Significance of immunohistochemical over-expression of CD44v6 as an indicator of malignant potential in esophageal squamous cell carcinoma

An adhesion based approach for the detection of esophageal cancer

Esophageal cancer has a 5 year survival rate of ∼20%. This dismal prognosis is due, in part, to the fact that esophageal cancer often presents at a late stage. Thus, there is a critical need for assays that enable the early detection of cancerous tissue within the esophagus. The luminal surface of the esophagus expresses signature molecule(s) at sites of transformation providing an avenue for the development of in situ assays that detect neoplastic growth within the esophagus. An attractive approach, receiving increased attention, is the endoscopic administration of particles conjugated with ligands to signature molecules present on transforming tissue. Detection of the particles within the esophagus, post-washing, would indicate the presence of the signature molecule and thus transforming tissue. In this work, we utilized cancerous and normal esophageal cells to provide in vitro proof of principle for this approach utilizing ligand-conjugated microspheres and demonstrate the need, and provide the framework for, engineering this technology. Specifically, the study (i) reveals selective increased expression of signature molecules on cancerous esophageal cells relative to normal cells; (ii) demonstrates selective binding of ligand-conjugated microspheres to cancerous esophageal cells relative to normal cells; (iii) demonstrates that the selective recognition of cancerous, relative to normal esophageal cells, is highly dependent on the biophysical design of the assay; and (iv) advocates utilizing the knowledge from the field of cell adhesion as a guide for the effective development of ligand-conjugated particle-based schemes that seek to detect esophageal oncogenesis in situ.

Circulating Tumor Cells Detected by the Expression of Cancer Stem Cell Markers CD90 and CD44 in Patients With Esophageal Cancer

Background

Epithelial cell adhesion molecule (EpCAM) is a marker for circulating tumor cells (CTCs) in various types of cancer. Cell surface antigens, such as CD90 and CD44, have been reported to be cancer stem cell (CSC) markers in esophageal squamous cell carcinoma (ESCC). The aim of this study was to assess the use of CD90 and CD44 as markers to identify clinically significant CTC subpopulations in ESCC.

Methods

We collected 3 mL of peripheral blood from 10 ESCC patients and 10 healthy volunteers to detect combined expression of EpCAM, CD90, and CD40 using flow cytometry.

Results

The number of EpCAM-positive cell counts (average ± SD) in the patients was significantly higher than healthy volunteers (29.1 ± 35.9 and 2.3 ± 2.5, P = 0.001). The proportions (average ±SD) of CD90- and CD44-positive cells in EpCAM-positive cells were 45.7% ± 42.4% and 98.7% ± 2.7%, respectively. EpCAM-positive/CD44-positive CTC counts, which was equivalent to EpCAM-positive CTC counts, correlated with pathologic V factors in the resected primary tumors (P > 0.01). EpCAM-positive/CD90-positive CTC counts, but not EpCAM-positive/CD90-negative CTC counts, correlated with pathologic V factors in the resected primary tumors (P = 0.01). Our results suggested that combined expression of EpCAM and CD90 may useful to detect CTC subsets, which have highly metastatic features in ESCC. CD44, on the other hand, is equivalent to EpCAM as a marker to detect CTCs in ESCC.

Autophagy supports generation of cells with high CD44 expression via modulation of oxidative stress and Parkin-mediated mitochondrial clearance

High CD44 expression is associated with enhanced malignant potential in esophageal squamous cell carcinoma (ESCC), amongst the deadliest of all human carcinomas. Although alterations in autophagy and CD44 expression are associated with poor patient outcomes in various cancer types, the relationship between autophagy and cells with high CD44 expression remains incompletely understood. In transformed esophageal keratinocytes, CD44^Low-CD24^High (CD44L) cells give rise to CD44^High-CD24^−/Low (CD44H) cells via epithelial-mesenchymal transition (EMT) in response to transforming growth factor (TGF)-β. We couple patient samples and xenotransplantation studies with this tractable in vitro system of CD44L to CD44H cell conversion to investigate the functional role of autophagy in generation of cells with high CD44 expression. We report that high expression of the autophagy marker cleaved LC3 expression correlates with poor clinical outcome in ESCC. In ESCC xenograft tumors, pharmacological autophagy inhibition with chloroquine derivatives depletes cells with high CD44 expression while promoting oxidative stress. Autophagic flux impairment during EMT-mediated CD44L to CD44H cell conversion in vitro induces mitochondrial dysfunction, oxidative stress and cell death. During CD44H cell generation, transformed keratinocytes display evidence of mitophagy, including mitochondrial fragmentation, decreased mitochondrial content and mitochondrial translocation of Parkin, essential in mitophagy. RNA interference-mediated Parkin depletion attenuates CD44H cell generation. These data suggest that autophagy facilitates EMT-mediated CD44H generation via modulation of redox homeostasis and Parkin-dependent mitochondrial clearance. This is the first report to implicate mitophagy in regulation of tumor cells with high CD44 expression, representing a potential novel therapeutic avenue in cancers where EMT and CD44H cells have been implicated, including ESCC.

