CD133: a potential indicator for differentiation and prognosis of human cholangiocarcinoma

m6A demethylase ALKBH5 maintains stemness of intrahepatic cholangiocarcinoma by sustaining BUB1B expression and cell proliferation

ALKBH5 plays critical roles in various cellular processes via post-transcriptional regulation of oncogenes or tumor suppressors in an N6-methyladenosine (m6A)-dependent manner. However, its function in intrahepatic cholangiocarcinoma (ICC) remains unclear. In the present study, bioinformatic analyses of The Cancer Genome Atlas (TCGA) data were performed, and the association of ALKBH5 in predicting overall survival in patients with ICC was investigated. Then, the clinical data of patients from The Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University (Changzhou, China) was used to reveal the overall survival of patients with ICC with different ALKBH5 expression levels by Kaplan-Meier survival analysis. Subsequently, in vitro and in vivo studies were conducted to explore and verify the downstream genes regulated by ALKBH5. The results from TCGA data demonstrated that ALKBH5 expression is elevated in ICC and that patients with high ALKBH5 expression exhibited poor survival compared with patients with low expression. In addition, in vitro assays demonstrated that ALKBH5 promoted cell viability and maintained the stemness of ICC cells, leading to ICC progression. The present study also demonstrated that BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) is the downstream gene regulated by ALKBH5 and targeting BUB1B suppressed cell growth. The in vitro and vivo experiments revealed that ALKBH5 might function through BUB1B to maintain the stemness of ICC and that altering BUB1B may suppress ICC progression.

Differential expression of hepatic cancer stemness and hypoxia markers in residual cancer after locoregional therapies for hepatocellular carcinoma

Transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) treatment to hepatocellular carcinoma (HCC) are effective tools to control tumor growth, prolong survival, palliate symptoms, and improve quality of life for patients with intermediate-stage HCC. Nevertheless, there is high variability of local HCC responses to locoregional therapies; therefore, better and personalized prediction of tumor response to TACE is necessary for management of patients with HCC, especially when these modalities of treatment are used to bridge patients for liver transplant. Here, we investigated differential expression of hepatic cancer stem cell and hypoxia in residual HCC after TACE treatment in comparison with TARE. A publicly available gene data set was screened for differentially expressed genes (DEGs) in TACE_Response compared with TACE_Non-response HCC. Analysis of the GSE104580 data set displayed a total of 406 DEGs, including 196 down-regulated and 210 up-regulated DEGs. Of the 196 down-regulated DEGs, three hepatic cancer stem cell (CSC) markers and 11 hypoxia-related genes were identified. Immunohistochemical staining of hepatic CSC and hypoxia markers on explant liver tissues exhibited more intense positive staining of hepatic CSC markers (CD24, EpCAM) and hypoxia marker carbonic anhydrase 9 (CA9) in residual tumor nodule from patients with HCC treated with TACE compared with nontreated patients. Furthermore, Pearson's correlation analysis revealed the significant correlation between hepatic CSC markers and hypoxia marker, CA9. Conclusion: Hepatic CSC and hypoxia markers predict nonresponse to TACE and are differentially expressed in residual tumor after TACE compared with TARE. In the long term, TACE-induced hypoxia may select an aggressive HCC phenotype.

Clinical relevance of biomarkers in cholangiocarcinoma: critical revision and future directions

Cholangiocarcinoma (CCA) is a malignant tumour arising from the biliary system. In Europe, this tumour frequently presents as a sporadic cancer in patients without defined risk factors and is usually diagnosed at advanced stages with a consequent poor prognosis. Therefore, the identification of biomarkers represents an utmost need for patients with CCA. Numerous studies proposed a wide spectrum of biomarkers at tissue and molecular levels. With the present paper, a multidisciplinary group of experts within the European Network for the Study of Cholangiocarcinoma discusses the clinical role of tissue biomarkers and provides a selection based on their current relevance and potential applications in the framework of CCA. Recent advances are proposed by dividing biomarkers based on their potential role in diagnosis, prognosis and therapy response. Limitations of current biomarkers are also identified, together with specific promising areas (ie, artificial intelligence, patient-derived organoids, targeted therapy) where research should be focused to develop future biomarkers.

Clinical implications of cancer stem cells in digestive cancers: acquisition of stemness and prognostic impact

Digestive system cancers are the most frequent cancers worldwide and often associated with poor prognosis because of their invasive and metastatic characteristics. Recent studies have found that the plasticity of cancer cells can impart cancer stem-like properties via the epithelial-mesenchymal transition (EMT). Cancer stem-like properties such as tumor initiation are integral to the formation of metastasis, which is the main cause of poor prognosis. Numerous markers of cancer stem cells (CSCs) have been identified in many types of cancer. Therefore, CSCs, via their stem cell-like functions, may play an important role in prognosis after surgery. While several reports have described prognostic analysis using CSC markers, few reviews have summarized CSCs and their association with prognosis. Herein, we review the prognostic potential of eight CSC markers, CD133, CD44, CD90, ALDH1A1, EPCAM, SOX2, SOX9, and LGR5, in digestive cancers including those of the pancreas, colon, liver, gastric, and esophagus.

Role of Cancer Stem Cells in Cholangiocarcinoma and Therapeutic Implications

Cholangiocarcinoma (CCA) is the second most common type of liver cancer, and is highly aggressive with very poor prognosis. CCA is classified into intrahepatic cholangiocarcinoma (iCCA) and extra-hepatic cholangiocarcinoma (eCCA), which is further stratified into perihilar (pCCA) and distal (dCCA). Cancer stem cells (CSCs) are a subpopulation of cancer cells capable of tumor initiation and malignant growth, and are also responsible for chemoresistance. Thus, CSCs play an important role in CCA carcinogenesis. Surface markers such as CD133, CD24, CD44, EpCAM, Sox2, CD49f, and CD117 are important for identifying and isolating CCA CSCs. CSCs are present in the tumor microenvironment (TME), termed ‘CSC niche’, where cellular components and soluble factors interact to promote tumor initiation. Epithelial-to-mesenchymal transition (EMT) is another important mechanism underlying carcinogenesis, involved in the invasiveness, metastasis and chemoresistance of cancer. It has been demonstrated that EMT plays a critical role in generating CSCs. Therapies targeting the surface markers and signaling pathways of CCA CSCs, proteins involved in TME, and immune checkpoint proteins are currently under investigation. Therefore, this review focuses on recent studies on the roles of CSCs in CCA; the possible therapeutic strategies targeting CSCs of CCA are also discussed.

Cancer stem cells and fibroblast niche cross talk in an in-vitro oral dysplasia model

Understanding the cellular interactions during oral carcinogenesis has the potential to identify novel prognostic and therapeutic targets. This study aimed at investigating the cancer stem cell (CSC)-fibroblast niche interactions using in-vitro dysplastic cell line models developed from different stages of 4NQO-induced oral carcinogenic mice model. The spontaneously transformed epithelial cells (DysMSCTR6, 14 and 16) were developed from three time points (mild/moderate/severe), while two fibroblast cell lines (FibroMSCTR12, 16) were developed from moderate and severe dysplastic tissue. The epithelial (Epcam+/Ck+) and the fibroblast cell lines (Vimentin+/α-SMA+/Ck-) were authenticated and assessment of cells representing progressive grades of dysplastic severity indicated a significant increase in dysplastic marker profile (P < 0.05). Evaluation of the CSC characteristics showed that an increase in expression of Cd133, Cd44, Aldh1a1, Notch1, and Sox2 was accompanied by an increase in migratory (P > 0.05) and colony formation capacity (P > 0.005). Targeting Notch1 (GSI inhibitor PZ0187; 30 μM), showed a significant reduction in cell proliferation capacity (P < 0.05) and in the dysplastic marker profile. Further, Notch1 inhibition resulted in down regulation of Cd133 and Aldh1a 1 (P < 0.05) and a complete abrogation of colony formation ability (P < 0.0001). The effect of niche interactions evaluated using FibroMSCTR12-conditioned media studies, revealed an enrichment of ALDH1A1+ cells (P < 0.05), induction of spheroid formation ability (P < 0.0001) and increased proliferation capacity (3.7 fold; P < 0.005). Although PZ0187 reduced cell viability by ∼40%, was unable to abrogate the conditioned-media induced increase in proliferation capacity completely. This study reports a Notch-1 dependent enrichment of CSC properties during dysplastic progression and a Notch-1 independent dysplastic cell-fibroblast interaction during oral carcinogenesis.

