The tyrosine kinase inhibitor nilotinib has antineoplastic activity in prostate cancer cells but up-regulates the ERK survival signal—Implications for targeted therapies

BackgroundNovel therapeutic options beyond hormone ablation and chemotherapy are urgently needed for patients with advanced prostate cancer. Tyrosine kinase inhibitors (TKIs) are an attractive option as advanced prostate cancers show a highly altered phosphotyrosine proteome. However, despite favorable initial clinical results, the combination of the TKI dasatinib with docetaxel did not result in improved patient survival for reasons that are not known in detail.MethodsThe National Cancer Institute–Approved Oncology Drug Set II was used in a phenotypic drug screen to identify novel compounds with antineoplastic activity in prostate cancer cells. Validation experiments were carried out in vitro and in vivo.ResultsWe identified the TKI nilotinib as a novel compound with antineoplastic activity in hormone-refractory prostate cancer cells. However, further analyses revealed that treatment with nilotinib was associated with a significant up-regulation of the phospho-extracellular-signal-regulated kinases (ERK) survival signal. ERK blockade alone led to a significant antitumoral effect and enhanced the cytotoxicity of nilotinib when used in combination.ConclusionsOur findings underscore that TKIs, such as nilotinib, have antitumoral activity in prostate cancer cells but that survival signals, such as ERK up-regulation, may mitigate their effectiveness. ERK blockade alone or in combination with TKIs may represent a promising therapeutic strategy in advanced prostate cancer.     

Diverse immune functions of hemocyanins

Substantial evidence gathered recently has revealed the multiple functionalities of hemocyanin. Contrary to previous claims that this ancient protein is involved solely in oxygen transport within the hemolymph of invertebrates, hemocyanin and hemocyanin-derived peptides have been linked to key aspects of innate immunity, in particular, antiviral and phenoloxidase-like activities. Both phenoloxidase and hemocyanin belong to the family of type-3 copper proteins and share a high degree of sequence homology. While the importance of phenoloxidase in immunity and development is well characterised, the contribution of hemocyanin to biological defence systems within invertebrates is not recognised widely.     

茯苓多糖对人宫颈癌HeLa细胞增殖、迁移、促凋亡的影响及其机制

目的 探讨茯苓多糖（Pachymaran）对人宫颈癌HeLa细胞增殖、迁移、促凋亡的作用及其相关机制。方法 MTT法检测细胞增殖率并筛选出适宜的茯苓多糖低、中、高浓度用于后续实验；不同浓度的茯苓多糖处理细胞后，倒置相差显微镜观察细胞形态学变化；Hoechst 33342染色观察细胞核的变化；平板克隆实验检测细胞克隆形成能力；细胞划痕实验检测细胞迁移能力；流式细胞术检测细胞凋亡率及细胞周期；Western blot法检测凋亡、迁移及ERK通路相关蛋白的表达。结果 茯苓多糖浓度对HeLa细胞活力的影响实验得出，取30、40、50 mg/ml茯苓多糖作为低、中、高浓度进行后续实验；中、高浓度茯苓多糖处理细胞后，细胞和细胞核发生显著的凋亡形态学变化，低浓度下形态学变化不显著；不同浓度茯苓多糖均能降低细胞克隆形成能力；降低细胞迁移率（P<0.05）；使细胞凋亡率增加（P<0.05）；使S期细胞减少并阻滞于G₂/M期（P<0.05）；Cleaved Caspase 3、Cleaved Caspase 8、Cleaved Caspase 9、Bax表达较对照组明显增多，Bcl-2、MMP-9、VEGFA、p-ERK1/2表达明显减少（P<0.05）。ERK1/2表达无明显变化。结论 茯苓多糖能显著抑制HeLa细胞增殖，并诱导其凋亡。其促凋亡机制可能与下调p-ERK1/2表达，抑制ERK信号通路磷酸化有关。同时，茯苓多糖对抑制HeLa细胞的迁移也有一定的作用。     

Targeting the PI3K/AKT/mTOR pathway in biliary tract cancers: A review of current evidences and future perspectives

Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches.The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes.Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy.This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors.     

