Desmoglein 2 and desmocollin 2 depletions promote malignancy through distinct mechanisms in triple-negative and luminal breast cancer.

BACKGROUND: Aberrant expressions of desmoglein 2 (Dsg2) and desmocollin 2(Dsc2), the two most widely distributed desmosomal cadherins, have been found to play various roles in cancer in a context-dependent manner. Their specific roles on breast cancer (BC) and the potential mechanisms remain unclear. METHODS: The expressions of Dsg2 and Dsc2 in human BC tissues and cell lines were assessed by using bioinformatics analysis, immunohistochemistry and western blotting assays. Wound-healing and Transwell assays were performed to evaluate the cells' migration and invasion abilities. Plate colony-forming and MTT assays were used to examine the cells' capacity of proliferation. Mechanically, Dsg2 and Dsc2 knockdown-induced malignant behaviors were elucidated using western blotting assay as well as three inhibitors including MK2206 for AKT, PD98059 for ERK, and XAV-939 for ß-catenin. RESULTS: We found reduced expressions of Dsg2 and Dsc2 in human BC tissues and cell lines compared to normal counterparts. Furthermore, shRNA-mediated downregulation of Dsg2 and Dsc2 could significantly enhance cell proliferation, migration and invasion in triple-negative MDA-MB-231 and luminal MCF-7 BC cells. Mechanistically, EGFR activity was decreased but downstream AKT and ERK pathways were both activated maybe through other activated protein tyrosine kinases in shDsg2 and shDsc2 MDA-MB-231 cells since protein tyrosine kinases are key drivers of triple-negative BC survival. Additionally, AKT inhibitor treatment displayed much stronger capacity to abolish shDsg2 and shDsc2 induced progression compared to ERK inhibition, which was due to feedback activation of AKT pathway induced by ERK inhibition. In contrast, all of EGFR, AKT and ERK activities were attenuated, whereas ß-catenin was accumulated in shDsg2 and shDsc2 MCF-7 cells. These results indicate that EGFR-targeted therapy is not a good choice for BC patients with low Dsg2 or Dsc2 expression. Comparatively, AKT inhibitors may be more helpful to triple-negative BC patients with low Dsg2 or Dsc2 expression, while therapies targeting ß-catenin can be considered for luminal BC patients with low Dsg2 or Dsc2 expression. CONCLUSION: Our finding demonstrate that single knockdown of Dsg2 or Dsc2 could promote proliferation, motility and invasion in triple-negative MDA-MB-231 and luminal MCF-7 cells. Nevertheless, the underlying mechanisms were cellular context-specific and distinct.

Long non-coding RNA highly up-regulated in liver cancer promotes exosome secretion.

BACKGROUND: Highly upregulated in liver cancer (HULC) is a long non-coding RNA (lncRNA) which has recently been identified as a key regulator in hepatocellular carcinoma (HCC) progression. However, its role in the secretion of exosomes from HCC cells remains unknown. AIM: To explore the mechanism by which HULC promotes the secretion of exosomes from HCC cells. METHODS: Serum and liver tissue samples were collected from 30 patients with HCC who had not received chemotherapy, radiotherapy, or immunotherapy before surgery. HULC expression in serum exosomes and liver cancer tissues of patients was measured, and compared with the data obtained from healthy controls and tumor adjacent tissues. The effect of HULC upregulation in HCC cell lines and the relationship between HULC and other RNAs were studied using qPCR and dual-luciferase reporter assays. Nanoparticle tracking analysis was performed to detect the quantity of exosomes. RESULTS: HULC expression in serum exosomes of patients with HCC was higher than that in serum exosomes of healthy controls, and HULC levels were higher in liver cancer tissues than in tumor adjacent tissues. The expression of HULC in serum exosomes and liver cancer tissues correlated with the tumor-node-metastasis (TNM) classification, and HULC expression in tissues correlated with that in serum exosomes. Upregulation of HULC promoted HCC cell growth and invasion and repressed apoptosis. Notably, it also facilitated the secretion of exosomes from HCC cells. Moreover, qPCR assays showed that HULC repressed microRNA-372-3p (miR-372-3p) expression. We also identified Rab11a as a downstream target of miR-372-3p. Dual-luciferase reporter assays suggested that miR-372-3p could directly bind both HULC and Rab11a. CONCLUSION: Our findings illustrate the importance of the HULC/miR-372-3p/Rab11a axis in HCC and provide new insights into the molecular mechanism regulating the secretion of exosomes from HCC cells.

