Engrailed Homeobox 1 and Cytokeratin 19 Are Independent Diagnostic Markers of Eccrine Porocarcinoma and Distinguish It From Squamous Cell Carcinoma.

OBJECTIVES: The diagnostic utility of En1 in the histopathologic differentiation of eccrine porocarcinoma (EPC) from invasive squamous cell carcinoma (SCC) was investigated. METHODS: Expression of En1 and CK19 in 16 cases of EPC was immunohistochemically examined and compared with that in 32 cases of SCC. RESULTS: In all 16 EPCs, En1 was expressed in 3% to 100% of tumor cells. In 20 of the 32 SCCs, En1 was expressed in 3% to 90% of tumor cells. A total of 13 of the 16 EPCs and five of the 32 SCCs were judged as En1 positive, with a cutoff value of 25%. In addition, 11 of the 16 EPCs and four of the 32 SCCs were CK19 positive. The frequencies of En1- and CK19-positive cases were significantly higher in EPCs than in SCCs. In a logistic regression analysis for predicting EPC, En1 and CK19 were independent markers. When expression patterns of En1 and CK19 were combined, none of the 32 SCCs was both positive. In contrast, 15 of the 16 EPCs were positive for either En1 or CK19. CONCLUSIONS: A combination of En1 and CK19 expression can improve the accuracy of histologic diagnosis of EPC.

Keratin 19-expressing hepatocellular carcinoma and small-duct type intrahepatic cholangiocarcinoma show a similar postoperative clinical course but have distinct genetic features.

AIMS: The present study aimed to systematically compare clinicopathological and genetic features between keratin 19 (K19)-expressing hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). METHODS AND RESULTS: Consecutive cases of HCC (n = 430) were classified into K19+ and K19- using immunohistochemistry. ICCA cases were also separated into small-(S-iCCA; n = 36) and large-duct types (n = 22) based on recently proposed criteria, with the former being used in the present study. Mutational hot-spots in TERT, CTNNB1, KRAS and IDH1 were sequenced. Twenty-six cases (6%) of HCC expressed K19. K19+ HCC was more strongly associated with chronic hepatitis B than K19- HCC and S-iCCA (46% versus 17% and 6%; both P < 0.001). Lymph node metastasis was observed in K19+ HCC (8%) and S-iCCA (22%), but was exceptional in K19- HCC (1%). K19+ HCC had TERT promoter mutations less frequently than K19- HCC (31% versus 59%; P = 0.022), and lacked alterations in KRAS and IDH1. CTNNB1 mutations were similarly observed in K19+ and K19- HCC (23% and 19%, respectively), but rare in S-iCCA (3%). The postoperative survival curve of K19+ HCC was almost identical to that of S-iCCA in the first 5 years (approximately 50% at 5 years), and significantly worse than that of K19- HCC (P = 0.040). Extrahepatic recurrence was more common in K19+ HCC (50%) and S-iCCA (35%) than in K19- HCC (15%) (P = 0.001). CONCLUSIONS: Although K19+ HCC and S-iCCA showed similar biological behaviours, they did not share any driver gene mutations, suggesting the possible involvement of epigenetic alterations in the iCCA-like features of K19+ HCC.

Diagnostic value of HBME-1, CK19, Galectin 3, and CD56 in the subtypes of follicular variant of papillary thyroid carcinoma.

Our aim is to explore differences in Hector Battifora mesothelial-1 (HBME-1), cytokeratin-19 (CK19), Galectin-3 (Gal-3), and CD56 expression in infiltrative follicular variants of papillary carcinoma (IFVPTC) and encapsulated follicular variants of papillary carcinoma (EFVPTC) and to provide clues for distinguishing the two subtypes preoperatively. Tissue microarrays from 100 EFVPTC (45 non-invasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP) and 55 invasive EFVPTCs), 43 IFVPTCs, and 64 follicular neoplasms (FN) were immunostained with HBME-1, CK19, Gal-3, and CD56. Each case was scored 1 point for every positive result. Immunohistochemical expression was not significantly different in invasive EFVPTC and NIFTP, except for that of HBME-1. HBME-1, CK19, Gal-3, and CD56 expression were significantly higher in IFVPTC than in EFVPTC. At the cutoff of 3 points, the score method had special diagnostic value for differentiating IFVPTC from EFVPTC and FN and for predicting lymph node metastasis. Scoring of immunohistochemistry results may be applied to core biopsy or cell blocks to assist ultrasonographic, cytologic and molecular tests in differentiating IFVPTC and EFVPTC preoperatively, possibly appropriately guiding EFVPTC preoperatively for limited operation or active surveillance.

