Elucidating the roles of ASPM isoforms reveals a novel prognostic marker for pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers worldwide. Late diagnosis, desmoplastic tissue and intrinsic resistance to therapy are among the main reasons for its aggressive phenotype. In addition, it is now appreciated that cancer stem cells – a rare subpopulation of tumor cells highly resistant to therapy – are crucial players in PDAC initiation, progression and resistance to therapy. In a recent article in The Journal of Pathology, Hsu et al elucidated the specific roles of abnormal spindle-like, microcephaly-associated protein (ASPM) isoforms in PDAC. The authors reported that ASPM isoform I (ASPM-iI) is mainly expressed in the cytoplasm of PDAC cells. Its expression is associated with the Wnt signaling pathway, which promotes stemness and maintains the cancer stem cell niche. Clinically, expression of ASPM-iI correlates with poor survival in PDAC patients. Thus, this study revealed a novel prognostic marker as well as a potential therapeutic target for PDAC. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

BHLHB2 在人胰腺癌细胞株SU86.86的生物学功能研究

 【摘要】目的：进一步研究前期实验结果证明的人胰腺癌新颖的独立预后因子BHLHB2(cAMP -inducible basic helix-loop-helix domain containing, class B, 2) 在人胰腺癌细胞中的相关分子生物学功能。方法：应用siRNA干扰技术,在人胰腺癌细胞株SU86.86中使BHLHB2表达沉寂,然后进行迁徙实验,研究BHLHB2与细胞迁徙的关系;应用更生霉素（Actinomycin D,ACT-D)诱导细胞凋亡,研究BHLHB2与细胞凋亡的关系;应用Western Blot方法研究BHLHB2与EMT的相关性。结果: 人胰腺癌细胞BHLHB2 表达沉寂后,细胞的迁徙明显增快。应用ACT-D进行凋亡诱导,BHLHB2表达沉寂后、发生凋亡的细胞数目明显增加(10ng/ml, 增加 1.32倍, p<0.05; 100ng/ml, 增加 1.41倍, p<0.05)。Western Blot结果表明, BHLHB2表达沉寂后可显著降低E-cadherin的表达(降低 11.35 倍, p<0.01)。结论: BHLHB2 具有多种生物学功能,与人胰腺癌细胞的迁徙、细胞凋亡及EMT密切相关。     

Expression of Gli1 and Wnt2B correlates with progression and clinical outcome of pancreatic cancer

Objective: The aim of this study was to investigate the expression and clinical significance of Gli1 and Wnt2B in pancreatic cancer. Methods: We have constructed a formalin-fixed paraffin embedded pancreatic tissue microarrays 180cylindrical tissue cores of human pancreatic cancer and its paracancerous nonmalignant pancreatic specimens (NMPs) from 90 patients. Levels of Gli1 and Wnt2B were measured by immunohistochemistry. We analyzed the correlations between the expression of these factors and clinicopathological parameters including prognosis. Results: The expressions of both Gli1 and Wnt2B in human pancreatic cancer tissues were significantly higher than those of normal pancreatic tissues (P=0.000, P=0.004 respectively). The analysis showed that the high cytoplasmic expression levels of Gli1 in pancreatic cancer tissues had significant correlation with lymph node metastasis (P=0.036) and Wnt2B had significant correlation with perineural invasion (P=0.045). Gli1 and Wnt2B have no positive correlation. Survival analysis by Kaplan-Meier demonstrated that elevated Wnt2B expression in cancer tissue predicted worse overall survival (OS) compared with group in lower expression (P=0.024). No correlation was found between the expression of Gli1 and overall survival of pancreatic cancer patients (P>0.05). Conclusions: In conclusion, these results indicate that the high-expression levels of Gli1 and Wnt2B might play a pivotal role during tumorigenesis of pancreatic cancer, and the high expression of Wnt2B might be associated with poor prognosis.     

