The role of extracellular matrix metalloproteinase inducer protein in prostate cancer progression

TAGET: a toolkit for analyzing full-length transcripts from long-read sequencing

Single-molecule Real-time Isoform Sequencing (Iso-seq) of transcriptomes by PacBio can generate very long and accurate reads, thus providing an ideal platform for full-length transcriptome analysis. We present an integrated computational toolkit named TAGET for Iso-seq full-length transcript data analyses, including transcript alignment, annotation, gene fusion detection, and quantification analyses such as differential expression gene analysis and differential isoform usage analysis. We evaluate the performance of TAGET using a public Iso-seq dataset and newly sequenced Iso-seq datasets from tumor patients. TAGET gives significantly more precise novel splice site prediction and enables more accurate novel isoform and gene fusion discoveries, as validated by experimental validations and comparisons with RNA-seq data. We identify and experimentally validate a differential isoform usage gene ECM1, and further show that its isoform ECM1b may be a tumor-suppressor in laryngocarcinoma. Our results demonstrate that TAGET provides a valuable computational toolkit and can be applied to many full-length transcriptome studies.

EMMPRIN expression is associated with metastatic progression in osteosarcoma

Background

Extracellular matrix metalloproteinase inducer (EMMPRIN), a cell-surface glycoprotein, is overexpressed in several cancer types. EMMPRIN induces a metastatic phenotype by triggering the production of matrix metalloproteinase proteins (MMPs) such as MMP1 and MMP2, and vascular endothelial growth factor (VEGF) in cancer cells and the surrounding stromal cells. The purpose of this study was to investigate the expression and role of EMMPRIN in osteosarcoma.

Methods

The level of EMMPRIN expression was evaluated using reverse transcriptase polymerase chain reaction (RT-PCR) in 6 tumor-derived osteosarcoma cell lines and compared with that in normal osteoblasts. To study the prognostic significance of EMMPRIN expression, immunohistochemistry was carried out in prechemotherapy biopsies of 54 patients. siRNA knockdown of EMMPRIN in SaOS-2 cells was conducted to explore the role of EMMPRIN. To study the role of EMMPRIN in tumor-stromal interaction in MMP production and invasion, co-culture of SaOS-2 cells with osteoblasts and fibroblasts was performed. Osteosarcoma 143B cells were injected into the tail vein of BALB/c mice and lung metastasis was analyzed.

Results

EMMRIN mRNA expression was significantly higher in 5 of 6 (83%) tumor-derived cells than in MG63 cells. 90% of specimens (50/54) stained positive for EMMPRIN by immunohistochemistry, and higher expression of EMMPRIN was associated with shorter metastasis-free survival (p = 0.023). Co-culture of SaOS-2 with osteoblasts resulted in increased production of pro-MMP2 and VEGF expression, which was inhibited by EMMPRIN-targeting siRNA. siRNA knockdown of EMMPRIN resulted in decreased invasion. EMMPRIN shRNA-transfected 143B cells showed decreased lung metastasis in vivo.

Conclusions

Our data suggest that EMMPRIN acts as a mediator of osteosarcoma metastasis by regulating MMP and VEGF production in cancer cells as well as stromal cells. EMMPRIN could serve as a therapeutic target in osteosarcoma.

CD147 Is a Promising Target of Tumor Progression and a Prognostic Biomarker

Microenvironment plays a crucial role in tumor development and progression. Cancer cells modulate the tumor microenvironment, which also contribute to resistance to therapy. Identifying biomarkers involved in tumorigenesis and cancer progression represents a great challenge for cancer diagnosis and therapeutic strategy development. CD147 is a glycoprotein involved in the regulation of the tumor microenvironment and cancer progression by several mechanisms—in particular, by the control of glycolysis and also by its well-known ability to induce proteinases leading to matrix degradation, tumor cell invasion, metastasis and angiogenesis. Accumulating evidence has demonstrated the role of CD147 expression in tumor progression and prognosis, suggesting it as a relevant tumor biomarker for cancer diagnosis and prognosis, as well as validating its potential as a promising therapeutic target in cancers.

CD147 and Prostate Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Prostate cancer is one of the most common non-cutaneous malignancies in men. We aimed to systemically evaluate the relationship between the expression of CD147 in tissues and the clinicopathological features of prostate cancer.

