Elevated expression of N-myc downstream regulated gene 1 protein in glioblastomas reflects tumor angiogenesis and poor patient prognosis.

N-myc downstream regulated gene 1 (NDRG1) is a member of the NDRG family, of which four members (NDRG1, NDRG2, NDRG3, and NDRG4) have been identified. NDRG1 is repressed by c-MYC and N-MYC proto-oncogenes. NDRG1 is translated into a 43 kDa protein that is associated with the regulation of cellular stress responses, proliferation, and differentiation. In this study, we aimed to clarify the relationship between progression of glioblastoma (GB) IDH-wildtype and NDRG1 expression in tumor cells. We assessed the expression of NDRG1 in 41 GBs using immunostaining and evaluated its prognostic significance. NDRG1 expression by GBs was evaluated using Histoscore, which showed high and low scores in 23 and 18 cases, respectively. NDRG1-positive cells were strongly expressed in Ki-67 labeled proliferating tumor cells and CD105 positive proliferating microvessels around the area of palisading necrosis. Statistical analyses showed lower survival rates in the high-score group than the low-score group (P < 0.01). This study indicated that overexpression of NDRG1 by GB reflects tumor angiogenesis and poor patient prognosis.

Enhanced ALOX12 Gene Expression Predicts Therapeutic Susceptibility to 5-Azacytidine in Patients with Myelodysplastic Syndromes.

5-azacytidine (AZA), a representative DNA-demethylating drug, has been widely used to treat myelodysplastic syndromes (MDS). However, it remains unclear whether AZA's DNA demethylation of any specific gene is correlated with clinical responses to AZA. In this study, we investigated genes that could contribute to the development of evidence-based epigenetic therapeutics with AZA. A DNA microarray identified that AZA specifically upregulated the expression of 438 genes in AZA-sensitive MDS-L cells but not in AZA-resistant counterpart MDS-L/CDA cells. Of these 438 genes, the ALOX12 gene was hypermethylated in MDS-L cells but not in MDS-L/CDA cells. In addition, we further found that (1) the ALOX12 gene was hypermethylated in patients with MDS compared to healthy controls; (2) MDS classes with excess blasts showed a relatively lower expression of ALOX12 than other classes; (3) a lower expression of ALOX12 correlated with higher bone marrow blasts and a shorter survival in patients with MDS; and (4) an increased ALOX12 expression after AZA treatment was associated with a favorable response to AZA treatment. Taking these factors together, an enhanced expression of the ALOX12 gene may predict favorable therapeutic responses to AZA therapy in MDS.

N-Myc Downstream Regulated Gene-1 May Play an Important Role in the Prognosis of Ovarian Cancer, in Its Association with Beta-Catenin.

NDRG1 is a nickel- and calcium-inducible gene that plays important roles in the primary growth of malignant tumors, as well as in invasion and metastasis. This study investigated the associations of NDRG1 expression with cell adhesion and other clinicopathological factors in ovarian cancer. The clinical records of 123 women who underwent surgery for ovarian cancer in our institute were reviewed retrospectively. The expression of NDRG1, E-cadherin, and beta-catenin in surgical specimens were evaluated immunohistochemically. The NDRG1 expression level was significantly associated with beta-catenin expression, peritoneal metastasis outside the pelvic cavity, lymph node metastasis, and FIGO stages. The Kaplan-Meier analysis showed a significant association between the NDRG1 expression level and progression-free survival: high NDRG1 expression was related to poor survival. Our results suggest that the increased expression of NDRG1 is associated with cell adhesion and may be a poor prognostic indicator in women with ovarian cancer.

AXL/CDCP1/SRC axis confers acquired resistance to osimertinib in lung cancer.

