Wogonin alleviates liver injury in sepsis through Nrf2-mediated NF-κB signalling suppression.

Sepsis is a life-threatening organ dysfunction syndrome, and liver is a susceptible target organ in sepsis, because the activation of inflammatory pathways contributes to septic liver injury. Oxidative stress has been documented to participate in septic liver injury, because it not only directly induces oxidative genotoxicity, but also exacerbates inflammatory pathways to potentiate damage of liver. Therefore, to ameliorate oxidative stress is promising for protecting liver in sepsis. Wogonin is the compound extracted from the medicinal plant Scutellaria baicalensis Geogi and was found to exert therapeutic effects in multiple inflammatory diseases via alleviation of oxidative stress. However, whether wogonin is able to mitigate septic liver injury remains unknown. Herein, we firstly proved that wogonin treatment could improve survival of mice with lipopolysaccharide (LPS)- or caecal ligation and puncture (CLP)-induced sepsis, together with restoration of reduced body temperature and respiratory rate, and suppression of several pro-inflammatory cytokines in circulation. Then, we found that wogonin effectively alleviated liver injury via potentiation of the anti-oxidative capacity. To be specific, wogonin activated Nrf2 thereby promoting expressions of anti-oxidative enzymes including NQO-1, GST, HO-1, SOD1 and SOD2 in hepatocytes. Moreover, wogonin-induced Nrf2 activation could suppress NF-κB-regulated up-regulation of pro-inflammatory cytokines. Ultimately, we provided in vivo evidence that wogonin activated Nrf2 signalling, potentiated anti-oxidative enzymes and inhibited NF-κB-regulated pro-inflammatory signalling. Taken together, this study demonstrates that wogonin can be the potential therapeutic agent for alleviating liver injury in sepsis by simultaneously ameliorating oxidative stress and inflammatory response through the activation of Nrf2.

F-Box Protein FBXO22 Mediates Polyubiquitination and Degradation of CD147 to Reverse Cisplatin Resistance of Tumor Cells.

Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD) prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells.

Dominant Suppression of ß1 Integrin by Ectopic CD98-ICD Inhibits Hepatocellular Carcinoma Progression.

Hepatocellular carcinoma (HCC) is currently the third most common cause of cancer-related death in the Asia-Pacific region. Our previous work showed that knockdown of CD98 significantly inhibits malignant HCC cell phenotypes in vitro and in vivo. The level of CD98 in the membrane is tightly regulated to mediate complex processes associated with cell-cell communication and intracellular signaling. In addition, the intracellular domain of CD98 (CD98-ICD) seems to be of vital importance for recycling CD98 to the membrane after it is endocytosed. The intracellular and transmembrane domains of CD98 associate with ß-integrins (primarily ß1 but also ß3), and this association is essential for CD98 mediation of integrin-like signaling and complements dominant suppression of ß1-integrin. We speculated that isolated CD98-ICD would similarly suppress ß1-integrin activation and inhibit the malignant behaviors of cancer cells. In particular, the exact role of CD98-ICD has not been studied independently in HCC. In this study, we found that ectopic expression of CD98-ICD inhibited the malignant phenotypes of HCC cells, and the mechanism possibly involves ß1-integrin suppression. Moreover, the expression levels of CD98, ß1-integrin-A (the activated form of ß1-integrin) and Ki-67 were significantly increased in HCC tissues relative to those of normal liver tissues. Therefore, our preliminary study indicates that ectopic CD98-ICD has an inhibitory role in the malignant development of HCC, and shows that CD98-ICD acts as a dominant negative mutant of CD98 that attenuates ß1-integrin activation. CD98-ICD may emerge as a promising candidate for antitumor treatment.

Full-length soluble CD147 promotes MMP-2 expression and is a potential serological marker in detection of hepatocellular carcinoma.

