Complexity of expression of intermediate filament proteins, including glial filament protein, in endometrial and ovarian adenocarcinomas

An Assessment of the Mechanophysical and Hormonal Impact on Human Endometrial Epithelium Mechanics and Receptivity

The endometrial epithelium and underlying stroma undergo profound changes to support and limit embryo adhesion and invasion, which occur in the secretory phase of the menstrual cycle during the window of implantation. This coincides with a peak in progesterone and estradiol production. We hypothesized that the interplay between hormone-induced changes in the mechanical properties of the endometrial epithelium and stroma supports this process. To study it, we used hormone-responsive endometrial adenocarcinoma-derived Ishikawa cells growing on substrates of different stiffness. We showed that Ishikawa monolayers on soft substrates are more tightly clustered and uniform than on stiff substrates. Probing for mechanical alterations, we found accelerated stress-relaxation after apical nanoindentation in hormone-stimulated monolayers on stiff substrates. Traction force microscopy furthermore revealed an increased number of foci with high traction in the presence of estradiol and progesterone on soft substrates. The detection of single cells and small cell clusters positive for the intermediate filament protein vimentin and the progesterone receptor further underscored monolayer heterogeneity. Finally, adhesion assays with trophoblast-derived AC-1M-88 spheroids were used to examine the effects of substrate stiffness and steroid hormones on endometrial receptivity. We conclude that the extracellular matrix and hormones act together to determine mechanical properties and, ultimately, embryo implantation.

Effect of Baicalin on Wound Healing in a Mouse Model of Pressure Ulcers

One of the most frequent comorbidities that develop in chronically ill or immobilized patients is pressure ulcers, also known as bed sores. Despite ischemia-reperfusion (I/R)-induced skin lesion having been identified as a primary cause of pressure ulcers, wound management efforts have so far failed to significantly improve outcomes. Baicalin, or 5,6,7-trihydroxyflavone, is a type of flavonoid which has been shown to possess a variety of biological characteristics, including antioxidative and anti-inflammatory effects and protection of I/R injury. In vitro wound scratch assay was first used to assess the function of baicalin in wound healing. We established a mouse model of advanced stage pressure ulcers with repeated cycles of I/R pressure load. In this model, topically applied baicalin (100 mg/mL) induced a significant increase in the wound healing process measured by wound area. Histological examination of the pressure ulcer mouse model showed faster granulation tissue formation and re-epithelization in the baicalin-treated group. Next, baicalin downregulated pro-inflammatory cytokines (IL-6 and IL-1β), while upregulating the anti-inflammatory IL-10. Additionally, baicalin induced an increase in several growth factors (VEGF, FGF-2, PDGF-β, and CTGF), promoting the wound healing process. Our results suggest that baicalin could serve as a promising agent for the treatment of pressures ulcers.

Cytokeratins in the Histological Diagnosis of Malignant Tumors

Cytokeratins, which comprise a multigene family of 20 related polypeptides (CKs 1–20), are constituents of the intermediate filaments of epithelial cells, in which they are expressed in various combinations depending on the epithelial type and the degree of differentiation. Of these, CK 19 (400 amino acids; 44.1 kilodaltons) is an example of a widely distributed CK, being expressed in various epithelia, including many simple epithelia. In contrast, the recently identified CK 20 (424 amino acids; 48.6 kilodaltons) is essentially confined to gastrointestinal epithelia, the urothelium and Merkel cells. The differential expression of individual CKs in various types of carcinomas makes them useful markers for histopathological carcinoma subtyping, providing relevant information concerning the differentiation and origin of carcinomas, especially when tumors first present as metastases. The CKs that are of particular value for differential diagnosis include CK 20, as it is mainly expressed in carcinomas derived from CK 20-positive epithelia; it is also found in bile-tract, pancreatic and mucinous ovarian adenocarcinomas, being absent in most other carcinomas. In certain carcinoma types, the changes in the expression of individual CKs that may occur during tumor progression could be of prognostic relevance. It remains to be established whether the serological detection of fragments of not only widely distributed but also more restrictedly expressed CKs may provide useful serological tumor markers in the future.

Primitive Neuroectodermal Tumors of the Female Genital Tract: A Morphologic, Immunohistochemical, and Molecular Study of 19 Cases

