Cancer Immunoediting from Immunosurveillance to Tumor Escape in Microvillus-Formed Niche: A Study of Syngeneic Orthotopic Rat Bladder Cancer Model in Comparison with Human Bladder Cancer1

Cancer cells can develop an attenuated immunogenicity and/or create an immunosuppressive microenvironment to prevent tumor eradication by host immune system, the so-called “cancer immunoediting” hypothesis. The aim of the present study was to find evidence for this hypothesis by using a rat orthotopic bladder cancer model. Fisher rats were inoculated with AY-27 cells (a Fisher rat bladder cancer cell line). Cultured cancer cells, rat and human bladder cancer tissues, and publicly available microarray data from human bladder cancer were analyzed by means of bioinformatics and morphology. Results showed that 12 of 24 differentially expressed pathways were concordant in connection to cell cycle and proliferation between rats and humans (both non-muscle-invasive and muscle-invasive tumors) and that 11 of the 24 pathways, including major histocompatibility complex, were related to host immunosurveillance with activations of T cells and natural killer cells in rats. The altered pathways and morphogenesis of this rat model corresponded more closely with those of human muscle-invasive rather than non-muscle-invasive tumors. A unique ultrastructure displaying microvillus-formed niches was found in small areas within the tumor of both rats and humans. These niches were interconnected with desmosomes between cancer cells and without infiltration of lymphocytes. The expression of E-cadherin, selectins, PGP9.5, vascular endothelial growth factor, caspase-3, CD133, Oct-4, nestin, CD3, and CD45RA was lower in the tumor than in the adjacent normal epithelium. We suggest that the microvillus-formed niche that harbors a few implanted cancer cells might be the compartment that prevents the tumor eradication by the host immune system

Increased Anticancer Efficacy of Intravesical Mitomycin C Therapy when combined with a PCNA Targeting Peptide

Non–muscle-invasive bladder cancers (NMIBCs) are tumors confined to the mucosa or the mucosa/submucosa. An important challenge in treatment of NMIBC is both high recurrence and high progression rates. Consequently, more efficacious intravesical treatment regimes are in demand. Inhibition of the cell’s DNA repair systems is a new promising strategy to improve cancer therapy, and proliferating cell nuclear antigen (PCNA) is a new promising target. PCNA is an essential scaffold protein in multiple cellular processes including DNA replication and repair. More than 200 proteins, many involved in stress responses, interact with PCNA through the AlkB homologue 2 PCNA-interacting motif (APIM), including several proteins directly or indirectly involved in repair of DNA interstrand crosslinks (ICLs). In this study, we targeted PCNA with a novel peptide drug containing the APIM sequence, ATX- 101, to inhibit repair of the DNA damage introduced by the chemotherapeutics. A bladder cancer cell panel and two different orthotopic models of bladder cancer in rats, the AY-27 implantation model and the dietary BBN induction model, were applied. ATX-101 increased the anticancer efficacy of the ICL-inducing drug mitomycin C (MMC), as well as bleomycin and gemcitabine in all bladder cancer cell lines tested. Furthermore, we found that ATX-101 given intravesically in combination with MMC penetrated the bladder wall and further reduced the tumor growth in both the slow growing endogenously induced and the rapidly growing transplanted tumors. These results suggest that ATX-101 has the potential to improve the efficacy of current MMC treatment in NMIBC

Increased Anticancer Efficacy of Intravesical Mitomycin C Therapy when Combined with a PCNA Targeting Peptide

Non–muscle-invasive bladder cancers (NMIBCs) are tumors confined to the mucosa or the mucosa/submucosa. An important challenge in treatment of NMIBC is both high recurrence and high progression rates. Consequently, more efficacious intravesical treatment regimes are in demand. Inhibition of the cell’s DNA repair systems is a new promising strategy to improve cancer therapy, and proliferating cell nuclear antigen (PCNA) is a new promising target. PCNA is an essential scaffold protein in multiple cellular processes including DNA replication and repair. More than 200 proteins, many involved in stress responses, interact with PCNA through the AlkB homologue 2 PCNA-interacting motif (APIM), including several proteins directly or indirectly involved in repair of DNA interstrand crosslinks (ICLs). In this study, we targeted PCNA with a novel peptide drug containing the APIM sequence, ATX-101, to inhibit repair of the DNA damage introduced by the chemotherapeutics. A bladder cancer cell panel and two different orthotopic models of bladder cancer in rats, the AY-27 implantation model and the dietary BBN induction model, were applied. ATX-101 increased the anticancer efficacy of the ICL-inducing drug mitomycin C (MMC), as well as bleomycin and gemcitabine in all bladder cancer cell lines tested. Furthermore, we found that ATX-101 given intravesically in combination with MMC penetrated the bladder wall and further reduced the tumor growth in both the slow growing endogenously induced and the rapidly growing transplanted tumors. These results suggest that ATX-101 has the potential to improve the efficacy of current MMC treatment in NMIBC

