Inhibitory effects of antisense RNA of HAb18G/CD147 on invasion of hepatocellular carcinoma cells in vitro

The clinicopathological significance and prognostic value of EMMPRIN overexpression in cancers: evidence from 39 cohort studies

Extracellular matrix metalloproteinase inducer (EMMPRIN) has been reported to be associated with tumor formation and invasion in many studies. However, the clinicopathological significance and prognosis of EMMPRIN in cancer patients remains inconclusive. Therefore, we conducted a meta-analysis to assess the predictive potential of EMMPRIN in various cancers. By searching Pubmed, Cochrane library database and web of science comprehensively, 39studies with 5739 cases were included in our meta-analysis. The results indicated that EMMPRIN overexpression was significantly associated with poor outcome of cancers (HR=2.46, 95% CI: 2.21-2.75, P<0.0001). In addition, a significant relation was found between EMMPRIN overexpression and clinicopathological features, such as tumor stage (T3+T4/ T1+T2, OR=1.87, 95% CI:1.64-2.12, P<0.0001), tumor differentiation (poor/ well+ moderate, OR=1.09, 95% CI:1.60-2.23, P<0.0001), clinical stage (III+IV /I +II, OR=1.96, 95% CI:1.69-2.27, P<0.0001) and nodal metastasis (positive/negative, OR=2.37, 95% CI:1.93-2.90, P<0.0001). However, the expression of EMMRIN was not significantly associated with tumor stage in cervical cancer (OR=1.35, 95%CI: 0.73-2.48, P=0.33). In conclusion, EMMPRIN overxepression is significantly associated with clinicopathological characteristics and prognosis of cancers. Thus, EMMPRIN may be regarded as a promising bio-marker in predicting the clinical outcome of patients in cancers and could be used as the therapeutic target during clinical practices.

Silencing of advanced glycosylation and glycosylation and product-specific receptor (RAGE) inhibits the metastasis and growth of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) constitutes the main cases of lung cancer and is the world's most common and lethal cancer owing to regional invasion or distant metastasis. Growing morbidity and lethality demonstrates that valid molecular target in management of NSCLC metastasis is still absence. The receptor of advanced glycation end-products (RAGE) has been identified as an oncogenic gene and appears to promote the growth and metastasis of various cancers. Here, we investigated if RAGE targeted by RNA interference (RNAi) might have certain effect on the restraint of the growth of NSCLC and tumor metastasis. Wound healing and Transwell invasion assays indicated that RAGE favored the metastatic capabilities of NSCLC H1975 cells. Besides, soft-agar colony assay revealed that silencing RAGE significantly blocked colony-forming capability of H1975 cells in vitro. Furthermore, we observed that RAGE participated in H1975 cells growth, metastasis and epithelial-mesenchymal transition (EMT) by regulating interdict crux intracellular signaling pathways, including phosphatidylinositol-3 kinase/serine-threonine kinase (PI3K/AKT) and V-Ki-ras2 kirsten rat sarcoma viral oncogene homolog/RAF proto-oncogene serine/threonine-protein kinase (KRAS/RAF-1). In xenograft model, significantly reduction intumor growth and Ki67 expression was demonstrated in nude mice inoculation with RAGE down-regulation H1975 cells. To conclude, our study demonstrated that RAGE played a crucial role in the metastasis and growth of NSCLC by regulating PI3K/AKT and KRAS/RAF-1 signaling pathways, thereby might be a promising therapeutic target for NSCLC.

Sp1-CD147 positive feedback loop promotes the invasion ability of ovarian cancer

CD147 is a novel cancer biomarker that has been confirmed to be overexpressed in ovarian carcinoma, which is significantly associated with poor prognosis. Although the Sp1 protein regulates the expression level of CD147, it remains unclear whether Sp1 phosphorylation plays a role in this regulation. A dual-luciferase assay revealed that T453 and T739 mutations decreased the activity of Sp1 binding to the promoter of CD147, followed by a decrease in CD147 mRNA and protein expression. Western blot analysis showed that CD147 promoted Sp1 phosphorylation at T453 and T739 through the PI3K/AKT and MAPK/ERK pathways. In addition, blocking the Sp1-CD147 positive feedback loop reduced the invasion ability of HO-8910pm cells. Immunohistochemical staining showed that the components of the feedback loop were overexpressed in ovarian cancer tissues. The correlation analysis revealed a significant correlation between phospho-Sp1 (T453), phospho-Sp1 (T739) and CD147 expression levels, with correlation coefficients of r=0.477 and r=0.461, respectively. Collectively, our results suggest that a Sp1-CD147 positive feedback loop plays a critical role in the invasion ability of ovarian cancer cells.

