Revisiting the seed and soil in cancer metastasis

Anti-angiogenesis in colorectal cancer therapy

The morbidity of colorectal cancer (CRC) has risen to third place among malignant tumors worldwide. In addition, CRC is a common cancer in China whose incidence increases annually. Angiogenesis plays an important role in the development of tumors because it can bring the nutrients that cancer cells need and take away metabolic waste. Various mechanisms are involved in the formation of neovascularization, and vascular endothelial growth factor is a key mediator. Meanwhile, angiogenesis inhibitors and drug resistance (DR) are challenges to consider when formulating treatment strategies for patients with different conditions. Thus, this review will discuss the molecules, signaling pathways, microenvironment, treatment, and DR of angiogenesis in CRC.

Nanoparticle drug delivery systems responsive to tumor microenvironment: Promising alternatives in the treatment of triple-negative breast cancer

The conventional therapeutic treatment of triple-negative breast cancer (TNBC) is negatively influenced by the development of tumor cell drug resistant, and systemic toxicity of therapeutic agents due to off-target activity. In accordance with research findings, nanoparticles (NPs) responsive to the tumor microenvironment (TME) have been discovered for providing opportunities to selectively target tumor cells via active targeting or Enhanced Permeability and Retention (EPR) effect. The combination of the TME control and therapeutic NPs offers promising solutions for improving the prognosis of the TNBC because the TME actively participates in tumor growth, metastasis, and drug resistance. The NP-based systems leverage stimulus-responsive mechanisms, such as low pH value, hypoxic, excessive secretion enzyme, concentration of glutathione (GSH)/reactive oxygen species (ROS), and high concentration of Adenosine triphosphate (ATP) to combat TNBC progression. Concurrently, NP-based stimulus-responsive introduces a novel approach for drug dosage design, administration, and modification of the pharmacokinetics of conventional chemotherapy and immunotherapy drugs. This review provides a comprehensive examination of the strengths, limitations, applications, perspectives, and future expectations of both novel and traditional stimulus-responsive NP-based drug delivery systems for improving outcomes in the medical practice of TNBC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Fucosyltransferase 3 and 8 promote the metastatic capacity of cancer stem-like cells via CD15s and E-cadherin in esophageal cancer

Objectives

Esophageal cancer stem cells (ECSCs) have been identified as the subset of cells within esophageal squamous cell carcinoma that possess tumorigenic, invasive, and metastatic properties. One important aspect of cancer metastasis is the binding of sialyl-Lewis X (CD15s) with E- or P-selectin, which facilitates the adhesion and migration of cancer cells to distant sites. This study was conducted to investigate the impact of fucosylation processes on the metastatic behavior of ECSCs.

Materials and Methods

The esophageal cancer cell line (KYSE-30) was cultured and divided into control and 2F-peracetyl fucose (2F-PerAcFuc) treated groups. Spheres were harvested from these cultures. Cell invasion assay and qPCR were conducted to examine migration and marker expression in both groups. Cancer cell line-derived xenografts were established in nude mice to validate findings in vivo.

Results

Our results initially indicated that the addition of 2F-PerAcFuc, an inhibitor of fucosylation, resulted in the down-regulation of the Fut3/CD15s pathway in both cancer stem-like cells and the xenograft model. Measurements of subcutaneous xenograft tumor volume revealed a significant decrease in tumor size among nude mice after treatment with 2F-PerAcFuc. Additionally, a reduction in Fut8/E-cadherin levels was observed in the xenograft model of nude mice. Furthermore, the administration of 2F-PerAcFuc lowered the levels of fucosylated glycoconjugates in nude mice.

Conclusion

Our data suggest that inhibition of fucosyltransferase 3 and 8 can reduce the metastatic capacity of cancer stem-like cells by down-regulating CD15s and E-cadherin in a mouse model of esophageal cancer.

'Two-faces' of hyaluronan, a dynamic barometer of disease progression in tumor microenvironment

Hyaluronan (HA) is a linear polysaccharide consisting of disaccharide units which are the D-glucuronic acid and N-acetyl-D-glucosamine. As the largest component of the extracellular matrix in microenvironment, HA polymers with different molecular weights vary in properties to molecular biology function. High molecular weight HA (HMW-HA) is mainly found in normal tissue or physiological condition, and exhibits lubrication and protection properties due to its good water retention and viscoelasticity. On the other hand, an increase in HA catabolism leads to the accumulation of low molecular weight HA (LMW-HA) under pathological circumstances such as inflammation, pre-cancerous and tumor microenvironment. LMW-HA acts as extracellular signals to enhance tumorigenic and metastatic phenotype, such as energy reprogramming, angiogenesis and extracellular matrix (ECM) remodeling. This review discusses the basic properties of this simplest carbohydrate molecule in ECM with enormous potential, and its regulatory role between tumorigenesis and microenvironmental homeostasis. The extensive discoveries of the mechanisms underlying the roles of HA in various physiological and pathological processes would provide more information for future research in the fields of biomimetic materials, pharmaceutical and clinical applications.

CircRNAs: Roles in regulating head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC), the most common head and neck malignant tumor, with only monotherapy, is characterized by poor prognosis, and low 5-year survival rate. Due to the lack of therapeutic targets, the targeted drugs for HNSCC are rare. Therefore, exploring the regulation mechanism of HNSCC and identifying effective therapeutic targets will be beneficial to its treatment of. Circular RNA (CircRNA) is a class of RNA molecules with a circular structure, which is widely expressed in human body. CircRNAs regulate gene expression by exerting the function as a miRNA sponge, thereby mediating the occurrence and development of HNSCC cell proliferation, apoptosis, migration, invasion, and other processes. In addition, circRNAs are also involved in the regulation of tumor sensitivity to chemical drugs and other biological functions. In this review, we systematically listed the functions of circRNAs and explored the regulatory mechanisms of circRNAs in HNSCC from the aspects of tumor growth, cell death, angiogenesis, tumor invasion and metastasis, tumor stem cell regulation, tumor drug resistance, immune escape, and tumor microenvironment. It will assist us in discovering new diagnostic markers and therapeutic targets, while encourage new ideas for the diagnosis and treatment of HNSCC.

G-protein subunit gamma-4 expression has potential for detection, prediction and therapeutic targeting in liver metastasis of gastric cancer

BACKGROUND

The liver is the most common site for haematogenous metastasis of gastric cancer, and liver metastasis is fatal.

METHODS

We conducted a transcriptomic analysis between metastatic foci in the liver, primary tumour and adjacent tissues from gastric cancer patients with metastasis limited to the liver. We determined mRNA expression levels in tumour tissues of 300 patients with gastric cancer via quantitative RT-PCR. The oncogenic phenotypes of GNG4 were determined with knockdown, knockout and forced expression experiments. We established and compared subcutaneous and liver metastatic mouse xenograft models of gastric cancer to reveal the roles of GNG4 in tumorigenesis in the liver.

RESULTS

GNG4 was upregulated substantially in primary gastric cancer tissues as well as liver metastatic lesions. High levels of GNG4 in primary cancer tissues were associated with short overall survival and the likelihood of liver recurrence. Functional assays revealed that GNG4 promoted cancer cell proliferation, the cell cycle and adhesiveness. Tumour formation by GNG4-knockout cells was moderately reduced in the subcutaneous mouse model and strikingly attenuated in the liver metastasis mouse model.

CONCLUSIONS

GNG4 expression may provide better disease monitoring for liver metastasis, and GNG4 may be a novel candidate therapeutic target for liver metastasis.