BACKGROUND: As a surface glycoprotein, CD147 is capable of stimulating the production of matrix metalloproteinases (MMPs) from neighboring fibroblasts. The aim of the present study is to explore the role of soluble CD147 on MMPs secretion from hepatocellular carcinoma (HCC) cells, and to investigate the diagnostic value of serum soluble CD147 in the HCC detection. METHODS: We identified the form of soluble CD147 in cell culture supernate of HCC cells and serum of patients with HCC, and explored the role of soluble CD147 on MMPs secretion. Serum CD147 levels were detected by the enzyme-linked immunosorbent assay, and the value of soluble CD147 as a marker in HCC detection was analyzed. RESULTS: Full length soluble CD147 was presented in the culture medium of HCC cells and serum of patients with HCC. The extracellular domain of soluble CD147 promoted the expression of CD147 and MMP-2 from HCC cells. Knockdown of CD147 markedly diminished the up-regulation of CD147 and MMP-2 which induced by soluble CD147. Soluble CD147 activated ERK, FAK, and PI3K/Akt pathways, leading to the up-regulation of MMP-2. The level of soluble CD147 in serum of patients with HCC was significantly elevated compared with healthy individuals (P < 0.001). Soluble CD147 levels were found to be associated with HCC tumor size (P = 0.007) and Child-Pugh grade (P = 0.007). Moreover, soluble CD147 showed a better performance in distinguishing HCC compared with alpha-fetoprotein. CONCLUSIONS: The extracellular domain of soluble CD147 enhances the secretion of MMP-2 from HCC cells, requiring the cooperation of membrane CD147 and activation of ERK, FAK, and PI3K/Akt signaling. The measurement of soluble CD147 may offer a useful approach in diagnosis of HCC.

[Effect of premature birth on retinal vascular development in the neonatal rat].

OBJECTIVE: To study the effects of premature birth on the development of rat retinal vasculature. METHODS: Experimental study. Sixty pregnant Sprague-Dawley rats were divided into four groups: bacterial lipopolysaccharide-induced preterm group (LPS group), RU-486 induced preterm group (RP group), cesarean section induced preterm group (CP group), and the normal delivery rats as the control group. The weight of rats from each group was recorded until postnatal day 21. On postnatal day 4, 7, 10 and 14 (P4, P7, P10 and P14), the retina of right eye was dissected and whole-mounted. Each premature group was divided into two subgroups based on the number of rats in each litter, the small subgroup (6-8 rats per litter, group 1) and the large subgroup (14-18 rats per litter, group 2). The development of retinal vascularization process was observed on P4, P7 and P10 (n = 6).Independent t test, one-way ANOVA and LSD-t test were used to analyzed the results. RESULTS: The weight of premature rats in LPS, CP and RP groups was significantly lower than that in the normal group within postnatal 21 days (LSD-t test: all P < 0.05). On the P4 and P7 in LPS group, the proportions of retinal superficial vascularized area of newborn rats [(0.47 ± 0.02) % ,(0.63 ± 0.04)%] were less than that in the normal group [(0.57 ± 0.04) % , (0.74 ± 0.05)%] (t4 d = 6.427, P 4 d = 0.000;t7 d = 5.111, P 7 d = 0.000). On the P4 and P7 in RP group, this proportions [(0.49 ± 0.04) %,(0.65 ± 0.04)%] were less than that in the normal group [(0.57 ± 0.04) %, (0.74 ± 0.05)%] (t4 d = 4.469, P 4 d = 0.000;t7 d = 2.491, P 7 d = 0.022). On P4, P7 and P10 in CP group, this proportions [(0.49 ± 0.05) %, (0.61 ± 0.05) %, (0.94 ± 0.03)%] were also less than that in the normal group[ (0.57 ± 0.04) %, (0.74 ± 0.05) %, (0.97 ± 0.02)%] (t4 d = 4.044, P 4 d = 0.001;t7 d = 6.011, P 7 d = 0.000; t 10 d = 2.331, P 10 d = 0.030). Retinal superficial vascularization completed on P14 in all groups. On the P4 and P7 in LPS group, the proportion of retinal vascularized area of group 2 [(0.44 ± 0.02)%, (0.60 ± 0.03)%] were less than that of group 1 [(0.53 ± 0.04)%, (0.74 ± 0.03)%] (t4 d = 3.852, P 4 d = 0.008; t7 d = 5.630, P 7 d = 0.001). On the P4 and P7 in CP group, this proportion in group 2 [(0.43 ± 0.02)%, (0.64 ± 0.03)%] were less than that of group 1 [ (0.54 ± 0.03)%, (0.76 ± 0.02)%] (t4 d = 4.695, P 4 d = 0.003; t7 d = 6.025, P 7 d = 0.001). On P4 in RP group, the proportions of group 2 [ (0.44 ± 0.01)%] was less than that of group 1 [ (0.54 ± 0.04)%] (t4 d = 5.000, P 4 d = 0.002). CONCLUSIONS: The premature rats have lower weight and much slower rate of early retinal vascularization, as compared with the normal rats. Furthermore, in the premature rats, the proportion of retinal vascularization in larger litters is less than that in smaller litters. These results indicate that premature birth and larger litter size have effects on the development of rat retinal vasculature.

