Reduced Cancer Cell Migration Research Articles

Total Synthesis and Target Identification of the Curcusone Diterpenes.

The curcusone natural products are complex diterpenes featuring a characteristic [6-7-5] tricyclic carbon skeleton similar to the daphnane and tigliane diterpenes. Among them, curcusones A-D demonstrated potent anticancer activity against a broad spectrum of human cancer cell lines. Prior to this study, no total synthesis of the curcusones was achieved and their anticancer mode of action remained unknown. Herein, we report our synthetic and chemoproteomics studies of the curcusone diterpenes which culminate in the first total synthesis of several curcusone natural products and identification of BRCA1-associated ATM activator 1 (BRAT1) as a cellular target. Our efficient synthesis is highly convergent, builds upon cheap and abundant starting materials, features a thermal [3,3]-sigmatropic rearrangement and a novel FeCl3-promoted cascade reaction to rapidly construct the critical cycloheptadienone core of the curcusones, and led us to complete the first total synthesis of curcusones A and B in only 9 steps, C and D in 10 steps, and dimericursone A in 12 steps. The chemical synthesis of dimericursone A from curcusones C and D provided direct evidence to support the proposed Diels-Alder dimerization and cheletropic elimination biosynthetic pathway. Using an alkyne-tagged probe molecule, BRAT1, an important but previously "undruggable" oncoprotein, was identified as a key cellular target via chemoproteomics. We further demonstrate for the first time that BRAT1 can be inhibited by curcusone D, resulting in impaired DNA damage response, reduced cancer cell migration, potentiated activity of the DNA damaging drug etoposide, and other phenotypes similar to BRAT1 knockdown.

Inhibitory effects on chondrosarcoma cell metastasis by Senna alata extract

BackgroundSenna alata L. Roxb or candle bush is a traditional medicinal plant with a wide range of biological activities including anti-inflammatory, antimicrobial and antifungal. Leaf extract of S. alata showed the anti-tumor activity in various cancer cell lines. In this study, we focused on the inhibitory mechanism of S. alata extract (SAE) on cancer metastasis including cell migration, cell invasion and signaling pathways in chondrosarcoma SW1353 cells. PurposeThis study aimed to evaluate the anti-metastatic mechanisms of Senna alata extract on chondrosarcoma SW1353 cells. MethodsScreening for phytochemicals in biologically active fraction of SAE was analysed by 1H NMR spectroscopy. Cell viability and cytoxicity were determined by using MTT assay. Cell migration was observed by scratch wound healing and transwell migration assay. Cell invasion and cell adhesion assay were examined by Matrigel coated transwell chambers or plates. The expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), MAPKs and PI3K/Akt signaling pathways and NF-κB were detected by Western blot analysis. ResultsThe SAE treatment at the sub-cytoxic and non-cytotoxic concentrations significantly inhibited cell migration, cell invasion and cell adhesion of SW1353 cells in a dose-dependent manner. The results from Western blot analysis showed decreased MMP-2 and MMP-9 expression, while increased TIMP-1 and TIMP-2 expression in SAE treated cells. Moreover, SAE suppressed phosphorylation of ERK1/2, p38 and Akt but decreased NF-κB transcription factor expression in SW1353 cells. ConclusionThese results revealed that SAE could reduce MMP-2 and MMP-9 expression by downregulation of NF-κB which is downstream of MAPKs and PI3K/Akt signaling pathway in SW1353 cells resulting in reduced cancer cell migration and invasion. Therefore, SAE may have the potential use as an alternative treatment of chondrosarcoma metastasis.

CD9 Upregulation-Decreased CCL21 Secretion in Mesenchymal Stem Cells Reduces Cancer Cell Migration.