Cytoplasmic CD133 expression correlates with histologic differentiation and is a significant prognostic factor in extrahepatic bile duct cancer and gallbladder cancer

Prominin-1 (CD133) is one of the most important stem cell markers among various malignant tumor types, but the clinicopathological significance of CD133 expression in intrahepatic cholangiocarcinoma remains controversial. To the best of our knowledge, there have been no reports on extrahepatic bile duct cancer (EHBDCA) and gallbladder cancer (GBCA). The present study examined the clinicopathological significance of CD133 expression in EHBDCA and GBCA. Immunohistochemistry was used to evaluate CD133 expression in resected specimens obtained from 82 patients with EHBDCA and GBCA, and this expression was compared with the clinicopathological parameters and survival data of the patients. Cytoplasmic CD133 expression was identified in 20 patients, and its incidence was significantly associated with histopathological grade (P=0.035), pT factor (P=0.020) and recurrence (P=0.046). Survival analysis revealed that cytoplasmic CD133 expression in patients was significantly associated with a poorer overall survival (OS) and relapse-free survival (RFS) compared with those without cytoplasmic expression (5-year OS rate, 11.6% vs. 39.1%; 3-year RFS rate, 12.5% vs. 42.0%, respectively). Multivariate analysis revealed that cytoplasmic CD133 expression was an independent prognostic factor for OS and RFS (P=0.0036 and P<0.0001, respectively). To the best of our knowledge, this is the first report demonstrating that cytoplasmic CD133 expression was associated with histologic differentiation, cancer progression, recurrence and poor prognosis in EHBDCA and GBCA. CD133 expression may be a useful marker for clinical prognosis in patients with EHBDCA and GBCA.

CD133 Expression as a Helicobacter pylori-independent Biomarker of Gastric Cancer Progression

BACKGROUND/AIM

Gastric adenocarcinoma is the fourth most common cancer worldwide. While gastric cancer prevalence varies globally and incidence rates are decreasing in the West, many cases continue to be diagnosed at an advanced stage and the 5-year survival rate still falls below 30%. Early treatment of gastric cancer by endoscopic and/or surgical therapy may decrease mortality; yet reliable, universally applicable biomarkers for early detection of gastric cancer have still not been established.

MATERIALS AND METHODS

The present work compares the expression of CD133 (prominin-1), a potential biomarker of disease progression in gastric cancer, between independent cohorts of H. pylori (+) and H. pylori (-) patients at each respective stage of carcinogenesis. H. pylori (-) patients (N=45) who underwent gastric biopsy at the Moffitt Cancer Center (MCC) in Tampa, Florida, and H. pylori (+) patients (N=59) who underwent gastric biopsy at the Instituto de Patologia Mejia Jimenez (IPMJ) in Cali, Colombia were evaluated and immunostained for CD133.

RESULTS

A statistically significant increase in CD133 expression (in terms of the Allred score) was observed between all stages of progression (normal mucosa, inflammation/metaplasia, low-grade dysplasia and gastric adenocarcinoma) for each respective patient cohort. No statistically significant difference in CD133 expression at each respective stage of disease was observed between the H. pylori-positive and negative-cohorts.

CONCLUSION

The observation of distinct stepwise increases in CD133 expression in both patient cohorts, and the lack of any significant difference between groups, suggests that CD133 expression may serve as a biomarker for early detection of gastric cancer independent of bacterial status and strain, and corresponding differences in disease histomorphology and classification. This warrants further validation on larger independent cohorts across multiple geographic regions and incorporating multiple bacterial strain types.

CD133 expression in cancer cells predicts poor prognosis of non-mucin producing intrahepatic cholangiocarcinoma

BACKGROUND

CD133 is a marker of stem cells as well cancer stem cells. This study investigated the association between CD133 expression in cancer cells and the clinical outcome of non-mucin producing intrahepatic cholangiocarcinoma (ICC).

METHODS

Fifty-seven non-mucin producing ICC patients were enrolled in this study. Immunohistochemistry (IHC) and immunofluorescence staining for CD133 as well as other cancer-associated proteins, including cytokeratin 19, TGF-β1, p-Smad2 and epithelial-mesenchymal transition (EMT) markers S100A4, E-Cadherin and Vimentin were analyzed.

RESULTS

IHC staining showed that tumor cells in 52.6% of patients expressed CD133. The CD133+ patients had significantly higher metastasis rate than those without CD133+ tumor cells (36.7% vs. 10.1%, p = 0.03). The CD133+ patients had shorter overall and disease-free survival time as compared to the CD133- patients. Furthermore, 90.9% of CD133+ patients developed cancer recurrence, as compared to 64.3% of CD133- patients (p = 0.02). As compared to CD133- patients, tumor cells in CD133+ patients demonstrated high levels of TGF-β/p-Smad2 as well as EMT-like alteration, characterized by loss of E-Cadherin and expression of Vimentin and S100A4.

CONCLUSIONS

CD133 expression in ICC tumor cells indicates poor prognosis of the disease and might be associated with TGF-β related EMT alterations.

Prognostic value of the expression of cancer stem cell-related markers CD133 and CD44 in hepatocellular carcinoma: From patients to patient-derived tumor xenograft models

High expression of cancer stem cell (CSC) markers is related to poor prognosis of patients with hepatocellular carcinoma (HCC). However, the expression of these markers in patient-derived xenograft (PDX) models and the relationship of the expression levels of these markers between HCC patients and their PDX models at subsequent low passages are unclear. To investigate the prognostic impact of putative CSC markers in patients with HCC and in related PDX models, the expression of CD133, CD90, CD44, ALDH1, CK7, CK19, OCT4, SOX2, vimentin, nestin, CD13 and EpCam were assessed by quantitative reverse transcription-PCR (qRT-PCR) and then were validated using immunohistochemistry in tumor or peritumoral tissues from patients and tumor tissues from PDX models. Cumulative survival analysis of the patients and animals was conducted using the Kaplan-Meier method and the log-rank test. Only the expression levels of CD133 and CD44 were higher in tumor tissues than in the peritumoral tissues of HCC patients by qRT-PCR. High consistency of the prognostic value of the expression of CD133/CD44 was observed in HCC patients and the PDX models. High expression levels of CD133 and CD44 were positively related to the poor prognosis of HCC patients and to that in the PDX models. PDX HCC models in the present study have been suggested to be predictive of disease outcome, which could shed light on personalized medicine and the mechanisms of CSC marker expression on prognosis.

Predictive value for lymph node metastasis of epithelial-mesenchymal transition and cancer stem cell marker expression in early gastric cancer

BACKGROUND

Minimally invasive therapies, including endoscopic mucosal resection or sentinel node navigation surgery, have been widely applied in early gastric cancer because of their benefits in promoting patient quality of life. However, lymph node dissection is beyond the capability of endoscopic therapy, and in sentinel node navigation surgery, the potential for skip metastasis is not negligible. Therefore, the possibility of lymph node metastasis is the most important factor to consider when deciding whether to apply the minimally invasive therapies. In the present study, the significance of epithelial mesenchymal transition and stem cell marker expression in lymph node metastasis in early gastric cancer was investigated.