Osimertinib, a third-generation EGFR-TKI, has nowadays been applied to non-small cell lung cancer harboring activated EGFR mutation with or without T790M, but ultimately develop resistance to this drug. Here we report a novel mechanism of acquired resistance to osimertinib and the reversal of which could improve the clinical outcomes. In osimertinib-resistant lung cancer cell lines harboring T790M mutation that we established, expression of multiple EGFR family proteins and MET was markedly reduced, whereas expression of AXL, CDCP1 and SRC was augmented along with activation of AKT. Surprisingly, AXL or CDCP1 expression was induced by osimertinib in a time-dependent manner up to 3 months. Silencing of CDCP1 or AXL restored the sensitivity to osimertinib with reduced activation of SRC and AKT. Furthermore, silencing of both CDCP1 and AXL increased the sensitivity to osimertinib. Either silencing of SRC or dasatinib, a SRC family kinase (SFK) inhibitor, suppressed AKT phosphorylation and cell growth. Increased expression of AXL and CDCP1 was observed in refractory tumor samples from patients with lung cancer treated with osimertinib. Together, this study suggests that AXL/SFK/AKT and CDCP1/SFK/AKT signaling pathways play some roles in acquired osimertinib resistance of non-small cell lung cancer.

NDRG1 activates VEGF-A-induced angiogenesis through PLCγ1/ERK signaling in mouse vascular endothelial cells.

Many diseases, including cancer, have been associated with impaired regulation of angiogenesis, of which vascular endothelial growth factor (VEGF)-A is a key regulator. Here, we test the contribution of N-myc downstream regulated gene 1 (NDRG1) to VEGF-A-induced angiogenesis in vascular endothelial cells (ECs). Ndrg1-/- mice exhibit impaired VEGF-A-induced angiogenesis in corneas. Tumor angiogenesis induced by cancer cells that express high levels of VEGF-A was also reduced in a mouse dorsal air sac assay. Furthermore, NDRG1 deficiency in ECs prevented angiogenic sprouting from the aorta and the activation of phospholipase Cγ1 (PLCγ1) and ERK1/2 by VEGF-A without affecting the expression and function of VEGFR2. Finally, we show that NDRG1 formed a complex with PLCγ1 through its phosphorylation sites, and the inhibition of PLCγ1 dramatically suppressed VEGF-A-induced angiogenesis in the mouse cornea, suggesting an essential role of NDRG1 in VEGF-A-induced angiogenesis through PLCγ1 signaling.

Targeting Phosphorylation of Y-Box-Binding Protein YBX1 by TAS0612 and Everolimus in Overcoming Antiestrogen Resistance.

Nuclear expression of Y-box-binding protein (YBX1) is closely correlated with clinical poor outcomes and drug resistance in breast cancer. Nuclear translocation of YBX1 is facilitated by YBX1 phosphorylation at serine 102 by AKT, p70S6K, and p90RSK, and the phosphorylated YBX1 (pYBX1) promotes expression of genes related to drug resistance and cell growth. A forthcoming problem to be addressed is whether targeting the phosphorylation of YBX1 overcomes antiestrogen resistance by progressive breast cancer. Here, we found that increased expression of pYBX1 was accompanied by acquired resistance to antiestrogens, fulvestrant and tamoxifen. Forced expression of YBX1/S102E, a constitutive phosphorylated form, resulted in acquired resistance to fulvestrant. Inversely, YBX1 silencing specifically overcame antiestrogen resistance. Furthermore, treatment with everolimus, an mTORC1 inhibitor, or TAS0612, a novel multikinase inhibitor of AKT, p70S6K, and p90RSK, suppressed YBX1 phosphorylation and overcame antiestrogen resistance in vitro and in vivo IHC analysis revealed that expression of pYBX1 and YBX1 was augmented in patients who experienced recurrence during treatment with adjuvant endocrine therapies. Furthermore, pYBX1 was highly expressed in patients with triple-negative breast cancer compared with other subtypes. TAS0612 also demonstrated antitumor effect against triple-negative breast cancer in vivo Taken together, our findings suggest that pYBX1 represents a potential therapeutic target for treatment of antiestrogen-resistant and progressive breast cancer.

Bidirectional Regulation between NDRG1 and GSK3ß Controls Tumor Growth and Is Targeted by Differentiation Inducing Factor-1 in Glioblastoma.

