Anti-tissue factor short hairpin RNA inhibits breast cancer growth in vivo

Fibrinogen and D-dimer levels elevate in advanced hepatocellular carcinoma: High pretreatment fibrinogen levels predict poor outcomes

AIM

Plasma fibrinogen and D-dimer have been reported to predict survival in several types of malignancies. The aim of this study is to investigate their predictive value in patients with hepatocellular carcinoma (HCC).

METHODS

We retrospectively analyzed plasma fibrinogen and D-dimer levels from 252 subjects: control (n = 20), hepatitis (n = 20), cirrhosis (n = 20), and HCC (n = 192) subjects. The clinical involvement and prognostic value of fibrinogen and D-dimer was analyzed in HCC subjects. To confirm the effects of tumor on hypercoagulability and fibrinolysis, fibrinogen and D-dimer levels were measured in nude mice following HCC inoculation.

RESULTS

Fibrinogen decreased and D-dimer increased in cirrhosis subjects relative to other groups. In HCC subjects, elevated fibrinogen and D-dimer levels were significantly associated with adverse tumor features (increased size, stage, and grade) and systemic inflammation. Patients with HCC with either elevated fibrinogen or D-dimer levels had significantly higher 3-year tumor recurrence rates (65% vs. 41%, P < 0.001 for fibrinogen; 67% vs. 40%, P = 0.011 for D-dimer) and significantly lower 3-year overall survival rates (57% vs. 79%, P < 0.001 for fibrinogen; 56% vs. 80%, P = 0.001 for D-dimer). After multivariate analysis, elevated fibrinogen levels remained an independent predictor of poor prognosis in HCC patients. Finally, elevated levels of fibrinogen and D-dimer were confirmed in nude mice following tumor inoculation.

CONCLUSION

The fibrinogen and D-dimer levels, elevating after carcinogenesis, may serve as simple but effective predictors of adverse tumor profiles and outcomes in HCC.

Alternatively spliced tissue factor promotes breast cancer growth in a β1 integrin-dependent manner

Full-length tissue factor (flTF), the coagulation initiator, is overexpressed in breast cancer (BrCa), but associations between flTF expression and clinical outcome remain controversial. It is currently not known whether the soluble alternatively spliced TF form (asTF) is expressed in BrCa or impacts BrCa progression. We are unique in reporting that asTF, but not flTF, strongly associates with both tumor size and grade, and induces BrCa cell proliferation by binding to β1 integrins. asTF promotes oncogenic gene expression, anchorage-independent growth, and strongly up-regulates tumor expansion in a luminal BrCa model. In basal BrCa cells that constitutively express both TF isoforms, asTF blockade reduces tumor growth and proliferation in vivo. We propose that asTF plays a major role in BrCa progression acting as an autocrine factor that promotes tumor progression. Targeting asTF may comprise a previously unexplored therapeutic strategy in BrCa that stems tumor growth, yet does not impair normal hemostasis.

Effect of HMGA2 gene silencing on Wnt/β-Catenin signaling pathway in gastric cancer cells

AIM: To induce HMGA2 gene silencing with shRNAs in gastric cancer cell line MKN-45 and to study the interaction between HMGA2 and the Wnt/β-Catenin signaling pathway.

METHODS: A shRNA eukaryotic expression vector that expresses shRNAs of HMGA2 was constructed and transfected into gastric cancer cell line MKN-45. The mRNA and protein expression of HMGA2 was measured by RT-PCR and Western blot 48 h and 72 h after transfection to evaluate the effect of RNA interference. The mRNA and protein expression of β-Catenin, c-myc and cyclin D1 were also measured by RT-PCR and Western blot.

RESULTS: The expression of HMGA2 mRNA 48 h after transfection was significantly lower in the shHMG-A2-1 group than in the shHMGA2-2 group, shHMGA2-3 group, scrambled group and blank control group (0.58 ± 0.07 vs 0.92 ± 0.13, 0.90 ± 0.16, 1.07 ± 0.14, 1.19 ± 0.09, all P < 0.05), but showed no significant difference among the latter four groups (all P > 0.05). Since HMGA2 expression was most significantly silenced in the shHMGA2-1 group (51.3% at 48 h), the plasmid pLLU2G-shHMGA2-1 was chosen for use in subsequent experiments. The expression of HMGA2 protein 72 h after transfection in the shHMGA2-1 group was significantly lower than that in the scrambled group and blank group (0.11 ± 0.03 vs 0.48 ± 0.12, 0.55 ± 0.08, both P < 0.05). The silencing efficiency of transfection of shHMGA2-1 was 80% at 72 h. After silencing the HMGA2 gene, the expression of β-Catenin, c-myc and cyclin D1 mRNAs and proteins was significantly inhibited in the shHMGA2-1 group compared to the blank control group and the scrambled group (β-Catenin mRNA: 0.53 ± 0.04 vs 1.07 ± 0.02, 0.91 ± 0.02; β-Catenin protein: 0.44 ± 0.05 vs 0.69 ± 0.04, 0.67 ± 0.10; c-myc mRNA: 0.39 ± 0.04 vs 0.88 ± 0.05, 0.84 ± 0.03; c-myc protein: 0.25 ± 0.07 vs 0.75 ± 0.09, 0.66 ± 0.10; cyclin D1 mRNA: 0.31 ± 0.02 vs 0.52 ± 0.03, 0.51 ± 0.01; cyclin D1 protein: 0.12 ± 0.01 vs 0.73 ± 0.12, 0.61 ± 0.07; all P < 0.05).