Primary primitive neuroectodermal tumor (PNET) of the female genital tract is rare, and its proper classification remains unclear. The clinical, histologic, and immunophenotypic features as well as EWSR1 rearrangement status of 19 gynecologic PNETs, including 10 ovarian, 8 uterine, and 1 vulvar tumors, are herein reported. Patient age ranged from 12 to 68 years, with a median age of 20 and 51 years among those with ovarian and uterine PNETs, respectively. Morphologic features of central nervous system (CNS) tumors were seen in 15 PNETs, including 9 medulloblastomas, 3 ependymomas, 2 medulloepitheliomas, and 1 glioblastoma, consistent with central PNET. The remaining 4 PNETs were composed entirely of undifferentiated small round blue cells and were classified as Ewing sarcoma/peripheral PNET. Eight PNETs were associated with another tumor type, including 5 ovarian mature cystic teratomas, 2 endometrial low-grade endometrioid carcinomas, and a uterine carcinosarcoma. By immunohistochemistry, 17 PNETs expressed at least 1 marker of neuronal differentiation, including synaptophysin, NSE, CD56, S100, and chromogranin in 10, 8, 14, 8, and 1 tumors, respectively. GFAP was positive in 4 PNETs, all of which were of central type. Membranous CD99 and nuclear Fli-1 staining was seen in 10 and 16 tumors, respectively, and concurrent expression of both markers was seen in both central and Ewing sarcoma/peripheral PNETs. All tumors expressed vimentin, whereas keratin cocktail (CAM5.2, AE1/AE3) staining was only focally present in 4 PNETs. Fluorescence in situ hybridization was successful in all cases and confirmed EWSR1 rearrangement in 2 of 4 tumors demonstrating morphologic features of Ewing sarcoma/peripheral PNET and concurrent CD99 and Fli-1 expression. In conclusion, central and Ewing sarcoma/peripheral PNETs may be encountered in the female genital tract with central PNETs being more common. Central PNETs show a spectrum of morphologic features that overlaps with CNS tumors but lack EWSR1 rearrangements. GFAP expression supports a morphologic impression of central PNET and is absent in Ewing sarcoma/peripheral PNET. Ewing sarcoma/peripheral PNETs lack morphologic features of CNS tumors.

Papillary ependymoma of the endometrium

AIMS

To report an exceptional case of papillary ependymoma occurring in the endometrium.

METHODS AND RESULTS

A clinicopathological study was performed regarding a case of papillary ependymoma occurring in the endometrial cavity of a 61-year-old patient who had presented with a solid-type, stage III anaplastic ependymoma of the ovary, treated with cytoreductive surgery that included total abdominal hysterectomy. The uterus was enlarged and showed a dilated cavity, with broadly implanted papillary excrescences without myometrial invasion that were covered by tall, cylindrical cells. These cells had glial fibrillary acidic protein-expressing cytoplasm that was also positive for cytokeratins 7, 8, 18, and 34β-E12, epithelial membrane antigen, S100 protein, vimentin, and oestrogen and progesterone receptors.

CONCLUSIONS

Pathogenetically, the presence of this uterine ependymoma could represent either an example of multicentricity or a phenomenon of transtubal implantation of the ovarian tumour. Exceptionally, papillary ependymoma can occur in the endometrium, and may prompt differential diagnoses with other papillary endometrial tumours. Pathologists should consider this rare possibility in the differential diagnosis of papillary ovarian and endometrial lesions.

Determining the site of origin of mucinous adenocarcinoma: an immunohistochemical study of 175 cases

Mucinous adenocarcinomas (MAs) of various origins may have a similar histologic appearance and frequently metastasize to distant sites, which often causes diagnostic problems in surgical pathology practice. The immunohistochemical profiles of MAs of various origins have not been well studied. We investigated the expression of 10 immunohistochemical markers (CK7, CK20, CDX-2, β-catenin, MUC-1, MUC-2, MUC-6, ER, WT-1, and PAX-8) in 175 cases of MA, including 69 cases from the lower gastrointestinal (GI) tract, 41 from the upper GI tract, 27 from gynecologic organs, 4 from the urinary bladder, 18 from the breast, and 16 from the lung. We found that lower GI MAs (colon, rectum, and anus) frequently expressed CDX-2 (42 of 42, 100%; 33 of 42 with homogenous positivity, 79%), MUC-2 (42 of 42; 100%), CK20 (41 of 42; 98%), and β-catenin (nuclear) (27 of 42; 64%) and rarely expressed MUC-6 (2 of 42; 5%) and CK7 (8 of 42; 19%). Most of the CK7-positive cases were from the rectum and anus (7 of 8; 88%). The expression of these markers in appendiceal MAs was similar to that of low GI tract MAs, except for a lower percentage of homogenous CDX-2 (3 of 27; 11%) and nuclear β-catenin (3 of 27; 11%) expression. Unlike their lower GI tract counterparts, the upper GI tract MAs (ampulla, pancreas/biliary tree, and stomach/esophagus) frequently expressed CK7 (38 of 41; 93%) and MUC-6 (31 of 41; 76%) and were rarely homogenously positive for CDX-2 (4 of 41; 10%) and nuclear positive for β-catenin (8 of 41; 19%). Breast MAs were frequently positive for CK7 (18 of 18; 100%), MUC-1 (18 of 18; 100%), MUC-2 (18 of 18; 100%), ER (16 of 18; 89%), MUC-6 (9 of 18; 50%), and WT-1 (9 of 18; 50%). Lung MAs were frequently positive for CK7 (16 of 16; 100%) and MUC-1 (15 of 16; 94%). Gynecologic MAs were positive for CK7 (25 of 27; 93%) and PAX-8 (13 of 27; 48%). We conclude that homogenous CDX-2 and nuclear β-catenin expressions are commonly seen in lower GI tract MAs. In contrast, appendiceal MAs are usually heterogenously positive for CDX-2 and show cytoplasmic positivity for β-catenin. Unlike lower GI tract MAs, upper GI tract MAs are frequently positive for CK7 and MUC-6. As is the case in appendiceal MAs, the upper GI tract MAs may also be heterogenously positive for CDX-2. Breast MAs are positive for ER and WT-1, whereas gynecologic MAs are positive for PAX-8 and negative for WT-1.

