From proteomic analysis to clinical significance: overexpression of cytokeratin 19 correlates with hepatocellular carcinoma metastasis

Serum CYFRA 21-1 and CK19-2G2 as Predictive Biomarkers of Response to Transarterial Chemoembolization in Hepatitis C-related Hepatocellular Carcinoma Among Egyptians: A Prospective Study

Background and aim

Cytokeratin 19 (CK19)-positive HCC is a subtype of hepatocellular carcinoma (HCC) with poor biological behavior and resistance to different treatments including transarterial chemoembolization (TACE). The current study aimed to investigate the predictive value of serum CK 19 fragment 21-1 (CYFRA 21-1) and serum CK 19 fragment 2G2 (CK 19-2G2) for TACE response in patients with hepatitis C virus (HCV)-related HCC.

Methods

This prospective study assessed the pretreatment serum CYFRA 21-1 and CK 19-2G2 levels in 64 patients with HCV-related naïve HCC who underwent TACE to predict 1-year overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Additionally, 40 healthy individuals were included as controls. Pretreatment alpha-fetoprotein (AFP) was also measured for comparison.

Results

After exclusions, 60 patients completed TACE sessions, and the 1-year OS was 52%, and ORR post TACE was 71.8%. HCC patients with elevated levels of CYFRA 21-1, CK 19-2G2, or baseline AFP measuring ≥400 ng/ml have decreased 1-year OS and PFS after TACE. Serum CK19-2G2 was an independent predictor of 1-year OS using multivariate hazard regression analysis. Pretreatment normal serum CYFRA 21-1 levels (P = 0.047), serum AFP measuring <400 ng/ml (P = 0.016), and lower AST (P = 0.002) were independent predictors of ORR to TACE using multivariate logistic regression analysis. The predictive ability of pretreatment elevated serum CYFRA 21-1, AFP measuring ≥400 ng/ml, AFP + CYFRA 21-1, AFP + CK 19-2G2, or AFP + CYFRA 21-1+ CK19-2G2 to predict nonresponse (progressive disease) to TACE (area under the curve = 0.795, 0.690, 0.830, 0.725, and 0.850, respectively).

Conclusions

This study demonstrated that incorporating the measurement of serum CYFRA 21-1 or CK19-2G2 levels, along with AFP, during the initial diagnosis can aid in predicting poor 1-year OS, PFS, and ORR to TACE in patients with HCV-related HCC.

Pathology of Combined Hepatocellular Carcinoma-Cholangiocarcinoma: An Update

Combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA) is a rare primary liver cancer that is composed of both hepatocellular and cholangiocellular differentiated cells. It is slightly more common in men and among Asian and Pacific islanders. Overall, risk factors are similar to classic risk factors of hepatocellular carcinoma (HCC). The classification has significantly evolved over time. The last WHO classification (2019) mainly emphasized diagnosis on morphological basis with routine stainings, discarded previously recognized classifications with carcinomas with stem cell features, introduced intermediate cell carcinoma as a specific subtype and considered cholangiolocarcinoma as a subtype of cholangiocellular carcinoma. Immunohistochemical markers may be applied for further specification but have limited value for diagnosis. Recent discoveries in molecular pathway regulation may pioneer new therapeutic approaches for this poor prognostic and challenging diagnosis.

In Vivo Modeling of Human Breast Cancer Using Cell Line and Patient-Derived Xenografts

Historically, human breast cancer has been modeled largely in vitro using long-established cell lines primarily in two-dimensional culture, but also in three-dimensional cultures of varying cellular and molecular complexities. A subset of cell line models has also been used in vivo as cell line-derived xenografts (CDX). While outstanding for conducting detailed molecular analysis of regulatory mechanisms that may function in vivo, results of drug response studies using long-established cell lines have largely failed to translate clinically. In an attempt to address this shortcoming, many laboratories have succeeded in developing clinically annotated patient-derived xenograft (PDX) models of human cancers, including breast, in a variety of host systems. While immunocompromised mice are the predominant host, the immunocompromised rat and pig, zebrafish, as well as the chicken egg chorioallantoic membrane (CAM) have also emerged as potential host platforms to help address perceived shortcomings of immunocompromised mice. With any modeling platform, the two main issues to be resolved are criteria for "credentialing" the models as valid models to represent human cancer, and utility with respect to the ability to generate clinically relevant translational research data. Such data are beginning to emerge, particularly with the activities of PDX consortia such as the NCI PDXNet Program, EuroPDX, and the International Breast Cancer Consortium, as well as a host of pharmaceutical companies and contract research organizations (CRO). This review focuses primarily on these important aspects of PDX-related research, with a focus on breast cancer.

Decreased ARG1 expression as an adverse prognostic phenotype in non-alcoholic non-virus-related hepatocellular carcinoma

The incidence of non-alcoholic non-virus-related hepatocellular carcinoma (NANV-HCC) is increasing along with the growing prevalence of metabolic disorders. In this subset, few useful biomarkers are available to narrow down the high-risk group for recurrence. This study aimed to evaluate the prognostic impact of decreased ARG1 (arginase-1), which is pathologically known as a marker reflecting hepatocyte differentiation, in NANV-HCC. Besides, its relationship with biliary/progenitor cell markers, whose expressions are associated with poor prognosis, was also assessed. To reveal the clinicopathological association of decreased ARG1 expression in NANV-HCC, we investigated 99 patients who underwent curative-intent hepatectomy for NANV-HCC. Tissue microarrays were employed for immunohistochemical analysis. A total of 21 NANV-HCC cases (21%; 21/99) showed decreased ARG1 expression. Decreased ARG1 expression was an independent prognostic factor for both poor DFS (hazard ratio 2.17; 95% confidence interval 1.15-4.09; p = 0.02) and OS (hazard ratio 4.09; 95% confidence interval 1.71-9.80; p = 0.002). In addition, decreased ARG1 expression was significantly associated with expressions of biliary/progenitor cell markers, CK19 and CD56 (p < 0.01). As cytologic features of tumor cells, decreased ARG1 expression was significantly associated with lipid-less cytologic morphology (p = 0.045). These findings indicate that decreased ARG1 expression is a predictive phenotype of postoperative recurrence with poor prognosis in patients with NANV-HCC. Decreased ARG1 expression may be a precursor or overlapping feature with biliary/progenitor cell marker expressions in NANV-HCC.

Potential Biomarkers for Liver Cancer Diagnosis Based on Multi-Omics Strategy

Liver cancer is the fourth leading cause of cancer-related death worldwide. Hepatocellular carcinoma (HCC) accounts for about 85%-90% of all primary liver malignancies. However, only 20-30% of HCC patients are eligible for curative therapy mainly due to the lack of early-detection strategies, highlighting the significance of reliable and accurate biomarkers. The integration of multi-omics became an important tool for biomarker screening and unique alterations in tumor-associated genes, transcripts, proteins, post-translational modifications and metabolites have been observed. We here summarized the novel biomarkers for HCC diagnosis based on multi-omics technology as well as the clinical significance of these potential biomarkers in the early detection of HCC.

CK19 Predicts Recurrence and Prognosis of HBV Positive HCC

BACKGROUND

Cytokeratin is associated with the recurrence and metastasis of some cancers and tends to increase the malignancy of the disease. It is getting more and more attention in cancer research. Abnormal expression of cytokeratin 19 (CK19) has been reported as an important prognostic factor in cancers. CK19 is a marker of bile duct cells, liver progenitor cells (HPCs), and early hepatoblasts, and its expression is associated with poor prognosis in patients diagnosed with hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the predictive value of CK19 for tumor recurrence after radical resection in patients with hepatitis B virus (HBV) positive HCC.

METHODS

This study was a retrospective study conducted in two institutions. A total of 674 patients with HBV positive HCC who underwent radical HCC resection from January 2010 to May 2020 were included in this study. Chi-square test or Fisher's exact test was used to compare the classification variables and continuous variables were compared by t-test or Wilcoxon rank sum test. Cox regression model was used for univariate and multi-variable survival analyses. Based on the results of the multi-variable analyses of Cox regression, the nomogram of 2-year recurrence-free survival (RFS) was plotted. The model was validated internally in the Hangzhou cohort (training set) and then externally in the Lanzhou cohort (test set) and the effectiveness of the model was tested.

