Inhibits Tumor Cell Invasion Research Articles

The Identification of Small Molecule Inhibitors That Reduce Invasion and Metastasis of Aggressive Cancers.

Transformed epithelial cells can activate programs of epithelial plasticity and switch from a sessile, epithelial phenotype to a motile, mesenchymal phenotype. This process is linked to the acquisition of an invasive phenotype and the formation of distant metastases. The development of compounds that block the acquisition of an invasive phenotype or revert the invasive mesenchymal phenotype into a more differentiated epithelial phenotype represent a promising anticancer strategy. In a high-throughput assay based on E-cadherin (re)induction and the inhibition of tumor cell invasion, 44,475 low molecular weight (LMW) compounds were screened. The screening resulted in the identification of candidate compounds from the PROAM02 class. Selected LMW compounds activated E-cadherin promoter activity and inhibited cancer cell invasion in multiple metastatic human cancer cell lines. The intraperitoneal administration of selected LMW compounds reduced the tumor burden in human prostate and breast cancer in vivo mouse models. Moreover, selected LMW compounds decreased the intra-bone growth of xenografted human prostate cancer cells. This study describes the identification of the PROAM02 class of small molecules that can be exploited to reduce cancer cell invasion and metastases. Further clinical evaluation of selected candidate inhibitors is warranted to address their safety, bioavailability and antitumor efficacy in the management of patients with aggressive cancers.

Inhibitor of apoptosis protein Livin promotes tumor progression and chemoradioresistance in human anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is characterized by a rapid and aggressive course of progression. Despite significant advances in surgery, radiotherapy and chemotherapy, the disease‑specific mortality due to ATC is approximately100%. New strategies, such as molecular targeted therapies, are imperative for improving survival. Livin, a member of the human inhibitor of apoptosis protein family, has been found to be associated with tumor progression and poor prognosis in various human cancers. The aim of the present study was to evaluate the role of Livin in cancer progression and chemoradioresistance of ATC and to investigate its potential as a therapeutic target. Endogenous Livin expression in the human BHT101 ATC cell line was silenced by Livin‑specific small interfering RNA. To assess the impact of Livin on cancer cell behavior in human ATC cells, various methods such as cell invasion, cell viability and cell apoptosis assays were applied. To assess the expression of Livin and the change of apoptosis‑related proteins associated with Livin expression, reverse transcription‑quantitative PCR and western blotting were performed. Immunohistochemistry was performed to detect Livin protein expression in human ATC tissues. The association between Livin expression and apoptotic/proliferation index was analyzed in human ATC cells. Livin‑knockdown suppressed tumor cell invasion; and conversely, it enhanced cell apoptosis, with elevated expression levels of cleaved caspase‑3 and ‑7 and cleaved PARP. Livin‑knockdown enhanced radiation‑induced apoptosis, while reducing cell viability following radiotherapy, as well as lenvatinib treatment. In addition, human ATC tissues with high Livin‑expression exhibited a high Ki‑67 labeling index and low apoptotic index. In summary, these findings indicate the contribution of Livin to tumor progression and chemoradioresistance in ATC.

Polyamino acid calcified nanohybrids induce immunogenic cell death for augmented chemotherapy and chemo-photodynamic synergistic therapy.

Background: Monotherapy for cancer treatment is limited by unstable efficacy and uncontrollable toxic side effects, while the multifunctional nanoplatform with complex preparation process cannot avoid the potential toxicity of each functional component.Methods: We exploited tumor-specific activated polyamino acid calcified nanoparticles (CHC NPs) as new-type oxidative stress amplification of anticancer drugs via building a safe and biodegradable multifunctional nanoplatform. Giving priority to chemotherapy, and synergizing chemodynamic therapy (CDT) with photodynamic therapy (PDT), this strategy was to achieve enhanced chemotherapy, simultaneously inducing immunogenic cell death and inhibiting tumor cell invasion.Results: Based on amorphous calcium carbonate, pH-responsive nanocarrier was prepared with classical chemotherapeutic drug 10-hydroxycamplothecin (HCPT) and photosensitizer Chlorin e6 (Ce6) to realize multifunctional nanotheranostics.Conclusion: Inventive calcified nanohybrids, where topoisomerase inhibited by HCPT to prevent DNA synthesis, the generation of •OH induced via Fenton reaction, along with a large amount of 1O2 produced by Ce6, might be a promising strategy for anti-tumor combination therapy in clinical translation.

