TIE1 promotes cervical cancer progression via Basigin-matrix metalloproteinase axis.

Background: Tyrosine kinase with immunoglobulin and EGF-like domains 1 (TIE1) is known as an orphan receptor prominently expressed in endothelial cells and participates in angiogenesis by regulating TIE2 activity. Our previous study demonstrated elevated TIE1 expression in cervical cancer cells. However, the role of TIE1 in cervical cancer progression, metastasis and treatment remains elusive. Methods: Immunohistochemistry staining for TIE1 and Basigin was performed in 135 human cervical cancer tissues. Overexpressing vectors and siRNAs were used to manipulate gene expression in tumor cells. Colony formation, wound healing, and transwell assays were used to assess cervical cancer cell proliferation and migration in vitro. Subcutaneous xenograft tumor and lung metastasis mouse models were established to examine tumor growth and metastasis. Co-Immunoprecipitation and Mass Spectrometry were applied to explore the proteins binding to TIE1. Immunoprecipitation and immunofluorescence staining were used to verify the interaction between TIE1 and Basigin. Cycloheximide chase assay and MG132 treatment were conducted to analyze protein stability. Results: High TIE1 expression was associated with poor survival in cervical cancer patients. TIE1 overexpression promoted the proliferation, migration and invasion of cervical cancer cells in vitro, as well as tumor growth and metastasis in vivo. In addition, Basigin, a transmembrane glycoprotein, was identified as a TIE1 binding protein, suggesting a pivotal role in matrix metalloproteinase regulation, angiogenesis, cell adhesion, and immune responses. Knockdown of Basigin or treatment with the Basigin inhibitor AC-73 reversed the tumor-promoting effect of TIE1 in vitro and in vivo. Furthermore, we found that TIE1 was able to interact with and stabilize the Basigin protein and stimulate the Basigin-matrix metalloproteinase axis. Conclusion: TIE1 expression in cervical cells exerts a tumor-promoting effect, which is at least in part dependent on its interaction with Basigin. These findings have revealed a TIE2-independent mechanism of TIE1, which may provide a new biomarker for cervical cancer progression, and a potential therapeutic target for the treatment of cervical cancer patients.

Thai traditional medicines reduce CD147 levels in lung cells: Potential therapeutic candidates for cancers, inflammations, and COVID-19.

ETHNOPHARMACOLOGICAL RELEVANCE: The cluster of differentiation 147 (CD147) is identified as the signaling protein relevant importantly in various cancers, inflammations, and coronavirus disease 2019 (COVID-19) via interacting with extracellular cyclophilin A (CypA). The reduction of CD147 levels inhibits the progression of CD147-associated diseases. Thai traditional medicines (TTMs): Keaw-hom (KH), Um-ma-ruek-ka-wa-tee (UM), Chan-ta-lee-la (CT), and Ha-rak (HR) have been used as anti-pyretic and anti-respiratory syndromes caused from various conditions including cancers, inflammations, and infections. Thus, these medicines would play a crucial role in the reduction of CD147 levels. AIM OF THE STUDY: This article aimed to investigate the effects of KH, UM, CT, and HR for reducing the CD147 levels through in vitro study. Additionally, in silico study was employed to screen the active compounds reflexing the reduction of CD147 levels. MATERIALS AND METHODS: The immunofluorescent technique was used to evaluate the reduction of CD147 levels in human lung epithelial cells (BEAS-2B) stimulated with CypA for eight extracts of KH, UM, CT, and HR obtained from water decoction (D) and 70% ethanol maceration (M) including, KHD, UMD, CTD, HRD, KHM, UMM, CTM, and HRM. RESULTS: UM extracts showed the most efficiency for reduction of CD147 levels in the cytoplasm and perinuclear of BEAS-2B cells stimulated with CypA. Phenolic compounds composing polyphenols, polyphenol sugars, and flavonoids were identified as the major chemical components of UMD and UMM. Further, molecular docking calculations identified polyphenol sugars as CypA inhibitors. CONCLUSIONS: UMD and UMM are potential for reduction of CD147 levels which provide a useful information for further development of UM as potential therapeutic candidates for CD147-associated diseases such as cancers, inflammations, and COVID-19.

The role of the C-terminal tail region as a plug to regulate XKR8 lipid scramblase.