RESULTS

For all 674 patients, 223 cases (33.1%) were positive and 451 cases (66.9%) were negative for CK19. The 2-year RFS rate was higher in patients with CK19 negative than in patients with CK19 positive. In the training set, correlation analysis showed that CK19 expression was correlated with preoperative potassium (P value(P) = 0.030), satellite nodules (P < 0.001) and microvascular invasion (P = 0.020). In the test set, CK19 expression was correlated with postoperative platelet (P = 0.038), satellite nodules (P = 0.003), microvascular invasion (P = 0.011), and maximum tumor size (P = 0.039). Univariate Cox regression correlation analyses showed that CK19 expression was correlated with preoperative potassium (P value(P) = 0.030), satellite nodules (P < 0.001), and microvascular invasion (P = 0.020). Training and test sets showed that postoperative platelet (> 300/L), CK19, satellite nodules in the training set, microvascular invasion, maximum tumor size, and tumor boundary were adverse factors for predicting RFS. Multi-variable analyses showed that in the training set, postoperative platelet > 300/L (hazard ratios (HR) = 2.753, 95% confidence interval (95%CI):1.234-6.142, P = 0.013), CK19 (HR = 1.410, 95%CI:1.006-1.976, P = 0.046), satellite nodule (HR = 1.476, 95%CI:1.026-2.120, P = 0.036), microvascular invasion (HR = 2.927, 95%CI:2.006-4.146, P < 0.001), incomplete tumor capsule (HR = 1.539, 95%CI:1.012-2.341, P = 0.044) were independent prognostic indicator of poor RFS. In the test set, postoperative platelet > 300/L (HR = 2.816, 95%CI:1.043-7.603, P = 0.041), CK19 (HR = 1.586, 95%CI:1.016-2.475, P = 0.042), satellite nodule (HR = 1.706, 95%CI:1.067-2.728, P = 0.026), microvascular invasion (HR = 1.611, 95%CI:1.034-2.510, P = 0.035), and tumor without capsule (HR = 1.870, 95%CI:1.120-3.120, P = 0.017) were independent prognostic indicators of poor RFS. The C-index for the nomogram was 0.698 (95%CI: 0.654-0.742) and the C-index for the test set was 0.670 (95%CI: 0.616-0.724). Both internal and external verification showed good results in identification and calibration.

CONCLUSION

CK19 plays a key role in tumor malignancy through overexpression and the expression of CK19 is an independent adverse factor affecting recurrence; therefore, CK19 can be used as a potential biomarker to predict adverse prognosis after surgery and adjuvant therapy in HCC patients.

Lung and lymph node metastases from hepatocellular carcinoma: Comparison of pathological aspects

BACKGROUND & AIMS

Extrahepatic metastasis from hepatocellular carcinoma (HCC) is a catastrophic event, yet organ-specific pathological characteristics of metastatic HCC remain unclear. We aimed to characterize the pathological aspects of HCC metastases to various organs.

METHODS

We collected intrahepatic HCC (cohort 1, n = 322) and extrahepatic metastatic HCC (cohort 2, n = 130) samples. Clinicopathological evaluation and immunostaining for K19, CD34, αSMA, fibroblast-associated protein (FAP), CAIX, VEGF, PD-L1, CD3, CD8, Foxp3, CD163 and epithelial-mesenchymal transition (EMT)-related markers were performed.

RESULTS

Independent factors for extrahepatic metastasis included BCLC stage B-C, microvascular invasion (MVI), vessels encapsulating tumour clusters (VETC)-HCC, K19 and FAP expression, and CD163+ macrophage infiltration (cohort 1, P < .05 for all). Lung metastases (n = 63) had the highest proportion of VETC-HCC and macrotrabecular-massive (MTM)-HCC. Lymph node metastases (n = 19) showed significantly high rates of EMT-high features, K19 expression, fibrous tumour stroma with αSMA and FAP expression, high immune cell infiltration, PD-L1 expression (combined positive score), CD3+, CD8+, Foxp3+ T cell and CD163+ macrophage infiltration (adjusted P < .05 for all). In both cohorts, EMT-high HCCs showed higher rates of K19 expression, fibrous tumour stroma, high immune cell infiltration, PD-L1 expression and CD3+ T cell infiltration, whereas EMT-low HCCs were more frequent among VETC-HCCs (P < .05 for all). Overall phenotypic features were not significantly different between paired primary-metastatic HCCs (n = 32).

CONCLUSIONS

Metastatic HCCs to various organs showed different pathological features. VETC and MTM subtypes were related to lung metastasis, whereas K19 expression, EMT-high features with fibrous tumour stroma and high immune cell infiltration were related to lymph node metastasis.

Re-Recognizing the Cellular Origin of the Primary Epithelial Tumors of the Liver

The primary epithelial tumors of the liver (PETL) are composed of a series of heterogeneous tumors. Although the classification of PETLs has been updated several times by the World Health Organization, the cellular origins of some tumors in this family remain to be precisely depicted. In addition, certain tumors in different categories have similar histology, molecular phenotypes and biological characteristics, suggesting that they may have the same cellular origin. In this work, a narrative review method was adopted to review the relevant papers. By comparing the expression profiles of biomarkers of liver epithelium at different lineages and stages of differentiation, the cells-of-origin of some major members of the PETL family were reassessed. We propose that 1) hepatic adenomas, hepatocellular carcinomas (HCCs) and pure fetal hepatoblastomas (HBs) share the same spectrum in their cellular origin including the hepatocytic-committed progenitors (HCP) and their differentiated descendants. 2) Bile duct adenomas, peribiliary cysts and intrahepatic cholangiocellular carcinomas (ICCs) can share the same spectrum in their cellular origin including the cholangiocytic-committed progenitors (CCP) and their differentiated descendants. 3) The cells-of-origin of embryonal HBs include liver stem cells (LSCs), hepatoblasts, and transitional cells between them. Embryonal HB with small cell element, small cell undifferentiated HB and small cell neuroendocrine carcinoma of the liver can have the same or similar cells-of-origin from LSC. Embryonal HB lacking the small cell component of the LSC phenotype and presenting both hepatocytic and bile duct/ductule components may originate from actual hepatoblasts/hepatic progenitor cells (HPCs) as the combined HCC-ICC does. 4) Teratoid hepatoblastoma and mixed epithelial/mesenchymal HBs can be derived from the LSCs or even less committed extrahepatic pluripotent stem cell. 5) Many members of the PETLs family, including those derived from LSCs, hepatoblasts/HPCs, early HCPs and CCPs, have neuroendocrine potentiality. Except for those primary hepatic neuroendocrine tumor (PHNET) exhibit hepatocytic and/or cholangiocytic phenotypes, other PHNETs subtype may be derived from the descendants of LSC that differentiate towards the upper digestive tract, pancreas or other lineages.

Usefulness of Circulating CYFRA21-1 in Patients as a Biomarker in Patients Taking Sorafenib or Lenvatinib for Unresectable Hepatocellular Carcinoma

Background: This study investigated the impact of serum cytokeratin 19 fragment (CYFRA21-1) level on the clinical outcomes of patients with unresectable hepatocellular carcinoma (HCC) treated with sorafenib (SOR) or lenvatinib (LEN). Methods: A total of 71 cases with unresectable HCC taking SOR or LEN were included. Univariate and multivariate analyses were performed to identify the prognostic factors in patients taking SOR or LEN. Results: Among the 71 patients taking SOR or LEN, the frequency of cases showing high CYFRA21-1 levels after administration increased compared to before the administration. There was no association between the CYFRA21-1 level and the result of treatment response using modified Response Evaluation Criteria in Solid Tumors (mRECIST) 12 weeks after the administration. Univariate analysis identified a maximum intrahepatic tumor diameter of 70 mm or more, extrahepatic metastasis, baseline alpha-fetoprotein (AFP) ≥ 2000 ng/mL, baseline AFP-L3 index ≥ 15%, baseline des-gamma-carboxy prothrombin (DCP) ≥ 1000 mAU/mL, baseline CYFRA21-1 > 3.5 ng/mL, 12-week mRECIST progressive disease (PD), 12-week DCP ratio ≥ 4, 12-week CYFRA21-1 ratio ≥ 2, administration period less than 12 weeks, ALBI grade 3 at PD, and no additional treatment after discontinuation of SOR/LEN as prognostic factors. Multivariate analysis revealed that AFP-L3 index ≥ 15%, 12-week mRECIST PD, 12-week DCP ratio ≥ 4, 12-week CYFRA21-1 ratio ≥ 2, administration period less than 12 weeks, and no additional treatment after discontinuation of SOR/LEN were independent factors. Conclusions: Patients with a high CYFRA21-1 level at baseline tend to have poor prognosis, and patients with a high CYFRA21-1 ratio 12 weeks after administration have poor prognosis. Serum CYFRA21-1 measurement may have additional effects on prognostic prediction, and it may be necessary to pay close attention to the transition to the next HCC treatment in cases whose CYFRA21-1 level is high.