Meta-Analysis of Prognostic and Clinical Significance of CD44v6 in Esophageal Cancer

CD44v6 is a cell adhesion molecule that plays an important role in the development and progression of esophageal cancer. However, the prognostic value and clinical significance of CD44v6 in esophageal cancer remains controversial. In the present study, we aimed to clarify these relationships through a meta-analysis.We performed a comprehensive search of studies from PubMed, EMBASE, Ovid library database, Google scholar, and Chinese National Knowledge Infrastructure databases that were published before June 2015. The odds ratio (OR) and pooled hazard ratio (HR) with the 95% confidence intervals (CI) were used to estimate the effects.Twenty-one studies including 1504 patients with esophageal cancer were selected to assess the prognostic value and clinical significance of CD44v6 in these patients. The results showed that the expression of CD44v6 was higher in esophageal cancer tissue than in normal colorectal tissue (OR=9.19, 95% CI=6.30-13.42). Moreover, expression of CD44v6 was higher in patients with lymphoid nodal metastasis, compared to those without (OR=6.91, 95% CI=4.81-9.93). The pooled results showed that CD44v6 was associated with survival in patients with esophageal cancer (HR = 2.47, 95% CI = 1.56-3.92). No significant difference in CD44v6 expression was found in patients with different histological types and tumor stages (both P>0.05). Moreover, no publication bias was found among the studies (all P > 0.05).This meta-analysis demonstrates that CD44v6 is associated with the metastasis of esophageal cancer and a poor prognosis, but is not associated with the histological types and tumor stages.

Highly sensitive and selective anticancer effect by conjugated HA-cisplatin in non-small cell lung cancer overexpressed with CD44

In spite of severe side effects, chemotherapy is widely used as a major anticancer treatment in non-small cell lung cancer (NSCLC). In order to enhance the therapeutic properties and reduce side effects, enormous efforts have been devoted to direct anticancer agents specifically to tumor tissues by the use of nanoparticles, or cancer cell marker attached drugs. However, cell-specific chemotherapy is still in its infancy and is not applicable to all types of cancers due to the complexity of the cancer occurrence and progress. In this study, we demonstrate that hyaluronan (HA)-conjugated cisplatin has highly selective and sensitive anticancer effects in NSCLC cells that overexpress the trans-membrane receptor, CD44, as HA is a specific ligand for CD44. In proliferation experiments, HA-conjugated cisplatin showed dramatic cell viability decreases (from 100% to 42.31%) in H1299 cells, which overexpress CD44, whereas no such change was observed in A549 and HFL1, which have little to no expression of CD44. More importantly, conjugation with HA decreased the dosage concentration of cisplatin by 50-fold for both cytotoxic and anti-metastatic effects. In addition, HA-cisplatin conjugate treatment selectively decreased migration (from 100% to 7.8%) and invasiveness (from 100% to 21.4%, respectively) of H1299. Based on our experimental results, we strongly believe that HA-cisplatin conjugate is a potential anticancer chemo-agent, which target CD44 overexpression in NSCLC, with minimal side effects and high therapeutic properties.

Expression and association of CD44v6 with prognosis in T2-3N0M0 esophageal squamous cell carcinoma

AIM

To investigate the expression of CD44v6 in stage T2-3N0M0 esophageal squamous cell carcinoma (ESCC) and its prognostic significance.

METHODS

The expression of CD44v6 in a series of 227 ESCC specimens was evaluated by immunohistochemistry (IHC). A reproducible semiquantitative method which took both staining percentage and intensity into account was applied for IHC scoring, and receiver operating characteristic (ROC) curve analysis was utilized to select the cut-off score for high or low IHC reactivity. Then, the correlations of CD44v6 expression with clinicopathological features of patients and its prognostic relevance were determined.

RESULTS

In the present study, the proportion of low CD44v6 expression was found significantly lower in Grade 3 of ESCC, than that of Grade 1 and Grade 2 of ESCC. There are no significant correlations between CD44v6 expression and other clinicopathological parameters including gender, age, tumor size, tumor location, depth of invasion and pathological stage. The Kaplan-Meier survival curves showed that up-regulated expression of CD44v6 indicated a poorer post-operative survival for ESCC patients of stage T2-3N0M0 (P=0.009), especially for those with T2 lesions (P=0.044) or with stage IIB diseases (P=0.005). Multivariate analysis also confirmed that CD44v6 expression [relative risk, 1.639; 95% confidence interval (CI): 1.142-2.354, P=0.007] and depth of invasion (relative risk, 1.487; 95% CI: 1.063-2.080, P=0.020) were independent prognostic factors.

