181. PARP inhibitor olaparib has a potential to increase the effectiveness of electrochemotherapy in BRCA1 mutated breast cancer in miceMaša Omerzel, Tanja Jesenko, Boštjan Markelc, Larisa Janžič, Maja Čemažar, Gregor Serša, 2021, original scientific article Abstract: Electrochemotherapy (ECT), a local therapy, has different effectiveness among tumor types. In breast can-cer, its effectiveness is low; therefore, combined therapies are needed. The aim of our study was to com-bine ECT with PARP inhibitor olaparib, which could inhibit the repair of bleomycin or cisplatin inducedDNA damage and potentiate the effectiveness of ECT. The effects of combined therapy were studied inBRCA1mutated (HCC1937) and non-mutated (HCC1143) triple negative breast cancer cell lines.Therapeutic effectiveness was studied in 2D and 3D cell cultures andin vivoon subcutaneousHCC1937 tumor model in mice. The underlying mechanism of combined therapy was determined withthe evaluation ofcH2AX foci. Combined therapy of ECT with bleomycin and olaparib potentiated theeffectiveness of ECT inBRCA1mutated HCC1937, but not in non-mutated HCC1143 cells. The combinedtherapy had a synergistic effect, which was due to the increased number of DNA double strand breaks.Addition of olaparib to ECT with bleomycinin vivoin HCC1937 tumor model had only minimal effect,indicating repetitive olaparib treatment would be needed. This study demonstrates that DNA repar inhibiting drugs, like olaparib, have the potential to increase the effectiveness of ECT with bleomycin. Keywords: electrochemotherapy, breast cancer, olaparib, bleomycin Published in DiRROS: 21.09.2022; Views: 580; Downloads: 199 Full text (3,74 MB) |
182. Mutational burden, MHC-I expression and immune infiltration as limiting factors for in situ vaccination by TNF[alfa] and IL-12 gene electrotransferUrška Kamenšek, Katja Uršič Valentinuzzi, Boštjan Markelc, Maja Čemažar, Vita Šetrajčič Dragoš, Gregor Serša, 2021, original scientific article Abstract: In situ vaccination is a promising immunotherapeutic approach, where various local ablative therapies are used to induce an immune response against tumor antigens that are released from the therapy-killed tumor cells. We recently proposed using intratumoral gene electrotransfer for concomitant transfection of a cytotoxic cytokine tumor necrosis factor-% (TNF%) to induce in situ vaccination, and an immunostimulatory cytokine interleukin 12 (IL-12) to boost the primed immune response. Here, our aim was to test the local and systemic effectiveness of the approach in tree syngeneic mouse tumor models and associate it with tumor immune profiles, characterized by tumor mutational burden, immune infiltration and expression of PD-L1 and MHC-I on tumor cells. While none of the tested characteristic proved predictive for local effectiveness, high tumor mutational burden, immune infiltration and MHC-I expression were associated with higher abscopal effectiveness. Hence, we have confirmed that both the abundance and presentation of tumor antigens as well as the absence of immunosuppressive mechanisms are important for effective in situ vaccination. These findings provide important indications for future development of in situ vaccination based treatments, and for the selection of tumor types that will most likely benefit from it. Keywords: in situ vaccination, gene electrotransfer, interleukin 12, tumor necrosis factor [alfa] Published in DiRROS: 19.09.2022; Views: 604; Downloads: 197 Full text (1,78 MB) |
183. Gene electrotransfer of proinflammatory chemokines CCL5 and CCL17 as a novel approach of modifying cytokine expression profile in the tumor microenvironmentTim Božič, Gregor Serša, Simona Kranjc Brezar, Maja Čemažar, Boštjan Markelc, 2021, original scientific article Abstract: The effectiveness of immunotherapy highly correlates with the degree and the type of infiltrated immune cells in the tumor tissue. Treatments based on modifying the immune cell infiltrate of the tumor microenvironment are thus gaining momentum. Therefore, the aim of our study was to investigate the effects of gene therapy with two proinflammatory chemokines CCL5 and CCL17 on inflammatory cytokine expression profile and immune cell infiltrate in two murine breast tumor models, 4T1 and E0771, and two murine colon tumor models, CT26 and MC38. In vitro, lipofection of plasmid DNA encoding CCL5 or CCL17 resulted in changes in the cytokine expression profile similar to control plasmid DNA, implying that the main driver of these changes was the entry of foreign DNA into the cell%s cytosol. In vivo, gene electrotransfer resulted in high expression levels of both Ccl5 and Ccl17 transgenes in the 4T1 and CT26 tumor models. Besides a minor increase in the survival of the treated mice, the therapy also resulted in increased expression of Cxcl9 and Ifn%, potent activators of the immune system, in CT26 tumors. However, this was not recapitulated in changes of TME, implying that a further refinement of the dosing schedule is needed. Keywords: chemokines, cytokine expression, gene electrotransfer, CCL5 Published in DiRROS: 19.09.2022; Views: 618; Downloads: 176 Full text (5,63 MB) |
