Using next-generation sequencing as a genetic diagnostic tool in rare autosomal recessive neurologic Mendelian disorders

Next-generation sequencing was used to investigate 9 rare Chinese pedigrees with rare autosomal recessive neurologic Mendelian disorders. Five probands with ataxia-telangectasia and 1 proband with chorea-acanthocytosis were analyzed by targeted gene sequencing. Whole-exome sequencing was used to investigate 3 affected individuals with Joubert syndrome, nemaline myopathy, or spastic ataxia Charlevoix-Saguenay type. A list of known and novel candidate variants was identified for each causative gene. All variants were genetically verified by Sanger sequencing or quantitative polymerase chain reaction with the strategy of disease segregation in related pedigrees and healthy controls. The advantages of using next-generation sequencing to diagnose rare autosomal recessive neurologic Mendelian disorders characterized by genetic and phenotypic heterogeneity are demonstrated. A genetic diagnostic strategy combining the use of targeted gene sequencing and whole-exome sequencing with the aid of next-generation sequencing platforms has shown great promise for improving the diagnosis of neurologic Mendelian disorders.     

Terapia celowana i transplantacja komórek krwiotwórczych szansą na wyleczenie chorych z ostrą białaczką szpikową

Acute myeloid leukemia (AML) is a heterogeneous disorder with a diverse prognosis. About 70% of AML patients may achieve complete remission after conventional chemotherapy, but long-term outcome remains unsatisfactory. The development of molecular biology resulted in a better understanding of AML pathogenesis as well as it allowed us the introduction of targeted therapy. However, most AML patients still require the allogeneic hematopoietic stem cell transplantation (alloHSCT) to be cured. The long-term results of alloHSCT for AML depend on a variety of factors including the age at transplant, the presence of well-defined risk factors and disease status at transplant. It seems that the combination of targeted therapy with conventional chemotherapy and subsequent alloHSCT may be a chance for curing a significant proportion of AML patients.     

Targeting the Vascular Endothelial Growth Factor Pathway in the Treatment of Human Malignancy

Over 30 years ago, it was proposed that blocking new blood vessel formation would significantly inhibit solid tumor growth and hence, limit cancer progression. Efforts guided by this philosophy have resulted in a better understanding of the molecular basis of tumor angiogenesis. The first successful therapeutic to emerge from this work, an antibody (bevacizumab) targeting the vascular endothelial growth factor (VEGF), was recently approved for the treatment of colorectal cancer. Additional positive clinical data with bevacizumab in the treatment of breast and lung carcinoma have also been reported. These clinical achievements have validated the approach of anti-angiogenesis therapy for cancer and provided further confirmation for antibodies as a therapeutic class in this disease. Nevertheless, important unanswered questions with regard to preclinical and clinical results of VEGF pathway inhibitors remain. For example, preclinical models with a number of VEGF pathway inhibitors suggest that these agents would have significant clinical activity on their own; yet, clinical activity in patients with bevacizumab or other VEGF pathway inhibitors as monotherapy have been disappointing. Moreover, while bevacizumab is approved for the treatment of colorectal cancer in combination with cytotoxics, the mechanism for the benefits of this combination are still poorly understood, with a number of viable mechanisms under active experimental evaluation. The 3–8-month survival benefit in colorectal cancer patients treated with bevacizumab is a positive step forward. However, improving our understanding of the mechanism for these effects, as well as the mechanism underlying the inability as yet to achieve greater effects, is needed in order to follow up on the positive clinical results with improved strategies. This review discusses the experimental results surrounding the current status of our understanding of the mechanism of action of VEGF signaling inhibitors, and the potential for utilizing these agents in the future so that clinical benefits will be measured in years rather than months.     

东亚钳蝎氯毒素在胶质瘤靶向显像与治疗中的研究进展

神经胶质瘤是颅内最常见的肿瘤,尤其是恶性胶质瘤,具有高复发率和致死率的特点。因其侵袭性生长,目前采取的手术联合放化疗的综合治疗方案疗效欠佳。如何靶向显像和治疗胶质瘤成为研究的重点。近年来,大量研究表明,作为氯毒素的类似物,东亚钳蝎氯毒素能特异性地结合神经胶质瘤细胞表达的氯离子通道和基质金属蛋白酶2,从而抑制胶质瘤细胞的侵润生长和迁移。以东亚钳蝎氯毒素为配体的生物结合物在胶质瘤靶向显像和治疗中的研究越来越多。笔者将全面介绍东亚钳蝎氯毒素的来源、化学结构、作用机制及其在胶质瘤靶向显像与治疗中的应用研究进展,并总结其优势及在未来研究中所面临的挑战。     

靶向VEGFR2光声/超声双模态造影剂的制备及体外寻靶实验研究

目的制备一种特异性靶向新生血管内皮细胞的光声/超声双模态造影剂,探讨其体外寻靶能力及双模态显影效果。方法采用多步乳化法制备载有印度墨水和液态氟碳的高分子造影剂,用碳二亚胺法将造影剂与抗血管内皮生长因子受体2(VEGFR2)单克隆抗体相偶联,制备出靶向VEGFR2高分子造影剂(Vi-PFH-PLGA)。检测该造影剂的一般特性、体外寻靶能力及双模态显影效果,并与非靶向高分子造影剂进行比较。结果所制备的靶向高分子造影剂的平均粒径为(565.5±15.6)nm,间接免疫荧光法观察到抗体成功的连接到造影剂表面,流式细胞仪测得抗体微球连接率为99.72%,体外寻靶能力实验显示较多的靶向造影剂呈花环状牢固的聚集在人脐静脉内皮细胞HUVEC表面,而非靶向组和抗体干预组未见造影剂与HUVEC的特异性结合。体外光声/超声显影实验显示,经脉冲激光辐照后,靶向造影剂组可检测到明显的光声信号和超声信号,与非靶向造影剂相比差异无统计学意义(P均0.05)。结论成功制备出靶向VEGFR2的光声/超声双模态造影剂,该造影剂在体外与HUVEC细胞具有较强的靶向结合能力且具备较好的光声/超声双模态显影效果。     

Novel treatment of ovarian cancer cell lines with Imatinib mesylate combined with Paclitaxel and Carboplatin leads to receptor-mediated antiproliferative effects

Purpose  Imatinib is a small molecule inhibiting the tyrosine kinases bcr-abl, c-kit, PDGFR-α and PDGFR-β. Investigations were performed to screen ovarian cancer cell lines and tumor samples for target receptor expression. Effects of Imatinib on cell proliferation and apoptosis induction were measured with and without additional cytotoxic agents. Methods  Expression patterns of abl, c-kit, PDGFR-α and PDGFR-β (Imatinib targets) were studied in 5 cell lines and 111 tissue arrays by PCR and immunohistochemistry. Proliferation assays were performed with single agent Imatinib or combined with Paclitaxel and Carboplatin. Apoptosis was measured by DNA fragmentation. Results  All cell lines expressed abl and PDGFR-β. C-kit was only expressed in 2/5 cell lines and PDGFR-α in 4/5. Imatinib reduced cell growth and lead to pro-apoptotic changes. Combination of Carboplatin, Paclitaxel and Imatinib showed synergistic activity. Conclusions  Our results suggest that Imatinib may be useful for the specific treatment of ovarian cancer as an add-on to conventional chemotherapy. C. Mundhenke and M. T. Weigel contributed equally to this work.