Supernatants Of Cell Lines Research Articles

Classical Hodgkin lymphoma cells may promote an IL-17-enriched microenvironment

In classical Hodgkin lymphoma (cHL), the significance of the interplay between Hodgkin and Reed–Sternberg cells (HRS) and reactive T cells remains poorly defined. By immunohistochemistry on bioptic cHL specimens, we found that HRS and surrounding T lymphocytes stained positive for IL-17 in 40% of cases. IL-17 was detectable in a similar proportion of patients’ sera and correlated with disease burden. Supernatants of KM-H2 and HDLM-2 cHL cell lines guided preferential chemotaxis of CCR6+ T lymphocytes. Coculture of cHL cell lines with PBMC promoted the enrichment of Th17 lymphocytes and Foxp3+/IL-17+ cells, whereas T regulatory cells slightly decreased. Soluble CD30 downmodulated membrane CD30 expression on T cells and contributed to their polarization shift by stimulating IL-17 production and reducing IFN-γ synthesis. Thus, HRS and a number of reactive CD4+ T cells, attracted by tumor-secreted chemokines, produce an IL-17 tumor-shaped inflammatory milieu in a cHL subset.

Tumor-derived exosomes promote carcinogenesis of murine oral squamous cell carcinoma.

Circulating tumor-derived exosomes (TEX) interact with a variety of cells in cancer-bearing hosts, leading to cellular reprogramming which promotes disease progression. To study TEX effects on the development of solid tumors, immunosuppressive exosomes carrying PD-L1 and FasL were isolated from supernatants of murine or human HNSCC cell lines. TEX were delivered (IV) to immunocompetent C57BL/6 mice bearing premalignant oral/esophageal lesions induced by the carcinogen, 4-nitroquinoline 1-oxide (4NQO). Progression of the premalignant oropharyngeal lesions to malignant tumors was monitored. A single TEX injection increased the number of developing tumors (6.2 versus 3.2 in control mice injected with phosphate-buffered saline; P < 0.0002) and overall tumor burden per mouse (P < 0.037). The numbers of CD4+ and CD8+ T lymphocytes infiltrating the developing tumors were coordinately reduced (P < 0.01) in mice injected with SCCVII-derived TEX relative to controls. Notably, TEX isolated from mouse or human tumors had similar effects on tumor development and immune cells. A single IV injection of TEX was sufficient to condition mice harboring premalignant OSCC lesions for accelerated tumor progression in concert with reduced immune cell migration to the tumor.

Unique Protein Profiles of Extracellular Vesicles as Diagnostic Biomarkers for Early and Advanced Non-Small Cell Lung Cancer.

Extracellular vesicles (EVs) mediate intercellular communication via transferring proteins and other biological molecules and have been recently investigated as biomarkers of disease. Sensitive and specific biomarkers are required for lung cancer diagnosis and prognosis. The present study screens for abnormal EV proteins in non-small cell lung cancer (NSCLC) using a quantitative proteomics strategy involving LC-MS/MS to identify ideal biomarkers for NSCLC diagnosis. EVs are enriched from the sera of early and advanced NSCLC patients and healthy controls and from cell culture supernatants of lung adenocarcinoma and bronchial epithelial cell lines. In the sera and supernatants, 279 and 632 differentially expressed proteins, respectively, are associated with signaling pathways including extracellular membrane-receptor interaction, focal adhesion, and regulation of the actin cytoskeleton. Thirty-two EV proteins are identified at the intersection of differentially expressed proteins between the NSCLC groups and cell lines. Based on bioinformatics analysis, in silico immunohistochemical, and PRM verification, fibronectin is selected for following in vitro studies and validation with an independent cohort. Fibronectin on EVs is estimated to perform well in the diagnosis of NSCLC patients based on AUC, showing great potential for clinical use and demonstrating the efficacy of this method for EV-associated biomarker screening.

Epstein-Barr virus-positive pyothorax-associated lymphoma expresses CCL17 and CCL22 chemokines that attract CCR4-expressing regulatory T cells.