Abstract 5323: Chemical inhibitors of quiescin sulfhydryl oxidase (QSOX1) suppress tumor invasion and metastasis

Abstract Purpose: Quiescin Sulfhydryl Oxidase 1 (QSOX1) is an enzyme over-expressed by tumor cells. Our group and others have shown that QSOX1 is involved in invasion and metastasis. We previously reported that a small molecule, SBI-183, inhibited the enzymatic activity of QSOX1 and suppressed tumor cell invasion in vitro and metastasis of MDA-MB-231 breast tumor cells in vivo. In our current work we tested SPX-009, an analog of SBI-183 with increased potency, to suppress invasion and metastasis in vitro and in vivo. Methods: Commercially available analogs for SBI-183 were screened in a cell-free fluorescent screening assay for the ability to inhibit QSOX1. Analog compounds that inhibited QSOX1 in a concentration-dependent manner were then tested for the ability to inhibit growth and invasion of triple negative breast cancer (TNBC) cells (MDA-MB-231), sarcomatoid kidney cancer cells (RCJ-41T2) and pancreatic adenocarcinoma cells (MIAPaCa2). MTT assays were used to measure the effect of the compounds on tumor growth. 2D invasion assays and 3D tumor spheroid assays were employed to measure the effect of the analogs on invasion. One potent analog (SPX-009) was evaluated for the ability to suppress tumor growth and metastasis in mice bearing MDA-MB-231-luc breast cancer orthotopic xenografts. Results: Three of 53 analogs inhibited the enzymatic activity of QSOX1 at levels similar to the parent compound. However, one of those compounds, SPX-009, suppressed invasion of breast, kidney and pancreas tumor cells in 2D and 3D invasion assays at >10-fold lower concentrations than the parent compound (SBI-183). In a non-metastatic xenograft of kidney cancer SBI-183 suppressed primary kidney tumor growth by 51%, but in a metastatic xenograft breast cancer model (MDA-MB-231-luc TNBC), SBI-183 reduced lung metastasis by 76% compared to control. Human-mouse xenograft studies are ongoing with the more potent analog (SPX-009) and will also be presented. Conclusions: Chemical inhibitors of QSOX1 have a minor effect on tumor cell viability, but a major effect on tumor cell invasion in vitro and metastasis in vivo. This finding suggests that combining a QSOX1 inhibitor with a cytotoxic agent might provide a means to inhibit metastasis of cells that are resistant to cytotoxic agents. Citation Format: Amber Fifield, Thai H. Ho, Douglas O. Faigel, Sergei Svarovsky, Eduard Sergienko, Thomas C. Chung, Douglas F. Lake. Chemical inhibitors of quiescin sulfhydryl oxidase (QSOX1) suppress tumor invasion and metastasis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5323.

Abstract LB-133: Correlative analysis of pharmacokinetics and pharmacodynamics of RGX-104, a first-in-class Liver-X-Receptor (LXR) agonist, and clinical outcomes in patients with advanced solid tumors

