Glucose regulated protein 78 (GRP78) inhibits apoptosis and attentinutes chemosensitivity of gemcitabine in breast cancer cell via AKT/mitochondrial apoptotic pathway.

The underlying mechanism of gemcitabine resistance during breast cancer treatment remains unclear. Glucose regulated protein 78 (GRP78) frequently triggered by anticancer agents, was substantially elevated in gemcitabine resistant sublines. Ectopic expression of GRP78 changes gemcitabine chemosensitivity and apoptosis levels in breast cancer cells. Further experiments showed an involvement of caspase 9, not caspase 8, in gemcitabine resistance and GRP78-mediated chemosensitivity, suggesting that mitochondria apoptotic pathway was activated by GRP78. This finding was further supported by the observations of AKT activation, Bcl-2 increase, Bax and Bim decrease. Conclusively, GRP78 plays a vital role in gemcitabine resistance and clinical strategy to improve gemcitabine efficacy in breast cancer by manipulating GRP78 should be explored.

MiRNA-21 induces epithelial to mesenchymal transition and gemcitabine resistance via the PTEN/AKT pathway in breast cancer.

Acquisition of gemcitabine resistance in breast cancer has not been fully clarified. Prior studies suggest that miRNAs are important to chemoresistance in solid tumors and we confirmed that miR-21 is involved in the development of gemcitabine resistance. Epithelial-to-mesenchymal transition (EMT) and AKT pathway activation were noted to be important to this resistance as well. PTEN, a direct target gene of miR-21, was significantly downregulated in gemcitabine-resistant breast cancer cells and restoration of PTEN expression blocked miR-21-induced EMT and gemcitabine resistance. Our data offer novel insight into gemcitabine resistance in breast cancer and suggest that miR-21 may be used to predict optimal breast cancer therapy and may be a potential therapeutic target for reversing gemcitabine resistance.

MiR-612 suppresses the stemness of liver cancer via Wnt/ß-catenin signaling.

Previous research showed that microRNA-612 (miR-612) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of hepatocellular carcinoma (HCC). AKT2 was confirmed to be a direct target of miR-612, through which the epithelial-mesenchymal transition (EMT) and metastasis of HCC were inhibited. Our present findings reveal that miR-612 is able to suppress the stemness of HCC by reducing the number and size of tumorspheres as well as clone formation in soft agar, and to relieve drug resistance to cisplatin and 5-fluorouracil. In addition, miR-612 hampered the capacity of tumorigenesis in NOD/SCID mice and redistributed the tumor invasive frontier of miR-612-modulating cells. Finally, our findings suggest that Wnt/ß-catenin signaling is required in the regulation of EMT-associated stem cell-like traits by miR-612.

MiR-146a enhances angiogenic activity of endothelial cells in hepatocellular carcinoma by promoting PDGFRA expression.

Endothelial cells (ECs) are critical for angiogenesis, and microRNAs play important roles in this process. We investigated the regulatory role of microRNAs in ECs of hepatocellular carcinoma (HCC) by examining the microRNA expression profile of human umbilical vein endothelial cells (HUVECs) in the absence or presence of human HCC cells, and identified miR-146a as the most highly upregulated microRNA. Furthermore, we revealed that miR-146a promoted the expression of platelet-derived growth factor receptor α (PDGFRA) in HUVECs, and this process was mediated by BRCA1. Overexpression of PDGFRA in the ECs of HCC tissues was associated with microvascular invasion and predicted a poorer prognosis. These results suggest that miR-146a plays a key role in regulating the angiogenic activity of ECs in HCC through miR-146a-BRCA1-PDGFRA pathway. MiR-146a and PDGFRA may emerge as potential anti-angiogenic targets on ECs for HCC therapy.