Chondrosarcoma in Norway 1990-2013; an epidemiological and prognostic observational study of a complete national cohort

Background: Knowledge of chondrosarcoma (CS) of bone to date is based on institutional reports and registry publications with limits in reporting, detail and quality of data. Method: We have performed a retrospective search of CS of bone in the National Cancer Registry in Norway from 1990-2013, cross checked against local tumor databases with further quality control and supplementation of all data from clinical files. The time period is defined by the routine use of axial imaging in clinical practice. 311 cases are included. We performed 108 pathological reviews and 223 radiological reviews. The manuscript is prepared according to the STROBE checklist for strengthening of observational studies. We perform uni-/multivariate cox analysis to define independent prognostic variables from the main cohort of central CS of bone. Results: The incidence of CS of bone in Norway is 2.85/million/yr. for both sexes overall, rising to 3.45/million/yr. in the last 5 year period. There is an increase in the most common central CS subtype, stronger for women than for men. Central CS has, in general 10-15% local recurrence rates, all evident by 5 years while metastasis rate increases with location and grade. Exceptions are extremity grade 1 CS which displayed no metastatic events and axial grade 3 disease with high rates (50%) of both local and metastatic relapse. Peripheral CS has limited metastatic potential (2%) but rates of local relapse (13%) continue to appear towards 10 years of follow up. Malignancy grade 3 independently predicts rate of metastasis and presence of soft tissue component predicts local recurrence, metastasis and survival. Conclusion: Rates of local recurrence, metastasis and disease specific survival follow clear patterns depending on subtype, location and grade allowing better tailoring of follow up regimes. Malignancy grade 3 and presence of a soft tissue component independently predict behaviour for central CS of bone

Chondrosarcoma in Norway 1990-2013; an epidemiological and prognostic observational study of a complete national cohort

Background: Knowledge of chondrosarcoma (CS) of bone to date is based on institutional reports and registry publications with limits in reporting, detail and quality of data. Method: We have performed a retrospective search of CS of bone in the National Cancer Registry in Norway from 1990–2013, cross checked against local tumor databases with further quality control and supplementation of all data from clinical files. The time period is defined by the routine use of axial imaging in clinical practice. A total of 311 cases are included. We performed 108 pathological reviews and 223 radiological reviews. The manuscript was prepared according to the STROBE checklist for strengthening of observational studies. We performed uni-/multivariate cox analyses to define independent prognostic variables from the main cohort of central CS of bone. Results: The incidence of CS of bone in Norway is 2.85/million/yr. for both sexes overall, rising to 3.45/million/yr. in the last 5-year period. There is an increase in the most common central CS subtype, stronger for women than for men. Central CS had, in general 10–15% local recurrence rates, all evident by 5 years while metastasis rate increases with location and grade. Exceptions are extremity grade 1 CS which displayed no metastatic events and axial grade-3 disease with high rates (50%) of both local and metastatic relapse. Peripheral CS had limited metastatic potential (2%), but rates of local relapse (13%) continue to appear towards 10 years of follow up. Malignancy grade 3 independently predicts rate of metastasis and presence of soft tissue component predicts local recurrence, metastasis and survival. Conclusion: Rates of local recurrence, metastasis and disease specific survival follow clear patterns depending on subtype, location and grade allowing better tailoring of follow-up regimes. Malignancy grade 3 and the presence of a soft tissue component independently predict behavior for central CS of bone

Immunohistochemical evidence for an impairment of autophagy in tumorigenesis of gastric carcinoids and adenocarcinomas in rodent models and patients

Background/Aim: Autophagy has dual roles in tumorigenesis: tumor-promoting or tumorsuppressing. The aim of the present study was to examine autophagy-related markers by immunohistochemistry in gastric carcinoids and adenocarcinomas in rodent models and patients. Methods: Gastric carcinoids in Mastomys were induced by loxtidine treatment. Spontaneously developed gastric adenocarcinomas in Japanese cotton rats and INS-GAS transgenic mice were included. Patient tissue samples of gastric carcinoids or adenocarcinomas were collected. Immunohistochemistry was performed against autophagy-related gene protein-6 (ATG-6, also called beclin-1), ATG-5 and ATG-16. Results: In tumor-free Mastomys, ATG-5, ATG-16 and beclin-1 were immunepositive in the gastric mucosa. In tumor-bearing Mastomys, ATG-5 and ATG-16 were negative in the tumors, whereas beclin-1 was positive in four of five animals. In carcinoid patients, ATG-5 was negative in six of ten, ATG-16 negative in nine of ten, and beclin-1 negative in three of ten patients. In cotton rats, ATG-5 and ATG-16 were negative in all tumors. Beclin-1 was negative in three of five rats. In INS-GAS mice, ATG-5 and beclin-1 were positive in the tumor area, but the numbers of immunopositive cells per gland were reduced by about 50% in comparison with wildtype mice. In adenocarcinoma patients, ATG-5 and ATG-16 were negative in eight of ten, and beclin-1 positive in all ten patients. Conclusions: An impaired autophagy took place at the stage of formation of ATG-5-ATG-12-ATG-16 complex in both gastric carcinoids and adenocarcinoma of both rodent models and patients. ATG-5 and ATG-16 might be better markers than beclin-1 in assessing autophagy in these lesions

Spermine and citrate as metabolic biomarkers for assessing prostate cancer aggressiveness.