Therapeutic Approaches for Metastases from Colorectal Cancer and Pancreatic Ductal Carcinoma

Metastasis is the process of dissemination of a tumor, whereby cells from the primary site dislodge and find their way to other tissues where secondary tumors establish. Metastasis is the primary cause of death related to cancer. This process warrants changes in original tumoral cells and their microenvironment to establish a metastatic niche. Traditionally, cancer therapy has focused on metastasis prevention by systematic treatments or direct surgical re-sectioning. However, metastasis can still occur. More recently, new therapies direct their attention to targeting cancer stem cells. As they propose, these cells could be the orchestrators of the metastatic niche. In this review, we describe conventional and novel developments in cancer therapeutics for liver and lung metastasis. We further discuss the resistance mechanisms of targeted therapy, the advantages, and disadvantages of diverse treatment approaches, and future novel strategies to enhance cancer prognosis.

Toll-like receptors: exploring their potential connection with post-operative infectious complications and cancer recurrence

Cancer is the leading cause of death in North America. Despite modern advances in cancer therapy, many patients will ultimately develop cancer metastasis resulting in mortality. Surgery to resect early stage solid malignancies remains the cornerstone of cancer treatment. However, surgery places patients at risk of developing post-operative infectious complications that are linked to earlier cancer metastatic recurrence and cancer mortality. Toll-like receptors (TLRs) are evolutionarily-conserved sentinel receptors of the innate immune system that are activated by microbial products present during infection, leading to activation of innate immunity. Numerous types of solid cancer cells also express TLRs, with their activation augmenting their ability to metastasize. Similarly, healthy host-tissue TLRs activated during infection induce a prometastatic environment in the host. Cancer cells additionally secrete TLR activating ligands that activate both cancer TLRs and host TLRs to promote metastasis. Consequently, TLRs are an attractive therapeutic candidate to target infection-induced cancer metastasis and progression.

Roles of circRNAs in the tumour microenvironment

The tumour microenvironment (TME) constitutes the area surrounding the tumour during its development and has been demonstrated to play roles in cancer-related diseases through crosstalk with tumour cells. Circular RNAs (circRNAs) are a subpopulation of endogenous noncoding RNAs (ncRNAs) that are ubiquitously expressed in eukaryotes and have multiple biological functions in the regulation of cancer onset and progression. An increasing number of studies have shown that circRNAs participate in the multifaceted biological regulation of the TME. However, details on the mechanisms involved have remained elusive until now. In this review, we analyse the effects of circRNAs on the TME from various perspectives, including immune surveillance, angiogenesis, hypoxia, matrix remodelling, exo-circRNAs and chemoradiation resistance. Currently, the enormous potential for circRNA use in targeted therapy and as noninvasive biomarkers have drawn our attention. We emphasize the prospect of targeting circRNAs as an essential strategy to regulate TME, overcome cancer resistance and improve therapeutic outcomes.

CD4+ CD25+ regulatory T cells promote hepatocellular carcinoma invasion via TGF-β1-induced epithelial-mesenchymal transition

Background

CD4⁺ CD25⁺ regulatory T cells (Tregs), a crucial component of the infiltration of immune cells in tumor microenvironment, are associated with progression and metastasis of hepatocellular carcinoma (HCC).

Methods

The mechanism of Tregs in the invasion and metastasis of HCC was investigated in vivo and in vitro using immunohistochemical analysis, western blot, and quantitative reverse transcription-PCR (qRT-PCR).

Results

Analysis of 78 clinical HCC samples indicated that high expression of Tregs was strongly associated with poor cancer-free survival and overall survival of patients. The reduced expression of E-cadherin and enhanced expression of Vimentin and transforming growth factor-beta 1 (TGF-β1) were found in HCC tissue compared with normal liver tissue. The HCC Hepa1-6 cells were treated with the supernatant of Tregs-conditioned medium (Tregs-CM) to investigate the epithelial-mesenchymal transition (EMT) and TGF-β1. Western blot and qRT-PCR also showed that down-regulated E-cadherin and up-regulated Vimentin and TGF-β1 were found in Tregs-CM-treated Hepa1-6 cells. An experiment of tumorigenicity in C57 mice showed larger and heavier tumors in Tregs-CM-treated group than in the control group. Tregs produced higher TGF-β1 compared with Tregs treated with FOXP3 shRNA. TGF-β1 with neutralizing antibodies was used to deplete TGF-β1 in Tregs-CM, which enhanced expression of E-cadherin, reduced expression of Vimentin and TGF-β1, and decreased migratory and invasive capacity of Hepa1-6 cells.

Conclusion

Tregs could promote the invasion and migration of Hepa1-6 cells, which are possibly maintained by TGF-β1-induced EMT. This study showed that the development of therapeutic strategies against TGF-β1 pathway is valuable in HCC therapy.

PAI-1 secreted from metastatic ovarian cancer cells triggers the tumor-promoting role of the mesothelium in a feedback loop to accelerate peritoneal dissemination

The mesothelium, covered by a continuous monolayer of mesothelial cells, is the first protective barrier against metastatic ovarian cancer. However, mesothelial cells release tumor-promoting factors that accelerate the process of peritoneal metastasis. We identified cancer-associated mesothelial cells (CAMs) that had tumor-promoting potential. Here, we found that plasminogen activator inhibitor-1 (PAI-1) induced the formation of CAMs, after which CAMs increasingly secreted the oncogenic factors interleukin-8 (IL-8) and C-X-C motif chemokine ligand 5 (CXCL5), further promoting the metastasis of ovarian cancer cells in a feedback loop. After the formation of CAMs, PAI-1 activated the nuclear factor kappa B (NFκB) pathway in the CAMs, thus transcriptionally upregulating the expression of the downstream NFκB targets IL-8 and CXCL5. Moreover, PAI-1 correlated with peritoneal metastasis in ovarian cancer patients and indicated a poor prognosis. In both ex vivo and in vivo models, after PAI-1 expression was knocked down, the metastasis of ovarian cancer cells decreased significantly. Therefore, targeting PAI-1 may provide a potential target for future therapeutics to prevent the formation of CAMs and alleviate peritoneal metastasis in ovarian cancer patients.

Metabolomics uncovers a link between inositol metabolism and osteosarcoma metastasis

Cancer development and progression are characterized by complex molecular events. The acquisition of these events is primarily believed to result from alterations in gene and protein expression/function. Recent studies have also suggested the role of metabolic alterations, or "metabolic reprogramming," that may similarly contribute to these events. Indeed, our previous investigations in osteosarcoma (OS) identified metabolic changes uniquely linked to metastasis. Based on those findings, here we sought to build a more detailed understanding of the specific alterations in metabolites or metabolic pathways that may be responsible for the observed metastasis-associated metabolic alterations, suggested by gene expression data. This was pursued using a combination of high-throughput liquid- and gas-chromatography-based mass spectrometry (LC/MS and GC/MS) for a global metabolic profiling/subtraction of four pairs of high/low metastatic OS cell lines. By comparing the identity and level of the metabolites between high/low metastatic cells, several metabolic pathways were identified to be differentially activated, such as arginine, glutathione, inositol and fatty acid metabolic pathways. To further interrogate these results, we investigated the effects of inositol pathway dysregulation, through the exposure of metastatic OS cells to IP6 (inositol hexaphosphate). Although IP6 exposures had modest to minimal effects on cell proliferation, we observed reduced cellular glycolysis, down-regulation of PI3K/Akt signaling and suppression of OS metastatic progression. Collectively these data supported further investigation of metabolic sensitivities as anti-metastatic strategies in a clinical setting as well as investigation of altered metabolomics associated with metastatic progression.