XK-related 8 (XKR8), in complex with the transmembrane glycoprotein basigin, functions as a phospholipid scramblase activated by the caspase-mediated cleavage or phosphorylation of its C-terminal tail. It carries a putative phospholipid translocation path of multiple hydrophobic and charged residues in the transmembrane region. It also has a crucial tryptophan at the exoplasmic end of the path that regulates its scrambling activity. We herein investigated the tertiary structure of the human XKR8-basigin complex embedded in lipid nanodiscs at an overall resolution of 3.66 Å. We found that the C-terminal tail engaged in intricate polar and van der Waals interactions with a groove at the cytoplasmic surface of XKR8. These interactions maintained the inactive state of XKR8. Point mutations to disrupt these interactions strongly enhanced the scrambling activity of XKR8, suggesting that the activation of XKR8 is mediated by releasing the C-terminal tail from the cytoplasmic groove. We speculate that the cytoplasmic tail region of XKR8 functions as a plug to prevent the scrambling of phospholipids.

Soluble CD147 regulates endostatin via its effects on the activities of MMP-9 and secreted proteasome 20S.

During progression of rheumatoid arthritis (RA), angiogenesis provides oxygen and nutrients for the cells' increased metabolic demands and number. To turn on angiogenesis, pro-angiogenic factors must outweigh anti-angiogenic factors. We have previously shown that CD147/extracellular matrix metalloproteinase inducer (EMMPRIN) can induce the expression of the pro-angiogenic factors vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP-9) in a co-culture of the human HT1080 fibrosarcoma and U937 monocytic-like cell lines. However, whether CD147 influences anti-angiogenic factors was not known. We now show that relative to single cultures, the co-culture of these cells not only enhanced pro-angiogenic factors but also decreased the anti-angiogenic factors endostatin and thrombospondin-1 (Tsp-1), generally increasing the angiogenic potential as measured by a wound assay. Using anti-CD147 antibody, CD147 small interfering RNA (siRNA), and recombinant CD147, we demonstrate that CD147 hormetically regulates the generation of endostatin but has no effect on Tsp-1. Since endostatin is cleaved from collagen XVIII (Col18A), we applied different protease inhibitors and established that MMP-9 and proteasome 20S, but not cathepsins, are responsible for endostatin generation. MMP-9 and proteasome 20S collaborate to synergistically enhance endostatin generation, and in a non-cellular system, CD147 enhanced MMP-9 activity and hormetically regulated proteasome 20S activity. Serum samples obtained from RA patients and healthy controls mostly corroborated these findings, indicating clinical relevance. Cumulatively, these findings suggest that secreted CD147 mediates a possibly allosteric effect on MMP-9 and proteasome 20S activities and can serve as a switch that turns angiogenesis on or off, depending on its ambient concentrations in the microenvironment.

Targeting cancer-derived extracellular vesicles by combining CD147 inhibition with tissue factor pathway inhibitor for the management of urothelial cancer cells.

BACKGROUND: Extracellular vesicles (EVs), including microvesicles, hold promise for the management of bladder urothelial carcinoma (BLCA), particularly because of their utility in identifying therapeutic targets and their diagnostic potential using easily accessible urine samples. Among the transmembrane glycoproteins highly enriched in cancer-derived EVs, tissue factor (TF) and CD147 have been implicated in promoting tumor progression. In this in vitro study, we explored a novel approach to impede cancer cell migration and metastasis by simultaneously targeting these molecules on urothelial cancer-derived EVs. METHODS: Cell culture supernatants from invasive and non-invasive bladder cancer cell lines and urine samples from patients with BLCA were collected. Large, microvesicle-like EVs were isolated using sequential centrifugation and characterized by electron microscopy, nanoparticle tracking analysis, and flow cytometry. The impact of urinary or cell supernatant-derived EVs on cellular phenotypes was evaluated using cell-based assays following combined treatment with a specific CD147 inhibitor alone or in combination with a tissue factor pathway inhibitor (TFPI), an endogenous anticoagulant protein that can be released by low-molecular-weight heparins. RESULTS: We observed that EVs obtained from the urine samples of patients with muscle-invasive BLCA and from the aggressive bladder cancer cell line J82 exhibited higher TF activity and CD147 expression levels than did their non-invasive counterparts. The shedding of GFP-tagged CD147 into isolated vesicles demonstrated that the vesicles originated from plasma cell membranes. EVs originating from invasive cancer cells were found to trigger migration, secretion of matrix metalloproteinases (MMPs), and invasion. The same induction of MMP activity was replicated using EVs obtained from urine samples of patients with invasive BLCA. EVs derived from cancer cell clones overexpressing TF and CD147 were produced in higher quantities and exhibited a higher invasive potential than those from control cancer cells. TFPI interfered with the effect when used in conjunction with the CD147 inhibitor, further suppressing homotypic EV-induced migration, MMP production, and invasion. CONCLUSIONS: Our findings suggest that combining a CD147 inhibitor with low molecular weight heparins to induce TFPI release may be a promising therapeutic approach for urothelial cancer management. This combination can potentially suppress the tumor-promoting actions of cancer-derived microvesicle-like EVs, including collective matrix invasion.

