miRNA-132通过Hedgehog信号通路对肝癌细胞凋亡的作用机制

目的：探究miRNA-132（miR-132）通过Hedgehog 信号通路对肝细胞癌细胞凋亡的机制。方法：用miR- 132 类似物转染人肝癌HepG2 细胞,将样本分为空白组（ 无转染HepG2）、NC组（HepG2 转染miR-132-NC）、 YJ 组（HepG2 转染miR-132 mimic）。通过qRT-PCR 检测miR-132 在HepG2 细胞中的表达量,采用CCK-8 法、流 式细胞仪、Transwell 小室、免疫印迹检测细胞增殖、凋亡、侵袭能力以及Shh 蛋白表达。结果：PCR检测结果显示, 3 组对比,YJ 组HepG2 细胞中miR-132 表达量最高,说明转染成功;CCK-8 检测结果显示,YJ 组HepG2 细胞增 殖数量最低,空白组HepG2 细胞的增殖与NC组相似,皆高于YJ 组;流式细胞检测结果显示,与NC组及空白组 比较,YJ 组HepG2 细胞凋亡数量最多 ;Transwell 小室检测结果显示, YJ 组细胞侵袭数量与空白组和NC组相比 明显降低,空白组细胞侵袭数量与NC组相比数据接近;免疫印迹检测结果显示,YJ 组Shh 蛋白相对表达量与空 白组和NC组比明显降低。结论：过表达miR-132 降低Hedgehog 信号通路,可促进人肝癌HepG2 细胞凋亡作用。     

Dbx2 exhibits a tumor-promoting function in hepatocellular carcinoma cell lines via regulating Shh-Gli1 signaling

BACKGROUND Hepatocellular carcinoma(HCC)is the fifth most common cancer worldwide.HCC patients suffer from a high mortality-to-incidence ratio and low cure rate since we still have no specific and effective treatment.Although tremendous advances have been made in the investigation of HCC,the specific mechanisms of the progression of this disease are still only partially established.Hence,more research is needed to elucidate the underlying potential mechanisms to develop effective strategies for HCC.AIM To determine the role of developing brain homeobox 2(Dbx2)gene in promoting the development of HCC.METHODS Dbx2 expression in clinical specimens and HCC cell lines was detected by Western blot(WB)and immunohistochemistry.Gain and loss of Dbx2 function assays were performed in vitro and in vivo.Cell viability assays were used to investigate cell growth,flow cytometry was employed to assess cell cycle and apoptosis,and trans-well assays were conducted to evaluate cell migration,invasion,and metastasis.The expression of key molecules in the sonic hedgehog(Shh)signaling was determined by WB.RESULTS Compared to matched adjacent non-tumorous tissues,Dbx2 was overexpressed in 5 HCC cell lines and 76 surgically resected HCC tissues.Dbx2 overexpression was correlated with large tumor size.Both gain and loss of function assays indicated that Dbx2 promoted HCC cell proliferation by facilitating the transition from G1 to S phase,attenuating apoptosis and promoted HCC proliferation,migration,and invasion in vitro and in vivo.Mechanistically,Dbx2 modulated Shh signaling by enhancing FTCH1 and GLi1 expression in HCC cells that overexpressed Dbx2,which was reversed in HCC cells with Dbx2 knockdown.CONCLUSION Our results indicate that Dbx2 is significantly upregulated in HCC tissues and plays significant roles in proliferation and metastasis of HCC cells by activating the Shh pathway.     

Ptch和Smo在舌鳞状细胞癌Tca8113细胞中的表达及其意义

目的:研究Hedgehog(Hh)信号通路相关因子Ptch和Smo在舌鳞状细胞癌Tca8113细胞株中的表达及其意义。方法:Hh信号通路抑制剂Cyclopamine处理Tca8113细胞后,采用MTT实验检测细胞增殖抑制率,再利用RT-PCR法和Western-Blot方法检测 Ptch和Smo的mRNA和蛋白表达情况。结果:Cyclopamine对Tca8113细胞增殖具有抑制作用。加药后的不同时间段中,显示Ptch、Smo的mRNA和蛋白在Cyclopamine药物组中的表达低于对照组。Smo的mRNA和蛋白分别在加药后24 h、72 h中的表达随着药物浓度增高而降低。结论:Cyclopamine可以抑制Tca8113细胞的生长,降低Smo mRNA和蛋白的表达,Hh信号通路可能在舌癌的发生、发展中起重要作用。[关键词] Hh信号通路 Tca8113细胞 Cyclopamine Ptch Smo     

