酪氨酸激酶抑制剂STI571与P21WAF基因克隆治疗慢性粒细胞白血病的实验研究

本研究探讨酪氨酸激酶抑制剂ST1571和P21^WAF基因克隆对慢性粒细胞白血病急变K562细胞株的细胞增殖、细胞周期及凋亡等的治疗作用。RT—PCR扩增P21^WAF基因，胶纯化回收后连接到T载体测序，序列正确后构建P21—pcDNA3．1栽体，将P21—pcDNA3．1与空载体分别以脂质体转染入P21蛋白表达缺如的K562细胞，经筛选得到G418抗性的K562细胞株，Westernblot证实转染后有P21蛋白表达，MTT法检测细胞存活率，流式细胞仪检测细胞周期和凋亡。结果表明：表达外源性P21蛋白的P21—pcDNA3．1-K562细胞株生长速度明显慢于对照K562细胞株，流式细胞仪显示G0／G1期细胞增多，MTT法显示P21—pcDNA3．1-K562细胞与ST1571联合应用后，与单用ST1571作用的K562细胞相比，凋亡细胞比例轻度减少，细胞存活率下降较慢。结论：表达外源P21蛋白能抑制K562细胞增殖，同时对ST1571的促凋亡作用有轻度抑制，并降低K562细胞对ST1571的敏感性。     

Blocking CD30 on T Cells by a Dual Specific CAR for CD30 and Colon Cancer Antigens Improves the CAR T Cell Response against CD30− Tumors

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靶向ADAM17基因siRNA对前列腺癌PC-3细胞增殖能力的影响

目的:探讨靶向抑制ADAM17基因对雄激素非信赖性前列腺癌PC-3细胞增殖的影响。方法:应用ADAM17 siRNA转染PC-3细胞后,通过RT-PCR、Western印迹方法分别检测ADAM17 mRNA和蛋白表达变化;MTT、BrdU掺入法检测下调ADAM17对PC-3细胞的增殖和DNA合成能力的影响;流式细胞术检测ADAM17 siR-NA对PC-3细胞细胞周期的影响;Western印迹检测下调ADAM17对PC-3细胞增殖相关基因表达的影响。结果:两对ADAM17 siRNAs均可有效地降低PC-3细胞ADAM17 mRNA和蛋白的表达;MTT结果显示与对照组(0.80±0.51)相比,两对ADAM17 siRNAs均可显著抑制细胞的生长(0.43±0.57、0.44±0.64,P均<0.05);Br-dU掺入实验显示与对照组(0.79±0.72)相比,ADAM17 siRNAs均能显著下调DNA的合成能力(0.48±0.43、0.54±0.59,P<0.05);流式细胞术结果显示,与对照组(41.38±1.53)%相比,ADAM17 siRNAs可显著增加G1期细胞数量[(61.83±2.41)%、(59.78±1.92)%,P均<0.05]、降低S期细胞数量[从(33.51±1.47)%减少到(23.64±2.56)%、(25.24±1.86)%,P均<0.05],同时伴随着cyclin D1蛋白的表达下降而p21蛋白的表达升高。结论:ADAM17 siRNA可以通过下调cyclin D1、上调p21的表达而抑制前列腺癌PC-3细胞增殖,ADAM17可能成为前列腺癌基因治疗的靶点。     

Expression of the tumour antigen T21 is up-regulated in prostate cancer and is associated with tumour stage

What's known on the subject? and What does the study add? T21 is an immunogenic prostate‐associated tumor antigen identified by SEREX expression cloning and shown to have a highly restricted mRNA expression profile. This study shows the expression of T21 at the protein level in a panel of tissues and cell lines and demonstrates increasing levels of T21 protein expression in patients with more advanced stage prostate cancer.

OBJECTIVES

• ? To define the expression pattern of the tumour antigen T21 at the protein level in prostate tissues, prostate cell lines and a panel of normal tissues.
• ? To correlate the expression pattern of T21 in prostate cancer with clinical parameters.

PATIENTS AND METHODS

• ? Tissue samples were collected from 79 patients presenting at clinic with either prostate cancer (63 patients) or benign prostatic hyperplasia (BPH, 16 patients).
• ? A tissue microarray (TMA) was constructed from 44 of the prostate cancer tissues and areas of benign disease (43 patients) from these tissues were also included on the TMA. The remaining tissues (prostate cancer 19 patients and BPH 16 patients) were mounted fresh frozen onto cork boards and sectioned.
• ? Full ethical approval was granted for all aspects of the study and informed patient consent was taken before tissue collection.
• ? Immunohistochemistry was used on the prostate tumour TMA, the normal tissue TMA and the fresh‐frozen prostate tissues. Fluorescent microscopy and flow cytometry was performed on prostate cell lines.

