Cytokeratin 7 and 19 expression in oropharyngeal and oral squamous cell carcinoma.

PURPOSE: The precise etiopathogenesis of human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC), and reasons for predilection for crypt epithelium, remain uncertain. The purpose of this study is to investigate the interaction between HPV and specific cytokeratins 7 (CK7) and 19 (CK19) in crypt epithelium. METHODS: This is a retrospective cohort study of patients presenting between 1999 and 2015 at a tertiary referral center. CK7 and CK19 positivity and H Scores were determined by immunohistochemistry. Disease-specific and overall survival rates were analyzed. RESULTS: There were 253 patients presenting with OPSCC (134), squamous cell carcinoma (SCC) of unknown primary site (22), and oral tongue SCC (97). Primary tumor CK7 and CK19 positivity and H Scores were significantly higher in HPV-positive OPSCC than HPV-negative OPSCC and oral tongue SCC. Higher CK19 Scores, but not CK7 Scores, were also seen in regional metastases from HPV-positive OPSCC than other sites. No impact on disease-specific or overall survival was identified on multivariate analysis. CONCLUSION: The increased expression of CK7 and CK19 in HPV-positive OPSCC compared to HPV-negative disease supports the theory for a role for these cytokeratins in the etiopathogenesis of HPV-related OPSCC.

Trichilemmal Cysts With Divergent Ductal Differentiation: A Series of 4 Cases.

ABSTRACT: Trichilemmal cysts are common clonal tumors with a predilection for the scalp. They are composed of an outer epithelial wall resembling the outer root sheath in the isthmus of the hair follicle and a central core of compact keratin. Sweat duct differentiation is exceptional with only one convincing case reported to date. Here, we sought to characterize the clinicopathological characteristics of sweat duct differentiation in trichilemmal cysts. We reviewed all cases of trichilemmal cyst diagnosed at our institution between 2008 and 2019. Ductal structures were found in 4 of 411 cases (0.97%). Subjects included 2 male and 2 female patients with a median age of 37.5 years (range 34-55). The ducts were lined by attenuated epithelial cells and immunoreactive for polyclonal carcinoembryonic antigen and cytokeratin 7. Ductal differentiation involved a median of 7.5% (range 1%-50%) of the cyst wall. All 4 cases were from the scalp and treated with local excision. No recurrence was identified with a median follow-up period of 1.5 years (range 1-12 years). In summary, sweat duct differentiation in trichilemmal cysts is rare but likely under recognized. Conceptually, we suggest it represents a type of divergent cellular differentiation within a clonal neoplasm rather than a retention cyst or hybrid cyst.

A combination of the immunohistochemical markers CK7 and SATB2 is highly sensitive and specific for distinguishing primary ovarian mucinous tumors from colorectal and appendiceal metastases.

Primary ovarian mucinous tumors can be difficult to distinguish from metastatic gastrointestinal neoplasms by histology alone. The expected immunoprofile of a suspected metastatic lower gastrointestinal tumor is CK7-/CK20+/CDX2+/PAX8-. This study assesses the addition of a novel marker SATB2, to improve the diagnostic algorithm. A test cohort included 155 ovarian mucinous tumors (105 carcinomas and 50 borderline tumors) and 230 primary lower gastrointestinal neoplasms (123 colorectal adenocarcinomas and 107 appendiceal neoplasms). All cases were assessed for SATB2, PAX8 CK7, CK20, and CDX2 expression on tissue microarrays. Expression was scored in a 3-tier system as absent, focal (1-50% of tumor cells) and diffuse ( >50% of tumor cells) and then categorized into either absent/present or nondiffuse/diffuse. SATB2 and PAX8 expression was further evaluated in ovarian tumors from an international cohort of 2876 patients (expansion cohort, including 159 mucinous carcinomas and 46 borderline mucinous tumors). The highest accuracy of an individual marker in distinguishing lower gastrointestinal from ovarian mucinous tumors was CK7 (91.7%, nondiffuse/diffuse cut-off) followed by SATB2 (88.8%, present/absent cut-off). The most effective combination was CK7 and SATB2 with accuracy of 95.3% using the 3-tier interpretation, absent/focal/diffuse. This combination outperformed the standard clinical set of CK7, CK20 and CDX2 (87.5%). Re-evaluation of outlier cases confirmed ovarian origin for all but one case. The accuracy of SATB2 was confirmed in the expansion cohort (91.5%). SATB2 expression was also detected in 15% of ovarian endometrioid carcinoma but less than 5% of other ovarian histotypes. A simple two marker combination of CK7 and SATB2 can distinguish lower gastrointestinal from ovarian primary mucinous tumors with greater than 95% accuracy. PAX8 and CDX2 have value as second-line markers. The utility of CK20 in this setting is low and this warrants replacement of this marker with SATB2 in clinical practice.

