Stratification of urinary bladder carcinoma based on immunohistochemical expression of CK5, CK14 and CK20.

Molecular subtyping of urothelial carcinoma (UC) is similar to that of breast cancer and is based on the developmental biology approach. The aim of the present study is to assess the prognostic impact of CK5, CK14, and CK20 expression in urinary bladder cancer (UBC) with the potential to stratify them into different subtypes. The current study examined the immunohistochemical expression of CK5, CK14, and CK20 in 90 specimens of UBC. CK5 was expressed in 81.1% of the cases and was significantly associated with old age, muscle invasion, presence of bilharziasis, and tendency for poor overall survival. CK20 was expressed in 47.8% of the cases and was associated with nonmuscle invasion and pure UC while 50% of the cases expressed CK14 that were associated with muscle invasion and perineural invasion. Most squamous cell carcinoma and those associated with bilharziasis were belonged to Ck5+/CK20- subgroup while pure UC and those lacked bilharziasis were located in the Ck5+/CK20+ subgroup. The basal group (Ck5+/CK14+/CK20-) showed high proliferative features compared to the intermediate group (Ck5+/CK14-/CK20-). Generally, presence of CK5 is associated with adverse features especially in the group lacking CK20; however, basal and intermediate subgroups share CK5 expression but they show different proliferative capacities, so their distinction by CK14 is helpful.

Murine HPV16 E7-expressing transgenic skin effectively emulates the cellular and molecular features of human high-grade squamous intraepithelial lesions.

Currently available vaccines prevent HPV infection and development of HPV-associated malignancies, but do not cure existing HPV infections and dysplastic lesions. Persistence of infection(s) in immunocompetent patients may reflect induction of local immunosuppressive mechanisms by HPV, providing a target for therapeutic intervention. We have proposed that a mouse, expressing HPV16 E7 oncoprotein under a Keratin 14 promoter (K14E7 mice), and which develops epithelial hyperplasia, may assist with understanding local immune suppression mechanisms that support persistence of HPV oncogene-induced epithelial hyperplasia. K14E7 skin grafts recruit immune cells from immunocompetent hosts, but consistently fail to be rejected. Here, we review the literature on HPV-associated local immunoregulation, and compare the findings with published observations on the K14E7 transgenic murine model, including comparison of the transcriptome of human HPV-infected pre-malignancies with that of murine K14E7 transgenic skin. We argue from the similarity of i) the literature findings and ii) the transcriptome profiles that murine K14E7 transgenic skin recapitulates the cellular and secreted protein profiles of high-grade HPV-associated lesions in human subjects. We propose that the K14E7 mouse may be an appropriate model to further study the immunoregulatory effects of HPV E7 expression, and can facilitate development and testing of therapeutic vaccines.

Availability of immunocytochemistry using cocktail antibody targeting p63/cytokeratin14 for the differential diagnosis of fibroadenoma and ductal carcinoma in situ in fine needle aspiration cytology of the breast.

OBJECTIVE: The differential diagnosis of fibroadenoma (FA) and ductal carcinoma in situ (DCIS) has been problematic in fine needle aspiration biopsy (FNAC) because it has been difficult to differentiate between the "large epithelial clusters" associated with FA and those associated with DCIS. The purpose of this study was to prospectively validate the usefulness of immunocytochemical staining using cocktail antibody targeting p63/CK14 in the differential diagnosis of FA and DCIS. MATERIALS AND METHODS: Twenty patients diagnosed as having an uncertain malignant potential (indeterminate) for breast cancer on the basis of a FNAC finding were selected randomly: ten patients with FA and ten with DCIS. The cover glass on a specimen stained with the Papanicolaou stain on a glass slide was peeled off, and the specimen was restained by immunocytochemical staining of cocktail antibody targeting p63 and CK14. RESULTS: Six of the twenty patients were CK14-immunopositive: FA, 6; DCIS, 0. The remaining patients were CK14-immunonegative: FA, 4; DCIS, 10. The number of CK14-immunopositive DCIS patients was significantly different from that of FA patients (P=.0054). Eight out of the twenty patients were p63-immunopositive: FA, 8; DCIS, 0. The remaining patients were p63-immunonegative: FA, 2; DCIS, 10. The number of p63-immunopositive DCIS patients was significantly different from that of FA patients (P=.0004). CONCLUSIONS: Immunocytochemical staining using cocktail antibody targeting p63/CK14 was useful for the differential diagnosis of FA and DCIS in FNAC of the breast.

Epithelial cell migration requires the interaction between the vimentin and keratin intermediate filaments.

