Hepatocellular carcinoma: Where there is unmet need

Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor most commonly associated with underlying chronic liver disease, especially hepatitis. It is a growing problem in the United States and worldwide. There are two potential ways to prevent HCC. Primary prevention which is based on vaccination or secondary prevention involving agents that slow down carcinogenesis. Several pathways have been thought to play a role in the development of HCC; specifically, those involving vascular endothelial growth factor (VEGF)‐mediated angiogenesis, WNT, phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR), AMP‐activated protein kinase (AMPK), and c‐MET. Currently, there are only a limited number of drugs which have been proven as effective treatment options for HCC and several clinical trials are testing drugs which target aberrations in the pathways mentioned above. In this review, we discuss currently approved therapies, monotherapies and combination therapy for the treatment of HCC.     

Preclinical Evaluation of MET Inhibitor INC-280 With or Without the Epidermal Growth Factor Receptor Inhibitor Erlotinib in Non–Small-Cell Lung Cancer

BackgroundAlthough the epidermal growth factor receptor (EGFR) inhibitor erlotinib is initially effective in non–small-cell lung cancer (NSCLC) patients with tumors harboring activating mutations of EGFR, most subsequently develop acquired resistance. One recognized resistance mechanism occurs through activation of bypass signaling via the hepatocyte growth factor (HGF)-MET pathway. INC-280 is a small molecule kinase inhibitor of MET. We sought to demonstrate the activity of INC-280 on select NSCLC cell lines both as a single agent and in combination with erlotinib using exogenous HGF to simulate MET up-regulation.MethodsFour NSCLC cell lines (HCC827, PC9, H1666, and H358) were treated with either single-agent INC-280 or in combination with erlotinib with or without HGF. The activity of the drug treatments was measured by cell viability assays. Immunoblotting was used to monitor expression of EGFR/pEGFR, MET/pMET, GAB1/pGAB1, AKT/pAKT, and ERK/pERK as well as markers of apoptosis (PARP and capase-3 cleavage) in H1666, HCC827, and PC9.ResultsAs a single agent, INC-280 showed minimal cytotoxicity despite potent inhibition of MET kinase activity at concentrations as low as 10 nM. Addition of HGF prevented erlotinib-induced cell death. The addition of INC280 to HGF-mediated erlotinib-resistant models restored erlotinib sensitivity for all cell lines tested, associated with cleavage of both PARP and caspase-3. In these models, INC-280 treatment was sufficient to restore erlotinib-induced inhibition of MET, GAB1, AKT, and ERK in the presence of HGF.ConclusionAlthough the MET inhibitor INC-280 alone had no discernible effect on cell growth, it was able to restore sensitivity to erlotinib and promote apoptosis in NSCLC models rendered erlotinib resistant by HGF. These data provide a preclinical rationale for an ongoing phase 1 clinical trial of erlotinib plus INC-280 in EGFR-mutated NSCLC.     

Metadherin regulates metastasis of squamous cell carcinoma of the head and neck via AKT signalling pathway-mediated epithelial–mesenchymal transition

Our recent study suggested that metadherin (MTDH) is overexpressed in laryngeal squamous cell carcinoma. Here, we further investigated its role in promoting metastasis of squamous cell carcinoma of the head and neck (SCCHN). An immunohistochemistry analysis demonstrated that MTDH is elevated and positively correlated with metastasis in 189 primary SCCHN tissues. In vitro experiments demonstrated that MTDH overexpression enhanced the migratory and invasive ability of SCCHN cells. Moreover, MTDH induced epithelial–mesenchymal transition (EMT) by both regulating morphological changes and mediating the expression of the biomolecular makers E-cadherin and vimentin. In addition, MTDH mediated AKT activation, and all of the above effects were nearly completely blocked by the inhibition of AKT. Our results suggested that MTDH might promote the metastasis of SCCHN through AKT signalling pathway mediated-EMT.     

The rationale for mTOR inhibition in epithelial ovarian cancer

The AKT/mTOR signaling pathway is frequently overexpressed in human epithelial ovarian cancer and an attractive target for therapy. In vivo mouse models were confirmative for in vitro findings, where the administration of mTOR inhibitors in ovarian cancer xenografts showed antitumoral as well as antiangiogenic effects. Phase I – II trials are now ongoing with mTOR inhibitors in ovarian cancer patients, some in combination with conventional cytotoxic agents. If further development of mTOR inhibition in ovarian cancer is pursued, studying combinations of mTOR inhibitors with other new targeted therapies would be of interest. mTOR inhibitors in the adjuvant setting could have potential, since, for the moment, there is no standard maintenance therapy in ovarian cancer. A crucial challenge will be to identify strong predictive biomarkers. This review highlights the rationale for the use of mTOR inhibitors in ovarian cancer and summarizes the available preclinical findings.     