Small particles or vesicles released by cancer cells into their surroundings have the potential to stimulate the spread and growth of cancer cells. In this study, we focused on two specific molecules presented by these cancer cell-derived vesicles that could play a role in promoting the dissemination of cancer cells: a protein related to blood clotting and a protein on the cell surface.We found that large vesicles from bladder cancer cells that have the ability to spread had higher levels of these proteins than vesicles from nonspreading cancer cells. We also found that the former could make cancer cells move about more, produce more of a substance that helps cancer cells spread, and invade other tissues.To counteract the cancer-promoting actions of these vesicles, we examined the impact of combining a naturally occurring anticlotting protein that can be released by medications derived from heparin with an inhibitor targeting the cancer cell surface protein. We found that this combination stopped the vesicles from helping cancer cells move about more, produce more of the spreading substance, and invade other tissues.This approach of simultaneously targeting the two protein molecules present on cancer cell-derived vesicles might be a new way to treat bladder cancer.

NOS3 prevents MMP-9, and MMP-13 induced extracellular matrix proteolytic degradation through specific microRNA-targeted expression of extracellular matrix metalloproteinase inducer in hypertension-related atherosclerosis.

BACKGROUND: Endothelial nitric oxide synthase (NOS3) elicits atheroprotection by preventing extracellular matrix (ECM) proteolytic degradation through inhibition of extracellular matrix metalloproteinase inducer (EMMPRIN) and collagenase MMP-13 by still unknown mechanisms. METHODS: C57BL/6 mice lacking ApoE , NOS3, and/or MMP13 were fed with a high-fat diet for 6 weeks. Entire aortas were extracted and frozen to analyze protein and nucleic acid expression. Atherosclerotic plaques were detected by ultrasound imaging, Oil Red O (ORO) staining, and Western Blot. RNA-seq and RT-qPCR were performed to evaluate EMMPRIN, MMP-9, and EMMPRIN-targeting miRNAs. Mouse aortic endothelial cells (MAEC) were incubated to assess the role of active MMP-13 over MMP-9. One-way ANOVA or Kruskal-Wallis tests were performed to determine statistical differences. RESULTS: Lack of NOS3 in ApoE null mice fed with a high-fat diet increased severe plaque accumulation, vessel wall widening, and high mortality, along with EMMPRIN-induced expression by upregulation of miRNAs 46a-5p and 486-5p. However, knocking out MMP-13 in ApoE/NOS3 -deficient mice was sufficient to prevent mortality (66.6 vs. 26.6%), plaque progression (23.1 vs. 8.8%), and MMP-9 expression, as confirmed in murine aortic endothelial cell (MAEC) cultures, in which MMP-9 was upregulated by incubation with active recombinant MMP-13, suggesting MMP-9 as a new target of MMP-13 in atherosclerosis. CONCLUSION: We describe a novel mechanism by which the absence of NOS3 may worsen atherosclerosis through EMMPRIN-induced ECM proteolytic degradation by targeting the expression of miRNAs 146a-5p and 485-5p. Focusing on NOS3 regulation of ECM degradation could be a promising approach in the management of atherosclerosis.

Basigin mediation of Plasmodium falciparum red blood cell invasion does not require its transmembrane domain or interaction with monocarboxylate transporter 1.

Plasmodium falciparum invasion of the red blood cell is reliant upon the essential interaction of PfRh5 with the host receptor protein basigin. Basigin exists as part of one or more multiprotein complexes, most notably through interaction with the monocarboxylate transporter MCT1. However, the potential requirement for basigin association with MCT1 and the wider role of basigin host membrane context and lateral protein associations during merozoite invasion has not been established. Using genetically manipulated in vitro derived reticulocytes, we demonstrate the ability to uncouple basigin ectodomain presentation from its transmembrane domain-mediated interactions, including with MCT1. Merozoite invasion of reticulocytes is unaffected by disruption of basigin-MCT1 interaction and by removal or replacement of the basigin transmembrane helix. Therefore, presentation of the basigin ectodomain at the red blood cell surface, independent of its native association with MCT1 or other interactions mediated by the transmembrane domain, is sufficient to facilitate merozoite invasion.

