Carnosic acid exhibits antiproliferative and proapoptotic effects in tumoral NCI-H460 and nontumoral IMR-90 lung cells

ABSTRACT

Carnosic acid (CA) is a phenolic diterpene with many important biological activities including antimicrobial, antioxidant, anti-inflammatory properties, and anti-proliferative properties. The aim of the present study was to investigate cytotoxic activity, cell cycle, apoptotic, and molecular effects attributed to CA in non-tumoral IMR-90 (human fetal lung fibroblasts), as well as tumoral NCI-H460 (human non–small-cell lung cancer) cell lines. Cell proliferation was evaluated by Real-Time Cell Analysis system, while apoptosis and cell cycle were assessed using flow cytometry. RT-qPCR was used to estimate the relative expression of genes involved in cell cycle regulation, DNA damage and repair, and apoptosis induction. CA inhibited proliferation of IMR-90 and NCI-H460 cells via cell cycle arrest at G₀/G₁ and G₂/M phases, according to the treatment concentration. The mRNA levels of genes encoding cyclins A2, B1, and B2 were downregulated in response to CA treatment of IMR-90 cells. Apoptosis was induced and proapoptotic gene PUMA was upregulated in both cell lines. mRNA levels of genes ATR, CCND1, CHK1, CHK2, MYC, GADD45A, H2AFX, MTOR, TP53, and BCL2, CASP3 were not markedly changed following CA treatments. Although CA exerted antiproliferative activity against NCI-H460 tumor cells, this phytochemical induced toxic effects in non-tumoral cells, and thus needs to be considered carefully prior to pharmacological use therapeutically.     

术前检测Cyclin A、E阳性细胞指导胃癌淋巴结清扫术

目的　探讨以细胞周期蛋白A、E (CyclinA、E)阳性细胞比例 (PCP)术前判断和术中指导胃癌淋巴结清扫范围的可行性。方法　 2 9例行“胃癌根治切除术 (D3 )”患者 ,术前自胃镜取病灶活检组织 ,术后自标本获取正常胃粘膜、原发癌肿及淋巴结组织进行CyclinA、E阳性细胞流式细胞仪检测。无或仅有Ⅰ站淋巴结转移者为实验A组 ,有Ⅱ站或 (和 )Ⅲ站淋巴结转移者为B组。结果　① 2 7例术前与术后获得的原发癌灶组织中CyclinA、E的PCP基本一致。其中实验A组 10例 ,B组 17例。②原发癌灶CyclinE的PCP大于 2 0 0 %者 ,A组为 2 0 0 % (2 / 10 ) ,B组为 76 5 % (13/ 17) ,两组间差异有显著性意义 (P <0 0 5 )。转移淋巴结的CyclinE明显高于对照组 ;CyclinA的PCP增高改变主要发生于原发癌灶。结论　CyclinE与胃癌进展和淋巴结转移明显相关 ;术前检测病灶活检组织中的CyclinE阳性细胞比例 ,可作为判断淋巴结转移状态的生物学指标 ,指导术中淋巴结清扫范围。     

过量胸苷对细胞周期素表达的影响

目的 :探讨过量胸苷干扰细胞周期素细胞周期时相表达的特点 ,为进一步研究细胞周期转化以及细胞周期素与DNA合成的关系奠定基础 .方法 :应用二次过量胸苷阻断法进行新生猪肾小管上皮细胞体外同步化培养 ,采用流式细胞术进行鉴定 ;然后分别进行G1/S,S及G2 期细胞CyclinA ,B ,D1mAb免疫细胞化学染色并进行图像分析 .结果 :二次过量胸苷阻断法可获取G1/S界面细胞为 (99 5± 0 8) % ,S期细胞为(90 5± 0 7) % ,G2 期细胞为 (93 5± 2 2 ) % ,G2 /G1=2 2 0 .G1/S ,S,G2 细胞CyclinA表达特点为G2 期大于G1/S和S期 (目标灰度值 :13 6 3± 2 7,14 5 0± 1 4 ,14 7 5± 1 8,P <0 0 1) ,CyclinB表达特点为G1/S期小于S和G2 期 (目标灰度值 :15 5 6± 1 6,14 8 8± 2 2 ,13 6 6± 2 6,P <0 0 1) ,CyclinD1的表达特点为G2期大于G1/S期 (目标灰度值 :13 2 .6± 1.9,14 6.7± 1.3 ,P <0 .0 1) ,S期小于G1/S期 (目标灰度值 :15 8 8± 1 1,14 6 7± 1 3 ,P<0 0 5 ) .结论 :二次过量胸苷阻断细胞DNA合成可能与细胞周期素表达的改变相关     

