P2Y2 receptor promotes cell invasion and metastasis in prostate cancer cells

Background:

Our previous study demonstrated that extracellular adenosine 5′-triphosphate (ATP) stimulated prostate cancer cell invasion via P2Y receptors. However, the purinergic receptor subtype(s) involved in this process remains unclear. Here we aimed to determine whether P2Y2, one subtype of P2Y receptors, was involved in the invasion and metastasis of prostate cancer cells, and elucidated the underlying mechanism.

Methods:

RNAi was introduced to silence the expression of P2Y2. In vitro invasion and migration assays and in vivo experiments were carried out to examine the role of P2Y2 receptor in cell invasion and metastasis. cDNA microarray was performed to identify the differentially expressed genes downstream of ATP treatment.

Results:

P2Y2 was significantly expressed in the prostate cancer cells. Knockdown of P2Y2 receptor suppressed cell invasion and metastasis in vitro and in vivo. Further experiments identified that ATP could promote IL-8 and Snail expression and inhibit E-cadherin and Claudin-1 expression. Knockdown of P2Y2 receptor affected the expression of these EMT/invasion-related genes in vitro and in vivo.

Conclusion:

P2Y2 receptor promotes cell invasion and metastasis in prostate cancer cells via some EMT/invasion-related genes. Thereby, P2Y2 receptor could be a potential therapeutic target for the treatment of prostate cancer.     

Farnesoid X receptor, overexpressed in pancreatic cancer with lymph node metastasis promotes cell migration and invasion

Background:

Lymph node metastasis is one of the most important adverse prognostic factors for pancreatic cancer. The aim of this study was to identify novel lymphatic metastasis-associated markers and therapeutic targets for pancreatic cancer.

Methods:

DNA microarray study was carried out to identify genes differentially expressed between 17 pancreatic cancer tissues with lymph node metastasis and 17 pancreatic cancer tissues without lymph node metastasis. The microarray results were validated by real-time PCR. Immunohistochemistry and western blotting were used to examine the expression of farnesoid X receptor (FXR). The function of FXR was studied by small interfering RNA and treatment with FXR antagonist guggulsterone and FXR agonist GW4064.

Results:

Farnesoid X receptor overexpression in pancreatic cancer tissues with lymph node metastasis is associated with poor patient survival. Small interfering RNA-mediated downregulation of FXR and guggulsterone-mediated FXR inhibition resulted in a marked reduction in cell migration and invasion. In addition, downregulation of FXR reduced NF-κB activation and conditioned medium from FXR siRNA-transfected cells showed reduced VEGF levels. Moreover, GW4064-mediated FXR activation increased cell migration and invasion.

Conclusions:

These findings indicated that FXR overexpression plays an important role in lymphatic metastasis of pancreatic cancer and that downregulation of FXR is an effective approach for inhibition of pancreatic tumour progression.     

Nestin is a novel target for suppressing pancreatic cancer cell migration, invasion and metastasis

Nestin, is a class VI intermediate filament (IF) that is expressed in 30% of pancreatic ductal adenocarcinoma (PDAC) cases, and its expression in PDAC positively correlates with peripancreatic invasion. An expression vector carrying a short hairpin RNA (shRNA) targeting nestin was stably transfected into PANC-1 and PK-45H human pancreatic cancer cells, which express high nestin levels. Alterations in morphology and alignment of actin filaments and α-tubulin were examined by phase-contrast and immunocytochemistry. Effects on cell growth, migration in scratch and Boyden chamber assays, invasion, cell adhesion, and in vivo growth were determined. Differences in mRNA levels were examined by arrays. Nestin shRNA-transfected cells exhibited decreased nestin expression, a sheet-like appearance with tight cell-cell adhesion, increased expression of filamentous F-actin and E-cadherin, and attenuated migration and invasion, both of which were enhanced following nestin re-expression. Expression of α-tubulin, and in vitro cell growth and adhesion were not altered by nestin down-regulation, whereas hepatic metastases were decreased. Thus, nestin plays important roles in pancreatic cancer cell migration, invasion and metastasis by selectively modulating the expression of actin and cell adhesion molecules, and may therefore be a novel therapeutic target in PDAC.     