The development of potent and selective therapeutic approaches to glioblastoma (GBM), one of the most aggressive primary brain tumors, requires identification of molecular pathways that critically regulate the survival and proliferation of GBM. Previous studies have reported that deregulated expression of N-myc downstream regulated gene 1 (NDRG1) affects tumor growth and clinical outcomes of patients with various types of cancer including glioma. Here, we show that high level expression of NDRG1 in tumors significantly correlated with better prognosis of patients with GBM. Loss of NDRG1 in GBM cells upregulated GSK3ß levels and promoted cell proliferation, which was reversed by selective inhibitors of GSK3ß. In contrast, NDRG1 overexpression suppressed growth of GBM cells by decreasing GSK3ß levels via proteasomal degradation and by suppressing AKT and S6 cell growth signaling, as well as cell-cycle signaling pathways. Conversely, GSK3ß phosphorylated serine and threonine sites in the C-terminal domain of NDRG1 and limited the protein stability of NDRG1. Furthermore, treatment with differentiation inducing factor-1, a small molecule derived from Dictyostelium discoideum, enhanced NDRG1 expression, decreased GSK3ß expression, and exerted marked NDRG1-dependent antitumor effects in vitro and in vivo. Taken together, this study revealed a novel molecular mechanism by which NDRG1 inhibits GBM proliferation and progression. Our study thus identifies the NDRG1/GSK3ß signaling pathway as a key growth regulatory program in GBM, and suggests enhancing NDRG1 expression in GBM as a potent strategy toward the development of anti-GBM therapeutics. SIGNIFICANCE: This study identifies NDRG1 as a potent and endogenous suppressor of glioblastoma cell growth, suggesting the clinical benefits of NDRG1-targeted therapeutics against glioblastoma.

The augmented expression of the cytidine deaminase gene by 5-azacytidine predicts therapeutic efficacy in myelodysplastic syndromes.

5-Azacytidine (5AC), a hypomethylating agent, is clinically used for the treatment of patients with myelodysplastic syndromes (MDS). Cytidine deaminase (CDA) is a key enzyme in the detoxification of 5AC. We investigated whether the CDA expression could predict response to 5AC in MDS. Among leukemia-derived cell lines, MDS-L, an MDS-derived cell line with a relatively low CDA expression level, was found to be the most sensitive to 5AC. Combination with tetrahydrouridine, an inhibitor of CDA, synergistically potentiated the cytotoxic effect of 5AC. Treatment with 5AC markedly enhanced the expression level of CDA mRNA and showed demethylation at CpG sites in the 5'-flanking region of the CDA gene. We further compared the protein expression levels of CDA in matched clinical samples before and after treatment with 5AC in bone marrow cells from 8 MDS patients by an immunohistochemical analysis. The CDA expression level showed an approximately 2- to 3-fold increase after 5AC treatment in 3 of these cases, and these three patients with relatively higher CDA expression levels after 5AC treatment all showed better clinical responses to 5AC. In contrast, the 5 remaining patients, whose CDA expression showed no augmentation, observed no clinical benefit. Taken together, the optimized determination of the CDA expression levels before and after 5AC treatment, and the methylation status at CpG sites of 5'-flanking region of the CDA gene, may contribute to the development of precise 5AC therapy for MDS.

Oncogenic Y-box binding protein-1 as an effective therapeutic target in drug-resistant cancer.

Y-box binding protein-1 (YBX1), a multifunctional oncoprotein containing an evolutionarily conserved cold shock domain, dysregulates a wide range of genes involved in cell proliferation and survival, drug resistance, and chromatin destabilization by cancer. Expression of a multidrug resistance-associated ATP binding cassette transporter gene, ABCB1, as well as growth factor receptor genes, EGFR and HER2/ErbB2, was initially discovered to be transcriptionally activated by YBX1 in cancer cells. Expression of other drug resistance-related genes, MVP/LRP, TOP2A, CD44, CD49f, BCL2, MYC, and androgen receptor (AR), is also transcriptionally activated by YBX1, consistently indicating that YBX1 is involved in tumor drug resistance. Furthermore, there is strong evidence to support that nuclear localization and/or overexpression of YBX1 can predict poor outcomes in patients with more than 20 different tumor types. YBX1 is phosphorylated by kinases, including AKT, p70S6K, and p90RSK, and translocated into the nucleus to promote the transcription of resistance- and malignancy-related genes. Phosphorylated YBX1, therefore, plays a crucial role as a potent transcription factor in cancer. Herein, a novel anticancer therapeutic strategy is presented by targeting activated YBX1 to overcome drug resistance and malignant progression.

