阿霉素联合顺铂诱导宫颈癌细胞凋亡实验研究

目的:研究化疗药物阿霉素(ADM)联合顺铂(DDP)对宫颈癌CaSki细胞株的增殖及凋亡的影响,并探讨其可能的相互作用机制。方法:应用MTT比色法检测不同浓度阿霉素、顺铂单独和联合应用对宫颈癌CaSki细胞的增殖抑制作用;同时RT-PCR法在mRNA水平上检测Bcl-2和TNF-α基因表达量的变化。结果:两种药物单独应用均可抑制CaSki细胞的增殖,联合用药(<12μg/mL)时具有协同抑制作用并与各药物单一应用比较具有显著性差异(P<0.05);阿霉素、顺铂作用CaSki细胞后能上调TNF-α基因和下调Bcl-2基因的表达。结论:宫颈癌CaSki细胞在化疗药物阿霉素和顺铂两药联合作用下通过诱导TNF-α和Bcl-2 mRNA表达量的变化发挥协同抑制作用,同时TNF-α的高表达增强了化疗药物阿霉素和顺铂诱导肿瘤细胞凋亡的敏感性,其机制主要与凋亡诱导效应有关。     

肿瘤血管导向性干扰素IFN-α2a-NGR与5-氟尿嘧啶联合应用对A549细胞增殖的影响

目的:观察重组蛋白肿瘤血管导向性干扰素IFN-α2a-NGR与化疗药物5-氟尿嘧啶联合使用在体外对人非小细胞肺癌细胞株A549的作用,为IFN-α2a-NGR的临床实验设计提供实验依据。方法:不同浓度的肿瘤血管导向性干扰素IFN-α2a-NGR、5-氟尿嘧啶单独及联合作用于细胞株A549,通过MTT法检测单药及联合用药对细胞增殖的影响,经AnnexinⅤ-FITC细胞凋亡检测试剂盒染色、流式细胞术检测细胞凋亡情况,荧光显微镜观察药物作用的细胞形态。结果:IFN-α2a-NGR与5-氟尿嘧啶联合作用于A549细胞株时,其细胞增殖抑制率、细胞凋亡率均较单独作用时高,具有统计学显著性差异(P<0.05);荧光显微镜观察可见药物作用后细胞形态改变。结论:肿瘤血管导向性干扰素IFN-α2a-NGR与5-氟尿嘧啶联合使用具有协同抑制肿瘤细胞增殖的作用。     

细胞因子和视黄酸调节肺癌细胞补体的生物合成

目的探讨近年用来治疗恶性肿瘤的视黄酸与细胞因子(TNF-α、IL-1β、IL-4、IL-6、IFN-γ)对人肺癌细胞株A549分泌C3及Β因子的影响。方法分别用ELISA、Western blot和RT-PCR检测培养上清中C3及B因子的水平及细胞C3及B因子mRNA表达。结果TNF-α、IL-1β、IL-4、IL-6和IFN-γ诱导A549细胞分泌C3及B因子是未处理组的6.84、11.0,7.27、8.04,6.16、1.08,4.75、1.43和2.10、1.59倍。视黄酸对Α549细胞分泌C3及B因子没有影响,但它能增强TNF-α、IL-1β、IL-4、IL-6和IFN-γ诱导的A549分泌C3及B因子分别是TNF-α、IL-1β、IL-4、IL-6和IFN-γ组的1.46、1.90,1.44、1.90,1.18、1.69,0.94、2.52,和1.09、2.39倍。RT-PCR半定量分析C3及B因子mRNA的结果与蛋白水平相似。结论视黄酸能调节诸细胞因子增强诱导人肺癌细胞株A549细胞分泌C3及B因子,这可提高细胞因子对肿瘤细胞的杀伤作用。     

白细胞介素18

白细胞介素-18(IL-18)是新发现的细胞因子,具有多种生物学功能.IL-18能促进外周血单个核细胞产生干扰素-γ(IFN-γ)、IL-2、粒细胞巨噬细胞集落刺激因子(GM-CSF)等细胞因子,增强天然杀伤细胞(NK细胞)的细胞毒作用.IL-18结构上与IL-1相似,而功能更接近IL-12,IL-18与IL-12均能诱导Th1细胞产生IFN-γ,存在协同效应,但它们的作用途径不同.IL-18在抗感染抗肿瘤等方面有着潜在的应用前景,并与自身免疫性疾病的发病密切相关.     

