Clinicopathological significance of vascular endothelial growth factor (VEGF)-C in human esophageal squamous cell carcinomas

Lymphatic Tissue Bioengineering for the Treatment of Postsurgical Lymphedema

Lymphedema is characterized by progressive and chronic tissue swelling and inflammation from local accumulation of interstitial fluid due to lymphatic injury or dysfunction. It is a debilitating condition that significantly impacts a patient's quality of life, and has limited treatment options. With better understanding of the molecular mechanisms and pathophysiology of lymphedema and advances in tissue engineering technologies, lymphatic tissue bioengineering and regeneration have emerged as a potential therapeutic option for postsurgical lymphedema. Various strategies involving stem cells, lymphangiogenic factors, bioengineered matrices and mechanical stimuli allow more precisely controlled regeneration of lymphatic tissue at the site of lymphedema without subjecting patients to complications or iatrogenic injuries associated with surgeries. This review provides an overview of current innovative approaches of lymphatic tissue bioengineering that represent a promising treatment option for postsurgical lymphedema.

Advances and challenges in the treatment of esophageal cancer

Esophageal cancer (EC) is one of the most common cancers with high morbidity and mortality rates. EC includes two histological subtypes, namely esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). ESCC primarily occurs in East Asia, whereas EAC occurs in Western countries. The currently available treatment strategies for EC include surgery, chemotherapy, radiation therapy, molecular targeted therapy, and combinations thereof. However, the prognosis remains poor, and the overall five-year survival rate is very low. Therefore, achieving the goal of effective treatment remains challenging. In this review, we discuss the latest developments in chemotherapy and molecular targeted therapy for EC, and comprehensively analyze the application prospects and existing problems of immunotherapy. Collectively, this review aims to provide a better understanding of the currently available drugs through in-depth analysis, promote the development of new therapeutic agents, and eventually improve the treatment outcomes of patients with EC.

Cytokine-chemokine network driven metastasis in esophageal cancer; promising avenue for targeted therapy

Esophageal cancer (EC) is a disease often marked by aggressive growth and poor prognosis. Lack of targeted therapies, resistance to chemoradiation therapy, and distant metastases among patients with advanced disease account for the high mortality rate. The tumor microenvironment (TME) contains several cell types, including fibroblasts, immune cells, adipocytes, stromal proteins, and growth factors, which play a significant role in supporting the growth and aggressive behavior of cancer cells. The complex and dynamic interactions of the secreted cytokines, chemokines, growth factors, and their receptors mediate chronic inflammation and immunosuppressive TME favoring tumor progression, metastasis, and decreased response to therapy. The molecular changes in the TME are used as biological markers for diagnosis, prognosis, and response to treatment in patients. This review highlighted the novel insights into the understanding and functional impact of deregulated cytokines and chemokines in imparting aggressive EC, stressing the nature and therapeutic consequences of the cytokine-chemokine network. We also discuss cytokine-chemokine oncogenic potential by contributing to the Epithelial-Mesenchymal Transition (EMT), angiogenesis, immunosuppression, metastatic niche, and therapeutic resistance development. In addition, it discusses the wide range of changes and intracellular signaling pathways that occur in the TME. Overall, this is a relatively unexplored field that could provide crucial insights into tumor immunology and encourage the effective application of modulatory cytokine-chemokine therapy to EC.

Tandem post-synthetic modification of a zeolitic imidazolate framework for CXCR4-overexpressed esophageal squamous cell cancer imaging and therapy

Zeolitic imidazolate frameworks (ZIFs) as emerging porous materials have attracted remarkable attention for their unprecedented porosity and acidic sensitive degradation that enables high drug loading and microenvironment responsive fast payload release. However, the limited functions and disadvantages of ZIFs such as early drug release, potential cytotoxicity inducing damage to major organs, and even death of animals, impede their further biomedical application. In this work, we report the first tandem post-synthetic modification of ZIF-7 with both metal ions and organic ligands. Inspired by the benzimidazole-like inhibitors that are similar to the organic ligand of ZIF-7, a chemokine (C-X-C motif) receptor 4 (CXCR4) inhibitor AMD-070 (AMD) and magnesium ions (Mn²⁺) were successfully tandem exchanged to the ZIF-7 framework, forming an active-targeting framework AMD-ZIF-7(Mn) for CXCR4-overexpressed esophageal squamous cell cancer. The obtained AMD-ZIF-7(Mn) showed good biocompatibility in vitro and in vivo. Meanwhile, it exhibited an excellent T₁-weighted magnetic resonance imaging performance and CXCR4 targeting ability. With 5-Fu loading, AMD-ZIF-7(Mn)/5-Fu showed a synergistic therapeutic effect in DNA damage and CXCR4 inhibition of esophageal squamous cell cancer. Therefore, we propose a structural reconstruction method to effectively explore and improve the biomedical application of ZIFs in esophageal squamous cell cancer theranostics.

Expression levels of angiogenic growth factors in feline squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the skin in cats. Tumour angiogenesis is the pivotal event for tumour progression and metastasis. We assessed protein and gene expression of angiogenic growth factors including bFGF, VEGF-C, TGF-β, PDGF-A, PDGF-C and PDGFR-α that possibly contribute to the angiogenic phenotype of feline SCC (FSCC) and could, therefore, be a good target in the treatment of SCC. In the present study, a total of 27 FSCC cases were investigated. Tumour cases were histopathologically classified as well differentiated (10/27), moderately differentiated (5/27), and poorly differentiated (12/27). The expression levels of the growth factors were detected using immunohistochemistry and assessed semi-quantitatively. Growth factor expression levels were evaluated at different locations: in the oral region, in areas exposed to solar UV radiation including the ears, eyelids and nasal planum, and other miscellaneous locations. Our findings have revealed that FSCC arising from different anatomical sites of the body and showing differences in aggressiveness, metastasis, and prognosis may be angiogenesis dependent, and angiogenic key regulators could play a role in the development of FSCC.

Overexpression of VEGF-C and MMP-9 predicts poor prognosis in Kazakh patients with esophageal squamous cell carcinoma

Vascular endothelial growth factor (VEGF) and Matrix metalloproteinases (MMPs) are believed to participate in infiltration of tumors. High mortality of esophageal squamous cell carcinoma (ESCC) related to its primary infiltration; however, it is not clear whether the expression of VEGF and MMPs is involved in this process. Screening of The Cancer Genome Atlas (TCGA) database showed that among the VEGF family and MMP9, VEGF-A, VEGF-C, and MMP-9 mRNA were overexpression in ESCC. This result was verified using the Oncomine database and in Kazakh patients with ESCC. Overexpression of VEGF-C and MMP-9 and positive association with advanced esophageal cancer and invading ESCC cells (Gene Expression Omnibus (GEO): GSE21293). Immunohistochemical staining revealed that VEGF-C and MMP-9 were overexpressed in Kazakh ESCCs. VEGF-C expression was related to invasive depth, tumor-node-metastasis (TNM) staging, lymphatic, and lymph node metastasis of ESCC. The linear association between them was further confirmed in TCGA database and the specimens from Kazakh patients with ESCC. Patients with both proteins expression had tumors with greater aggressiveness, suffered from poor prognosis compared with patients who did not express either protein or expressed protein alone. Both proteins expression predicted high invasiveness of ESCC, which is related to worse prognosis of Kazakh ESCCs.

Effect of Ultrasound Combined With Microbubble Therapy on Interstitial Fluid Pressure and VX2 Tumor Structure in Rabbit

Interstitial fluid pressure (IFP) in tumor tissue is significantly higher than that in normal tissue, which reduces the effectiveness of therapeutic drugs. There are several methods to decrease the IFP, such as normalizing blood vessel, decreasing hyaluronic acid and collagen fiber content in the extracellular matrix (ECM), and recovering lymphatic function. Reducing tumor IFP might be developed as a novel approach in cancer therapy. In this study, we aimed to elucidate the relationship between ultrasound combined with microbubble therapy and IFP, and the associated mechanism. VX2 tumor in rabbit was treated with ultrasound combined with microbubbles at different intensities. The IFP was measured using the wick-in-needle (WIN) method. The collagen and reticular fibers were stained by Masson and Gordon-Sweets, respectively. The results showed that low-frequency non-focus ultrasound combined with microbubbles therapy influences the IFP in tumor tissues; low-frequency non-focus ultrasound with low pressure increased the IFP, whereas middle-high pressure decreased the IFP. The results showed that the structure and content of collagen and reticular fibers in tumor tissue were rarely influenced by the treatment. Our study provides a novel approach of reduced IFP antitumor therapy.