Y-box binding protein YBX1 and its correlated genes as biomarkers for poor outcomes in patients with breast cancer.

The enhanced expression of the Y-box binding protein YBX1 is consistently correlated with poor outcomes or reduced survival of breast cancer patients. However, the mechanism underlying the association between increased YBX1 expression and poor outcomes has yet to be revealed. We searched a database for the top 500 genes that are positively or negatively correlated with YBX1 and with ESR1 in breast cancer patients. We further examined the association between YBX1-correlated genes and breast cancer outcomes in patients at Kyushu University Hospital. More than 60% of genes that are positively correlated with YBX1 are also negatively correlated with ESR1. The enhanced expression levels of the top 20 positively correlated genes mostly predict negative outcomes, while the enhanced expression levels of the top 20 negatively correlated genes mostly predict positive outcomes. Furthermore, in breast cancer patients at Kyushu University Hospital, the expression levels of YBX1 and YBX1-positively correlated genes were significantly higher and the expression levels of genes negatively correlated with YBX1 were significantly lower in patients who relapsed after their primary surgery than in those who did not relapse. The expression of YBX1 together with the expression of its positively or negatively correlated genes may help to predict outcomes as well as resistance to endocrine therapies in breast cancer patients. Determining the expression of YBX1 and its closely correlated genes will contribute to the development of precision therapeutics for breast cancer.

The activation of SRC family kinases and focal adhesion kinase with the loss of the amplified, mutated EGFR gene contributes to the resistance to afatinib, erlotinib and osimertinib in human lung cancer cells.

Second- and third-generation inhibitors of epidermal growth factor receptor (EGFR) tyrosine kinase activity (EGFR-TKIs) are improving the treatment of patients with non-small cell lung cancer. Here we established two sublines (BR1-8 and BR2-3) resistant to a second-generation inhibitor, afatinib, from the human lung cancer cell line HCC827 that harbors a mutation that activates the tyrosine kinase activity of EGFR. These afatinib-resistant sublines were resistant to first-generation EGFR-TKIs, gefitinib and erlotinib, and a third-generation EGFR-TKI, osimertinib. These resistant sublines showed markedly reduced levels of multiple EGFR family proteins, including the activated mutant EGFR, and complete loss of EGFR amplification as compared with their parental HCC827 cells harboring amplification of EGFR gene. Treatment with the multikinase inhibitor dasatinib or transfection with a SRC small interfering RNA inhibited cell survival and AKT phosphorylation in drug-resistant sublines to a greater extent compared with HCC827 cells. Further, the migration of drug-resistant cells was greater compared with that of HCC827 cells and was inhibited by dasatinib or an FAK inhibitor. These findings indicate that compensatory activation of SRC family kinases (SFKs) and FAK supports the survival and migration of afatinib-resistant cells when the expression of multiple EGFR family proteins was mostly abrogated. Combinations of potent drugs that target SFKs and FAK may overcome the resistance of lung cancer cells to second-generation TKIs.

Breast Cancer Resistance to Antiestrogens Is Enhanced by Increased ER Degradation and ERBB2 Expression.

