Search

Introduction Clinical studies have indicated a relationship between diabetic nephropathy (DN) and the incidence and prevalence of renal cell carcinoma (RCC). However, the mechanism linking diabetic nephropathy and renal cell carcinoma has not yet to be identified. Methods In this study, a total of 42 male Sprague Dawley (SD) rats were randomly assigned to a DN group (n=35) and a control group (n=7). All animals in the DN group were unilaterally nephrectomized and treated with streptozotocin with the development of blood glucose levels >16.7mmol/L and dominant proteinuria and were compared to controls without such changes. Histopathologic alterations in the kidneys were examined by HE staining and Ki-67 immunohistochemistry. Differentially expressed genes were identified and validated by RNA-seq and PCR. Results As the results, except for two rats that failed to develop the DN model and were excluded from the analysis, 33 rats in the DN group with overt signs of DN demonstrated significantly higher food and water intake, urine production, and urine protein and urinary protein/creatinine ratio than controls. Overall, 15.2% (n=5/33) of DN animals developed RCC while none tumors were observed in the control group (n=0/7). RNA-seq analysis in these animals indicated different TRPV5 gene expression and calcium pathway expression in DN animals with developing tumors, when compared with animals with no obvious tumors. In addition, DN animals diagnosed with RCC showed increased expression of GLUT2 and c-met, when compared to controls and DN animals without tumors. Discussion In conclusion, the disordered calcium metabolism, especially disturbed TRPV5 mediated Ca2+ signal, may have been related to the development of RCC in DN rats. Further studies related to the detailed mechanism are still needed.

A) CD133+ cytoplasmic B) AXL+ combined C) c-MYC+ nuclear, Background: CD133 and AXL have been described as cancer stem cell markers, and c-MYC as a key regulatory cellular mechanism in colorectal cancer (CRC). Aim: Evaluate the prognostic role of the biomarkers CD133, AXL and c-MYC and their association with clinicopathologic characteristics in colorectal adenocarcinomas and adenomas. Methods: A total of 156 patients with UICC stage I-IV adenocarcinomas (n=122) and adenomas (n=34) were analyzed. Tissue microarrays (TMA) from primary tumors and polyps for CD133, c-MYC and AXL expression were performed and analyzed for their significance with clinicopathologic characteristics. Results: Poorly differentiated adenocarcinomas and disease progression were independent risk factors for poor overall survival. The median overall survival time was 30 months. Positive CD133 expression (35.9% of all cases), particularly of right-sided CRCs (44.8% of the CD133+ cases), was negatively correlated with death in the univariate analysis, which did not reach significance in the multivariate analysis. c-MYC (15.4% of all cases) was predominantly expressed in advanced-stage patients with distant (non-pulmonary/non-hepatic) metastasis. AXL expression was found only occasionally, and predominantly dominated in adenomas, with less penetrance in high-grade dysplasia. Conclusions: CD133 expression was not associated with inferior overall survival in CRC. While AXL showed inconclusive results, c-MYC expression in primary CRCs was associated with distant metastasis.

SUMMARYSignal transducer and activator of transcription 3 (STAT3) is a key transcription factor implicated in the pathogenesis of kidney fibrosis. Although tubular Stat3 deletion in tubular epithelial cells is known to protect mice from kidney fibrosis, the exact function of STAT3 in stromal cells remains unknown. We utilized stromal-cell Stat3 knock-out (KO) mice, CRISPR and pharmacologic activators and inhibitors of STAT3 to investigate its function in pericyte-like cells. STAT3 is phosphorylated in tubular epithelial cells in acute kidney injury whereas its activation expanded to interstitial cells in chronic kidney disease in mice and humans. Stromal cell-specific deletion of Stat3 protects mice from folic acid- and aristolochic acid-induced kidney fibrosis. Mechanistically, STAT3 directly regulates the inflammatory pathway, differentiation of pericytes into myofibroblasts. Specifically, STAT3 activation leads to an increase in migration and profibrotic signaling in genome-edited pericyte-like cells, 10T1/2. Conversely, Stat3 KO or blocking STAT3 function inhibits detachment, spreading, migration, and profibrotic signaling. Furthermore, STAT3 binds to Collagen1a1 promoter of fibrotic mouse kidneys and in pericyte-like cells. Together, our study identifies a previously unknown function of STAT3 in stromal cells that promotes kidney fibrosis and may have therapeutic value in fibrotic kidney disease.Graphical Abstract

Background. Coronavirus disease 2019 (COVID-19) causes psychological distress and can have a negative impact on the general mental health and rehabilitation in affected patients under currently implemented isolation guidelines. Auricular point pressure (APP) as well-established technique in traditional Chinese medicine may help to relieve sleep disturbance and anxiety in COVID-19 patients. Methods. During the early phase of the epidemic/pandemic, patients were enrolled in this study (02/2020 until 03/2020 n = 84). They were strictly isolated on specific wards at the Hubei Provincial Hospital of Integrated Chinese and Western Medicine in Hubei. The retrospective cohort study design included two groups. Group A patients were treated with an auricular point pressure (APP) in addition to standard intensive care medicine while Group B participants (No-APP) received routine nursing measures alone. Treatment outcome was measured using the St. Mary’s Hospital Sleep Questionnaire (SMH) Score and the 7-Item Generalized Anxiety Disorder Scale (GAD-7). Both scores were measured in each patient at baseline and on the discharge day. Results. The SMH score and sleep status changed in APP patients at the end of the treatment period when compared with No-APP patients ( P < 0.01 ). APP-treated patients demonstrated lower GAD-7 scores than No-APP controls ( P < 0.01 ). Further, no significant differences in safety or adverse events between the APP and No-APP groups were observed. Conclusion. The results from our snapshot study during the early phase of the SARS-CoV-2 epidemic/pandemic suggest that auricular point pressure could be a simple and effective tool to relieve insomnia and situational anxiety in hospitalized patients suffering from COVID-19 and kept under disconcerting conditions of isolation.

Expression of CD133 and ABCB5 is associated with tumor aggressiveness, but evidence in papillary thyroid cancer (PTC) is lacking. We correlated CD133 and ABCB5 expression with pathological characteristics and factors of worse prognosis in PTC. Samples of 119 PTCs and 40 controls (goiters) were distributed in 8 tissue microarray blocks and evaluated with immunohistochemistry using anti-CD133 and anti-ABCB5 antibodies. The expression of each marker alone and combined was analyzed against pathological characteristics and factors of worse prognosis in PTC. Expression of CD133 alone (19 tumors, 16.0%) was more frequent in patients with versus without lymph node metastases (P=0.024). Expression of ABCB5 alone (n=95, 83.3%) was associated with larger tumor size (P=0.045). CD133-ABCB5 coexpression was not associated with pathological characteristics or factors of worse prognosis in PTC.

OPN ABCB5, Background: Studies with biomarkers in TMA (tissue microarray) have been showing important results regarding its expression in colon cancer. Aim: Correlate the expression profile of the OPN and ABCB5 biomarkers with the epidemiological and clinicopathological characteristics of the patients, the impact on the progression of the disease and the death. Method: A total of 122 CRC patients who underwent surgical resection, immunomarking and their relationship with progression and death events were evaluated. Result: The average age was 61.9 (±13.4) years. The cases were distributed in 42 (35.9%) in the ascending/transverse colon, 31 (26.5%) in the sigmoid, 27 in the rectum (23.1%), 17 (14.5%) in the descending colon. Most patients had advanced disease (stages III and IV) in 74 cases (60.9%). There was a predominance of moderately differentiated tumors in 101 samples (82.8%); despite this, the poorly differentiated subtype proved to be an independent risk factor for death in 70%. Metastasis to the liver proved to be an independent risk factor for death in 75% (18/24), as well as patients with primary rectal tumors in 81.5% (22/27). Conclusion: The immunohistochemical expression of the OPN and ABCB5 markers was not associated with epidemiological and clinicopathological characteristics. Regarding the progression of disease and death, it was not possible to observe a correspondence relationship with the evaluated markers.

ABC member B5 (ABCB5) mediates multidrug resistance (MDR) in diverse malignancies and confers clinically relevant 5-fluorouracil resistance to CD133-expressing cancer stem cells in human colorectal cancer (CRC). Because of its recently identified roles in normal stem cell maintenance, we hypothesized that ABCB5 might also serve MDR-independent functions in CRC. Here, in a prospective clinical study of 142 CRC patients, we found that ABCB5 mRNA transcripts previously reported not to be significantly expressed in healthy peripheral blood mononuclear cells are significantly enriched in patient peripheral blood specimens compared with non-CRC controls and correlate with CRC disease progression. In human-to-mouse CRC tumor xenotransplantation models that exhibited circulating tumor mRNA, we observed that cancer-specific ABCB5 knockdown significantly reduced detection of these transcripts, suggesting that the knockdown inhibited tumor invasiveness. Mechanistically, this effect was associated with inhibition of expression and downstream signaling of AXL receptor tyrosine kinase (AXL), a proinvasive molecule herein shown to be produced by ABCB5-positive CRC cells. Importantly, rescue of AXL expression in ABCB5-knockdown CRC tumor cells restored tumor-specific transcript detection in the peripheral blood of xenograft recipients, indicating that ABCB5 regulates CRC invasiveness, at least in part, by enhancing AXL signaling. Our results implicate ABCB5 as a critical determinant of CRC invasiveness and suggest that ABCB5 blockade might represent a strategy in CRC therapy, even independently of ABCB5's function as an MDR mediator.