MicroRNA-506 is up-regulated in the development of pancreatic ductal adenocarcinoma and is associated with attenuated disease progression.

BACKGROUND: MicroRNA-506 (miR-506) has been reported to function in several tumors as a tumor suppressor gene or oncogene. However, the expression and role of miR-506 in pancreatic ductal adenocarcinoma (PDAC) remains unclear. In this study, we aimed to evaluate the phenotype of miR-506 in PDAC. METHODS: Using miRNA in situ hybridization, we examined the expression of miR-506 in 113 PDACs and 87 paired normal pancreatic tissues. We evaluated miR-506 expression in PDAC cells, normal pancreatic ducts, and acinus/islands, and we analyzed the associations between miR-506 expression and the clinicopathologic characteristics of PDAC patients. RESULTS: miR-506 expression was higher in PDAC than in matched normal pancreatic ductal cells (P < 0.001). On the other hand, the combined group of well and moderately differentiated PDACs showed higher levels of miR-506 than the poorly differentiated ones (P = 0.023). Moreover, miR-506 expression was negatively associated with pathologic T category (P = 0.004) and lymph node metastasis (P = 0.033), suggesting that miR-506 might inhibit the progression of PDAC. CONCLUSIONS: Our results suggest that miR-506 either plays a role as an oncogene in the tumorigenesis and a tumor suppressor in the progression or serves as a house-keeping, tumor-suppressing miRNA, whose expression can be activated by oncogenic signals in early development to hinder the progression of PDAC.

Changes in microRNAs associated with Twist-1 and Bcl-2 overexpression identify signaling pathways.

Epithelial-mesenchymal transition (EMT) is regulated by multiple signal transduction pathways. Twist-1 is one of the most important transcription factors in these pathways. In a previous study, we found that Bcl-2 enhanced the role of Twist-1 in EMT. Coexpression of Twist-1 and Bcl-2 may play an import role in vasculogenic mimicry (VM) through regulation of EMT. Moreover, regulators of EMT and VM are known to be important targets for microRNAs (miRNAs). To better understand how these critical pathways are induced by coexpression of Twist-1 and Bcl-2, we performed a comprehensive comparative bioinformatics analysis using microarrays on HCCs that overexpressed Twist-1 and Bcl-2. Eleven miRNAs associated with coexpression of Twist-1 and Bcl-2 were selected from the comprehensive analysis of miRNA microarray and ChIP-seq analysis. Changes in miRNAs were associated with significant differences in the expression of genes involved in signal transduction pathways related to processes including tumor invasion, metastasis, angiogenesis, and tumor cell shape. We confirmed the role of Twist-1 and Bcl-2 coexpression in HCC cells using wound healing assays, invasion assays, and 3D Matrigel assays. Furthermore, the role of miR-27a as a crucial regulator of EMT and VM was confirmed in HCC cells by RT-PCR and western blot analysis. These findings provide evidence that Bcl-2 enhances the role of Twist-1 in VM and EMT through miRNAs.

[Protective effect of arctigenin in GK rats combined with hypertension macroangiopathy].

