Nested Variant of Urothelial Carcinoma Is a Luminal Bladder Tumor With Distinct Coexpression of the Basal Marker Cytokeratin 5/6.

OBJECTIVES: The nested variant of urothelial carcinoma (NVUC) is a rare bladder tumor that may possess a luminal molecular phenotype. We sought to determine whether a small immunohistochemical (IHC) panel using common surrogates for molecular phenotypes would reliably classify a cohort of pure NVUC cases. METHODS: IHC staining with a panel composed of markers for basal subtypes (CK5/6, CK14) and luminal subtypes (FOXA1, GATA3) was performed on pure small NVUC cases (n = 23) and 5 large NVUC cases (n = 5). Scoring of IHC stains was performed semiquantitatively. Individual cases were analyzed using previously reported IHC-based surrogates for molecular subtype. RESULTS: The phenotype of NVUC was classified as luminal from 60.1% (FOXA1+/CK5/6-) to 100% (GATA3+/CK14-) of cases using composite phenotypes. No cases possessed a basal or squamous cell carcinoma-like phenotype. The majority of small NVUC cases (69.5%) showed subset CK5/6 expression distinctly localized to the basal layers of tumor cell nests. Intratumoral heterogeneity was also noted in CK5/6 (21.7% of small NVUC cases) but no other markers. CONCLUSIONS: NVUC appears to express markers of both basal and luminal bladder tumors. Definitive gene expression profiling may be valuable to further characterize this unique histologic variant.

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.

High frequency of p16 and SOX10 coexpression but not androgen receptor expression in triple-negative breast cancers.

Triple-negative breast cancers (TNBCs) represent approximately 12-17% of all breast cancers and have distinctively aggressive clinical courses. Because routine biomarkers for breast cancer do not apply for TNBCs, it is essential to find novel prognostic markers and potential targets for therapeutic agents. p16 and SOX10 are emerging biomarkers with relatively unexplored expressions in TNBCs. We present an analysis of the expression of p16 and SOX10 in combination with that of androgen receptor (AR) and cytokeratin (CK) 5/6 in TNBCs. In addition, we used tissue microarrays (TMAs) to compare frequencies of p16 and SOX10 between TNBCs and non-TNBCs. Fifty-six TNBC samples with clinical data were stained immunohistochemically with p16, SOX10, AR, and CK5/6. Fifty-four cases (96.4%) were invasive ductal carcinoma, not otherwise specified, and 46 cases (82.1%) were Nottingham histologic grade 3. The majority of TNBC cases were positive for p16 (n = 44; 78.6%) and SOX10 (n = 48; 85.7%). AR was positive in 15 cases (26.8%). CK5/6 was positive in 24 cases (42.9%), which were classified as basal-like breast cancer (BLBC) subtype. The frequencies of p16 and SOX10 expression in BLBC and non-BLBC subtypes did not reveal significant statistical difference in a separate analysis. Using archived TNBC and non-TNBC TMAs, we observed that 56% of TNBC cases were positive for p16 compared with 16% of non-TNBC cases (p-value <0.0001). SOX10 was positive in 80% of TNBC cases compared with 35% of non-TNBC cases (p-value <0.0001). A significant correlation was observed between p16 and SOX10 coexpression in TNBC cases (n = 56/80, p = 0.02) but not in non-TNBC cases (n = 23/348; p = 0.626). In conclusion, p16 and SOX10 are frequently expressed in TNBC, regardless of CK5/6 expression. Furthermore, p16 and SOX10 are often coexpressed in TNBCs compared with non-TNBCs.

Electrical stimulation promotes the proliferation of human keratinocytes, increases the production of keratin 5 and 14, and increases the phosphorylation of ERK1/2 and p38 MAP kinases.

Effective wound healing remains a significant clinical challenge in reducing patient morbidity and improving quality of life. Wound healing is a complex process involving the endogenous electrical field. The electrical field can contribute to wound healing by activating keratinocytes to promote reepithelialization. The objective of this study was to determine the effects of exogenous electrical stimulation (ES) on human keratinocyte viability and proliferation and on production of IL-6, IL-8, and keratins (K5 and K14) and to investigate the activated signalling pathways in keratinocytes exposed to ES. Keratinocytes were cultured under ES at different intensities for 6 or 24 hr. Cell proliferation, cytokines and growth factors, K5 and K14, as well as phosphorylated ERK1/2 and p38 MAP kinases, were evaluated. The results showed that the keratinocytes exposed to ES between 100 and 150 mV/mm for 6 or 24 hr showed a significantly increased proliferation rate. However, a 24 hr exposure to 200 mV/mm revealed no significant effect in cell growth. ES at 100 and 200 mV/mm for 6 hr increased the secretion of epidermal growth factor and vascular endothelial growth factor, and the production of K5 and K14. K14 was more sensitive than K5 to ES. However, ES down-regulated the secretions of IL-6 and IL-8. Finally, ES increased the phosphorylation of ERK1/2 and p38 MAP kinases. Overall results suggested that ES can be useful in supporting skin wound healing by activating keratinocytes.