Significance of Angiogenic Growth Factors in Bovine Ocular Squamous Cell Carcinoma

Bovine ocular squamous cell carcinoma (BOSCC) is the most common and economically significant neoplasm of the eye in cattle. This study investigated the role of angiogenic growth factors in the pathogenesis of BOSCC. Eighteen cases of BOSCC were classified histopathologically according to the degree of differentiation. Normal upper and lower eyelids and third eyelids collected from the right and left eyes of six healthy cattle aged 1-3 years, that had been presented for slaughter to abattoirs, served as controls. Transcription of genes encoding the angiogenic growth factors vascular endothelial growth factor-C (VEGF-C), basic fibroblast growth factor (bFGF), platelet-derived growth factor-C (PDGF-C) and platelet-derived growth factor receptor-α (PDGFR-α) was determined by quantitative real-time polymerase chain reaction (RT-PCR) in tissue obtained from paraffin wax blocks. Immunohistochemistry (IHC) was utilized to detect intensity of expression and tissue distribution of these growth factors. IHC results revealed that bFGF and PDGF-C were elevated significantly (P >0.05) and VEGF-C expression was decreased in BOSCC compared with healthy control tissue. PDGR-α expression was elevated; however, the difference, compared with control tissues, was not significant. RT-PCR results showed an inverse relationship to the results of IHC; where protein levels were elevated their corresponding mRNA levels were decreased or vice-versa. Angiogenic regulators therefore appear to play a role in the pathogenesis of BOSCC.

Serum vascular endothelial growth factor-C levels predict lymph node metastasis and prognosis of patients with gallbladder cancer

Lymph node metastasis is the primary site of metastasis for patients with gallbladder cancer (GBC). Vascular endothelial growth factor-C (VEGF-C) has been implicated in the control of lymphangiogenesis and lymph node metastasis in various malignant tumors. However, the function of circulating VEGF-C is unclear and it is often difficult to evaluate lymph node metastasis and provide a prognosis for GBC. In the present study, ELISA was used to measure the preoperative serum VEGF-C (sVEGF-C) levels of 51 patients with GBC, 15 patients with chronic cholecystitis and 10 healthy volunteers. The results revealed a significantly increased sVEGF-C level in patients with GBC compared with the healthy donors, however no statistically significant difference was identified between patients with GBC and chronic cholecystitis. sVEGF-C levels were associated with lymph node metastasis in GBC and presented a positive correlation with VEGF-C expression and lymphatic vessel density (LVD) in patients with GBC. The mean survival time with high sVEGF-C was significantly reduced compared with low sVEGF-C. A similar result was also observed for VEGF-C expression and LVD. In summary, sVEGF-C levels may predict lymph node metastasis and the prognosis of patients with GBC.

Vascular endothelial growth factors C and D and lymphangiogenesis at the early stage of esophageal squamous cell carcinoma progression

We conducted a detailed study of lymphangiogenesis and subsequent lymph node metastasis in early-stage esophageal squamous cell carcinoma (ESCC) using immunostaining for D2-40 and vascular endothelial growth factor (VEGF)-C and D. The study materials included 13 samples of normal squamous epithelium, 6 samples of low-grade intraepithelial neoplasia (LGIN), and 60 samples of superficial ESCC (M1 and M2 cancer 24; M3 or deeper cancer 36). We assessed lymphatic vessel density (LVD) using D2-40 and immunoreactivity for VEGF-C and D in relation to histological type, lymphatic invasion, and lymph node metastasis. LVD in M1 and M2 lesions and M3 or deeper lesions was significantly higher than in normal squamous epithelium (P < 0.001). High expression of VEGF-C and D was observed in M1 and M2 cancer and in M3 or deeper cancer, but not in normal squamous epithelium or LGIN. LVD in VEGF-C- and D-positive cases was significantly higher than in negative cases (P < 0.001). In M3 or deeper cancer, the correlation between VEGF-C or D status and lymphatic invasion or lymph node metastasis was not significant. LVD in cases with positive lymphatic invasion and those with lymph node metastasis was significantly higher than in cases lacking either (P = 0.02 and 0.03, respectively). ESCC cells produce VEGF-C and D from the very early stage of progression. VEGF-C and D activate lymphangiogenesis, and this increase of lymphatic vessels leads to lymphatic invasion and subsequent lymph node metastasis.

Progranulin promotes lymphangiogenesis through VEGF-C and is an independent risk factor in human esophageal cancers

Lymph node metastasis is one of the most important predictors of the prognosis for esophageal cancer (EC) patients. However, the mechanism underlying the lymph node metastasis is largely unknown. Progranulin (PGRN) is shown to be highly expressed in various types of cancers and could promote the angiogenesis and epithelial-mesenchymal transition of cancer cells in previous studies. However, the expression status of PGRN and its effects on the lymphangiogenesis in EC are largely unclear. In this study, we show for the first time that PGRN is expressed in EC tissue samples and cell lines and could promote the expression of VEGF-C in vitro, a well-known lymphangiogenesis inducer, through the putative signaling transducers p-ERK and p-AKT. Besides, increased levels of PGRN are correlated with lymph node metastasis, high levels of lymph microvessel density, and lymph vessel space invasion in tissue samples of EC patients. In addition, Cox proportional risk model shows that patients with high levels of PGRN would have 2-fold increases in 5-year mortality compared with patients with low levels of PGRN. Finally, we establish a clinically useful nomogram to predict the possibility of mortality for individual EC patients. In conclusion, PGRN may play an important role in the lymphangiogenesis through activation of VEGF-C in the EC patients.

Glucose-regulated protein 94 mediates progression and metastasis of esophageal squamous cell carcinoma via mitochondrial function and the NF-kB/COX-2/VEGF axis

Esophageal cancer is a worldwide health problem with a very poor prognosis. Therefore, new diagnostic biomarkers or therapeutic strategies for identifying and managing esophageal squamous cell carcinoma (ESCC) are urgently needed. Glucose-regulated protein 94 (GRP94) is one of major endoplasmic reticulum-stress response proteins that plays a key role in cancer progression and therapeutic responses. However, the role of GRP94 in ESCC progression and metastasis remains unclear. The tissue array results indicated that higher GRP94 expression levels were associated with lower overall survival and higher lympho-node metastasis. Silencing GRP94 (GRP94-KD) reduced cell proliferation, migration and invasion in ESCC cells. In a xenotransplantation assay, silencing GRP94 reduced cell proliferation in the zebrafish embryo. Transmission electron microscopy revealed impaired mitochondria in GRP94-KD cells, which exhibited reduced basal respiration, spare respiratory capacity and ATP production and increased oxidative damage compared with scrambled control cells. Regarding the molecular mechanism underlying the effects of GRP94 knockdown, we found that silencing GRP94 may reduce the level of NF-kB, c-Jun, p38, IL-6, vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) as well as activation of AKT and ERK. In conclusion, our results indicate that silencing GRP94 in ESCC cells suppressed cancer growth and the metastatic potential via mitochondrial functions and NF-kB/COX-2/VEGF in ESCC cells.

Structural alterations in tumor-draining lymph nodes before papillary thyroid carcinoma metastasis

BACKGROUND

The purpose of this study was to define and characterize the thyroid tumor-draining lymph nodes in genetically engineered mice harboring thyroid-specific expression of oncogenic Braf^V600E with and without Pten insufficiency.

METHODS

After intratumoral injection of methylene blue, the lymphatic drainage of the thyroid gland was visualized in real time. The thyroid gland/tumor was resected en bloc with the respiratory system for histological analysis.