Tetraspanin CD9 is widely expressed on various cell types, such as cancer cells and mesenchymal stem cells (MSCs), and/or cell-released exosomes. It has been reported that exosomal CD9 plays an important role in intercellular communications involved in cancer cell migration and metastasis. However, reports on the effect of the CD9 of MSCs or MSC-derived exosomes on cancer cell migration are still lacking. In this study, using a transwell migration assay, we found that both dextran-coated iron oxide nanoparticles (dex-IO NPs) and ionomycin stimulated exosomal CD9 expression in human MSCs (hMSCs); however, hMSCs could not deliver them to melanoma cells to affect cell migration. Interestingly, a reduced migration of melanoma cell line was observed when the ionomycin-incubated hMSC-conditioned media but not dex-IO NP-labeled hMSC-conditioned media were in the bottom chamber. In addition, we found that dex-IO NPs decreased cellular CD9 expression in hMSCs but ionomycin increased this. Simultaneously, we found that ionomycin suppressed the expression and secretion of the chemokine CCL21 in hMSCs. The silencing of CD9 demonstrated an inhibitory role of cellular CD9 in CCL21 expression in hMSCs, suggesting that ionomycin could upregulate cellular CD9 to decrease CCL21 expression and secretion of hMSCs, which would reduce the migration of B16F10, A549 and U87MG cancer cell lines due to chemoattraction reduction of CCL21. The present study not only highlights the important role of bone marrow-derived hMSCs’ CD9-mediated CCL21 regulation in cancer bone metastasis but also suggests a new distinct pharmaceutical strategy for prevention or/and therapy of cancer metastasis.

Abstract 1761: Examination of therapeutic potential of epigenetic modulation by dual HDAC-LSD1 inhibition in murine models of triple negative breast cancer (TNBC)

Abstract This study examines the effects of the epigenetic modulator 4SC-202, a dual histone deacetylase (HDAC) /lysine-specific histone demethylase 1A (LSD1) small molecule inhibitor, on tumor growth and metastasis in a mouse model of breast cancer. 4SC-202 differs from clinically available HDAC inhibitors such as Vorinostat (SAHA) by specifically targeting class I HDACs including HDAC1, HDAC2, and HDAC3 and the histone demethylase LSD1. The hypothesis to be examined is that epigenetic modulation via dual inhibition of HDAC1 and LSD1 improves disease control in breast cancer. In vitro data indicates that 4SC-202 is significantly cytotoxic and cytostatic to the highly metastatic murine Triple Negative Breast Cancer (TNBC) murine model 4T1 and the human TNBC cell line MDA-MB-231 and reduces cancer cell migration. In vivo studies conducted in the syngeneic 4T1 model which closely mimics human TNBC in terms of sites of metastasis, show increased necrosis in 4T1 tumors, reduced tumor burden in vivo as compared to Vorinostat treatment, and significantly reduced metastasis. Furthermore, multiple studies in different cell types indicate that the mechanism of action of 4SC-202 may involve effects on cancer stem cells, which are able to self-renew and form metastatic lesions. It has been shown that a marker of cancer stem cells (CSC's) in breast cancer is high aldehyde dehydrogenase (ALDH) activity and that ALDH high cells mediate metastasis. In the 4T1 syngeneic mouse model of breast cancer, inhibition of ALDH activity suppresses stem-like cell properties. Preliminary data suggests 4SC-202 substantially reduces the ALDH high 4T1 cancer stem population. Transcriptome bulk RNA -sequencing analysis from 4T1 tumors reveal changes in metastatic related pathways in 4SC-202 treated tumors, including significant changes to the expression levels of genes implicated in focal adhesion and ECM-receptor interaction pathways. Furthermore, 4SC-202 appears to alter expression of cytokines which serve as chemokines, potentially leading to increased expression of tumor infiltrating lymphocytes. In summary, treatment of a highly metastatic murine model of TNBC with 4SC-202 significantly reduces metastasis, and warrants further preclinical studies in conjunction with standard of care chemotherapy treatment. Citation Format: Shanta M. Messerli, Mariah M. Hoffman, Jessica S. Zylla, Etienne Gnimpieba, Keith W. Miskimins. Examination of therapeutic potential of epigenetic modulation by dual HDAC-LSD1 inhibition in murine models of triple negative breast cancer (TNBC) [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 1761.

Abstract 5246: Disulfiram anticancer metabolite, dithiocarb-copper complex, demonstrates anti-neoplastic activity against hypermutated colorectal cancers