Monoclonal antibody targeting mu-opioid receptor attenuates morphine tolerance via enhancing morphine-induced receptor endocytosis.

Morphine is a frequently used analgesic that activates the mu-opioid receptor (MOR), which has prominent side effects of tolerance. Although the inefficiency of morphine in inducing the endocytosis of MOR underlies the development of morphine tolerance, currently, there is no effective therapy to treat morphine tolerance. In the current study, we aimed to develop a monoclonal antibody (mAb) precisely targeting MOR and to determine its therapeutic efficacy on morphine tolerance and the underlying molecular mechanisms. We successfully prepared a mAb targeting MOR, named 3A5C7, by hybridoma technique using a strategy of deoxyribonucleic acid immunization combined with cell immunization, and identified it as an immunoglobulin G mAb with high specificity and affinity for MOR and binding ability to antigens with spatial conformation. Treatment of two cell lines, HEK293T and SH-SY5Y, with 3A5C7 enhanced morphine-induced MOR endocytosis via a G protein-coupled receptor kinase 2 (GRK2)/ß-arrestin2-dependent mechanism, as demonstrated by immunofluorescence staining, flow cytometry, Western blotting, coimmunoprecipitation, and small interfering ribonucleic acid (siRNA)-based knockdown. This mAb also allowed MOR recycling from cytoplasm to plasma membrane and attenuated morphine-induced phosphorylation of MOR. We established an in vitro morphine tolerance model using differentiated SH-SY5Y cells induced by retinoic acid. Western blot, enzyme-linked immunosorbent assays, and siRNA-based knockdown revealed that 3A5C7 mAb diminished hyperactivation of adenylate cyclase, the in vitro biomarker of morphine tolerance, via the GRK2/ß-arrestin2 pathway. Furthermore, in vivo hotplate test demonstrated that chronic intrathecal administration of 3A5C7 significantly alleviated morphine tolerance in mice, and withdrawal jumping test revealed that both chronic and acute 3A5C7 intrathecal administration attenuated morphine dependence. Finally, intrathecal electroporation of silencing short hairpin RNA illustrated that the in vivo anti-tolerance and anti-dependence efficacy of 3A5C7 was mediated by enhanced morphine-induced MOR endocytosis via GRK2/ß-arrestin2 pathway. Collectively, our study provided a therapeutic mAb, 3A5C7, targeting MOR to treat morphine tolerance, mediated by enhancing morphine-induced MOR endocytosis. The mAb 3A5C7 demonstrates promising translational value to treat clinical morphine tolerance.

Cysteine carboxyethylation generates neoantigens to induce HLA-restricted autoimmunity.

