54474

KRT20

keratin 20, type I;KRT20;keratin 20, type I

cytokeratin 20|cytokeratin-20|keratin, type I cytoskeletal 20|keratin-20|protein IT

17q21.2

protein-coding

OBJECTIVE: To elucidate the significance of detecting cytokeratin gene (CK-20 mRNA) expression in metastatic lymph nodes of colon carcinoma patients. METHODS: The expression of CK-20 mRNA was detected in 342 lymph nodes by reverse transcription-polymerase chain reaction (RT-PCR) in 49 colon carcinoma patients. Its incidence was compared with that by routine pathologic examination. RESULTS: The positive rates of detecting metastasis in the lymph nodes were 21.9% by RT-PCR and 11.1% by routine pathologic examination. CONCLUSION: The detection of cancer metastasis in the lymph nodes in colon carcinoma is almost doubled (21.9% vs 11.1%) by CK-20 mRNA, which may provide a guiding significance in staging, treatment planning and prognosis in the prognostic estimation of colon carcinoma patients.

There are limited data regarding CDX2 expression in rectal carcinoma. The CK20/CK7 immunoprofile of colorectal adenocarcinoma has been described in studies, which have mostly lumped colonic and rectal tumors together. In this study, we investigated the diagnostic utility of immunohistochemical stains for CK7, CK20, and CDX2 in a series of rectal adenocarcinoma. Fifty-five specimens of rectal adenocarcinomas were retrieved and immunostained for CK7 (Dako-M7018), CK20 (NovoCastra NCL-L-CK20), and CDX2 (NovoCastra NCL-CDX2). Thirty cases of pancreatic adenocarcinoma and 15 cholangiocarcinomas were also studied as a comparison group. CK7 was expressed in 12/55 (22%) and CK20 in 48/55 (87%) cases of rectal adenocarcinoma. The CK7-/CK20+ immunophenotype was identified in 36/55 (65%), CK7+/CK20+ in 12/55 (22%), and CK7-/CK20- in 7/55 (13%) rectal adenocarcinoma. CDX2 showed moderate-strong positivity in all cases and was not related to tumor differentiation. Benign rectal mucosa was available in 37 cases and showed the following results: CK7-/CK20+ in 25/37 (67%), CK7+/CK20+ in 8/37 (22%) and CK7-/CK20- in 4/37 (11%) cases. In pancreatic adenocarcinomas and cholangiocarcinomas, 29/45 (64%) were CK7+/CK20+ and 16/45 (36%) were CK7+/CK20-. CDX2 was positive in only 3/45 (7%) of these cases; all were pancreatic adenocarcinomas. In conclusion, CK7 can be expressed in rectal adenocarcinoma, and should not be used as the sole basis for excluding a rectal primary. CDX2 is a sensitive marker for rectal origin of adenocarcinoma. It can be helpful in cases with metastatic rectal carcinoma, especially those with CK7+/CK20+ or CK20-/CK7- immunophenotype. In this study, CDX2 expression was not influenced by the grade (differentiation) of rectal adenocarcinoma.

PURPOSE: To investigate the expression of cytokeratin 20 (CK20) and vascular endothelial growth factor (VEGF) in the peripheral blood of colorectal cancer (CRC) patients, and correlate the findings with the pathologic data of the patients. METHODS: This study was carried out on 50 subjects, 40 patients with histologically confirmed colorectal carcinoma undergoing elective surgery and 10 healthy individuals matched for age and sex. Total RNA extraction followed by real time quantitative RT-PCR and real time TaqMan quantitative assay for peripheral blood expression of CK20 and VEGF was done for both patients and controls. RESULTS: (1) Statistically significant high levels of CK20,VEGF, CEA (p = 0.000 each) and CA19-9 (p = 0.002) in CRC patients when compared with controls; (2) Statistically significant increase in the expression of CK20 in advancing CRC stage C (p = 0.001) and with LN metastasis (p = 0.000); (3) Statistically significant increase in the expression of VEGF in advancing CRC stage C (p = 0.002), pathologic grade (p = 0.038), and with LN metastasis (p = 0.004); and (4) statistically positive correlation between CK20 and VEGF expressions, and also between these markers and CEA level. CONCLUSION: CK20 and VEGF expressions in peripheral blood of CRC patients are promising molecular markers for CRC progression and metastasis.