CONCLUSIONS

Elevated CD44v6 expression may be an adverse prognostic indicator for patients with stage T2-3N0M0 ESCC, especially for those with T2 lesions or stage IIB diseases.

Expression of COX-2, CD44v6 and CD147 and relationship with invasion and lymph node metastasis in hypopharyngeal squamous cell carcinoma

To assess the expression of COX-2,CD44v6 and CD147 in hypopharyngeal squamous cell carcinomas and the three biomarkers correlation with tumor invasion and lymph node metastasis of Chinese people. 101 cases of surgically excised primary tumor were included in this study, and 40 tissues of epithelium adjacent to carcinoma were used as controls. We characterized the immunohistochemical expression of COX-2, CD44v6, and CD147 in141 formalin-fixed, paraffin-embedded tissues, and measured the mean optical density (OD) of the positive area to identify the expression of the three bio-markers and relationship with tumor invasion and lymph node metastasis. Our study demonstrates that the expression of the COX-2 and CD147 were significantly increased in carcinoma tissues compared to the epithelium adjacent to carcinoma. We also observed that the expression of COX-2, CD44v6, and CD147 were significantly associated with T classification, lymph node metastasis and clinical stage. There was strong significant correlation among the three biomarkers as well. Additionally, we indicated that recurrence and ≥P₅₀ level of COX-2 expression had an independent prognostic effect on prognosis. In conclusion, the three biomarkers play important roles in tumor invasion and lymph node metastases and might be valuable indicators of tumor metastasis in hypopharyngeal squamous cell carcinoma.

CD44 upregulation in E-cadherin-negative esophageal cancers results in cell invasion

E-cadherin is frequently lost during epithelial-mesenchymal transition and the progression of epithelial tumorigenesis. We found a marker of epithelial-mesenchymal transition, CD44, upregulated in response to functional loss of E-cadherin in esophageal cell lines and cancer. Loss of E-cadherin expression correlates with increased expression of CD44 standard isoform. Using an organotypic reconstruct model, we show increased CD44 expression in areas of cell invasion is associated with MMP-9 at the leading edge. Moreover, Activin A increases cell invasion through CD44 upregulation after E-cadherin loss. Taken together, our results provide functional evidence of CD44 upregulation in esophageal cancer invasion.

Tumor initiating cells in esophageal squamous cell carcinomas express high levels of CD44

Background

Esophageal Squamous Cell Carcinoma (ESCC) is a major subtype of esophageal cancer causing significant morbility and mortality in Asia. Mechanism of initiation and progression of this disease is unclear. Tumor initiating cells (TICs) are the subpopulation of cells which have the ability to self-renew, as well as, to drive initiation and progression of cancer. Increasing evidence has shown that TICs exist in a variety of tumors. However, the identification and characterization of TICs in esophageal carcinoma has remained elusive.

Methodology/Principal Findings

to identify TICs in ESCC, ESCC cell lines including two primary cells were used for screening suitable surface marker. Then colony formation assay, drug resistant assay and tumorigenicity assay in immune deficient mice were used to characterize TICs in ESCC. We found that just the CD44 expression correlated with tumorigenicity in ESCC cell lines. And then induced differentiation of ESCC cells by all-trans retinoic acid treatment led to decreased expression of CD44. The FACS isolated cell subpopulations with high CD44 expression showed increased colony formation and drug resistance in vitro, as well as significantly enhanced tumorigenicity in NOD/SICD mice, as compared to the low expressing CD44 ESCC cells.

Conclusions/Significance

our study has discovered a novel TIC surface marker, CD44, which can be utilized to enrich efficiently the TICs in ESCC. These findings will be useful for further studies of these cells and exploring therapeutic approaches.

Hyaluronan: From Biomimetic to Industrial Business Strategy

Hyaluronan (hyaluronic acid) is a naturally occurring polysaccharide of a linear repeating disaccharide unit consisting of β-(1→4)-linked D-glucopyranuronic acid and β-(1→3)-linked 2-acetamido-2-deoxy-D-glucopyranose, which is present in extracellular matrices, the synovial fluid of joints, and scaffolding that comprises cartilage.

