Expression of cytokeratin-20 in endometrial carcinoma

The extent of expression of thyroid transcription factor 1, cytokeratin 7, and anaplastic lymphoma kinase in lung adenocarcinoma

Background:

New forms of genetic alteration were developed giving a new era of lung adenocarcinoma (AdC) with diverse clinical and pathological features.

Aim and Objectives:

The aim is to investigate the ALK-rearranged gene as one of these genetic alterations in AdC. The role of TTF-1 and CK7 is to exclude the metastases.

Material and Methods:

Paraffin-embedded 50 AdC specimens were cut into 4-mm thick sections and stained with the primary antibody, using an anti-TTF-1 antibody, (all at a 1:200 dilution, mouse monoclonal antibody; Dako, Denmark), anti-CK 7 antibody (DAKO, Carpentaria, CA), and the rabbit monoclonal anti- ALK antibody (D5F3) (Ventana, USA). Positive reactivity was considered as brown nuclear immunostaining for TTF-1 and cytoplasmic for CK 7and both cytoplasmic and nuclear for ALK.

Results:

The median age was 56±2, with male to female ratio 7:3. Forty-four cases revealed a mixed pattern (88%), with focal intraluminal mucin. Forty-one cases (82%) were positive for TTF-1, of these; weak (13; %), moderate (16; %) and strong (12; %). Regarding CK7; 48 cases (96%) were positive; weak (7 cases; 14.5; %), moderate (18 cases; 37.5%) and strong (23 case; 47.9 %) of the positive cases. Regarding D5F3; five cases (10%) were positive; weak (1 case; 20 %), moderate (2 cases; 40 %) and strong (2 cases; 40%) out of the positive cases. Four ALK-positive cases were male and ALK-positive patients ranged from 42-55 years with median 48.

Conclusion:

Despite the incidence of ALk-AdC is uncommon, it might be suspected in lesions of lower age group especially with mucinous foci.

Metastasis to left scapula with unknown primary: Approach to pathological diagnosis

Bony metastasis is a frequent occurrence in malignancy. However, the clinical presentation and pathological findings may sometimes be more in favor of a primary bone lesion. In such cases, immunochemistry has a very important role to play in reaching a final diagnosis. We present the case of a 35 year male patient who was investigated for a lytic lesion in the left scapula and was finally diagnosed with metastatic adenocarcinoma with the help of immunostaining.

Real-time quantitative RT-PCR detection of disseminated endometrial tumor cells in peripheral blood and lymph nodes using the LightCycler System

OBJECTIVE

Some endometrial cancer patients without clinical evidence of extrauterine spread die as a result of recurrence even after curative operation. These recurrences may arise from occult tumor cells that are not detected by conventional methods. The goal of this study was to develop a quantitative method for the detection of disseminated tumor cells (DTCs) in the peripheral blood (PB) and lymph nodes (LNs) of patients with endometrial cancer.

METHODS

Ninety-eight PB samples from 30 patients and 218 LNs from 14 patients were studied. Real-time quantitative analysis was performed using a LightCycler instrument and a TaqMan probe for cytokeratin 19 (CK19) as a marker gene.

RESULTS

This method resulted in the reproducible quantitation of 10 to 10(6) MCF-7 cells (CK19-expressing breast cancer cell line) per 10(6) peripheral blood nucleated cells. CK19 mRNA expression was detected in 28 PB samples and in 62 LNs. Only three preoperative PB samples and one postoperative PB sample (from four patients) and 33 LNs (from six patients) were PCR-positive. The PCR-positive rate of LNs was higher in patients with pathologically metastatic (path-positive) LNs than in patients with path-negative but PCR-positive LNs. Furthermore, the CK19 mRNA background expression rate was higher in the LNs of path-negative but PCR-positive patients than in LNs of path-negative and PCR-negative patients.

CONCLUSIONS

Real-time qRT-PCR with TaqMan probes is a sensitive, specific and rapid method for the detection of DTCs in PB and LNs. Additional studies with larger numbers of patients and adequate follow-up would be of benefit.

