5-ALA在胶质瘤光动力治疗应用的进展

胶质瘤作为常见的颅内恶性肿瘤,传统的手术与放疗化疗联合的治疗方法难以取得令人满意的治疗效果。光动力治疗作为治疗恶性肿瘤有效的辅助方法,在胶质瘤治疗中得到广泛应用。5-氨基乙酰丙酸(5-aminolevulinic acid,5-ALA)是在光动力治疗中应用最多的光敏剂前体物质。多年来针对5-氨基乙酰丙酸(5-aminolevulinic acid,5-ALA)在胶质瘤光动力治疗中的研究主要集中在如何增强光动力效应,这也是许多神经外科医生的兴趣所在。本文结合相关文献,对5-ALA在胶质瘤光动力治疗的研究进展及未来在此领域面临的挑战进行了综述。     

光感应化合物在光控治疗中的应用

综述了光感应化合物在以光为手段治疗疾病方面的研究和应用.介绍了光动力治疗及卟啉类和酞菁类化合物在光动力治疗中的应用现状,讨论了光动力作用中活性氧的产生机理,着重介绍了含偶氮苯基团的光感应化合物和含其它光感应材料的脂质体在光控治疗中的应用和发展,阐述了光化学内化的研究进展,并展望了光感应脂质体在光控治疗中潜在的应用价值.     

光动力疗法在治疗消化道肿瘤中的应用与研究进展

光动力疗法是目前临床上出现的一种新型治疗肿瘤的方法,利用光敏剂吸收可见-近红外光并在组织氧的参与下发生光化学反应,产生活性氧物质进而诱导肿瘤细胞凋亡或坏死。光动力疗法对肿瘤侵袭性低,具有较高的选择性和良好的患者依从性,因此被广泛用于各种消化道恶性肿瘤的姑息性治疗和挽救性治疗。本文对近年来国内外应用光动力疗法治疗消化道肿瘤的文献进行综述,对所报道的疾病类型、治疗病例数、光敏剂和光源、疗效和安全性等信息进行分类整理,并对所面临的挑战和近期的研究进展进行了汇总,以期全面和客观地了解光动力疗法在治疗消化道肿瘤中的应用和研究进展,探讨目前的新应用及存在的问题和可能的发展方向。     

聚合物纳米粒在肿瘤光动力治疗中的研究进展

光动力治疗创伤小,在恶性肿瘤治疗方面的应用已经得到了临床认可。治疗过程中需要给予光敏剂,在光照下产生分子氧对肿瘤细胞产生杀伤作用。但是,大多数光敏剂缺乏对肿瘤细胞的特异性,其在肿瘤中的富集主要与细胞高代谢有关,并且在水相媒介中溶解度比较差。纳米技术应用于光动力治疗提供了一种有效地体内运输光敏剂的方式。目前,聚合物纳米粒与光动力药物传递的研究越来越多,光敏剂通过纳米粒的运输为弥补光动力治疗的不足提供了可能,这是因为纳米载体可以将治疗浓度的光敏剂运送到肿瘤细胞而不造成非靶向组织的副损伤。本文将介绍对肿瘤光动力治疗中具有特异性的聚合物纳米粒的种类及在临床中的应用情况,为肿瘤靶向治疗提供新思路。     

光动力技术治疗胃癌的进展及展望

近年来应用光动力技术治疗胃癌取得了可喜的进步,它对各个时期的胃癌均有比较满意的临床效果。本文通过对国内外近年来用光动力技术治疗胃癌方面的文献进行综述,系统阐述光动力运用于胃癌治疗这一项技术的原理、机制,光敏剂、光源及临床效果等方面,并总结了这项技术在治疗胃癌方面的优点和相关问题。     

结直肠癌的光动力治疗进展

结直肠癌是消化系统最常见的恶性肿瘤之一,且发病率逐年上升,但其治疗往往仅限于手术、放疗、化疗等传统方法。近年来,光动力疗法在结直肠癌治疗中取得了满意效果。本文对近年来国内外应用光动力疗法治疗结直肠癌的文献进行综述,系统阐述这一治疗方法的起源与发展、作用原理及机制、光敏剂与光源的选择、临床效果、不良反应、制约发展因素及可能解决办法。希望通过本文,为临床医师治疗结直肠癌提供一种新的治疗手段。     