METHODS AND FINDINGS

PubMed (1966-2016), EMBASE (1980-2016), the Cochrane Library (1996-2016), Web of Science (1945-2016), China National Knowledge Infrastructure (1982-2016), and the WanFang databases (1988-2016) were searched. Literature quality assessment was performed with the Newcastle-Ottawa Scale. Meta-analysis was performed by using Review Manager 5.3 and Stata 13.0. A total of 12591 prostate cancer patients from 14 studies were included. The results of the meta-analysis showed that there were significant differences in the positive expression rate in the following comparisons: prostatic cancer tissues vs. normal prostate tissues (odds ratio [OR] = 26.93, 95% confidence interval [CI] 7.95-91.20, P < 0.00001), prostatic cancer tissues vs. benign prostatic hyperplasia tissues (OR = 20.54, 95% CI 8.20-51.44, P < 0.00001), high Gleason score vs. low Gleason score (OR = 2.39, 95% CI 1.33-4.27, P = 0.03), TNM III to IV vs. TNM I to II (OR = 9.95, 95% CI 4.96-19.96, P < 0.00001), low or moderate differentiation vs. high differentiation (OR = 8.12, 95% CI 3.69-17.85, P < 0.00001), lymph node metastasis vs. non-lymph node metastasis (OR = 4.31, 95% CI 1.11-16.71, P = 0.03), and distant metastasis vs. non-distant metastasis (OR = 8.90, 95% CI 3.24-24.42, P < 0.00001).

CONCLUSION

The CD147 positive expression rate was closely related to the clinical characteristics of prostate cancer, but more research is needed to confirm the findings owing to the results of the subgroups.

The role of CD147 expression in prostate cancer: a systematic review and meta-analysis

BACKGROUND

There are a number of studies which show that expression of CD147 is increased significantly in prostate cancer (PCa). However, conflicting conclusions have also been reported by other researchers lately. In order to arrive at a clear conclusion, a meta-analysis of eligible studies was conducted.

MATERIALS AND METHODS

We searched PubMed, MEDLINE, Cochrane Library, and the China National Knowledge Infrastructure databases to identify all the published case-control studies on the relationship between the expression of CD147 and PCa until February 2016. In the end, a total of 930 patients in eight studies were included in the meta-analysis.

RESULTS

CD147 expression in the PCa patients increased significantly (odds ratio [OR], 4.65; 95% confidence interval [CI], 3.52-6.14; Z=10.79; P<0.05), but there was obvious heterogeneity between studies (I (2)=92.9%, P<0.05). Subgroup analysis showed that positive expression of CD147 was associated with PCa among the Asian population (OR, 21.01; 95% CI, 12.88-34.28; Z=12.19; P<0.05). Furthermore, it was significantly related to TNM stage (OR, 0.24; 95% CI, 0.17-0.35; Z=7.74; P<0.05), Gleason score (OR, 0.41; 95% CI, 0.31-0.56; Z=5.62; P<0.05), differentiation grade (OR, 0.27; 95% CI, 0.13-0.56; Z=3.47; P<0.05), and pretreatment serum prostate-specific antigen level (OR, 0.07; 95% CI, 0.03-0.16; Z=6.47; P<0.05).

CONCLUSION

Positive expression of CD147 was related to PCa, significant heterogeneity was not found between Asian studies, and the result became more significant. The positive expression of CD147 was significantly related to the clinicopathological characteristics of PCa. This suggests that CD147 plays an essential role in poor prognosis and recurrence prediction.

EMMPRIN/CD147 is an independent prognostic biomarker in cutaneous melanoma

CD147 has been implicated in melanoma invasion and metastasis mainly through increasing metalloproteinase synthesis and regulating VEGF/VEGFR signalling. In this study, the prognostic value of CD147 expression was investigated in a cohort of 196 cutaneous melanomas including 136 consecutive primary malignant melanomas, 30 lymph nodes, 16 in-transit and 14 visceral metastases. A series of 10 normal skin, 10 blue nevi and 10 dermal nevi was used as control. CD147 expression was assessed by immunohistochemistry, and the association of its expression with the clinicopathological characteristics of patients and survival was evaluated using univariate and multivariate statistical analyses. Univariate analysis showed that high CD147 expression was significantly associated with metastatic potential and with a reduced overall survival (P < 0.05 for both) in primary melanoma patients. CD147 expression level was correlated with histological factors which were associated with prognosis: Clark level, ulceration status and more particularly with Breslow index (r = 0.7, P < 10(-8) ). Multivariate analysis retained CD147 expression level and ulceration status as predicting factors for metastasis and overall survival (P < 0.05 for both). CD147 emerges as an important factor in the aggressive behaviour of melanoma and deserves further evaluation as an independent prognostic biomarker.

Aberrant hypomethylation-mediated CD147 overexpression promotes aggressive tumor progression in human prostate cancer

Our previous study revealed the potential role of CD147 in human prostate cancer (PCa). Here, we investigated the CD147 promoter methylation status and the correlation with tumorigenicity in human PCa. CD147 mRNA and protein expression levels were both significantly higher in the 4 PCa cell lines, than in the 2 non-tumorigenic benign human prostatic epithelial cell lines (all P<0.01). We showed hypomethylation of promoter regions of CD147 in PCa cell lines with significant CD147 expression as compared to non-tumorigenic benign human prostatic epithelial cell lines slowly expressing CD147. Additionally, the treatment of methylated cell lines with 5-aza-2'-deoxycytidine increased CD147 expression significantly in low-expressing cell lines and also activated the expression of matrix metalloproteinase (MMP)-2, which may be one of the most important downstream targets of CD147. Furthermore, PCa tissues displayed decreased DNA methylation in the promoter region of CD147 compared to the corresponding non-cancerous prostate tissues, and methylation intensity correlated inversely with the CD147 mRNA levels. There was a significant negative correlation between CD147 mRNA levels and the number of methylated sites in PCa tissues (r=-0.467, P<0.01). In conclusion, our data offer convincing evidence for the first time that the DNA promoter hypomethylation of CD147 may be one of the regulatory mechanisms involved in the cancer-related overexpression of CD147 and may play a crucial role in the tumorigenesis of PCa.

