Induce Tumor Progression Research Articles

Mitochondrial defect drives non-autonomous tumour progression through Hippo signalling in Drosophila

Mitochondrial respiratory function is frequently impaired in human cancers. However, the mechanisms by which mitochondrial dysfunction contributes to tumour progression remain elusive. Here we show in Drosophila imaginal epithelium that defects in mitochondrial function potently induce tumour progression of surrounding tissue in conjunction with oncogenic Ras. Our data show that Ras activation and mitochondrial dysfunction cooperatively stimulate production of reactive oxygen species, which causes activation of c-Jun amino (N)-terminal kinase (JNK) signalling. JNK cooperates with oncogenic Ras to inactivate the Hippo pathway, leading to upregulation of its targets Unpaired (an interleukin-6 homologue) and Wingless (a Wnt homologue). Mitochondrial dysfunction in Ras-activated cells further cooperates with Ras signalling in neighbouring cells with normal mitochondrial function, causing benign tumours to exhibit metastatic behaviour. Our findings provide a mechanistic basis for interclonal tumour progression driven by mitochondrial dysfunction and oncogenic Ras.

Endotoxin induces proliferation of NSCLC in vitro and in vivo: role of COX-2 and EGFR activation.

Lung cancer is frequently complicated by pulmonary infections which may impair prognosis of this disease. Therefore, we investigated the effect of bacterial lipopolysaccharides (LPS) on tumor proliferation in vitro in the non-small cell lung cancer (NSCLC) cell line A549, ex vivo in a tissue culture model using human NSCLC specimens and in vivo in the A549 adenocarcinoma mouse model. LPS induced a time- and dose-dependent increase in proliferation of A549 cells as quantified by MTS activity and cell counting. In parallel, an increased expression of the proliferation marker Ki-67 and cyclooxygenase (COX)-2 was detected both in A549 cells and in ex vivo human NSCLC tissue. Large amounts of COX-2-derived prostaglandin (PG)E2 were secreted from LPS-stimulated A549 cells. Pharmacological interventions revealed that the proliferative effect of LPS was dependent on CD14 and Toll-like receptor (TLR)4. Moreover, blocking of the epidermal growth factor receptor (EGFR) also decreased LPS-induced proliferation of A549 cells. Inhibition of COX-2 activity in A549 cells severely attenuated both PGE2 release and proliferation in response to LPS. Synthesis of PGE2 was also reduced by inhibiting CD14, TLR4 and EGFR in A549 cells. The proliferative effect of LPS on A549 cells could be reproduced in the A549 adenocarcinoma mouse model with enhancement of tumor growth and Ki-67 expression in implanted tumors. In summary, LPS induces proliferation of NSCLC cells in vitro, ex vivo in human NSCLC specimen and in vivo in a mouse model of NSCLC. Pulmonary infection may thus directly induce tumor progression in NSCLC.

Alteration in E-Cadherin/β-Catenin Expression in Canine Melanotic Tumors

β-Catenin, encoded by the ctnnb1 gene, plays a critical role in intercellular adhesion, and its altered expression has been implicated in tumor progression in humans and animals. The aims of this study were to examine the alterations in β-catenin expression in canine melanoma as well as the causes of these changes (eg, E-cadherin or exon 3 mutations) and to compare identified changes between skin and oral melanomas. Forty-two primary canine skin and oral melanoma tissue samples were used in the study. The expression levels of ctnnb1 and the levels of E-cadherin/β-catenin complex in the tissues were determined by semiquantitative RT-PCR and immunohistochemistry, respectively. The mutational status of β-catenin exon 3 was examined by DNA sequencing. RT-PCR revealed higher levels of ctnnb1 expression in oral melanoma tissues compared with normal melanocytes, irrespective of sex or histopathological appearance of the tissue (ie, amelanotic vs melanotic). Immunohistochemistry revealed simultaneous loss of membrane E-cadherin/β-catenin complex and cytoplasmic accumulation of both proteins in 37 cases (84%). Intranuclear β-catenin was also detected in all tissues with reduced membrane β-catenin expression. In mutational analyses, one amelanotic oral melanoma showed 13 single nucleotide polymorphisms (SNPs); however, after protein translation, all the SNPs were silent mutations. The present study demonstrates that dysregulation of E-cadherin/β-catenin complexes is involved in both types of canine melanotic tumors and that the disruption of E-cadherin/β-catenin complexes and increased β-catenin may induce tumor progression and malignancy.