CD34, PCNA and CK19 expressions in AFP- hepatocellular carcinoma.

OBJECTIVE: Primary hepatocellular carcinoma (HCC) is one of the most important malignant liver cancers in clinic. Serum alpha-fetoprotein (AFP) positive expression is an important examination index. However, there are some hepatocellular carcinoma patients show negative AFP expressions. Therefore, how to screen AFP- hepatocellular carcinoma patients is important and difficult. PATIENTS AND METHODS: Total of 80 cases of AFP- hepatocellular carcinoma patients with or without focal nodular hyperplasia (FNH) confirmed by surgery was enrolled. Clinical information was collected for correlation analysis. Real-time PCR (RT-PCR) and Western blot were applied for gene expression analysis, and the target gene includes CD34, proliferation cell nuclear antigen (PCNA) and cell keratin 19 (CK19). Their relationship was analyzed. RESULTS: CD34 positive rate in the 80 cases was 48%, of which patients with FNH showed higher expression level than those of patients without FNH. The PCNA positive rate was 38%, and there was no statistical difference between patients with and without FNH. The CK19 positive rate was 56%, while the patients with FNH presented a higher level than the patients without FNH. CD34, PCNA, and CK19 showed no evident difference on different gender, age, or tumor size. CD34 was negatively correlated with PCNA and positively correlated with CK19. CONCLUSIONS: AFP- hepatocellular carcinoma patients with FNH showed high CD34 and CK19, and low PCNA level.

In Vitro Expression of Cytokeratin 19 in Adipose-Derived Stem Cells Is Induced by Epidermal Growth Factor.

BACKGROUND Cytokeratin 19 (CK19) is a typical epithelial marker. In this study, we determined whether epidermal growth factor (EGF) or basic fibroblast growth factor (bFGF) could enhance CK19 expression in adipose-derived stem cells (ADSCs), thereby inducing the differentiation of ADSCs into epithelial-like cells. MATERIAL AND METHODS ADSCs were isolated from perinephric fat, and the expression of CD29, CD90, and CD105 was confirmed. Following isolation, ADSCs were cultured in static medium or medium containing EGF or bFGF. RESULTS Flow cytometry revealed that EGF and bFGF could alter mesenchymal stem cell markers as well as the cell cycle of ADSCs. Western blotting and immunofluorescence revealed that after 14 days, EGF treatment enhanced the expression of CK19 in ADSCs. CONCLUSIONS Our findings offer important insight for the clinical use of ADSCs in the generation of epithelial-like cells in the future.

Immunohistochemical and electron microscopic morphometric image analysis of hepatocellular carcinoma in association of HCV infection.

Early detection of hepatocellular carcinoma (HCC) is crucial for successful therapy. The present work examined the value of ultrastructural morphometric image analysis of hepatocyte nuclei in patients with chronic hepatitis C virus (HCV) versus HCC cases with chronic HCV and the corresponding surgical tumor-free safe margins (TFMs), to highlight any early predictive signs of neoplastic cellular transformation. This work also performed an immunohistochemical assessment of cytokeratin 19 (CK19) and Ki-67-positive cells to visualize any associated proliferative activity in the examined groups. The results showed significant decrease in the hepatocyte nuclear surface areas in the HCC and TFMs versus those in the HCV cases. The hepatocyte nucleolar surface area was significantly increased in the HCC cases versus that in the HCV cases. This increase was associated with a significant increase in Ki-67-positive cells in the HCC cases compared to those in the other groups. Conversely, the mean number of CK 19-positive cells was significantly reduced in the HCC cases compared to the cell numbers in TFMs and HCV cases with severe hepatic fibrosis. Liver progenitor cells (LPCs) were discerned in the reactive ductules and canaliculo-ductular junctions that characterized TFMs. LPCs were sporadically distributed in the liver lobules and reactive bile ductules in the HCC samples. In conclusion, CK 19 represents an important marker for distinguishing between dysplastic and malignant liver nodules. Electron microscopic morphometric image analysis may be considered as adjunct factor for assessing hepatocyte malignant transformation. Wider scale studies are needed to authenticate these results.