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphomas associated with chronic inflammation (DLBCL-CI) develop in patients with chronic inflammation but without any predisposing immunodeficiency. Given the expression of the EBV latent genes, DLBCL-CI should have mechanisms for evasion of host antitumor immunity. EBV-positive pyothorax-associated lymphoma (PAL) is a prototype of DLBCL-CI and may provide a valuable model for the study of immune evasion by DLBCL-CI. This study demonstrates that PAL cell lines express and secrete CCL17 and/or CCL22 chemokines, the ligands of C-C motif chemokine receptor 4 (CCR4), in contrast to EBV-negative DLBCL cell lines. Accordingly, culture supernatants of PAL cell lines efficiently attracted CCR4-positive regulatory T (Treg) cells in human peripheral blood mononuclear cells. PAL cells injected into mice also attracted CCR4-expressing Treg cells. Furthermore, this study confirmed that CCR4-expressing Treg cells were abundantly present in primary PAL tissues. Collectively, these findings provide new insight into the mechanisms of immune evasion by PAL, and further studies are warranted on whether such mechanisms eventually lead to the development of DLBCL-CI.

(354) Repurposing Druggable Targets for the Treatment of Cancer Pain: A Translational Approach

Cancer cells secrete pro-nociceptive mediators into the microenvironment that sensitize sensory neurons and cause pain. We sought to identify protein encoding genes that drive nociception. We used a preclinical mouse model, transcriptomic analysis, and a proteomic literature review to undertake this work. Cancer cell line supernatant was assigned a phenotype based on evoked nociceptive behavior in a cancer pain mouse model. Mice received 50μl injections of supernatant in the tongue for 3 days followed by orofacial behavior assessment with a dolognawmeter 1 hour after the third injection. Data from the NCBI Gene Expression Omnibus was used to performdifferential gene expression and pathway analysis. We identified proteins potentially responsible for nociception using a literature review of the nociceptive cell lines. Mediator targets produced by these analyses were validated with the cancer pain mouse model. We identified 4 nociceptive and 4 non-nociceptive cell lines. We subsequently identified 1760 differentially expressed genes (DEG) and 14 significantly perturbed pathways by comparing the nociceptive and non-nociceptive cell lines. Thirty of 1760 DEG were reported in the literature to yield over-expressed proteins secreted or anchored to the plasma membrane in at least one of the nociceptive cell lines tested. For these 30 DEG, epidermal growth factor receptor (EGFR) was the most commonly cited druggable target (Drug–Gene Product Interaction Database). To determine if EGFR signaling is involved in cancer supernatant-induced nociception, we administered either EGFR antagonist, Cetuximab, or saline followed by nociceptive cell line supernatant injected into the mouse tongue. Mice that received saline exhibited significantly longer gnaw-time following injection of cancer supernatant (48.8±4.5%) compared to mice that received Cetuximab (13.8±11.8%). DEG and their secreted protein products may serve as therapeutic targets for cancer pain and warrant further evaluation.

Optimization of cell culture conditions for exosome isolation using mini-size exclusion chromatography (mini-SEC)

Extracellular vesicles (EVs) are emerging as a major intercellular communication system engaged in a variety of physiological and pathophysiological processes. Tumor-derived exosomes (TEX) are a subset of EVs of special interest as potential cancer biomarkers. Supernatants of tumor cell lines are widely used as the source of pure TEX for molecular/genetic studies. To optimize TEX isolation and characterization for these studies, we evaluated culture conditions for different tumor cell lines and used mini size exclusion chromatography (mini-SEC) for TEX isolation. Each tumor cell line showed unique culture requirements that determined the recovery, purity and total yield of TEX. Culture conditions for optimal TEX purity and recovery by mini-SEC could be modified by altering the media composition and numbers of seeded cells. TEX recovered from mini-SEC fraction #4 under optimized conditions were biologically active, were sized from 30 to 150 nm in diameter, had a typical vesicular morphology and carried endocytic markers. The most critical requirement for reproducible exosome recovery was re-seeding of tumor cells in numbers adjusted to reflect the optimized culture conditions for each tumor cell line. This study provides insights into a cell culture technique, which can be optimized for exosome production by various human or mouse tumor cell lines for isolation by mini-SEC.