Targeting the cytoskeleton against metastatic dissemination

Cancer is a pathology characterized by a loss or a perturbation of a number of typical features of normal cell behaviour. Indeed, the acquisition of an inappropriate migratory and invasive phenotype has been reported to be one of the hallmarks of cancer. The cytoskeleton is a complex dynamic network of highly ordered interlinking filaments playing a key role in the control of fundamental cellular processes, like cell shape maintenance, motility, division and intracellular transport. Moreover, deregulation of this complex machinery contributes to cancer progression and malignancy, enabling cells to acquire an invasive and metastatic phenotype. Metastasis accounts for 90% of death from patients affected by solid tumours, while an efficient prevention and suppression of metastatic disease still remains elusive. This results in the lack of effective therapeutic options currently available for patients with advanced disease. In this context, the cytoskeleton with its regulatory and structural proteins emerges as a novel and highly effective target to be exploited for a substantial therapeutic effort toward the development of specific anti-metastatic drugs. Here we provide an overview of the role of cytoskeleton components and interacting proteins in cancer metastasis with a special focus on small molecule compounds interfering with the actin cytoskeleton organization and function. The emerging involvement of microtubules and intermediate filaments in cancer metastasis is also reviewed.

Tandem Mass Tag-Based Proteomic Analysis of Potential Biomarkers for Hepatocellular Carcinoma Differentiation

Purpose

The poor prognosis of hepatocellular carcinoma (HCC) urgent us to discover early and effective biomarkers. In this study, we applied tandem mass tag (TMT)-based proteomic analysis to discover potential protein markers for HCC identification and differentiation.

Patients and Methods

Fifteen patients, well-differentiated (G1, N = 5), moderate-differentiated (G2, N = 5), and poorly differentiated (G3, N = 5), with 30 matched pair tissues (both tumor and adjacent non-tumor tissues derived from the same patient) were enrolled. All samples were subjected to TMT labeling and LC−MS/MS analysis. The identified proteins were subsequently assigned to GO and KEGG for predicting function. The identified protein candidates were validated using immunohistochemistry (IHC).

Results

A total of 1010 proteins were identified. Of these, 154 differentially expressed proteins (DEPs), 100 up-regulated and 54 down-regulated, were found between tumor and adjacent non-tumor tissues; 12 DEPs, 9 up-regulated and 3 down-regulated, were found between G1 and G3 tissues; 8 DEPs, 5 up-regulated and 3 down-regulated, were found between G1 and G2 tissues; 11 DEPs, 8 up-regulated and 3 down-regulated, were found between G2 and G3 tissues. Among them, ASS1 and CPS1 were significantly up-regulated while UROD and HBB were significantly down-regulated in G3 compared with G1 and G2 tumors. Three proteins, CYB5A, FKBP11 and YBX1, were significantly up-regulated in G1 compared with both G2 and G3 tumors. The 7 biomarker candidates were further verified by IHC.

Conclusion

A variety of DEPs related to the histological differentiation of HCC were identified, among which ASS1, CPS1, URPD and HBB proteins were potential biomarkers for distinguishing poorly differentiated HCC, while CYB5A, FKBP11 and YBX1 were potential biomarkers for distinguishing well-differentiated HCC. Our findings may further provide a new insight facilitating the diagnosis and prognosis of HCC.

Benefits and Detriments of Gadolinium from Medical Advances to Health and Ecological Risks

Gadolinium (Gd)-containing chelates have been established as diagnostics tools. However, extensive use in magnetic resonance imaging has led to increased Gd levels in industrialized parts of the world, adding to natural occurrence and causing environmental and health concerns. A vast amount of data shows that metal may accumulate in the human body and its deposition has been detected in organs such as brain and liver. Moreover, the disease nephrogenic systemic fibrosis has been linked to increased Gd³⁺ levels. Investigation of Gd³⁺ effects at the cellular and molecular levels mostly revolves around calcium-dependent proteins, since Gd³⁺ competes with calcium due to their similar size; other reports focus on interaction of Gd³⁺ with nucleic acids and carbohydrates. However, little is known about Gd³⁺ effects on membranes; yet some results suggest that Gd³⁺ interacts strongly with biologically-relevant lipids (e.g., brain membrane constituents) and causes serious structural changes including enhanced membrane rigidity and propensity for lipid fusion and aggregation at much lower concentrations than other ions, both toxic and essential. This review surveys the impact of the anthropogenic use of Gd emphasizing health risks and discussing debilitating effects of Gd³⁺ on cell membrane organization that may lead to deleterious health consequences.

Molecular mechanism underlying the difference in proliferation between placenta-derived and umbilical cord-derived mesenchymal stem cells

The placenta and umbilical cord are pre-eminent candidate sources of mesenchymal stem cells (MSCs). However, placenta-derived MSCs (P-MSCs) showed greater proliferation capacity than umbilical cord-derived MSCs (UC-MSCs) in our study. We investigated the drivers of this proliferation difference and elucidated the mechanisms of proliferation regulation. Proteomic profiling and Gene Ontology (GO) functional enrichment were conducted to identify candidate proteins that may influence proliferation. Using lentiviral or small interfering RNA infection, we established overexpression and knockdown models and observed changes in cell proliferation to examine whether a relationship exists between the candidate proteins and proliferation capacity. Real-time quantitative polymerase chain reaction, western blot analysis, and immunofluorescence assays were conducted to elucidate the mechanisms underlying proliferation. Six candidate proteins were selected based on the results of proteomic profiling and GO functional enrichment. Through further validation, yes-associated protein 1 (YAP1) and β-catenin were confirmed to affect MSCs proliferation rates. YAP1 and β-catenin showed increased nuclear colocalization during cell expansion. YAP1 overexpression significantly enhanced proliferation capacity and upregulated the expression of both β-catenin and the transcriptional targets of Wnt signaling, CCND1, and c-MYC, whereas silencing β-catenin attenuated this influence. We found that YAP1 directly interacts with β-catenin in the nucleus to form a transcriptional YAP/β-catenin/TCF4 complex. Our study revealed that YAP1 and β-catenin caused the different proliferation capacities of P-MSCs and UC-MSCs. Mechanism analysis showed that YAP1 stabilized the nuclear β-catenin protein, and also triggered the Wnt/β-catenin pathway, promoting proliferation.

Prognostic Role of Serum Cytokeratin-19 Fragment (CYFRA 21-1) in Patients with Hepatocellular Carcinoma

Keratin 19 (K19) is a cancer stem cell marker expressed by a subpopulation of hepatocellular carcinoma (HCC), associated with tumor aggressiveness. We evaluated the prognostic value of serum K19 fragment (CYFRA 21-1), in comparison or in combination with alpha-fetoprotein (AFP) and protein induced by vitamin-K absence or antagonist-II (PIVKA-II), in patients with HCC. A total of 160 patients (28F/132M; median age 62, range 44-86 years) with a new diagnosis of HCC and available serum samples collected at tumor diagnosis were analyzed retrospectively. Median overall survival (OS) after HCC diagnosis was 35.1, 95% CI 27.1-70.5 months. Multivariate Cox regression analysis showed that CYFRA 21-1 > 2.7 ng/mL (hazard ratio (HR) = 3.39, p < 0.001), AFP > 20 ng/mL (HR = 2.27, p = 0.007), and PIVKA-II > 200 mAU/mL (HR = 2.17, p = 0.020) were independent predictors of OS. The combination of biomarkers positivity allowed us to stratify patients with HCC into four risk categories associated with a progressively lower survival probability (log-rank test, p < 0.001). CYFRA 21-1 resulted an independent prognostic factor of patients with HCC and its combination with AFP and PIVKA-II might be useful to tailor personalized treatment strategies.

Phosphoglycerate kinase 1 (PGK1) in cancer: A promising target for diagnosis and therapy

Phosphoglycerate kinase 1 (PGK1) is the first critical enzyme to produce ATP in the glycolytic pathway. PGK1 is not only a metabolic enzyme but also a protein kinase, which mediates the tumor growth, migration and invasion through phosphorylation some important substrates. Moreover, PGK1 is associated with poor treatment and prognosis of cancers. This manuscript reviews the structure, functions, post-translational modifications (PTMs) of PGK1 and its relationship with tumors, which demonstrates that PGK1 has indispensable value in the tumor progression. The current review highlights the important role of PGK1 in anticancer treatments.