Sonic Hedgehog在血管新生中的作用

Sonic Hedgehog介导的信号传导通路是血管生成中一个重要调节环节,可调控血管直径加粗、变长和分叉,影响基质细胞分泌众多的血管新生因子以及动脉血管的发生。Sonic Hedgehog可能通过3种机制(COUP-TF Ⅱ、SHH／GLI／SMO、P13K通路)调控血管生成,并有望成为血管新生研究的新靶向因子。     

Systemic therapy for disseminated basal cell carcinoma: an uncommon manifestation of a common cancer

While basal cell carcinoma (BCC) is the most common human malignancy, distant metastases from this are rare. Current therapy for disseminated BCC is based on anecdotal reports in the absence of clinical trials to guide management. For many years, platinum based cytotoxic chemotherapy was the mainstay of treatment. Advances in the understanding of the biology of BCC have led to the development of targeted therapies (e.g. inhibitors of the hedgehog and the epidermal growth factor receptor pathways) that are currently being investigated in this disease. This review summarizes the available data on the epidemiology and management of disseminated BCC.     

Hedgehog signaling in the posterior region of the mouse gastrula suggests manifold roles in the fetal-umbilical connection and posterior morphogenesis

Although many fetal birth defects, particularly those of the body wall and gut, are associated with abnormalities of the umbilical cord, the developmental relationship between these structures is largely obscure. Recently, genetic analysis of mid‐gestation mouse embryos revealed that defects in Hedgehog signaling led to omphalocoele, or failure of the body wall to close at the umbilical ring (Matsumaru et al. [ 2011 ] PLos One 6:e16260). However, systematic spatiotemporal localization of Hedgehog signaling in the allantois, or umbilical precursor tissue, and the surrounding regions has not been documented. Here, a combination of reagents, including the Ptc1:lacZ and Runx1:lacZ reporter mice, immunohistochemistry for Smoothened (Smo), Sonic Hedgehog (Shh), and Indian hedgehog (Ihh), and detailed PECAM‐1/Flk‐1/Runx‐1 analysis, revealed robust Hedgehog signaling in previously undocumented posterior sites over an extended period of time (～7.0–9.75 dpc). These included the recently described proximal walls of the allantois (Ventral and Dorsal Cuboidal Mesothelia; VCM and DCM, respectively); the ventral embryonic surface continuous with them; hemogenic arterial endothelia; hematopoietic cells; the hindgut; ventral ectodermal ridge (VER); chorionic ectoderm; and the intraplacental yolk sac (IPY), which appeared to be a site of placental hematopoiesis. This map of Hedgehog signaling in the posterior region of the mouse conceptus will provide a valuable foundation upon which to elucidate the origin of many posterior midline abnormalities, especially those of the umbilical cord and associated fetal defects. Developmental Dynamics 240:2175–2193, 2011. © 2011 Wiley‐Liss, Inc.     

Hedgehog signaling is required for formation of the notochord sheath and patterning of nuclei pulposi within the intervertebral discs

The vertebrae notochord is a transient rod-like structure that produces secreted factors that are responsible for patterning surrounding tissues. During later mouse embryogenesis, the notochord gives rise to the middle part of the intervertebral disc, called the nucleus pulposus. Currently, very little is known about the molecular mechanisms responsible for forming the intervertebral discs. Here we demonstrate that hedgehog signaling is required for formation of the intervertebral discs. Removal of hedgehog signaling in the notochord and nearby floorplate resulted in the formation of an aberrant notochord sheath that normally surrounds this structure. In the absence of the notochord sheath, small nuclei pulposi were formed, with most notochord cells dispersed throughout the vertebral bodies during embryogenesis. Our data suggest that the formation of the notochord sheath requires hedgehog signaling and that the sheath is essential for maintaining the rod-like structure of the notochord during early embryonic development. As notochord cells form nuclei pulposi, we propose that the notochord sheath functions as a "wrapper" around the notochord to constrain these cells along the vertebral column.