To study the protective effect of Arctigenin in goto-kakizaki (GK) rats combined with hypertension macroangiopathy. Six-week-old GK rats were divided randomly according to blood glucose level into four groups: the model group and low, middle and high dose arctigenin groups (12.5, 25, 50 mg x kg(-1)), with Wistar rats as the normal group. All of GK rats were given high-glucose and high-fat diet. After 16 weeks, GK rats were orally administrated with 10 mg x kg(-1) x d(-1) N-Ω-nitro-L-arginine methyl ester for eight weeks. During the modeling, all of arctigenin groups were orally administrated with different dose of arctigenin twice a day; The model group and the normal group were given solvents. At the beginning, mid-term and end of the experiment, blood glucose was measured. At the end of the experiment, efforts were made to detect blood pressure, collect abdominal aortic blood after anesthesia, fix thoracic aorta after bloodletting to make paraffin sections, observe morphological characteristics and detect the expression of VEGF by immunohistochemistry. According to the results, the blood glucose rose in all GK rats, with no significant difference between the drug group and the model group. At the end of the experiment, the blood pressure significantly increased in GK rats, indicating that Arctigenin could notably reduce the blood pressure in GK rats in a dose-dependent manner. The blood routine test showed increases in both the total white blood cell count and differential blood count, MPV and PDW, abnormal blood platelet parameters and decrease in PLT in GK rats, suggesting that Arctigenin could remarkably reduce the total white blood cell count and differential blood count, MPV and PDW. The thoracic aortic morphological observation revealed obvious endangium lesions in GK rats, demonstrating that Arctigenin could ameliorate the lesion extent. VEGF immumohistochemical staining showed a higher VEGF expression in the model group but lower expression in Arctigenin groups. In conclusion, Arctigenin had a protective effect on aorta in GK rats. Its mechanism may be related to blood pressure lowering, anti-inflammation, improvement in blood platelet function and reduction of VEGF expression.

Coexpression of MYC and BCL-2 predicts prognosis in primary gastrointestinal diffuse large B-cell lymphoma.

AIM: To investigate whether MYC and BCL-2 coexpression has prognostic significance in primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) patients, and explore its associations with patients' clinical parameters. METHODS: Fresh and paraffin-embedded tumor tissue samples from 60 PGI-DLBCL patients who had undergone surgery at the Tianjin Medical University Cancer Institute and Hospital from January 2005 to May 2010 were obtained, and 30 lymphoid tissue samples from reactive lymph nodes of age- and sex-matched patients represented control samples. Staging and diagnostic procedures were conducted according to the Lugano staging system. All patients had been treated with three therapeutic modalities: surgery, chemotherapy, or radiotherapy. Expression of MYC and BCL-2 were detected at both protein and mRNA levels by immunohistochemistry and real-time RT-PCR. RESULTS: Positive expression levels of MYC and BCL-2 proteins were detected in 35% and 45% of patients, respectively. MYC+/BCL-2+ protein was present in 30% of patients. MYC and BCL-2 protein levels were correlated with high MYC and BCL-2 mRNA expression, respectively (both P<0.05). We found that advanced-stage disease (at IIE-IV) was associated with MYC and BCL-2 coexpression levels (P<0.05). In addition, MYC+/BCL-2+ patients had more difficulty in achieving complete remission than others (P<0.05). Presence of MYC protein expression only affected overall survival and progression-free survival (PFS) when BCL-2 protein was coexpressed. The adverse prognostic impact of MYC+/BCL-2+ protein on PFS remained significant (P<0.05) even after adjusting for age, Lugano stage, international prognostic index, and BCL-2 protein expression in a multivariable model. CONCLUSION: MYC+/BCL-2+ patients have worse chemotherapy response and poorer prognosis than patients who only express one of the two proteins, suggesting that assessment of MYC and BCL-2 expression by immunohistochemistry has clinical significance in predicting clinical outcomes of PGI-DLBCL patients.

Key nodes of a microRNA network associated with the integrated mesenchymal subtype of high-grade serous ovarian cancer.

