Novel strategy of ovarian cancer implantation: Pre-invasive growth of fibrin-anchored cells with neovascularization

Tissue factor-induced fibrinogenesis mediates cancer cell clustering and multiclonal peritoneal metastasis

Peritoneal metastasis is one of the most frequent causes of death in several types of advanced cancers; however, the underlying molecular mechanisms remain largely unknown. In this study, we exploited multicolor fluorescent lineage tracking to investigate the clonality of peritoneal metastasis in mouse xenograft models. When peritoneal metastasis was induced by intraperitoneal or orthotopic injection of multicolored cancer cells, each peritoneally metastasized tumor displayed multicolor fluorescence regardless of metastasis sites, indicating that it consists of multiclonal cancer cell populations. Multicolored cancer cell clusters form within the peritoneal cavity and collectively attach to the peritoneum. In vitro, peritoneal lavage fluid or cleared ascitic fluid derived from cancer patients induces cancer cell clustering, which is inhibited by anticoagulants. Cancer cell clusters formed in vitro and in vivo are associated with fibrin formation. Furthermore, tissue factor knockout in cancer cells abrogates cell clustering, peritoneal attachment, and peritoneal metastasis. Thus, we propose that cancer cells activate the coagulation cascade via tissue factor to form fibrin-mediated cell clusters and promote peritoneal attachment; these factors lead to the development of multiclonal peritoneal metastasis and may be therapeutic targets.

Peritoneal dissemination of high-grade serous ovarian cancer: pivotal roles of chromosomal instability and epigenetic dynamics

Epithelial ovarian cancer remains the lethal gynecological malignancy in women. The representative histotype is high-grade serous carcinoma (HGSC), and most patients with HGSC present at advanced stages with peritoneal dissemination. Since the peritoneal dissemination is the most important factor for poor prognosis of the patients, complete exploration for its molecular mechanisms is mandatory. In this narrative review, being based on the clinical, pathologic, and genomic findings of HGSC, chromosomal instability and epigenetic dynamics have been discussed as the potential drivers for cancer development in the fallopian tube, acquisition of cancer stem cell (CSC)-like properties, and peritoneal metastasis of HGSC. The natural history of carcinogenesis with clonal evolution, and adaptation to microenvironment of peritoneal dissemination of HGSC should be targeted in the novel development of strategies for prevention, early detection, and precision treatment for patients with HGSC.

Rosa hybrida Petal Extract Exhibits Antitumor Effects by Abrogating Tumor Progression and Angiogenesis in Bladder Cancer Both In Vivo and In Vitro

The edible Rosa hybrida (RH) petal is utilized in functional foods and cosmetics. Although the biological function of RH petal extract is known, mechanism of action studies involving tumor-associated angiogenesis have not yet been reported. Herein, we investigated the regulatory effect of the ethanol extract of RH petal (EERH) on tumor growth and tumor angiogenesis against bladder cancer. EERH treatment inhibited the bladder carcinoma T24 cell and 5637 cell proliferation because of G₁-phase cell cycle arrest by inducing p21WAF1 expression and reducing cyclins/CDKs level. EERH regulated signaling pathways differently in both cells. EERH-stimulated suppression of T24 and 5637 cell migration and invasion was associated with the decline in transcription factor-mediated MMP-9 expression. EERH oral administration to xenograft mice reduced tumor growth. Furthermore, no obvious toxicity was observed in acute toxicity test. Decreased CD31 levels in EERH-treated tumor tissues led to examine the angiogenic response. EERH alleviated VEGF-stimulated tube formation and proliferation by downregulating the VEGFR2/eNOS/AKT/ERK1/2 cascade in HUVECs. EERH impeded migration and invasion of VEGF-induced HUVECs, which is attributed to the repressed MMP-2 expression. Suppression of neo-microvessel sprouting, induced by VEGF, was verified by treatment with EERH using the ex vivo aortic ring assay. Finally, kaempferol was identified as the main active compound of EERH. The present study demonstrated that EERH may aid the development of antitumor agents against bladder cancer.

The anti-ovarian cancer effect of RPV modified paclitaxel plus schisandra B liposomes in SK-OV-3 cells and tumor-bearing mice

AIMS

Due to poor targeting ability of anti-tumor drugs and self-adaptation of tumors, the chemotherapy of ovarian cancer is still poorly effective. In recent years, the treatment of tumor with nano-targeted agents has become a potential research focus. In this study, a new type of short cell-penetrating peptide RPV-modified paclitaxel plus schisandrin B liposomes were constructed to disrupt VM channels, angiogenesis, proliferation and migration for the treatment of ovarian cancer.

MATERIALS AND METHODS

In this study, clone assay, TUNEL, Transwell, wound-healing, CAM and mimics assay were used to detect the effects of RPV-modified liposomes on ovarian cancer SK-OV-3 cells before and after treatment. HE-staining, immunofluorescence and ELISA were used to further detect the expression of tumor-related proteins.

KEY FINDINGS

RPV-modified paclitaxel plus schisandrin B liposomes can inhibit angiogenesis, VM channel formation, invasion and proliferation of ovarian SK-OV-3 cells. In vitro and in vivo studies showed that tumor-related protein expression was down-regulated. Modification of RPV can prolong the retention time of liposome in vivo and accumulate in the tumor site, increasing the anti-tumor efficacy.

SIGNIFICANCE

The RPV-modified paclitaxel plus schisandrin B liposomes have good anti-tumor effect, thus may provide a new avenue for the treatment of ovarian cancer.

