Galectin-9 as a regulator of cellular adhesion in human oral squamous cell carcinoma cell lines

Oral squamous cell carcinomas (OSCCs), a major public health problem worldwide, are the most common neoplasms of the head and neck. The most important prognostic indicator for patients with OSCC is metastasis to cervical lymph nodes or distant organs. Galectin-9 is correlated with cellular adhesion and aggregation in melanoma cells. To investigate expression levels of galectin-9 mRNA and protein, we performed qRT-PCR and Western blot analyses on OSCC cell lines (Ca9-22, HSC-2, and HSC-3) and normal oral keratinocytes (NOKs). Galectin-9 mRNA and protein were commonly down-regulated in OSCC cell lines compared with NOKs. We further analyzed Ca9-22, which had the lowest expression of galectin-9. We then transfected the galectin-9 cDNA into Ca9-22 cells to examine whether overexpression of galectin-9 increases cellular adhesion in vitro. An adhesion assay using a fibronectin and collagen I coating plate revealed an increased cellular adherence ratio in overexpressed galectin-9 cells compared with nontransfected cells (p < 0.05). The data suggest that galectin-9 is correlated with oral cancer cell-matrix interactions and may therefore play an important role in the metastasis of OSCCs.     

DEC1 (STRA13) protein expression relates to hypoxia- inducible factor 1-alpha and carbonic anhydrase-9 overexpression in non-small cell lung cancer

Differentiated embryo-chondrocyte expressed gene 1 (DEC1) is involved in cell differentiation, proliferation, and apoptosis, and was recently shown to be regulated by hypoxia. The present immunohistochemical study demonstrates extensive nuclear expression of the protein in 38% of a series of 115 non-small cell lung carcinomas using a polyclonal antibody (Ab) recognizing DEC1 protein. Such expression was directly related to the expression of two hypoxia-regulated proteins, namely the hypoxia-inducible factor (HIF) 1alpha and carbonic anhydrase-9. Although DEC1 was not related to angiogenesis or to the expression of VEGF and thymidine phosphorylase, a direct association with up-regulated bFGF receptors was noted. DEC1 was persistently expressed in the nuclei of normal bronchial and alveolar tissue. It is suggested that loss of DEC1 expression is an early event in the development of lung cancer, while DEC1 gene expression occurs in a subset of tumours and parallels the overexpression of other hypoxia-regulated proteins.     

Caspase-1 activity as a possible predictor of apoptosis induced by cisplatin in gastric cancer cells

Recent studies have shown that caspases, which are cystein proteases, elevate endonuclease activity and induce apoptosis. Caspase-1, an interleukin-1beta converting enzyme, has been reported to be related with anti-cancer drug induced apoptosis as well as with caspase-3. To elucidate the caspase-1 activity, which might be a predictor for the effect of chemotherapy, we examined the changes of caspase-1 activity induced after exposure to cisplatin (CDDP) in six gastric cancer cell lines. A high correlation between the 50% inhibitory concentration (IC50) and caspase-1 activity ratio was shown (r=0.83, p=0.041) (caspase-1 activity ratio: the caspase-1 activity of cells at 4 h after CDDP treatment/the caspase-1 activity of untreated cells). Further, we examined the correlation between caspase-1 activity and apoptosis induced by CDDP in two cell lines that have very different CDDP sensitivities; OCUM-2M and OCUM-2M/DDP (IC50; 0. 85+/-0.4 microg/ml and 9.0+/-1.2 microg/ml, respectively). The apoptotic index of OCUM-2M was significantly higher than that of OCUM-2M/DDP (19.8+/-3.8% vs. 4.5+/-1.2%, respectively; p=0.0005). In both cell lines, caspase-1 activity began to increase immediately after exposure to CDDP and peaked at approximately 4 h after cessation of exposure to CDDP, and gradually decreased thereafter. The caspase-1 activity of OCUM-2M was approximately 1.8-times higher than that of OCUM-2M/DDP at 4 h after exposure to CDDP. Taken together, our results indicate that evaluating the changes of caspase-1 activity after exposure to CDDP may be useful to predict apoptosis following CDDP treatment in gastric cancer cells.     