Expression pattern of placenta specific 8 and keratin 20 in different types of gastrointestinal cancer

The aim of the present study was to investigate the expression of keratin 20 (KRT20) and placenta specific 8 (PLAC8) in gastrointestinal (GI) cancer with various differentiation phenotypes. The present study retrospectively investigated archived formalin-fixed paraffin-embedded tissue samples from 12 patients at different stages of GI cancer [four with gastric cancer, four with pancreatic cancer and four with colorectal cancer (CRC)]. The stages were pre-determined, according to differentiation phenotypes, by a pathologist of the Department of Pathology at Sijhih Cathay General Hospital. KRT20 and PLAC8 expression levels were assessed using immunohistochemistry. The CRC cell lines SW620 and Caco-2 were used to assess interactions between KRT20 and PLAC8 via reverse transcription-quantitative PCR. PLAC8 and KRT20 expression was observed consistently only in the well-differentiated CRC tissue samples. Low KRT20 expression levels were observed in the PLAC8 knockdown SW620 cells. In addition, there was a positive association between PLAC8 and KRT20 expression in the differentiated Caco-2 cells. According to the results of the present study, the differentiation status of GI cancer influenced KRT20 expression, particularly in CRC, which may explain why patients with well-differentiated CRC display better clinical outcomes. Therefore, the prognostic significance of KRT20 and PLAC8 may be particularly crucial for patients with CRC displaying a well-differentiated phenotype.

Intermediate Filaments as Effectors of Cancer Development and Metastasis: A Focus on Keratins, Vimentin, and Nestin

Intermediate filament (IF) proteins make up the largest family of cytoskeletal proteins in metazoans, and are traditionally known for their roles in fostering structural integrity in cells and tissues. Remarkably, individual IF genes are tightly regulated in a fashion that reflects the type of tissue, its developmental and differentiation stages, and biological context. In cancer, IF proteins serve as diagnostic markers, as tumor cells partially retain their original signature expression of IF proteins. However, there are also characteristic alterations in IF gene expression and protein regulation. The use of high throughput analytics suggests that tumor-associated alterations in IF gene expression have prognostic value. Parallel research is also showing that IF proteins directly and significantly impact several key cellular properties, including proliferation, death, migration, and invasiveness, with a demonstrated impact on the development, progression, and characteristics of various tumors. In this review, we draw from recent studies focused on three IF proteins most associated with cancer (keratins, vimentin, and nestin) to highlight how several “hallmarks of cancer” described by Hanahan and Weinberg are impacted by IF proteins. The evidence already in hand establishes that IF proteins function beyond their classical roles as markers and serve as effectors of tumorigenesis.

Evaluation of cytokeratin 19 as a prognostic tumoral and metastatic marker with focus on improved detection methods

In the last few years, there has been a growing interest in Cytokeratin 19 (CK19) studies in the cancer research field. CK19 belongs to the Type I CKs, serves as a useful research tool in prognosis, diagnosis, and management of the tumors. In this paper, we dissect the metastatic potential of CK19, its relation with cancer stem cells and retinal epithelial cells behavior, its application as a tumor marker and its role among 30 cancers such as thyroid, thoracic, lung, pancreatic, cervical, colorectal, and so forth. CK19 expressed in several cancer types because of its metastatic potential. This paper also presents modified detection methods of CK19 in disseminated tumor cells.

The Role of MicroRNAs in Hepatoblastoma Tumors

Hepatoblastoma is the most common hepatic malignancy during childhood. However, little is still known about the molecular mechanisms that govern the development of this disease. This review is focused on the recent advances regarding the study of microRNAs in hepatoblastoma and their substantial contribution to improv our knowledge of the pathogenesis of this disease. We show here that miRNAs represent valuable tools to identify signaling pathways involved in hepatoblastoma progression as well as useful biomarkers and novel molecular targets to develop alternative therapeutic strategies in this disease.

MiR-492 regulates metastatic properties of hepatoblastoma via CD44

BACKGROUND & AIMS

MicroRNAs are important genetic regulators of physiological and pathophysiological processes including cancer initiation and progression of hepatoblastoma, the most common liver tumour in childhood. We aimed to identify malignant and metastasis promoting effects of miR-492, a miRNA, previously reported to be overexpressed in metastatic hepatoblastoma. Furthermore, we intended to evaluate its diagnostic and prognostic potential.

METHODS

Stable and transient overexpression of miR-492 in two liver tumour cell lines HepT1 and HUH7 was used to analyse features of metastatic tumour progression such as proliferation, anchorage-independent growth, migration and invasion. Via a mass spectrometry based proteomic screen, we investigated miRNA-492-dependent effects on proteome level and explored the underlying biology. One of the predicted target genes, CD44, was experimentally validated via luciferase assays. Diagnostic and prognostic properties of miR-492 were studied in hepatoblastoma tumour samples.

RESULTS

We show that miR-492 significantly enhances cell proliferation, anchorage-independent growth, migration and invasion of hepatoblastoma cells. We also identified and validated CD44, a transmembrane adhesion receptor for hyaluronan, as direct and functional target of miR-492. This miRNA has a strong direct impact on two CD44 isoforms (standard and v10). High miR-492 expression correlates with high-risk or aggressive tumours and further bears potential for predicting reduced event-free survival.

CONCLUSIONS

We identified miR-492 and its target CD44 as regulators of a number of biological features important for malignancy and metastasis. Furthermore, we demonstrated the diagnostic and prognostic potential of miR-492, a promising novel therapeutic target and biomarker for hepatoblastoma.

Chronic inflammation-elicited liver progenitor cell conversion to liver cancer stem cell with clinical significance

The substantial heterogeneity and hierarchical organization in liver cancer support the theory of liver cancer stem cells (LCSCs). However, the relationship between chronic hepatic inflammation and LCSC generation remains obscure. Here, we observed a close correlation between aggravated inflammation and liver progenitor cell (LPC) propagation in the cirrhotic liver of rats exposed to diethylnitrosamine. LPCs isolated from the rat cirrhotic liver initiated subcutaneous liver cancers in nonobese diabetic/severe combined immunodeficient mice, suggesting the malignant transformation of LPCs toward LCSCs. Interestingly, depletion of Kupffer cells in vivo attenuated the LCSC properties of transformed LPCs and suppressed cytokeratin 19/Oval cell 6-positive tumor occurrence. Conversely, LPCs cocultured with macrophages exhibited enhanced LCSC properties. We further demonstrated that macrophage-secreted tumor necrosis factor-α triggered chromosomal instability in LPCs through the deregulation of ubiquitin D and checkpoint kinase 2 and enhanced the self-renewal of LPCs through the tumor necrosis factor receptor 1/Src/signal transducer and activator of transcription 3 pathway, which synergistically contributed to the conversion of LPCs to LCSCs. Clinical investigation revealed that cytokeratin 19/Oval cell 6-positive liver cancer patients displayed a worse prognosis and exhibited superior response to sorafenib treatment.

CONCLUSION

Our results not only clarify the cellular and molecular mechanisms underlying the inflammation-mediated LCSC generation but also provide a molecular classification for the individualized treatment of liver cancer. (Hepatology 2017;66:1934-1951).

Prognostic significance of serum procalcitonin in patients with unresectable hepatocellular carcinoma treated with transcatheter arterial chemoembolization: A retrospective analysis of 509 cases

Although procalcitonin (PCT) is a valid marker for early diagnosis of bacterial infections, its accuracy in hepatocellular carcinoma (HCC) patients is unknown. The aim of this study was to investigate the prognostic significance of PCT in patients with unresectable HCC treated with transcatheter arterial chemoembolization (TACE).A total of 509 patients with unresectable HCC initially treated with TACE were enrolled in this retrospective study. According to quartile of the PCT values, all patients were divided into 4 groups. Overall survival (OS) was evaluated with the Kaplan-Meier method. Significant difference was estimated with the Log rank method. Univariate and multivariate analyses were used for evaluating the significance of the prognostic factor.The median follow-up period was 18 months and there were significant differences in the survival rates between the 4 groups. The HR (95% CI) for all-cause mortality comparing patients with PCT Quartile2-4 to patient with Quartile1 (HR = 1.00) were 1.353 (1.023-1.791), 1.799 (1.354-2.390), 1.960 (1.455-2.639), respectively, (P < .001). PCT level was an important prognostic factor for predicting the prognosis of patients with unresectable HCC treated with TACE.