Generally regarded as commensal bacteria, the pathogenicity of Ureaplasma has often been considered low. Controversy remains concerning the clinical relevance of Ureaplasma infection in the pathogenesis of inflammation-related morbidities. Recently, we demonstrated Ureaplasma-driven pro-inflammatory cytokine responses in human monocytes in vitro. We hypothesized that Ureaplasma may induce further inflammatory mediators. Using qRT-PCR and multi-analyte immunoassay, we assessed the expression of granulocyte-colony stimulating factor (G-CSF), vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in term neonatal and adult monocytes exposed to Ureaplasma urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3). Ureaplasma significantly induced VEGF mRNA in neonatal (Up3: p 0.05, versus broth control) and adult monocytes (Uu8: p 0.05) as well as ICAM-1 mRNA in neonatal cells (p 0.05 each). As far as protein expression was concerned, Up3 stimulated VEGF release in both monocyte subsets (p 0.01) and enhanced secretion of ICAM-1 protein in neonatal monocytes (p 0.05). In adult cells, ICAM-1 protein release was increased upon exposure to both isolates (Uu8: p 0.05, Up3: p 0.01). Ureaplasma-induced responses did not significantly differ from corresponding levels mediated by E. coli lipopolysaccharide (LPS). The stimulatory effects were dose-dependent. Ureaplasma infection, on the contrary, did not affect G-CSF and VCAM-1 expression. Of note, co-infection of LPS-primed neonatal monocytes with Ureaplasma enhanced LPS-induced ICAM-1 release (Uu8: p 0.05). Our results confirm Ureaplasma-driven pro-inflammatory activation of human monocytes in vitro, demonstrating a differential modulation of growth factors and cell adhesion molecules, that might promote unbalanced monocyte responses and adverse immunomodulation.

Clear cell renal cell carcinoma (ccRCC) is the most lethal form of kidney cancer. Small molecule Vascular Endothelial Growth Factor Receptor (VEGFR) inhibitors are widely used but are not curative and various resistant mechanisms have been described. Previous studies have indicated a crosstalk between the cAMP pathway and the MAPK pathway, and the elevation of cAMP levels by Phosphodiesterase 4 (PDE4) inhibition can result in growth arrest and/or cell death. In this study we focused on the effects of PDE4 in ccRCC. We showed for the first time that PDE4D is the dominant subtype of PDE4 in kidney. PDE4D depletion in ccRCC, Caki-1 cells, using CRISPR Knock Out (KO) enhanced sensitivity of Tyrosine Kinase Inhibitor (TKI), sorafenib and increased cytotoxicity. We also showed synergistic effects of PDE4 inhibitor, roflumilast and sorafenib, in increasing cytotoxicity of ccRCC in the absence of PDE4D. Our results further demonstrated that PDE4D deficiency increased intracellular cAMP levels and resulted in downregulation of MAPK but not PI3K/AKT signaling in a CRAF dependent manners. In conclusion, we provide a preclinical rationale for dual PDE4/VEGFR inhibition in patients with ccRCC. While the MAPK signaling pathway is activated in ccRCC, dual inhibitions may improve the anti-tumor effects in patients with proven CRAF signaling activation. Citation Format: Minghua Cao, Amrandra K. Ajay, Martin Gasser, Li-LI Hsiao, Ana Maria Waaga-Gasser. Phosphodiesterase 4D depletion enhances anti-tumor effects of tyrosine kinase inhibitor in renal cell carcinoma involving CRAF-ERK pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 967.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest types of cancer with 5-year survival rates between 5-8%. Chronic inflammation of the pancreas and pancreatitis is thought to be a risk factor in PDAC. The aim of this study was to elucidate characteristic pro-inflammatory cytokines and chemokines including IL-17 profiles in human pancreatic cancer. A total of 186 individuals with confirmed PDAC (n=116), chronic pancreatitis (n=32), and healthy volunteers (n=38) were included in the study. The histological stage of the tumor was determined according to the Union for International Cancer Control (UICC) TNM staging system. Tumors were evaluated for stage and differentiation grade. Data concerning age, gender, level of wall infiltration, lymph node metastasis, and distant metastases were collected in a database. Additional clinical characteristics necessary for statistical analysis of the data from the study population were collected from the Tumor Registry. Inflammation-related cytokines and chemokines in IL-17 pathway among the patients were analyzed from serum obtained pre-operatively and compared with healthy controls. Moreover, the KEGG PATHWAY, a collection of manually drawn pathway maps on molecular interaction, reaction and relation networks was used for IL-17 pathway analysis. Non-parametric tests and correlation tests were utilized to compare the factors among three groups for statistical analysis. Pancreatitis patients showed highest expression in inflammatory cytokines and chemokine panels while those with PDAC showed different profiles. Pro-inflammatory cytokines including IL-5, IL-6, CXCL8, CCL2, TNF-alpha, and IFN-gamma revealed higher expression in PDAC patients than healthy volunteers (P Citation Format: Yueming Luo, Martin Gasser, Amrendra Ajay, Li-LI Hsiao, Ana Maria Waaga-Gasser. Pro-inflammatory serum marker profiles that lack upregulated IL-17 are characteristic for pancreatic cancer and require for further anti-tumor immune response and strategies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1758.

CD137-targeting immune therapy, which activates anti-tumor T effector cell responses, seems to be an attractive concept in clinical oncology. Recent evidence has demonstrated that tumor cells besides T cells and antigen-presenting cells are able to express CD137 and CD137L. Here we aimed to identify CD137/CD137L expression in established colon cancer cell lines and primary tumors (UICC stages I-IV) from patients with documented long-term follow-up. CD137/CD137L expression was highly upregulated in early to late-stage tumors while the inverse was observed in patient-derived peripheral blood mononuclear cells. High CD137L expression within primary tumors was mediated by tumor cells and significantly correlated with the occurrence of distant metastases and shortened survival in advanced stages of disease (UICC stage IV). Interestingly, induced tumor cell signaling via CD137L on its surface in vitro resulted in dual effects: (i) reduced tumor cell proliferation suggesting inhibitory signaling in all investigated cancers and (ii) increased epithelial-to-mesenchymal transition signaling events. Taken together CD137/CD137L expression was stage-dependently upregulated with shortened survival in patients with highly CD137L-expressing tumors. Our clinical and experimental data suggest that colon cancer cells predominantly express CD137L and thereby have negative impact on overall survival through a process of reverse signaling. Beside agonistic CD137 antibody therapy to foster T effector cell responses, CD137L-mediated intervention strategies may become instrumental to circumvent relapsed tumor growth through induced epithelial-to-mesenchymal transition and consecutive metastases formation.

Background Cardiovascular fibrosis is a major contributor to cardiovascular disease, the primary cause of death in patients with chronic kidney disease (CKD). We previously reported expression of endogenous Klotho in human arteries, and that CKD is a state of Klotho deficiency, resulting in vascular calcification, but myocardial expression of Klotho is poorly understood. This study aimed to further clarify endogenous Klotho's functional roles in cardiac fibrosis in patients with underlying CKD. Methods and results Human atrial appendage specimens were collected during cardiac surgery from individuals with or without CKD. Cardiac fibrosis was quantified using trichrome staining. For endogenous Klotho functional studies, primary human cardiomyocytes (HCMs) were treated with uremic serum from CKD patients or recombinant human TGF-β1. The effects of endogenous Klotho in HCMs were studied using Klotho-siRNA and Klotho-plasmid transfection. Both gene and protein expression of endogenous Klotho are found in human heart, but decreased Klotho expression is clearly associated with the degree of cardiac fibrosis in CKD patients. Moreover, we show that endogenous Klotho is expressed by HCMs and cardiac fibroblasts (HCFs) but that HCM expression is suppressed by uremic serum or TGF-β1. Klotho knockdown or overexpression aggravates or mitigates TGF-β1-induced fibrosis and canonical Wnt signaling in HCMs, respectively. Furthermore, co-culture of HCMs with HCFs increases TGF-β1-induced fibrogenic proteins in HCFs, but overexpression of endogenous Klotho in HCMs mitigates this effect, suggesting functional crosstalk between HCMs and HCFs. Conclusions Our data from analysis of human hearts as well as functional in vitro studies strongly suggests that the loss of cardiac endogenous Klotho in CKD patients, specifically in cardiomyocytes, facilitates intensified TGF-β1 signaling which enables more vigorous cardiac fibrosis through upregulated Wnt signaling. Upregulation of endogenous Klotho inhibits pathogenic Wnt/β-catenin signaling and may offer a novel strategy for prevention and treatment of cardiac fibrosis in CKD patients.