Myricetin, a natural inhibitor of CD147, increases sensitivity of cisplatin in ovarian cancer.

BACKGROUND: Ovarian cancer (OC) is the most lethal gynecological tumor, but it currently lacks effective therapeutic targets. CD147, which is overexpressed in OC, plays a crucial role in promoting malignant progression and is associated with poor prognosis in patients. Therefore, CD147 has been identified as a potential therapeutic target. However, there is a limited amount of research on the development of CD147 inhibitors. METHODS: Surface plasmon resonance (SPR) assay and virtual molecular docking analysis were performed to identify potential natural compounds targeting CD147. The anti­tumor effects of myricetin were evaluated using various assays, including CCK8, Alkaline comet, immunofluorescence and xenograft mouse models. The underlying mechanism was investigated through western blot analysis and lentivirus short hairpin RNA (LV-shRNA) transfection. RESULTS: Myricetin, a flavonoid commonly found in plants, was discovered to be a potent inhibitor of CD147. Our findings demonstrated that myricetin exhibited a strong affinity for CD147 and down-regulated the protein level of CD147 by facilitating its proteasome-dependent degradation. Additionally, we observed synergistic antitumor effects of myricetin and cisplatin both in vivo and in vitro. Mechanistically, myricetin suppressed the expression of FOXM1 and its downstream DNA damage response (DDR) genes E×O1and BRIP1, thereby enhancing the DDR induced by cisplatin. CONCLUSION: Our data demonstrate that myricetin, a natural inhibitor of CD147, may have clinical utility in the treatment of OC due to its ability to increase genomic toxicity when combined with cisplatin.

Studies on the effect and mechanism of CD147 on melanoma stem cells

Background: Melanoma is the most aggressive form of skin cancer. Melanoma stem cells (MSCs) are one of the driving forces of melanoma invasion and metastasis. Therefore, it is of great significance to explore the mechanisms that maintain the stemness of MSCs. In this study, CD147-positive (CD147+) MSCs derived from A375 cell line were characterized. Methods: Side population (SP) and non-SP cells were sorted from A375 cells. Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of CD147 in SP and non-SP cells. Subsequently, CD147+ and CD147-negative (CD147-) cells were isolated from SP cells. Stem cell characteristics and metastatic potential of CD147+/- antigen-presenting cells were identified by sphere-forming, wound-healing, and transwell assays. Western blot analysis was performed to evaluate the protein levels of transforming growth factor-beta1 (TGFβ1) and neurogenic locus notch homolog protein 1 (Notch1) signaling pathway. Xenograft tumor experiments were conducted to investigate the tumorigenic capacity of CD147+ cells in vivo. Results: CD147 was highly expressed in SP cells of A375 cell line. CD147+ cells have stronger abilities for sphere forming, migration, and invasion in vitro. The protein levels of TGFβ1, notch1, jagged1, and Hes1 were higher in CD147+ cells than in CD147- cells. Moreover, the CD147+ cells showed stronger tumorigenic and metastatic potential in vivo. Conclusion: SP cells of A375 cell line expressed high levels of CD147, and CD147+ SP cells possessed much stronger stem-like characteristics and motility, which is linked to the activation of TGFβ and notch pathways (AU)

Potential Alternative Receptors for SARS-CoV-2-Induced Kidney Damage: TLR-4, KIM-1/TIM-1, and CD147.

Kidney damage in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can occur even in patients with no underlying kidney disease. Signs of kidney problems can progress to a state that demands dialysis and hampering recovery. Although not without controversy, emerging evidence implicates direct infectivity of SARS-CoV-2 in the kidney. At the early stage of the pandemic, consideration was mainly on the well-recognized angiotensin-converting enzyme 2 (ACE2) receptor as being the site for viral interaction and subsequent cellular internalization. Despite the abundance of ACE2 receptors in the kidneys, researchers have expanded beyond ACE2 and identified novel viral entry pathways that could be advantageously explored as therapeutic targets. This review presents the potential involvement of toll-like receptor 4 (TLR-4), kidney injury molecule-1/T cell immunoglobulin mucin domain 1 (KIM-1/TIM-1), and cluster of differentiation 147 (CD147) in SARS-CoV-2-associated renal damage. In this context, we address the unresolved issues surrounding SARS-CoV-2 renal infectivity.