Progestin suppresses matrix metalloproteinase production in endometrial cancer

OBJECTIVES

Endometrial carcinoma (EC) is one of the few cancers where there is a clear relationship between excessive hormone stimulation and malignant transformation. In this study we have analyzed the effects of the female sex steroids estrogen and progesterone on matrix metalloproteinases (MMP-9 and -2) production in primary EC cells and EC cell lines. MMPs are implicated in cancer invasion via mechanisms including extracellular matrix degradation and the processing of a range of molecules, including growth factors and cytokines.

METHODS

Cells were isolated from biopsies collected from three cancer patients undergoing hysterectomy for grade 1 endometrial adenocarcinoma and two patients undergoing procedures unrelated to EC. These cells plus the EC cell lines Ishikawa and HEC-1A were cultured without hormones or with medroxyprogesterone acetate (MPA), estradiol (E(2)), or these hormones in combination. Gelatin and reverse zymography were used to analyze MMPs and TIMPs, respectively, in culture medium. RT-PCR was used to characterize steroid receptor expression.

RESULTS

Cell lines differed from primary cells in the range and abundance of MMPs secreted. Treatment with MPA significantly reduced proMMP-9, proMMP-2, and MMP-2 release from primary EC cancer and stromal cells. Treatment with E(2) alone or MPA + E(2) had no significant effect on MMP expression. Primary EC and stromal cells also showed a loss of the progesterone B receptor isoform.

CONCLUSION

EC cells retain the suppression of MMPs by progesterone, seen in normal endometrial cells. These data provide a rationale for the use of progestin therapy in the treatment of early stage grade 1 endometrial carcinomas.

Cytokeratin 20 as a biomarker of gestational trophoblastic disease: diagnostic and prognostic significance

OBJECTIVES

This study was designed to examine whether cytokeratin 20 (CK20) is expressed in molar pregnancies and may therefore be used in the diagnosis of gestational trophoblastic disease (GTD). The potential of CK20 expression in predicting the evolution and the prognosis of the different subtypes of GTD was also assessed.

METHODS

A total of 48 samples were studied for CK20 expression by RT-PCR methodology. Among these, 24 samples were obtained by curettage of the uterine cavity of patients diagnosed with hydatidiform mole (14 complete moles and 10 partial moles), 4 samples were obtained from choriocarcinoma cell lines (2 JAR and 2 JEG), and 20 samples were of normal trophoblast (control group) obtained from patients that underwent elective termination of pregnancy.

RESULTS

Expression of CK20 was identified in all the samples of complete mole (CM), all choriocarcinoma cell lines, and 50% of the patients with partial mole (PM). None of the preparations of normal trophoblastic tissue from the control group expressed the CK20. A significant difference (P < 0.00001) was found in CK20 expression between samples of patients with GTD and control samples. Comparison between CK20 expression in CMs and PMs revealed a significantly more frequent expression of CK20 in CMs (P = 0.006). More than 50% of the patients with PMs that were positive for CK20 had an invasive evolution.

CONCLUSIONS

In our opinion, CK20 may assist in distinguishing between molar and normal trophoblastic tissue and may be considered a marker of GTD. In cases in which pathological classification of different subtypes of GTD is in doubt, CK20-positive expression is suggestive for a CM whereas CK20-negative is more indicative for PM.

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.

Expression of cytokeratins 7 and 20 in ovarian neoplasia

To further delineate specific staining patterns and refine the differential usefulness of cytokeratin (CK) 7/20 staining, we studied multiple ovarian tumors and primary nongynecologic neoplasms likely to metastasize to the ovary. Immunohistochemical analysis with semiquantitative grading to give quartile scores (0-4) was performed on 127 cases. Subsequent analysis indicated that a more informative diagnostic segregation could be achieved with a biphasic grading system (>50% staining, positive; 50% or less, negative). Lower intestinal tumors were CK7- and usually CK20+, while upper gastrointestinal tumors, including those of pancreatobiliary origin, were mostly CK7+ and CK20-. Serous papillary ovarian tumors were all CK7+ and CK20-. Mucinous ovarian carcinomas were all CK7+ and slightly more often CK20-, whereas the small number of ovarian borderline mucinous tumors studied were the most problematic, with no clear pattern. Multiple different tumor types from all nonovarian gynecologic sites were fairly consistently CK7+ and almost always CK20-. Differential CK staining of mucinous tumors of the female genital tract using CK7 and CK20 is useful for predicting the site of origin, provided samples are adequate in size. The most specific usefulness is the identification of lower gastrointestinal vs "other" neoplasms.