Concordance of anaplastic lymphoma kinase (ALK) gene rearrangements between circulating tumor cells and tumor in non-small cell lung cancer

Anaplastic lymphoma kinase (ALK) gene rearrangement in non-small cell lung cancer (NSCLC) is routinely evaluated by fluorescent in-situ hybridization (FISH) testing on biopsy tissues. Testing can be challenging however, when suitable tissue samples are unavailable. We examined the relevance of circulating tumor cells (CTC) as a surrogate for biopsy-based FISH testing. We assessed paired tumor and CTC samples from patients with ALK rearranged lung cancer (n = 14), ALK-negative lung cancer (n = 12), and healthy controls (n = 5) to derive discriminant CTC counts, and to compare ALK rearrangement patterns. Blood samples were enriched for CTCs to be used for ALK FISH testing. ALK-positive CTCs counts were higher in ALK-positive NSCLC patients (3–15 cells/1.88 mL of blood) compared with ALK-negative NSCLC patients and healthy donors (0–2 cells/1.88 mL of blood). The latter range was validated as the ‘false positive’ cutoff for ALK FISH testing of CTCs. ALK FISH signal patterns observed on tumor biopsies were recapitulated in CTCs in all cases. Sequential CTC counts in an index case of lung cancer with no evaluable tumor tissue treated with crizotinib showed six, three and eleven ALK-positive CTCs per 1.88 mL blood at baseline, partial response and post-progression time points, respectively. Furthermore, ALK FISH rearrangement suggestive of gene copy number increase was observed in CTCs following progression. Recapitulation of ALK rearrangement patterns in the tumor on CTCs, suggested that CTCs might be used to complement tissue-based ALK testing in NSCLC to guide ALK-targeted therapy when suitable tissue biopsy samples are unavailable for testing.

Effect of Endostatin on Preventing Postoperative Progression of Distant Metastasis in a Murine Lung Cancer Model

Aims and Background

The relapse and metastasis of cancer remain a predominant cause of death after surgical removal of the primary tumor. There is a positive linkage between the postoperative upregulation of systemic angiogenic activity and distant tumor metastasis. In the present study, we established a spontaneous metastasis model and investigated whether antiangiogenic therapy using endostatin could prevent the progression of distant metastasis after removal of the primary tumor.

Methods

Female C57BL/6 mice were implanted subcutaneously with 1 × 106 Lewis lung cancer cells. Twenty days after implantation of the cancer cells, the primary tumor was removed and the mice were randomly divided into three groups. The NS group received normal saline, the L-ES group received 3 mg/kg endostatin, and the H-ES group received 20 mg/kg endostatin intravenously daily for 10 days. The effect of endostatin on lung metastases and the survival time of the mice were observed. Flow cytometry and immunohistochemistry were carried out to assess the angiogenic activity. The serum endostatin levels in peripheral blood were measured using an enzyme-linked immunosorbent assay.

Results

The mean number of metastatic pulmonary nodules and the mean net lung weight in the NS, L-ES and H-ES groups was 10.2, 2.8 and 4.0, and 0.55g, 0.31g and 0.36g, respectively. The difference between the NS group and the endostatin-treated groups was statistically significant (P <0.05). The endostatin-treated mice showed prolonged overall survival (P <0.05). Compared with the NS group, the endostatin-treated groups had lower levels of circulating endothelial cells in peripheral blood and showed a decrease in microvessel density in the metastatic tumors, with a more marked reduction in the L-ES group (P <0.05). The systemic presence of endostatin was gradually increased with the continued administration of endostatin to the mice.

Conclusions

Antiangiogenic therapy with endostatin is effective in inhibiting the postoperative progression of distant metastasis.

Efficacy in Treating Lung Metastasis of Invasive Breast Cancer with Functional Vincristine Plus Dasatinib Liposomes

Background: The metastasis of breast cancer is the leading cause of death, while lung metastasis is a major clinical phenomenon in patients with invasive breast cancer. The current treatment option comprising surgery, radiation, and standard chemotherapy cannot achieve a satisfactory effect on the treatment of lung metastasis of breast cancer. In this study, we report the potential of preventing lung metastasis of invasive breast cancer using the newly developed functional vincristine plus dasatinib liposomes. Methods: The investigations were performed on invasive breast cancer MDA-MB-231 cells in vitro and in lung metastatic model of invasive breast cancer MDA-MB-231 cells in nude mice. Results: The functional drug liposomes were able to induce cell cycle arrest at G2/M phase, induce apoptosis, inhibit adhesion, migration, and invasion of breast cancer cells in vitro, and prevent lung metastasis of breast cancer in nude mice. Conclusion: These findings indicate a potential clinical use of functional vincristine plus dasatinib liposomes for treating metastatic breast cancer.

Anti-tumor activity of nanomicelles encapsulating CXCR4 peptide antagonist E5

Cancer is the leading cause of death worldwide, and metastasis is the main attribute to cancer death. CXCR4 and its natural ligand CXCL12 have been known to play a critical role in tumorigenesis, angiogenesis and metastasis. Therefore, designing a new CXCR4 antagonist to prevent tumor metastasis will be of great significance. Herein, a novel chemically synthesized peptide (E5) that has an ability to target CXCR4/CXCL12 axis was loaded in micelle glycol-phosphatidylethanolamine (PEG-PE) block copolymer to form micelle-encapsulated E5 (M-E5). We demonstrated that M-E5 exhibited higher affinity for CXCR4-overexpressing MCF-7 and HepG2 tumor cells as compared to free E5, and efficiently inhibited the tumor cells migration. Mechanistic studies implied that PEG-PE micelle can encapsulate E5 and improve E5 targeting efficiency for CXCR4 by accumulating E5 on the tumor cell membrane. Furthermore, through encapsulation of chemotherapeutic drug doxorubicin (Dox) in PEG-PE micelle, we proved that PEG-PE micelle could serve as a co-carrier for both E5 and Dox (M-E5-Dox). M-E5 enhanced the efficiency of Dox by down-regulating the phosphorylation level of Akt, Erk and p38/MAPK proteins. In conclusion, PEG-PE micelle demonstrated a promising delivery system for E5, and M-E5 is expected to be a potential therapeutic agent that will help to improve the clinical benefits in current therapies used for solid tumors.

Upregulation of Glucose-Regulated Protein 78 in Metastatic Cancer Cells Is Necessary for Lung Metastasis Progression

Metastasis is the cause of more than 90% of all cancer deaths. Despite this fact, most anticancer therapeutics currently in clinical use have limited efficacy in treating established metastases. Here, we identify the endoplasmic reticulum chaperone protein, glucose-regulated protein 78 (GRP78), as a metastatic dependency in several highly metastatic cancer cell models. We find that GRP78 is consistently upregulated when highly metastatic cancer cells colonize the lung microenvironment and that mitigation of GRP78 upregulation via short hairpin RNA or treatment with the small molecule IT-139, which is currently under clinical investigation for the treatment of primary tumors, inhibits metastatic growth in the lung microenvironment. Inhibition of GRP78 upregulation and an associated reduction in metastatic potential have been shown in four highly metastatic cell line models: three human osteosarcomas and one murine mammary adenocarcinoma. Lastly, we show that downmodulation of GRP78 in highly metastatic cancer cells significantly increases median survival times in our in vivo animal model of experimental metastasis. Collectively, our data indicate that GRP78 is an attractive target for the development of antimetastatic therapies.

DDR2 Induces Gastric Cancer Cell Activities via Activating mTORC2 Signaling and Is Associated with Clinicopathological Characteristics of Gastric Cancer

BACKGROUND/AIM

Epithelial-mesenchymal transition (EMT) plays a role in cancer progression. Previous studies have suggested that discoidin domain receptor 2 (DDR2) is related to tumor progression and EMT. However, the role of DDR2 in regulating gastric cancer (GC) metastasis and in EMT has not been elucidated. In this study, we aimed to determine DDR2 expression and its clinical relation in GC and to investigate the effects of DDR2 on EMT and its underlying mechanisms.