PURPOSE: To investigate the prognostic value of occult metastases detected by quantitative measurements of candidate biomarkers in sentinel lymph nodes (SLNs) from patients curatively resected for colon cancer. METHODS: Resection specimens from consecutive patients undergoing surgery for localized colon cancer were subjected to ex vivo SLN mapping. SLNs were examined for the presence of metastases by routine hematoxylin-erythrosin-safranin staining and by cytokeratin 20 (CK20) and mucin 2 (MUC2) mRNA quantification. The patients were stratified according to KRAS and BRAF mutation status and microsatellite instability status in their primary tumors. Survival end points were analyzed by Kaplan-Meier survival estimates and log-rank tests. RESULTS: A total of 817 SLNs were identified in 206 (97 %) of the 213 included patients. Routine histological examination of SLNs and other regional lymph nodes identified 63 patients with positive nodes (pN+), of which 42 (67 %) were positive in one or more SLNs (sensitivity 67 %, false-negative rate 33 %). On the basis of the CK20 and MUC2 mRNA levels in SLNs, occult metastases were suggested in 86 (60 %) and 52 (36 %) of the 143 otherwise LN-negative (pN0) patients, respectively. Survival analysis with a median 3.6-year follow-up revealed that MUC2 mRNA quantification had significant prognostic value in SLNs from all patients; however, occult SLN metastasis detection did not. CONCLUSIONS: Occult SLN metastases detected by CK20 and MUC2 mRNA quantification had limited prognostic value.

Dynamin 2 is known as a protein involved in cell migration and endocytosis. We aimed to investigate the association between dynamin 2 expressions and tumor progression in early cervical carcinoma (IB1-IIA). Dynamin 2 expression was evaluated at protein level in thirty seven paraffin-embedded, formalin-fixed tissues including four normal cervix tissues and compared with pathologic risk factors for recurrence after surgery in thirty three patients with squamous cell carcinoma of the cervix. The expression of dynamin 2 was not different according to clinical stage and lympho-vascular space invasion. However, there were inverse correlations between dynamin 2 expression and the depth of invasion in cervix (p = 0.003) and lymph node (LN) metastasis (p = 0.001). To evaluate the mechanism of dynamin 2 in tumor invasion and metastasis, we performed an in vitro experiment with dynamin 2 siRNA using several cervical carcinoma cell lines such as HeLa, MS751 and SiHa cells. We found the inhibition of dynamin 2 using specific siRNA enhanced the expression of matrix metalloproteinase-2. These results suggested that dynamin 2 might be involved in preventing tumor invasion and LN metastasis, possibly in relation with extracellular matrix degradation, and may be a prognostic marker for these risk factors in early squamous cell carcinoma of the cervix.

AIM: To evaluate the relationship between vascular invasion and microvessel density (MVD) of tissue and micrometastasis in blood. METHODS: Vascular invasion was detected by both hematoxylin and eosin staining and immunohistochemiscal staining. Blood samples were collected from 17 patients with vascular invasion and 29 patients without vascular invasion and examined for cytokeratin20 (CK20) expression by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Microvessel density of tissue samples was also determined by immunohistochemistry using antibodies to CD105. RESULTS: CK20 was detected in 12 of the 17 patients with vascular invasion and in 9 of the 29 patients without vascular invasion. Positive RT-PCR was significantly correlated with vascular invasion (70.6% vs 30.0%, P < 0.05). The average MVD was significantly higher in patients with positive vascular invasion than in patients with negative vascular invasion (29.2 +/- 3.3 vs 25.4 +/- 4.7, P < 0.05). The vascular invasion detected with hematoxylin-eosin staining was less than that with immunohistochemical staining. There was a significant difference between the two staining methods (19.6% vs 36.9%, P < 0.05). CONCLUSION: Positive CK20 RT-PCR, depth of tumor invasion, lymph node status, metastasis and MVD are significantly correlated with vascular invasion. Immunohistochemical staining is more sensitive than hematoxylin-eosin staining for detecting vascular invasion.