Genetic alterations in endometrial hyperplasia and cancer

Putative precursors of endometrial cancer such as complex endometrial hyperplasia with atypia have been described to be monoclonal and considered to be genetically related. In order to identify a genetic marker that could serve as a putative predictor of endometrial cancer we analyzed 14 endometrial hyperplasia and 29 endometrial cancer samples for instabilities and loss of heterozygosity (LOH) in microsatellite sequences. Deletions on the short arm of chromosome 8 were frequently detected in both endometrial hyperplasia and cancer samples, suggesting that these deletions are early events in the development of endometrial cancer.

Detection of tumor circulating cells by cytokeratin 20 in the blood of patients with endometrial carcinoma

BACKGROUND

Cytokeratins 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 technique (RT-PCR) we recently demonstrated that: (1) Cytokertin 20-the most recent discovered cytokeratin-is expressed in endometrial carcinoma tumors but not in the endometrium of patients with benign diseases, and (2) CK-20 is not expressed in blood cells. The aim of this study is 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 endometrial carcinoma.

METHODS

In the present study, we have used RT-PCR to determine the expression of CK-20 in the peripheral blood of the following groups: (1) preop new diagnosed patients (n = 20), (2) patients with no clinical evidence of disease following completion of definitive treatment (n = 33; 17 at low risk; 16 at high risk), (3) patients with recurrent disease (n = 6), and (4) a control group of healthy subjects (n = 16). RNA was extracted from cell pellets and analysed by RT-PCR using primers for CK-20.

RESULTS

Of the 20 patients of the first group 7 (35%) were CK-20 positive. Of the 33 patients of the second group 17 (51%) were CK-20 positive. Subdivision of this group showed that 9 of 17 (53%) were positive in the low-risk subgroup, and 8 of 16 (50%) were positive in the high-risk subgroup. All 6 patients with recurrent disease were positive, and all subjects in the control group were negative.

CONCLUSION

These results indicate that RT-PCR of CK-20, because of its high sensitivity, is a potential biomarker for detecting metastasis in blood samples of patients with endometrial carcinoma.

Cytokeratin 7 and cytokeratin 20 expression in epithelial neoplasms: a survey of 435 cases

Cytokeratin 7 (CK 7) and cytokeratin 20 (CK 20) are low molecular weight cytokeratins. Their anatomic distribution is generally restricted to epithelia and their neoplasms. We surveyed 435 epithelial neoplasms from various organ systems by immunohistochemistry using CK 7 and CK 20 monoclonal antibodies. Expression of CK 7 was seen in the majority of cases of carcinoma, with the exception of those carcinomas arising from the colon, prostate, kidney, and thymus; carcinoid tumors of the lung and gastrointestinal tract origin; and Merkel cell tumor of the skin. The majority of cases of squamous cell carcinoma of various origins were negative for CK 7, except cervical squamous cell carcinoma, in which 87% of cases were positive. Approximately two thirds of cases of malignant mesothelioma were CK 7-positive. CK 20 positivity was seen in virtually all cases of colorectal carcinomas and Merkel cell tumors. CK 20-positive staining was also observed in cases of pancreatic carcinomas (62%), gastric carcinoma (50%), cholangiocarcinomas (43%), and transitional cell carcinomas (29%). The expression of CK 20 was virtually absent in carcinomas from other organ systems and in malignant mesothelioma. CK 7- and CK 20-negative epithelial neoplasms included adrenal cortical carcinoma, germ cell tumor, prostate carcinoma, renal cell carcinoma, and hepatocellular carcinoma.