E2F1 loss induces spontaneous tumour development in Rb-deficient epidermis

The specific ablation of Rb1 gene in epidermis (Rb(F/F);K14cre) promotes proliferation and altered differentiation but does not produce spontaneous tumour development. These phenotypic changes are associated with increased expression of E2F members and E2F-dependent transcriptional activity. Here, we have focused on the possible dependence on E2F1 gene function. We have generated mice that lack Rb1 in epidermis in an inducible manner (Rb(F/F);K14creER(TM)). These mice are indistinguishable from those lacking pRb in this tissue in a constitutive manner (Rb(F/F);K14cre). In an E2F1-null background (Rb(F/F);K14creER(TM); and E2F1(-/-) mice), the phenotype due to acute Rb1 loss is not ameliorated by E2F1 loss, but rather exacerbated, indicating that pRb functions in epidermis do not rely solely on E2F1. On the other hand, Rb(F/F);K14creER(TM);E2F1(-/-) mice develop spontaneous epidermal tumours of hair follicle origin with high incidence. These tumours, which retain a functional p19(arf)/p53 axis, also show aberrant activation of β-catenin/Wnt pathway. Gene expression studies revealed that these tumours display relevant similarities with specific human tumours. These data demonstrate that the Rb/E2F1 axis exerts essential functions not only in maintaining epidermal homoeostasis, but also in suppressing tumour development in epidermis, and that the disruption of this pathway may induce tumour progression through specific alteration of developmental programs.

Silencing of I k Bβ mRNA causes disruption of mitochondrial retrograde signaling and suppression of tumor growth in vivo

A number of studies show that mitochondrial DNA (mtDNA) depletion and attendant activation of retrograde signaling induces tumor progression. We have reported previously that activation of a novel nuclear factor-Kappa B pathway is critical for the propagation of mitochondrial retrograde signaling, which induces both phenotypic and morphological changes in C2C12 myoblasts and A549 lung carcinoma cells. In this study, we investigated the role of stress-induced nuclear factor-Kappa B in tumor progression in xenotransplanted mice. We used a retroviral system for the inducible expression of small interfering RNA against IkBα and IkBβ mRNAs. Expression of small interfering RNA against IkBβ markedly impaired tumor growth and invasive ability of mtDNA-depleted C2C12 myoblasts and also thwarted anchorage-independent growth of the cells. Knockdown of IkBα mRNA, however, did not have any modulatory effect in this cell system. Moreover, expression of small interfering RNA against IkBβ reduced the expression of marker genes for retrograde signaling and tumor growth in xenografts of mtDNA-depleted cells. Our findings demonstrate that IkBβ is a master regulator of mitochondrial retrograde signaling pathway and that the retrograde signaling plays a role in tumor growth in vivo. In this regard, IkBβ supports the tumorigenic potential of mtDNA-depleted C2C12 cells.