RESULTS

Although mice harboring Braf^V600E mutations were smaller in body size compared with their wild-type (WT) littermates, the size of their thyroid glands and deep cervical lymph nodes were significantly larger. Additionally, the tumor-draining lymph nodes showed increased and enlarged lymphatic sinuses that were distributed throughout the cortex and medulla. Tumor-reactive lymphadenopathy and histiocytosis, but no frank metastases, were observed in all mice harboring Braf^V600E mutations.

CONCLUSIONS

The tumor-draining lymph nodes undergo significant structural alterations in immunocompetent mice, and this may represent a primer for papillary thyroid carcinoma (PTC) metastasis.

Use of NRP1, a novel biomarker, along with VEGF-C, VEGFR-3, CCR7 and SEMA3E, to predict lymph node metastasis in squamous cell carcinoma of the tongue

Lymph node (LN) metastasis has been suggested as a major prognostic factor for oral cancer. Knockdown of the growth factors and receptors involved in these metastatic mechanisms could significantly reduce LN metastasis and improve the survival of oral cancer patients after treatment. The present study, therefore, aimed to evaluate the expression levels of the following growth factors and receptors in squamous cell carcinoma (SCC) of the tongue: the vascular endothelial growth factor (VEGF)‑C and VEGF‑D, which bind to the cell surface tyrosine kinase receptor VEGF receptor‑3 (VEGFR‑3); C‑C motif chemokine receptor 7 (CCR7); neuropilin (NRP)1 and NRP2; and semaphorin 3E (SEMA3E). Furthermore, we assessed microvessel density (MVD) and lymphatic vessel density (LVD) to demonstrate the correlation between these factors and regional LN metastasis, with respect to the clinicopathological features. Finally, we analyzed the correlation between these proteins and overall or disease‑free survival, in order to demonstrate their prognostic value. Univariate analysis revealed a significant association between LN metastasis and the expression levels of VEGF‑C, VEGFR‑3, CCR7, NRP1, and SEMA3E, as well as LVD, in SCC cells. In contrast, multivariate analysis identified associations between LN metastasis and NRP1 expression, as well as between LN metastasis and LVD; however, no correlation was found between LN metastasis and the expression levels of the other proteins. The expression levels of VEGF‑C, VEGFR‑3, NRP1, and SEMA3E, as well as LVD, were correlated with disease‑free survival time. These results indicate that LN metastasis is associated with poor survival in SCC. This study suggests that NRP1 expression and LVD are independent factors that are likely to predict the risk of LN metastasis in SCC of the tongue, whereas the expression of VEGF‑C, VEGFR‑3, CCR7, and SEMA3E are non‑independent predictive factors.

A single dividing cell population with imbalanced fate drives oesophageal tumour growth

Understanding the cellular mechanisms of tumour growth is key for designing rational anticancer treatment. Here we used genetic lineage tracing to quantify cell behaviour during neoplastic transformation in a model of oesophageal carcinogenesis. We found that cell behaviour was convergent across premalignant tumours, which contained a single proliferating cell population. The rate of cell division was not significantly different in the lesions and the surrounding epithelium. However, dividing tumour cells had a uniform, small bias in cell fate so that, on average, slightly more dividing than non-dividing daughter cells were generated at each round of cell division. In invasive cancers induced by Kras(G12D) expression, dividing cell fate became more strongly biased towards producing dividing over non-dividing cells in a subset of clones. These observations argue that agents that restore the balance of cell fate may prove effective in checking tumour growth, whereas those targeting cycling cells may show little selectivity.

RASSF8 downregulation promotes lymphangiogenesis and metastasis in esophageal squamous cell carcinoma

Lymphatic vessels are the major routes of human esophageal squamous cell carcinoma (ESCC) metastasis. Tumor cells secrete pro-lymphangiogenic factors to induce new lymphatic vessels, promoting lymph node metastasis. In this study, we show that RAS association domain family 8 (RASSF8) expression in ESCC clinical samples was inversely correlated with lymph node metastasis and patients survival. Tumor cells with low RASSF8 expression had higher apparent migratory ability, and promoted and lymphangiogenesis both in vitro and in vivo. RASSF8 downregulation enhanced VEGF-C expression and caused subcellular redistribution of p65 in ESCC. Our results show that RASSF8 acts as a tumor suppressor in ESCC and is a potential therapeutic target for preventing lymph node metastasis.

Association between VEGF-A, C and D expression and lymph node involvement in breast cancer: a meta-analysis

BACKGROUND

Metastasis is the primary cause of death in patients with breast cancer. Although VEGF-A, C and D are considered to be prime factors in lymph node metastasis in breast cancer, the published studies have conflicting conclusions.

METHODS

To resolve this conflict, we conducted a meta-analysis of 37 studies (n = 5,001 patients) evaluating the correlation between VEGF-A, C and D immunohistochemical expression and lymph node metastasis (LNM). The meta-analysis included 22 studies of VEGF-A, 17 of VEGF-C, and 6 of VEGF-D. The relationships between VEGF-A, C and D and clinicopathological parameters were also examined.

RESULTS

The results showed a significant association between VEGF-A or VEGF-C overexpression and LNM (risk ratio [RR] = 1.28 [95% CI 1.04-1.58], p = 0.02; and RR = 1.36 [95% CI 1.07-1.72], p = 0.01, respectively). Subgroup evaluation showed a significant association between VEGF-A, C and D overexpression and LNM when analyses were limited to Asian patients (RR = 1.78 [95% CI 1.28-2.46], p = 0.0005; RR = 1.38 [95% CI 1.04-1.84], p = 0.03, and RR = 2.62 [95% CI 1.35-5.09], p = 0.004, respectively). VEGF-A overexpression was significantly associated with lymph vessel invasion (RR = 1.86 [95% CI 1.33-2.60], p = 0.0003). Overexpression of VEGF-C or VEGF-D was significantly associated with HER-2 positivity (RR = 1.30 [95% CI 1.06-1.59], p = 0.01; and RR = 1.75 [95% CI 1.01-3.03], p = 0.05, respectively).

CONCLUSIONS

With some limitations, our meta-analysis indicated that VEGF-A and C could predict LNM in patients with breast cancer, particularly Asian patients.

Association between vascular endothelial growth factor expression and lymph node metastasis in cervical cancer: A meta-analysis

AIM

The expression of vascular endothelial growth factor (VEGF) by cancer cells has been identified as a factor that is associated with lymph node metastasis (LNM) in some cancers, but an accurate description of the relation between VEGF and LNM in cervical cancer is lacking. We conducted a concurrent meta-analysis to investigate this issue.

METHODS

We searched PubMed and EMBASE for articles addressing the association between VEGF and cervical cancer. We used stata 12.0 and calculated the crude odds ratios (OR) and corresponding 95% confidence intervals (CI). Heterogeneity between the studies included was assessed by Cochran's Q-test.

RESULTS

Overall, 16 relevant studies with 426 cases and 751 controls were included in our study. The results demonstrated that cervical cancer patients with VEGF-positive expression had a 2.87-fold higher risk of LNM than patients without VEGF-positive expression (95%CI = 1.85-4.44, P < 0.001). Furthermore, subgroup analysis by ethnicity revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Asian populations (OR = 2.55, 95%CI = 1.61-4.03, P < 0.001) and Caucasian populations (OR = 8.81, 95%CI = 2.78-27.88, P < 0.001). Moreover, subgroup analysis by country revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Chinese populations (OR = 3.38, 95%CI = 2.18-5.25, P < 0.001) but not among Korean populations (P = 0.84) or Japanese populations (P = 0.06). Subgroup analysis based on sample size proved that VEGF-positive expression was statistically associated with LNM in a large sample group.

CONCLUSION

Our study revealed that VEGF-positive expression is related with higher risk of LNM in cervical cancer.

