Knockdown of KDM1B inhibits cell proliferation and induces apoptosis of pancreatic cancer cells

Pancreatic cancer (PC) is one of the common malignant tumors in digestive tract with a high fatality rate. The oncogenic role of lysine-specific demethylase1 (LSD1/KDM1?A) has been well recognized in PC. While, the role of its homolog LSD2 (KDM1B) in regulating PC progression is poorly understood. In this study, we attempted to evaluate the functional role of KDM1B in PC cells. The expression of KDM1B was detected by immunohistochemistry and immunoblotting in PC tissues and cells. Lentivirus-mediated shRNA was applied to silence KDM1B in PANC-1 and SW1990 cells. Cell proliferation was measured by MTT and Celigo assay. Cell apoptosis was determined by both Caspase-Glo^®3/7 assay and Flow cytometry. Intracellular signaling molecules were detected using a PathScan intracellular signaling array kit. In this study, we found KDM1B was highly expressed in PC tissues compared to paracancerous tissues. Moreover, elevated expression of KDM1B was detected in PC cell lines (BxPC-3, CFPAC-1, PANC-1 and SW1990) as compared with a normal human pancreatic duct epithelial cell line (HPDE6-C7). Further investigations revealed that KDM1B knockdown significantly inhibited PC cell proliferation. Furthermore, the apoptosis of PANC-1 and SW1990 cells was significantly increased after KDM1B knockdown. Notably, the activations of p-ERK1/2, p-Smad2, p-p53, cleaved PARP, cleaved Caspase-3, cleaved Caspase-7, p-eIF2a and Survivin were promoted by KDM1B knockdown, while IkBa was suppressed. Taken together, our findings provided new insights into the critical and multifaceted roles of KDM1B in the regulation of cell proliferation and apoptosis, and offered a potentially novel target in preventing the progression of PC.     

基于网络药理学的康莱特注射液3种主要成分抗肿瘤机制研究

目的 利用网络药理学分析康莱特注射液3种主要成分的抗肿瘤作用机制。方法 以康莱特注射液中具有抗肿瘤作用的甘油三油酸酯、薏苡仁酯、薏苡素为研究对象，依托中药系统药理学数据库（TCMSP）、反向分子对接服务器（PharmMapper）、人类基因组注释数据库（GeneCards）、药物治疗靶标数据库（TTD）进行靶点预测和筛选，借助Cytoscape 3.5.1软件构建活性成分-靶点-疾病网络，借助STRING平台构建靶蛋白相互作用网络，通过DAVID平台对靶点基因本位生物过程和KEGG信号通路进行富集分析。结果 康莱特注射液活性成分作用于EGFR、PGR、PTGS2、AR、MAPK1等25个潜在抗肿瘤靶点，调控FoxO、前列腺癌、癌症、Rap1、TNF、Ras、MAPK信号通路，参与细胞增殖调控、蛋白激酶B信号调控、环氧合酶途径、细胞迁移调控等生物过程，可用于20多种癌症的治疗。结论 本研究为进一步深入研究康莱特注射液抗肿瘤机制提供了新的线索与思路。     

两种保留自主神经D3根治术治疗中低位直肠癌的安全性及生存质量比较

目的比较腹腔镜保留自主神经D3根治术与开腹术治疗中低位直肠癌的安全性及生存质量差异。 方法回顾性分析2015年6月至2017年8月间84例低位直肠癌患者资料，根据手术方式不同分为腹腔镜组(n＝46)和开腹组(n＝38)，应用SPSS21.0软件完成数据分析。手术相关指标采用( ±s)表示，独立样本t检验；并发症发生率、复发率及生存率等指标采用χ²检验；P<0.05为差异有统计学意义。 结果腹腔镜组患者的手术时间长于开腹组(P<0.05)，而术中出血量、住院时间、尿管保留时间、肛门排气时间均短于开腹组(均P<0.05)。腹腔镜组术后并发症总发生率为6.5%低于开腹组的26.3%(χ²＝4.6517，P<0.05)。两组患者1年局部复发率及生存率差异均无统计学意义(均P>0.05)。腹腔镜组患者术后10 d排尿功能、术后2个月勃起功能、术后2个月射精功能均优于开腹组(均P<0.05)。 结论腹腔镜保留自主神经D3根治术治疗中低位直肠癌安全性较高，复发率及生存率与开腹术相当，并能显著提高患者的生存质量，值得推广应用。     

