A 3D fibrous scaffold inducing tumoroids: a platform for anticancer drug development

The development of a suitable three dimensional (3D) culture system for anticancer drug development remains an unmet need. Despite progress, a simple, rapid, scalable and inexpensive 3D-tumor model that recapitulates in vivo tumorigenesis is lacking. Herein, we report on the development and characterization of a 3D nanofibrous scaffold produced by electrospinning a mixture of poly(lactic-co-glycolic acid) (PLGA) and a block copolymer of polylactic acid (PLA) and mono-methoxypolyethylene glycol (mPEG) designated as 3P. Cancer cells cultured on the 3P scaffold formed tight irregular aggregates similar to in vivo tumors, referred to as tumoroids that depended on the topography and net charge of the scaffold. 3P scaffolds induced tumor cells to undergo the epithelial-to-mesenchymal transition (EMT) as demonstrated by up-regulation of vimentin and loss of E-cadherin expression. 3P tumoroids showed higher resistance to anticancer drugs than the same tumor cells grown as monolayers. Inhibition of ERK and PI3K signal pathways prevented EMT and reduced tumoroid formation, diameter and number. Fine needle aspirates, collected from tumor cells implanted in mice when cultured on 3P scaffolds formed tumoroids, but showed decreased sensitivity to anticancer drugs, compared to tumoroids formed by direct seeding. These results show that 3P scaffolds provide an excellent platform for producing tumoroids from tumor cell lines and from biopsies and that the platform can be used to culture patient biopsies, test for anticancer compounds and tailor a personalized cancer treatment.

Fibronectin overexpression is associated with latent membrane protein 1 expression and has independent prognostic value for nasopharyngeal carcinoma

Despite recent improvements in the diagnosis and treatment, the final outcomes in patients with nasopharyngeal carcinomas (NPC) still remain suboptimal. Through data mining from published transcriptomic database with further bioinformatic validation, fibronectin (FN1) was identified as a differentially upregulated gene in NPC tissues, which implicates the transition from epithelial to mesenchymal phenotype (EMT) and promotes metastasis. Given the roles of fibronectin in risk stratification and in the frontline therapeutics of common carcinomas, such as renal cell cancer, we explored fibronectin immunoexpression status and its associations with clinicopathological variables and survival in a well-defined cohort of NPC patients. Fibronectin immunohistochemistry was retrospectively performed and analyzed using H-score for 124 biopsy specimens from NPC patients who received standard treatment without distant metastasis at initial diagnosis. Those cases with H-score higher than the median value were regarded as fibronectin overexpression. The findings were correlated with clinicopathological variables, EBV latent membrane protein 1 (LMP1) expression, disease-specific survival (DSS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS). Fibronectin overexpression was significantly associated with American Joint Committee on Cancer (AJCC) stages III-IV (p = 0.019) and LMP1 expression (p = 0.004), and univariately predictive of adverse outcomes for DSS, DMFS, and LRFS (all p < 0.0001). In the multivariate comparison, fibronectin overexpression still remained prognostically independent to portend worse DSS (p < 0.01, hazard ratio = 5.958), DMFS (p < 0.01, hazard ratio = 5.728), and LRFS (p < 0.01, hazard ratio = 5.411) together with a vanced AJCC stages III-IV. Fibronectin is upregulated in a subset of NPCs, and its increased immunoexpression significantly correlated with advanced features, justifying the potentiality of fibronectin as a theragnostic biomaker of NPC.

Epithelial-mesenchymal transition phenotypes are associated with patient survival in intrahepatic cholangiocarcinoma

BACKGROUND

The aim of this study was to evaluate the epithelial-mesenchymal transition (EMT) and to assess its prognostic significance in intrahepatic cholangiocarcinoma.

METHODS

We performed immunohistochemical stainings for E-cadherin, β-catenin, vimentin and fibronectin in a total of 85 cases.

RESULTS

Expression of vimentin and reduced expression of E-cadherin were found to show correlation with poor differentiation (p=0.017, p=0.010). Reduced expression of β-catenin showed significant association with poor differentiation (p=0.023), tumour size (p=0.028) and lymph node metastasis (p=0.011). According to the expression pattern of E-cadherin, β-catenin, vimentin and fibronectin we categorised four phenotypes: complete type, hybrid type, null type and wild type. The complete type of β-catenin with vimentin or fibronectin was found to show an association with lymph node metastasis (p=0.048, p=0.012). Significantly worse overall survival (OS) and disease-free survival (DFS) was observed for the complete type, and the best OS and DFS were observed for the wild type.

CONCLUSIONS

EMT phenotypes can be useful markers for prediction of patient outcomes.

Over-expression of the special AT rich sequence binding protein 1 (SATB1) promotes the progression of nasopharyngeal carcinoma: association with EBV LMP-1 expression

BACKGROUND

Special AT rich sequence binding protein 1 (SATB1) plays a crucial role in the biology of various types of human cancer. However, the role of SATB1 in human nasopharyngeal carcinoma (NPC) remains unknown. In the present study, we sought to investigate the contribution of aberrant SATB1 expression in the progression of NPC and its association with the Epstein Barr virus (EBV)-encoded latent membrane protein 1 (LMP-1).

METHODS

Immunohistochemical analysis was performed to detect SATB1 and LMP-1 protein in clinical samples, and the association of SATB1 protein expression with patient clinicopathological characteristics and LMP-1 expression were analyzed. SATB1 expression profiles were evaluated in well-differentiated NPC cell line CNE1, poorly-differentiated CNE2Z, undifferentiated C666-1 and immortalized nasopharyngeal epithelia NP-69 cells using quantitative RT-PCR, western blotting and fluorescent staining. After inhibition the SATB1 expression by using SATB1 specific small interfering RNA in these cell lines, the change of cell proliferation was investigated by western blotting analysis of PCNA (proliferating cell nuclear antigen) expression and CCK-8 assay, and the cell migration was assessed by Transwell migration assay. Finally, the expressions of SATB1 and PCNA were examined in CNE1 cells that forced LMP-1 expression by fluorescent staining and RT-PCR.

RESULTS

Immunohistochemical analysis revealed that SATB1 protein expression was elevated in NPC tissues compared to benign nasopharyngeal tissues (P = 0.005). Moreover, high levels of SATB1 protein expression were positively correlated with clinical stage (P = 0.025), the status of lymph node metastasis (N classification) (P = 0.018), distant metastasis (M classification) (P = 0.041) and LMP-1 expression status (r = 2.35, P < 0.01) in NPC patients. In vitro experiments demonstrated that an inverse relationship between SATB1 expression and NPC differentiation status, with SATB1 weakly expressed in NP-69 cells and CNE1 cells, and significant increasingly expressed in CNE-2Z and C666-1 cells. Targeted knockdown of SATB1 expression obviously attenuated the proliferation and migration of highly SATB1-expressing CNE2Z and C666-1 cells, but not NP-69 and CNE1 cells. Interestingly, forced LMP-1 expression in CNE1 cells led to a surprisingly increasing SATB1 expression and nuclear location, companying with an up-regulated PCNA expression.

CONCLUSIONS

Our results reveal that EBV LMP-1-mediated over-expression of SATB1 is associated with NPC progression, suggesting SATB1 may represent a promising biomarker and therapeutic target for NPC.

Current and future biologic markers for disease progression and relapse in testicular germ cell tumors: a review

Testicular germ cell tumors represent a biologically unique disease process. These tumors are exquisitely sensitive to platinum-based chemotherapy, can be cured with surgical metastasectomy, and are known for the integration of biologic markers to stage and assign risk. Exploring further biologic markers that offer insight into the molecular mechanisms that contribute to disease biology is important. In this review, we attempt to summarize the utility of the current and some future biologic markers for disease monitoring and relapse.

