Castellà E M, Ariza A, Ojanguren I, Mate J L, Roca X, Fernández-Vasalo A, Navas-Palacios J J
Department of Pathology, Hospital Germans Trias i Pujol, Barcelona, Spain.
Virchows Arch. 1996 Nov;429(4-5):191-5. doi: 10.1007/BF00198333.
Alternative splicing gives rise to numerous CD44 isoforms, some of which seem to have a role in tumour metastasis. Specifically, a variant form of CD44 with sequences encoded by exon v6 (CD44v6) confers metastatic potential when transfected into a nonmetastasizing cell line of rat pancreatic adenocarcinoma. This study has investigated standard CD44 (CD44s) and CD44v6 expression immunohistochemically in 6 samples of normal pancreatic tissue, 4 of tissue affected by chronic pancreatitis, and 24 of tissue from metastasizing and nonmetastasizing pancreatic adenocarcinomas. In addition, 18 samples from lymph node or visceral metastases were included in the study. CD44s was expressed in nonneoplastic tissue and in tissue from pancreatic adenocarcinomas. In contrast, CD44v6 was not detected in any of the normal tissue or chronic pancreatitis specimens, whereas 54% of pancreatic adenocarcinomas and 55% of metastases expressed this variant exon. Although it is not clear whether CD44 isoforms containing exon v6 play a part in malignant progression in the human exocrine pancreas, it seems plausible that the expression of multiple isoforms containing this and other variant exon confers a selective advantage on pancreatic adenocarcinoma.
可变剪接产生了众多CD44异构体，其中一些似乎在肿瘤转移中发挥作用。具体而言，一种具有外显子v6编码序列的CD44变异形式（CD44v6），当转染到大鼠胰腺腺癌的非转移细胞系中时赋予了转移潜能。本研究采用免疫组织化学方法检测了6份正常胰腺组织样本、4份受慢性胰腺炎影响的组织样本以及24份转移和非转移胰腺腺癌组织样本中标准CD44（CD44s）和CD44v6的表达。此外，该研究还纳入了18份来自淋巴结或内脏转移灶的样本。CD44s在非肿瘤组织和胰腺腺癌组织中均有表达。相比之下，在任何正常组织或慢性胰腺炎标本中均未检测到CD44v6，而54%的胰腺腺癌和55%的转移灶表达了该变异外显子。虽然尚不清楚含外显子v6的CD44异构体是否在人类外分泌胰腺的恶性进展中起作用，但似乎含有该外显子和其他变异外显子的多种异构体的表达赋予了胰腺腺癌选择性优势这一观点是合理的。