S-Geranylgeranyl-L-glutathione is a ligand for human B cell-confinement receptor P2RY8.

Germinal centers (GCs) are important sites for antibody diversification and affinity maturation and are also a common origin of B-cell malignancies. Although made up of motile cells, GCs are tightly confined within B-cell follicles. The cues promoting GC B-cell confinement are incompletely understood. P2RY8 is a Gα13-coupled receptor that mediates migration inhibition and growth regulation of B cells in lymphoid tissues4,6. P2RY8 is frequently mutated in GC-derived diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma (BL)1–5, and the ligand for this receptor has been undefined. In a search for P2RY8 ligands, we found P2RY8 bioactivity in bile and in culture supernatants of several cell lines. Using a seven-step biochemical fractionation procedure and a drop-out mass spectrometry approach, we identified a previously undescribed biomolecule, S-geranylgeranyl-L-glutathione (Ggg) as a potent P2RY8 ligand. Ggg was detectable in lymphoid tissues in the nanomolar range. Ggg inhibited chemokine-mediated migration of human GC B cells and follicular helper T cells and antagonized induction of pAkt in GC B cells. We found that gamma-glutamyltransferase-5 (Ggt5) metabolized Ggg to a form inactive on the receptor. Ggt5 was highly expressed by follicular dendritic cells (FDCs). Over-expression of this enzyme disrupted the ability of P2RY8 to promote B-cell confinement to GCs, indicating that it establishes a Ggg gradient in lymphoid tissues. This work defines Ggg as an intercellular signaling molecule involved in organizing and controlling GC responses. As well as DLBCL and BL the P2RY8 locus is modified in several other cancers and we speculate that Ggg has organizing and growth regulatory activities in multiple human tissues.

Identification of programmed cell death 1 and its ligand in the testicular tissue of mice.

This study aims to determine the expression and localization of programmed cell death 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) in the testes of mice at different developmental stages. By means of RT-qPCR, Western blot and immunofluorescence, the expression and localization of PD-1 and PD-L1 were detected in the testicular tissues of mice at different postnatal times: P7, P14, P21, P28, P35, and adulthood. Meanwhile, the level of soluble PD-L1 (sPD-L1) was evaluated by ELISA in the testicular interstitial fluid (IF) of the adult mice, culture supernatants of TM4 cell lines (Sertoli cells lines), and primary Sertoli cells at P14. Pd-1 mRNA levels were unexpectedly low. From P7 to P21, there was limited PD-1 protein detected while PD-1 was evident at P28 and afterward at significantly higher levels than at P14 and P21 (P<0.05). Despite being found in the interstitial area at P7, P14, and P21, PD-1 was also detected in the germ cells of the seminiferous tubules after P28. Pd-l1 mRNA exhibited age-related changes, peaking at P21, while PD-L1 protein was constitutively expressed at any stage, specifically localized in the nucleus of Sertoli cells. Moreover, the level of sPD-L1 in IF was significantly higher than that in the culture supernatants of both TM4 and primary Sertoli cells at P14. PD-1 and PD-L1 were present in the testicular tissue of adult mice. The expression and localization of PD-1 fluctuated with age, and PD-1 was mainly localized to advanced germ cells, suggesting that it may play a role in spermiogenesis. PD-L1 was constitutively expressed in the nucleus of Sertoli cells, which could secrete sPD-L1 into the testicular interstitial space and thus may be involved in testicular immune privilege.