Wnt 信号通路和微生物在结直肠癌中的作用及意义

结直肠癌是临床上常见的恶性肿瘤之一,发病率在所有恶性肿瘤中排第3位,死亡率排第4位,对人类的健康造成了极大的威胁。近年来,在中国结直肠癌的发病率和死亡率均呈上升趋势,成为威胁人民健康的主要恶性肿瘤之一。结直肠癌发生和发展的机制非常复杂,涉及到的因素多种多样。例如,饮食、遗传、身体活动水平、环境等。目前具体致病机制还不十分清楚,这为结直肠癌的预防及治疗带来了极大的困难。随着分子生物学和分子遗传学的发展,已经明确 Wnt／β-catenin 信号通路在结直肠癌发生和发展中的重要作用。此外,越来越多的证据表明结直肠癌患者的肠道微生物群落与正常人存在明显不同,暗示了肠道微生物群与结直肠癌的关系。本文以 Wnt 信号通路和微生物为主线,总结它们之间的相互作用及在结直肠癌发生、发展和治疗中的作用。     

脂联素对人乳腺癌细胞株T47D细胞周期及凋亡的影响

目的 研究脂联素对人乳腺癌细胞株T47D细胞周期及凋亡的影响,探讨脂联素在乳腺癌发生发展中的作用.方法 采用噻唑蓝比色法检测不同浓度脂联素干预下T47D细胞的增殖情况,流式细胞分析仪分析细胞周期的变化,Annexin Ⅴ-FITC/PI染色法检测细胞凋亡.结果 (1)不同浓度脂联素和作用时间尽管对T47D细胞的生长有所抑制,但差异均没有统计学意义(P＞0.05).(2)脂联素浓度500 ng/ml、2000 ng/ml与0 ng/ml浓度相比较,对T47D细胞在G0/G1期的作用,总体差异有统计学意义(F=29.277,P=0.011),S期及G2/M期差异无统计学意义(F=3.968,P=0.144;F=0.233,P=0.806),两组浓度间比较也无显著性差异(P＞0.05).(3)脂联素浓度为0 ng/ml、500ng/ml、2000 ng/ml作用24 h后,T47D细胞的早期凋亡率分别为18.52％、18.75％和18.78％,3组比较无统计学差异(F=0.419,P=0.691).总凋亡率分别为24.58％、24.69％、24.11％,经统计学处理差异无统计学意义(F=0.099,P=0.909).结论 脂联素可将T47D细胞周期阻滞在G0/G1期,使S期细胞数量下降,抑制肿瘤细胞DNA合成.     

Zinc finger of the cerebellum 5 promotes colorectal cancer cell proliferation and cell cycle progression through enhanced CDK1/CDC25c signaling

IntroductionColorectal cancer (CRC), mostly caused by external or environmental factors, is the third most common and lethal cancer worldwide. Although a large number of investigations have been carried out to reveal the evolution of CRC, the underlying mechanisms of CRC remain unclear.Material and methodsExpression of zinc finger of the cerebellum 5 (ZIC5) in CRC tissues and cell models was measured by qRT-PCR and IHC. Cell transfection was carried out for ZIC5 overexpression or knockdown. The MTT assay was applied to examine the capacity of glioma cell proliferation. Wound healing assay and tumor invasion assay were used to test the capacity of glioma cell migration and invasion respectively. Cell cycle analysis and western blot were used to verify the apoptosis rates of CRC cells upon ZIC5 overexpression or downregulation. A further tumor Xenograft study was used to examine the effects of ZIC5 on tumor malignancy in vivo.ResultsCell models using HCT116 and SW620 cells were established to study the ZIC5 function upon ZIC5 overexpression of knockdown. Consistently, we discovered that ZIC5 also significantly increased in Chinese CRC patients. In addition, ZIC5 promoted CRC cell proliferation through increasing the proportion of cells maintained in the S phase. ZIC5 overexpression facilitated the capacity of CRC cell migration and invasion. Inhibition of ZIC5 mitigated such malignant effects.ConclusionsCollectively, investigations of the ZIC5 in CRC provided a new insight into CRC diagnosis, treatment, prognosis and next-step translational therapeutic developments from bench to clinic.     

Loss of expression of antigen-presenting molecules in human pancreatic cancer and pancreatic cancer cell lines

Tumours evade immune recognition and destruction through loss or down-regulation of expression of antigen processing and antigen-presenting molecules such as the human leucocyte antigen (HLA class I) and transporter for antigen presentation (TAP). This study examined the expression of HLA class I, class II and TAP in human pancreatic carcinoma tissue and 19 immortalized pancreatic cancer lines using a panel of antibodies directed against allele-specific as well as monomorphic determinants of these molecules. In tissue samples, reduction or loss of HLA class I and TAP was observed in 76% of cases, loss or down-regulation of TAP expression in 53%. In pancreatic cell lines down-regulation or loss of class I and TAP expression was also observed frequently. However, reductions in class I and TAP expression were reversible upon exposure to interferon-gamma in vitro, suggesting a regulatory rather than structural defect in these genes. De novo class II expression was observed in 26% of tumours and 42% of cell lines and may reflect the differentiation status of the cells. The high rate of class I and TAP loss has implications for immunotherapy strategies for pancreatic cancer, as such changes could facilitate a selective growth advantage for malignant cells. However, the reinduction of expression of these molecules with cytokines such as interferon-gamma may ultimately allow their cytotoxic T cell-mediated destruction.     