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185. Tumor cell-based vaccine contributes to local tumor irradiation by eliciting a tumor model-dependent systemic immune responseTinkara Remic, Gregor Serša, Kristina Levpušček, Urša Lampreht Tratar, Katja Uršič Valentinuzzi, Andrej Cör, Urška Kamenšek, 2022, original scientific article Abstract: Multimodal treatment approaches, such as radio-immunotherapy, necessitate regimen optimization and the investigation of the interactions of different modalities. The aim of this study was two-fold. Firstly, to select the most effective combination of irradiation and the previously developed tumor cell-based vaccine and then to provide insight into the immune response to the selected combinatorial treatment. The study was performed in immunologically different murine tumor models: B16F10 melanoma and CT26 colorectal carcinoma. The most effective combinatorial treatment was selected by comparing three different IR regimens and three different vaccination regimens. We determined the local immune response by investigating immune cell infiltration at the vaccination site and in tumors. Lastly, we determined the systemic immune response by investigating the amount of tumor-specific effector lymphocytes in draining lymph nodes. The selected most effective combinatorial treatment was 5× 5 Gy in combination with concomitant single-dose vaccination (B16F10) or with concomitant multi-dose vaccination (CT26). The combinatorial treatment successfully elicited a local immune response at the vaccination site and in tumors in both tumor models. It also resulted in the highest amount of tumor-specific effector lymphocytes in draining lymph nodes in the B16F10, but not in the CT26 tumor-bearing mice. However, the amount of tumor-specific effector lymphocytes was intrinsically higher in the CT26 than in the B16F10 tumor model. Upon the selection of the most effective combinatorial treatment, we demonstrated that the vaccine elicits an immune response and contributes to the antitumor efficacy of tumor irradiation. However, this interaction is multi-faceted and appears to be dependent on the tumor immunogenicity. Keywords: experimental oncology, multimodal treatment, radio-imunotherapy Published in DiRROS: 14.09.2022; Views: 635; Downloads: 319 Full text (9,70 MB) This document has many files! More... |
186. Estimating quantitative physiological and morphological tissue parameters of murine tumor models using hyperspectral imaging and optical profilometryTadej Tomanič, Luka Rogelj, Jošt Stergar, Boštjan Markelc, Tim Božič, Simona Kranjc Brezar, Gregor Serša, Matija Milanič, 2022, original scientific article Abstract: Understanding tumors and their micro-environment are essential for successfuland accurate disease diagnosis. Tissuephysiology and morphology are altered intumors compared to healthy tissues, andthere is a need to monitor tumors and their surrounding tissues, includingblood vessels, non-invasively. This preliminary study utilizes a multimodaloptical imaging system combining hyperspectral imaging (HSI) and three-dimensional (3D) optical profilometry (OP) to capture hyperspectral imagesand surface shapes of subcutaneously grown murine tumor models. Hyper-spectral images are corrected with 3D OP data and analyzed using the inverse-adding doubling (IAD) method to extract tissue properties such as melaninvolume fraction and oxygenation. Blood vessels are segmented using theB-COSFIRE algorithm from oxygenation maps. From 3D OP data, tumor vol-umes are calculated and compared to manual measurements using a verniercaliper. Results show that tumors can be distinguished from healthy tissuebased on most extracted tissue parameters (p<0:05). Furthermore, blood oxy-genation is 50% higher within the blood vessels than in the surrounding tissue,and tumor volumes calculated using 3D OP agree within 26% with manualmeasurements using a vernier caliper. Results suggest that combining HSI andOP could provide relevant quantitative information about tumors and improvethe disease diagnosis. Keywords: medical physics, hyperspectral imaging, diffuse reflectance spectroscopy, blood vessels, tumors Published in DiRROS: 08.09.2022; Views: 613; Downloads: 203 Full text (3,79 MB) |
