Low Metastatic Cells Research Articles

Proteomic analyses reveal divergent ubiquitylation patterns in hepatocellula carcinoma cell lines with different metastasis potential

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours, metastasis and recurrence remain the primary reasons for poor prognosis. Ubiquitination serves as a degradation mechanism of proteins, but it is involved in additional cellular processes including metastasis. Here, by using label-free quantification, double-glycine (di-Gly) antibody affinity purification and high-resolution liquid chromatography tandem mass spectrometry (LC-MS/MS), we investigated quantitative proteome, ubiquitylome, and the crosstalk between the two datasets in HCC cell lines with different metastasis potential to identify biomarkers associated with HCC metastasis. In total, 83 ubiquitinated proteins significantly and steadily changed their abundance according to their metastatic potential, and the participated biological processes of these ubiquitinated proteins were tightly associated with tumour metastasis. Further signaling pathway analysis revealed that the ribosome and proteasome were significantly over-activated in the highly metastatic cells. Furthermore, we analyzed the crosstalk between the whole proteome and the ubiquitylome, and further discussed the mechanism that how ubiquitination events affect HCC metastasis. Eventually, the ubiquitination of Ku80 was validated to be significantly down-regulated in the high-metastatic cells comparing with the low-metastatic cells. We believe that these findings will help us better understand the underlying molecular mechanisms of the metastasis of HCC. SignificanceIn this manuscript, we used label free based proteomics combined with diglycine antibody (di-Gly) affinity purification approach to identify biomarkers associated with HCC recurrence/metastasis in in a serial HCC cell lines with increasing invasion and metastasis potential. And then, we analyzed the crosstalk between the whole proteome and the ubiquitylome. Eventually, the ubiquitination of Ku80 was confirm to be closely associated with invasion and migration of HCC cells. As far as we know, this is the first time to use quantitative proteomic approach to study the ubiquitylomics in HCC cell lines with increasing metastasis ability.

Effects of orthotopic implantation of rat prostate tumour cells upon components of the N-acylethanolamine and monoacylglycerol signalling systems: an mRNA study

There is good evidence that the N-acylethanolamine (NAE)/monoacylglycerol (MAG) signalling systems are involved in the pathogenesis of cancer. However, it is not known how prostate tumours affect these systems in the surrounding non-malignant tissue and vice versa. In the present study we have investigated at the mRNA level 11 components of these systems (three coding for anabolic enzymes, two for NAE/MAG targets and six coding for catabolic enzymes) in rat prostate tissue following orthotopic injection of low metastatic AT1 cells and high metastatic MLL cells. The MLL tumours expressed higher levels of Napepld, coding for a key enzyme in NAE synthesis, and lower levels of Naaa, coding for the NAE hydrolytic enzyme N-acylethanolamine acid amide hydrolase than the AT1 tumours. mRNA levels of the components of the NAE/MAG signalling systems studied in the tissue surrounding the tumours were not overtly affected by the tumours. AT1 cells in culture expressed Faah, coding for the NAE hydrolytic enzyme fatty acid amide hydrolase, at much lower levels than Naaa. However, the ability of the intact cells to hydrolyse the NAE arachidonoylethanolamide (anandamide) was inhibited by an inhibitor of FAAH, but not of NAAA. Treatment of the AT1 cells with interleukin-6, a cytokine known to be involved in the pathogenesis of prostate cancer, did not affect the expression of the components of the NAE/MAG system studied. It is thus concluded that in the model system studied, the tumours show different expressions of mRNA coding for key the components of the NAE/MAG system compared to the host tissue, but that these changes are not accompanied by alterations in the non-malignant tissue.

Cytotoxic Effects of Plant Sap-Derived Extracellular Vesicles on Various Tumor Cell Types.