Screening and identification of the tumor-associated antigen CK10, a novel potential liver cancer marker

Hepatocellular carcinoma (HCC) is a malignancy that is associated with high mortality rates in Asia. These tumors are highly invasive and their etiology is frequently unknown. Thus, most patients are diagnosed in the middle and late stages of the disease, and thus do not have sufficient time for therapy. Therefore, it is essential to study the early diagnosis and treatment of HCC; in this regard, the study of tumor‐associated antigens has received much attention. Here, antigens from the human primary HCC cell line, QGY‐7703, were used to immunize mice in order to prepare monoclonal antibodies. The specific antigen recognized by antibody 11C3 was purified from total protein lysates of QGY‐7703 by immunoaffinity chromatography. The validity of the candidate antigen as a new HCC‐associated marker was tested using SDS/PAGE, western blot, HPLC‐ESI‐MS/MS, and RT‐qPCR. Our results showed that the levels of CK10 in HCC‐derived cell lines were significantly higher than those in normal liver cells. Thus, we suggest that CK10 may be involved in the formation and development of HCC, and may be a therapeutically targetable tumor‐associated antigen.

Diagnostic Value of CYFRA 21-1 in the Cerebrospinal Fluid for Leptomeningeal Metastasis

Cerebrospinal fluid (CSF) cytology has low sensitivity for leptomeningeal metastasis (LM); thus, new markers are needed to improve the diagnostic accuracy of LM. We measured carcinoembryonic antigen (CEA) and cytokeratin 19 fragments (CYFRA 21-1) in paired samples of CSF and serum from patients with LM and patients with nonmalignant neurological diseases (NMNDs) as controls. Receiver operating curve analysis was performed to assess their diagnostic accuracy for LM. In patients with NMNDs, CEA and CYFRA 21-1 levels in the CSF were significantly lower than the serum levels. In patients with LM, there was no significant difference between the CSF and serum CEA levels, whereas the CYFRA 21-1 levels were significantly higher in the CSF than the serum. CSF/serum quotients of CYFRA 21-1 were higher than those of CEA in patients with LM and patients with NMNDs. CSF CYFRA 21-1 and CSF/serum quotient of CYFRA 21-1 had high accuracy for differentiating LM from NMNDs that was similar to CSF CEA and CSF/serum quotient of CYFRA 21-1, whereas serum CYFRA 21-1 is of poor diagnostic value. Measurement of CSF CYFRA 21-1 should not be overlooked in patients with suspected LM, even if the serum CYFRA 21-1 level is within normal limits.

Identification of an aptamer through whole cell-SELEX for targeting high metastatic liver cancers

Hepatocellular carcinoma (HCC) is one of the most deadly human cancers due to its ability of invasion and metastasis. Thus, the approaches to identify potential compounds that inhibit invasion and metastasis of HCC are critical for treatment of this disease. In the present study, we used HCCLM9 cells with high metastatic potential and MHCC97L with low metastatic potential as a model system to study the molecular mechanisms of HCC metastasis. By applying cell- Systematic Evolution of Ligands by Exponential enrichment (SELEX) against living cells, we used HCCLM9 as target cells and MHCC97L cells as control to screen a group of HCC metastasis- and cell-specific DNA aptamers. One of selected aptamers, LY-1, could specifically bind to metastatic HCC with a dissociation constant (Kd) in nanomolar range. In vitro studies demonstrated that LY-1 can recognize and bind to membrane protein of metastatic HCC cells. Furthermore, QD605 labeled LY-1 aptamer could recognize HCC cells in both local liver cancer tissues and pulmonary metastatic sites in a xenograft model of HCC with pulmonary metastasis. Further biochemical and immunostaining studies showed that LY-1 could selectively bind to a subpopulation of more metastatic cells in HCCLM9 cells, which express more CK19 and vimentin. Finally, treatment of highly metastatic cells with LY-1 led to reduced migration and invasiveness of HCCLM9 cells in vitro and suppression of xenograft growth in vivo. Taken together, the present study demonstrated the tumor targeting and tumor suppressive effects of LY-1, which could be a promising molecular probe for metastatic HCC and a potential candidate of chemotherapy for metastatic HCC.

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

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.

Keratins: Biomarkers and modulators of apoptotic and necrotic cell death in the liver

Keratins, formerly known as cytokeratins, are the major epithelial-specific subgroup of intermediate filament proteins. Adult hepatocytes express keratin polypeptides 8 and 18 (K8/K18), whereas cholangiocytes express K8/K18 and keratins 7 and 19 (K7/K19). Keratins function primarily to protect hepatocytes from apoptosis and necrosis, which was revealed using several genetic mouse models. This cytoprotective function was further clarified by the identification of natural human keratin variants that are normally silent, but become pathogenic by predisposing their carriers to apoptosis during acute or chronic liver injury mediated by toxins, virus infection, or metabolic stress. During apoptosis, caspases cleave K18 and K19 at conserved aspartates (human K18/K19: (235) Val-Glu-Val-Asp(↓) ) and K18 at a unique aspartate (human K18: (394) Asp-Ala-Leu-Asp(↓) ), with the latter exposed epitope becoming recognized by the M30 antibody in blood and tissues. Additional K18-containing protein backbone epitopes are detected using the M6 and M5 (termed M65) antibodies. Intact K18 and its associated fragments, which are released into blood during apoptosis and necrosis in various diseases, have been analyzed by enzyme-linked immunosorbent assay using the M30/M65 antibodies or their signal ratios. Furthermore, M30/M65 levels have been used as diagnostic and prognostic biomarkers in acute and chronic liver diseases, including nonalcoholic steatohepatitis and acute liver failure. Other keratin biomarkers include K8/K18/K19-related tissue polypeptide antigen, K18-related tissue polypeptide-specific antigen, and K19-related CYFRA-21-1, which have been evaluated mostly in patients with epithelial tumors.

CONCLUSION

Keratins and their fragments are released into blood during liver and other epithelial tissue injury. The epithelial specificity of K18/K19, epitope unmasking upon caspase digestion, keratin abundance, and relative keratin stability render them useful biomarkers for hepatocyte and cholangiocyte apoptosis and necrosis. However, the precise biochemical nature and release mechanism of circulating keratins remain unknown. (Hepatology 2016;64:966-976).

The Progress and Prospects of Putative Biomarkers for Liver Cancer Stem Cells in Hepatocellular Carcinoma

Accumulating evidence suggests that hepatocellular carcinoma (HCC) is organized by liver cancer stem cells (LCSCs), which are a subset of cells with “stem-like” characteristics. Identification of the LCSCs is a fundamental and important problem in HCC research. LCSCs have been investigated by various stem cell biomarkers. There is still lack of consensus regarding the existence of a “global” marker for LCSCs in HCC. In this review article, we summarize the progress and prospects of putative biomarkers for LCSCs in the past decades, which is essential to develop future therapies targeting CSCs and to predict prognosis and curative effect of these therapies.

The application of proteomics in different aspects of hepatocellular carcinoma research

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, which is causing the second leading cancer-related death worldwide. With the significant advances of high-throughput protein analysis techniques, the proteomics offered an extremely useful and versatile analytical platform for biomedical researches. In recent years, different proteomic strategies have been widely applied in the various aspects of HCC studies, ranging from screening the early diagnostic and prognostic biomarkers to in-depth investigating the underlying molecular mechanisms. In this review, we would like to systematically summarize the current applications of proteomics in hepatocellular carcinoma study, and discuss the challenges of applying proteomics in study clinical samples, as well as discuss the possible application of proteomics in precision medicine.

BIOLOGICAL SIGNIFICANCE

In this review, we have systematically summarized the current applications of proteomics in hepatocellular carcinoma study, ranging from screening biomarkers to in-depth investigating the underlying molecular mechanisms. In addition, we have discussed the challenges of applying proteomics in study clinical samples, as well as the possible applications of proteomics in precision medicine. We believe that this review would help readers to be better familiar with the recent progresses of clinical proteomics, especially in the field of hepatocellular carcinoma research.

CK19 and CD99 Immunoexpression Profile in Goblet Cell (Mucin-Producing Neuroendocrine Tumors) and Classical Carcinoids of the Vermiform Appendix

The immunoexpression of CK19 recently has been identified as a marker of poor prognosis in pancreatic endocrine tumors and hepatocellular carcinoma. Conversely, the loss of expression of CD99 has been suggested to play a role in the tumorigenesis and dedifferentiation and is associated with poor outcome in some malignancies. The purpose of this study was to explore CK19 and CD99 immunostaining in mucin-producing neuroendocrine (goblet cell) and classical carcinoids of the appendix. Eighteen goblet cell carcinoids (GCCs) and 20 classic carcinoids were stained with CK19, CD99, and Ki-67, and these results were correlated with known pathological features of aggression: extent of invasion, mitoses, necrosis, and histological pattern. All 18 GCCs were CK19 strongly positive, whereas 16/20 classic carcinoids were also CK19 positive. Fourteen of 18 GCCs and 14/20 classic carcinoids were CD99 positive. CK19/CD99 immunoexpression did not correlate with extent of tumor invasion and mesoappendiceal extension, mitotic activity, Ki-67 labeling index, presence of extracellular mucinous pools dissecting muscle, and angiolymphatic and perineural/neural invasion. There is no difference in the immunostaining for CK19 and CD99 between GCCs and classic carcinoids, and both types of neuroendocrine tumor show the same extent of expression of both markers.