Cyclophilin A is a ligand for RAGE in thrombo-inflammation.

AIMS: Cyclophilin A (CyPA) induces leucocyte recruitment and platelet activation upon release into the extracellular space. Extracellular CyPA therefore plays a critical role in immuno-inflammatory responses in tissue injury and thrombosis upon platelet activation. To date, CD147 (EMMPRIN) has been described as the primary receptor mediating extracellular effects of CyPA in platelets and leucocytes. The receptor for advanced glycation end products (RAGE) shares inflammatory and prothrombotic properties and has also been found to have similar ligands as CD147. In this study, we investigated the role of RAGE as a previously unknown interaction partner for CyPA. METHODS AND RESULTS: Confocal imaging, proximity ligation, co-immunoprecipitation, and atomic force microscopy were performed and demonstrated an interaction of CyPA with RAGE on the cell surface. Static and dynamic cell adhesion and chemotaxis assays towards extracellular CyPA using human leucocytes and leucocytes from RAGE-deficient Ager-/- mice were conducted. Inhibition of RAGE abrogated CyPA-induced effects on leucocyte adhesion and chemotaxis in vitro. Accordingly, Ager-/- mice showed reduced leucocyte recruitment and endothelial adhesion towards CyPA in vivo. In wild-type mice, we observed a downregulation of RAGE on leucocytes when endogenous extracellular CyPA was reduced. We furthermore evaluated the role of RAGE for platelet activation and thrombus formation upon CyPA stimulation. CyPA-induced activation of platelets was found to be dependent on RAGE, as inhibition of RAGE, as well as platelets from Ager-/- mice showed a diminished activation and thrombus formation upon CyPA stimulation. CyPA-induced signalling through RAGE was found to involve central signalling pathways including the adaptor protein MyD88, intracellular Ca2+ signalling, and NF-κB activation. CONCLUSION: We propose RAGE as a hitherto unknown receptor for CyPA mediating leucocyte as well as platelet activation. The CyPA-RAGE interaction thus represents a novel mechanism in thrombo-inflammation.

CD147 induces asthmatic airway remodeling and activation of circulating fibrocytes in a mouse model of asthma.

BACKGROUND: Airway remodeling is a poorly reversible feature of asthma which lacks effective therapeutic interventions. CD147 can regulate extracellular matrix (ECM) remodeling and tissue fibrosis, and participate in the pathogenesis of asthma. In this study, the role of CD147 in airway remodeling and activation of circulating fibrocytes was investigated in asthmatic mice. METHODS: Asthmatic mouse model was established by sensitizing and challenging mice with ovalbumin (OVA), and treated with anti-CD147 or Isotype antibody. The number of eosinophils in bronchoalveolar lavage fluid (BALF) was examined by microscope, and the levels of interleukin-4 (IL-4), IL-5 and IL-13 in BALF were detected by enzyme-linked immunosorbent assay (ELISA). The number of CD45+ and collagen I (COL-I)+ circulating fibrocytes in BALF was detected by flow cytometry. Lung tissue sections were respectively stained with hematoxylin and eosin (HE), periodic acid-Schiff (PAS) or Masson trichrome staining, or used for immunohistochemistry of CD31 and immunohistofluorescence of α-smooth muscle actin (α-SMA), CD45 and COL-I. The protein expression of α-SMA, vascular endothelial growth factor (VEGF), transforming growth factor-ß1 (TGF-ß1), Fibronectin, and COL-I was determined by western blotting. RESULTS: Anti-CD147 treatment significantly reduced the number of eosinophils and the levels of IL-4, IL-13, and IL-5 in BALF, and repressed airway inflammatory infiltration and airway wall thickening in asthmatic mice. Anti-CD147 treatment also reduced airway goblet cell metaplasia, collagen deposition, and angiogenesis in asthmatic mice, accompanied by inhibition of VEGF and α-SMA expression. The number of CD45+COL-I+ circulating fibrocytes was increased in BALF and lung tissues of OVA-induced asthmatic mice, but was decreased by anti-CD147 treatment. In addition, anti-CD147 treatment also reduced the protein expression of COL-I, fibronectin, and TGF-ß1 in lung tissues of asthmatic mice. CONCLUSION: OVA-triggered airway inflammation and airway remodeling in asthmatic mice can be repressed by anti-CD147 treatment, along with inhibiting the accumulation and activation of circulating fibrocytes.

