Upregulated EMMPRIN/CD147 might contribute to growth and angiogenesis of gastric carcinoma: a good marker for local invasion and prognosis

Co-expression of CD147 and GLUT-1 indicates radiation resistance and poor prognosis in cervical squamous cell carcinoma

The aim of this study was to investigate the association of CD147 and GLUT-1, which play important roles in glycolysis in response to radiotherapy and clinical outcomes in patients with locally advanced cervical squamous cell carcinoma (LACSCC). The records of 132 female patients who received primary radiation therapy to treat LACSCC at FIGO stages IB-IVA were retrospectively reviewed. Forty-seven patients with PFS (progression-free survival) of less than 36 months were regarded as radiation-resistant. Eighty-five patients with PFS longer than 36 months were regarded as radiation-sensitive. Using pretreatment paraffin-embedded tissues, we evaluated CD147 and GLUT-1 expression by immunohistochemistry. Overexpression of CD147, GLUT-1, and CD147 and GLUT-1 combined were 44.7%, 52.9% and 36.5%, respectively, in the radiation-sensitive group, and 91.5%, 89.4% and 83.0%, respectively, in the radiation-resistant group. The 5-year progress free survival (PFS) rates in the CD147-low, CD147-high, GLUT-1-low, GLUT-1-high, CD147- and/or GLUT-1-low and CD147- and GLUT-1- dual high expression groups were 66.79%, 87.10%, 52.78%, 85.82%, 55.94%, 82.90% and 50.82%, respectively. CD147 and GLUT-1 co-expression, FIGO stage and tumor diameter were independent poor prognostic factors for patients with LACSCC in multivariate Cox regression analysis. Patients with high expression of CD147 alone, GLUT-1 alone or co-expression of CD147 and GLUT-1 showed greater resistance to radiotherapy and a shorter PFS than those with low expression. In particular, co-expression of CD147 and GLUT-1 can be considered as a negative independent prognostic factor.

Combined inhibition of EMMPRIN and epidermal growth factor receptor prevents the growth and migration of head and neck squamous cell carcinoma cells

It has been reported that the epidermal growth factor receptor (EGFR) expression is associated with the extracellular matrix metalloproteinase inducer (EMMPRIN) in some solid tumors; however, the relationship of EMMPRIN with EGFR in head and neck cancers is not fully understood. To determine the relationship between EMMPRIN and EGFR in head and neck squamous cell carcinoma (HNSCC), HNSCC cells were stimulated with epidermal growth factor (EGF), a ligand of EGFR. EMMPRIN expression in HNSCC cells was upregulated by EGF. In addition, EGF stimulation induced HNSCC cell invasion and MMP-9 expression. This increase in invasion and MMP-9 expression was abrogated by downmodulation of EMMPRIN. Furthermore, to determine the effects of combined EMMPRIN and EGFR targeting in HNSCC, HNSCC cells were treated with an EMMPRIN function-blocking antibody and the EGFR inhibitor AG1478. This combined treatment resulted in greater inhibition of HNSCC cell proliferation and migration compared with the individual agents alone. These results suggest that EMMPRIN mediates EGFR-induced tumorigenicity and that combined targeting of EMMPRIN and EGFR may be an efficacious treatment approach.

[Construction of a CD147 lentiviral expression vector and establishment of its stably transfected A549 cell line]

BACKGROUND AND OBJECTIVE

CD147, a type of transmembrane glycoprotein embedded on the surface of tumor cells, can promote tumor invasion and metastasis. This aim of this study is to construct a CD147 lentiviral expression vector, establish its stably transfected A549 cell line, and observe the effect of CD147 on MMP-9 proliferation as well as on the invasive ability of human lung adenocarcinoma cells.

METHODS

Full-length CD147 gene was amplified by real-time polymerase chain reaction (RT-PCR), inserted into a pEGFP vector to construct pEGFP-CD147 and pEGFP vectors, and then transfected into 293FT cells to precede the lentivirus equipment package. Subsequently, we collected the lentivirus venom to infect the A549 cells and establish a stable, overexpressed cell line named A549-CD147. The mRNA expression of MMP-9 was examined by RT-PCR. The proliferation and invasive ability of the human lung cancer cells before and after transfection were examined by the CCK-8 and Transwell methods.

RESULTS

A CD147 lentiviral expression vector (pEGFP-CD147) was successfully constructed by restrictive enzyme digestion and plasmid sequencing. RT-PCR and Western blot analyses revealed increased mRNA and protein expression of CD147 gene in cells transfected with pEGFP-CD147 compared with the control groups. Therefore, the A549-CD147 cell line was successfully established through the experiment. The mRNA expression of MMP-9 also significantly increased after the upregulation of CD147 expression. Meanwhile, CCK-8 and Transwell assays indicated that the proliferation and invasive ability significantly increased in the A549-CD147 cells.

CONCLUSIONS

A lentiviral CD147 expression vector and its A549 cell line (A549-CD14) were successfully constructed. CD147 overexpression upregulated the protein expression of MMP-9, and strengthened the proliferation and invasive ability of human lung adenocarcinoma cells.

EMMPRIN promotes angiogenesis, proliferation, invasion and resistance to sunitinib in renal cell carcinoma, and its level predicts patient outcome

PURPOSE

Extracellular matrix metalloproteinase inducer (EMMPRIN) has been reported to play crucial roles, including in angiogenesis, in several carcinomas. However, the correlation between EMMPRIN levels and angiogenesis expression profile has not been reported, and the role of EMMPRIN in renal cell carcinoma (RCC) is unclear. In the present study, we evaluated the association of EMMPRIN with angiogenesis, its value in prognosis, and its roles in RCC.

EXPERIMENTAL DESIGN

EMMPRIN expression was examined in 50 RCC patients treated with radical nephrectomy. Angiogenesis, proliferation, and invasion activity were evaluated using EMMPRIN knockdown RCC cell lines. The size of EMMPRIN-overexpressing xenografts was measured and the degree of angiogenesis was quantified. EMMPRIN expression was evaluated in RCC patients who received sunitinib therapy and in sunitinib-resistant cells. Further, the relation between EMMPRIN expression and sensitivity to sunitinib was examined.

RESULTS

EMMPRIN score was significantly associated with clinicopathological parameters in RCC patients, as well as being significantly correlated with microvessel area (MVA) in immature vessels and with prognosis. Down-regulation of EMMPRIN by siRNA led to decreased VEGF and bFGF expression, cell proliferation, and invasive potential. EMMPRIN over-expressing xenografts showed accelerated growth and MVA of immature vessels. EMMPRIN expression was significantly increased in patients who received sunitinib therapy as well as in sunitinib-resistant 786-O cells (786-suni). EMMPRIN-overexpressing RCC cells were resistant to sunitinib.

CONCLUSION

Our findings indicate that high expression of EMMPRIN in RCC plays important roles in tumor progression and sunitinib resistance. Therefore, EMMPRIN could be a novel target for the treatment of RCC.

Propranolol induces apoptosis of human umbilical vein endothelial cells through downregulation of CD147

BACKGROUND

Infantile haemangiomas (IHs) are benign tumours in infancy. Most patients suffering from IHs do not require treatment. However, if there is a dramatic aesthetic or functional impairment, treatment is needed. Currently the most promising therapy for complicated IHs is the oral administration of propranolol, but its mechanism is unclear.

OBJECTIVES

To investigate the role of CD147 in propranolol-induced apoptosis in human umbilical vein endothelial cells (HUVECs).

METHODS

Human umbilical vein endothelial cells were treated with propranolol, and the treatment effects were investigated through the following methodology. (i) Cell proliferation and apoptosis were detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis. (ii) The expression level of CD147 was measured by reverse-transcription polymerase chain reaction and Western blotting. (iii) HUVECs were transfected with lentivirus encoding CD147 short hairpin (sh)RNA or CD147 cDNA. Ensuing changes in cell proliferation and apoptosis after transfection were measured using the MTT assay and flow cytometry. (iv) The level of phosphorylation of Bcl-2-associated death promoter (BAD) at Ser112 in HUVECs after propranolol treatment and/or CD147 shRNA transfection was detected by Western blotting.