Levels of vascular endothelial growth factor and matrix metalloproteinase-9 proteins in patients with glioma

OBJECTIVE

To investigate the levels of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) proteins in patients with glioma, in order to determine if either protein has prognostic value.

METHOD

The presence of VEGF and MMP-9 proteins in paraffin-embedded tumour specimens from patients with glioma was detected using immunohistochemistry. The correlation between the levels of VEGF and MMP-9 proteins and tumour grade was analysed.

RESULTS

A total of 32 patients with low-grade gliomas (World Health Organization [WHO] grade II) and 48 patients with high-grade gliomas (WHO grades III-IV) participated in the study. Positive immunohistochemical staining of VEGF and MMP-9 proteins was detected in 58/80 (72.5%) and 60/80 (75.0%) of patients, respectively. The level of VEGF immunostaining was significantly positively correlated with the level of MMP-9 immunostaining (r = 0.78). Significantly more high-grade gliomas (grades III-IV) demonstrated positive VEGF and MMP-9 immunostaining compared with the low grade gliomas (grades I-II).

CONCLUSIONS

These data suggest that VEGF and MMP-9 play an important role in the malignant behaviour of gliomas.

Renal cell neoplasias: reversion-inducing cysteine-rich protein with Kazal motifs discriminates tumor subtypes, while extracellular matrix metalloproteinase inducer indicates prognosis

Background

Matrix metalloproteinases can promote invasion and metastasis, which are very frequent in renal cell carcinoma even at the time of diagnosis. Knowing the reversion-inducing cysteine-rich protein with Kazal motifs (RECK) as an inhibitor of matrix metalloproteinases and the extracellular matrix metalloproteinase inducer (EMMPRIN) protein as inducer, we aimed to determine their expression, localization and possible antagonistic action in the pathogenesis and progression of renal cell tumors in a retrospective study.

Methods

Tumor and adjacent normal tissues of 395 nephrectomized patients were immunostained for RECK and EMMPRIN on a tissue microarray.

Results

RECK strongly decreased in renal cell carcinoma compared to normal counterparts (Wilcoxon signed rank test, P < 0.001), and it discriminated tumor entities showing the highest expression in oncocytomas. EMMPRIN, however, could be significantly correlated to pT stage and Fuhrman grading (Spearman’s correlation coefficient r_s = 0.289 and r_s = 0.382, respectively). Higher expression of EMMPRIN was associated with decreased overall survival in Kaplan-Meier analysis (P < 0.001), and the EMMPRIN level could independently predict survival for cases without metastasis and involvement of lymph nodes. Decreased RECK expression was confirmed by Western blotting in tissue of eight normal/tumor matches of patients after radical nephrectomy, whereas the EMMPRIN pattern appeared to be heterogeneous.

Conclusions

We propose RECK down regulation in renal cell carcinoma to be an early event that facilitates tumor formation and progression. EMMPRIN, however, as a prognostic tumor marker, increases only when aggressiveness is proceeding and could add an additional step to invasive properties of renal cell carcinoma.

Reduced CD147 expression is linked to ERG fusion-positive prostate cancers but lacks substantial impact on PSA recurrence in patients treated by radical prostatectomy

The extracellular matrix metalloproteinase inducer CD147 has been suggested as a prognostic marker in prostate cancer. CD147 expression was analyzed by immunohistochemistry on a tissue microarray containing 11,152 prostate cancer specimens. Results were compared to tumor phenotype, biochemical recurrence, ERG status and deletions on PTEN, 3p13, 6q15 and 5q21. CD147 expression was strong in benign prostatic glands and often reduced in prostate cancers. CD147 immunostaining was found in 71.7% of 7628 interpretable cases. CD147 staining was considered strong in 34.6%, moderate in 24.3% and weak in 12.8% of cancers while 28.3% did not show any CD147 reactivity. Reduced CD147 staining was strongly associated with both TMPRSS2-ERG-rearrangement and ERG expression (p<0.0001 each). Within the subgroups of ERG positive and negative cancers, deletions of PTEN, 3p13, 6q15 and 5q21 were unrelated to the CD147 expression status. Decreased CD147 expression was significantly linked to high preoperative PSA values, high Gleason grade, advanced tumor stage (p<0.0001 each), and positive lymph node involvement (p=0.0026) in all cancers. There was a marginal, but statistically significant, association of reduced CD147 expression with early biochemical recurrence (p=0.0296). The significant reduction of CD147 expression in ERG positive prostate cancer provides further evidence for marked biological differences between "fusion type" and "non-fusion type" prostate cancer. Despite a weak association with PSA recurrence, CD147 cannot be considered a relevant prognostic biomarker.