A chimeric antibody targeting CD147 inhibits hepatocellular carcinoma cell motility via FAK-PI3K-Akt-Girdin signaling pathway

CD147 is expressed at low levels in normal tissues but frequently highly expressed in a wide range of tumor types such as lung, breast, and liver and therefore it is a potentially unique therapeutic target for these diverse tumor types. We previously generated a murine antibody HAb18 which suppresses matrix met al.loproteinase-2 and matrix metalloproteinase-9 secretion, attenuates cell invasion by blocking the CD147 molecule in tumor cells. Here, we generated a chimeric antibody containing the variable heavy and variable light chains of murine HAb18 and the constant regions of human IgG1γ1 and human κ chain as a potential therapeutic agent (designated cHAb18). Quantitative measurement of cHAb18 antibody affinity for antigen CD147 with surface plasmon resonance showed the equilibrium dissociation constant KD was 2.66 × 10(-10) mol/L, similar to that of KD 2.73 × 10(-10) mol/L for murine HAb18. cHAb18 induced antibody-dependent cell-mediated cytotoxicity in two hepatocellular carcinoma cell lines, SMMC-7721 and Huh-7 cells. It inhibited cancer invasion and migration in hepatocellular carcinoma cells by specifically blocking CD147. Except for the depression of matrix metalloproteinase-2 and matrix metalloproteinase-9 expressions, cHAb18 antibody suppressed cell motility by rearrangement of actin cytoskeleton, which was probably induced by decreasing the phosphorylation of focal adhesion kinase, phosphatidylinositide-3 kinase (PI3K), Akt, and Girdin in the integrin signaling pathway. In an orthotopic model of hepatocellular carcinoma in BALB/c nude mice, cHAb18 treatment effectively reduced the tumor metastasis in liver and prolonged the survival. These findings reveal new therapeutic potential for cHAb18 antibody targeting CD147 on tumor therapy.

High expression of CD147 and MMP-9 is correlated with poor prognosis of triple-negative breast cancer (TNBC) patients

The aim of this study was to investigate expression of CD147 and MMP-9 in triple-negative breast cancer (TNBC) so as to determine whether these two proteins may be correlated with poor prognosis of TNBC patients. We examined the expression levels of the CD147 and MMP-9 in 127 patients with TNBC and 30 patients with mammary gland fibroma using immunohistochemical staining before any treatments. Furthermore, we analyzed the correlation between the expression of these two proteins and various clinicopathologic factors including survival status of patients with TNBC. Positive stain of CD147 and MMP-9 was observed in all samples of TNBC. A statistically positive correlation was observed between the expression levels of CD147 and MMP-9 in TNBC tissues. The incidences of high expression were 48.0 % for CD147 and 53.5 % for MMP-9 in 127 TNBC tissues, respectively. High expression of either CD147 or MMP-9 was significantly correlated with clinical feature and shorter progression-free survival (PFS) (P(CD147) = 0.039; P(MMP-9) = 0.017) and overall survival (OS) (P(CD147) = 0.037; P(MMP-9) = 0.023). The expression levels of CD147 and MMP-9 are positively correlated with invasion, metastasis and shorter PFS/OS of TNBC. Patients with high expression of CD147 and MMP-9 had poor prognosis than TNBC patients with low expression.

Hepatic artery injection of ¹³¹I-labelled metuximab combined with chemoembolization for intermediate hepatocellular carcinoma: a prospective nonrandomized study

PURPOSE

Hepatocellular carcinoma (HCC) is the fifth and seventh most common cause of cancer in men and women, respectively. Transcatheter arterial chemoembolization (TACE) is the standardized therapy for the intermediate stage of HCC. However, the 3-year overall survival remains low (<30 %) in these patients. Thus, there is a critical need for the development of treatment modalities to improve the survival rate. This study aimed to evaluate whether the combination of (131)I-metuximab with chemoembolization could improve treatment efficiency.

METHODS

Between January 2009 and January 2010, a prospective two-arm nonrandomized study was performed in patients with intermediate HCC. Of 138 patients, 68 (combination therapy group) received 132 courses of intraarterial (131)I-metuximab injections combined with chemoembolization (mean 1.94 per patient, median 2, range 1-2), followed by 152 sessions of TACE (mean 2.24 per patient, median 2, range 0-4). The remaining 70 patients (monotherapy group) received 296 sessions of TACE (mean 4.23 per patient, median 4, range 1-7).

RESULTS

The overall median survival times for the combination therapy group and the group treated only with TACE were 26.7 months (95 % CI 20.7-31.3 months) and 20.6 months (95 % CI 15.3-24.7 months), respectively. The combination therapy group had a significantly higher survival rate than the TACE-only group (P = 0.038). Age ≥65 years, serum albumin ≤35 g/l, and treatment category (combination therapy or TACE only) were independent prognostic factors for survival according to multivariate analysis.