Intervention with extracellular matrix metalloproteinase inducer in osteoclasts attenuates periodontitis-induced bone resorption.

Extracellular matrix metalloproteinase inducer (EMMPRIN) plays critical roles in the regulation of inflammation and bone metabolism. The roles of EMMPRIN signaling in osteoclasts are worthy of deep study. The present study aimed to investigate bone resorption in periodontitis through the intervention of EMMPRIN signaling. The distribution of EMMPRIN in human periodontitis was observed. RANKL-induced osteoclast differentiation of mouse bone marrow-derived macrophages (BMMs) were treated with EMMPRIN inhibitor in vitro. Rats with ligation-induced periodontitis were treated with EMMPRIN inhibitor and harvested for microcomputed tomography scanning, histologic observation, immunohistochemistry, and double immunofluorescence analysis. Positive expressions of EMMPRIN could be found in the CD68+-infiltrating cells. Downregulated EMMPRIN restrained osteoclast differentiation of BMMs in vitro, which also inhibited MMP-9 expression (*P < 0.05). In vivo, EMMPRIN inhibitor restrained ligation-induced bone resorption by decreasing tartrate-resistant acid phosphatase-positive osteoclasts. Both EMMPRIN-positive and MMP-9-positive osteoclasts were less common in the EMMPRIN inhibitor groups than in the control groups. Intervention of EMMPRIN signaling in osteoclasts could probably provide a potential therapeutic target for attenuating ligation-induced bone resorption.

Basigin Deficiency Induces Spontaneous Polycystic Kidney in Mice.

BACKGROUND: Polycystic kidney disease is the most common hereditary kidney disorder with early and frequent hypertension symptoms. The mechanisms of cyst progression in polycystic kidney disease remain incompletely understood. METHODS: Bsg (basigin) heterozygous and homozygous knockout mice were generated using cas9 system, and Bsg overexpression was achieved by adeno-associated virus serotype 9 injection. Renal morphology was investigated through histological and imaging analysis. Molecular analysis was performed through transcriptomic profiling and biochemical approaches. RESULTS: Bsg-deficient mice exhibited significantly elevated arterial blood pressure. Further investigation demonstrated that Bsg deficiency triggers spontaneous cystic formation in mouse kidneys, which shares similar cyst pathological features and common transcriptional regulatory pathways with human polycystic kidney disease. Moreover, Bsg disruption promoted polycystin-1 ubiquitination and degradation, leading to activation of polycystic kidney disease associated cAMP and AMPK signaling pathways in Bsg knockout mouse kidneys. Finally, adeno-associated virus serotype 9 mediated Bsg reexpression reversed cystic progression in Bsg knockout mice in vivo, and Bsg overexpression inhibited the expansion of Madin-Darby canine kidney cysts in vitro. CONCLUSIONS: Our findings show that Bsg deficiency leads to an early-onset spontaneous polycystic kidney phenotype, suggesting that dysregulated Bsg signaling may be a contributing factor in cystogenesis.

CD147 promotes breast cancer migration and invasion by inducing epithelial-mesenchymal transition via the MAPK/ERK signaling pathway.

BACKGROUND: CD147, a transmembrane glycoprotein, has been implicated in various cancer-related processes but its role in breast cancer remains poorly understood. Herein, we investigated the expression of CD147 in different breast cancer cell lines and explored its functional roles, including migration, invasion, drug resistance and modulation of key proteins associated with cancer progression. METHODS: The expression of CD147 was assessed in MCF-10 A, BT549, MDA-MB-231 and MCF-7 breast cancer cell lines using qRT-PCR and Western blotting, following which lyposome transfections were performed, leading overexpression of CD147 in BT549 cells and knockdown of CD147 in MCF-7 cells. Scratch assays and Transwell invasion and were performed to evaluate the cells' migration and invasion abilities. Sensitivity to 5-FU was determined via CCK-8 assays, and the expression of Snail1, E-cadherin, Vimentin, MMP-9 and the MAPK/ERK pathway were analyzed by qRT-PCR and Western blotting. RESULTS: Compared with normal beast epithelial cells, CD147 was highly expressed in all breast cancer cell lines, with the highest overexpression observed in MCF-7 cells and the lowest overexpression observed in BT549 cells. Overexpression of CD147 in BT549 cells increased, migration, invasion, viability and resistance to 5-FU of BT549 cells, while CD147 knockdown in MCF-7 cells reduced these properties of MCF-7 cells. Furthermore, CD147 influenced the expression of Snail1, Vimentin, E-cadherin, and MMP-9, suggesting its involvement in epithelial-mesenchymal transition (EMT) regulation. The MAPK/ERK pathway was activated by CD147 in BT549 cells, as indicated by increased p-MEK/MEK ratio and p-ERK/ERK ratio. In contrast, CD147 silencing in MCF-7 cells resulted in reduced p-MEK/MEK ratio and p-ERK/ERK ratio. CONCLUSION: In summary, our findings suggest CD147 as a potential therapeutic target in breast cancer treatment, particularly in cases where drug resistance and metastasis are concerns, worthy of further explorations.