RESULTS

Propranolol inhibited cell proliferation and induced apoptosis in HUVECs. It decreased CD147 protein expression in a concentration-dependent manner. Knocking down CD147 not only induced apoptosis but also exacerbated the apoptosis triggered by propranolol in HUVECs. Overexpression of CD147 can protect HUVECs from apoptosis and propranolol-induced apoptosis. Furthermore, knockdown of both propranolol and CD147 can downregulate Ser112 phosphorylation of BAD, indicating that propranolol and CD147 induce apoptosis in HUVECs through the same signalling transduction pathway.

CONCLUSIONS

Our studies demonstrate that propranolol-induced apoptosis may be mediated through the downregulation of CD147 in HUVECs. This study highlights a novel step in propranolol action and suggests a potential new target for the treatment of IHs.

The role of EMMPRIN expression in ovarian epithelial carcinomas

Purpose: Extracellular matrix metalloproteinase inducer (EMMPRIN) was reported to involve in the invasion and metastasis of malignancies by regulating the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) in stromal and cancer cells. The study aimed to clarify the role of EMMPRIN expression in tumorigenesis and progression of ovarian epithelial carcinomas.

Methods: EMMPRIN siRNA were transfected into ovarian carcinoma cells with the phenotypes and their related molecules examined. EMMPRIN expression was determined in ovarian normal tissue, benign and borderline tumors, and epithelial carcinomas by real-time PCR, western blot, and immunohistochemisty.

Results: EMMPRIN siRNA treatment resulted in a lower growth, G₁ arrest, apoptotic induction, decreased migration, and invasion. The transfectants showed reduced expression of Wnt5a, Akt, p70s6k, Bcl-xL, survivin, VEGF, and MMP-9 than mock and control cells at both mRNA and protein levels. According to real-time PCR and western blot, EMMPRIN mRNA or protein level was higher in ovarian borderline tumor and carcinoma than normal ovary and benign tumors (P < 0.05), and positively correlated with dedifferentiation and FIGO staging (P < 0.05). Immuhistochemically, EMMPRIN expression was positively correlated with FIGO staging, dedifferentiation, Ki-67 expression, the lower cumulative and relapse-free survival rate (P < 0.05).

Conclusions: Upregulated expression of EMMPRIN protein and mRNA might be involved in the pathogenesis, differentiation, and progression of ovarian carcinomas, possibly by modulating cellular events, such as proliferation, cell cycle, apoptosis, migration, and invasion.

Epithelial expression of extracellular matrix metalloproteinase inducer/CD147 and matrix metalloproteinase-2 in neoplasms and precursor lesions derived from cutaneous squamous cells: An immunohistochemical study

Extracellular matrix metalloproteinase inducer (CD147) is a transmembrane glycoprotein involved in the regulation of matrix metalloproteinases (MMPs). The study investigated CD147 and MMP-2 expression in epidermis of cutaneous squamous lesions. CD147 and MMP-2 expressions were evaluated immunohistochemically in 44 specimens: 18 actinic keratoses (AK), 6 squamous cell carcinomas in situ (SCCIS), 13 squamous cell carcinomas (SCC; peritumoral and invasive portions assessed), and 7 normal skins. Patterns of expression were assessed, with MMP-2 in nuclei (MMP-2n) and cytoplasm (MMP-2c) evaluated separately. The expression of each marker was quantified using a calculated immunohistochemical/histologic score (H-score). Correlations were analyzed for the marker H-scores in each study group. Associations between H-scores and histopathologic parameters were also evaluated. CD147 H-score was the highest in SCC (invasive islands), followed by AK, SCCIS, and control specimens, respectively. MMP-2n and MMP-2c H-scores were the highest in AK, followed by SCCIS, SCC, and control specimens, respectively. MMP-2c and MMP-2n H-scores were significantly higher in peritumoral epidermis than in invasive islands of SCC. MMP-2c and CD147 H-scores were positively correlated in the peritumoral SCCs. CD147 H-score was positively correlated with tumor differentiation in SCC. The findings suggest that overexpression of CD147 plays a role in the development of SCC.

ERK1/2 signalling pathway is involved in CD147-mediated gastric cancer cell line SGC7901 proliferation and invasion

This study aimed to investigate the role of CD147 in the progression of gastric cancer and the signalling pathway involved in CD147-mediated gastric cancer cell line SGC7901 proliferation and invasion. Short hairpin RNA (shRNA) expression vectors targeting CD147 were constructed to silence CD147, and the expression of CD147 was monitored by quantitative realtime reverse transcriptase polymerase chain reaction and Western blot and further confirmed by immunohistochemistry in vivo. Cell proliferation was determined by Cell Counting Kit-8 assay, the activities of matrix metalloproteinase (MMP)-2 and MMP-9 were determined by gelatin zymography, and the invasion of SGC7901 was determined by invasion assay. The phosphorylation and non-phosphorylation of the mitogen-activated protein kinases, extracellular signal-regulated kinase1/2 (ERK1/2), P38 and c-Jun NH2-terminal kinase were examined by Western blot. Additionally, the ERK1/2 inhibitor U0126 were used to confirm the signalling pathway involved in CD147-mediated SGC7901 progression. The BALB/c nude mice were used to study tumour progression in vivo. The results revealed that CD147 silencing inhibited the proliferation and invasion of SGC7901 cells, and down-regulated the activities of MMP-2 and MMP-9 and the phosphorylation of the ERK1/2 in SGC7901 cells. ERK1/2 inhibitor U0126 decreased the proliferation, and invasion of SGC7901 cells, and down-regulated the MMP-2 and MMP-9 activities. In a nude mouse model of subcutaneous xenografts, the tumour volume was significantly smaller in the SGC7901/shRNA group compared to the SGC7901 and SGC7901/snc-RNA group. Immunohistochemistry analysis showed that CD147 and p-ERK1/2 protein expressions were down-regulated in the SGC7901/shRNA2 group compared to the SGC7901 and SGC7901/snc-RNA group. These results suggest that ERK1/2 pathway involves in CD147-mediated gastric cancer growth and invasion. These findings further highlight the importance of CD147 in cancer progression, indicating that CD147 would be an attractive therapeutic target for gastric cancer.

Expression of HAb18G/CD147 and its localization correlate with the progression and poor prognosis of non-small cell lung cancer

This study was designed to investigate the association of HAb18G/CD147 expression and localization with clinicopathological parameters and prognosis in NSCLC. Two hundred and eight (208) specimens of surgically resected NSCLC were stained by immunohistochemistry utilizing mouse anti-human HAb18G/CD147 monoclonal antibody. High levels of HAb18G/CD147 expression were associated with male gender, smoking history, tumor position, distant metastasis status, and clinical stage (p<0.05) in squamous cell carcinoma. In adenocarcinomas, HAb18G/CD147 expression was associated with male gender, tumor diameter, differentiation, lymph node status, distant metastasis status, and clinical stage (p<0.05). HAb18G/CD147 expression with higher PU was predominantly localized in the tumor cell membranes rather than in cytoplasms. In squamous cell carcinomas, membranous localization of HAb18G/CD147 was linked to distant metastasis status and TNM stage (p<0.05). Cytoplasmic localization of HAb18G/CD147 was associated with male gender and smoking history. In adenocarcinomas, membranous localization of HAb18G/CD147 correlated with tumor diameter, differentiation and distant metastasis (p<0.05). Univariate analysis indicated that patients with high HAb18G/CD147 expression and membranous localization predicted poor prognosis in both squamous cell carcinomas and adenocarcinomas. Multivariate analysis showed that lymph node status (HR=1.762, 95%CI 1.105-2.811, p=0.017), distant metastasis status (HR=3.789, 95%CI 2.196-6.539, p=0.000), expression (HR=6.632, 95%CI 2.457-17.904, p=0.000), and localization (HR=0.520, 95%CI 0.341-0.794, p=0.002) were good or excellent independent predictors of patient survival. HAb18G/CD147 is a biomarker characterizing progression and survival of NSCLC. More importantly, its cellular localizations should be considered in the analysis of clinicopathological characteristics and prognostic factors in NSCLC.