IL-1α、IFN-γ、TNF-α和NGF-β在胚胎后期皖西白鹅中脑的表达

用免疫组化SABC法研究白介素-1α(IL-1α)、干扰素-γ(IFN-γ)、肿瘤坏死因子-α(TNF-α)和神经生长因子-β(NGF-β)在胚胎后期皖西白鹅中脑的表达与分布,并作统计学处理。结果发现,中央灰质层、中央白质层、室周灰质纤维层、半圆丘、峡核细胞胞质与突起阳性反应明显,其中峡核阳性反应最为明显,顶盖最不明显,且峡核大细胞部纤维着色明显;IL-1α在4种细胞因子中分布范围最广,阳性反应最强;IFN-γ与TNF-α阳性反应中,部分树突着色明显,且IFN-γ染色效果强于TNF-α;NGF-β的阳性突起与纤维较少。由结果可得,细胞因子可能是通过峡核-顶盖通路的作用,由峡核传递到顶盖;IL-1α在中枢神经系统中有重要作用;IFN-γ作为中枢神经系统介质的作用强于TNF-α。     

卡介苗作用大鼠膀胱肿瘤细胞／正常移行上皮细胞后TNF—α．、IL-10、IFN-γ的检测及意义

目的：观察卡介苗（BCG）单独作用膀胱肿瘤细胞、正常膀胱移行上皮细胞及其代谢产物作用上述细胞后细胞生长情况及各自细胞培养液上清液中细胞因子（TNF-α．、IL-10、IFN-γ）浓度的变化,探讨其在卡介苗治疗膀胱肿瘤中可能的作用机制。方法：构建大鼠膀胱肿瘤模型,并原代培养大鼠膀胱肿瘤细胞及正常膀胱移行上皮细胞。分别用BCG,普通培养液和细胞培养的代谢产物作用上述细胞。酶联接免疫吸附剂测定法（ELISA法）检测各组细胞上清液中肿瘤坏死因子-α（TNF-α）、白细胞介素-10（IL-10）、干扰素-γ（IFN-γ）的浓度。结果：ELISA法检测各组细胞上清液中TNF-α、IL-10的浓度改变有显著差异,而IFN-γ的浓度无显著差异。结论：BCG可以直接刺激肿瘤细胞自身分泌细胞因子（TNF-α、IL-10）参与调节抑制肿瘤细胞的生长。     

大黄素对顺铂耐药卵巢癌细胞的逆转作用及其相关基因表达研究

为了研究大黄素对人卵巢癌耐药细胞株SKOV3/DDP细胞耐药逆转作用及其机制,本研究以卵巢癌SK-OV3和多药耐药细胞株SKOV3/DDP为研究对象,通过噻唑蓝(MTT)法测定SKOV3/DDP细胞的耐药指数和大黄素在无细胞毒浓度下对卵巢癌细胞耐受顺铂(DDP)的逆转作用;采用Real-time PCR技术检测耐药相关基因HIF-1α、STAT1、CK2α、GSTP1 mRNA表达情况。结果发现无细胞毒作用浓度的7.8 mg/L和3.9 mg/L大黄素能逆转SKOV3/DDP细胞对DDP的耐药性,对DDP的逆转倍数分别为1.91倍和1.30倍,与SKOV3比较,SKOV3/DDP细胞的HIF-1α、STAT1、CK2α、GSTP1 mRNA表达明显升高(P<0.01)。3.9 mg/L和7.8 mg/L大黄素作用均可下调HIF-1α、CK2α、STAT1 mRNA表达,存在剂量-效应依赖关系。7.8 mg/L大黄素作用可下调GSTP1 mR-NA表达,但3.9 mg/L大黄素作用不明显。7.8 mg/L和3.9 mg/L大黄素联合IC50浓度的DDP时,四个耐药相关基因的表达与单独化疗药组作用相比明显下调(P<0.01)。提示无细胞毒浓度的大黄素对卵巢癌细胞耐药逆转的作用可能是通过下调HIF-1α、STAT1、GSTP1、CK2α的表达起作用。     