Autocrine insulin-like growth factor 1 and stem cell factor but not interleukin 6 support self-renewal of human myeloma cells

In this study, we have identified the growth factors supporting myeloma self-renewal in eight myeloma cell lines. All cell lines able to form self-colonies displayed constitutive P-AKT and P-ERK1,2 but not P-STAT3 and did not express CD45, suggesting the presence of an insulin-like growth factor 1 (IGF1) loop. We showed that a blocking anti-insulin-like growth factor 1 receptor (IGF1R) monoclonal antibody (mAb) inhibited colony formation in correlation with IGF1R expression and decreased P-AKT. Imatinib or a blocking anti-stem cell factor (SCF) mAb also inhibited colony formation of two cell lines expressing C-KIT and SCF, and decreased P-AKT. Moreover, the PI3K/AKT pathway inhibitor wortmannin inhibited colony formation. Blocking interleukin (IL)6R did not inhibit colony formation in good agreement with a lack of constitutive P-STAT3. We showed that primary cells frequently co-expressed IGF1R/IGF1 but not C-KIT/SCF or IL6R/IL6, suggesting that in vivo autonomous growth could be possible via IGF1R. Despite their similar role in clonogenic growth and shared signaling pathway, IGF1R and C-KIT had opposite prognostic values, suggesting that they were surrogate markers. Indeed, we showed that both C-KIT and IGF1R prognostic values were not independent of MMSET expression. This study highlights the autocrine role of IGF1 in myeloma cells and reinforces the interest in targeting IGF1R in IGFR1⁺ CD45^+/− patients, such as MMSET⁺ patients.     

西黄丸组分中药调节肿瘤微环境中Treg细胞PI3K/AKT通路的抗肿瘤作用机制研究

目的 研究西黄丸组分中药是否与西黄丸具有相似的抗癌作用及机制。方法 4T1乳腺癌细胞荷瘤建立动物模型,西黄丸低、中、高剂量（0.39、0.78、1.95 g/kg）和西黄丸组分中药0.3 mL （74.5 mg/kg榄香烯、2.73 mg/kg牛磺酸、0.52mg/kg麝香酮和4.75 mg/kg 11-羰基-β乙酯乳香酸混合物,对应于西黄丸高剂量组） ig给药14 d,剥离肿瘤组织,称质量,匀浆,制备单细胞悬液,免疫磁硃分离Treg细胞。流式细胞术和免疫组化检测肿瘤微环境中Treg细胞数量变化情况,Western Blotting检测肿瘤微环境中Treg细胞磷脂酰肌醇3-激酶/蛋白激酶B （PI3K/AKT）蛋白表达情况,实时荧光定量PCR （qRT-PCR）检测肿瘤微环境中Treg细胞PI3K、AKT mRNA表达情况。结果 与模型组及西黄丸低、中剂量组比较,西黄丸组分中药组肿瘤质量显著减少（P<0.05）;流式细胞术和免疫组化结果显示,肿瘤微环境中Treg细胞数量显著减少（P<0.05）;Western Blotting和qRT-PCR结果显示,肿瘤微环境中Treg细胞PI3K、AKT蛋白及mRNA表达显著下降（P<0.05）。与西黄丸高剂量组比较,西黄丸组分中药组肿瘤质量、Treg细胞数量和PI3K、AKT蛋白及mRNA表达均明显升高（P<0.05）。结论 西黄丸组分中药通过抑制肿瘤微环境中Treg细胞PI3K/AKT信号通路的表达减少Treg细胞数量,进而表现与西黄丸相似的抗癌作用和机制。     

S-allyl-l-cysteine attenuates bleomycin-induced pulmonary fibrosis and inflammation via AKT/NF-κB signaling pathway in mice

Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterized by inflammation, multifocal fibrotic lesions and excessive collagen deposition with limited therapies. As a major bioactive compound in garlic, S-allyl-l-cysteine (SAC) is a neuroprotective drug candidate to prevent cognitive decline, however, its anti-pulmonary fibrotic activity remains unknown. Here, we investigated whether SAC could attenuate bleomycin (BLM)-induced pulmonary fibrosis and inflammation in mice. Our results showed that SAC dose-dependently reduced the infiltration of inflammatory cells, pulmonary lesions and collagen deposition in BLM treated mice with downregulated mRNA expression levels of fibrotic genes including alpha smooth muscle actin (α-SMA), fibronectin, collagen I and collagen III as well as the protein level of α-SMA. In addition, SAC could also reduce the mRNA expression of inflammatory mediators such as TNF-α and iNOS. Furthermore, higher phosphorylation of AKT and NF-κB p65 in IPF patient samples and murine samples was verified by immunohistochemistry while SAC could decrease the phosphorylation level of AKT and NF-κB p65 in mice stimulated with BLM. These findings, for the first time, indicate that SAC might mediate AKT/NF-κB signaling pathway to inhibit BLM-induced pulmonary fibrosis and support the potential role of SAC as an anti-pulmonary fibrosis agent.     