过表达脑红蛋白抑制双转基因AD小鼠脑中Aβ诱导的凋亡

目的:研究AD双转基因(APPswe/PS1d E9)小鼠侧脑室注射质粒p NGB后,过表达脑红蛋白(neuroglobin,NGB)对Aβ诱导的AD小鼠脑中细胞凋亡的影响及其潜在机制。方法:将24只鉴定后的13月龄AD双转基因阳性小鼠(雌雄各半)随机分为对照组、侧脑室注射生理盐水+pc DNA3.1(1 g/L)组和侧脑室注射pc DNA3.1(1 g/L)+p NGB组。采用免疫组化检测鼠脑Aβ1-42表达情况,TUNEL染色检测脑内细胞的凋亡情况;Western blot检测鼠脑内与凋亡密切相关的cleaved caspase-3、caspase-9以及PI3K、p-Akt、Akt的蛋白水平。结果:与对照组和注射生理盐水组比较,注射p NGB组小鼠脑内Aβ1-42的表达明显受到抑制(P0.01),TUNEL染色阳性细胞数也明显减少(P0.01);过表达NGB能够明显抑制脑组织内cleaved caspase-3和caspase-9的蛋白表达(P0.01),促进Akt磷酸化水平的增强(P0.01)。结论:p NGB过表达能够明显抑制Aβ的生成并抑制Aβ诱导的细胞凋亡,其机制可能与激活PI3K/Akt通路进而抑制与凋亡密切相关的cleaved caspase-3和caspase-9的表达有关。     

p53依赖的X-连锁凋亡抑制蛋白调节与卵巢癌顺铂耐药的关系

目的本研究旨在探讨X-连锁凋亡抑制蛋白（XIAP）在卵巢癌顺铂耐药中的作用。方法应用RT—PCR、Western Blot、流式细胞仪等检测卵巢癌顺铂敏感细胞株0V2008、A2780s和耐药株C13＊、A2780cp中XIAP表达和卵巢癌细胞的凋亡率,并将反义XIAP寡核苷酸（XIAPAs—ODN）、正义XIAP寡核苷酸（XIAPs—ODN）和随机对照链导入顺铂耐药细胞C13＊（p53野生型）和A2780cp（p53突变型）中,比较转染前、后耐药细胞Caspase-3活性和顺铂耐药性的改变。结果卵巢癌顺铂敏感细胞和耐药细胞中XIAP在mRNA水平的表达无明显差异（P〉0．05）。顺铂可以引起OV2008和A2780s中XIAP蛋白表达明显下降（P〈0．05）,而对C13＊和A2780cp的XIAP蛋白含量无明显影响（P〉0．05）。转染XIAPAs—ODN可降调p53野生型耐药细胞C13＊中XIAP的表达,并显著增加Caspase-3活性和对顺铂敏感性（P〈0．05）,而XIAP As—ODN对p53突变型耐药细胞A2780cp无此作用。结论卵巢癌细胞对顺铂产生耐药可能与XIAP蛋白相对高表达有关,反义XIAP可在一定程度上逆转卵巢癌顺铂耐药,该作用与卵巢癌细胞的p53表型有关。     

DEC1基因过表达对人食管癌ECA109细胞增殖及侵袭能力的影响

目的:探讨DEC1基因过表达对人食管癌ECA109细胞增殖和侵袭能力的影响及可能机制。方法:将质粒pc DNA3.1(-)/DEC1(DEC1组)和pc DNA3.1(-)(vector组)利用脂质体分别转染至人食管癌ECA109细胞中,通过real-time PCR检测转染48 h后的细胞内DEC1 mRNA表达,Western blot分别检测转染72 h后细胞内DEC1、基质金属蛋白酶9(MMP9)及细胞周期蛋白cyclin D1的蛋白表达;采用CCK-8实验、平板集落实验及Transwell实验分别检测DEC1过表达对细胞的增殖和侵袭能力的影响。结果:与vector组相比,DEC1组中DEC1的表达明显增高(P0.01);cyclin D1和MMP9的表达明显降低(P0.05);细胞增殖与侵袭能力明显受到抑制(P0.01)。结论:过表达DEC1可明显抑制ECA109细胞的增殖和侵袭能力,DEC1可能通过影响MMP9和cyclin D1参与其中。     

转录因子ZFP580在缺氧预处理抗大鼠心肌细胞缺氧/复氧损伤中的作用

 目的：通过观察缺氧预处理对心肌细胞缺氧/复氧损伤的保护作用及锌指核转录因子ZFP580表达的改变,探讨ZFP580的作用及机制。方法：培养大鼠H9c2心肌细胞,分为3组：（1） 缺氧/复氧(H/R)组：H9c2心肌细胞换用模拟缺血溶液(pH=6.2)缺氧(95% N2 + 5% CO2)培养3 h,复氧培养2 h;（2） 缺氧预适应(HPC)组：H9c2心肌细胞经3个循环的短暂缺氧(10 min)/复氧(20 min)处理后,进行同上H/R实验;(3) 对照(C)组：正常培养的H9c2心肌细胞。通过MTT染色及LDH水平判定HPC的作用。Western blotting方法观察心肌细胞中转录因子ZFP580表达及ERK1/2磷酸化情况,以及ERK1/2磷酸化抑制剂PD98059对ZFP580表达的影响。分别构建高/低表达ZFP580的慢病毒载体并转染H9c2心肌细胞,经H/R实验后利用Annexin V-PE/7-AAD染色及流式细胞术检测H9c2细胞凋亡情况,Western bloting方法观察caspase-3活化情况。结果：HPC能显著改善H/R处理后H9c2心肌细胞存活率降低和LDH漏出的现象。Western blotting结果显示,HPC组心肌细胞中ZFP580表达及ERK1/2磷酸化程度较H/R处理组明显上升,且PD98059预处理明显抑制HPC诱导的ZFP580的表达上调。慢病毒介导的基因转染实验发现,ZFP580高表达的H9c2心肌细胞在H/R损伤后凋亡率降低且细胞中活化caspase-3表达下降。结论：HPC可引起心肌细胞中转录因子ZFP580表达上调,ZFP580作为ERK1/2通路的下游靶分子发挥抗心肌细胞凋亡的作用。ZFP580表达上调可能作为内源性保护机制之一介导了HPC的细胞保护作用。     