细胞因子诱导杀伤细胞过继免疫治疗恶性血液肿瘤的临床应用进展

细胞因子诱导的杀伤细胞(cytokine-induced killer cells,CIK cells)是将脐血、外周血和骨髓等不同来源的单个核细胞经适当浓度的IFN-γ、IL-2和CD3单抗等联合诱导后获得的异质细胞群。CIK细胞具有增殖能力强、溶瘤谱广、对耐药细胞株也有杀伤作用,且兼有T细胞强大的杀伤活性和NK细胞(nature killer cells)非主要组织相容性复合体(non-major histocompatibility complex,non-MHC)限制性的特点,使其在肿瘤治疗中具有广阔的临床应用前景。恶性血液肿瘤患者接受CIK细胞过继免疫治疗的生存时间延长,不良反应少,但仍面临许多问题。     

黄芪多糖对Lewis肺癌小鼠细胞因子及顺铂所致免疫功能低下的影响

目的观察黄芪多糖(APS)对小鼠Lewis肺癌移植瘤生长、细胞因子及顺铂(DDP)所致免疫功能低下的影响。方法 90只小鼠,设空白对照组10只,余80只依次造模为荷瘤小鼠,并随机分为8组:模型组(等体积生理盐水),顺铂阳性对照组(6 mg/kg DDP),APS低(50 mg/kg)、中(100 mg/kg)、高剂量(200 mg/kg)组,联合用药低、中、高剂量组(DDP剂量减半,APS各剂量同上),于造模次日起各组分别腹腔注射等体积的药物0.3 mL。DDP每周一次,其余药物每天1次,连续20d。于第21天取血清采用ELISA法测定细胞因子IL-2、IL-6、IL-12、TNF-α的水平,并观察各组抑瘤率及免疫器官指数。结果 DDP、APS低、中、高剂量及联合用药低、中、高剂量组对小鼠Lewis肺癌移植瘤的抑瘤率分别为49.30%、17.21%、39.68%、42.98%、51.02%、57.21%、65.11%(与模型组比较P0.05或0.01;联合用药组与DDP组比较P0.05)。与空白对照组比较,APS中、高剂量组和联合用药组脾脏指数显著升高;与模型组比较,APS高剂量和联合高剂量脾脏指数差异有显著性(P0.05);与DDP组比较,APS各剂量和联合用药组小鼠胸腺指数和脾脏指数均升高。结论 APS能提高Lewis肺癌小鼠血清中细胞因子IL-2、IL-6、IL-12、TNF-α的水平;增强DDP所致免疫功能低下小鼠的免疫功能,对免疫器官有一定的保护作用;能抑制小鼠Lewis肺癌细胞的生长,在与DDP减半量联合使用时可使DDP抑瘤作用增强,且其机制可能与增强机体的免疫功能有关,说明APS对DDP有一定的增效减毒作用。此项研究在实体瘤的治疗中有潜在的应用前景。     

CpG-ODN2216致敏的单核细胞培养上清对HBV相关性肝癌病人的树突状细胞表型和功能的影响

目的:研究CpG-ODN2216致敏的外周血单核细胞(PBMC)培养上清液对HBV相关性肝癌病人的树突状细胞(DC)成熟与功能的影响,寻求一种增强DC疫苗效果的方法。方法:从9例HBV相关性肝癌患者PBMC中诱导出未成熟的单核细胞来源的DC(MoDC),经HBV核心抗原(HBcAg)负载后,用CpG-ODN2216刺激的PBMC上清液、“细胞因子鸡尾酒(IL-1β、IL-6、TNF-α和PGE2)”以及两者的联合作用促进MoDC的进一步成熟,检测MoDC表型和功能;选择其中5例HLA-A2 病人,用成熟MoDC诱导自身T细胞产生HBV特异性CD8 的细胞毒性T淋巴细胞(CTL)。结果:用细胞因子鸡尾酒和CpG-ODN2216刺激的PBMC上清液联合作用可明显增强MoDC表面的CD80、CD83和CD1a表达,其对HBcAg负载的MoDC促成熟作用大于单独用细胞因子鸡尾酒或单独用CpG-ODN2216刺激PBMC的上清液。联合作用促进MoDC分泌IL-12和IL-10的能力明显强于单独应用PBMC上清液或细胞因子鸡尾酒,其刺激自体T细胞分泌IFN-γ、TNF-α、IL-6的能力也明显增高。联合作用促成熟的MoDC诱导HLA-A2 病人的自体T细胞产生HBVcore18-27特异性CD8 CTL的频率明显高于细胞因子鸡尾酒单独促成熟的MoDC。结论:CpG-ODN2216刺激PBMC的上清液和细胞因子鸡尾酒联合作用可以明显促进HBcAg负载的HBV相关性肝癌病人的MoDC成熟,增强MoDC分泌细胞因子、刺激自体特异性T淋巴细胞应答、诱导HBV特异性细胞毒性T细胞的能力。为提高HBV特异性树突状细胞疫苗的效果提供了一种可行方案。     

