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

Shikonin reverses pyruvate kinase isoform M2-mediated propranolol resistance in infantile hemangioma through reactive oxygen species-induced autophagic dysfunction

Infantile hemangioma (IH) is the most common benign tumor in infancy. Propranolol, a nonselective β-adrenergic receptor blocker, is now the first-line therapy for IH. Recently, low sensitivity to propranolol therapy has become one major reason for the failure of IH treatment. However, the exact underlying mechanisms are yet to be fully elucidated. Here, we reported that pyruvate kinase isoform M2 (PKM2), an essential glycolytic enzyme, played a critical role in regulating the progression of IH and the therapeutic resistance of propranolol treatment. Shikonin reversed the propranolol resistance in hemangioma-derived endothelial cells and in hemangioma animal models. Moreover, shikonin combined with propranolol could induce excessive reactive oxygen species (ROS) accumulation and lead to autophagic dysfunction, which is essential for the enhanced therapeutic sensitivity of propranolol treatment. Taken together, our results indicated that PKM2 has a significant role in hemangiomas progression and therapeutic resistance; it could be a safe and effective therapeutic strategy for those hemangiomas with poor propranolol sensitivity combined with shikonin.

Bidirectional Relationship between COVID-19 and Diabetes: Role of Renin-Angiotensin-Aldosterone System and Drugs Modulating It

Numerous reports have suggested that diabetic patients are at high risk for the development of severe symptoms of coronavirus disease-2019 (COVID-19). However, a few studies have recently proposed that the relationship between diabetes and COVID-19 is bidirectional, as severe acute respiratory syndrome-coronavirus-2 also has the capability to induce diabetes. Various mechanisms have been identified and proposed to be involved in this binary association. In this review, the importance and impact of renin-angiotensin-aldosterone system (RAAS) in this two-way association of COVID-19 and diabetes has been summarized. The role and effect of drugs modulating RAAS directly or indirectly has also been discussed, as they can majorly impact the course of treatment in such patients. Further reports and data can present a clear picture of RAAS and its modulators in restoring the balance of dysregulated RAAS in COVID-19.

Beta-Adrenergic Blockers as a Potential Treatment for COVID-19 Patients

More than 15 million people have been affected by coronavirus disease 2019 (COVID-19) and it has caused 640 016 deaths as of July 26, 2020. Currently, no effective treatment option is available for COVID-19 patients. Though many drugs have been proposed, none of them has shown particular efficacy in clinical trials. In this article, the relationship between the Adrenergic system and the renin-angiotensin-aldosterone system (RAAS) is focused in COVID-19 and a vicious circle consisting of the Adrenergic system-RAAS-Angiotensin converting enzyme 2 (ACE2)-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (which is referred to as the "ARAS loop") is proposed. Hyperactivation of the ARAS loop may be the underlying pathophysiological mechanism in COVID-19, and beta-adrenergic blockers are proposed as a potential treatment option. Beta-adrenergic blockers may decrease the SARS-CoV-2 cellular entry by decreasing ACE2 receptors expression and cluster of differentiation 147 (CD147) in various cells in the body. Beta-adrenergic blockers may decrease the morbidity and mortality in COVID-19 patients by preventing or reducing acute respiratory distress syndrome (ARDS) and other complications. Retrospective and prospective clinical trials should be conducted to check the validity of the hypothesis. Also see the video abstract here https://youtu.be/uLoy7do5ROo.

Efficacy of TIMOLOL nasal spray as a treatment for epistaxis in hereditary hemorrhagic telangiectasia. A double-blind, randomized, placebo-controlled trial

Hereditary hemorrhagic telangiectasia is a rare vascular genetic disease. Epistaxis is the most frequent and disabling manifestation, and timolol appears to be a new therapeutic option as non-selective beta-blockers have in vitro and in vivo anti-angiogenic properties. Our main objective was to evaluate the efficacy of TIMOLOL nasal spray as a treatment for epistaxis in hereditary hemorrhagic telangiectasia. This study is a single-center, randomized, phase 2, double-blind placebo-controlled study with an allocation ratio of 1:1. It was proposed to patients with hereditary hemorrhagic telangiectasia monitored at the French Reference Center, and we included patients aged over 18 years, diagnosed with hereditary hemorrhagic telangiectasia and epistaxis. The treatment was self-administered by the patient with a posology of one spray (50 µL) of timolol 0.5% or placebo in each nostril twice a day for 28 consecutive days. The primary efficacy endpoint was mean monthly epistaxis duration, assessed by monitoring epistaxis grids. A total of 58 patients were randomized and treated. The baseline characteristics were similar in the 2 groups. Mean monthly epistaxis duration measured at 3 months was not significantly different in the 26 patients receiving the drug in comparison with the placebo group (p = 0.54). Toxicity was low and no severe adverse events were reported. One limitation is that we included all HHT patients with nosebleeds and did not take into account history of nasal surgery or nasal crusts. Timolol, administered by nasal spray at a dose of 0.25 mg in each nostril twice a day for 28 consecutive days, did not improve epistaxis in patients with hereditary hemorrhagic telangiectasia at 4 months after the beginning of the treatment.