Low level of ARID1A contributes to adaptive immune resistance and sensitizes triple-negative breast cancer to immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) shed new light on triple-negative breast cancer (TNBC), but only a minority of patients demonstrate response. Therefore, adaptive immune resistance (AIR) needs to be further defined to guide the development of ICI regimens. METHODS: Databases, including The Cancer Genome Atlas, Gene Ontology Resource, University of California Santa Cruz Genome Browser, and Pubmed, were used to screen epigenetic modulators, regulators for CD8+ T cells, and transcriptional regulators of programmed cell death-ligand 1 (PD-L1). Human peripheral blood mononuclear cell (Hu-PBMC) reconstruction mice were adopted for xenograft transplantation. Tumor specimens from a TNBC cohort and the clinical trial CTR20191353 were retrospectively analyzed. RNA-sequencing, Western blotting, qPCR and immunohistochemistry were used to assess gene expression. Coculture assays were performed to evaluate the regulation of TNBC cells on T cells. Chromatin immunoprecipitation and transposase-accessible chromatin sequencing were used to determine chromatin-binding and accessibility. RESULTS: The epigenetic modulator AT-rich interaction domain 1A (ARID1A) gene demonstrated the highest expression association with AIR relative to other epigenetic modulators in TNBC patients. Low ARID1A expression in TNBC, causing an immunosuppressive microenvironment, promoted AIR and inhibited CD8+ T cell infiltration and activity through upregulating PD-L1. However, ARID1A did not directly regulate PD-L1 expression. We found that ARID1A directly bound the promoter of nucleophosmin 1 (NPM1) and that low ARID1A expression increased NPM1 chromatin accessibility as well as gene expression, further activating PD-L1 transcription. In Hu-PBMC mice, atezolizumab demonstrated the potential to reverse ARID1A deficiency-induced AIR in TNBC by reducing tumor malignancy and activating anti-tumor immunity. In CTR20191353, ARID1A-low patients derived more benefit from pucotenlimab compared to ARID1A-high patients. CONCLUSIONS: In AIR epigenetics, low ARID1A expression in TNBC contributed to AIR via the ARID1A/NPM1/PD-L1 axis, leading to poor outcome but sensitivity to ICI treatment.

Aryl hydrocarbon receptor nuclear translocator is associated with tumor growth and progression of hepatocellular carcinoma.

bHLH/PAS proteins play important roles in tumor progression. Lost or reduced expression of single-minded homolog 2 (SIM) as well as aryl hydrocarbon receptor repressor (AHRR) has been observed in cancerous human tissues. Here, we investigated the role of aryl hydrocarbon receptor nuclear translocator (ARNT), another bHLH/PAS protein, in hepatocellular carcinoma (HCC). Using tissue microarray and immunohistochemistry, we found that intratumoral ARNT was inversely correlated with time to recurrence and overall survival of HCC patients after resection. Knockdown of ARNT in HepG2, HCCLM3 and HCCLM6 cells significantly shortened cell doubling time, increased S-phase cell populations and accelerated in vivo HCCLM6 growth and metastasis. After ARNT expression was rescued, prolonged cell doubling time and decreased S-phase cell populations were observed in HepG2, HCCLM3 and HCCLM6 cells. And, HCCLM6 growth and metastasis in vivo were remarkably inhibited. Screening by quantitative reverse-transcription PCR and PCR arrays revealed that cyclin E1, CDK2, Fos and Jun were negatively regulated by ARNT, whereas CDKN1C, CNKN2A, CDKN2B, MAPK11 and MAPK14 were positively regulated in HCC. According to the results of immunoprecipitation assay, both ARNT/ARNT and ARNT/AHRR complexes were clearly formed in HCCLM6 xenograft with increased ARNT expression. In summary, ARNT is an important regulator of HCC growth and metastasis and could be a promising prognostic candidate in HCC patients.

HIWI is associated with prognosis in patients with hepatocellular carcinoma after curative resection.

BACKGROUND: PIWI protein family was found to play an important role in stem cell self-renewal. Overexpression of HIWI, the human homolog of PIWI family proteins, was found in several solid tumors, although the role of HIWI in hepatocellular carcinoma (HCC) and its prognostic value remain unclear. METHODS: HIWI expression was measured in stepwise metastatic HCC cell lines (HCCLM3, MHCC97H, MHCC97L, SMMC7721, and HepG2), the normal liver cell line (L02), and HCC tissue samples (n = 20). Proliferation and invasion were investigated in HCC cell lines undergoing HIWI target small interfering RNA transfection. Also explored was HIWI expression in HCC tissue microarrays (n = 168) for survival analysis. RESULTS: Levels of HIWI protein and mRNA were up-regulated in highly metastatic HCC cell lines (HCCLM3, MHCC97H, and MHCC97L), whereas their proliferation and invasion significantly decreased after depletion of HIWI. Intratumoral HIWI expression was higher than that of peritumoral tissue (P < .001) and positively associated with proliferating cell nuclear antigen expression (P < .001). Positive expression of intratumoral HIWI was associated with larger tumor size (P = .047) and intrahepatic metastasis (P = .027) and was an independent risk factor for overall survival (P = .007) and recurrence-free survival (P = .036), particularly in patients with low serum α-fetoprotein and low Edmondson-Steiner grade. CONCLUSIONS: HIWI may play a key role in HCC proliferation and metastasis and can be a potential prognostic factor for HCC after curative resection, particularly with well-differentiated HCC.