Epigenetic regulation of miRNA-211 by MMP-9 governs glioma cell apoptosis, chemosensitivity and radiosensitivity

Glioblastoma multiforme (GBM) is the most aggressive brain cancer, and to date, no curative treatment has been developed. In this study, we report that miR-211, a microRNA predicted to target MMP-9, is suppressed in grade IV GBM specimens. Furthermore, we found that miR-211 suppression in GBM involves aberrant methylation-mediated epigenetic silencing of the miR-211 promoter. Indeed, we observed a highly significant inverse correlation between miR-211 expression and MMP-9 protein levels, which is indicative of post-transcriptional control of gene expression. Additionally, shRNA specific for MMP-9 (pM) promoted miR-211 expression via demethylation of miR-211 promoter-associated CpG islands (-140 to +56). In independent experiments, we confirmed that miR-211 overexpression and pM treatments led to the activation of the intrinsic mitochondrial/Caspase-9/3-mediated apoptotic pathway in both glioma cells and cancer stem cells (CSC). We also investigated whether miR-211 is involved in the regulation of MMP-9 and thus plays a functional role in GBM. We found an acute inhibitory effect of miR-211 on glioma cell invasion and migration via suppression of MMP-9. Given the insensitivity of some GBMs to radiation and chemotherapy (temozolomide) along with the hypothesis that glioma CSC cause resistance to therapy, our study indicates that miR-211 or pM in combination with ionizing radiation (IR) and temozolomide significantly induces apoptosis and DNA fragmentation. Of note, miR-211- and pM-treated CSC demonstrated increased drug retention capacity, as observed by MDR1/P-gp mediated-Rhodamine 123 drug efflux activity assay. These results suggest that either rescuing miR-211 expression or downregulation of MMP-9 may have a new therapeutic application for GBM patients in the future.

Functional polymorphisms of matrix metalloproteinase-9 and survival in patients with locoregionally advanced nasopharyngeal carcinoma treated with chemoradiotherapy

To investigate the prognostic role of major matrix metalloproteinase (MMP) gene polymorphisms in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) treated with chemoradiotherapy. Four hundred twenty-one consecutive NPC patients were prospectively recruited. Two hundred patients were randomly selected as the training cohort, and the remaining 221 patients were the validation cohort. Twelve polymorphisms in the MMP-1, 2, 3, 7, 8, and 9 genes were genotyped by ligase detection reaction-PCR. MMP-9 rs2250889 PR/RR (HR = 2.287, 95% CI 1.400-3.735) and rs17576 RQ/QQ (HR = 2.347, 95% CI 1.431-3.849) genotypes were significantly related with increased death risk in the training cohort. Analysis of the validation cohort confirmed these results (rs2250889: HR = 2.231, 95% CI 1.281-3.886; rs17576: HR = 2.987, 95% CI 1.674-5.330). Multivariate analysis showed that rs17576 (HR = 2.284, 95% CI 1.123-4.643, P = 0.023) was still an independent prognostic factor. The MMP-9 rs17576 is a novel independent prognostic marker in patients with locoregionally advanced NPC treated with chemoradiotherapy.

MicroRNAs in domestic livestock

microRNAs (miRNAs) are a class of small noncoding RNA that bind to complementary sequences in the untranslated regions of multiple target mRNAs resulting in posttranscriptional regulation of gene expression. The recent discovery and expression-profiling studies of miRNAs in domestic livestock have revealed both their tissue-specific and temporal expression pattern. In addition, breed-dependent expression patterns as well as single nucleotide polymorphisms in either the miRNA or in the target mRNA binding site have revealed associations with traits of economic importance and highlight the potential use of miRNAs in future genomic selection programs.

Growth and differentiation factor 3 induces expression of genes related to differentiation in a model of cancer stem cells and protects them from retinoic acid-induced apoptosis

Misexpression of growth factors, particularly those related to stem cell-like phenotype, is often observed in several cancer types. It has been found to influence parameters of disease progression like cell proliferation, differentiation, maintenance of undifferentiated phenotype and modulation of the immune system. GDF3 is a TGFB family member associated with pluripotency and differentiation during embryonic development that has been previously reported to be re-expressed in a number of cancer types. However, its role in tumor development and progression has not been clarified yet. In this study we decipher the role of GDF3 in an in vitro model of cancer stem cells, NCCIT cells. By classical approach to study protein function combined with high-throughput technique for transcriptome analysis and differentiation assays we evaluated GDF3 as a potential therapeutic target. We observed that GDF3 robustly induces a panel of genes related to differentiation, including several potent tumor suppressors, without impacting the proliferative capacity. Moreover, we report for the first time the protective effect of GDF3 against retinoic acid-induced apoptosis in cells with stem cell-like properties. Our study implies that blocking of GDF3 combined with retinoic acid-treatment of solid cancers is a compelling direction for further investigations, which can lead to re-design of cancer differentiation therapies.

Aberrant expression of S100A6 and matrix metalloproteinase 9, but not S100A2, S100A4, and S100A7, is associated with epidermal carcinogenesis

BACKGROUND

S100 proteins belong to a family of calcium-binding proteins that regulate cell proliferation and differentiation. Despite our growing knowledge about the biology of S100 proteins in some human cancers, little is known about the expression of S100 family members in epidermal tumors and their clinical significance.

OBJECTIVE

To determine the expression of S100A2, S100A4, S100A6, S100A7, as well as matrix metalloproteinases 9 (MMP9) in a spectrum of epidermal tumors with benign and malignant characteristics.

METHODS

Immunohistological staining was performed for S100A2, S100A4, S100A6, S100A7, and MMP9 in 101 cases of various types of epidermal tumors, viz., squamous cell carcinoma (SCC), Bowen's disease (BD), actinic keratosis (AK), basal cell carcinoma (BCC), keratoacanthoma (KA), and seborrheic keratosis (SK). Thirteen specimens of normal skin (NS) served as control.

RESULTS

S100A2, S100A6, and S100A7 positive immunostaining was variably observed in different epidermal tumors. S100A4 staining was not observed in any epidermal tumors, but was clearly visible in dendritic cells. MMP9 immunostaining was positive only in 22/26 (84.62%) of SCC and 2/15 (13.33%) of BD cases. Expression of S100A2, S100A6, and S100A7 was increased in tumor cells compared to NS. However, only S100A6 expression was significantly associated with malignant transformation of epidermal tumors. Moreover, S100A6 expression was correlated with MMP9 expression in metastatic SCC.

CONCLUSIONS

Epidermal tumors show increased expression of S100A2 and S100A7 proteins. S100A4 may be a useful and distinct marker for epidermal dendritic cells. Expression of S100A6 and MMP9 in combination is associated with the development of SCC.

ID1 regulates U87 human cell proliferation and invasion

Despite therapeutic advances, the prognosis of patients diagnosed with malignant glioma has not improved in recent years. In particular, the molecular mechanisms that mediate glioma invasion remain poorly understood. The importance of ID1 in promoting tumor invasion and metastasis has recently emerged and a role for ID1 as a possible molecular marker of tumor aggressiveness has been proposed. To investigate the biological function of ID1 in glioblastomas, ID1-silenced U87 glioblastoma multiforme (GBM) cells were constructed using a small hairpin RNA (shRNA) sequence. The effect of the knockdown of ID1 on proliferation and invasion in these cells was analyzed using the 5-bromo-2′-deoxy-uridine cell proliferation, Transwell invasion, scratch and cell adhesion assays. Compared with the controls, the U87 cells expressing ID1-shRNA exhibited a significantly decreased proliferation and invasion capacity (P<0.05), as well as increased cell adhesion. Furthermore, silencing ID1 reduced the expression of c-Myc, cyclin D1 and β-catenin, while increasing E-cadherin expression in U87 cells. This study showed that ID1 regulates the metastatic potential of GBM cells by controlling the epithelial-mesenchymal transition. Therefore, ID1 is a potential prognostic indicator and therapeutic target in glioblastomas.

