Treatment of Relapsing and Refractory Adult Acute Myeloid Leukemia According to in vitro Clonogenic Leukemic Cell Drug Sensitivity

In an attempt to improve the results of treatment in patients with relapsing or refractory acute myeloid leukemia (AML), we conducted a pilot study using a two-drug salvage regimen according to the in vitro clonogenic leukemic cell (CFU-L) drug sensitivity. Fourteen patients were included in the study, 10 with relapsing and 4 with refractory AML. Drug exposure was assessed for daunorubicin, cytosine arabinoside, etoposide, mitoxantrone and amsacrine. The two drugs with the best inhibitory effect on CFU-L were selected for the treatment. A complete remission was achieved in only 4 patients and a partial remission in 3 patients. Although the number of patients is too small for appropriate statistical analysis and for a definite conclusion to be drawn, the observed response rate with directed therapy did not appear better than that expected from empiric salvage regimen.     

“Antivirals” in the Treatment of Adult T Cell Leukaemia– Lymphoma (ATLL)

Adult T cell leukaemia / lymphoma (ATLL) is a mature (post thymic) T cell lymphoma caused by the human T-lymphotropic virus type 1 (HTLV-1) infection. Overall survival in the aggressive subtypes (Acute Leukaemia and Lymphomatous) remains poor in part due to chemotherapy resistance. To improve treatment outcome for de novo disease, better induction therapies are required and since the pathogenic agent is known it would seem sensible to target the virus. In a recent meta-analysis the use of zidovudine and interferon alpha (ZDV/IFN) has been associated with improved response rates and prolonged overall survival in leukemic subtypes of ATLL (both acute and Chronic) confirmed in a multivariate analysis. In a more recent UK study the overall response rate for patients with aggressive ATLL treated with chemotherapy alone was 49?% compared to 81?% with combined first line therapy (chemotherapy with concurrent or sequential ZDV/IFN). Combined first line therapy prolonged median OS in acute (p?=?0.0081) and lymphomatous ATLL (p?=?0.001).These data support the use of low dose ZDV/IFN with chemotherapy as first line treatment for patients with newly diagnosed aggressive ATLL. Although the mechanisms of action are incompletely understood, some possible explanations for their efficacy will be discussed.     

Development and Partial Characterization of a Human T-Lymphoblastic Leukemic (CCRF-CEM) Cell Line Resistant to Etoposide. Analysis of Possible Circumventing Approaches

Abstract

We have selected an etoposide-resistant variant (CCRF-CEM\VP-16) of the human T-lymphoblastic CCRF-CEM leukemia for study. Resistance to the topoi-somerase II (topo II) inhibitor was about 11-fold and stable. Other data revealed that the new cell line had acquired an atypical, non-P-glycoprotein overexpressing multidrug resistant (MDR) phenotype with cross-resistance to other topo II inhibitors (amsacrine, doxorubicin, and mitoxantrone) and to glucocorticoids, but not to novobiocin, ICRF-187, vincristine or cisplatin. In a first instance, we assumed that altered drug-topo II interactions, based on quantitative and/or qualitative modifications of the enzyme, are a cause of resistance in the cell line. We tried to modify the drug sensitivity of the cells by means of various agents and cytokines. Positive results were obtained with verapamil and, to a lesser extent, cyclosporin A, but they were not specific for the drug resistant variant and occurred in the parental CCRF-CEM as well. Other attempts with buthionine sulfox-imine, novobiocin, pentoxifylline, interleukin-1, interfer-on-alpha, retinoic acid, TNF-alpha, bryostatin 1 or phor-bol myristate acetate were substantially unsuccessful, thus confirming the difficulty of pharmacologically overcoming atypical MDR. More encouragingly, however, CCRF-CEM\VP-16 cells exhibited hypersensitivity to other agents, including actinomycin D and taxol.     