亚硒酸钠诱导结直肠癌SW480细胞系凋亡

目的探讨亚硒酸钠诱导结直肠癌SW480细胞凋亡的信号通路。方法将SW480细胞分为三组,分别进行亚硒酸钠、Mn TMPy P以及两者联用处理;用DCFH-DA荧光探针法检测细胞内活性氧;Western blot方法检测细胞信号通路JNK和ATF-2的磷酸化,以及c-Myc、c-Jun、c-Fos、cyclin D1、cyclin A2、Bcl-2等相关蛋白表达;流式细胞术检测SW480细胞凋亡率。结果亚硒酸钠可使SW480细胞产生活性氧;抑制JNK和ATF-2的磷酸化(P0.05),下调c-Myc、c-Jun、c-Fos、cyclin D1、cyclin A2、Bcl-2的表达诱导SW480细胞凋亡(P0.05);用活性氧抑制剂Mn TMPy P可减轻亚硒酸钠所致的上述变化(P0.05)。结论亚硒酸钠可通过产生活性氧,抑制JNK和ATF-2的磷酸化,下调c-Myc、c-Jun、c-Fos、cyclin D1、cyclin A2、Bcl-2的表达,促进SW480细胞的凋亡。     

乳鼠心肌组织中细胞周期素A2的定位及表达

背景：细胞周期素A2是调节细胞周期的关键因子,关于细胞周期素A2在乳鼠心肌中的表达及定位情况还不明确。 目的：探索细胞周期素A2在C57乳鼠中的表达定位及表达,检测心肌细胞中增殖相关蛋白随着细胞周期素A2的表达而呈现的表达趋势。 方法：C57乳鼠分别于出生后0,3,7,14,28 d处死,留取心肌组织,行Western blot检测心肌组织中细胞周期素A2、增殖细胞核抗原及磷酸组蛋白H3的表达情况。免疫组化检测细胞周期素A2在出生后乳鼠中的定位及增殖细胞核抗原在心肌组织中的表达。 结果与结论：C57乳鼠出生后细胞周期素A2表达水平逐渐下调,直至第14天基本消失(P=0.001),且细胞周期素A2在乳鼠出生后0 d定位于细胞核中,在第14天时主要存在于细胞质中,至第28天时,基本消失。增殖细胞核抗原在出生后0 d表达最强,随后表达逐渐减弱。而反映有丝分裂期的特异性蛋白磷酸组蛋白H3随时间表达逐渐减少,且表达强度基本与细胞周期素A2表达减弱相一致。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

Geranylated flavanone tomentodiplacone B inhibits proliferation of human monocytic leukaemia (THP-1) cells

BACKGROUND AND PURPOSE

Paulownia tomentosa is a rich source of geranylated flavanones, some of which we have previously shown to have cytotoxic activity. To identify members of this class of compounds with cytostatic effects, we assessed the effects of the geranylated flavanone tomentodiplacone B (TOM B) on cell cycle progression and cell cycle regulatory pathways of THP-1 human monocytic leukaemia cells.