Edible plants have been widely used in traditional therapeutics because of the biological activities of their natural ingredients, including anticancer, antioxidant, and anti-inflammatory properties. Plant sap contains such medicinal substances and their secondary metabolites provide unique chemical structures that contribute to their therapeutic efficacy. Plant extracts are known to contain a variety of extracellular vesicles (EVs) but the effects of such EVs on various cancers have not been investigated. Here, we extracted EVs from four plants—Dendropanax morbifera, Pinus densiflora, Thuja occidentalis, and Chamaecyparis obtusa—that are known to have cytotoxic effects. We evaluated the cytotoxic effects of these EVs by assessing their ability to selectively reduce the viability of various tumor cell types compared with normal cells and low metastatic cells. EVs from D. morbifera and P. densiflora sap showed strong cytotoxic effects on tumor cells, whereas those from T. occidentalis and C. obtusa had no significant effect on any tumor cell types. We also identified synergistic effect of EVs from D. morbifera and P. densiflora saps on breast and skin tumor cells and established optimized treatment concentrations. Our findings suggest these EVs from plant sap as new candidates for cancer treatment.

Hyaluronic Acid Receptor‐RHAMM Mediates Renal Carcinoma Metastasis

The surface proteoglycan/glycoprotein layer (glycocalyx) on tumor cells has been associated with cellular functions that can potentially enable invasion and metastasis. In addition, aggressive renal carcinoma cells (SN12L1) with high metastatic potential have enhanced invasion rates compared to low metastatic (SN12C) cells in response to interstitial flow stimuli in vitro. Our previous studies suggest that heparan sulfate (HS) and hyaluronic acid (HA) in the glycocalyx play important roles in this flow mediated mechanotransduction and upregulation of invasive and metastatic potential. We examined HA receptor‐RHAMM protein levels in both SN12L1 and SN12C cell lines. We observed significantly higher RHAMM levels, but not CD44 levels, in flow dependent SN12L1 cells compared to SN12C cells suggesting that RHAMM may be transmitting the mechanical signal from hyaluronic acid to the cell. To examine this, we knocked down the expression of RHAMM by siRNA in SN12L1 cells. RHAMM knock‐down cells displayed suppression of flow induced migration suggesting that RHAMM receptor transmits the flow signal to the cell. SAHA (Suberoylanilide Hydroxamic Acid) is a small molecule drug (Vorinostat) that, in addition to functioning as an HDAC inhibitor, has been reported to inhibit the HS synthetic enzyme NDST1. We have previously demonstrated that NDST1 knockdown in highly metastatic SN12L1 cells blocked flow‐induced migration in vitro and reduced metastasis from the kidney by 95% in a mouse model [1]. We conducted flow induced migration assays in highly metastatic SN12L1 cells in the presence of 1.0 uM SAHA. SN12L1 cells treated with 1.0 uM SAHA displayed suppression of flow induced migration consistent with previous results showing NDST1 knockdown in highly metastatic SN12L1 cells blocked flow induced migration in vitro. We also examined the effect of flow on the glycocalyx and found that SN12L1 cells exposed to 24 hours of flow increased their HS expression by 3‐fold compared to static control. We have previously shown that flow sensed by HS is transmitted to the cell by glypican‐1 [2]. All of our data are consistent with the hypothesis that RHAMM is transmitting the mechanical signal from hyaluronic acid to the cell and HS is a flow sensor linked to glypican‐1.Support or Funding InformationFunding informationGrant: RO1CA204949 Targeting glycocalyx mediated mechanisms of tumor metastasis

Lipidomic Analysis of Cells and Extracellular Vesicles from High- and Low-Metastatic Triple-Negative Breast Cancer.

Extracellular vesicles (EVs) are lipid bilayer nanovesicles secreted from almost all cells including cancer. Cancer-derived EVs contribute to cancer progression and malignancy via educating the surrounding normal cells. In breast cancer, epidemiological and experimental observations indicated that lipids are associated with cancer malignancy. However, lipid compositions of breast cancer EVs and their contributions to cancer progression are unexplored. In this study, we performed a widely targeted quantitative lipidomic analysis in cells and EVs derived from high- and low-metastatic triple-negative breast cancer cell lines, using supercritical fluid chromatography fast-scanning triple-quadrupole mass spectrometry. We demonstrated the differential lipid compositions between EVs and cells of their origin, and between high- and low-metastatic cell lines. Further, we demonstrated EVs from highly metastatic breast cancer accumulated unsaturated diacylglycerols (DGs) compared with EVs from lower-metastatic cells, without increasing the amount in cells. The EVs enriched with DGs could activate the protein kinase D signaling pathway in endothelial cells, which can lead to stimulated angiogenesis. Our results indicate that lipids are selectively loaded into breast cancer EVs to support tumor progression.