Metastasis is the main cause of cancer mortality. One of the initiating events of cancer metastasis of epithelial tumors is epithelial-to-mesenchymal transition (EMT), during which cells dedifferentiate from a relatively rigid cell structure/morphology to a flexible and changeable structure/morphology often associated with mesenchymal cells. The presence of EMT in human epithelial tumors is reflected by the increased expression of genes and levels of proteins that are preferentially present in mesenchymal cells. The combined presence of these genes forms the basis of mesenchymal gene signatures, which are the foundation for classifying a mesenchymal subtype of tumors. Indeed, tumor classification schemes that use clustering analysis of large genomic characterizations, like The Cancer Genome Atlas (TCGA), have defined mesenchymal subtype in a number of cancer types, such as high-grade serous ovarian cancer and glioblastoma. However, recent analyses have shown that gene expression-based classifications of mesenchymal subtypes often do not associate with poor survival. This "paradox" can be ameliorated using integrated analysis that combines multiple data types. We recently found that integrating mRNA and microRNA (miRNA) data revealed an integrated mesenchymal subtype that is consistently associated with poor survival in multiple cohorts of patients with serous ovarian cancer. This network consists of 8 major miRNAs and 214 mRNAs. Among the 8 miRNAs, 4 are known to be regulators of EMT. This review provides a summary of these 8 miRNAs, which were associated with the integrated mesenchymal subtype of serous ovarian cancer.

Role of Bcl-2 and its associated miRNAs in vasculogenic mimicry of hepatocellular carcinoma.

OBJECTIVE: An investigation of the role of the anti-apoptotic protein Bcl-2 and its associated miRNAs in vasculogenic mimicry (VM) in hepatocellular carcinoma. METHODS: The Bcl-2 expression plasmid was constructed for transfection into the hepatocellular carcinoma cell line HepG2. Changes in the expression profiles of the miRNAs induced by Bcl-2 overexpression and their relationships with vasculogenic mimicry were analysed. Real-time PCR was performed in frozen tissue specimens from 42 cases of hepatocellular carcinoma to analyse the relationship between Bcl-2 and miR-27a; Immunohistochemical staining was performed in paraffin-embedded tissue samples from 97 cases of hepatocellular carcinoma to analyse the relationship between Bcl-2 expression and the expression of vasculogenic mimicry (VM) related molecules VEGF and HIF1A, which were target genes of the Bcl-2 related miRNAs. RESULTS: Overexpression of Bcl-2 results in a significant change in the expression of a wide range of miRNAs, and the target genes of these miRNAs are composed of various vasculogenic mimicry related genes; Bcl-2 expression was positively correlated with the expression of the miRNA target genes VEGF and HIF1A. The expression of VEGF and HIF1A was significantly and positively correlated with VM and poor prognosis of patients. CONCLUSION: Bcl-2 may play a role in vasculogenic mimicry through miRNAs by targeting angiogenesis associated genes.

Study on the relationship between CXCR4 expression and perineural invasion in pancreatic cancer.

BACKGROUND: Recent reports have shown that C-X-C chemokine receptor 4 (CXCR4) plays an important role in metastasis. Despite a clear understanding of the protein's structure and properties, its functional role remains elusive. We conducted the present study to evaluate the expressions of CXCR4 in pancreatic cancer, and to investigate its relationship with clinicopathological parameters, especially perineural invasion(PNI). MATERIALS AND METHODS: The association between CXCR4 expression and perineural invasion was determined by immunohistochemistry in pancreatic cancer patients (n=51). RESULTS: CXCR4 expression was correlated with the existence of PNI and the type of PNI (p=0.042, p=0.040). TIMP-2 expression was also correlated with the existence, the pathway and degree of PNI (p=0.000, p=0.006, p=0.000). CONCLUSIONS: Our results suggest an association between PNI and expression of CXCR4 and TIMP-2 in pancreatic cancer. CXCR4 may promote the occurrence of PNI in pancreatic cancer cells by decreasing the inhibition of TIMPs on MMP.

Resistance to apoptosis should not be taken as a hallmark of cancer.