CONCLUSION

The combination of (131)I-metuximab and chemoembolization extended survival in patients with intermediate HCC compared with TACE only, and was well tolerated by patients with Child-Pugh class A or B disease. This combination seems to be a promising treatment modality for patients with intermediate HCC.

Hepatic arterial iodine-131-labeled metuximab injection combined with chemoembolization for unresectable hepatocellular carcinoma: interim safety and survival data from 110 patients

Few options are available to treat patients with hepatocellular carcinoma (HCC). It was tested whether the combination of iodine-131(¹³¹I)-metuximab with chemoembolization could improve outcomes in patients with intermediate HCC. Between April 2008 and April 2009, 110 patients with unresectable HCC were treated with 113 intra-arterial ¹³¹I-metuximab injections combined with chemoembolization (mean, 1.03 per patient; median, 1; range, 1-2), followed by 264 sessions of transcatheter arterial chemoembolization (mean, 2.4 per patient; median, 3; range, 1-6). The survival rates at 6, 12, and 18 months were 88.2%, 79.1%, and 57.4%, respectively, by the Kaplan-Meier method. Of these patients, 12% exhibited grade 3/4 bilirubin toxicity, 5% exhibited grade 3/4 white blood count toxicity, and 7% exhibited grade 3/4 platelet toxicity. Response rates based on World Health Organization and European Association for the Study of the Liver criteria were 42.73% and 61.82%, respectively. The combination of ¹³¹I-metuximab and chemoembolization appeared to extend survival in patients with unresectable HCC compared with historical controls, as well as being well tolerated by patients with Child-Pugh A and B. This combination may represent a promising treatment modality for patients with intermediate HCC.

Expression of CD147 is associated with prostate cancer progression

Novel molecular markers that are associated with prostate cancer (PCa) progression will provide valuable information in the diagnosis and treatment of the disease. Extracellular matrix metalloproteinase inducer (CD147) has been demonstrated to be involved in tumor invasion, metastasis, growth and survival. In our study, we examined whether the expression of CD147 can be used as a prognostic marker for predicting PCa progression. Tissue samples from 240 patients who received radical prostatectomy for PCa were obtained. CD147 expression in these samples was evaluated using immunohistochemical staining with a monoclonal antibody specifically against CD147. Increased expression of CD147 was correlated with higher Gleason scores (GS), positive surgical margin, prostate-specific antigen (PSA) failure, metastasis and reduced overall survival. Both univariate Cox regression analysis and multivariate analysis including competing biological variables demonstrated that increased CD147 expression was associated with increased risk for reduced PSA failure-free, metastasis-free and overall survival. Kaplan-Meier survival curves showed that the CD147 overexpression was a significant predictor for the PSA failure-free, metastasis-free and the overall survival in both pT2 and pT3 PCa patients. More significantly, higher expression of CD147 can serve as an independent prognostic predictor for PSA failure-free survival in PCa patients when they are stratified by GS. Our study results demonstrate the involvement of CD147 in PCa progression and suggest its potential role as an independent predictor of biochemical recurrence, development of metastasis and reduced overall survival in PCa.

CD147 overexpression is a prognostic factor and a potential therapeutic target in bladder cancer

CD147, also named extracellular matrix metalloproteinase inducer (EMMPRIN), has been shown to be involved in the progression of malignancy by regulating expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). The goal of this study was to evaluate the role of CD147 in the biology of bladder cancer and to determine its potential as a therapeutic target. CD147 protein expression was detected by immunohistochemistry in 108 bladder cancers using a tissue microarray annotated with patient follow-up. In immunohistochemistry, CD147 protein expression was associated with poor prognosis (P<0.001), lymph node status (P<0.001), tumor stage (P=0.003), histologic grade (P=0.011). Multivariate analysis showed that CD147 overexpression was an independent prognostic factor (P=0.019). Infection of T24 bladder cancer cells with an adenovirus that expressed a small interfering RNA (siRNA) against CD147 efficiently inhibited CD147 protein and mRNA expression. This resulted in decreased proliferation, soft agar colony formation, migration, and invasion of T24 cells in vitro. Moreover, downregulation of CD147 reduced secretion of MMP-2 and MMP-9 and expression of VEGF in these cells. Our findings suggest that CD147 overexpression plays an important role in progression of bladder cancer, and CD147 could be a potential target of bladder cancer therapy.