p-ERK2及ERK2在鼻息肉组织的表达及其意义

目的 检测磷酸化细胞外信号调节激酶2(p-ERK2)及细胞外信号调节激酶2(ERK2)在鼻息肉(NP)组织的定位及表达情况;初步探讨p-ERK2/ERK2在NP发病中的临床意义。 方法 应用间接免疫荧光技术(IIF)及蛋白免疫印记技术(WB)检测p-ERK2/ERK2在NP及正常鼻黏膜组织的定位及表达水平,并探讨其临床意义。 结果 NP:p-ERK2主要表达在增生的上皮细胞、炎症细胞以及腺上皮细胞,主要位于胞核;ERK2主要表达在腺上皮细胞、炎症细胞,主要位于胞质。正常鼻黏膜组织:p-ERK2主要表达在炎症细胞、腺上皮细胞,主要位于胞核;ERK2主要位于炎症细胞,主要位于胞质。荧光强度值:p-ERK2在NP和正常鼻黏膜组织的表达有统计学差异(P<0.05);ERK2在NP和正常鼻黏膜组织的表达无统计学差异(P>0.05)。WB灰度值:p-ERK2在NP和正常鼻黏膜组织的表达有统计学差异(P<0.05);ERK2在NP和正常鼻黏膜组织的表达无统计学差异(P>0.05)。 结论 p-ERK2在NP的发病机制中可能具有重要作用,而ERK2与NP的发生可能无关。ERK2在NP组及正常鼻黏膜组织均表达,提示ERK2可能参与鼻黏膜正常生理功能的维持。     

Anxa5 mediates the in vitro malignant behaviours of murine hepatocarcinoma Hca-F cells with high lymph node metastasis potential preferentially via ERK2/p-ERK2/c-Jun/p-c-Jun(Ser73) and E-cadherin

ObjectiveAnnexin A5 (Anxa5) is associated with the progression of some cancers, while its role and regulation mechanism in tumor lymphatic metastasis is rarely reported. This study aims to investigate the influence of Anxa5 knockdown on the malignant behaviours of murine hepatocarcinoma Hca-F cell line with high lymph node metastatic (LNM) potential and the underlying regulation mechanism.MethodsRNA interfering was performed to silence Anxa5 in Hca-F. Monoclonal shRNA-Anxa5- Hca-F cells were obtained via G418 screening by limited dilution method. Quantitative real-time RT-PCR (qRT-PCR) and Western blotting (WB) were applied to measure Anxa5 expression levels. CCK-8, Boyden transwell-chamber and in situ LN adhesion assays were performed to explore the effects of Anxa5 on the proliferation, migration, invasion and adhesion capacities of Hca-F. WB and qRT-PCR were used to detect the level changes of key molecules in corresponding signal pathways.ResultsWe obtained two monoclonal shRNA-Anxa5-transfected Hca-F cell lines with stable knockdowns of Anxa5. Anxa5 knockdown resulted in significantly reduced proliferation, migration, invasion and in situ LN adhesion potentials of Hca-F in proportion to its knockdown extent. Anxa5 downregulation enhanced E-cadherin levels in Hca-F. Moreover, Anxa5 affected Hca-F behaviours specifically via ERK2/p-ERK2/c-Jun/p-c-Jun(Ser73) instead of p38MAPK/c-Jun, Jnk/c-Jun and AKT/c-Jun pathways.ConclusionsAnxa5 mediates the in vitro malignant behaviours of murine hepatocarcinoma Hca-F cells via ERK2/c-Jun/p-c-Jun(Ser73) and ERK2/E-cadherin pathways. It is an important molecule in metastasis (especially LNM) and a potential therapeutic target for hepatocarcinoma.     

TGF-β3 and IGF-1 synergy ameliorates nucleus pulposus mesenchymal stem cell differentiation towards the nucleus pulposus cell type through MAPK/ERK signaling

Abstract

This study aimed to investigate the synergy between transforming growth factor beta 3 (TGF-β3) and insulin-like growth factor 1 (IGF-1) on nucleus pulposus-derived mesenchymal stem cells (NP-MSCs) and the underlying mechanism using a serum-free culture system. NP-MSC proliferation and viability were measured using a CCK-8 assay and annexin V-FITC/propidium iodide, respectively. NP-MSCs in micromasses were investigated for differentiation towards nucleus pulposus cells (NPCs). SOX-9, collagen-I, collagen-II, aggrecan and decorin expressions were detected by RT-PCR and immunoblotting. Matrix deposition was assessed by sulfated glycosaminoglycan (sGAG) analysis. Novel chondrogenic and nucleus pulposus (NP) genes were detected to distinguish differentiated cell types. MAPK/ERK and TGF/Smad signaling pathways were also examined. As a result, the synergy between TGF-β3 and IGF-1 enhanced NP-MSC viability, extracellular matrix (ECM) biosynthesis and differentiation towards NPCs, partly through the activation of the MAPK/ERK signaling pathway. Therefore, the synergy between TGF-β3 and IGF-1 ameliorates NP-MSC viability, differentiation and promotes intervertebral disc regeneration.