Expression and clinical significance of extracellular matrix metalloproteinase inducer, EMMPRIN/CD147, in human osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. Recent studies have shown that extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) promotes adhesion, invasion and metastasis of malignant tumor cells. The aim of this study was to investigate the impact of EMMPRIN/CD147 expression on prognosis and its correlation with clinicopathological characteristics in patients with osteosarcoma. The expression of EMMPRIN/CD147 in 55 surgical specimens from patients with osteosarcoma at stage IIA or above, 15 non-tumor rib bone tissues, three human osteosarcoma cell lines (Saos-2, U-2OS and MG-63), the human osteoblast cell line HOB and the malignant melanoma cell line A375 were examined by immunohistochemistry, western blot analysis and ELISA, respectively. The potential association of the levels of EMMPRIN/CD147 expression in osteosarcoma specimens with the overall survival of patients was statistically analyzed. We found that the EMMPRIN/CD147 was expressed in 45 out of 55 osteosarcomas, with immunoreactivity primarily within the membrane and cytoplasm of tumor cells, but not in the non-tumor bone tissues. We also observed that EMMPRIN/CD147 was expressed in Saos-2, U-2OS, MG-63 and A375, but not in HOB cells. The levels of EMMPRIN/CD147 expression correlated positively with the pathological degree of osteosarcoma and negatively with the survival period of patients with osteosarcoma. The expression of EMMPRIN/CD147 is a potential factor in the development and prognosis of osteosarcoma and may be a novel therapeutic target of human osteosarcoma.

CD147/EMMPRIN: an effective therapeutic target for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is characterized by high resistance to conventional systemic therapies, rapid progression, easy metastasis and frequent recurrence. There is therefore an urgent requirement to develop novel systemic agents which specifically target hepatoma-associated antigen in the tumors of HCC patients. CD147, a transmembrane glycoprotein, is highly expressed by HCC cells and is strongly associated with HCC progression and prognosis. CD147 in HCC cells modulates HCC growth, promotes invasion and metastasis by stimulating adjacent fibroblasts and HCC cells to produce elevated levels of several extracellular matrix metalloproteinases (MMPs) in the HCC microenvironment. It is also involved in HCC angiogenesis and multidrug resistance (MDR). Clinical progress has been made in HCC treatment using CD147-directed monoclonal antibodies. Here, we give an overview of the literature regarding the molecular features and expression of CD147 in human HCC tissues. We specifically focus on the role of CD147 in HCC invasion and metastasis, as well as in angiogenesis and multidrug resistance. In addition, advances in therapeutic strategies targeting HCC CD147 are summarized.

In vitro and in vivo prostate cancer metastasis and chemoresistance can be modulated by expression of either CD44 or CD147

CD44 and CD147 are associated with cancer metastasis and progression. Our purpose in the study was to investigate the effects of down-regulation of CD44 or CD147 on the metastatic ability of prostate cancer (CaP) cells, their docetaxel (DTX) responsiveness and potential mechanisms involved in vitro and in vivo. CD44 and CD147 were knocked down (KD) in PC-3M-luc CaP cells using short hairpin RNA (shRNA). Expression of CD44, CD147, MRP2 (multi-drug resistance protein-2) and MCT4 (monocarboxylate tranporter-4) was evaluated using immunofluorescence and Western blotting. The DTX dose-response and proliferation was measured by MTT and colony assays, respectively. The invasive potential was assessed using a matrigel chamber assay. Signal transduction proteins in PI3K/Akt and MAPK/Erk pathways were assessed by Western blotting. An in vivo subcutaneous (s.c.) xenograft model was established to assess CaP tumorigenecity, lymph node metastases and DTX response. Our results indicated that KD of CD44 or CD147 decreased MCT4 and MRP2 expression, reduced CaP proliferation and invasive potential and enhanced DTX sensitivity; and KD of CD44 or CD147 down-regulated p-Akt and p-Erk, the main signal modulators associated with cell growth and survival. In vivo, CD44 or CD147-KD PC-3M-luc xenografts displayed suppressed tumor growth with increased DTX responsiveness compared to control xenografts. Both CD44 and CD147 enhance metastatic capacity and chemoresistance of CaP cells, potentially mediated by activation of the PI3K and MAPK pathways. Selective targeting of CD44/CD147 alone or combined with DTX may limit CaP metastasis and increase chemosensitivity, with promise for future CaP treatment.