[A nude mouse model of hepatocellular carcinoma single cell-derived organ site-specific metastasis].

OBJECTIVE: To establish a single cell-derived organ site-specific metastatic model of human hepatocellular carcinoma (HCC) in the nude mouse. METHODS: Using the limited dilution method, HCCLM3-R-LM1 and HCCLM3-R-LnM1 cell lines were used to generate eight (LM1-S2, -S3, -S4, -S5, -S11, -S15, -S21, and -S23) and five (LnM1-S7, -S11, -S13, -S17, and -S20) single cell-derived monoclonal cell lines, respectively. The monoclonal cell lines were seeded into 4-week-old nude mice, and three weeks later the resultant subcutaneous tumor tissues were orthotopically transplanted into the livers of nude mice. At six weeks after implantation, lung and lymph node were extracted for analysis of the metastatic foci fluorescence area and pathology to assess the number of metastatic foci. RESULTS: Among the 13 mice implanted with the established monoclonal cell lines, six grew subcutaneous tumors. When orthotopically transplanted, the six tumors showed remarkably different metastatic potential and organ site-specific tropism. The fluorescence areas of lung metastatic foci were: LM1-S3, 80 923+/-10 162; LM1-S4, 1506 000+/-297 064; LM1-S5, 36 140+/-8 210; and LM1-S11, 508 448+/-134 272 (P less than 0.01); no lymph node metastases were found for these lines. For LnM1-S11, the fluorescence areas of lung and lymph node metastatic foci were 435 062+/-206 620 and 1 254 000+/-225 171, respectively. CONCLUSION: We successfully established several monoclonal cell lines and nude mouse models of HCC with different metastatic potential and organ tropism. Among them, LM1-S3, LM1-S4, LM1-S5, and LM1-S11 have metastasis organotropism to lung. The LnM1-S11 line exhibits dual metastasis organotropism to lung and lymph node. These monoclonal cell lines and nude mouse models may represent useful tools for study of HCC metastasis organotropism.

Apatinib plus vinorelbine versus vinorelbine for metastatic triple-negative breast cancer who failed first/second-line treatment: the NAN trial.

While therapies such as chemotherapy combined with immunotherapy, sacituzumab govitecan, and PARP inhibitors are available for metastatic TNBC, on disease progression after these therapies, the mainstay of therapy is chemotherapy. Apatinib is a small-molecule tyrosine kinase inhibitor that has promising anti-angiogenesis and antitumor activity for TNBC. We aimed to evaluate the safety and efficacy of adding apatinib to chemotherapy in patients with advanced TNBC with failed first/second-line treatment. A total of 66 patients were randomly assigned, in a 1:1 ratio, to receive vinorelbine or vinorelbine with apatinib in 28-day cycles. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), overall response rate (ORR) and safety. 33 received apatinib plus vinorelbine and 32 received vinorelbine (1 was withdrawal). Median PFS was significantly longer in the apatinib plus vinorelbine group than in the vinorelbine group (3.9 months vs. 2.0 months; hazard ratio, 1.82; 95% confidence interval [CI], 1.06 to 3.11; P = 0.026). Median OS was 11.5 months with apatinib plus vinorelbine and 9.9 months with vinorelbine (HR,1.01; 95% CI, 0.51 to 1.97; P = 0.985). The ORR was 9.1% in the apatinib plus vinorelbine group and 6.3% in the vinorelbine group (P = 0.667). The most common treatment-related hematologic grade 3-4 adverse events in apatinib plus vinorelbine group, were leukopenia, granulocytopenia, anemia, and thrombocytopenia. no treatment-related nonhematologic grade 4 adverse events or treatment-related deaths were observed. Collectively, adding apatinib to vinorelbine shows a promising benefit in PFS compared to vinorelbine monotherapy, with an excellent toxicity profile, warranting further exploration.

