Irisin, an exercise myokine, potently suppresses tumor proliferation, invasion, and growth in glioma.

Glioblastoma multiforme is the most common and aggressive glial tumor with poor prognosis. Importantly, effective treatment options for glioblastoma are unmet needs. Obesity and low physical activity have been linked with a high risk of cancer, and exercise is related to delayed cancer development and progression. Epidemiological studies have revealed a correlation between exercise and the survival rate of patients with glioblastoma. Nevertheless, the mechanisms by which exercise exerts its anticancer effects in glioblastoma remain unclear. Here, we found that irisin, an exercise-induced myokine, induced G2 /M cell cycle arrest and increased p21 levels in glioblastoma cells, leading to the inhibition of cell proliferation. In addition, irisin inhibited glioblastoma cell invasion by upregulating TFPI-2 and even reversed the aggressive tumor phenotype promoted by co-cultivation with cancer-associated adipocytes. Furthermore, irisin retarded xenograft glioblastoma tumor growth, and radiolabeled irisin demonstrated specific tumor-targeting capability in vivo. Therefore, this study identified one potential molecular mechanism by which exercise prevents cancer progression via irisin. Intriguingly, irisin has the potential to be developed as a molecular imaging and therapeutic anticancer agent.

Preparation of FA-targeted magnetic nanocomposites co-loading TFPI-2 plasmid and cis-platinum and its targeted therapy effects on nasopharyngeal carcinoma.

The majority of patients diagnosed with nasopharyngeal carcinoma (NPC) present with advanced-stage disease. The main treatment for these patients is concurrent chemoradiotherapy, which has various side effects. To improve the therapeutic effects and reduce the side effects of NPC chemoradiotherapy, we constructed a multifunctional folic acid (FA)-targeted magnetic nanocomposite codelivering tissue factor pathway inhibitor-2 (TFPI-2) and cisplatin (CDDP). This novel nanocomposite (FA-MNP/CDDP/TFPI-2) was obtained by amidation and electrostatic adsorption between FA-methoxypolyethylene glycol-polyethyleneimine (FA-MPEG-PEI) containing the TFPI-2 plasmid and magnetic nanoparticles modified by aldehyde sodium alginate loaded with CDDP. Transmission electron microscopy (TEM) images showed that the size of the individual magnetite particle core was approximately 11.5 nm. The structure and composition of the nanocomposites were identified and examined by 1H nuclear magnetic resonance (NMR) spectroscopy and ultraviolet (UV) spectrophotometry. The fluorescence analysis, Prussian blue iron staining, magnetic resonance (MR) imaging and whole-body fluorescence imaging results demonstrated that FA-MNP/CDDP/TFPI-2 showed high gene transfection efficiency and could target tumor cells via folate receptor (FR)-mediated delivery. The codelivery analysis showed that the obtained FA-MNP/CDDP/TFPI-2 composite could cause significantly more apoptosis than treatment with CDDP or TFPI-2 alone. The results showed that the FA-MNP/CDDP/TFPI-2 composites were successfully synthesized and indicated to be a specific molecular target for the FR with significant inhibitory effects on the growth of HNE-1 cells.

Validation of tissue factor pathway inhibitor 2 as a specific biomarker for preoperative prediction of clear cell carcinoma of the ovary.

