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

A Potential Prognostic Gene Signature Associated with p53-Dependent NTRK1 Activation and Increased Survival of Neuroblastoma Patients

Neuroblastoma is the most common extracranial solid tumour in children, comprising close to 10% of childhood cancer-related deaths. We have demonstrated that activation of NTRK1 by TP53 repression of PTPN6 expression is significantly associated with favourable survival in neuroblastoma. The molecular mechanisms by which this activation elicits cell molecular changes need to be determined. This is critical to identify dependable biomarkers for the early detection and prognosis of tumours, and for the development of personalised treatment. In this investigation we have identified and validated a gene signature for the prognosis of neuroblastoma using genes differentially expressed upon activation of the NTRK1-PTPN6-TP53 module. A random survival forest model was used to construct a gene signature, which was then assessed across validation datasets using Kaplan-Meier analysis and ROC curves. The analysis demonstrated that high BASP1, CD9, DLG2, FNBP1, FRMD3, IL11RA, ISGF10, IQCE, KCNQ3, and TOX2, and low BSG/CD147, CCDC125, GABRB3, GNB2L1/RACK1 HAPLN4, HEBP2, and HSD17B12 expression was significantly associated with favourable patient event-free survival (EFS). The gene signature was associated with favourable tumour histology and NTRK1-PTPN6-TP53 module activation. Importantly, all genes were significantly associated with favourable EFS in an independent manner. Six of the signature genes, BSG/CD147, GNB2L1/RACK1, TXNDC5, FNPB1, B3GAT1, and IGSF10, play a role in cell differentiation. Our findings strongly suggest that the identified gene signature is a potential prognostic biomarker and therapeutic target for neuroblastoma patients and that it is associated with neuroblastoma cell differentiation through the activation of the NTRK1-PTPN6-TP53 module.

Depleted uranium induces thyroid damage through activation of ER stress via the thrombospondin 1-PERK pathway

Depleted uranium (DU) can cause damage to the body, but its effects on the thyroid are unclear. The purpose of this study was to investigate the DU-induced thyroid damage and its potential mechanism in order to find new targets for detoxification after DU poisoning. A model of acute exposure to DU was constructed in rats. It was observed that DU accumulated in the thyroid, induced thyroid structure disorder and cell apoptosis, and decreased the serum T4 and FT4 levels. Gene screening showed that thrombospondin 1 (TSP-1) was a sensitive gene of DU, and the expression of TSP-1 decreased with the increase of DU exposure dose and time. TSP-1 knockout mice exposed to DU had more severe thyroid damage and lower serum FT4 and T4 levels than wild-type mice. Inhibiting the expression of TSP-1 in FRTL-5 cells aggravated DU-induced apoptosis, while exogenous TSP-1 protein alleviated the decreased viability in FRTL-5 cells caused by DU. It was suggested that DU may caused thyroid damage by down-regulating TSP-1. It was also found that DU increased the expressions of PERK, CHOP, and Caspase-3, and 4-Phenylbutyric (4-PBA) alleviated the DU-induced FRTL-5 cell viability decline and the decrease levels of rat serum FT4 and T4 caused by DU. After DU exposure, the PERK expression was further up-regulated in TSP-1 knockout mice, and the increased expression of PERK was alleviated in TSP-1 over-expressed cells, as well as the increased expression of CHOP and Caspase-3. Further verification showed that inhibition of PERK expression could reduce the DU-induced increased expression of CHOP and Caspase-3. These findings shed light on the mechanism that DU may activate ER stress via the TSP 1-PERK pathway, thereby leading to thyroid damage, and suggest that TSP-1 may be a potential therapeutic target for DU-induced thyroid damage.

Regulation of Traction Force through the Direct Binding of Basigin and Calpain 4

Traction force and mechanosensing (the ability to sense mechanical attributes of the environment) are two important factors used by a cell to modify behavior during migration. Previously it was determined that the calpain small subunit, calpain 4, regulates the production of traction force independent of its proteolytic holoenzyme. A proteolytic enzyme is formed by calpain4 binding to either of its catalytic partners, calpain 1 and 2. To further understand how calpain 4 regulates traction force, we used two-hybrid analysis to identify more components of the traction pathway. We discovered that basigin, an integral membrane protein and a documented matrix-metalloprotease (MMP) inducer binds to calpain 4 in two-hybrid and pull-down assays. Traction force was deficient when basigin was silenced in MEF cells, and defective in substrate adhesion strength. Consistent with Capn4 ^-/- MEF cells, the cells deficient in basigin responded to localized stimuli. Together these results implicate basigin in the pathway in which calpain 4 regulates traction force independent of the catalytic large subunits.

Pseudolaric Acid B Inhibits Proliferation, Invasion, and Angiogenesis in Esophageal Squamous Cell Carcinoma Through Regulating CD147

Background

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive system. Studies have shown that pseudolaric acid B (PAB) has several pharmacological effects like anti-microtubule, anti-angiogenesis, and antitumor functions, while the effect and mechanism of PAB on esophageal cancer are still unclear. This study was designed to investigate the effects of PAB on ESCC.

Methods

To study the effects of PAB on the biological function through a series of in vitro and in vivo experiments.

Results

The results revealed that PAB inhibited the proliferation, invasion, and migration, but promoted the apoptosis of ESCC. Moreover, PAB restrained the growth of cancer cells in vivo and inhibited the angiogenesis of HUVEC in mice with ESCC. CD147 expression was increased in the esophageal squamous cell lines, and interference with CD147 hindered the proliferation, invasion, and migration of ESCC cells, and inhibited the growth and angiogenesis of the esophageal squamous cell line. PAB reduced the expression of CD147 in vivo and in vitro. The expression of MMP2, 3, and 9 was increased after overexpression of CD147, which provided the opportunity to reverse the role of PAB in inhibiting proliferation, invasion, migration, and angiogenesis of ESCC.