Clinicopathologic and immunohistochemical profile of ovarian metastases from colorectal carcinoma

Metastasis of colorectal adenocarcinoma of the ovary is not an uncommon occurrence and ovarian metastases from colorectal carcinoma frequently mimic endometrioid and mucinous primary ovarian carcinoma. The clinical and pathologic features of metastatic colorectal adenocarcinoma involving the ovary is reviewed with particular focus on the diagnostic challenge of distinguishing these secondary ovarian tumors from primary ovarian neoplasm. Immunohistochemical stains that may be useful in the differential diagnosis of metastatic colorectal tumors to the ovary and primary ovarian tumors are detailed.

Ultrastructure of ectopic peritoneal lesions from women with endometriosis, including observations on the contribution of coelomic mesothelium

Following a study in a baboon model of endometriosis, we here describe the morphology of ectopic peritoneal lesions in the human to examine the effects of an ectopic site on glandular structure and function. Ectopic biopsies from 17 women with endometriosis were fixed and processed for electron microscopy. Certain biopsies were also probed for intermediate filaments using immunohistochemistry. Ultrastructurally, lesions showed many different glandular morphologies with indications of delayed maturation compared to normal endometrium. Mesothelium covered some lesions and there was evidence of mesothelial invasion into the stroma. Ectopic endometriotic lesions from women with endometriosis showed ultrastructural differences from eutopic endometrium, with indications that mesothelial invasion may contribute to gland development in some lesions.

Immunohistochemical biomarkers of value in distinguishing primary ovarian carcinoma from gastric carcinoma: a systematic review with statistical meta-analysis

AIMS

To compare the relative risk of antigen expression being detected immunohistochemically in ovarian and gastric carcinoma aggregated from studies performed for diagnostic purposes, with the relative risks of their expression in all patients in the English literature.

METHODS AND RESULTS

Both types of series indicated that cytokeratin (CK) 7 expression was greater and that of CK20 and carcinoembryonic antigen less in ovarian than in gastric carcinoma (P < 0.05). Synthesis of all data available for MUC-2 suggested it was more commonly expressed in ovarian carcinoma, whereas the relative risk in papers that directly compared its expression suggested that it was more common in the gastric carcinoma (P = 0.2, NS). Aggregating all possible data suggested villin was more likely to be expressed in ovarian cancers, whereas studies in which its expression was compared directly in both tumours suggested the opposite. Although statistically significant, patient numbers were small.

CONCLUSION

Provided sufficient numbers of cases are studied, analysis of studies comparing antigen expression for diagnostic purposes in tumours from two body sites is likely to be supported in the wider literature. The design of such comparative studies is informed by aggregating data from single tumour studies.

Utility of CDX-2 in distinguishing between primary and secondary (intestinal) mucinous ovarian carcinoma: an immunohistochemical comparison of 43 cases

Primary and secondary mucinous tumors can involve the ovaries and have similar histologic appearances. The differential diagnosis is important for surgical and chemotherapeutic treatment and for the prognosis, but often it is extremely difficult. This article discusses an immunohistochemical panel that includes carcinoembryonic antigen (CEA), cytokeratin (CK) 7, CK20, CA125, CA19.9, and a new marker, CDX-2, for the distinction between primary ovarian mucinous carcinomas and metastatic (intestinal) ovarian tumors. Forty-three cases representing primary and secondary ovarian tumors were considered and consisted of 14 primary mucinous ovarian carcinomas (PMOCs) and 29 secondary (intestinal) ovarian tumors (SIOTs). Fisher exact test was performed to evaluate the reliability of the respective antibodies to discriminate between PMOCs and SIOTs. CDX-2 was diffusely positive in all SIOTs and was expressed focally in 3 cases (21.42%) of PMOCs. CK7 was diffusely positive in 13 cases (44.82%) of SIOTs and in 13 cases (92.85%) of PMOCs. CK20 was diffusely positive in 17 cases (58.62%) of SIOTs and in 6 cases (42.85%) of PMOCs. CEA was diffusely positive in 28 cases (96.55%) of SlOTs and in 12 cases (85.71%) of PMOCs. CA 19.9 was positive in all SIOTs and in 12 cases (85.71%) of PMOCs. CA125 was positive in 3 cases (10.34%) of SIOTs and in 4 cases (28.57%) of PMOCs. CK7 and especially CDX-2, a specific and sensitive marker, can aid pathologists in making a differential diagnosis (P = 0.003 and P < 0.0005, respectively), whereas CEA, CK20, CA125, and CA 19.9 markers are not high enough to distinguish between primary and secondary mucinous ovarian tumors.

Ovarian Papillary Cystadenocarcinomas in a Green Iguana (Iguana iguana)

The clinical, gross morphological and histological characteristics of bilateral ovarian papillary cystadenocarcinomas in an adult female green iguana (Iguana iguana) are documented in this report. Histologically, the tumour consisted of an invasive mass of small glandular structures, irregular arboriform papillae and cystic structures arising from the ovarian surface epithelium. Metastatic implants were extensively disseminated along the serosa of the coelomic viscera, mesentery and fat bodies. Tumour morphology and metastatic behaviour indicated a close resemblance to cystadenocarcinoma in other species. Primary ovarian neoplasia is rare in reptiles; documented cases include tumours arising from surface epithelium, germ cells and sex cord stroma.