非小细胞肺癌患者血清CA125水平与疾病进展时间的相关性

[目的]评价非小细胞肺癌(NSCLC)患者血清糖类抗原(CA125)水平与疾病进展时间(TTP)的关系。[方法]对中国中医科学院广安门医院2006年10月～2009年10月收治的154例非小细胞肺癌患者的血清CA125水平与疾病进展时间的相关性进行回顾性研究。[结果]血清CA125水平与临床分期相关,Ⅳ期患者血清CA125水平明显高于ⅢB期(P<0.05)。血清CA125水平≥123U/ml的患者半年内进展的风险比CA125水平<123U/ml的患者增加89%(OR=1.889,95%CI:1.254～2.845,P=0.002)。[结论]血清CA125水平与患者疾病进展时间有明显的相关性,可通过检测CA125水平判断患者预后。     

Molecular Response to Imatinib and Its Correlation with mRNA Expression Levels of Imatinib Influx Transporter (OCT1) in Indian Chronic Myeloid Leukemia Patients

Background and objectives: Imatinib mesylate is approved for the treatment of Chronic Myeloid Leukemia (CML). About 20% of patients with CML do not respond to treatment with Imatinib either initially or because of acquired resistance. In addition to mutated BCR-ABL1 kinase, the organic cation transporter1 (OCT1, encoded by SLC22A1) has been considered to contribute to Imatinib resistance in patients with chronic myeloid leukemia (CML). OCT1 has been reported to be the main influx transporter involved in Imatinib uptake into CML cells. To date, only a few studies have been reported on involvement of influx transporters in development of Imatinib resistance. Therefore this study was aimed to determine the expression level of Imatinib uptake transporter (OCT1) in CML patients and to correlate this level with molecular response. Methods: One hundred fifty eight patients on Imatinib were considered for gene expression analysis study for OCT1 gene. Total RNA was extracted from peripheral blood mononuclear cells. Complementary DNAs (cDNAs) were synthesized and Real Time Polymerase Chain Reaction (RQ-PCR) was performed. Results: High OCT1 expression was present in 81 (51.8%) patients and low OCT1 expression was in 77 (48.7%) patients. Low Sokal risk score group have a significantly high OCT1 expression (p=0.048). The rate of molecular response was higher in those with high OCT1 expression than in those with low OCT1 expression (p=0.05). Both event-free survival and median overall survival were significantly shorter in patients with low OCT1 expressions when compared to the patients with high OCT1 expression (p=0.03 and p=0.05). Conclusions: Our findings demonstrated that the mRNA expression level of OCT1 was significantly correlated with molecular response in CML patients. Based on these findings, present study believes that the pre-therapeutic higher expression of OCT1 may help to predict response to imatinib therapy in CML patients.     

High-Dose Cytarabine (HD araC) in the Treatment of Leukemias: a Review

Cytarabine (araC) has served as the backbone of acute myeloid leukemia (AML) treatment for nearly forty years. High-dose cytarabine (HD araC) therapy resulted from a theoretical model developed in the 1970s that attempted to maximize the anti-leukemia effect of cytarabine. Since that time, HD araC has been utilized mostly in consolidation therapy for AML and in patients with relapsed or resistant AML. The development of araC and HD araC preceded our current understanding of AML biology–that it is a heterogeneous disease, not a single clinical entity. Thus, the optimal dose, schedule, and clinical setting for the use of cytarabine in hematologic malignancies remain uncertain. Research is now better defining the optimal use of HD araC based on leukemia cell karyotype and molecular signature. Here we review the pharmacodynamics of araC, the landmark studies that established the role of HD araC in AML, and research defining the role of HD araC based on the unique biologic properties of the leukemia cell.     