Expression of HAb18G is associated with tumor progression and prognosis of breast carcinoma

HAb18G is a recently identified hepatoma-associated antigen and its association with tumor growth, invasion, and angiogenesis has been studied in a variety of tumors. However, its role in the tumor progression of breast cancer has not been explored. HAb18G expression was examined by immunohistochemistry in pathological sections of 1,637 breast tissue samples and by in situ hybridization in 41 cases of invasive breast carcinomas (BC). While not detected in any cases of tumor-like conditions or benign tumors of breast, and only rarely in normal tissue (4.4%), HAb18G expression was gradually up-regulated from atypical ductal hyperplasia (27.3%), to ductal carcinoma-in situ (59.8%), and to BC (61.4%) (P < 0.01). Its expression in BC was correlated positively with C-erbB-2 expression and histologic grade (P < 0.001), and negatively with the expression of estrogen and progesterone receptors (P < 0.001). Significant differences of expression were also identified among the subgroups of BC examined: in decreasing order from invasive micropapillary carcinoma, ductal carcinoma, lobular carcinoma, papillary carcinoma, medullary carcinoma, to mucinous adenocarcinoma (P = 0.001), corresponding to their known clinical aggressiveness. In an expanded group of 186 BC patients with proper follow up, our previous findings were confirmed: HAb18G expression was significantly associated with local recurrence, distant metastasis and tumor mortality (P < 0.01). We also demonstrated that up-regulated tumor expression of HAb18G was a significant predictor of reduced disease progression-free survival rate and a shorter overall survival, independent of systemic therapies. In conclusion, this study suggests that HAb18G expression is associated with BC progression and prognosis. Further evaluation of this new marker in breast cancer is indicated.

Tumor metabolism of lactate: the influence and therapeutic potential for MCT and CD147 regulation

Tumor metabolism consists of complex interactions between oxygenation states, metabolites, ions, the vascular network and signaling cascades. Accumulation of lactate within tumors has been correlated with poor clinical outcomes. While its production has negative implications, potentially contributing to tumor progression, the implications of the ability of tumors to utilize lactate can offer new therapeutic targets for the future. Monocarboxylate transporters (MCTs) of the SLC16A gene family influence substrate availability, the metabolic path of lactate and pH balance within the tumor. CD147, a chaperone to some MCT subtypes, contributes to tumor progression and metastasis. The implications and consequences of lactate utilization by tumors are currently unknown; therefore future research is needed on the intricacies of tumor metabolism. The possibility of metabolic modification of the tumor microenvironment via regulation or manipulation of MCT1 and CD147 may prove to be promising avenues of therapeutic options.

CD147 expression indicates unfavourable prognosis in prostate cancer

Extracellular matrix metalloproteinase inducer (EMMPRIN, also named as CD147) is a multifunctional membrane glycoprotein over-expressed in many kinds of human solid tumors. It has been demonstrated to be involved in tumor invasion and angiogenesis. The aim of this study was to analyze the clinicopathological characteristics of the expression of CD147 in human prostate cancer (PCa), and to evaluate its clinical significance in the histologic classification and prognosis of PCa. CD147 protein expression in paraffin-embedded specimens gathered from 62 cases of PCa and 30 cases of benign prostatic hyperplasia (BPH) were detected by the method of immunohistochemistry. The association of CD147 protein expression with the clinicopathological characteristics and with the prognosis of PCa was subsequently assessed. CD147 expression were positively expressed in 51/62 (82.3%) of PCa and 4/30 (13.3%) of BPH cases, respectively. The positive expression rate of CD147 in PCa tissues was significantly higher than that in BPH. The positive expression of CD147 was dramatically associated with TNM grade (p < 0.001), the depth of the prostatic wall invasion (p = 0.008), GLEASON Score (p = 0.001) and Histologic grade (p = 0.001). The patients with CD147 expression were associated with a poor prognosis of PCa (p = 0.01) and the survival rate of the patients with a strong positive expression of CD147 was the lowest (p = 0.01). The results suggest that the expression of CD147 may be an important feature of PCa and the detection of its expression may benefit us in the prediction of the prognosis of PCa.

HAb18G (CD147), a cancer-associated biomarker and its role in cancer detection

AIMS

To evaluate HAb18G/CD147 as a cancer-associated biomarker using its monoclonal antibody HAb18.

METHODS AND RESULTS

On immunohistochemical analysis of 28 tissue microarrays and pathological sections of 1117 breast tissue samples, HAb18G/CD147 was expressed in carcinoma with an overall positivity rate of 67.76%, which was significantly higher than that in sarcomas (27.34%, P < 0.0001) and normal epithelial (5.18%, P < 0.0001) and fetal (2.67%, P < 0.0001) tissues. In epithelial tissues from 14 organs, the difference in HAb18G/CD147 expression between normal epithelium and the corresponding carcinoma was also significant (P < 0.05 for each pair). This expression in carcinoma was also found at the mRNA level, suggesting transcriptional level regulation of HAb18G/CD147 expression. In a retrospective study of 106 patients with infiltrating ductal carcinoma of the breast, the level of HAb18G/CD147 expression was positively correlated with tumour recurrence/metastasis (P = 0.0003) and negatively correlated with survival of breast cancer patients (P = 0.002). Multivariable Cox regression analysis showed that HAb18G/CD147 was an independent prognostic factor.