Intelligently targeted drug delivery and enhanced antitumor effect by gelatinase-responsive nanoparticles

AIMS

The matrix metalloproteinase (MMP) 2/9, also known as collagenases IV and gelatinases A/B, play a key role in cancer invasion and metastasis. However, the clinical trials of the MMP inhibitors (MMPIs) ended up with disappointing results. In this paper, we synthesized a gelatinase-responsive copolymer (mPEG-PCL) by inserting a gelatinase cleavable peptide (PVGLIG) between mPEG and PCL blocks of mPEG-PCL for anticancer drug delivery to make use of MMP2/9 as an intelligent target for drug delivery.

MATERIALS AND METHODS

mPEG-pep-PCL copolymer was synthesized via ring-opening copolymerization and double-amidation. To evaluate whether Nanoparticles (NPs) prepared from this copolymer are superior to NPs prepared from mPEG-PCL, NPs prepared from mPEG-PCL copolymer were used as positive control. Docetaxel-loading NPs using mPEG-pep-PCL and mPEG-PCL were prepared by nano-precipitation method, mentioned as Gel-NPs and Con-NPs, respectively. The morphologic changes of the NPs after treatment with gelatinases were observed macroscopically by spectrophotometer and microscopically by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The cellular uptake amount and cytotoxicity of Gel-NPs and Con-NPs, respectively, in cell lines with different levels of gelatinase expression were studied. Moreover, the cytotoxicity study on the primary cancer cells isolated from pericardial fluids from a patient with late-stage lung cancer was conducted.

RESULTS

The Gel-NPs aggregated in response to gelatinases, which was confirmed macroscopically and microscopically. The cellular uptake amount of Gel-NPs was correlated with the level of gelatinases. The in vitro antitumor effect of Gel-NPs was also correlated with the level of gelatinases and was superior to Taxotere (commercially available docetaxel) as well as the Con-NPs. The cytotoxicity study on the primary lung cancer cells also confirmed the effectiveness of Gel-NPs.

CONCLUSION

The results in this study preliminarily demonstrated the effectiveness of gelatinase-responsive targeting strategy and the prospect of this intelligent nano-drug delivery system though further studies are needed.

Overexpression of ILK1 in breast cancer associates with poor prognosis

Integrin-linked kinase 1 (ILK1), a member of the serine/threonine kinases, has been demonstrated to be associated with numerous biological and pathological processes. However, the role of ILK1 in breast cancer has not been thoroughly elucidated. The purpose of this study was to assess ILK1 expression and to explore its contribution to breast cancer. The ILK1 mRNA expression was measured by real-time quantitative reverse transcriptase-polymerase chain reaction. In addition, ILK1 expression was analyzed by immunohistochemistry in 163 clinicopathologically characterized breast cancer cases. The relationship between ILK1 expression and clinicopathological features was analyzed by appropriate statistics. Kaplan-Meier analysis and Cox proportional hazard regression models were used to investigate the correlation between ILK1 expression and prognosis of breast cancer patients. The relative mRNA expression of ILK1 was significantly higher in breast cancer tissues than in adjacent noncancerous tissues (P < 0.001). In addition, ILK1 expression was significantly correlated with tumor size (P = 0.016), grade (P = 0.024), stage (P = 0.029), lymph node metastases (P = 0.007), and estrogen receptor status (P = 0.002). Kaplan-Meier analysis indicated that patients with high ILK1 expression had poor overall survival (P < 0.001). Multivariate analysis showed that high ILK1 expression was an independent predictor of overall survival. In conclusion, our data suggest for the first time that the increased expression of ILK1 in breast cancer is associated significantly with aggressive progression and poor prognosis. ILK1 may be an important molecular marker for predicting the carcinogenesis, progression, and prognosis of breast cancer.

Epithelial-to-mesenchymal transition: immunohistochemical investigation of related molecules in canine cutaneous epithelial tumours

BACKGROUND

Epithelial-to-mesenchymal transition (EMT) is a multistep process, important in tumour invasion and metastasis, characterized by loss of epithelial markers, redistribution of β-catenin and gain of mesenchymal markers. HYPOSTHESIS/OBJECTIVES: Our aim was to investigate the immunohistochemical aberrant expression of cytokeratin, vimentin, survivin and heat shock protein 72 (Hsp72) in canine cutaneous epithelial tumours, to understand the association of expression of these molecules with features of malignancy and their role in the EMT phenotype.

METHODS

Ten canine squamous cell carcinomas (SCCs; one with lymph node metastasis), 30 canine hair follicle tumours (six pilomatricomas, eight infundibular keratinizing acanthomas, six trichoepitheliomas and 10 trichoblastomas) and five normal skin samples were investigated by immunohistochemistry using specific anti-vimentin, -cytokeratin, -survivin and -Hsp72 antibodies. A semi-quantitative method was used to analyse the results, as follows: 0 to <5%; ≥ 5 to <10%; ≥ 10 to <25%; and ≥ 25% of positive cells. Immunofluorescence was performed to investigate survivin-vimentin and survivin-Hsp72 colocalization in selected SCCs. Results - In malignant hair follicle tumours and SCCs, a reduced intensity of cytokeratin and increased survivin and Hsp72 expression were observed. In SCCs, loss of cytokeratin expression and vimentin immunolabelling, suggestive of the EMT phenotype, were evident in <5% of neoplastic cells in the front of tumour invasion. In the same areas, strong nuclear survivin and cytoplasmic Hsp72 staining was evident, often colocalizing. Only a few neoplastic cells in the front of tumour invasion showed vimentin-survivin colocalization.

CONCLUSIONS AND CLINICAL IMPORTANCE

A possible simultaneous involvement of survivin and Hsp72 in tumour invasion and the multistep process of EMT of cutaneous epithelial tumours of dogs is suggested.

CD44 is associated with the aggressive phenotype of nasopharyngeal carcinoma through redox regulation

Recent studies have shown that cancer stem-like cells (CSCs) within a tumor have the capacity for self-renewal and differentiation, and are associated with an aggressive phenotype and therapeutic resistance. Studies have also associated tumor progression with alterations in the levels of intracellular reactive oxygen species (ROS). In this study, we cultured nasopharyngeal carcinoma (NPC) CSCs in conditions that allowed sphere formation. The resulting sphere cells displayed stemness properties, characteristics of the epithelial–mesenchymal transition (EMT), and increased expression of the CSC surface marker CD44. We further evaluated the association between CD44 expression and EMT marker expression, and any correlation with redox status, in these CSCs. We showed that the EMT in sphere cells is associated with the upregulation of CD44 expression and increased ROS generation, which might promote NPC aggressiveness. We also identified the coexpression of CD44 with the EMT marker N-cadherin in sphere cells, and downregulated CD44 expression after the addition of the antioxidant N-acetyl cysteine. Our results indicate that CD44 plays a role in the EMT phenotype of CSCs in NPC, and suggest its involvement in EMT-associated ROS production. These findings might facilitate the development of a novel therapy for the prevention of NPC recurrence and metastasis.

The impact of L-type amino acid transporter 1 (LAT1) in human hepatocellular carcinoma

Upregulation of L-type amino acid transporter 1 (LAT1) has been reported to be associated with a poor prognosis in a variety of malignant tumors. However, the impact of LAT1 in hepatocellular carcinoma (HCC) remains unclear. The objective of this study was to investigate whether the expression of LAT1 in HCC was associated with established clinicopathological features. Quantitative reverse transcription polymerase chain reaction was used to detect LAT1 mRNA expression in 23 pairs of fresh-frozen HCC tissues and corresponding noncancerous tissues. Results showed that LAT1 mRNA expression level in HCC tissues was significantly higher than that in corresponding noncancerous tissues. To investigate the association between LAT1 protein expression and clinicopathological characteristics of HCC, immunohistochemistry was performed in 148 archived paraffin-embedded HCC samples. High LAT1 expression in HCC was associated significantly with tumor size (P = 0.032), histological differentiation (P = 0.003), and tumor stage (P = 0.01). Kaplan-Meier curves demonstrated that patients with a high expression of LAT1 have a significantly increased risk of shortened survival time. Moreover, stepwise Cox regression showed that LAT1 expression may be an independent prognostic factor. Collectively, our study demonstrated that LAT1was overexpressed in HCC and could be served as a potential prognostic marker.