Determination of cancer progression in breast cells by fiber optic bioimpedance spectroscopy system

Aim: It is well established that cancer can be most effectively treated when diagnosed at an early stage. Therefore, development, evaluation, and validation of new biomedical approaches for early detection of cancer and precancerous lesions are important priorities. Our aim was to distinguish low metastatic human breast cells from normal human breast cells using the Fiber Optic Bioimpedance Spectroscopy (FOBIS) system.Methods: In the FOBIS system we developed, the diameters of the fibers and platinum wires are 50 and 25µm, respectively. The sensitivity of the system to differentiate different cell types was assessed with high metastatic (MDA-MB-231), low metastatic (MCF-7) and normal breast epithelial cells (MCF-10A). Statistical evaluation of data was performed by using Principle Component Analysis (PCA) and Linear Discriminant Analysis (LDA). Spectroscopic data obtained from FOBIS system on suspended human breast cells were evaluated by multivariate statistical analysis to obtain information about the cell type. Fiber optic and bioimpedance methods allow discrimination of different cell types based on their signature. By combining these two techniques, the sensitivity of the system to the differentiation of human breast cells was evaluated.Results: The discrimination provided the sensitivity of 100% and specificity of 60% in distinguishing MCF-7 from MCF-10A cells.Conclusion: A highly accurate distinction of breast cancer cells was achieved in cell culture by FOBIS system.

Role of fucosyltransferase IV in the migration and invasion of human melanoma cells.

Malignant melanoma is one of the most aggressive human tumor types, mainly due to its high invasion capability, metastatic properties, and the absence of effective treatments. Glycosylation serves a pivotal role in the migration and invasion of melanoma. However, differences in glycosylation between high and low metastatic melanoma cells and how these regulate migration and invasion by altering the expression of fucosyltransferases (FUTs) remain unclear. In the present study, matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) analysis revealed that the composition profiling of fucosylated N-glycans differed between high metastatic C8161 and low metastatic A375P cells. Further analysis revealed that FUT4 expression was significantly increased in C8161 cells. Melanoma tissue arrays further demonstrated that FUT4 was overexpressed in metastatic samples. Altered FUT4 expression was accompanied by a change in the migration and invasion capacity of the cells. In addition, the migration and invasion potential of melanoma cells were decreased in C8161 and increased in A375P cells upon altering FUT4 expression levels by small interfering RNA or complementary DNA transfection. Furthermore, regulating FUT4 expression markedly modulated the activity of the phosphoinositide-3-kinase/Akt (PI3K/Akt) signaling pathway, which affected melanoma cell migration and invasion. In conclusion, FUT4 is a novel biomarker and regulator of the migration and invasion of melanoma cells and may serve as a therapeutic target for melanoma.

Low ALK FISH positive metastatic non-small cell lung cancer (NSCLC) patients have shorter progression-free survival after treatment with ALK inhibitors

ALK FISH assay guides clinical decision to initiate therapy with ALK inhibitors in patients with stage IV non-small cells lung cancer (NSCLC). In this single institution retrospective study, we investigated the association between the strength of ALK positivity and progression-free survival (PFS) We screened 4,829 patients tested for ALK rearrangement by FISH from 01/06/2012 to 06/30/2018 and included 66 stage IV NSCLC ALK positive patients, who were ALK inhibitor naïve, received an ALK inhibitor, and been followed at least 10 months to the study. The median PFS for cases high positive cases [≥=50% positive nuclei; n = 49] and low positive cases [16–49% positive nuclei; n = 17] is 16 months and 4 months respectively, and the hazard ratio is 2.89 [95 CI 1.34–6.2] (p = 0.0068). When cases are stratified according to cut-off ≥=30% positive nuclei, the median PFS for cases above (n = 55) and below the cut-off (n = 11) is 12 and 3 months, respectively and the hazard ratio is 9.60 [95 CI 2.63–35.04] (p < 0.0001) Patients with low FISH positive results have shorter PFS. Although a biological reason is plausible, false positivity may be a contributing factor. For low positive results, confirmation of the FISH result with an orthogonal technology is warranted.