FBXO31 promotes cell proliferation,metastasis and invasion in lung cancer

FBXO31 is a member of F-box family which is involved in diverse biological functions and development of disease. Recent reports in breast cancer, hepatocellular carcinoma and ovarian cancer demonstrated inhibitory effect of FBXO31 on proliferation and tumorigenesis. However, the function of FBXO31 is not analyzed in lung cancer so far. In this study, we reported that expression of FBXO31 was higher in lung cancer tissues compared with non-cancerous lung tissues, and that higher expression of FBXO31 was significantly associated with tumor size, tumor infiltration, clinical stages and lymph node metastasis. In addition, exogenous expression of FBXO31 promoted cell growth, metastasis and invasion in A549 cells. Conversely, silencing FBXO31 by specific siRNA caused inhibitory effect on cell growth, metastasis and invasion. Moreover, tumorigenicity assays in nude mice showed FBXO31 promoted tumor growth in vivo. In conclusion, our data suggest FBXO31 promotes cell proliferation, metastasis and invasion in lung cancer.     

Hepsin promotes prostate cancer progression and metastasis

The majority of cancer-related deaths are associated with metastasis; however, little is known about the mechanisms of this process. Hepsin is a cell surface serine protease that is markedly upregulated in human prostate cancer; however, the functional significance of this upregulation is unknown. We report here that hepsin overexpression in prostate epithelium in vivo causes disorganization of the basement membrane. Overexpression of hepsin in a mouse model of nonmetastasizing prostate cancer has no impact on cell proliferation, but causes disorganization of the basement membrane and promotes primary prostate cancer progression and metastasis to liver, lung, and bone. We provide in vivo evidence that upregulation of a cell surface serine protease in a primary tumor promotes cancer progression and metastasis.     

Phospholipase PLA2G7, associated with aggressive prostate cancer, promotes prostate cancer cell migration and invasion and is inhibited by statins

Prostate cancer is the second leading cause of cancer mortality in men in developed countries. Due to the heterogeneous nature of the disease, design of novel personalized treatments is required to achieve efficient therapeutic responses. We have recently identified phospholipase 2 group VII (PLA2G7) as a potential drug target especially in ERG oncogene positive prostate cancers. Here, the expression profile of PLA2G7 was studied in 1137 prostate cancer and 409 adjacent non-malignant prostate tissues using immunohistochemistry to validate its biomarker potential and putative association with disease progression. In order to reveal the molecular alterations induced by PLA2G7 impairment, lipidomic and gene expression profiling was performed in response to PLA2G7 silencing in cultured prostate cancer cells. Moreover, the antineoplastic effect of statins combined with PLA2G7 impairment was studied in prostate cancer cells to evaluate the potential of repositioning of in vivo compatible drugs developed for other indications towards anti-cancer purposes. The results indicated that PLA2G7 is a cancer-selective biomarker in 50 % of prostate cancers and associates with aggressive disease. The alterations induced by PLA2G7 silencing highlighted the potential of PLA2G7 inhibition as an anti-proliferative, pro-apoptotic and anti-migratorial therapeutic approach in prostate cancer. Moreover, the anti-proliferative effect of PLA2G7 silencing was potentiated by lipid-lowering statins in prostate cancer cells. Taken together, our results support the potential of PLA2G7 as a biomarker and a drug target in prostate cancer and present a rationale for combining PLA2G7 inhibition with the use of statins in prostate cancer management.     

Osteoblasts in prostate cancer metastasis to bone

Metastasis to bone is common in lung, kidney, breast and prostate cancers. However, prostate cancer is unique in that bone is often the only clinically detectable site of metastasis, and the resulting tumours tend to be osteoblastic (bone forming) rather than osteolytic (bone lysing). The interaction between host cells and metastatic cancer cells is an important component of organ-specific cancer progression. How can this knowledge lead to the development of more effective therapies?     

Carboxypeptidase E promotes cancer cell survival,but inhibits migration and invasion

Carboxypeptidase E (CPE), a prohormone processing enzyme is highly expressed and secreted from (neuro)endocrine tumors and gliomas, and has been implicated in cancer progression by promoting tumor growth. Our study demonstrates that secreted or exogenously applied CPE promotes survival of pheochromocytoma (PC12) and hepatocellular carcinoma (MHCC97H) cells under nutrient starvation and hypoxic conditions, but had no effect on their proliferation. CPE also reduced migration and invasion of fibrosarcoma (HT1080) cells. We show that CPE treatment mediates survival of MHCC97H cells during metabolic stress by up-regulating the expression of anti-apoptotic protein BCL-2, and other pro-survival genes, via activation of the ERK1/2 pathway.     