Coupling the cell cycle to cell growth

In order to multiply, both prokaryotic and eukaryotic cells go through a series of events that are collectively called the cell cycle. However, DNA replication, mitosis and cell division may also be viewed as having their own, in principle independent, cycles, which are tied together by mechanisms extrinsic to the cell cycle—the checkpoints—that maintain the order of events. We propose that our understanding of cell-cycle regulation is enhanced by viewing each event individually, as an independently regulated process. The nature of the parameters that regulate cell-cycle events is discussed and, in particular, we argue that cell mass is not such a parameter.     

Navigating the cell

Changes in cell shape are associated with a variety of processes including cell migration, axon outgrowth, cell division, and vesicle trafficking. C. elegans UNC-53 and its vertebrate homologs, the Navigators, are required for the migration of cells and the outgrowth of neuronal processes. The identification of novel molecular interactions and live imaging studies have revealed that UNC-53/NAVs are signal transducers associated with actin filaments, microtubules, and intermediate filaments. In addition to modulating cytoskeletal dynamics at the leading edge of migrating or outgrowing cells, both UNC-53 and the navigators are expressed in adult cells, conspicuously those with specialized roles in endocytosis or secretion. Collectively, these results suggest that UNC-53/NAVs may be a central regulator of cytoskeletal dynamics, responsible for integrating signaling cues to multiple components of the cytoskeleton to coordinate rearrangement during cell outgrowth or trafficking.     

A unique cell type in the lung--the Clara cell (the non-ciliated bronchiolar epithelial cell)

The non-ciliated bronchiolar epithelial cells (the Clara cells) are found most frequently in the distal conducting airways, but they are found throughout the tracheobronchial tree of different mammalian species. According to recent data, the main functions of the Clara cells can summarized as (1), the secretion of certain components of the extracellular bronchiolar lining layer (2), metabolism and detoxification of xenobiotics and other toxic compound (3) and participation in the renewal process of the bronchiolar epithelium. The main goal of this paper is to collect and discuss some of the general features of Clara cells from a functional-morphological point of view, and their possible role in pathological alterations of the lung especially in the pathogenesis of lung tumours originated from Clara cells.     

Mechanotransduction and endothelial cell homeostasis: the wisdom of the cell

Vascular endothelial cells (ECs) play significant roles in regulating circulatory functions. Mechanical stimuli, including the stretch and shear stress resulting from circulatory pressure and flow, modulate EC functions by activating mechanosensors, signaling pathways, and gene and protein expressions. Mechanical forces with a clear direction (e.g., the pulsatile shear stress and the uniaxial circumferential stretch existing in the straight part of the arterial tree) cause only transient molecular signaling of pro-inflammatory and proliferative pathways, which become downregulated when such directed mechanical forces are sustained. In contrast, mechanical forces without a definitive direction (e.g., disturbed flow and relatively undirected stretch seen at branch points and other regions of complex geometry) cause sustained molecular signaling of pro-inflammatory and proliferative pathways. The EC responses to directed mechanical stimuli involve the remodeling of EC structure to minimize alterations in intracellular stress/strain and elicit adaptive changes in EC signaling in the face of sustained stimuli; these cellular events constitute a feedback control mechanism to maintain vascular homeostasis and are atheroprotective. Such a feedback mechanism does not operate effectively in regions of complex geometry, where the mechanical stimuli do not have clear directions, thus placing these areas at risk for atherogenesis. The mechanotransduction-induced EC adaptive processes in the straight part of the aorta represent a case of the "Wisdom of the Cell," as a part of the more general concept of the "Wisdom of the Body" promulgated by Cannon, to maintain cellular homeostasis in the face of external perturbations.     

Role of the cell surface in the stimulation of cell multiplication

Fertilization of eggs and effects of many growth factors on the membrane receptors of the cultured somatic cells induce similar changes in the plasma membrane transport properties, which determine changes in Ca2+ and H+ concentrations in the cytoplasm. The data are discussed which favour the concept that Ca2+ and H+ are secondary messengers of growth-stimulating influences and control many intracellular processes related to cell multiplication.