The relationship between the expression of VEGF, EGFR, and HER-2 mRNA in esophageal squamous cell carcinoma (ESCC) and clinicopathological features of different ethnic groups in Xinjiang

The purpose of this study was to explore the relationship between the expression of vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (HER-2), and epidermal growth factor receptor (EGFR) mRNA in esophageal squamous cell carcinoma (ESCC) and the clinicopathological characteristics of the Han, Uyghur, and Kazakh in Xinjiang. Real-time quantitative polymerase chain reaction technology (RT-PCR) was used to detect the expression of VEGF, HER-2, and EGFR mRNA in esophageal squamous cancer tissue of 60 cases and 30 cases of VEGF, HER-2, and EGFR mRNA in esophageal cancer adjacent tissues, and analyze its relationship with clinicopathological features. The results were as follows: (1) There was no statistically significant difference in esophageal tissue VEGF, HER-2, and EGFR mRNA gene expression levels of the Han, Uyghur, and Kazakh patients (P > 0.05). (2) The expression levels of VEGF, HER-2, and EGFR mRNA in ESCC group were higher than those in adjacent esophageal tissue group (P < 0.05). (3) The expression levels of VEGF and HER-2 mRNA in ESCC of the Han patients were higher than those of the Uyghur and Kazakh patients (P < 0.05). (4) The expression levels of VEGF, HER-2, and EGFR mRNA in lymph node metastases were higher than those without lymph node metastasis (P < 0.05). (5) The expression level of HER-2 mRNA was related with the degrees of pathological differentiation, and the higher pathologic degree, the lower expression level in HER-2 mRNA (P < 0.05). Therefore, the following conclusions were drawn: (1) There were ethnic differences in the VEGF and HER-2 gene mRNA expression levels of the Uyghur, Han, and Kazakh patients in Xinjiang. (2) The expressions of VEGF, HER-2, and EGFR mRNA were related to the lymph node metastasis in ESCC and pathologic differentiation degree.

Prognostic value of vascular endothelial growth factor-C and podoplanin mRNA expression in esophageal cancer

Vascular endothelial growth factor-C (VEGF-C), VEGF-D, VEGF receptor-3 (VEGFR-3) and podoplanin (PDPN) are involved in the spread of cancer. The current study evaluated VEGF-C, VEGF-D, VEGFR-3 and PDPN mRNA expression levels in 84 esophageal cancer samples from patients who had undergone surgery according to reverse transcription-quantitative polymerase chain reaction, and correlated the results with the clinicopathological features. The effects on lymph node metastasis and survival were identified by performing univariate and multivariate analyses. VEGF-C, PDPN, VEGF-D and VEGFR-3 were overexpressed in 52.4, 52.4, 32.1 and 51.2% of esophageal cancer samples, respectively. Furthermore, the expression of VEGF-C and PDPN was significantly correlated with lymph node metastasis, depth of tumor invasion and tumor stage (P<0.05). Logistic regression analysis identified tumor size (P=0.001), depth of invasion (P=0.002) and PDPN mRNA expression (P=0.022) as significant multivariable predictors of regional lymph node metastasis. Upon univariate survival analysis, the depth of tumor invasion, lymph node metastasis, histological grade, tumor stage, tumor size, residual tumor, and VEGF-C and PDPN mRNA expression were identified to be significant independent prognostic factors for overall survival (OS) time. Additionally, multivariate analysis identified tumor size (P=0.049), residual tumor (P<0.001) and PDPN mRNA expression (P=0.02) as independent factors for poor OS time. Thus, it was concluded that PDPN mRNA expression may serve as predictor for regional lymph node metastasis, and that VEGF-C and PDPN may be prognostic factors in patients with resected esophageal cancer.

Immunohistochemical study of vascular endothelial growth factor-C/vascular endothelial growth factor receptor-3 expression in oral tongue squamous cell carcinoma: Correlation with the induction of lymphangiogenesis

The aim of the present study was to elucidate the associations between the expression of the vascular endothelial growth factor-C (VEGF-C)/VEGF receptor-3 (VEGFR-3) axis and lymphangiogenesis, regional lymph node metastasis and clinicopathological factors in oral tongue squamous cell carcinoma (OTSCC) using immunohistochemistry. The expression of VEGF-C, VEGFR-3 and podoplanin was immunohistochemically evaluated in specimens obtained from 65 patients with OTSCC (T1-2, N0) who had undergone radical surgery alone. The associations between the expression of VEGF-C, VEGFR-3 and podoplanin, and lymphangiogenesis, regional lymph node metastasis and clinocopathological factors were determined by immunohistochemical analysis. VEGF-C, VEGFR-3 and combined VEGF-C/VEGFR-3 expression was significantly higher in cases with regional recurrence compared with those without lymph node involvement (P<0.001). As regards lymphangiogenesis, a significant correlation was observed between podoplanin expression and VEGF-C, VEGFR-3 and combined VEGF-C/VEGFR-3 expression (P<0.001). Therefore, lymphangiogenesis in the peritumoral stroma was associated with lymph node metastasis. However, podoplanin expression did not exhibit a significant correlation with the progression of lymph node metastasis. The results of the present study suggest that the VEGF-C/VEGFR-3 axis may be associated with lymph node metastasis through lymphangiogenesis. Determining the VEGF-C/VEGFR-3 expression status may help predict which patients will develop regional recurrence and provide novel targets for therapies to suppress lymph node metastasis in the treatment of OTSCC.

Vascular endothelial growth factor-C expression as a biomarker of poor prognosis in esophageal squamous cell carcinoma: a meta-analysis

BACKGROUND

Vascular endothelial growth factor C (VEGF-C) is involved in the development and progression of tumor angio-/lymphangiogenesis. The purpose of this study is to evaluate whether VEGF-C expression is an indicator of aggressiveness and poor prognosis of esophageal squamous cell carcinoma (ESCC).

METHOD

A meta-analysis was conducted to investigate the association between VEGF-C expression with clinicopathological characteristics and survival of ESCC patients. The dataset was defined by searching PubMed, Embase, Google Scholar, and the Cochrane database for appropriate articles published until April 2014.

RESULT

The final analysis was made from 9 studies, including 656 ESCC patients. Positive VEGF-C expression was defined by immunohistochemistry (IHC) or mRNA expression analysis. The results demonstrated that VEGF-C expression was significantly associated with advanced-stage disease (odds ratio (OR) = 2.29, 95% confidence interval (CI) = 1.37-3.84, P = 0.002), deeper tumor invasion, lymph node metastasis, and lymphatic invasion. The 5-year survival of VEGF-C expression-negative patients was found to be better than that of VEGF-C expression-positive patients (OR = 0.35, 95% CI = 0.21-0.58, P < 0.0001). However, there was no significant association between the VEGF-C expression levels and either poorer tumor differentiation or vascular invasion.

CONCLUSION

The results of the meta-analysis strongly indicate that VEGF-C expression could function as a marker for predicting the aggressiveness and prognosis of ESCC.

Current opinion on bevacizumab on endometrial cancer treatment

INTRODUCTION

Advanced or recurrent endometrial cancer is still a challenge for clinicians as it has a poor prognosis despite treatment efforts. Thus, there is an urgent need for new agents with activity in this subset of patients. The increased knowledge of the molecular aspects of endometrial carcinogenesis has led to the development of molecular targeted therapies and in particular anti-angiogenic drugs. One of the most promising of these agents is bevacizumab , a recombinant humanized immunoglobulin monoclonal antibody to VEGF.

AREAS COVERED

The objective of this paper is to discuss the role of angiogenesis in endometrial cancer and analyze the rational of bevacizumab use, alone or in combination with other therapies, in endometrial cancer patients. We reviewed the most important preclinical and clinical studies published on this topic up to March 2014.

EXPERT OPINION

Bevacizumab in combination with others targeted therapies, chemotherapy or radiotherapy demonstrated promising anti-tumor activity. Despite the good oncological outcomes of these recent clinical experiences, caution must be used in light of significant toxicity reported in this subset of heavily pre-treated patients. The identification of biomarkers able to predict either the efficacy or toxicity of anti-angiogenic drugs is a compelling need.

Expression levels of vascular endothelial growth factors a and C in patients with peptic ulcers and gastric cancer

Purpose

Vascular endothelial growth factor (VEGF) is one of the most important growth factors for metastatic tumors. To clarify the role of VEGF-A and C in patients with peptic ulcer disease (PUD) or gastric cancer (GC), we evaluated the expression levels of these two molecules. We also analyzed the effect of Helicobacter pylori infection on VEGF-A and C expression levels.