Introduction: The purpose of this study was to determine the efficacy of an immunoglobulin concentrate on dysregulated inflammatory responses in patients with colorectal cancer (CRC). Recent findings have shown that CRC is associated with dysbiosis of the gut microbiome and frequently a compromised gut barrier, resulting in prolonged and smoldering endotoxin leakage into the circulation. Subclinical local and systemic microinflammation is suggested to facilitate metastasis formation. Previous studies have pointed to the capacity of polyvalent immunoglobulins to neutralize endotoxins and pathogens on gut epithelial surfaces to abrogate inflammatory responses and thereby tumor recurrence. The effects of KMP01D, a colostrum preparation with a multitude of immunoglobulins against gram-negative/positive bacteria and viruses, on pro-/anti-inflammatory cytokine responses and apoptosis were determined ex vivo. Methods: Peripheral blood and tumor-derived mononuclear cells (MNC) from CRC patients at UICC stages I–IV (n=48) operated at our Center for Operative Medicine/Comprehensive Cancer Center and treated under current guidelines for (neo-)adjuvant therapy were further investigated. Expression of CD14, CD68, Toll-like receptor(TLR) 4, and insulin-like growth factor (IGF)-1 with/without co-incubation of KMP01D as well as immune cell apoptosis was analyzed by flow cytometry, RT PCR, immunohistochemistry, and Elisa in each patient. Results: KMP01D increased interleukin (IL)-10 and IL-13 anti-inflammatory cytokine expression in peripheral blood MNCs (UICC I-III). More interestingly, it likewise decreased secretion of IL-1β, IL-6, IFN-γ, TNF-α, and IL-12 driven inflammation as well as IGF-1. Moreover, CD14/CD68 and TLR4 expression critically involved in endotoxin signaling was downregulated in PBMCs and tumor-infiltrating MNCs. CD14+Fas+/TUNEL+ PBMCs and tumor-derived MNCs indicating apoptosis were likewise enhanced under KMP01D co-incubation. Addition of vitamin D3 known as a regulatory factor in immune responses demonstrated additive anti-inflammatory effects in vitro. Conclusions: Inflammatory immune responses are significantly and stage-dependently upregulated which negatively impacts anti-tumor-specific immune reactivity, immune cell apoptosis and prognosis in CRC patients despite modern adjuvant treatment protocols. KMP01D produced from natural bovine sources and composed of a multitude of immunoglobulin activity (IgG1/2 and Lactoferrin) demonstrates highly ex vivo efficacy on downregulation of inflammatory cytokine responses in PBMCs and normalized immune cell apoptosis in CRC patients. Together with previous clinical data our results strongly suggest that KMP01-mediated endotoxin and pathogen neutralization and thereby mitigated chronic inflammation can be a highly valuable add-on instrument in the treatment of CRC patients to downregulate stage-dependently their local and systemic inflammation and risk for metastasis formation. Citation Format: Martin Gasser, Reinhard Lissner, Li-Li Hsiao, Ana Maria Waaga-Gasser. Results from a preclinical study to evaluate the efficacy of polyvalent immunoglobulins on the imbalance of (anti-)inflammatory immune cell responses in clinical colorectal cancer [abstract]. In: Abstracts: AACR Virtual Special Conference: Tumor Immunology and Immunotherapy; 2020 Oct 19-20. Philadelphia (PA): AACR; Cancer Immunol Res 2021;9(2 Suppl):Abstract nr PO001.

// Romana Moench 1 , Tanja Grimmig 1 , Vinicius Kannen 2 , Sudipta Tripathi 3 , Marc Faber 1 , Eva-Maria Moll 1, † , Anil Chandraker 3 , Reinhard Lissner 1 , Christoph-Thomas Germer 4 , Ana Maria Waaga-Gasser 1, 3, * , Martin Gasser 4, * 1 Department of Surgery I, Molecular Oncology and Immunology, University of Wuerzburg, Wuerzburg, Germany 2 Ribeirao Preto Pharmaceutical Sciences School, Department of Toxicology, Bromatology, and Clinical Analysis, University of Sao Paulo, Sao Paulo, Brazil 3 Brigham and Women’s Hospital, Transplant Research Center, Harvard Medical School, Boston, MA, USA 4 Department of Surgery I, University of Wuerzburg, Wuerzburg, Germany † Post mortem * These authors have contributed equally to this work and shared senior authorship Correspondence to: Ana Maria Waaga-Gasser, email: waaga_a@ukw.de Keywords: PDGF, colorectal cancer, PI3K/Akt/mTOR, MAPK pathway, glucose metabolism Received: January 21, 2016 Accepted: August 08, 2016 Published: September 08, 2016 ABSTRACT Platelet-derived growth factor (PDGF) and signaling via its receptors plays a crucial role in tumor cell proliferation and thus may represent an attractive target besides VEGF/EGFR-based antibody therapies. In this study we analyzed the influence of PDGF in colorectal cancer. PDGF was expressed intensively in early and even more intensively in late stage primary CRCs. Like VEGF, PDGF enhanced human colon cancer proliferation, and increased oxidative glycolytic activity, and activated HIF1α and c-Myc in vitro . PDGF activated the PI3K/Akt/mTOR pathway while leaving MAPK signaling untouched. Further dissection showed that inhibition of Akt strongly impeded cancer cell growth while inhibition of PI3K did not. MAPK analysis suggested an inhibitory crosstalk between both pathways, thus explaining the different effects of the Akt and PI3K inhibitors on cancer cell proliferation. PDGF stimulates colon cancer cell proliferation, and prevents inhibitor induced apoptosis, resulting in tumor growth. Therefore inhibition of PDGF signaling seems to be a promising target in colorectal cancer therapy. However, due to the multifaceted nature of the intracellular PDGF signaling, careful intervention strategies are needed when looking into specific signaling pathways like PI3K/Akt/mTOR and MAPK.

Tumor models based on cancer cell lines cultured two-dimensionally (2D) on plastic lack histological complexity and functionality compared to the native microenvironment. Xenogenic mouse tumor models display higher complexity but often do not predict human drug responses accurately due to species-specific differences. We present here a three-dimensional (3D) in vitro colon cancer model based on a biological scaffold derived from decellularized porcine jejunum (small intestine submucosa+mucosa, SISmuc). Two different cell lines were used in monoculture or in coculture with primary fibroblasts. After 14 days of culture, we demonstrated a close contact of human Caco2 colon cancer cells with the preserved basement membrane on an ultrastructural level as well as morphological characteristics of a well-differentiated epithelium. To generate a tissue-engineered tumor model, we chose human SW480 colon cancer cells, a reportedly malignant cell line. Malignant characteristics were confirmed in 2D cell culture: SW480 cells showed higher vimentin and lower E-cadherin expression than Caco2 cells. In contrast to Caco2, SW480 cells displayed cancerous characteristics such as delocalized E-cadherin and nuclear location of beta-catenin in a subset of cells. One central drawback of 2D cultures-especially in consideration of drug testing-is their artificially high proliferation. In our 3D tissue-engineered tumor model, both cell lines showed decreased numbers of proliferating cells, thus correlating more precisely with observations of primary colon cancer in all stages (UICC I-IV). Moreover, vimentin decreased in SW480 colon cancer cells, indicating a mesenchymal to epithelial transition process, attributed to metastasis formation. Only SW480 cells cocultured with fibroblasts induced the formation of tumor-like aggregates surrounded by fibroblasts, whereas in Caco2 cocultures, a separate Caco2 cell layer was formed separated from the fibroblast compartment beneath. To foster tissue generation, a bioreactor was constructed for dynamic culture approaches. This induced a close tissue-like association of cultured tumor cells with fibroblasts reflecting tumor biopsies. Therapy with 5-fluorouracil (5-FU) was effective only in 3D coculture. In conclusion, our 3D tumor model reflects human tissue-related tumor characteristics, including lower tumor cell proliferation. It is now available for drug testing in metastatic context-especially for substances targeting tumor-stroma interactions.

Anti-Epithelial/Vascular Endothelial Growth Factor (EGF/VEGF)-targeted therapy plays important roles in advanced stage colorectal cancer (CRC) patients but fails to show clinical efficacy in specific subgroups which lack of clear underlying mechanisms. In vitro studies indicated that cross-talk or alternative receptor/ligand activities can bypass anti-growth factor signaling arrest and therefore may explain failure of monoclonal antibody (mAb) targeted therapy. In this study we analyzed effects of Platelet Derived Growth Factor (PDGF)-mediated bypassed signaling in CRC. We first investigated human UICC (Union for International Cancer Control ) stage I-IV tumors (n=46) from our Center and found increased PDGFRβ and VEGFR1/2 gene expression (p Citation Format: Romana Moench, Martin Gasser, Karol Nawalaniec, Tanja Grimmig, Minghua Cao, Yueming Luo, Li-Li Hsiao, Ana Maria Waaga-Gasser. PDGF-induced tumor cell growth despite VEGF/EGF inhibition and absence of PDGF receptor expression in colon cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3755.

