蛋白激酶CK2与Wnt信号转导途径

蛋白激酶CK2是一种真核中普遍存在的信使非依赖性丝/苏氨酸蛋白激酶,到目前为止,已发现其300多种底物,且数目还在增加,涉及到许多细胞生命过程,如从DNA复制、转录到细胞生长的信号转导、增殖、转化、细胞凋亡等。近来研究发现,CK2与Wnt信号转导途径存在着很大的联系,CK2可以与-βcatenin和dishevelled等Wnt信号蛋白相结合使它们磷酸化,正性调节Wnt信号转导途径。在肿瘤发生和早期胚胎发育过程中CK2增强Wnt信号转导,本文将从这两个方面加以综述。     

Genetics of neurofibromatosis 1-associated peripheral nerve sheath tumors

Neurofibromatosis 1, an inherited disorder that affects 1/3500 individuals worldwide, predisposes to the development of benign and malignant peripheral nerve sheath tumors. The disorder results from inactivation of one of the NFI genes. The second NFI gene is typically inactivated in Schwann cells during tumor formation. This article reviews the different types of genetic alterations in NFI in both constitutional and tumor tissues and genetic alterations of other genes that may affect tumorigenesis. These studies have provided insight into the genetic basis of both the variable expression of the disorder and of benign and malignant peripheral nerve sheath tumorigenesis.     

Homer1基因在人脑胶质瘤中的表达及意义

背景与目的：Homer1是一种与凋亡有关系的信号分子,其在人脑胶质瘤组织中的表达及作用尚未见报道。本研究旨在探讨Homer1在人脑胶质瘤中的表达及意义。方法：采用免疫组织化学化方法、Westernblot和实时荧光定量RT-PCR检测Homer1蛋白在3株人脑胶质瘤细胞系（U251、U87和SHG-44）、60例人脑胶质瘤组织和5例正常人脑组织中的表达水平。结果：（1）免疫组化结果显示：SHG-44和U87细胞中Homer1a染色呈强阳性,在U251细胞中弱阳性染色,肿瘤细胞的阳性染色都呈颗粒状分布于胞核、胞浆、胞膜及突起结构。3株细胞系中Homer1b/c染色呈阴性;Homer1a蛋白在人脑胶质瘤及正常人脑组织中的阳性率及免疫反应评分（IRS）分别为61.8%、4.35±3.99和1.2%、0.09±0.35（P均〈0.01）;Homer1a蛋白阳性率和IRS与脑胶质瘤Ⅰ～Ⅳ级病理级别间呈＂U＂型关系,其中Ⅰ和Ⅱ、Ⅲ级间差异非常显著（P〈0.01）,Ⅳ和Ⅱ、Ⅲ级间差异非常显著（P〈0.01）,Ⅰ和Ⅳ级、Ⅱ和Ⅲ级间差异显著（P〈0.05）,良、恶性脑胶质瘤之间Homer1a蛋白阳性率差异显著（P〈0.05）;Homer1b/c在人脑胶质瘤标本中不表达。（2）Homer1a蛋白及其mRNA在SHG-44和U87细胞中高表达,在U251细胞中低表达。Homer1b/c蛋白及其mRNA在3株细胞系中均无表达;Homer1a蛋白表达水平与Homer1 mRNA表达水平无明显差异（P〉0.05）;其他结果,mRNA表达情况和蛋白表达情况一致。结论：Homer1a蛋白和mRNA在人脑胶质瘤中有表达,并与脑胶质瘤的发生和发展密切相关;Homer1b/c不参与人脑胶质瘤的发生和发展。     

Th2 type inflammation promotes the gradual progression of HPV-infected cervical cells to cervical carcinoma

Objectives

To investigate the role of immunological parameters in tumorigenesis of cervical cancer in women infected with high risk human papillomavirus (hr-HPV), and determine whether key findings with human material can be recapitulated in the mouse TC1 carcinoma model which expresses hr-HPV epitopes.

Methods

Epithelial and lymphoid cells in cervical tissues were analyzed by immunohistochemistry and serum IL10 levels were determined by ELISA. Tumor draining lymph nodes were analyzed in the mouse TC1 model by flow cytometry.

Results

The mucosa was infiltrated by CD20 + and CD138 + cells already at cervical intraepithelial neoplasia 1 (CIN1) and infiltration increased in cervical intraepithelial neoplasia 3 (CIN3)/carcinoma in situ (CIS) and invasive cervical cancer (ICC), where it strongly correlated with infiltration by CD32B + and FoxP3 + lymphocytes. GATA3 + and T-bet + lymphoid cells were increased in ICC compared to normal, and expression in epithelial cells of the Th2 inflammation-promoting cytokine TSLP and of IDO1 was higher in CIN3/CIS and ICC. As a corollary, serum levels of IL10 were higher in women with CIN3/CIS or ICC than in normals. Finally we demonstrated in the mouse TC1 carcinoma, which expresses hr-HPV epitopes, an increase of cells expressing B cell or plasma cell markers or Fc receptors in tumor-draining than distal lymph nodes or spleen.

Conclusions

hr-HPV initiates a local Th2 inflammation at an early stage, involving antibody forming cells, and fosters an immunosuppressive microenvironment that aids tumor progression.