The coexpression of fibroblast activation protein (FAP) and basal-type markers (CK 5/6 and CD44) predicts prognosis in high-grade invasive urothelial carcinoma of the bladder.

High-grade urothelial carcinoma (UC) of the bladder is a heterogeneous disease with dismal prognosis. Bladder tumors with basal phenotype are intrinsically aggressive, and morphological parameters that define disease staging remain main prognosticators. We intend to evaluate the role of cancer-associated fibroblasts (CAFs) in the prognosis of bladder cancer and its association with basal and luminal phenotypes. Clinical and pathological parameters, including the immunohistochemical expression of fibroblast activation protein (FAP) and markers of basal (CK5/6, CD44) and luminal (CK20, GATA3) phenotypes, have been investigated in a series of 121 patients with UC of the bladder treated by radical cystectomy with lymph node dissection, and their implication in long-term cancer-specific survival has been evaluated. A cytoplasmic immunostaining of FAP in CAFs implies worse disease-specific survival (hazard ratio [HR] = 1.68; P = .048). FAP expression is associated with tumor staging (P < .0001), with best discrimination at T2a/T2b level, and with negative expression of markers of luminal phenotype, such as CK20 (P < .0001) and GATA3 (P = .005). In the multivariate analysis, simultaneous expression of FAP, CK5/6, and CD44 is a strong prognosticator of disease-specific survival (HR = 2.3; P = .001), together with nodal invasion (HR = 3.47; P < .0001) and bladder infiltration up to deep muscle or beyond (HR = 2.47; P = .02). There is no association between positive FAP expression in primary tumor and nodal disease (P = .22). FAP expression in CAFs favors tumor invasion in high-grade invasive UC of the bladder with basal phenotype. This new immunohistochemical marker could be added to the routine immunohistochemical protocol to predict clinical behavior in these patients.

Predicting outcomes in non-muscle invasive (Ta/T1) bladder cancer: the role of molecular grade based on luminal/basal phenotype.

Bladder cancer tumors can be divided into two molecular subtypes referred to as luminal or basal. Each subtype may react differently to current chemotherapy or immunotherapy. Likewise, the technology required for comprehensive molecular analysis is expensive and not yet applicable for routine clinical diagnostics. Therefore, it has been suggested that the immunohistochemical expressions of only two markers, luminal (CK20+, CK5/6-) and basal (CK5/6+, CK20-), is sufficient to identify the molecular subtypes of bladder cancer. This would represent a molecular grade that could be used in daily practice. Molecular classification is done using immunohistochemistry to assess luminal-basal phenotype based on tissular expression of CK20 and CK5/6 as surrogate for luminal or basal subtypes, respectively. A series of 147 non-muscle-invasive bladder carcinoma cases was selected, and the tumors were divided into four subgroups based on the presence of CK20 and/or CK5/6, that is, null (CK20-, CK5/6-), mixed (CK20+, CK5/6+), basal (CK20-, CK5/6+), and luminal (CK20+, CK5/6-) categories. Survival analysis was estimated using the Kaplan-Meier method and the log-rank test. Hazard ratios were calculated by Cox multivariate analysis. The molecular grade included cases with null (n = 89), mixed (n = 6), basal (n = 20), and luminal (n = 32) phenotypes with differences in recurrence-free, progression-free and cancer-specific survival associated with molecular-grade categories in patients with low- or high-grade Ta, or high-grade T1 tumors. The multivariate analysis identified the luminal phenotype as a predictor of more aggressive neoplasms. Our findings provide a rationale to investigate luminal and basal subtypes of bladder cancer using two gene expression signatures as surrogate markers and show that non-muscle-invasive bladder carcinoma can be stratified into biologically and clinically different subgroups by using an immunohistochemical classifier.