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignancy characterized by delayed diagnosis and the lowest five-year survival amongst all cancer sites. PDAC development and progression are attributed to chronic inflammation and associated tissue repair mechanisms which contribute to high density tumor formation and chemoresistance. PDAC-associated inflammation is, in part, owed to high levels of interleukin 6 (IL-6) and its activated pathways including JAK/STAT3. In Addition, Fibroblast growth factor (FGF) signaling pathways are known to be dysregulated in cancer and have been implicated in various malignancies including PDAC. As such, we sought to explore the association between IL-6-induced inflammatory signaling and FGF signaling activation. To observe this effect as it pertains to carcinogenesis and cancer progression we used four human cell lines ranging from healthy pancreatic ductal epithelial (HPDE) cells to various grade (G) PDAC cells. Cells were treated with IL-6 at a concentration of 100 ng/mL for 24 hours. The results showed increased phosphorylation of STAT3 in BxPC-3 (G2) and PANC-1 (G3) cells with no change noted in HPDE and SW1990 (G2, metastatic) cells. IL-6 stimulation likewise resulted in markedly increased phosphorylation of the fibroblast growth factor receptor substrate 2-alpha (FRS2-α) and its downstream component Erk1/2 in BxPC3 cells, indicating activation of FGF signaling through the MAPK/Erk pathway in our low grade PDAC cell model. In conclusion, the results demonstrate a potential link between IL-6 induced inflammatory signaling and dysregulation of FGF signaling in human PDAC. Activated STAT3 signaling seems to be involved in this process. Existing cancer therapies aimed at controlling growth factor signaling broadly target vascular endothelial or epithelial growth factor receptors (VEGF/EGFR) with marginal efficacy and adverse side effects in PDAC. Identifying the pivotal link between inflammatory signaling and dysregulation of fibroblast growth factor signaling will allow for the development of more precisely targeted and effective cancer therapy in pancreatic cancer. This may minimize clinically observed exaggerated fibrotic events within the tumor and may hence result in higher vulnerability for established chemotoxic therapies in the tumor cells. Citation Format: Karol Nawalaniec, Yuxiang Wang, Romana Moench, Minghua Cao, Yueming Luo, Li-Li Hsiao, Ana Maria Waaga-Gasser. IL-6/STAT3-mediated inflammatory signaling results in dysregulated fibroblast growth factor receptor activation and tumor cell signaling in human pancreatic adenocarcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 992.

Purpose: To compare wound healing performed with cold blade (CSB) and ultrasonic harmonic scalpel (UHS) in the abdominal aponeurosis of rats. Methods: Eighty Wistar rats divided into two groups and underwent midline incision in the linea alba with cold blade and harmonic ultrasonic scalpel. Analysis were performed in subgroups of 10 animals after 3, 7, 14 and 21 days. Macroscopically was observed the presence of hematoma, infection, wound dehiscence, fistula and adherences. Microscopically were used collagen and immunohistochemical staining methods. Results: Macroscopic, complications showed no statistical difference. Immunohistochemical analysis for MMP-9 was more intense in UHS group (p

Mold specific T-cells have been described as a supportive biomarker to monitor invasive mycoses and mold exposure. This study comparatively evaluated frequencies and cytokine profiles of Aspergillus fumigatus and Mucorales reactive T-cells depending on environmental mold exposure. Peripheral blood mononuclear cells (PBMCs) obtained from 35 healthy donors were stimulated with mycelial lysates of A. fumigatus and three human pathogenic Mucorales species. CD154+ specific T-cells were quantified by flow cytometry. In a second cohort of 20 additional donors, flow cytometry was complemented by 13-plex cytokine assays. Mold exposure of the subjects was determined using a previously established questionnaire. Highly exposed subjects exhibited significantly greater CD154+ A. fumigatus and Mucorales specific naive and memory T-helper cell frequencies. Significant correlation (r = 0.48 – 0.79) was found between A. fumigatus and Mucorales specific T-cell numbers. Logistic regression analyses revealed that combined analysis of mold specific T-cell frequencies and selected cytokine markers (A. fumigatus: IL-5 and TNF-α, R. arrhizus: IL-17A and IL-13) significantly improves classification performance, resulting in 75–90 % predictive power using 10-fold cross-validation. In conclusion, mold specific T-cell frequencies and their cytokine signatures offer promising potential in the assessment of environmental mold exposure. The cytokines identified in this pilot study should be validated in the clinical setting, e. g. in patients with hypersensitivity pneumonitis.

Colon cancer is one of the most common tumors in the human population. Recent studies have shown a reduced risk for colon cancer in patients given the antidepressant fluoxetine (FLX). The exact mechanism by which FLX might protect from colon cancer remains however controversial. Here, FLX reduced the development of different colon tumor xenografts, as well as proliferation in hypoxic tumor areas within them. FLX treatment also decreased microvessel numbers in tumors. Although FLX did not increase serum and tumor glucose levels as much as the colon chemotherapy gold standard Fluorouracil did, lactate levels were significantly augmented within tumors by FLX treatment. The gene expression of the MCT4 lactate transporter was significantly downregulated. Total protein amounts from the third and fifth mitochondrial complexes were significantly decreased by FLX in tumors. Cell culture experiments revealed that FLX reduced the mitochondrial membrane potential significantly and disabled the reactive oxygen species production of the third mitochondrial complex. Furthermore, FLX arrested hypoxic colon tumor cells in the G0/G1 phase of the cell-cycle. The expression of key cell-cycle-related checkpoint proteins was enhanced in cell culture and in vivo experiments. Therefore, we suggest FLX impairs energy generation, cell cycle progression and proliferation in tumor cells, especially under condition of hypoxia. This then leads to reduced microvessel formation and tumor shrinkage in xenograft models.

Chronic inflammation as an important epigenetic and environmental factor for putative tumorigenesis and tumor progression may be associated with specific activation of Toll-like receptors (TLR). Recently, carcinogenesis has been suggested to be dependent on TLR7 signaling. In the present study, we determined the role of both TLR7 and TLR8 expression and signaling in tumor cell proliferation and chemoresistance in pancreatic cancer. Expression of TLR7/TLR8 in UICC stage I-IV pancreatic cancer, chronic pancreatitis, normal pancreatic tissue and human pancreatic (PANC1) cancer cell line was examined. For in vitro/in vivo studies TLR7/TLR8 overexpressing PANC1 cell lines were generated and analyzed for effects of (un-)stimulated TLR expression on tumor cell proliferation and chemoresistance. TLR expression was increased in pancreatic cancer, with stage-dependent upregulation in advanced tumors, compared to earlier stages and chronic pancreatitis. Stimulation of TLR7/TLR8 overexpressing PANC1 cells resulted in elevated NF-κB and COX-2 expression, increased cancer cell proliferation and reduced chemosensitivity. More importantly, TLR7/TLR8 expression increased tumor growth in vivo. Our data demonstrate a stage-dependent upregulation of both TLR7 and TLR8 expression in pancreatic cancer. Functional analysis in human pancreatic cancer cells point to a significant role of both TLRs in chronic inflammation-mediated TLR7/TLR8 signaling leading to tumor cell proliferation and chemoresistance.

The receptor tyrosine kinase c-Met is overexpressed in renal cancer cells and can play major role in the growth and survival of tumor. We investigated how the c-Met-mediated signaling through binding to its ligand hepatocyte growth factor (HGF) can modulate the apoptosis and immune escape mechanism(s) of renal cancer cells by the regulations of novel molecules heme oxygenase-1 (HO-1) and programmed death-1 ligand 1 (PD-L1). We found that HGF/c-Met-mediated signaling activated the Ras/Raf pathway and down-regulated cancer cell apoptosis; and it was associated with the overexpression of cytoprotective HO-1 and anti-apoptotic Bcl-2/Bcl-xL. c-Met-induced HO-1 overexpression was regulated at the transcriptional level. Next, we observed that c-Met induction markedly up-regulated the expression of the negative co-stimulatory molecule PD-L1, and this can be prevented following treatment of the cells with pharmacological inhibitors of c-Met. Interestingly, HGF/c-Met-mediated signaling could not induce PD-L1 at the optimum level when either Ras or HO-1 was knocked down. To study the functional significance of c-Met-induced PD-L1 expression, we performed a co-culture assay using mouse splenocytes (expressing PD-L1 receptor PD-1) and murine renal cancer cells (RENCA, expressing high PD-L1). We observed that the splenocyte-mediated apoptosis of cancer cells during co-culture was markedly increased in the presence of either c-Met inhibitor or PD-L1 neutralizing antibody. Finally, we found that both c-Met and PD-L1 are significantly up-regulated and co-localized in human renal cancer tissues. Together, our study suggests a novel mechanism(s) by which c-Met can promote increased survival of renal cancer cells through the regulation of HO-1 and PD-L1.