Abstract Introduction: Colorectal cancer (CRC) is the third leading cause of cancer related deaths in the United States. It was responsible for about 51,000 deaths during 2019. Surgical resection and systemic chemotherapy are standard approaches to treat both localized and metastatic CRC (mCRC). However, the effect of the chemotherapy depends on the characteristics of the individual tumor, for instance CRC subtypes with a microsatellite instability (MSI) tend to have better prognosis and response to both chemotherapy and immune check-point inhibition. Recently, Disulfiram's anti-cancer activity was explored and its metabolite ditiocarb-copper complex (CuET) was found to have high anti-cancer activity. The mechanism of action of CuET was proposed to act through p97 segregase adaptor NPL4 and activation of endoplasmic reticulum stress leading to preferential apoptosis of cancer cells. Since altered protein degradation pathway is targeted by CuET, this compound might display high efficacy in highly mutated colorectal cancers. Methods: To assess CuET anti-cancer activity in vitro, we performed survival curve assays and colony-formation assays in both murine hypermutated colorectal cancer cell line MC-38 as well as in human KRAS mutant and MSI HCT116 cell line. We also evaluated anti-metastatic effect of CuET on both cell lines through migration-invasion assays in Boyden chamber setting. We assessed in vivo efficacy of systemic treatment with CuET alone or in combination with irinotecan, against MC-38 model in immunocompetent C57BL/6 mice. We characterized tumor growth, mice survival and tumor histopathology. Results: Our results demonstrate that CuET displays cytotoxicity in MC-38 and HCT116 cells at very low doses with respective IC50 of 46nM and 88nM. CuET also significantly reduces the ability of both cell lines to grow and form colonies under sustained treatment. Additionally, CuET is effective in significantly reducing cancer cell migration and invasion through porous membrane in vitro. Furthermore, systemic treatment with CuET significantly reduced tumor growth in mice and prolonged survival when compared to controls. Conclusion: CuET demonstrates cytotoxic activity against hypermutated colorectal cancer cells both in vitro and in vivo and should be further investigated in clinical trials. Citation Format: Daciana Catalina Dumut, Juan B. De Sanctis, Martin Mistrik, Zdenek Skrott, Petr Dzubak, Jiri Bartek, Marian Hajduch, Danuta Radzioch. Disulfiram anticancer metabolite, dithiocarb-copper complex, demonstrates anti-neoplastic activity against hypermutated colorectal cancers [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 5246.

ATIP3 deficiency facilitates intracellular accumulation of paclitaxel to reduce cancer cell migration and lymph node metastasis in breast cancer patients

Taxane-based chemotherapy is frequently used in neoadjuvant treatment of breast cancer patients to reduce tumor growth and lymph node metastasis. However, few patients benefit from chemotherapy and predictive biomarkers of chemoresistance are needed. The microtubule-associated protein ATIP3 has recently been identified as a predictive biomarker whose low levels in breast tumors are associated with increased sensitivity to chemotherapy. In this study, we investigated whether ATIP3 deficiency may impact the effects of paclitaxel on cancer cell migration and lymph node metastasis. Expression levels of ATIP3 were analyzed in a cohort of 133 breast cancer patients and classified according to lymph node positivity following neoadjuvant chemotherapy. Results showed that low ATIP3 levels are associated with reduced axillary lymph node metastasis. At the functional level, ATIP3 depletion increases cell migration, front-rear polarity and microtubule dynamics at the plus ends, but paradoxically sensitizes cancer cells to the inhibitory effects of paclitaxel on these processes. ATIP3 silencing concomitantly increases the incorporation of fluorescent derivative of Taxol along the microtubule lattice. Together our results support a model in which alterations of microtubule plus ends dynamics in ATIP3-deficient cells may favor intracellular accumulation of paclitaxel, thereby accounting for increased breast tumor sensitivity to chemotherapy.

Brn3a/Pou4f1 Functions as a Tumor Suppressor by Targeting c-MET/STAT3 Signaling in Thyroid Cancer.

Brn3a/Pou4f1 is a class IV POU domain-containing transcription factor and has been found to be expressed in a variety of cancers. However, the mechanism and action of Brn3a in thyroid cancer has not been investigated. To investigate the role of Brn3a in thyroid cancer progression and its clinical implication. We examined Brn3a expression status in patients with thyroid cancer and analyzed relationships between Brn3a expression and clinicopathological findings using The Cancer Genome Atlas (TCGA) database. For functional in vitro analysis, proliferation, migration, invasion assay, and Western blotting were performed after overexpression or suppression of Brn3a. The promoter hypermethylation of Brn3a was found in patients with aggressive thyroid cancer and Brn3a was downregulated in tissues of patients with thyroid cancer. In TCGA database, the low-Brn3a-expression group revealed a more aggressive phenotype, including T stage and extrathyroid extension when compared with the high-Brn3a-expression group. Overexpression of Brn3a suppressed cell migration and invasion via regulation of epithelial-mesenchymal transition (EMT)-associated proteins in thyroid cancer cell lines. Brn3a overexpression also downregulated signal transducer and activator of transcription 3 (STAT3) signaling through suppression of tyrosine-protein kinase Met (c-MET). In contrast, knockdown of Brn3a by small interfering ribonucleic acid (siRNA) significantly increased cell migration and invasion through upregulation of c-MET/STAT3. These results imply that Brn3a suppresses tumor metastasis via c-MET/STAT3 inhibition and EMT suppression in thyroid cancer. Our findings show that Brn3a is a potential tumor suppressor that leads to reduced cancer cell migration and invasion in thyroid cancer. Elucidation of the Brn3a-regulated cancer pathways may therefore provide novel therapeutic strategies to control thyroid cancer metastasis.