METHODS

We evaluated the significance of the expression of 5 epithelial mesenchymal transition-related markers (E-cadherin, MMP7, S100A, Snail-1, and HGF) and 6 stem cell markers (ALDH1, SOX2, CD24, CD44, CD54, and CD133) in 119 early gastric cancer specimens using immunohistochemistry. Because protein expression is heterogeneous in gastric cancer, we analyzed the expression of these markers in two selected regions (one each at the superficial zone and the deep invasive front).

RESULTS

Expression of E-cadherin, MMP7, HGF, and CD133 at the deep invasive front was associated with the absence of lymph node metastasis (P=0.013, 0.018, <0.001, and 0.026, respectively). Presence of diffuse-type component, lymphatic invasion, and lack of expression of HGF and CD133 at the deep invasive front were independent predictive markers of lymph node metastasis (P=0.019, <0.001, 0.015, and 0.047, respectively).

CONCLUSIONS

Lymph node metastasis is strongly associated with expression status of HGF and CD133 at the deep invasive front, suggesting the usefulness of these proteins as independent predictive markers of lymph node metastasis in early gastric cancer.

Autocrine and Paracrine Mechanisms Promoting Chemoresistance in Cholangiocarcinoma

Resistance to conventional chemotherapeutic agents, a typical feature of cholangiocarcinoma, prevents the efficacy of the therapeutic arsenal usually used to combat malignancy in humans. Mechanisms of chemoresistance by neoplastic cholangiocytes include evasion of drug-induced apoptosis mediated by autocrine and paracrine cues released in the tumor microenvironment. Here, recent evidence regarding molecular mechanisms of chemoresistance is reviewed, as well as associations between well-developed chemoresistance and activation of the cancer stem cell compartment. It is concluded that improved understanding of the complex interplay between apoptosis signaling and the promotion of cell survival represent potentially productive areas for active investigation, with the ultimate aim of encouraging future studies to unveil new, effective strategies able to overcome current limitations on treatment.

DLL4 overexpression increases gastric cancer stem/progenitor cell self-renewal ability and correlates with poor clinical outcome via Notch-1 signaling pathway activation

Gastric cancer is one of the most common malignant diseases, and poses a serious threat to the quality of human life. Gastric cancer stem/progenitor cells (GCSPCs) have critical effects on tumor formation, affecting specific features of self‐renewal and differentiation and playing a critical role in metastasis. The Notch‐1 pathway is crucially important to GCSPCs and is regulated by DLL4. In this study, DLL4 and Nestin levels were measured in 383 gastric cancer tissue samples by immunohistochemistry, and the clinico‐pathological features of patients assessed. After DLL4 silencing in selected gastric cancer cell lines, the expression of GCSPC markers and colony formation ability were analyzed and the self‐renewal and differentiation capacities of the cells were evaluated. The relationship between DLL4 levels and Notch‐1 signaling pathway effector amounts was assessed via Western blotting and immunofluorescence. Finally, the tumor formation ability of the gastric cancer cells was evaluated with different levels of DLL4 and multiple cell densities in vivo. Our results indicate that DLL4 expression is associated with TNM stage and cancer metastasis, with high amounts of DLL4 leading to poor outcome. DLL4 silencing inhibited the self‐renewal ability of GCSPCs and increased their multidifferentiation capacity, resulting in reduced GCSPC ratios. DLL4 knockdown also blocked the Notch‐1 pathway, weakening invasion ability and resistance to 5‐FU chemotherapy. In vivo, DLL4 silencing inhibited the tumor formation ability of GCSPCs. In conclusion, DLL4 affects GCSPC stemness, altering their pathological behavior. DLL4 silencing inhibits GCSPC metastatic potential both in vitro and in vivo by impeding Notch‐1 signaling pathway activation, indicating that DLL4 may be a new potential therapeutic target.

ALDH1A1-overexpressing cells are differentiated cells but not cancer stem or progenitor cells in human hepatocellular carcinoma

Aldehyde dehydrogenase 1A1 (ALDH1A1) is considered to be a cancer stem cell marker in several human malignancies. However, the role of ALDH1A1 in hepatocellular carcinoma (HCC) has not been well elucidated. In this study, we investigated the relationship between ALDH1A1 and clinicopathological findings and examined whether ALDH1A1 deserves to be a cancer stem cell marker in HCC. Sixty HCC samples obtained from surgical resection were collected for immunohistochemical (IHC) staining. Of these 60 samples, 47 samples of HCC tumorous and non-tumorous tissues were evaluated with qRT-PCR. There was no significant difference in the ALDH1A1-mRNA level between tumorous and non-tumorous tissues. Tumorous ALDH1A1-mRNA level had no relationship with the clinicopathological features. Immunoreactivity of ALDH1A1 was classified into two groups based on the percentage of ALDH1A1-overexpressing cells. The ALDH1A1-high group was significantly associated with low serum levels of α-fetoprotein, small tumor diameter, very little lymphovascular invasion, more differentiated pathology and good stage. The ALDH1A1-high group showed more favorable prognosis for recurrence-free survival. In double-staining IHC, ALDH1A1 was not co-expressed with BMI1, EpCAM, CD13, CD24, CD90 and CD133, which reported as cancer stem cell markers in HCC. In conclusion, ALDH1A1-overexpressing cells could appear to be differentiated cells rather than cancer stem cells in HCC.

Expression of Molecular Differentiation Markers Does Not Correlate with Histological Differentiation Grade in Intrahepatic Cholangiocarcinoma

The differentiation status of tumor cells, defined by histomorphological criteria, is a prognostic factor for survival of patients affected with intrahepatic cholangiocarcinoma (ICC). To strengthen the value of morphological differentiation criteria, we wished to correlate histopathological differentiation grade with expression of molecular biliary differentiation markers and of microRNAs previously shown to be dysregulated in ICC. We analysed a series of tumors that were histologically classified as well, moderately or poorly differentiated, and investigated the expression of cytokeratin 7, 19 and 903 (CK7, CK19, CK903), SRY-related HMG box transcription factors 4 and 9 (SOX4, SOX9), osteopontin (OPN), Hepatocyte Nuclear Factor-1 beta (HNF1β), Yes-associated protein (YAP), Epithelial cell adhesion molecule (EPCAM), Mucin 1 (MUC1) and N-cadherin (NCAD) by qRT-PCR and immunostaining, and of miR-31, miR-135b, miR-132, miR-200c, miR-221 and miR-222. Unexpectedly, except for subcellular location of SOX9 and OPN, no correlation was found between the expression levels of these molecular markers and histopathological differentiation grade. Therefore, our data point toward necessary caution when investigating the evolution and prognosis of ICC on the basis of cell differentiation criteria.

Cancer stem cell marker expression alone and in combination with microvascular invasion predicts poor prognosis in patients undergoing transplantation for hepatocellular carcinoma

BACKGROUND

The cancer stem cell hypothesis provides an explanation for hepatocellular carcinoma (HCC) heterogeneity. We investigated the expression of CD44 and CD133 alone and in combination with microvascular invasion (MVI) as predictors of prognosis in patients undergoing liver transplantation for HCC.

METHODS

Explanted livers from 95 patients transplanted for HCC were analyzed. Marker expression was evaluated by immunofluorescence.

RESULTS

Seventy-seven patients were male with a mean age of 56 years. The most common etiologies of cirrhosis were hepatitis C (50%) and alcoholic liver disease (41%). Forty-one patients had laboratory model for end-stage liver disease score greater than 15. Overall survival (OS) at 1-, 3-, and 5-years was 86%, 75%, and 64%, respectively. Recurrence rate was 13% with a median follow-up of 64 months. The 5-year OS was significantly lower in those patients with MVI and CD44 (36.9%) or CD133 (40%). CD44(+) and CD133(+) correlated with increased risk of poorly differentiated HCC, and elevated alpha-fetoprotein levels. In combination with MVI, both markers were independently associated with increased recurrence and worse OS (recurrence P < .003, odds ratio = 8.05; P = .001, odds ratio = 9.5, survival P = .001, HR = 3.7; P = .004, HR = 3.2 respectively).