Comprehensive proteomic analysis of human bile

Bile serves diverse functions from metabolism to transport. In addition to acids and salts, bile is composed of proteins secreted or shed by the hepatobiliary system. Although there have been previous efforts to catalog biliary proteins, an in-depth analysis of the bile proteome has not yet been reported. We carried out fractionation of non-cancerous bile samples using a multipronged approach (SDS-PAGE, SCX and OFFGEL) followed by MS analysis on an LTQ-Orbitrap Velos mass spectrometer using high resolution at both MS and MS/MS levels. We identified 2552 proteins - the largest number of proteins reported in human bile till date. To our knowledge, there are no previous studies employing high-resolution MS reporting a more detailed catalog of any body fluid proteome in a single study. We propose that extensive fractionation coupled to high-resolution MS can be used as a standard methodology for in-depth characterization of any body fluid. This catalog should serve as a baseline for the future studies aimed at discovering biomarkers from bile in gallbladder, hepatic, and biliary cancers.

VEGF and EMMPRIN expression correlates with survival of patients with osteosarcoma

AIM

To investigate the clinicopathologic characteristics of Vascular Endothelial Growth Factor (VEGF) and Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) expression in osteosarcoma, and to evaluate the clinical significance of these two markers in the survival of osteosarcoma.

METHODS

VEGF and EMMPRIN expression in paraffin-embedded specimens gathered from 65 patients with primary osteosarcoma were detected by the method of immunohistochemistry using antibodies against VEGF and EMMPRIN. The correlation of VEGF and EMMPRIN expression with the clinicopathologic features and with the survival of osteosarcoma was subsequently assessed.

RESULTS

The expression of VEGF and EMMPRIN was detected in 47/65 (72.31%) and 45/65 (69.23%) of patients with osteosarcoma, respectively. Positive expression of VEGF and EMMPRIN was significantly correlated with surgical stage and percentage of dead cells of osteosarcoma. A significant correlation was found between the expression of VEGF and EMMPRIN in osteosarcoma (r=0.89, p=0.01). Additionally, surgical stage, percentage of dead cells, VEGF and EMMPRIN expression showed significant influence on overall survival (OS) and disease-free survival (DFS) in univariate analysis. In multivariate analysis, surgical stage (IIA versus IIB/III) and percentage of dead cells (≤90% versus >90%) were significant for DFS and OS. Those patients with VEGF+/EMMPRIN+ co-expression showed significantly shorter OS and DFS compared with VEGF-/EMMPRIN- expression.

CONCLUSION

According to our study, the overexpression of VEGF or EMMPRIN may be an important feature of osteosarcoma. A combined detection of VEGF/EMMPRIN co-expression may benefit us in prediction of a poor survival of osteosarcoma.

Monocarboxylate transporter 4 (MCT4) and CD147 overexpression is associated with poor prognosis in prostate cancer

Background

Monocarboxylate transporters (MCTs) are transmembrane proteins involved in the transport of monocarboxylates across the plasma membrane, which appear to play an important role in solid tumours, however the role of MCTs in prostate cancer is largely unknown. The aim of the present work was to evaluate the clinico-pathological value of monocarboxylate transporters (MCTs) expression, namely MCT1, MCT2 and MCT4, together with CD147 and gp70 as MCT1/4 and MCT2 chaperones, respectively, in prostate carcinoma.

Methods

Prostate tissues were obtained from 171 patients, who performed radical prostatectomy and 14 patients who performed cystoprostatectomy. Samples and clinico-pathological data were retrieved and organized into tissue microarray (TMAs) blocks. Protein expression was evaluated by immunohistochemistry in neoplastic (n = 171), adjacent non-neoplastic tissues (n = 135), PIN lesions (n = 40) and normal prostatic tissue (n = 14). Protein expression was correlated with patients' clinicopathologic characteristics.

Results

In the present study, a significant increase of MCT2 and MCT4 expression in the cytoplasm of tumour cells and a significant decrease in both MCT1 and CD147 expression in prostate tumour cells was observed when compared to normal tissue. All MCT isoforms and CD147 were expressed in PIN lesions. Importantly, for MCT2 and MCT4 the expression levels in PIN lesions were between normal and tumour tissue, which might indicate a role for these MCTs in the malignant transformation. Associations were found between MCT1, MCT4 and CD147 expressions and poor prognosis markers; importantly MCT4 and CD147 overexpression correlated with higher PSA levels, Gleason score and pT stage, as well as with perineural invasion and biochemical recurrence.

Conclusions

Our data provides novel evidence for the involvement of MCTs in prostate cancer. According to our results, we consider that MCT2 should be further explored as tumour marker and both MCT4 and CD147 as markers of poor prognosis in prostate cancer.