Discussion

The results revealed that PAB inhibited the proliferation, invasion, migration, and angiogenesis of ESCC in vitro and in vivo by CD147. PAB is a promising monomer for therapy of ESCC, providing references for future research on ESCC treatment.

MiR-890 inhibits proliferation and invasion and induces apoptosis in triple-negative breast cancer cells by targeting CD147

Background

Triple-negative breast cancer (TNBC) is a type of breast cancer with a high degree of malignancy. Because of the remarkable biological characteristics of high invasion, metastasis and recurrence, TNBC is often accompanied by a poor prognosis. As a molecular characteristic of TNBC, high expression of CD147 has been confirmed by a large number of studies. However, the mechanism of CD147 expression regulation in TNBC remains elusive. In this study, we investigated the roles of miR-890 in inhibiting CD147.

Methods

Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect CD147 mRNA and miR-890 level, and western blotting was used to detect CD147 protein. Bioinformatics screening and 3′-Untranslated Region (3′-UTR) luciferase assays were used to analyze the microRNAs (miRNA) binding site. Cell proliferation, apoptosis and invasion were assessed by using CCK-8, flow cytometry and transwell assays.

Results

The upregulation of miR-890 inhibited cell proliferation and invasion, induced apoptosis in MDA-MB-231 and HCC-70 TNBC cells by negatively regulating its target gene, CD147, and the upregulation of CD147 rescued the inhibitory effects of miR-890. miR-890 targeted CD147 by binding to its 3′-UTR. Further results showed that the upregulation of miR-890 also inhibited the expression of MMPs, the downstream genes of CD147, and promoted the cleavage of Caspase-3. The CD147 recovery experiment was further confirmed by the activity changes in the downstream MMPs of CD147. In addition, it was confirmed that the effect of CD147 in promoting TNBC cell proliferation and invasion, inhibiting apoptosis was related to the change in caspase-3 activity.

Conclusion

The downregulation of miR-890 is the potential cause of high CD147 expression in TNBC, which can promote the malignant transformation of TNBC.

[The role of exosomal tetraspanins and proteases in tumor progression]

Major (CD9, CD63, CD81) and others (CD82, CD151, Tspan8) tetraspanins are widely represented in exosomes, where they interact with various proteins and form functional tetraspanin complexes. Tetraspanin complexes include proteases. Tetraspanin-associated exosomal proteases (ADAM proteases, MMPs, EMMPRIN) play an important role in the processes of cell motility, migration, invasion and formation of metastases. Also, a significant contribution to tumor progression is made by proteases that are not associated with tetraspanins. They destabilize intercellular contacts, promote migration and invasion of tumor cells, participate in the regulation of the expression IGF-I, VEGF and transcription factors activation/deactivation. The role of other proteases of exosomes in the processes of tumor progression is being clarified.

CD147 expression is associated with poor overall survival in chemotherapy treated triple-negative breast cancer

AIMS

In breast cancer models, the functional roles of CD147 in proliferation, invasion and treatment resistance have been widely reported. However, there are only a few studies examining the clinicopathological correlation and prognostic relevance of CD147 in breast cancer, especially in relation to breast cancer molecular subtypes.

METHODS

In this study, we analysed CD147 expression in a large cohort of breast cancers, correlating with clinicopathological features and the expression of a comprehensive panel of biomarkers in triple-negative breast cancer (TNBC) and non-TNBC subsets. Its relationship with patients' survival was also analysed.

RESULTS

CD147 was expressed in 11.9%(140/1174) of all cases and in 23.8% (40/168) of TNBC. The expression was associated with tumour histological subtypes (p=0.01) and most commonly seen in carcinoma with medullary features (26.0%). CD147 expression correlated with high tumour grade, presence of necrosis and basal-like breast cancer (BLBC) subtype, high Ki67 and expression of some other basal markers and stem-like markers. CD147 expression was also associated with poor overall survival in chemotherapy treated patients with TNBC.

CONCLUSIONS

CD147 is a putative marker in identifying TNBC or BLBC, and may be useful as a prognosis indicator for patients with TNBC or BLBC post chemotherapy.

Elevated CD147 expression is associated with shorter overall survival in non-small cell lung cancer

A number of studies have reported on the prognostic role of CD147 expression in non-small cell lung cancer (NSCLC); however, the results remain controversial. This study aims to investigate the impact of CD147 on the prognosis of NSCLC by means of a meta-analysis. A literature search was performed for relevant studies published before October 29, 2016. The hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated as effective measures. Sensitivity analysis and publication bias examination were also conducted. Ten eligible studies with a total of 1605 patients were included in this meta-analysis. CD147 overexpression was correlated with poor overall survival (OS) (HR=1.59, 95% CI=1.32-1.91, p<0.001). Elevated CD147 expression was associated with the presence of lymph node metastasis (OR=2.31, 95% CI=1.74-3.07, p<0.001) and advanced TNM stage (OR=3.03, 95% CI=1.24-7.39, p=0.015). However, no significant association between CD147 and sex, age, differentiation, or histology was found. No evidence of significant publication bias was identified. This meta-analysis revealed that overexpression of CD147 was associated with shorter OS, the presence of lymph node metastasis and advanced TNM stage in NSCLC. Therefore, CD147 could serve as a potential prognostic marker for NSCLC.