CONCLUSIONS

CD44 or CD133 alone and in combination with MVI are independent predictors of poor prognosis in patients undergoing transplantation for HCC.

Risk factors and patterns of early recurrence after curative hepatectomy for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) often recurs after curative hepatectomy; and early recurrence after hepatectomy (ERAH) is associated with poor prognosis. This study aimed to clarify risk factors and disease patterns for ERAH.

METHODS

We retrospectively analyzed clinicopathological factors of 232 patients who underwent initial curative hepatectomies for HCC between April 2000 and March 2013, and examined associated risk factors and early recurrence patterns by liver function status (as indicated by indocyanine green retention rate at 15 min [ICGR15]).

RESULTS

Patients who experienced recurrence within 6 months after hepatectomy (i.e., ERAH) had significantly shorter survival than those with longer disease-free intervals (P < 0.001). In multivariate analysis, microvascular invasion (mVI; P = 0.034) and ICGR15 ≥ 16% (P = 0.010) were independent risk factors for ERAH. In the ICGR1<16% subgroup, positive L3-AFP (P = 0.04), tumor size ≥ 5 cm (P = 0.011), surgical margin = 0 (P = 0.0103), mVI (P = 0.034), and extrahepatic recurrence were significant predictors of ERAH; in the ICGR15 ≥ 16%, subgroup, multiple tumors (P = 0.046) were identified as a risk factor for ERAH; however, this group did not experience much extrahepatic recurrence.

CONCLUSIONS

ERAH was associated with mVI and ICGR15 ≥ 16%. Recurrence patterns and risk factors vary by liver function status, which should be considered in forming management strategies for early recurrence of HCC after curative hepatectomy.

Tumor Microenvironment Versus Cancer Stem Cells in Cholangiocarcinoma: Synergistic Effects?

Cholangiocarcinoma (CCAs) may be defined as tumors that derived from the biliary tree with the differentiation in the biliary epithelial cells. This tumor is malignant, extremely aggressive with a poor prognosis. It can be treated surgically and its pathogenesis is poorly understood. The tumor microenvironment (TME) is a very important factor in the regulation of tumor angiogenesis, invasion, and metastasis. Besides cancer stem cells (CSCs) can modulate tumor growth, stroma formation, and migratory capability. The initial stage of tumorigenesis is characterized by genetic mutations and epigenetic alterations due to intrinsic factors which lead to the generation of oncogenes thus inducing tumorigenesis. CSCs may result from precancerous stem cells, cell de-differentiation, normal stem cells, or an epithelial-mesenchymal transition (EMT). CSCs have been found in the cancer niche, and EMT may occur early within the tumor microenvironment. Previous studies have demonstrated evidence of cholangiocarcinoma stem cells (CD133, CD24, EpCAM, CD44, and others) and the presence of these markers has been associated with malignant potential. The interaction between TME and cholangiocarcinoma stem cells via signaling mediators may create an environment that accommodates tumor growth, yielding resistance to cytotoxic insults (chemotherarapeutic). While progress has been made in the understanding of the mechanisms, the interactions in the tumorigenic process still remain a major challenge. Our review, addresses recent concepts of TME-CSCs interaction and will emphasize the importance of early detection with the use of novel diagnostic mechanisms such as CCA-CSC biomarkers and the importance of tumor stroma to define new treatments. J. Cell. Physiol. 231: 768-776, 2016. © 2015 Wiley Periodicals, Inc.

Downregulated expression of PHLDA1 protein is associated with a malignant phenotype of cholangiocarcinoma

Cholangiocarcinoma is one of the most aggressive types of malignancy, and is associated with poor patient prognosis. Recent findings suggest that a decrease in pleckstrin homology-like domain family A, member 1 (PHLDA1) expression is significant in the induction of cell migration and tumor invasion. The clinicopathological significance of the expression of PHLDA1, and its potential correlation with the expression of CD133 in cholangiocarcinoma have remained to be elucidated. In the present study, PHLDA1 protein expression was investigated by immunohistochemical analysis of 218 cholangiocarcinoma tissue samples, as well as 30 para-neoplastic and 20 normal bile ducts. The expression status of PHLDA1 and CD133 was determined, and these results were analyzed against the age, gender, tumor location and size, histological grade, clinical stage and overall mean survival time of the patients. The expression of PHLDA1 protein was markedly decreased in 35.3% of cholangiocarcinomas, compared with that of the para-neoplastic and normal cholangiocytes. Carcinomas with loss of expression of PHLDA1 were significantly correlated with the tumor site (P=0.001), histological grade (P=0.020) and clinical stage (P=0.0001), but not with age (P=0.085), gender (P=0.456) or size (P=0.413), respectively. Kaplan-Meier survival analysis indicated that the loss of expression of PHLDA1 was significantly correlated with the overall survival time (Log rank=193.861; P=0.0001). Furthermore, the expression of PHLDA1 was found to be inversely correlated with the expression of CD133 (γ=-0.142; P=0.036). These findings suggested that the decreased expression of PHLDA1 may be significant in the carcinogenesis and progression of cholangiocarcinoma, and may represent a novel adjunct marker of disease prognosis.

Cancer stem cells in primary liver cancers: pathological concepts and imaging findings

There is accumulating evidence that cancer stem cells (CSCs) play an integral role in the initiation of hepatocarcinogenesis and the maintaining of tumor growth. Liver CSCs derived from hepatic stem/progenitor cells have the potential to differentiate into either hepatocytes or cholangiocytes. Primary liver cancers originating from CSCs constitute a heterogeneous histopathologic spectrum, including hepatocellular carcinoma, combined hepatocellular-cholangiocarcinoma, and intrahepatic cholangiocarcinoma with various radiologic manifestations. In this article, we reviewed the recent concepts of CSCs in the development of primary liver cancers, focusing on their pathological and radiological findings. Awareness of the pathological concepts and imaging findings of primary liver cancers with features of CSCs is critical for accurate diagnosis, prediction of outcome, and appropriate treatment options for patients.

Decreased expression of TFPI-2 correlated with increased expression of CD133 in cholangiocarcinoma

BACKGROUND

Recent findings suggest decreasing TFPI-2 expression plays a significant role in inhibiting cell migration and tumor invasion. The clinicopathological significance of the expression of TFPI-2 and its possible correlation with the expression of CD133 in cholangiocarcinoma remains to be solved.

METHODS

We investigated if TFPI-2 was involved in the clinicopathological significance of cholangiocarcinoma. An immunohistochemical method was used to detect 218 cases of cholangiocarcinoma, 30 para-neoplastic and 20 normal bile ducts for their expression status of TFPI-2 and CD133, and then the results were analyzed with the patient's age, sex, tumor site and the histological grade, clinical stage as well as overall mean survival time.

RESULTS

Compared with the para-neoplastic and normal cholangiocytes, the expression of TFPI-2 was obviously decreased while the expression of CD133 in carcinoma cells was increased. Carcinomas with low expression of TFPI-2 were significantly corresponding to the tumor site (P = 0.006), size (P = 0.005), histological grade (P = 0.0001) and clinical stage (P = 0.0001), but not to the age (P = 0.066) and sex (P = 0.411), respectively. By Kaplan-Meier survival analysis, the low expression of TFPI-2 was significantly correlative with the overall survival time (P = 0.0001). Further, the expression of TFPI-2 was found inversely correlative with the expression of CD133 (g = -0.3876, P < 0.0001).