Histological processing of un-/cellularized thermosensitive electrospun scaffolds.

Histological processing of thermosensitive electrospun poly(ε-caprolactone)/poly(L-lactide) (PCL/PLA) scaffolds fails, as poly(ε-caprolactone) (PCL) is characterized by its low-melting temperature (Tm = 60 °C). Here, we present an optimized low-temperature preparation method for the histological processing of un-/cellularized thermosensitive PCL/PLA scaffolds.Our study is aimed at the establishment of an optimized dehydration and low-melting-point paraffin-embedding method of electrospun PCL/PLA scaffolds (un-/cellularized). Furthermore, we compared this method with (a) automatized dehydration and standard paraffin embedding, (b) gelatin embedding followed by automatized dehydration and standard paraffin embedding, (c) cryofixation, and (d) acrylic resin embedding methods. We investigated pepsin and proteinase K antigen retrieval for their efficiency in epitope demasking at low temperatures and evaluated protocols for immunohistochemistry and immunofluorescence for cytokeratin 7 (CK7) and in situ padlock probe technology for beta actin (ACTB). Optimized dehydration and low-melting-point paraffin embedding preserved the PCL/PLA scaffold, as the diameter and structure of its fibers were unchanged. Cells attached to the PCL/PLA scaffolds showed limited alterations in size and morphology compared to control. Epitope demasking by enzymatic pepsin digestion and immunostaining of CK7 displayed an invasion of attached cells into the scaffold. Expression of ACTB and CK7 was shown by a combination of mRNA-based in situ padlock probe technology and immunofluorescence. In contrast, gelatin stabilization followed by standard paraffin embedding led to an overall shrinkage and melting of fibers, and therefore, no further analysis was possible. Acrylic resin embedding and cyrofixation caused fiber structures that were nearly unchanged in size and diameter. However, acrylic resin-embedded scaffolds are limited to 3 µm sections, whereas cyrofixation led to a reduction of the cell size by 14% compared to low-melting paraffin embedding. The combination of low-melting-point paraffin embedding and pepsin digestion as an antigen retrieval method offers a successful opportunity for histological investigations in thermosensitive specimens.

Low-grade oncocytic tumour of kidney (CD117-negative, cytokeratin 7-positive): a distinct entity?