Abstract LB-467: miR-135b and miR-210 induce invasion and distant metastasis by targeting SIAH1 and SETD2 in colorectal cancer

Abstract The metastatic spread of tumor cells is ultimately responsible for the vast majority of cancer related mortality. In the attainment of a metastatic phenotype, several intricately interwoven processes are involved that lead to uncontrolled proliferation, loss of intracellular adhesions, extracellular matrix degradation, intravasation and dissemination into distant organs. Therefore, an improved understanding of molecular mechanisms which regulate metastatic transformation and progression of the cancer cells is of paramount importance. In this present study we performed miRNA-microarray analysis of six patient samples comprising normal, primary tumor and distant metastasis tissues, where we found miR-135b, miR-210, miR-378, miR-19a to be significantly up-regulated in both tumor and metastasized tissues as compared to the respective normal equivalents. We validated miR-135b and -210 in a series of 30 colorectal patients, in which we were able to demonstrate an increased expression in tumor as compared to normal tissues (p=0.008 and p=0.03, respectively). Forced in vitro expression of these miRNAs resulted in increased migration and invasion of Rko, SW480 and SW620 colorectal cancer (CRC) cell lines. Additionally, these cells manifested a gain of mesenchymal marker (N-cadherin) and a loss of epithelial marker (E-cadherin) expression at the protein level. Furthermore, of the several predicted targets identified, through luciferase, RT-PCR and Western blot analysis we found SIAH1 and SETD2 to be regulated by miR-135b and -210, respectively. Furthermore, in vivo, chorioallantoic membrane (CAM) metastasis assays revealed that miR-135b and miR-210 significantly induce distant metastasis to the lungs and liver (p=0.05). Our preliminary findings suggest that miR-135b and 210 play important roles in inducing tumor progression and may be useful as potential targets for mitigating metastatic spread Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-467. doi:1538-7445.AM2012-LB-467

Abstract 5401: The influences of morphine on dendritic cell-mediated immunity

Abstract Morphine is a widely-used drug for analgesics and drug abuse. Previous studies have also demonstrated that the widely used as an anesthetic agent as well as adjuvant for the treatment of cancer pain and neuropathic pain, will bring harmful effects on specific immune system. Furthermore, the suppressed immune function may lead to postoperative infection and postoperative dissemination of carcinoma. Our research team has confirmed that morphine could promote tumor growth in naïve immunocompromised mice in our previous project, and morphine could suppress the proliferative ability of T lymphocytes even erased the tumor protection effects enhanced by tumor vaccines in vivo. However, these apoptotic phenomena could not explain the complete reasons that morphine induced tumor progression. The antigen processing and presenting activity enhanced by antigen presenting cells is the main cause in tumor development, especially in dendritic cells. The tumorgenesis is always associated with the low antigen presentation activity, and it results the poor recognization by cytotoxic T cells even causes the immuno-escape responses. In the present study, we confirmed that the efficiency of bone marrow monocytes differentiate into dendritic cells was significantly decreased after morphine stimulation. Under high dose morphine treatment, more than 30 % of differentiation efficiency was eliminated in 6 days incubation. Besides, the expression of co-stimulation factor CD80 and CD86 were both decrease after morphine treatment. Furthermore, cytokine expression including IL-6 and TNF-α were both inhibited, however, only IL-10 was slightly increase after morphine stimulation. Besides, the antigen processing and presenting activity of ex-vivo bone marrow-derived dendritic cells were reduced after morphine stimulation. These results suggested that morphine might reduce the process of dendritic cells maturation. These results provided the complete molecular mechanism and the correlation between morphine and immunity. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5401. doi:1538-7445.AM2012-5401

Consumption of high-fat diet induces tumor progression and epithelial–mesenchymal transition of colorectal cancer in a mouse xenograft model