褪黑素对阿霉素抗ER~+乳腺癌细胞MCF-7作用的影响及其机制

目的:探讨生理浓度(10~(-9)mol/L)褪黑素和药理浓度(10~(-5)mol/L)褪黑素对阿霉素抑制ER~+乳腺癌细胞MCF-7作用影响及其机制.方法:1)应用四甲基偶氮唑蓝(MTT)法检测经不同浓度褪黑素孵育后阿霉素对MCF-7的抑制率和IC_(50)变化.2)应用流式细胞学方法观察不同浓度褪黑素、阿霉素以及两药联用时对MCF-7凋亡的影响.3)应用Western blotting法检测不同浓度褪黑素、阿霉素单药和两药联用对MCF-7细胞p53和bcl-2蛋白表达的影响.结果:1)阿霉素对MCF-7乳腺癌细胞具有明显的抑制作用,且成剂量时间依赖性.IC_(50)值为0.62±0.07μg/ml,经生理浓度和药理浓度褪黑素孵育后IC_(50)值分别降为0.59±0.09μg/ml和0.42±0.02μg/ml,前者与孵育前相比未见统计学差异(P>0.05),后者相比差异显著(P<0.01).2)流式细胞学检测结果显示:阿霉素对MCF-7细胞具有凋亡促进作用,随浓度增高凋亡率未见增加(P>0.05).生理浓度褪黑素联合阿霉素与相应浓度的阿霉素单药相比,凋亡率未见明显增加(P>0.05).药理浓度褪黑素联合阿霉素与相应浓度阿霉素单药比较,凋亡率明显增加(P<0.05),联合组随着阿霉素浓度增加凋亡率并未见明显变化(P>0.05).3)MCF-7乳腺癌细胞株中呈p53蛋白低表达、bcl-2蛋白高表达.生理浓度褪黑素即可显著增高MCF-7细胞p53蛋白并降低bcl-2蛋白表达,并有剂量依赖性(P<0.01).药理浓度褪黑素联合不同浓度阿霉素对两个蛋白表达未见显著性差异(P>0.05);阿霉素对两种蛋白表达未见明显影响(P>0.05).结论:1)生理浓度褪黑素(10~(-9)mol/L)对阿霉素的抗癌作用未见明显影响,药理浓度(10~(-5)mol/L)以上褪黑素表现出对阿霉素明显的增敏作用.2)阿霉素较低浓度时,凋亡促进作用可能是褪黑素对其增敏机制的一部分,随着阿霉素浓度的提高,褪黑素的细胞毒增敏机制可能占主要地位.3)生理浓度褪黑素能提高ER~+乳腺癌细胞p53蛋白表达并降低bcl-2蛋白表达,并具有剂量依赖性.涉及p53和bcl-2的凋亡通路可能是褪黑素对阿霉素增敏机制的一部分.     

K562及其耐药细胞株K562／A02对rmhTRAIL的敏感性及NF-κB表达

[目的]探讨K562及其耐药细胞株K562／A02对rmhTRAIL敏感性及NF-κB（RelA／p65）的表达。[方法]观察rmhTRAIL作用后K562、K562／A02细胞形态变化，采用碘化丙啶染色法流式细胞术定量检测细胞凋亡比例，MTT法测定rmhTRAIL抑制细胞增殖率，半定量逆转录-聚合酶链反应（RT—PCR）方法检测K562、K562／A02细胞的NF-κB（RelA/p65）mRNA表达水平。[结果]rmhTRAIL可诱导K562、K562／A02细胞凋亡，有典型的细胞形态改变；流式细胞术检测显示K562／A02的sub—G1百分比大于K562（P〈0．05）；rmhTRAIL对K562／A02的增殖抑制作用优于K562（P〈0．05）；K562和K562／A02均高表达NF-κB（RelA/p65）mRNA，两者无统计学意义（p〉0．05）。[结论]rmhTRAIL可以诱导K562、K562／A02细胞凋亡；rmhTRAIL对K562／A02促凋亡和抑制增殖作用优于K562；NF-κB（RelA／p65）未显示出其在K562及其耐药细胞株K562／A02对rmhTRAIL敏感性差异中的作用。     