Purpose: The programmed death-1/programmed death ligand (PD-1/PD-L) pathway in T cell activation has been shown to play an important role in tumor evasion from host immunity. The predictive value of PD-L1 and PDL2 expression in colorectal cancer (CRC) remains still under discussion. We analyzed whether negative signaling of infiltrating PD-1-positive T cells through PD-L1 and PD-L2 within the tumor could promote further tumor progression through downregulation of anti-tumor immunity. Methods: We investigated PD-L1 and PD-L2 expression in tumors from patients with CRC and analyzed its prognostic significance with respect to outcome analysis. Results: T cell infiltration was observed in 90.5% of the tumors, with 58% of the patients demonstrating PD-1- positive T cells in their tumors. Patients who developed PD-1-positive T cell infiltration showed increased PD-L1- expression within their tumors than PD-1-T cell negative individuals. Presence of tumor infiltrating PD-1-positive T cells was more pronounced in advanced stage cancers than in early cancers. Ligand expression (PD-L1/PD-L2) in the tumors combined with dense PD-1-positive T cell infiltration was associated with poor prognosis. Multivariate analysis demonstrated that PD-L expression in the tumors was an independent prognostic factor in CRC. Conclusion: The presented results from primary tumors and CRC patient outcome analysis suggest that negative signaling of infiltrating PD-1-positive T cells through PD-L1 expression within the tumor may promote further tumor progression through downregulation of anti-tumor immunity. Co-expression of PD-1 on CD4/Foxp3- positive T cells was found indicating T regulatory cell-mediated mechanisms by which tumor cells can evade immune recognition and destruction. This study demonstrates the importance of strategies inhibiting negative PD-1/ PD-L1 signaling in CRC.

Purpose: Disseminated tumor cells (DTCs) are critically involved in tumor relapse and survival in several invasive tumors. We previously showed that the ATP-binding cassette (ABC) transporter, ABCB5, is a chemoresistance mediator expressed on specific cell subsets in colorectal cancer (CRC) and other malignancies. This study evaluated the molecular signature expression and its clinical relevance of DTCs in bone marrow from patients with colon cancer. Methods: This study included 49 consecutive patients (UICC stage I-IV) that underwent curatively intended or palliative surgery for CRC. We analyzed cells from bone marrow aspirates obtained before surgery and derived from patients that had completed minimally a 5-year follow-up. The gene expression of ABCB5 in comparison to CD133 (molecule for identifying cancer initiating cells), Lgr5 (an intestinal stem cell marker) as well as Cytokeratin (CK) 20 (terminally differentiated tumor cells of epithelial origin) in these cells was evaluated. Results: Bone marrow analysis showed differential expression between the analyzed genes. ABCB5 and Lgr5 and to lesser extent CD133 and CK20 genes were significantly expressed in the analyzed cells from bone marrow aspirates while only ABCB5 and Lgr5 were significantly negative associated with tumor progress and overall survival. Conclusion: Overexpression of ABCB5 and Lgr5 in bone marrow negatively influenced patient survival pointing to a specific chemo resistant and pluripotent cell subgroup of DTCs in the bone marrow. ABCB5 like Lgr5 positive cells seem to be involved in limited tumor related patient survival, suggesting that ABCB5- and Lgr5-positive cells may be relevant for specific clinical intervention strategies.

In immunocompromised patients, invasive aspergillosis (IA) is the most frequent disease caused by the pathogenic mould Aspergillus fumigatus. Fever is one of the most common yet nonspecific clinical symptoms of IA. To evaluate the role of hyperthermia in the innate immune response to A. fumigatus in vitro, human monocyte-derived dendritic cells (DCs) were stimulated with germ tubes of A. fumigatus or the fungal cell wall component zymosan at 37°C or 40°C, followed by characterization of specific DC functions. While maturation of DCs was enhanced and DC phagocytic capacity was reduced at 40°C, we observed that DC viability and cytokine release were unaffected. Thus, our results suggest that hyperthermia has substantial impacts on DC function in vitro, which might also influence the course and outcome of IA in immunocompromised patients.

There is evidence that inflammatory processes are involved in at least the early phase of complex regional pain syndrome (CRPS). We compared a panel of pro- and antiinflammatory cytokines in skin blister fluids and serum from patients with CRPS and patients with upper-limb pain of other origin (non-CRPS) in the early stage (< 1 year) and after 6 months of pain treatment. Blister fluid was collected from the affected and contralateral nonaffected side. We used a multiplex-10 bead array cytokine assay and Luminex technology to measure protein concentrations of the cytokines interleukin-1 receptor antagonist (IL-1RA), IL-2, IL-6, IL-8, IL-10, IL-12p40, and tumor necrosis factor-alpha (TNF-α) and the chemokines eotaxin, monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1β (MIP-1β). We found bilaterally increased proinflammatory TNF-α and MIP-1β and decreased antiinflammatory IL-1RA protein levels in CRPS patients compared to non-CRPS patients. Neither group showed side differences. After 6 months under analgesic treatment, protein levels of all measured cytokines in CRPS patients, except for IL-6, significantly changed bilaterally to the level of non-CRPS patients. These changes were not related to treatment outcome. In serum, only IL-8, TNF-α, eotaxin, MCP-1, and MIP-1β were detectable without intergroup differences. Blister fluid of CRPS patients showed a bilateral proinflammatory cytokine profile. This profile seems to be relevant only at the early stage of CRPS. Almost all measured cytokine levels were comparable to those of non-CRPS patients after 6 months of analgesic treatment and were not related to treatment outcome.

The role of glucagon-like peptide 2 (GLP2) in colon tissue has been studied extensively, from the time it was discovered that GLP2 promotes intestinal growth. A large number of studies have shown potential applications for GLP2 in human therapy. However, recent data have suggested the notion that GLP2 plays a key role in colon carcinogenesis. Questions have been arisen regarding the pro-proliferative effects of GLP2 and whether they might promote intestinal healing or advance colon tumor growth. Here, we provide striking evidence to show that the physiological activities of GLP2 are closely related to cancer-related molecular pathways that have been shown to circumvent drug desensitization. We further explore the different pathways of GLP2-signaling to suggest suitable GLP2-based therapeutic strategies in colon cancer.

In patients with isolated peritoneal carcinomatosis (PC) of gastrointestinal cancer, hyperthermic intraperitoneal chemotherapy (HIPEC) represents a promising treatment option integrated into multimodal concepts. Heat shock proteins (HSP) seem to play a major role in cellular stress during HIPEC therapy. We analyzed differentially hyperthermic conditions and HSPs responsible for cell stress-mediated repair mechanisms in tumor tissues from patients who underwent HIPEC therapy and in an in vitro hyperthermic model.Tumor tissues from our patient cohort with isolated PC were selected for further analysis when representative material was available before and after HIPEC therapy. To further dissect the role of HSPs under conditions of hyperthermia, gene and protein expression was additionally determined, together with cellular apoptosis and proliferation in human HT-29 colon cancer cells.Differently up-regulated HSP70/72 and HSP90 gene and protein expression was found in all investigated patient tumors. In vitro studies confirmed observations from clinical tumor analysis as underlying HSP-mediated cell stress mechanisms. Moreover, results from proliferation and apoptosis assays combined with differentiated HSP expression analysis demonstrated the relevance of preselecting specific target temperatures to achieve optimal toxic effects on remaining tumor cells in vivo.Therapeutic approaches like HIPEC to achieve antiproliferative and apoptosis-inducing cellular effects in patients with PC are negatively influenced by highly conserved HSP mechanisms in tumor cells. This study shows for the first time that specific hyperthermic conditions are necessary to be established to achieve optimal toxic effects on tumor cells during HIPEC therapy, a finding that opens potentially new therapeutic strategies.

Calcineurin inhibitors (CNIs) may promote post-transplantation cancer through altered expression of cytokines and chemokines in tumor cells. We found that there is a potential cross-talk among CNI-induced signaling molecules and mTOR. Here, we utilized a murine model of post-transplantation cancer to examine the effect of a combination therapy (CNI + mTOR-inhibitor rapamycin) on allograft survival and renal cancer progression. The therapy prolonged allograft survival; and significantly attenuated CNI-induced post-transplantation cancer progression, with down-regulation of mTOR and S6-kinase phosphorylation. Also, rapamycin inhibited CNI-induced over-expression of the angiogenic cytokine VEGF, and the chemokine receptor CXCR3 and its ligands in post-transplantation tumor tissues.

Background Chemokines play a critical role in tumor initiation, progression, and metastasis and have been associated with poor prognosis in diverse malignancies. The prognostic impact of chemokines for renal cell cancer (RCC) remains to be defined. Methods Patients diagnosed with RCC and operated between 07/07 and 05/11 were differentially assessed for expression profiles of a series of chemokines and their receptors by RT-qPCR and Western Blot analysis (tumor and adjacent normal tissue, n=37) and by Luminex for corresponding serum expression levels. Results were statistically correlated with clinicopathologic parameters. Results Gene expression of CCL2, CCR7, CXCL12, CXCR3, CXCR5 and CX3CL1 chemokines was significantly down-regulated in tumor compared to normal tissue. The gene profile for CCR6 was positively correlated with tumor size and stage. A positive linear correlation was found between CXCL12 and tumor stage as well as between CX3CR1 and C-reactive protein. In contrast to clear cell RCCs those of a chromophobe type showed a significantly down-regulated gene expression for CCR6, CCL20, and CXCL12. The CXCR7 serum level was significantly increased in patients with tumor-related mortality during postoperative follow-up. Conclusions Chemokines may serve as novel diagnostic and prognostic biomarkers for RCC. Studies on larger collectives are required for further assessment of potential clinical application.