CD147/Basigin Is Involved in the Development of Malignant Tumors and T-Cell-Mediated Immunological Disorders via Regulation of Glycolysis.

CD147/Basigin, a transmembrane glycoprotein belonging to the immunoglobulin superfamily, is a multifunctional molecule with various binding partners. CD147 binds to monocarboxylate transporters (MCTs) and supports their expression on plasma membranes. MTC-1 and MCT-4 export the lactic acid that is converted from pyruvate in glycolysis to maintain the intracellular pH level and a stable metabolic state. Under physiological conditions, cellular energy production is induced by mitochondrial oxidative phosphorylation. Glycolysis usually occurs under anaerobic conditions, whereas cancer cells depend on glycolysis under aerobic conditions. T cells also require glycolysis for differentiation, proliferation, and activation. Human malignant melanoma cells expressed higher levels of MCT-1 and MCT-4, co-localized with CD147 on the plasma membrane, and showed an increased glycolysis rate compared to normal human melanocytes. CD147 silencing by siRNA abrogated MCT-1 and MCT-4 membrane expression and disrupted glycolysis, inhibiting cancer cell activity. Furthermore, CD147 is involved in psoriasis. MCT-1 was absent on CD4+ T cells in CD147-deficient mice. The naïve CD4+ T cells from CD147-deficient mice exhibited a low capacity to differentiate into Th17 cells. Imiquimod-induced skin inflammation was significantly milder in the CD147-deficient mice than in the wild-type mice. Overall, CD147/Basigin is involved in the development of malignant tumors and T-cell-mediated immunological disorders via glycolysis regulation.

Extracellular matrix metalloproteinases inducer gene polymorphism and reduced serum matrix metalloprotease-2 activity in preeclampsia patients.

Preeclampsia increases the risk of pregnancy-related complications, nevertheless a successful spiral vessel remodeling, and trophoblast invasion reduces disorders of pregnancy. Matrix metalloproteinase-2 (MMP-2) clears the path for trophoblast invasion, and activation of MMP-2 largely depends on extracellular matrix metalloproteinases inducer (EMMPRIN) protein. This study aimed to investigate EMMPRIN gene polymorphism and MMP-2 activity in preeclampsia patients. Archival whole blood and serum samples of 74 preeclampsia and 66 normotensive pregnant women age-matched were used in this case-control study. Genomic DNA was extracted from the whole blood samples and EMMPRIN gene amplified with specific primers following fragments sequence mutation analysis. Serum MMP-2 activity was determined using enzyme-linked immunosorbent assay (ELISA) and socio-demographic data of participants retrieved from the database. Age of preeclampsia patients (32.78 ± 6.39) years and body mass index (BMI) (33.09 ± 7.27) kg/m2 compared with the normotensive counterparts (32.33 ± 5.56) years and (32.33 ± 5.56) kg/m2,respectively, were not statistically significant (P > 0.05). Serum matrix metalloprotease-2 (MMP-2) activity was significantly reduced in preeclampsia group (16.34 ± 7.07) compared with the normotensives (25.63 ± 4.56) (P < 0.001), and rs424243T/G variant (55.6%) was overrepresented among the cases compared with the normotensives (16.7%). The single-nucleotide polymorphism T/G was found to be associated with preeclampsia (odds ratio [OR] = 7.63; 95% confidence interval [CI] = 3.95-14.75; P < 0.0001). Decreased activity of MMP-2 and rs424243T/G SNP of EMMPRIN gene was reported in preeclampsia. These preliminary data warrant a further investigation into the relationship between EMMPRIN gene polymorphism and MMP-2 activity in preeclampsia.

Silencing of CD147 inhibits cell proliferation, migration, invasion, lipid metabolism dysregulation and promotes apoptosis in lung adenocarcinoma via blocking the Rap1 signaling pathway.