BACKGROUND: Tissue factor pathway inhibitor 2 (TFPI2) is a novel serum biomarker that discriminates ovarian clear cell carcinoma (CCC) from borderline ovarian tumors (BOTs) and non-clear cell epithelial ovarian cancers (EOCs). Here, we examined the performance of TFPI2 for preoperative diagnosis of CCC. METHODS: Serum samples were obtained preoperatively from patients with ovarian masses, who needed surgical treatment at five hospitals in Japan. The diagnostic powers of TFPI2 and cancer antigen 125 (CA125) serum levels to discriminate CCC from BOTs, other EOCs, and benign lesions were compared. RESULTS: A total of 351 patients including 69 CCCs were analyzed. Serum TFPI2 levels were significantly higher in CCC patients (mean ± SD, 508.2 ± 812.0 pg/mL) than in patients with benign lesions (154.7 ± 46.5), BOTs (181 ± 95.5) and other EOCs (265.4 ± 289.1). TFPI2 had a high diagnostic specificity for CCC (79.5%). In patients with benign ovarian endometriosis, no patient was positive for TFPI2, but 71.4% (15/21) were CA125 positive. TFPI2 showed good performance in discriminating stage II-IV CCC from BOTs and other EOCs (AUC 0.815 for TFPI2 versus 0.505 for CA125) or endometriosis (AUC 0.957 for TFPI2 versus 0.748 for CA125). The diagnostic sensitivity of TFPI2 to discriminate CCC from BOTs and other EOCs was improved from 43.5 to 71.0% when combined with CA125. CONCLUSIONS: High specificity of TFPI2 for preoperative detection of CCC was verified with the defined cutoff level of TFPI2 in clinical practice. TFPI2 and CA125 may contribute substantially to precise prediction of intractable CCC.

TFPI-2 inhibits the invasion and metastasis of bladder cancer cells.

INTRODUCTION: Bladder cancer metastasis seriously affects the prognosis of patients, but its molecular mechanism is unclear. This study sought to explore the roles of tissue factor pathway inhibitor-2 (TFPI-2) gene overexpression in the infiltration and metastasis of bladder cancer. MATERIALS: Firstly, real-time PCR and immunohistochemistry were used to compare the mRNA and protein expression levels, respectively, of TFPI-2 and matrix metalloproteinase-1 (MMP-1) in adjacent non-tumoral tissues, muscle-invasive bladder cancer (MIBC) tissues, and non-muscle-invasive bladder cancer (NMIBC) tissues. BIU-87-TFPI-2 cells that stably expressed TFPI-2 were generated by transfection with pcDNA3.1-TFPI-2. Real-time PCR and western blotting were performed to determine the mRNA and protein expression levels, respectively, of TFPI-2 and MMP-1 in BIU-87-TFPI-2 cells. The invasion and migration abilities of BIU-87-TFPI-2 cells were investigated using the Transwell chamber method. RESULTS: TFPI-2 was found to be significantly downregulated in bladder cancer tissue. The expression of MMP-1 was increased with the progression of bladder cancer. BIU-87 cells that overexpressed TFPI-2 were successfully generated by transfection with pcDNA3.1-TFPI-2. TFPI-2 overexpression in BIU-87 cells significantly inhibited cancer cell invasion and metastasis. Furthermore, the mRNA and protein expression levels of MMP-1 were significantly reduced in TFPI-2-overexpressing cells. CONCLUSION: Decreased TFPI-2 expression in bladder tissue was correlated with invasion and metastasis in bladder cancer. TFPI-2 overexpression could inhibit bladder cancer cell invasion and migration in vitro by inhibiting MMP-1 protein expression. LEVEL OF PROOF: 3.

TFPI2 suppresses breast cancer progression through inhibiting TWIST-integrin α5 pathway.

BACKGROUND: Tissue factor pathway inhibitor 2 (TFPI2) participates in carcinogenesis of various tumors, and is associated with poor survival of breast cancer patients. However, the effect and underlying mechanism of TFPI2 on breast cancer progression remains to be investigated. METHODS: The expression level of TFPI2 in breast cancer tissues and cell lines was examined via qRT-PCR (quantitative real-time polymerase chain reaction) and immunohistochemistry. CCK8 (Cell Counting Kit-8), colony formation, wound healing or transwell assays were used to detect cell viability, proliferation, migration or invasion, respectively. In vivo subcutaneous xenotransplanted tumor model was established to detect tumorigenic function of TFPI2, and the underlying mechanism was evaluated by immunohistochemistry and western blot. RESULTS: TFPI2 was down-regulated in breast cancer tissues and cell lines, and was associated with poor prognosis of patients diagnosed with breast cancer. Over-expression of TFPI2 inhibited cell viability, proliferation, migration and invasion of breast cancer cells. Mechanistically, Twist-related protein 1 (TWIST1) was negatively associated with TFPI2 in breast cancer patients, whose expression was decreased by TFPI2 over-expression or increased by TFPI2 knockdown. Moreover, TWIST1 could up-regulate integrin α5 expression. Functional assays indicated that the inhibition abilities of TFPI2 over-expression on breast cancer progression were reversed by TWIST1 over-expression. In vivo subcutaneous xenotransplanted tumor model also revealed that over-expression of TFPI2 could suppress breast tumor growth via down-regulation of TWIST1-mediated integrin α5 expression. CONCLUSIONS: TFPI2 suppressed breast cancer progression through inhibiting TWIST-integrin α5 pathway, providing a new potential therapeutic target for breast cancer treatment.