Risk Factors for Distant Metastasis in Patients with Minimally Invasive Follicular Thyroid Carcinoma

Background

Although patients with minimally invasive follicular thyroid carcinoma (MIFTC) generally have an excellent prognosis, distant metastasis occurs in some patients. Risk factors for distant metastasis have been reported, none has been found to be conclusive. This study evaluated risk factors for distant metastasis, including protein markers, in patients with MIFTC.

Methods

A review of patient records identified 259 patients who underwent surgery at Asan Medical Center from 1996 to 2010 and were subsequently diagnosed with MIFTC. After review of pathological slides, 120 patients with paraffin blocks suited for tissue microarrays (TMA) were included in this study. Immunohistochemical stain of TMA slides was performed by protein markers; β-catenin, C-MET, CK19, estrogen receptor (ER) α, ER β, HBME-1, MMP2, PPAR γ and progesterone receptor.

Results

120 patients included 28 males (23.3%) and 92 females (76.7%), of mean age 41.5±10.8 years (range, 13–74 years). Eight patients (6.7%) had distant metastases during follow-up. Univariate analysis showed that age (≥45 years), male sex, and extensive vascular invasion (≥4 foci) were associated with distant metastasis. Multivariate regression analysis showed that extensive vascular invasion was the only independent risk factor for distant metastasis (p = 0.012). Although no protein markers on TMA analysis were directly related to distant metastasis of MIFTC, CK19 expression was more frequent in patients with than without extensive vascular invasion (p = 0.036).

Conclusion

Extensive vascular invasion was the only independent risk factor for distant metastasis of MIFTC. No proteins markers were directly related to distant metastasis, but CK19 was associated with extensive vascular invasion.

The meaning of gross tumor type in the aspects of cytokeratin 19 expression and resection margin in patients with hepatocellular carcinoma

BACKGROUND

There is no consensus on the safe resection margin in patients with hepatocellular carcinoma. Surgeons decide the extent of resection according to residual liver function and tumor location. We investigated the influence of resection margin on early recurrence with respect to gross tumor type and expression of cytokeratin 19 (CK19).

METHODS

We divided the patients into two groups based on the classification of The Korean Liver Cancer Study group as follows: group 1 included expanding and vaguely nodular types whereas group 2 included nodular with perinodular extension, multinodular confluent, and infiltrative types. We classified the resection margin as narrow (0.1-0.9 cm) or wide (greater than 1 cm). We compared clinicopathological features and CK19 positivity between the groups.

RESULTS

Group 2 had a higher prevalence of gross portal vein invasion, microscopic portal vein invasion, microvessel invasion, satellite nodules, intrahepatic metastasis, multicentric occurrence, and positivity for CK19. Group 1 showed no difference in recurrence according to the resection margin; however, group 2 showed a higher recurrence rate in patients with a narrow resection margin compared with those with a wide resection margin (P = 0.047). Patients in group 2 with CK19 positivity showed a higher prevalence of microvessel invasion than those without CK19 (P = 0.026).

CONCLUSIONS

Although our study has the limitation of a small number of cases, the data suggest that patients with hepatocellular carcinoma of expanding and vaguely nodular gross types may safely undergo surgical resection with a narrow resection margin and a low risk of early recurrence.

Use of Cytokeratin-19 Concentration to Assess Early Recurrence and Prognosis of Hepatitis B Virus-Related Hepatocellular Carcinoma following Radical Resection in Patients with a Low Serum Alpha-Fetoprotein Concentration

Cytokeratin 19 (CK-19) is a prognostic indicator of recurrence and metastasis of hepatocellular carcinoma (HCC) following radical resection. To investigate the role of CK-19 in assessment of early recurrence and prognosis in patients with hepatitis B virus (HBV)-related HCC following radical resection. In total, 235 patients with HBV-related HCC (age, 15-82 years; mean age, 54 ± 10 years) undergoing radical resection were screened for inclusion from January 2005 to December 2010. Malignant tissues and adjacent non-malignant tissues were sampled during surgery, and CK-19 and Ki-67 expression was determined by tissue microarray and immunohistochemistry. CK-19 mRNA levels in 30 randomly selected frozen HCC specimens were examined by reverse transcription polymerase chain reaction from January 2011 to June 2011. Correlations of CK-19 and Ki-67 expression with tumor recurrence, metastasis, disease-free survival (DFS), and overall survival (OS) were analyzed. Elevated CK-19 expression was correlated with early recurrence (P = 0.001), shorter DFS (P = 0.001), and reduced OS (P = 0.010). CK-19 expression was correlated with the Ki-67 index (P = 0.037), histological differentiation (P = 0.016), focal number (P = 0.044), and blood vessel tumor embolism (P = 0.002). Patients with metastasis within 1 year exhibited stronger CK-19 expression than did patients without metastasis (P < 0.05). Furthermore, early recurrence was associated with elevated CK-19 mRNA levels (χ2 = 5.761, P = 0.016).When confirmed by a low alpha-fetoprotein concentration (<400 μg/L), CK-19 expression in surgical biopsy specimens taken from patients with HCC during radical resection is an additional valuable indicator of early recurrence, distant metastasis, and poor prognosis in HBV-positive patients.

Capture and Release of Cancer Cells by Combining On-Chip Purification and Off-Chip Enzymatic Treatment

As "liquid biopsies", circulating tumor cells (CTCs) have been thought to hold significant insights for cancer diagnosis and treatment. Despite the advances of microfluidic techniques that improve the capture of CTCs to a certain extent, recovering the captured CTCs with enhanced purity at the same time remains a challenge. Here, by combining on-chip purification and off-chip enzymatic treatment, we demonstrate a two-stage strategy to enhance the purity of captured cancer cells from blood samples. The on-chip purification introduces a stirring flow to increase the capture sensitivity and decrease nonspecifically bounded cells. The off-chip enzymatic treatment enables the cancer cells to be released from the attached magnetic beads, further improving the purity and enabling next reculture. For the proof-of-concept study, spiked cancer cells are successfully obtained from unprocessed whole blood with high recovery rate (∼68%) and purity (∼61%), facilitating subsequent RNA expression analysis.

ITMSQ: A software tool for N- and C-terminal fragment ion pairs based isobaric tandem mass spectrometry quantification

Tandem MS (MS2) quantification using the series of N- and C-terminal fragment ion pairs generated from isobaric-labelled peptides was recently considered an accurate strategy in quantitative proteomics. However, the presence of multiplexed terminal fragment ion in MS2 spectra may reduce the efficiency of peptide identification, resulting in lower identification scores or even incorrect assignments. To address this issue, we developed a quantitative software tool, denoted isobaric tandem MS quantification (ITMSQ), to improve N- and C-terminal fragment ion pairs based isobaric MS2 quantification. A spectrum splitting module was designed to separate the MS2 spectra from different samples, increasing the accuracy of both identification and quantification. ITMSQ offers a convenient interface through which parameters can be changed along with the labelling method, and the result files and all of the intermediate files can be exported. We performed an analysis of in vivo terminal amino acid labelling labelled HeLa samples and found that the numbers of quantified proteins and peptides increased by 13.64 and 27.52% after spectrum splitting, respectively. In conclusion, ITMSQ provides an accurate and reliable quantitative solution for N- and C-terminal fragment ion pairs based isobaric MS2 quantitative methods.

Expression of cancer stem cell biomarkers as a tool for a correct therapeutic approach to hepatocellular carcinoma

Liver cancer is the fifth most commonly diagnosed malignancy and the second most frequent cause of cancer death in men worldwide. Amongst liver cancers, hepatocellular carcinoma (HCC) represents the major histological subtype and it is one of the most common malignant human tumors worldwide. Research into the molecular biology of hepatocarcinogenesis has identified several biomarkers, which could provide additional informations in order to better understand the biology of HCC. A large number of biomarkers have been shown to have potential predictive significance and a wide variety of molecular markers have been proven to be excellent diagnostic tools for HCC but it is difficult to characterize HCC with a single biomarker. Thus, signatures of a combination of biomarkers may be more valuable for the diagnosis, staging and prognosis of HCC. Specifically, a correlation of HCC-CSCs phenotype to specific hepatic cancer subtypes and to specific clinical and pathological features has not yet been reported in human liver tumors. In this view we will first discuss the possible sources of liver stem cells and their relation with liver cancer development and we will secondly focus on the prognostic significance of clinical and pathological features of HCC.