Prognostic role of extracellular matrix metalloproteinase inducer/CD147 in gastrointestinal cancer: a meta-analysis of related studies

The prognostic role of Extracellular matrix metalloproteinase inducer (EMMPRIN/ CD147) in gastrointestinal cancer remains controversial. We systematically reviewed the evidence of assessment of CD147 expression in gastrointestinal cancer to help clarify this issue. Pubmed, Embase, Cochrane Library and Web of Science databases were searched to identify eligible studies to evaluate the association of CD147 expression and disease-free and overall survival of gastrointestinal cancer. Hazard ratios (HRs) were pooled to estimate the effect. CD147 overexpression was significantly correlated with poor disease-free survival (HR 2.38, 95% CI 1.43–3.97) and overall survival (HR 1.64, 95% CI 1.25–2.14) of cancer patients. Furthermore, CD147 overexpression was significantly association with TNM stage (TIII/TIV vs TI/TII: OR 3.60, 95% CI 1.85–7.01), the depth of invasion (T3/T4 vs T1/T2: OR 2.04, 95% CI 1.25–3.33), lymph node metastasis (positive vs negative: 2.35, 95% CI 1.14–4.86), distant metastasis (positive vs negative: OR 4.78, 95% CI 1.43–16.00). Our analyses demonstrate that CD147 was effectively predictive of worse prognosis in gastrointestinal cancer. Moreover, Identifying CD147 may help identify new drug targets for cancer therapy.

CD147 knockdown improves the antitumor efficacy of trastuzumab in HER2-positive breast cancer cells

Trastuzumab is widely used in the clinical treatment of human epidermal growth factor receptor-2 (HER2)-positive breast cancer, but the patient response rate is low. CD147 stimulates cancer cell proliferation, migration, metastasis and differentiation and is involved in chemoresistance in many types of cancer cells. Whether CD147 alters the effect of trastuzumab on HER2-positive breast cancer cells has not been previously reported. Our study confirmed that CD147 suppression enhances the effects of trastuzumab both in vitro and in vivo. CD147 suppression increased the inhibitory rate of trastuzumab and cell apoptosis in SKBR3, BT474, HCC1954 and MDA-MB453 cells compared with the controls. Furthermore, CD147 knockdown increased expression of cleaved Caspase-3/9 and poly (ADP-ribose) polymerase (PARP) and decreased both mitogen-activated protein kinase (MAPK) and Akt phosphorylation in the four cell lines. In an HCC1954 xenograft model, trastuzumab achieved greater suppression of tumor growth in the CD147-knockdown group than in the shRNA negative control (NC) group. These data indicated that enhancement of the effect of trastuzumab on HER2-positive cells following CD147 knockdown might be attributed to increased apoptosis and decreased phosphorylation of signaling proteins. CD147 may be a key protein for enhancing the clinical efficacy of trastuzumab.

System analysis of the regulation of the immune response by CD147 and FOXC1 in cancer cell lines

CD147, encoded by BSG, is a highly glycosylated transmembrane protein that belongs to the immunological superfamily and expressed on the surface of many types of cancer cells. While CD147 is best known as a potent inducer of extracellular matrix metalloproteinases, it can also function as a key mediator of inflammatory and immune responses. To systematically elucidate the function of CD147 in cancer cells, we performed an analysis of genome-wide profiling across the Cancer Cell Line Encyclopedia (CCLE). We showed that CD147 mRNA expression was much higher than that of most other genes in cancer cell lines. CD147 varied widely across these cell lines, with the highest levels in the ovary (COLO704) and stomach (SNU668), intermediate levels in the lung (RERFLCKJ, NCIH596 and NCIH1651) and lowest levels in hematopoietic and lymphoid tissue (UT7, HEL9217, HEL and MHHCALL3) and the kidney (A704 and SLR20). Genome-wide analyses showed that CD147 expression was significantly negatively correlated with immune-related genes. Our findings implicated CD147 as a novel regulator of immune-related genes and suggest its important role as a master regulator of immune-related responses in cancer cell lines. We also found a high correlation between the expression of CD147 and FOXC1, and proved that CD147 was a direct transcriptional target of FOXC1. Our findings demonstrate that FOXC1 is a novel regulator of CD147 and confirms its role as a master regulator of the immune response.

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

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

The inhibition role of miR-22 in hepatocellular carcinoma cell migration and invasion via targeting CD147

BACKGROUND

Recently, miR-22 is identified as a tumor-suppressing microRNA in many human cancers. CD147 is a novel cancer-associated biomarker that plays an important role in the invasion and metastasis of malignant tumor. However, the involvement of miR-22 in CD147 regulation and hepatocellular carcinoma (HCC) progression and metastasis has not been investigated.

METHODS

We measured miR-22 expression level in 34 paired of HCC and matched normal tissues, HCC cell lines by real-time quantitative RT-PCR. Invasion assay, MTT proliferation assay and wound-healing assay were performed to test the invasion and proliferation of HCC cell after overexpression of miR-22. The effect of miR-22 on HCC in vivo was validated by murine xenograft model. The relationship of miR-22 and its target gene CD147 was also investigated.

RESULTS

We found that the expression of miR-22 in HCC tissues and cell lines were much lower than that in normal control, respectively. The expression of miR-22 was inversely correlated with HCC metastatic ability. Moreover, overexpression of miR-22 could significantly inhibit the HCC cell proliferation, migration and invasion in vitro and decrease HCC tumor growth in vivo. Finally, we found that miR-22 interacted with CD147 and decreased its expression, via a specific target site within the CD147 3'UTR by luciferase reporter assay. The expression of CD147 was inversely correlated with miR-22 expression in HCC tissues.