In the research community, resistance to apoptosis is often considered a hallmark of cancer. However, pathologists who diagnose cancer via microscope often see the opposite. Indeed, increased apoptosis and mitosis are usually observed simultaneously in cancerous lesions. Studies have shown that increased apoptosis is associated with cancer aggressiveness and poor clinical outcome. Furthermore, overexpression of Bcl-2, an antiapoptotic protein, is linked with better survival of cancer patients. Conversely, Bax, CD95, Caspase-3, and other apoptosis-inducing proteins have been found to promote carcinogenesis. This notion of the role of apoptosis in cancer is not new; cancer cells were found to be short-lived 88 years ago. Given these observations, resistance to apoptosis should not be considered a hallmark of cancer.

Prognostic factors associated with solitary plasmacytoma.

Solitary plasmacytoma (SP) is a rare tumor with low incidence. The aim of this study was to investigate the clinical features, treatment strategies, and relative prognostic factors of 66 patients with SP. These patients made up 10.25% of the 644 patients with plasma cell dyscrasias treated at the Tianjin Medical University Cancer Institute and Hospital over the past 12 years. SP always presented with either solitary bone plasmacytoma (SBP) or extramedullary plasmacytoma (EMP), as determined by the location of the lesions. SBP occurred most frequently in the vertebral column and EMP in the upper respiratory tract. In addition to other factors, tumor size, serum M protein level, urinary Bence Jones protein level, and disease progression toward multiple myeloma were significantly different between the two groups (P<0.05). Larger tumor size (≥5 cm) was associated with poor prognosis of local control, multiple myeloma-free survival, overall survival and progression-free survival for SBP patients. Radiotherapy and serum ß2 microglobulin <3.5 mg/L were favorable prognostic factors for local control, multiple myeloma-free survival, and progression-free survival in patients with EMP.

[Clinical features and outcome analyses of newly-diagnosed multiple myeloma with extramedullary involvements].

OBJECTIVE: To explore the clinical features and prognostic factors of newly-diagnosed multiple myeloma (MM) with extramedullary (EM) involvements. METHODS: The clinical features, efficacies, survival rates and prognostic factors were retrospectively analyzed in 46 MM patients with EM (group A) from January 2000 to October 2011. And another 53 MM patients without EM (group B) were selected as the controls. RESULTS: The median age of Group A was 58 years. Compared with group B, the incidence of EM was associated with a higher level of ß2-microglobulin (ß2-MG) and extensive bone disease. The most common location of EM was soft tissues. And the total effective rates of groups A and B were 58.5% (24/41) and 78.8% (41/52) respectively. The difference was statistically significant (P = 0.042). The median follow-up time was 28(2-88) months. The estimated overall survival (OS) of the patients with EM was significantly shorter than those without EM (42.6 vs 53.9 months, P = 0.009). Log-rank univariate analysis showed that the number of osteolytic lesions ≥ 3, ß2-MG ≥ 5.5 mg/L, hemoglobin ≤ 110 g/L and albumin ≤ 30 g/L were poor prognostic factors in MM patients with EM. Multivariate analysis with Cox model showed only the number of osteolytic lesions ≥ 3 (OR = 2.327, 95%CI: 1.282 - 4.224) and ß2-MG ≥ 5.5 mg/L (OR = 2.677, 95%CI: 1.092 - 6.566) were statistically significant. CONCLUSIONS: Multiple EM lesions may be involved in MM patients. For the patients with EM, the response to conventional chemotherapy is poor and the prognosis is unfavorable, especially for those with a high level of ß2-MG or the number of osteolytic lesions ≥ 3.

Vasculogenic mimicry is a key prognostic factor for laryngeal squamous cell carcinoma: a new pattern of blood supply.