Abstract RGX-104, a first-in-class small-molecule LXR agonist modulates innate immunity and cancer progression via transcriptional activation of ApoE. ApoE protein suppresses tumor cell invasion and angiogenesis, and also depletes circulating and tumoral myeloid derived suppressor cells (MDSC), leading to T cell activation.A multivariate approach was used to address pharmacokinetic (PK) and pharmacodynamic relationships of RGX-104 in a phase 1 dose escalation study in patients with relapsed/refractory solid tumors. The study entailed multiple escalation arms with RGX-104 as monotherapy and in combination with nivolumab, ipilimumab, or docetaxel. Various markers including intratumoral ApoE and its receptor LRP1 in biopsy specimens, gene expression of LXR-targets in whole blood, serum markers including cytokines and lipids, as well as immune cell types such as MDSC, CD8 T-cells, and neutrophils in peripheral blood from patients were monitored at several time points. PK metrics were tracked to assess dose response relationships. Clinical outcomes such as objective response, time to disease progression, and duration on therapy were used for exploratory correlative analyses. A generally dose dependent increase in steady state exposure to RGX-104 was observed among all cohorts; the lowest efficacious exposure among patients with partial response was ~14,000 ng*h/mL. Treatment with RGX-104 at doses ranging from 120 mg BID to 240 mg BID induced expression of LXR targets, ApoE [2.7X (p=0.008) to 7.1X (p=0.007)] and ABCA1 [ 6.3X (p=1.20E-03) to 7X (p=8.1E-04] over baseline in a generally dose-dependent manner as assessed in whole blood. Similarly, MDSC depletion, ranging from 70%-90% relative to baseline, was observed in patients treated with RGX-104 along with concomitant CD8 T-cell activation; similar effects were noted in patients in combination cohorts. A model to explore dose dependency of change in immune cell types suggested that baseline levels of MDSC were most predictive of the magnitude of MDSC reduction after treatment, and that favorable clinical outcomes correlate with the extent of MDSC reduction and T cell activation. Low baseline levels of tumoral ApoE were associated with greater clinical benefit, with almost all patients with stable disease or partial response exhibiting ApoE tumor positive score of ≤20%; these patients also exhibited low/negative PD-L1 (<1%) staining, revealing a target specific tumor biomarker and PD-L1 subset that could support prospective patient selection. These and additional markers will be tracked in expansion cohorts of RGX-104 in combination with pembrolizumab and carboplatin/pemetrexed for 1st line treatment of patients with metastatic non-small cell lung cancer (PD-L1 <1%) and in combination with docetaxel for 2nd line treatment of patients with small cell lung cancer. Citation Format: Monica Mita, Alan Mita, Erika Hamilton, Gerald S. Falchook, Michael Postow, Bartosz Chmielowski, Russell J. Schilder, James Strauss, Emerson Lim, Shubham Pant, Angela Jain, Oliver Rixe, Rebecca Redman, Kevin B. Kim, Tomislav Dragovich, R. Donald Harvey, Igor Puzanov, Nimisha Schneider, Renee Deehan, Tobi Guennel, Joe Lin, Sohail Tavazoie, Roger Waltzman, Eric Rowinsky, Michael Szarek, Subhasree Sridhar, Robert Busby, Narayan Lebaka, Celia Andreu, Isabel Kurth, David Darst, Masoud Tavazoie, Syed Raza, Robert Wasserman, Foster C. Gonsalves. Correlative analysis of pharmacokinetics and pharmacodynamics of RGX-104, a first-in-class Liver-X-Receptor (LXR) agonist, and clinical outcomes in patients with advanced solid tumors [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-133.

Suppression of cancer proliferation and metastasis by a versatile nanomedicine integrating photodynamic therapy, photothermal therapy, and enzyme inhibition

Cancer therapeutics are varied and target diverse processes in cancer progression. Photodynamic therapy (PDT), photothermal therapy (PTT), and the inhibition of pro-cancer proteases are non-invasive anticancer therapeutics that attract increasing attentions for their enhanced specificities and milder systemic toxicities compared to traditional therapeutics. These modalities offer advantages to compensate for the shortcomings of their counterparts. For instance, PDT or PTT efficiently eliminates locally confined tumor cells while exhibiting no effect on metastatic tumor cells. In contrast, the inhibition of pro-cancer proteases systemically suppresses the proliferation and metastasis of cancer cells but does not eradicate existing cancer cells. To synergize these therapeutics, we hereby report a versatile nanoparticle that integrates the effects of PDT, PTT, and enzyme-inhibition. This nanoparticle (CIKP-NP) was synthesized by covalently or non-covalently modifying a photothermal nanoparticle with a photosensitizer, a pro-cancer protease inhibitor, and an albumin-binding molecule. After confirming the PDT, PTT, albumin-binding, and enzyme-inhibition properties at the molecular level, we demonstrated that CIKP-NP killed tumor cells through PDT or PTT and suppressed tumor cell invasion through enzyme-inhibition. In addition, through a breast cancer xenograft mouse model, we demonstrated that CIKP-NP suppressed tumor growth by PDT or PTT effect. Notably, the synergism of PDT and PTT significantly enhanced its anticancer efficiency. Furthermore, CIKP-NP significantly suppressed cancer metastasis in a lung metastatic mouse model. Last, biodistribution and the in vivo retention of CIKP-NP confirmed the tumor-targeting property. Beyond demonstrating the anti-tumor and anti-metastatic efficacy of CIKP-NP, our study also suggests a new strategy to synergize multiple anticancer therapeutics.

Activation-Induced Cytidine Deaminase Expression Facilitates the Malignant Phenotype and Epithelial-to-Mesenchymal Transition in Clear Cell Renal Cell Carcinoma.

