Heikinheimo K, Sandberg M, Happonen R P, Virtanen I, Bosch F X
Department of Pathology, University of Helsinki, Finland.
Lab Invest. 1991 Dec;65(6):688-701.
In situ and Northern hybridization was carried out to study cytokeratin (Ck) 1, 4, 8, 18, and 19 and vimentin (Vim) gene expression in 13- to 24-week-old human fetal tooth germs, including overlying oral epithelium and odontogenic tumors (N = 6) of epithelial (ameloblastoma) and epithelial-ectomesenchymal (ameloblastic fibroma) origin. The results were compared with immunocytochemistry using monoclonal antibodies. A relatively strong expression of simple epithelial Ck 19 mRNA, together with low, but significant expression of Ck 8 and 18 mRNAs, was demonstrated in all normal and neoplastic odontogenic epithelia studied. Transcripts for squamous differentiation marker, Ck 4, and for terminal differentiation marker, Ck 1, were detected suprabasally in the fetal oral epithelium, focally in the dental lamina but not in the enamel organ. Ck 4 mRNA was expressed variably in most odontogenic tumors studied, whereas Ck 1 mRNA was detected in one ameloblastoma only. Vim mRNA was not found in the fetal oral epithelia, dental lamina or the enamel organ, but a distinct immunoreactivity with monoclonal antibodies to Vim was seen in the stellate reticulum cells of the enamel organ. The epithelium of most ameloblastomas showed a focal Vim mRNA and polypeptide expression. In addition to Vim, the neoplastic ectomesenchymal cells of ameloblastic fibroma coexpressed low amounts of simple epithelial Cks 8, 18, and 19. The results indicate that the differentiation and cytoskeletal gene expression programs of odontogenic epithelia upon neoplastic transformation are not fully retained. Most ameloblastomas and ameloblastic fibromas show differentiation parameters reminiscent of dental lamina. Ameloblastomas seem to form a heterogenous group of tumors, which may originate from odontogenic epithelial cells at various differentiation levels. The origin of ameloblastic fibroma is more closely related to the tooth germ proper.
进行原位杂交和Northern杂交，以研究13至24周龄人胎儿牙胚中细胞角蛋白（Ck）1、4、8、18和19以及波形蛋白（Vim）基因的表达，包括覆盖的口腔上皮以及上皮性（成釉细胞瘤）和上皮-外间充质（成釉细胞纤维瘤）来源的牙源性肿瘤（N = 6）。将结果与使用单克隆抗体的免疫细胞化学结果进行比较。在所研究的所有正常和肿瘤性牙源性上皮中，均显示出简单上皮Ck 19 mRNA的相对强表达，以及Ck 8和18 mRNA的低但显著表达。鳞状分化标志物Ck 4和终末分化标志物Ck 1的转录本在胎儿口腔上皮的基底上层被检测到，在牙板中呈局灶性表达，但在成釉器中未检测到。Ck 4 mRNA在大多数所研究的牙源性肿瘤中表达各异，而Ck 1 mRNA仅在一例成釉细胞瘤中被检测到。在胎儿口腔上皮、牙板或成釉器中未发现Vim mRNA，但在成釉器的星网状细胞中可见与Vim单克隆抗体的明显免疫反应性。大多数成釉细胞瘤的上皮显示局灶性Vim mRNA和多肽表达。除Vim外，成釉细胞纤维瘤的肿瘤性外间充质细胞还共表达少量简单上皮Ck 8、18和19。结果表明，牙源性上皮在肿瘤转化后的分化和细胞骨架基因表达程序并未完全保留。大多数成釉细胞瘤和成釉细胞纤维瘤显示出类似于牙板的分化参数。成釉细胞瘤似乎形成了一组异质性肿瘤，其可能起源于不同分化水平的牙源性上皮细胞。成釉细胞纤维瘤的起源与牙胚本身关系更为密切。