Materials and Methods

Patients with dyspepsia who needed diagnostic endoscopy were selected and divided into three groups: non-ulcer dyspepsia (NUD), PUD, and GC, according to their endoscopic and histopathological results. Fifty-two patients with NUD, 50 with PUD, and 38 with GC were enrolled in this study. H. pylori infection was diagnosed by the rapid urease test. After RNA extraction and synthesis of cDNA, the expression levels of VEGF-A and C were determined by quantitative reverse transcriptase polymerase chain reaction.

Results

The VEGF-C expression level in the PUD and GC groups was significantly higher than that in the NUD group. Moreover, the VEGF-A expression level in the PUD and GC groups was higher than in the NUD group, although the differences were not statistically significant. Significant positive correlations were also observed between the expression levels of these two molecules in the PUD and GC groups. In addition, the expression levels of these two molecules were higher in H. pylori positive patients with PUD or GC than in H. pylori negative patients of the same groups; however, these differences did not reach statistical significance.

Conclusions

Up-regulation of VEGF-C expression during gastric mucosal inflammation may play a role in the development of peptic ulcers or GC.

SIRT1 expression is associated with lymphangiogenesis, lymphovascular invasion and prognosis in pN0 esophageal squamous cell carcinoma

Background

Sirtuin1 (SIRT1) is an NAD⁺-dependent type III histone deacetylase (HDAC). This research investigated the prevalence of SIRT1 protein expression and its prognostic influence with the aim of validating its potential role in lymphangiogenesis and lymphovascular invasion (LVI) in pN0 esophageal squamous cell carcinoma (ESCC).

Methods

A total of 206 patients were enrolled in this retrospective study. SIRT1 and VEGF-C protein expression was detected by immunohistochemical staining. Peritumoral lymphatic microvessel density (LVD) and LVI were evaluated by immunostaining for D2-40. Statistical analysis was then preformed to investigate the relevance of SIRT1 expression and various clinicopathologic features and to examine the effect of SIRT1 on tumor-induced lymphangiogenesis, LVI and prognosis.

Results

SIRT1 positive expression was identified in 95 cases in the nucleus and was significantly correlated with T status (P < 0.001), disease stage (P = 0.001), VEGF-C positive expression (P = 0.015), high LVD (P = 0.013) and positive LVI (P = 0.015). Patients with SIRT1 positive expression, high LVD and positive LVI had a significantly unfavorable 5-year disease free survival (P < 0.001, P = 0.030, and P < 0.001, respectively) and overall survival (P < 0.001, P = 0.017, and P < 0.001, respectively). However, based on multivariate Cox regression analysis, only SIRT1 positive expression and positive LVI were significant independent prognosticators of poor disease-free survival (P = 0.029 and 0.018, respectively) and overall survival (P = 0.045 and 0.031, respectively).

Conclusions

SIRT1 positive expression was significantly associated with tumor progression, lymphangiogenesis, LVI and poor survival in pN0 ESCC patients. Our research shows a utilization of SIRT1 in prognosing poor survival and providing possible target for ESCC patients through inhibiting its lymphangiogenesis activity.

Expressions of D2-40, CK19, galectin-3, VEGF and EGFR in papillary thyroid carcinoma

OBJECTIVE

To investigate the expressions of D2-40, CK19, galectin-3, VEGF, and EGFR in papillary thyroid carcinoma and their clinical significances.

METHODS

The expressions of D2-40, CK19, galectin-3, VEGF, and EGFR in 38 cases of papillary thyroid carcinoma and 12 cases of thyroid papillary hyperplasia were detected by immunohistochemical staining.

RESULTS

The positive expression rates of D2-40, CK19, Galectin-3, VEGF and EGFR in patients with papillary thyroid carcinoma were all significantly higher than those in patients with thyroid papillary hyperplasia (all P<0.05). The expressions of D2-40, VEGF, and EGFR in papillary thyroid carcinoma with lymph node metastasis were significantly higher than those without lymph node metastasis (P<0.05). The expressions of GK19 and galectin-3 showed no significant differences between the papillary thyroid carcinomas with and without lymph node metastasis (P>0.05).

CONCLUSIONS

The detection of D2-40, CK19, galectin-3, VEGF, and EGFR is helpful for the diagnosis and differential diagnosis of papillary thyroid carcinoma and thyroid papillary hyperplasia.

Cytokines association with clinical and pathological changes in esophageal squamous cell carcinoma

Carcinogenic transformation of cells in esophageal squamous cell carcinoma (ESCC) is characterized on molecular level by, among other things, changes in protein expression. Among all proteins related to inflammation, cytokines may be implicated as possible biological markers of esophageal cancer. These biomarkers, near imaging techniques, may be helpful in diagnosis and monitoring therapy in ESCC patients. This review demonstrates findings of researches on dysregulation of cytokines in ESCC and their clinical and pathological implications. Articles on cytokines were selected according to the following criteria: (i) the study was performed at protein level, (ii) the differences in cytokines expression or concentration were detected in tissues or serum from ESCC patients, (iii) the alterations of cytokines levels were detected by: immunohistochemistry (IHC), western blot (WB) and enzyme-linked immunosorbent assay (ELISA). Members of VEGF family seem to play an essential role as potential markers in ESCC. The results of all cytokines researches are promising but further studies are necessary to establish the biological significance of these peptydes in ESCC, their potential usefulness for early diagnosis, pre- and postoperative prognosis and monitoring of the respond to chemo- and radiotherapy of cancer patients.

Metastasis via Peritumoral Lymphatic Dilation in Oral Squamous Cell Carcinoma

PURPOSE

Nodal metastasis is the main prognostic factor in the patients with oral squamous cell carcinoma (OSCC). We investigated the association between tumor-associated lymphatics and OSCC characteristics.

METHODS

Thirty-four specimens were used for the immunohistochemical staining with the antibody for vascular endothelial growth factor (VEGF)-C, VEGF-D, VEGF receptor (VEGFR)-3, phosphorylated VEGFR-3, D2-40, and matrix metallproteinases (MMPs). We observed the distribution of the lymphangiogenic factors and quantified the degree of expression. We determined lymphatic vessel density (LVD) and lymphatic vessel dilatation with D2-40 immunostaining. We assessed the association of LVD or lymphatic vessel dilatation with tumor progression or tumor differentiation.

RESULTS

OSCC cells expressed lymphangiogenic ligands. Lymphangiogenic receptor, VEGFR-3, was expressed and activated in some tumor cells as well as in tumor-associated endothelial cells. LVD was not associated with tumor size or nodal status, but lymphatic vessel dilatation was higher in tumors with nodal metastasis, and also higher in poorly differentiated tumors. In stromal area of OSCC, MMP-1 and MMP-10 were up-regulated and the basement membrane of tumor-associated endothelial cells was destroyed by these collagenases.

CONCLUSION

In the primary tumors with nodal metastasis, especially in poorly differentiated OSCC, tumor cells invaded the dilated lymphatic vessels via ruptured sites. MMP-1 and MMP-10 are important in the lysis of the glycocalyx inside the tumor-associated lymphatic endothelial cells.

Homologous mesenchymal stem cells promote the emergence and growth of pulmonary metastases of the rat osteosarcoma cell line UMR-106

Osteosarcoma (OS) is the most frequent primary bone sarcoma and tends to develop pulmonary metastasis. Studies have shown that mesenchymal stem cells (MSCs) are involved in OS growth and metastasis, but the mechanism remains unclear. The aim of the present study was to identify whether homologous MSCs could promote the growth and metastasis of OS in rats with a normal immune system. The OS cell line, UMR-106, which originally derives from a Sprague-Dawley (SD) rat-transplantable osteogenic sarcoma with an osteoblastic phenotype, has a strong carcinogenic capability and a high lung metastasis. Xenotransplanted models of UMR-106 with or without MSCs injected through the tibia (IT) or caudal vein (IV) were established. SD rats were randomly divided into six groups: Control, UMR-106 (IT), MSCs (IV), UMR-106 (IT) + MSCs (IV), UMR-106 (IV) and UMR-106 (IV) + MSCs (IV). Following injection, all rats were sacrificed at week 5, and the volume and quantity of metastatic sarcoma and the serum alkaline phosphatase levels were measured. There was no metastatic sarcoma in the liver, spleen and kidney in all groups. The rats in the MSCs (IV) + UMR-106 (IV) group showed a significantly higher volume and number of pulmonary metastatic tumors than those of the UMR-106 (IV) group. In pulmonary metastatic tissues, MSCs were found in the MSCs (IV) + UMR-106 (IV) group, but not in the UMR-106 (IT) + MSCs (IV) group. Notably, the expression of vascular endothelial growth factor (VEGF) was increased in the MSCs + UMR-106 cells co-culture system. The present study indicated that MSCs can significantly promote the pulmonary metastasis of the rat OS cell line, UMR-106, with a normal immune system, and VEGF was involved in MSC-promoted UMR-106 emergence and growth of pulmonary metastasis.