Clinicopathological and prognostic significance of myofibrillogenesis regulator-1 protein expression in pancreatic ductal adenocarcinoma

Myofibrillogenesis regulator-1 (MR-1) expression was detected in different malignancies and is associated with poor prognosis. However, its role in pancreatic ductal adenocarcinoma (PDAC) has not been fully elucidated. Thus, the aim of this study was to investigate the association of MR-1 expression with clinicopathologic features and prognosis in patients with PDAC. Immunohistochemistry was performed to investigate the protein expression of MR-1 and epithelial (E)-cadherin in 87 patients with PDAC. Results showed that MR-1 expression was correlated with histologic grade, tumor stage, and lymph node metastasis (all P <0.05). In addition, MR-1 expression showed a significant inverse correlation with E-cadherin expression (P = 0.002). Furthermore, the variables associated with prognosis were analyzed by Cox's proportional hazards model. Kaplan-Meier analysis was used to plot survival curves according to different expression levels of MR-1. Kaplan-Meier analysis revealed that MR-1 expression was significantly associated with worse disease-free survival (DFS) and overall survival (OS) rates in patients with PDAC (both P <0.001). Finally, multivariate analysis demonstrated that MR-1 expression, together with histologic grade, tumor stage, lymph node metastasis, was an independent prognostic factor for both DFS and OS rates in patients with PDAC. MR-1 overexpression was tightly associated with more aggressive tumor behavior and a poor prognosis, indicating that MR-1 is a valuable molecular biomarker for PDAC progression.

Tumor microenvironment profoundly modifies functional status of macrophages: peritoneal and tumor-associated macrophages are two very different subpopulations

Macrophages are key players in the inflammatory response. In this study, we tested the hypothesis that although all macrophage subpopulations in tumor hosts are affected by the disease, it is the close proximity to the tumor that induces major alterations in these cells. We compared tumor-associated macrophages (TAMs) with peritoneal macrophages from mice bearing D1-DMBA-3 mammary tumors (T-PEMs). Our results show that TAMs downregulate IL-12p70 but upregulate IL-12p40, IL-23, IL-6 and IL-10. Some NFκB and C/EBP transcription factors family members are decreased in TAMs; however NFκBp50 homodimers, STAT1/pSTAT1 and STAT3/pSTAT3 are overexpressed. Furthermore, while TAMs block T-cell proliferation and are more prone to apoptosis compared to T-PEMs, both types of macrophages have an impaired phagocytic capacity. Moreover, TAMs constitutively express iNOS and produce nitric oxide but do not express arginase and are Gr-1(high) and CD11b(low). Collectively, our analysis of two spatially distinct macrophage subpopulations in tumor-bearing mice revealed that the tumor modulates them differently into two molecularly and functionally dissimilar macrophage subpopulations.

Molecular culprits generating brain tumor stem cells

Despite current advances in multimodality therapies, such as surgery, radiotherapy, and chemotherapy, the outcome for patients with high-grade glioma remains fatal. Understanding how glioma cells resist various therapies may provide opportunities for developing new therapies. Accumulating evidence suggests that the main obstacle for successfully treating high-grade glioma is the existence of brain tumor stem cells (BTSCs), which share a number of cellular properties with adult stem cells, such as self-renewal and multipotent differentiation capabilities. Owing to their resistance to standard therapy coupled with their infiltrative nature, BTSCs are a primary cause of tumor recurrence post-therapy. Therefore, BTSCs are thought to be the main glioma cells representing a novel therapeutic target and should be eliminated to obtain successful treatment outcomes.

Aldehyde dehydrogenase 1, a functional marker for identifying cancer stem cells in human nasopharyngeal carcinoma

Aldehyde dehydrogenase 1 (ALDH1) activity has now been employed successfully as a cancer stem cells (CSCs) marker in various tumors. We wanted to investigate whether ALDH1 can be used as a putative CSCs marker and a powerful prognostic factor in nasopharyngeal carcinoma (NPC). Here, we isolated ALDH1-positive cells from human NPC cell lines (5-8F and CNE2) and found that ALDH1-positive cancer cells grew faster and had higher clone formation efficiency (0.435±0.15; 0.431±0.025 vs. 0.131±0.007; 0.121±0.126), differentiation capability and had higher migration (233.00±5.29; 228.60±9.34 vs. 123.20±7.70 vs. 97.20±6.61) than those of ALDH1-negative cancer cells in vitro. In addition, ALDH1- positive cancer cells formed significantly more tumor spheres. Our in vivo experiments showed that only 5×10(3) ALDH1-positive NPC cells were required to induce tumors. Notably, ALDH1-positive cells are enriched in the side-population (SP) cells, and stem cells-like genes OCT4, BMI1, KLF4 and SOX2 are preferentially expressed in ALDH1-positive cells. Immunohistochemical results showed that the expression of ALDH1 correlated significantly with T classification (P=0.011), N classification (P=0.005), M classification (P=0.002) and clinical stage (P=0.001). Interestingly, ALDH1 expression in the tumor correlated significantly with epithelial-mesenchymal transition (EMT) markers including vimentin expression and loss of E-cadherin (P=0.003 and 0.008, respectively). Furthermore, multivariate analyses showed that ALDH1 expression was an independent prognostic indicator (P=0.032). Taken together, for the first time, we demonstrate that ALDH1 could be a novel stem cells marker and a valuable predictor of poor survival NPC.

Artemether combined with shRNA interference of vascular cell adhesion molecule-1 significantly inhibited the malignant biological behavior of human glioma cells

Artemether is the derivative extracted from Chinese traditional herb and originally used for malaria. Artemether also has potential therapeutic effects against tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we investigated the role and mechanism of artemether combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion and apoptosis of glioma cells. U87 human glioma cells were treated with artemether at various concentrations and shRNA interfering technology was employed to silence the expression of VCAM-1. Cell viability, migration, invasiveness and apoptosis were assessed with MTT, wound healing, Transwell and Annexin V-FITC/PI staining. The expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and phosphorylated Akt (p-Akt) was checked by Western blot assay. Results showed that artemether and shRNA-VCAM-1 not only significantly inhibited the migration, invasiveness and expression of MMP-2/9 and p-Akt, but also promoted the apoptosis of U87 cells. Combined treatment of both displayed the maximum inhibitory effects on the malignant biological behavior of glioma cells. Our work revealed the potential therapeutic effects of artemether and antiVCAM-1 in the treatments of gliomas.

Inverse correlation between Naa10p and MMP-9 expression and the combined prognostic value in breast cancer patients

To analyze the expression profiles of N-a-acetyltransferase 10 protein (Naa10p/ARD1) and matrix metalloproteinase 9 (MMP-9) in human breast cancer and evaluate their possible prognostic values in breast cancer patients. Quantitative RT-PCR was used to evaluate mRNA expression of Naa10p and MMP-9 in 55 cases of fresh breast cancer tissues, and immunohistochemistry was performed for detecting Naa10p and MMP-9 proteins on breast cancer with tissue microarray containing 80 specimens. Furthermore, Naa10p and MMP-9 were measured in 253 breast cancer tissues from patients with up to 15-year follow-up. Survival curves were generated using the Kaplan-Meier method. Multivariate analysis was performed by using the Cox proportional hazard regression model to assess the prognostic values of Naa10p and MMP-9. Both Naa10p and MMP-9 expression in breast cancer tissues were significantly higher than those in the matched non-cancerous tissues (p = 0.000 for both). There was an inverse correlation between Naa10p and MMP-9 expression at mRNA and protein levels (p = 0.000 for both). Patients with MMP-9- positive expression had a poorer overall survival (OS) and disease-free survival (DFS) than those with MMP-9-negative expression (p = 0.001 for both). However, patients with Naa10p-positive expression had better OS and DFS (p = 0.000 for both). In addition, Naa10p-positive/MMP-9- negative patients had the best OS and DFS (p = 0.000 for both). In multivariate survival analysis, TNM stage, Naa10p expression, MMP-9 expression, and combined expression status of Naa10p/MMP-9 were independent prognostic factors related to OS (p = 0.000, 0.007, 0.012, and 0.000, respectively) and DFS (p = 0.000, 0.002, 0.014, and 0.000, respectively).The expression level of Naa10p was inversely correlated with that of MMP-9 in human breast cancer samples. Combined analysis of Naa10p and MMP-9 had a significantly increased value for determining the prognosis of breast cancer patients.