Separating indolent from aggressive prostate cancer is an important clinical challenge for identifying patients eligible for active surveillance, thereby reducing the risk of overtreatment. The purpose of this study was to assess prostate cancer aggressiveness by metabolic profiling of prostatectomy tissue and to identify specific metabolites as biomarkers for aggressiveness. Prostate tissue samples (n = 158, 48 patients) with a high cancer content (mean: 61.8%) were obtained using a new harvesting method, and metabolic profiles of samples representing different Gleason scores (GS) were acquired by high resolution magic angle spinning magnetic resonance spectroscopy (HR-MAS). Multivariate analysis (PLS, PLS-DA) and absolute quantification (LCModel) were used to examine the ability to predict cancer aggressiveness by comparing low grade (GS = 6, n = 30) and high grade (GS≥7, n = 81) cancer with normal adjacent tissue (n = 47). High grade cancer tissue was distinguished from low grade cancer tissue by decreased concentrations of spermine (p = 0.0044) and citrate (p = 7.73·10(-4)), and an increase in the clinically applied (total choline+creatine+polyamines)/citrate (CCP/C) ratio (p = 2.17·10(-4)). The metabolic profiles were significantly correlated to the GS obtained from each tissue sample (r = 0.71), and cancer tissue could be distinguished from normal tissue with sensitivity 86.9% and specificity 85.2%. Overall, our findings show that metabolic profiling can separate aggressive from indolent prostate cancer. This holds promise for the benefit of applying in vivo magnetic resonance spectroscopy (MRS) within clinical MR imaging investigations, and HR-MAS analysis of transrectal ultrasound-guided biopsies has a potential as an additional diagnostic tool

"Two hits - one stone" increased efficacy of cisplatin-based therapies by targeting PCNA's role in both DNA repair and cellular signaling

Low response rate and rapid development of resistance against commonly used chemotherapeutic regimes demand new multi-targeting anti-cancer strategies. In this study, we target the stress-related roles of the scaffold protein PCNA with a cell-penetrating peptide containing the PCNA-interacting motif APIM. The APIM-peptide increased the efficacy of cisplatin-based therapies in a muscle-invasive bladder cancer (MIBC) solid tumor model in rat and in bladder cancer (BC) cell lines. By combining multiple omics-levels, from gene expression to proteome/kinome and metabolome, we revealed a unique downregulation of the EGFR/ERBB2 and PI3K/Akt/mTOR pathways in the APIM-peptide-cisplatin combination treated cells. Additionally, the combination treatment reduced the expression of anti-apoptotic proteins and proteins involved in development of resistance to cisplatin. Concurrently, we observed increased levels of DNA breaks in combination treated cells, suggesting that the APIM-peptide impaired PCNA - DNA repair protein interactions and reduced the efficacy of repair. This was also seen in cisplatin-resistant cells, which notably was re-sensitized to cisplatin by the APIM-peptide. Our data indicate that the increased efficacy of cisplatin treatment is mediated both via downregulation of known oncogenic signaling pathways and inhibition of DNA repair/translesion synthesis (TLS), thus the APIM-peptide hits both nuclear and cytosolic functions of PCNA. The novel multi-targeting strategy of the APIM-peptide could potentially improve the efficacy of chemotherapeutic regiments for treatment of MIBC, and likely other solid tumors.publishedVersionCopyright: Søgaard et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Presence of TMPRSS2-ERG is associated with alterations of the metabolic profile in human prostate cancer

TMPRSS2-ERG has been proposed to be a prognostic marker for prostate cancer. The aim of this study was to identify changes in metabolism, genes and biochemical recurrence related to TMPRSS2-ERG by using an integrated approach, combining metabolomics, transcriptomics, histopathology and clinical data in a cohort of 129 human prostate samples (41 patients). Metabolic analyses revealed lower concentrations of citrate and spermine comparing ERGhigh to ERGlow samples, suggesting an increased cancer aggressiveness of ERGhigh compared to ERGlow. These results could be validated in a separate cohort, consisting of 40 samples (40 patients), and magnetic resonance spectroscopy imaging (MRSI) indicated an in vivo translational potential. Alterations of gene expression levels associated with key enzymes in the metabolism of citrate and polyamines were in consistence with the metabolic results. Furthermore, the metabolic alterations between ERGhigh and ERGlow were more pronounced in low Gleason samples than in high Gleason samples, suggesting it as a potential tool for risk stratification. However, no significant difference in biochemical recurrence was detected, although a trend towards significance was detected for low Gleason samples. Using an integrated approach, this study suggests TMPRSS2-ERG as a potential risk stratification tool for inclusion of active surveillance patients