Neither expression of VEGF-C/D nor lymph vessel density supports lymphatic invasion as the mechanism responsible for local spread of recurrent salivary pleomorphic adenoma

Recent research suggests that multinodular recurrent pleomorphic adenoma (PA) might result from cell migration through lymphatics. Lymphangiogenesis in malignancies is mediated by vascular endothelial growth factors C and D (VEGF-C/D). We studied the expression of VEGF-C/D in PA by immunohistochemistry as well as lymphatic vessel density (LVD). In 6 non-recurrent, 4 primary-to-recur, and 10 recurrent PAs, VEGF-C/D expression was assessed by immunohistochemistry. Staining was scored in terms of staining intensity (0 = absent to 3 = strong), and the percentage of positive tumor cells (scored as 0 (0-19 %), 1 (20-39 %), 2 (40-50 %), and 3 (60-100 %)) and a sum score were calculated. Intra- and peritumoral LVD was assessed by counting of LV after immunostaining, using the D2-40 antibody. All but one sample were VEGF-C negative. The differences in VEGF-D expression between non-recurrent, primary-to-recur, and recurrent PAs were not significant (p>0.05). VEGF-D expression did not correlate with peritumoral LVD (p>0.05). Our study revealed a significant difference between intra- and peritumoral LVD values when comparing individual and all sample groups (p=0.01). The lack of VEGF-C expression and of significant differences in VEGF-D expression and peritumoral LVD between patients with non-recurrent, primary-to-recur, and recurrent PAs does not support the lymphangiogenic local spread hypothesis

Expression of vascular endothelial growth factor-C and vascular endothelial growth factor receptor-3 in esophageal squamous cell carcinoma

Lymph node metastasis is one of the most important prognostic factors in esophageal squamous cell carcinoma (ESCC). Vascular endothelial growth factor (VEGF)-C and its receptor, VEGF receptor-3 (VEGFR-3), are key in the process of lymphangiogenesis. The present study immunohistochemically examined the expression of VEGF-C, VEGFR-3 and D2-40 in 119 patients with ESCC, and microlymphatic vessel density (MLVD) was calculated based on D2-40 expression counts. Positive expression of VEGF-C was found to correlate significantly with depth of tumor invasion, lymphatic invasion and lymph node metastasis (P<0.001, P<0.0001 and P<0.0001, respectively). Patients with deeper tumor invasion showed higher positivity of VEGFR-3 expression (P<0.05), while patients with lymph node metastasis showed higher MLVD (P<0.05). When patients were divided into three groups according to the expression of VEGF-C and VEGFR-3, patients with coexpression of VEGF-C and VEGFR-3 exhibited poorer prognosis and higher MLVD. The VEGF-C/VEGFR-3 axis is important in tumor lymphangiogenesis.

Double-positive expression of high-mobility group box 1 and vascular endothelial growth factor C indicates a poorer prognosis in gastric cancer patients

Background

Although many studies have indicated that high-mobility group box 1 protein (HMGB1) is associated with oncogenesis and a worse prognosis, the prognostic value of HMGB1 in gastric cancer (GC) remains unclear. In the present work, we aimed to evaluate the role of HMGB1 in GC and examined whether aberrant expression of both HMGB1 and vascular endothelial growth factor C (VEGF-C) increased the malignant potential of GC.

Methods

A total of 166 GC patients and 32 normal subjects were enrolled. HMGB1 and VEGF-C expression was detected by tissue microarrays (TMAs) and immunohistochemical staining. The correlation between HMGB1 and VEGF-C expression and their relationships with clinicopathological GC variables were examined. Univariate and multivariate analyses were performed using the Cox proportional hazard model to predict the factors related to the patients‘ overall survival rates.

Results

HMGB1 and VEGF-C expression were observed in 81 (48.80%) and 88 (53.01%) tumors, respectively, significantly higher than the rates among the corresponding controls. In addition, HMGB1 and VEGF-C expression were positively correlated (R² = 0.972). HMGB1 expression was also closely associated with tumor size, pT stage, nodal status, metastasis status, TNM stage, and poor prognosis. Multivariate survival analysis indicated that patients with HMGB1 and VEGF-C coexpression had the worst prognoses and survival rates (hazard ratio, 2.78; log rank P<0.001).

Conclusions

HMGB1 is commonly expressed in GC. Combined evaluation of HMGB1 and VEGF-C may serve as a valuable independent prognostic factor for GC patients.

Quantitative analysis of VEGF-C mRNA of extrahepatic cholangiocarcinoma with real-time PCR using samples obtained during endoscopic retrograde cholangiopancreatography

OBJECTIVE

Vascular endothelial growth factor (VEGF)-C overexpression in extrahepatic cholangiocarcinoma (ECC) has been shown to be correlated with lymph node metastasis. The intensity of immunohistochemical staining of VEGF-C protein in surgical samples has been used as index of VEGF-C overexpression in previous studies. The aim of the study was to examine if VEGF-C overexpression in ECC could be preoperatively detected by using samples obtained during ERCP.

METHODS

Consecutive patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for biliary stricture during the study period were prospectively analyzed. VEGF-C mRNA was quantified by real-time PCR methods using endoscopic samples obtained during ERCP. The high intensity of immunohistochemical staining of VEGF-C protein in surgical samples was used for the reference standard of VEGF-C overexpression. The level of S100P mRNA which was a novel diagnostic marker of ECC was also quantified to evaluate whether the endoscopic samples contained ECC cells.

RESULTS

Twenty-five patients were enrolled in this study. Eighteen patients were diagnosed as ECC and seven patients were diagnosed as benign biliary structure. Nine of eighteen patients with ECC, who showed positive S100P mRNA in endoscopic samples and received surgical resection, were finally analyzed. Receiver operating characteristics analysis yielded VEGF-C mRNA cut-off value of 3.85 for detection of VEGF-C overexpression, and the diagnostic performance of VEGF-C mRNA measurement in the endoscopic sample for VEGF-C overexpression reached sensitivity of 75.0%, specificity of 100%, and accuracy of 88.9%.

CONCLUSION

The quantification of VEGF-C mRNA of ECC with real-time PCR using endoscopic samples was useful for preoperative detection of VEGF-C overexpression.

Cyclo-oxygenase-2 expression is associated with vascular endothelial growth factor C expression and lymph node metastasis in oral squamous cell carcinoma

PURPOSE

Cervical lymph node metastasis in oral squamous cell carcinoma (OSCC) is recognized as a poor prognostic factor, although its mechanism remains unclear. Recently, cyclo-oxygenase-2 (COX-2) level has been found to correlate highly with vascular endothelial growth factor C (VEGF-C) and lymph node metastasis, as in other solid tumors. However, there has been no report of this correlation in OSCC. Therefore, the aim of this study was to investigate whether COX-2 immunohistochemical expression in OSCC was associated with VEGF-C expression, histopathologic parameters, and lymph node metastasis.

MATERIALS AND METHODS

Lymphatic vessel density, VEGF-C, and COX-2 immunohistochemical expression were examined pathologically in 60 specimens of invasive OSCC. Relations of histopathologic parameters to lymph node metastasis were analyzed.

RESULTS

Expression levels of VEGF-C and COX-2 and lymphatic vessel density in the lymph node metastatic group were significantly higher than in the nonmetastatic group (P < .01). A significant correlation was found between the expression levels of VEGF-C and COX-2 (r = 0.512; P < .001). COX-2 expression was significantly related to lymph node metastasis (P = .004) and VEGF-C expression (P = .005). Univariate analysis showed that survival time was impaired by higher COX-2 and VEGF-C expression levels. Multivariate survival analysis showed that COX-2 expression was an independent prognostic factor.