The cancer cell glycocalyx proteoglycan Glypican-1 mediates interstitial flow mechanotransduction to enhance cell migration and metastasis.

Previous studies have demonstrated that the glycosaminoglycans (GAGs) heparan sulfate (HS) and hyaluronic acid (HA) are mechanosensors for interstitial flow on cancer cells. The proteins that link the GAGs to the cancer cell for mechanotransduction, however, are not known. To assess whether the HS proteoglycan core proteins, Glypican-1 and Syndecan-1, or the HA receptor, CD44, provides the mechanical linkage to the cell. The highly metastatic renal carcinoma cell line (SN12L1) and its companion low metastatic cell line (SN12C) were analyzed by Western blot, siRNA, and a 3-dimensional interstitial flow migration assay. There was significant elevation of Glypican-1 protein expression in the SN12L1 cells relative to the SN12C cells while there were no significant differences in Syndecan-1 or CD44. Knock down of Glypican-1 by siRNA completely blocked flow induced migration in SN12L1 cells. MAPK inhibitors also blocked flow induced migration in SN12L1 cells. Glypican-1 provides the mechanical linkage from HS (the flow sensor) to the SN12L1 cell where mechanotransduction leading to the enhancement of migration (metastasis) occurs. MAPKs downstream of Glypican-1 propagate the signal. The HS, Glypican-1, MAPK signaling axis suggests opportunities for pharmaceutical intervention.

Interleukin-8 promotes integrin \u03b23 upregulation and cell invasion through PI3K/Akt pathway in hepatocellular carcinoma

BackgroundInterleukin-8 (IL-8) plays a vital role in the invasion and metastasis of hepatocellular carcinoma (HCC), and is closely associated with poor prognosis of HCC patients. Integrin αvβ3, a member of the integrin family, has been reported to be overexpressed in cancer tissues and mediate the invasion and metastasis of HCC cells. However, the relationship between IL-8 and integrin αvβ3 in HCC and the underlying mechanism of IL-8 and integrin αvβ3 in the invasion of HCC remains unclear.MethodsThe expression of IL-8, integrin αv and integrin β3 in HCC cells and tissues was detected by quantitative real-time PCR, Western blot and immunohistochemistry. Transwell assay and Western blot was used to detect the invasiveness, the expression of integrin β3 and the activation of PI3K/Akt pathway of HCC cells pretreated with IL-8 knockdown or exogenous IL-8.ResultsIL-8, integrin αv and integrin β3 were overexpressed in highly metastatic HCC cell lines compared with low metastatic cell lines. There was a positive correlation between integrin β3 and IL-8 expression in HCC tissues. IL-8 siRNA transfection reduced HCC cell invasion and the levels of integrin β3, p-PI3K and p-Akt. IL-8 induced HCC cell invasion and integrin β3 expression was significantly inhibited by transfection with CXCR1 siRNA or CXCR2 siRNA. When we stimulated HCC cells with exogenous IL-8, cell invasion and the levels of integrin β3, p-PI3K, and p-Akt increased, which could be effectively reversed by adding PI3K inhibitor LY294002.ConclusionsOur results suggest that IL-8 promotes integrin β3 upregulation and the invasion of HCC cells through activation of the PI3K/Akt pathway. The IL-8/CXCR1/CXCR2/PI3K/Akt/integrin β3 axis may serve as a potential treatment target for patients with HCC.