Decreased RECK and Increased EMMPRIN expression in urothelial carcinoma of the bladder are associated with tumor aggressiveness

OBJECTIVE

Urothelial bladder carcinomas show a divergent biological behavior, which significantly complicates risk stratification and clinical management. The MMP repressor RECK and the MMP activator EMMPRIN regulate the invasive potential by metalloproteinase-induced stromal degradation. Data on RECK in urothelial bladder cancer are lacking and information on EMMPRIN is sparse. This study aims to investigate the expression of RECK and EMMPRIN in urothelial carcinoma of the bladder and to correlate these findings with clinicopathological parameters.

METHODS

Our study included 127 specimens of urothelial carcinomas derived from 103 patients who underwent either TUR-B or cystectomy. Immunohistochemical expression analysis was performed for RECK, EMMPRIN, MMP-2, MMP-9 and MMP-14. Expression levels were graded for staining intensity and correlated with pT stage and WHO tumor grade.

RESULTS

Invasive (≥pT1) as well as WHO high-grade urothelial carcinomas showed a statistically significant and stepwise downregulation of RECK (p < 0.001) and concomitant upregulation of EMMPRIN (p < 0.001) compared to non-invasive and WHO low-grade tumors. No correlation was observed for the MMPs investigated.

CONCLUSION

Decreased RECK and increased EMMPRIN expression are associated with increasing stage and grade. Both proteins may serve as molecular marker for the distinction between potentially invasive (≥pT1) and non-invasive tumors (≤pTa).

Expression of gangliosides, GD1a, and sialyl paragloboside is regulated by NF-κB-dependent transcriptional control of α2,3-sialyltransferase I, II, and VI in human castration-resistant prostate cancer cells

Gangliosides are sialic acid-containing glycosphingolipids that are associated with tumor malignancy and progression. Among the enzymes required for the production of gangliosides, sialyltransferases have received much attention in terms of their relationship with cancer. In our previous report, ganglioside GD1a and sialyl paragloboside (SPG), a neolacto-series ganglioside, were much more abundant in PC3 and DU145 cells, castration-resistant prostate cancer cells, as compared with hormone-sensitive prostate cancer cells and normal prostate epithelium. GD1a is synthesized from GM1 by α2,3 sialyltransferase (ST3Gal) I and mainly by ST3Gal II. The enzyme to synthesize SPG is ST3Gal VI. The high production of GD1a and SPG in castration-resistant prostate cancer cells was correlated with the high expression of ST3Gal II and VI, respectively. The expression of ST3Gal I and II was mildly induced by phorbol-12-myristate-13-acetate (PMA), and PMA-induced expression of ST3Gal I and ST3Gal II was inhibited by NF-κB decoy oligodeoxynucleotides (ODN) but not by AP-1 decoy ODN. Among the five mammalian homologs of the NF-κB family, RelB RNAi most effectively inhibited the expression of ST3Gal I and ST3Gal II. The expression of ST3Gal VI was also most effectively inhibited by RelB RNAi. The amount of GD1a and SPG was significantly reduced by RelB siRNA treatment in PC3 cells. Thus, the production of GD1a and SPG in castration-resistant prostate cancer cells was indirectly controlled by NF-κB, mainly by RelB, through the transcriptional regulation of ST3Gal I, II, and VI.

Development of an in vitro model to study the impact of BMP-2 on metastasis to bone

Prostate cancer cases and deaths have increased for years, yet the mechanisms involved in prostate cancer metastasis to bone remain poorly understood. To address this need, an effective and relevant in vitro model for the study of prostate cancer bone metastases would be useful. Therefore, a 3D in vitro tissue system was established using prostate cancer cells (PC3), suitable culture conditions and a 3D silk scaffold biomaterial to provide mechanically robust and slow degrading matrices to support the tissues for extended time frames. The role of BMP-2 on the progression of prostate cancer was investigated using this 3D tissue system. The results suggest that BMP-2 stimulates the migration of PC3 cells, suggesting insight into mechanisms involved in this critical step in the disease. The data support the conclusion that this in vitro system mimics aspects of prostate cancer metastasis in the presence of BMP-2, thus the system can be utilized as a starting point as an in vitro model for further studies of prostate cancer development and metastasis, as well as in the screening of new therapeutic treatments.

Co-expression of CD147 (EMMPRIN), CD44v3-10, MDR1 and monocarboxylate transporters is associated with prostate cancer drug resistance and progression

Background:

The aim of this study is to seek an association between markers of metastatic potential, drug resistance-related protein and monocarboxylate transporters in prostate cancer (CaP).

Methods:

We evaluated the expression of invasive markers (CD147, CD44v3-10), drug-resistance protein (MDR1) and monocarboxylate transporters (MCT1 and MCT4) in CaP metastatic cell lines and CaP tissue microarrays (n=140) by immunostaining. The co-expression of CD147 and CD44v3-10 with that of MDR1, MCT1 and MCT4 in CaP cell lines was evaluated using confocal microscopy. The relationship between the expression of CD147 and CD44v3-10 and the sensitivity (IC₅₀) to docetaxel in CaP cell lines was assessed using MTT assay. The relationship between expression of CD44v3-10, MDR1 and MCT4 and various clinicopathological CaP progression parameters was examined.