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.

TFPI2 and NDRG4 gene promoter methylation analysis in peripheral blood mononuclear cells are novel epigenetic noninvasive biomarkers for colorectal cancer diagnosis.

BACKGROUND: As a result of the growing prevalence of colorectal cancer (CRC), new screening and early detection methods are required. Among the novel biomarkers, DNA methylation has emerged as a high-potential diagnosis/screening molecular marker. The present study aimed to assess non-invasive early diagnosis of CRC by examining promoter methylation of TFPI2 and NDRG4 genes in peripheral blood mononuclear cells (PBMCs). METHODS: Fifty CRC patients and 50 normal controls were recruited to the present study. Quantitative methylation of the promoter region of the TFPI2 and NDRG4 genes was analyzed in DNA extracted from PBMCs of all cases and control subjects using a methylation-quantification endonuclease-resistant DNA (MethyQESD) method. RESULTS: The sensitivity and specificity of the TFPI2 gene for the diagnosis of CRC was 88% and 92%, respectively, and, for the NDRG4 gene, it was 86% and 92%, respectively. The methylation range for the TFPI2 gene was 43.93% and 11.56% in patients and controls, respectively, and, for the NDRG4 gene, it was 38.8% in CRC patients and 12.23% in healthy controls (p < 0.001). In addition, we observed that a higher percentage of methylation was correlated with the higher stage of CRC. CONCLUSIONS: The results of the present study reveal that PBMCs are reliable sources of methylation analysis for CRC screening. Furthermore, the TFPI2 and NDRG4 genes provide sufficiently high sensitivity and specificity to be nominated for use in a novel noninvasive CRC screening method in PBMCs.

Methylation-mediated silencing of the LIM homeobox 6 (LHX6) gene promotes cell proliferation in human pancreatic cancer.

Epigenetic gene silencing by aberrant DNA methylation leads to loss of key cellular pathways in tumorigenesis. DNA methylation-mediated silenced genes in pancreatic cancer were searched for using the methyl-CpG targeted transcriptional activation (MeTA) method, and LHX6 (LIM homeobox 6), a transcription factor involved in embryogenesis and head development, was selected as a strong candidate gene. LHX6 was downregulated in most of the pancreatic cancer cell lines (83%, 10/12), mainly through promoter hypermethylation and histone deacetylation. Furthermore, LHX6 was methylated in primary pancreatic cancer specimens (57%, 16/28) in a tumor-specific manner. Re-expression of LHX6 inhibited colony formation and proliferation in LHX6 low-expressing pancreatic cancer cell lines, PK-1 and PK-9. In contrast, knockdown of LHX6 accelerated cell proliferation in LHX6 high-expressing pancreatic cancer cell lines, PCI-35 and MIA PaCa-2. In order to analyze LHX6 downstream genes, we performed microarray analyses using LHX6 inducible PK-1 and PK-9 and found that LHX6 induction upregulated several genes that had tumor suppressive functions. Among these, we focused on TFPI2 (Tissue factor pathway inhibitor-2) and found that TFPI2 was greatly downregulated in all twelve pancreatic cancer cell lines. Our present results suggest that epigenetic inactivation of LHX6 plays an important role in pancreatic tumorigenesis by promoting cell proliferation through aberrant transcriptional regulation of several cancer-related genes.