Although advances have been made in the development of antiangiogenesis targeted therapy and surgery, metastatic clear cell renal cell carcinoma (ccRCC) is still incurable. Activation-induced cytidine deaminase (AID) is mainly expressed in a variety of germ and somatic cells, and induces somatic hypermutation and class-switch recombination, playing a vital role in antibody diversification. We confirmed that AID was expressed at a higher level in ccRCC tissues than in the corresponding nontumor renal tissues. We explored the impact of AID on ccRCC proliferation, invasion, and migration. In 769-p and 786-0 cells, expression of an AID-specific short hairpin RNA significantly reduced AID expression, which markedly inhibited tumor cell invasion, proliferation, and migration. Previous studies showed that AID is associated with Wnt ligand secretion mediator (WLS/GPR177), cyclin-dependent kinase 4 (CDK4), and stromal cell-derived factor-1 (SDF-1/CXCL12) regulation, which was further confirmed in human ccRCC tissues. Therefore, we studied the relationship between AID and these three molecules, and the impact of AID on epithelial-to-mesenchymal transition in ccRCC. WLS/GPR177, SDF-1/CXCL12, and CDK4 were sensitive to 5-azacytidine (a DNA demethylation agent), which reverted the inhibition of carcinogenesis caused by AID repression. In summary, AID is an oncogene that might induce tumorigenesis through DNA demethylation. Targeting AID may represent a novel therapeutic approach to treat metastatic ccRCC.

MiR-625 Inhibits Tumor Cell Invasion, Migration and EMT by Negatively Regulating the Expression of Resistin in Non-Small Cell Lung.

PurposeTo investigate the role of miR-625 on the invasion, migration, and epithelial–mesenchymal transition (EMT) of non-small cell lung carcinoma (NSCLC) cells, and the related mechanisms.Materials and MethodsThe expression levels of miR-625 and Resistin mRNA in 80 pairs of NSCLC and para-cancerous lung tissues were analyzed by RT-PCR. The relationship between miR-625 and Resistin was predicted by bioinformatics and verified by a dual-luciferase gene reporter assay. NSCLC cells were transfected with Resistin plasmids, si-Resistin plasmids, miR-625 mimics, or miR-625 inhibitors, and proliferation, invasion, and migration were determined by CCK-8, Transwell, and wound scratch assays, respectively. EMT-related proteins were determined by Western blot assay. A xenograft model of NSCLC was established in nude mice to validate the in vitro findings.ResultsMiR-625 was significantly downregulated in NSCLC tissue compared to paired para-cancerous lung tissues, while Resistin was markedly increased in tumor tissue. The expression levels of miR-625 and Resistin were negatively correlated in NSCLC tissues, and high levels of Resistin correlated with greater tumor differentiation, more advanced clinical staging, and lymph node metastasis. Furthermore, Resistin was a target gene of miR-625, and the latter downregulated Resistin to inhibit the EMT, proliferation, invasion, and migration of NSCLC cells in vitro, likely via the PI3K/AKT/Snail signaling pathway. Finally, miR-625 also inhibited the tumorigenic effect of NSCLC cells in vivo by downregulating Resistin.ConclusionMiR-625 acts as a tumor suppressor in NSCLC and inhibits tumor cell invasion and metastasis by blocking the Resistin/PI3K/AKT/Snail pathway and by decreasing EMT.

Induction of posterior vitreous detachment (PVD) by non-enzymatic reagents targeting vitreous collagen liquefaction as well as vitreoretinal adhesion

Induction of posterior vitreous detachment (PVD) by pharmacologic vitreolysis has been largely attempted through the use of enzymatic reagents. Ocriplasmin has been the only FDA-approved clinical reagent so far. Several adverse effects of ocriplasmin have emerged, however, and the search for alternative PVD-inducing reagents continues. Since i) collagen forms an important structural component of the vitreous, and ii) strong vitreo-retinal adhesions exist between the cortical vitreous and the internal limiting membrane (ILM) of the retina, an effective PVD-inducing reagent would require both, vitreous liquefaction, and concurrent dehiscence of vitreoretinal adhesion, without being toxic to retinal cells. We designed a combination of two reagents to achieve these two objectives; a triple helix-destabilizing collagen binding domain (CBD), and a fusion of RGD (integrin-binding) tripeptide with CBD (RCBD) to facilitate separation of posterior cortical vitreous from retinal surface. Based on in vitro, ex-vivo, and in vivo experiments, we show that a combination of CBD and RCBD displays potential for safe pharmacologic vitreolysis. Our findings assume significance in light of the fact that synthetic RGD-containing peptides have already been used for inhibition of tumor cell invasion. Proteins such as variants of collagen binding domains could have extended therapeutic uses in the future.