Isomalto oligosaccharide sulfate inhibits tumor growth and metastasis of hepatocellular carcinoma in nude mice.

BACKGROUND: Hepatocellular carcinoma (HCC) usually has a dismal prognosis because of its limited response to current pharmacotherapy and high metastatic rate. Sulfated oligosaccharide has been confirmed as having potent antitumor activities against solid tumors. Here, we explored the preclinical effects and molecular mechanisms of isomalto oligosaccharide sulfate (IMOS), another novel sulfated oligosaccharide, in HCC cell lines and a xenograft model. METHODS: The effects of IMOS on HCC proliferation, apoptosis, adhesion, migration, and invasiveness in vitro were assessed by cell counting, flow cytometry, adhesion, wound healing, and transwell assays, respectively. The roles of IMOS on HCC growth and metastasis in xenograft models were evaluated by tumor volumes and fluorescent signals. Total and phosphorylated protein levels of AKT, ERK, and JNK as well as total levels of c-MET were detected by Western blotting. IMOS-regulated genes were screened by quantitative reverse-transcription PCR (qRT-PCR) array in HCCLM3-red fluorescent protein (RFP) xenograft tissues and then confirmed by qRT-PCR in HepG2 and Hep3B cells. RESULTS: IMOS markedly inhibited cell proliferation and induced cell apoptosis of HCCLM3, HepG2, and Bel-7402 cells and also significantly suppressed cell adhesion, migration, and invasion of HCCLM3 in vitro. At doses of 60 and 90 mg/kg/d, IMOS displayed robust inhibitory effects on HCC growth and metastasis without obvious side effects in vivo. The levels of pERK, tERK, and pJNK as well as c-MET were significantly down-regulated after treatment with 16 mg/mL IMOS. No obvious changes were found in the levels of pAkt, tAkt, and tJNK. Ten differentially expressed genes were screened from HCCLM3-RFP xenograft tissues after treatment with IMOS at a dose of 90 mg/kg/d. Similar gene expression profiles were confirmed in HepG2 and Hep3B cells after treatment with 16 mg/mL IMOS. CONCLUSIONS: IMOS is a potential anti-HCC candidate through inhibition of ERK and JNK signaling independent of p53 and worth studying further in patients with HCC, especially at advanced stages.

[The establishment of a systematic site-specific metastasis model of human hepatocellular carcinoma in nude mouse].

To establish a systematic site-specific metastatsis model of human hepatocellular carcinoma (HCC) in nude mouse. HCCLM3-R cells were seeded into mice liver to establish xenograft mouse models. With the help of RFP, metastasis foci in lungs and lymph nodes in mice were detected using fluorescent stereomicroscopy and were removed. Cells derived from the metastasis foci were named HCCLM3-R-LM1 and HCCLM3-R-LnM1 respectively. HCCLM3-R-LM1 and HCCLM3-R-LnM1 cells were seeded into mice livers to analyze the lung and lymph node metastasis. Lungs of all tested mice were collected, examined by pathological evaluation and counted lung metastasis. Both lung and lymph node metastasis were found in HCCLM3-R-LM1, HCCLM3-R and HCCLM3-R-LnM1 cells and a significant difference was found between the lung and the lymph node metastasis levels in the three cells. The fluorescent areas (pixels) of lung and lymph node metastasis were 8687.00+/-1844.63 versus 2570.00+/-318.20 (P = 0.0031) in HCCLM3-R-LM1 cells, 6457.67+/-832.62 versus 10 994.33+/-2 212.31 (P = 0.0036) in HCCLM3-R cells, and 2968.67+/-2571.00 versus 24 416.00+/-7 186.13 (P = 0.0094) in HCCLM3-R-LnM1 cells, respectively. The middle numbers of microscopic lung metastatic foci were 775, 430 and 310 in HCCLM3-R-LM1, HCCLM3-R and HCCLM3-R-LnM1 cells (P less than 0.001), respectively, consist with the results quantified by RFP. We established the systematic site-specific metastasis models which demonstrates lung- and lymph node-specific metastasis potential in nude mice and can be used as a model for researches on site-specific metastasis of HCC.

[Effects of ARNT2 gene on invasion and migration of human hepatocellular carcinoma HCCLM6 cell line].