Autoimmune diseases such as ankylosing spondylitis (AS) can be driven by emerging neoantigens that disrupt immune tolerance. Here, we developed a workflow to profile posttranslational modifications involved in neoantigen formation. Using mass spectrometry, we identified a panel of cysteine residues differentially modified by carboxyethylation that required 3-hydroxypropionic acid to generate neoantigens in patients with AS. The lysosomal degradation of integrin αIIb [ITGA2B (CD41)] carboxyethylated at Cys96 (ITGA2B-ceC96) generated carboxyethylated peptides that were presented by HLA-DRB1*04 to stimulate CD4+ T cell responses and induce autoantibody production. Immunization of HLA-DR4 transgenic mice with the ITGA2B-ceC96 peptide promoted colitis and vertebral bone erosion. Thus, metabolite-induced cysteine carboxyethylation can give rise to pathogenic neoantigens that lead to autoreactive CD4+ T cell responses and autoantibody production in autoimmune diseases.

Mechanism of opioid addiction and its intervention therapy: Focusing on the reward circuitry and mu-opioid receptor.

Opioid abuse and addiction have become a global pandemic, posing tremendous health and social burdens. The rewarding effects and the occurrence of withdrawal symptoms are the two mainstays of opioid addiction. Mu-opioid receptors (MORs), a member of opioid receptors, play important roles in opioid addiction, mediating both the rewarding effects of opioids and opioid withdrawal syndrome (OWS). The underlying mechanism of MOR-mediated opioid rewarding effects and withdrawal syndrome is of vital importance to understand the nature of opioid addiction and also provides theoretical basis for targeting MORs to treat drug addiction. In this review, we first briefly introduce the basic concepts of MORs, including their structure, distribution in the nervous system, endogenous ligands, and functional characteristics. We focused on the brain circuitry and molecular mechanism of MORs-mediated opioid reward and withdrawal. The neuroanatomical and functional elements of the neural circuitry of the reward system underlying opioid addiction were thoroughly discussed, and the roles of MOR within the reward circuitry were also elaborated. Furthermore, we interrogated the roles of MORs in OWS, along with the structural basis and molecular adaptions of MORs-mediated withdrawal syndrome. Finally, current treatment strategies for opioid addiction targeting MORs were also presented.

Blockade of mIL-6R alleviated lipopolysaccharide-induced systemic inflammatory response syndrome by suppressing NF-κB-mediated Ccl2 expression and inflammasome activation.

Systemic inflammatory response syndrome (SIRS) is characterized by dysregulated cytokine release, immune responses and is associated with organ dysfunction. IL-6R blockade indicates promising therapeutic effects in cytokine release storm but still remains unknown in SIRS. To address the issue, we generated the human il-6r knock-in mice and a defined epitope murine anti-human membrane-bound IL-6R (mIL-6R) mAb named h-mIL-6R mAb. We found that the h-mIL-6R and the commercial IL-6R mAb Tocilizumab significantly improved the survival rate, reduced the levels of TNF-α, IL-6, IL-1ß, IFN-γ, transaminases and blood urea nitrogen of LPS-induced SIRS mice. Besides, the h-mIL-6R mAb could also dramatically reduce the levels of inflammatory cytokines in LPS-treated THP-1 cells in vitro. RNA-seq analysis indicated that the h-mIL-6R mAb could regulate LPS-induced activation of NF-κB/Ccl2 and NOD-like receptor signaling pathways. Furthermore, we found that the h-mIL-6R mAb could forwardly inhibit Ccl2 expression and NLRP3-mediated pyroptosis by suppressing NF-κB in combination with the NF-κB inhibitor. Collectively, mIL-6R mAbs suppressed NF-κB/Ccl2 signaling and inflammasome activation. IL-6R mAbs are potential alternative therapeutics for suppressing excessive cytokine release, over-activated inflammatory responses and alleviating organ injuries in SIRS.

Inhibition of mu-opioid receptor suppresses proliferation of hepatocellular carcinoma cells via CD147-p53-MAPK cascade signaling pathway.