CONCLUSIONS

Our finding suggests that the decreased expression of TFPI-2 may play an important role in the carcinogenesis and progression, and may become a new adjunct marker in the diagnosis and prognosis in cholangiocarcinoma. The expression of TFPI-2 may be inversely correlative with the expression of CD133.

Impact of microenvironment and stem-like plasticity in cholangiocarcinoma: molecular networks and biological concepts

Clinical complexity, anatomic diversity and molecular heterogeneity of cholangiocarcinoma (CCA) represent a major challenge in the assessment of effective targeted therapies. Molecular and cellular mechanisms underlying the diversity of CCA growth patterns remain a key issue of clinical concern. Crucial questions comprise the nature of the CCA-origin, the initial target for cellular transformation as well as the relationship with the cancer stem cells (CSC) concept. Additionally, since CCA often develops in the context of an inflammatory milieu (cirrhosis and cholangitis), the stromal compartment or tumour microenvironment (TME) likely promotes initiation and progression of this malignancy, contributing to its heterogeneity. This review will emphasize the dynamic interplay between stem-like intrinsic and TME-extrinsic pathways, which may represent novel options for multi-targeted therapies in CCA.

MicroRNA-144 suppresses cholangiocarcinoma cell proliferation and invasion through targeting platelet activating factor acetylhydrolase isoform 1b

Background

MicroRNAs are endogenous non-coding RNAs that play important roles in a wide variety of biological processes such as apoptosis, development, aging and cancer. The aberrant expression of miRNAs may contribute to phenotypic features of malignant cells, including resistance to chemotherapy. However, in cholangiocarcinoma (CCA) the correlation between miRNAs and their potential roles in CCA remains unclear.

Methods

MicroRNA profiles were analyzed in three pairs of CCA tumor specimens and non-tumorous-paired biliary tissues using Agilent microRNA microarrays. Expression of selected miRNAs was further confirmed in CCA tissues and CCA cell lines by q-PCR. The effects of miR-144 were evaluated by cell proliferation, migration, transwell, and tumorigenicity assays. Expression of LIS1 (platelet-activating factor acetylhydrolase isoform 1b) was assessed in CCA specimens and CCA cell lines by q-PCR and western blot. Targeting of LIS1 by miR-144 was confirmed by luciferase reporter assays.

Results

We found that the expression of 28 miRNAs in CCA tissues was significantly different from their corresponding adjacent normal bile duct tissues. We focused on miR-144 which was significantly down-regulated in CCA tissues. Reintroduction of miR-144 in CCA cell lines not only inhibited cell growth, but also significantly reduced cell migration and invasion capacities compared with controls. Luciferase assays and western blots verified LIS1 as a direct target of miR-144, and knocking-down LIS1 has similar effect with overexpression of miR-144 in CCA cell lines. Moreover, overexpression of miR-144 expression could suppress tumor growth in nude mice.

Conclusions

Our results showed that miR-144 was reduced in CCA tissues and suggested that miR-144 may be an essential suppresser of CCA cell proliferation and invasion through targeting LIS1.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-917) contains supplementary material, which is available to authorized users.

Decreased Expression of Stem Cell Markers by Simvastatin in 7,12-dimethylbenz(a)anthracene (DMBA)–induced Breast Cancer

Simvastatin, a competitive inhibitor of HMG-CoA reductase widely used in the treatment and prevention of hyperlipidemia-related diseases, has recently been associated to in vitro anticancer stem cell (CSC) actions. However, these effects have not been confirmed in vivo. To assess in vivo anti-CSC effects of simvastatin, female Sprague-Dawley rats with 7,12-dimethyl-benz(a)anthracene (DMBA)–induced mammary cancer and control animals were treated for 14 days with either simvastatin (20 or 40 mg/kg/day) or soybean oil ( N = 60). Tumors and normal breast tissues were removed for pathologic examination and immunodetection of CSC markers. At 40 mg/kg/day, simvastatin significantly reduced tumor growth and the expression of most CSC markers. The reduction in tumor growth (80%) could not be explained solely by the decrease in CSCs, since the latter accounted for less than 10% of the neoplasia (differentiated cancer cells were also affected). Stem cells in normal, nonneoplastic breast tissues were not affected by simvastatin. Simvastatin was also associated with a significant decrease in proliferative activity but no increase in cell death. In conclusion, this is the first study to confirm simvastatin anti-CSC actions in vivo, further demonstrating that this effect is specific for neoplastic cells, but not restricted to CSCs, and most likely due to inhibition of cell proliferation.

Cancer stem-like sphere cells induced from de-differentiated hepatocellular carcinoma-derived cell lines possess the resistance to anti-cancer drugs

BACKGROUND

Cancer stem cells (CSCs) are thought to play important roles in therapy-resistance. In this study, we induced cancer stem-like cells from hepatocellular carcinoma (HCC) cell lines using a unique medium, and examined their potential for resistance to anti-cancer drugs.

METHODS

The human HCC cell lines SK-HEP-1 (SK), HLE, Hep 3B, and HuH-7 were used to induce cancer stem-like cells with our sphere induction medium supplemented with neural survival factor-1. NANOG and LIN28A were examined as stemness markers. Several surface markers for CSC such as CD24, CD44, CD44 variant, and CD90 were analyzed by flow-cytometry. To assess the resistance to anti-cancer drugs, the MTS assay, cell cycle analysis, and reactive oxygen species (ROS) activity assay were performed.

RESULTS

Poorly differentiated HCC derived SK and undifferentiated HCC derived HLE cell lines efficiently formed spheres of cells (SK-sphere and HLE-sphere), but well-differentiated HCC-derived HuH-7 and Hep 3B cells did not. SK-spheres showed increased NANOG, LIN28A, and ALDH1A1 mRNA levels compared to parental cells. We observed more CD44 variant-positive cells in SK-spheres than in parental cells. The cell viability of SK-spheres was significantly higher than that of SK cells in the presence of several anti-cancer drugs except sorafenib (1.7- to 7.3-fold, each P < 0.05). The cell cycle of SK-spheres was arrested at the G0/G1 phase compared to SK cells. SK-spheres showed higher ABCG2 and HIF1A mRNA expression and lower ROS production compared to parental cells.

CONCLUSION

Our novel method successfully induced cancer stem-like cells, which possessed chemoresistance that was related to the cell cycle, drug efflux, and ROS.

Epstein-Barr virus-associated lymphoepithelioma-like cholangiocarcinoma: a rare variant of intrahepatic cholangiocarcinoma with favourable outcome

AIMS

Lymphoepithelioma-like cholangiocarcinoma (LELCC) is a rare variant of intrahepatic cholangiocarcinoma (IHCC). Only 16 cases have reported previously in the literature, and about 62.5% of these cases were associated with Epstein-Barr virus (EBV).

METHODS AND RESULTS

We present the largest series (seven cases) of LELCC with descriptions of clinical and pathological characteristics, investigations of aberrant DNA methylation and mutation analyses of EGFR and KRAS. The evaluation also included 11 cases of stage-matched conventional IHCC for comparison.

RESULTS

All seven patients of LELCC were female and had stage I disease. LELCC had significantly better 2- and 5-year overall survival than IHCC (100% versus 52.8%, and 100% versus 13.2%, respectively, P = 0.003). All seven LELCCs were EBV-associated and composed exclusively of adenocarcinoma with varied glandular differentiation, dense lymphoplasmacytic infiltrate, and variable expression of biliary-type cytokeratins (CK7 and CK19) and stemness markers (CD133 and EpCAM). Gene hypermethylation was more frequent in LELCC than IHCC. CRBPI (85.7% versus 9.1%, P < 0.003) and CRBPIV (85.7% versus 0%, P < 0.001) showed statistically higher methylation frequencies in LELCC than IHCC. No LELCC harboured any EGFR or KRAS mutation.

CONCLUSION

Epstein-Barr virus-associated LELCC is a variant of IHCC, characterized by marked female predominance, favourable overall survival and distinctively frequent DNA hypermethylation.