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。     

围产期PFOS暴露对幼鼠海马BDNF/TrkB/CREB信号通路影响

目的 探讨观察母孕鼠围产期全氟辛烷磺酸盐(perfluorooctane sulphonate,PFOS)暴露对幼鼠海马组织BDNF/TrkB/CREB信号通路关键基因表达的影响。 方法 20只昆明种雌性小鼠随机分为对照组和低、中、高剂量组,从孕鼠怀孕第2 d开始(gestation day2, GD2)到幼鼠出生后21 d(postnatal day21,PND21)分别给予低、中、高剂量组孕鼠PFOS剂量为 0.1、1.0、5.0 mg/(kg·bw)灌胃染毒,对照组给予等体积的0.05% Tween-20水溶液。灌胃量为0.1 ml/10 (g·bw)。PND 21 d处死幼鼠,收集脑组织,分离海马及皮层。HE染色观察脑组织常规病理改变,实时荧光定量PCR(Quantitative Real-time PCR,QPCR)检测海马组织中BDNF、TrkB、CREB、Syn1及Syp的mRNA表达水平。 结果 与对照组相比较,低、中、高三个剂量组对幼鼠的死亡率和体质量的影响差异无统计学意义(P>0.05)。但是在高剂量组幼鼠海马组织出现空泡,海马BDNF、TrkB、CREB mRNA水平显著降低,分别由对照组的(0.98±0.11)、(1.03±0.09)、(1.08±0.12)下降到(0.22±0.21)、(0.71±0.14)、(0.37±0.26),并在中、高剂量组引起了幼鼠突触相关蛋白Syn1和Spy的mRNA水平显著降低,分别由对照组的(1.10±0.09)、(0.97±0.08)下降到中剂量的(0.41±0.23)、(0.71±0.17)和高剂量的(0.39±0.19)、(0.63±0.19),差异均有统计学意义(P<0.05)。 结论 PFOS损伤海马BDNF/TrkB/CREB信号通路可能是PFOS神经发育毒性之一。     

c‐Src promotes tumor progression through downregulation of microRNA‐129‐1‐3p

MicroRNAs (miRNAs) fine‐tune cellular signaling by regulating expression of signaling proteins, and aberrant expression of miRNAs is observed in many cancers. The tyrosine kinase c‐Src is upregulated in various human cancers, but the molecular mechanisms underlying c‐Src‐mediated tumor progression remain unclear. In previous investigations of miRNA‐mediated control of c‐Src‐related oncogenic pathways, we identified miRNAs that were downregulated in association with c‐Src transformation and uncovered the signaling networks by predicting their target genes, which might act cooperatively to control tumor progression. Here, to further elucidate the process of cell transformation driven by c‐Src, we analyzed the expression profiles of miRNAs in a doxycycline‐inducible Src expression system. We found that miRNA (miR)‐129‐1‐3p was downregulated in the early phase of c‐Src‐induced cell transformation, and that reexpression of miR‐129‐1‐3p disrupted c‐Src‐induced cell transformation. In addition, miR‐129‐1‐3p downregulation was tightly associated with tumor progression in human colon cancer cells/tissues. Expression of miR‐129‐1‐3p in human colon cancer cells caused morphological changes and suppressed tumor growth, cell adhesion, and invasion. We also identified c‐Src and its critical substrate Fer, and c‐Yes, a member of the Src family of kinases, as novel targets of miR‐129‐1‐3p. Furthermore, we found that miR‐129‐1‐3p‐mediated regulation of c‐Src/Fer and c‐Yes is important for controlling cell adhesion and invasion. Downregulation of miR‐129‐1‐3p by early activation of c‐Src increases expression of these target genes and synergistically promotes c‐Src‐related oncogenic signaling. Thus, c‐Src‐miR‐129‐1‐3p circuits serve as critical triggers for tumor progression in many human cancers that harbor upregulation of c‐Src.