Effects of periostin on hepatocellular carcinoma cells invasion, metastasis and prognosis

Objective: To investigate the prognostic relationship between the expression levels of periostin (POSTN) in hepatocellular carcinoma (HCC) tissues as well as its effect in invasion and metastasis. Methods: The expression levels of POSTN in liver cancer tissues were detected with real-time quantitative PCR (QPCR) and immunohistochemistry (IHC). Kaplan-Meier method and Log-rank test were used to analyze the relationship between POSTN expression level and postoperative prognosis in patients with liver cancer. The expression of POSTN in hepatocellular carcinoma cells with different metastasis characteristics were detected in vitro and the overexpression of POSTN in low metastatic hepatocellular carcinoma cells was mediated through plasmid transfection techniques. The effects of POSTN on invasion and metastasis of hepatocellular carcinoma cells were determined by transwell migration and matrigel invasion assay. The comparative expression level of POSTN was analyzed by t-test. Results: The expression levels of POSTN in tissues from high to low was in the order of metastatic liver cancer tissues, non-metastatic liver cancer tissues and normal liver tissues (P = 0.006). The median survival time and 3-year survival rate in postoperative patients with hepatocellular carcinoma of high POSTN expression level were significantly lower than the low expression group (10.00 months, 44.44%; 59.00 months, 53.13%, P = 0.031 2). In in vitro testing, the expression of POSTN was highest in MHCC97H cells with high metastatic characteristics as compared with Huh7 and MHCC97L cells with low and medium metastatic characteristics. After overexpression of POSTN in MHCC97L cells, the migration and invasion capacity of MHCC97L cells was increased. Conclusion: POSTN is associated with pathological processes such as metastasis and invasion of liver cancer, which may promote the migration and invasion of liver cancer cells. It is expected to be an important prognostic biomarker of tumor recurrence and a therapeutic target for inhibiting the occurrence of metastasis in postoperative patients with hepatocellular carcinoma.

The application of whole exome sequencing in different metastatic potential of heptaocellular carcinoma

Objective Genome-wide exome sequencing was used to analyze DNA of hepatocellular carcinoma (HCC) tissues and cell lines with different metastatic potentials to explore the mutation genes and sites related to the HCC metastasis. Methods Genomic DNA extracted from twelve HCC tumors and its adjacent tissues and six HCC cells (HCC-LM3, MHCC-97L, MHCC-97H, HepG2, SMCC-7721 and PLC-RFP-5) with different metastatic potentials were analyzed by whole exome sequencing. Bioinformatics analysis and screening of mutations was used to investigated mutation genes and sites potentially associated with HCC metastasis. Results Comparing high and low metastatic potential HCC, high metastatic potential HCC group had more than three gene mutations including UIMC1 (rs3733876 C/T), SEMA3C (rs1527482 G/A), SAMD9 (rs10279499 G/T), RECK (rs16932912 G/A), PDLIM4 (rs4877 G/T, LIMK2 (rs3747154 A/G), CRIM1 (rs3821169 G/T) which was associated with HCC metastasis. Mutate genes and its sites such as CAPZB (rs79308175C/T), CSF1R (rs10079250A/G), HSPA5 (rs143920039A/T), SORBS3 (rs2449331T/C, rs3758036C/T) only occured in high metastatic potential HCC cells (HCC-LM3, MHCC-97L and MHCC-97H), while mutation sites RASAL3 (rs146624357G/A, rs142945276 C/T) only appeared in three low metastatic potential cells (HepG2, SMCC-7721 and PLC-RFP-5). The DNA comparative analysis of three homologous high metastatic potential HCC cell lines (HCC-LM3, MHCC-97Land MHCC-97H) showed that only EHBP1 (rs77403174T/C) was presented in HCC-LM3, while FAM189B (rs150296362C/T), SERPINB13 (rs144903442G/A) and ARHGEF1 (rs2303797C/T) only presented in MHCC-97L and MHCC-97H. Conclusion Mutations and its sites such as UIMC1 (rs3733876C/T), SEMA3C (rs1527482G/A), SAMD9 (rs10279499G/T) was detected to potentially related to the HCC metastasis by genome-wide exome sequencing. Key words: Whole exome sequencing; Hepatocellular carcinoma; Mutations; Metastasis

MiR-199 inhibits EMT and invasion of hepatoma cells through inhibition of Snail expression.