Neuron-specific enolase, histopathological types, and age as risk factors for bone metastases in lung cancer.

Lung cancer is a malignant tumor with high metastatic ability and bone is the most common site of distant metastasis of it. However, the independent risk factors for bone metastases of lung cancer remain largely to be elucidated. Here, we conducted a retrospective study to evaluate the correlation between clinical-pathological parameters, serum levels of neuron-specific enolase and CYFRA21-1, and bone metastases in lung cancer patients. The results revealed that patients with bone metastases were younger than those without metastases. Adenocarcinoma was the most frequent type of histopathology in patients with bone metastases. And the incidence of bone metastasis in patients with adenocarcinoma was significantly higher than those with other histopathological subtypes ( p < 0.001). Furthermore, the serum concentration of neuron-specific enolase was significantly higher in patients with bone lesions than those without bone metastases. Multivariate logistic regression analysis showed that patients' age (odds ratio = 1.024, p < 0.001), concentrations of neuron-specific enolase (odds ratio = 1.212, p = 0.004), and histopathological types (odds ratio = 0.995, p = 0.001) were the independent risk factors for bone metastases in patients with lung cancer. Thus, physicians should pay attention to these factors in order to identify bone metastasis earlier while patient was primarily diagnosed as having lung cancer.

Diagnostic value of TROP-2 expression in papillary thyroid carcinoma and comparison with HBME-1, galectin-3 and cytokeratin 19.

In this study, we compared the diagnostic value of TROP-2 expression in distinguishing between benign and malignant thyroid lesions to those of HBME-1, CK19 and galectin-3. We selected 102 cases from our archive including 20 normal thyroid tissues, 23 follicular nodular diseases, 17 follicular adenomas, 20 follicular variant papillary carcinomas and 22 classical variant papillary carcinomas. Tissue microarrays constructed from these cases were immunohistochemically analyzed with HBME-1, CK19, galectin-3 and TROP-2. Respectively 73.8%, 83.3%, 69% and 50% of all papillary carcinomas were positive with HBME-1, CK19, galectin-3 and TROP-2. CK19 was positive respectively by 100%, 43.5% and 35.3% in cases of normal thyroid, follicular nodular diseases and follicular adenoma, while the other markers were negative. In distinguishing benign and malignant lesions, which constitutes this study, HBME-1, CK19, galectin-3 and TROP-2 were statistically significant (p < 0.001). In distinguishing cases of follicular variant papillary carcinoma from follicular nodular diseases and follicular adenoma, HBME-1 and galectin-3 were statistically significant (p < 0.001). Consequently, in this study, we found that all immunohistochemical markers were effective in distinguishing benign and malignant thyroid lesions. In determining malignancy, HBME-1 had the highest diagnostic accuracy, while CK19 was the most sensitive marker. The sensitivity increased when the markers were used together.

Structure of neuro-endocrine and neuro-epithelial interactions in human foetal pancreas.

In the pancreas of many mammals including humans, endocrine islet cells can be integrated with the nervous system components into neuro-insular complexes. The mechanism of the formation of such complexes is not clearly understood. The present study evaluated the interactions between the nervous system components, epithelial cells and endocrine cells in the human pancreas. Foetal pancreas, gestational age 19-23 weeks (13 cases) and 30-34 weeks (7 cases), were studied using double immunohistochemical labeling with neural markers (S100 protein and beta III tubulin), epithelial marker (cytokeratin 19 (CK19)) and antibodies to insulin and glucagon. We first analyse the structure of neuro-insular complexes using confocal microscopy and provide immunohistochemical evidences of the presence of endocrine cells within the ganglia or inside the nerve bundles. We showed that the nervous system components contact with the epithelial cells located in ducts or in clusters outside the ductal epithelium and form complexes with separate epithelial cells. We observed CK19-positive cells inside the ganglia and nerve bundles which were located separately or were integrated with the islets. Therefore, we conclude that neuro-insular complexes may forms as a result of integration between epithelial cells and nervous system components at the initial stages of islets formation.