CONCLUSION

Our results suggested that miR-22 was downexpressed in HCC and inhibited HCC cell proliferation, migration and invasion through downregulating cancer-associated gene CD147 which may provide a new bio-target for HCC therapy.

Icaritin inhibits the invasion and epithelial-to-mesenchymal transition of glioblastoma cells by targeting EMMPRIN via PTEN/AKt/HIF-1α signalling

Icaritin, a hydrolytic product of icariin from the Epimedium genus, exerts anti-tumour effects on a variety of tumour cell types, mainly by inhibiting cell proliferation and inducing apoptosis. However, little is known about the role of icaritin in cancer invasion and epithelial-to-mesenchymal transition (EMT). In the present study, the glioblastoma (GBM) cell line U87MG was used as a model to investigate the effects of icaritin on the invasion and EMT of cancer cells. The results showed that icaritin significantly inhibited the invasion and EMT of GBM cells by targeting extracellular matrix metalloproteinase (EMMPRIN). Furthermore, the findings strongly indicate that the modulatory effect of icaritin on EMMPRIN is mediated via the PTEN/Akt/HIF-1α signalling pathway. The data provide the first experimental evidence of the inhibitory effect of icaritin on cancer cell invasion and EMT, thus highlighting the potential of icaritin to be employed as a promising anti-cancer agent in the treatment of GBM.

The effects of CD147 on the cell proliferation, apoptosis, invasion, and angiogenesis in glioma

To analyze the effects of extracellular matrix metalloproteinase inducer (CD147) on glioma proliferation, apoptosis, invasion, and angiogenesis. Tissue samples were obtained from 101 glioma cases while normal brain tissues were obtained from 30 brain injury cases. Immunohistochemical assay was performed to detect the expressions of CD147, CD34, and VEGF in tissue samples. QRT-PCR was performed to detect the relative expression of CD147 mRNA in human glioma cell lines. CD147 siRNA was transfected into glioma cell line U251. Cell proliferation, apoptosis, invasion, and angiogenesis were tested by MTT, flow cytometry, Transwell assay, and vasculogenic mimicry assay, respectively. Expressions of relative proteins were analyzed with western blot. CD147 was positively expressed with the percentage of 0, 37.5, 44.8, 67.9, and 85.7 % in normal tissues and glioma tissues with WHO grades I-IV, respectively, and the scores of MVDand VEGF were associated with the expression of CD147. CD147 was significantly upregulated in the human glioma cell lines (P < 0.05). Downregulated the expression of CD147 suppressed cell proliferation, blocked cell cycle, induced apoptosis, inhibited cell invasion and angiogenesis in glioma cells in vitro. The expression of CD147 was significantly associated with WHO tumor grade and angiogenesis; silencing of CD147 contributed to inhibition of glioma proliferation, invasion, and angiogenesis. Our study provided firm evidence that CD 147 is a potential glioma target for anti-angiogenic therapies.

CD147/EMMPRIN overexpression and prognosis in cancer: A systematic review and meta-analysis

CD147/EMMPRIN (extracellular matrix metalloproteinase inducer) plays an important role in tumor progression and a number of studies have suggested that it is an indicator of tumor prognosis. This current meta-analysis systematically reevaluated the predictive potential of CD147/EMMPRIN in various cancers. We searched PubMed and Embase databases to screen the literature. Fixed-effect and random-effect meta-analytical techniques were used to correlate CD147 expression with outcome measures. A total of 53 studies that included 68 datasets were eligible for inclusion in the final analysis. We found a significant association between CD147/EMMPRIN overexpression and adverse tumor outcomes, such as overall survival, disease-specific survival, progression-free survival, metastasis-free survival or recurrence-free survival, irrespective of the model analysis. In addition, CD147/EMMPRIN overexpression predicted a high risk for chemotherapy drugs resistance. CD147/EMMPRIN is a central player in tumor progression and predicts a poor prognosis, including in patients who have received chemo-radiotherapy. Our results provide the evidence that CD147/EMMPRIN could be a potential therapeutic target for cancers.

Interaction of KLF6 and Sp1 regulates basigin-2 expression mediated proliferation, invasion and metastasis in hepatocellular carcinoma

Accumulating evidence suggests that the tumor suppressor gene Krüppel-like factor 6 (KLF6) plays important roles in both development and progression of cancer. However, the role of KLF6 in hepatocellular carcinoma (HCC) remains unclear. Cancer-related molecule basigin-2 plays an important role in HCC progression and metastasis. Sp1, one of Sp/KLFs family members, regulates basigin-2 expression in HCC. The involvement of KLFs in basigin-2 regulation and HCC progression and metastasis has not been investigated. We first measured KLF6 expression levels in 50 pairs of HCC and adjacent normal tissues (ANTs) by immunohistochemistry. Specifically, low KLF6 expression but high Sp1 and basigin-2 expression were found in HCC tissues. By contrast, the ANTs showed high KLF6 expression but low Sp1 and basigin-2 expression. Kaplan-Meier analysis showed that higher expression of KLF6 was associated with better overall survival. The survival rate of KLF6-negative patients was lower than that of KLF6-positive patients (P = 0.015). We also found that KLF6 binds to the basigin-2 and Sp1 promoters and decreases their expression. Thus, we identified a microcircuitry mechanism in which KLF6 can repress basigin-2 expression directly by binding to its promoter or indirectly by inhibiting the expression of the transcription factor Sp1 to block gene expression. Additionally, overexpression of KLF6 suppressed the invasion, metastasis and proliferation of HCC cells in vitro and in vivo by targeting basigin-2. Our study provides new evidence that interaction of KLF6 and Sp1 regulates basigin-2 expression in HCC and that KLF6 represses the invasive and metastatic capacities of HCC through basigin-2.