OBJECTIVE: To investigate the effects of ARNT2 on invasion and migration of HCCLM6 cells. METHODS: Four short hairpin oligos targeting to ARNT2 were s cloned into the pLVTHM vector. Lentiviral vectors shRNA-ARNT2i, pCMV-dR8.74 and pMD2G were cotransfected into 293T cells using Lipofectamine 2000. HCCLM6 was infected with virus supernatant. ARNT2 mRNA and protein expressions were detected using quantitative Real time-PCR and Western blot, respectively. The invasion and migration of HCCLM6 cells were evaluated using wound healing assay and cell invasion assay in vitro. Statistical analysis was performed with SPSS 16.0. RESULTS: The relative mRNA levels of ARNT2 were 0.154+/-0.024, 0.860+/-0.145, 1.004+/-0.009 in shRNA-ARNT2i virus infected HCCLM6 cells, mock-infected cells and control vector virus infected cells (F = 113.14, P more than 0.01). The expression of ARNT2 at protein level was 16.45+/-1.6, 44.56+/-2.07 in the HCCLM6 cells infected with shRNA-ARNT2i virus and negative control vector virus, respectively (t = 18.58, P less than 0.01). The scrape wound of HCCLM6 cells infected with shRNA-ARNT2i virus healed faster than cells infected with control vector virus or mock-infected cells. The number of cells invading through Matrigel was higher in the HCCLM6 cells infected with shRNA-ARNT2i virus (13.25+/-1.04) than that in mock-infected HCCLM6 cells and the HCCLM6 cells infected with negative control vector virus (6.50+/-2.56, 6.75+/-2.05) (F = 29.645, P less than 0.01). CONCLUSION: Inhibition of ARNT2 gene promotes the invasion and migration of HCCLM6 cells.

Maintenance chemotherapy is effective in patients with metastatic triple negative breast cancer after first-line platinum-based chemotherapy.

BACKGROUND: Platinum-based chemotherapy (PBCT) has gained an important position as a first-line treatment for metastatic triple-negative breast cancer (mTNBC). We assessed whether maintenance chemotherapy maintenance was superior to observation after first-line PBCT in patients with mTNBC. METHODS: A total of 265 patients with mTNBC who had exhibited non-PD after 4-6 cycles of firstline PBCT at the Fudan University Shanghai Cancer Center from January 2008 to April 2019 were retrospectively analyzed. 107 patients who did not receive additional treatment were defined as the control observation group, and the remaining 158 patients who continued to receive maintenance therapy were defined as the maintenance treatment group. RESULTS: The median progression-free survival (PFS) time in the maintenance group was 9.63 months, which was significantly longer than the PFS time of 7.47 months in the observation group (HR 0.49, 95% CI: 0.37-0.67, P<0.0001). The median overall survival (OS) of the observation group and the maintenance group was 25.37 months and 31.27 months, respectively (HR 0.65, 95% CI: 0.44-0.95, P=0.019). The survival benefit was still present after adjusting baseline characteristics. Moreover, multivariate analyses suggested that maintenance chemotherapy is an independent predictive factor for both PFS and OS. Interaction and stratified analyses showed no difference in the PFS with between the single-drug maintenance strategy, single agent or doublet group and the doublet-drug maintenance group. The most common adverse event in this study was hematologic toxicity. Except for hand-foot syndrome (0 vs. 7.6%, P=0.004), the incidence of other adverse events was not significantly different between the observation and maintenance groups. CONCLUSIONS: After achieving non-PD with the first-line PBCT in mTNBC patients, chemotherapy maintenance may provide OS benefit prior to the era of biologicals.

[Preparation and in vitro study of buagafuran solid dispersions].

Solid dispersions technique was used to solidify buagafuran and improve buagafuran in vitro dissolution and stability. Buagafuran solid dispersions were prepared separately using PVPK30, PEG6000 and Poloxamer188 at various weight ratios as carriers. The status of buagafuran in solid dispersions was determined by using DSC and IR. The solubility, content and in vitro dissolution of pure drug and the solid dispersions were detected by using HPLC. When buagafuran/carrier was 1:5 or less, the drug existed in a solid dispersion form. Three kinds of carriers all can improve buagafuran dispersibility and in vitro dissolution. Accelerating experiment showed that buagafuran/PVPK30 < or = 1:10 solid dispersions was ageing-resistant, and the aspect, content and in vitro dissolution did not change after storaged over 3 months, but PEG6000, Poloxamer188 and a lower ratio PVPK30 solid dispersions became aged. Buagafuran/PVPK30 < or = 1:10 solid dispersions can be developed as buagafuran oral drug delivery carrier.

