Detection of tumor circulating cells by cytokeratin-20 in the blood of patients with granulosa cell tumors.
OBJECTIVE
Cytokeratins (CKs) are constituents of the intermediate filaments of epithelial cells which are expressed in various combinations, depending on the epithelial type and the degree of differentiation. Using the reverse transcriptase-polymerase chain reaction (RT-PCR) technique, we recently demonstrated that cytokeratin-20 (CK-20), the most recently discovered cytokeratin, is expressed in endometrial carcinoma tumors, in blood, and in lymph nodes with micrometastases of patients treated for endometrial carcinomas. However, CK-20 expression could not be demonstrated in the endometrium of patients with benign diseases, in peripheral blood, in lymph nodes of healthy subjects, or in normal blood cells. The aim of this study was to examine whether CK-20 expression in blood can be used as a biomarker for the detection of the dissemination of malignant cells in patients treated for granulosa cell tumors (GCTs).


METHODS
In this study, we used RT-PCR to determine the expression of CK-20 in the following groups: (i) blood of patients (n = 14) treated for GCTs, (ii) GCT samples (n = 4); (iii) lymph nodes (n = 2) of patients treated for GCTs; (iv) blood from subjects with benign sex-cord-stromal tumors (n = 2); (v) normal ovaries of two menstruating women (n = 4); (vi) tumor specimens of epithelial ovarian carcinomas (EOCs) (n = 14); and (vii) blood samples (n = 18) and lymph nodes (n = 11) of healthy women.


RESULTS
In Group I, CK-20 was positive in the blood in 86% (12/14) of the patients. In Group II, CK-20 was positive in 100% (4/4) of the GCT samples. In Group III, CK-20 was positive in 100% (2/2) of the lymph nodes examined. In Groups IV and V, CK-20 was negative in 100% (2/2) of the blood samples and in the normal ovarian specimens (4/4) that were examined. In Group VI, CK-20 was positive in 14% (2/14) of nonmucinous EOCs. In Group VII, CK-20 was negative in 100% (18/18) of blood and in (11/11) lymph node specimens (specificity 100%).


CONCLUSIONS
These results indicate that RT-PCR of CK-20, because of its high sensitivity and specificity, is a potential biomarker for detecting metastases in blood and in micrometastases in lymph nodes of patients treated for GCTs.
Altaras
Marco M
MM
Gynecologic Oncology Unit, Department of Obstetrics and Gynecology, Sapir Medical Center, Kfar Saba 44281, Israel. altaras@clalit.org.il
Klein
Ami
A
Zemer
Ruth
R
Zimlichman
Shulamit
S
Bernheim
Joelle
J
Fishman
Ami
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006106:Granulosa Cell Tumor / Q000097:blood* / Q000473:pathology; D006801:Humans; D007381:Intermediate Filament Proteins / Q000096:biosynthesis / Q000097:blood*; D053554:Keratin-20; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000097:blood* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction
D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; D053554:Keratin-20