AIM: To describe a group of distinct low-grade oncocytic renal tumours that demonstrate CD117 negative/cytokeratin (CK) 7-positive immunoprofile. METHODS AND RESULTS: We identified 28 such tumours from four large renal tumour archives. We performed immunohistochemistry for: CK7, CD117, PAX8, CD10, AMACR, e-cadherin, CK20, CA9, AE1/AE3, vimentin, BerEP4, MOC31, CK5/6, p63, HMB45, melan A, CD15 and FH. In 14 cases we performed array CGH, with a successful result in nine cases. Median patient age was 66 years (range 49-78 years) with a male-to-female ratio of 1:1.8. Median tumour size was 3 cm (range 1.1-13.5 cm). All were single tumours, solid and tan-brown, without a syndromic association. On microscopy, all cases showed solid and compact nested growth. There were frequent areas of oedematous stroma with loosely arranged cells. The tumour cells had oncocytic cytoplasm with uniformly round to oval nuclei, but without significant irregularities, and showed only focal perinuclear halos. Negative CD117 and positive CK7 reactivity were present in all cases (in two cases there was focal and very weak CD117 reactivity). Uniform reactivity was found for PAX8, AE1/AE3, e-cadherin, BerEP4 and MOC31. Negative stains included CA9, CK20, vimentin, CK5/6, p63, HMB45, Melan A and CD15. CD10 and AMACR were either negative or focally positive; FH was retained. On array CGH, there were frequent deletions at 19p13.3 (seven of nine), 1p36.33 (five of nine) and 19q13.11 (four of nine); disomic status was found in two of nine cases. On follow-up (mean 31.8 months, range 1-118), all patients were alive with no disease progression. CONCLUSION: Low-grade oncocytic tumours that are CD117-negative/CK7-positive demonstrate consistent and readily recognisable morphology, immunoprofile and indolent behaviour.

The role of immunohistochemical staining with CK7 in the differential diagnosis of autoimmune hepatitis.

INTRODUCTION: Although the immunohistochemical staining with cytokeratin 7 (CK7) is an adjuvant method for identifying various components of the intrahepatic biliary system, the expression of CK7 does not occur in hepatocytes. In the literature, some studies suggest that a group of cells having dual morphologic and immunophenotypic characteristics of bile duct epithelium and hepatocytes, referred to as progenitor stem cells, was stained positive with CK7. MATERIALS AND METHODS: In this study, we examined a total of 219 cases diagnosed with autoimmune hepatitis, chronic hepatitis B, chronic hepatitis C, and primary biliary cholangitis between 2005 and 2017 in Uludag University, Faculty of Medicine, Department of Medical Pathology. RESULTS: The comparisons of AIH cases with HepB, HepC and PBC cases demonstrated that the immunoreactivity to CK7 was significantly higher in the AIH group (p < 0.005) compared to the groups of HepB and HepC, whereas no significant differences were found between the AIH and PBC groups. CONCLUSIONS: In our study, it was concluded that the immunoreactivity to CK7 could be used as an adjuvant treatment to the clinicopathologic assessment in distinguishing between the AIH cases and chronic viral hepatitis. However, since CK7 immunoreactive hepatocytes were widely detected also in patients with chronic viral hepatitis, and there was no statistically significant difference between the PBC and AIH cases, it has been established that the inclusion of CK7 immunoreactivity into the diagnostic histopathological criteria for AIH would not be convenient (Tab. 1, Fig. 1, Ref. 22).

[Combined application of immunohistochemical markers to identify pathologic subtypes of ampullary carcinoma and its clinical significance].