Wnt Signaling Drives Prostate Cancer Bone Metastatic Tropism and Invasion

Wnt signaling has been implicated as a driver of prostate cancer-related osteoblast differentiation, and previous studies have linked modifications in Wnt function with the induction of tumor metastasis. A unique aspect of prostate cancer bone metastases in mouse models is their relative predilection to the hindlimb (femur) compared to the forelimb (humerus). Comparative gene expression profiling was performed within the humerus and femur from non–tumor-bearing mice to evaluate differences in the microenvironments of these locations. This revealed the relative overexpression of the Wnt signaling inhibitors WIF1 and SOST in the humerus compared to the femur, with increased WNT5A expression in femur bone marrow, suggesting a coordinated upregulation of Wnt signals within the femur compared to the humerus. Conditioned medium (CM) from bone marrow stromal cells (HS-5 cells) was used to mimic the bone marrow microenvironment, which strongly promoted prostate cancer cell invasion (3.3-fold increase in PC3 cells, P < .05; 7-fold increase in LNCaP cells, P < .05). WNT5A shRNA knockdown within the CM-producing HS-5 cells significantly decreased PC3 (56%, P < .05) and LNCaP (60%, P < .05) cell invasion. Similarly, preincubation of CM with WIF1 significantly blocked LNCaP cell invasion (40%, P < .05). shRNA-mediated knockdown of the Wnt receptors FZD4 and FZD8 also strongly inhibited tumor cell invasion (60% inhibition shFZD4, P < .05; 63% shFZD8, P < .05). Furthermore, small molecule inhibition of JNK, which is an important component of the noncanonical Wnt signaling pathway, significantly inhibited CM-mediated tumor invasion. Overall, this study reveals a role for Wnt signaling as a driver of prostate cancer bone metastatic tropism and invasion.

Cell active and functionally-relevant small-molecule agonists of calcitonin receptor.

The natural calcitonin (CT) receptor and its peptide agonists are considered validated targets for drug discovery. A small molecule agonist, SUN-B8155, has previously been shown to efficiently activate cellular CTR. Herein, we report the synthesis of a series of compounds (S8155 1-9) derived from SUN-B8155, and investigate the structural-functional relationship, bias properties and their cellular activity profile. We discover that the N-hydroxyl group from the pyridone ring is required for G protein activity and its affinity to the CT receptor. Among the compounds studied, S8155-7 exhibits improved G protein activity while S8155-4 displays a significant β-arrestin-2 signaling bias. Finally, we show that both S8155-4 and S8155-7 inhibit tumour cell invasion through CTR activation. These two compounds are anticipated to find extensive applications in chemical biology research as well drug development efforts targeting CT receptor.

SERPINE2 promotes esophageal squamous cell carcinoma metastasis by activating BMP4.

Metastasis is a major lethal cause of esophageal squamous cell carcinoma (ESCC) and confers a poor prognosis. Previous studies demonstrated that serpin family E member 2 (SERPINE2) is involved in tumor metastasis. However, the function and mechanism of SERPINE2 in ESCC metastasis remains unclear. In this study, we found that SERPINE2 was increased in ESCC and associated with tumor metastasis. SERPINE2 knockdown inhibited tumor cell invasion and lymph node and lung metastasis by inducing epithelial-mesenchymal transition (EMT). We identified a total of 410 differentially expressed genes in SERPINE2-knockdown cells by RNA-Seq analysis. Among them, bone morphogenetic protein 4 (BMP4) was significantly downregulated. Conversely, BMP4 was increased in SERPINE2-overexpressing cells. Inhibiting BMP4 could attenuate SERPINE2-induced migration and invasion. Moreover, SERPINE2 was positively correlated with clinical stage, tumor invasion depth and lymph node metastasis in ESCC patients. These findings suggest that SERPINE2 promotes tumor metastasis by activating BMP4 and could serve as a potential therapeutic target for clinical intervention in ESCC.