Epithelial migration plays a central role in development, wound repair and tumor metastasis, but the role of intermediate filament in this important event is unknown. We showed recently that vimentin coexists in the same cell with keratin-KRT14 at the leading edge of the migrating epidermal cells, and knockdown of vimentin impaired colony growth. Here we demonstrate that vimentin co-localizes and co-immunoprecipitates with keratin-KRT14, and mutations in the -YRKLLEGEE- sequence of vimentin significantly reduced migration of the keratinocytes. Our data demonstrates that keratinocyte migration requires the interaction between vimentin and keratins at the -YRKLLEGEE- sequence at the helical 2B domain of vimentin. These findings have broad implications for understanding the roles of vimentin intermediate filaments in normal and neoplastic epithelial cells.

Coordinate expression of cytokeratins 7 and 14, vimentin, and Bcl-2 in canine cutaneous epithelial tumors and cysts.

Forty-seven canine cutaneous epithelial tumors and cysts were examined to determine coordinate expression of cytokeratins 7 (CK7) and 14 (CK14), vimentin, and Bcl-2 using commercially available antibodies. Within non-affected normal skin adjacent to tumors or cysts, CK7 expression was observed in luminal cells in apocrine glands; CK14 expression was observed in the stratum basale, stratum spinosum, stratum granulosum, basal layer of outer root sheath, sebaceous glands, and myoepithelial cells of apocrine glands; vimentin expression was observed in dermal papilla and scattered non-epithelial cells within the epidermis; and Bcl-2 expression was observed in scattered non-epithelial cells in the epidermis and some apocrine glands. The pattern of expression of CK7 and CK14 in cases of adenocarcinoma of the apocrine gland of the anal sac (CK7+/CK14-) and hepatoid gland tumors (CK7-/CK14+) may prove useful for diagnostic purposes. Loss of expression of CK14 and vimentin, identifying myoepithelial cells, was observed in apocrine and ceruminous adenocarcinomas. Differences in patterns of expression of Bcl-2 were observed between infundibular keratinizing acanthomas compared to trichoepitheliomas.

The clinical use of a P63/cytokeratin7/18/cytokeratin5/14 antibody cocktail in diagnostic breast pathology.

An antibody cocktail directed against p63, cytokeratin (CK)5/14, and CK7/18 is reported to be useful in distinguishing noninvasive from invasive breast lesions and for the characterization of intraductal epithelial proliferations. However, limited studies evaluate its use in clinical practice. A retrospective review of breast material at a university medical center identified cases that were immunostained with the above antibody cocktail. Additional p63 immunostaining alone was performed to further determine the utility of the antibody cocktail in the evaluation of invasion. Of 50 breast cases identified, the antibody cocktail was used to confirm or exclude invasion in 44 (88%). Twenty-two (50%) of these had easily identifiable p63/CK5/14-positive myoepithelial cells, whereas the remainder lacked such staining, confirming the diagnosis of invasive carcinoma. In 27 cases with available diagnostic material for additional p63 immunostaining, the cocktail better highlighted myoepithelial cells by staining nuclei and cytoplasm. Easier identification of invasion was also facilitated by CK7/18 expression in invasive foci, especially those composed of single cells. Ten cases were immunostained to help determine the nature of an intraductal proliferation. The cocktail demonstrated a mosaic staining pattern of both CK7/18- and CK5/14-positive epithelial cells in 3 (30%) cases consistent with usual hyperplasia; homogenous CK7/18 expression in the remaining cases supported the diagnosis of atypical ductal hyperplasia or carcinoma in situ. In summary, the p63/CK7/18/CK5/14 cocktail stain appears to be a useful tool in diagnostic breast pathology, in the evaluation of possible invasion, particularly in the setting of minute foci of invasion as well as in epithelial proliferations.

Id4 protein is highly expressed in triple-negative breast carcinomas: possible implications for BRCA1 downregulation.