Results:

CD147 and CD44v3-10 were co-expressed with MDR1, MCT1 and MCT4 in primary and metastatic CaP cells. Both CD147 and CD44v3-10 expression levels were inversely related to docetaxel sensitivity (IC₅₀) in metastatic CaP cell lines. Overexpression of CD44v3-10, MDR1 and MCT4 was found in most primary CaP tissues, and was significantly associated with CaP progression.

Conclusions:

Our results suggest that the overexpression of CD147, CD44v3-10, MDR1 and MCT4 is associated with CaP progression. Expression of both CD147 and CD44v3-10 is correlated with drug resistance during CaP metastasis and could be a useful potential therapeutic target in advanced disease.

CD147 expression in pituitary adenomas and its significance for clinical outcome

CD147, a transmembrane glycoprotein member of the immunoglobulin superfamily of receptors, is involved in invasion and angiogenesis of some types of tumors; but its roles and clinicopathologic significance in pituitary adenomas are not clear. Using immunohistochemistry and quantitative reverse transcriptase polymerase chain reaction, we measured the expression of CD147, matrix metalloproteinase-2, and Ki-67 in 74 pituitary adenomas and evaluated the associations of CD147 with matrix metalloproteinase-2, Ki-67 labeling index, clinicopathologic characteristics, and prognosis. The CD147 protein was expressed in 35 (87.5%) of 40 invasive and in 16 (47.1%) of 34 noninvasive pituitary adenomas; and matrix metalloproteinase-2, in 32 (80.0%) and in 14 (41.2%) of 34, respectively. The Ki-67 labeling index was 3.93% +/- 2.48% for invasive samples and 1.32% +/- 1.04% for noninvasive ones. In addition, the expression of CD147 was positively correlated with matrix metalloproteinase-2, Ki-67 labeling index, or both in invasive pituitary adenomas (P< .01 and P< .01, respectively). All of the 4 recurrent adenomas were concurrently positive for CD147 and matrix metalloproteinase-2, and the Ki-67 labeling indexes of all were greater than 3%. Thus, CD147 may play a pivotal role in the development and progression of invasive pituitary adenomas and also be a useful prognostic biomarker.

Promising tumor-associated antigens for future prostate cancer therapy

Prostate cancer (CaP) is one of the most prevalent malignant diseases among men in Western countries. There is currently no cure for metastatic castrate-resistant CaP, and median survival for these patients is about 18 months; the high mortality rate seen is associated with widespread metastases. Progression of CaP from primary to metastatic disease is associated with several molecular and genetic changes that can affect the expression of specific tumor-associated antigens (TAAs) or receptors on the cell surface. Targeting TAAs is emerging as an area of promise for controlling late-stage and recurrent CaP. Several reviews have summarized the progress made in targeting signaling pathways for CaP but will not be discussed here. We describe some important CaP TAAs. These include prostate stem-cell antigen, prostate-specific membrane antigen, MUC1, epidermal growth factor receptor, platelet-derived growth factor and its receptor, urokinase plasminogen activator and its receptor, and extracellular matrix metalloproteinase inducer. We summarize recent advancements in our understanding of their role in CaP metastasis, as well as potential therapeutic options for targeting CaP TAAs. We also discuss the origin, identification, and characterization of prostate cancer stem cells (CSCs) and the potential benefits of targeting prostate CSCs to overcome chemoresistance and CaP recurrence.

Angiogenesis as a strategic target for prostate cancer therapy

It is becoming increasingly clear that angiogenesis plays a crucial role in prostate cancer (CaP) survival, progression, and metastasis. Tumor angiogenesis is a hallmark of advanced cancers and an attractive treatment target in multiple solid tumors. By understanding the molecular basis of resistance to androgen withdrawal and chemotherapy in CaP, the rational design of targeted therapeutics is possible. This review summarizes the recent advancements that have improved our understanding of the role of angiogenesis in CaP metastasis and the potential therapeutic efficacy of inhibiting angiogenesis in this disease. Current therapeutic options for patients with metastatic hormone-refractory CaP are very limited. Targeting vasculature is a developing area, which shows promise for the control of late stage and recurrent CaP disease and for overcoming drug resistance. We discuss angiogenesis and its postulated mechanisms and focus on the regulation of angiogenesis in CaP progression and the therapeutic beneficial effects associated with targeting of the CaP vasculature to overcome the resistance to current treatments and CaP recurrence.

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.

