1. Safety and efficacy of IL-12 plasmid DNA transfection into pig skin : supportive data for human clinical trials on gene therapy and vaccinationUrša Lampreht Tratar, Tanja Jesenko, Maša Omerzel, Alenka Seliškar, Urban Stupan, Mihajlo Djokić, Jerneja Sredenšek, Blaž Trotovšek, Gregor Serša, Maja Čemažar, 2024, original scientific article Abstract: Gene electrotransfer (GET) of plasmids encoding interleukin 12 (IL-12) has already been used for the treatment of various types of tumors in human oncology and as an adjuvant in DNA vaccines. In recent years, we have developed a plasmid encoding human IL-12 (phIL12) that is currently in a phase I clinical study. The aim was to confirm the results of a non-clinical study in mice on pharmacokinetic characteristics and safety in a porcine model that better resembled human skin. The GET of phIL12 in the skin was performed on nine pigs using different concentrations of plasmid phIL12 and invasive (needle) or noninvasive (plate) types of electrodes. The results of our study demonstrate that the GET of phIL-12 with needle electrodes induced the highest expression of IL-12 at the protein level on day 7 after the procedure. The plasmid was distributed to all tested organs; however, its amount decreased over time and was at a minimum 28 days after GET. Based on plasmid copy number and expression results, together with blood analysis, we showed that IL-12 GET is safe in a porcine animal model. Furthermore, we demonstrated that pigs are a valuable model for human gene therapy safety studies.
Keywords: interleukin 12, gene electrotransfer, immunotherapy
Published in DiRROS: 18.04.2024; Views: 19; Downloads: 13
 Full text (16,83 MB)
This document has many files! More... |
2. Adjuvant TNF-a therapy to electrochemotherapy with intravenous cisplatin in murine sarcoma exerts synergistic antitumor effectivenessMaja Čemažar, Vesna Todorović, Janez Ščančar, Urša Lampreht Tratar, Monika Savarin, Urška Kamenšek, Simona Kranjc Brezar, Andrej Cör, Gregor Serša, 2015, original scientific article Abstract: Background. Electrochemotherapy is a tumour ablation modality, based on electroporation of the cell membrane, allowing non-permeant anticancer drugs to enter the cell, thus augmenting their cytotoxicity by orders of magnitude. In preclinical studies, bleomycin and cisplatin proved to be the most suitable for clinical use. Intravenous administration of cisplatin for electrochemotherapy is still not widely accepted in the clinics, presumably due to its lower antitumor effectiveness, but adjuvant therapy by immunomodulatory or vascular-targeting agents could provide a way for its potentiation. Hence, the aim of the present study was to explore the possibility of adjuvant tumour necrosis factor % (TNF-%) therapy to potentiate antitumor effectiveness of electrochemotherapy with intravenous cisplatin administration in murine sarcoma. Materials and methods. In vivo study was designed to evaluate the effect of TNF-% applied before or after the electrochemotherapy and to evaluate the effect of adjuvant TNF-% on electrochemotherapy with different cisplatin doses. Results. A synergistic interaction between TNF-% and electrochemotherapy was observed. Administration of TNF-% before the electrochemotherapy resulted in longer tumour growth delay and increased tumour curability, and was significantly more effective than TNF-% administration after the electrochemotherapy. Tumour analysis revealed increased platinum content in tumours, TNF-% induced blood vessel damage and increased tumour necrosis after combination of TNF-% and electrochemotherapy, indicating an anti-vascular action of TNF-%. In addition, immunomodulatory effect might have contributed to curability rate of the tumours. Conclusion. Adjuvant intratumoural TNF-% therapy synergistically contributes to electrochemotherapy with intravenous cisplatin administration. Due to its potentiation at all doses of cisplatin, the combined treatment is predicted to be effective also in tumours, where the drug concentration is suboptimal or in bigger tumours, where electrochemotherapy with intravenous cisplatin is not expected to be sufficiently effective.