CONCLUSIONS

HAb18G/CD147 is significantly expressed in various cancers and appears to have prognostic significance, rendering it a possible cancer-associated biomarker for pathological diagnosis, prognostic evaluation, targeted therapy and radioimmunoimaging of a broad range of cancer types.

Expression of MMP9 and CD147 in invasive squamous cell carcinoma of the uterine cervix and their implication. Pathol Res Pract. 2009;205:709-715. [PMID: 19541433 DOI: 10.1016/j.prp.2009.05.010]

Matrix metalloproteinase 9 (MMP9) and CD147 play a role in invasion and metastasis of many types of human malignancies. The correlation of the expression of MMP9 and CD147 with invasion and metastasis of invasive squamous cell carcinoma (SCC) of the uterine cervix has not been examined. In the present study, RT-PCR assay was used to detect the expression level of MMP9 mRNA semiquantitatively, and immunohistochemical stain was adapted to evaluate the score of CD147 on the cell membrane or in the cytoplasm of tumor cells of 65 cases of invasive squamous cell carcinoma of the uterine cervix and 21 cases of chronic cervitis tissues. MMP9 and CD147 expression in correlation with invasion, metastasis, and differentiation of invasive SCC of the uterine cervix was analyzed statistically. We found that MMP9 and CD147 expression was elevated significantly in tumor tissue compared to the control (cervical epithelium of chronic cervitis) (P<0.01). In the comparison of MMP9 and CD147 expression in 47 cases with lymph node metastasis and 18 cases without lymph node metastasis, there was a significantly higher expression of MMP9 and CD147 in the group with lymph node metastasis (P<0.05 for MMP9, P<0.01 for CD147). MMP9 expression was significantly higher in 24 cases of poor differentiation than in 41 cases of moderate differentiation (P<0.05). No difference was found in CD147 expression between poor and moderate differentiation (P>0.05). No significant difference in MMP9 and CD147 expression levels was obtained between 26 cases of FIGO stage I tumors and 39 cases of stage II tumors (P>0.05 for MMP9, P>0.05 CD147). There was no correlation between MMP9 or CD147 expression levels and the resected tumor size (P>0.05). The positive correlation (r=0.568, P<0.001) of MMP9 expression and CD147 score was seen in the tumor tissues of 65 cases. The data in this study show that MMP9 and CD147 expression are correlated with invasion, metastasis of squamous cell carcinoma of the uterine cervix, and that MMP9 expression is correlated with poor differentiation of invasive squamous cell carcinoma of the uterine cervix.

Role and significance of focal adhesion proteins in hepatocellular carcinoma

Focal adhesions are structural links between the extracellular matrix and actin cytoskeleton. They are important sites where dynamic alterations of proteins in the focal contacts are involved during cell movement. Focal adhesions are composed of diverse molecules, for instance, receptors, structural proteins, adaptors, GTPase, kinases and phosphatases. These molecules play critical roles in normal physiological events such as cellular adhesion, movement, cytoskeletal structure and intracellular signaling pathways. In cancers, aberrant expression and altered functions of focal adhesion proteins contribute to adverse tumor behavior. It is evident that these proteins do not function alone, but rather associate and work together in the process of tumor development and cancer metastasis. Focal adhesion proteins have been shown to play critical roles in hepatocellular carcinoma. Understanding the molecular interactions and mechanisms of the interconnected focal adhesion proteins is of particular importance in understanding mechanisms underlying hepatocellular carcinoma progression and development of potential effective treatment.

Association of TMPRSS2 and KLK11 gene expression levels with clinical progression of human prostate cancer

AIM

The aim of this study was to analyze the clinicopathological characteristics of TMPRSS2 and KLK11 gene expression levels in human prostate cancer (PCa), and to evaluate their clinical significance in the progression of PCa.

METHODS

The expression of prostate-type and brain-type isoforms of KLK11 gene, and TMPRSS2 gene was analyzed by quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) in 63 PCa tissues. The correlation of TMPRSS2 and KLK11 gene expression with the clinicopathological characteristics and with the prognosis of PCa was subsequently assessed.

RESULTS

The mean values of TMPRSS2 (3.91 +/- 0.78 in PCa vs. 0.26 +/- 0.04 in normal prostate tissues) and both isoforms of KLK11 (prostate-type: 3.63 +/- 0.42 in PCa vs. 0.49 +/- 0.07 in normal prostate tissues; brain-type: 3.11 +/- 0.30 in PCa vs. 0.46 +/- 0.05 in normal prostate tissues) were significantly higher in cancer tissues compared with their normal counterparts. We found a significant positive correlation between TMPRSS2 expression and tumor stage (P = 0.02), Gleason score (P = 0.008), and tumor grade (P = 0.016). Regarding prostate-type KLK11, we identified a significant association between lower expression and higher tumor stage (P = 0.009), Gleason score (P = 0.01), and tumor grade (P = 0.006). No such association was seen with the brain-type isoform. The survival rate of the patients with TMPRSS2-high/KLK11-low expression was lowest (P = 0.003).