Myeloma Cells Have the Ability to Suppress Th1-Inducing Capacity but Enhance Th2-Mediated Response of Dendritic Cells By Producing Factors Other Than Soluble SLAMF7

Background: Lenalidomide (LEN), as a backbone drug for multiple myeloma (MM), has both direct tumoricidal and immunomodulatory effects in MM. LEN displays immunopotentiating activity, including augmentation of T and natural killer cell function and to induce selective reduction of regulatory T cells. Thus, the immune-based cancer treatments are currently important in MM therapy. Since myeloma cells together with immune cells are immersed in the pathogenic micro-environment, understanding the influence of micro-environment against myeloma cells and immune system may lead to the development of novel treatment strategies for MM. Series of analyses have clarified a functional plasticity of dendritic cells (DCs) to induce Th1 or Th2 response and DCs are pivotal in orchestrating both innate and acquire immune responses also in the anti-tumor immunity. Here, we focused on the effects of myeloma environment to modulate the human myeloid DCs (mDCs), which are the major regulators to induce Th1 or Th2 responses. Soluble form of SLAMF7 (sSLAMF7) is a pivotal environmental component of MM and functions as a self-ligand of myeloma cells. sSLAMF7 has been detected in the serum of patients with MM at higher levels than healthy individuals and therefore may presumably play some roles in pathophysiological condition of MM. To evaluate the functions of soluble factors/components derived from myeloma cells, we analyzed whether supernatants of myeloma cell lines could modulate mDC functions. Methods: Using cell sorting, blood human CD11+ mDCs were isolated from healthy adult volunteers. The DC functions were analyzed after culture for 24 h with supernatant of myeloma cell lines, NCI-H929 (H929) or MM.1R. This study was approved by the Institutional Review Board of Kansai Medical University.Results: We here found that both supernatants of myeloma cell lines, H929 and MM.1R did not affect CD86 expression on mDCs in response to toll-like receptor (TLR)-ligand (R848), but upregulated their CD86 expression in response to Th2-inducing cytokine, thymic stromal lymphopoietin (TSLP). Of note, the supernatants inhibited mDC-derived IL-12 production in response to R848 (p < 0.05: H929; 25-30% of cont. and MM1.R; less than 50 % of cont.), while in response to TSLP, dose-dependently enhanced the Th2-recruiting chemokine CCL17/TARC production (p < 0.05: H929; 130- 210 % of cont. and MM1.R; 120-185 % of cont.), which functions as chemoattractant for memory Th2 cells and contribute to promote humoral response. In addition, we revealed that these capacities were further enhanced by the addition of LEN at clinical in vivo plasma concentration of 1 µM. Thus, MM micro-environment could have the potential to shift DC-mediated response from Th1 to Th2. To clarify whether sSLAMF7 in the supernatant of myeloma cell lines play a role in the Th1/Th2-modulating effect, we calculated the sSLAMF7 concentration in the supernatants and analyzed an inhibitory effect of elotuzumab for the DC function induced by the supernatants. sSLAMF7 could not be detected at all in the supernatants of both myeloma cell lines, even in any concentration of cells. Furthermore, addition of 30 to 100 ug/ml (clinical trough serum concentration) elotuzumab into the culture of mDCs and the supernatants did not affect the CD86 expression and IL-12/CCL17 production. Hence, factors other than sSLAMF7 from myeloma cells can trigger DCs to suppress Th1 response and to promote Th2 response.Conclusion: Our data suggest that the MM micro-environment, while suppress the Th1-inducing capacity, rather lead to enhance Th2 response at DC phase. As sSLAMF7 is detected in the serum of patients with MM but not in the supernatants of MM cell lines in the experimental setting, there is a limitation that our data does not consider the action of sSLAMF7. However, the present result provides an important clue for understanding the biological basis for the MM micro-environment against host immune defense at onset. DisclosuresIto:Bristol-Myers Squibb: Honoraria, Research Funding; Takeda: Honoraria; Novartis Pharma: Honoraria; Pfizer: Honoraria; Mundipharma: Honoraria; Celgene: Honoraria.