Identification and reversal of treatment resistance mechanisms of clinically refractory tumor cells is critical for successful cancer therapy. Here we show that ATP-binding cassette member B5 (ABCB5) identifies therapy-refractory tumor cells in colorectal cancer patients following fluorouracil (5-FU)–based chemoradiation therapy and provide evidence for a functional role of ABCB5 in colorectal cancer 5-FU resistance. Examination of human colon and colorectal cancer specimens revealed ABCB5 to be expressed only on rare cells within healthy intestinal tissue, whereas clinical colorectal cancers exhibited substantially increased levels of ABCB5 expression. Analysis of successive, patient-matched biopsy specimens obtained prior to and following neoadjuvant 5-FU–based chemoradiation therapy in a series of colorectal cancer patients revealed markedly enhanced abundance of ABCB5-positive tumor cells when residual disease was detected. Consistent with this finding, the ABCB5-expressing tumor cell population was also treatment refractory and exhibited resistance to 5-FU–induced apoptosis in a colorectal cancer xenograft model of 5-FU monotherapy. Mechanistically, short hairpin RNA–mediated ABCB5 knockdown significantly inhibited tumorigenic xenograft growth and sensitized colorectal cancer cells to 5-FU–induced cell killing. Our results identify ABCB5 as a novel molecular marker of therapy-refractory tumor cells in colorectal cancer patients and point to a need for consistent eradication of ABCB5-positive resistant tumor cell populations for more effective colorectal cancer therapy. Cancer Res; 71(15); 5307–16. ©2011 AACR.

Introduction The aim of the current study was to explore the clinico-oncological characteristics, and the therapeutic and survival parameters, of renal transplant recipients who developed de novo transitional cell carcinoma (TCC) over a 30-year period at the authors’ center. Methods Retrospective analysis of records from all registered patients who underwent kidney transplantation at the center between November 1979 and January 2010 who developed de novo TCC of the urinary tract. Results From all 2001 patients analyzed during the study period, 21 recipients developed 19 TCCs of the bladder and 6 TCCs of the upper urinary tract. Among bladder TCCs, 13 (68.4%) cases were confined to mucosa (pTa or carcinoma in situ, n = 7) or submucosa (pT1, n = 6) and 6 others (31.6%) infiltrated the detrusor muscle (≥p T2); the grading distribution was 5 cases of G1, 6 of G2 and 8 of G3. All recurrent cases (n = 8) revealed local or systemic progression. The overall and tumor-specific patient survival rates were 80.2%, 54.0% and 30.0% and 84.9%, 67.4% and 58.9% for 1, 5 and 10 years, respectively. Conclusions In the light of the observed increased aggressiveness of TCC in renal transplant recipients, more frequent examinations and possibly more invasive follow-up protocols should be considered for patients with 1 or more risk factors for development of TCC. Urine cytology (including ureteral wash cytology) may be used as a reliable diagnostic tool in these patients. Prophylactic contralateral nephroureterectomy might be an option in patients at high risk.

Chronic transplant dysfunction, a major impediment to long-term allograft survival, is caused by several factors including an ongoing alloimmune response termed chronic rejection. To define some of these factors further, we selected 107 patients mismatched to their donors from 623 patients transplanted at a single center. Patients were categorized according to their immunosuppressive treatment and further divided into those with stable or chronic allograft dysfunction. Donor human lymphocyte antigen allopeptide-specific T-cell lines were then generated from stable patients and those with biopsy-proven chronic allograft nephropathy. Increased amounts of CD4+CD25+ regulatory T cells (Tregs) and Treg-associated gene expression profiles were found in cell lines derived from the patients with stable compared with those with chronic allograft dysfunction. Furthermore, a higher percentage of Tregs was found in patients with stable graft function on tacrolimus-based compared with cyclosporine-based immunosuppression protocols. Patients with stable graft function had a significantly higher expression of interleukin (IL)-4 and IL-10, whereas the cytokines IL-2, IL-17, and interferon-γ were significantly higher in patients with allograft dysfunction in vitro. Thus, enhancing the operational role of naturally occurring donor-specific Tregs in allograft recipients by adjusting the immunosuppression protocol may be advantageous particularly for patients with ongoing chronic rejection.

The chemokine receptor CXCR3 may play a critical role in the growth and metastasis of tumor cells, including renal tumors. It has been shown that CXCR3 has two splice variants with completely opposite functions; CXCR3-A promotes cell proliferation, whereas CXCR3-B inhibits cell growth. We recently demonstrated that the expression of growth-promoting CXCR3-A is up-regulated, and the growth-inhibitory CXCR3-B is markedly down-regulated in human renal cancer tissues; and the overexpression of CXCR3-B in renal cancer cells can significantly inhibit cell proliferation. However, the growth-inhibitory signal(s) through CXCR3-B are not well characterized. Here, we investigated the effector molecule(s) involved in CXCR3-B-mediated signaling events. We found that the overexpression of CXCR3-B in human renal cancer cells (Caki-1) promoted cellular apoptosis as observed by FACS analysis through Annexin-V staining. To examine whether the overexpression of CXCR3-B could alter the expression of any apoptosis-related genes in renal cancer cells, we performed a protein array. We found that CXCR3-B overexpression significantly down-regulated the expression of antiapoptotic heme oxygenase-1 (HO-1). By utilizing a HO-1 promoter-luciferase plasmid, we showed that CXCR3-B-mediated down-regulation of HO-1 was controlled at the transcriptional level as observed by luciferase assay. We also demonstrated that the inhibition of HO-1 expression using siRNA promoted apoptosis of renal cancer cells. Finally, we observed that human renal cancer tissues expressing low amounts of CXCR3-B significantly overexpress HO-1 at both mRNA and protein level. Together, we suggest that the overexpression of CXCR3-B may prevent the growth of renal tumors through the inhibition of antiapoptotic HO-1.

Circulating tumor cells (CTC) have been identified in several human malignancies, including malignant melanoma. However, whether melanoma CTC are tumorigenic and cause metastatic progression is currently unknown. Here, we isolate for the first time viable tumorigenic melanoma CTC and demonstrate that this cell population is capable of metastasis formation in human-to-mouse xenotransplantation experiments. The presence of CTC among peripheral blood mononuclear cells (PBMC) of murine recipients of subcutaneous (s.c.) human melanoma xenografts could be detected based on mRNA expression for human GAPDH and/or ATP-binding cassette subfamily B member 5 (ABCB5), a marker of malignant melanoma-initiating cells previously shown to be associated with metastatic disease progression in human patients. ABCB5 expression could also be detected in PBMC preparations from human stage IV melanoma patients but not healthy controls. The detection of melanoma CTC in human-to-mouse s.c. tumor xenotransplantation models correlated significantly with pulmonary metastasis formation. Moreover, prospectively isolated CTC from murine recipients of s.c. melanoma xenografts were capable of primary tumor initiation and caused metastasis formation upon xenotransplantation to secondary murine NOD-scid IL2Rγ(null) recipients. Our results provide initial evidence that melanoma CTC are tumorigenic and demonstrate that CTC are capable of causing metastatic tumor progression. These findings suggest a need for CTC eradication to inhibit metastatic progression and provide a rationale for assessment of therapeutic responses of this tumorigenic cell population to promising emerging melanoma treatment modalities.

Toll-like receptor (TLR) stimulation results in activation of NF-κB, a key modulator in driving inflammation to cancer and mitogen-activated protein kinases that have been shown to recruit mitotic and cyclooxygenase-2 (COX-2) induced pathways in carcinogenesis. Here we asked whether different TLR, COX-2 and stem cell marker expression profiles in colorectal cancer (CRC) provide further evidence for this hypothesis from a clinical perspective. We analysed gene and protein expression of TLR7-TLR10, COX-2 and CD133 as a marker for colon-initiating cells in CRC patients (n=65). Gene analysis demonstrated significantly upregulated TLR7-TLR10 and COX-2 expression in CRC tumour tissues. Analysis of isolated tumour cells from primary tumours showed co-expression of TLR7 and TLR8 with CD133 and gave evidence for a subpopulation of colon cancer-initiating cells. In multivariate analyses TLR8 expression was found to be an independent prognostic factor. Persistent TLR-specific activation of NF-κB in CRC and particularly in tumour-initiating cells may thus sustain further tumour growth and progression through perpetuated signalling known from inflammatory and tissue repair mechanisms with consecutive self-renewal in pluripotent tumour cells. Activation through self-ligands or viral RNA fragments may putatively maintain this inflammatory process, suggesting a key role in cancer progression.