Overexpression of ARK5 is associated with poor prognosis in hepatocellular carcinoma

ARK5 overexpression has been reported in a variety of human cancers. However, the role of ARK5 in hepatocellular carcinoma (HCC) remains unclear. The aim of the present study is to analyze the ARK5 protein expression in HCC tissue samples and to assess its prognostic significance for HCC. ARK5 mRNA and protein expression were determined by real-time quantitative reverse transcriptase-polymerase chain reaction and Western blot in 20 pairs of fresh frozen HCC tissues and corresponding non-cancerous tissues. In addition, ARK5 expression was analyzed by immunohistochemistry in 130 clinicopathologically characterized HCC cases. The correlation of ARK5 expression with patients' survival rate was assessed by Kaplan-Meier and Cox regression. Our results showed that the expression levels of ARK5 mRNA and protein in HCC tissues were both significantly higher than those in non-cancerous tissues. Our results showed that the high expression of ARK5 in HCC was related to tumor size (p=0.005), histological differentiation (p=0.047), and tumor stage (p=0.005). Kaplan-Meier survival analysis showed that a high expression level of ARK5 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that ARK5 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. In conclusion, ARK5 might play a positive role in tumor development and could serve as an independent predictor of poor prognosis for HCC.

ADAM17 is overexpressed in non-small cell lung cancer and its expression correlates with poor patient survival

The purpose of this study was to assess ADAM17 expression and to explore its contribution to the non-small cell lung cancer (NSCLC). Real-time quantitative reverse transcriptase-polymerase chain reaction was conducted to detect ADAM17 mRNA expression. In addition, ADAM17 expression was analyzed by immunohistochemistry in 124 clinicopathologically characterized NSCLC cases. The correlation of ADAM17 expression with patients' survival rate was assessed by Kaplan-Meier and Cox regression. The expression levels of ADAM17 mRNA and protein in NSCLC tissues were both significantly higher than those in non-cancerous tissues. In addition, high expression of ADAM17 was significantly correlated with tumor grade (P=0.026), tumor size (P=0.001), clinical stage (P=0.016), and lymph node metastases (P<0.001). Furthermore, multivariate analysis suggested that tumor grade, tumor size, clinical stage, lymph node metastases, and ADAM17 expression were independent prognostic indicators for NSCLC. Our data suggest for the first time that the increased expression of ADAM17 in NSCLC is associated significantly with aggressive progression and poor prognosis. ADAM17 may be an important molecular marker for predicting the carcinogenesis, progression, and prognosis of NSCLC.

Cancer stem cell contribution to glioblastoma invasiveness

Glioblastoma (GBM) is the most aggressive and lethal brain tumor in adults. Its invasive nature currently represents the most challenging hurdle to surgical resection. The mechanism adopted by GBM cells to carry out their invasive strategy is an intricate program that recalls what takes place in embryonic cells during development and in carcinoma cells during metastasis formation, the so-called epithelial-to-mesenchymal transition. GBM cells undergo a series of molecular and conformational changes shifting the tumor toward mesenchymal traits, including extracellular matrix remodeling, cytoskeletal re-patterning, and stem-like trait acquisition. A deeper understanding of the mechanisms driving the whole infiltrative process represents the first step toward successful treatment of this pathology. Here, we review recent findings demonstrating the invasive nature of GBM cancer stem cells, together with novel candidate molecules associated with both cancer stem cell biology and GBM invasion, like doublecortin and microRNAs. These findings may affect the design of effective therapies currently not considered for GBM invasive progression.

Deuterium-depleted water (DDW) inhibits the proliferation and migration of nasopharyngeal carcinoma cells in vitro

Recent studies have demonstrated that natural water that has 65% of the deuterium concentration depleted, can exhibit anti-tumor properties. However, the anti-tumor effects of DDW on various nasopharyngeal carcinoma (NPC) cells have not previously been reported. In the present study, NPC cell lines and normal preosteoblast MC3T3-E1 cells were grown in RPMI1640 media containing different deuterium concentrations (50-150 ppm). The effects of DDW on the proliferation and migration of NPC and MC3T3-E1 cells were investigated using the MTT, plate colony formation, and Transwell assays, as well as Boyden chamber arrays, flow cytometry (FCM), western blot and immunofluorescence. We found that DDW was an effective inhibitor of NPC cell proliferation, plated colony formation, migration and invasion. In contrast, the growth of normal preosteoblast MC3T3-E1 cells was promoted when they were cultured in the presence of DDW. Cell cycle analysis revealed that DDW caused cell cycle arrest in the G1/S transition, reduced the number of cells in the S phase and significantly increased the population of cells in the G1 phase in NPC cells. Western blot analysis revealed that treatment with DDW significantly increased the expression of NADPH:quinone oxidoreductase-1 (NQO1), while immunofluorescence assay analysis revealed that treatment with DDW decreased the expression of PCNA and matrix metalloproteinase 9 (MMP9) in NPC cells. These results demonstrated that DDW is a novel, non-toxic adjuvant therapeutic agent that suppresses NPC cell proliferation, migration, and invasion by inducing the expression of NQO1 and causing cell cycle arrest, as well as decreasing PCNA and MMP9 expression.

Matrix metalloproteinase and its drug targets therapy in solid and hematological malignancies: an overview

Matrix metalloproteinase (MMP) comprises a family of zinc-dependent endopeptidases that degrade various components of the extracellular matrix (ECM) and basement membrane. MMPs are involved in solid and hematological malignancy through modification of cell growth, activation of cancer cells and modulation of immune functions. Several polymorphisms of different MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A) & MMP-9 (-1562 C/T) and their expression levels have been well documented in different types of solid cancer. These polymorphic variations were found to be associated with angiogenesis, cancer progression, invasion and metastasis. There is paucity of data available in the field of hematological malignancies. Hence the field of matrix biology of hematological malignancies is an area of active exploration. A number of MMP inhibitors (MMPIs) have been developed for the cancer treatment. The most extensively studied classes of MMP inhibitors include Batimastat, Marismastat, Salimatat, Prinomastat and Tanomastat. However, their efficacy and action have not been confirmed and more data is required. The application of one or more selective targeted MMPIs in combination with conventional anti-leukemic treatment may represent a positive approach in combat against hematopoietic malignancies. Balance of MMPs and TIMPs is altered in different malignancies and biochemical pathways. These alternations will add another dimension in the matrix biology of both solid tumor and leukemia. MMP and TIMP singly and in combination are increasingly being recognized as an important player in basic cellular biology. Exploration and exploitation of MMP and TIMP balance in various malignant and nonmalignant lesions is going to be one of the most interesting facets of future use of this system for human health care.

EIF4E over-expresses and enhances cell proliferation and cell cycle progression in nasopharyngeal carcinoma

Eukaryotic translation initiation factor 4E (eIF4E) is involved in integration and amplification of many carcinogenesis signals in tumors. However, it remains unclear whether eIF4E over-expresses in NPC and whether it is associated with the development of NPC. Here, we analyzed the expression state of eIF4E, c-Myc, and MMP9 in 24 nasopharyngitises and 64 nasopharyngeal carcinomas (NPC) tissues and studied the influences of eIF4E on the proliferation and cell cycle in NPC cell lines. The results indicate that eIF4E might over-express in NPC and the over-expression of eIF4E promotes NPC growth and cell cycle progression through enhancing the translational expression of c-Myc and MMP9. The finding certainly adds new knowledge in the understanding of the carcinogenesis of NPC and provides a potential molecular target for the NPC therapy and prevention.