Matrix metalloproteinase-9 as a prognostic factor in gastric cancer: a meta-analysis

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is associated with disruption of basement membranes of blood vessels and promotion of metastasis through the lymphatics. However, its prognostic value for survival in patients with gastric cancer remains controversial.

METHOD

We therefore conducted a meta-analysis of the published literature in order to clarify the impact of MMP-9. Clinical studies were selected for further analysis if they provided an independent assessment of MMP-9 in gastric cancer and reported analysis of survival data according to MMP-9 expression.

RESULTS

A total of 11 studies, covering 1700 patients, were included for meta- analysis. A summary hazard ratio (HR) of all studies and sub-group hazard ratios were calculated. The combined HR suggested that a positive MMP-9 expression had an impact on overall survival: 1.25 (95% confidence interval 1.11-1.40) in all eligible studies; 1.13 (1.06-1.20) in 8 studies detecting MMP-9 by immunohistochemistry; 1.36 (1.12-1.65) in 7 studies from Asia. Only one study for DFS showed a significant impact on disease free survival (HR 1.73, 95%CI 1.27-2.34).

CONCLUSIONS

Our findings suggested that MMP-9 protein expression might be a factor for a poor prognosis in patients with gastric cancer. However, the association was rather weak, so that more prospective studies should further explore the prognostic impact of MMP-9 mRNA and correlations between MMP-9 and clinicopathological characteristics.

Upregulated expression of ADAM17 is a prognostic marker for patients with gastric cancer

OBJECTIVE

This study was designed to evaluate the expression and prognostic significance of A Disintegrin and Metalloproteinase17 (ADAM17) protein in patients with gastric cancer.

BACKGROUND

Tumor invasion and metastasis are primary causes for treatment failure or death among cancer patients. ADAM17 is a multidomain transmembrane glycoprotein involved in the release of several ligands that were shown to promote tumor formation and progression. Elevated expression of ADAM17 was detected in a number of human cancers and was associated with poor progression and prognosis of the diseases. In gastric cancer, however, the expression and prognostic significance of ADAM17 has not been fully elucidated.

METHODS

The expressions of ADAM17 and extracellular matrix metalloproteinase inducer (EMMPRIN), a protein implicated in tumor invasion and metastasis, were detected using the tissue microarray technique and immunohistochemical EnVision method and compared with clinicopathological parameters of patients with gastric cancer.

RESULTS

The expressions of ADAM17 and EMMPRIN were upregulated in gastric cancer lesions compared with their expressions in adjacent non-cancerous tissues (P < 0.01). High expression of ADAM17 was detected in 35.78% (156/436) of patients with gastric cancer and positively correlated with the expression of EMMPRIN (r = 0.738, P < 0.01). ADAM17 expression was associated with a number of clinicopathological parameters including depth of invasion and TNM stage of the tumor (P < 0.05). In each TNM stage, patients with high ADAM17 expression had a longer mean survival time than those with low expression (P < 0.05). Particularly, the mean survival time of stage II gastric cancer patients with low ADAM17 expression was longer than that of stage I patients with high ADAM17 expression (P < 0.01). Multivariate survival analysis suggested that, along with other parameters, ADAM17 and EMMPRIN expression were independent prognostic factors for patients with gastric cancer.

CONCLUSIONS

ADAM17 was implicated in the progression of gastric cancer. On the basis of the TNM stage, detection of ADAM17 expression will be helpful for predicting prognosis of gastric cancer.

Beclin 1 expression is an independent prognostic factor for gastric carcinomas

Beclin 1, an important autophagy-related protein in human cells, is involved in autophagy, differentiation, anti-apoptosis, and cancer progression, which is increased during periods of cell stress and extinguished during the cell cycle. In order to clarify the role of Beclin 1 in gastric carcinogenesis and subsequent progression, its expression was examined by immunohistochemistry and in situ hybridization (ISH) on tissue microarrays containing gastric carcinomas, adjacent non-neoplastic mucosa, and metastatic lymph node. Gastric carcinoma tissue and cell lines were studied for Beclin 1 expression by Western blot or RT-PCR, respectively. The results demonstrated that Beclin 1 was distinctively expressed in GES-1, AGS, BGC-823, GT-3 TKB, HGC-27, KATO-III, MGC-803, MKN28, MKN45, SCH, SGC-7901, or STKM-2 at both mRNA and protein levels. However, Beclin 1 mRNA was highly expressed in gastric carcinoma than matched mucosa by real-time PCR and ISH (P < 0.05). Beclin 1 expression was negatively related to distant metastasis and poor prognosis of gastric carcinoma (P < 0.05). Beclin 1 was highly expressed in male than female patients with gastric carcinoma (P < 0.05). The 65-year-elder patients with gastric carcinoma had higher Beclin 1 expression than the younger ones (P < 0.05). The diffuse-type carcinomas showed less Beclin 1 expression than intestinal- and mixed-type ones (P < 0.05). In intestinal-type gastric carcinoma, Beclin 1 expression was inversely associated with venous invasion, lymph node metastasis, and tumor-node-metastasis (TNM) staging (P < 0.05). Kaplan-Meier analysis indicated that Beclin 1 expression was positively linked to favorable prognosis of the patients with overall and intestinal-type carcinoma (P < 0.05). Cox's proportional hazard model indicated that venous invasion, lymph node metastasis, distant metastasis, TNM staging, and Beclin 1 expression were independent prognostic factors for gastric carcinomas (P < 0.05). It was suggested that aberrant Beclin 1 expression is closely linked to pathogenesis, metastasis, and differentiation of gastric carcinoma. Beclin 1 expression might be employed to indicate the favorable prognosis of gastric carcinomas as an independent factor.

Extracellular matrix metalloproteinase inducer is associated with severity of brain oedema following experimental subarachnoid haemorrhage in rats

OBJECTIVE

Brain oedema is a major cause of clinical deterioration and death following brain trauma; cellular mechanisms involved in its development remain elusive. This study investigated the role of extracellular matrix metalloproteinase inducer (EMMPRIN) in brain oedema.

METHODS

The monofilament puncture model was used to induce subarachnoid haemorrhage. Adult male Sprague-Dawley rats were divided into five groups (n = 20 per group): sham-operated, sacrificed immediately after surgery (sham group); sacrificed 12, 24 or 72 h after subarachnoid haemorrhage induction (SAH-12, SAH-24 and SAH-72 groups, respectively); treated with EMMPRIN inhibitor immediately after subarachnoid haemorrhage, sacrificed at 24 h (SAH-inhibition group). Mean brain water content, and EMMPRIN mRNA and protein levels, were determined.

RESULTS

Compared with the sham group, mean brain water content, EMMPRIN mRNA and protein levels in the SAH-12, SAH-24 and SAH-72 groups increased rapidly and significantly (maximal at 24 h). EMMPRIN inhibition significantly reduced mean brain water content and EMMPRIN mRNA and protein levels in the SAH-inhibition group, compared with the SAH-24 group.

CONCLUSIONS

EMMPRIN upregulation may be important in the formation of brain oedema; inhibition of EMMPRIN activity may provide a potential approach to reduce oedema after subarachnoid haemorrhage.

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.

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.

(18)F-FDG PET/CT imaging detects therapy efficacy of anti-EMMPRIN antibody and gemcitabine in orthotopic pancreatic tumor xenografts

PURPOSE

The objective of this study is to evaluate the therapeutic response to a novel monoclonal antibody targeting human extracellular matrix metalloproteinase inducer (EMMPRIN) in combination with gemcitabine in a pancreatic-tumor xenograft murine model by sequential 2-deoxy-2-[18F]fluoro-D-glucose ((18)F-FDG) positron emission tomography/computed tomgraphy (PET/CT) imaging.