187. Non-clinical in vitro evaluation of antibiotic resistance gene-free plasmids encoding human or murine IL-12 intended for first-in-human clinical studyŠpela Kos, Maša Omerzel, Tanja Jesenko, Boštjan Markelc, Urška Kamenšek, Katarina Žnidar, Urška Matkovič, Andrej Renčelj, Gregor Serša, Rosana Hudej, Aneja Tuljak, Matjaž Peterka, Maja Čemažar, 2021, original scientific article Abstract: Interleukin 12 (IL-12) is a key cytokine that mediates antitumor activity of immune cells. To fulfill its clinical potential, the development is focused on localized delivery systems, such as gene electrotransfer, which can provide localized delivery of IL-12 to the tumor microenvironment. Gene electrotransfer of the plasmid encoding human IL-12 is already in clinical trials in USA, demonstrating positive results in the treatment of melanoma patients. To comply with EU regulatory requirements for clinical application, which recommend the use of antibiotic resistance gene-free plasmids, we constructed and developed the production process for the clinical grade quality antibiotic resistance gene-free plasmid encoding human IL-12 (p21-hIL-12-ORT) and its ortholog encoding murine IL-12 (p21-mIL-12-ORT). To demonstrate the suitability of the p21-hIL-12-ORT or p21-mIL-12-ORT plasmid for the first-in-human clinical trial, the biological activity of the expressed transgene, its level of expression and plasmid copy number were determined in vitro in the human squamous cell carcinoma cell line FaDu and the murine colon carcinoma cell line CT26. The results of the non-clinical evaluation in vitro set the basis for further in vivo testing and evaluation of antitumor activity of therapeutic molecules in murine models as well as provide crucial data for further clinical trials of the constructed antibiotic resistance gene-free plasmid in humans. Keywords: interleukin 12, gene electrotransfer, antibiotic resistance, plasmids Published in DiRROS: 07.09.2022; Views: 584; Downloads: 318 Full text (4,73 MB) This document has many files! More... |
188. Influence of housing conditions on reliability of immunocastration and consequences for growth performance of male pigsKevin Kress, Ulrike Weiler, Sonja Schmucker, Marjeta Čandek-Potokar, Milka Vrecl, Gregor Fazarinc, Martin Škrlep, Nina Batorek Lukač, Volker Stefanski, 2020, original scientific article Abstract: Immunocastration is a sustainable alternative to piglet castration but faces limited market acceptance. The phenomenon of non-responders has not to date been examined in detail, but adverse and stressful housing conditions (e.g., mixing of groups) might impair the success of vaccinations. Therefore, we evaluated the influence of housing conditions on the immune response after two Improvac® vaccinations at an age of 12 and 22 weeks, respectively. Boars, immunocastrates and barrows (n = 48 each) were assigned to three different housing conditions (n = 36 enriched, n = 36 standard n = 72 repeated social mixing). Immune response was quantified by measuring GnRH-binding and its consequences for testosterone concentrations, development of the genital tract and boar taint. Growth performance was evaluated via average daily gain (ADG). GnRH-binding and testosterone levels revealed that immunocastration reliably suppressed testicular functions after the 2nd vaccination. Housing conditions did not modify testicular function but influenced ADG as animals under mixing grew slower than those under enriched conditions. Gonadal status had only a slight impact on ADG except in immunocastrates, which showed a temporarily higher ADG after the 2nd vaccination. The results show that immunocastration is a reliable procedure under different housing conditions and competitive in terms of growth performance. Keywords: immunocastration, vaccination, Improvac, non-responder, immune response, housing conditions, surgical castration, boar taint, growth performance, genital tract Published in DiRROS: 06.09.2022; Views: 734; Downloads: 254 Link to full text |
189. Priročnik za prepoznavanje tujerodnih drevesnih vrst v alpskem prostoruAjša Alagić, Bénédicte Baxerres, Frédéric Berger, Anja M. Bindewald, Sylvain Bouquet, Giuseppe Brundu, Debojyoti Chakraborty, Patricia Detry, Freya-Isabel Georges, Quentin Guillory, Janez Kermavnar, Lado Kutnar, Katharina Lapin, Aleksander Marinšek, Eric Mermin, Anja Müller-Meißner, Janine Oettel, Anica Simčič, Simon Zidar, 2022, dictionary, encyclopaedia, lexicon, manual, atlas, map Keywords: tujerodne drevesne vrste, Alpe, invazivne drevesne vrste Published in DiRROS: 12.08.2022; Views: 1442; Downloads: 468 Full text (19,49 MB) |
190. Identification handbook for non native tree species in the Alpine spaceAjša Alagić, Bénédicte Baxerres, Frédéric Berger, Anja M. Bindewald, Sylvain Bouquet, Giuseppe Brundu, Debojyoti Chakraborty, Patricia Detry, Freya-Isabel Georges, Quentin Guillory, Janez Kermavnar, Lado Kutnar, Katharina Lapin, Aleksander Marinšek, Eric Mermin, Anja Müller-Meißner, Janine Oettel, Anica Simčič, Simon Zidar, 2022, dictionary, encyclopaedia, lexicon, manual, atlas, map Keywords: non-native tree species, Alps, invasive alien species Published in DiRROS: 12.08.2022; Views: 683; Downloads: 240 Full text (17,57 MB) |