Glypican-3 and KRT19 are markers associating with metastasis and poor prognosis of pancreatic ductal adenocarcinoma.

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor with metastasis in most patients at diagnosis. The molecular mechanisms associated with its high malignancy have not been fully elucidated. This study investigated the clinicopathological significances of GPC3 and KRT19 expression in PDAC. METHODS: GPC3, KRT19, and CA19-9 protein expression were measured by immunohistochemistry. RESULTS: GPC3 and KRT19 protein levels were overexpressed in PDAC tumors compared to normal pancreatic tissues, benign pancreatic tissues, and peritumoral tissues (P< 0.01). The percentage of positive GPC3 and KRT19 expression were significantly higher in PDAC patients with larger tumor size, poorly differentiated tumor, lymph node metastasis, invasion, and TNM stage III/IV disease than in patients with small tumor size, well-differentiated tumor, no lymph node metastasis and invasion, as well as TNM stage I/II stage disease (P< 0.05 or P< 0.01). Benign pancreatic lesions with positive GPC3 and KRT19 protein expression exhibited dysplasia or intraepithelial neoplasia. Kaplan-Meier survival analysis showed that PDAC patients with positive GPC3 and KRT19 expression survived significantly shorter than patients with negative GPC3 and KRT19 expression (P < 0.05 or P< 0.001). Cox multivariate analysis revealed that positive GPC3 and KRT19 expression were independent poor prognosis factors in PDAC patients. CONCLUSIONS: GPC3 and KRT19 overexpression are associated with carcinogenesis, progression, and poor prognosis in patients with PDAC and a valuable biomarker for diagnosis of PDAC.

Epigenetic modifications in salivary glands from patients with Sjögren's syndrome affect cytokeratin 19 expression.

Sjögren's syndrome (SS) is a chronic autoimmune epithelitis, and several lines of experiments indicate that multifactorial factors contribute to salivary gland epithelial cells (SGEC) dysfunctions including a combination of environmental factors, lymphocytic infiltrations, genetic predispositions as well as epigenetic defects. Such statement is reinforced by the observation that global DNA methylation (5MeCyt) is altered in minor salivary glands from pSS patients and that such defect is associated cytokeratin 19 (KRT19) overexpression. An epigenetic deregulation of the KRT19 gene was further tested by treating the human salivary gland (HSG) cell line with the DNA demethylating agent 5-azacytidin, and with the histone acetylase inhibitor trichostatin A. Blocking DNA methylation, but not histone acetylation, with 5-azacytidin was associated with KRT19 overexpression at both transcriptional and protein level. Next, analysis of the CpG genome-wide methylome array in the KTR19 locus from long term cultured SGEC obtained from 8 pSS patients revealed a more reduced DNA methylation level in those patients with defective global DNA methylation. Altogether, our data, therefore, suggest that alteration of DNA methylation in SGEC may contribute to pSS pathophysiology in part by controlling the expression of KRT19.

Comparison of the Diagnostic Value Between Real-Time Reverse Transcription-Polymerase Chain Reaction Assay and Histopathologic Examination in Sentinel Lymph Nodes for Patients With Gastric Carcinoma.

OBJECTIVES: Sentinel lymph node (SLN)-based diagnosis in gastric cancers has shown varied sensitivities and false-negative rates in several studies. Application of the reverse transcription-polymerase chain reaction (RT-PCR) in SLN diagnosis has recently been proposed. METHODS: A total of 155 SLNs from 65 patients with cT1-2, N0 gastric cancer were examined. The histopathologic results were compared with results obtained by real-time RT-PCR for detecting molecular RNA (mRNA) of cytokeratin (CK)19, carcinoembryonic antigen (CEA), and CK20. RESULTS: The sensitivity and specificity of the multiple marker RT-PCR assay standardized against the results of the postoperative histological examination were 0.778 (95% confidence interval [CI], 0.577-0.914) and 0.781 (95% CI, 0.700-0.850), respectively. In comparison, the sensitivity and specificity of intraoperative diagnosis were 0.819 (95% CI, 0.619-0.937) and 1.000 (95% CI, 0.972-1.000), respectively. The positive predictive value of the multiple-marker RT-PCR assay was 0.355 (95% CI, 0.192-0.546) for predicting non-SLN metastasis, which was lower than that of intraoperative diagnosis (0.813, 95% CI, 0.544-0.960). CONCLUSIONS: The real-time RT-PCR assay could detect SLN metastasis in gastric cancer. However, the predictive value of the real-time RT-PCR assay was lower than that of precise histopathologic examination and did not outweigh that of our intraoperative SLN diagnosis.