Epidemiologic studies suggest that intake of high-fat diet (HFD) promotes colon carcinogenesis. Epithelial–mesenchymal transition (EMT) and inflammation play important roles during tumor progression of colorectal cancer (CRC). Oncogenic pathways such as phosphatidylinositol-3-kinase (PI3K)/Akt/mTOR and mitogen-activated protein kinase (MAPK)/ERK signaling cascades induce EMT and inflammation in cancer. No experimental evidence has been demonstrated regarding HFD-mediated tumor progression including EMT in CRC so far. Our results demonstrated that HFD consumption could induce tumor growth and progression, including EMT and inflammation, in a mouse xenograft tumor model. The molecular mechanisms were through activation of MAPK/ERK and PI3K/Akt/mTOR signaling pathways. HFD induced up-regulation of cyclooxygenase-2, cyclin D1 and proliferating cell nuclear antigen proteins concomitant with increases in expression of nuclear factor-κB p65 (RelA) and β-catenin proteins. Surprisingly, HFD consumption could suppress p21CIP1/WAF1 expression through increases in nuclear histone deacetylase complex (HDAC). Moreover, HFD could mediate the disassembly of E-cadherin adherent complex and the up-regulation of Vimentin and N-cadherin proteins in tumor tissues. Taken together, our novel findings support evidence for HFD-mediated modulation of HDAC activity and activation of oncogenic cascades, which involve EMT and inflammation in CRC, playing important roles in tumor growth and progression in a mouse xenograft model.

The Enzymatic Activity of Lysyl Oxidas-like-2 (LOXL2) Is Not Required for LOXL2-induced Inhibition of Keratinocyte Differentiation

Lysyl oxidase-like-2 (LOXL2) induces tumor progression and fibrosis. It also inhibits the differentiation of keratinocytes promoting development of squamous cell carcinomas. Stimulation of HaCaT skin keratinocytes with exogenous LOXL2 or overexpression of LOXL2 in these cells inhibits their differentiation as manifested by inhibition of calcium or vitamin D-induced involucrin expression. The inhibition was abrogated by the LOXL2 function-blocking monoclonal antibody AB0023 as well as by an anti-LOXL2 polyclonal antibody. Surprisingly, a point-mutated form of LOXL2 (LOXL2(Y689F)) lacking enzymatic activity, as well as a LOXL2 deletion mutant lacking the entire catalytic domain, also inhibited calcium or vitamin D-induced up-regulation of involucrin expression, suggesting that the enzymatic activity of LOXL2 is not required for this activity. This conclusion was supported by experiments that showed that β-aminoproprionitrile, an irreversible competitive inhibitor of the enzymatic activity of all lysyl oxidases, is unable to abolish the LOXL2-induced inhibition of HaCaT cell differentiation. The activity of LOXL2(Y689F) required the presence of the fourth scavenger receptor-cysteine-rich (SRCR) domain of LOXL2, which is also the binding target of AB0023. Epitope-tagged LOXL2(Y689F) was internalized at 37 °C by HaCaT cells. The internalization was inhibited by AB0023 and by competition with unlabeled LOXL2, suggesting that these cells may express a LOXL2 receptor. Our results suggest that agents that inhibit the enzymatic activity of LOXL2 may not suffice to inhibit completely the effects of LOXL2 on complex processes that involve altered states of cellular differentiation.

The Role of Mast Cells on Angiogenesis in Oral Squamous Cell Carcinoma

Objective: Angiogenesis or neovascularization has long been known to aid in progression and metastasis of malignant tumors. Tumor angiogenesis is a complex event mediated by angiogenic factors released from cancer cells and or by host immune cells. Mast cells may induce tumor progression and potentiate metastasis by stimulating angiogenesis. The purpose of the present study was to validate topographic distribution of micro vessel density (MVD) and mast cell density (MCD) and help to elucidate the possible role of mast cells in tumor angiogenesis and correlating this with advanced disease parameters. Study Design: MVD and MCD were investigated in tumor specimens from 30 patients diagnosed with different histologic grades of oral squamous cell carcinoma (OSCC). Intratumor vessels were stained with collagen Type IV antibody and mast cells with Toluidine blue before being measured by light microscopy. Results: There was a significant correlation between MVD and disease progression and number of blood vessels increased from well to poorly differentiated OSCC where as MCD decreased. Conclusions: These findings suggest that angiogenesis indeed occur in OSCC and might be used as an index to inflect the aggression of the disease however mast cells make up only a part of complex process of angiogenesis along with other factors secreted by tumor. Key words:Angiogenesis, mast cells, oral squamous cell carcinoma, progression, metastasis.