Evaluation of Apoptotic Gene Expression in Hepatoma Cell Line (HepG2) Following Nisin Treatment

Objective: The present study aims to examine the effects of nisin on the survival and apoptosis of the hepatoma cell line HepG2 and to investigate possible apoptosis pathways activated by nisin. Materials and Methods: For this purpose, viability and apoptosis of the cells were accomplished by the nisin treatment using the MTT assay and Annexin-V-fluorescein/propidium iodide (PI) double staining, respectively. Additionally, the human apoptosis PCR array was performed to determine pathways or genes activated by nisin during possible apoptosis. Results: The results of the present study showed that nisin was able to decrease cell viability (IC50 ~ 40 µg/ml) in a dose-dependent manner and could induce apoptosis in HepG2 cells. PCR data indicated a considerable increase in the expression of genes, such as caspase and BCL2 families, involved in the induction of apoptosis. Conclusions: The data from this study showed that overexpression of genes involved in the intrinsic pathway of apoptosis, especially caspase-9 and BID, increased apoptosis in HepG2 cells treated by nisin, compared to the control group.     

4-羟苯基维甲酰胺对膀胱癌细胞的放疗增敏性研究

目的:观察N-(4-羟苯基)维甲酰胺(4-HPR)联合γ-射线对人膀胱移行细胞癌的生长抑制和诱导凋亡作用,分析两者之间是否存在协同作用.方法:应用四甲基偶氮蓝比色(MTT)法检测4-HPR对膀胱癌细胞株T24的细胞毒性作用、半数抑瘤率及起效浓度和时间.应用流式细胞仪检测4-HPR、γ-射线及两者联合应用时对T24细胞生长抑制作用.结果:2.5μmol/L、5μmol/L、10μmol/L的4-HPR作用T24细胞5天的凋亡率分别为6.2%、28.0%和26.0%,死亡率分别为0.3%、12.5%和26.7%.联合作用组细胞分别加入2.5μmol/L、5μmol/L的4-HPR,100cgy的γ-射线照射一次,3天后T24细胞的凋亡率分别为20.0%、26.0%,细胞的死亡率均在5.0%以下.5天后T24细胞的凋亡率分别为38.0%、35.0%,而细胞的死亡率分别为12.4%、21.1%.结论:小剂量的4-HPR可以诱导T24细胞凋亡,大剂量的4-HPR主要导致T24细胞死亡.小剂量的4-HPR联合小剂量的γ-射线对T24细胞凋亡有明显的协同作用.     

中药R_3(补骨脂抽提剂)对耐阿霉素人乳腺癌细胞MCF_7~(adr)多药耐药的逆转

耐阿霉素人乳腺癌细胞MCF7adr具多药耐药（Multidxugresistance，MDR）表型。补膏脂抽提剂R3（粉剂）的无细胞毒浓度1：90（2mg／ml）、1：60（3mg／ml）及1：30（6mg／ml），可增加MCF7adr对可霉素（Adriamycin，ADM）的敏感性10．4倍、292倍及730倍。1：90R3＋异搏定（Vera－Pamil，VPL）10μM使MCF7adr对CAM敏感性由10．4倍增至122倍。提示二者有协同作用。流式细胞技术（FCM）显示R3可明显增加MCF7adr细胞内Rh0－123含量。免疫细胞化学技术结果示R3可完全抑制卜糖蛋白（P－glycoprotein，Pgp）表达，是时间依赖性，48小时后MCF7adr细胞Pgp表达完全消失。故提示Ra可能通过抑制Pgp功能，增加ADM在MCF7adr细胞中浓度调控MCF7adr的耐药性。     