Expression of PTEN, Androgen Receptor, HER2/neu, Cytokeratin 5/6, Estrogen Receptor-Beta, HMGA2, and PLAG1 in Salivary Duct Carcinoma.

Salivary duct carcinoma (SDC) is an aggressive neoplasm that resembles high-grade invasive ductal carcinoma of the breast. It can develop de novo or from the malignant transformation of pleomorphic adenoma (PA). We performed immunohistochemical stains for phosphatase and tensin homologue [PTEN androgen receptor (AR)], HER2/neu, cytokeratin 5/6, estrogen receptor-beta, high-mobility group AT-hook 2 (HMGA2), and pleomorphic adenoma gene 1 (PLAG1) on tissue microarray samples of 75 SDCs and 31 adenocarcinomas, not otherwise specified (NOS). Our data showed the following in SDC samples: loss of PTEN was found in 17 of 60 (28.3%); AR was expressed in 43 of 62 (69.4%); HER2/neu was overexpressed in 25 of 58 (43.1%); cytokeratin 5/6 was expressed in 14 of 54 (25.9%); estrogen receptor-beta was expressed in 37 of 56 (66.1%); HMGA2 was expressed in 29 of 63 (46.0%); and PLAG1 was expressed in 0 of 62 (0%). In addition, there was no statistically significant difference in the age at onset between patients with HMGA2-positive SDCs (range 32-85 years; mean: 64.3 years; median: 64.5 years) and those with HMGA2-negative SDCs (range 41-79 years; mean: 62.5 years; median: 64.5 years). There was also no statistically significant difference in overall survival between patients with HMGA2-positive and HMGA2-negative SDCs (follow-up period range 3-201 months; mean: 49.8 months; median: 30 months). Among 10 patients with a definite PA component (SDC ex-PA), 6 were positive and 4 were negative for HMGA2. Our data were consistent with previous findings that AR and estrogen receptor-beta are expressed in most SDCs, whereas HER2/neu overexpression and loss of PTEN are expressed in a subset of SDCs. In our cohort of patients, HMGA2 was expressed in approximately half of SDCs. HMGA2 and PTEN are promising therapeutic targets for salivary gland tumors.

Immunohistochemistry of cytokeratin (CK) 5/6, CD44 and CK20 as prognostic biomarkers of non-muscle-invasive papillary upper tract urothelial carcinoma.

AIMS: Immunohistochemical (IHC) staining for cytokeratin (CK) 5/6, CD44 and CK20 has been significantly associated with the prognosis of urinary bladder urothelial carcinoma, and probably reflects its molecular characteristics. We aimed to investigate the IHC-based subgroups and their prognostic effects on non-muscle-invasive papillary upper tract urothelial carcinoma (UTUC). METHODS AND RESULTS: IHC staining for CK5/6, CK20 and CD44 was analysed in 211 patients with non-muscle-invasive papillary UTUC. Staining was classified as showing a negative, positive or normal pattern. We found that CK5/6-negative, CD44-negative and CK20-positive tumours were distinctly high-risk subgroups that were associated with high grade (CK5/6-negative, P < 0.001; CD44-negative, P < 0.001; CK20-positive, P = 0.017) and frequent intravesical recurrence (CK5/6-negative, P = 0.002). Using survival analysis with Kaplan-Meier and log-rank tests, we found that these IHC subgroups were correlated with poor progression-free (CK5/6-negative, P = 0.001; CD44-negative, P = 0.009; CK20-positive, P = 0.031) and cancer-specific (CK5/6-negative, P = 0.009) survival. Furthermore, CK5/6 negativity was an independent prognostic factor for shorter progression-free (P = 0.009) and cancer-specific (P = 0.045) survival. CK5/6 improved Harrell's C-indices for progression-free (0.68-0.77, P = 0.029) and cancer-specific (0.59-0.77, P < 0.001) survival. When markers were combined, luminal-like subtypes showed poor prognoses. CONCLUSIONS: We demonstrated that IHC staining for CK5/6, CD44 and CK20 was significantly associated with the clinicopathological characteristics and prognoses of patients with non-muscle-invasive papillary UTUC. The IHC subgroups may be correlated with the molecular characteristics of non-muscle-invasive papillary UTUC.