EXPERIMENTAL APPROACH

Cell viability was measured by dye exclusion and proliferation by WST-1 assays; cell cycle was monitored by flow cytometry. Regulatory proteins were assessed by immunoprecipitation and kinase assays, and Western blotting.

KEY RESULTS

Tomentodiplacone B had no effect during the first 24 h of cell growth at concentrations between 1 and 2.5 µM, but inhibited cell growth in a dose-dependent manner at concentrations of 5 µM or higher. Growth inhibition during the first 24 h of exposure to TOM B was not accompanied by cytotoxicity as cells were accumulated in G1 phase dose-dependently. This G1 phase accumulation was associated with down-regulation of cyclin-dependent kinase 2 activity and also protein levels of cyclins E1 and A2. However, key stress-related molecules (γ-H2AX, p53 and p21) were not induced, suggesting that TOM B acts by directly inhibiting the cyclin-dependent kinase 2 signalling pathway rather than initiating DNA damage or cellular stress.

CONCLUSIONS AND IMPLICATIONS

Our study provides the first evidence that TOM B directly inhibits proliferation of human monocytic leukaemia cells, and thus is a potential anticancer agent, preventing leukaemia cells from progressing from G1 phase into DNA synthesis.     

EGF对真皮成纤维细胞中cyclinD1和CDK-4表达的影响

目的　探讨表皮生长因子 (EGF)对作为皮肤组织工程种子细胞之一的真皮成纤维细胞中 cyclin D1和 CDK- 4表达的影响 ,以从细胞周期探讨 EGF促进真皮成纤维细胞生长的机制 .方法　用含 10 0 m L· L- 1 胎牛血清的 DMEM,加入5 0 mg· L- 1的 EGF培养 SD大鼠的真皮成纤维细胞 ,通过MTT检测、流式细胞仪分析观察细胞的生长状态 ,免疫组化检测 cyclin D1和 CDK- 4的表达 ,结合流式细胞仪分析观察细胞的周期变化 .结果　 MTT检测、流式细胞仪结果都显示 5 0mg· L- 1 的 EGF能显著促进真皮成纤维细胞的生长增殖 ,免疫组化结果显示 ,二者一致 .结论　 5 0 mg· L- 1 的 EGF对真皮成纤维细胞的生长有极大的促进作用 ,促进了细胞周期蛋白 cyclin D1和 CDK- 4的表达 ,使细胞 G1期变短 .     

p27 downregulation and metallothionein overexpression in gastric cancer patients are associated with a poor survival rate

BACKGROUND AND OBJECTIVES: As a significant number of curatively treated gastric cancer patients will ultimately relapse, there is an urgent need to investigate new prognostic markers for identification of high-risk patients. In this study, we investigated the possible role of molecular markers involved in cell cycle regulation (B1 and D3 cyclins, and p27) and cell protection (metallothionein, MT) in predicting tumor behavior and clinical outcome in gastric cancer patients. METHODS: Analysis of the above indicators was performed by immunohistochemistry on 73 gastric cancer patient samples and 25 normal gastric mucosa specimens. RESULTS: Normal gastric mucosa cells displayed low expressions of B1 and D3 cyclins and MT, and intense p27 staining. Conversely, gastric tumor cells showed higher cyclin D3 and MT, and lower p27 expressions. B1 cyclin expressions were not different between normal and tumor tissue. p27 and MT expressions were altered in almost all cancer samples, and were strongly correlated with tumor progression. Advanced extent of the primary tumor, nodal metastasis, low p27, and high MT expressions were the best combination of variables for prediction of poor clinical outcome. Each marker predicted outcome better than staging based on tumor-node (TNM) system. Survival and recurrence rates decreased as molecular alterations increased. Finally, molecular profile determination correctly predicted the prognosis in patients with same TNM stage. CONCLUSIONS: p27 and MT expressions strongly correlated with clinical outcome allowing to identify an unfavorable group of patients that may benefit from tailored treatments. The role of B1 and D3 cyclins in gastric cancer remains to be elucidated.