Expression of apoptosis-related proteins on tumour cells has been shown in several experimental models to be an efficient mechanism for a counterattack against host anti-tumour immune responses in solid tumours. Here we provide a clinical evidence for such a tumour immune escape mechanism by demonstrating tumour to T cell-directed death receptor signalling (TRAIL/TRAIL-Receptor (TRAIL-R)) in colorectal cancer (CRC). In a series of patients with CRC and completed 5-year follow up, we investigated apoptosis and expression levels of apoptosis-related proteins. Gene and protein profiles in the tumours demonstrated intratumoural upregulated gene expression for Fas, Fas-L, TRAIL, TRAIL-R and TNF-alpha (RT-qPCR). Levels of terminaldeoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labelling (TUNEL)-positive events were positively correlated with TRAIL-R1-expression on tumour infiltrating immune cells. Among the immune cells, preferentially CD8+ T cells were found to express TRAIL-R1 while serial immunostaining in the same patient tumours showed abundant apoptotic (TUNEL-positive) immune cells. In conclusion, our results in tumour samples from CRC patients suggest TRAIL-R1-mediated apoptotic depletion of infiltrating immune cells (CD8+) in response to TRAIL expression by the tumour itself. This supports the notion of an efficient escape from tumour immune response and thus evasion from the attack of activated CD8+ T cells. These findings may enhance our understanding of tumour progression in CRC and might be helpful for the development of TRAIL and its death receptor-based therapy.

Objective The objective of this clinical pilot study was to examine the induction of apoptosis in mononuclear cells on treatment of patients with chronic pain syndrome with oral immunoglobulin produced from bovine colostrum (BCC). Design The 4 patients suffering from chronic idiopathic pain (idiopathic facial pain, CRPS or fibromyalgia) who were enrolled in the study had previously successfully been treated with BCC (varying individual doses). Mononuclear cells from peripheral blood were analyzed for representative cytokines in the serum as well as by TUNEL-assay to detect apoptotic cellular events 14 days after the last treatment with BCC and 14 days after restarting the treatment protocol with BCC. The clinical response (pain and quality of life parameters using a visual analogue scale (VAS)) were determined regularly in each patient. Results The findings showed a disturbed apoptosis homeostasis in 3 of the 4 patients. These results were accompanied by a relief of the pain symptoms. The 4th patient was found not to need any further analgetic treatment since she demonstrated only nonsignificant changes in her laboratory screening and immunological parameters and by the end of the study she was also completely free of pain (long-term treatment with BCC). Conclusions In spite of the low patient number, the results were obtained with a sufficiently high degree of control because of the study design. The agreement of the clinical data with our laboratory measurements suggests that the induction of apoptotic events in mononuclear cells is the result of the dominant immunological effects of BCC treatment.

Background: The development of therapeutic strategies for treatment of metastasized colorectal carcinoma requires biologically relevant and adequate animal models generating both metastases and the dissemination of tumor cells. Methods: To prove the efficiency of orthotopic implantation concerning induction of minimal residual disease (MRD) colorectal cancer tissue from 10 patients was transplanted orthotopically into nude mice. In the intraportal injection model 1 × 106 HT-29 human colon cancer cells were injected. We investigated by histological studies and CK-20 RT-PCR the occurrence of hematogenous metastases and the dissemination of human colon cancer cells in bone marrow. Results: Following orthotopic implantation of human colon cancer tissue the lymph node and hepatic metastasis rates were low. MRD as reflected by CK-20 positivity of the bone marrow was present in 22.2%. The intraportal injection of 1 × 106 HT-29 human colon cancer cells produced hepatic metastases in up to 89% of all animals. The intraportal injection of 1 × 106 cells also generated MRD in the bone marrow in 63% of animals. Conclusions: The intraportal injection model represents a biologically relevant and adequate animal model for the induction of both reproducible hepatic metastasis and MRD in the bone marrow. In this regard it seems to be superior to the orthotopic implantation model.

Calcineurin inhibitors (CNI) are used to prevent inflammatory diseases and allograft rejection. However, little is known about the mechanism(s) underlying their ability to promote the development and recurrence of cancer. Recent studies suggested that the chemokine receptor CXCR3 may play important roles in tumorigenesis. CXCR3 has two splice variants with opposite functions: CXCR3-A promotes cell proliferation, and CXCR3-B inhibits cell growth. Here, we explored the effects of CNI on the expression and function of CXCR3 splice variants. Compared with normal renal tissues and renal epithelial cells, human renal cancer tissues and renal cancer cell lines demonstrated higher expression of CXCR3-A and markedly lower expression of CXCR3-B. In human renal cancer cells (786-0 and Caki-1) and renal epithelial cells, CNI markedly downregulated the expression of CXCR3-B, whereas expression of CXCR3-A was unchanged. This CNI-mediated downregulation of CXCR3-B resulted in increased proliferation and migration of renal cancer cells; CNI-mediated cell proliferation involved signaling through G(i) proteins, perhaps via CXCR3-A. Finally, it was observed that CNI treatment increased the growth of human renal tumors in vivo, and the expression of CXCR3-B was significantly decreased in these tumors. In summary, these observations suggest that CNI may mediate the progression of human renal cancer by downregulating CXCR3-B and by promoting proliferative signals, likely through CXCR3-A. Targeting CXCR3 splice variants or the signaling pathways downstream of CXCR3 receptors may provide a therapeutic strategy for the prevention of CNI-mediated renal cancer progression.

Advances in the medical treatment of colorectal cancer patients have resulted in considerable improvements through the introduction of new cytotoxic drugs. The significant progress in molecular and tumour biology has produced a great number of targeted, tumour-specific, monoclonal antibodies that are now in various stages of clinical development. Two of these antibodies, cetuximab (Erbitux) und bevacizumab (Avastin), directed against the epidermal growth factor receptor (EGFR) and the vascular epithelial growth factor (VEGF), respectively, have recently been approved for use in metastatic colorectal cancer. The combination of well-known and newly developed cytotoxic agents with monoclonal antibodies makes the medical treatment of colorectal cancer patients considerably more complex, but also provides additional therapeutic strategies for patients in advanced stages of disease.

The therapeutic arsenal in solid tumors comprises different anticancer strategies with diverse chemotherapeutic agents and a growing number of biological substances. Large clinical study-based chemotherapeutic protocols combined with biologicals have become an important component in (neo-) adjuvant therapy alongside surgery in solid cancers as well as radiation therapy in some instances. In recent years, monoclonal antibodies have entered the mainstream of cancer therapy. Their first use was as antagonists of oncogenic receptor tyrosine kinases, but today monoclonal antibodies have emerged as long-sought vehicles for the targeted delivery of potent chemotherapeutic agents and as powerful tools to manipulate anticancer immune responses. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the clinical relevance of this approach.Targeted cancer therapies , also referred to as personalized medicine, are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The use of monoclonal antibodies in colorectal and gastric cancer for example have shown best outcome when combined with chemotherapy, even though single agent anti-EGFR antibodies seem to be active in particular setting of metastatic colorectal cancer patients. However, it is not well defined whether the addition of anti-VEGF - and anti-EGFR strategies to chemotherapy could improve outcome in those patients susceptible to colorectal cancer-related metastases resection. Among the most promising approaches to activating therapeutic antitumor immunity is the blockade of immune checkpoints, exemplified by the recently FDA-approved agent, Ipilimumab, an antibody that blocks the coinhibitory receptor CTLA-4. Capitalizing on the success of Ipilimumab, agents that target a second coinhibitory receptor, PD-1, or its ligand, PD-L1, are in clinical development. This section attempts to discuss recent progress of targeted agents and in tackling a more general target applicable to gastrointestinal cancer .

The use of immunosuppressive drugs in models of chronic rejection may limit their usefulness for mechanistic studies. We have developed a new minor histocompatibility-mismatched rat kidney transplant model without the need for immunosuppression. Kidneys from LEW (RT1(l)) donors were transplanted to congenic WF.1L (RT1(l)) recipients and compared with the reversed strain combination and isogenic controls. Urinary protein excretion was measured serially in all recipients; kidneys were harvested 90, 120, and 180 d after transplantation for morphologic analysis and cytokine gene expression. In vitro lymphocytic reactivity and cytokine analysis of mixed lymphocyte reaction (MLR) culture supernatants by ELISA was also carried out. LEW into WF.1L kidney grafts developed proteinuria starting 120 d after transplantation and were associated with morphologic changes of focal segmental glomerulosclerosis together with interstitial cell infiltrates, upregulated gene expression of IL-1beta, IL-2, and TNF-alpha/-beta, as well as IL-2, IFN-gamma, and TNF-alpha production by lymphocytes in MLR culture supernatants. WF.1L kidneys transplanted into LEW recipients did not develop chronic rejection and had upregulation of Th2 cytokines, both within the allograft and in MLR supernatant of recipient lymphocytes cultured with WF.1L cells. Furthermore, these lymphocytes produced both Th1 and Th2 cytokines when cultured with WF cells, unlike lymphocytes from the LEW isografts, which produced Th1 cytokines when challenged with WF cells. These studies show that indirect allorecognition can cause strain-dependent chronic rejection associated with Th1-like cytokine production, whereas production of Th2 cytokines is associated with protection from the development of chronic rejection.