PROCEDURES

Four groups of SCID mice bearing orthotopic pancreatic tumor xenografts were injected with phosphate-buffered saline, gemcitabine (120 mg/kg BW), anti-EMMPRIN antibody (0.2 mg), or combination, respectively, twice weekly for 2 weeks, while (18)F-FDG PET/CT imaging was performed weekly for 3 weeks. Changes in mean standardized uptake value (SUV(mean)) of (18)F-FDG and volume of tumors were determined.

RESULTS

The tumor SUV(mean) change in the group receiving combination therapy was significantly lower than those of the other groups. Tumor-volume changes of groups treated with anti-EMMPRIN monotherapy or combined therapy were significantly lower than that of the control group.

CONCLUSIONS

These data provide support for clinical studies of anti-EMMPRIN therapy with gemcitabine for pancreatic cancer treatment.

Basigin: a multifunctional membrane protein with an emerging role in infections by malaria parasites

INTRODUCTION

Malaria is one of the most serious infectious diseases at the beginning of the twenty-first century. Various membrane proteins are present in Plasmodium falciparum, the principal malaria pathogen. Among them, P. falciparum reticulocyte-binding protein homolog 5 (PfRh5) is indispensable for erythrocyte invasion, and has become a promising vaccine target. Basigin (CD147, EMMPRIN) has been identified as the erythrocyte receptor of PfRh5, and shown to be essential for the invasion of multiple strains of the pathogen.

AREAS COVERED

Fundamental information on basigin is fully described, including structure as a member of the immunoglobulin superfamily and function based on its interactions with external molecules and with proteins within the same membrane. The involvement of basigin in many diseases such as cancer and inflammatory diseases is also described, the implication being that anti-basigin therapy might be helpful to treat certain illnesses. Finally, PfRh5 as a vaccine candidate is covered, and its interaction with basigin is evaluated.

EXPERT OPINION

The identification of basigin, a well-characterized membrane protein, as a receptor essential for malaria infection will contribute significantly to prevention and treatment of malaria. As an example, anti-basigin therapy can be considered an alternative approach to the treatment of drug-resistant malaria.

Human tumor cells induce angiogenesis through positive feedback between CD147 and insulin-like growth factor-I

Tumor angiogenesis is a complex process based upon a sequence of interactions between tumor cells and endothelial cells. Previous studies have shown that CD147 was correlated with tumor angiogenesis through increasing tumor cell secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). In this study, we made a three-dimensional (3D) tumor angiogenesis model using a co-culture system of human hepatocellular carcinoma cells SMMC-7721 and humanumbilical vein endothelial cells (HUVECs) in vitro. We found that CD147-expressing cancer cells could promote HUVECs to form net-like structures resembling the neo-vasculature, whereas the ability of proliferation, migration and tube formation of HUVECs was significantly decreased in tumor conditioned medium (TCM) of SMMC-7721 cells transfected with specific CD147-siRNA. Furthermore, by assaying the change of pro-angiogenic factors in TCM, we found that the inhibition of CD147 expression led to significant decrease of VEGF and insulin-like growth factor-I (IGF-I) secretion. Interestingly, we also found that IGF-I up-regulated the expression of CD147 in both tumor cells and HUVECs. These findings suggest that there is a positive feedback between CD147 and IGF-I at the tumor-endothelial interface and CD147 initiates the formation of an angiogenesis niche.

CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis.

Role of emmprin in endometrial cancer

Background

Extracellular matrix metalloproteinase inducer (Emmprin/CD147) is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. Enriched on the surface of many tumor cells, emmprin promotes tumor growth, invasion, metastasis and angiogenesis. We evaluated the clinical importance of emmprin and investigated its role in endometrial cancer.

Methods

Emmprin expression was examined in uterine normal endometrium, endometrial hyperplasia and cancer specimens by immunohistochemistry. In addition, the biological functions and inhibitory effects of an emmprin knockdown were investigated in HEC-50B and KLE endometrial cancer cell lines.

Results

The levels of emmprin expression were significantly increased in the endometrial cancer specimens compared with the normal endometrium and endometrial hyperplasia specimens (p < 0.05). The disease-free survival (DFS) and overall survival (OS) rates of patients with high emmprin expression were significantly higher than those of patients with low emmprin expression (DFS: p < 0.001; OS: p < 0.001). Emmprin knockdown by the siRNA led to cell proliferation, migration and invasion through TGF-β, EGF, NF-κB, VEGF, MMP-2, and MMP-9 expression, which in turn resulted in increased levels of E-cadherin and reduced levels of Vimentin and Snail in endometrial cancer.

Conclusions

The present findings suggest that low emmprin expression might be a predictor of favorable prognosis in endometrial cancer patients, and that emmprin may represent a potential therapeutic target for endometrial cancer.

Overexpressions of RACK1 and CD147 associated with poor prognosis in stage T1 pulmonary adenocarcinoma

BACKGROUND

RACK1 has been shown to be able to interact with some key cellular proteins involved in tumor development and progression. Our study showed that the expressions of RACK1 and CD147 are correlated with each other. The purpose of this study is to clarify the relationship between expression of RACK1 and CD147 in 180 patients with operable stage T1 human pulmonary adenocarcinoma and their clinicopathological features and prognostic significance.

METHODS

DNA transfection and RNA interference of RACK1 were conducted to produce pulmonary adenocarcinoma cell lines with differential RACK1 expression. Western blot and RT-PCR were used to quantify RACK1 and CD147 expression in protein and mRNA levels in pulmonary adenocarcinoma cell lines. Immunohistochemistry, double-labeling immunofluorescence, confocal laser scanning microscopy, and Western blot were used to correlate the clinicopathological significance of RACK1 and CD147 expression in cases of stage T1 pulmonary adenocarcinoma.

RESULTS

We detected high levels of RACK1 and CD147 mRNA as well as protein expression in pulmonary adenocarcinoma in vitro. In pulmonary adenocarcinoma, the expression of RACK1 and CD147 were correlated both in vitro and in vivo. Our clinicopathological analysis demonstrated that RACK1 or CD147 expression correlated with higher incidence of lymph node metastasis and lower differentiation than tumors that were negative for expression of either RACK1 or CD147. The expression of RACK1 and CD147 was not associated with the patient age or gender. Multivariate analysis demonstrated that the co-overexpression of RACK1 and CD147 was an independent prognostic factor for stage T1 pulmonary adenocarcinoma (P = 0.012).

CONCLUSIONS

Tumor invasiveness is associated with expression of RACK1 and CD147 in pulmonary adenocarcinoma. The co-expression of RACK1 and CD147 could be an important prognostic biomarker for stage T1 pulmonary adenocarcinoma.

Pilot study of CD147 protein expression in epithelial ovarian cancer using monoclonal antibody 12C3

AIM

CD147 is a membrane glycoprotein that is expressed in various cancer cells and is involved in tumor invasion and metastasis by inducing stromal fibroblastic cells to produce matrix metalloproteinases. This study was carried out to evaluate the correlation between CD147 expression and various clinicopathologic parameters, including histological grade and prognosis in a small sample set of human ovarian cancer patients.

MATERIAL AND METHODS

Paraffin-embedded surgical tissue samples from 25 patients with ovarian serous and endometrioid adenocarcinoma were stained with anti-CD147 antibody (monoclonal antibody 12C3: MoAb 12C3) for immunohistochemical analysis.

RESULTS

CD147 protein was expressed in 84.0% (21 of 25 cases) of cancerous lesions, but not in normal lesions. CD147 expression by ovarian cancer cells was inversely correlated with overall survival. There was no correlation between CD147 expression and histological grade.

CONCLUSIONS

These results suggest that measurement of CD147 expression may enhance the understanding of the pathophysiology of epithelial ovarian cancer.