Identification of a subtype of poorly differentiated invasive ductal carcinoma of the breast based on vimentin and e-cadherin expression / Identificação de um subtipo pouco diferenciado de carcinoma ductal invasivo de mama, baseado na expressão da vimentina e E-caderina

Abstract Objective The use of molecular markers can identify a subgroup of tumors with distinct recurrence patterns. The present study aimed to characterize the immunohistochemical expression of vimentin (VIM), of E-cadherin (CDH1), and of cytokeratin 5 (CK5) in patients with invasive ductal carcinomas (IDCs). Methods We have constructed a tissuemicroarray (TMA) from87 patients with IDC of the breast. Immunohistochemistry (IHC) was performed to study the expression of estrogen and progesterone receptors (ER and PgR), human epidermal growth factor receptor 2 (HER2), VIM, CDH1, CK5, and Ki67. The tumors were classified as luminal A and B (n = 39), HER2 enriched (n = 25), and triple-negative (TNBC) (n = 23), based on the IHC expression. Results We have observed that luminal A and B tumors lack the VIM+/CDH1-/low phenotype. This phenotype was observed in 16.5% of the HER2+ tumors and in 60% of the TNBC tumors (p = 0.0001). Out of a total of 20 TNBC tumors, the CK5 (basal-like marker) was positive in 11 of them. The VIM+/CDH1-/low phenotype was observed in 5 CK5+ TNBC tumors (45%) and in 7 out of 9 CK5- TNBC tumors (78%) (p = 0.02). The median Ki67 index in the VIM+/CDH1-/low tumors was 13.6 (range: 17.8-45.4) compared with 9.8 (range: 4.1-38.1) in other tumors (p = 0.0007). The presence of lymph nodemetastasis was less frequent in patients with VIM+/CDH1-/low tumors (23% versus 61%; X2 test; p = 0.01). Conclusion Our findings suggest that the expression of VIM and CDH1 can identify a subset of IDCs of the breast with a mesenchymal phenotype associated with poor prognosis, high-grade lesion, and high mitotic index.

Resumo Objetivo O uso de marcadores moleculares pode identificar subtipos tumorais com diferentes taxas de recidiva. O objetivo do presente estudo é caracterizar a expressão imunohistoquímica da vimentina (VIM), da E-caderina (CDH1) e de CK5 em pacientes com carcinoma ductal invasivo (CDI) da mama. Métodos Utilizamos uma matriz de amostras teciduais (TMA, na sigla em inglês) de 87 pacientes com CDI da mama. Para avaliar a expressão dos receptores de estrogênio (RE) e receptores de progesterona (RP), HER2, VIM, CDH1, CK5 e Ki67, utilizamos imunohistoquímica. Os tumores foram classificados como luminal A e B (n = 39), HER2+ (n = 25) e triplo negativo (TNBC) (n = 23). Resultados Foi observado que tumores luminais A e B não expressaram o fenótipo VIM+/CDH1-/low. Este fenótipo foi observado em 16,5% dos tumores HER2+ e em 60% dos tumores TNBC (p = 0,0001). Dos 20 tumores TNBC, a CK5 (marcador de tumor basalóide) foi super expressa em 11 amostras. O fenótipo VIM+/CDH1-/low foi observado em 5 tumores CK5+ TNBC (45%) e em 7 dos 9 tumores CK5- TNBC (78%) (p = 0,02). A expressão média de Ki67 nos tumores VIM+/CDH1-/low foi 13.6 (amplitude de 17,8 a 45,4) comparado com 9,8 (amplitude de 4,1 a 38,1) nos outros tumores (p = 0,0007). A presença demetástase linfonodal foimenor em tumores com fenótipo VIM+/CDH1-/low (23% contra 61%; teste X2; p = 0,01). Conclusão Nossos achados sugerem que a expressão de VIM e CDH1 pode identificar um subtipo de CDI da mama com fenótipo mesenquimal associado a pior prognóstico, lesões de alto grau e alto índice mitótico.

mRNA-Expression of KRT5 and KRT20 Defines Distinct Prognostic Subgroups of Muscle-Invasive Urothelial Bladder Cancer Correlating with Histological Variants.