Objective: To investigate the expression of immunomarkers CK7, CK20, CK17, CDX2, MUC1 and MUC2 in primary adenocarcinoma of the ampulla of Vater, to explore the role of these markers in the histopathologic subclassification of ampullary carcinoma; and to provide biologic basis for precision treatment of patients with different types of ampullary carcinoma. Methods: Forty-two cases of primary ampullary carcinoma were collected at Peking University People's Hospital, from 2012 to 2018 year. There were 22 males and 20 females. Aged range 42 to 88 years old, with mean aged (62±11) years. Among the patients, 6 was high differentiation, 19 median differentiation, and 17 low differentiation. Immunohistochemical studies on the expression of CK7, CK20, CK17, CDX2, MUC1 and MUC2 were performed in 42 cases of primary ampullary carcinoma. The relationship between different ampullary carcinoma subtypes and clinicopathologic survival data was analyzed using SPSS 16.0 statistical software. Results: Three histopathologic subtypes were observed. Among 42 cases, 8(19.0%)were classified as intestinal subtype, which showed a positive expression rate of 8/8 for both CK20 and CDX2, and 5/8 for MUC2. Both CK7 and CK17 were weakly expressed in one case (1/8). No expression was observed for MUC1 in this subtype. Twenty-two (52.4%,22/42) cases were classified as pancreaticobiliary subtype, which showed a positive expression rate of 100.0%(22/22) for both CK7 and MUC1, and 90.9% (20/22) for CK17. No expression was observed for CK20, CDX2 and MUC2.The remaining 12 (28.6%) cases were classified as mixed subtype, which showed variable expression patterns. The expression frequencies of these 6 immunomarkers in different subtypes of ampullary carcinoma did not correlate with various clinicopathologic factors such as patient gender and age, tumor size, histologic differentiation, pancreatic and bile duct invasion, or the depth of duodenal invasion. However, stage Ⅲ+Ⅳ diseases were more commonly seen in pancreaticobiliary type (63.6%,14/22) than intestinal type (2/8) and mixed type (3/9; χ(2)=6.508, P=0.039). Follow-up data showed a trend of better survival rate for patients with intestinal subtype than those with mixed and pancreaticobiliary subtypes. Conclusions: Ampullary carcinoma can be subclassified into three different subtypes using a panel of six immunomarkers, especially for the identification of subtypes of poorly differentiated carcinoma. CK7, CK17 and MUC1 are major markers of pancreaticobiliary subtype, whereas CK20, CDX2 and MUC2 are useful markers for intestinal subtype. The mixed subtype variably expresses these markers. The prognosis of patients with intestinal subtype appears better than that of pancreaticobiliary and mixed subtypes. Accurate subtyping of ampullary carcinoma is clinically important to patient management and prognosis assessment.

[Ovarian Sertoli-Leydig tumor: A tricky tumor]. / La tumeur de Sertoli-Leydig ovarienne : une tumeur qui peut être piégeuse.

We report the case of a 15 years old teenage girl presenting with a primary amenorrhea and hypervirilisation symptoms. The clinical assessement found a 16cm wide heterogenous ovarian mass testosteronemia and alpha-foeto protein levels were increased. On gross exam the tumor was solid and cystic, multilocular containing serous and mucinous liquids. Microscopically, there was a sertoli cells rich solid area in which the cells had a trabecular and nested organization with Leydig cells between them and there was also a cystic area made of glandular structures lined with an intestinal muco-secreting epithelium. Next to these area, there were Sertoli cells and an oedematous stroma. The immunostaining showed that the Sertoli cells expressed, among others, the inhibine and the glands expressed the cytokeratins 7 and 20. A Sertoli and Leydig cells tumor of intermediate differentiation with heterologous elements diagnostic was made. This is a rare tumor, representing less than 0.5% of ovary tumors. Well differentiated tumors are not frequent. In one third of the cases, there are hypervirilisation symptoms, the imaging exams will serve to narrow the diagnosis and to do a full work-up to establish an extension. There are several histologic sub types caracterised by the existence of retiforms structures or heterologous elements. There are no specific immunostainings, this will only help to narrow the diagnosis and rule out some hypothesis. There are no guidelines for the management of the patients, indeed each center has its own practices. Those tumors have quite a good prognosis thanks to their early diagnosis at a stade where they are still confined to the ovary.

[Low-grade eosinophilic unclassified renal cell carcinoma, a recently proposed entity in the spectrum of eosinophilic renal cells tumors: Report of one case and discussion]. / Le carcinome rénal inclassé de bas grade à cellules éosinophiles, une entité récemment proposée dans le spectre des tumeurs rénales à cellules éosinophiles : étude d'un cas et discussion.

Low-grade eosinophilic unclassified renal cell carcinoma is a rare kidney tumor recently described, not included in the WHO classification, which is very close to oncocytoma. It is unknown to most pathologists and clinicians. From a histopathological point of view, this tumor is composed of oncocytic cells arranged in a diffuse and solid pattern, without cell nests, that makes it possible to differentiate it from oncocytoma, and expresses cytokeratin 7 (CK7) heterogeneously. We report a case with a cranial vault metastasis, and present the features to differentiate this entity from oncocytoma. Furthemore, we discuss about unclassified renal cell carcinomas with oncocytic cells.