Detection of micrometastasis by cytokeratin-20 (reverse transcription polymerase chain reaction) in lymph nodes of patients with endometrial cancer

BACKGROUND

Cytokeratins are constituents of the intermediate filaments (IFs) of epithelial cells which are expressed in various combinations, depending on the type of epithelium and degree of differentiation. We have reported (R. Zemer, A. Fishman, J. Bernheim, S. Zimlichman, O. Markowitz, M. Altaras, and A. Klein, Gynecol Oncol 70:410-413, 1998) on the determination of cytokeratin-20 (CK-20) by reverse transcription polymerase chain reaction (RT-PCR) in the detection of endometrial cancer cells as a potential biomarker. In that study, we also found that by using immunocytochemistry, most carcinomas were found to be negative for CK-20. The sensitivity and specificity rates obtained by using the RT-PCR method were 94.4 and 91%, respectively.

OBJECTIVE

The aim of this study is to investigate the feasibility and potential of the specific mRNA marker, CK-20, to detect endometrial cancer cells-micrometastases (MMs)-by RT-PCR in lymph node (LN) samplings of patients undergoing hysterectomy for endometrial carcinoma.

METHOD

We used the RT-PCR method to determine the expression of CK-20 in the LNs of 20 patients [study group (SG)] who were being surgically staged and treated for endometrial carcinoma. The specificity of the mRNA CK-20 marker was examined in LNs obtained from five healthy patients [control group (CG)] who underwent abdominal hysterectomy and bilateral salpingo-oopherectomy for benign gynecologic conditions. The LNs obtained from the SG and CG patients were prepared together before mRNA extraction. RNA of the various cell pellets was extracted and RT-PCR was performed with CK-20 primers. RT-PCR products were analyzed by agarose gel electrophoresis and ethidium bromide staining against PCR size markers. Specificity of the RT-PCR products was examined by Southern blotting.

RESULTS

Histopathologic examinations demonstrated the presence of metastases in two (10%) SG patients. These patients were also CK-20 positive. Of the remaining 18 patients with negative histopathologic results, 6 (33%) were CK-20 positive and 12 (67%) were negative. All the CG patients were CK-20 negative (specificity, 100%).

CONCLUSIONS

The results obtained in this study suggest that RT-PCR of CK-20 is more sensitive than traditional histopathologic methods in the diagnosis of MMs in LNs of patients with endometrial cancer. Thus, due to the aforementioned characteristics of CK-20, it may be considered a powerful biomarker in the detection of MMs in LNs of patients with endometrial cancer.

The zinc finger repressor, ZBP-89, binds to the silencer element of the human vimentin gene and complexes with the transcriptional activator, Sp1

Vimentin is a component of the eukaryotic cytoskeleton belonging to the family of intermediate filament proteins. It exhibits a complex pattern of tissue- and development-specific expression. It is also a marker of the metastatic potential of many tumor cells. Previously, the human vimentin promoter was shown to contain several regions for the binding of positive and negative acting regulatory factors. Until now, the silencer element, which shuts down vimentin synthesis in selected tissues during development, was not precisely localized; nor was its binding protein known. In vivo DMS footprinting by ligation-mediated PCR delineated the position of guanine residues important to vimentin expression. Transient transfection assays in HeLa cells of various vimentin 5'-end promoter sequences and mutants thereof precisely defined two regulatory elements, a negative element and an adjoining positive acting element. Band shift assays, UV cross-linking, and Southwestern blot analysis confirm that the silencer element specifically binds a protein. Several lines of evidence show that ZBP-89, a zinc finger, Kruppel-like repressor protein is vimentin's silencer element binding factor. Co-immunoprecipitation and DNA affinity chromatography prove that Sp1 heterodimerizes with ZBP-89 when bound to the silencer element to yield a DNA-protein complex whose mobility is indistinguishable from that displayed by HeLa nuclear extract in band shift assays.