Prognostic Indications of Elevated MCT4 and CD147 across Cancer Types: A Meta-Analysis

Background. Metabolism in the tumor microenvironment can play a critical role in tumorigenesis and tumor aggression. Metabolic coupling may occur between tumor compartments; this phenomenon can be prognostically significant and may be conserved across tumor types. Monocarboxylate transporters (MCTs) play an integral role in cellular metabolism via lactate transport and have been implicated in metabolic synergy in tumors. The transporters MCT1 and MCT4 are regulated via expression of their chaperone, CD147. Methods. We conducted a meta-analysis of existing publications on the relationship between MCT1, MCT4, and CD147 expression and overall survival and disease-free survival in cancer, using hazard ratios derived via multivariate Cox regression analyses. Results. Increased MCT4 expressions in the tumor microenvironment, cancer cells, or stromal cells were all associated with decreased overall survival and decreased disease-free survival (p < 0.001 for all analyses). Increased CD147 expression in cancer cells was associated with decreased overall survival and disease-free survival (p < 0.0001 for both analyses). Few studies were available on MCT1 expression; MCT1 expression was not clearly associated with overall or disease-free survival. Conclusion. MCT4 and CD147 expression correlate with worse prognosis across many cancer types. These results warrant further investigation of these associations.

The roles of CD147 in the progression of gliomas

Gliomas are characterized by their invasiveness, angiogenesis, glycolysis and poor prognosis. Determining how to inhibit angiogenesis and glycolysis and induce cell death in gliomas is essential to the development of an effective therapy. CD147, a highly glycosylated transmembrane glycoprotein with two Ig-like extracellular domains that belongs to the immunoglobulin superfamily, plays an important role in the regulation of tumor invasiveness, angiogenesis and glycolysis by inducing the secretion of matrix metalloproteinases and vascular endothelial growth factor and by interacting with monocarboxylate transporters. In this review, we first summarize the roles played by CD147 in gliomas and then propose that CD147 may be a complementary prognostic biomarker and a possible therapeutic target for glioma treatment.

CD147 and CD98 complex-mediated homotypic aggregation attenuates the CypA-induced chemotactic effect on Jurkat T cells

Homotypic cell aggregation plays important roles in physiological and pathological processes, including embryogenesis, immune responses, angiogenesis, tumor cell invasion and metastasis. CD147 has been implicated in most of these phenomena, and it was identified as a T cell activation-associated antigen due to its obvious up-regulation in activated T cells. However, the explicit function and mechanism of CD147 in T cells have not been fully elucidated. In this study, large and compact aggregates were observed in Jurkat T cells after treatment with the specific CD147 monoclonal antibody HAb18 or after the expression of CD147 was silenced by RNA interference, which indicated an inhibitory effect of CD147 in T cell homotypic aggregation. Knocking down CD147 expression resulted in a significant decrease in CD98, along with prominent cell aggregation, similar to that treated by CD98 and CD147 monoclonal antibodies. Furthermore, decreased cell chemotactic activity was observed following CD147- and CD98-mediated cell aggregation, and increased aggregation was correlated with a decrease in the chemotactic ability of the Jurkat T cells, suggesting that CD147- and CD98-mediated homotypic cell aggregation plays a negative role in T cell chemotaxis. Our data also showed that p-ERK, p-ZAP70, p-CD3ζ and p-LCK were significantly decreased in the CD147- and CD98-knocked down Jurkat T cells, which suggested that decreased CD147- and/or CD98-induced homotypic T cell aggregation and aggregation-inhibited chemotaxis might be associated with these signaling pathways. A role for CD147 in cell aggregation and chemotaxis was further indicated in primary CD4(+) T cells. Similarly, low expression of CD147 in primary T cells induced prominent cell aggregation and this aggregation attenuated primary T cell chemotactic ability in response to CypA. Our results have demonstrated the correlation between homotypic cell aggregation and the chemotactic response of T cells to CypA, and these data indicate that CD147 and CD98 might play important roles in cyclophilin-induced cell migration.

CD147 expression in human gastric cancer is associated with tumor recurrence and prognosis

CD147 is correlated with tumor aggressiveness in various human malignancies. Here, we investigated CD147 protein expression in 223 patients with gastric cancer by immunohistochemistry and analyzed its association with disease-free and overall survival. CD147 was increased in gastric cancer compared to normal tissues. Additionally, CD147 expression was associated with gastric cancer invasion, metastasis and TNM stage, whereas it was not related to age, sex, differentiation status, tumor site or Lauren classification. Kaplan-Meier analysis confirmed that CD147 was associated with disease-free and overall survival in patients with gastric cancer; i.e., patients with positive CD147 staining tend to have worse disease-free and overall survival. Moreover, Cox's proportional hazards analysis demonstrated that CD147 was an independent marker of disease-free and overall survival for patients with gastric cancer. These results confirm the association of CD147 with gastric cancer invasion and metastasis and prove that CD147 might be an indicator of tumor recurrence and prognosis in gastric cancer.