A Rare Case of CK20/CK7 Double Negative Merkel Cell Carcinoma.

The authors present a case of Merkel cell carcinoma (MCC) with unique immunohistochemical staining characteristics. A 57-year-old woman presented with a firm 0.3 cm tan papule on her left nasal-labial fold that was reportedly increasing in size and bleeding. She had a history of multiple head and neck actinic keratoses, papillary thyroid carcinoma, and a family history of an uncle with melanoma. The clinical differential diagnosis was "non-melanoma skin cancer." Histological examination showed a markedly atypical-appearing basaloid neoplasm, present mostly in the dermis, with focal pagetoid spread into the epidermis. The cells showed hyperchromatic-staining nuclei, crowding, nuclear molding, and scant cytoplasm with atypical mitoses. The findings were consistent with a malignant tumor, highly suspicious for MCC. A pancytokeratin stain was strongly positive and showed perinuclear dot-like positivity. CK20 and CK7 stains were both negative. Synaptophysin was strongly positive, chromogranin was focally positive, CD56 was weakly positive, and neurofilament was positive in a perinuclear dot-like pattern. TTF-1, PAX5, S100, and Melan-A were negative, arguing against metastatic small cell carcinoma of lung or thyroid, B-cell lymphoma, or melanoma, respectively. Although the CK20/CK7 double negativity is very unusual, the staining characteristics of this case are most consistent with a primary cutaneous MCC. Up to 10%-15% of MCCs can be CK20 negative, and those cases are typically CK7 positive. This case is unique, as a CK20/CK7 double negative case has not been previously reported; however, the diagnosis can still be rendered based on the clinical, histological, and other immunohistochemical findings.

p16INK4a, Cytokeratin 7, and Ki-67 as Potential Markers for Low-Grade Cervical Intraepithelial Neoplasia Progression.

OBJECTIVE: The aim of this study was to evaluate p16, cytokeratin 7 (CK7), and Ki-67 immunoexpressions in low-grade squamous intraepithelial lesion (LSIL), looking for differences among cases that progress to high-grade squamous intraepithelial lesion, maintain LSIL, or regress. MATERIALS AND METHODS: Sixty-six LSIL biopsies were studied. In the follow-up, a second biopsy showed 28.7% regression, 37.9% LSIL, and 33.4% progressed to high-grade squamous intraepithelial lesion. Immunostaining for these markers were performed in the first biopsy. A qualitative evaluation method was used, as well as histomorphometry, using ImageJ software. Pearson χ, Mann-Whitney, Kruskal-Wallis, and Fisher tests were used to compare the groups (P ≤ .05). A cutoff point was assessed through receiver operating characteristic curve positive cell ratio, for each marker, as progression predictors. RESULTS: The mean age of patients with and without progression was 33 and 27 years (P = .006), respectively. The qualitative evaluation indicated a tendency of progression, but without statistical significance. However, through histomorphometry, the receiver operating characteristic curve analysis showed cutoff points of 0.396, 0.345, and 0.026 for p16, CK7, and Ki-67 ratios, respectively, as predictors of progression (P = .003, .03, and .002, respectively). In a logistic regression analysis, p16, CK7, and Ki-67 positive cell ratio showed a significant correlation with progression (P = .036, .012, and .006, respectively). CONCLUSIONS: p16, CK7, and Ki-67 may represent useful biomarkers that can identify LSIL lesions that need particular attention.

Immunohistochemistry of Cytokeratin 7, Cytokeratin 20 and Thyroid Transcription Factor-1 in Metastatic Carcinoma of Cervical Lymph Node Biopsy for Identification of Pulmonary Origin in Rajavithi Hospital.