SNAI1 overexpression induces stemness and promotes ovarian cancer cell invasion and metastasis

Ovarian cancer is the fifth most common cancer among women worldwide. Detection of metastasis of ovarian cancer is crucial for diagnosis and prolongs the life of patients. This study focused on whether SNAI1 overexpression relates to invasion of ovarian cancer in?vitro and in?vivo. Invasion, colony formation and wound healing assays and flow cytometric analysis were performed to test the invasion and proliferation of SKOV3 ovarian cancer cells after transfection. The effect of SNAI1 on ovarian cancer in vivo was validated using a murine xenograft model. In?vitro, SNAI1 upregulation led to an increased percent of CD133+ SKOV3 cells and promoted SKOV3 cell invasion and proliferation. In?vivo, the SNAI1 overexpression group showed the highest rate of tumor growth compared with SNAI2 and the control group (60 and 50%, respectively). Our results show that SNAI1 expression induces an increase in the number of CD133+ cells, a change important for the epithelial to mesenchymal transition and the proliferation in ovarian cancer. It is suggested that SNAI1 may serve as a novel target for ovarian cancer prediction and therapy.     

Management for bone metastasis of prostate cancer

The bone is the most common site of origin of distant metastasis in prostate cancer, and advanced prostate cancer has an extremely high rate of bone metastasis. Therefore, management of bone metastases is an important issue in the treatment of prostate cancer. Although relatively rare because the main characteristic of bone metastases is osteoblastic, pathological fracture and bone-related events, such as radiotherapy for the alleviation of pain and paralysis, are some of the major problems associated with bone metastases. To date, no aggressive therapy has been available to address these problems. However, because of the discovery of novel drugs such as zoledronic acid and denosumab, the use of drugs to control osteoclasts has become the standard treatment for bone metastasis. Management of bone metastases may take on new dimensions even in the near future because of the continuing development, of therapy, including the discovery of a new radium isotope and the development of targeted therapy drugs, such as dasatinib and cabozantinib. In this review, we describe the current management strategies, centering on zoledronic acid, potential new drugs, and the future prospect of bone metastasis therapy.     

Demethoxycurcumin inhibits cell proliferation, migration and invasion in prostate cancer cells

Curcumin (CUR) is a natural agent that has been demonstrated to effectively inhibit prostate cancer growth. However, natural CUR is relatively unstable and can be easily degraded in vivo. Therefore, it is essential to develop other stable curcuminoids. Demethoxycurcumin (DMC) is a candidate that has been verified in several tumor types and has potential for the treatment of prostate cancer. In the present study, we investigated the effects of DMC on proliferation, apoptosis and migration of PC-3 cells. MTT assay results indicated that DMC inhibited PC-3 cell viability in a dose- and time-dependent manner, and DMC induced G2/M phase arrest. Furthermore, PC-3 cells in DMC-treated groups had a higher apoptotic rate compared with DMSO-treated control. This effect may be due to the activation of the caspase-3 pathway. In DMC-treated groups, migrating and invasive cells were dramatically reduced (P<0.05). The activity of MMP-2, which is correlated with migration and invasion was also suppressed by DMC. These results indicated that DMC may inhibit PC-3 cell migration and invasion partially by affecting MMP-2 activity. In conclusion, DMC significantly inhibits proliferation, migration and invasion of cultured PC-3 cells, and this study may provide evidence for future in vivo studies and clinical use.     

Expression and functional role of CCR9 in prostate cancer cell migration and invasion.

PURPOSE: Metastasis is responsible for most cancer-related deaths; hence, therapies designed to minimize metastasis are greatly needed. The precise cellular and molecular mechanisms used by cancer cells for metastasis are not fully understood; however, the metastatic spread of neoplastic cells is probably related to the ability of these cells to migrate, invade, home, and survive locally. The migration of tumor cells shares many similarities with leukocyte trafficking, which is regulated by chemokine receptor-ligand interactions. The current study evaluates the molecular mechanisms of CCL25 and CCR9 in prostate cancer cell migration and invasion. EXPERIMENTAL DESIGN: In the current study, real-time quantitative polymerase chain reaction, flow cytometry analysis, and in vitro migration as well as invasion chamber analysis (with and without antibody-mediated inhibition) were used to ascertain the biological and functional significance of CCR9 expression by normal prostatic epithelial cells (PrEC) or prostate cancer cell lines (LNCaP-10995 and PC3). RESULTS: We report that functional CCR9 is highly expressed by LNCaP cells and modestly, yet significantly, expressed by PC3 cells when compared with PrEC cells. Neutralization of CCL25-CCR9 interactions impaired the migration and invasion potential of the LNCaP and PC3 cell lines. CCL25 differentially modulated the expression of collagenase-1 or matrix metalloproteinase (MMP)-1, collagenase-3 (MMP-13), stromalysin-2 (MMP-10), stromalysin-3 (MMP-11), and gelatinase-A (MMP-2), but not MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, or MMP-14 in prostate cancer cells. CONCLUSIONS: These studies suggest that the expression and activation of CCR9 affect cancer cell migration, invasion, and MMP expression, which together may affect prostate cancer metastasis.     