The complex pathways of Wnt 5a in cancer progression

In contrast to the transforming members of the Wnt family, shown to be upregulated in many cancers, the role of Wnt 5a is still controversial. While it has been attributed a tumour suppressor function in some malignancies, there is increasing evidence of promigratory and proinvasive effects in others, mediated predominantly through the planar cell polarity pathway and activation of protein kinase C. Obviously, the outcome of an individual Wnt 5a signal is dependent on a multitude of variables, ranging from availability of receptors, downstream effectors, and inhibitors to external influences coming from the tumour microenvironment and the extracellular matrix.     

Differential expression of heat shock protein 90 isoforms in small cell lung cancer

Heat shock protein 90 (HSP90), a molecular chaperone, plays important roles in cellular protection against various stressful stimuli and in the regulation of cellular growth and apoptosis. HSP90 has 4 different types of human isoforms; HSP90α, HSP90β, glucose related protein 94 (GRP94) and tumor necrosis factor (TNF) receptor-associated protein 1 (TRAP1). We assessed the differential expression of these HSP90 isoforms in small-cell lung cancer (SCLC) and the correlation of their expression levels with clinicopathological factors and patient survival rates. This study included 117 SCLCs, comprised of 108 primary and 9 metastatic tumor tissues. We performed immunohistochemical staining for HSP90α, HSP90β, GRP94 and TRAP1 in 117 tumors and found that HSP90α and HSP90β were positive in 11 (9%) and 61 tumors (52%), respectively, most of which showed weak expression, whereas GRP94 and TRAP1 were positive in 115 (98%) and 117 tumors (100%), respectively, the majority of which showed moderate or strong expression. None of the HSP90 isoforms showed significant associations with clinicopathological factors or survival status in patients with SCLC. Our results indicate that GRP94 and TRAP1 might contribute more to the carcinogenesis or biology of SCLC than HSP90α and HSP90β, and that isoform selectivity should be considered when HSP90 inhibitors are studied or utilized for the treatment of SCLC.     

Deciphering the role of hedgehog signaling in pancreatic cancer

Pancreatic cancer, mostly pancreatic ductal adenocarcinoma (PDAC), is a leading cause of cancer-related death in the US, with a dismal median survival of 6 months. Thus, there is an urgent unmet need to identify ways to diagnose and to treat this deadly cancer. Although a number of genetic changes have been identified in pancreatic cancer, their mechanisms of action in tumor development, progression and metastasis are not completely understood. Hedgehog signaling, which plays a major role in embryonic development and stem cell regulation, is known to be activated in pancreatic cancer; however, specific inhibitors targeting the smoothened molecule failed to improve the condition of pancreatic cancer patients in clinical trials. Furthermore, results regarding the role of Hh signaling in pancreatic cancer are controversial with some reporting tumor promoting activities whereas others tumor suppressive actions. In this review, we will summarize what we know about hedgehog signaling in pancreatic cancer, and try to explain the contradicting roles of hedgehog signaling as well as the reason(s) behind the failed clinical trials. In addition to the canonical hedgehog signaling, we will also discuss several non-canonical hedgehog signaling mechanisms.     

光动力疗法对子宫内膜癌Ishikawa细胞系细胞周期和凋亡的影响

目的 探讨光动力疗法(PDT)对子宫内膜癌Ishikawa细胞系细胞周期及凋亡的影响.方法 以四甲基吡啶卟啉(TMPyP)为光敏剂的PDT处理Ishikawa细胞,显微镜观察细胞形态;细胞计数试剂盒CCK-8检测细胞的存活率;流式细胞术检测细胞周期;使用Annexin V-FITC/PI凋亡检测试剂盒及流式细胞术检测细胞的凋亡;蛋白免疫印迹法检测Bcl-2、NF-κB P65及磷酸化NF-κB P65的表达.结果 PDT可以改变Ishikawa细胞的形态,降低细胞存活率(P＜0.05),并与光敏剂TMPyP的浓度和激光能量密度有关;PDT引起细胞S期阻滞(P＜0.05),诱导Ishikawa细胞发生凋亡(P＜0.05),降低Bcl-2蛋白的表达和NF-κB P65的磷酸化水平(P＜0.05).结论 PDT可能通过下调Bcl-2、NF-κB的活性引起Ishikawa细胞S期阻滞和细胞凋亡.     