Background: One of the most powerful tools used in "the team approach in modern medicine" is immunohistochemistry, a minimally invasive investigative technique which is helpful in many respects, such as in suggesting or defining the primary site of metastatic malignant neoplasms. The panel of Cytokeratin7 (CK7), Cytokeratin20 (CK20) and Thyroid Transcription Factor-1 (TTF-1) is one of the most frequently used, and this study examined expressions of this panel in Rajavithi Hospital in order to assess their significance. Objective: To study the expression of CK7, CK20 and TTF-1 in metastatic carcinoma in neck node biopsy found in the Rajavithi Hospital database, and to assess their effectiveness in identifying pulmonary origin. Material and Method: The Rajavithi Hospital database was searched for all cases of lymph node biopsy in the neck and supraclavicular area for which the pathological diagnosis was metastatic carcinoma. Expressions of CK7, CK20 and TTF-1 were analyzed to measure their sensitivity, specificity, positive predictive values, and negative predictive values. Results: Average age of the subjects, of whom 56.9% were male, was 61.35±12.9 years. Lung (51.2%), breast (7.3%) and gastrointestinal tract (6.5%) were the three most common organ site origins, and the most common cell type was adenocarcinoma. Expressions are shown in terms of sensitivity (98.4%), specificity (95.0%), positive predictive value (95.4%), negative predictive value (98.3%) and others. The most reliable antibody for identification of pulmonary origin was TTF-1. Conclusion: The immunohistochemistry panel of CK7, CK20 and TTF-1 in the Rajavithi Hospital database is useful as a guide in locating the origin of clinically unknown primary cases of metastatic cervical lymph nodes.

Morphophenotypic changes in human multistep hepatocarcinogenesis with translational implications.

BACKGROUND & AIMS: Human hepatocarcinogenesis in cirrhosis is thought to be multistep and characterized by a spectrum of nodular lesions, ranging from low to high grade dysplastic nodules (LGDN and HGDN) to early and progressed hepatocellular carcinoma (eHCC and pHCC). The aim of this study was to investigate the morphophenotypical changes of this sequence and their potential translational significance. METHODS: We scored the vascular profile, ductular reaction/stromal invasion and overexpression of five biomarkers (GPC3, HSP70, GS, CHC, and EZH2), in a series of 100 resected nodules (13 LGDN, 16 HGDN, 42 eHCC and 29 small pHCC). RESULTS: The score separated the four groups of nodules as individual entities (p<0.01). In the sequence, biomarker's overexpression progressively increased with parallel decrease of ductular reaction; the vascular remodeling started very early (LGDN) but did not further develop in a proportion of HCC. eHCC was the most heterogeneous entity, with marginal overlap with HGDN and pHCC. Liver environment (fibrosis, etiology) did not impact on the phenotype of the different nodules. A subclass of eHCC (16/42) without evidence of stromal invasion was identified, suggesting a "preinvasive stage" (p<0.05). For diagnosis, the application of four and five biomarkers (rather than the usual three) improved the sensitivity of the assay for the detection of eHCC (76% and 93% vs. 52%); biomarkers in alternative combinations, and also increased the sensitivity of the assay (GS+CHC+EZH2: 76%; GS+CHC+EZH2+HSP70: 90%). CONCLUSIONS: This study supports the multistep nature of human hepatocarcinogenesis, and suggests that eHCC is more heterogeneous than previously thought. This provides further information of the potential translational significance into clinical practice.

p16ink4 and cytokeratin 7 immunostaining in predicting HSIL outcome for low-grade squamous intraepithelial lesions: a case series, literature review and commentary.