Thymic stromal lymphopoietin in human pancreatic ductal adenocarcinoma: expression and prognostic significance.

Thymic stromal lymphopoietin (TSLP) has emerged as an important, but contradictory, player conditioning tumor growth. In certain contexts, by driving T helper (h) 2 responses via tumor-associated OX40 Ligand (OX40L)+ dendritic cells (DCs), TSLP may play a pro-tumorigenic role. The study elucidates the importance of TSPL in pancreatic ductal adenocarcinoma (PDAC), by analyzing: i) TSLP levels in PDAC cell-line supernatants and plasma from patients with locally-advanced/metastatic PDAC, pre- and post-treatment with different chemotherapeutic protocols, in comparison with healthy donors; ii) TSLP and OX40L expression in PDAC and normal pancreatic tissues, by immunohistochemistry; iii) OX40L expression on ex vivo-generated normal DCs in the presence of tumor-derived TSLP, by flow cytometry; iv) clinical relevance in terms of diagnostic and prognostic value and influence on treatment modality and response.Some PDAC cell lines, such as BxPC-3, expressed both TSLP mRNA and protein. Normal DCs, generated ex vivo in the presence of TSLP-rich-cell supernatants, displayed increased expression of OX40L, reduced by the addition of a neutralizing anti-TSLP polyclonal antibody. OX40L+ cells were detected in pancreatic tumor inflammatory infiltrates. Abnormally elevated TSLP levels were detected in situ in tumor cells and, systemically, in locally-advanced/metastatic PDAC patients. Of the chemotherapeutic protocols applied, gemcitabine plus oxaliplatin (GEMOX) significantly increased circulating TSLP levels. Elevated plasma TSLP concentration was associated with shorter overall survival and increased risk of poor outcome. Plasma TSLP measurement successfully discriminated PDAC patients from healthy controls.These data show that TSLP secreted by pancreatic cancer cells may directly impact PDAC biology and patient outcome.

3076 - Mir-16 Regulates Crosstalk in NF-KB Inflammatory Signaling between Myeloma Cells and Bone Marrow Macrophages (MQ)

Multiple myeloma plasma cells (MM-PC) home to and dynamically interact with the bone marrow (BM) microenvironment (BM-ME). Of the different factors secreted by the BM-ME, NF-KB-induced cytokines including IL-6 play a central role in MM-PC survival and resistance to treatments. Extracellular vesicles (EV) are membrane-covered cell fragments released by all cell types, and recently they have been shown to play a pivotal role in creating a tumor supportive BM-ME. Here, we investigated whether MM derived EV can play a pivotal role in supporting monocyte to TAM differentiation that can be reversed by miR-16. Our in vitro data show that EV isolated from the supernatant of MM cell lines (MM-EV) can promote monocyte differentiation to CD163+ TAM. MQ differentiation was also observed when peripheral blood monocytes (PB-M) obtained from both MM and healthy donors were treated with EV isolated from the BM acellular fraction of MM patients (n = 4). Limited differentiation was instead observed when the acellular fraction was EV-depleted. Our data show that PB-M differentiation was partially reversed by the addition of an EV-miR-16 mimic. Our Ex vivo data showed that isolation of MQ from the BM of miR-16 knockout mice differentiated towards M2-TAM phenotype as marked by higher surface expression of Dectin-1 and CD206 compared to MQ isolated from the BM of Wild type B6 mice. We also found that miR-16 is dramatically down regulated when PB-M is induced by macrophage colony stimulating factor to differentiate to TAM, and it is also down regulated in primary BM-MQ as compared to PB-M of the same patients and to the BM-MQ of 3 age matched healthy donors. We learned that BM-MQ isolated from MM patients are the main source of NF-KB-induced cytokines including IL-6 and IL-10 under unstimulated conditions as well as IL-6, IL-8, IL-10, TNF-a and VEGF under Toll-like receptor stimulated conditions, as the MQ-depleted BM cellular fraction had significantly low levels. NF-KB decreases MM cells dependency on extrinsic growth factors, at the onset of the disease miR-16 downregulation in MM-PCs can support NF-kB intrinsic inflammatory activation and increase fitness of MM cells.