光动力疗法联合声动力疗法在抗肿瘤方面的研究进展

光动力疗法是一种使用光敏药物和激光活化治疗肿瘤疾病的方法。用特定波长的光辐照肿瘤部位,能使选择性聚集在肿瘤组织的光敏药物活化,引发光化学反应破坏肿瘤。然而,光动力疗法在临床上的应用却一直存在治疗深度受限的问题。本文分析了光动力疗法在临床应用中的局限性,并指出光动力疗法联合声动力疗法是一种可以克服光动力疗法治疗深度局限性的新型非侵入性治疗方法。     

光动力治疗与抗肿瘤免疫

光动力治疗是通过特定波长的光激发光敏剂产生活性氧反应物实现对微生物和肿瘤细胞的杀伤。由于光动力治疗的疗效确切,副作用小,并易于与其他治疗方式联用,因而已成为临床肿瘤治疗的新手段。近年来,抗肿瘤免疫的基础研究和临床应用获得了重大进展。研究表明,光动力治疗与抗肿瘤免疫治疗的联合应用具有显著的协同抗肿瘤效应。本文综述了光动力治疗研究进展及其在抗肿瘤免疫治疗的应用,讨论了其面临的障碍及发展前景。     

光动力治疗在各类恶性肿瘤病人姑息治疗中的应用探讨

光动力治疗(photodynamic therapy,PDT)是近二十年来新兴的肿瘤治疗方法,与肿瘤传统手术、化疗和放疗方法相比,能选择性地消灭局部的原发和复发肿瘤,而不伤及正常组织。大多数肿瘤出现临床症状时,已是肿瘤晚期,丧失了肿瘤治疗的最佳时机。光动力治疗作为新兴的肿瘤治疗技术,能够以较小创伤为代价改善患者的生活质量,并提高患者生存时间,有望成为恶性肿瘤姑息性治疗的首选。     

光动力治疗光源的研究新进展

光动力疗法(PDT)是一种联合利用治疗光源、光敏剂和氧分子,选择性治疗恶性肿瘤和良性疾病的精准靶向疗法。光源作为PDT治疗的关键要素之一,其发光波长、照光方式和剂量直接影响疗效。本文详细介绍了太阳光、近红外光、X射线、在体发光和发光二极管等5种PDT光源的研究新进展,并分析了这五种治疗光源在生物组织穿透深度上的不同特性以及所存在的不足。随后,重点讨论了以提高PDT治疗精度为目标的体表照光和体内照光等两种个性化照光模式。研发操作简便、价格低廉、性能优异的新型PDT光源是未来的发展方向。     

黏蛋白阿克曼菌辅助治疗恶性肿瘤的研究进展

恶性肿瘤是威胁人类健康的全球重大公共卫生问题,多种方法联合,特别是以靶向治疗联合免疫治疗为主的治疗手段,在一定程度延缓了恶性肿瘤的发展,提高了患者的近期生存率,但这些治疗方法并不能覆盖所有患者,远期疗效仍然有限。因此,如何提高患者的生存质量和远期生存率,降低死亡率,成为当前亟待解决的关键问题。近年来越来越多的研究显示肠道微生物的分布与恶性肿瘤的发生、发展密切相关,或可成为治疗恶性肿瘤的新辅助方法,特别是嗜黏蛋白阿克曼菌（Akkermansia muciniphila）的报道较多,然而,关于该菌在恶性肿瘤辅助治疗中安全性和有效性的文献报道尚不多见。因此,本文旨在通过收集近年来嗜黏蛋白阿克曼菌在恶性肿瘤方面的文献,将其研究成果和应用结果进行归纳、分析,以期为临床综合治疗提供一定的药物选择。     