62例胰腺癌组织中细胞凋亡的特征

目的研究拟阐明凋亡与胰腺癌分型、分期、分化程度、术后生存期的关系。方法62例胰腺癌标本取自1999年1月至2002年1月中国医科大学第二临床学院普外科及辽宁省人民医院普外科，术后病理证实。22例正常胰腺组织为上述医院的解剖标本。TUNEL法检测正常胰腺组织、胰腺癌组织内的凋亡细胞。结果在22例正常胰腺组织中细胞凋亡率为4／22，程度为（＋）；在62例胰腺癌组织中细胞凋亡阳性率为72．6％（45／62），程度为（＋）～（＋＋＋）。凋亡阳性率在胰腺癌组织分型、分期之间无统计学意义；高分化胰腺癌凋亡阳性率高于低分化胰腺癌（P〈0．05），中分化胰腺癌凋亡阳性率高于低分化胰腺癌（P〈0．01）；高、中分化胰腺癌之间差异无统计学意义；在中、高分化胰腺癌中，细胞凋亡程度（＋＋）～（＋＋＋）与（-）～（＋）的病例术后生存时间比较，前者显著长于后者（P〈0．05）。结论凋亡主要影响胰腺癌的发展、转移及预后；细胞凋亡在一定程度上阻止胰腺癌进展，最终延长胰腺癌患者生存时间。因此采用不同方法诱导胰腺癌组织中细胞凋亡可能为胰腺癌综合治疗提供新思路。     

The canonical Wnt signaling pathway plays an important role in lymphopoiesis and hematopoiesis

The evolutionarily conserved canonical Wnt-beta-catenin-T cell factor (TCF)/lymphocyte enhancer binding factor (LEF) signaling pathway regulates key checkpoints in the development of various tissues. Therefore, it is not surprising that a large body of gain-of-function and loss-of-function studies implicate Wnt-beta-catenin signaling in lymphopoiesis and hematopoiesis. In contrast, recent papers have reported that Mx-Cre-mediated conditional deletion of beta-catenin and/or its homolog gamma-catenin (plakoglobin) did not impair hematopoiesis or lymphopoiesis. However, these studies also report that TCF reporter activity remains active in beta-catenin- and gamma-catenin-deficient hematopoietic stem cells and all cells derived from these precursors, indicating that the canonical Wnt signaling pathway was not abrogated. Therefore, these studies in fact show that the canonical Wnt signaling pathway is important in hematopoiesis and lymphopoiesis, even though the molecular basis for the induction of the reporter activity is currently unknown. In this perspective, we provide a broad background to the field with a discussion of the available data and create a framework within which the available and future studies may be evaluated.     

过表达IL-18的T细胞对胰腺癌细胞SW-1990的杀伤作用

目的探讨IL-18基因过表达的T细胞对胰腺癌细胞系SW1990的杀伤作用。方法用PCR技术构建含IL-18基因的重组慢病毒,HEK293T细胞包装后感染分离培养的人T淋巴细胞,与胰腺癌细胞SW-1990共培养后,检测培养上清中的LDH含量、ELISA检测IL-2和IFN-γ的含量,以间接评估其对SW-1990细胞体外的杀伤作用。结果成功构建和包装了人IL-18的重组慢病毒,感染人T淋巴细胞后,在与人胰腺癌细胞SW-1990共培养条件下,与空白对照组相比,LDH的释放显著增多(P0.01);IL-2和IFN-γ的分泌亦显著增多(P0.01)。结论过表达人IL-18蛋白的T淋巴细胞对胰腺癌细胞SW-1990具有更强的杀伤作用。     

IGFBP-2对人胶质瘤细胞的恶性增殖和细胞周期进程的影响

目的研究IGFBP-2的表达水平对胶质瘤细胞系增殖和细胞周期进程的作用。方法采用免疫印迹筛选IGFBP-2高表达的胶质瘤细胞系,设计并合成IGFBP-2特异的siRNA,将其导入筛选出的胶质瘤细胞系,采用实时定量PCR和免疫印迹验证IGFBP-2的表达下调情况,随后采用MTT实验的流式细胞技术检测IGFBP-2的下调对细胞增殖和细胞周期进程的影响情况。结果合成的IGFBP-2特异siRNA能够显著降低胶质瘤细胞系IGFBP-2的表达,siRNA介导的IGFBP-2的表达下调能够显著抑制胶质瘤细胞的增殖和细胞周期的推进(0.01)。结论 IGFBP-2对胶质瘤细胞的恶性表型具有促进作用,为进一步探讨IGFBP-2影响胶质瘤细胞行为学的机制奠定了基础。     