Endocrine therapies effectively improve the outcomes of patients with estrogen receptor (ER)-positive breast cancer. However, the emergence of drug-resistant tumors creates a core clinical challenge. In breast cancer cells rendered resistant to the antiestrogen fulvestrant, we defined causative mechanistic roles for the transcription factor YBX1 and the levels of ER and the ERBB2 receptor. Enforced expression of YBX1 in parental cells conferred resistance against tamoxifen and fulvestrant in vitro and in vivo Furthermore, YBX1 overexpression was associated with decreased and increased levels of ER and ERBB2 expression, respectively. In antiestrogen-resistant cells, increased YBX1 phosphorylation was associated with a 4-fold higher degradation rate of ER. Notably, YBX1 bound the ER, leading to its accelerated proteasomal degradation, and induced the transcriptional activation of ERBB2. In parallel fashion, tamoxifen treatment also augmented YBX1 binding to the ERBB2 promoter to induce increased ERBB2 expression. Together, these findings define a mechanism of drug resistance through which YBX1 contributes to antiestrogen bypass in breast cancer cells. Cancer Res; 77(2); 545-56. ©2016 AACR.

Phosphorylation of mTOR Ser2481 is a key target limiting the efficacy of rapalogs for treating hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Although recent studies facilitate the identification of crucial genes and relevant regulatory pathways, therapeutic approaches against advanced HCC are insufficiently effective. Therefore, we aimed here to develop potent therapeutics to provide a reliable biomarker for the therapeutic efficacy in patients with HCC. To this end, we first compared the cytotoxic effects of various anti-cancer drugs between well differentiated (HAK-1A) and poorly differentiated (HAK-1B) cell lines established from a single HCC tumor. Of various drug screened, HAK-1B cells were more sensitive by a factor of 2,000 to the mTORC1 inhibitors (rapalogs), rapamycin and everolimus, than HAK-1A cells. Although rapalogs inhibited phosphorylation of mTOR Ser2448 in HAK-1A and HAK-1B cells, phosphorylation of mTOR Ser2481 was specifically inhibited only in HAK-1B cells. Silencing of Raptor induced apoptosis and inhibited the growth of only HAK-1B cells. Further, three other cell lines established independently from the tumors of three patients with HCC were also approximately 2,000-fold times more sensitive to rapamycin, which correlated closely with the inhibition of mTOR Ser2481 phosphorylation by rapamycin. Treatment with everolimus markedly inhibited the growth of tumors induced by poorly differentiated HAK-1B and KYN-2 cells and phosphorylation of mTOR Ser2481 in vivo. To our knowledge, this is the first study showing that the phosphorylation of mTOR Ser2481 is selectively inhibited by rapalogs in mTORC1-addicted HCC cells and may be a potential reliable biomarker for the therapeutic efficacy of rapalogs for treating HCC patients.

Nuclear Y-Box-binding Protein-1 Expression Predicts Poor Clinical Outcome in Stage III Colorectal Cancer.

BACKGROUND/AIM: Y-Box-binding protein-1 (YB-1), a DNA/RNA-binding protein, is an important oncogenic transcription and translation factor. We aimed to evaluate the relationships between nuclear YB-1 expression, epidermal growth factor receptor (EGFR) status, and poor clinical outcomes in patients with colorectal cancer (CRC). MATERIALS AND METHODS: Nuclear YB-1 expression was immunohistochemically analyzed in CRC tissues obtained from 124 patients who underwent curative resection between 2005 and 2008. Correlations between nuclear YB-1 expression, various clinicopathological characteristics, EGFR status, and prognostic factors were evaluated. RESULTS: High-grade nuclear YB-1 expression was detected in 62.9% of cases and was found to be an independent predictor of poorer overall survival (p<0.001) and relapse-free survival (p<0.001). A trend was also observed towards a positive correlation between nuclear YB-1 expression and EGFR status (p=0.051). CONCLUSION: Nuclear YB-1 expression is a useful prognostic biomarker that correlates with EGFR status in patients with CRC.

Overcoming drug resistance to receptor tyrosine kinase inhibitors: Learning from lung cancer.