Extracts of edible, medicinal Thai plants inhibit the human breast cancer cells

Purpose: To evaluate the effects of ten edible, medicinal Thai plant extracts on MCF-7 cell viability and cell migration, as well as their mechanism(s) of action.
 Methods: Ethanolic plant extracts of ten edible, medicinal plants were tested for their cytotoxicity against MCF-7 cells using sulforhodamine B (SRB). To investigate the cytotoxic mechanism(s) of action of these extracts, the study was examined gene expression and protein expression by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting. Cell migration was studied by wound healing assay.
 Results: Four of the ten test extracts were potently cytotoxic, Careya sphaerica (CS), Azadirachta indica (AI), Piper nigrum (PN) and Oroxylum indicum (OI) with half maximal inhibitory concentrations (IC50) less than 100 μg/mL. All four extracts stimulated ROS overgeneration, increased caspase 3 activity and decreased growth-related gene expression including cdk2, cdk4, cdk6, cyclin D1 and cyclin E. Furthermore, the extracts significantly enhanced cyclin-dependent kinase inhibitor (CDKI) p21 levels and activated cancer cell death. The four extracts, CS, AI, PN and OI, also significantly reduced cancer cell migration, with PN being the most potent.
 Conclusion: Extract of the edible plants CS, AI, PN and OI have in vitro anticancer activity and are promising starting points for the development of breast cancer drugs.
 Keywords: Careya sphaerica (CS), Azadirachta indica (AI), Piper nigrum (PN), Oroxylum indicum (OI), Breast cancer, Cell death

Synthesis of crystalline zinc hydroxystannate and its thermally driven amorphization and recrystallization into zinc orthostannate and their phase-dependent cytotoxicity evaluation

Engineered metal-oxide nanoparticles have greatly been used in various bio-applications, but their physicochemical properties change dramatically within a bio-system. Therefore, the development of new metal-oxide nanoparticles and proper understanding of their toxicity profile in bio-environment are very important for advancement of cancer-related diagnostic and therapeutic approaches. Nanostructured wide-bandgap semiconductors ZnSn(OH)6 and Zn2SnO4 are fabricated by one-pot hydrothermal synthesis and tested for the first time in anti-cancer treatments. The crystalline zinc-hydroxystannate is converted by high-temperature annealing into amorphous and then crystalline zinc-orthostannate, as confirmed by Rietveld refinement analyses. A dose-dependent cytotoxicity is observed when human cervical carcinoma cell lines are exposed to these nanomaterials, mainly due to the elevation of intracellular reactive-oxygen-species levels in the treated cells, which leads to oxidative stress and cell damage. The crystalline phases of the nanomaterials reveal better cell-killing efficacy due to the overlap of the conduction-band energy levels with the cellular redox potential, leading to favorable electron transfer from the biological redox couples to the conduction-band of the semiconductor nanoparticles, thus producing more reactive-oxygen-species for cell damage. Importantly, this higher reactive-oxygen-species production by the crystalline samples significantly reduces cancer cell migration and proliferation and decreases metastasis, which remains an unmet challenge in cancer therapy.

Repurposing Penfluridol in Combination with Temozolomide for the Treatment of Glioblastoma.

Despite the presence of aggressive treatment strategies, glioblastoma remains intractable, warranting a novel therapeutic modality. An oral antipsychotic agent, penflurido (PFD), used for schizophrenia treatment, has shown an antitumor effect on various types of cancer cells. As glioma sphere-forming cells (GSCs) are known to mediate drug resistance in glioblastoma, and considering that antipsychotics can easily penetrate the blood-brain barrier, we investigated the antitumor effect of PFD on patient-derived GSCs. Using five GSCs, we found that PFD exerts an antiproliferative effect in a time- and dose-dependent manner. At IC50, spheroid size and second-generation spheroid formation were significantly suppressed. Stemness factors, SOX2 and OCT4, were decreased. PFD treatment reduced cancer cell migration and invasion by reducing the Integrin α6 and uPAR levels and suppression of the expression of epithelial-to-mesenchymal transition (EMT) factors, vimentin and Zeb1. GLI1 was found to be involved in PFD-induced EMT inhibition. Furthermore, combinatorial treatment of PFD with temozolomide (TMZ) significantly suppressed tumor growth and prolonged survival in vivo. Immunostaining revealed decreased expression of GLI1, SOX2, and vimentin in the PFD treatment group but not in the TMZ-only treatment group. Therefore, PFD can be effectively repurposed for the treatment of glioblastoma by combining it with TMZ.