The Detection of Plasma Soluble Podoplanin of Patients with Breast Cancer and Its Clinical Signification

Background

Podoplanin (PDPN) is a type-1 membrane sialoglycoprotein that is expressed in many cancer tumors including breast cancer; nonetheless, its roles in tumor occurrence, development, and metastasis are unclear. In this study, we aimed to investigate the clinical significance of plasma soluble PDPN (sPDPN) levels in patients with breast cancer and its significance in the diagnosis and metastasis.

Materials and Methods

Blood samples from healthy controls (CTL), patients with fibroadenomas of breast (FOB), and breast cancer (pathological type: invasive ductal carcinoma, IDC) were collected. sPDPN levels in the plasma of CTL and patients with FOB and IDC were measured by the ELISA.

Results

The plasma sPDPN levels in IDC patients (159 cases, 22.59±3.70 ng/mL) were higher than those in FOB patients (50 cases, 8.29±1.09 ng/mL; P<0.05) and CTL (100 cases, 1.21±0.12 ng/mL; P<0.0001). The sPDPN levels in patients at stage III and stage IV (30.08±4.66 ng/mL) were higher than in patients at stage I and stage II (11.84±1.12 ng/mL; P=0.005). The sPDPN levels in patients with high-moderate and moderate differentiation (17.50±3.02 ng/mL) were lower than those in patients with moderately low and low differentiation (35.73±4.26 ng/mL; P=0.026). The sPDPN levels in patients with metastasis (30.60±4.27 ng/mL) were much higher than those in patients without metastasis (13.02±1.30 ng/mL; P=0.017).

Conclusion

Plasma sPDPN may be used as a new marker for the determination of the clinical stage, differentiation degree, and metastasis status of breast cancer.

Piceatannol, a Natural Analog of Resveratrol, Exerts Anti-angiogenic Efficiencies by Blockage of Vascular Endothelial Growth Factor Binding to Its Receptor

Piceatannol is also named as trans-3,4,3′,5′-tetrahydroxy-stilbene, which is a natural analog of resveratrol and a polyphenol existing in red wine, grape and sugar cane. Piceatannol has been proved to possess activities of immunomodulatory, anti-inflammatory, antiproliferative and anticancer. However, the effect of piceatannol on VEGF-mediated angiogenesis is not known. Here, the inhibitory effects of piceatannol on VEGF-induced angiogenesis were tested both in vitro and in vivo models of angiogenesis. In human umbilical vein endothelial cells (HUVECs), piceatannol markedly reduced the VEGF-induced cell proliferation, migration, invasion, as well as tube formation without affecting cell viability. Furthermore, piceatannol significantly inhibited the formation of subintestinal vessel in zebrafish embryos in vivo. In addition, we identified the underlying mechanism of piceatannol in triggering the anti-angiogenic functions. Piceatannol was proposed to bind with VEGF, thus attenuating VEGF in activating VEGF receptor and blocking VEGF-mediated downstream signaling, including expressions of phosphorylated eNOS, Erk and Akt. Furthermore, piceatannol visibly suppressed ROS formation, as triggered by VEGF. Moreover, we further determined the outcome of piceatannol binding to VEGF in cancer cells: piceatannol significantly suppressed VEGF-induced colon cancer proliferation and migration. Thus, these lines of evidence supported the conclusion that piceatannol could down regulate the VEGF-mediated angiogenic functions with no cytotoxicity via decreasing the amount of VEGF binding to its receptors, thus affecting the related downstream signaling. Piceatannol may be developed into therapeutic agents or health products to reduce the high incidence of angiogenesis-related diseases.

Novel strategy of ovarian cancer implantation: Pre-invasive growth of fibrin-anchored cells with neovascularization

Although direct adhesion of cancer cells to the mesothelial cell layer is considered to be a key step for peritoneal invasion of ovarian cancer cell masses (OCM), we recently identified a different strategy for the peritoneal invasion of OCM. In 6 out of 20 cases of ovarian carcinoma, extraperitoneal growth of the OCM was observed along with the neovascularization of feeding vessels, which connect the intraperitoneal host stroma and extraperitoneal lesions through the intact mesothelial cell layer. As an early step, the OCMs anchor in the extraperitoneal fibrin networks and then induce the migration of CD34-positive and vascular endothelial growth factor A (VEGF-A)-positive endothelial cells, constructing extraperitoneal vascular networks around the OCM. During the extraperitoneal growth of OCM, podoplanin-positive and α smooth muscle actin (αSMA)-positive cancer-associated fibroblasts (CAF) appears. In more advanced lesions, the boundary line of mesothelial cells disappears around the insertion areas of feeding vessels and then extraperitoneal and intraperitoneal stroma are integrated, enabling the OCM to invade the host stroma, being associated with CAF. In addition, tissue factors (TF) are strongly detected around these peritoneal implantation sites and their levels in ascites were higher than that in blood. These findings demonstrate the presence of neovascularization around fibrin net-anchored OCMs on the outer side of the intact peritoneal surface, suggesting a novel strategy for peritoneal invasion of ovarian cancer and TF-targeted intraperitoneal anti-cancer treatment. We observed and propose a novel strategy for peritoneal implantation of ovarian cancer. The strategy includes the preinvasive growth of fibrin-anchored cancer cells along with neovascularization on the outer side of the intact peritoneal surface.