There are various receptor tyrosine kinase (TK)-targeted drugs that are currently used in the treatment of patients with non-small cell lung cancer (NSCLC). Among them, the epidermal growth factor receptor (EGFR) TK inhibitors (TKIs) are the most extensively studied. Receptor TKIs including EGFR TKIs have shown dramatic therapeutic efficacies in malignant tumors, which harbor activating mutations in the EGFR gene. However, within 1 or 2years after treatment, patients harboring these mutations often develop resistance to TKI therapy. This review article is aimed at drawing attention to the fact that we must first understand how receptor TKI resistance is acquired to develop strategies for overcoming resistance to TKIs. Furthermore, an insight into the specific molecules or signaling pathways that mediate resistance is a key factor for understanding and overcoming acquired drug resistance. Finally, we present our views on the continuing battle against "drug resistance," and provide further guidelines and strategies on how to minimize the development of drug-resistant tumors.

Impaired differentiation of macrophage lineage cells attenuates bone remodeling and inflammatory angiogenesis in Ndrg1 deficient mice.

N-myc downstream regulated gene 1 (NDRG1) is a responsible gene for a hereditary motor and sensory neuropathy-Lom (Charcot-Marie-Tooth disease type 4D). This is the first study aiming to assess the contribution of NDRG1 to differentiation of macrophage lineage cells, which has important implications for bone remodeling and inflammatory angiogenesis. Ndrg1 knockout (KO) mice exhibited abnormal curvature of the spine, high trabecular bone mass, and reduced number of osteoclasts. We observed that serum levels of macrophage colony-stimulating factor (M-CSF) and macrophage-related cytokines were markedly decreased in KO mice. Differentiation of bone marrow (BM) cells into osteoclasts, M1/M2-type macrophages and dendritic cells was all impaired. Furthermore, KO mice also showed reduced tumor growth and angiogenesis by cancer cells, accompanied by decreased infiltration of tumor-associated macrophages. The transfer of BM-derived macrophages from KO mice into BM-eradicated wild type (WT) mice induced much less tumor angiogenesis than observed in WT mice. Angiogenesis in corneas in response to inflammatory stimuli was also suppressed with decreased infiltration of macrophages. Taken together, these results indicate that NDRG1 deficiency attenuates the differentiation of macrophage lineage cells, suppressing bone remodeling and inflammatory angiogenesis. This study strongly suggests the crucial role of NDRG1 in differentiation process for macrophages.

CpG hypermethylation contributes to decreased expression of PTEN during acquired resistance to gefitinib in human lung cancer cell lines.

OBJECTIVES: We have previously reported that decreased expression of PTEN in lung cancer PC9 cells harboring an EGFR-activating mutation (del E746-A750) results in acquisition of resistance to EGFR-TKIs, gefitinib and erlotinib, accompanied by enhanced phosphorylation of Akt and decreased nuclear translocation of a transcription factor EGR-1 [8]. In the present study, PTEN promoter methylation accounted for the decreased expression of PTEN in our gefitinib-resistant mutant. MATERIAL AND METHODS: DNA methylation status of the PTEN promoter in PC9 and gefitinib-resistant cells were examined using methylation-specific PCR. The effect of DNA methylation on PTEN expression was evaluated by treatment of lung cancer cell lines with 5-aza-2'-deoxycytidine (5AZA-CdR). RESULTS: We observed the characteristics of two gefitinib-resistant sublines, GEF1-1 and GEF2-1, derived from PC9 as follows. (1) PTEN overexpression suppressed AKT phosphorylation and restored the sensitivity to gefitinib and erlotinib in GEF1-1 cells. (2) EGR-1 siRNA mediated knockdown suppressed the expression of cyclin D1 and ICAM-1 genes but not of PTEN gene in PC9 cells. (3) Transfection of EGR-1 cDNA into a drug-resistant subline induced the expression of cyclin D1 and ICAM-1 but not of PTEN. (4) Treatment with 5AZA-CdR induced the expression of PTEN in resistant sublines but not in the parental line PC9. (5) A CpG site near the translational start point of the 5'-regulatory region was methylated in GEF1-1 and GEF2-1 but not in PC9. CONCLUSION: Our results strongly suggest that CpG hypermethylation of the PTEN gene contributes to the decreased expression of PTEN during acquired resistance to gefitinib or erlotinib.