Expression and prognostic relevance of calcium calmodulin-dependent protein kinase kinase 2 (CaMKK2) in chronic lymphocytic leukemia (CLL).

e19002 Background: CaMKK2 has restricted tissue expression in humans, regulates diverse cell functions, and is overexpressed in several human malignancies. Blocking its function reduces cancer cell migration and survival in vitro and in vivo. The relevance of CaMKK2 signaling in lymphoma is uncertain, however. Here, we sought to characterize CaMKK2 expression in CLL, as well as its predictive variables and prognostic relevance. Methods: B cell samples from 39 CLL patients and 4 healthy donors were obtained from a biorepository at our institution through an active protocol. Commercially available kits were used for RNA isolation, cDNA generation, and RT-PCR. The Kolmogorov-Smirnov test was used to compare CaMKK2 expression between patients and donors. Regression analysis was used to identify independent predictors of CaMKK2 expression. Treatment-free survival was estimated using the Kaplan-Meier method. Results: CaMKK2 mRNA was standardized to actin and overexpressed in CLL cells v. healthy donor B cells (2.27 - 11.83 x 10-2 v. 0.93 - 1.67 x 10-2, p = 0.0014). Nine variables were evaluated for possible association, including age, gender, race, WBC and monocyte count, IGVH mutation status, FISH panel, Zap70 and CD38 status. By univariate analysis, unmutated IGVH and African-American race were associated with higher CaMKK2 expression (p = 0.0023 and 0.0238). Race was identified as a potential confounder for IGVH mutation status and vice versa. In a multivariate model, only IGVH mutation status predicted for CaMKK2 expression. Patients in the highest quartile of CaMKK2 expression had lower 2 year treatment-free survival compared with all others (10.7% v. 59.2%, p = 0.0054). Conclusions: CaMKK2 mRNA is over-expressed in CLL cells relative to normal B cells. Higher CaMKK2 expression in CLL may be associated with unmutated IGVH and African-American race and predict shorter time to treatment. Our analyses are limited by all unmutated IGVH patients receiving early treatment in our cohort. [Table: see text]

Bioanalytical Method Development for the Detection of the Rac/Cdc42 Inhibitor MBQ‐167 in Mouse Tissue

Metastatic breast cancer is the second most common cancer in US women. The mortality rate has decreased approximately 40% in the last 25 years due to advancement in treatment and diagnostics. However, it is estimated that 20–30% of all breast cancer patients will develop metastatic breast cancer. Therefore, there is a need to develop targeted therapeutics to reduce cancer cell migration and subsequent metastasis. The novel small molecule MBQ‐167 inhibits Rac and Cdc‐42, proteins involved in cancer cell growth, migration and invasion. In vivo studies have shown that MBQ‐167 inhibits mammary tumor growth and metastasis in immunocompromised mice by ~90% (Humphries‐Bickley, et al., 2017). However, to continue validating this drug for FDA approval, it is necessary to study the pharmacokinetic profile of the drug, which includes elucidating the tissue distribution of the compound in the body. Hence, it is necessary to develop a rapid and sensitive method to quantify MBQ‐167 in tissues. The purpose of this study was to develop and validate a method for the quantification of MBQ‐167 in mouse tissues using Supercritical fluid chromatography coupled with electrospray ionization tandem mass spectrometry (SFC‐MS/MS). Mouse livers were homogenized, spiked with MBQ‐167, and liquid‐liquid extractions were performed with different organic solvents (heptane, ethyl acetate, 2‐propanol, toluene, and acetonitrile), in order to determine the optimal sample preparation method to selectively separate the drug MBQ‐167 from endogenous material in mouse tissue. Separation was performed on an ACQUITY UPC2BEH (3.0 × 100 mm, 1.7 μm) column at 40 °C with a mobile phase consisting of CO2 and methanol 0.1 % formic acid (95:5, v/v) at a flow rate of 1 mL/min. A tandem triple quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM) mode. High recovery of MBQ‐167 (> 65%) and lower matrix effects were observed upon extraction with heptane:ethyl acetate (1:1). Consistent recovery was observed in other tissues such as kidney, lungs and heart. The method was sensitive with a lower limit of quantification (LLOQ) of 10 ng/mL. Linearity was observed over the concentration range of 10–1000 ng/mL. The data obtained supports the use of SFC‐MS/MS as a highly specific method to evaluate the tissue distribution of MBQ‐167 in mice.Support or Funding InformationThis study is supported by MARC grant NIH/NIGMS 5T34GM007821‐39 (to GRG) and NIGMS‐RISE 25 GM061838 (to MM).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