MRI features of hepatocellular carcinoma related to biologic behavior

Imaging studies including magnetic resonance imaging (MRI) play a crucial role in the diagnosis and staging of hepatocellular carcinoma (HCC). Several recent studies reveal a large number of MRI features related to the prognosis of HCC. In this review, we discuss various MRI features of HCC and their implications for the diagnosis and prognosis as imaging biomarkers. As a whole, the favorable MRI findings of HCC are small size, encapsulation, intralesional fat, high apparent diffusion coefficient (ADC) value, and smooth margins or hyperintensity on the hepatobiliary phase of gadoxetic acid-enhanced MRI. Unfavorable findings include large size, multifocality, low ADC value, non-smooth margins or hypointensity on hepatobiliary phase images. MRI findings are potential imaging biomarkers in patients with HCC.

Pathogenesis and prognosis of hepatocellular carcinoma at the cellular and molecular levels

Different approaches predict the outcome for patients with hepatocellular carcinoma (HCC). The expression of biliary-hepatic progenitor cell markers generally correlates with poor prognosis. This article focuses on the pathogenesis of HCC, how differentiation or dedifferentiation leads to a phenotype switch, and heterogeneity in the same tumor. A tumor cell decides its fate based on a complex interplay of signaling pathways. Interaction with the microenvironment decides whether it will invade, proliferate, or enter survival mode. Several signaling pathways contribute to stemness features, reflecting a small chemoresistant subpopulation of the tumor that expresses biliary-hepatic progenitor cell markers.

Serum CYFRA 21-1 in Biliary Tract Cancers: A Reliable Biomarker for Gallbladder Carcinoma and Intrahepatic Cholangiocarcinoma

BACKGROUND

Biliary tract cancers encompass gallbladder carcinoma, and intrahepatic, perihilar and distal cholangiocarcinoma. Upregulated serum CYFRA 21-1 has been reported in intrahepatic cholangiocarcinoma.

AIMS

The present study aimed to explore the clinical significance of serum CYFRA 21-1 in all biliary tract cancer subtypes.

METHODS

Serum CYFRA 21-1, carbohydrate antigen 19-9 and carcinoembryonic antigen were quantitated preoperatively, postoperatively and during follow-up in 134 malignant and 52 benign patients. Receiver operator characteristic curves of biomarkers were analyzed. Level of CYFRA 21-1 was correlated with patients' clinicopathological features and follow-up data.

RESULTS

CYFRA 21-1 was significantly upregulated in biliary malignancies, and expressional difference existed between these subtypes. Based on the maximal Youden's index, cutoff values were selected (ng/mL): 2.61 for biliary tract cancers (sensitivity 74.6 % and specificity 84.6 %); 3.27 for intrahepatic cholangiocarcinoma (75.6 and 96.2 %) and gallbladder carcinoma (93.7 and 96.2 %); 2.27 for perihilar cholangiocarcinoma (71.0 and 71.2 %); and 2.61 for distal cholangiocarcinoma (63.3 and 84.6 %). CYFRA 21-1 showed better diagnostic performance than other biomarkers in gallbladder carcinoma and intrahepatic cholangiocarcinoma; its performance was not inferior to that of the combination of these three biomarkers and declined after curative resection and re-elevated when tumor recurred, which was correlated with tumor aggressiveness and TNM stage; it was an independent predictor for 1-year recurrence-free survival and overall survival on multivariate analysis.

CONCLUSION

Serum CYFRA 21-1 represents a reliable biomarker for gallbladder carcinoma and intrahepatic cholangiocarcinoma.

CK19 is a sensitive marker for yolk sac tumours of the testis

Background

Malignant germ cell tumours are the most common malignant tumours in young men. They are histologically divided into seminomas and non-seminomas. Non-seminomas are further subdivided into embryonic carcinomas, yolk sac tumours, chorionic carcinomas, and teratomas. For the therapeutic management it is essential to differentiate between these histological subtypes.

Methods

Investigated cases included normal testis (n = 50), intratubular germ cell neoplasia (n = 25), seminomas (n = 67), embryonic carcinomas (n = 56), yolk sac tumours (n = 29), chorionic carcinomas (n = 2), teratomas (n = 7) and four metastases of YST’s for their CK19 expression. In addition Leydig cell- (n = 10) and Sertoli cell- tumours (n = 4) were included in this study.

Results

All investigated seminomas, embryonic carcinomas as well as normal testis and intratubular germ cell neoplasias did not express CK19. In contrast, all investigated yolk sac tumours strongly expressed CK19 protein. These findings became also evident in mixed germ cell tumours consisting of embryonic carcinomas and yolk sac tumours, although CK19-expression could also be observed in analysed chorionic carcinomas and epithelial components of teratomas.

Conclusion

CK19 proved to be a sensitive marker to identify yolk sac tumours of the testis and to distinguish them from other germ cell tumours, especially seminomas and embryonic carcinomas.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4075546891400979.

Time-dependent effect of hypoxia on tumor progression and liver progenitor cell markers in primary liver tumors

BACKGROUND & AIMS

Expression of liver progenitor cell (LPC) characteristics has been proposed as a negative prognostic marker in primary liver tumors. Hypoxia has been linked to activation of the Notch pathway which is responsible for activation and proliferation of LPCs and hypoxia-induced LPC activation has been shown in hepatocellular carcinoma. Our aim was to elucidate the time-dependent effects of hypoxia on the LPC niche in hepatocellular carcinoma which could aid in determining a safe time frame for use of hypoxia inducing therapies.

METHODS

We used dimethyloxaloylglycine to mimic a hypoxic reaction in mice by stabilizing hypoxia-inducible factor 1 alpha at three distinct time points in diethylnitrosamine induced hepatocarcinogenesis. LPC, metastasis and Notch pathway markers were determined by quantitative PCR and (immune)histochemistry (heamatoxillin-eosin, reticulin, Sirius red and cytokeratin 19 staining).

RESULTS

Activating the hypoxia inducible pathway early in hepatocarcinogenesis resulted in an increased incidence of both cholangioma and hepatocellular lesions, associated with high expression of LPC, metastatic and Notch pathway markers. Adversely, activating the hypoxic response during tumor development resulted in decreased incidence of hepatocellular lesions and increased cholangioma incidence, with an unaltered gene expression profile of LPC-, Notch pathway- and metastatic markers. A hypoxic insult at advanced stages of hepatocarcinogenesis severely increased the expression of LPC characteristics, however without increased expression of actors of the Notch pathway and metastatic markers and minor changes in incidence of hepatocellular and cholangioma lesions.

CONCLUSION

Our results indicate that increased hypoxia at the onset of tumor development has detrimental effects on tumor progression; patients with HCC developed in a background of fibrosis/cirrhosis might therefore represent a more difficult treatment group. In contrast, hypoxia during tumor development appears to favor tumor outcome, highlighting the importance of early detection. Finally, hypoxia in advanced stages resulted in increased expression of LPC characteristics indicating poor outcome.

Hepatocellular carcinomas expressing 'stemness'-related markers: clinicopathological characteristics

Hepatocellular carcinoma (HCC) is heterogeneous in histopathology, pathogenesis and biological behavior. There is accumulating evidence that the expression of 'stemness'-related markers such as K19, EpCAM and CD133 in HCC is associated with an aggressive biological behavior and poor clinical outcome compared to conventional HCCs that do not express stemness-related markers. Compared to conventional HCCs, these tumors more frequently demonstrate infiltrative growth patterns, vascular invasion and more intratumoral fibrous stroma, and there is a spectrum of morphological and immunophenotypic features between HCCs with stemness-related marker expression, scirrhous HCCs and combined hepatocellular-cholangiocarcinoma with stem cell features. Clinically, HCCs with stemness-related marker expression are associated with increased serum α-fetoprotein levels and a poor prognosis, and are also beginning to be noticed radiologically. These tumors have also been recognized as a specific subtype in recent molecular classifications, and increasing interest in the molecular pathogenesis of HCCs with stemness-related marker expression will shed light on the development of targeted therapy for these tumors. Therefore, it is important that pathologists identify HCCs expressing stemness-related markers such as K19 during routine pathological evaluation of surgically resected or biopsied HCC tissue, as it will help to identify a high-risk subgroup of HCCs characterized by increased chemoresistance, earlier recurrence after surgical and/or locoregional treatment, increased invasiveness/metastasis and poor overall survival. We will discuss the clinicopathological characteristics of a HCC subtype expressing stemness-related markers and its future perspectives.