Downregulation of CD147 induces malignant melanoma cell apoptosis via the regulation of IGFBP2 expression

Cluster of differentiation (CD)147, as a transmembrane glycoprotein, is highly expressed in a variety of tumors. Accumulating evidence has demonstrated that CD147 serves critical roles in tumor cell death and survival; however, the underlying mechanism requires further investigation. In the present study, it was revealed that CD147 knockdown significantly increased melanoma cell apoptosis. In addition, downregulation of CD147 reversed the malignant phenotype of melanoma, as demonstrated by the induction of tumor cell apoptosis in a xenograft mouse model. In addition, a human apoptosis antibody array was performed and 9 differentially expressed apoptosis-related proteins associated with CD147 were identified, including insulin-like growth factor-binding protein 2 (IGFBP2). Additionally, CD147 knockdown was observed to significantly decreased IGFBP2 expression at the mRNA and protein levels in melanoma cells. Providing that IGFBP2 is a downstream molecule in the phosphatase and tensin homolog (PTEN)/phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, the effects of CD147 on this particular pathway were investigated. Interestingly, the expression of phosphorylated (p)-AKT and p‑mechanistic target of rapamycin was attenuated, whereas PTEN was markedly upregulated in CD147-underexpressing melanoma cells. Furthermore, application of a PI3K‑specific inhibitor also decreased IGFBP2 expression. Importantly, IGFBP2 was highly expressed in clinical tissues of melanoma compared with the control group, and its expression exhibited a positive association with CD147. The present study revealed that CD147 served a critical role in mediating the apoptosis of melanoma cells via IGFBP2 and the PTEN/PI3K/AKT signaling pathway. IGFBP2 and CD147 were observed to be overexpressed in clinical melanoma tissues; IGFBP2 was shown to be positively associated with CD147 expression, suggesting that CD147 may be considered as a potential therapeutic target for chemotherapy or prevention for in melanoma.

Propranolol induced G0/G1/S phase arrest and apoptosis in melanoma cells via AKT/MAPK pathway

Both preclinical and epidemiology studies associate β-adrenoceptors-blockers (β-blockers) with activity against melanoma. However, the underlying mechanism is still unclear, especially in acral melanoma. In this study, we explored the effect of propranolol, a non-selective β-blocker, on the A375 melanoma cell line, two primary acral melanoma cell lines (P-3, P-6) and mice xenografts. Cell viability assay demonstrated that 50μM-400μM of propranolol inhibited viability in a concentration and time dependent manner with an IC50 ranging from 65.33μM to 148.60μM for 24h -72h treatment, but propranolol (less than 200μM) had no effect on HaCaT cell line. Western blots showed 100μM propranolol significantly reduced the expression of Bcl-2 while increasing the expressions of Bax, cytochrome c, cleaved capase-9 and cleaved caspase-3, and down-regulated the levels of p-AKT, p-BRAF, p-MEK1/2 and p-ERK1/2 in melanoma cells, after a 24h incubation. The in vivo data confirmed the isolation results. Mice received daily ip. administration of propranolol at the dose of 2 mg/kg for 3 weeks and the control group was treated with the same volume of saline. The mean tumor volume at day 21 in A375 xenografts was 82.33 ± 3.75mm3vs. 2044.67 ± 54.57mm3 for the propranolol-treated mice and the control group, respectively, and 31.66 ± 4.67 mm3vs. 1074.67 ± 32.17 mm3 for the P-3 xenografts. Propranolol also reduced Ki67, inhibited phosphorylation of AKT, BRAF, MEK1/2 and ERK1/2 in xenografts. These are the first data to demonstrate that propranolol might inhibit melanoma by activating the intrinsic apoptosis pathway and inactivating the MAPK and AKT pathways.