肿瘤干细胞对恶性肿瘤辅助治疗的影响

放化疗是目前恶性肿瘤治疗的重要手段,但是迄今为止,除了手术以外,几乎没有能单独根治恶性肿瘤的治疗方法,甚至一些恶性肿瘤在手术、化疗或放疗后会出现再生和侵袭能力增强,被称为恶性肿瘤治疗后再增殖,这可能是恶性肿瘤治疗失败的主要原因,其主要机制可能是肿瘤干细胞(cancer stem cells,CSCs)对放化疗的耐受,以及放化疗导致肿瘤细胞的上皮细胞间质化,继而提高了肿瘤侵袭性。该文将从CSCs的角度重新探讨放化疗等辅助治疗对恶性肿瘤的影响。     

肿瘤类器官在药物筛选和个性化用药中的研究进展*

恶性肿瘤是影响人类生命健康的重大疾病之一,药物治疗是常见的治疗手段。近年来,“精准治疗”已经成为肿瘤治疗的趋势。要实现对恶性肿瘤有效、精准的药物治疗,药物筛选模型至关重要。肿瘤类器官是近年来新兴的一种三维细胞模型,具有经长期传代还保留亲本肿瘤的特征和异质性、培养成功率高、周期短和能够高通量筛选药物等优点,已被用于药物筛选、预测患者对治疗的反应以及为个性化用药提供指导等。重点介绍了肿瘤类器官在药物筛选及个性化用药中的研究进展和面临的挑战。     

Tumors in nonhuman primates: observations during a six-year period in the Yerkes primate center colony

Tumors were observed in nine of 1,066 nonhuman primates submitted for postmortem examination during a six-year period at the Yerkes Primate Center. Six of these animals had malignant tumors, and one animal had two primary malignancies. Nonhuman primates with tumors included rhesus, squirrel, and pigtail monkeys. Tumors observed included a sarcoma of the stomach, a sarcoma of the thigh, a malignant lymphoma, a glioblastoma of the cerebrum, two renal cell carcinomas, a carcinoma of the endometrium, and three uterine leiomyomas. Two monkeys in the colony presently have malignant tumors, one a testicular seminoma, and the other an abdominal adenocarcinoma, probably of ovarian origin. Electron microscopy revealed virus-like particles in specimens from the thigh sarcoma. The only tumors observed in any of the great ape species during this period have been two surgically removed benign tumors in chimpanzees, a subcutaneous lipoma and a hemangioma of the skin.     

MEDIASTINAL TUMORS OF THYMIC ORIGIN

Twenty-one cases of mediastinal tumors of thymic origin are presented. Five of these were benign and 16 malignant.Surgical excision is proposed as the treatment of choice for the encapsulated benign tumors or for malignant tumors of limited extent. When surgical excision is not feasible, adequate roentgen therapy amounting to 5,000 to 6,000 r calculated tumor dose may eradicate or control the tumor.No correlation between the histological pattern of the tumor and the survival rate or radiation response could be demonstrated in this small series.     

肿瘤基因治疗的研究进展

基因治疗作为一种新的治疗手段,给许多绝症患者带来希望。基因治疗的范围已从最初的单基因疾病扩展到恶性肿瘤、心脑血管及自身免疫等诸多领域,其中以恶性肿瘤为主要对象。本文综述了肿瘤基因治疗中的基因转移方法、基因治疗策略、导向基因治疗及其在应用上的问题与展望。     

Ovarian carcinoma of low malignant potential treated at the 1(st) Department of Obstetrics and Gynecology Semmelweis University Faculty of Medicine,between 1990 and 2000