FGFR1 activation is an escape mechanism in human lung cancer cells resistant to afatinib, a pan-EGFR family kinase inhibitor.

Most NSCLC patients with EGFR mutations benefit from treatment with EGFR-TKIs, but the clinical efficacy of EGFR-TKIs is limited by the appearance of drug resistance. Multiple kinase inhibitors of EGFR family proteins such as afatinib have been newly developed to overcome such drug resistance. We established afatinib-resistant cell lines after chronic exposure of activating EGFR mutation-positive PC9 cells to afatinib. Afatinib-resistant cells showed following specific characteristics as compared to PC9: [1] Expression of EGFR family proteins and their phosphorylated molecules was markedly downregulated by selection of afatinib resistance; [2] Expression of FGFR1 and its ligand FGF2 was alternatively upregulated; [3] Treatment with anti-FGF2 neutralizing antibody blocked enhanced phosphorylation of FGFR in resistant clone; [4] Both resistant clones showed collateral sensitivity to PD173074, a small-molecule FGFR-TKIs, and treatment with either PD173074 or FGFR siRNA exacerbated suppression of both afatinib-resistant Akt and Erk phosphorylation when combined with afatinib; [5] Expression of twist was markedly augmented in resistant sublines, and twist knockdown specifically suppressed FGFR expression and cell survival. Together, enhanced expression of FGFR1 and FGF2 thus plays as an escape mechanism for cell survival of afatinib-resistant cancer cells, that may compensate the loss of EGFR-driven signaling pathway.

Chemical Composition of the Essential Oil of Mastic Gum and their Antibacterial Activity Against Drug-Resistant Helicobacter pylori.

ABSTRACT: Mastic gum is derived from the tree named Pistacia lentiscus that is grown only in Island Hios of Greek. Since Mastic was first reported to kill Helicobacter pylori (H. pylori) in 1998, there has been no further study to elucidate which component of mastic specifically shows the antimicrobial activity against H. pylori. In this study, we examined which component of mastic gum was responsible for anti-H. pylori activity. We prepared the essential oil of mastic gum and identified 20 constituents by GC-MS analysis. Ten standard components were assayed for anti-H. pylori activity, and it clarified that α-terpineol and (E)-methyl isoeugenol showed the anti-H. pylori activity against four different H. pylori strains that were established from patients with gastritis, gastric ulcer and gastric cancer. These components could be useful to overcome the drug-resistance H. pylori growth in stomach.

Tumor-derived interleukin-1 promotes lymphangiogenesis and lymph node metastasis through M2-type macrophages.

Tumors formed by a highly metastatic human lung cancer cell line are characterized by activated signaling via vascular endothelial growth factor (VEGF)-C through its receptor (VEGFR-3) and aggressive lymph node metastasis. In this study, we examined how these highly metastatic cancers acquired aggressive lymph node metastasis. Compared with their lower metastatic counterparts, the highly metastatic tumors formed by this cell line expressed higher amounts of interleukin (IL)-1α, with similarly augmented expression of IL-1α and IL-1ß by tumor stromal cells and of VEGF-A and VEGF-C by tumor-associated macrophages. These tumor-associated macrophages were mainly of the M2 type. Administration of a macrophage-targeting drug suppressed the production of these potent angiogenic and lymphangiogenic factors, resulting in decreased tumor growth, angiogenesis, lymphangiogenesis, and lymph node metastasis. In Matrigel plug assays, the highly metastatic cells formed tumors that were extensively infiltrated by M2-type macrophages and exhibited enhanced angiogenesis and lymphangiogenesis. All of these responses were suppressed by the IL-1 receptor (IL-1R) antagonist anakinra. Thus, the IL-1α-driven inflammatory activation of angiogenesis and lymphangiogenesis seems to provide a highly metastatic tumor microenvironment favorable for lymph node metastasis through cross-talk with macrophages. Accordingly, the IL-1R/M2-type macrophage axis may be a good therapeutic target for patients with this form of lung cancer.