BACKGROUND: Recurrence and local lymph node metastasis affected the prognosis of patients with laryngeal cancer. The aim of this study was to analyze clinical and pathological significance of vasculogenic mimicry (VM) in laryngeal squamous cell carcinoma (LSCC) and evaluate its contribution to prognosis. METHODS: Data of 168 cases of LSCC were reviewed retrospectively to reveal clinical pathology and prognostic significance of VM. CD31 and periodic acid-Schiff double staining was used to identify VM. RESULTS: VM in LSCC contributed to lymph node metastasis (P = 0.003) and clinical progression. VM correlated to histopathology grade (P = 0.001) of LSCC. VM was an adverse prognostic factor for both disease-specific survival (P = 0.039) and metastasis-free survival (P = 0.042) by univariate survival analyses. And it was an independent prognostic factor for only disease-specific survival (P = 0.003) by multivariate survival analyses. CONCLUSIONS: VM existed in LSCC. LSCC with VM has more potential to invasion and metastasis.

[Role of vasculogenic mimicry and endothelium-dependent vessel in metastasis of laryngeal cancer].

OBJECTIVE: To investigate the contribution of vasculogenic mimicry (VM) and endothelium-dependent vessel (EDV) to invasion and metastasis of laryngeal squamous cell carcinoma (LSCC). METHODS: A total of 203 cases with LSCC was reviewed and followed up. VM and EDV in LSCC tissues were assessed by double staining with anti-CD31 immunohistochemistry and periodic acid-schiff. Kruskal-Wallis test and one-way ANOVA were used to analyze the relationship between VM, EDV and clinical pathology parameters of LSCC. Kaplan-Meier analysis was used to evaluate overall survival (OS) of patients with LSCC. RESULTS: VM related to pTNM stage, lymph node metastasis and pathology grade of LSCC, while EDV related to primary sites, pTNM stage, T stage and distant metastasis of LSCC. Univariate analysis showed VM (P = 0.014), pTNM stage (P = 0.009), T stage (P = 0.013), nodal status (P = 0.013), histopathology grade (P = 0.038), tumor size (P = 0.028), and radiotherapy (P < 0.0001) related to OS. VM (P = 0.011), primary sites (P = 0.049), tumor size (P = 0.001) and radiotherapy (P < 0.0001) related to disease free survival. Multivariate analysis indicated that VM was an adverse predictor for both OS and disease free survival. CONCLUSIONS: Both VM and EDV existed in LSCC. VM contributed to progression of LSCC through promoting lymph node metastasis. VM is an independent predictor for the prognosis of LSCC.

Hypoxia-induced vasculogenic mimicry formation via VE-cadherin regulation by Bcl-2.

Vasculogenic mimicry (VM) refers to the unique ability of highly aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks. Hypoxia plays a pivotal role in the formation of VM. Hypoxia-induced Bcl-2 overexpression is observed in many types of tumors including melanoma, in which it is associated with tumorigenicity and angiogenesis. VE-cadherin, the major endothelial adhesion molecule controlling cellular junctions and blood vessel formation, is also overexpressed in melanoma. Despite these connections, whether hypoxia induces VM formation via VE-cadherin regulation by Bcl-2 is not confirmed. We used human melanoma cells to upregulate or knockdown the expression of Bcl-2 to investigate the possible molecular mechanism of VM formation under hypoxia. Bcl-2 overexpression increased VE-cadherin expression and VM formation under normoxia, whereas Bcl-2 siRNA significantly decreased VE-cadherin expression and VM formation under hypoxia. We then demonstrated that Bcl-2 regulated VE-cadherin transcription activity by Western blot, three-dimensional cultures, reporter gene assay, and clinical analysis. Therefore, Bcl-2-dependent VE-cadherin overexpression may be an important mechanism by which hypoxia induces VM.

Coexpression of Bcl-2 with epithelial-mesenchymal transition regulators is a prognostic indicator in hepatocellular carcinoma.