TGF-β Receptor II Loss Promotes Mammary Carcinoma Progression by Th17-Dependent Mechanisms

We report that IL-17 significantly increases the secretion of CXCL1 and CXCL5 from mammary carcinoma cells, which is downregulated by TGF-β through the type II TGF-β receptor (TβRII). Carcinoma cells with conditional knockout of TβRII (Tgfbr2(KO)) have enhanced sensitivity to IL-17a in the stimulation of chemokine secretion. During polyoma middle T (PyMT) induced tumor progression, levels of Th17 inducing cytokines TGF-β, IL-6, IL-23 were increased in PyMT/Tgfbr2(KO) tumors, which was associated with an increased number of Th17 cells. IL-17 increased the suppressive function of MDSCs on T cells through the upregulation of Arg, IDO, and COX2. Treatment of PyMT/Tgfbr2(KO) mice with anti-IL-17 Ab decreased carcinoma growth and metastatic burden. Analysis of human breast cancer transcriptome databases showed a strong association between IL-17 gene expression and poor outcome in lymph node positive, estrogen receptor negative or luminal B subtypes suggesting potential therapeutic approaches.

Abnormalities of the Wnt/β-catenin signalling pathway induce tumour progression in sporadic desmoid tumours: correlation between β-catenin widespread nuclear expression and VEGF overexpression

To analyse the correlation between β-catenin and vascular endothelial growth factor (VEGF) in sporadic desmoid tumours. The correlation between β-catenin aberrant expression and VEGF overexpression was examined and microvessel density (MVD) assessed by immunohistochemical expression of CD31 in 74 samples (63 primary and 11 recurrent samples, 63 patients) of sporadic desmoid tumours without familial adenomatous polyposis (FAP). β-catenin gene mutation and mRNA expression of VEGF was then examined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). There was a statistically significant correlation between widespread nuclear expression of β-catenin and overexpression of VEGF in all desmoid tumours (P = 0.04, Fisher's exact test). MVD in recurrent tumours was significantly higher than that in primary tumours. Abnormalities of β-catenin and VEGF overexpression play an important role in the neoplastic progression of sporadic desmoid tumours.

Abstract 2052: Inhibition of aldose reductase prevents hypoxic stress signaling in human colon cancer cells

Abstract Hypoxia, a hallmark of invasive solid tumors and increased angiogenesis, is strongly associated with the progression of malignant phenotypes, poor prognosis, and resistance to chemo and radiation therapies. In a variety of cancers, hypoxic stress-induces inflammatory signaling which is mediated by specific cytokines, chemokines and growth factors. We have recently shown that inhibition of aldose reductase (AR), an enzyme that catalyzes the reduction of lipid aldehydes and their glutathione conjugates, prevents human colon cancer cell growth in culture as well as in nude mice xenografts by inhibiting the NF-kB-dependent activation of oxidative stress-mediated inflammatory and carcinogenic markers. However, the role of AR in mediating hypoxic stress signals is not known. We therefore investigated the molecular mechanisms by which AR inhibition prevents the hypoxia-induced human colon cancer cells growth and invasion. Our results indicate that AR inhibition by pharmacological inhibitor fidarestat or ablation by AR specific siRNA prevents hypoxia-induced proliferation of HT29 colon cancer cells. Further, hypoxia- induced increase in the level of HIF1a in HT29 cells was significantly decreased by AR inhibition. During hypoxic conditions treatment of HT29 cells with AR inhibitor, fidarestat significantly decreased the expression of VEGF, a down target of HIF1a, at both mRNA and protein levels and also prevented the activation of PI3K/AKT and GSK3b. Further, AR inhibition also prevented hypoxia-induced inflammatory molecules such as Cox-2 and PGE2 and expression of extracellular matrix proteins such as MMP2, vimentin, uPAR and LOX2. In addition, AR inhibition also prevented the hypoxia -induced tube formation (angiogenesis) in vascular endothelial cells. In conclusion, our results indicate that AR mediates hypoxia -induced tumor progression, invasion and angiogenesis which can be prevented by AR inhibition or ablation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2052. doi:10.1158/1538-7445.AM2011-2052

