人乳头瘤病毒阴性的喉鳞癌细胞系的建立

目的 建立1株人乳头状瘤病毒（HPV）阴性的喉鳞状细胞癌细胞系,为体外研究喉癌提供理想的实验模型。方法 以逆转录聚合酶链反应（RT-PCR）证实为HPV阴性的高分化喉鳞癌手术切除标本接种于裸鼠皮下,取连续传代2次的裸鼠皮下移植瘤进行体外原代培养。通过光镜、电镜、生长曲线、细胞周期时相、软琼脂克隆实验、异种移植成瘤实验、角蛋白、癌胚抗原及HPV检测,对其生物学特性进行初步分析。结果 经裸鼠过渡所建立的高分化喉鳞癌细胞系（Lscc-02）目前已传至86代,细胞生长增殖稳定。该细胞系呈单层形式生长,群体倍增时间为39．1h。透射电镜下见胞质内典型的张力原纤维,细胞问以桥粒方式连接。染色体为人类核型,呈亚三倍体,众数分布在63～72。该细胞系具有恶性肿瘤细胞生长特征：软琼脂中形成克隆,裸鼠接种成瘤且形态结构、分化程度与原发瘤相似。免疫组织化学显示高分子量细胞角蛋白及癌胚抗原阳性,PCR显示HPV阴性。结论 建立Lscc-02细胞系为研究无HPV感染喉癌的发生、发展规律及HPV与喉癌演进的关系提供了有价值的体外模型。     

Immortalization of a cell line with neural stem cell characteristics derived from mouse embryo brain

Background

Neural stem cells (NSC) have been extensively used as a tool to investigate the mechanisms responsible for neural repair, and they have been also considered as the source for a series of promising replacement therapies in various neurodegenerative diseases. However, their use is limited by their relative rarity and anatomical localization, and also because, the methods for isolation and characterization are usually time consuming and have some technical limitations.

Results

In this study, we describe a resource and method for obtaining immortalized cells with NSC characteristics obtained from mouse brain embryo.

Conclusions

Because these cells can be maintained indefinitely in culture, they may constitute a permanent source of NSC that can be used for research studies on neural development and regeneration.

     

Inhibition of adhesion molecules by budesonide on a human epithelial cell line (lung carcinoma)

Inhaled corticosteroids in the treatment of asthma have been shown to produce marked reductions in the number of inflammatory cells (mainly mast cells and eosinophils) and their products at bronchial level (such as cytokines). Recently, it has been demonstrated that epithelial cells express ICAM-1/CD54 in allergic patients both during natural allergen exposure and after allergen challenge. We have previously demonstrated that deflazacort (a systemic steroid) reduces the expression of ICAM-1 on conjunctival epithelial cells. The present study aimed to evaluate the effects exerted by budesonide on adhesion molecule expression by a human epithelial cell line (lung carcinoma: DM) and on soluble ICAM-1. Budesonide was added at concentrations corresponding to 10⁻⁸, 10⁻⁷, and 10⁻⁶ mol/1 in cultured epithelial cells, either in the absence of any stimulus or in the presence of interferon-gamma (IFN-y) at 500 U/ml. After 24 h of incubation, cytofluorometric analysis was performed for ICAM-1 and CD29/VLAP1. The 24–h supernatants of the same cultures were collected and then evaluated for soluble ICAM-1 (sICAM-1). The results showed that budesonide inhibits ICAM-1 and CD29 basal expression on the cells studied (P<0.05): budesonide was effective in a dose-dependent manner. In addition, budesonide reduced surface ICAM-1 upregulation induced by IFN-γ at 500 U/ml (p<0.05). Finally, cell cultures with budesonide showed decreased levels of soluble ICAM-1 in basal condition, but not after IFN-γ stimulation.     

Isolation and identification of enteroviruses from faecal samples in a differentiated epithelial cell line (HRT-18) derived from human rectal carcinoma

A human rectal carcinoma-derived differentiated epithelial cell line, HRT-18, was inoculated with faecal samples in an attempt to grow coronavirus-like particles (CVLP), which are widely prevalent in human stools in southern India. While CVLP did not grow in this cell line, a variety of enteroviruses were isolated from 48 of the 114 stool samples from healthy controls and patients with diarrhoea. The results suggest that human gastrointestinal tumour-derived differentiated epithelial cells in continuous culture may be useful for the primary isolation of enteroviruses and merit further study.     

Establishment and characterization of a human colonic mucinous carcinoma cell line with predominant goblet-cell differentiation from liver metastasis

Many human colorectal adenocarcinoma cell lines have been developed. However, differentiated type colorectal cancer cell lines, particularly, the goblet-cell differentiated type, are scarce. In the present study a novel colorectal adenocarcinoma cell line (designated as COLM-6) with predominant goblet-cell differentiation was established from the rectal mucinous adenocarcinoma of a Japanese woman. COLM-6 cells grow in a typical epithelial monolayer in culture. They expressed epidermal growth factor (EGF) receptor and HER2 on their surface and accordingly, their growth was significantly stimulated by EGF, transforming growth factor (TGF)-alpha and heregulin. COLM-6 cells form tumor with typical mucinous adenocarcinomatous appearance in nude mice. Immunohistochemical analysis of these subcutaneous tumors demonstrated that COLM-6 cells strongly express MUC2 as a goblet-cell marker and Cdx2 in the nucleus. Some weakly express villin and carbonic anhydrase 1 as a columnar absorptive-cell marker as well. They were also positive for adenomatous polyposis coli (APC) cytoplasmically and expressed beta-catenin in their cytoplasm and cell membrane without nuclear accumulation. These results indicate that COLM-6 cell line has unique characteristics and may provide a useful tool to study the mechanism of growth and differentiation of colonic epithelium as well as the biological behavior of colorectal mucinous adenocarcinoma.     

Intrathyroidal epithelial thymoma/carcinoma showing thymus‐like differentiation; comparison with thymic lymphoepithelioma‐like carcinoma and a possibility of development from a multipotential stem cell

The purpose of our article is to describe the immunohistochemical findings of intrathyroidal epithelial thymoma/carcinoma showing thymus‐like differentiation (ITET/CASTLE) of the thyroid in detail, to clarify the difference between ITET/CASTLE and thymic lymphoepithelioma‐like carcinoma (LELC), and to discuss the pathogenesis of ITET/CASTLE. We immunohistochemically examined five ITET/CASTLE and eight LELC cases. All of ITET/CASTLE cases were strongly positive for CD5, P63, high‐molecular‐weight cytokeratin and B‐cell CLL/lymphoma‐2. Carcinoembryonic antigen‐positive carcinoma cells were found in four ITET/CASTLE cases. Neuroendocrine marker‐positive carcinoma cells were scattered in all cases. Immunohistochemical findings in thymic LELC were essentially similar to those in ITET/CASTLE, but the sensitivity was different. There is a possibility that ITET/CASTLE and thymic LELC are not the quite same disease entity. We think that ITET/CASTLE is derived from ectopic thymus, but not related to solid cell nests.