Embryonic stem cells markers SOX2, OCT4 and Nanog expression and their correlations with epithelial-mesenchymal transition in nasopharyngeal carcinoma

Expression of embryonic stem cells (ESCs) markers (SOX2, OCT4, Nanog and Nestin) is crucial for progression of various human malignancies. The purpose of this study was to investigate the expression and prognostic impact of these molecules in nasopharyngeal carcinoma (NPC) patients by immunohistochemistry and immunofluorescence. In the present study, we found that the expression levels of SOX2, OCT4 and Nanog were highly expressed in NPC compared with the non-tumorous tissues. Furthermore, these proteins correlated significantly with several clinicalpathological factors and epithelial-mesenchymal transition (EMT)-associated indicators (E-cadherin/N-cadherin and Snail). In multivariate analyses, high expression of OCT4 (P = 0.013) and Nanog (P = 0.040), but not that of SOX2, was associated with worse survival and had strongly independent prognostic effects. Of note, OCT4 and Nanog were more frequently located at the invasive front of tumors, and correlated significantly with various aggressive behaviors including T classification, N classification, M classification and clinical stage. Furthermore, patients with co-expression of OCT4 and Nanog in the invasive front had significantly worse survival (P = 0.005). Interestingly, at the invasive front, these molecules correlated significantly with Nestin expression in endothelial cells (P<0.001). These findings provide evidence that ESCs biomarkers OCT4 and Nanog serves as independent prognostic factors for NPC. Additionally, cancer cells in the invasive front of NPC acquiring ESCs-like features should be maintained by vascular niches.

Molecular characterization and clinical implications of spindle cells in nasopharyngeal carcinoma: a novel molecule-morphology model of tumor progression proposed

Up to now, the precise molecular and morphological changes underlying the invasive and metastatic properties of nasopharyngeal carcinoma (NPC) remain largely unresolved. We speculate that neoplastic spindle cells, which are prominently found in the invasive tumor front and the surrounding stroma, might be responsible for the aggressive patterns. Expression profiling of various biomarkers relevant to cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT) was performed by tissue microarray-based immunohistochemistry in NPC samples. The expression of EBER and LMP1 was detected by in situ hybridization and immunohistochemistry, respectively. We found that overexpression of CSCs-related markers (ALDH1, Nanog and ABCG2) and up-regulation of EMT markers (Fibronectin, MMP-2, Periostin, SPARC, Snail and Slug), together with E- to N-cadherin switching, occurred preferentially in tumors containing a large proportion of spindle-shaped malignant cells. Furthermore, CSCs-like properties were highly present in spindle cells compared with non-spindle cells of tumors, and correlated strongly with EMT features. In addition, EBV-related factors EBER and LMP1 were highly expressed and correlated strongly with CSCs and EMT characteristics in neoplastic spindle cells. Importantly, high proportion of spindle cells (≥20%) correlated significantly with various aggressive aspects including lymph node metastasis (P = 0.031) and local recurrence (P = 0.014). Patients with high proportion of spindle cells had poor survival (P = 0.004), though it was not an independent value. In conclusion, we demonstrate that spindle cells could be valuable morphological indicators of tumor progression and unfavorable prognosis of NPC. An integrated molecule-morphology model of NPC firstly constructed may shed significant light on the metastatic cascade and clinical relevance of patients.

Epithelial-to-mesenchymal(-like) transition as a relevant molecular event in malignant gliomas

Tumor dissemination and metastatic behavior account for the vast majority of cancer associated mortality. Epithelial tumors achieve this progressive state via epithelial-to-mesenchymal transition (EMT); however, the importance of this process in the neuroepithelial context is currently very controversially discussed. The review describes the current research status concerning EMT-like changes in malignant gliomas including the role of TWIST1, ZEB1/ZEB2 and SNAIl1/SNAIl2 as inducers for cell-invasiveness in GBMs. Furthermore, WNT/β-catenin signaling with its key-component FRIZZLED4 activating an EMT-like program in malignant gliomas and its relationship to the stem-like phenotype as well as discoveries on micro-RNA-level regulating the EMT-like process are discussed.

High expression of CD147 and MMP-9 is correlated with poor prognosis of triple-negative breast cancer (TNBC) patients

The aim of this study was to investigate expression of CD147 and MMP-9 in triple-negative breast cancer (TNBC) so as to determine whether these two proteins may be correlated with poor prognosis of TNBC patients. We examined the expression levels of the CD147 and MMP-9 in 127 patients with TNBC and 30 patients with mammary gland fibroma using immunohistochemical staining before any treatments. Furthermore, we analyzed the correlation between the expression of these two proteins and various clinicopathologic factors including survival status of patients with TNBC. Positive stain of CD147 and MMP-9 was observed in all samples of TNBC. A statistically positive correlation was observed between the expression levels of CD147 and MMP-9 in TNBC tissues. The incidences of high expression were 48.0 % for CD147 and 53.5 % for MMP-9 in 127 TNBC tissues, respectively. High expression of either CD147 or MMP-9 was significantly correlated with clinical feature and shorter progression-free survival (PFS) (P(CD147) = 0.039; P(MMP-9) = 0.017) and overall survival (OS) (P(CD147) = 0.037; P(MMP-9) = 0.023). The expression levels of CD147 and MMP-9 are positively correlated with invasion, metastasis and shorter PFS/OS of TNBC. Patients with high expression of CD147 and MMP-9 had poor prognosis than TNBC patients with low expression.

Up-regulated miR155 reverses the epithelial-mesenchymal transition induced by EGF and increases chemo-sensitivity to cisplatin in human Caski cervical cancer cells

The epithelial-mesenchymal transition (EMT) induced by EGF promotes cervical cancer progression; however, the mechanisms underlying the EGF-induced EMT remain unclear. In this study, we reported that miR155 overexpression suppressed EGF-induced EMT, decreased migration/invasion capacities, inhibited cell proliferation and increased the chemo-sensitivity to DDP in human Caski cervical cancer cells. Further, the overexpression of miR155 increased TP53 expression but reduced SMAD2, and CCND1 expression levels. These data suggest that miR155 negatively regulates EGF-induced EMT. We conclude that miR155 does not act as an oncogene but as a tumour suppressor in Caski cells.

IGFBP7 binds to the IGF-1 receptor and blocks its activation by insulin-like growth factors

Insulin-like growth factor-binding protein 7 (IGFBP7) is a secreted factor that suppresses growth, and the abundance of IGFBP7 inversely correlates with tumor progression. Here, we showed that pretreatment of normal and breast cancer cells with IGFBP7 interfered with the activation and internalization of insulin-like growth factor 1 receptor (IGF1R) in response to insulin-like growth factors 1 and 2 (IGF-1/2), resulting in the accumulation of inactive IGF1R on the cell surface and blockade of downstream phosphatidylinositol 3-kinase (PI3K)-AKT signaling. Binding of IGFBP7 and IGF-1 to IGF1R was mutually exclusive, and the N-terminal 97 amino acids of IGFBP7 were important for binding to the extracellular portion of IGF1R and for preventing its activation. Prolonged exposure to IGFBP7 resulted in activation of the translational repressor 4E-binding protein 1 (4E-BP1) and enhanced sensitivity to apoptosis in IGF1R-positive cells. These results support a model whereby IGFBP7 binds to unoccupied IGF1R and suppresses downstream signaling, thereby inhibiting protein synthesis, cell growth, and survival.

Tumour budding and the expression of cancer stem cell marker aldehyde dehydrogenase 1 in nasopharyngeal carcinoma

AIMS

To detect the prognostic significance of tumour budding and its expression of aldehyde dehydrogenase 1 (ALDH1) in nasopharyngeal carcinoma (NPC).