The anti-apoptosis factor Bcl-2 is known to contribute to tumorigenesis and metastasis. Epithelial-mesenchymal transition (EMT) may also participate in tumor invasion and metastasis. This study investigated the relationship between coexpression profiles of Bcl-2 and EMT regulators in hepatocellular carcinoma (HCC) tumor samples and clinical outcome. The nuclear (Nu) and cytoplasmic (Cyt) expression of Bcl-2 and the EMT regulators Twist-1, Twist-2, and Snail were determined by immunohistochemical staining in tumor tissue isolated from 97 HCC patients. The clinical prognostic values of both individual protein expression and various expression combinations were investigated using univariate and multivariate survival analysis. Results showed that patients with nuclear expression of Bcl-2 had worse clinical outcomes than patients exhibiting cytoplasmic expression. Overall survival was significantly shorter in HCC patients individually expressing Bcl-2-Nu, Twist-1-Nu, Twist-1-Cyt, and Snail (all P<0.05). Patients coexpressing Bcl-2-Nu with Twist-1-Nu, Twist-1-Cyt, Twist-2, or Snail had even worse prognoses than those expressing no biomarker or any one biomarker alone (all P<0.05). Multivariate analysis showed that HCC patients coexpressing Bcl-2-Nu with Twist-1-Cyt had the worst prognosis. This study provides clinical evidence that nuclear expression of Bcl-2 combined with cytoplasmic expression of Twist-1 is a predictor of very poor prognosis in HCC. Coexpression profiles of Bcl-2 and EMT regulators might aid in the selection of the most efficacious therapy for patients with HCC.

Predictive value of circulating endothelial cells for efficacy of chemotherapy with Rh-endostatin in non-small cell lung cancer.

PURPOSE: The present study was designed to elucidate the fluctuation of activated CECs (aCECs) during different therapies and to investigate their predictive value for efficacy of anti-angiogenesis and chemotherapy in advanced non-small cell lung cancer (NSCLC). METHODS: Seventy-two patients were randomized into three arms, treated with concomitant NP (vinorelbine and cisplatin) and Rh-endostatin, Rh-endostatin followed by NP, and single NP up to a maximum of six cycles. Response, time to progression (TTP), and aCECs levels were observed. The correlation between aCECs and efficacy was analyzed. RESULTS: We found that TTP was 8.5 months in concomitant NP and Rh-endostatin versus 5.3 months in NP (p = 0.04) and 6.0 months in Rh-endostatin followed by NP. aCECs fluctuated during the therapeutic period, with a significantly high level from baseline on 8th day of Rh-endostatin followed by NP regimen, that is, when single Rh-endostatin was administered for 1 week, and upon completion of therapy in cases of progressive disease in each group (all p < 0.05). When TTP was longer than 10 months, aCECs count difference (∆aCECs, the difference in the aCECs by post-therapeutic amount minus pre-therapeutic amount) was reversely correlated to TTP (p = 0.003, r = -0.647). CONCLUSIONS: An improved synergistic effect was achieved from concomitant NP and Rh-endostatin compared with Rh-endostatin followed by NP and single NP. aCECs increased when the disease was aggravated or single Rh-endostatin treatment of Rh-endostatin was administered, while they decreased when a clinical response to the combined therapy was obtained. Our results suggest ∆aCECs as an ideal marker to predict the response to Rh-endostatin combined with chemotherapy.

[Overexpression of the receptor tyrosine kinase EphA2 in choroidal melanoma: correlation with vesculogenic mimicry and prognosis].