CK19 and Glypican 3 Expression Profiling in the Prognostic Indication for Patients with HCC after Surgical Resection.

This retrospective study was designed to investigate the correlation between a novel immunosubtyping method for hepatocellular carcinoma (HCC) and biological behavior of tumor cells. A series of 346 patients, who received hepatectomy at two surgical centers from January 2007 to October 2010, were enrolled in this study. The expressions of cytokeratin 19 (CK19), glypican 3 (GPC3), and CD34 were detected by immunohistochemical staining. The clinical stage was assessed using the sixth edition tumor-node-metastasis (TNM) system (UICC/AJCC, 2010).Vascular invasion comprised both microscopic and macroscopic invasion. The tumor size, lymph node involvement, and metastasis were determined by pathological as well as imaging studies. Recurrence was defined as the appearance of new lesions with radiological features typical of HCC, seen by at least two imaging methods. Survival curves for the patients were plotted using the Kaplan-Meier method, and differences between the curves were assessed using the log-rank test. Significant differences in morphology, histological grading, and TNM staging were observed between groups. Based on the immunohistochemical staining, the enrolled cases were divided into CK19+/GPC3+, CK19-/GPC3+ and CK19-/GPC3- three subtypes. CK19+/GPC3+ HCC has the highest risk of multifocality, microvascular invasion, regional lymph node involvement, and distant metastasis, followed by CK19-/GPC3+ HCC, then CK19-/GPC3-HCC. CK19+/GPC3+ HCC has the shortest recurrence time compared to other immunophenotype HCCs. CK19 and GPC3 expression profiling is an independent prognostic indicator in patients with HCC, and a larger sample size is needed to further investigate the effect of this immunosubtyping model in stratifying the outcome of HCC patients.

Cells of Benign and Borderline Thyroid Tumor Express Malignancy Markers.

We studied expression of malignancy markers galectin-3, cytokeratin-19, HBME-1, fibronectin, and cyclin D1 in cells of benign (n=51), malignant (n=87), and borderline (n=53) tumors. The results indicate that 3.9% benign and 41.5% borderline tumors express malignancy markers (specificity 98-100%). Follow up over 1-10 years after surgical treatment for borderline tumors showed no progression of tumor growth. We conclude that some benign and borderline tumors represent low-grade neoplasms with favorable prognosis.

Nucleus pulposus phenotypic markers to determine stem cell differentiation: fact or fiction?

Progress in mesenchymal stem cell (MSC) based therapies for nucleus pulposus (NP) regeneration are hampered by a lack of understanding and consensus of the normal NP cell phenotype. Despite the recent consensus paper on NP markers, there is still a need to further validate proposed markers. This study aimed to determine whether an NP phenotypic profile could be identified within a large population of mature NP samples.qRT-PCR was conducted to assess mRNA expression of 13 genes within human non-degenerate articular chondrocytes (AC) (n=10) and NP cells extracted from patients across a spectrum of histological degeneration grades (n=71). qRT-PCR results were used to select NP marker candidates for protein expression analysis.Differential expression at mRNA between AC and non-degenerate NP cells was only observed for Paired Box Protein 1 (PAX1) and Forkhead box F1 (FOXF1). In contrast no other previously suggested markers displayed differential expression between non-degenerate NP and AC at mRNA level. PAX1 and FOXF1 protein expression was significantly higher in the NP compared to annulus fibrosus (AF), cartilaginous endplate (CEP) and AC. In contrast Laminin-5 (LAM-332), Keratin-19 (KRT-19) and Hypoxia Inducible Factor 1 alpha (HIF1α) showed no differential expression in NP cells compared with AC cells.A marker which exclusively differentiates NP cells from AF and AC cells remains to be identified, raising the question: is the NP a heterogeneous population of cells? Or does the natural biological variation during IVD development, degeneration state and even the life cycle of cells make finding one definitive marker impossible?