METHODS AND RESULTS

Tumour budding was investigated in 105 patients with NPC by immunohistochemistry for pan-cytokeratin (AE1/AE3). The intensity of budding correlated strongly with T classification (P=0.008), lymphatic invasion (P<0.001), vascular invasion (P=0.029), lymph node metastasis (P < 0.001), and clinical stage (P=0.010). Univariate analysis revealed that patients with high budding grade had poorer survival than those with low grade (P=0.002). Multivariate analysis showed that tumour budding was an independent predictor of survival (P=0.001). Furthermore, budding cells showed high-level expression of the cancer stem cell (CSC) marker ALDH1. Budding cells with high-level ALDH1 expression contributed to several aggressive behaviours and poor survival (P=0.000).

CONCLUSIONS

  We describe, for the first time, the presence of tumour budding and its correlation with aggressive tumour behaviour and poor patient survival in NPC. The degree of tumour budding could be a valuable predictive factor in NPC. In addition, we show, also for the first time, that budding cells in NPC might possess the invasive and metastatic properties of CSCs.

GDF5 regulates TGFß-dependent angiogenesis in breast carcinoma MCF-7 cells: in vitro and in vivo control by anti-TGFß peptides

BACKGROUND

TGFß overproduction in cancer cells is one of the main characteristics of late tumor progression being implicated in metastasis, tumor growth, angiogenesis and immune response. We investigated the therapeutic efficacy of anti-TGFß peptides in the control of angiogenesis elicited by conditional over-expression of TGFß.

METHODS

We have inserted in human MCF7 mammary-cancer cells a mutated TGFß gene in a tetracycline-repressible vector to obtain conditional expression of mature TGFß upon transient transfection, evaluated the signaling pathways involved in TGFß-dependent endothelial cells activation and the efficacy of anti-TGFß peptides in the control of MCF7-TGFß-dependent angiogenesis.

RESULTS

TGFß over-expression induced in MCF7 several markers of the epithelial-to-mesenchymal transition. Conditioned-medium of TGFß-transfected MCF7 stimulated angiogenesis in vivo and in vitro by subsequent activation of SMAD2/3 and SMAD1/5 signaling in endothelial cells, as well as SMAD4 nuclear translocation, resulting in over-expression of the pro-angiogenic growth and differentiation factor-5 (GDF5). Inhibition or silencing of GDF5 in TGFß-stimulated EC resulted in impairment of GDF5 expression and of TGFß-dependent urokinase-plasminogen activator receptor (uPAR) overproduction, leading to angiogenesis impairment. Two different TGFß antagonist peptides inhibited all the angiogenesis-related properties elicited in EC by exogenous and conditionally-expressed TGFß in vivo and in vitro, including SMAD1/5 phosphorylation, SMAD4 nuclear translocation, GDF5 and uPAR overexpression. Antagonist peptides and anti-GDF5 antibodies efficiently inhibited in vitro and in vivo angiogenesis.

CONCLUSIONS

TGFß produced by breast cancer cells induces in endothelial cells expression of GDF5, which in turn stimulates angiogenesis both in vitro and in vivo. Angiogenesis activation is rapid and the involved mechanism is totally opposed to the old and controversial dogma about the AKL5/ALK1 balance. The GDF-dependent pro-angiogenic effects of TGFß are controlled by anti-TGFß peptides and anti-GDF5 antibodies, providing a basis to develop targeted clinical studies.

Prognostic significance of BMP7 as an oncogene in hepatocellular carcinoma

This study aims to evaluate the association between BMP7 tissue expression and patient prognosis in hepatocellular carcinoma (HCC). The expression of BMP7 mRNA in HCC was characterized using real-time PCR and 30 pairs of fresh frozen HCC tissues and corresponding noncancerous tissues. BMP7 protein expression in HCC was confirmed using immunohistochemistry on a tissue microarray chip. Finally, BMP7 expression was correlated with conventional clinicopathological features of HCC and patient outcome. The expression of BMP7 mRNA and protein in HCC cells was much higher than in normal hepatic cells. Our results showed that the high expression of BMP7 in HCC was related to tumor size (p < 0.001), histological differentiation (p = 0.041), serum AFP (p = 0.007), and tumor stage (p < 0.001). Kaplan-Meier survival analysis showed that a high-expression level of BMP7 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that BMP7 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that a high-expression level of BMP7 serves as a biomarker for poor prognosis for HCC. Thus, we speculate that BMP7 may be a potential target of antiangiogenic therapy for HCC.

Overexpression of GOLPH3 is associated with poor clinical outcome in gastric cancer

This study aims to investigate the expression and significance of GOLPH3 in human gastric cancer progression and prognosis. Using immunohistochemistry (IHC) and real-time reverse transcriptase polymerase chain reaction assay, we identified abnormally elevated expression of GOLPH3 in gastric cancer tissues compared to paired normal stomach mucosa tissues in 40 patients. In addition, the enzyme-linked immunosorbent assay (ELISA) was used to quantify serum GOLPH3 concentrations in the same 40 gastric cancer patients and 40 healthy individuals. ELISA revealed significantly higher serum concentrations of GOLPH3 in gastric cancer patients compared to healthy individuals (p = 0.002). In order to investigate the correlations between GOLPH3 and the clinicopathological features of gastric cancer, the expression of GOLPH3 in 123 gastric cancer patients were detected by IHC, and the results showed that overexpression of GOLPH3 was associated with the size of the tumor (p = 0.013), histological grade (p = 0.002), depth of invasion (p < 0.001), lymph node metastasis (p < 0.001), distant metastasis (p = 0.018), and TNM stage (p < 0.001). Kaplan-Meier survival analysis showed that high GOLPH3 expression exhibited a significant correlation with poor prognosis for gastric cancer patients. Further, Cox multivariate analysis indicated that GOLPH3 expression level was an independent prognostic factor for patients after radical resection. In conclusion, the overexpression of GOLPH3 is closely related to the progression of gastric cancer and might be regarded as an independent predictor of poor prognosis for gastric cancer.

Epigallocathechin gallate, polyphenol present in green tea, inhibits stem-like characteristics and epithelial-mesenchymal transition in nasopharyngeal cancer cell lines

BACKGROUND

Previous studies have demonstrated that the consumption of green tea inhibits the growth of various cancers. Most cancers are believed to be initiated from and maintained by a small population of cancer stem-like cells (CSC) or tumor-initiating cells (TIC) that are responsible for tumor relapse and chemotherapeutic resistance. Although epigallocathechin gallate (EGCG), the most abundant catechin in green tea, has been reported to induce growth inhibition and apoptosis in some cancer cells, its effect on CSC is undefined. In this study, we enriched CSC by the sphere formation, and provided an efficient model for further experiments. Using this method, we examined the effects of EGCG regulating the nasopharyngeal carcinoma (NPC) CSC and attempted to elucidate the possible mechanisms.

METHODS

NPC TW01 and TW06 cell lines were enriched by sphere formation and characterized their phenotypical properties, such as invasion capacity, epithelial-mesenchymal transition (EMT) and gene expression were analyzed by quantitative real-time reverse transcription polymerase chain reaction (q-RT-PCR). EGCG-induced growth inhibition in the parental and sphere-derived cells was determined by MTT and bromodeoxyuridine (BrdU) assay. EGCG-induced apoptosis was analyzed by flow cytometry with Annexin V and PI staining. The effects of EGCG on sphere-derived cell tumorigenicity, migration and invasion were determined by soft agar assay, wound healing, and cell invasion assay. The alternation of protein expression regulated by EGCG on these sphere-derived cells was assessed by immunofluorescence staining and western blot.

RESULTS

NPC sphere-derived cells grown in serum-free non-adherent culture showed increased expression of stem cell markers and EMT markers compared to parental cells grown in conventional culture. Although EGCG induced growth inhibition and apoptosis in the parental cells in a dose-dependent manner, it was not as effective against spheres. However, EGCG potently inhibited sphere formation and can eliminate the stem cell characteristics of NPC and inhibit the epithelial-mesenchymal transition (EMT) signatures.