CONCLUSION: The recombinant plasmid PLLU2G-shHMGA2 could effectively inhibit the expression of HMGA2 gene in gastric cancer cell line MKN-45. Silencing of the HMGA2 gene restrained the expression of β-Catenin and its downstream target genes c-myc and cyclin D1. HMGA2 controls the growth and apoptosis of gastric cancer cells possibly via the Wnt/β-Catenin signal pathway.

EGFP-EGF1-conjugated PLGA nanoparticles for targeted delivery of siRNA into injured brain microvascular endothelial cells for efficient RNA interference

Injured endothelium is an important target for drug and/or gene therapy because brain microvascular endothelial cells (BMECs) play critical roles in various pathophysiological conditions. RNA-mediated gene silencing presents a new therapeutic approach for treating such diseases, but major challenge is to ensure minimal toxicity and target delivery of siRNA to injured BMECs. Injured BMECs overexpress tissue factor (TF), which the fusion protein EGFP-EGF1 could be targeted to. In this study, TNF alpha (TNF-α) was chosen as a stimulus for primary BMECs to produce injured endothelium in vitro. The EGFP-EGF1-PLGA nanoparticles (ENPs) with loaded TF-siRNA were used as a new carrier for targeted delivery to the injured BMECs. The nanoparticles then produced intracellular RNA interference against TF. We compared ENP-based transfections with NP-mediated transfections, and our studies show that the ENP-based transfections result in a more efficient downregulation of TF. Our findings also show that the TF siRNA-loaded ENPs had minimal toxicity, with almost 96% of the cells viable 24 h after transfection while Lipofectamine-based transfections resulted in only 75% of the cells. Therefore, ENP-based transfection could be used for efficient siRNA transfection to injured BMECs and for efficient RNA interference (RNAi). This transfection could serve as a potential treatment for diseases, such as stroke, atherosclerosis and cancer.

ShRNA-mediated HMGA2 gene silencing inhibits cell proliferation and promotes apoptosis in human gastric cancer cell line MKN-45

AIM: To investigate the effect of short hairpin RNA (shRNA)-mediated HMGA2 gene silencing on cell growth and apoptosis in human gastric cancer cell line MKN-45.

METHODS: A shRNA eukaryotic expression vector that expresses shRNA targeting the HMGA2 gene was constructed and transfected into MKN-45 cells. HMGA2 protein expression was measured by immunocytochemistry 72 hours after transfection. Cell growth and apoptosis were determined by MTT assay and flow cytometry, respectively.

RESULTS: Compared to the scrambled siRNA group and blank control group, the expression of HMGA2 protein was significantly decreased (171.34 ± 19.61 vs 143.48 ± 19.04, 141.79 ± 18.09, both P < 0.05); cell growth was significantly inhibited (39.32% ± 2.37% vs 5.66% ± 0.63%, P< 0.05); and cell apoptosis was significantly enhanced in the HMGA2-shRNA group (39.67% ± 2.35% vs 4.29% ± 1.33%, 5.05% ± 1.84%, both P < 0.05).

CONCLUSION: ShRNA-mediated HMGA2 gene silencing can effectively induce growth inhibition and apoptosis of MKN-45 cells. HMGA2 might be a potential target for the therapy of gastric cancer.

Tissue Factor Regulates Microvessel Formation and Stabilization by Induction of Chemokine (C-C motif) Ligand 2 Expression

Objective—

Tissue factor (TF) triggers arterial thrombosis. TF is also able to initiate cellular signaling mechanisms leading to angiogenesis. Because high cardiovascular risk atherosclerotic plaques show significant angiogenesis, our objective was to investigate whether TF is able to trigger and stabilize atherosclerotic plaque neovessel formation.