EGFL6 promotes breast cancer by simultaneously enhancing cancer cell metastasis and stimulating tumor angiogenesis.

EGFL6, a member of the EGF-like superfamily, plays an important role during embryonic development and has been implicated in promotion of tumor angiogenesis without affecting wound healing. There is very little known about the function of EGFL6 in cancer cells. Here, we investigated whether EGFL6 plays a direct role in cancer cells in addition to the promotion of tumor angiogenesis. Our study showed that EGFL6 promoted epithelial-mesenchymal transition (EMT) and stemness of breast cancer cells and increased cell migration and invasion in cell culture studies. We also found that EGFL6 reduced apoptotic signaling in cancer cells and promoted tumor growth in vivo. Importantly, expression of EGFL6 in cancer cells and tumor endothelial cells not only increased tumor angiogenesis but also promoted migration of cancer cells. Such dual engagement of cancer and stromal cells suggests crosstalk mediated by EGFL6 in the tumor microenvironment. Blockade of EGFL6 using our novel anti-EGFL6 monoclonal antibody significantly reduced cancer cell migration, tumor angiogenesis, and tumor growth in mouse xenograft tumor models. Silencing EGFL6 mRNA by shRNA transfection of cancer cells also significantly reduced cancer cell migration, tumor angiogenesis, and tumor growth in mouse xenograft tumor models. Taken together, the results of this study indicate that targeting EGFL6 is a unique strategy for inhibiting both cancer cell metastasis and tumor angiogenesis.

Breast Cancer, Chemokines, And Metastasis: A Search for Decoy Ligands of the CXCR4 Receptor

Breast cancer (BC) is the leading cause of cancer-related deaths in young to middle-aged women worldwide. Moreover, the survival rate in BC-patients is only 20% when associated with metastatic disease. The high mortality rate observed in BC women with metastatic disease has precipitated a major challenge revealing an unmet need to develop new therapeutic strategies in treating metastatic cancer. One such approach has involved utilization of chemokines and their receptors as therapeutic targets for cancer metastasis. It has been established that a definitive correlation exists between overexpressed CXCR4 malignant cell receptors and cancer cell growth, invasion, and migration. It is also widely accepted that the CXCR4 receptor, complexed to its CXCL12 ligand, plays a major role in establishing migratory pathway gradients for cancer cells migrating to distant tissues/organ sites. It would follow that chemokine decoy ligands, such as peptide antagonists and inhibitors, could serve to induce receptor blockade and impede subsequent intracellular signaling. Such ligands, synthetic and natural, reportedly contribute to reducing cancer cell growth, invasion, adherence, and migration. The present commentary describes several existing synthetic CXCR4 receptor-ligand peptide antagonists and presents a strategy to develop naturally-occurring human protein-derived peptide candidates.

Regulation of antitumor miR-144-5p targets oncogenes: Direct regulation of syndecan-3 and its clinical significance.