Regulatory functions of alloreactive Th2 clones in human renal transplant recipients. Background Chronic allograft rejection is the major clinical problem in organ transplantation. There is evidence that indirect T cell recognition of donor-specific HLA peptides may play an important role in the immunopathogenesis of chronic allograft rejection. We have recently shown that HLA allopeptide-specific T cell clones generated from renal transplant recipients with chronic allograft nephropathy are of the Th1 phenotype, while those from stable patients are Th2. There is evidence in experimental animal models of autoimmunity and transplantation that Th2 cells may function to regulate immune responses, but the biological relevance of these observations in humans has not been reported. Methods The purpose of this study was to investigate the putative regulatory functions of alloreactive human Th2 clones. HLA-DR allopeptide-specific Th1 and Th2 cell clones were generated from peripheral blood lymphocytes of human renal allograft recipients with chronic allograft nephropathy (CAN) or with stable renal function (SRF), respectively. Results An in vitro co-culture system showed that the proliferative responses of Th1 clones from patients with CAN were significantly inhibited by the Th2 clones in response to the donor-derived HLA allopeptides. In addition, co-culture of the Th2 clones inhibited cytokine production (IFN-γ) by the Th1 clones in response to the donor-specific peptides. The regulatory functions of Th2 clones were antigen-specific since they only occurred when both the Th1 and Th2 clones were reactive to the same HLA-DR allopeptide, and were mediated by IL-4 and IL-10. Conclusions This is the first demonstration, to our knowledge, indicating that Th2 cells may function to regulate indirect Th1 alloimmune responses that are critical for the progression of CAN in humans.

Background: The Platelet derived growth factor (PDGF) and its receptors play a major role in inducing proliferation, migration, and angiogenesis by activating intracellular PI3K/Akt/mTOR signaling events in different solid tumors and therefore represent attractive targets in tumor therapy. Recently we showed a PDGF-induced activation of metabolism and proliferation in HT29 colon cancer cells in the absence of specific PDGF receptors. The aim of this study was to analyze PDGFR and VEGFR expression and possible alternative PDGF binding partners in colorectal cancer (CRC). Methods: Human HT29 colon cancer cells were cultured and stimulated with PDGF in a time-dependent manner. Additionally, VEGFR2 and EGFR inhibition was performed to analyze alternative PDGF signaling events. Whole cell or RNA extracts were analyzed by Western Blot and RT-q-PCR for receptors and PI3K/Akt/mTOR signaling. To investigate the effects of specific receptor inhibition on proliferation, MTS proliferation assays were performed. Moreover, mRNA levels of PDGFR and VEGFR in tumors from patients with CRC were analyzed by RT-qPCR. Results: Human UICC stage I-IV tumors exhibited a significantly increased PDGFRβ and VEGFR1,2 gene expression. As observed previously, HT29 colon cancer cells showed only positivity for VEGFR1,2, but no PDGFR protein expression. Despite that, stimulation with PDGF resulted in increased proliferation and metabolic changes. In contrast, Caco-2 and SW480 colon cancer cells showed PDGFR and VEGFR expression on protein level. Interestingly, PDGF stimulation increased VEGFR1 and 2 gene expression in HT29 colon cancer cells and secondly inhibition of VEGFR2 and EGFR showed alterations in proliferation and Akt signaling in PDGF stimulated cancer cells. Conclusion: Despite the absence of PDGF receptors in HT29 colon cancer cells, PDGF induced proliferating and metabolic effects in the tumor cells, suggesting an alternative binding partner on the tumor cell surface. Further investigation of the alternative PDGF binding partners could be of clinical relevance in CRC. Note: This abstract was not presented at the meeting. Citation Format: Romana Moench, Tanja Grimmig, Christoph-Thomas Germer, Ana Maria Waaga-Gasser, Martin Gasser. PDGF induces cell growth and changes in glucose metabolism in colon cancer in the absence of PDGF receptors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1237. doi:10.1158/1538-7445.AM2017-1237

Background: CD137L is expressed on antigen presenting cells and CD137/CD137L interaction co-stimulates activation and proliferation of CD137 expressing T cells. CD137L expression has also been detected on various cancer cells. While signaling in immune cells showed both inhibiting and activating effects the impact of CD137L induction on tumor cells is poorly understood. In this study, the expression of CD137 and CD137L and the effects of CD137L activation were analyzed in human colorectal cancer (CRC). Methods: Expression of CD137 and CD137L was examined in human colon cancer cell lines HT29, SW480 and SW620 treated with or without hypoxia using RT-qPCR, Western blot and FACS analysis. Its differentiated expression was further analyzed in human CRCs by immunofluorescent double-staining. To dissect the effects of CD137L activation on cancer cells, MTS proliferation assays were additionally performed. Results: All three human colon cancer cell lines demonstrated high cellular (FACS) and protein (Western Blot) CD137L expression. CD137 was found only in SW480 cells at weak expression. Additionally, both CD137 and CD137L were significantly upregulated in cells treated with hypoxia. In human CRCs both CD137 and CD137L expressing tumor cells were detected by immunofluorescent double-staining. Interestingly, activation of CD137L by immobilized CD137-Fc resulted in reduced cancer cell proliferation compared to IgG1-Fc controls. Conclusion: Our results demonstrate tumor cell mediated expression of the costimulatory molecule CD137 and its ligand CD137L in both colon cancer cell lines and human colorectal cancer. Moreover, CD137L reverse signaling was found to reduce cancer cell proliferation in vitro. Based on these data, the CD137/CD137L signaling pathway seems to present a promising target for cancer therapy in CRC. Note: This abstract was not presented at the meeting. Citation Format: Tanja Grimmig, Simone Callies, Hannes Naegele, Martin Wagner, Romana Moench, Buelent Polat, Christoph-Thomas Germer, Martin Gasser, Ana Maria Waaga-Gasser. Activation of CD137/CD137L results in reduced tumor cell proliferation in human colon cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5616. doi:10.1158/1538-7445.AM2017-5616

Purpose: Prostate specific antigen is not reliable in diagnosing prostate cancer (PCa), making the identification of novel, precise diagnostic biomarkers important. Since chemokines are associated with more aggressive disease and poor prognosis in diverse malignancies, we aimed to investigate the diagnostic relevance of chemokines in PCa. Materials and methods: Preoperative and early postoperative serum samples were obtained from 39 consecutive PCa patients undergoing radical prostatectomy. Serum from 15 healthy volunteers served as controls. Concentrations of CXCL12, CXCL13, CX3CL1, CCL2, CCL5, and CCL20 were measured in serum by Luminex. The expression activity of CXCR3, CXCR4, CXCR5, CXCR7, CXCL12, CXCL13, CX3CR1, CXCL1, CCR2, CCR5, CCR6, CCR7, CCL2, and CCL5 mRNA was assessed in tumor and adjacent normal tissue of prostatectomy specimens by quantitative real-time polymerase chain reaction. The associations of these chemokines with clinical and histological parameters were tested. Results: The gene expression activity of CCL2 and CCR6 was significantly higher in tumor tissue compared to adjacent normal tissue. CCL2 was also significantly higher in the blood samples of PCa patients, compared to controls. CCL5, CCL20, and CX3CL1 were lower in patient serum, compared to controls. CCR2 tissue mRNA was negatively correlated with the Gleason score and grading. Conclusion: Chemokines are significantly modified during tumorigenesis of PCa, and CCL2 is a promising diagnostic biomarker.

Toll like receptor (TLR) signaling has been suggested to play an important role in the inflammatory microenvironment of solid tumors and through this inflammation-mediated tumor growth. Here, we studied the role of tumor cells in their process of self-maintaining TLR expression independent of inflammatory cells and cytokine milieu for autoregulative tumor growth signaling in pancreatic cancer. We analyzed the expression of TLR2, -4, and -9 in primary human cancers and their impact on tumor growth via induced activation in several established pancreatic cancers. TLR-stimulated pancreatic cancer cells were specifically investigated for activated signaling pathways of VEGF/PDGF and anti-apoptotic Bcl-xL expression as well as tumor cell growth. The primary pancreatic cancers and cell lines expressed TLR2, -4, and -9. TLR-specific stimulation resulted in activated MAP-kinase signaling, most likely via autoregulative stimulation of demonstrated TLR-induced VEGF and PDGF expression. Moreover, TLR activation prompted the expression of Bcl-xL and has been demonstrated for the first time to induce tumor cell proliferation in pancreatic cancer. These findings strongly suggest that pancreatic cancer cells use specific Toll like receptor signaling to promote tumor cell proliferation and emphasize the particular role of TLR2, -4, and -9 in this autoregulative process of tumor cell activation and proliferation in pancreatic cancer.