Abstract 3972: Regulation of microRNA expression by hepatocyte growth factorin human head and neck sqaumous cell carcinoma (HNSCC)

Abstract Introduction: Hepatocyte growth factor (HGF) is a multifunctional growth factor that acts as mitogen, motogen, and/or morphogen in a variety of cells. MET, a specific receptor tyrosine kinase for HGF, is up-regulated in various tumors including human head and neck squamous cell carcinoma (HNSCC) and its signal transduction induces tumor progression and invasion. However, how HGF affects the expression of downstream functional gene expression has not yet been elucidated in detail. MicroRNAs (miRNAs) are non-coding small RNAs that regulate posttranscriptional gene expression by interfering the translation of target mRNAs. Aberrant expression of miRNA is known to induce various human tumors including HNSCC, but the regulation of miRNA expression is still unknown. In this study, we examined the expression of miRNAs with or without HGF stimulation in human HNSCC cell line HSC3 and the expression of their putative target genes was evaluated. Methods: Human HNSCC cell line HSC3 was cultured with or without HGF for designated periods. Alteration of miRNA expression was examined by miRNA microarray analysis. Validation study of miRNAs showing altered expression was performed by quantitative RT-PCR (qRT-PCR). The expression of putative target mRNAs and their translated proteins were examined by qRT-PCR and western blot analysis, respectively. Results: The expression of several miRNAs including let-7a, miR-16, and miR-205, which are already known as tumor-suppressive miRNAs, was altered after HGF stimulation by miRNA microarray. Among them, we focused on miR-200c and miR-27b which were drastically down-regulated after HGF stimulation, because of their unique target mRNAs involving HGF-mediated functional molecules. The expression of ZEB1, a target mRNA for 200c, was up-regulated 3hr after HGF stimulation and that of E-cadherin, a downstream molecule of ZEB1, was up-regulated 12hr after HGF stimulation. The expression of ST14/matriptase, an activation enzyme of HGF and a target mRNA for miR-27b, was not statistically altered after HGF stimulation, but the protein level was drastically up-regulated 12hr after HGF stimulation. These changes were attenuated in part by the addition of oligo pre-mi27b or pre-miR200c into the culture medium. Conclusion: Our present results suggest that miR-200c down-regulated by HGF might play an important role for epithelial-mesenchymal transition (EMT), through up-regulation of ZEB1 followed by down-regulation of E-cadherin. In addition, it was also suggested that miR-27b down-regulated by HGF might induce auto-activation of HGF in HNSCC. These alterations of miRNA expression by HGF stimulation could be induce the enhanced progressive and invasive characteristics of HNSCC. This is a first report that HGF may directly regulate some miRNAs that affect the expression of HGF-mediated downstream functional molecules. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3972. doi:10.1158/1538-7445.AM2011-3972

A Novel HSP90 Inhibitor Delays Castrate-Resistant Prostate Cancer without Altering Serum PSA Levels and Inhibits Osteoclastogenesis