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths. Previous studies have suggested that mu-opioid receptor (MOR), a member of the opioid receptor family, is involved in the pathogenesis of HCC. However, the mechanism by which MOR regulates the biological behavior of HCC is still poorly understood. To address this problem, in this study, we investigated the role of MOR in the proliferation of HCC cell lines and the underlying mechanism. First, RT-PCR, western-blot and immunohistochemistry revealed higher expression of MOR in HCC cells and tissue than in non-tumor cells or adjacent tissue, and elevated expression of MOR was associated with jeopardized survival of HCC patients, as demonstrated by bioinformatic databases. Knockdown of MOR by specific siRNA attenuated the proliferation and migration of HCC cells and this effect could be reversed by rescue experiments, confirming the essential role of MOR in the proliferation of HCC. Moreover, results of colony formation assay, CCK8 test, flow cytometry and western blot suggested that a monoclonal antibody (mAb) specifically against MOR could inhibit proliferation of HepG2 and Huh7 cells via the MOR-CD147-p53-MAPK pathway, and the interaction between MOR and CD147 was verified by immunofluorescence colocalization and co-IP analysis. The mAb against MOR also enhanced the cisplatin-induced apoptosis of HCC cells by downregulating p-ERK, Bcl-2 and upregulating Bax. Taken together, these results suggest that MOR could regulate the proliferation of HCC cells in a CD147-p53-MAPK dependent manner. MOR possesses the potential to be a therapeutic target to treat HCC.

Prognostic Landscape of Tumor-Infiltrating T and B Cells in Human Cancer.

Recently, immunotherapy targeting tumor-infiltrating lymphocytes (TILs) has emerged as a critical and promising treatment in several types of cancer. However, not all cancer types have been tested in immunotherapeutic trials, and different patients and cancer types may have unpredictable clinical outcomes. This situation has created a particular exigency for analyzing the prognostic significance of tumor-infiltrating T cells (TIL-T) and B cells (TIL-B) across different cancer types. To address the critical role of TILs, the abundances of TIL-T and TIL-B cells, as determined by the protein levels of LCK and CD20, were analyzed across heterogeneous human malignancies. TIL-T and TIL-B cells showed varying prognostic significances across heterogeneous cancer types. Additionally, distinct distributions of TIL-T and TIL-B cells were observed in different cancer and tumor microenvironment (TME) subtypes. Next, we analyzed the cellular context for the TME communication network involving the well-acknowledgeable chemokine receptors of TIL-T and TIL-B cells, implying the functional interactions with TME. Additionally, these chemokine receptors, expressed by TIL-T and TIL-B cells, were remarkably correlated with the levels of TIL-T or TIL-B cell infiltrations across nearly all the cancer types, indicating these chemokine receptors as universal targets for up- and down-regulating the TIL-T and TIL-B cells. Lastly, we provide the prognostic landscape of TIL-T and TIL-B cells across 30 cancer types and the subgroups defined by gender, histopathology, histological grade, therapeutic approach, drug, and TME subtype, which are intended to be a resource to fuel the investigations of TILs, with important implications for cancer immunotherapy.

CD147 receptor is essential for TFF3-mediated signaling regulating colorectal cancer progression.

Major gaps in understanding the molecular mechanisms of colorectal cancer (CRC) progression and intestinal mucosal repair have hampered therapeutic development for gastrointestinal disorders. Trefoil factor 3 (TFF3) has been reported to be involved in CRC progression and intestinal mucosal repair; however, how TFF3 drives tumors to become more aggressive or metastatic and how TFF3 promotes intestinal mucosal repair are still poorly understood. Here, we found that the upregulated TFF3 in CRC predicted a worse overall survival rate. TFF3 deficiency impaired mucosal restitution and adenocarcinogenesis. CD147, a membrane protein, was identified as a binding partner for TFF3. Via binding to CD147, TFF3 enhanced CD147-CD44s interaction, resulting in signal transducer and activator of transcription 3 (STAT3) activation and prostaglandin G/H synthase 2 (PTGS2) expression, which were indispensable for TFF3-induced migration, proliferation, and invasion. PTGS2-derived PGE2 bound to prostaglandin E2 receptor EP4 subtype (PTGER4) and contributed to TFF3-stimulated CRC progression. Solution NMR studies of the TFF3-CD147 interaction revealed the key residues critical for TFF3 binding and the induction of PTGS2 expression. The ability of TFF3 to enhance mucosal restitution was weakened by a PTGS2 inhibitor. Blockade of TFF3-CD147 signaling using competitive inhibitory antibodies or a PTGS2 inhibitor reduced CRC lung metastasis in mice. Our findings bring strong evidence that CD147 is a novel receptor for TFF3 and PTGS2 signaling is critical for TFF3-induced mucosal restitution and CRC progression, which widens and deepens the understanding of the molecular function of trefoil factors.