Abstract 5663: Proteomic analysis of exosomes isolated from ccRCC cell lines

Abstract Purposes of the study: Clear renal cell carcinoma (ccRCC) is one of the most lethal malignant tumors. Molecular targeted therapies have been used to improve outcomes for metastatic or advanced ccRCC. However, currently approved therapies have limited success and a cure remains elusive. Since ccRCC could be curable if diagnosed at the early stage, novel diagnostic approach is needed to identify circulating markers that may help diagnose early and evaluate prognosis. Exosomes are membrane vesicles with a diameter of 40-150 nm that are secreted by various types of cells including cancer cells. Exosomes contain a variety of molecular constituents of their origin such as proteins and nucleic acids. Over the years, exosome has been suggested to be a novel diagnostic marker. The purpose of this study is to find candidates of ccRCC markers in exosomes. Experimental procedures: Exosomes were collected from cell culture supernatant of RPTEC human renal proximal tubule epithelial cells and ccRCC cell lines (Caki-1, KMRC-1, and OS-RC-2) by ultracentrifugation. Isolation of exosome was confirmed by western blot analysis for CD9. Exosome fraction was analyzed by iTRAQ-based quantitative proteomics. Results: A total of 52 proteins were detected and 3 proteins were found to be upregulated by more than 1.2 fold in exosomes isolated from ccRCC cells compared with those from RPTEC cells. Twelve proteins were found to be downregulated by less than 0.8 fold in exosomes from ccRCC cells compared with those from RPTEC cells. The expression profiles of several proteins were verified by western blot analysis. Conclusions: While major challenges still remain, exosome studies in ccRCC could provide a wealth of information to find novel diagnostic and prognostic markers. Citation Format: Kosuke Mizutani, Kyojiro Kawakami, Yasunori Fujita, Kengo Horie, Masafumi Ito, Takashi Deguchi. Proteomic analysis of exosomes isolated from ccRCC cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5663.

Expression profile of human tissue kallikrein 15 provides preliminary insights into its roles in the prostate and testis

BackgroundHuman tissue kallikrein 15 (KLK15) is the latest member of the kallikrein-related peptidase family. Little is known about the pathophysiological roles of KLK15. Previous studies implied a role of KLK15 in prostate cancer. MethodsIn the present study, we examined KLK15 protein expression using a new immunoassay (ELISA) and immunohistochemistry (IHC). ResultsHighest KLK15 levels were detected in the testis and seminal fluid, whereas lower levels were observed in prostate and other tissues. Immunohistochemical analysis of testis suggests that KLK15 is strongly expressed in mature spermatids, but not in immature germ cells. KLK15 displayed predominantly nuclear localization in the basal cell layer of the prostatic epithelium. We also measured KLK15 in supernatants of various cell lines. Highest KLK15 levels were primarily detected in prostate cancer cell lines and KLK15 expression was hormone-independent, in contrast to KLK3. ConclusionsCollectively, our data provide insights into the localization and possible role of KLK15 in human physiology.

Exploring the potential of mucin 13 (MUC13) as a biomarker for carcinomas and other diseases.