Keywords: electrochemotherapy, TNF, adjuvant immunotherapy, cisplatin
Published in DiRROS: 17.04.2024; Views: 51; Downloads: 7
Full text (978,26 KB) |
3. Gene immunotherapy of colon carcinoma with IL-2 and IL-12 using gene electrotransferTilen Komel, Maša Omerzel, Urška Kamenšek, Katarina Žnidar, Urša Lampreht Tratar, Simona Kranjc Brezar, Klemen Dolinar, Sergej Pirkmajer, Gregor Serša, Maja Čemažar, 2023, original scientific article Abstract: Gene immunotherapy has become an important approach in the treatment of cancer. One example is the introduction of genes encoding immunostimulatory cytokines, such as interleukin 2 and interleukin 12, which stimulate immune cells in tumours. The aim of our study was to determine the effects of gene electrotransfer of plasmids encoding interleukin 2 and interleukin 12 individually and in combination in the CT26 murine colon carcinoma cell line in mice. In the in vitro experiment, the pulse protocol that resulted in the highest expression of IL-2 and IL-12 mRNA and proteins was used for the in vivo part. In vivo, tumour growth delay and also complete response were observed in the group treated with the plasmid combination. Compared to the control group, the highest levels of various immunostimulatory cytokines and increased immune infiltration were observed in the combination group. Long-term anti-tumour immunity was observed in the combination group after tumour re-challenge. In conclusion, our combination therapy efficiently eradicated CT26 colon carcinoma in mice and also generated strong anti-tumour immune memory.
Keywords: colon carcinoma, gene electrotransfer, gene immunotherapy
Published in DiRROS: 21.03.2024; Views: 95; Downloads: 48
Full text (6,92 MB)
This document has many files! More... |
4. The prognostic and predictive value of human gastrointestinal microbiome and exosomal mRNA expression of PD-L1 and IFNγ for immune checkpoint inhibitors response in metastatic melanoma patients : protocol trialAna Erman, Marija Ignjatović, Katja Leskovšek, Simona Miceska, Urša Lampreht Tratar, Maša Omerzel, Veronika Kloboves-Prevodnik, Maja Čemažar, Lidija Kandolf Sekulović, Gorazd Avguštin, Janja Ocvirk, Tanja Mesti, 2023, original scientific article Abstract: Background: Immunotherapy has been successful in treating advanced melanoma, but a large proportion of patients do not respond to the treatment with immune checkpoint inhibitors (ICIs). Preclinical and small cohort studies suggest gastrointestinal microbiome composition and exosomal mRNA expression of PD-L1 and IFNγ from the primary tumor, stool and body fluids as potential biomarkers for response. Methods: Patients treated with immune checkpoint inhibitors as a first line treatment for metastatic melanoma are recruted to this prospective study. Stool samples are submitted before the start of treatment, at the 12th (+/−2) week and 28th (+/−2) week, and at the occurrence of event (suspected disease progression/hyperprogression, immune-related adverse event (irAE), deterioration). Peripheral venous blood samples are taken additionally at the same time points for cytologic and molecular tests. Histological material from the tumor tissue is obtained before the start of immunotherapy treatment. Primary objectives are to determine whether the human gastrointestinal microbiome (bacterial and viral) and the exosomal mRNA expression of PD-L1 and IFNγ and its dynamics predicts the response to treatment with PD-1 and CTLA-4 inhibitors and its association with the occurrence of irAE. The response is evaluated radiologically with imaging methods in accordance with the irRECIST criteria. Conclusions: This is the first study to combine and investigate multiple potential predictive and prognostic biomarkers and their dynamics in first line ICI in metastatic melanoma patients.