OBJECTIVE: CD147 is an important glycoprotein that participates in the progression of diverse cancers. This study aims to explore the specific function of CD147 in lung adenocarcinoma (LUAD) and to reveal related downstream molecular mechanisms. METHODS: Followed by silencing of CD147, the viability, migration, invasion, and apoptosis of LUAD cells were measured by CCK8, wound healing, transwell assay, and flow cytometer, respectively. The expression of CD147 and two markers of lipid metabolism (FASN and ACOX1) were detected by qRT-PCR. A xenograft tumor model was constructed to investigate the function of CD147 in vivo. Then transcriptome sequencing was performed to explore the potential mechanisms. After measuring the expression of Rap1 and p-p38 MAPK/p38 MAPK by western blot, the changes of CD147 and lipid metabolism markers (FASN, ACOX1) was detected by Immunohistochemistry. Moreover, a Rap1 activator and a Rap1 inhibitor were applied for feedback functional experiments. RESULTS: CD147 was up-regulated in LUAD cells, and its silencing inhibited cell proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis, while overexpression of CD147 showed the opposite results. Silencing of CD147 also inhibited the growth of tumor xenografts in mice. Transcriptome sequencing revealed 834 up-regulated differentially expressed genes (DEGs) and 602 down-regulated DEGs. After functional enrichment, the Rap1 signaling pathway was selected as a potential target, which was then verified to be blocked by CD147 silencing. In addition, the treatment of Rap1 activator weakened the inhibiting effects of si-CD147 on the proliferation, migration, invasion, and lipid metabolism in LUAD cells, while the intervention of RAP1 inhibitor showed the opposite results. CONCLUSIONS: Silencing of CD147 inhibited the proliferation, migration, invasion, lipid metabolism dysregulation and promoted apoptosis of LUAD cells through blocking the Rap1 signaling pathway.

Cluster of differentiation 147 (CD147) as potential membrane protein biomarker for bladder cancer cells.

Studies reveal that alterations in membrane protein (MP) patterns are associated with underlying drug resistance to chemotherapy. Therefore, the tryptic-digested MPs from the bladder cancer cell line were subjected to global proteomics using LC-MS/MS to identify the highly expressed potential MPs in bladder cancer cells. Our findings revealed the identification of MP biomarkers, CD147, and caveolin-1. Immunocytochemistry analysis confirmed the presence of CD147 on the cell membrane, while caveolin-1 showed positive signals without apparent staining on the membrane, suggesting its existence in multiple locations. Western blot analysis confirmed the higher expression of CD147 in non-invasive (RT 112) and metastatic (UM-UC-13) bladder cancer cells compared to invasive bladder cancer cells (5637 and J82), suggesting its potential as an MP biomarker for both of the former subtypes. The identified MPs could be used as drug therapy targets aimed at improving drug sensitivity and enhancing treatment outcomes in bladder cancer patients. SIGNIFICANCE: Identification of the membrane proteins associated with bladder cancer recurrence is crucial to understanding the mechanisms underlying the drug resistance to chemotherapy.

Erythrocyte invasion-neutralising antibodies prevent Plasmodium falciparum RH5 from binding to basigin-containing membrane protein complexes.

Basigin is an essential host receptor for invasion of Plasmodium falciparum into human erythrocytes, interacting with parasite surface protein PfRH5. PfRH5 is a leading blood-stage malaria vaccine candidate and a target of growth-inhibitory antibodies. Here, we show that erythrocyte basigin is exclusively found in one of two macromolecular complexes, bound either to plasma membrane Ca2+-ATPase 1/4 (PMCA1/4) or to monocarboxylate transporter 1 (MCT1). PfRH5 binds to each of these complexes with a higher affinity than to isolated basigin ectodomain, making it likely that these are the physiological targets of PfRH5. PMCA-mediated Ca2+ export is not affected by PfRH5, making it unlikely that this is the mechanism underlying changes in calcium flux at the interface between an erythrocyte and the invading parasite. However, our studies rationalise the function of the most effective growth-inhibitory antibodies targeting PfRH5. While these antibodies do not reduce the binding of PfRH5 to monomeric basigin, they do reduce its binding to basigin-PMCA and basigin-MCT complexes. This indicates that the most effective PfRH5-targeting antibodies inhibit growth by sterically blocking the essential interaction of PfRH5 with basigin in its physiological context.