Human prominin-1 (CD133) is detected in both neoplastic and non-neoplastic salivary gland diseases and released into saliva in a ubiquitinated form

Prominin-1 (CD133) is physiologically expressed at the apical membranes of secretory (serous and mucous) and duct cells of major salivary glands. We investigated its expression in various human salivary gland lesions using two distinct anti-prominin-1 monoclonal antibodies (80B258 and AC133) applied on paraffin-embedded sections and characterized its occurrence in saliva. The 80B258 epitope was extensively expressed in adenoid cystic carcinoma, in lesser extent in acinic cell carcinoma and pleomorphic adenoma, and rarely in mucoepidermoid carcinoma. The 80B258 immunoreactivity was predominately detected at the apical membrane of tumor cells showing acinar or intercalated duct cell differentiation, which lined duct- or cyst-like structures, and in luminal secretions. It was observed on the whole cell membrane in non-luminal structures present in the vicinity of thin-walled blood vessels and hemorrhagic areas in adenoid cystic carcinoma. Of note, AC133 labeled only a subset of 80B258–positive structures. In peritumoral salivary gland tissues as well as in obstructive sialadenitis, an up-regulation of prominin-1 (both 80B258 and AC133 immunoreactivities) was observed in intercalated duct cells. In most tissues, prominin-1 was partially co-expressed with two cancer markers: carcinoembryonic antigen (CEA) and mucin-1 (MUC1). Differential centrifugation of saliva followed by immunoblotting indicated that all three markers were released in association with small membrane vesicles. Immuno-isolated prominin-1–positive vesicles contained CEA and MUC1, but also exosome-related proteins CD63, flotillin-1, flotillin-2 and the adaptor protein syntenin-1. The latter protein was shown to interact with prominin-1 as demonstrated by its co-immunoisolation. A fraction of saliva-associated prominin-1 appeared to be ubiquitinated. Collectively, our findings bring new insights into the biochemistry and trafficking of prominin-1 as well as its immunohistochemical profile in certain types of salivary gland tumors and inflammatory diseases.

Expression and diagnostic values of calretinin and CK5/6 in cholangiocarcinoma

BACKGROUND

Mesothelin, a mesothelial marker, has been found expressed in and as a potential treatment target of cholangioacarcinoma (CC). It is possible that CC may be derived from the cells sharing mesothelial markers. However, the expression of other mesothelial markers in CC is largely unknown.

METHODS

Thirty CC cases (10 extrahepatic and 20 intrahepatic) were retrieved from our institutional archive. The immunohistochemical study of Calretinin (DC8), WT1 (6F-H2), Lymphatic Endothelial Marker (D2-40), CK5/6 (D5/16 B4) and CK19 (b170) was done on formalin fixed paraffin embedded sections for 2-3 blocks of each case. We compared the expression levels between CC and normal bile duct (NBD) on the same block.

RESULTS

All of the CC and NBD are positive for CK19 (23/23) and negative for WT1 (0/23) and D2-40 (0/23), except one CC positive for D2-40(1/30, 3.3%) and one NBD positive for WT1 (1/23, 4.3%). Calretinin immunoreactivity was detected in 52.2% (12/23) of CC, but none in NBD (0/23). CK5/6 was also detectable in 73.3% (22/30) of CC and all NBD (30/30). Increased expression of calretinin and reduced expression of CK5/6 were more likely associated with CC than NBD (P < 0.001 and P = 0.002, respectively). The sequential staining pattern of positive calretinin and negative CK5/6 in calretinin negative cases has a sensitivity of 69.57% and a specificity of 100% for differentiating CC from NBD. CK5/6 expression was also more likely associated with well-differentiated CC (7/7 versus 12/20 in moderately differentiated, and 9/10 in poorly differentiated, P = 0.019) and extrahepatic CC (10/10 versus 12/20 in intrahepatic, P = 0.029), but there was no association between the calretinin expression and the CC grade or location.

CONCLUSION

Calretinin and CK5/6 immunohistochemical stains may be useful for diagnosing a CC. Their immunohistochemical results should be interpreted with caution in the cases with differential diagnoses of mesothelioma and CC. A full mesothelioma panel, including WT1 and/or D2-40, is recommended to better define a mesothelial lineage. The biology of calretinin and CK5/6 expression in CC is unclear, but might shed light on identifying therapeutic targets for CC.

Clinicopathological significance of cancer stem cells marked by CD133 and KAI1/CD82 expression in laryngeal squamous cell carcinoma

Background

Presently, CD133 is one of the hottest markers to characterize cancer stem cells and KAI1/CD82 is reported as an important marker for the metastasis and prognosis of many cancers. The purpose of our study is to explore the relationship between cancer stem cells (CSCs) marked by CD133 and KAI1/CD82 expression and the clinicopathological characteristics of patients with laryngeal squamous cell carcinoma (LSCC).

Methods

Immunohistochemical analysis was used to detect the expression of CD133 and KAI1/CD82 in 83 archival surgical specimens of human LSCC and 83 cases of normal laryngeal tissues.

Results

In LSCC, positive rates of 49.4% and 41.0% were obtained for CD133 and KAI1/CD82, respectively. The expression of CD133 in LSCC tissues was significantly higher than that in normal tissues (P < 0.001), and the expression of CD133 was positively associated with pTNM stage (P = 0.005), pathological grade (P = 0.001), and lymph node metastasis (P < 0.001). The reduced expression of KAI1/CD82 was present in LSCC tissues. The positive rate of KAI1/CD82 expression was negatively correlated with pTNM stage (P = 0.014), pathological grade (P < 0.001), and lymph node metastasis (P = 0.007). A correlation analysis showed that there was a negative relationship between the expression of CD133 and KAI1/CD82 protein in LSCC tissues (P < 0.001). By Kaplan-Meier analysis, the expression of CD133 was negatively correlated with overall survival (OS) (log-rank = 40.949, P < 0.001) and disease-free survival (DFS) (log-rank = 39.307, P < 0.001) time of LSCC. The expression of KAI1/CD82 was positively correlated with OS (log-rank = 40.279, P < 0.001) and DFS (log-rank = 39.271, P < 0.001) time of LSCC. Cox regression analysis: the expression of CD133 and KAI1/CD82, and pTNM stages were independent prognostic factors of LSCC (P < 0.05).

Conclusions

Thus the detection of CD133 and KAI1/CD82 proteins may be used as a potential indicator of LSCC prognosis.

Patients with CD133-negative colorectal liver metastasis have a poor prognosis after hepatectomy

BACKGROUND

The prognostic factors for patients with colorectal cancer liver metastasis (L-Mets) have not been fully described.

METHODS

Resected specimens were obtained surgically from 1998 to 2008 at our university hospital. We investigated whether the status of two primary lesion cancer stem biomarkers, CD44 and CD133, were maintained in L-Mets and whether these markers were L-Mets prognostic factors. To investigate the CD133 and CD44 status, proliferation, invasiveness, and chemoresistance were examined immunohistochemically by using MIB-1, E-cadherin, and ABC-G2.

RESULTS

The CD44-positive rate in primary lesions and L-Mets was 41.4 and 58.7 %, respectively. There was no correlation of CD44 expression between primary lesions and L-Mets (r = 0.250, p = 0.071). The CD133-positive rate in primary lesions and L-Mets was 53.6 and 44.6 %, respectively. There was no correlation of CD133 expression between primary lesions and L-Mets (r = 0.219, p = 0.135). In the CD133-negative group, the MIB-1 index was significantly higher than in the CD133-positive group (61.6 vs. 46.3 %, p = 0.003), and E-cadherin expression was significantly lower in the CD133-negative group compared with the CD133-positive group (29.3 vs. 46.8 %, p = 0.001). Absence of CD133 expression in L-Mets correlated with poor overall survival (p = 0.006), and multivariate regression analysis showed that it was an independent marker for poor survival (hazard ratio 0.320, p = 0.0016).