Increased expression of extracellular matrix metalloproteinase inducer (CD147) in multiple myeloma: role in regulation of myeloma cell proliferation

Multiple myeloma (MM) is preceded by the asymptomatic pre-malignant state, monoclonal gammopathy of undetermined significance (MGUS). Although MGUS patients may remain stable for years, they are at increased risk of progressing to MM. A better understanding of the relevant molecular changes underlying the transition from an asymptomatic to symptomatic disease state is urgently needed. Our studies show for the first time that the CD147 molecule (extracellular matrix metalloproteinase inducer) may be having an important biological role in MM. We first demonstrate that CD147 is overexpressed in MM plasma cells (PCs) vs normal and pre-malignant PCs. Next, functional studies revealed that the natural CD147 ligand, cyclophilin B, stimulates MM cell growth. Moreover, when MM patient PCs displaying bimodal CD147 expression were separated into CD147(bright) and CD147(dim) populations and analyzed for proliferation potential, we discovered that CD147(bright) PCs displayed significantly higher levels of cell proliferation than did CD147(dim) PCs. Lastly, CD147-silencing significantly attenuated MM cell proliferation. Taken together, these data suggest that the CD147 molecule has a key role in MM cell proliferation and may serve as an attractive target for reducing the proliferative compartment of this disease.

The pathobiological features of gastrointestinal cancers (Review)

Gastrointestinal adenocarcinoma (GIA) is a common malignant disease worldwide. Its tumorigenesis and progression is a multistage process with the involvement of a multifactorial etiology. Knowledge regarding altered expression of these genes during carcinogenesis may not only provide information about the molecular events during the initiation and progression of cancer, but may also result in the discovery of biological markers for the evaluation of cancer diagnosis and prognosis. In this review, we assessed molecular markers of pathogenesis, invasion, metastasis and prognosis, such as tumor suppressor and metastasis suppressor genes, and angiogenesis, cell adhesion, cell mobility, ER stress, mucin production, threonine protein kinase and REG family protein expression, by the establishment of tissue microarray (TMA) of GIA and immunohistochemistry (IHC) by intermittent microwave irradiation and in situ hybridization (ISH). Finally, we characterized the pathobiological features of Lauren's and WHO subtypes. It was found that the aberrant and cell-specific expression of these molecules is important in the malignant transformation of gastrointestinal epithelium and subsequent progression. These molecules also underlie the histogenic mechanisms of gastric carcinoma according to Lauren's and WHO classification. The combination of TMA, IHC and ISH may be widely applied to screen for molecular markers in GIA.

Association of increased ligand cyclophilin A and receptor CD147 with hypoxia, angiogenesis, metastasis and prognosis of tongue squamous cell carcinoma

AIMS

We evaluated the association of ligand cyclophilin A (CypA) and receptor CD147 with hypoxia, angiogenesis, lymph node metastasis and prognosis of patients with tongue squamous cell carcinoma (TSCC).

METHODS AND RESULTS

We studied the expression of CypA, CD147, hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor A and C (VEGF-A and VEGF-C) protein by immunohistochemistry in 80 specimens of TSCC. CypA, CD147, HIF-1α, VEGF-A and VEGF-C were overexpressed in TSCCs, and were significantly higher than those in normal oral mucosa tissues (P<0.01). Increased ligand CypA and receptor CD147 correlated significantly with expression of HIF-1α, VEGF-A and VEGF-C. A significant relationship between VEGF-A and VEGF-C was also detected (P<0.01). Patients with overexpression of CypA, CD147, HIF-1α and VEGF-C had significantly worse overall survival (P<0.05) using Kaplan-Meier analysis. Multivariate Cox regression analysis showed that HIF-1α, recurrence and distant metastasis were independent prognostic factors on overall survival in TSCC patients.

CONCLUSIONS

The association of expression of ligand CypA and receptor CD147 with carcinogenesis, hypoxia, angiogenesis, metastasis and prognosis of TSCC suggests that ligand CypA and receptor CD147 may have prognostic value and could be regarded as potential therapeutic targets in TSCC.

Significance of expression of EMMPRIN and MT1-MMP in primary gastric carcinoma and associated lymph node metastases

AIM: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and membrane-type matrix metalloproteinase-1 (MT1-MMP) proteins in primary gastric carcinoma (GC) and associated lymph node metastases, and to analyze their correlation with clinicopathologic parameters of GC.

METHODS: Expression of EMMPRIN and MT1-MMP proteins were detected by quantum dot-based immunofluorescence technology on tissue microarrays including 204 cases of GC, 21 cases of non-cancerous gastric mucosa tissue, and 20 cases of metastatic lymph node tissue. The results were analyzed using a semiquantitative method.

RESULTS: The positive rates of EMMPRIN and MT1-MMP protein expression were highest metastatic lymph nodes, followed by GC, chronic atrophic gastritis with intestinal metaplasia, and normal gastric mucosa, which showed a decreasing trend. The positive rates of EMMPRIN and MT1-MMP protein expression were significantly higher in GC and lymph node metastases than in normal gastric mucosa. The expression of EMMPRIN protein was positively correlated with infiltration depth, higher TNM stage and lymph node metastasis, while expression of MT1-MMP protein was positively correlated with higher TNM stage and lymph node metastasis. A positive correlation was observed between EMMPRIN and MT1-MMP protein expression in GC (r = 0.584, P = 0.001).

CONCLUSION: EMMPRIN and MT1-MMP proteins may play a synergistic role in the development and progression of GC.

EMMPRIN contributes to the in vitro invasion of human salivary adenoid cystic carcinoma cells

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a transmembrane glycoprotein that is involved in tumor invasion by stimulating matrix metalloproteinase (MMP) expression. Our previous immunohistochemical study found that the expression of EMMPRIN in salivary adenoid cystic carcinoma (SACC) was positively correlated with tumor perineural and perivascular invasion. The present study was designed to further investigate the role of EMMPRIN in the invasion of SACC. Western blot results showed that EMMPRIN was upregulated in the highly metastatic SACC cell line SACC-LM, compared to SACC-83, a SACC cell line with low metastatic ability. Blocking of EMMPRIN by its antibody significantly decreased the adhesion, secretion of MMP-2 and MMP-9, and invasion activity of SACC-LM cells in vitro (P<0.01). Co-cultures of SACC-LM cells with fibroblasts significantly produced elevated levels of MMP-2 and MMP-9, and promoted the in vitro invasion activity of SACC-LM cells, compared with cultures of SACC-LM cells alone (P<0.01). These results indicate that EMMPRIN may play an important role in the invasion of SACC by stimulating the expression of MMP-2 and MMP-9 in tumor and stromal cells.

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.

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.

Extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) as a novel regulator of myogenic cell differentiation

Matrix metalloproteinases (MMPs) are thought to play an important role in skeletal muscle cell growth and differentiation. In view of the MMP inducing function of EMMPRIN/CD147, its role in myogenic cell differentiation was investigated. EMMPRIN level increased during differentiation of both rat primary myoblasts derived from satellite cells and mouse C2.7 myogenic cells and was associated with an alteration in its molecular forms. In parallel, expression of pro-MMP-9 gradually decreased and that of pro-MMP-2 and active MMP-2 increased. While small interfering RNA (siRNA) inhibition of EMMPRIN expression accelerated cell differentiation, exogenously added recombinant EMMPRIN inhibited differentiation by an MMP-mediated mechanism, as the MMP inhibitor marimastat abrogated EMMPRIN's effect. Our results further suggest that EMMPRIN regulates differentiation through an MMP activation of transforming growth factor beta (TGFβ), a known inhibitor of myoblast's differentiation, as the increased activation and signaling of TGFβ by EMMPRIN was attenuated in the presence of marimastat. EMMPRIN inhibition may thus represent a novel strategy in the treatment of muscular degenerative disorders.