汉黄芩苷对柯萨奇B3病毒诱导的病毒性心肌炎小鼠炎症反应的影响

目的:探讨汉黄芩苷对柯萨奇B3病毒(CVB3)诱导的病毒性心肌炎小鼠炎症反应的影响及其可能的调控机制。方法:用CVB3感染BALB/c小鼠构建病毒性心肌炎动物模型。取40只BALB/c小鼠将其随机分为4组:正常对照组、CVB3感染的病毒性心肌炎组、CVB3感染后给予汉黄芩苷处理的治疗组以及CVB3感染后同时给予汉黄芩苷和AKT激动剂处理的激动剂组,每组10只。于药物治疗7 d后处死各组小鼠。用HE染色检测前3组小鼠心肌组织内炎症细胞浸润情况。用ELISA检测前3组小鼠血清中白细胞介素1β(IL-1β)和IL-6含量。用Western blot实验检测前3组小鼠心脏组织中炎症因子蛋白表达水平以及AKT/NF-κB通路的活化情况。最后,通过Western blot实验检测全部4组小鼠心肺组织中AKT/NF-κB通路的活化情况。结果:与正常组相比,病毒性心肌炎小鼠心脏组织内存在大量炎症细胞浸润,而汉黄芩苷治疗显著降低CVB3病毒诱导的心脏组织炎症细胞浸润(P<0.05)。CVB3病毒感染后小鼠血清中IL-1β和IL-6含量较正常组显著升高(P<0.05),而给予汉黄芩苷治疗后小鼠血清中IL-1β和IL-6含量较病毒性心肌炎组显著降低(P<0.05)。Western blot检测结果表明,与病毒性心肌炎组相比,汉黄芩苷治疗显著降低心肌组织内炎症因子(IL-1β和IL-6)蛋白表达水平以及AKT和NF-κB蛋白的磷酸化水平(P<0.05);而给予AKT激动剂处理后,汉黄芩苷对NF-κB蛋白磷酸化水平的抑制作用显著减弱(P<0.05),且汉黄芩苷对炎症因子的下调作用也显著受到抑制(P<0.05)。结论:汉黄芩苷可通过调控AKT/NF-κB通路减轻病毒性心肌炎小鼠的炎症反应。     

基于ILK信号通路探究马桑水提取物影响大鼠烧伤创面愈合和瘢痕增生的机制

目的:基于整合素连接激酶(ILK)调控的转化生长因子β1(TGF-β1)和PI3K/AKT调控的ILK等互通信号通路,探究马桑水提取物(CSME)促进大鼠烧伤创面早期愈合和抑制后期瘢痕过度增生的机制。方法:随机将180只SD雌性大鼠(180~200 g)分成正常对照(NC)组、凡士林(VL)组、磺胺嘧啶银(SS)组及CSME低、中和高剂量(CSME-L、CSME-M和CSME-H)组,每组各30只。大鼠以水合氯醛麻醉,腰背部II°烫伤造模后,每天分别在创面涂擦VL、SS和3种剂量的CSME烧伤软膏,计算创面愈合率(HR),于第7、14和21天随机选取各组动物10只,水合氯醛麻醉,切取创面皮肤,病理学观查,Western blot检测相关蛋白表达,RT-qPCR检测相关mRNA表达,培养成纤维细胞检测其胶原收缩率(SK)。结果:在第7天,CSME各组创面中ILK、纤维连接蛋白(FN)、TGF-β1、α-平滑肌肌动蛋白(α-SMA)和整合素β1(integrin-β1,ITG-β1)的蛋白与mRNA表达呈现剂量依赖性强于VL和SS组,第21天,弱于VL和SS组(P<0.05);第14天,CSME各组组织中I型胶原蛋白(Col I)的蛋白与mRNA表达呈剂量依赖性强于VL和SS组,第21天则弱于VL和SS组(P<0.05),而III型胶原蛋白(Col III)的蛋白与mRNA表达呈剂量依赖性弱于VL和SS组,第21天则强于VL和SS组(P<0.05);随时间推移,VL和SS组成纤维细胞的SK持续升高,96 h达高峰,而CSME各组在24 h和48 h呈剂量依赖性高于VL和SS组,在96 h呈剂量依赖性低于VL和SS组(P<0.05)。结论:CSME早期促进烧伤创面愈合,后期抑制创面瘢痕过度增生,其机制与其多成分多靶点影响ILK调控的TGF-β1和PI3K/AKT调控的ILK信号通路及ColⅠ与Col III表达比的调控相关。