Oncolytic Adenoviruses Armed with Tumor Necrosis Factor Alpha and Interleukin-2 Enable Successful Adoptive Cell Therapy

Adoptive cell therapy holds much promise in the treatment of cancer but results in solid tumors have been modest. The notable exception is tumor-infiltrating lymphocyte (TIL) therapy of melanoma, but this approach only works with high-dose preconditioning chemotherapy and systemic interleukin (IL)-2 postconditioning, both of which are associated with toxicities. To improve and broaden the applicability of adoptive cell transfer, we constructed oncolytic adenoviruses coding for human IL-2 (hIL2), tumor necrosis factor alpha (TNF-alpha), or both. The viruses showed potent antitumor efficacy against human tumors in immunocompromised severe combined immunodeficiency (SCID) mice. In immunocompetent Syrian hamsters, we combined the viruses with TIL transfer and were able to cure 100% of the animals. Cured animals were protected against tumor re-challenge, indicating a memory response. Arming with IL-2 and TNF-alpha increased the frequency of both CD4(+) and CD8(+) TILs in vivo and augmented splenocyte proliferation ex vivo, suggesting that the cytokines were important for T cell persistence and proliferation. Cytokine expression was limited to tumors and treatment-related signs of systemic toxicity were absent, suggesting safety. To conclude, cytokine-armed oncolytic adenoviruses enhanced adoptive cell therapy by favorable alteration of the tumor microenvironment. A clinical trial is in progress to study the utility of Ad5/3-E2F-d24-hTNFa-IRES-hIL2 (TILT-123) in human patients with cancer.Peer reviewe

Improving adenovirus-based immunotherapies for treatment of solid tumors

New treatment modalities are needed for patients with advanced cancer, who have undergone several unsuccessful pretreatments. Cancer immunotherapy has emerged as a promising field of medicine with the potential to induce durable responses in these patients. Within the immunotherapy field, a diverse set of approaches have been employed, all of which aim at combating tumors with the cells of the immune system. Oncolytic immunotherapy encompasses the use of genetically engineered viruses to specifically kill (lyse) tumor cells and, importantly, to induce an antitumor immune response in the process. Oncolytic adenoviruses in particular possess an excellent safety profile and can be armed with immunostimulatory transgenes for the enhancement of antitumor immunity. In the first part of the thesis, oncolytic adenovirus armed with granulocyte-macrophage colony-stimulating factor (GMCSF) was used together with the chemotherapeutic agents doxorubicin and ifosfamide to treat soft-tissue sarcoma (STS) in an adenovirus-permissive Syrian hamster model. The combination treatment was highly effective against syngeneic hamster leiomyosarcoma tumors in vivo, with indications that adenovirus replication was improved in the presence of doxorubicin and that oncolytic adenovirus/chemotherapy combination induced immunogenic cell death (ICD) of tumor cells. Tumor-infiltrating lymphocytes (TIL) from syngeneic Syrian hamster tumors were cultured, characterized and used therapeutically with oncolytic adenovirus in the second part of the thesis. Co-treatment of pancreatic cancer tumors with adoptive transfer of pancreatic cancer derived TIL and oncolytic adenovirus resulted in improved antitumor efficacy when compared with either monotherapy. In the third part, non-replicating adenovirus vectors coding for the murine cytokines tumor necrosis factor alpha (TNFa) and interleukin 2 (IL-2) were constructed and used in combination with adoptive transfer of tumor-specific T-cell receptor engineered (TCR) T-cells for the treatment of immunosuppressive melanoma. This combination showed significant antitumor efficacy over single agent treatments. Mechanistic studies revealed that intratumoral virus injections induce trafficking of adoptively transferred T-cells to tumors. Furthermore, the cytokine-coding adenoviruses caused favorable alterations in the tumor microenvironment. In the final part of the thesis, oncolytic adenoviruses coding for human versions of TNFa and IL-2 were used with hamster TIL to successfully treat pancreatic cancer tumors. In fact, virus injections were capable of eliminating most tumors when combined TIL transfer, and protected cured hamsters from tumor rechallenge. From a safety perspective it is noteworthy that virus-mediated cytokine production was restricted to tumors, as negligible levels of cytokines were observed in the sera of intratumorally injected animals. In conclusion, the combinatorial approach studied in the preclinical setting here represents a rational and effective solution for the treatment of advanced solid tumors, warranting the clinical translation of adenovirus-based immunotherapy combined with other immunotherapies.Levinneen syövän uusista hoitokeinoista lupaavimpia on syövän immunoterapia. Tässä terapiamuodossa elimistön immuunisolut aktivoidaan hyökkäämään syöpäkasvaimia vastaan. Onkolyyttinen (syöpäsoluja hajottava) immunoterapia käsittää geneettisesti muokattujen virusten käytön tähän tarkoitukseen. Erityisesti adenovirukset ovat lupaavia, sillä niiden turvallisuusprofiili on erinomainen ja niiden genomiin voidaan lisätä immuunivastetta stimuloivia transgeenejä. Väitöskirjatutkimuksen ensimmäisessä osatyössä tutkittiin kemoterapian ja onkolyyttisen adenoviruksen yhdistelmiä pehmytkudossarkoomien hoitoon prekliinisissä eläinmalleissa. Yhdistelmähoidon havaittiin estävän tehokkaasti ihonalaisten syöpäkasvaimien kasvua eläimissä ilman vakavia sivuvaikutuksia. Lisääntyneen tehokkuuden taustalla havaittiin olevan kaksi mekanismia: immunogeenisen solukuoleman ja adenoviruksen replikaation tehostuminen kemoterapian läsnäollessa. Toisessa osatyössä tutkittiin onkolyyttisen viroterapian ja adoptiivisen T-solusiirron yhdistämistä kultahamstereissa (Mesocricetus auratus). Ihmisen adenovirukset voivat replikoitua hamsterin kudoksissa (toisin kuin hiiren tai rotan), minkä vuoksi hamsteri on hyödyllinen prekliininen eläinmalli tutkittaessa onkolyyttisiä adenoviruksia. Hamsterin haimasyöpäkasvaimista eristetyt ja monistetut T-solut annettiin takaisin kasvaimia kantaneille hamstereille yhdessä adenovirushoidon kanssa; yhdistelmähoito oli tehokkaampi kuin T-soluhoito tai adenovirushoito yksinään. Melanooman hoitoa adenoviruksilla ja adoptiivisella T-solusiirrolla tutkittiin väitöskirjan kolmannessa osatyössä. Hiirimalleissa havaittiin, että immuunivastetta stimuloivia sytokiinejä (TNFa ja IL-2) koodaavat adenovirusvektorit tehostivat T-solusiirtoa kun viruksia injektoitiin melanoomakasvaimiin. Kuvantamiskokeissa todettiin, että radioaktiivisesti leimatut kasvainspesifiset T-solut kulkeutuivat tehokkaimmin kasvaimiin, joihin oli injektoitu molempia sytokiinejä koodaavia adenoviruksia. Lisäksi adenovirushoidon havaittiin muokkaavan kasvaimen mikroympäristöä T-solusiirteelle suotuisammaksi, toisin sanoen vähemmän immunosuppressiiviseksi. Neljännessä osatyössä rakennettiin ihmisen kudoksissa aktiivisia sytokiinejä koodaava onkolyyttinen adenovirus. Uusi virus tehosti T-soluhoitoa hamsterimallissa merkittävästi; yhdistelmähoito paransi suuren osan kasvaimia kantaneista hamstereista ja tuotti niille immuniteetin kasvaintyyppiä vastaan. Väitöskirjatyön tulokset tukevat adenovirushoidon yhdistämistä muihin syövän hoitomuotoihin. Tutkimukset luovat pohjan kliinisten kokeiden suunnitellulle potilaissa, joiden levinneeseen syöpään ei ole muita hoitokeinoja