RESULTS

• ? Expression of T21 was highly restricted within normal tissues with only the stomach, ovary, breast and prostate having detectable T21 expression.
• ? T21 was significantly over‐expressed in prostate cancer glands compared with benign tissue and was present in >80% of the malignant specimens analysed.
• ? Increased expression was positively correlated to pathological stage of prostate tumours.
• ? Additionally, T21 was associated with Gleason grade and prostate‐specific antigen recurrence, although statistical significance was not reached in this restricted cohort of patients.

CONCLUSION

• ? Taken together these results show that T21 is a potential new biomarker for advanced disease and that elevated levels of T21 appear relevant to prostate cancer development.

     

Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis,neuropathology and glucocorticoid-based therapeutics

Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics.     

Higher frequency of peripheral blood follicular regulatory T cells in patients with new onset ankylosing spondylitis

Follicular helper T (TFH) cells and B cells are linked to the pathogenesis of ankylosing spondylitis (AS). Follicular regulatory T (TFR) cells suppress TFH cell and germinal center B cell numbers in vivo. The role of TFR cells in AS is unknown. The frequency of peripheral blood inducible FOXP3+CXCR5+CD4+TFR cells and CXCR5+CD4+TFH cells were taken from 20 onset AS patients and 10 healthy controls, and were examined by flow cytometry, their disease activity were measured by the Bath Ankylosing Spondylitis Disease Activity Index. The concentrations of serum interleukin (IL)‐21, immunoglobulin G, immunoglobulin A, immunoglobulin M and C‐reactive protein were examined, and the values of erythrocyte sedimentation rate were measured. The frequency of peripheral blood FOXP3+CXCR5+CD4+TFR cells, CXCR5+CD4+TFH cells, the ratio of FOXP3+CXCR5+CD4+TFR/CXCR5+CD4+TFH cells and the concentration of serum IL‐21 in the AS patients were significantly higher than those in the healthy controls (P < 0.0001, P = 0.0027, P < 0.0001, P = 0.0039, respectively). The frequency of FOXP3+CXCR5+CD4+TFR cells and the ratio of FOXP3+CXCR5+CD4+TFR/CXCR5+CD4+TFH cells still significantly rose in those patients after standard treatment (P = 0.0006, P < 0.0001), the concentration of serum IL‐21 decreased after treatment (P = 0.0049), accompanied by significantly minimized disease activities. Furthermore, the TFR cells were negatively correlated with serum immunoglobulin A in those patients before treatment (r = ?0.582, P = 0.0071), and the frequency of TFR cells was negatively correlated with that of TFH cells and the concentration of serum IL‐21 after treatment (r = ?0.550, P = 0.046; r = ?0.581, P = 0.0371). TFR cells might participate in the pathogenesis of AS, and might be responsible for controlling the autoantibodies, the frequency and function of TFH cells to inhibit the development of AS.     

Mechanism of adrenocortical toxicity induced by quinocetone and its bidesoxy-quinocetone metabolite in porcine adrenocortical cells in vitro

Quinocetone (QCT) is a new feeding antibacterial agent in the QdNOs family. The mechanism of its adrenal toxicity is far from clear. This study was conducted to estimate the adrenal cell damage induced by QCT and its bidesoxy-quinocetone (B-QCT) metabolite and to further investigate their mechanisms. Following doses of QCT increasing from 5 to 50 μM, cell apoptosis and necrosis, mitochondrial dysfunction and redox imbalance were observed in porcine adrenocortical cells. The mRNA levels of the six components of intermediary enzymes and the adrenal renin-angiotensin-aldosterone system (RAAS) displayed a dysregulation induced by QCT, indicating that QCT might influence aldosterone secretion not only through the upstream of the production but also through the downstream of the adrenal RAAS pathway. In contrast, B-QCT had few toxic effects on the cell apoptosis, mitochondrial dysfunction and redox imbalance. Moreover, LCMS-IT-TOF analysis showed that no desoxy metabolites of QCT were found in either cell lysate or supernatant samples. In conclusion, we reported on the cytotoxicity in porcine adrenocortical cells exposed to QCT via oxidative stress, which raised awareness that its toxic effects resulted from N→O groups, and its toxic mechanism might involve the interference of the steroid hormone biosynthesis pathway.     