The fucosylated CD147 enhances the autophagy in epithelial ovarian cancer cells

Autophagy is modulated by multiple factors including CD147, but little is know about the effects and mechanism by which the modification of CD147 by Lewis y antigen regulates autophagy of ovarian cancer cell. Here, we reported that Lewis y antigen can promote basic autophagy activity and restrain autophagic cell death in ovarian cancer cells. Furthermore, human whole genome expression profile microarrays and massage pathway analysis revealed that during early stages of autophagy in ovarian cancer cells with highly expressing Lewis y antigen, PI3K/Akt-mTOR activity was reduced, in contrast, the PI3K/Akt-mTOR signaling pathway was activated as the length of amino acid deprivation increased, which inhibited eIF4G2 expression, further decreased the transcription of autophagy-related genes, suppressed autophagic cell death. we also elaborated that co-regulates protein degradation in cells via the ubiquitin-proteasome system and the autophagy-lysosome pathway. These findings suggested that the modification of CD147 by Lewis y antigen enhanced the survival ability by promoting basic autophagy activity and restraining autophagic cell death in ovarian cancer , thus playing an important role in ovarian cancer malignant progression.

CD147-targeted siRNA in A375 malignant melanoma cells induces the phosphorylation of EGFR and downregulates cdc25C and MEK phosphorylation

The Raf-MEK-ERK signaling pathway is important during oncogenesis. An activating mutation of BRAF constitutively activates the Raf-MEK-ERK signaling cascade, and has been identified in ~70% of malignant melanomas (MMs). Cluster of differentiation 147 (CD147)/basigin is an integral plasma membrane protein belonging to the immunoglobulin superfamily. The protein is highly expressed on MM cells, and promotes cellular proliferation and tumor growth. The present study investigated the correlation between CD147 expression and Raf-MEK-ERK signaling in MM using the A375 human MM cell line, which harbors the activating mutation of BRAF. The phosphorylation of epidermal growth factor receptor (EGFR) was upregulated, and mitogen-activated protein kinase kinase (MEK) and cell division cycle 25C phosphorylation was downregulated by CD147 silencing in the A375 cells. Cell growth was inhibited by the EGFR inhibitor erlotinib and by CD147 silencing, and additive growth inhibition was observed when these techniques were combined. The results of the present study indicate that the combination of EGFR and CD147 inhibition may be useful in BRAF-mutated MM.

Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) promotes lung fibroblast proliferation, survival and differentiation to myofibroblasts

Background

Idiopathic pulmonary fibrosis (IPF) is a chronic progressively fatal disease. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) is a glycosylated transmembrane protein that induces the expression of some matrix metalloproteinase (MMP) in neighboring stromal cells through direct epithelial–stromal interactions. EMMPRIN is highly expressed in type II alveolar epithelial cells at the edges of the fibrotic areas in IPF lung sections. However, the exact role of EMMPRIN in IPF is unknown.

Methods

To determine if EMMPRIN contributes to lung fibroblast proliferation, resistance to apoptosis, and differentiation to myofibroblasts, normal Human lung fibroblasts (NHLF) transiently transfected with either EMMPRIN/GFP or GFP were treated with TGF- β1 from 0 to 10 ng/ml for 48 h and examined for cell proliferation (thymidine incorporation), apoptosis (FACS analysis and Cell Death Detection ELISA assay), cell migration (Modified Boyden chamber) and differentiation to myofibroblasts using Western blot for α–smooth actin of cell lysates. The effect of EMMPRIN inhibition on NHLF proliferation, apoptosis, migration and differentiation to myofibroblasts after TGF- β1 treatment was examined using EMMPRIN blocking antibody. We examined the mechanism by which EMMPRIN induces its effects on fibroblasts by studying the β-catenin/canonical Wnt signaling pathway using Wnt luciferase reporter assays and Western blot for total and phosphorylated β-catenin.

Results

Human lung fibroblasts overexpressing EMMPRIN had a significant increase in cell proliferation and migration compared to control fibroblasts. Furthermore, EMMPRIN promoted lung fibroblasts resistance to apoptosis. Lung fibroblasts overexpressing EMMPRIN showed a significantly increased expression of α- smooth muscle actin, a marker of differentiation to myofibroblasts compared to control cells. TGF-β1 increased the expression of EMMPRIN in lung fibroblasts in a dose-dependent manner. Attenuation of EMMPRIN expression with the use of an EMMPRIN blocking antibody markedly inhibited TGF-β1 induced proliferation, migration, and differentiation of fibroblasts to myofibroblasts. EMMPRIN overexpression in lung fibroblasts was found to induce an increase in TOPFLASH luciferase reporter activity when compared with control fibroblasts.