Safety and efficacy of meplazumab in healthy volunteers and COVID-19 patients: a randomized phase 1 and an exploratory phase 2 trial.

Recent evidence suggests that CD147 serves as a novel receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Blocking CD147 via anti-CD147 antibody could suppress the in vitro SARS-CoV-2 replication. Meplazumab is a humanized anti-CD147 IgG2 monoclonal antibody, which may effectively prevent SARS-CoV-2 infection in coronavirus disease 2019 (COVID-19) patients. Here, we conducted a randomized, double-blinded, placebo-controlled phase 1 trial to evaluate the safety, tolerability, and pharmacokinetics of meplazumab in healthy subjects, and an open-labeled, concurrent controlled add-on exploratory phase 2 study to determine the efficacy in COVID-19 patients. In phase 1 study, 59 subjects were enrolled and assigned to eight cohorts, and no serious treatment-emergent adverse event (TEAE) or TEAE grade ≥3 was observed. The serum and peripheral blood Cmax and area under the curve showed non-linear pharmacokinetic characteristics. No obvious relation between the incidence or titer of positive anti-drug antibody and dosage was observed in each cohort. The biodistribution study indicated that meplazumab reached lung tissue and maintained >14 days stable with the lung tissue/cardiac blood-pool ratio ranging from 0.41 to 0.32. In the exploratory phase 2 study, 17 COVID-19 patients were enrolled, and 11 hospitalized patients were involved as concurrent control. The meplazumab treatment significantly improved the discharged (P = 0.005) and case severity (P = 0.021), and reduced the time to virus negative (P = 0.045) in comparison to the control group. These results show a sound safety and tolerance of meplazumab in healthy volunteers and suggest that meplazumab could accelerate the recovery of patients from COVID-19 pneumonia with a favorable safety profile.

CD147-spike protein is a novel route for SARS-CoV-2 infection to host cells.

In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2, no specific and effective drugs for treating this disease have been reported until today. Angiotensin-converting enzyme 2 (ACE2), a receptor of SARS-CoV-2, mediates the virus infection by binding to spike protein. Although ACE2 is expressed in the lung, kidney, and intestine, its expressing levels are rather low, especially in the lung. Considering the great infectivity of COVID-19, we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection. Here, we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein. The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody, Meplazumab, inhibits SARS-CoV-2 amplification. Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells, which can be neutralized by CD147 extracellular fragment. Viral loads are detectable in the lungs of human CD147 (hCD147) mice infected with SARS-CoV-2, but not in those of virus-infected wild type mice. Interestingly, virions are observed in lymphocytes of lung tissue from a COVID-19 patient. Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dose-dependent manner, which is specifically inhibited by Meplazumab. Furthermore, CD147 mediates virus entering host cells by endocytosis. Together, our study reveals a novel virus entry route, CD147-spike protein, which provides an important target for developing specific and effective drug against COVID-19.