EMMPRIN and fascin expression in non-small cell lung carcinoma

Fascin and EMMPRIN (CD 147) have a demonstrated relationship with the invasion and progression of many tumors. The aim of this study was to analyze fascin and EMMPRIN expression in non-small cell lung carcinoma and their relationship with clinicopathologic features. Fascin and EMMPRIN expression levels were investigated via the immunohistochemistry of paraffin-embedded tissues of 64 patients with non-small cell lung carcinoma, including 46 squamous cell carcinoma and 18 adenocarcinoma patients. The patients were scored on the basis of staining extent and intensity, and were then assigned a combined score. Fascin expression was present in 44 of 46 (95.6%) patients with SCC and 16 of 18 (88.8%) patients with adenocarcinoma. There was a significant correlation between fascin expression and tumor stage in the SCC and adenocarcinoma groups. EMMPRIN expression was observed in all patients with SCC (46 of 46, 100%) and 16 of 18 (88.8%) patients with adenocarcinoma. There was significant correlation between EMMPRIN expression and both tumor stage and diameter in the SCC group, but not in the adenocarcinoma group. This study revealed that high levels of fascin and EMMPRIN expression may indicate the importance of their roles in the progression of non-small cell lung carcinoma and they could be used as prognostic marker for these tumors.

Expression of EMMPRIN in adenoid cystic carcinoma of salivary glands: correlation with tumor progression and patients' prognosis

Extracellular matrix metalloproteinase inducer (EMMPRIN) plays a critical role in the progression of malignancies by stimulating expression of metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF) in stromal cells. However, the expression of EMMPRIN in adenoid cystic carcinoma (ACC) of salivary glands, and its correlation with patients' prognosis have never been investigated thus far. In the present study, the expression of EMMPRIN was examined in 72 ACCs and 20 normal salivary gland tissues by immunohistochemistry. The expression of MMP-2, MMP-9, VEGF, Ki-67 index, and microvessel density (MVD) labeled by CD31 were also assessed by immunohistochemistry in ACCs. The positivity of EMMPRIN in ACCs was 62.5%, which was significantly higher than that in normal salivary gland tissues (P<0.01). EMMPRIN expression was positively correlated with tumor size, histotypes, clinical stage, perineural invasion, vascular invasion, metastasis, expression of MMP-2, MMP-9, VEGF, Ki-67 index, and MVD (P<0.05), but not with gender, age, tumor site or recurrence (P>0.05). Multivariate analysis showed that EMMPRIN expression, Ki-67 index, and solid histotype had an independent prognostic effect on overall survival (P<0.05). According to our findings, EMMPRIN might actively be involved in the growth, angiogenesis, invasion and metastasis of ACCs. Measurement of EMMPRIN may be helpful in predicting patients' prognosis and understanding the malignant behaviors of ACCs.

Interaction of stellate cells with pancreatic carcinoma cells

Pancreatic cancer is characterized by its late detection, aggressive growth, intense infiltration into adjacent tissue, early metastasis, resistance to chemo- and radiotherapy and a strong “desmoplastic reaction”. The dense stroma surrounding carcinoma cells is composed of fibroblasts, activated stellate cells (myofibroblast-like cells), various inflammatory cells, proliferating vascular structures, collagens and fibronectin. In particular the cellular components of the stroma produce the tumor microenvironment, which plays a critical role in tumor growth, invasion, spreading, metastasis, angiogenesis, inhibition of anoikis, and chemoresistance. Fibroblasts, myofibroblasts and activated stellate cells produce the extracellular matrix components and are thought to interact actively with tumor cells, thereby promoting cancer progression. In this review, we discuss our current understanding of the role of pancreatic stellate cells (PSC) in the desmoplastic response of pancreas cancer and the effects of PSC on tumor progression, metastasis and drug resistance. Finally we present some novel ideas for tumor therapy by interfering with the cancer cell-host interaction.

CD147 and VEGF co-expression predicts prognosis in patients with acute myeloid leukemia

OBJECTIVE

To investigate the possible role of CD147 and vascular endothelial growth factor in progression and prognosis of acute myeloid leukemia.

METHODS

Immunohistochemical staining was performed to detect the expression of CD147 and vascular endothelial growth factor in paraffin-embedded sections from 62 bone marrow biopsies obtained from an equal number of patients with newly diagnosed acute myeloid leukemia.

RESULTS

CD147 and vascular endothelial growth factor expression in the bone marrow of acute myeloid leukemia patients were significantly higher than those in normal controls (both P < 0.001). Expression of them was significantly increased in patients with a high degree of microvessel density compared with those with a low degree (CD147: P = 0.009; vascular endothelial growth factor: P = 0.01) and correlated well with bone marrow microvessel density (CD147: P = 0.01; vascular endothelial growth factor: P = 0.02). In addition, higher levels of CD147 and vascular endothelial growth factor were also found in acute myeloid leukemia patients with an unfavorable karyotype compared with those with intermediate and favorable karyotypes (both P = 0.01). Moreover, the expression of CD147 was significantly correlated with that of vascular endothelial growth factor (P < 0.001). Furthermore, the co-expression of CD147 and vascular endothelial growth factor in the bone marrow indicated a poor prognosis in acute myeloid leukemia and was an independent prognostic factor for overall survival by multivariate analysis.

CONCLUSIONS

Our data show for the first time that the co-expression of CD147 and vascular endothelial growth factor may indicate a poor prognosis in acute myeloid leukemia and may be a highly sensitive marker for predicting the clinical outcome of patients.

RNAi-mediated silencing of CD147 inhibits tumor cell proliferation, invasion and increases chemosensitivity to cisplatin in SGC7901 cells in vitro

Background

CD147 is a widely distributed cell surface glycoprotein that belongs to the Ig superfamily. CD147 has been implicated in numerous physiological and pathological activities. Enriched on the surface of many tumor cells, CD147 promotes tumor growth, invasion, metastasis and angiogenesis and confers resistance to some chemotherapeutic drugs. In this study, we investigated the possible role of CD147 in the progression of gastric cancer.

Methods

Short hairpin RNA (shRNA) expressing vectors targeting CD147 were constructed and transfected into human gastric cancer cells SGC7901 and CD147 expression was monitored by quantitative realtime RT-PCR and Western blot. Cell proliferation, the activities of MMP-2 and MMP-9, the invasive potential and chemosensitivity to cisplatin of SGC7901 cells were determined by MTT, gelatin zymography, Transwell invasion assay and MTT, respectively.

Results

Down-regulation of CD147 by RNAi approach led to decreased cell proliferation, MMP-2 and MMP-9 activities and invasive potential of SGC7901 cells as well as increased chemosensitivity to cisplatin.

Conclusion

CD147 involves in proliferation, invasion and chemosensitivity of human gastric cancer cell line SGC7901, indicating that CD147 may be a promising therapeutic target for gastric cancer.

Up-regulated EMMPRIN/CD147 protein expression might play a role in colorectal carcinogenesis and its subsequent progression without an alteration of its glycosylation and mRNA level

PURPOSE

Extracellular matrix metalloproteinase inducer (EMMPRIN) was reported to involve in the invasion and metastasis of malignancies by regulating the expression of vascular endothelial growth factor (VEGF) in stromal and cancer cells. The study aimed to clarify the role of EMMPRIN expression in tumorigenesis and progression of colorectal carcinomas (CRC).

METHODS

EMMPRIN expression was examined on tissue microarray containing colorectal carcinomas, adenoma and non-neoplastic mucosa (NNM) by immunohistochemistry and in situ hybridization (ISH). Colorectal carcinoma cell lines (DLD-1, HCT-15, SW480 and WiDr) and tissues were studied for EMMPRIN expression by Western blot or RT-PCR, followed by sequencing.