METHODS

DDR2 expression and the relation to patients' clinicopathological features were assayed by Western blot or immunohistochemical staining. The effects of DDR2 overexpression were investigated using in vivo tumorigenicity and xenograft models. The effects of DDR2 on EMT marker expression were assayed by Western blot and immunofluorescence. The possible role of the mTORC pathway in these processes was explored.

RESULTS

DDR2 showed high expression in GC tissues and cells. DDR2 expression was negatively correlated with E-cadherin expression and positively correlated with N-cadherin and vimentin expression. High DDR2 expression is correlated with unfavorable pathoclinical features such as multiple tumor locations and intestinal-type GC. In xenograft models, DDR2 overexpression promoted tumor formation. Furthermore, DDR2 expression impacted on the invasion and motility of GC cells, accompanied by changes in EMT marker expression. Finally, our results revealed that DDR2 facilitates GC cell invasion and EMT through mTORC2 activation and AKT phosphorylation.

CONCLUSION

DDR2 is upregulated and correlated with unfavorable clinical features of GC patients. DDR2 promotes tumor formation and invasion through facilitating EMT process via mTORC2 activation and AKT phosphorylation.

The Growth Inhibitory Potential and Antimetastatic Effect of Camel Urine on Breast Cancer Cells In Vitro and In Vivo

Although it may sound unpleasant, camel urine has been consumed extensively for years in the Middle East as it is believed to be able to treat a wide range of diseases such as fever, cold, or even cancer. People usually take it by mixing small drops with camel milk or take it directly. The project aims to study the effects of camel urine in inhibiting the growth potential and metastatic ability of 4T1 cancer cell line in vitro and in vivo. Based on the MTT result, the cytotoxicity of camel urine against 4T1 cell was established, and it was dose-dependent. Additionally, the antimetastatic potential of camel urine was tested by running several assays such as scratch assay, migration and invasion assay, and mouse aortic ring assay with promising results in the ability of camel urine to inhibit metastatic process of the 4T1 cells. In order to fully establish camel urine's potential, an in vivo study was carried out by treating mice inoculated with 4T1 cells with 2 different doses of camel urine. By the end of the treatment period, the tumor in both treated groups had reduced in size as compared to the control group. Additional assays such as the TUNEL assay, immunophenotyping, cytokine level detection assay, clonogenic assay, and proteome profiler demonstrated the capability of camel urine to reduce and inhibit the metastatic potential of 4T1 cells in vivo. To sum up, further study of anticancer properties of camel urine is justified, as evidenced through the in vitro and in vivo studies carried out. Better results were obtained at higher concentration of camel urine used in vivo. Apart from that, this project has laid out the mechanisms employed by the substance to inhibit the growth and the metastatic process of the 4T1 cell.

Predilection of contralateral upper lung metastasis in upper lobe lung adenocarcinoma patients

BACKGROUND

Lung cancer with lung to lung metastasis is common. The objective of this study was to investigate the association among the distribution of contralateral lung metastases versus primary lung tumor location, clinical characteristics, and epidermal growth factor receptor (EGFR) mutations status.

METHODS

The study included treatment-naïve stage IV lung adenocarcinoma with contralateral lung metastases from 2012 through 2013.

RESULTS

In total, 103 patients were enrolled after excluding lung cancer with histology other than adenocarcinoma, synchronous multiple primary lung cancers, or other active malignancy. The median age was 65 years (range, 28-93 years); 47 male patients (45.6%); 69 non-smoker (NS) patients (67.0%); 68 Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1 patients (66.0%); 38 M1a patients (38.9%); and 60 EGFR mutation patients (58.3%). There were 51 cases (49.5%) with primary lung cancer located over upper lobes. Among them, 36 (70.6%) had contralateral upper lung predominance metastasis, 9 (17.6%) had lower lung predominance, and 6 (11.8%) had equal distribution. Among the 52 lower lobe tumors, 17 (32.7%), 19 (36.5%), and 16 (30.8%) had upper, lower lung predominance, and equal distribution metastasis, respectively. Univariate analysis showed only male gender and primary tumor location over upper lobes were significantly associated with contralateral upper lung predominance metastases. After multivariate analysis, only primary tumor location over upper lobes was significantly associated with contralateral upper lung predominance metastases (adjusted OR 5.49, 95% CI, 2.15-14.03, P<0.001).

CONCLUSIONS

Upper lobe lung adenocarcinoma was significantly associated with contralateral upper lung predominance metastases. Further research is needed to elucidate the mechanisms underlying this phenomenon.

Novel effects of FTY720 on perinuclear reorganization of keratin network induced by sphingosylphosphorylcholine: Involvement of protein phosphatase 2A and G-protein-coupled receptor-12

Sphingosylphosphorylcholine (SPC) evokes perinuclear reorganization of keratin 8 (K8) filaments and regulates the viscoelasticity of metastatic cancer cells leading to enhanced migration. Few studies have addressed the compounds modulating the viscoelasticity of metastatic cancer cells. We studied the effects of sphingosine (SPH), sphingosine 1-phosphate (S1P), FTY720 and FTY720-phosphate (FTY720P) on SPC-induced K8 phosphorylation and reorganization using Western blot and confocal microscopy, and also evaluated the elasticity of PANC-1 cells by atomic force microscopy. FTY720, FTY720P, SPH, and S1P concentration-dependently inhibited SPC-evoked phosphorylation and reorganization of K8, and migration of PANC-1 cells. SPC triggered reduction and narrow distribution of elastic constant K and conversely, FTY720 blocked them. A common upstream regulator of JNK and ERK, protein phosphatase 2A (PP2A) expression was reduced by SPC, but was restored by FTY720 and FTY72P. Butyryl forskolin, a PP2A activator, suppressed SPC-induced K8 phosphorylation and okadaic acid, a PP2A inhibitor, induced K8 phosphorylation. Gene silencing of PP2A also led to K8 phosphorylation, reorganization and migration. We also investigated the involvement of GPR12, a high-affinity SPC receptor, in SPC-evoked keratin phosphorylation and reorganization. GPR12 siRNA suppressed the SPC-triggered phosphorylation and reorganization of K8. GPR12 overexpression stimulated keratin phosphorylation and reorganization even without SPC. FTY720 and FTY720P suppressed the GPR12-induced phosphorylation and reorganization of K8. The collective data indicates that FTY720 and FTY720P suppress SPC-induced phosphorylation and reorganization of K8 in PANC-1 cells by restoring the expression of PP2A via GPR12. These findings might be helpful in the development of compounds that modulate the viscoelasticity of metastatic cancer cells and various SPC actions.

Extracellular vesicle-mediated transfer of processed and functional RNY5 RNA

Extracellular vesicles (EVs) have been proposed as a means to promote intercellular communication. We show that when human primary cells are exposed to cancer cell EVs, rapid cell death of the primary cells is observed, while cancer cells treated with primary or cancer cell EVs do not display this response. The active agents that trigger cell death are 29- to 31-nucleotide (nt) or 22- to 23-nt processed fragments of an 83-nt primary transcript of the human RNY5 gene that are highly likely to be formed within the EVs. Primary cells treated with either cancer cell EVs, deproteinized total RNA from either primary or cancer cell EVs, or synthetic versions of 31- and 23-nt fragments trigger rapid cell death in a dose-dependent manner. The transfer of processed RNY5 fragments through EVs may reflect a novel strategy used by cancer cells toward the establishment of a favorable microenvironment for their proliferation and invasion.