In the human genome, miR‐451a, miR‐144‐5p (passenger strand), and miR‐144‐3p (guide strand) reside in clustered microRNA (miRNA) sequences located within the 17q11.2 region. Low expression of these miRNAs is significantly associated with poor prognosis of patients with renal cell carcinoma (RCC) (miR‐451a: P = .00305; miR‐144‐5p: P = .00128; miR‐144‐3p: P = 9.45 × 10−5). We previously reported that miR‐451a acted as an antitumor miRNA in RCC cells. Involvement of the passenger strand of the miR‐144 duplex in the pathogenesis of RCC is not well understood. Functional assays showed that miR‐144‐5p and miR‐144‐3p significantly reduced cancer cell migration and invasive abilities, suggesting these miRNAs acted as antitumor miRNAs in RCC cells. Analyses of miR‐144‐5p targets identified a total of 65 putative oncogenic targets in RCC cells. Among them, high expression levels of 9 genes (FAM64A, F2,TRIP13,ANKRD36,CENPF,NCAPG,CLEC2D,SDC3, and SEMA4B) were significantly associated with poor prognosis (P < .001). Among these targets, expression of SDC3 was directly controlled by miR‐144‐5p, and its expression enhanced cancer cell aggressiveness. We identified genes downstream by SDC3 regulation. Data showed that expression of 10 of the downstream genes (IL18RAP,SDC3,SH2D1A,GZMH,KIF21B,TMC8,GAB3,HLA‐DPB2,PLEK, and C1QB) significantly predicted poor prognosis of the patients (P = .0064). These data indicated that the antitumor miR‐144‐5p/oncogenic SDC3 axis was deeply involved in RCC pathogenesis. Clustered miRNAs (miR‐451a, miR‐144‐5p, and miR‐144‐3p) acted as antitumor miRNAs, and their targets were intimately involved in RCC pathogenesis.

First evidence of SGPL1 expression in the cell membrane silencing the extracellular S1P siren in mammary epithelial cells

The bioactive lipid sphingosine-1-phosphate (S1P) is a main regulator of cell survival, proliferation, motility, and platelet aggregation, and it is essential for angiogenesis and lymphocyte trafficking. In that S1P acts as a second messenger intra- and extracellularly, it might promote cancer progression. The main cause is found in the high S1P concentration in the blood, which encourage cancer cells to migrate through the endothelial barrier into the blood vessels. The irreversible degradation of S1P is solely caused by the sphingosine-1-phosphate lyase (SGPL1). SGPL1 overexpression reduces cancer cell migration and therefore silences the endogenous S1P siren, which promotes cancer cell attraction—the main reason for metastasis. Since our previous metabolomics studies revealed an increased SGPL1 activity in association with successful breast cancer cell treatment in vitro, we further investigated expression and localization of SGPL1. Expression analyses confirmed a very low SGPL1 expression in all breast cancer samples, regardless of their subtype. Additionally, we were able to prove a novel SGPL expression in the cytoplasm membrane of non-tumorigenic breast cells by fusing three independent methods. The general SGPL1 downregulation and the loss of the plasma membrane expression resulted in S1P dependent stimulation of migration in the breast cancer cell lines MCF-7 and BT-20. Not only S1P stimulated migration could be repressed by overexpressing the natural SGPL1 variant not but also more general migratory activity was significantly reduced. Here, for the first time, we report on the SGPL1 plasma membrane location in human, non-malignant breast epithelial cell lines silencing the extracellular S1P siren in vitro, and thereby regulating pivotal cellular functions. Loss of this plasma membrane distribution as well as low SGPL1 expression levels could be a potential prognostic marker and a viable target for therapy. Therefore, the precise role of SGPL1 for cancer treatment should be evaluated.

Adipokine RBP4 drives ovarian cancer cell migration

BackgroundObesity has been linked to several types of cancers including ovarian cancer. Retinol binding protein 4 (RBP4) is an adipokine that drives the development of hyperinsulinemia and type II diabetes in obesity patients and animals. Previously, we have identified RBP4 as a serum marker for ovarian cancer. Here we further explored the consequence of RBP4 upregulation in ovarian cancer cells and its molecular mechanism.ResultsOur results show that RBP4 is overexpressed in ovarian cancer cells to the same extent as in adipose tissues. The overexpression of RBP4 in ovarian cancer cells promotes cancer cell migration and proliferation. At molecular level, cancer progression factors MMP2 and MMP9 are induced in response to RBP4 overexpression. We further investigated which signaling pathways are utilized by RBP4 to activate ovarian cancer cell migration. We found RhoA/Rock1 pathway is turned on and CyclinD1 is upregulated in RBP4 overexpressed cells. Inhibition of RhoA/Rock1 pathway reduces the RBP4-induced MMP2 and MMP9 expression. The RBP4 action is depend on its associated ligand vitamin A/retinol acid (RA) and possibly involves similar pathways as for conferring insulin resistance. Moreover, we show that knockdown of RBP4 significantly reduce cancer cell migration and proliferation as well as expressions of oncogenic factors.ConclusionsOur results indicated that RBP4 can drive ovarian cancer cell migration and proliferation via RhoA/Rock1 and ERK pathway. It suggests that RBP4 act as a oncogene in ovarian cancer cells. Thus, RBP4 could be a molecular bridge between obesity and cancers and a potential target for treating obese cancer patients.