RESULTS

All carcinoma cell lines showed EMMPRIN expression at both mRNA and protein levels. Two synonymous mutations were found in carcinoma cell lines at codon109 (GCT → GCC: Ala) or 179 (GAT → GAC: Asp). Frozen CRC tissues displayed higher EMMPRIN expression than paired NNM (P < 0.05). EMMPRIN expression was immunohistochemically stronger in colorectal high-grade adenoma, adenocarcinoma and metastatic carcinoma than non-neoplastic superficial epithelium and low-grade adenoma (P < 0.05). In contrast, its mRNA level was similar from colorectal NNM, adenoma to adenocarcinoma by ISH, in line with the findings of RT-PCR (P > 0.05). Immunohistochemically, EMMPRIN expression was positively correlated with tumor size, depth of invasion, vascular or lymphatic invasion, grade of infiltration (INF), ki-67 and VEGF expression of CRCs (P < 0.05). Among them, depth of invasion was an independent associated factor for EMMPRIN expression in CRCs (P < 0.05).

CONCLUSIONS

Up-regulated EMMPRIN protein expression might contribute to colorectal carcinogenesis without the alteration of its glycosylation and mRNA level. Aberrant EMMPRIN protein expression might promote growth or invasion of CRCs possibly through increased ki-67 expression and inducible angiogenesis via up-regulating VEGF expression.

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.

Involvement of inactive GSK3beta overexpression in tumorigenesis and progression of gastric carcinomas

Glycogen synthase kinase 3beta is reported to repress Wnt/beta-catenin pathway and regulate the balance between cellular proliferation and apoptosis. Its inactivation by ser(9) phosphorylation might play a critical role in the tumorigenesis and development of malignancies. Here, the expression of phosphorylated glycogen synthase kinase 3beta at ser(9) was examined in gastric carcinoma and adjacent non-neoplastic mucosa by immunohistochemistry and Western blot, and compared with the clinicopathological parameters of carcinomas, including the expression of vascular endothelial growth factor, extracellular matrix metalloproteinase inducer and beta-catenin, and microvessel density labeled by CD34, as well as survival data. Gastric carcinoma cell lines (MKN28, MKN45, AGS, GT-3 TKB, KATO-III and HGC-27) were studied for the phosphorylated kinase by Western blot and for its encoding mRNA by RT-PCR, followed by sequencing. All carcinoma cell lines showed strong expression of the phosphorylated kinase and its encoding mRNA.There were two isoforms of glycogen synthase kinase 3beta in all carcinoma cell lines and a synonymous mutation in HGC-27 carcinoma cell line at codon 65(GGA-->GGT: Gly). The phosphorylated kinase was localized in the cytoplasm of gastric carcinoma cell lines or carcinomas. It was more expressed in gastric carcinomas than that in non-neoplastic mucosa (P < .05) in line with the data of Western blot. There was a higher expression of the phosphorylated kinase in men carcinoma patients than that in women (P < .05). Its expression was positively correlated with depth of invasion, lymphatic and venous invasion, lymph node metastasis, Union Internationale le Contre Cancer staging, expression of vascular endothelial growth factor and extracellular matrix metalloproteinase inducer in gastric carcinoma (P < .05). Survival analysis indicated the phosphorylated kinase expression to be positively linked to poor prognosis (P< 05), but not independent (P>.05). Three independent prognostic factors, depth of invasion, lymphatic and venous invasion, concordantly influenced its relationship with prognosis (P < .05). Our study indicated that up-regulated expression of phosphorylated glycogen synthase kinase 3beta at ser(9) was closely linked to gastric carcinogenesis and subsequent progression, and could be employed as a good indicator of aggressive behaviors and prognosis of gastric carcinoma.

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.

Inhibitory effects of polysaccharide extract from Spirulina platensis on corneal neovascularization

PURPOSE

To assess the effects of polysaccharide extract from Spirulina platensis (PSP) on corneal neovascularization (CNV) in vivo and in vitro.

METHODS

PSP was extracted from dry powder of Spirulina platensis. Its anti-angiogenic activity was evaluated in the mouse corneal alkali burn model after topical administration of PSP four times daily for up to seven days. Corneal samples were processed for histochemical, immunohistochemical, and gene expression analyses. The effects of PSP on proliferation, migration, tube formation, and serine threonine kinase (AKT) and extracellular regulated kinase1/2 (ERK1/2) signaling levels in vascular endothelial cells were determined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3, 5-di-phenytetrazoliumromide (MTT) and carboxyfluorescein succinimidyl ester (CFSE) labeling assays, wound healing assay, Matrigel tube formation assay, and western blot.

RESULTS

Topical application of PSP significantly inhibited CNV caused by alkali burn. Corneas treated with PSP showed reduced levels of platelet endothelial cell adhesion molecule (CD31) and stromal cell-derived factor 1 (SDF1) proteins, reduced levels of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP2), matrix metalloproteinase-9 (MMP9), SDF1, and tumor necrosis factor-alpha (TNF-alpha) mRNAs, and an increased level of pigment epithelium-derived factor (PEDF) mRNA. These are parameters that have all been related to CNV and/or inflammation. In human vascular endothelial cells, PSP significantly inhibited proliferation, migration, and tube formation in a dose-dependent manner. Furthermore, PSP also decreased the levels of activated AKT and ERK 1/2.

CONCLUSIONS

These data suggest that polysaccharide extract from Spirulina platensis is a potent inhibitor of CNV and that it may be of benefit in the therapy of corneal diseases involving neovascularization and inflammation.

Upregulation of caveolin-1 and CD147 expression in nasopharyngeal carcinoma enhanced tumor cell migration and correlated with poor prognosis of the patients

Expression of caveolin-1 (Cav-1) and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) and their prognostic significance were analyzed in archive NPC samples. Cav-1 and CD147 were overexpressed in 49.48% (96/194) and 59.39% (117/197) of NPC, respectively. Both Cav-1 and CD147 expression levels correlated significantly with metastasis (p = 0.025 and 0.017, respectively) and a lower 5-year survival rate (p = 0.02 and 0.0009, respectively). In addition, Cav-1 expression levels correlated significantly with local recurrence (p = 0.038). Multivariate Cox regression analysis indicated that combination of high Cav-1 and CD147 expression was a significant, independent prognosis predictor in patients with NPC (HR = 2.135; p = 0.006). Functional studies revealed that overexpression of Cav-1 promoted secretion of MMP-3 and MMP-11 (active) proteins, as well as an increase in the migratory ability of CNE1 and CNE2 cells, while siRNA-mediated silencing of Cav-1 or CD147 led to reduced levels of MMP-3 and MMP-11(active) secretion, and reduced migration capacity of CNE1 and CNE2 cells. We observed a positive correlation between Cav-1 and CD147 expression in NPC (rho = 0.330, p = 0.000), CD147 protein levels were upregulated in Cav-1 overexpressing CNE1 and CNE2 cells, whereas siRNA-mediated silencing of Cav-1 led to the downregulation of CD147 expression. Our results indicate that Cav-1 and CD147 overexpression predict poor NPC prognosis and enhanced tumor cell migration, which is associated with MMP-3 and MMP-11 (active) secretion.

The prognostic value of CD147/EMMPRIN is associated with monocarboxylate transporter 1 co-expression in gastric cancer

The aim of the present work was to assess the role of monocarboxylate transporters (MCTs), namely MCT1 and MCT4 as well as MCT/CD147 co-expression in gastric tissues and evaluate their clinico-pathological significance in gastric carcinoma. For that, we analysed the immunohistochemical expression of MCT1, MCT4 and CD147, in a large series of gastric samples, including non-neoplastic, tumour and metastatic tissues. A significant decrease in MCT4 plasma membrane expression was observed from non-neoplastic to gastric primary malignant tissues and to lymph-node metastasis and both MCT1 and MCT4 correlated with CD147. Importantly, both MCT4 and CD147 were more frequently expressed in Lauren's intestinal-type tumours and MCT1/CD147 co-expression was associated with advanced gastric carcinoma, Lauren's intestinal type, TNM staging and lymph-node metastasis. Our results showed that the prognostic value of CD147 was associated with MCT1 co-expression in gastric cancer cells, supporting the view that CD147 plasma membrane activity is dependent on MCT co-expression.

