Chyczewski L, Nikliński J, Chyczewska E, Laudański J, Furman M
Department of Pathomorphology, Medical Academy of Białystok.
Rocz Akad Med Bialymst. 1997;42 Suppl 1:162-72.
Cytokeratins (CK) are one of the main families of intermediate filaments which make up the cytoskeleton. CK19 is strongly expressed by normal simple bronchial and respiratory epithelium as well as by their malignant counterpart. Although CK19 is a part of the cytoskeleton, a soluble fragment of this polypeptide can be released and assayed in the blood as CYFRA 21-1, new sensitive and valuable marker of non small cell lung cancer. In some cases, however, discrepancies between the serum level of CYFRA 21-1 and presence of tumor and its histological type have been observed. We studied immunohistochemically tissue localization of CK19 in tumors and non invaded lung parenchyma in a series of 34 patients surgically treated due to lung cancer. CK 19 was detected in cancer cells as well as in non neoplastic epithelium covering bronchial tree and alveolar surfaces. We found a different expression of CK19 in different histological type of tumors. The most intensive expression revealed squamous cell carcinomas and adenocarcinomas. Small cell cancer revealed poor expression of CK19. In non invaded parts of the resected lungs we found the strong expression of CK19 in the cytoplasm of regenerative II type pneumocytes occurring in large quantity in the cases of interstitial lung fibrosis concomitant with some tumors. We suggest it may be a cause of unexpectedly elevated serum levels of CYFRA 19-21 in some not oncological patients or patients with small cell lung cancer.
细胞角蛋白（CK）是构成细胞骨架的中间丝主要家族之一。CK19在正常的单层支气管和呼吸道上皮及其恶性对应物中强烈表达。尽管CK19是细胞骨架的一部分，但该多肽的可溶性片段可以释放到血液中并作为CYFRA 21-1进行检测，CYFRA 21-1是一种新的非小细胞肺癌敏感且有价值的标志物。然而，在某些情况下，已观察到CYFRA 21-1的血清水平与肿瘤的存在及其组织学类型之间存在差异。我们对34例因肺癌接受手术治疗的患者进行了免疫组织化学研究，以确定CK19在肿瘤组织和未受侵犯的肺实质中的定位。在癌细胞以及覆盖支气管树和肺泡表面的非肿瘤上皮中检测到CK 19。我们发现在不同组织学类型的肿瘤中CK19的表达不同。鳞状细胞癌和腺癌的表达最为强烈。小细胞癌中CK19的表达较弱。在切除肺的未受侵犯部分，我们发现再生II型肺细胞的细胞质中CK19表达强烈，在一些伴有肿瘤的间质性肺纤维化病例中，再生II型肺细胞大量存在。我们认为这可能是一些非肿瘤患者或小细胞肺癌患者血清CYFRA 19-21水平意外升高的原因。