Intermediate-filament expression in ocular tissue

Intermediate-filament proteins (IFPs) occur in the intracellular cytoskeleton of eukaryotic cells, and their expression in diverse tissues is related both to embryology as well as to differentiation. Although the available information concerning their functional properties in vivo is still incomplete, antibodies against individual IFPs are commonly used in immunohistochemical procedures as markers for differentiation, and these antibodies are of outstanding value in the routine histopathological evaluation of tumor specimens. This review presents a compilation of the currently available data concerning IFP expression in normal and diseased ocular tissues. Representatives of every known class of IFP have been detected in normal ocular tissues. The external epithelia exhibit complex expression patterns of cytokeratin (CK) polypeptides, with CK3 and CK12 being specific markers of the corneal epithelium. Recent research has revealed that single mutant CK polypeptides may play a role in the pathogenesis of corneal dystrophies. The internal ocular epithelia reveal simple but specific patterns of IFP expression, these comprising simple-epithelial CKs and/or the mesenchymal IFP, vimentin. The IFP complement of the neuronal structures of the eye embraces several distinct IFP classes and reflects the diversity of the cell types present at these sites. With respect to ocular tumors, the IFP profile of melanomas might be correlated with metastatic potential. In conclusion, IFP analysis may be able to cast light on the pathogenesis of ocular diseases, as well as being a valuable adjunct in ophthalmopathological diagnosis.

Characterization of a human carcinosarcoma cell line of the ovary established after in vivo change of histologic differentiation

OBJECTIVES

Cell lines are valuable in vitro models for clinical and basic research. Most ovarian cancer cell lines described are serous cystadenocarcinomas or poorly differentiated adenocarcinomas. The establishment of ovarian cancer cell lines with rare histologic differentiation is especially of interest. We describe the establishment of a carcinosarcoma cell line of the ovary after in vivo selection.

METHODS

The cell line OV-MZ-22 was established from a solid tumor mass in the upper abdomen. At the time of establishment, the patient underwent secondary debulking and was pretreated with six cycles of cis-platinum/epirubicin/cyclophosphamide. Features of the cell line studied included morphology, ultrastructure, heterotransplantation, chromosome analysis, and analysis of intermediate filament proteins and actins by immunocytochemistry.

RESULTS

The first histologic report of the patient described a papillary cystadenocarcinoma, which changed to a carcinosarcoma with predominantly sarcomatous differentiation at secondary debulking. This cell line is aneuploid and shows no expression of the tumor-associated antigens CA-125 and CEA, but an overexpression of MDR-1, lung resistance protein, p53, and topoisomerase I and II, but not of multidrug-resistance-associated protein. The cell line did not give rise to transplant tumors in nude mice. The histologic and immunocytochemical comparison of the primary and the relapsed tumor proved evidence of an in vivo change of differentiation from predominantly papillary cystadenocarcinoma to carcinosarcoma. Morphological characteristics and intermediate filament pattern underlined the sarcomatous differentiation and origin of this cell line. The differentiation phenotype of OV-MZ-22 cells is that of smooth-muscle cells.

CONCLUSION

The change of histologic differentiation was apparently due to a selection process caused by platinum-containing chemotherapy. The origin of the cell line and its rarity make this new line an appropriate tool for further investigation.

Immunohistochemical differentiation between primary adenocarcinomas of the ovary and ovarian metastases of colonic and breast origin. Comparison between a statistical and an intuitive approach

AIM

To discriminate between adenocarcinomas that are primary to the ovary and metastatic to the ovary, especially of colonic and breast origin, by immunohistochemistry, using stepwise discriminant analysis or a decision tree.

METHODS

312 routinely processed, formalin fixed tissue specimens were used. The tumours were divided into a learning set (n = 159), composed of primary tumours of ovary, breast, and colon, and a test set, comprising 134 metastases from these sites and an additional 19 primary ovarian carcinomas. The immunohistochemical panel was composed of antibodies against cytokeratin 7 (CK7) and 20 (CK20), CA125, vimentin, carcinoembryonic antigen (CEA), gross cystic disease fluid protein-15 (GCDFP-15), and the oestrogen receptor (ER). The staining results of the tumours were expressed as the product of the staining intensity and the percentage of positive tumour cells. Analyses were first performed on the learning set and then evaluated on the test set.

RESULTS

Although the immunostaining patterns showed a considerable overlap between the three types of adenocarcinoma, the breast carcinomas were typically positive for GCDFP-15 and often for ER, and negative for vimentin. Ovarian carcinomas were always positive for CK7 and to a lesser extent for CA125. Colonic carcinomas showed prominent positivity for CEA and CK20, while no staining was seen for ER and vimentin. In discriminant analysis, six antibodies (alpha CK7, alpha CK20, alpha CA125, alpha CEA, alpha ER, and alpha GCDFP-15) appeared to be necessary for optimal classification: 89% of the learning set and 82% of the test set were classified correctly. In the decision tree, only four antibodies (alpha CK7, alpha CEA, alpha ER, and alpha GCDFP-15) were used to obtain a correct classification score of 89% for the learning set and 84% for the test set.