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

AIMS: To evaluate HAb18G/CD147 as a cancer-associated biomarker using its monoclonal antibody HAb18. METHODS AND RESULTS: On immunohistochemical analysis of 28 tissue microarrays and pathological sections of 1117 breast tissue samples, HAb18G/CD147 was expressed in carcinoma with an overall positivity rate of 67.76%, which was significantly higher than that in sarcomas (27.34%, P < 0.0001) and normal epithelial (5.18%, P < 0.0001) and fetal (2.67%, P < 0.0001) tissues. In epithelial tissues from 14 organs, the difference in HAb18G/CD147 expression between normal epithelium and the corresponding carcinoma was also significant (P < 0.05 for each pair). This expression in carcinoma was also found at the mRNA level, suggesting transcriptional level regulation of HAb18G/CD147 expression. In a retrospective study of 106 patients with infiltrating ductal carcinoma of the breast, the level of HAb18G/CD147 expression was positively correlated with tumour recurrence/metastasis (P = 0.0003) and negatively correlated with survival of breast cancer patients (P = 0.002). Multivariable Cox regression analysis showed that HAb18G/CD147 was an independent prognostic factor. CONCLUSIONS: HAb18G/CD147 is significantly expressed in various cancers and appears to have prognostic significance, rendering it a possible cancer-associated biomarker for pathological diagnosis, prognostic evaluation, targeted therapy and radioimmunoimaging of a broad range of cancer types.

HAb18G/CD147 functions in invasion and metastasis of hepatocellular carcinoma.

CD147 molecule is reported to be correlated with the malignancy of some cancers; however, it remains unclear whether it is involved in the progression of hepatocellular carcinoma (HCC). Here, we investigated the function of HAb18G/CD147, a member of CD147 family, and its antibodies, HAb18 and LICARTIN, in HCC invasion and metastasis. We observed that HAb18G/CD147 gene silence in HCC cells significantly decreased the secretion of matrix metalloproteinase (MMP) and the invasive potential of HCC cells (P < 0.001). MMP silence in HCC cells also significantly suppressed the invasion of the cells when cocultured with fibroblasts; however, its inhibitory effect was significantly weaker than that of both HAb18G/CD147 silence in HCC cells and that of MMP silence in fibroblasts (P < 0.001). Blocking theHAb18G/CD147 molecule on HCC cells with HAb18 monoclonal antibody resulted in a similar suppressive effect on MMP secretion and cell invasion, but with no significant effects on the cell growth. (131)I-labeled HAb18 F(ab')(2) (LICARTIN), however, significantly inhibited the in vitro growth of HCC cells (P < 0.001). In an orthotopic model of HCC in nude mice, HAb18 and LICARTIN treatment effectively reduced the tumor growth and metastasis as well as the expression of three major factors in the HCC microenviroment (MMPs, vascular endothelial growth factor, and fibroblast surface protein) in the paracancer tissues. Overall, these results suggest that HAb18G/CD147 plays an important role in HCC invasion and metastasis mainly via modulating fibroblasts, as well as HCC cells themselves to disrupt the HCC microenviroment. LICARTIN can be used as a drug targeting to HAb18G/CD147 in antimetastasis and recurrence therapy of HCC.

BetaIg-h3 is involved in the HAb18G/CD147-mediated metastasis process in human hepatoma cells.

HAb18G/CD147, a new hepatoma-associated antigen cloned and screened from human hepatocellular carcinoma cDNA library, is closely correlated with metastasis process in human hepatoma cells. In the present study we aimed to identify the pivotal molecules of the HAb18G/CD147 signal transduction pathway. The investigation showed that betaig-h3, a secretory extracellular matrix (ECM) protein, was upregulated in HAb18G/CD147-expressing human hepatoma T7721 cells and was downregulated by depressing HAb18G/CD147 expression. The expression of betaig-h3, upregulated in human hepatoma cells, was positively relative to the expression of HAb18G/CD147 in different human hepatoma cell lines. By overexpressing betaig-h3 in human SMMC-7721 hepatoma cells, we discovered that betaig-h3 promoted cell adhesion, invasion, and matrix metalloproteinase (MMP) secretion potential. HAb18G/CD147-induced invasion and metastasis potential of human hepatoma cells can be attenuated by antibodies specific for betaig-h3, and no significant differences on inhibitory effects were observed among T7721 cells incubated with antibodies for betaig-h3 or HAb18G/CD147 or both types together. Taken together, our study suggests that betaig-h3, regulated by the expression of HAb18G/CD147, is involved in the HAb18G/CD147 signal transduction pathway and mediates the HAb18G/CD147-induced invasion and metastasis process of human hepatoma cells.