Recently, muscle-invasive bladder cancer (MIBC) has been subclassified by gene expression profiling, with a substantial impact on therapy response and patient outcome. We tested whether these complex molecular subtypes of MIBC can be determined by mRNA detection of keratin 5 (KRT5) and keratin 20 (KRT20). Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) was applied to quantify gene expression of KRT5 and KRT20 using TaqMan®-based assays in 122 curatively treated MIBC patients (median age 68.0 years). Furthermore, in silico analysis of the MD Anderson Cancer Center (MDACC) cohort (GSE48277 + GSE47993) was performed. High expression of KRT5 and low expression of KRT20 were associated with significantly improved recurrence-free survival (RFS) and disease-specific survival disease specific survival (DSS: 5-year DSS for KRT5 high: 58%; 5-year DSS for KRT20 high: 29%). KRT5 and KRT20 were associated with rates of lymphovascular invasion and lymphonodal metastasis. The combination of KRT5 and KRT20 allowed identification of patients with a very poor prognosis (KRT20⁺/KRT5-, 5-year DSS 0%, p < 0.0001). In silico analysis of the independent MDACC cohorts revealed congruent results (5-year DSS for KRT20 low vs. high: 84% vs. 40%, p = 0.042). High KRT20-expressing tumors as well as KRT20⁺/KRT- tumors were significantly enriched with aggressive urothelial carcinoma variants (micropapillary, plasmacytoid, nested).

Identification of a Subtype of Poorly Differentiated Invasive Ductal Carcinoma of the Breast Based on Vimentin and E-cadherin Expression.

OBJECTIVE: The use of molecular markers can identify a subgroup of tumors with distinct recurrence patterns. The present study aimed to characterize the immunohistochemical expression of vimentin (VIM), of E-cadherin (CDH1), and of cytokeratin 5 (CK5) in patients with invasive ductal carcinomas (IDCs). METHODS: We have constructed a tissue microarray (TMA) from 87 patients with IDC of the breast. Immunohistochemistry (IHC) was performed to study the expression of estrogen and progesterone receptors (ER and PgR), human epidermal growth factor receptor 2 (HER2), VIM, CDH1, CK5, and Ki67. The tumors were classified as luminal A and B (n = 39), HER2 enriched (n = 25), and triple-negative (TNBC) (n = 23), based on the IHC expression. RESULTS: We have observed that luminal A and B tumors lack the VIM+/CDH1-/low phenotype. This phenotype was observed in 16.5% of the HER2+ tumors and in 60% of the TNBC tumors (p = 0.0001). Out of a total of 20 TNBC tumors, the CK5 (basal-like marker) was positive in 11 of them. The VIM+/CDH1-/low phenotype was observed in 5 CK5+ TNBC tumors (45%) and in 7 out of 9 CK5- TNBC tumors (78%) (p = 0.02). The median Ki67 index in the VIM+/CDH1-/low tumors was 13.6 (range: 17.8-45.4) compared with 9.8 (range: 4.1-38.1) in other tumors (p = 0.0007). The presence of lymph node metastasis was less frequent in patients with VIM+/CDH1-/low tumors (23% versus 61%; X2 test; p = 0.01). CONCLUSION: Our findings suggest that the expression of VIM and CDH1 can identify a subset of IDCs of the breast with a mesenchymal phenotype associated with poor prognosis, high-grade lesion, and high mitotic index.

OBJETIVO: O uso de marcadores moleculares pode identificar subtipos tumorais com diferentes taxas de recidiva. O objetivo do presente estudo é caracterizar a expressão imunohistoquímica da vimentina (VIM), da E-caderina (CDH1) e de CK5 em pacientes com carcinoma ductal invasivo (CDI) da mama. MéTODOS: Utilizamos uma matriz de amostras teciduais (TMA, na sigla em inglês) de 87 pacientes com CDI da mama. Para avaliar a expressão dos receptores de estrogênio (RE) e receptores de progesterona (RP), HER2, VIM, CDH1, CK5 e Ki67, utilizamos imunohistoquímica. Os tumores foram classificados como luminal A e B (n = 39), HER2+ (n = 25) e triplo negativo (TNBC) (n = 23). RESULTADOS: Foi observado que tumores luminais A e B não expressaram o fenótipo VIM+/CDH1-/low. Este fenótipo foi observado em 16,5% dos tumores HER2+ e em 60% dos tumores TNBC (p = 0,0001). Dos 20 tumores TNBC, a CK5 (marcador de tumor basalóide) foi super expressa em 11 amostras. O fenótipo VIM+/CDH1-/low foi observado em 5 tumores CK5+ TNBC (45%) e em 7 dos 9 tumores CK5- TNBC (78%) (p = 0,02). A expressão média de Ki67 nos tumores VIM+/CDH1-/low foi 13.6 (amplitude de 17,8 a 45,4) comparado com 9,8 (amplitude de 4,1 a 38,1) nos outros tumores (p = 0,0007). A presença de metástase linfonodal foi menor em tumores com fenótipo VIM+/CDH1-/low (23% contra 61%; teste X2 ; p = 0,01). CONCLUSãO: Nossos achados sugerem que a expressão de VIM e CDH1 pode identificar um subtipo de CDI da mama com fenótipo mesenquimal associado a pior prognóstico, lesões de alto grau e alto índice mitótico.