Prostate cancer responds initially to antiandrogen therapies; however, progression to castration-resistant disease frequently occurs. Therefore, there is an urgent need for novel therapeutic agents that can prevent the emergence of castrate-resistant prostate cancer (CRPC). HSP90 is a molecular chaperone involved in the stability of many client proteins including Akt and androgen receptor (AR). 17-Allylamino-17-demethoxy-geldanamycin (17-AAG) has been reported to inhibit tumor growth in various cancers; however, it induces tumor progression in the bone microenvironment. Cell growth, apoptosis, and AR transactivation were examined by crystal violet assay, flow cytometric, and luciferase assays, respectively. The consequence of HSP90 therapy in vivo was evaluated in LNCaP xenograft model. The consequence of PF-04928473 therapy on bone metastasis was studied using an osteoclastogenesis in vitro assay. PF-04928473 inhibits cell growth in a panel of prostate cancer cells, induces cell-cycle arrest at sub-G(1), and leads to apoptosis and increased caspase-3 activity. These biological events were accompanied by decreased activation of Akt and Erk as well as decreased expression of Her2, and decreased AR expression and activation in vitro. In contrast to 17-AAG, PF-04928473 abrogates RANKL-induced osteoclast differentiation by affecting NF-κB activation and Src phosphorylation. Finally, PF-04929113 inhibited tumor growth and prolonged survival compared with controls. Surprisingly, PF-04929113 did not reduce serum prostate-specific antigen (PSA) levels in vivo; in parallel, these decrease in tumor volume. These data identify significant anticancer activity of PF-04929113 in CRPC but suggest that serum PSA may not prove useful as pharmacodynamic tool for this drug.

Angiotensin II induces tumor progression and fibrosis in intrahepatic cholangiocarcinoma through an interaction with hepatic stellate cells

Intrahepatic cholangiocarcinoma (ICC) is characterized as a highly fatal tumor with poor prognosis because of its strong progression, early invasion, widespread metastasis and rich cancerous stroma. Although it is widely accepted that fibroblasts facilitate stromal fibrosis and tumor progression, the mechanisms of the interaction between cancer cells and activated fibroblasts have not been fully elucidated thus far. In this study, we demonstrate the presence of angiotensin II (AngII) in ICC tissues and explore the interaction between hepatic stellate cells (HSCs) and ICC cells as one of the sources of stromal fibrosis and tumor progression through the interaction of the AngII/AngII type 1 receptor (AT-1) axis. The concentrations of AngII in ICC tissues were significantly higher than those of HCC and normal liver. Two human ICC cell lines (HuCCT-1, CCKS-1) and a human HSC cell line (LI-90) expressed AT-1 mRNA and protein. The proliferative activity of ICC cells and HSCs to which AngII was added dose-dependently increased and AT-1 antagonist inhibited the proliferative effects. HSCs to which AngII was added showed a higher expression of α-smooth muscle actin (α-SMA, a marker of activated HSCs and myofibroblasts), glial fibrillary acidic protein (GFAP, a specific marker of HSCs) and collagen type I than control cells. AT-1 antagonist also inhibited the activation and transformation of HSCs stimulated by AngII. These findings suggested that locally formed AngII in ICC tissues plays a role in the proliferation and activation of ICC cells and HSCs expressing AT-1 as a growth factor in autocrine and paracrine fashions. Our mechanistic findings provide the first insight into an autocrine and paracrine AngII-initiated signaling pathway that regulates ICC proliferation and fibrosis.

MMP-3 and MMP-9 Gene Transfer Decrease Growth and Angiogenesis in Breast Cancer Xenografts In Vivo.

Abstract Matrix metalloproteinases (MMPs) are largely implicated in tumor angiogenesis and metastasis due to their extracellular matrix (ECM) degrading capacities. Although MMP activity generally is discussed in terms of facilitating tumor invasion, MMP inhibition in clinical trials has failed. Moreover, increasing amounts of data show that MMPs may inhibit tumor progression by generation of potent anti-angiogenic factors such as endostatin from the tumoral stroma. We have previously shown that intratumoral gene transfer of MMP-9 induced tumor regression and reduced angiogenesis of breast cancer in vivo. If MMP activity induces tumor progression or regression may depend on type of MMP or expression levels of MMP in the tumor tissue. In this study we treated established breast cancers in nude mice with adenovirus vectors carrying the human genes of MMP-3 or MMP-9 in a dose response manner. Microdialysis was used to sample endostatin in situ and tumor growth was monitored for 35 days. Tumors in mice treated with low-dose of either MMP-3 or MMP-9 vectors exhibited tumor stasis throughout the experiment whereas high-dose gene transfer of either MMP-3 or MMP-9 induced significant tumor regression compared to controls treated with empty adenovirus vectors. The extracellular in vivo levels of endostatin were significantly increased in tumors treated with adenovirus carrying the MMP genes compared to controls. Tumors treated with high-dose MMP vectors also exhibited decreased microvessel area. Our results propose that increased expression of MMP-3 and MMP-9 have therapeutic effects of established breast cancer in a dose dependent manner where a slight increase of MMP expression results in tumor stasis and a high expression of either MMP-3 or MMP-9 by gene transfer results in a potent tumor regression. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4164.