PER2对人口腔鳞癌SCC15细胞增殖、凋亡以及生物钟基因表达的影响

目的探讨人口腔鳞癌SCC15细胞中生物钟基因PER2的表达改变对细胞增殖、凋亡以及其他生物钟基因的影响。方法用RNA干扰技术沉默人口腔鳞癌SCC15细胞中PER2基因;流式细胞术检测细胞增殖和凋亡水平;实时荧光定量PCR检测生物钟基因CLOCK、BMAL1、PER1、PER3、DEC1、DEC2、CRY1、CRY2、TIM、CKIε、RORα、NPAS2和REV-ERBαmRNA表达。结果沉默PER2后,SCC15细胞的增殖水平显著增加,凋亡显著下降(P0.05);SCC15细胞中生物钟基因PER3、BMAL1、DEC1、DEC2、CRY2、TIM、RORα和NPAS2 mRNA的表达水平显著降低,PER1和REV-ERBαmRNA的表达显著升高(P0.05)。结论在癌细胞中,生物钟基因PER2对生物钟基因网络中其他生物钟基因具有重要调控作用,PER2表达降低导致细胞增殖增加和细胞凋亡水平下降。     

Calcineurin inhibitor‐induced complement system activation via ERK1/2 signalling is inhibited by SOCS‐3 in human renal tubule cells

One factor that significantly contributes to renal allograft loss is chronic calcineurin inhibitor (CNI) nephrotoxicity (CIN). Among other factors, the complement (C‐) system has been proposed to be involved CIN development. Hence, we investigated the impact of CNIs on intracellular signalling and the effects on the C‐system in human renal tubule cells. In a qPCR array, CNI treatment upregulated C‐factors and downregulated SOCS‐3 and the complement inhibitors CD46 and CD55. Additionally, ERK1/‐2 was required for these regulations. Following knock‐down and overexpression of SOCS‐3, we found that SOCS‐3 inhibits ERK1/‐2 signalling. Finally, we assessed terminal complement complex formation, cell viability and apoptosis. Terminal complement complex formation was induced by CNIs. Cell viability was significantly decreased, whereas apoptosis was increased. Both effects were reversed under complement component‐depleted conditions. In vivo, increased ERK1/‐2 phosphorylation and SOCS‐3 downregulation were observed at the time of transplantation in renal allograft patients who developed a progressive decline of renal function in the follow‐up compared to stable patients. The progressive cohort also had lower total C3 levels, suggesting higher complement activity at baseline. In conclusion, our data suggest that SOCS‐3 inhibits CNI‐induced ERK1/‐2 signalling, thereby blunting the negative control of C‐system activation.     

DDAH2抑制低氧诱导大鼠心肌细胞H9c2(2-1)凋亡

 目的 探讨过表达二甲基精氨酸二甲胺水解酶-Ⅱ（DDAH2）对低氧诱导的大鼠心肌细胞凋亡的抑制作用和是否通过内皮型一氧化氮合酶（eNOS）活化来保护心肌细胞。方法 低氧诱导大鼠心肌细胞H9c2(2-1)36h从而诱导凋亡,同时转染DDAH2真核细胞表达质粒,用WST-1细胞毒试验和流式细胞术检测细胞凋亡,Western blot法检测eNOS磷酸化。结果 低氧组心肌细胞存活率显著性降低;过表达DDAH2基因使低氧下心肌细胞存活率明显地上升。DDAH2过表达组心肌细胞凋亡率为17.38%±1.52%,显著性低于低氧组（27.34%±1.33%）（P<0.05）。转染DDAH2基因可以显著上调低氧组心肌细胞的eNOS磷酸化水平;过表达DDAH2基因的低氧组用eNOS抑制剂L-NAME干预后,凋亡水平明显上升。结论 过表达DDAH2基因上调eNOS磷酸化抑制低氧所致的大鼠心肌细胞H9c2（2-1）凋亡。     