Heparanase in the Coagulation System.

The hemostatic cascade is initiated by the transmembrane coagulation protein - tissue factor (TF) and eventuates in fibrin formation. Heparanase protein was demonstrated to directly enhance TF activity resulting in increased activation of the coagulation system. In addition, heparanase was found to increase hemostatic system activation via two other mechanisms: up-regulating TF expression in endothelial cells and releasing the protein tissue factor pathway inhibitor (TFPI) from the cell surface. Peptides derived from TFPI-2, a protein similar to TFPI, were shown to inhibit the TF/heparanase complex as well as attenuate sepsis and tumor growth. Increased heparanase procoagulant activity was observed in several clinical settings, including women using oral contraceptives, women at delivery, patients following orthopedic surgery and patients with diabetic foot, shift work female nurses, patients with lung cancer, retinal vein thrombosis and prosthetic heart valve thrombosis. Remarkably, the heparanase profile was significantly different across the tested groups. Inhibition of TF / heparanase interaction may represent a new target for attenuating coagulation, cancer and inflammation.

Vitexin ameliorates preeclampsia phenotypes by inhibiting TFPI-2 and HIF-1α/VEGF in a l-NAME induced rat model.

Preeclampsia (PE) is a leading cause of maternal and perinatal morbidity and mortality with few safe, effective, and minimally invasive therapeutics. Inflammation, oxidative stress, and angiogenic imbalance have been reported to contribute to PE pathogenesis. Vitexin (VI) possesses various pharmacological activities including the potent regulation of the above biological processes in different conditions. This study aims to investigate whether VI has therapeutic potential to PE and the underlying mechanisms. Sprague-Dawley pregnant rats pretreated with or without VI were fed with l-NAME-containing water to induce experimental PE. Results showed that VI decreased high systolic blood pressure and urinary protein in PE rats time- and dose-dependently. Meanwhile, VI of higher dosage (45, 60 mg/kg) corrected abnormal pregnancy outcomes, including low pup weight and low pups/placenta ratio. In addition, VI of high dosage (60 mg/kg) decreased sFlt-1, increased PlGF and alleviated oxidative stress both in blood and placental samples compared with nontreated PE group. Furthermore, VI alleviated placental TFPI-2, HIF 1α, and VEGF in PE rats. In short, the present study suggests that the inhibition of placental TFPI-2 and HIF-1α/VEGF might be one of the potential mechanisms underlying the protective effects of VI to experimental PE induced by l-NAME.

A teleost TFPI-2 peptide that possesses a broad antibacterial spectrum and immune-stimulatory properties.

Tissue factor pathway inhibitor 2 (TFPI-2) is an analogue of TFPI-1 and a potent endogenous inhibitor of tissue factor (TF)-mediated blood coagulation. Previous reports have shown that several peptides derived from human and vertebrates TFPI-2 possess antibacterial activity against diverse bacteria. In this study, a C-terminal peptide, TO24 (with 24 amino acids), derived from red drum (Sciaenops ocellatus) TFPI-2, was synthesized and investigated for its antimicrobial spectrum, action mode, as well as the immune-stimulatory property. Our results indicated that TO24 was active against Gram-positive bacteria Micrococcus luteus and Staphylococcus aureus; Gram-negative bacteria Vibrio litoralis, Vibrio ichthyoenteri, Vibrio vulnificus and Vibrio scophthalmi, as well as fish megalocytivirus, infectious spleen and kidney necrosis virus (ISKNV). During its interaction with V. vulnificus, TO24 exerted its antibacterial activity by destroying cell membrane integrity, penetrating the cytoplasm and inducing degradation of genomic DNA and total RNA. In addition, TO24 had no hemolytic activity against red drum blood cells. In vitro, TO24 enhanced bactericidal activity of red drum macrophages. In vivo, administration of red drum with TO24 before bacterial infection significantly reduced pathogen dissemination and replication in tissues. These results indicate that TO24 is a broad-spectrum antimicrobial peptide with immune-stimulatory properties and it has the potential to be used as an antimicrobial agent in aquaculture.