Methods and Results—

In this study, we showed, by real-time confocal microscopy in 3-dimensional basement membrane cocultures, that TF in human microvascular endothelial cells (HMEC-1) and in human vascular smooth muscle cells (HVSMCs) plays an important role in the formation of capillary-like networks. TF silencing in endothelial cells and smooth muscle cells inhibits the formation of tube-like structures with stable phenotype. Using an in vivo model, we observed that TF inhibition in either HMEC-1 or HVSMCs reduced their shared ability to form new capillaries. The phenotypic changes induced by TF silencing were linked to reduced chemokine (C-C motif) ligand 2 (CCL2) expression in endothelial cells. Wound healing and chemotactic assays demonstrated that TF-induced release of CCL2 stimulated HVSMC migration to HMEC-1.

Conclusion—

Endogenous TF regulates CCL2 production in endothelial cells. Secreted CCL2 mediates the angiogenic effect of TF by recruiting smooth muscle cells toward endothelial cells and facilitates the maturation of newly formed microvessels.

Combined RNA interference of hexokinase II and (131)I-sodium iodide symporter gene therapy for anaplastic thyroid carcinoma

The purpose of this study was to investigate the enhanced therapeutic effect of the combined use of shRNA (small hairpin RNA) therapy for the hexokinase II (HKII) gene and (131)I human sodium iodide symporter (hNIS) as a gene therapy for in vitro and in vivo treatment of anaplastic thyroid carcinoma cells (ARO) in an animal model.

METHODS

A recombinant lentivirus containing a plasmid with the hNIS gene driven by phosphoglycerate kinase promoter and green fluorescent protein (GFP) linked with an internal ribosome entry site sequence was produced. ARO cells were transfected with the virus and sorted by fluorescent activated cell sorting using GFP (ARO-NG). The messenger RNA expression of hNIS and GFP were evaluated with reverse-transcriptase polymerase chain reaction, and the function of hNIS was verified by (125)I uptake. The lentiviral vector expressing shRNA against HKII (Lenti-HKII shRNA) was constructed and used to infect ARO-NG cells. The effect of Lenti-HKII shRNA was evaluated by reverse-transcriptase polymerase chain reaction, (18)F-FDG uptake, and HK activity. An in vitro clonogenic assay was performed after Lenti-HKII shRNA therapy, (131)I therapy, and a combined therapy. The therapies were also applied in vivo to an animal model with an ARO-NG xenograft, and the effects were assessed with caliper measurements and (18)F-FDG PET.

RESULTS

ARO-NG cells showed an (125)I uptake 76-fold higher than the parent ARO cells. Compared with the uninfected ARO-NG cells, ARO-NG cells infected with Lenti-HKII shRNA had lower HKII messenger RNA expression, lower (18)F-FDG uptake, and HK activity. The proliferation of ARO-NG cells was inhibited by (131)I and Lenti-HKII shRNA therapies and further inhibited by the combined (131)I and Lenti-HKII shRNA therapy. Both the Lenti-HKII shRNA therapy and the (131)I therapy inhibited in vivo tumor growth in the tumor xenograft model. The combined Lenti-HKII shRNA and (131)I therapy resulted in a further decrease of tumor growth.

CONCLUSION

Our results suggest that the combined HKII shRNA and (131)I therapy has a stronger antitumor effect than either the (131)I therapy or the HKII shRNA alone. Therefore, this combined therapy could be used as a powerful strategy for treating anaplastic thyroid carcinoma.

Tissue factor, blood coagulation, and beyond: an overview

Emerging evidence shows a broad spectrum of biological functions of tissue factor (TF). TF classical role in initiating the extrinsic blood coagulation and its direct thrombotic action in close relation to cardiovascular risks have long been established. TF overexpression/hypercoagulability often observed in many clinical conditions certainly expands its role in proinflammation, diabetes, obesity, cardiovascular diseases, angiogenesis, tumor metastasis, wound repairs, embryonic development, cell adhesion/migration, innate immunity, infection, pregnancy loss, and many others. This paper broadly covers seminal observations to discuss TF pathogenic roles in relation to diverse disease development or manifestation. Biochemically, extracellular TF signaling interfaced through protease-activated receptors (PARs) elicits cellular activation and inflammatory responses. TF diverse biological roles are associated with either coagulation-dependent or noncoagulation-mediated actions. Apparently, TF hypercoagulability refuels a coagulation-inflammation-thrombosis circuit in “autocrine” or “paracrine” fashions, which triggers a wide spectrum of pathophysiology. Accordingly, TF suppression, anticoagulation, PAR blockade, or general anti-inflammation offers an array of therapeutical benefits for easing diverse pathological conditions.