CONCLUSIONS

The absence of CD133 expression in L-Mets was an independent marker and a poor prognostic factor, possibly because of increased proliferation and invasiveness.

The roles of transforming growth factor-β, Wnt, Notch and hypoxia on liver progenitor cells in primary liver tumours (Review)

Primary liver tumours have a high incidence and mortality. The most important forms are hepatocellular carcinoma and intrahepatic cholangiocarcinoma, both can occur together in the mixed phenotype hepatocellular-cholangiocarcinoma. Liver progenitor cells (LPCs) are bipotential stem cells activated in case of severe liver damage and are capable of forming both cholangiocytes and hepatocytes. Possibly, alterations in Wnt, transforming growth factor-β, Notch and hypoxia pathways in these LPCs can cause them to give rise to cancer stem cells, capable of driving tumourigenesis. In this review, we summarize and discuss current knowledge on the role of these pathways in LPC activation and differentiation during hepatocarcinogenesis.

Inflammation-related DNA damage and expression of CD133 and Oct3/4 in cholangiocarcinoma patients with poor prognosis

Nitrative and oxidative DNA damage plays an important role in inflammation-related carcinogenesis. Chronic inflammation such as parasite infection and primary sclerosing cholangitis can be an etiological factor of cholangiocarcinoma. Using a proteomic approach and double-fluorescent staining, we identified high expression and colocalization of albumin and cytokeratin-19 in liver fluke-associated cholangiocarcinoma tissues, compared with normal livers from cholangiocarcinoma patients and cadaveric donors, respectively. Albumin was detected not only in cells of hyperplastic bile ducts and cholangiocarcinoma, but also in liver stem/progenitor cell origin, such as canal of Hering, ductules, and ductular reactions, suggesting the involvement of stem/progenitor cells in cholangiocarcinoma development. To clarify the involvement of liver stem/progenitor cells in cholangiocarcinoma, we examined several stem/progenitor cell markers (CD133, CD44, OV6, and Oct3/4) in cholangiocarcinoma tissues analyzed by immunohistochemical staining, and measured 8-oxodG levels by using HPLC-ECD as an inflammation-related DNA lesion. In addition, a stem/progenitor cell factor Bmi1, 8-nitroguanine (formed during nitrative DNA damage), DNA damage response (DDR) proteins (phosphorylated ATM and γ-H2AX), and manganese-SOD (Mn-SOD) were analyzed by immunohistochemistry. Stem/progenitor cell markers (CD133, OV6, CD44, and Oct3/4) were positively stained in 56, 38, 47, and 56% of 34 cholangiocarcinoma cases, respectively. Quantitative analysis of 8-oxodG revealed significantly increased levels in CD133- and/or Oct3/4-positive tumor tissues compared to negative tumor tissues, as well as 8-nitroguanine formation detected by immunohistochemistry. In the cases of CD44- and/or OV6-positive tissue, no significant difference was observed. Cholangiocarcinoma patients with CD133- and/or Oct3/4-positive tumor tissues showed significantly lower expression of Mn-SOD and higher DDR protein, γ-H2AX. Moreover, CD133- and/or Oct3/4-positive cholangiocarcinoma patients had significant associations with tumor histology types, tumor stage, and poor prognoses. Our results suggest that CD133 and Oct3/4 in cholangiocarcinoma are associated with increased formation of DNA lesions and the DDR protein, which may be involved in genetic instability and lead to cholangiocarcinoma development with aggressive clinical features.

Beclin 1 deficiency correlated with lymph node metastasis, predicts a distinct outcome in intrahepatic and extrahepatic cholangiocarcinoma

Autophagy can be tumor suppressive as well as promotive in regulation of tumorigenesis and disease progression. Accordingly, the prognostic significance of autophagy key regulator Beclin 1 was varied among different tumors. Here, we detected the clinicopathological and prognostic effect of Beclin 1 in the subtypes of intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC). Beclin 1 expression level was detected by immunohistochemistry staining in 106 ICC and 74 ECC patients. We found that Beclin 1 was lowly expressed in 126 (70%) cholangiocarcinoma patients, consist of 72 ICC and 54 ECC. Moreover, the cholangiocarcinoma patients with lymph node metastasis (N1) had a lower Beclin 1 level than that of N0 subgroup (P=0.012). However, we did not detect any correlations between Beclin 1 and other clinicopathological features, including tumor subtypes, vascular invasion, HBV infection, liver cirrhosis, cholecystolithiasis and TNM stage. Survival analysis showed that, compared with the high expression subset, Beclin 1 low expression was correlated with a poorer 3-year progression-free survival (PFS, 69.1% VS 46.8%, P=041) for cholangiocarcinoma. Importantly, our stratified univariate and multivariate analysis confirmed that Beclin 1 lowly expressed ICC had an inferior PFS as well as overall survival than ECC, particularly than that of Beclin 1 highly expressed ECC patients. Thus, our study demonstrated that Beclin 1low expression, correlated with lymph node metastasis, and might be a negative prognostic biomarker for cholangiocarcinoma. Combined Beclin 1 level with the anatomical location might lead to refined prognosis for the subtypes of ICC and ECC.

Clinical implications of microRNAs in liver cancer stem cells

The prognosis of patients diagnosed with hepatocellular carcinoma (HCC) is often dismal, mainly due to late presentation, high recurrence rate, and frequent resistance to chemotherapy and radiotherapy. Accumulating evidence on the differential microRNA (miRNA) expression patterns between non-tumor and HCC tissues or between liver cancer stem cells (CSCs) and non-CSC subsets and the significant clinical implications of these differences suggest that miRNAs are a promising, non-invasive marker for the prognosis and diagnosis of the disease. This perspective article summarizes the current knowledge of miRNAs in liver CSCs and highlights the need for further investigations of the role of miRNAs in regulating liver CSC subsets for possible future clinical applications.

Novel therapeutic target for cancer stem cells in hepatocellular carcinoma

Cancer is a disease of genetic and epigenetic alterations, which are emphasized as the central mechanisms of tumor progression in the multi-stepwise model. Discovery of rare subpopulations of cancer stem cells (CSCs) has created a new focus in cancer research. The heterogeneity of tumors can be explained with the help of CSCs supported by anti-apoptotic signaling. CSCs mimic normal adult stem cells by demonstrating unique characteristics of self-renewal and pluripotency, and the critical role for tumor growth and resistance to anti-cancer therapy. We found that CD13 was a surface marker for CSCs in human liver cancer cell lines and clinical samples, and that CD13+ CSCs were associated with a hypoxic marker in clinical hepatocellular carcinoma (HCC) sample, suggesting that CD13+ CSCs have the critical role in tumor growth and resistance to anti-cancer therapy in liver cancers. In this review article, we update recent findings regarding the involvement of CSCs, especially in HCC.

Recent advances in cancer stem cell research for cholangiocarcinoma

Cancer stem cells have been identified as cells with the capacity to self-renew and differentiate into multiple lineages of human malignancies. Cholangiocarcinoma is one of the most difficult intra-abdominal malignancies that can be treated using a surgical approach. Chemotherapy in addition to surgery is necessary to improve patient survival. However, its clinical benefit is limited, and, to date, no other effective anticancer drug is available for this disease. Several reports have shown the existence of cholangiocarcinoma stem cells. Cell surface antigens such as CD133, CD24, EpCAM, CD44, and others have been used to isolate cholangiocarcinoma stem cells. In general, enhanced expression of these markers in resected specimens of cholangiocarcinoma was associated with malignant potential. Distinct and specific pathways are expected to be present in cancer stem cells compared to other cancer cells that have no stem cell properties. To date, reports showing possible signaling pathways in cholangiocarcinoma stem cells are limited. More research is anticipated. Targeting therapies for surface molecular markers or specific signaling pathways of cholangiocarcinoma stem cells may be important in order to change the clinical outcome of patients with this disease. However, no clinical trial has been performed so far. This review will focus on the markers and signaling pathways used to define cholangiocarcinoma stem cells. A novel therapeutic approach of targeting cholangiocarcinoma stem cells will also be discussed.