CONCLUSIONS

Using a semiquantitative assessment of the immunostaining results by a restricted panel of six antibodies with stepwise discriminant analysis, 80-90% of the adenocarcinomas of colon, breast, and ovary can be correctly classified. Discriminant analysis is computer aided and therefore an easy method and for each case a probability value of the classification result is obtained. The intuitive decision tree method provides a slightly better result, requires only four antibodies, and offers a more practical method for the surgical pathologist.

Multidirectional differentiation of endometrial carcinoma with special reference to tumor aggressiveness evaluated by Ki-67 expression

To clarify the correlation between multidirectional differentiation and aggressiveness of endometrial adenocarcinomas, we assessed both proliferative activities (PA) using Ki-67 expression and squamous and/or endocrine differentiation. We divided 51 adenocarcinomas into 22 adenocarcinomas with typical squamous differentiation (>/=10% of tumor cells, typical SQ) classified into 10 adenoacanthomas (AA) and 12 adenosquamous carcinomas (AS), 17 adenocarcinomas with focal squamous differentiation (<10% of tumor cells), and 12 typical adenocarcinomas without morphological squamous differentiation (pure AC), according to the new WHO classification. Paraffin-embedded sections were stained using monoclonal antibodies against high-molecular-weight keratins (HMWK) to recognize squamous cells, chromogranin A to recognize endocrine cells, and Ki-67 antigen to recognize proliferating cells. Both AA and AS exhibited lower PA than pure AC. Typical SQ exhibited lower PA than pure AC. This difference was also significant after selecting only grade 1 or stage I/II cases. AA exhibited lower PA than AS and also after selecting only grade 1 or stage I/II cases. PA of adenocarcinoma with the expression of HMWK in >/=30% of tumor cells was lower than those without HMWK. PA of adenocarcinoma with the expression of chromogranin A in >/=10% of tumor cells was lower than those without chromogranin A. These differences were also significant after selecting only grade 1 or stage I/II cases. Squamous and/or endocrine differentiation is a good marker for a reduction of PA. Endometrial adenocarcinomas with multidirectional differentiation exhibited lower PA and were likely to be more mature than those with monodirectional differentiation.

Tracing the origin of adenocarcinomas with unknown primary using immunohistochemistry: differential diagnosis between colonic and ovarian carcinomas as primary sites

To discriminate adenocarcinoma metastases originating from either colon or ovary, a panel of immunohistochemical markers was evaluated. For this purpose, paraffin sections from 157 primary and metastatic colonic and ovarian carcinomas were immunostained. These cases were divided into a learning group of 46 colonic and 54 ovarian carcinomas and a test group of 29 colonic and 28 ovarian carcinomas, including all metastatic tumors, among which were five with unknown primary site at the time of testing. The sections were immunostained with antibodies against carcinoembryonic antigen (CEA), cytokeratin 7 (CK7), cytokeratin 20 (CK20), CA125, vimentin, and CA19.9. Staining results were expressed as the product of staining intensity and percentage of positive tumor cells. Stepwise discriminant analysis was applied on the learning set to obtain a classification function for both tumors. The validity of the classification function was evaluated using the test set. There was considerable overlap in immunostaining for both tumor types, but colonic carcinomas were typically positive for CEA and CK20 and negative for CK7 and CA125. Ovarian carcinomas were typically positive for CK7 and CA125 and negative for CEA and CK20. In discriminant analysis, the best combination of markers appeared to be CK7 and CEA. Only one sample of the test group (2%) was misclassified. Taking learning and test groups together, 136 of the 157 samples (87%) were correctly classified with high posterior probability (PP > .8). However, from the 28 mucinous ovarian carcinomas, only 19 (68%) could correctly be classified with high PP. When excluding the nonmucinous ovarian carcinomas from the analysis, overall 87 of 103 (84.5%) of the samples were correctly classified (PP > .8) with a combination of CEA, CK7, and also vimentin. From the 28 mucinous ovarian carcinomas, only two (7%) were misclassified, and four could not be classified with sufficient certainty. In neither analysis did CK20, CA125, or CA19.9 emerge as discriminatory parameters. Based on the same data, an intuitive flow chart was constructed with which 129 of 157 cases could be classified (only one falsely) without further statistical analysis. The five metastases with an at first unknown primary could, according to the follow-up, all be classified correctly with high PP. Most ovarian carcinomas, including the mucinous ones, can be discriminated with high probability from colonic carcinomas using a panel of three antibodies directed against CEA, cytokeratin 7, and vimentin.