P型铜转运ATP酶(ATP7B)在肺腺癌细胞株A549中的表达与顺铂耐药的关系

背景与目的 顺铂作为肺癌的基础化疗药物,顺铂耐药是导致肺癌患者化疗失败的重要原因.本实验通过检测P型铜转运ATP酶在肺腺癌细胞A549不同水平耐药株中的表达,以评估ATP7B与A549细胞顺铂耐药的关系.方法采用逐步增加顺铂剂量的方法,诱导出3株不同水平耐顺铂A549细胞株A549/DDP0.5、A549/DDP1.0、A549/DDP2.0,MTT方法检测各组别细胞对顺铂敏感性,应用RT-PCR及Western Blot方法分别检测各组别细胞的ATP7B的mRNA及蛋白表达水平,分析A549细胞顺铂敏感性与ATP7B表达水平的关系.结果相对于亲本A549细胞,3组耐药细胞的顺铂耐药指数分别达到了1.7、3.2、5.2(P＜0.001),与此相对应ATP7B的mRNA表达水平分别达到了亲本A549细胞的1.6、4.9、10.1倍(P＜0.001),同样地ATP7B的蛋白表达水平也呈现出与顺铂耐药性相平行的递增性高表达.结论肺腺癌细胞A549的顺铂耐药与细胞ATP7B高表达有关,后者的高表达有可能促成了A549细胞的获得性顺铂耐药.     

On the Phosphorylation of 2-chlorodeoxy-adenosine (CdA) and Its Correlation with Clinical Response in Leukemia Treatment

The nucleoside analog 2-chlorodeoxyadenosine (CdA, Cladribine) is a chemotherapeutic agent for treatment of leukemias and lymphomas, most successfully used in hairy cell leukemia and B-cell chronic lymphocytic leukemia. CdA is phosphorylated intracellularly to its monophosphate derivative by the enzymes deoxycytidine kinase and deoxyguanosine kinase. Cell lines deficient in deoxy-cytidine kinase were shown to be resistant to CdA and a high deoxycytidine kinase level in combination with low 5'-nucleotidase has been proposed to partly explain the selectivity in CdA toxicity for lymphoid cells. In this report biochemical properties in CdA phosphorylation mediated by deoxycytidine kinase and deoxyguanosine kinase are reviewed and discussed in relation to the further metabolism of CdA 5'-monophosphate, the different possible mechanisms of action and the correlation with clinical response. It is concluded that much is known about the metabolism and mechanisms of action of CdA, but that the remarkable therapeutic effect in hairy cell leukemia has yet to be explicitly explained.     

BRAF,KRAS and PIK3CA Mutation and Sensitivity to Trastuzumab in Breast Cancer Cell Line Model

Studies show that approximately 20% of all breast cancer patients have a breast tumor that tests positive for Human Epidermal Growth Factor Receptor 2, otherwise known as the HER2 gene. As such, treatments for breast cancer usually include drugs that target HER2. The drug Trastuzumab is a recombinant antibody that has been approved by the FDA for the treatment of these HER2 positive breast cancers. However, researchers have found that mutations in associated genes, PIK3CA and KRAS, can cause the tumor to become resistant to Trastuzumab. The purpose of this article is to evaluate the sensitivity of the cancer cell lines to the drug Trastuzumab and investigate how this sensitivity is compromised by the PIK3CA, KRAS and BRAF gene mutations. Trastuzumab responsiveness was evaluated in breast cancer cell lines by treating the lines with an optimal concentration of the drug followed by a proliferation assay of the cell lines in the presence of monoclonal antibodies. We determined the optimum concentration of Trastuzumab to be 7 μg/well. The BRAF and KRAS mutated cell line, MDA-MB-231, showed the least sensitivity after being treated with trastuzumab when compared to the sensitivity of the PIK3CA mutated cell lines, MCF-7 and MDA-MB-361, and the KRAS/ BRAF/ PIK3CA cell line, MDA-MB-453. Clinical observations show that mutations in BRAF and KRAS genes in breast cancer cells do lower the responsiveness of Trastuzumab drug treatments.