OBJECTIVE: To study the correlation of EphA2 protein expression with vesculogenic mimicry (VM), clinicopathological characteristics and prognosis in choroidal melanoma (CM). METHODS: It was a retrospective case series study. Between January 1992 and December 2005, 56 cases of human CM with clinicopathologic data from the Second Hospital of Tianjin Medical University were studied. HE stainings were performed to observe the microcirculation patterns in tumor tissue specimens. VM was found in 26 of the 56 cases using CD31/periodic acid-Schiff (PAS) double staining and transelectron microscopy. All cases were divided into two groups: VM-positive and VM-negative. Immunohistochemical staining was performed on paraffin sections of the 56 cases of CM specimens to investigate the expression of EphA2. According to tumor cells positive rate and staining intensity of the results of evaluation, the specimens were divided into low expression and high expression groups.χ(2)-test and t-test were used to analyzed the enumeration data and measurement data, respectively. Survival analysis was used to further elucidate its correlation with clinicopathological characteristics, VM and prognosis. Cox proportional hazard model was used to analyzed the influence factors of prognosis. RESULTS: VM channels were found in 26 of the 56 CM cases and VM-negative 30 cases. VM-positivity was related to cell type, tumor size and recurrence and metastasis, and the differences were statistically significant (χ(2) = 4.612, 5.346, 5.213; P = 0.036, 0.021, 0.027). The results showed that EphA2 was up-regulated in the VM-positive group compared with the group of VM-negative group. The positive rates of EphA2 expression in the VM-positive group and VM-negative group were 92.3% (25/26) and 70.0% (21/30), respectively, with a significant difference between the two groups (t = 2.247, P = 0.009). The EphA2 protein was expressed in epithelioid (10/12), mixed (11/15) and spindle (41.40%) cell types, with a significant difference among these histological types (χ(2) = 6.513, P = 0.010). The expression rate of EphA2 protein were significantly higher in large (54.55%, 18/33) than small (45.45%, 15/33) tumors, and the expression of EphA2 in metastatic and recurrence patients (10/11) were significantly higher compared with controls (31.11%, 14/45) (χ(2) = 4.556, 8.211;P = 0.016, 0.005). Kaplan-Meier survival analysis showed the presence of VM resulted in a poor prognosis (t = 9.263, P = 0.000). The Cox proportional hazards model indicated that the EphA2 overexpression and the presence of VM were independent predictors of a poor prognosis (χ(2) = 12.041, P = 0.001). Moreover, there was a significant positive correlation between them (r = 0.412, P < 0.05). CONCLUSION: The results of this study demonstrate that EphA2 may play a critical role in the formation process of VM in CM, implicating EphA2 as a valuable marker for the prediction of recurrence, metastasis and prognosis in CM patients.

Promoting melanoma growth and metastasis by enhancing VEGF expression.

Angiogenesis plays an essential role in tumor growth and metastasis and is a promising target for cancer therapy. Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis. The present study was designed to determine the role of VEGF in tumor growth and metastasis. The sequences for the VEGF gene were cloned into expression plasmids and then transfected into melanoma B16 cells. Overexpression of VEGF transfected with expression plasmids or given exogenous VEGF and epidermal growth factor (EGF) significantly enhanced tumor cell proliferation, migration, and invasion. Tumor growth and metastasis of melanoma B16 cells transfected with VEGF plasmid were significantly promoted compared with those of cells administered with exogenous VEGF or EGF. These results indicated that VEGF can be an effective antiangiogenic strategy for melanoma.

Autophagy enhances the aggressiveness of human colorectal cancer cells and their ability to adapt to apoptotic stimulus.

OBJECTIVE: To investigate LC3B-II and active caspase-3 expression in human colorectal cancer to elucidate the role of autophagy, and to explore the relationship of autophagy with apoptosis in human colorectal cancer. METHODS: LC3B expression was detected by immunohistochemistry in 53 human colorectal cancer tissues and 20 normal colon tissues. The protein levels of LC3B-II and active caspase-3 were also determined by Western blot analysis in 23 human colorectal cancer tissues and 10 normal colon tissues. RESULTS: LC3B was expressed both in cancer cells and normal epithelial cells. LC3B expression in the peripheral area of cancer tissues was correlated with several clinicopathological factors, including tumor differentiation (P=0.002), growth pattern of the tumor margin (P=0.028), pN (P=0.002), pStage (P=0.032), as well as vessel and nerve plexus invasion (P=0.002). The protein level of LC3B-II in cancer tissue was significantly higher than in normal tissue (P=0.038), but the expression of active forms of procaspase-3 in cancer tissue was lower (P=0.041). There was a statistically significant positive correlation between the expression levels of LC3B-II and the active forms of procaspase-3 (r=0.537, P=0.008). CONCLUSIONS: Autophagy has a prosurvival role in human colorectal cancer. Autophagy enhances the aggressiveness of colorectal cancer cells and their ability to adapt to apoptotic stimulus.