MiR-199 expression is associated with liver cancer. Bioinformatics analysis revealed that miR-199 has a complementary binding site to the 3'-UTR region of Snail mRNA. This study investigated whether miR-199 plays a role in regulating Snail expression and affecting epithelial-mesenchymal transition (EMT) and invasion of hepatoma cells. The Dual-Luciferase reporter gene assay validated the targeted regulation between miR-199 and Snail. QRT-PCR was used to detect and compare the expression of miR-199 and Snail mRNA in human normal liver HL7702 cells, low metastatic MHCC97L cells, and high metastatic MHCC97H cells. MHCC97H cells were cultured in vitro and divided into two groups: miR-NC group and the miR-199 mimic group followed by the analysis of the expression of Snail, E-cadherin, and N-cadherin, as well as cell invasion ability by transwell assay. There was a targeted regulatory relationship between miR-199 and Snail mRNA. Compared with HL7702 cells, miR-199 expression was significantly decreased, and Snail expression was significantly increased in MHCC97L and MHCC97H cells, with more changes being observed in high metastatic MHCC97H cells. The transfection of miR-199 mimic significantly downregulated the expression of Snail and N-cadherin in MHCC97H cells, increased E-cadherin expression, inhibited the cell's EMT process, and invasion. The decrease of miR-199 expression plays a role in upregulating the expression of Snail and promoting EMT and invasion of hepatocarcinoma cells. The increase of the expression of miR-199 can inhibit the expression of Snail and inhibit the EMT process and invasion ability of hepatoma cells.

Mining featured biomarkers associated with vascular invasion in HCC by bioinformatics analysis with TCGA RNA sequencing data

This study aims to identify the feature genes associated with vascular invasion in hepatocellular carcinoma (HCC). Here, the RNA sequencing data related to vascular invasion in The Cancer Genome Atlas (TCGA) database, including 292 HCC patients with complete clinical data were included in our study as the training dataset for construction and E-TABM-36, including 41 HCC patients with complete clinical data was used as the validation dataset. Following data normalization, differentially expressed mRNA and copy number (CN) were selected between with and without vascular invasion samples. A support vector machine (SVM) classifier was constructed and validated in GSE9828 and GSE20017 datasets. Total 59 feature genes were found by the SVM classifier. Using Cox regression analysis, three clinical features, including Patholigic T, Stage and vascular invasion and 6 optimal prognostic genes, including ANO1, EPHX2, GFRA1, OLFM2, SERPINA10 and TKT were significantly correlated with prognosis. A risk score formula was developed to assess the prognostic value of 6 optimal prognostic genes, which were identified to possess the most remarkable correlation with overall survival in HCC patients. By performing in vitro experiments, we observed TKT was significantly increased, but OLFM2 was decreased in high metastatic potential HCC cell lines (SK-HEP-1 and MHCC-97 H) compared with low metastatic potential cell line Huh7 and normal human liver cell line LO2 using western blotting analysis. Knockdown of TKT in MHCC-97H or overexpression of OLFM2 in SK-HEP-1 significantly suppressed cell migration and invasion using transwell assays. Our results demonstrated that TKT and OLFM2 might be novel independent biomarkers for predicting survival based on the presence of vascular invasion in patients with HCC.

Quantitative Measurements of Intercellular Adhesion Strengths between Cancer Cells with Different Malignancies Using Atomic Force Microscopy.

Intercellular adhesion strengths between two kinds of murine breast cancer cells with different malignancies were measured quantitatively using a metal cup-attached chip with atomic force microscopy (AFM). The cup-attached chip was used to approach a cell, pick it up, and then approach another cell, and the adhesion strengths were measured according to the contact time of the cells between 0 to 60 s. Separation work was used as a parameter for quantitative comparisons of the strengths. As a result, the work of a highly metastatic cancer cell (FP10SC2) was greater than a low metastatic cancer cell (4T1-LM) throughout all contact times examined. Adhesion was analyzed from a point of a view of binding kinetics of receptors on cells, and two possibilities were found: one was the number of cell adhesive receptors increased, and the other was the work to separate single molecular binding increased with increasing cancer cell malignancy. These results indicated quantitative measurements of intercellular adhesion strengths using AFM yielded information to understand the mechanism of the cancer progression from a new perspective.