Role of IKK-NFκB signaling pathway in inflammation and tumorigenesis

There have been increasing evidences supporting the relationship between inflammation and tumor,but the exact molecular mechanism correlating the two remaines nebulous. Recently,it is found that IKK- NFκB signaling pathway plays a critical role in inflammation-associated tumor. The major pro-tumorigenic func-tion of IKK-NFκB signaling pathway is to upregulate production of key pro-inflammatory cytokines and/or to in- duce the expression of genes coding for anti-apoptosis proteins. In addition, abnormal microenvironment around tumor can activate IKK-NFκB signaling pathway,whose target genes contribute to tumorigenesis. This review fo-cuses on IKKP-NFκB signaling pathway, which is a crucial mediator in inflammation - induced tumor promotion and progression, as well as an important modulator of tumor me-tastasis. Key words: NF-κappa B; Inflammation; Neoplastic processes

Predictive testing for erythropoietin induced tumor progression in head and neck cancer

11007 Background: Although anemia is an independent poor prognostic factor in cancer, its correction using erythropoietin (Epo) may promote cancer progression and reduce survival, as suggested by several recent Phase III trials. We tested whether measuring Epo receptor (EpoR) mRNA levels in head and neck cancer could identify patients susceptible to Epo induced tumor growth. We also examined whether endogenous Epo might stimulate tumor growth. Methods: We measured EpoR mRNA levels in tumors from a previously reported Phase III trial in which 351 patients irradiated for head and neck cancer were randomized to Epo or placebo (Henke et al., Lancet 2003). 154 of these tumors had been evaluated previously with a polyclonal antibody raised against the human EpoR (C20) (Henke et al., J Clin Oncol 2006), but which also cross reacts with non-EpoR proteins (Elliott et al., Blood 2006). EpoR mRNA levels were measured in 106 tumors. We examined the relationship between EpoR mRNA level and locoregional progression free survival (LPFS), the primary study endpoint, in subjects assigned to Epo versus placebo. For patients enrolled in the placebo arm we also compared baseline serum Epo levels, C20 status, EpoR mRNA levels, and LPFS. Results: Epo-treated patients with unresected tumors that expressed above-median EpoR mRNA levels experienced a reduction in LPFS compared to the placebo group (p=0.02, n=s effect was not observed in patients with unresected tumors that expressed below-median EpoR mRNA levels (p=0.80, n=14). EpoR mRNA levels had no effect in patients with completely resected or partially resected tumors. In placebo patients with unresected or incompletely resected tumors, increased Epo levels were associated with impaired LPFS if their tumors were C20 positive (p=0.02, n=22), and improved LPFS if their tumors were C20 negative (p=0.09, n=15). C20 status and EpoR mRNA levels did not correlate (r=−0.11). Conclusion: Adverse effects of Epo on tumor progression may depend on tumor EpoR expression. Whether a relationship exists between other C20 targets and Epo induced tumor progression deserves further exploration. Our findings present clear hypotheses that should be tested in archival tumors from other Phase III trials. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Expert Testimony Other Remuneration Hoffman-La Roche

The way to safer liver resection in cirrhotic patients: is Cardiotrophin‐1 the future miracle drug?

The way to safer liver resection in cirrhotic patients: is Cardiotrophin‐1 the future miracle drug?