Role of Long Non-Coding RNA (LncRNA) LINC-PINT Downregulation in Cardiomyopathy and Retinopathy Progression Among Patients with Type 2 Diabetes.

BackgroundDespite the acknowledgement that LncRNA LINC-PINT may inhibit tumor cell invasion in human cancers, it is not yet determined when it comes to diabetes and its related complications.Material/MethodsThere were 244 patients with T2D and 126 healthy volunteers were admitted to People’s Hospital of Xinjiang Uygur Autonomous Region Hospital. Fasting blood (5 mL) was obtained from the patients and controls a day after admission. The diabetes patients’ fasting blood was extracted once every 6 months during follow-up. The total RNA was extracted and then used for detecting the expression of LINC-PINT.ResultsA comparison was made in this study, where LINC-PINT did not experience significant downregulation level in the majority of those suffering diabetes complications when in contrast to healthy controls, while LINC-PINT expression was found in diabetics. The follow-up study showed that LINC-PINT was downregulated in patients who developed cardiomyopathy and retinopathy or both but not in patients who developed other complications. Treatment with high glucose limited the extent of LINC-PINT expression in the ARPE-19 and AC16 cells. While the overexpression of LINC-PINT increased the viability of ARPE-19 and AC16 cells, siRNA-mediated silencing of LINC-PINT elicited the opposite effect.ConclusionsHence, we concluded that the overexpression of LINC-PINT may exhibit inhibitory effects on the progression of cardiomyopathy and retinopathy among patients with type 2 diabetes.

Adenosine Inhibits Ovarian Cancer Growth Through Regulating RhoGDI2 Protein Expression.

ObjectiveThis study aimed to investigate the effect of adenosine (Ado) on the growth of ovarian cancer and to explore the related mechanisms.MethodsThe effect of Ado on the proliferation of A2780 human ovarian cancer cells was examined according to the MTT method. Moreover, the nude mouse model of subcutaneous A2780 xenograft was constructed, and then, Ado and cisplatin were administered intraperitoneally to investigate the effect of Ado on tumor growth in vivo. Immunohistochemistry (IHC) was carried out to study the effect of Ado on the expression of Rho-specific guanine nucleotide dissociation inhibitor 2 (RhoGDI2) in the subcutaneous xenografts. Afterwards, the commercially constructed RhoGDI2 siRNA plasmid was transfected into A2780 cells, and tube formation assay was conducted to determine the effect of down-regulating RhoGDI2 expression on the regulation of angiogenesis in ovarian cancer by Ado. Besides, Western blotting was performed to detect the effect of RhoGDI2 down-regulation on the regulation of matrix metalloproteinase 2 (MMP-2), MMP-9, vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-β), tumor necrosis factor (TNF-α), and platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) expression in ovarian cancer cells by Ado.ResultsThe relative viability of cells subsequent to Ado treatment proved to be both concentration- and time dependent. IHC results showed that Ado evidently enhanced the RhoGDI2 protein expression. In addition, interference with RhoGDI2 outstandingly attenuated the ability of Ado to suppress tumor cell invasion and induce angiogenesis in vitro. Furthermore, molecular mechanism studies indicated that Ado remarkably inhibited the expression of MMP-2, MMP-9, VEGF, TGF-β, TNF-α, and CD31, while interference with RhoGDI2 restored the expression of the above-mentioned angiogenic factors.ConclusionAdo inhibits the growth of A2780 human ovarian cancer cells through inhibiting tumor cell invasion and angiogenesis in a RhoGDI2-dependent manner.

Low‐temperature plasma‐activated medium inhibited invasion and metastasis of melanoma cells via suppressing the Wnt/β‐catenin pathway