p16ink4 and cytokeratin 7 (CK7) have been proposed to identify low-grade squamous intraepithelial lesions (LSIL) at greater or lesser risk for an outcome of high-grade squamous intraepithelial lesion (HSIL). We correlated CK7 and p16ink4 staining in LSILs with outcome on follow-up and placed this information in the context of prior reports. Cervical LSIL biopsies with at least 1-year follow-up information were immunostained for CK7 and p16ink4. Follow-up outcomes included no SIL, LSIL (persistence) or HSIL (CIN2+). In all, 109 LSILs were studied and 18.3% stained positive for CK7. Ninety-one percent of CK7-negative LSILs regressed, 4.5% persisted, and 4.5% had an HSIL outcome, versus 60, 20, and 20% of CK7-positive LSILs, respectively (P=0.036). p16ink4 status did not significantly associate with outcome. Review of the literature revealed a highly variable rate of both positive p16ink4 immunoreactivity in LSIL and CIN2+ outcome for p16-positive LSIL but a consistently high negative predictive value (>90%) in the case of no/low p16 expression. Inter-observer reproducibility for the diagnosis of CIN2 in the literature ranged from poor to good, with unanimous agreement on the diagnosis of CIN2 occurring in less than 25% of cases. As with high-risk human papillomavirus testing, the most clinically useful result of p16ink4 staining is a negative test, implying no lesion or CIN1 and conferring a low risk of HSIL outcome. HSIL outcomes ('progression') are highly variable and are subject to wide differences in inter-observer interpretation for CIN2. This argues against the wisdom of relying on p16ink4 to both predict CIN2+ or upgrade CIN1 to CIN2. It also begs the question of whether CIN2 should be replaced by an alternate and less pejorative term (SIL of intermediate grade) for lesions that are not reproducibly classified as LSIL or HSIL, with an appropriate management scheme.

Clear Cell Papulosis: Report of a Case With Unique Clinical and Histologic Findings.

Clear cell papulosis is a rare, self-limited, benign disease of early childhood, characterized by white macules and flat papules over the milk line. Histopathologically, it is characterized by scattered clear cells throughout the basal and/or suprabasal epidermal layers, which-as clear cells of Toker of the nipple do-typically express cytokeratin 7. They also exhibit other markers expected for adenoid differentiation, such as low-molecular weight cytokeratins, carcinoembryonic antigen, epithelial membrane antigen, and mucin. The age of onset, distribution of lesions, histopathology, and its benign behavior nature help to exclude clinically similar conditions, either benign or malignant. The authors report a case of clear cell papulosis in a 7-year-old Brazilian girl in whom lesions were observed on the legs and histologically formed by solid and adenoid aggregates of clear cells, in a similar fashion than clear fetal cells of Toker.

Ex vivo construction of a novel model of bioengineered bladder mucosa: A preliminary study.

OBJECTIVE: To generate and to evaluate ex vivo a novel model of bioengineered human bladder mucosa based on fibrin-agarose biomaterials. METHODS: We first established primary cultures of stromal and epithelial cells from small biopsies of the human bladder using enzymatic digestion and selective cell culture media. Then, a bioengineered substitute of the bladder lamina propria was generated using cultured stromal cells and fibrin-agarose scaffolds, and the epithelial cells were then subcultured on top to generate a complete bladder mucosa substitute. Evaluation of this substitute was carried out by cell viability and histological analyses, immunohistochemistry for key epithelial markers and transmission electron microscopy. RESULTS: The results show a well-configured stroma substitute with a single-layer epithelium on top. This substitute was equivalent to the control bladder mucosa. After 7 days of ex vivo development, the epithelial layer expressed pancytokeratin, and cytokeratins CK7, CK8 and CK13, as well as filaggrin and ZO-2, with negative expression of CK4 and uroplakin III. A reduction of the expression of CK8, filaggrin and ZO-2 was found at day 14 of development. An immature basement membrane was detected at the transition between the epithelium and the lamina propria, with the presence of epithelial hemidesmosomes, interdigitations and immature desmosomes. CONCLUSIONS: The present results suggest that this model of bioengineered human bladder mucosa shared structural and functional similarities with the native bladder mucosa, although the epithelial cells were not fully differentiated ex vivo. We hypothesize that this bladder mucosa substitute could have potential clinical usefulness after in vivo implantation.

Aberrant keratin 7 and 20 expression in triple-negative carcinoma of the breast.