The Mesothelial Origin of Carcinoma Associated-Fibroblasts in Peritoneal Metastasis

Solid tumors are complex and unstructured organs that, in addition to cancer cells, also contain other cell types. Carcinoma-associated fibroblasts (CAFs) represent an important population in the tumor microenviroment and participate in several stages of tumor progression, including cancer cell migration/invasion and metastasis. During peritoneal metastasis, cancer cells detach from the primary tumor, such as ovarian or gastrointestinal, disseminate through the peritoneal fluid and colonize the peritoneum. Tumor cells metastasize by attaching to and invading through the mesothelial cell (MC) monolayer that lines the peritoneal cavity, then colonizing the submesothelial compact zone where CAFs accumulate. CAFs may derive from different sources depending on the surrounding metastatic niche. In peritoneal metastasis, a sizeable subpopulation of CAFs originates from MCs through a mesothelial-to-mesenchymal transition (MMT), which promotes adhesion, invasion, vascularization and subsequent tumor growth. The bidirectional communication between cancer cells and MC-derived CAFs via secretion of a wide range of cytokines, growth factors and extracellular matrix components seems to be crucial for the establishment and progression of the metastasis in the peritoneum. This manuscript provides a comprehensive review of novel advances in understanding how peritoneal CAFs provide cancer cells with a supportive microenvironment, as well as the development of future therapeutic approaches by interfering with the MMT in the peritoneum.

Netrin-1 as a potential target for metastatic cancer: focus on colorectal cancer

Despite advanced screening technology and cancer treatments available today, metastasis remains an ongoing major cause of cancer-related deaths worldwide. Typically, colorectal cancer is one of the cancers treatable by surgery in conjunction with chemotherapy when it is detected at an early stage. However, it still ranks as the second highest modality and mortality of cancer types in western countries, and this is mostly due to a recurrence of metastatic colorectal cancer post-resection of the primary malignancy. Colorectal cancer metastases predominantly occur in the liver and lung, and yet the molecular mechanisms that regulate these organ-specific colorectal cancer metastases are largely unknown. Therefore, the identification of any critical molecule, which triggers malignancy in colorectal cancer, would be an excellent target for treatment. Netrin-1 was initially discovered as a chemotropic neuronal guidance molecule, and has been marked as a regulator for many cancers including colorectal cancer. Here, we summarise key findings of the role of netrin-1 intrinsic to colorectal cancer cells, extrinsic to the tumour microenvironment and angiogenesis, and consequently, we evaluate netrin-1 as a potential target molecule for metastasis.

Intravitreally Injected HCmel12 Melanoma Cells Serve as a Mouse Model of Tumor Biology of Intraocular Melanoma

PURPOSE

To establish a mouse model with histologic characteristics of uveal melanoma for investigation of intraocular tumor biology of melanoma.

METHODS

After injection of 1 × 10(5) of HCmel12 melanoma cells, a cutaneous melanoma cell line, into the vitreous of CX3CR1(+/GFP) or C57Bl/6 mice (n = 12), tumor growth patterns, clinicopathological features, angiogenesis and metastatic behavior were analyzed by histology (hematoxylin and eosin, periodic acid-Schiff without hematoxylin) and immunohistochemistry (HMB45/MART-1-Ab, F4/80-Ab, green fluorescent protein (GFP)-Ab and VE-cadherin-Ab).

RESULTS

HCmel12 cells formed intraocularly growing tumor masses, which showed histologic features of intraocular melanoma such as angiotropism, intratumoral endothelial-lined vasculature, vasculogenic mimicry including prognostic significant extravascular matrix patterns, and invasion by inflammatory cells, in particular macrophages. There was no difference in tumor growth characteristics between CX3CR1(+/GFP) and C57Bl/6 mice. Five of 10 mice proceeded to extrascleral tumor growth and three of these developed metastases.

CONCLUSIONS

Intraocularly injected HCmel12 cells developed tumor masses with histologic characteristics of aggressive melanoma similar to human uveal melanoma. Since hematogenous dissemination to the liver was not observed, intravitreally injected HCmel12 cells do not qualify as a model for metastasizing intraocular melanoma. However, since the eye represents a semi-closed compartment with access to constant blood supply, these intraocular tumors represent a model for studies of isolated parameters in general tumor biology of intraocular melanoma.

Novel Suppressive Effects of Ketotifen on Migration and Invasion of MDA-MB-231 and HT-1080 Cancer Cells

The high mortality rates associated with cancer reflect the metastatic spread of tumor cells from the site of their origin. Metastasis, in fact, is the cause of 90% of cancer deaths. Therefore, considerable effort is being made to inhibit metastasis. In the present study, we screened ketotifen for anti-migratory and anti-invasive activities against MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer cells. Cancer cell migration and invasion were measured using multi-well chambers. Additionally, western blots were used to examine the effects of ketotifen on the expressions of CDC42, Rho, Rac, and matrix metalloproteinase 9 (MMP-9). The results showed that ketotifen dose-dependently suppressed the migration and invasion of MDA-MB-231 and HT-1080 cells. Ketotifen also suppressed the expressions of CDC42, Rac, and Rho, which, significantly, are involved in MDA-MB-231 and HT-1080 cancer cell migration. Moreover, ketotifen suppressed the expression and activity of MMP-9, which is involved in degradation of the extracellular matrix leading to invasion. The overall data suggested that ketotifen suppresses the migration and invasion of MDA-MB-231 and HT-1080 cancer cells via inhibition of CDC42, Rac, Rho, and MMP-9 expression.

Array-based proteomic approaches to study signal transduction pathways: prospects, merits and challenges

Very often dysfunctional aspects of various signalling networks are found to be associated with human diseases and disorders. The major characteristics of signal transduction pathways are specificity, amplification of the signal, desensitisation and integration, which is accomplished not solely, but majorly by proteins. Array-based profiling of protein-protein and other biomolecular interactions is a versatile approach, which holds immense potential for multiplex interactome mapping and provides an inclusive representation of the signal transduction pathways and networks. Protein microarrays such as analytical protein microarrays (antigen-antibody interactions, autoantibody screening), RP microarrays (interaction of a particular ligand with all the possible targets in cell), functional protein microarrays (protein-protein or protein-ligand interactions) are implemented for various applications, including analysis of protein interactions and their significance in signalling cascades. Additionally, successful amalgamation of the array-based approaches with different label-free detection techniques allows real-time analysis of interaction kinetics of multiple interaction events simultaneously. This review discusses the prospects, merits and limitations of different variants of array-based techniques and their promising applications for studying the modifications and interactions of biomolecules, and highlights the studies associated with signal transduction pathways and their impact on disease pathobiology.

Tumour-stroma crosstalk in the development of squamous cell carcinoma

Squamous cell carcinoma (SCC) represents one of the most frequently diagnosed tumours and contributes significant mortality worldwide. Recent deep sequencing of cancer genomes has identified common mutations in SCC arising across different tissues highlighting perturbation of squamous differentiation as a key event. At the same time significant data have been accumulating to show that common tumour-stroma interactions capable of driving disease progression are also evident when comparing SCC arising in different tissues. We and others have shown altered matrix composition surrounding SCC can promote tumour development. This review focuses on some of the emerging data with particular emphasis on SCC of head and neck and skin with discussion on the potential tumour suppressive properties of a normal microenvironment. Such data indicate that regardless of the extent and type of somatic mutation it is in fact the tumour context that defines metastatic progression.