AbstractLow‐temperature plasma (LTP) has shown promising and potential applications in the field of biomedicine. The effects of the plasma‐activated medium (PAM) inhibiting tumor cell invasion and metastasis have been verified, but the associated molecular mechanisms are poorly understood. The aim of this study was to identify the anti‐invasion and antimetastasis effects and mechanism induced by PAM on B16 melanoma cells cultured in vitro. For this purpose, an atmospheric pressure plasma jet in helium was applied to generate PAM to treat B16 cells. Cell invasion and migration assays showed that PAM exerted an inhibitory effect on B16 cell invasion and migration in a time‐dependent manner. Then, detection of the invasion‐ and metastasis‐related proteins, including matrix metalloproteinase (MMP)‐2, MMP‐9, CD44, and E‐cadherin, showed that their changes accorded with the invasion and metastasis of the PAM‐treated B16 cells. Furthermore, the Wnt/β‐catenin pathway‐related proteins in PAM‐treated cells were measured, and the pathway was found to be suppressed by PAM. Finally, numerous specific reactive oxygen species (ROS) scavengers were applied to eliminate LTP‐induced ROS in PAM, and it was revealed that H2O2 played a critical role in these processes. These findings demonstrated that PAM exerted anti‐invasion and antimetastasis effects on B16 cells mainly by suppressing the Wnt/β‐catenin pathway, which consequently decreased the expressions of MMP‐9, MMP‐2, and CD44 via H2O2.

Receptor tyrosine kinase, RON, promotes tumor progression by regulating EMT and the MAPK signaling pathway in human oral squamous cell carcinoma

The receptor tyrosine kinase, recepteur d'origine nantais(RON), is known to be associated with the progression, metastasis, and prognosis of various types of cancers. Nevertheless, the role of RON in human oral squamous cell carcinoma(OSCC) is unclear. This study evaluated whether RON affects oncogenic behavior, oncogenic signaling pathways, and clinical outcomes, including survival, in human OSCC. Reverse transcription‑PCR, quantitative PCR, western blotting and immunohistochemical staining were used to determine mRNA and protein expression levels of RON. Cell invasion, migration and apoptosis assays were used to assess the functional effects of small interfering RNA‑mediated knockdown of RON or snail family transcriptional repressor2(SLUG). RON knockdown suppressed tumor cell invasion and migration and enhanced apoptosis in human OSCC cells. RON knockdown also decreased the phosphorylation of MAPK signaling proteins, such as ERK1/2, JNK and p38. In addition, RON knockdown suppressed the expression of the epithelial mesenchymal transition (EMT)‑related transcription factor, SLUG. SLUG knockdown blocked the enhancement of cell invasion and migration induced by macrophage‑stimulation protein (MSP)‑mediated RON activation in OSCC cells. The cell morphology was changed to spindle‑like shape under MSP‑mediated RON activation in OSCC cells. RON was overexpressed in both fresh and paraffin‑embedded human OSCC tissues. Taken together, these results indicate that RON contributed to tumor progression by regulating the EMT‑related factor, SLUG, and the MAPK pathway in OSCC. This study may provide a theoretical basis for the application of RON‑targeting agents, currently being studied in various cancer fields, for the treatment of OSCC.

Deubiquitinase USP9X regulates the invasion of prostate cancer cells by regulating the ERK pathway and mitochondrial dynamics.

The ubiquitin-specific protease 9X (USP9X) is a conserved deubiquitinase that has been investigated in several types of human cancer. However, the clinical significance and the biological roles of USP9X in prostate cancer remain unexplored. In the present study, an investigation into the expression and clinical significance of USP9X in prostate cancer revealed that USP9X expression was downregulated in prostate cancer tissues compared with that in healthy tissues. In addition, decreased USP9X expression was associated with a higher Gleason score and local invasion. Depletion of USP9X in prostate cancer LNCaP and PC-3 cells by small interfering RNA promoted cell invasion and migration. Furthermore, USP9X depletion upregulated matrix metalloproteinase 9 (MMP9) and the phosphorylation of dynamin-related protein 1 (DRP1). Notably, a significant increase in phosphorylated extracellular signal-regulated kinase (ERK), an upstream activator of MMP9 and DRP1, was observed. To investigate whether ERK activation was able to increase MMP9 protein levels and induce DRP1 phosphorylation, an ERK inhibitor was used, demonstrating that ERK-mediated MMP9 production and change in mitochondrial function was critical for the biological function of USP9X in prostate cancer cells. In conclusion, the present study demonstrated that USP9X is downregulated in prostate cancer and functions as an inhibitor of tumor cell invasion, possibly through the regulation of the ERK signaling pathway.

Forkhead‑boxA1 regulates tumor cell growth and predicts prognosis in colorectal cancer.