CONCLUSIONS

Overall, these findings show that NPC cells with sphere formations possess the properties of CSC. Using this model, we found that EGCG regulated NPC CSC, their self-renewal capacity, and inhibited their invasive characteristics. It supports the pivotal role of EGCG as a dietary compound targeting NPC and may decrease recurrence and metastasis in nasopharyngeal carcinoma cells.

Effect of alendronate sodium on the expression of mesenchymal-epithelial transition markers in mice with liver fibrosis

The aim of this study was to explore whether alendronate sodium regulates tissue remodeling by controlling the transforming growth factor (TGF)-β1-induced epithelial-mesenchymal transition (EMT) and bone morphogenetic protein (BMP)-7-induced mesenchymal-epithelial transition (MET) in CCl₄-induced hepatic fibrosis in mice. A mouse model of CCl₄-induced hepatic fibrosis was evaluated using the hematoxylin and eosin (HE) and Masson’s trichrome staining histological methods. The activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured using an automated biochemical analyzer. The expression of TGF-β1, α-smooth muscle actin (α-SMA), BMP-7 and E-cadherin in the hepatic tissue was detected using immunohistochemistry. The mRNA and protein levels of TGF-β1, α-SMA, BMP-7, fibroblast-specific protein 1 (FSP1), E-cadherin and N-cadherin were detected using RT-PCR and western blot analysis. Immunohistochemical and molecular biochemical examination revealed that alendronate sodium significantly arrested the progression of hepatic fibrosis. Alendronate sodium caused significant amelioration of liver injury and reduced the activities of serum ALT and AST (P<0.001). Furthermore, alendronate sodium markedly reduced TGF-β1 and α-SMA mRNA expression and increased BMP-7 and E-cadherin in the mouse liver tissue (P<0.001). Alendronate sodium significantly arrested the progression of hepatic fibrosis. The underlying mechanism was associated with changes in the redox state, which remains variable in liver fibrosis, and depends on the balance between TGF-β/smad- and BMP-7-modulated mechanisms which regulate EMT and MET in multifunctional progenitors.

Aberrant expression of nuclear vimentin and related epithelial-mesenchymal transition markers in nasopharyngeal carcinoma

Expression of vimentin and the epithelial to mesenchymal transition (EMT) markers E-cadherin, β-catenin is essential for the progression of various human cancers. Our study aimed to investigate the aberrant localization E-cadherin, β-catenin and vimentin, and their prognostic significance in 122 nasopharyngeal carcinoma (NPC) patients by immunohistochemistry and immunofluorescence. Our results showed that both membranous and cytoplasmic localization of E-cadherin staining were associated with lymph node metastasis (p = 0.000 and 0.005, respectively) and clinical stage (p = 0.000 and 0.007, respectively). High cytoplasmic β-catenin correlated significantly with larger tumor size (p = 0.020), lymph node metastasis (p = 0.000) and advanced clinical stage (p = 0.036). However, no significant difference was observed between membranous β-catenin and clinicopathologic features (p ≥ 0.05). High nuclear vimentin expression correlated significantly with positive lymph node metastasis (p = 0.000) and advanced clinical stage (p = 0.000). Multivariate analysis showed that nuclear vimentin and cytoplasmic E-cadherin were independent prognostic factors (p = 0.016 and 0.001, respectively), as well as M classification (p = 0.001). More importantly, patients with high coexpression of nuclear vimentin and cytoplasmic E-cadherin had shorter survival time (p = 0.000). Furthermore, high coexpression of these two proteins was closely associated with lymph node metastasis (p = 0.000) and advanced clinical stage (p = 0.000). Our studies provide convincing evidence that EMT may play an important role in the biological progression of NPC, and nuclear vimentin and cytoplasmic E-cadherin might have independent prognostic value in NPC patients and serve as novel targets for prognostic therapeutics.

High expression of AP-4 predicts poor prognosis for hepatocellular carcinoma after curative hepatectomy

The aim of this study was to evaluate the association between activating enhancer binding protein 4 (AP-4) tissue expression and patient prognosis in hepatocellular carcinoma (HCC). The levels of AP-4 mRNA and protein in tumor and para-tumor tissue were evaluated in 30 HCC cases by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Additionally, AP-4 protein expression in 112 HCC was analyzed by immunohistochemistry. The correlation of AP-4 expression and patients' clinicopathological parameters was evaluated. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. By RT-PCR and Western blot, the levels of AP-4 mRNA and protein were significantly higher in HCC, compared to that in para-tumor tissue (p < 0.001). Immunohistochemical staining revealed that AP-4 was highly expressed in 53.6 % of the HCC patients. The AP-4 expression level was closely associated with serum alpha fetoprotein elevation, tumor size, histological differentiation, tumor recurrence, tumor metastasis, and tumor stage. Kaplan-Meier survival analysis showed that a high expression level of AP-4 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that AP-4 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that a high expression level of AP-4 serves as a biomarker for poor prognosis for HCC. Thus, we speculate that AP-4 may be a potential target of antiangiogenic therapy for HCC.

Migfilin sensitizes cisplatin-induced apoptosis in human glioma cells in vitro

AIM

Filamin binding LIM protein 1, also known as migfilin, is a skeleton organization protein that binds to mitogen-inducible gene 2 at cell-extracellular matrix adhesions. The aim of this study was to investigate the role of migfilin in cisplatin-induced apoptosis in human glioma cells, to determine the functional domains of migfilin, and to elucidate the molecular mechanisms underlying the regulation of cisplatin-related chemosensitivity.

METHODS

The human glioma cell lines Hs683, H4, and U-87 MG were transfected with pEGFP-C2-migfilin to elevate the expression level of migfilin. RNA interference was used to reduce the expression of migfilin. To determine the functional domains of migfilin, U-87 MG cells were transfected with plasmids of migfilin deletion mutants. After treatment with cisplatin (40 μmol/L) for 24 h, the cell viability was assessed using the MTS assay, and the cell apoptotic was examined using the DAPI staining assay and TUNEL analysis. Expression levels of apoptosis-related proteins were detected by Western blot analysis.

RESULTS

Overexpression of migfilin significantly enhanced cisplatin-induced apoptosis in Hs683, H4, and U-87 MG cells, whereas downregulation of migfilin expression inhibited the chemosensitivity of these cell lines. The N-terminal region of migfilin alone was able to enhance the cisplatin-induced apoptosis. However, despite the existence of the N-terminal region, mutants of migfilin with any one of three LIM domains deleted led to a function loss. Furthermore, apoptotic proteins (PARP and caspase-3) and the anti-apoptotic protein Bcl-xL were modulated by the expression level of migfilin in combination with cisplatin.

CONCLUSION

The LIM1-3 domains of migfilin play a key role in sensitizing glioma cells to cisplatin-induced apoptosis through regulation of apoptosis-related proteins.

In vitro cell migration and invasion assays

Determining the migratory and invasive capacity of tumor and stromal cells and clarifying the underlying mechanisms is most relevant for novel strategies in cancer diagnosis, prognosis, drug development and treatment. Here we shortly summarize the different modes of cell travelling and review in vitro methods, which can be used to evaluate migration and invasion. We provide a concise summary of established migration/invasion assays described in the literature, list advantages, limitations and drawbacks, give a tabular overview for convenience and depict the basic principles of the assays graphically. In many cases particular research problems and specific cell types do not leave a choice for a broad variety of usable assays. However, for most standard applications using adherent cells, based on our experience we suggest to use exclusion zone assays to evaluate migration/invasion. We substantiate our choice by demonstrating that the advantages outbalance the drawbacks e.g. the simple setup, the easy readout, the kinetic analysis, the evaluation of cell morphology and the feasibility to perform the assay with standard laboratory equipment. Finally, innovative 3D migration and invasion models including heterotypic cell interactions are discussed. These methods recapitulate the in vivo situation most closely. Results obtained with these assays have already shed new light on cancer cell spreading and potentially will uncover unknown mechanisms.