Toward a drug development path that targets metastatic progression in osteosarcoma

Despite successful primary tumor treatment, the development of pulmonary metastasis continues to be the most common cause of mortality in patients with osteosarcoma. A conventional drug development path requiring drugs to induce regression of established lesions has not led to improvements for patients with osteosarcoma in more than 30 years. On the basis of our growing understanding of metastasis biology, it is now reasonable and essential that we focus on developing therapeutics that target metastatic progression. To advance this agenda, a meeting of key opinion leaders and experts in the metastasis and osteosarcoma communities was convened in Bethesda, Maryland. The goal of this meeting was to provide a "Perspective" that would establish a preclinical translational path that could support the early evaluation of potential therapeutic agents that uniquely target the metastatic phenotype. Although focused on osteosarcoma, the need for this perspective is shared among many cancer types. The consensus achieved from the meeting included the following: the biology of metastatic progression is associated with metastasis-specific targets/processes that may not influence grossly detectable lesions; targeting of metastasis-specific processes is feasible; rigorous preclinical data are needed to support translation of metastasis-specific agents into human trials where regression of measurable disease is not an expected outcome; preclinical data should include an understanding of mechanism of action, validation of pharmacodynamic markers of effective exposure and response, the use of several murine models of effectiveness, and where feasible the inclusion of the dog with naturally occurring osteosarcoma to define the activity of new drugs in the micrometastatic disease setting.

Spheroid formation and invasion capacity are differentially influenced by co-cultures of fibroblast and macrophage cells in breast cancer

Interactions with stromal components influence the growth, survival, spread, and colonization capacities of tumor cells. Fibroblasts and macrophages which are responsible for the stroma production and maintenance are of the basic elements found in tumor microenvironment. Cellular density and ratio of stromal cells to tumor cells can also have modulatory effects in cancer. Here, the contribution of fibroblast and/or macrophage cells on the malignant behavior of breast cancer cells was modeled in co-culture systems. Co-cultures were established at different cell densities and ratios with 4T1 breast cancer, NIH/3T3 or 3T3-L1 fibroblast, and J774A.1 monocyte/macrophage cell lines. Flow cytometry-based proliferation, 3D growth on alginate matrix, and matrigel invasion assays were performed to determine the change in the malignant assets of tumor cells. The data were also supported by immunocytochemical and morphological analyses. Co-culturing with fibroblasts (especially, NIH/3T3 cells) significantly supported the proliferation, scattering, and invasiveness of 4T1 cells whereas inclusion of macrophages disrupted this positive influence. On the other hand, the invasion capacity of 4T1 cells was not enhanced in the co-cultures with fibroblasts whose motility were inhibited with pertussis toxin pretreatment. Particularly at low-density seeding in 3D cultures, 4T1 cells could form substantially more spheroids than that of in the co-cultures with fibroblasts. Only, increasing the amount of fibroblasts could restore the 3D-growth. Intriguingly, co-existence of macrophage, fibroblast, and tumor cells in 3D cultures provided a convenient stroma sustaining the spheroid formation and growth. In conclusion, fibroblasts can form a favorable environment for tumor cells' spread and motility whereas restricting their 3D-growth capacity. On the other hand, presence of macrophages may disrupt the influence of fibroblasts and enhance the spheroid formation by the tumor cells.

Role of ezrin in osteosarcoma metastasis

The cause of death for the vast majority of cancer patients is the development of metastases at sites distant from that of the primary tumor. For most pediatric sarcoma patients such as those with osteosarcoma (OS), despite successful management of the primary tumor through multimodality approaches, the development of metastases, commonly to the lungs, is the cause of death. Significant improvements in long-term outcome for these patients have not been seen in more than 30 years. Furthermore, the long-term outcome for patients who present with metastatic disease is grave [1-5]. New treatment options are needed.Opportunities to improve outcomes for patients who present with metastases and those at-risk for progression and metastasis require an improved understanding of cancer progression and metastasis. With this goal in mind we and others have identified ezrin as a metastasis-associated protein that associated with OS and other cancers. Ezrin is the prototypical ERM (Ezrin/Radixin/Moesin) protein family member. ERMs function as linker proteins connecting the actin cytoskeleton and the plasma membrane. Since our initial identification of ezrin in pediatric sarcoma, an increasing understanding the role of ezrin in metastasis has emerged. Briefly, ezrin appears to allow metastatic cells to overcome a number of stresses experienced during the metastatic cascade, most notably the stress experienced as cells interact with the microenvironment of the secondary site. Cells must rapidly adapt to this environment in order to survive. Evidence now suggests a connection between ezrin expression and a variety of mechanisms linked to this important cellular adaptation including the ability of metastatic cells to initiate the translation of new proteins and to allow the efficient generation of ATP through a variety of sources. This understanding of the role of ezrin in the biology of metastasis is now sufficient to consider ezrin as an important therapeutic target in osteosarcoma patients. This chapter reviews our understanding of ezrin and the related ERM proteins in normal tissues and physiology, summarizes the expression of ezrin in human cancers and associations with clinical parameters of disease progression, reviews reports that detail a biological understanding of ezrin's role in metastatic progression, and concludes with a rationale that may be considered to target ezrin and ezrin biology in osteosarcoma.

Silencing of CXCR4 inhibits tumor cell proliferation and neural invasion in human hilar cholangiocarcinoma

Background/Aims

To evaluate the expression of CXC motif chemokine receptor 4 (CXCR4) in the tissues of patients with hilar cholangiocarcinoma (hilar-CCA) and to investigate the cell proliferation and frequency of neural invasion (NI) influenced by RNAi-mediated CXCR4 silencing.

Methods

An immunohistochemical technique was used to detect the expression of CXCR4 in 41 clinical tissues, including hilar-CCA, cholangitis, and normal bile duct tissues. The effects of small interference RNA (siRNA)-mediated CXCR4 silencing were detected in the hilar-CCA cell line QBC939. Cell proliferation was determined by MTT. Expression of CXCR4 was monitored by quantitative real time polymerase chain reaction and Western blot analysis. The NI ability of hilar-CCA cells was evaluated using a perineural cell and hilar-CCA cell coculture migration assay.

Results

The expression of CXCR4 was significantly induced in clinical hilar-CCA tissue. There was a positive correlation between the expression of CXCR4 and lymph node metastasis/NI in hilar-CCA patients (p<0.05). Silencing of CXCR4 in tumor cell lines by siRNA led to significantly decreased NI (p<0.05) and slightly decreased cell proliferation.

Conclusions

CXCR4 is likely correlated with clinical recurrence of hilar-CCA. CXCR4 is involved in the invasion and proliferation of human hilar-CCA cell line QBC939, indicating that CXCR4 could be a promising therapeutic target for hilar-CCA.

Identification of stromal differentially expressed proteins in the colon carcinoma by quantitative proteomics

Tumor microenvironment plays very important roles in the carcinogenesis. A variety of stromal cells in the microenvironment have been modified to support the unique needs of the malignant state. This study was to discover stromal differentially expressed proteins (DEPs) that were involved in colon carcinoma carcinogenesis. Laser capture microdissection (LCM) was captured and isolated the stromal cells from colon adenocarcinoma (CAC) and non-neoplastic colon mucosa (NNCM) tissues, respectively. Seventy DEPs were identified between the pooled LCM-enriched CAC and NNCM stroma samples by iTRAQ-based quantitative proteomics. Gene Ontology (GO) relationship analysis revealed that DEPs were hierarchically grouped into 10 clusters, and were involved in multiple biological functions that were altered during carcinogenesis, including extracellular matrix organization, cytoskeleton, transport, metabolism, inflammatory response, protein polymerization, and cell motility. Pathway network analysis revealed 6 networks and 56 network eligible proteins with Ingenuity pathway analysis. Four significant networks functioned in digestive system development and its function, inflammatory disease, and developmental disorder. Eight DEPs (DCN, FN1, PKM2, HSP90B1, S100A9, MYH9, TUBB, and YWHAZ) were validated by Western blotting, and four DEPs (DCN, FN1, PKM2, and HSP90B1) were validated by immunohistochemical analysis. It is the first report of stromal DEPs between CAC and NNCM tissues. It will be helpful to recognize the roles of stromas in the colon carcinoma microenvironment, and improve the understanding of carcinogenesis in colon carcinoma. The present data suggest that DCN, FN1, PKM2, HSP90B1, S100A9, MYH9, TUBB, and YWHAZ might be the potential targets for colon cancer prevention and therapy.