Cytokeratin 5/6 expression in bladder cancer: association with clinicopathologic parameters and prognosis.

OBJECTIVES: Well differentiated keratinized squamous component as a part of urothelial carcinoma can be easily appreciated; however non-keratinizing squamous differentiation closely resembles urothelial differentiation. In addition prognostic significance of CK 5/6 expression in the absence of apparent squamous differentiation is still unclear. Therefore, in the present study we aimed to evaluate the frequency of CK 5/6 expression in 127 cases of urothelial carcinoma and its prognostic significance in loco-regional population. RESULTS: Positive CK5/6 expression was noted in 6.3% (8 cases) and 13.4% (17 cases) revealed focal positive CK 5/6 expression. On the other hand, 80.3% (102 cases) showed negative CK5/6 staining. Significant association of CK5/6 expression was noted with tumor grade and muscularis propria invasion, however no significant association was noted with overall and disease free survival. On the basis of the results of our study we can conclude that CK5/6 is an independent prognostic biomarker in urothelial carcinoma and therefore can be used in the prognostic stratification of the patients with bladder cancer.

Immunohistochemical Analysis of the Expression of Breast Markers in Basal-like Breast Carcinomas Defined as Triple Negative Cancers Expressing Keratin 5.

Estrogen and progesterone receptors are possible markers for suggesting a mammary origin of metastatic carcinoma, but are useless in cases of triple negative breast cancers (TNBC). Five other potential markers of breast origin were investigated on tissue microarrays in a series of TNBCs showing keratin 5 expression, consistent with a basal-like phenotype. GATA-3 staining was observed in 82 of 115 triple negative cases (71.3%) including 23 cases with >5% staining. Mammaglobin staining was detected in 30 cases (26.0%) including 12 with >5% staining. GCDFP-15 was seen in 23 cases (20.0%) including 9 with >5% staining. NY-BR-1 positivity was present in 7 cases (6.0%) including 3 patients with >5% staining. BCA-225 staining was observed in 74 cases (64.3%); however this latter marker lacks also specificity owing to the reported widespread staining in other malignancies. GATA-3, mammaglobin and GCDFP-15 coexpression was seen in one case (0.9%), whereas GATA-3 and mammaglobin or mammaglobin and GCDFP-15 coexpression was present in 2 and 2 cases (1.7%), respectively. Using at least 5% staining as cut-off, the expression of any of the last 4 markers was 34.7%. The expression of GATA-3, mammaglobin, GCDFP-15 and NY-BR-1 is lower in TNBC-s than in breast carcinomas in general, and this may be even lower in basal-like carcinomas. Although these markers are not fully specific, by using them, a subset of basal-like TNBC-s can be identified as of mammary origin. However, a substantial proportion will not show any staining with any of these markers.

Basal cell carcinoma: CD56 and cytokeratin 5/6 staining patterns in the differential diagnosis with Merkel cell carcinoma.

BACKGROUND: Basal cell carcinoma (BCC) can resemble Merkel cell carcinoma (MCC) on histopathological examination and while CK20 is a useful marker in this differential, it is occasionally negative in MCC. CD56, a sensitive marker of neuroendocrine differentiation, is sometimes used to identify MCC, but has been reportedly variably positive in BCC as well. In contrast, CK5/6 consistently labels BCC but is not expressed in neuroendocrine tumors. METHODS: We evaluated 20 cases of BCC for the pattern of CD56 and cytokeratin 5/6 (CK5/6) staining, hypothesizing that these 2 stains could differentiate BCC from MCC in difficult cases. Seventeen cases of MCC previously stained with CD56 were also examined. RESULTS: All BCCs showed patchy expression of CD56 except for 2 cases, which showed staining of greater than 70% of tumor. CK5/6 was diffusely positive in all cases of BCC. Fifteen of 17 MCCs were diffusely positive for CD56. The difference in the pattern of CD56 expression between MCC and BCC (diffuse vs patchy, respectively) was statistically significant (P < .05). CONCLUSION: BCC typically shows patchy CD56 expression and diffuse CK5/6 positivity. These 2 markers can be used to distinguish between BCC and MCC in challenging cases.