Src Inhibition Can Synergize with Gemcitabine and Reverse Resistance in Triple Negative Breast Cancer Cells via the AKT/c-Jun Pathway.

PURPOSE: Gemcitabine-based chemotherapy remains one of the standards in management of metastatic breast cancer. However, intrinsic and acquired resistance to gemcitabine inevitably occurs. The aims of this study were to assess the efficacy of the combination of src inhibition and gemcitabine in gemcitabine-resistant breast cancer cells. METHODS AND RESULTS: By using colony formation, sphere forming, flow cytometry, cell counting kit-8 and transwell assays, 231/GEM-res (gemcitabine-resistant) cell line, which was 10 times more resistant, was shown to have elevated drug tolerance, enhanced proliferative and self-renewal abilities, compared with its parental cells. Inhibition of src by both saracatinib (AZD0530) and siRNA could partially reverse gemcitabine resistance and attenuate resistance-associated anti-apoptosis, migration and stem cell capacities. In addition, the combination of src inhibition and gemcitabine had synergistic antitumor effects. Western blot analysis revealed up-regulation of pro-apoptotic protein BAX, along with the down-regulation of anti-apoptotic proteins (BCL-XL, Survivin), migration associated proteins (p-FAK, MMP-3) and cancer stem cell (CSC) markers (CD44, Oct-4), which was probably mediated by AKT/c-Jun pathway. CONCLUSION: In highly gemcitabine-resistant 231 cells, src inhibition can synergize with gemcitabine, reverse drug resistance, inhibit tumor growth/metastasis/stemness of cancer stem cells, possibly via the AKT/c-Jun pathway.

miR-612 suppresses the invasive-metastatic cascade in hepatocellular carcinoma.

MicroRNAs (miRNAs) play a critical role in tumor metastasis. In this study, we identified a set of 32 miRNAs involved in hepatocellular carcinoma (HCC) metastasis. Among them, miR-612 was shown for the first time to have inhibitory effects on HCC proliferation, migration, invasion, and metastasis. AKT2 was verified to be one of the direct targets of miR-612, through which the epithelial-mesenchymal transition (EMT) and metastasis were inhibited. The level of miR-612 in HCC patients was inversely associated with tumor size, stage, EMT, and metastasis. Of particular importance, miR-612 is involved in both the initial and final steps of the metastatic cascade, by suppressing local invasion and distant colonization. The pleiotropic roles of miR-612 in the HCC metastatic cascade suggest that it could be an effective target for both early and advanced HCC.

Metadherin promotes hepatocellular carcinoma metastasis through induction of epithelial-mesenchymal transition.

PURPOSE: To investigate the expression of metadherin (MTDH) for its prognostic value in hepatocellular carcinoma (HCC) and its role in promoting HCC metastasis. EXPERIMENTAL DESIGN: This study employed a tissue microarray containing samples from 323 HCC patients to examine the expression of MTDH and its correlation with other clinicopathologic characteristics. The role of MTDH in the regulation of HCC metastasis was investigated both in vitro and in vivo using short hairpin RNA (shRNA)-mediated downregulation of MTDH in HCC cell lines with various metastatic potentials. RESULTS: The expression of MTDH was markedly higher in HCC tumors than in normal liver tissue. Particularly high MTDH expression was observed in tumors with microvascular invasion, pathologic satellites, poor differentiation, or tumor-node-metastasis stages II to III. Furthermore, the clinical outcome was consistently poorer for the MTDH(high) group than for the MTDH(low) group in the 1-, 3-, and 5-year overall survival (OS) rates and in the 1-, 3-, 5-year cumulative recurrence rates. In a nude mice model, the shRNA-mediated downregulation of MTDH resulted in a reduced migratory capacity in HCC cell lines, as well as a reduction in pulmonary and abdominal metastasis. Furthermore, we found that the expression level of MTDH correlated with four epithelial-mesenchymal transition (EMT) markers. Knockdown of MTDH expression in HCC cell lines resulted in downregulation of N-cadherin and snail, upregulation of E-cadherin, and translocation of ß-catenin. CONCLUSIONS: MTDH may promote HCC metastasis through the induction of EMT process and may be a candidate biomarker for prognosis as well as a target for therapy.