TREM-1 promoted apoptosis and inhibited autophagy in LPS-treated HK-2 cells through the NF-κB pathway

Triggering receptor expressed by myeloid cells (TREM-1) is an amplifier of inflammatory responses triggered by bacterial or fungal infection. Soluble TREM-1 (sTREM-1) expression was found to be upregulated in sepsis-associated acute kidney injury (SA-AKI) and predicted to be a potential biomarker. However, the mechanism remains unclear. The human kidney-2 (HK-2) cell line was treated with lipopolysaccharide (LPS) and used to examine the potential roles of TREM-1 in apoptosis and autophagy. A cell viability assay was employed to assess the number of viable cells and as a measure of the proliferative index. The concentrations of sTREM-1, interleukin (IL)-1β, tumor necrosis factor-α (TNFα) and IL-6 in cell-free culture supernatants were measured by enzyme-linked immunosorbent assay (ELISA). Western blot analysis was performed to analyze apoptosis, autophagy and the relevant signaling pathways. The results suggested that TREM-1 overexpression after LPS treatment decreased proliferation and increased apoptosis. The concentrations of sTREM-1, IL-1β, TNFα and IL-6 in cell-free culture supernatants were increased in the TREM-1 overexpression group after LPS treatment. Expression of the antiapoptotic gene Bcl-2 was downregulated in the TREM-1 overexpression group, while that of the proapoptotic genes Bax, cleaved caspase-3 and cleaved caspase-9 was upregulated. Overexpression of TREM-1 downregulated expression of the autophagy genes Beclin-1, Atg-5 and LC3b and increased the gene expression of p62, which inhibits autophagy. Conversely, treatment with TREM-1-specific shRNA had the opposite effects. The nuclear factor-κB (NF-κB) signaling pathway (P-p65/p65 and P-IκBα/IκBα) in LPS-induced HK-2 cells was regulated by TREM-1. In summary, TREM-1 promoted apoptosis and inhibited autophagy in HK-2 cells in the context of LPS exposure potentially through the NF-κB pathway.     

TIPE2 抑制AP-1 蛋白增加人非小细胞肺癌细胞系NCI-H1975 化疗敏感性的机制研究

目的:探讨TIPE2 增强非小细胞肺癌细胞系NCl-H1975 化疗敏感性及其机制。方法:非小细胞肺癌系NCI-H1975 转入TIPE2 慢病毒载体后,加入CDDP 后使用CCK-8 测量IC50 值,凋亡细胞用AnnexinV/ FITC 和PI 凋亡检测试剂盒进行检测,Western blot 检测转染TIPE2 后AP-1 及MDR-1 的蛋白表达量,实时荧光定量PCR 检测转染TIPE2 后IL-1、IL-6 及TNF-αmRNA 水平。结果:(1)TIPE2 降低非小细胞肺癌系NCI-H1975 细胞IC50 值(P<0.001);(2)TIPE2 增加非小细胞肺癌系NCI-H1975 细胞对CDDP 的凋亡率(P<0.05);(3) TIPE2 可显著降低非小细胞肺癌系NCI-H1975 细胞中AP-1 及MDR1 的表达量;(4)TIPE2 可显著降低非小细胞肺癌系NCI-H1975 细胞中IL-1、IL-6 及TNF-αmRNA 水平的表达(P<0.01)。结论:TIPE2 可能通过抑制AP-1 蛋白增加非小细胞肺癌细胞系NCl-H1975 对CDDP 的化疗敏感性。     

DJ-1可通过增强自噬水平缓解鱼藤酮致MN9D细胞损伤

 目的 探讨DJ-1对MN9D细胞的保护作用及具体机制。方法 在MN9D细胞中瞬时转染DJ-1质粒,利用MTT法及流式细胞术分别检测MN9D细胞活力与凋亡水平。通过激光共聚焦显微镜(confocal)观察LC3自噬点数量。利用Western blot法检测LC3II/LC3I的比值。结果 过表达DJ-1能部分恢复鱼藤酮引起的细胞活力下降(P<0.05)且可以减少鱼藤酮引起的MN9D细胞凋亡(P<0.05)。过表达DJ-1增加了鱼藤酮处理的MN9D细胞内荧光点的数量(P<0.001)且使LC3Ⅱ/Ⅰ的比值增高显著(P<0.001),应用3-MA干预后,细胞内荧光点数量回落到基础水平,且LC3Ⅱ/Ⅰ的比值明显降低(P<0.05)。同时应用自噬抑制剂3-MA干预后,DJ-1的细胞保护作用消失。结论 DJ-1通过激活自噬,起保护作用能减轻鱼藤酮引起的毒性。