Identification of reciprocal microRNA-mRNA pairs associated with metastatic potential disparities in human prostate cancer cells and signaling pathway analysis.

The major cause of mortality for prostate cancer (PCa) is metastasis; however, the metastatic mechanism remains unclear. MicroRNAs (miRNAs) alter the expression patterns of essential genes through posttranscriptional regulation during cancer development. The study was mainly aimed at identifying specific miRNA-messenger RNA (mRNA) interactions and signaling pathways associated with PCa distant metastasis. New analytical approaches were applied, combining miRNA and gene expression microarray, to screen differentially expressed miRNA-mRNA pairs in the normal prostate epithelial cell line RWPE-1, the highly-metastatic human PCa cell line PC-3M-1E8 (H-1E8 or 1E8) and the lowly metastatic cell line PC-3M-2B4 (L-2B4 or 2B4). Eight differentially expressed candidate miRNAs and their targets closely related to PCa metastasis were identified and validated in patients by using the Gene Expression Omnibus database. Among them, overexpression of hsa-miR-92b-3p and hsa-let-7a-5p and underexpression of their targets, such as glutathione-S-transferase M3 (GSTM3), baculoviral IAP repeat-containing 3, and cyclin-dependent kinase inhibitor 1 (CDKN1A), were also validated in H-1E8 cells compared with L-2B4 cells. Bioinformatics suggested that hsa-miR-92b-3p and hsa-let-7a-5p and their targets might promote PCa metastasis through platinum-based drug resistance and the JAK-STAT signaling pathway. H-1E8 and L-2B4 cells treated by cisplatin showed the greatly decreased levels of hsa-miR-92b-3p and hsa-let-7a-5p; however, in contrast to 2B4 cells, 1E8 cells did not negatively regulate the increase in the expression levels of the targets GSTM3 and CDKN1A. This finding suggests that the dysregulation between hsa-let-7a-5p/CDKN1A and hsa-miR-92b-3p/GSTM3 pairs is associated with platinum-based chemoresistance of metastatic cancer cells.

ANXA2Tyr23 and FLNASer2152 phosphorylation associate with poor prognosis in hepatic carcinoma revealed by quantitative phosphoproteomics analysis

Hepatoma is one of the most common malignant tumors, and most patients have very poor prognosis. Early prediction and intervention of the hepatoma recurrence/metastasis are the most effective way to improve the patients' clinical outcomes. Here, we used isobaric tags for relative and absolute quantitation (iTRAQ) based quantitative phospho-proteomics approach to identify biomarkers associated with hepatoma recurrence/metastasis in hepatoma cell lines with increasing metastasis ability. In total, 75 phosphorylated peptides corresponding to 60 phosphoproteins were significantly dysregulated and the participated biological processes of these phosphoproteins were tightly associated with tumor metastasis. Further signaling pathway analysis revealed that key signaling pathways which play crucial roles in cancer metastasis have been significantly over activated in the highly metastatic cells. Furthermore, the phosphorylation of FLNASer2152 and ANXA2Tyr23 were validated to be significantly up regulated in the high-metastatic cells comparing with the low-metastatic cells. By further investigation the clinical significance of the phosphorylation of FLNASer2152 and ANXA2Tyr23 in large-scale clinical samples, revealed that the over phosphorylation of FLNASer2152 and ANXA2Tyr23 were associated with poor prognosis and might be potential prognostic biomarkers for the primary hepatoma. When FLNASer2152 combined with ANXA2Tyr23, it had a better prognostic value for both OS and TTR.

The relationship between metastatic potential and in vitro mechanical properties of osteosarcoma cells.