CONCLUSION

The results suggest that the up-regulation of TMPRSS2 gene and the down-regulation of KLK11 gene in advanced and more aggressive tumors may open the feasibility of being used as biomarkers distinguishing the tumor aggressiveness as well as novel prognostic indicators for PCa.

Downregulation of CD147 expression alters cytoskeleton architecture and inhibits gelatinase production and SAPK pathway in human hepatocellular carcinoma cells

BACKGROUND

CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this study is to investigate the effects of small interfering RNA (siRNA) against CD147 (si-CD147) on hepatocellular carcinoma cells' (SMMC-7721) architecture and functions.

METHODS

Flow cytometry and western blot assays were employed to detect the transfection efficiency of si-CD147. Confocal microscopy was used to determine the effects of si-CD147 on SMMC-7721 cells' cytoskeleton. Invasion assay, gelatin zymography and cell adhesion assay were employed to investigate the effects of si-CD147 on SMMC-7721 cells' invasion, gelatinase production and cell adhesive abilities. Western blot assay was utilized to detect the effects of si-CD147 on focal adhesion kinase (FAK), vinculiln and mitogen-activated protein kinase (MAPK) expression in SMMC-7721 cells.

RESULTS

Downregulation of CD147 gene induced the alteration of SMMC-7721 cell cytoskeleton including actin, microtubule and vimentin filaments, and inhibited gelatinase production and expression, cells invasion, FAK and vinculin expression. si-CD147 also blocked SMMC-7721 cells adhesion to collagen IV and phosphorylation level of SAPK/JNKs. SAPK/JNKs inhibitor SP600125 inhibited gelatinase production and expression.

CONCLUSION

CD147 is required for normal tumor cell architecture and cell invasion. Downregulation of CD147 affects HCC cell structure and function. Moreover, the alteration of cell behavior may be related to SAPK/JNK Pathway. siRNA against CD147 may be a possible new approach for HCC gene therapy.

A protein chip approach for high-throughput antigen identification and characterization

Proteomics research in humans and other eukaryotes demands a large number of high-quality mAbs. Here, we report a new approach to produce high-quality mAbs against human liver proteins using a combined force of high-throughput mAb production and protein microarrays. After immunizing mice with live cells from human livers, we isolated 54 hybridomas with binding activities to human cells and identified the corresponding antigens for five mAbs via screening on a protein microarray of 1058 unique human liver proteins. Finally, we demonstrated that using the five mAbs we could characterize the expression profiles of their corresponding antigens by using tissue microarrays. Among them, we discovered that eIF1A expressed only in normal liver tissues, not in hepatocellular carcinoma in humans.

Inhibition of CD147 gene expression via RNA interference reduces tumor cell invasion, tumorigenicity and increases chemosensitivity to paclitaxel in HO-8910pm cells

Overexpression of extracellular matrix metalloproteinase inducer (EMMPRIN or CD147), a member of the immunoglobulin family and a glycoprotein enriched on the surface of tumor cells, promotes invasion, metastasis, growth and survival of malignant cells, and confers resistance to some chemotherapeutic drugs. Here, we used a human U6 promoter-driven DNA template approach to induce short hairpin RNA (shRNA)-triggered RNA interference (RNAi) to block CD147 gene expression in the human ovarian cancer cell line HO-8910pm. Knockdown of CD147 by shRNA resulted in decrease of the HO-8910pm invasion activity in vitro and tumorigenicity in nude mice. The suppression of CD147 expression also sensitized cells to be more sensitive to paclitaxel. These results suggested that CD147 was an ovarian cancer-related gene and CD147 might be a potential target for therapeutic anti-cancer drugs.

Targeting radioimmunotherapy of hepatocellular carcinoma with iodine (131I) metuximab injection: clinical phase I/II trials

PURPOSE

HAb18G/CD147 is a hepatocellular carcinoma (HCC)-associated antigen. We developed iodine (131I) metuximab injection (Licartin), a novel 131I-labeled HAb18G/CD147-specific monoclonal antibody Fab'2 fragment, and evaluated its safety, pharmacokinetics, and clinical efficacy on HCC in Phase I/II trials.

METHODS AND MATERIALS

In a Phase I trial, 28 patients were randomly assigned to receive the injection in 9.25-, 18.5-, 27.75-, or 37-MBq/kg doses by hepatic artery infusion. In a multicenter Phase II trial, 106 patients received the injection (27.75 MBq/kg) on Day 1 of a 28-day cycle. Response rate and survival rate were the endpoints.