Expression of bile duct transcription factor HNF1β predicts early tumor recurrence and is a stage-independent prognostic factor in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) frequently exhibits biliary differentiation, which is typically overlooked. Hepatocyte nuclear factor 1β (HNF1β), a bile duct-specific transcription factor expressed in bile ducts but not in the normal hepatocytes, is also expressed in HCC.

MATERIALS AND METHODS

The expression of HNF1β and the biliary differentiation marker cytokeratin 19 (CK19) were retrospectively evaluated using immunohistochemistry in 159 surgically resected primary HCCs.

RESULTS

A significant correlation was observed between HNF1β protein expression and younger age (p = 0.0293), high serum α-fetoprotein levels (p = 6 × 10(-4)), and high tumor grade (p = 0.0255). However, HNF1β expression exhibited no correlation with tumor stage. Patients with HCCs and HNF1β expression were more likely to exhibit early tumor recurrence (ETR; p = 0.0048) and a lower 5-year survival rate (p = 0.0001). A multivariate analysis indicated HNF1β expression as an independent prognostic factor in HCC (p = 0.0048). A combinatorial analysis revealed additive adverse effects of HNF1β when concomitant with CK19 expression and p53 mutation. Furthermore, HNF1β expression can predict poor prognosis in patients with ETR.

CONCLUSION

Our results indicated that HNF1β expression is a crucial predictor of poor prognosis in HCC and is independent of tumor stage. Moreover, concomitant HNF1β and CK19 expressions exhibited additive adverse effects in HCC, confirming that HCC with biliary differentiation has a poor prognosis.

Changes in glucose-6-phosphate dehydrogenase expression results in altered behavior of HBV-associated liver cancer cells

Hepatocellular carcinoma (HCC) is regarded as a major global health care issue, and chronic hepatitis B virus (HBV) infection is considered to be involved in pathogenesis of HCC. To increase knowledge of HCC pathogenesis, as well as discover potential novel molecules for anti-cancer therapy, mass spectrometry and isobaric tag for relative and absolute quantitation (iTARQ) were employed. The differences between nine HBV-related HCC and adjacent non-HCC tissue specimens were studied. In total, 222 proteins were analyzed for differential expression in the two types of samples. Among these proteins, several were further confirmed by immunohistochemical, immunoblotting, and real-time RT-PCR analysis. RNA interference induced downregulation of glucose-6-phosphate dehydrogenase (G6PD) and decreased HBV replication by fivefold by the IFN pathway. Decreased G6PD expression resulted in decreased hepatoma cell migration and invasion in cell culture. In summary, the investigation provides new information on pathogenesis of HBV infection and suggests G6PD as a novel anti-HCC target. G6PD suppression may contribute to treatment strategies for inhibiting tumor progression.

Nucleolin identified by comparative mass‑spectra analysis is a potential marker for invasive progression of hepatocellular carcinoma

At present, the diagnosis and prognosis of hepatocellular carcinoma (HCC) metastasis remains poor. Recently, a number of proteins associated with the metastasis and invasion of HCC were identified; however, the effective markers require further elucidation. In the current study, a nucleolin expression was observed in MHCC97L and HCCLM9 HCC cell lines, with low and high metastatic potentials respectively, using comparative proteomics. The data indicated that nucleolin expression in the nucleus was significantly higher in HCCLM9 cells, and it primarily influenced the migration of HCC cells in vitro. Thus, to the best of our knowledge this is the first study to hypothesize that nucleolin may be a novel marker for HCC invasive progression.

Cytokeratin 7/19 expression in N-diethylnitrosamine-induced mouse hepatocellular lesions: implications for histogenesis

Hepatocellular carcinoma (HCC) is a common malignancy with poor clinical outcome, whose histogenesis is the subject of intense debate. Specifically, expression of cytokeratins (CKs) 7 and 19, associated with aggressive biological behaviour, is proposed to reflect a possible progenitor cell origin or tumour dedifferentiation towards a primitive phenotype. This work addresses that problem by studying CKs 7 and 19 expression in N-diethylnitrosamine (DEN)-induced mouse HCCs. ICR mice were divided into six DEN-exposed and six matched control groups. Samples were taken from each group at consecutive time points. Hyperplastic foci (13 lesions) occurred at 29-40 weeks (groups 8, 10 and 12) with diffuse dysplastic areas (19 lesions) and with one hepatocellular adenoma (HCA) (at 29 weeks). HCCs (4 lesions) were observed 40 weeks after the first DEN administration (group 12). CKs 7 and 19 showed identical expression patterns and located to large, mature hepatocytes, isolated or in small clusters. Hyperplastic foci and the single HCA were consistently negative for both markers, while dysplastic areas and HCCs were positive. These results support the hypothesis that CKs 7 and 19 expression in hepatocellular malignancies results from a dedifferentiation process rather than from a possible progenitor cell origin.

Functional proteomic analysis reveals the involvement of KIAA1199 in breast cancer growth, motility and invasiveness

Background

KIAA1199 is a recently identified novel gene that is up-regulated in human cancer with poor survival. Our proteomic study on signaling polarity in chemotactic cells revealed KIAA1199 as a novel protein target that may be involved in cellular chemotaxis and motility. In the present study, we examined the functional significance of KIAA1199 expression in breast cancer growth, motility and invasiveness.

Methods

We validated the previous microarray observation by tissue microarray immunohistochemistry using a TMA slide containing 12 breast tumor tissue cores and 12 corresponding normal tissues. We performed the shRNA-mediated knockdown of KIAA1199 in MDA-MB-231 and HS578T cells to study the role of this protein in cell proliferation, migration and apoptosis in vitro. We studied the effects of KIAA1199 knockdown in vivo in two groups of mice (n = 5). We carried out the SILAC LC-MS/MS based proteomic studies on the involvement of KIAA1199 in breast cancer.

Results

KIAA1199 mRNA and protein was significantly overexpressed in breast tumor specimens and cell lines as compared with non-neoplastic breast tissues from large-scale microarray and studies of breast cancer cell lines and tumors. To gain deeper insights into the novel role of KIAA1199 in breast cancer, we modulated KIAA1199 expression using shRNA-mediated knockdown in two breast cancer cell lines (MDA-MB-231 and HS578T), expressing higher levels of KIAA1199. The KIAA1199 knockdown cells showed reduced motility and cell proliferation in vitro. Moreover, when the knockdown cells were injected into the mammary fat pads of female athymic nude mice, there was a significant decrease in tumor incidence and growth. In addition, quantitative proteomic analysis revealed that knockdown of KIAA1199 in breast cancer (MDA-MB-231) cells affected a broad range of cellular functions including apoptosis, metabolism and cell motility.

Conclusions

Our findings indicate that KIAA1199 may play an important role in breast tumor growth and invasiveness, and that it may represent a novel target for biomarker development and a novel therapeutic target for breast cancer.

Proteome Analyses of Hepatocellular Carcinoma

Proteomics has evolved into a powerful and widely used bioanalytical technique in the study of cancer, especially hepatocellular carcinoma (HCC). In this review, we provide an up to date overview of feasible proteome-analytical techniques for clinical questions. In addition, we present a broad summary of proteomic studies of HCC utilizing various technical approaches for the analysis of samples derived from diverse sources like HCC cell lines, animal models, human tissue and body fluids.

Overexpression of RhoGDI, a novel predictor of distant metastasis, promotes cell proliferation and migration in hepatocellular carcinoma

RhoGDI (Rho GDP-dissociation inhibitor alpha, or RhoGDIα) was identified as a regulator of Rho GTPases, but its role in cancer remains controversial. In this study, increased expression of RhoGDI was detected in hepatocellular carcinoma (HCC) cell lines and tissues with highly metastatic potential. RhoGDI overexpression correlated with postoperative distant metastasis. Enforced expression of RhoGDI in HCC cells significantly enhanced cell proliferation and migration. Conversely, knockdown of RhoGDI caused an inhibition of the aggressive phenotypes of HCC cells. Furthermore, RhoGDI up-regulated Rho, but not Rac, and enhanced PI3K/AKT and MAPK pathway activity. Our findings suggest that RhoGDI overexpression is a predictor of distant metastasis and plays an important role in the progression of HCC.