Forkhead boxA1 (FOXA1) functions as a tumor suppressor gene or an oncogene in various types of cancer; however, the distinct function of FOXA1 in colorectal cancer is unclear. The present study aimed to evaluate whether FOXA1 affects the oncogenic behavior of colorectal cancer cells, and to investigate its prognostic value in colorectal cancer. The impact of FOXA1 on tumor cell behavior was investigated using small interfering RNA and the pcDNA6‑myc vector in human colorectal cancer cell lines. To investigate the role of FOXA1 in the progression of human colorectal cancer, an immunohistochemical technique was used to localize FOXA1 protein in paraffin‑embedded tissue blocks obtained from 403patients with colorectal cancer. Tumor cell apoptosis and proliferation were evaluated using a terminal deoxynucleotidyl transferase‑mediated dUTP nick‑end labeling assay and Ki‑67 immunohistochemical staining, respectively. FOXA1 knockdown inhibited tumor cell invasion in colorectal cancer cells, and induced apoptosis and cell cycle arrest. FOXA1 knockdown activated cleaved caspase‑poly(ADP‑ribose) polymerase, upregulated the expression of p53 upregulated modulator of apoptosis, and downregulated BH3 interacting domain death agonist and myeloid cell leukemia‑1, leading to the induction of apoptosis. FOXA1 knockdown increased the phosphorylation level of signal transducer and activator of tran-scription‑3. By contrast, these results were reversed following the overexpression of FOXA1. The overexpression of FOXA1 was associated with differentiation, lymphovascular invasion, advanced tumor stage, depth of invasion, lymph node metastasis and poor survival rate. The mean Ki‑67 labeling index value of FOXA1‑positive tumors was significantly higher than that of FOXA1‑negative tumors. However, no significant association was observed between the expression of FOXA1 and the mean apoptotic index value. These results indicate that FOXA1 is associated with tumor progression via the modulation of tumor cell survival in human colorectal cancer.

Research progress of exosomes in epithelial-mesenchymal transition

Exosome, a membranous vesicle with biological activity, not only transmits active substances between cells but also transfers information between cells to participate in cell communication. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire migratory and invasive properties to become mesenchymal stem cells. EMT is essential for the development of a spectrum of diseases. Studies have shown that exosomes have dual effects on EMT to, on the one hand, promote EMT and tumor cell invasion and metastasis and accelerate angiogenesis and tumor growth; on the other hand, exosomes can suppress tumor cell invasion, inhibit fibrosis of the heart, liver and kidney, and improve myocardial infarction by inhibiting EMT. Exosomes modulate EMT-related signaling pathways by carrying EMT-related proteins or miRNA to exert their bi-directional regulatory effects.

Abstract P2-01-24: Sulindac and triple negative breast cancer progression

Abstract In 2018, a total of 266,120 new cases and 40,920 deaths from breast cancer in the United States were estimated by the American Cancer Society. Breast cancer is the most common malignancy and the second leading cause of death among American women. In this study, we will focus on triple negative breast cancer (TNBC), which is viewed by oncologists as a problematic and unpredictable sub-category of breast cancer because of higher rates of recurrence and poorer prognosis. TNBC accounts for up to 20% of all breast cancers and is highly prevalent in minority and young women. On average, 70% of women with metastatic TNBC die within 5 years, regardless of chemotherapy or other treatments. As such, there is an urgent medical need to develop more effective drugs to manage this deadly disease that already raised a health disparity concern, especially in the State of Louisiana. Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used drugs for the treatment of pain, fever, and inflammation. Epidemiological studies have reported that the long term use of NSAIDs can prevent the occurrence multiple types of cancers, including breast cancer. However, their long term use for chemoprevention is not recommended because of toxicities associated with cyclooxygenase (COX) inhibition and the suppression of physiologically important prostaglandins. Our results show that the NSAID, sulindac sulfide (SS) and its non-COX inhibitory derivatives, can significantly inhibit the growth of the major subtypes of TNBC cells (basal-like, mesenchymal, and luminal). In addition, the compounds significantly inhibit tumor cell invasion. The animal experiments using Patient Derived Xenograft models supported the in vivo efficacy of these drugs. While studying the mechanism, we found that four oncogenic miRNAs, miR-10b, miR-17, miR-21, and miR-9 can be downregulated by SS and derivatives, and they were reported to promote tumor metastasis exclusively. Therefore, we conclude that those oncogenic miRNAs are involved in anti-metastatic activities of SS and its new non-COX inhibitory derivatives in TNBC. Citation Format: Xi Y, Yi B, Riker A. Sulindac and triple negative breast cancer progression [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-24.