Expression of cytokeratin-19 (CK19) in the classical subtype of papillary thyroid carcinoma: the experience of one center in the Silesian region.

INTRODUCTION: Cytokeratin-19 (CK19) is recognized as a reliable tumor marker of papillary thyroid carcinoma (PTC). The general prognosis in the classical subtype of PTC (CSTPTC) remains favorable, but some cases can be very aggressive. The aim of this study was to evaluate the localization and intensity of immunohistochemical CK19 expression in CSTPTC and its associations with the clinical and pathological characteristics of patients with CSTPTC in the Silesian region. MATERIAL AND METHODS: All the available clinical and histopathological data for 149 patients with CSTPTC from the Silesian region were retrospectively analyzed. The group consisted of 135 (90.6%) women and 14 (9.4%) men (mean age and SD: 52.3 ± 15.0). All these patients with CSTPTC underwent surgery at the same center between 2008 and 2013; the follow-up period was 24 to 90 months (mean and SD: 47 ± 20). RESULTS: In 142 (95.3%) of the patients with CSTPTC, positive cytoplasmic staining of CK19 was found. A higher expression of CK19 was observed in the group of patients without the recurrence of the disease (p = 0.015). CK19 expression was not associated with age, gender, tumor focality, disease stage, tumor size (pT), lymph node involvement (pN), or distant metastases (pM). CONCLUSIONS: Decreased CK19 expression in CSTPTC cases with relapse suggests that it plays a role in the carcinoma progression of CSTPTC. The association between lower CK19 expression and patients' unfavorable postoperative course could suggest its possible role as a marker of CSTPTC poor prognosis.

Diagnostic and predictive significance of serum microRNA-7 in esophageal squamous cell carcinoma.

MicroRNA-7 has been reported to participate in tumorigenesis and progression by several signaling pathways in various tumors. However, its potential as a serum diagnostic factor and predictive biomarker for esophageal squamous cell carcinoma (ESCC) has not been studied. Serum samples were collected from 105 pathologically proven ESCC patients and 30 age- and gender-matched healthy controls. All patients were treated with concurrent chemoradiotherapy (CRT). Real­time polymerase chain reaction was carried out to measure the serum miR-7 expression level. The data were compared among radio-sensitive and radio-resistant groups, and healthy volunteers to elucidate the diagnostic and predictive value of miR-7 expression. Finally, in vitro experiments are used to clarify the mechanisms of the miR-7. In the present study, we found that the serum miR-7 level of ESCC patients was 4.74-fold lower as compared with healthy subjects, indicating that serum miR-7 expression could be an excellent diagnostic factor. The serum miR-7 expression level for these responsive patients was 2.34­fold higher than that for non-responsive patients, indicating it as a valuable biomarker for predicting treatment response of ESCC patients to concurrent chemoradiation treatment. We also found that miR-7 levels are strongly correlated with tumor length and the status of lymph node metastasis (P<0.05). In contrast, the responsiveness of therapy is significantly correlated with CEA (P<0.05), Cyfra21-1 (P<0.05), serum miR-7 level (P<0.05) and myelosuppression (P<0.01). In addition, the experimental data also suggest that miR-7 can interfere with EGFR mRNA translation. In ESCC patients, serum miR-7 has the potential to serve as a noninvasive biomarker of diagnosis and predicting treatment responses to concurrent chemoradiation therapy. ESCC patients with lower Cyfra21-1 and CEA, higher miR-7 and severe myelosuppression were much more sensitive to CRT. In addition, miR-7 may function by interfering with EGFR mRNA translation, but not degradation.

Cancer stem cells in hepatocellular carcinoma--an immunohistochemical study with histopathological association.