Correlation of the expression of EMMPRIN and HER-2 proteins with the invasiveness and metastasis of human gastric carcinoma

AIM: To investigate the correlation of the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and human epidermal growth factor receptor 2 (HER-2/neu) with the invasiveness and metastasis of human gastric carcinomas, as well as the correlation between the expression of these two proteins in human gastric carcinoma.

METHODS: The expression of EMMPRIN and HER-2 proteins was detected by quantum dot-based immunofluorescence histochemistry using 150 tissue microarrays containing 70 gastric carcinoma specimens and 5 normal gastric mucosal specimens to analyze the correlation of their expression with the clinicopathologic characteristics of gastric carcinoma.

RESULTS: The positive rate of EMMPRIN protein in the gastric carcinoma was significantly higher than that in normal gastric mucosa (72.86% vs 20.00%, P = 0.029), whereas no significant difference (P = 0.063) was observed in the positive rate of HER-2 protein though the rate in the gastric carcinoma (47.14%) was higher than that in normal gastric mucosa. EMMPRIN and HER-2 protein expression was not correlated with patient age and sex, the degree of differentiation, the depth of tumor invasion and clinical TNM stage (P > 0.05), but significantly associated with lymph node metastasis (P < 0.05). Moreover, a positive correlation was observed between the expression of EMMPRIN and HER-2 proteins in 70 gastric carcinoma specimens (r = 0.383, P = 0.001).

CONCLUSION: EMMPRIN and HER-2 may synergistically promote the lymph node metastasis of gastric carcinomas.

Solution characterization of the extracellular region of CD147 and its interaction with its enzyme ligand cyclophilin A

The CD147 receptor plays an integral role in numerous diseases by stimulating the expression of several protein families and serving as the receptor for extracellular cyclophilins; however, neither CD147 nor its interactions with its cyclophilin ligands have been well characterized in solution. CD147 is a unique protein in that it can function both at the cell membrane and after being released from cells where it continues to retain activity. Thus, the CD147 receptor functions through at least two mechanisms that include both cyclophilin-independent and cyclophilin-dependent modes of action. In regard to CD147 cyclophilin-independent activity, CD147 homophilic interactions are thought to underlie its activity. In regard to CD147 cyclophilin-dependent activity, cyclophilin/CD147 interactions may represent a novel means of signaling since cyclophilins are also peptidyl–prolyl isomerases. However, direct evidence of catalysis has not been shown within the cyclophilin/CD147 complex. In this report, we have characterized the solution behavior of the two most prevalent CD147 extracellular isoforms through biochemical methods that include gel-filtration and native gel analysis as well as directly through multiple NMR methods. All methods indicate that the extracellular immunoglobulin-like domains are monomeric in solution and, thus, suggest that CD147 homophilic interactions in vivo are mediated through other partners. Additionally, using multiple NMR techniques, we have identified and characterized the cyclophilin target site on CD147 and have shown for the first time that CD147 is also a substrate of its primary cyclophilin enzyme ligand, cyclophilin A.

HAb18G/CD147 inhibits starvation-induced autophagy in human hepatoma cell SMMC7721 with an involvement of Beclin 1 down-regulation

HAb18G/CD147, a transmembrane glycoprotein highly expressed in various types of malignant cells, mainly functions as an inducer of matrix metalloproteinases to promote tumor growth, invasion and metastasis. However, whether there are other mechanisms underlying the role of HAb18G/CD147 in tumor progression remains to be elucidated. In this study, we investigated the functional effects of HAb18G/CD147 on autophagy in hepatoma cell line SMMC7721 using immunofluorescence staining, Western blot and transmission electronmicroscopy. Our data showed that specific small interference RNA (siRNA) considerably down-regulated the expression of HAb18G/CD147 in SMMC7721 cells at both messenger RNA (mRNA) and protein levels. The down-regulation of HAb18G/CD147 significantly promoted starvation-induced autophagy in a dose-dependent manner. Using trypan blue exclusion assay, we found that HAb18G/CD147 notably enhanced the survival of SMMC7721 cells through inhibiting starvation-induced autophagy. In addition, we demonstrated that HAb18G/CD147 down-regulated the expression of autophagy-regulating protein Beclin 1 in SMMC7721 cells. Furthermore, our data indicated that HAb18G siRNA-transfected SMMC7721 cells had a significantly decreased level of phosphorylated serine/threonine protein kinase B (pAkt) and the expression of Beclin 1 was inversely associated with the level of pAkt, suggesting that the Class I phosphatidylinositol 3 kinase-Akt pathway may be involved in the down-regulation of Beclin 1 by HAb18G/CD147. Overall, we provide the first experimental evidence to show that HAb18G/CD147 may play an important role in the inhibitory regulation of autophagy. Therefore, our data suggest a new molecular mechanism for HAb18G-mediated hepatoma progression.

EMMPRIN expression in tongue squamous cell carcinoma

BACKGROUND

Extracellular matrix metalloproteinase inducer (EMMPRIN) is identified as a tumor-cell membrane protein that stimulates matrix metalloproteinases (MMPs) production. Several studies have shown that higher EMMPRIN expression is associated with shorter survival time and correlated significantly with more advanced clinico-parameters of cancer. The aim of this study was to investigate the relationship between clinico-pathologic characteristics and EMMPRIN, and prognostic significance of EMMPRIN expression in human tongue squamous cell carcinoma.

METHODS

Extracellular MMP inducer expression was examined immunohistochemically on paraffin-embedded tissue specimens from 68 patients with tongue squamous cell carcinoma and who underwent radical surgeries from 1996 to 2006. The 68 patients were followed up from 1 to 119 months, with an average of 27.5 months. Nonparametric tests were performed for the comparison of EMMPRIN expression between two independent groups. Survival analysis was performed to find the prognostic significance of EMMPRIN expression.

RESULTS

We found that EMMPRIN expression in tongue squamous cell carcinoma is significantly higher than that in non-cancerous epithelium adjacent to carcinoma of tongue. In addition, EMMPRIN expression is significantly associated with tumor diameter and clinical stage in the samples, but did not correlate with gender, age, tumor metastasis, and pathological grade. Finally, survival analysis indicates that EMMPRIN overexpression correlates significantly with poor overall survival in the patient cohort.

CONCLUSION

These results suggest that EMMPRIN might represent an attractive target for immunotherapeutic approaches in a subgroup of patients with tongue squamous cell carcinoma.

CD147 impacts angiogenesis and metastasis formation

CD147 is highly expressed on many tumor cells; its role for tumor invasiveness and metastasis has been deduced from its capacity to induce MMPs, i.e., MMP-1, -2, -3, and -9. However, in the murine B16 melanoma model, MMP-2/-9 expression occurs independent of CD147. To scrutinize the impact of CD147 on metastasis formation and angiogenesis in this model, CD147 was stably knocked down in B16 cells. This silencing of CD147 expression resulted in a reduced capability of the tumor cells to metastasize to the draining lymph nodes. Notably, the CD147 knock down caused a decreased VEGF expression in vivo accompanied by reduced blood vessel formation. Thus, in the B16 melanoma model, CD147 promotes metastasis formation by induction of angiogenesis in an MMP independent manner.

Upregulation of HAb18G/CD147 in activated human umbilical vein endothelial cells enhances the angiogenesis

Previous studies demonstrated that CD147 molecule, highly expressed on the surface of various malignant tumor cells, significantly correlated with the malignancy of these cancers; however, the role of HAb18G/CD147 in endothelial cells has yet to be established. In this study, we found that the expression of HAb18G/CD147 was significantly upregulated in activated HUVECs. The inhibition of HAb18G/CD147 expression by specific siRNA led to significantly decreased angiogenesis in vitro. Our data indicate that HAb18G/CD147 may regulate angiogenesis via several mechanisms including proliferation, survival, migration, MMPs secretion, and PI3K/Akt activation. Our findings for the first time suggest that upregulation of HAb18G/CD147 in activated HUVECs might play an important role in angiogenesis.