Proteomic profiling of human cancer pseudopodia for the identification of anti-metastatic drug candidates

Cancer metastasis causes approximately 90% of all cancer-related death and independent of the advancement of cancer therapy, a majority of late stage patients suffers from metastatic cancer. Metastasis implies cancer cell migration and invasion throughout the body. Migration requires the formation of pseudopodia in the direction of movement, but a detailed understanding of this process and accordingly strategies of prevention remain elusive. Here, we use quantitative proteomic profiling of human cancer pseudopodia to examine this mechanisms essential to metastasis formation, and identify potential candidates for pharmacological interference with the process. We demonstrate that Prohibitins (PHBs) are significantly enriched in the pseudopodia fraction derived from cancer cells, and knockdown of PHBs, as well as their chemical inhibition through Rocaglamide (Roc-A), efficiently reduces cancer cell migration.

Cellular localization and biological effects of 20nm-gold nanoparticles.

Gold nanoparticles (AuNPs) have recently emerged as prominent vehicles for many biomedical applications from sensing to delivery. The relevant literature contains conflicting data about the effects of AuNPs on living cells. The aim of present study is the synthesis and characterization of AuNPs at nanoscale, tracking their cellular localization and determining their effects on cell viability, migration and angiogenesis. Within this scope, 20 nm AuNPs were synthesized and characterized using various spectrometric techniques to determine their size, shape and surface properties such as charge and texture. Two main cell types including mouse fibroblast (L929) and human cervix adenocarcinoma (HeLa) were used in the study to compare the biological effects of colloidal gold on both non-cancer and cancer cells. AuNPs were allowed to interact with HeLa cells to determine their intracellular localization. AuNPs were mainly attached to the cell membrane/membranous compartments and to be captured in small amounts in cytoplasmic vacuoles or to be distributed freely in the cytosol. Scratch assay results showed that AuNPs reduced cancer cell migration especially at increasing concentrations. According to the chick chorioallantoic membrane assay, AuNPs exhibited strong anti-angiogenetic properties and can inhibit vascularization during angiogenesis. In addition, the MTT assay confirmed that AuNP-treated cells caused concentration dependent cytotoxic effects on both cell types. As a result, AuNPs not only have inhibitory effects on cancer cells, but also possess antiangiogenic activity, thus making them a multipotent agent for cancer therapy. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1708-1721, 2018.

Integrated analyses of multi-omics reveal global patterns of methylation and hydroxymethylation and screen the tumor suppressive roles of HADHB in colorectal cancer

BackgroundDNA methylation is an important epigenetic modification, associated with gene expression. 5-Methylcytosine and 5-hydroxymethylcytosine are two epigenetic hallmarks that maintain the equilibrium of epigenetic reprogramming. Disequilibrium in genomic methylation leads to carcinogenesis. The purpose of this study was to elucidate the epigenetic mechanisms of DNA methylation and hydroxymethylation in the carcinogenesis of colorectal cancer.MethodsGenome-wide patterns of DNA methylation and hydroxymethylation in six paired colorectal tumor tissues and corresponding normal tissues were determined using immunoprecipitation and sequencing. Transcriptional expression was determined by RNA sequencing (RNA-Seq). Groupwise differential methylation regions (DMR), differential hydroxymethylation regions (DhMR), and differentially expressed gene (DEG) regions were identified. Epigenetic biomarkers were screened by integrating DMR, DhMR, and DEGs and confirmed using functional analysis.ResultsWe identified a genome-wide distinct hydroxymethylation pattern that could be used as an epigenetic biomarker for clearly differentiating colorectal tumor tissues from normal tissues. We identified 59,249 DMRs, 187,172 DhMRs, and 948 DEGs by comparing between tumors and normal tissues. After cross-matching genes containing DMRs or DhMRs with DEGs, we screened seven genes that were aberrantly regulated by DNA methylation in tumors. Furthermore, hypermethylation of the HADHB gene was persistently found to be correlated with downregulation of its transcription in colorectal cancer (CRC). These findings were confirmed in other patients of colorectal cancer. Tumor functional analysis indicated that HADHB reduced cancer cell migration and invasiveness. These findings suggested its possible role as a tumor suppressor gene (TSG).ConclusionThis study reveals the global patterns of methylation and hydroxymethylation in CRC. Several CRC-associated genes were screened with multi-omic analysis. Aberrant methylation and hydroxymethylation were found to be in the carcinogenesis of CRC.