Mucin 13 (MUC13) is a cell surface glycoprotein aberrantly expressed in a variety of epithelial carcinomas. Thus far, the role of MUC13 in various diseases remains elusive. To the best of our knowledge, this is the first study to examine the potential of MUC13 as a serum biomarker in a variety of carcinomas and other conditions. We developed a recombinant MUC13 protein, mouse monoclonal antibodies and enzyme immunoassay (ELISA) for MUC13. We used this assay to measure MUC13 levels in the supernatants of cancer cell lines and a large cohort of serum samples from healthy and diseased individuals. MUC13 is secreted from cancer cell lines, with highest levels found in ovarian cancer cell lines. MUC13 levels in human sera were significantly increased in patients with renal failure and 20%-30% of patients with ovarian, liver, lung and other cancers. MUC13 was also elevated in 70% of patients with active cutaneous melanoma, but not uveal melanoma. Furthermore, we identified significant MUC13 elevations in the serum of patients with vasculitis (ANCA-positive) autoantibodies, but not in those with inflammatory bowel disease. Serum MUC13 is frequently elevated not only in a variety of malignant cases but also in some benign pathologies, thus appearing to be a non-specific disease biomarker. Nonetheless, serum MUC13 is clearly highly elevated in some carcinoma patients, and its relationship with tumor progression in this context warrant further research. Future studies that examine the correlation between serum MUC13 levels to stage of cancer could elucidate prognostic potential.

Extracellular nicotinamide phosphoribosyltransferase (eNAMPT) is a novel marker for patients with BRAF-mutated metastatic melanoma

Metastatic melanoma carrying BRAF mutations represent a still unmet medical need as success of BRAF inhibitors is limited by development of resistance. Nicotinamide phosphoribosyltransferase (NAMPT) is a key enzyme in NAD biosynthesis. An extracellular form (eNAMPT) possesses cytokine-like functions and is up-regulated in inflammatory disorders, including cancer. Here we show that eNAMPT is actively released in culture supernatants of melanoma cell lines. Furthermore, cells that become resistant to BRAF inhibitors (BiR) show a significant increase of eNAMPT levels. Plasma from mice xenografted with BiR cell lines contain higher eNAMPT levels compared to tumor-free animals. Consistently, eNAMPT levels are elevated in 113 patients with BRAF-mutated metastatic melanoma compared to 50 with localized disease or to 38 healthy donors, showing a direct correlation with markers of tumor burden, such as LDH, or aggressive disease (such as PD-L1). eNAMPT concentrations decrease in response to therapy with BRAF/MEK inhibitors, but increase again at progression, as inferred from the serial analysis of 50 patients. Lastly, high eNAMPT levels correlate with a significantly shorter overall survival.Our findings suggest that eNAMPT is a novel marker of tumor burden and response to therapy in patients with metastatic melanoma carrying BRAF mutations.

Type VI collagen α1 chain polypeptide in non-triple helical form is an alternative gene product of COL6A1.

Expression of type IV collagen α1 chain in non-triple helical form, NTH α1(IV), is observed in cultured human cells, human placenta and rabbit tissues. Biological functions of NTH α1(IV) are most likely to be distinct from type IV collagen, since their biochemical characteristics are quite different. To explore the biological functions of NTH α1(IV), we prepared some anti-NTH α1(IV) antibodies. In the course of characterization of these antibodies, one antibody, #141, bound to a polypeptide of 140 kDa in size in addition to NTH α1(IV). In this study, we show evidence that the 140 kDa polypeptide is a novel non-triple helical polypeptide of type VI collagen α1 chain encoded by COL6A1, or NTH α1(VI). Expression of NTH α1(VI) is observed in supernatants of several human cancer cell lines, suggesting that the NTH α1(VI) might be involved in tumourigenesis. Reactivity with lectins indicates that sugar chains of NTH α1(VI) are different from those of the α1(VI) chain in triple helical form of type VI collagen, suggesting a synthetic mechanism and a mode of action of NTH α1(VI) is different from type VI collagen.

Significance of Lysyl oxidase‑like2 gene expression on the epithelial‑mesenchymal status of hepatocellular carcinoma.