Significance of CD133 expression in esophageal squamous cell carcinoma

Background

CD133 was recently reported to be a cancer stem cell marker and a prognostic marker for several tumors. However, few studies have investigated CD133 expression in esophageal squamous cell carcinoma (ESCC). Therefore, we examined whether CD133 could serve as a prognostic marker of ESCC and investigated the correlation between CD133 expression and the clinicopathological findings of ESCC patients and several markers.

Methods

We studied 86 ESCC patients who underwent curative surgery without neoadjuvant treatment at Tohoku University Hospital (Sendai, Japan) between January 2000 and December 2005. We analyzed tissue specimens by immunohistochemical staining for CD133, p53, p16, p27, murine double minute 2 (MDM2), Ki-67, and epidermal growth factor receptor (EGFR).

Results

Pathological tumor depth and tumor stage were significantly more advanced among CD133-negative patients than among CD133-positive patients. A log-rank test showed that CD133 immunoreactivity was significantly correlated with the overall survival of the patients (P = 0.049). However, multivariate analysis showed that it was not significantly correlated (P = 0.078). Moreover, CD133 was significantly positively correlated with p27 immunoreactivity (P = 0.0013) and tended to be positively correlated with p16 immunoreactivity (P = 0.057). In addition, p16 immunoreactivity was correlated with smoking history (P = 0.018), pathological lymph node status (P = 0.033), and lymphatic invasion (P = 0.018).

Conclusions

This study indicated that CD133 immunoreactivity is a good predictor of prognosis in ESCC patients. In addition, CD133 may play a role in the regulation of tumor cell cycle through p27 and p16 in ESCC. At present, it thus remains controversial whether CD133 expression is a valid prognostic marker for ESCC. To elucidate this relationship, further investigations are required.

Aberrant expression of CD133 in non-small cell lung cancer and its relationship to vasculogenic mimicry

Background

To investigate on expressions and clinical significances of CD133 protein and vasculogenic mimicry (VM) in primary non-small cell lung cancer (NSCLC).

Methods

The specimens of NSCLC from 305 Chinese patients with follow-up were analyzed for CD133 protein expression and VM by immunohistochemical and histochemical staining.

Results

In NSCLC, positive rates of 48.9% and 35.7% were obtained for CD133 and VM, respectively. The VM and expression of CD133 were significantly higher in carcinoma than in normal. There were a positive relationship between the VM and expression of CD133 and the tumor grade, lymph node metastasis and clinical stage (all P<0.05). The overall mean survival time of the patients with CD133 and VM positive expression was lower than that of patients with negative expression. Microvessel density (MVD) was positive corresponded with the grade, lymph node metastasis and clinical stage (all P<0.05). The overall mean survival time of the patients with MVD≥22’s group was shorter than that of patients with MVD<22’s group. Pathological-tumor-node-metastasis (pTNM) stage, positive expression of CD133 and VM, postoperative therapy and MVD were independent prognostic factors of NSCLC (P<0.05). Immunohistochemistry revealed an important intratumoral heterogeneity in all four CD133 expression profiles.

Conclusions

VM, MVD and expression of CD133 are related to differentiation, lymph node metastasis, clinical stage, and prognosis. It is suggested that CD133, VM and MVD should be considered as a potential marker for the prognosis.

CD133 expression predicts lung metastasis and poor prognosis in osteosarcoma patients: A clinical and experimental study

Identifying prognostic factors for osteosarcoma (OS) aids in the selection of patients who require more aggressive management. CD133 has been found to be a prognostic factor of certain tumor types. However, the association between CD133 expression and the prognosis of OS remains unknown. In this study, we analyzed the association of CD133 expression in OS with clinical factors and overall survival, and further investigated its potential role in metastasis in vitro. We found CD133 expression in 65.7% (46/70) of OS samples using immunohistochemistry, and it was positively correlated with lung metastasis analyzed by Chi-square test (P=0.002) and shorter overall survival time using the Kaplan-Meier method compared by log-rank test (P=0.000). Multivariate analysis showed that CD133 expression was an independent prognostic factor of patients with OS. To test for direct participation of CD133, we separated CD133⁺ and CD133⁻ cells in the MG63 cell line using magnetic-activated cell sorting and found that CD133⁺ cells were more active in migration by scratch wound-healing assay and invasion by Matrigel invasion assay compared with CD133⁻ cells. Elevated mRNA expression of the stemness gene octamer-binding transcription factor 4 (Oct-4) and NANOG, and the metastasis-related receptor C-X-C chemokine receptor type 4 (CXCR4) were also found in CD133⁺ cells by reverse transcription-polymerase chain reaction. Thus, expression of CD133 was correlated with lung metastasis and poor prognosis in OS patients. CD133⁺ cells may be a type of cancer stem cell with high expression of self-renewal capacity and metastasis-related genes.

[Liver transplantation for hilar cholangiocarcinoma]

Local non-resectable, hilar cholangiocarcinoma can be cured by performing a liver transplantation. The initially poor results after transplantation have significantly improved since neoadjuvant therapy protocols have been established. Therefore, hilar cholangiocarcinoma is now an accepted indication for liver transplantation in selected patients. This article summarizes the current state, recommendations and results of liver transplantation for these patients.

Prognostic value of the stem cell markers CD133 and ABCG2 expression in esophageal squamous cell carcinoma

In the light of increasing evidence supporting cancer stem cells (CSCs) theory, the expression of two stem cell markers, CD133 and adenosine triphosphate-binding cassette superfamily G member 2 (ABCG2), in esophageal squamous cell carcinoma (ESCC) was investigated, and their prognostic values were evaluated. Paraffin-embedded tissue sections of 110 ESCC patients were investigated using Immunohistochemistry. The association of CD133 and ABCG2 expression with clinicopathologic characteristics was analyzed by χ(2) test. Survival analysis was carried out using Kaplan-Meier method and Cox proportional hazards model. CD133 and ABCG2 expression were detected in 27.3% and 15.5% of ESCC patients, respectively. The presence of CD133-positive cancer cells was associated with tumor cell differentiation (P= 0.008) but not significantly related to the survival of ESCC patients (P= 0.085). ABCG2 expression was not associated with clinicopathologic characteristics but was a significant prognostic factor for adverse overall survival of ESCC patients (P= 0.005). The median overall survival time for ESCC patients with and without ABCG2 expression were 21.8 and >49.3 months, respectively. A combined analysis of CD133 and ABCG2 expression did not show that ESCC patients with coexpression of these two markers had a worse prognosis than those with only ABCG2 expression (P= 0.934). Moreover, ABCG2 expression was revealed to be an independent prognostic factor along with tumor node metastasis stage in multivariate analysis (hazard ratio of ABCG2, 3.38; 95% confidence interval, 1.61∼7.09; P= 0.001). By survival analysis based on tumor node metastasis stage of ESCC, the association between ABCG2 expression and the patients' prognosis was found significant in the group of relatively early stage (P= 0.005) and marginally significant in the group of relatively late stage (P= 0.058). This is the first time to report the presence of CD133-positive cancer cells in ESCC but not supporting its prognostic value and validity as a CSC marker for ESCC. ABCG2 expression was found to correlate with the survival of ESCC patients, especially those at relatively early stage, suggesting that ABCG2-positive cancer cells may represent a pool of CSCs in ESCC, and relatively early-stage patients with ABCG2 expression may deserve more intensive or targeted therapy.