In stage pT1 non-muscle-invasive bladder cancer (NMIBC), high KRT20 and low KRT5 mRNA expression identify the luminal subtype and predict recurrence and survival.

Differential expression of cytokeratins (CK) is a characteristic feature of chemoresistant luminal (KRT20) and chemosensitive intrinsic aggressive basal (KRT5) subtypes in muscle-invasive bladder cancer (MIBC). We investigated mRNA expression of KRT5 and KRT20 and its predictive value in stage pT1 bladder cancer. In retrospective analysis of clinical data and formalin-fixed paraffin-embedded tissues (FFPE) of patients with stage pT1 NMIBC who underwent transurethral resection of the bladder, a single-step RT-qPCR was used to measure mRNA expression. Furthermore, immunohistochemical (IHC) staining of CK20, panCK, and MIB1 was performed. Valid measurements were obtained from 231 samples out of a series of 284 patients. Spearman correlation revealed significant associations between mRNA and protein expression of KRT20/CK20 (ρ 0.6096, p < 0.0001) and MKI67/MIB1 (ρ 0.5467, p < 0.0001). A positive correlation was found between MKI67 and KRT20 expression (ρ 0.3492, p < 0.0001), while MKI67 and KRT5 were negatively correlated (ρ -0.1693, p = 0.01). High KRT20 expression (≥40.26) was significantly associated with worse recurrence free survival (RFS) (p = 0.001), progression-free survival (PFS) (p = 0.0003), and cancer specific survival (CSS) (p = 0.0414). The combination of high KRT20 expression and low KRT5 expression (<36.83) was associated with unfavorable RFS (p = 0.0038) and PFS (p = 0.0003) and proved to be the only independent predictor for RFS (p = 0.0055) and PFS (p = 0.0023) in multivariate analysis. KRT20 mRNA determination was superior to CK20 protein estimation with regard to RFS and PFS prediction. KRT20 and KRT5 mRNA quantification can predict recurrence and progression of stage pT1 NMIBC reflecting basal and luminal subtypes of MIBC and is superior to CK20 protein expression determined by IHC.

The expression patterns of aquaporin 9, vacuolar H+-ATPase, and cytokeratin 5 in the epididymis of the common vampire bat.

Desmodus rotundus is a vampire bat species that inhabits Latin America. Some basic aspects of this species' biology are still unknown, as the histophysiological characteristics of the male reproductive tract. Our study has focused on its epididymis, which is an important organ for performing a variety of functions, especially the sperm maturation and storage. The aim of this study was to identify principal, narrow, clear, and basal cells using cell-specific markers such as aquaporin 9 (AQP9), vacuolar H+-ATPase (V-ATPase), and cytokeratin 5 (KRT5). Principal cells were labeled by AQP9 from initial segment to cauda region in their stereocilia. They were shown with a columnar shape, whereas V-ATPase-rich cells were identified with a goblet-shaped body along the entire epididymis, including the initial segment, which were named as clear cells. Pencil-shaped V-ATPase-rich cells (narrow cells) were not detected in the initial segment of the bat epididymis, unlike in the rodent. Basal cells were labeled by KRT5 and were located at the basal portion of the epithelium forming a dense network. However, no basal cells with a luminal-reaching body extension were observed in the bat epididymis. In summary, epithelial cells were identified by their specific markers in the vampire bat epididymis. Principal and basal cells were labeled by AQP9 and KRT5, respectively. Narrow cells were not observed in the vampire bat epididymis, whereas clear cells were identified by V-ATPase labeling along the entire duct in a goblet-shaped body. In addition, no luminal-reaching basal cells were observed in the vampire bat epididymis.

Hyperglycemia Induces Skin Barrier Dysfunctions with Impairment of Epidermal Integrity in Non-Wounded Skin of Type 1 Diabetic Mice.