乌索酸通过抑制miR-21表达诱导肝癌HepG2细胞凋亡的机制

探讨乌索酸通过调控miR-21表达从而诱导肝癌HepG2细胞凋亡的作用机制。采用MTT方法检测乌索酸对肝癌细胞增殖的抑制作用;qPCR检测肝癌细胞中miR-21的表达水平及乌索酸对HepG2细胞中miR-21表达的调控作用;转染miR-21 mimics进HepG2细胞中上调miR-21的表达后,MTT、流式细胞检测法、RT-PCR方法分别分析miR-21在乌索酸对细胞的增殖、凋亡以及对凋亡相关基因的调控过程中的作用。结果显示,与肝正常细胞L-02以及肝癌SMCC-7721、Bel-7402细胞相比较,乌索酸对肝癌HepG2细胞的增殖抑制效果最强,且HepG2细胞中miR-21的表达水平最高。乌索酸可下调HepG2细胞中miR-21的表达,且在24 h的下调作用最强。miR-21的表达上调可以部分抵消乌索酸对HepG2细胞的抑制增殖及促进凋亡,部分抵消下调凋亡抑制基因Bcl-2、survivin表达和上调促凋亡基因Bax表达的作用。结果提示,乌索酸通过抑制miR-21的表达诱导肝癌HepG2细胞凋亡。     

MiR-21通过PTEN/PI3K/AKT信号通路抑制胰腺癌细胞系生长侵袭能力的体外研究

目的 探讨MiR-21对胰腺癌细胞生长和侵袭的影响.方法 采用脂质体Lipofectamine 2 000将MiR-21 inhibitor和MiR-21 inhibitor阴性对照转染至胰腺癌细胞ASPC-1,qRT-PCR检测转染效果,细胞免疫荧光、Western blot检测转染后目的蛋白的表达,Transwell、划痕实验检测细胞迁移侵袭能力,MTT法检测细胞的增殖活性,流式细胞术检测细胞周期分布的改变.结果 成功构建稳定下调MiR-21的胰腺癌细胞亚系ASPC-1-MiR-21,荧光定量PCR结果显示MiR-21表达量明显下调,抑制MiR-21表达后ASPC细胞的侵袭和增殖能力均受到明显抑制;抑制MiR-21能明显增强PTEN蛋白和减低p-AKT蛋白表达水平,对AKT蛋白水平无明显影响.结论 抑制MiR-21表达可能通过调控PTEN/AKT通路抑制胰腺癌细胞AS-PC-1增殖和侵袭.     

Fibroblast growth factor-21 is positively associated with atrial fibrosis in atrial fibrillation patients with rheumatic heart disease

Objective: Fibroblast growth factor-21 (FGF-21) has been discovered as a strong hormone, plays an important role in lipid metabolism, glucose metabolism, associated with several diseases such as obesity, metabolic syndrome, diabetes mellitus, and cardiovascular events; however, no evidence is available concerning the relationship of FGF-21 and atrial fibrosis in patients with atrial fibrillation (AF) and rheumatic heart disease (RHD). Methods: Twenty-four rheumatic heart disease patients were divided into two groups, 12 cases with AF and 12 cases with sinus rhythm (SR). Clinical characteristics and blood samples were collected before surgery; right atrial appendage samples were taken in the surgery of valve replacement. HE staining was performed to determine cross-sectional area of atrial myocytes; Masson stained sections and mRNA levels of cardiac fibrosis biomarkers were used to evaluate the degree of cardiac fibrosis; the level of FGF-21 was evaluated via enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, and real-time polymerase chain reaction (PCR). Results: Compared with SR group, cross-sectional area of atrial myocytes and collagen volume fraction were significantly increased in the atrial tissue of AF group. The distribution of FGF-21 in the AF group was remarkably higher than SR group. In addition, plasma and mRNA levels of FGF-21 in atrial tissue of AF showed the same trend as the result of immunohistochemistry. Using linear correlation analysis, the expression level of FGF-21 was found to be positively related to the degree of atrial fibrosis. Conclusion: FGF-21 might involve in the development and maintenance of atrial fibrosis in atrial fibrillation with rheumatic heart disease, and FGF-21 could be used as a novel biomarker to evaluate myocardial fibrosis in the future.