CyclinB1 deubiquitination by USP14 regulates cell cycle progression in breast cancer

Breast cancer is the most common malignant tumor among women in China, which seriously threatens women's physical and mental health. Tumorigenesis is closely related to the dysregulation of cell cycle. The cell cycle progression includes interphase and mitotic phase (M phase). Cyclin B1 is a key protein in regulating M phase, which is essential for the whole cell cycle progression. CyclinB1 can be degraded through ubiquitination mediated by the anaphase promoting complex/cyclosome (APC/C). However, the mechanism of how CyclinB1 is deubiquitinated in breast cancer still remains unclear. In this study, we discovered that CyclinB1 interacted with ubiquitin-specific peptidase 14 (USP14). Based on the deubiquitinating function of USP14, we detected the effect of USP14 on the ubiquitination of CyclinB1. Inhibiting the activity of USP14 or USP14 knockdown significantly increased the ubiquitination of CyclinB1. In accordance with this, knocking down USP14 arrested cell cycle at G2/M phase. Knocking down USP14 with siRNAs significantly inhibited the proliferation and migration of breast cancer cells. In conclusion, our study demonstrated that USP14 regulated the cell cycle of breast cancer cells by regulating the ubiquitination of CyclinB1, which will provide a solid theoretical basis for the development of anti-cancer drugs targeting USP14.     

MCPIP1诱导乳腺癌细胞系MDA-MB-231细胞周期停滞

目的研究单核细胞趋化蛋白诱导蛋白1(MCPIP1)在乳腺癌细胞MDA-MB-231中的作用及机制。方法用脂质体转染法转染细胞,在MDA-MB-231中分别过表达,或敲低MCPIP1并筛选稳定表达shRNA的单克隆;MTT法检测细胞增殖;流式细胞计量技术检测细胞周期;实时荧光定量PCR(q-PCR)检测靶基因半衰期;RNA免疫沉淀法(RNA-IP)检测MCPIP1结合的靶基因;荧光素酶报告基因实验检测调节基因3'非编码区(3'UTR)的能力。结果过表达MCPIP1可显著抑制MDA-MB-231细胞增殖(P0.05),敲低MCPIP1显著促进细胞增殖(P0.05);并分别显著增加或降低G1期细胞百分比(P0.01);MCPIP1显著降低细胞周期素依赖性激酶2(CDK2)、细胞周期素依赖性激酶6(CDK6)、cyclin D1和cyclin E1 mRNAs的半衰期(P0.01);MCPIP1结合细胞周期相关基因(P0.05);MCPIP1显著降低含不同3'UTR的报告基因荧光素酶活性(P0.05)。结论MCPIP1在乳腺癌细胞MDA-MB-231中发挥抑癌作用,诱导细胞周期G_1期停滞可能是其发挥抑癌功能的机制之一。     

VEGF-C表达与胰腺癌淋巴结转移及预后的关系

目的 观察血管内皮生长因子(VEGF)-C在胰腺癌组织内的表达情况,分析VEGF-C的表达与胰腺癌淋巴结转移和预后之间的关系。方法 取胰腺癌病例52例,其中,伴淋巴结转移组36例,无淋巴结转移组16例。应用免疫组化法和Western blot技术观察VEGF-C在胰腺癌组织内的表达。以D2-40作为淋巴管内皮特异性标记物,观察胰腺癌组织内淋巴管生成的情况。采用Kaplan-Meier法绘制生存曲线判断VEGF-C的表达对胰腺癌预后的影响。结果 Western blot和免疫组化法检测结果表明,VEGF-C主要表达于胰腺癌细胞浆内,淋巴结转移组阳性表达量明显高于无淋巴结转移组(p<0.05)。D2-40表达于胰腺癌组织内淋巴管内皮细胞,VEGF-C阳性组淋巴管数密度明显高于VEGF-C阴性组(p<0.05),表明VEGF-C的表达与胰腺癌淋巴管生成密切相关。Kaplan-Meier生存分析表明VEGF-C表达阴性患者的生存率均高于VEGF-C表达阳性患者,VEGF-C的表达影响患者的预后。结论 VEGF-C在胰腺癌的淋巴管生成和淋巴结转移过程中发挥重要作用,VEGF-C的表达是影响胰腺癌患者预后的主要因素之一。