Uterine carcinosarcoma is derived from a single stem cell: an in vitro study

Expression of intermediate filaments (IFs) has been suggested to be a reliable marker for differentiating epithelial and non-epithelial tumors. Moreover, the c-erbB-2 and p53 genes are considered to be involved relatively early in the process of human carcinogenesis. In order to elucidate the origin of uterine carcinosarcomas, we analyzed IF, c-erbB-2 and p53 expression in and the ultrastructural characteristics of clones derived from a human uterine-carcinosarcoma cell line, EMTOKA. The expression of IFs and other proteins in the EMTOKA clones was identical to that in the EMTOKA cell line. It and its 7 clones all expressed cytokeratins 8, 17, 18 and 19, vimentin, epithelial membrane antigen, S-100, myoglobin, type-II collagen, alpha-smooth-muscle actin, placental alkaline phosphatase and epidermal-growth-factor receptor. The c-erbB-2 and p53 expression levels of all the cell types of the EMTOKA cell line and its clones were the same. Interestingly, an ultrastructural study showed that the EMTOKA cell line and its clones at early and late passages possessed the characteristics of epithelial cell types without either transitional forms between the epithelial and stromal components or differentiation into sarcomatous components. The results of this study lend particular support to the combination tumor hypothesis that a precursor (stem) cell gives rise both to epithelial and to mesenchymal components during the histogenesis of uterine carcinosarcoma, the epithelial component of which appears to be dominant, suggesting that the established cell lines derived from a common stem cell.

Trichoblastoma and basal cell carcinoma are neoplasms with follicular differentiation sharing the same profile of cytokeratin intermediate filaments

Trichoblastoma and nodular basal cell carcinoma are generally held to be distinctive epithelial neoplasms with some overlapping features. We investigated 30 trichoblastomas in which the basaloid cells expressed cytokeratins (CK) CK5/6, CK14, CK17, CK19, and, in a few cells, vimentin. The cells of the periphery of small and large cysts showed the same profile. Cells lining the lumen of small cysts expressed CK14, CK17, and involucrin, and those in larger cysts showed a positivity for CK1, CK4, CK10, CK14, CK17, and involucrin. The remaining tested antibodies (CK7, CK8, CK13, CK18, CK20, alpha-smooth-muscle actin) were negative in all cases. The cells of the stroma expressed vimentin and in 22 cases, the CD34 antigen. Seventeen nodular basal cell carcinomas showed exactly the same staining pattern. Furthermore, there are striking immunohistochemical similarities between the neoplastic basaloid cells of both neoplasms and the cells of the hair germ. Therefore, trichoblastoma and nodular basal cell carcinoma cannot be distinguished by their pattern of cytokeratin expression in paraffin sections. The virtually identical cytokeratin pattern seen in trichoblastoma, basal cell carcinoma, and the developing fetal hair follicle is compelling evidence for common differentiation pathway.

Co-expression of MDR-associated markers, including P-170, MRP and LRP and cytoskeletal proteins, in three resistant variants of the human ovarian carcinoma cell line, OAW42

Variants of the human ovarian carcinoma cell line, OAW42, exhibiting low-level intrinsic resistance (OAW42-SR) and drug-induced higher-level resistance (OAW42-A1 & OAW42-A), were studied along with a sensitive clonal population (OAW42-S) which was isolated from OAW42-SR. Expression of the MDR-associated protein P-170, the more recently discovered LRP (lung resistance-related protein) and MRP (multidrug resistance-associated protein), topoisomerase II alpha and beta, GST pi and the cytoskeletal proteins, cytokeratin 8 and vimentin, were studied (using immunocytochemistry and Western blotting techniques) in conjunction with drug (doxorubicin) accumulation and subcellular distribution. Expression of mRNA for P-170, MRP, topoisomerase 11 alpha and beta and GST pi was studied using RT-PCR (reverse transcriptase polymerase chain reaction). Results indicate differential co-expression of four MDR-associated parameters (P-170, MRP, LRP and reduced topoisomerase II alpha and beta) in the OAW42-SR and OAW42-A1 variants, whereas resistance in the OAW42-A variant appeared to be mainly P-170 mediated. Comparable amounts of MRP and greater amounts of LRP were detected in the OAW42-S cells compared to the OAW42-SR variant (which showed increased resistance compared to the OAW42-S cells), but all cell lines expressed similar low-level amounts of MRP mRNA (by RT-PCR). GST pi levels did not differ markedly between variants. Increased levels of the cytoskeletal proteins were observed with increasing levels of resistance. The relative resistance of the variants, OAW42-SR and OAW42-A1, compared with OAW42-S was seen to change during increased serial passaging of the cells. There was greater drug accumulation by the sensitive OAW42-S cell line compared with that of the resistant variants, particularly the most highly resistant OAW42-A cells. Both verapamil and cyclosporin A effectively restored the accumulation defects seen in the resistant variants, cyclosporin A being the more effective of the two. Sub-cellular location of drug was predominantly in the nucleus with maximum levels seen in the sensitive OAW42-S variant and minimum levels in the most resistant OAW42-A clone.