RESULTS

No life-threatening toxic effects were found. The safe dosage was 27.75 MBq/kg. The blood clearance fitted a biphasic model, and its half-life was 90.56-63.93 h. In the Phase II trial, the injection was found to be targeted and concentrated to tumor tissues. Of the 73 patients completing two cycles, 6 (8.22%) had a partial response, 14 (19.18%) minor response, and 43 (58.90%) stable disease. The 21-month survival rate was 44.54%. The survival rate of progression-free patients was significantly higher than that of patients with progressive disease after either one or two cycles (p < 0.0001 or p = 0.0019).

CONCLUSION

Iodine (131I) metuximab injection is safe and active for HCC patients.

Regulation of Matrix Metalloproteinase Production and Tumor Cell Invasion by Four Monoclonal Antibodies Against Different Epitopes of HAb18G/CD147 Extracellular Domain

HAb18G/CD147, a membrane spanning molecule and highly expressed in hepatocellular carcinoma (HCC) cells, was shown to stimulate the production of matrix metalloproteinases (MMPs) in the interaction of tumor cells and fibroblasts. Studies on the EMMPRIN/CD147 showed that CD147 extracellular domain is involved in the induction of MMPs. To study the biological molecular function of HAb18G/CD147 extracellular domain (HAb18G/CD147-ED) on production of MMPs following mediated tumor cell invasion, we isolated four novel monoclonal anibodies (MAbs)-1B3, 3B3, HAb18Gedomab1, and HAb18Gedomab2-against HAb18G/CD147-ED by immunization of BALB/c mice with purified HAb18G/CD147-ED fragments, which were efficiently expressed in Escherichia coli. Gelatin zymography and Boyden chamber assays were used to identify the production of MMPs in the co-cultured human fibroblast and HCC cells, and to quantify the migrated cells in the presence of the generated MAbs. The results showed that two MAbs (1B3 and 3B3) inhibited [corrected] the secretion of MMP-2 and [corrected] the HCC cell invasion, whereas the other two MAbs (HAb18Gedomab1 and HAb18Gedomab2) had reverse function [corrected] FCM additive assay showed that four MAbs recognized different epitopes of HAb18G/CD147-ED. Taken together, the results suggest that various regions of HAb18G/CD147-ED participated in the regulation of MMP secretion.

Function of HAb18G/CD147 in invasion of host cells by severe acute respiratory syndrome coronavirus

To identify the function of HAb18G/CD147 in invasion of host cells by severe acute respiratory syndrome (SARS) coronavirus (CoV), we analyzed the protein-protein interaction among HAb18G/CD147, cyclophilin A (CyPA), and SARS-CoV structural proteins by coimmunoprecipitation and surface plasmon resonance analysis. Although none of the SARS-CoV proteins was found to be directly bound to HAb18G/CD147, the nucleocapsid (N) protein of SARS-CoV was bound to CyPA, which interacted with HAb18G/CD147. Further research showed that HAb18G/CD147, a transmembrane molecule, was highly expressed on 293 cells and that CyPA was integrated with SARS-CoV. HAb18G/CD147-antagonistic peptide (AP)-9, an AP of HAb18G/CD147, had a high rate of binding to 293 cells and an inhibitory effect on SARS-CoV. These results show that HAb18G/CD147, mediated by CyPA bound to SARS-CoV N protein, plays a functional role in facilitating invasion of host cells by SARS-CoV. Our findings provide some evidence for the cytologic mechanism of invasion by SARS-CoV and provide a molecular basis for screening anti-SARS drugs.

Inhibitory effect of antisense oligonucleotide on the expression of survivin gene and proliferation of human hepatocellular carcinoma cell line SMMC-7721

AIM: To investigate the inhibitory effect of survivin antisense oligonucleotide (ASODN) on the expression of survivin gene and proliferation of human hepatocellular carcinoma cell line SMMC-7721.

METHODS: The 20mer antisense oligonucleotide (ASODN) targeted to the promotor region of survivin mRNA was designed and synthesized. The expression of survivin gene in hepatocellular carcinoma cell line SMMC-7721 was blocked by means of ASODN transfection mediated by DOTAP liposomal reagent. The changes of survivin protein and mRNA expression after transfection were assessd by Western blot and in situ hybridization, respectively. The apoptotic rate was detected by flow cytometer. The changes of cell adherent rate, cell growth activity, and the inhibitory rate of cell growth were also studied.

RESULTS: The expression of survivin protein and mRNA was decreased markedly after survivin ASODN transfection (69.59 vs 10.71, and 75.61 vs 22.94, P < 0.01). Meanwhile, the cell adherent rate also decreased markedly (90.68% vs 33.16%, P < 0.01) while the apoptotic rate increased markedly (0.7% vs 31.35%, P < 0.01). The inhibitory effect on the cell growth could maintain about a week after transfection, and the highest inhibitory rate could be 71.8% three d after transfection.