Nuoruus sosiaalisena sopimuksena - suomalaisen nuorisotutkimuksen virstanpylväs

Kirja-arvostelu: Nuorisokulttuureista kulttuuriseen nuoruuteen. Tommi Hoikkal

Kiihtelysvaaran tapaus

Summary : The social meaning of alcohol - the Kiihtelysvaara case

Cytokine-Coding Oncolytic Adenovirus TILT-123 Is Safe, Selective, and Effective as a Single Agent and in Combination with Immune Checkpoint Inhibitor Anti-PD-1

Oncolytic viruses provide a biologically multi-faceted treatment option for patients who cannot be cured with currently available treatment options. We constructed an oncolytic adenovirus, TILT-123, to support T-cell therapies and immune checkpoint inhibitors in solid tumors. Adenoviruses are immunogenic by nature, are easy to produce in large quantities, and can carry relatively large transgenes. They are the most commonly used gene therapy vectors and are well tolerated in patients. TILT-123 expresses two potent cytokines, tumor necrosis factor alpha and interleukin-2, to stimulate especially the T-cell compartment in the tumor microenvironment. Before entering clinical studies, the safety and biodistribution of TILT-123 was studied in Syrian hamsters and in mice. The results show that TILT-123 is safe in animals as monotherapy and in combination with an immune checkpoint inhibitor anti-PD-1. The virus treatment induces acute changes in circulating immune cell compartments, but the levels return to normal by the middle of the treatment period. The virus is rapidly cleared from healthy tissues, and it does not cause damage to vital organs. The results support the initiation of a phase 1 dose-escalation trial, where melanoma patients receiving a tumor-infiltrating lymphocyte therapy are treated with TILT-123 (NCT04217473).Peer reviewe

Adenovirus Coding for Interleukin-2 and Tumor Necrosis Factor Alpha Replaces Lymphodepleting Chemotherapy in Adoptive T Cell Therapy

Lymphodepleting preconditioning with high-dose chemotherapy is commonly used to increase the clinical efficacy of adoptive T cell therapy (ACT) strategies, however, with severe toxicity for patients. Conversely, oncolytic adenoviruses are safe and, when engineered to express interleukin-2 (IL-2) and tumor necrosis factor alpha (TNF-alpha), they can achieve antitumor immunomodulatory effects similar to lymphodepletion. Therefore, we compare the safety and efficacy of such adenoviruses with a cyclophosphamide-and fludarabine- containing lymphodepleting regimen in the setting of ACT. Human adenovirus (Ad5/3-E2F-D24-hTNF-alpha-IRES-hIL-2; TILT-123) replication was studied using a Syrian hamster pancreatic tumor model (HapT1) infused with tumor- infiltrating lymphocytes (TILs). Using the oncolytic virus instead of lymphodepletion resulted in superior efficacy and survival. Immune cells responsive to TNF-alpha IL-2 were studied using an immunocompetent mouse melanoma model (B16. OVA) infused with ovalbumin-specific T (OT-I) cells. Here, the adenovirus approach improved tumor control together with increased intratumoral Th1 cytokine levels and infiltration of CD8+ T cells and CD86+ dendritic cells. Similar to humans, lymphodepleting preconditioning caused severe cytopenias, systemic inflammation, and damage to vital organs. Toxicity was minimal in adenovirus- and OT-Itreated mice. These findings demonstrate that ACT can be effectively facilitated by cytokine-coding adenovirus without requiring lymphodepletion, a rationale being clinically investigated.Peer reviewe