Complexity of expression of the intermediate filaments of six new human ovarian carcinoma cell lines: new expression of cytokeratin 20

Six permanent human ovarian carcinoma cell lines (OVISE, OVTOKO, OVMANA and OVSAYO from clear cell adenocarcinoma, and OVSAHO and OVKATE from serous papillary adenocarcinoma) were established from solid tumours. The cell lines have been in culture for 5-8 years, the passage number varying from 62 to 246. Immunohistochemical analysis has shown that five of the six cell lines express at least six cytokeratin (CK) polypeptides. OVISE and OVSAYO expressed CKs 6, 7, 8, 18, 19 and 15 and/or 16. OVTOKO was positive for CKs 7, 8, 18, 19 and 15 and/or 16. OVSAHO expressed CKs 6, 7, 8, 14, 18, 19 and 15 and/or 16. OVMANA expressed CKs 6, 7, 8, 18, 19, 20 and 15 and/or 16. OVKATE expressed CKs 6, 7, 8, 13, 17, 18, 19, 20 and 15 and/or 16. The expression of CK7, additional expression of vimentin, and clinical and histopathological findings enabled us to confirm that six cell lines had been established from primary ovarian cancers. Two of the six cell lines were positive for CK20, although CK20 was not expressed in the original tumours. The heterotransplanted tumours produced by CK20-positive cells also expressed CK20. This is the first report of ovarian carcinoma cell lines that express CK20 irrespective of their histological type. CK20 has been found in all colon carcinoma cell lines, but only in the mucinous type of ovarian tumours. These new ovarian carcinoma cell lines will therefore provide a relevant experimental system for elucidating the regulatory control mechanisms of intermediate filament expression.

Immunocytochemical study of epidermal growth factor receptor, transforming growth factor alpha, and "squamous differentiation" in human endometrial carcinoma

The expression of epidermal growth factor receptor (EGFr) and transforming growth factor alpha (TGF-alpha) was compared with the presence of "squamous differentiation" (SD) visualized in various histotypes of endometrial carcinoma by using a panel of monoclonal antibodies. The results of the current study demonstrate that EGFr and TGF-alpha are present in routinely processed endometrial carcinoma. The highest positive EGFr and TGF-alpha expression was seen in the group of adenocarcinomas with SD. The more intense EGFr and TGF-alpha immunoreactivity was observed in "squamous" foci both in adenoacanthomas (AA) and in adenosquamous carcinomas (AS). These EGFr- and TGF-alpha-positive squamous areas prevalently displayed a "stratification-related" cytokeratin (CK) immunoprofile characterized by the expression of CKs 1, 4, 5, 10, 13, 14, and 16. No correlation was found between EGFr- and TGF-alpha-positive status and depth of myometrial invasion or surgical stage. These results clearly demonstrate that EGFr and TGF-alpha expression is related remarkably to endometrial carcinoma with "squamous" areas both morphologically and immunophenotypically. This specific association leads us to suggest that EGFr and TGF-alpha expression in endometrial carcinoma may be prevalently involved in the equilibrium of cell differentiation of the "squamous" foci commonly observed in this group of neoplasias.

Androgen responsiveness of the new human endometrial cancer cell line MFE-296

MFE-296 endometrial cancer cells express androgen receptors in vitro. These cells, which are tumorigenic in nude mice, are derived from a moderately differentiated human endometrial adenocarcinoma. They express vimentin and the cytokeratins 7, 8, 18, and 19. Karyotyping revealed near-tetraploidy for most of the cells. No marker chromosomes were observed. DNA analyses confirmed the genetic identity of the cell line and the patient from whom the cell line was derived. Proliferation of MFE-296 cells was inhibited by the progestin R5020 and the androgen dihydrotestosterone (DHT). The inhibition of proliferation by DHT was antagonized by the antiandrogen Casodex, demonstrating the involvement of the androgen receptor. Androgen binding was determined at 22,000 binding sites per cell using a whole-cell assay (KD = 0.05 nM) and 30 fmol/mg protein with the dextran charcoal method; 7 fmol/mg protein of progesterone receptors were found, whereas estrogen receptors were below 5 fmol/mg protein. The androgen receptor was functionally intact, as demonstrated by transfection experiments with a reporter-gene construct, containing an androgen-responsive element. In MFE-296 cells the content of the androgen receptor was up-regulated by its own ligand.

Establishment of new ovarian and colon carcinoma cell lines: differentiation is only possible by cytokeratin analysis

Two human ovarian (OV-MZ-10, OV-MZ-15) and two colon cancer cell lines (CO-MZ-5, CO-MZ-6) were newly established in permanent cell culture. These cell lines have been maintained in vitro for 5-6 years, the passage number varying from 25 to 228. They were established from ascites or solid tumours at the time of primary surgery. By clinical and histopathological judgement alone all four cell lines would have been interpreted as ovarian cancer cell lines. Morphological criteria or the expression of the tumour-associated antigens CA-125 and CEA allowed no differential diagnosis. Only the analysis of the expression of different cytokeratins and vimentin enabled us to verify the different origin of the cell lines. Ovarian cancer cell lines, in contrast to the colon cancer cell lines, are positive for the expression of cytokeratin (CK) 7 and for vimentin. CK 20 proved to be the marker with the best discrimination. CK 20 was found exclusively in the colon carcinoma cell lines, but not in the ovarian carcinoma cell lines. The evaluation of cytokeratin expression is a helpful diagnostic modality in differentiating between adenocarcinoma cell lines derived from ovarian and colon tumours.