Resolvin D1 inhibits TGF-β1-induced epithelial mesenchymal transition of A549 lung cancer cells via lipoxin A4 receptor/formyl peptide receptor 2 and GPR32

Epithelial-mesenchymal-transition (EMT) is a key event for tumor cells to initiate metastasis which lead to switching of E-cadherin to N-cadherin. Resolvins are known to promote the resolution of inflammation and phagocytosis of macrophages. However, the role of resolvins in EMT of cancer is not known. Therefore, we examined the effects of resolvins on transforming growth factor, beta 1 (TGF-β1)-induced EMT. Expression of E-cadherin and N-cadherin in A549 lung cancer cells was evaluated by Western blot and confocal microscopy. Involvement of lipoxin A4 receptor/formyl peptide receptor 2 (ALX/FPR2) was examined by gene silencing. TGF-β1 induced expression of N-cadherin in A549 lung cancer cells, and resolvin D1 and D2 inhibited the expression of N-cadherin at low concentrations (1-100 nM). Resolvin D1 and D2 also suppressed the expression of zinc finger E-box binding homeobox 1 (ZEB1). The effects of resolvin D1 and D2 were confirmed in other lung cancer cell lines such as H838, H1299, and H1703. Resolvin D1 and D2 did not affect the proliferation of A549 lung cancer cells. Resolvin D1 and D2 also suppressed the TGF-β1-induced morphological change. Resolvin D1 and D2 also inhibited the TGF-β1-induced migration and invasion of A549 cells. Resolvin D1 is known to act via ALX/FPR2 and GPR32. Thus, we examined the involvement of ALX/FPR2 and GPR32 in the suppressive effects of resolvin D1 on TGF-β1-induced EMT of A549 cells. Gene silencing of ALX/FPR2 and GPR32 blocked the action of resolvin D1. Overexpression of ALX/FPR2 or GPR32 increased the effects of resolvin D1. These results suggest that resolvin D1 inhibited TGF-β1-induced EMT via ALX/FPR2 and GPR32 by reducing the expression of ZEB1.

Bone-stromal cells up-regulate tumourigenic markers in a tumour-stromal 3D model of prostate cancer

Background

The cellular and molecular mechanisms that mediate interactions between tumour cells and the surrounding bone stroma are to date largely undetermined in prostate cancer (PCa) progression. The purpose of this study was to evaluate the role of alpha 6 and beta 1 integrin subunits in mediating tumour-stromal interactions.

Methods

Utilising 3D in vitro assays we evaluated and compared 1. Monocultures of prostate metastatic PC3, bone stromal derived HS5 and prostate epithelial RWPE-1 cells and 2. Tumour-stromal co-cultures (PC3 + HS5) to ascertain changes in cellular phenotype, function and expression of metastatic markers.

Results

In comparison to 3D monocultures of PC3 or HS5 cells, when cultured together, these cells displayed up-regulated invasive and proliferative qualities, along with altered expression of epithelial-to-mesenchymal and chemokine protein constituents implicated in metastatic dissemination. When co-cultured, HS5 cells were found to re-express N-Cadherin and chemokine receptor CXCR7. Alterations in N-Cadherin expression were found to be mediated by soluble factors secreted by PC3 tumour cells, while chemokine receptor re-expression was dependent on direct cell-cell interactions. We have also shown that integrins beta 1 and alpha 6 play an integral role in maintaining cell homeostasis and mediating expression of E-Cadherin, N-Cadherin and vimentin, in addition to chemokine receptor CXCR7.

Conclusions

Collectively our results suggest that both PC3 and HS5 cells provide a “protective” and reciprocal milieu that promotes tumour growth. As such 3D co-cultures may serve as a more complex and valid biological model in the drug discovery pipeline.

The role of p53 protein and MMP-2 tumor/stromal cells expression on progressive growth of ovarian neoplasms

The aim of our study was to evaluate p53 gene/protein status and MMP-2 expression in respect to ovarian tumors progress to define the role of these markers in the metastasis of ovarian carcinomas. MMP-2 and p53 alterations were evaluated on 80 malignant, 30 benign ovarian tumors, and 62 metastatic lesions by using HRM method for mutations in p53 gene and by using RT-PCR for mRNA MMP-2 level. Our data indicate that parallel expression of MMP-2 epithelial/stromal cells and p53 may enhance cells invasion and metastasis in ovarian carcinoma.

Multiple skeletal muscle metastases from colon carcinoma preceded by paraneoplastic dermatomyositis

Skeletal muscle metastases are very rare events in colorectal carcinoma. By contrast, dermatomyositis is an idiopathic inflammatory myopathy with characteristic cutaneous manifestations and a well-recognized association with several human malignancies and, among others, colorectal cancer. Here, we report the case of a 71-year-old woman with paraneoplastic dermatomyositis followed by the development of a metastatic colon cancer. Interestingly, this patient developed multiple skeletal metastases which were preceded by the worsening of systemic symptoms of dermatomyositis. This observation suggests that, while muscle tissue is usually resistant to the development of tumor metastases, the inflammatory and immune response which characterizes and boosts paraneoplastic myopathy may represent a favorable soil for tumor cell invasion and metastasization to skeletal muscles.

Seed, soil, and beyond: The basic biology of brain metastasis

First invoked by Paget, the seed and soil hypothesis suggests that the successful growth of metastatic cells depends on the interactions and properties of cancer cells (seeds) and their potential target organs (soil). In the context of the seed and soil hypothesis this review examines recent advances in the understanding of molecular and cellular features that permit transformed epithelial cells to gain access to the blood stream (intravasation), survive their journey through the blood stream, and ultimately traverse through the microvasculature of target organs (extravsation) to deposit, survive, and grow in a foreign tissue environment. In addition to a review of the clinical and experimental evidence supporting the seed and soil theory to cancer metastasis, additional concepts highlighted include: (i) The role of cancer stem-like cells as putative cells of metastatic origin (the "seeds"); (ii) the mechanism of epithelial to mesenchymal transition (EMT) in driving epithelial cell conthose molecules do no blood stream to avoid anoikis, or anchorage independent cell death; and (iv) the reverse process of EMT, or mesenchymal to epithelial transition (MET), which promotes conversion back to the parent cell morphology and growth of macrometastsis in the target organ. The unique biology of metastases once established in the brain, and in particular the "sanctuary" role that the brain microenvironment plays in promoting metastatic growth and treatment resistance, will also be examined. These issues are of more than academic interest since as systemic therapies gradually improve local tumor control, the relative impact of brain metastasis will inexorably play a proportionally greater role in determining patient morbidity and mortality.

Controversies in the management of brain metastases

The multidisciplinary management of brain metastases has generated substantial controversy as treatment has diversified in recent years. Debate about the type, role, and timing of different diagnostic and therapeutic strategies has promoted rigorous scientific research into efficacy. However, much still remains unanswered in the treatment of this difficult disease process. This manuscript seeks to highlight some of the controversies identified in previous sections of this supplement, including prognosis, pathology, radiation and surgical treatment, neuroimaging, and the biochemical underpinnings of brain metastases. By recognizing what is yet unanswered, we hope to identify areas in which further research may yield promising results.