BACKGROUND & OBJECTIVES: Cancer stem cells (CSCs) may be responsible for tumour recurrence and resistance to chemotherapy in hepatocellular carcinoma (HCC). This study was carried out to evaluate the association between histological parameters and liver CSCs (LCSC) in HCC, and to compare distribution of liver CSCs in HCC associated with and without hepatitis B virus (HBV) infection. METHODS: Seventy nine tumours (49 surgical resections from 46 patients, and 30 from autopsy) were reviewed. Immunohistochemical staining for the LCSC marker EpCAM (epithelial cell adhesion molecule), liver progenitor cell (LPC) markers CK19 (cytokeratin 19) and neural cell adhesion molecule (NCAM) were performed and were associated with histological features of tumour behaviour. RESULTS: Thirty three tumours (41.8%) showed positive staining for EpCAM. CK19 and NCAM expression were seen in 26 (32.9%) and four (5.1%) tumours, respectively. The expression of EpCAM and CK19 was significantly associated with each other ( P<0.001). EpCAM expression was significantly associated with clinical and histological features indicating aggressive tumour behaviour, including younger age of onset, higher serum alpha foetoprotein (AFP) levels, tumour cell dedifferentiation, increased mitotic activity, and vascular invasiveness. There was no significant difference in expression of EpCAM, CK19 and NCAM between HBV positive and negative HCC. INTERPRETATION & CONCLUSIONS: The LCSC marker EpCAM was expressed in less than half of HCC, was independent of HBV aetiology, and was strongly associated with clinical and histological features of aggressive tumour behaviour. Positive staining for CK19 suggests a possible LPC origin of the EpCAM positive HCCs.

Cytokeratin-19 positivity is acquired along cancer progression and does not predict cell origin in rat hepatocarcinogenesis.

UNLABELLED: Although the expression of the stem/progenitor cell marker cytokeratin-19 (CK-19) has been associated with the worst clinical prognosis among all HCC subclasses, it is yet unknown whether its presence in HCC is the result of clonal expansion of hepatic progenitor cells (HPCs) or of de-differentiation of mature hepatocytes towards a progenitor-like cell phenotype. We addressed this question by using two rat models of hepatocarcinogenesis: the Resistant-Hepatocyte (R-H) and the Choline-methionine deficient (CMD) models. Our data indicate that the expression of CK-19 is not the result of a clonal expansion of HPCs (oval cells in rodents), but rather of a further step of preneoplastic hepatocytes towards a less differentiated phenotype and a more aggressive behavior. Indeed, although HCCs were positive for CK-19, very early preneoplastic foci (EPFs) were completely negative for this marker. While a few weeks later the vast majority of preneoplastic nodules remained CK-19 negative, a minority became positive, suggesting that CK-19 expression is the result of de-differentiation of a subset of EPFs, rather than a marker of stem/progenitor cells. Moreover, the gene expression profile of CK-19-negative EPFs clustered together with CK-19-positive nodules, but was clearly distinct from CK-19 negative nodules and oval cells. CONCLUSIONS: i) CK-19-positive cells are not involved in the early clonal expansion observed in rat hepatocarcinogenesis; ii) CK-19 expression arises in preneoplastic hepatocyte lesions undergoing malignant transformation; iii) CK-19 positivity in HCCs does not necessarily reflect the cell of origin of the tumor, but rather the plasticity of preneoplastic cells during the tumorigenic process.

Immunotherapy for Lewis lung carcinoma utilizing dendritic cells infected with CK19 gene recombinant adenoviral vectors.

Dendritic cells (DCs) as 'professional' antigen-presenting cells (APCs) initiate and regulate immune responses to various antigens. DC-based vaccines have become a promising modality in cancer immunotherapy. Cytokeratin 19 (CK19) protein is expressed at high levels in lung cancer and many other tumor cells, suggesting CK19 as a potential tumor­specific target for cancer immune therapy. We constructed a recombinant adenoviral vector containing the CK19 gene (rAd-CK19). DCs transfected with rAd-CK19 were used to vaccinate C57BL/6 mice bearing xenografts derived from Lewis lung carcinoma (LLC) cells. The transfected DCs gave rise to potent CK19-specific cytotoxic T lymphocytes (CTLs) capable of lysing LLC cells. Mice immunized with the rAd­CK19-DCs exhibited significantly attenuated tumor growth (including tumor volume and weight) when compared to the tumor growth of mice immunized with rAd-c DCs or DCs during the 24-day observation period (P<0.05). The results revealed that the mice vaccinated with the rAd-CK19-DCs exhibited a potent protective and therapeutic antitumor immunity to LLC cells in the subcutaneous model along with an inhibitive effect on tumor growth compared to the mice vaccinated with the rAd-c DCs or DCs alone. The present study proposes a meaningful mode of action utilizing rAd-CK19 DCs in lung cancer immunotherapy.