VEGF inhibitors and prostate cancer therapy

Prostate cancer remains the most common non-cutaneous malignancy among American men. Since the advent of PSA testing, most men are diagnosed with localized disease, but a proportion of men will be diagnosed with metastatic disease, many will eventually receive chemotherapy with docetaxel and prednisone. However, responses are not durable and all men will ultimately progress on this treatment. As such, continued efforts are geared towards the discovery of new agents and mechanisms of targeting prostate cancer. Angiogenesis has been shown to play an important role in tumorigenesis, proliferation and metastasis in prostate cancer. Here we discuss the major angiogenic signaling pathway involving VEGF in prostate cancer progression and the role of various promising agents that targets this pathway. This includes bevacizumab, thalidomide and its analogues, tyrosine kinase inhibitors sorafenib and AZD2171, and other inhibitors of angiogenic signaling pathways. Results of key clinical trials associated with the use of these agents and future directions are discussed herein.

The interaction of HAb18G/CD147 with integrin alpha6beta1 and its implications for the invasion potential of human hepatoma cells

Background

HAb18G/CD147 plays pivotal roles in invasion by hepatoma cells, but the underlying mechanism remains unclear. Our previous study demonstrated that overexpression of HAb18G/CD147 promotes invasion by interacting with integrin α3β1. However, it has never been investigated whether α3β1 is solely responsible for this process or if other integrin family members also interact with HAb18G/CD147 in human hepatoma cells.

Methods

Human SMMC-7721 and FHCC98 cells were cultured and transfected with siRNA fragments against HAb18G/CD147. The expression levels of HAb18G/CD147 and integrin α6β1 were determined by immunofluorescent double-staining and confocal imaging analysis. Co-immunoprecipitation and Western blot analyses were performed to examine the native conformations of HAb18G/CD147 and integrin α6β1. Invasion potential was evaluated with an invasion assay and gelatin zymography.

Results

We found that integrin α6β1 co-localizes and interacts with HAb18G/CD147 in human hepatoma cells. The enhancing effects of HAb18G/CD147 on invasion capacity and secretion of matrix metalloproteinases (MMPs) were partially blocked by integrin α6β1 antibodies (P < 0.01). Wortmannin, a specific phosphatidylinositol kinase (PI3K) inhibitor that reverses the effect of HAb18G/CD147 on the regulation of intracellular Ca²⁺ mobilization, significantly reduced cell invasion potential and secretion of MMPs in human hepatoma cells (P < 0.05). Importantly, no additive effect between Wortmannin and α6β1 antibodies was observed, indicating that α6β1 and PI3K transmit the signal in an upstream-downstream relationship.

Conclusion

These results suggest that α6β1 interacts with HAb18G/CD147 to mediate tumor invasion and metastatic processes through the PI3K pathway.

Clinical implications and prognostic value of EMMPRIN/CD147 and MMP2 expression in pediatric gliomas

Extracellular matrix metalloproteinase inducer (EMMPRIN), a member of the immunoglobulin superfamily, is present on the surface of tumor cells where it stimulates adjacent fibroblasts to produce matrix metalloproteinases (MMPs). We have analyzed the clinicopathological characteristics of EMMPRIN and MMP2 expression in normal brain tissue and pediatric gliomas and evaluated their prognostic value in diagnosing the latter. Immunochemistry analysis revealed EMMPRIN and MMP2 expression in cryo-sections of pediatric gliomas (45 samples) and normal brain tissue (20 samples). Both EMMPRIN and MMP2 were expressed in normal brain and glioma tissues with different levels of malignancy. The intensively positive expression rates of EMMPRIN (22/27) and MMP2 (21/27) in anaplastic astrocytoma and glioblastoma tissues were significantly higher than those in normal brain and low-grade astrocytoma tissues (2/28 and (1/2)8, respectively). Spearman analysis indicated that the expression level of EMMPRIN was significantly positively correlated with that of MMP2 (r = 0.86, p < 0.01). The positive expression of EMMPRIN and MMP2 was associated with higher grade gliomas. Patients with EMMPRIN+/MMP2+ expression had the lowest survival rate (p < 0.01). Based on these results, we conclude that EMMPRIN and MMP2 are expressed differently in normal brain and pediatric gliomas. The detection of their co-expression may facilitate the prediction of pediatric gliomas prognosis.

Transporter molecules influence the gene expression in HeLa cells

Progresses in biology and pharmacology led to highly specific bioactive substances, but their poor bioavailability at the site of action is a result of their physico-chemical properties. Various design approaches for transport carrier molecules facilitating the cellular entry of bioactive substances could help to reach their molecular target in cells and tissues. The transfer efficacy and the subsequent pharmacological effects of the cargo molecules are well investigated, but the investigations of effects of the carrier molecules themselves on the target cells or tissues remain necessary. A special attention should be paid to the differential gene expression, particularly in the interpretation of the data achieved by highly specific active pharmaceutical products. After application of transmembrane transport peptides, particularly the pAnt and also the HIV-1 Tat, cells respond with a conspicuous altered gene expression of at least three genes. The PKN1 gene was induced and two genes (ZCD1 and BSG) were slightly repressed. The genes and the chromosomes are described, the moderate differential gene expression graphed, and the ontology is listed.