The authors analyzed the epidemiologic and histological characteristics and the management of ovarian carcinoma of low malignant potential (LMP) at a university hospital between 1990 and 2000. The authors carried out a retrospective study reviewing hospital charts. Based on the records experience with 29 such tumors is peresented. Of these 20 (74%) were of the serous variety, 7 (26%) were mucinous. LMP tumors accounted for 16% of proliferating epithelial ovarian tumors. They occured at a mean age of 45 years. The LMP tumors were bilateral in 12% of the cases. The majority of patients (87%) with LMP tumors presented with early stage disease. Tumor markers such as CA-125 were not always elevated as in invasive ovarian carcinoma. Laboratory investigations have not demonstrated that these tumors represent an intermediate step between benign ovarian tumors and carcinoma. The recommended therapy is surgical, consisting of total abdominal hysterectomy, bilateral salpingo-oophorectomy, peritoneal washings, and tumor debulking. Conservative surgery consisting of unilateral salpingo-oophorectomy is considered to be an appropriate treatment for young women with early stage LMP ovarian tumors who wish to retain their fertility potential. 50 percent of women who underwent conservative surgery subsequently conceived in this study. There were no recurrences in the study group, so the authors conclude that the long term outcome of LMP tumors is extremely favorable.     

Tumor heterogeneity: morphological, molecular and clinical implications

Malignant tumors are characterized by their great heterogeneity and variability. There are hundreds of different types of malignant tumors that harbour many oncogenic alterations. The tumor heterogeneity has important morphological, molecular and clinical implications. Except for some hematopoietic and lymphoproliferative processes and small cell infant tumors, there are not specific molecular alterations for most human tumors. In this review we summarize the most important aspects of carcinogenesis and chemoradiosensitivity of malignant cells. In this regard, some oncogenes such as neu, ras and bcl-2 have been associated with cellular resistance to treatment with anticancer agents. The knowledge of oncogenic alterations involved in each tumor can be important to correlate the morphological features, the genetic background, the prognosis and the clinical response to treatment with anticancer agents. Based on the molecular background of the tumor there are new cancer gene therapy protocols. For example using adenovirus Ela in tumors with overexpression of neu oncogene, inhibitors of tyrosine kinase specific for the PDGF receptor in glioma, inhibitors of farnesil transferase to prevent ras activity in tumors with mutations in the ras gene.     

131I]metaiodobenzylguanidine therapy in paraganglioma.

Our experience with [131I]metaiodobenzylguanidine (131I-MIBG) therapy in a 10 year old boy is reported. At disease onset, in May 1988, this boy presented a large mass in the upper left abdominal quadrant, which was resected with a histopathological diagnosis of extra-adrenal malignant pheochromocytoma (paraganglioma). He subsequently underwent two further surgical resections and chemotherapy. When 131I-MIBG therapy was started, in June 1990, skeletal and abdominal metastases were present. These localizations were revealed by 131I-MIBG scans and confirmed by x-ray examination. At present 6 courses of therapy have been performed with a cumulative activity of 29.6 GBq. Side-effects have been limited to vomiting and mild thrombocytopenia, lasting 2 weeks during the second course of therapy. After 15 months of therapy, a progressive reduction of MIBG uptake, coupled with a stabilization of the lythic lesions, has been observed.     

Cell heterogeneity and subpopulations in solid tumors characterized by simultaneous immunophenotyping and DNA content analysis

BACKGROUND: Heterogeneity in human malignant tumors is a well-described phenomenon and of interest with regard to subpopulations with differences in clonality, metastatic potential, and response to therapy under different treatment regimes. The aim of this study was the simultaneous characterization of surface markers and DNA content of solid tumors to identify tumor cell subpopulations and to study the association between the expression of antigens and DNA content. METHODS: In the present study, six different malignant tumors grown as xenografts in nude mice were characterized by five-parameter flow cytometry. Immunophenotyping was performed using a variety of direct fluorescence-conjugated antibodies. In all cases, simultaneous detection of DNA content was done after staining with 7-aminoactinomycin D. RESULTS: Tumor cells were characterized by light scatter properties, antigen expression, and DNA content. Tumor cell heterogeneity, subpopulations, and DNA content-dependent antigen expression were identified. CONCLUSIONS: This method offers the possibility of characterizing solid tumors according to their immunophenotype and DNA content. The results obtained can be used to identify changes in immunophenotypic and DNA profiles of tumor cell populations before and after therapy and might be useful to define parameters predictive for response to therapy.