A regulatory loop involving miR-22, Sp1, and c-Myc modulates CD147 expression in breast cancer invasion and metastasis

Breast cancer is the most common cancer in women for which the metastatic process is still poorly understood. CD147 is upregulated in breast cancer and has been associated with tumor progression, but little is known about its regulatory mechanisms. In this study, we demonstrated that CD147 was overexpressed in breast cancer tissues and cell lines, and the high expression correlated with tumor invasion and metastasis. We also found that the transcription factors Sp1 and c-Myc could bind to the CD147 promoter and enhance its expression. The CD147 mRNA has a 748-bp 3'-untranslated region (UTR) with many miRNA target sites, suggesting possible regulation by miRNAs. We discovered that miR-22 repressed CD147 expression by directly targeting the CD147 3'UTR. We also determined that miR-22 could indirectly participate in CD147 modulation by downregulating Sp1 expression. miR-22 could form an autoregulatory loop with Sp1, which repressed miR-22 transcription by binding to the miR-22 promoter. Together with the c-Myc-mediated inhibition of miR-22 expression, our investigation identified a miR-22/Sp1/c-Myc network that regulates CD147 gene transcription. In addition, miR-22 overexpression suppressed breast cancer cell invasion, metastasis, and proliferation by targeting CD147 in vitro and in vivo. Furthermore, we found that miR-22 was significantly downregulated in breast cancer tissues and that its expression was inversely correlated with the tumor-node-metastasis stage and lymphatic metastasis in patients. Our study provides the first evidence that an miR-22/Sp1/c-Myc network regulates CD147 upregulation in breast cancer and that miR-22 represses breast cancer invasive and metastatic capacities.

Human rhomboid family-1 suppresses oxygen-independent degradation of hypoxia-inducible factor-1α in breast cancer

Intermittent oxygen deficiency in cancers promotes prolonged inflammation, continuous angiogenesis, and increased drug resistance. Hypoxia-inducible factor-1 (HIF1) has a pivotal role in the regulation of cellular responses to oxygen deficiency. The α-subunit of HIF1 (HIF1α) is degraded in normoxia but stabilized in hypoxia. However, the molecular mechanism that controls oxygen-independent degradation of HIF1α has remained elusive. Human rhomboid family-1 (RHBDF1) is a member of a large family of nonprotease rhomboids whose function is basically unknown. We report here that RHBDF1 expression in breast cancer is highly elevated and is strongly correlated with escalated disease progression, metastasis, poor prognosis, and poor response to chemotherapy. We show that RHBDF1 interaction with the receptor of activated protein-C kinase-1 (RACK1) in breast cancer cells prevents RACK1-assisted, oxygen-independent HIF1α degradation. In addition, we show that the HIF1α-stabilizing activity of RHBDF1 diminishes when the phosphorylation of a tyrosine residue on the RHBDF1 molecule is inhibited. These findings are consistent with the view that RHBDF1 is a critical component of a molecular switch that regulates HIF1α stability in cancer cells in hypoxia and that RHBDF1 is of potential value as a new target for cancer treatment.

Proteome profiling of neuroblastoma-derived exosomes reveal the expression of proteins potentially involved in tumor progression

Neuroblastoma (NB) is the most common extracranial solid tumor in childhood, with grim prognosis in a half of patients. Exosomes are nanometer-sized membrane vesicles derived from the multivesicular bodies (MVBs) of the endocytic pathway and released by normal and neoplastic cells. Tumor-derived exosomes have been shown in different model systems to carry molecules that promote cancer growth and dissemination. In this respect, we have here performed the first characterization and proteomic analysis of exosomes isolated from human NB cell lines by filtration and ultracentrifugation. Electron microscopy demonstrated that NB-derived exosomes exhibited the characteristic cup-shaped morphology. Dynamic light scattering studies showed a bell-shaped curve and a polydispersity factor consistent with those of exosomes. Zeta potential values suggested a good nanoparticle stability. We performed proteomic analysis of NB-derived exosomes by two dimension liquid chromatography separation and mass spectrometry analyses using the multidimensional protein identification technology strategy. We found that the large majority of the proteins identified in NB derived exosomes are present in Exocarta database including tetraspanins, fibronectin, heat shock proteins, MVB proteins, cytoskeleton-related proteins, prominin-1 (CD133), basigin (CD147) and B7-H3 (CD276). Expression of the CD9, CD63 and CD81 tetraspanins, fibronectin, CD133, CD147 and CD276 was validated by flow cytometry. Noteworthy, flow cytometric analysis showed that NB-derived exosomes expressed the GD2 disialoganglioside, the most specific marker of NB. In conclusion, this study shows that NB-derived exosomes express a discrete set of molecules involved in defense response, cell differentiation, cell proliferation and regulation of other important biological process. Thus, NB-derived exosomes may play an important role in the modulation of tumor microenvironment and represent potential tumor biomarkers.

Expression of HAb18G in non-small lung cancer and characterization of activation, migration, proliferation, and apoptosis in A549 cells following siRNA-induced downregulation of HAb18G

HAb18G, a novel cancer biomarker, has been shown to be involved in the progression of malignancy by regulating expression of vascular endothelial growth factor (VEGF) and matrixmetalloproteinases (MMPs). The goal of this study was to evaluate the role of HAb18G in the biology of NSCLC and to determine its potential as a therapeutic target. HAb18G protein expression was detected by immunohistochemistry in 150 NSCLC tissues. The results showed that HAb18G protein expression was associated with tumor diameter, lymph node status, tumor stage, and poor prognosis (P < 0.05). Multivariate analysis showed that HAb18G overexpression was an independent prognostic factor (HR, 3.713; 95 % CI, 1.114-12.373; P = 0.033). Transient infection of A549 lung cancer cells with small interfering RNA (SiRNA) against HAb18G efficiently inhibited the expression of HAb18G in A549 lung cancer cells at both mRNA and protein levels. Downregulation of HAb18G not only reduced MMP-2, MMP-9, and VEGF at mRNA and protein levels in A549 cells, but also inhibited fibroblasts to secrete MMP-2 and MMP-9 at mRNA level. Additionally, downregulation of HAb18G mRNA resulted in decreased migration, proliferation, and increased apoptosis of A549 in vitro. Our findings suggest that HAb18G overexpression plays an important role in progression of NSCLC and HAb18G may be a potential target of NSCLC therapy.