Conclusion

These findings indicate that TGF-β1 induces the release of EMMPRIN that activates β-catenin/canonical Wnt signaling pathway. EMMPRIN overexpression induces an anti-apoptotic and pro-fibrotic phenotype in lung fibroblasts that may contribute to the persistent fibro-proliferative state seen in IPF.

Anti-angiogenic therapeutic strategies in hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular dysplastic disorder, characterized by recurrent nosebleeds (epistaxis), multiple telangiectases and arteriovenous malformations (AVMs) in major organs. Mutations in Endoglin (ENG or CD105) and Activin receptor-like kinase 1 (ACVRL1 or ALK1) genes of the TGF-β superfamily receptors are responsible for HHT1 and HHT2 respectively and account for the majority of HHT cases. Haploinsufficiency in ENG and ALK1 is recognized at the underlying cause of HHT. However, the mechanisms responsible for the predisposition to and generation of AVMs, the hallmark of this disease, are poorly understood. Recent data suggest that dysregulated angiogenesis contributes to the pathogenesis of HHT and that the vascular endothelial growth factor, VEGF, may be implicated in this disease, by modulating the angiogenic–angiostatic balance in the affected tissues. Hence, anti-angiogenic therapies that target the abnormal vessels and restore the angiogenic–angiostatic balance are candidates for treatment of HHT. Here we review the experimental evidence for dysregulated angiogenesis in HHT, the anti-angiogenic therapeutic strategies used in animal models and some patients with HHT and the potential benefit of the anti-angiogenic treatment for ameliorating this severe, progressive vascular disease.

Intracellular Acidosis Promotes Mitochondrial Apoptosis Pathway: Role of EMMPRIN Down-regulation via Specific Single-chain Fv Intrabody

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a human leukocyte surface molecule that is enriched on the surface of many cancer cells, and it plays an important role in proliferation and metastasis. In this study, we utilized the chimeric adenoviral vector Ad5/F35 carrying gene encoding scFv against EMMPRIN (scFv-M6-1B9) to down-regulate EMMPRIN cell surface expression and investigated programmed cell death response in colorectal cancer (CRC) cell, Caco-2. The scFv-M6-1B9 intrabody exhibits robust activity in reducing EMMPRIN cell surface expression. This approach led to the inducing of apoptosis, which was relative to the increasing of apoptotic bodies in sub-G1 peak, phosphatidylserine externalization, as well as TUNEL-positive cells. In addition, real-time RT-PCR and western blotting analysis indicated that apoptosis was enhanced through the mitochondrial pathway, a marked reduction of Bcl-2, leading to the translocation of cytochrome c and also the dramatic activation of caspase-3. Moreover, carcinoembryonic antigen (CEA), a tumor marker for CRC, was found to have significantly diminished in both secreted protein and mRNA levels. In conclusion, these findings suggest that EMMPRIN down-regulation by scFv-M6-1B9 intrabody has great potential in enhancing the efficacy of apoptosis induction through the mitochondrial pathway and in effecting a decline in the CEA level. Thus, its benefits could be applied to project the future prospects for targeted gene therapy and therapeutic application in monitoring colorectal cancer.

Anti-tumor activity of the beta-adrenergic receptor antagonist propranolol in neuroblastoma

Neuroblastoma (NB) is a pediatric tumor of the sympathetic nervous system, which is often associated with elevated catecholamines. More than half of patients with metastatic NB relapse and survival is extremely poor with current therapies. In a high-throughput screen of FDA-approved drugs we identified anti-NB activity for the nonselective β-adrenergic receptor antagonist propranolol hydrochloride.

Propranolol inhibited growth of a panel of fifteen NB cell lines irrespective of MYCN status, and treatment induced apoptosis and decreased proliferation. Activity was dependent on inhibition of the β2, and not β1, adrenergic receptor, and treatment resulted in activation of p53 and p73 signaling in vitro. The majority of NB cell lines and primary tumors express β2 adrenergic receptor and higher mRNA levels correlate with improved patient survival, but expression levels did not correlate with in vitro sensitivity to propranolol. Furthermore, propranolol is synergistic with the topoisomerase I inhibitor SN-38 and propranolol inhibits growth of NB xenografts in vivo at doses similar to those used to treat infants with hemangiomas and hypertension. Taken together, our results suggest that propranolol has activity against NB and thus should be considered in combination treatments for patients with relapsed and refractory NB.