Osteosarcoma is the most frequent primary tumor of bone and is characterized by its high tendency to metastasize in lungs. Although treatment in cases of early diagnosis results in a 5-yr survival rate of nearly 60%, the prognosis for patients with secondary lesions at diagnosis is poor, and their 5-yr survival rate remains below 30%. In the present work, we have used a number of analytical methods to investigate the impact of increased metastatic potential on the biophysical properties and force generation of osteosarcoma cells. With that aim, we used two paired osteosarcoma cell lines, with each one comprising a parental line with low metastatic potential and its experimentally selected, highly metastatic form. Mechanical characterization was performed by means of atomic force microscopy, tensile biaxial deformation, and real-time deformability, and cell traction was measured using two-dimensional and micropost-based traction force microscopy. Our results reveal that the low metastatic osteosarcoma cells display larger spreading sizes and generate higher forces than the experimentally selected, highly malignant variants. In turn, the outcome of cell stiffness measurements strongly depends on the method used and the state of the probed cell, indicating that only a set of phenotyping methods provides the full picture of cell mechanics.

HACE1 is a potential tumor suppressor in osteosarcoma

Osteosarcoma is a malignant bone sarcoma characterized by extensive genomic disruption and a propensity for metastatic spread. Osteoid production suggests a close relationship with normal osteoblasts, and the latter are the presumptive cell of origin of this disease. The HACE1 gene, localized to human chromosome 6q21, encodes the HACE1 HECT E3 ligase, a tumor suppressor in diverse tumors that acts in part by targeting the activated form of RAC1 GTPase for proteasomal degradation. Disruption or loss of 6q21 is relatively common in osteosarcomas, and Hace1−/−/Tp53+/− mice frequently develop osteosarcomas, in contrast to Tp53+/− mice, which do not. This suggests an unexplored link between HACE1 loss and osteosarcoma. Here we compared HACE1 expression in normal osteoblasts and osteosarcoma cell lines in vitro by western blotting and quantitative RT-PCR, and in human osteosarcoma specimens by immunohistochemistry. Both HACE1 transcript and protein levels were reduced in osteosarcoma compared to osteoblasts in vitro. Reduced HACE1 expression in osteosarcoma tumors was observed in 76% of cases and associated with high-grade lesions. Further, clonally derived pairs of high and low metastatic osteosarcoma cell lines showed significant downregulation in the high compared to corresponding low metastatic cells. Ectopic expression of HACE1 markedly inhibited anchorage-independent growth and cell motility of HACE1 osteosarcoma cell lines, and was associated with reduced RAC1 activation and decreased reactive oxygen species (ROS). Finally, HACE1 overexpression blocked osteosarcoma xenograft growth and dramatically reduced pulmonary metastases. These findings point to a potential tumor suppressor function for HACE1 in osteosarcoma.

Ecto-5'-nucleotidase (CD73) is a potential target of hepatocellular carcinoma.

High expression of ecto-5'-nucleotidase (CD73) has been reported in a number of epithelium origin malignancies. Here, we hypothesize that CD73 promotes hepatocellular carcinoma (HCC) growth and metastasis and that the effect is mediated by epithelial growth factor receptor (EGFR). HCC cells with different malignancies and Tissue microarrays of the tumor and peritumoral liver tissues from 30 independent patients were used to examine CD73 and EGFR expression. Then, MTT and Ki67 detection, together with cell adhesion, invasion, and migration assays were used to evaluate the effects of CD73 on cell growth and metastasis. The expression of EGFR in HCC cells was also tested after suppressing or overexpressing CD73. Lastly, tumor tissues from nude mice, which had been injected subcutaneously with HCC cells, were transplanted subcutaneously into CD73-/- and wild-type (WT) C57 mice. CD73 expression was higher in HCC cells with greater metastatic potentials and tumor tissues compared with low metastatic cells and peritumor tissues. CD73 and EGFR were coexpressed and positively correlated in tumor and peritumor liver tissues in HCC tissue microarrays. Up-regulationof CD73 by plasmid transfection or by pharmacological agents promoted EGFR expression in HCC cells, whereas suppression of CD73 inhibited these effects. The growth of transplanted tumor tissues was dramatically slower in CD73-/- mice than in WT type mice in the in vivo experiments. CD73 promotes HCC growth and metastasis and upregulated the expression of EGFR in HCC. Thus, CD73 and EGFR are potential targets in the treatment of HCC.