In the present study, we investigated the role of lysyl oxidase‑like2(LOXL2), the correlation between LOXL2 and epithelial to mesenchymal transition(EMT) and the effects of using β‑aminopropionitrile(BAPN) to inhibit LOXL2 with the aim of reducing tumor progression in hepatocellular carcinoma(HCC). The expression level of LOXL2 was evaluated in HCC and adjacent non‑cancerous tissues using quantitative reverse transcription polymerase chain reaction and clinicopathological analyses. The effects of BAPN on cell proliferation, migration and invasion were investigated invitro. Additionally, LOXL2 expression was assessed in the culture supernatants of HCC cell lines. Our results revealed that LOXL2 expression was higher in HCC cell lines and tissues. There was a significant correlation between EMT status and LOXL2 levels(P=0.004). BAPN reduced migration and invasion in HCC cells. HCC patients with high levels of LOXL2 expression had relatively shorter disease‑free survival(P=0.009) and overall survival(P=0.035). The expression level of LOXL2 was similar between cell supernatants and HCC cell lines. A multivariate analysis demonstrated that portal vein invasion(P=0.015), venous invasion(P=0.026), serum AFP(α‑fetoprotein) levels(P=0.019) and LOXL2 expression(P=0.009) were independent prognostic factors. Our results indicated that a higher level of LOXL2 may contribute to tumor progression, indicating that LOXL2 has clinical value as a therapeutic target in HCC.

475 (PB-108) - The supernatant of high metastatic breast cancer cell lines can change the IL-17B and MMP1 expression of breast non-malignant cells

475 (PB-108) - The supernatant of high metastatic breast cancer cell lines can change the IL-17B and MMP1 expression of breast non-malignant cells

Cellular response to persistent foot-and-mouth disease virus infection is linked to specific types of alterations in the host cell transcriptome

Food-and-mouth disease virus (FMDV) is a highly contagious virus that seriously threatens the development of animal husbandry. Although persistent FMDV infection can dramatically worsen the situation, the mechanisms involved in persistent FMDV infection remain unclear. In the present study, we identified the presence of evolved cells in the persistently FMDV-infected cell line. These cells exhibited resistance to the parent FMDV and re-established persistent infection when infected with FMDV-Op (virus supernatant of persistent infection cell lines), emphasizing the decisive role of evolved host cells in the establishment of persistent FMDV infection. Using RNA-seq, we identified the gene expression profiles of these evolved host cells. In total, 4,686 genes were differentially expressed in evolved cells compared with normal cells, with these genes being involved in metabolic processes, cell cycle, and cellular protein catabolic processes. In addition, 1,229 alternative splicing events, especially skipped exon events, were induced in evolved cells. Moreover, evolved cells exhibited a stronger immune defensive response and weaker MAPK signal response than normal cells. This comprehensive transcriptome analysis of evolved host cells lays the foundation for further investigations of the molecular mechanisms of persistent FMDV infection and screening for genes resistant to FMDV infection.

Influence of tumor cell culture supernatants on macrophage functional polarization: in vitro models of macrophage-tumor environment interaction.

Macrophages are heterogeneous cells with extensive functional plasticity; they can change their functional profiles repeatedly in response to environmental changes anywhere between their extreme phenotypical programs (labeled as M1 and M2 polarization, respectively). In terms of antitumoral immune response, M1 macrophages are considered to be beneficial, while M2 macrophages supposedly promote tumor progression. Tumor-associated macrophages (TAMs) represent a major leukocyte population present in many tumors. Although many studies indicate that TAMs elicit several M2-associated protumoral functions, including promotion of angiogenesis, matrix remodeling and suppression of adaptive immunity, their role regarding tumor progression is still controversial. The aim of the present study was to develop an appropriate in vitro model to study the effect of tumor-secreted soluble factors on the functional phenotype of macrophages. THP-1 human monocytic line cells and peripheral blood mononuclear cells from healthy volunteers were used for macrophage differentiation; primary tumor cell culture supernatants or tumor cell line supernatants were employed along with various cytokines, growth factors and other stimuli to design different model variants and to better mimic the in vivo tumor microenvironment. The cytokine secretion patterns of these macrophages suggest that primary tumor cell culture supernatants are able to switch the macrophage phenotype or to induce functional polarization of macrophages toward a mixed M1/M2 phenotype. Conclusions. These data support the hypothesis that TAM behavior is modulated by the tumor microenvironment itself.