CONCLUSION

This study showed that VEGF-C expression was upregulated by COX-2 in OSCC. High VEGF-C expression appears to promote peritumoral lymphangiogenesis. These data indicated that lymph node metastasis is promoted by COX-2 and VEGF-C in OSCC.

Expression and significances of contactin-1 in human gastric cancer

Background. This study aimed at determining the relationship between vascular endothelial growth factor-C (VEGF-C), vascular endothelial growth factor receptor-3 (VEGFR-3), and contactin-1 (CNTN-1) expression in gastric cancer (GC). Methods. The expression level of CNTN-1 mRNA and CNTN-1 protein of 33 cases was determined using RT-PCR and Western Blot. And 105 cases were immunohistochemically examined for VEGF-C, VEGFR-3, and CNTN-1 expressions. Assessment of lymphatic vessel density (LVD) was also performed by D2-40 immunostaining. Then we analyzed the relationships between VEGF-C, VEGFR-3, and CNTN-1, as well as their correlations with clinicopathologic features, LVD, and survival time. Results. The positivity rate of VEGF-C, VEGFR-3, and CNTN-1 in primary tumor was 56.19%, 64.76%, and 58.09%. The expression of CNTN-1 significantly correlated with VEGF-C (P < 0.001) and VEGFR-3 (P < 0.001). All of them were closely related to TNM stage, lymphatic invasion, and lymph node involvement (P < 0.05). LVD was significantly correlated with VEGF-C (P = 0.001), VEGFR-3 (P = 0.011), and CNTN-1 expression (P < 0.001). VEGF-C, VEGFR-3, and CNTN-1 expression significantly associated with poorer prognosis (P < 0.001, P = 0.034, P = 0.012, resp.). Conclusion. CNTN-1 associated with VEGF-C and VEGFR-3 expression in GC. All of them correlated with lymphatic metastasis, which might play an important role in the lymphatic invasion via lymphangiogenesis pathway in GC.

Lymphatics in lymphangioleiomyomatosis and idiopathic pulmonary fibrosis

The primary function of the lymphatic system is absorbing and transporting macromolecules and immune cells to the general circulation, thereby regulating fluid, nutrient absorption and immune cell trafficking. Lymphangiogenesis plays an important role in tissue inflammation and tumour cell dissemination. Lymphatic involvement is seen in lymphangioleiomyomatosis (LAM) and idiopathic pulmonary fibrosis (IPF). LAM, a disease primarily affecting females, involves the lung (cystic destruction), kidney (angiomyolipoma) and axial lymphatics (adenopathy and lymphangioleiomyoma). LAM occurs sporadically or in association with tuberous sclerosis complex (TSC). Cystic lung destruction results from proliferation of LAM cells, which are abnormal smooth muscle-like cells with mutations in the TSC1 or TSC2 gene. Lymphatic abnormalities arise from infiltration of LAM cells into the lymphatic wall, leading to damage or obstruction of lymphatic vessels. Benign appearing LAM cells possess metastatic properties and are found in the blood and other body fluids. IPF is a progressive lung disease resulting from fibroblast proliferation and collagen deposition. Lymphangiogenesis is associated with pulmonary destruction and disease severity. A macrophage subset isolated from IPF bronchoalveolar lavage fluid (BALF) express lymphatic endothelial cell markers in vitro, in contrast to the same macrophage subset from normal BALF. Herein, we review lymphatic involvement in LAM and IPF.

The role of the VEGF-C/VEGFRs axis in tumor progression and therapy

Vascular endothelial growth factor C (VEGF-C) has been identified as a multifaceted factor participating in the regulation of tumor angiogenesis and lymphangiogenesis. VEGF-C is not only expressed in endothelial cells, but also in tumor cells. VEGF-C signaling is important for progression of various cancer types through both VEGF receptor-2 (VEGFR-2) and VEGF receptor-3 (VEGFR-3). Likewise, both receptors are expressed mainly on endothelial cells, but also expressed in tumor cells. The dimeric VEGF-C undergoes a series of proteolytic cleavage steps that increase the protein binding affinity to VEGFR-3; however, only complete processing, removing both the N- and C-terminal propeptides, yields mature VEGF-C that can bind to VEGFR-2. The processed VEGF-C can bind and activate VEGFR-3 homodimers and VEGFR-2/VEGFR-3 heterodimers to elicit biological responses. High levels of VEGF-C expression and VEGF-C/VEGFRs signaling correlate significantly with poorer prognosis in a variety of malignancies. Therefore, the development of new drugs that selectively target the VEGF-C/VEGFRs axis seems to be an effective means to potentiate anti-tumor therapies in the future.

Flotillin-1 promotes tumor necrosis factor-α receptor signaling and activation of NF-κB in esophageal squamous cell carcinoma cells

BACKGROUND & AIMS

The flotillin family of proteins, including flotillin-1 (FLOT1 or Reggie-2), are lipid raft proteins that initiate receptor kinase signaling and are up-regulated in several tumor types. We investigated the role of FLOT1 signaling and activation of the transcription factor nuclear factor (NF)-κB in esophageal squamous cell carcinoma (ESCC) cells.

METHODS

We used immunoblot and immunochemical analyses to determine levels of the lipid raft-associated protein FLOT1 in ESCC cell lines and 432 ESSC samples from patients; primary normal esophageal epithelial cells and matched adjacent nontumor tissues were used as controls. We determined the ability of FLOT1 to activate NF-κB using kinase, electrophoretic mobility shift, and luciferase reporter assays. We measured the effects of FLOT1 overexpression and knockdown with short hairpin RNAs in ESCC cell lines using colony formation, anchorage-independent growth, chicken chorioallantoic membrane, transwell matrix penetration, and Annexin V-binding assays. We analyzed growth of ESCC xenograft tumors in nude mice.

RESULTS

Levels of FLOT1 were increased in ESCC cell lines and samples from patients, compared with controls; protein levels correlated with disease stage and survival time. Overexpression of FLOT1 in Kyse30 and Kyse510 ESCC cell lines increased proliferation, anchorage-independent growth, and invasive activity and protected them from apoptosis. FLOT1-transduced ESCC cells formed larger tumors in nude mice than control cells (transduced with only the vector). FLOT1 facilitated recruitment of the tumor necrosis factor-α receptor to lipid rafts; promoted K63-linked polyubiquitination of the signaling intermediaries tumor necrosis factor receptor associated factor 2, receptor interacting protein, and NEMO; and sustained the activation of NF-κB. Levels of FLOT1 correlated with activation of NF-κB in ESCC samples from patients.

CONCLUSIONS

The lipid raft protein FLOT1 is up-regulated in ESCC cell lines and samples from patients and promotes ESCC cell proliferation and tumor growth in mice. FLOT1 activates tumor necrosis factor-α receptor signaling and sustains activation of NF-κB in ESCC cells.

Nuclear expression of Twist promotes lymphatic metastasis in esophageal squamous cell carcinoma

Twist-1 protein (also called Twist) has been suggested to be involved in tumor epithelial-mesenchymal transition (EMT) related progression, however, the mechanism by which twist promotes lymph node metastasis is not fully understood. In the present study, we found that nuclear twist expression is clearly correlated with lymph node (LN) metastasis as determined by immunohistochemistry (IHC). A highly invasive EC109 cell subline, EC109-P, was established by repeated in vitro transwell isolations for the cell model. Immunofluorescence (IF) assay demonstrated that nuclear twist expression was markedly higher in the highly invasive EC109-P cell line when compared with EC109 and EC9706 cells. Based on our cell model, the function and mechanism by which twist regulates LN metastasis in ESCC was investigated. The results showed that the overexpression of Twist could significantly increase the invasion and VEGF-C expression of EC9706 cells, whereas the knockdown of twist expression results in the opposite effects. This finding was further strengthened by the results of the analysis of co-expression of twist and VEGF-C by IHC in ESCC clinical samples. In summary, our study indicates that nuclear twist plays an important role in ESCC lymphatic metastasis by increasing the expression of VEGF-C. The combination of twist and VEGF-C detection could be a reliable prediction of LN metastasis in ESCC.