CONCLUSION: Transfection of ASODN targeted to the promotor region of survivin mRNA by DOTAP liposomal transfection reagent can down-regulate the expression of survivin protein and mRNA significantly in 7721 cell line and inhibit the proliferation of cancer cells. survivin may be an important target in the therapy of hepatocellular carcinoma.

Effects of IFN-α on expression of angiogenic factors in highly metastatic human hepatocellular carcinoma cell line HCCLM3 cells

AIM: To study the effects of IFN-α on the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and IL-8 in human hepatocellular carcinoma (HCC) cell line HCCLM3 cells and to explore the mechanism of antiangiogenic activity of IFN-α.

METHODS: The HCCLM3 cells were incubated for 72 h in high glucose Dulbecco's modified Eagle medium (DMEM) (GibocoBRL, NY) or the medium containing different doses of IFN-α (30, 300 or 3 000 kU/L). The concentrations of VEGF, bFGF, MMP-2, MMP-9 and IL-8 in cell culture supernatants were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS: IFN-α treatment significantly decreased the expression of VEGF and MMP-2 in HCCLM3 cells. The concentrations of VEGF, MMP-2, bFGF, and IL-8 were 2 666.0±122.6, 4 400±1 000, 28.0±5.1 and 1 160.0±69.4 ng/L respectively in the control group, whereas those of VEGF, MMP-2, bFGF, and IL-8 were 2 476.5±125.7 (P < 0.05), 2 400±600 (P < 0.01), 25.8±1.6 and 1 079±5 ng/L when the concentration of IFN-α was 300 kU/L. But MMP-9 protein was not detected in all the groups.

CONCLUSION: IFN-α treatment significantly inhibits the expression of VEGF and MMP-2 in HCCLM3 cells in a dose-dependent manner. However, no significant difference is found in the levels of bFGF, IL-8 and MMP-9 among the control and the groups of different doses of INF-a ranging from 30-3 000 kU/L. The down-regulation of VEGF and MMP-2 levels contributes, at least in part, to the antiangiogenic activity of IFN-α.

Effects of metastasis-suppressor gene KAI1 on viscoelastic properties of hepatocellular carcinoma MHCC97-H cells with high metastatic potential

AIM: To study the effects of metastasis-suppressor gene KAI1 on viscoelastic properties of hepatocellular carcinoma MHCC97-H cells with high metastatic potential.

METHODS: The viscoelastic properties of MHCC97-H cells with high metastatic potential transfected with sense or antisense KAI1 expression plasmid in our previous experiments were measured by means of micropipette aspiration technique.

RESULTS: The elastic coefficients K1, K2 and m of the MHCC97-H cells were significantly higher after transfected with sense KAI1 expression plasmid (P = 0.007), lower after transfected with antisense KAI1 expression plasmid (P = 0.000), and no significantly different after transfected with its control vector pCI-neo without KAI1 gene (P = 0.444), as compared with their paternal MHCC97-H cells.

CONCLUSION: The metastasis-suppressor gene KAI1 may significantly affect the viscoelastic properties of MHCC97-H cells with high metastatic potential. It offers an important clue to study the mechanisms of invasion and metastasis of the malignant tumor.

siRNA mediated inhibition of MMP-1 reduces invasive potential of a human chondrosarcoma cell line

Matrix metalloproteinases (MMPs) play a crucial role in tumor cell invasion and metastasis. Expression of MMP-1 has been reported as a prognostic predictor of recurrence in human chondrosarcoma, and studies using human chondrosarcoma cell lines indicate that MMP-1 expression levels correlate with in vitro invasiveness. These observations suggest that MMP-1 activity has a central role in cell egress from the primary tumor at an early step in the metastatic cascade. In this study, siRNA was used to investigate whether knock down of the MMP-1 gene could be used to inhibit invasiveness in a human chondrosarcoma cell line. The inhibitory effect of siRNA on endogenous MMP-1 gene expression and protein synthesis was demonstrated via RT-PCR, Northern blotting, Western blotting, collagenase activity assay, and an in vitro cell migration assay. The siRNA inhibited MMP-1 expression specifically, since it did not affect the expression of endogenous glyceraldehyde phosphate dehydrogenase (GAPDH) nor other collagenases. Most importantly, the siRNA mediated reduction in MMP-1 expression correlated with a decreased ability of chondrosarcoma cells to invade a Type I collagen matrix. The reduction of invasive behavior demonstrated by human chondrosarcoma cells transfected with MMP-1 siRNA and the specificity of this inhibition supports the hypothesis that this metalloproteinase molecule is involved in initiation of chondrosarcoma metastasis.