Cytoplasmic fragment of CD147 generated by regulated intramembrane proteolysis contributes to HCC by promoting autophagy.

Hepatocellular carcinoma (HCC) is one of the most lethal and prevalent cancers worldwide. CD147 (EMMPRIN or basigin) is a leading gene relating to hepatocarcinogenesis and metastasis, and is detected in transmembrane, exosome or circulating forms in HCC patients. The endosome recycling of CD147 further enhances the function of this oncoprotein from a dynamic perspective. However, previous studies about CD147 mainly focused on one separate form, and little attention has been paid to how the different forms of tumor-derived CD147 changes. Moreover, uncovering the roles of the residual C-terminal portion of CD147 after shedding is inevitable to fully understand CD147 promoting tumor progression. In this study, we discovered that under low-cholesterol condition, CD147 endocytosis is inhibited but its shedding mediated by ADAM10 is enhanced. Further procession of residual CD147 in the lysosome produces nuclear-localized CD147-ICD (intracellular domain of CD147), which contributes to autophagy through NF-κB-TRAIL-caspase8-ATG3 axis. As autophagy endows cancer cells with increased adaptability to chemotherapy, and HAb 18 (a specific antibody targeting CD147) inhibits CD147 shedding and sequential CD147-ICD enhances autophagy, we found the combination of HAb 18 and cisplatin exhibited marked antitumor efficiency.

Targeting CD147 for T to NK Lineage Reprogramming and Tumor Therapy.

CD147 is highly expressed on the surface of numerous tumor cells to promote invasion and metastasis. Targeting these cells with CD147-specific antibodies has been validated as an effective approach for lung and liver cancer therapy. In the immune system, CD147 is recognized as a co-stimulatory receptor and impacts the outcome of thymic selection. Using T cell-specific deletion, we showed here that in thymus CD147 is indispensable for the stable αß T cell lineage commitment: loss of CD147 biases both multipotent DN (double negative) and fully committed DP (double positive) cells into innate NK-like lineages. Mechanistically, CD147 deficiency results in impaired Wnt signaling and expression of BCL11b, a master transcription factor in determining T cell identity. In addition, functional blocking of CD147 by antibody phenocopies genetic deletion to enrich NK-like cells in the periphery. Furthermore, using a melanoma model and orthotopic liver cancer transplants, we showed that the augmentation of NK-like cells strongly associates with resistance against tumor growth upon CD147 suppression. Therefore, besides its original function in tumorigenesis, CD147 is also an effective surface target for immune modulation in tumor therapy.

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

PURPOSE: HAb18G/CD147 is a hepatocellular carcinoma (HCC)-associated antigen. We developed iodine (131I) metuximab injection (Licartin), a novel 131I-labeled HAb18G/CD147-specific monoclonal antibody Fab'2 fragment, and evaluated its safety, pharmacokinetics, and clinical efficacy on HCC in Phase I/II trials. METHODS AND MATERIALS: In a Phase I trial, 28 patients were randomly assigned to receive the injection in 9.25-, 18.5-, 27.75-, or 37-MBq/kg doses by hepatic artery infusion. In a multicenter Phase II trial, 106 patients received the injection (27.75 MBq/kg) on Day 1 of a 28-day cycle. Response rate and survival rate were the endpoints. RESULTS: No life-threatening toxic effects were found. The safe dosage was 27.75 MBq/kg. The blood clearance fitted a biphasic model, and its half-life was 90.56-63.93 h. In the Phase II trial, the injection was found to be targeted and concentrated to tumor tissues. Of the 73 patients completing two cycles, 6 (8.22%) had a partial response, 14 (19.18%) minor response, and 43 (58.90%) stable disease. The 21-month survival rate was 44.54%. The survival rate of progression-free patients was significantly higher than that of patients with progressive disease after either one or two cycles (p < 0.0001 or p = 0.0019). CONCLUSION: Iodine (131I) metuximab injection is safe and active for HCC patients.