Demonstration of cytokeratin intermediate filaments in oocytes of the developing and adult human ovary

The intermediate filaments (IF) present in the various cells of human ovaries were studied by immunolocalization using antibodies to cytokeratins (CKs), vimentin, desmin and alpha-smooth muscle (alpha-SM) actin. Oocytes revealed a single paranuclear aggregate, which reacted with antibodies to CKs 8, 18 and 19 both in adult and fetal ovaries. The existence of this aggregate was also documented by electron microscopy. Ovarian surface epithelium and granulosa cells consistently coexpressed CKs 8, 18, 19 and vimentin. During follicle maturation vimentin remained unchanged in the granulosa layer while CKs content decreased, showing variation in the amount and distribution of the different CK-types. Thecal cells of secondary and mature follicles showed alpha-SM actin positivity. These contractile fibres increased in mature follicles. Ordinary fibrous stromal cells showed isolated cells which were desmin and alpha-SM actin positive. A similar pattern of IF expression and distribution existed in all stages of development in fetal and embryonic ovaries. These results indicate that CKs are present in human oocytes and that the coexpression of vimentin and CKs can be regarded as a peculiar feature of all ovarian cell types except oocytes and ordinary stromal cells. Contractile properties have been documented associated with a modification in expression of IF proteins. This is likely to represent an integral part of folliculogenesis along with the functional hormone-dependent changes.

DNA-cytophotometry and immunocytochemistry in ovarian tumours of borderline malignancy and related peritoneal lesions

A total of 34 surgical specimens, obtained from 13 patients with ovarian tumours of borderline malignancy (OTBM), were investigated by conventional histology, immunocytochemistry and DNA cytophotometry. The lesions were obtained by primary ovarian surgery or second-look procedures and altogether comprised 19 (single and bilateral) OTBM, 8 cases of endosalpingiosis, 4 in situ and 2 invasive peritoneal implants and 1 overt adenocarcinoma. The morphological findings were related to follow-up data, which showed neoplasms with clinically malignant behaviour in 2 patients. The histology of the extra-ovarian manifestations was not associated with their immunocytochemical properties or with their DNA content. There were no correlations between the evolution of disease and microscopical features but the clinical course appeared to be linked to the DNA content of the extra-ovarian lesions, which was of greater prognostic importance than DNA ploidy of the ovarian tumours. Recurrence-free survival was noted in all 5 patients with diploid or euploid extra-ovarian proliferations, while the 2 clinically malignant cases fell into the group of 3 patients with noneuploid or aneuploid specimens. DNA estimations may be a methodology which increases the prognostic value of second-look procedures in OTBM patients.

Morphological, immunohistochemical and biochemical characterization of 6 newly established human ovarian carcinoma cell lines

Six permanent human tumor cell lines (OV-MZ-1 to 6) were established from 6 patients with serous adenocarcinomas of the ovary. These cell lines were derived from both solid tumors and ascites, from pre-treated and untreated patients, and are available over a range of in vitro passage numbers. The tumor cells grow as monolayers and develop foci of "piled-up' cells in confluent cultures. Flow cytophotometry showed that all the lines exhibited DNA hyperdiploidy with DNA tetraploidy in one cell line and DNA aneuploidy in the other cell lines. The mean population doubling time ranged from 24 to 52 hr. Transmission electron microscopy demonstrated that the tumor cells of all cell lines exhibited features of epithelial differentiation such as desmosomes and intracellular gland-like lumina. Immunocytochemical analysis showed that the co-expression of cytokeratins and vimentin, which is a feature of ovarian serous cystadenocarcinomas in situ, was fully preserved in the majority of cell lines. The main cytokeratin polypeptides expressed were numbers 7, 8, 17, 18 and 19. The tumor-associated antigen CA-125, but not CEA, was shed in the culture supernatant. This was in accordance with FACScan analysis of the cell lines and the level of CA-125 and CEA in the patients' serum. The estrogen and progesterone receptors were negative both in the cell lines and in the original tumors. These new ovarian carcinoma cell lines will be valuable models for further investigations into a variety of biological properties.

Co-localization of vimentin and cytokeratins in M-cells of rabbit gut-associated lymphoid tissue (GALT)

The occurrence of cytokeratins, vimentin, and desmin in the dome epithelia and adjacent non-dome epithelia in four locations of gut-associated lymphoid tissues (GALT) of adult and newborn rabbits (Peyer's patches, sacculus rotundus, caecal lymphoid patches and appendix) was studied with monoclonal antibodies, using the indirect immunoperoxidase technique. In all locations investigated in adult animals, antibodies specific for vimentin labelled (1) M-cells, which engulf intra-epithelial lymphocytes, (2) columnar epithelial cells at the base of the domes lacking an apparent contact with lymphocytes ("immature" M-cells), and (3) flat cells, which lie in the lamina propria under the dome epithelium, and which line the basal lamina with thin cytoplasmic processes. In newborn rabbits, columnar epithelial cells resembling the immature M-cells of adults were selectively stained with vimentin antibodies. In M-cells, the strongest immunoreactivity was present in the perinuclear region and close to the pocket membrane, whereas the most apical and most basal parts of the cytoplasm showed no vimentin-immunoreactivity. Enterocytes in the dome epithelium and in the non-dome epithelium were vimentin-negative. M-cells and enterocytes bound antibodies against cytokeratin peptides 18 and 19 in adult and newborn animals. Compared with enterocytes, M-cells showed less intense staining for cytokeratins. Dome epithelia and no-dome epithelia did not contain desmin-immunoreactive cells. The results suggest that vimentin is a sensitive marker for M-cells in rabbit GALT.