BRCA1 germline mutation carriers usually develop ER, PR and HER2 negative breast carcinoma. Somatic BRCA1 mutations are rare in sporadic breast cancers, but other mechanisms could impair BRCA1 functions in these tumors, particularly in triple-negative breast carcinomas (TNBCs). Id4, a helix-loop-helix DNA binding factor, blocks BRCA1 gene transcription in vitro and could downregulate BRCA1 in vivo. We compared Id4 immunoreactivity in 101 TNBCs versus 113 non-TNBCs, and correlated the results with tumor morphology and immunoreactivity for CK5/6, CK14, EGFR, and androgen receptor (AR). Id4 was present in 76 out of 101 (75 %) TNBCs: 40 (40 %) TNBCs displayed Id4 positivity in >50 % of neoplastic cells, 23 (23 %) in 5-50 %, and 13 (13 %) in <5 %. In contrast, only 6 (5 %) of 113 non-TNBCs showed focal Id4 positivity, limited to fewer than 5 % of the tumor (p < 0.0001). Id4 expression significantly associated with high histologic grade (p = 0.0002) and mitotic rate (p = 0.006). Id4 decorated all 12 TNBCs with large central acellular zone of necrosis in our series, with positive staining in 10-90 % of the cells. Id4 signal strongly correlated with cytokeratin CK14 reactivity (p < 0.0001), but not with CK5/6 and EGFR. All apocrine carcinomas in our series were positive for AR and most for EGFR, but they were negative for CK5/6, CK14, and Id4, with only two exceptions. Our results document substantial expression of Id4 in most TNBCs, which could result in functional downregulation of BRCA1 pathways in these tumors.

Integrating chemistry and immunology in allergic contact dermatitis: more questions than answers?

In this issue, Simonsson and colleagues shed light on the chemical mechanisms determining hapten formation in the skin, which precede the elicitation of an antigen-specific immune response in allergic contact dermatitis. Combining fluorescence microscopy, proteomics, and mass spectrometry, the investigators identified keratins K5 and K14, particularly cysteine 54 of K5, in the human basal epidermal layer as the major molecular targets of caged thiol-reactive fluorescent haptens (i.e., bromobimanes). Anti-keratin antibody responses in mice exposed to bromobimanes suggest the generation of immunogenic epitopes by cysteine-reactive haptens. Although many issues await further investigation, Simonsson and co-workers' observations advance our understanding of the molecular basis of hapten-protein complex formation in skin.

Thymic microenvironment reconstitution after postnatal human thymus transplantation.

A functional thymus develops after cultured thymus tissue is transplanted into subjects with complete DiGeorge anomaly. To gain insight into how the process occurs, 7 post-transplantation thymus biopsy tissues were evaluated. In 5 of 7 biopsies, the thymus appeared to be predominantly cortex with thymocytes expressing cortical markers. Unexpectedly, the epithelium expressed both cortical [cortical dendritic reticulum antigen 2 (CDR2)] and medullary [cytokeratin (CK) 14] markers. Early medullary development was suggested by epithelial cell adhesion molecule (EpCAM) reactivity in small areas of biopsies. Two other biopsies had distinct mature cortex and medulla with normal restriction of CK14 to the medulla and subcapsular cortex, and of CDR2 to cortex. These data are consistent with a model in which thymic epithelium contains CK14+ "progenitor epithelial cells". After transplantation these cells proliferate as CK14+CDR2+ thymic epithelial cells that are associated with cortical thymocytes. Later these cells differentiate into distinct cortical and medullary epithelia.

Rapid multiplex immunohistochemistry using the 4-antibody cocktail YANA-4 in differentiating primary adenocarcinoma from squamous cell carcinoma of the lung.

The current Food and Drug Administration-approved standard treatment for non-small cell carcinomas consists of carboplatin/taxol/avastin. However, nowadays more specialized protocols, depending on tumor subtype, are being used for lung cancer patients. Therefore, accurate differentiation between adenocarcinoma and squamous cell carcinoma is essential for the selection of appropriate therapies. We designed a rapid multiplex immunostaining method using a novel 4-antibody cocktail, YANA-4. This antibody cocktail consists of the following monoclonal antibodies: rabbit for thyroid transcription factor 1(TTF-1), mouse for napsin A, mouse l for p63, and rabbit for CK14. All procedures can be completed within 3 hours. This method labels the nuclei of adenocarcinomas as brown with TTF-1, and cytoplasm as blue with napsin A. Squamous cell carcinomas could be differentiated from adenocarcinomas with an inverse staining pattern: blue nuclei with p63 and brown cytoplasm with CK14. In this study, 97.4% (38 of 39) of adenocarcinomas showed brown nuclei (TTF-1) and/or blue cytoplasm (napsin A), with 4 cases showing positivity only for brown nuclei (TTF-1) and 1 case only for blue cytoplasm (napsin A). None of the squamous cell carcinoma cases showed these staining patterns. Positivity for blue nuclei (p63) and/or brown cytoplasm (CK14) was detected in 100% (25 of 25) of squamous cell carcinomas, with 1 case showing positivity only for brown cytoplasm (CK14) and 2 cases only for blue nuclei (p63). None of the adenocarcinoma cases showed these patterns. This rapid immunohistochemical method can thus be considered highly specific and sensitive for differentiating adenocarcinomas and squamous cell carcinomas.