CCR7 and VEGF-C: molecular indicator of lymphatic metastatic recurrence in pN0 esophageal squamous cell carcinoma after Ivor-Lewis esophagectomy?

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor with a high incidence of lymph node metastasis. This study was undertaken to investigate the expression of CCR7 and VEGF-C in pN0 ESCC and its relationship with lymphatic metastatic recurrence.

METHODS

The expression of CCR7 and VEGF-C was examined by RT-PCR and immunohistochemistry. The recurrence rates were calculated by the Kaplan-Meier method and their difference was determined by log rank analysis. Cox regression analysis was performed to determine the independent risk factors.

RESULTS

In 99 patients, CCR7 mRNA expression was observed in 42 patients with a 3 year recurrence rate of 57.1%; VEGF-C mRNA expression was observed in 52 patients with a 3 year recurrence rate of 53.8%; and coexpression of CCR7 mRNA and VEGF-C mRNA was observed in 22 patients with a 3 year recurrence of 63.6%. Neither CCR7 mRNA nor VEGF-C mRNA expression was observed in 27 patients with a 3 year recurrence rate of 22.2%. The recurrence rates of patients with positive expression of CCR7 mRNA and/or VEGF-C mRNA were significantly higher than in patients without expression of both CCR7 mRNA and VEGF-C mRNA. We achieved better concordance between RT-PCR and immunohistochemistry detection of both markers. The Cox regression analysis showed tumor T classification, positive expression of CCR7/VEGF-C mRNA, and positive expression of CCR7/VEGF-C protein in tumor tissues to be independent risk factors for 3 year recurrence.

CONCLUSIONS

Patients with positive expression of CCR7 and/or VEGF-C have a higher recurrence rate than patients without expression of both CCR7 and VEGF-C. CCR7 and VEGF-C may become molecular indicators of disease in patients vulnerable to lymphatic metastatic recurrence.

Different patterns of NF-κB and Notch1 signaling contribute to tumor-induced lymphangiogenesis of esophageal squamous cell carcinoma

Background

Lymph node involvement and tumor-induced lymphangiogenesis appear as the earliest features of esophageal squamous cell carcinoma (ESCC), although the molecular regulatory mechanisms involved have remained unclear. Our aim was to investigate the contribution of NF-κB and Notch1 signaling to lymph node involvement and tumor-induced lymphangiogenesis in ESCC.

Material and methods

NF-κB and Notch1 expression in 60 tissue samples of ESCC were assessed by immunohistochemical staining. The correlations of NF-κB and Notch1 with lymph node involvement, lymphatic vessel density (LVD), podoplanin, and vascular endothelial growth factor-C (VEGF-C) were further evaluated to determine the association of NF-κB and Notch1 expression with tumor-induced lymphangiogenesis.

Results

Chi-square tests revealed that NF-κB and Notch1 expression in ESCC tissues were significant associated with lymph node metastasis, LVD, podoplanin, and VEGF-C expression. Strong expression of NF-κB, but weak expression of Notch1, was observed in tumor tissues with lymph nodes involvement (P < 0.05 for both). The mean histoscores of LVD, podoplanin, and VEGF-C staining were higher in high-NF-κB-expressing tissue than in low-expressing tissue (P < 0.05 for each). In contrast, the mean histoscores of LVD and VEGF-C staining were lower in high-Notch1-expressing tissue than in low-expressing tissue (P < 0.05 for both). A multiple factors analysis of LVD and VEGF-C further demonstrated that LVD and VEGF-C status were significantly correlated with NF-κB and Notch1 expression in tumors. NF-κB and Notch1 expression were also significantly inversely correlated (P < 0.05).

Conclusion

These results suggest that different patterns of NF-κB and Notch1 signaling contribute to lymph nodes metastasis and tumor-induced lymphangiogenesis of ESCC, and reveal that up-regulation of NF-κB is associated with down-regulation of Notch1 in tumor tissue.

Microencapsulated myoblasts transduced by the vascular endothelial growth factor (VEGF) gene for the ischemic skin flap

BACKGROUND

This experimental study aimed to explore the influence of locally administered microencapsulated vascular endothelial growth factor (VEGF)-secreting myoblasts on the survival of the ischemic skin flap in rats and to elucidate the underlying molecular mechanism.

METHODS

The pcDNA6/His A-VEGF165 plasmid was constructed, amplified, and transfected into myoblasts. Cells then were encapsulated in a sodium alginate-barium chloride microcapsule. The study investigated 64 Wistar rats (males and females). Two symmetric 2 × 10-cm, full-thickness dorsal ischemic skin flaps were elevated on each rat. One flap was used as the experiment area, and the other was used as a control. The microencapsulated VEGF-secreting myoblasts were injected into the right flap of the rat on preoperative days 0, 2, 4, and 7. The left flap in each animal was injected with the encapsulated untransfected cells. The 64 rats were randomly divided into four groups of 16 rats each.

RESULTS

The effect of the experimental group was significantly better than that of the control group. The experimental group had a certain time-dependent effect.

CONCLUSIONS

Microencapsulated VEGF-secreting-myoblasts may be a promising therapy for ischemic flaps in rats.

Detection of erbB2 copy number variations in plasma of patients with esophageal carcinoma

BACKGROUND

Mortality is high in patients with esophageal carcinoma as tumors are rarely detected before the disease has progressed to an advanced stage. Here, we sought to isolate cell-free DNA released into the plasma of patients with esophageal carcinoma, to analyze copy number variations of marker genes in the search for early detection of tumor progression.

METHODS

Plasma of 41 patients with esophageal carcinoma was prospectively collected before tumor resection and chemotherapy. Our dataset resulted heterogeneous for clinical data, resembling the characteristics of the tumor. DNA from the plasma was extracted to analyze copy number variations of the erbB2 gene using real-time PCR assays.

RESULTS

The real-time PCR assays for erbB2 gene showed significant (P = 0.001) copy number variations in the plasma of patients with esophageal carcinoma, as compared to healthy controls with high sensitivity (80%) and specificity (95%). These variations in erbB2 were negatively correlated to the progression free survival of these patients (P = 0.03), and revealed a further risk category stratification of patients with low VEGF expression levels.

CONCLUSION

The copy number variation of erbB2 gene from plasma can be used as prognostic marker for early detection of patients at risk of worse clinical outcome in esophageal cancer.

VEGF-C promotes the development of esophageal cancer via regulating CNTN-1 expression

Vascular endothelial growth factor C (VEGF-C) is a key regulator of angiogenesis and lymphangiogenesis. VEGF-C is also implicated in the development of esophageal cancer. We investigated the mRNA levels of VEGF-C and its receptors in 38 esophageal squamous cell carcinoma specimens (ESCCs) and matched adjacent normal esophageal tissues via real-time PCR. The mRNA levels of VEGF-C, VEGFR-2 and VEGFR-3 were significantly upregulated in ESCCs versus respective side normal tissues. To explore the influence of VEGF-C on esophageal cancer progression, the expression of VEGF-C was manipulated in esophageal cancer cell lines TE-1 and Eca-109. VEGF-C transcription, translation and secretion were significantly enhanced in cells stably transfected with a VEGF-C overexpression vector or attenuated in VEGF-C shRNA-transfected cell lines. In vitro, TE-1 cells stably transfected with a VEGF-C overexpression vector exhibited an increased rate of cell proliferation, migration and focus formation, whereas knockdown of VEGF-C inhibited cell proliferation, migration and focus formation. Similar results were obtained for Eca-109 cells. VEGF-C mediated biological function through transcription of CNTN-1, which is implicated in tumor invasion and metastasis. The expression of VEGF-C was correlated with that of CNTN-1 and cell proliferation and migration induced by VEGF-C were reversed by silencing of CNTN-1. In addition, nude mice inoculated with VEGF-C shRNA-transfected cells exhibited a significantly decreased tumor size in vivo via reduced VEGFR-2 and VEGFR-3 phosphorylation and microvessel formation. VEGF-C upregulation may be involved in esophageal tumor progression. Vector-based RNA interference (RNAi) targeting VEGF-C is a potential therapeutic method for human esophageal carcinoma.