In its mechanism of synthesis, its size, and its physico-chemical properties, hyaluronan is unique amongst other glycosaminoglycans. The network-forming, viscoelastic and its charge characteristics are important to many biochemical properties of living tissues. It is an important pericellular and cell surface constituent; its interaction with other macromolecules such as proteins, participates in regulating cell behavior during numerous morphogenic, restorative, and pathological processes in the body. The knowledge of HA in diseases such as various forms of cancers, arthritis and osteoporosis has led to new impetus in research and development in the preparation of biomaterials for surgical implants and drug conjugates for targeted delivery.

A concise and focused review on hyaluronan is timely. This review will cover the following important aspects of hyaluronan: (i) biological functions and synthesis in nature; (ii) current industrial production and potential biosynthetic processes of hyaluronan; (iii) chemical modifications of hyaluronan leading to products of commercial significance; and (iv) and the global market position and manufacturers of hyaluronan.

Carcinogen-altered genes in rat esophagus positively modulated to normal levels of expression by both black raspberries and phenylethyl isothiocyanate

Our recent study identified 2,261 dysregulated genes in the esophagi of rats that received a 1-week exposure to the carcinogen N-nitrosomethylbenzylamine (NMBA). We further reported that 1,323 of these genes were positively modulated to near-normal levels of expression in NMBA-treated animals that consumed dietary phenylethyl isothiocyanate (PEITC), a constituent of cruciferous vegetables. Herein, we report our results with companion animals that were fed a diet containing 5% freeze-dried black raspberries (BRB) instead of PEITC. We found that 462 of the 2,261 NMBA-dysregulated genes in rat esophagus were restored to near-normal levels of expression by BRB. Further, we have identified 53 NMBA-dysregulated genes that are positively modulated by both PEITC and BRB. These 53 common genes include genes involved in phase I and II metabolism, oxidative damage, and oncogenes and tumor suppressor genes that regulate apoptosis, cell cycling, and angiogenesis. Because both PEITC and BRB maintain near-normal levels of expression of these 53 genes, their dysregulation during the early phase of NMBA-induced esophageal cancer may be especially important in the genesis of the disease.

Effects of body-resistance strengthening and tumor-suppressing granules on immune adhesion function of red blood cells and expression of metastasis protein CD44 in tumor cells of patients with esophageal carcinoma

AIM: To investigate the effects of Fuzheng Yiliu granules (body-resistance strengthening and tumor-suppressing granules) in patients with esophageal carcinoma.

METHODS: We compared the immune adherent properties of red blood cells (RBCs), the expression of metastasis protein CD44, and the metastasis inhibition factor nm23, in esophageal carcinoma tumor cells of patients before and after radiotherapy in the presence and absence of orally administered Fuzheng Yiliu granules. Sixty-three hospitalized patients with esophageal carcinoma were treated with standard radiotherapy and randomly divided into treatment group (n = 30) treated with both radiotherapy and Fuzheng Yiliu granules and control group (n = 33) given radiotherapy only. Blood samples and tumor tissue were obtained before and after 21 d of treatment. The rosette rates for complement receptor type 3b (C3bRR) and immune complex receptor (ICRR) on RBCs were measured by erythrocyte immunological methods. Expression of CD44 and nm23 in tumor tissue sections was determined by immunohistochemical staining with monoclonal antibodies CD44v6 ad nm23H-1, respectively.

RESULTS: The positivity of RBC-C3bRR before and after 21 d of treatment increased from 7.78% ± 1.59% to 10.03% ± 2.01% in the double treatment group, while it changed only slightly from 7.18% ± 1.29% to 7.46% ± 1.12% in the radiotherapy group. The positive rate for RBC-ICRR decreased from 37.68% ± 2.51% to 22.55% ± 1.65% after the double treatment, and from 37.28% ± 2.41% to 24.69% ± 1.91% in radiotherapy group at the same time points. The difference in erythrocyte immune adherent function between the two groups was significant (P < 0.01, t-test). The CD44⁺-cases were reduced from 21 (70.00%) to 12 (40.00%) after treatment with Fuzheng Yiliu granules, whereas the CD44⁺-cases (69.70%) in the radiotherapy group remained unchanged. The difference between the treatment (40.00%) and control (69.70%) groups was significant (P < 0.05). Although the nm23⁺-cases were increased from 4 (13.33%) to 6 (20.00%) in the double treatment group and from 6 (18.18%) to 7 (21.21%) in the radiotherapy group, the difference was not significant (P > 0.05).

CONCLUSION: Fuzheng Yiliu granules enhance the immune adhesion function of RBCs and reduce the number of CD44⁺-cells in esophageal carcinoma patients, suggesting a potential role of these Chinese herbals in suppression of invasion and metastasis of malignant cells. However, this anti-metastatic effect has yet to be validated in vivo.