The role of tumour-stromal interactions in modifying drug response: challenges and opportunities

The role of stromal cells and the tumour microenvironment in general in modulating tumour sensitivity is increasingly becoming a key consideration for the development of active anticancer therapeutics. Here, we discuss how these tumour-stromal interactions affect tumour cell signalling, survival, proliferation and drug sensitivity. Particular emphasis is placed on the ability of stromal cells to confer - to tumour cells - resistance or sensitization to different classes of therapeutics, depending on the specific microenvironmental context. The mechanistic understanding of these microenvironmental interactions can influence the evaluation and selection of candidate agents for various cancers, in both the primary site as well as the metastatic setting. Progress in in vitro screening platforms as well as orthotopic and 'orthometastatic' xenograft mouse models has enabled comprehensive characterization of the impact of the tumour microenvironment on therapeutic efficacy. These recent advances can hopefully bridge the gap between preclinical studies and clinical trials of anticancer agents.

Existence of glioma stroma mesenchymal stemlike cells in Korean glioma specimens

PURPOSE

It was presented that mesenchymal stem cells (MSCs) can be isolated from western glioma specimens. However, whether MSCs exist in glioma specimens of different ethnicities is unknown. To verify the existence of MSCs in an independent cohort, we undertook studies to isolate MSCs from a group of Korean patients. We hypothesized that cells resembling MSCs that were deemed mesenchymal stemlike cells (MSLCs) exist in an independent cohort of Korean gliomas.

METHODS

We cultured fresh glioma specimens using the protocols used for culturing MSCs. The cultured cells were analyzed with fluorescence-activated cell sorting (FACS) for surface markers associated with MSCs. Cultured cells were exposed to mesenchymal differentiation conditions. To presume possible locations of MSLCs in the glioma, sections of glioma were analyzed by immunofluorescent labeling for CD105, CD31, and NG2.

RESULTS

From nine of 31 glioma specimens, we isolated cells resembling MSCs, which were deemed Korean glioma stroma MSLCs (KGS-MSLCs). KGS-MSLCs were spindle shaped and adherent to plastic. KGS-MSLCs had similar surface markers to MSCs (CD105(+), CD90(+), CD73(+), and CD45(-)). KGS-MSLCs were capable of mesenchymal differentiation and might be located around endothelial cells, pericytes, and in a disorganized perivascular area inside glioma stroma.

CONCLUSIONS

We found that cells resembling MSCs indeed exist in an independent cohort of glioma patients, as presented in western populations. We could presume that the possible location of KGS-MSLCs was in perivascular area or in glioma stroma that was a disorganized vascular niche. It might be possible that KGS-MSLCs could be one of constituent of stroma of glioma microenvironment.

Hypoxia induces epithelial-mesenchymal transition via activation of SNAI1 by hypoxia-inducible factor -1α in hepatocellular carcinoma

Background

High invasion and metastasis are the primary factors causing poor prognosis of patients with hepatocellular carcinoma (HCC). However, the molecular mechanisms underlying these biological behaviors have not been completely elucidated. In this study, we investigate the molecular mechanism by which hypoxia promotes HCC invasion and metastasis through inducing epithelial-mesenchymal transition (EMT).

Methods

The expression of EMT markers was analyzed by immunohistochemistry. Effect of hypoxia on induction of EMT and ability of cell migration and invasion were performed. Luciferase reporter system was used for evaluation of Snail regulation by hypoxia-inducible factor -1α (HIF-1α).

Results

We found that overexpression of HIF-1α was observed in HCC liver tissues and was related to poor prognosis of HCC patients. HIF-1α expression profile was correlated with the expression levels of SNAI1, E-cadherin, N-cadherin and Vimentin. Hypoxia was able to induce EMT and enhance ability of invasion and migration in HCC cells. The same phenomena were also observed in CoCl2-treated cells. The shRNA-mediated HIF-1α suppression abrogated CoCl2-induced EMT and reduced ability of migration and invasion in HCC cells. Luciferase assay showed that HIF-1α transcriptional regulated the expression of SNAI1 based on two hypoxia response elements (HREs) in SNAI1 promoter.

Conclusions

We demonstrated that hypoxia-stabilized HIF1α promoted EMT through increasing SNAI1 transcription in HCC cells. This data provided a potential therapeutic target for HCC treatment.

Expression of the homeostasis-related markers, maspin, heat shock proteins 70 & 90, glutathione S-transferase, aquaporin 5 and NF-kB in young and old labial and palatal salivary glands

Intraoral salivary glands undergo remarkable age-related morphologic changes. This study investigated the expression of a panel of molecular markers known for cellular homeostatic activity, dependent on age and location of the salivary glands. Samples taken from healthy subjects were classified according to age ("young" <45 years, n=51, and "old" ≥60 years, n=45) and location (lip, n=47 and palate, n=49). They were immunohistochemically stained for mammary serine protease inhibitor (maspin), heat shock protein (HSP)70, HSP90, glutathione S-transferase (GST), aquaporine5 (AQP5), and nuclear factor kappa-B (NF-κB) for assessment of their expression in acini and ducts, and in cytoplasmic and nuclear compartments. Results were expressed as the mean percentage of positively stained component per age group, gland location and type of cell and cellular compartment. Statistical analysis was performed by two-way ANOVA and crosstabs. The expression of maspin was lower in the old group in both the palatal and labial glands (acini and ducts, cytoplasm and nuclei) compared to the young group (p<0.05). In both age groups, when compared to labial glands, palatal glands exhibited higher expression of HSP70 (p<0.05) and lower expression of AQP5 (p<0.001) and NF-κB (p=0.018). Collectively, the low expression of factors capable of preserving cellular homeostasis (i.e., maspin and AQP5) vis-à-vis a high expression of factors that are also related to cell survival (i.e., HSPs) that was demonstrated in the old palatal glands may point to their high vulnerability to undergo selective phenotypic changes.

Integrated microRNA and mRNA signatures associated with survival in triple negative breast cancer

Triple negative breast cancer (TNBC) is a heterogeneous disease at the molecular, pathologic and clinical levels. To stratify TNBCs, we determined microRNA (miRNA) expression profiles, as well as expression profiles of a cancer-focused mRNA panel, in tumor, adjacent non-tumor (normal) and lymph node metastatic lesion (mets) tissues, from 173 women with TNBCs; we linked specific miRNA signatures to patient survival and used miRNA/mRNA anti-correlations to identify clinically and genetically different TNBC subclasses. We also assessed miRNA signatures as potential regulators of TNBC subclass-specific gene expression networks defined by expression of canonical signal pathways.

Tissue specific miRNAs and mRNAs were identified for normal vs tumor vs mets comparisons. miRNA signatures correlated with prognosis were identified and predicted anti-correlated targets within the mRNA profile were defined. Two miRNA signatures (miR-16, 155, 125b, 374a and miR-16, 125b, 374a, 374b, 421, 655, 497) predictive of overall survival (P = 0.05) and distant-disease free survival (P = 0.009), respectively, were identified for patients 50 yrs of age or younger. By multivariate analysis the risk signatures were independent predictors for overall survival and distant-disease free survival. mRNA expression profiling, using the cancer-focused mRNA panel, resulted in clustering of TNBCs into 4 molecular subclasses with different expression signatures anti-correlated with the prognostic miRNAs.

Our findings suggest that miRNAs play a key role in triple negative breast cancer through their ability to regulate fundamental pathways such as: cellular growth and proliferation, cellular movement and migration, Extra Cellular Matrix degradation. The results define miRNA expression signatures that characterize and contribute to the phenotypic diversity of TNBC and its metastasis.