Caged fluorescent haptens reveal the generation of cryptic epitopes in allergic contact dermatitis.

Allergic contact dermatitis (ACD) is the most prevalent form of human immunotoxicity. It is caused by skin exposure to haptens, i.e., protein-reactive, low-molecular-weight chemical compounds, which form hapten-protein complexes (HPCs) in the skin, triggering the immune system. These immunogenic HPCs are elusive. In this study a series of thiol-reactive caged fluorescent haptens, i.e., bromobimanes, were deployed in combination with two-photon fluorescence microscopy, immunohistochemistry, and proteomics to identify possible hapten targets in proteins in human skin. Key targets found were the basal keratinocytes and the keratins K5 and K14. Particularly, cysteine 54 of K5 was found to be haptenated by the bromobimanes. In addition, elevated levels of anti-keratin antibodies were found in the sera of mice exposed to bromobimanes in vivo. The results indicate a general mechanism in which thiol-reactive haptens generate cryptic epitopes normally concealed from the immune system. In addition, keratinocytes and keratin seem to have an important role in the mechanism behind ACD, which is a subject for further investigations.

Histological diversity in basaloid squamous cell carcinoma of the esophagus.

Basaloid squamous cell carcinoma of the esophagus (BSCCE) is a distinct variant of esophageal cancer. This study investigated histopathological variations of BSCCE. Thirty-eight surgical and two endoscopically resected specimens of BSCCE were examined. Histological features were classified into five components: solid nest (SN), microcyst and/or trabecular nest (MT), ductal differentiation (DD), cribriform pattern (CP), and an invasive squamous cell carcinoma (SCC) component. The immunohistochemical phenotypes of each component were examined using antibodies against cytokeratin (CK) 7, CK14, and alpha smooth muscle actin (SMA). SN, MT, DD, CP, and SCC were present in 95.0, 97.5, 27.5, 32.5, and 82.5% of the cases, respectively, and combinations of SN & MT, SN & DD, SN, MT & DD, SN, MT & CP, and SN, MT, DD & CP were found in 50.0, 2.5, 10.0, 17.5, and 15.0%, respectively. All the intraepithelial lesions observed in 18 (45.0%) cases were SCC. Immunoreactivity for CK7, CK14, and SMA was seen in 10.5, 86.8, and 18.4% of SN; 30.8, 97.4, and 38.5% of MT; 54.5, 100.0, and 54.5% of DD; 7.7, 76.9, and 23.1% of CP; and 6.1, 97.0, and 0.0% of SCC, respectively. CK14 immunoreactivity was seen in the periphery of most of the SN component. CK7, CK14, and SMA immunoreactivity was seen in the inner layer, all layers, and the outer layer of DD, respectively. MT and CP showed partial peripheral positivity for CK14 and SMA in microcystic, trabecular, and cribriform-like pseudoglandular structures. BSCCE demonstrates various histopathological and immunohistochemical features including a ductal and cribriform growth pattern.

TPA induction leads to a Th17-like response in transgenic K14/VEGF mice: a novel in vivo screening model of psoriasis.

Psoriasis is a common chronic inflammatory skin disease, characterized by epidermal hyperplasia, immune cell infiltration, increased dermal angiogenesis and local up-regulation of a variety of inflammatory mediators. Psoriasis is thought to be driven primarily by CD4(+) T cells with a T(h)1 and/or T(h)17 phenotype. Transgenic keratin 14 (K14)/vascular endothelial growth factor (VEGF) mice have previously been reported to develop a psoriasis-like phenotype. The aim of this study was to further characterize the model for validation as an in vivo screening model of psoriasis. Inflammation was induced in the ear skin with five topical applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) and a significantly increased inflammation was found in TPA-induced K14/VEGF transgenic animals compared with wild-type mice. The amount of VEGF in the ear tissue was significantly elevated resulting in increased dermal angiogenesis. Furthermore, intense epidermal hyperplasia, CD3(+) infiltration and significantly increased amounts of (TNF) tumor necrosis factor alpha, IL-1 beta, IL-6, IL-12/23p40, IL-12p70, IL-22 and IL-17 were detected in the inflamed ear skin. This cytokine profile strongly suggests a T(h)17-mediated inflammation. All findings were a result of induced over-expression of VEGF. Topical treatment with betamethasone-17-valerate (BMS) significantly reduced ear skin inflammation and epidermal hyperplasia and also decreased the CD3(+) infiltration. In conclusion, the TPA-induced phenotype in K14/VEGF animals displayed several features of psoriasis, including a T(h)17 cytokine profile and a chronic-like progression, and can be used as an in vivo screening model of psoriasis.