Early studies characterizing the keratin (K) profile of various epithelial tissues indicated that breast carcinoma is K7 positive and K20 negative, but not all breast carcinomas show this profile. Triple-negative carcinoma (TNC) has been characterized by negativity for estrogen receptor (ER), progesterone receptor (PgR), and Her2/neu protein. TNC is more likely to metastasize to the viscera and present as a metastatic poorly different carcinoma. In our study, on the basis of immunohistochemical staining of ER, PgR, and Her2/neu, 75 of the 290 patients with invasive breast carcinoma were judged to have TNC. K20 expression was detected in 6 of 75 patients with TNC, and non-TNC was negative in all 215 cases (P = .0003). K7 expression was also detected in 72 of 75 TNC cases. However, non-TNC was negative in 26 of 215 cases, which was significant (P = .0457). An aberrant profile of K was observed in the TNC group, indicating that caution is needed in determining the site of primary tumors using immunohistochemical algorithms. It should be kept in mind that patients with TNC show highly variable K profiles in practical diagnosis.

Keratin 7 expression in lymph node metastases but not in the primary tumour correlates with distant metastases and poor prognosis in colon carcinoma.

Colorectal carcinoma (CRC) is one of the leading causes of cancer-related deaths worldwide. Alterations in keratin expression, including keratin 7 (K7), are frequent findings in multiple cancers, and they constitute a prognostic factor. The aim of our study was to evaluate the prognostic significance of K7 in the primary tumour and lymph node metastases in two separate cohorts of patients: the first one with lymph node involvement (LN+, 129 cases) and the second one free of LN metastases (LN-, 85 cases). Keratin 7 expression in CRC was analysed on tissue microarrays with immunohistochemistry and evaluated using the h-score. In the LN+ group K7 positivity was identified in 7/129 (5.4%) of primary tumours (PT) and lymph node metastases (LNM); concordance between them was 94% ( 0.396). Keratin 7 was expressed in 8/85 cases (9.4%) in the LN- group. K7 expression in LNM of the LN+ cohort correlated with shorter overall survival (OS) (p = 0.047) and presence of distant metastases at diagnosis (p = 0.005). Expression of K7 in the primary tumour in both cohorts did not correlate with survival. We conclude that the status of K7 expression in metastatic lymph nodes from CRC is a poor prognostic factor.

Hepatic cell proliferation plays a pivotal role in the prognosis of alcoholic hepatitis.

BACKGROUND & AIMS: The role of liver progenitor cell (LPC) expansion, known as a marker of disease severity, as well as the impact of macrophage activation on liver regeneration remains unclear in humans. We aimed to characterize the LPC and macrophage compartments in alcoholic hepatitis (AH), as well as gene expression patterns to identify predictors of a good prognosis in this setting. METHODS: Immunohistochemical studies for macrophages, proliferative hepatocytes, total and proliferative LPC, as well as whole liver microarray gene expression were performed on baseline liver biopsies of 58 AH patients early after admission. Abstinent cirrhotic patients were used as controls. Patients were qualified as "improvers" or "non-improvers" based on the change in MELD score three months after baseline. RESULTS: Compared to controls, AH patients demonstrated a significant expansion of macrophages, invasion of LPC and a higher number of proliferating hepatocytes and LPC. In AH patients, total LPC expansion (total Keratin7(+) cells) was associated with liver disease severity. The group of improvers (n=34) was characterized at baseline by a higher number of proliferating hepatocytes, proliferative LPC (double Keratin7(+)Ki67(+) cells) and liver macrophages as compared to non-improvers (n=24), despite similar clinical and biological variables. Upregulated genes in improvers were associated with cell cycle mitosis together with a major expression of SPINK1. CONCLUSIONS: Higher liver macrophage expansion, increased proliferative hepatocyte but also LPC number, as well as an upregulation of cell proliferation-related genes are associated with a favourable outcome. These new findings open novel therapeutic targets in AH.