Macrophage migration inhibitory factor promotes tumor invasion and metastasis via the Rho-dependent pathway.

PURPOSE: Macrophage migration inhibitory factor (MIF) plays an important role not only in the immune system but also in tumorigenesis. In this study, we investigated the potential role of MIF in association with tumor invasion and metastasis. METHODS: To assess the function of MIF, we knocked down the MIF mRNA using small interfering RNA (siRNA). Twenty-one base siRNA specific for the mRNA sequence of mouse MIF was introduced to a murine colon cancer cell line, colon 26. Tumor cell invasion was evaluated using a transwell method (8-microm pores) coated with Matrigel on the upperside membrane and with fibronectin on the underside membrane. Moreover, we investigated the signal transduction of lysophosphatidic acid (LPA) relevant to the Rho-dependent pathway and further examined the effect of MIF siRNA on this signal transduction system. In vivo, the tumor cells were pretreated with MIF siRNA and injected into the portal vein, and the effects on metastasis to the liver were evaluated. RESULTS: We found that MIF siRNA markedly reduced the invasion of the cells from the upperside to lowerside membranes. We revealed that the Rho-dependent pathway activated by LPA was suppressed by MIF siRNA. Next, we found that the tyrosine-phosphorylation of focal adhesion kinase and LPA-induced expressions of integrin beta1 were significantly suppressed by MIF siRNA. In vivo, metastasis to the liver was significantly inhibited by pretreatment of the cells with MIF siRNA. CONCLUSION: Taken together, these results suggest that MIF promotes tumor invasion and metastasis via the Rho-dependent pathway.     

Calcineurin promotes proliferation, migration, and invasion of small cell lung cancer

A novel role for calcineurin (Cn) has been reported recently regarding the oncogenic potential in pancreatic and colorectal cancer. The aim of this study was to investigate the putative causal role calcineurin could play in the development of lung cancer with bone metastases. We found that CnAα, an isoform of calcineurin, was significantly overexpressed in lung cancer tissues with bone metastasis as compared to tumors with non-bone metastases as investigated by RT-PCR. Strong nuclear staining of tumor cells was observed in small cell lung cancer tissues with bone metastasis. Conversely, cytoplasmic staining of tumor cells was observed in small cell lung cancer tissues with non-bone metastasis. Western blots of nuclear proteins from lung cancer tissues indicated that CnAα was highly expressed in lung cancer tissues with bone metastases, but not in those with non-bone metastases. In vitro, it was demonstrated that the CnAα gene obviously promoted cell proliferation and inhibited cell apotosis. The CnAα gene affected the cell cycle and promoted G1?S transition in SBC-3 cells. Transfection with the CnAα gene promoted cell migration and invasion. These results indicated that CnAα may affect the biological behavior of the human small cell lung cancer cell line SBC-3 in vitro and may be a candidate tumor promotor gene for developing bone metastases.     

miR-34a对结肠癌细胞SW480增殖、迁移和侵袭能力的影响及机制探讨

目的 探讨miR-34a对结肠癌细胞株SW480增殖、侵袭和迁移能力的影响及可能的作用机制。方法将miR-34a过表达慢病毒、空病毒载体转染SW480细胞,未做处理细胞作为空白对照组。Real-time PCR检测各组细胞内miR-34a的表达;CCK8法检测细胞增殖能力;划痕实验、Transwell小室实验检测细胞迁移和侵袭能力;Western blot实验检测细胞内E-cadherin和Vimentin蛋白表达。结果 与空病毒载体组及空白对照组相比,转染组细胞中miR-34a的表达增高,且细胞增殖效率、侵袭和迁移能力降低(P＜0.05),miR-34a使E-cadherin蛋白表达增加、Vimentin蛋白表达降低。结论 miR-34a可抑制结肠癌细胞SW480增殖、侵袭和迁移能力,并能影响E-cadherin和Vimentin的表达,miR-34a有望成为干预结肠癌转移和复发的分子靶点。