Prognostic significance of CD147 in patients with glioblastoma

CD147, also known as extracellular matrix metalloproteinase inducer, is a widely distributed cell surface glycoprotein that belongs to the immunoglobulin superfamily. CD147 has been proved to be enriched on the surface of many tumor cells, promoting tumor growth, invasion and metastasis by its stimulation effect on adjacent fibroblasts to produce matrix metalloproteinases. In this study, we aimed to explore the expression pattern of CD147 in glioblastoma (GBM) and investigate whether it could be used to assess subsequent prognosis of patients. For that, we recruited a total of 206 patients with pathologically confirmed GBM and 36 normal control brain tissue specimens. The expression of CD147 in GBM and normal tissues was investigated by immunohistochemistry assay. Genetic factors including MGMT and IDH1 mutation were also investigated to justify the prognostic significance of CD147. Results showed that CD147 expression was increased in GBM compared with that in normal tissues. Kaplan-Meier analysis showed that increased CD147 expression was associated with poor overall survival of patients with GBM. Moreover, Cox's proportional hazards model revealed that CD147 expression was an independent and significant prognostic marker of overall survival in GBM patients. These results proved that CD147 expression was relatively abundant in GBM and can be potentially used to predict prognosis and treatment response in GBM patients.

CD147, CD44, and the epidermal growth factor receptor (EGFR) signaling pathway cooperate to regulate breast epithelial cell invasiveness

The immunoglobulin superfamily glycoprotein CD147 (emmprin; basigin) is associated with an invasive phenotype in various types of cancers, including malignant breast cancer. We showed recently that up-regulation of CD147 in non-transformed, non-invasive breast epithelial cells is sufficient to induce an invasive phenotype characterized by membrane type-1 matrix metalloproteinase (MT1-MMP)-dependent invadopodia activity (Grass, G. D., Bratoeva, M., and Toole, B. P. (2012) Regulation of invadopodia formation and activity by CD147. J. Cell Sci. 125, 777-788). Here we found that CD147 induces breast epithelial cell invasiveness by promoting epidermal growth factor receptor (EGFR)-Ras-ERK signaling in a manner dependent on hyaluronan-CD44 interaction. Furthermore, CD147 promotes assembly of signaling complexes containing CD147, CD44, and EGFR in lipid raftlike domains. We also found that oncogenic Ras regulates CD147 expression, hyaluronan synthesis, and formation of CD147-CD44-EGFR complexes, thus forming a positive feedback loop that may amplify invasiveness. Last, we showed that malignant breast cancer cells are heterogeneous in their expression of surface-associated CD147 and that high levels of membrane CD147 correlate with cell surface EGFR and CD44 levels, activated EGFR and ERK1, and activated invadopodia. Future studies should evaluate CD147 as a potential therapeutic target and disease stratification marker in breast cancer.

Epitope mapping of metuximab on CD147 using phage display and molecular docking

Metuximab is the generic name of Licartin, a new drug for radioimmunotherapy of hepatocellular carcinoma. Although it is known to be a mouse monoclonal antibody against CD147, the complete epitope mediating the binding of metuximab to CD147 remains unknown. We panned the Ph.D.-12 phage display peptide library against metuximab and got six mimotopes. The following bioinformatics analysis based on mimotopes suggested that metuximab recognizes a conformational epitope composed of more than 20 residues. The residues of its epitope may include T28, V30, K36, L38, K57, F74, D77, S78, D79, D80, Q81, G83, S86, N98, Q100, L101, H102, G103, P104, V131, P132, and K191. The homology modeling of metuximab and the docking of CD147 to metuximab were also performed. Based on the top one docking model, the epitope was predicted to contain 28 residues: AGTVFTTV (23–30), I37, D45, E84, V88, EPMGTANIQLH (92–102), VPP (131–133), Q164, and K191. Almost half of the residues predicted on the basis of mimotope analysis also appear in the docking result, indicating that both results are reliable. As the predicted epitopes of metuximab largely overlap with interfaces of CD147-CD147 interactions, a structural mechanism of metuximab is proposed as blocking the formation of CD147 dimer.

CD147 mediates chemoresistance in breast cancer via ABCG2 by affecting its cellular localization and dimerization

CD147 and ABCG2 both have been reported to mediate Multidrug resistance (MDR) in breast cancer. Recent study demonstrates that CD147 could form a complex with ABCG2 on the cell membrane in primary effusion lymphoma. However, whether these two molecules regulate each other in breast cancer and result in MDR is not clear. We established four MCF-7 cell lines transfected with CD147 and/or ABCG2 and found that CD147 could increase the expression and dimerization of ABCG2, affect its cellular localization and regulate its drug transporter function. The findings derived from cells were confirmed subsequently in clinic samples of chemotherapy-sensitive/resistant breast 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.