Keywords: gastrointestinal microbiome, mRNA expression of PD-L1 and IFNγ, immune checkpoint inhibitors, metastatic melanoma
Published in DiRROS: 21.03.2024; Views: 71; Downloads: 36
Full text (642,09 KB)
This document has many files! More... |
5. 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: 540; Downloads: 282
Full text (9,70 MB)
This document has many files! More... |
6. Genska terapija v onkologiji, prvi razvojni koraki v SlovenijiMaja Čemažar, Tanja Jesenko, Maša Omerzel, Boštjan Markelc, Urška Kamenšek, Simona Kranjc Brezar, Špela Kos, Urša Lampreht Tratar, Katarina Žnidar, Andrej Renčelj, Urška Matkovič, Teja Valant, Kristina Levpušček, Živa Modic, Tilen Komel, Tim Božič, Urša Kešar, Barbara Starešinič, Katja Uršič Valentinuzzi, Monika Savarin, Primož Strojan, Gorana Gašljević, Maja Ota, Aleš Grošelj, Črt Jamšek, Rosana Hudej, Matjaž Peterka, Franc Smrekar, Barbara Hubad, Marjan Hosta, Jaka Kužnik, Alojz Hosta, Damijan Miklavčič, Matej Reberšek, Aleksandra Cvetkoska, Anja Zajc, Janja Dermol-Černe, Nataša Tozon, Nina Milevoj, Alenka Nemec Svete, Gregor Serša, 2022, professional article Abstract: Genska terapija postaja čedalje bolj zanimiva tudi v onkologiji. Med aplikacijami je morda najzanimivejša imunostimulacija. Pripravimo lahko plazmidno DNA, ki nosi zapis za različne imunostimulatorne molekule, ki jih vnesemo v celice tumorjev ali normalnih tkiv. Ta tkiva postanejo proizvajalci teh molekul, ki lahko delujejo lokalno ali pa se izločajo tudi sistemsko v krvni obtok. Ker plazmidna DNA ne prehaja celične membrane, so potrebni dostavni sistemi, virusni ali nevirusni. V naših študijah uporabljamo predvsem nevirusni dostavni sistem – elektroporacijo. Interlevkin 12 (IL-12) je eden od zanimivih citokinov, za katerega je znano protitumorsko delovanje s spodbujanjem imunskega odziva in antiangiogenim delovanjem. Namen projekta SmartGene.si je bil pripraviti plazmid z zapisom za interlevkin 12 (plazmid phIL12) in pripraviti vse potrebno za njegovo klinično testiranje za zdravljenje kožnih tumorjev. V konzorciju smo združili moči s partnerji z akademskega in industrijskega področja. Treba je bilo pripraviti plazmid za uporabo v humani onkologiji po zahtevah Evropske agencije za zdravila (EMA). Za prijavo klinične študije na Javno agencijo za zdravila in medicinske pripomočke (JAZMP) smo morali izvesti tudi vse neklinične raziskave o varnosti in učinkovitosti zdravila. Nato je bilo treba razviti postopek priprave zdravila, zagotoviti primerne prostore za pripravo in izvedbo postopka priprave zdravila. V treh letih smo dosegli vse te zastavljene cilje in dobili dovoljenje za izvajanje klinične študije na kožnih tumorjih, ki ga je izdala JAZMP na osnovi pozitivnega mnenja Komisije Republike Slovenije za medicinsko etiko. Zdaj poteka klinična študija faze I preizkušanja plazmida phIL12 na kožnih tumorjih glave in vratu z namenom preveriti varnost in sprejemljivost genskega elektroprenosa plazmida v tumorje. Cilj študije je prav tako določiti primeren odmerek zdravila, ki bi ga v nadaljnji klinični študiji uporabili kot adjuvantno zdravljenje k ablativnim terapijam, kot sta radioterapija ali elektrokemoterapija.
Keywords: genska terapija, interlevkin-12, plazmidna DNA, elektroprenos genov, rak kože
Published in DiRROS: 01.07.2022; Views: 1166; Downloads: 233
Full text (420,40 KB) |
7. Razvoj avtologne tumorske vakcine pripravljene z obsevanjemTinkara Remic, Gregor Serša, Katja Uršič Valentinuzzi, Kristina Levpušček, Urša Lampreht Tratar, Maja Čemažar, Urška Kamenšek, 2022, published scientific conference contribution abstract Keywords: onkološka cepiva, tumorski antigeni, eksperimentalna onkologija
Published in DiRROS: 17.06.2022; Views: 618; Downloads: 183
Full text (80,69 KB) |
8. |