Diabetes causes skin complications, including xerosis and foot ulcers. Ulcers complicated by infections exacerbate skin conditions, and in severe cases, limb/toe amputations are required to prevent the development of sepsis. Here, we hypothesize that hyperglycemia induces skin barrier dysfunction with alterations of epidermal integrity. The effects of hyperglycemia on the epidermis were examined in streptozotocin-induced diabetic mice with/without insulin therapy. The results showed that dye leakages were prominent, and transepidermal water loss after tape stripping was exacerbated in diabetic mice. These data indicate that hyperglycemia impaired skin barrier functions. Additionally, the distribution of the protein associated with the tight junction structure, tight junction protein-1 (ZO-1), was characterized by diffuse and significantly wider expression in the diabetic mice compared to that in the control mice. In turn, epidermal cell number was significantly reduced and basal cells were irregularly aligned with ultrastructural alterations in diabetic mice. In contrast, the number of corneocytes, namely, denucleated and terminally differentiated keratinocytes significantly increased, while their sensitivity to mechanical stress was enhanced in the diabetic mice. We found that cell proliferation was significantly decreased, while apoptotic cells were comparable in the skin of diabetic mice, compared to those in the control mice. In the epidermis, Keratin 5 and keratin 14 expressions were reduced, while keratin 10 and loricrin were ectopically induced in diabetic mice. These data suggest that hyperglycemia altered keratinocyte proliferation/differentiation. Finally, these phenotypes observed in diabetic mice were mitigated by insulin treatment. Reduction in basal cell number and perturbation of the proliferation/differentiation process could be the underlying mechanisms for impaired skin barrier functions in diabetic mice.

Clinical significance of CD44 variant 9 expression as a prognostic indicator in bladder cancer.

CD44, a major surface receptor for hyaluronic acid, has multiple isoforms and represents a major cancer stem cell marker for various epithelial tumors. CD44 variant 9 (CD44v9) was correlated with recurrence and metastasis in gastric and colon cancer. We examined its role in invasion and as a biomarker for the basal muscle invasive molecular subtype showing worse prognosis, and for tumor progression in high risk (pT1/high grade) non­muscle invasive bladder cancers (NMIBCs). CD44v9, cytokeratin 5/6 (CK5/6), and cytokeratin 20 (CK20) expression was evaluated by immunohistochemistry in 98 pathologically confirmed specimens (36 muscle and 62 high­risk non­muscle) and correlated to clinical outcome. In vitro analysis was performed using two human bladder cancer cell lines (HT1376 and 5637). The CD44v9 high­expressing group exhibited significantly lower progression­free and cancer­specific survival rates in both muscle (P=0.0349 and 0.0382, respectively) and non­muscle (P=0.0002 and 0.0079) invasive patients. CD44v9 expression was significantly correlated with CK5/6 (P<0.001), colocalizing at the muscle invasion front but distinctly separated from CK20 in non­muscle invasion. CD44 and CD44v9 siRNA knockdown demonstrated significantly lower Matrigel invasion ability and significantly shorter migration distance (all P<0.01). CD44 and CD44v9 knockdown increased E­cadherin and decreased N­cadherin, snail, and slug epithelial­mesenchymal transition marker protein expression. Thus, higher CD44v9 expression was associated with worse prognosis, likely impacting invasion and migration via the epithelial­mesenchymal transition. Together, these findings suggest that CD44v9 expression might be a useful predictive biomarker in basal­type muscle and high-risk NMIBC.

[Metaplastic carcinoma of the breast and the impact of the p63 and cytokeratin 5/6: experience of 40 patients]. / Carcinoma metaplásico de mama y repercusión de la expresión de p63 y citoqueratina 5/6: experiencia de 40 pacientes.

BACKGROUND: Metaplasic carcinoma of the breast was initially described by Huvos in 1974. It is a rare and aggressive entity characterized by the presence of mesenchymal and epithelial components. OBJECTIVE: To know the incidence and biologic behaviour of the metaplasic carcinoma of the breast at the Instituto de Enfermedades de la Mama, FUCAM, AC. METHODS: Data on women diagnosed with metaplasic carcinoma of the breast between January 2005 and December 2014 was collected by retrospectively reviewing in FUCAM. Clinical, pathological and immunohistochemical characteristics were assessed. The five-year disease-free survival (DFS) and overall survival (OS) were evaluated. RESULTS: a total of 4198 patients have been diagnosed with breast cancer in our institution, 40 (0.95%) of them with metaplasic carcinoma. The median age of the patients was 46 years (27-73). 60% of the patients were diagnosed with an advanced clinical stage (III) and the triple-negative subtype was the most frequently found. A mean follow-up of 24 months showed rates of overall survival and disease-free survival of 80% and 69.9%, respectively. The presence of both, cytokeratins 5/6 and p63, seems to have a negative impact in local recurrence. CONCLUSION: this study demonstrates that metaplasic carcinoma is a rare and aggressive disease. Expression of both tumor cytokeratins was associated with a worse outcome.