EMMPRIN is an independent negative prognostic factor for patients with astrocytic glioma

Extracellular matrix metalloproteinase inducer (EMMPRIN), also known as CD147, is a member of the immunoglobulin superfamily that is present on the surface of tumor cells and stimulates adjacent fibroblasts to produce matrix metalloproteinases (MMPs). It has been proved to be associated with tumor invasion and metastasis in various human malignancies. In our study, the protein expression level of EMMPRIN in 306 cases of astrocytic glioma is investigated by immunohistochemistry assay. Statistical analysis was utilized to evaluate the association of EMMPRIN with clinicopathological characteristics and prognosis of patients. It was proved that EMMPRIN protein expression was increased in glioma compared with that in normal brain tissue. Moreover, EMMPRIN immunohistochemical staining was correlated with WHO grade and Karnofsky performance score for strong positive EMMPRIN staining is more frequently detected in glioma of advanced grade or low KPS score. It is also demonstrated that EMMPRIN could be an independent negative prognostic factor in glioma for patients with glioma of strong EMMPRIN staining tend to have high risk of death. These results proved that EMMPRIN is associated with prognosis of glioma, which may also suggest the potential role of EMMPRIN in glioma management.

EMMPRIN/CD147 expression is associated with disease-free survival of patients with colorectal cancer

EMMPRIN/CD147 has been proved to be associated with tumor invasion and metastasis in various human malignancies. In the present study, we investigated the expression of CD147 and its association with disease-free survival of colorectal cancer patients. CD147 expression was investigated in 328 cases of colorectal cancer by immunohistochemistry assay. Statistical analysis was utilized to evaluate the association of CD147 expression with disease-free survival of colorectal cancer patients. CD147 expression was proved to be increased in colorectal cancer (P < 0.001) and related to tumor invasion (P < 0.001), metastasis (P < 0.001), and TNM stage (P < 0.001). Kaplan-Meier showed CD147 was associated with disease-free survival of patients with colorectal cancer for patients with higher CD147 expression tend to have shorter disease-free survival (P < 0.001). Multivariate analysis also proved CD147 to be an independent prognostic factor for disease-free survival of colorectal cancer patients (P < 0.05). These results suggested the potential role of CD147 in relapse of human colorectal cancer. It might be a novel molecular marker to predict relapse of patients with colorectal cancer.

CD147 induces UPR to inhibit apoptosis and chemosensitivity by increasing the transcription of Bip in hepatocellular carcinoma

The unfolded protein response (UPR) is generally activated in solid tumors and results in tumor cell anti-apoptosis and drug resistance. However, tumor-specific UPR transducers are largely unknown. In the present study, we identified CD147, a cancer biomarker, as an UPR inducer in hepatocellular carcinoma (HCC). The expression of the major UPR target, Bip, was found to be positively associated with CD147 in human hepatoma tissues. By phosphorylating FAK and Src, CD147-enhanced TFII-I tyrosine phosphorylation at Tyr248. CD147 also induced p-TFII-I nuclear localization and binding to the Bip promoter where endoplasmic reticulum (ER) stress response element 1 (ERSE1) (-82/-50) is the most efficient target of the three ERSEs, thus increasing transcription of Bip. Furthermore, by inducing UPR, CD147 inhibited HCC cell apoptosis and decreased cell Adriamycin chemosensitivity, thus decreasing the survival rate of hepatoma-bearing nude mice. Together, these results reveal pivotal roles for CD147 in modulating the UPR in HCC and raise the possibility that CD147 is a target that promotes HCC cell apoptosis and increases the sensitivity of tumors to anti-cancer drugs. Therefore, CD147 inhibition provides an opportunity to enhance the efficacy of existing agents and represents a novel target for HCC treatment.

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.

HAb18G/CD147 promotes epithelial-mesenchymal transition through TGF-β signaling and is transcriptionally regulated by Slug

Epithelial-mesenchymal transition (EMT) induced by transforming growth factor-β (TGF-β) is implicated in hepatocarcinogenesis and hepatocellular carcinoma (HCC) metastasis. HAb18G/CD147, which belongs to the CD147 family, is an HCC-associated antigen that has a crucial role in tumor invasion and metastasis. The goal of this study was to investigate the role of HAb18G/CD147 during EMT in hepatocarcinogenesis. Human normal hepatic cell lines QZG and L02, primary mouse hepatocytes and nude mouse models were used to determine the role of HAb18G/CD147 in EMT, and the involvement of the TGF-β-driven pathway. A dual-luciferase reporter assay and ChIP were used to investigate the transcriptional regulation of the CD147 gene. Samples from patients with liver disease were assessed to determine the relationship between HAb18G/CD147 and typical markers for EMT. Our results show that upregulation of HAb18G/CD147 is induced by TGF-β coupled with downregulation of E-cadherin and upregulation of N-cadherin and vimentin. The expression of HAb18G/CD147 is controlled by the cell survival PI3K/Akt/GSK3β signaling pathway, and is directly regulated by the transcription factor Slug. Transfection of CD147 also induces an elevated expression of TGF-β. CD147-transfected hepatocytes have mesenchymal phenotypes that accelerate tumor formation and tumor metastasis in vivo. Immunohistochemistry analysis shows a negative correlation between HAb18G/CD147 and E-cadherin expression (r(s)=-0.3622, P=0.0105), and a positive correlation between HAb18G/CD147 and Slug expression (r(s)=0.3064, P=0.0323) in human HCC tissues. Our study uncovers a novel role of HAb18G/CD147 in mediating EMT in the process of HCC progression and showed that CD147 is a Slug target gene in the signaling cascade TGF-β→PI3K/Akt→GSK3β→Snail→Slug→CD147. Our results suggest that CD147 may be a potential target for the treatment and prevention of HCC.