Biology subjects

Puca, E.

Publications and source records attributed to Puca, E..

3 recordsLinked to original sources

bioRxiv2020

Immunotherapy with immunocytokines and PD-1 blockade enhances the anticancer activity of small molecule-drug conjugates targeting carbonic anhydrase IX

Small molecule-drug conjugates (SMDCs) represent an alternative to conventional antitumor chemotherapeutic agents, with the potential to improve the therapeutic window of cytotoxic payloads through active delivery at the site of the disease. In this article we describe novel combination therapies consisting of anti-Carbonic Anhydrase IX SMDCs combined with different immunomodulatory products. The therapeutic effect of the SMDCs was potentiated by combination with PD-1 blockade and with tumor-homing antibody-cytokine fusions in mouse models of renal cell carcinoma and colorectal cancer. The combination with L19-IL12, a fusion protein specific to the alternatively-spliced EDB domain of fibronectin containing the murine interleukin-12 moiety, was active also against large established tumors. Analysis of the microscopic structures of healthy organs performed three months after tumor eradication confirmed absence of pathological abnormalities in the healthy kidney, liver, lung, stomach and intestine. Our findings may be of clinical significance as they provide motivation for the development of combinations based on small molecule-drug conjugates and immunotherapy for the treatment of renal cell carcinoma and of hypoxic tumors.

cancer biology↗

bioRxiv2019

Comparative evaluation of bolus and fractionated administration modalities for two antibody-cytokine fusions in immunocompetent tumor-bearing mice

Antibody-cytokine fusion proteins are being considered as biopharmaceuticals for cancer immunotherapy. Tumor-homing cytokine fusions typically display an improved therapeutic activity compared to the corresponding unmodified cytokine products, but toxicity profiles at equivalent doses are similar, since side effects are mainly driven by the cytokine concentration in blood. In order to explore avenues to harness the therapeutic potential of antibody-cytokine fusions while decreasing potential toxicity, we compared bolus and fractionated administration modalities for two tumor-targeting antibody-cytokine fusion proteins based on human interleukin-2 (IL2) and murine tumor necrosis factor (TNF) (i.e., L19-hIL2 and L19-mTNF) in two murine immunocompetent mouse models of cancer (F9 and C51). A comparative quantitative biodistribution analysis with radio-labeled protein preparations revealed that a fractionated administration of L19-hIL2 could deliver comparable product doses to the tumor with decreased product concentration in blood and normal organs, compared to bolus injection. By contrast, L19-mTNF (a product that causes a selective vascular shutdown in the tumor) accumulated most efficiently after bolus injection. Fractionated schedules allowed the safe administration of a cumulative dose of L19-mTNF, which was 2.5-times higher than the lethal dose for bolus injection. Dose fractionation led to a prolonged tumor growth inhibition for F9 teratocarcinomas, but not for C51 colorectal tumors, which responded best to bolus injection. Thus, dose fractionation may have different outcomes for the same antibody-cytokine product in different biological contexts.

pharmacology and toxicology↗

bioRxiv2019

The antibody-based delivery of interleukin-12 to solid tumors boosts NK and CD8+ T cell activity and synergizes with immune check-point inhibitors

We describe the cloning and characterization of a novel fusion protein (termed L19-mIL12), consisting of murine interleukin-12 in single-chain format, sequentially fused to the L19 anti-body in tandem diabody format. The fusion protein bound avidly to the cognate antigen (the alternatively-spliced EDB domain of fibronectin), retained the activity of the parental cyto-kine and was able to selectively localize to murine tumors in vivo, as shown by quantitative biodistribution analysis. L19-mIL12 exhibited a potent anti-tumor activity in immunocompetent mice bearing CT26 carcinomas and WEHI-164 sarcomas, which could be boosted by combination with check-point blockade, leading to durable cancer eradication. L19-mIL12 also inhibited tumor growth in mice with Lewis lung carcinoma (LLC), but in this case cancer cures could not be obtained, both in monotherapy and in combination. A microscopic analysis and a depletion experiment of tumor-infiltrating leukocytes illustrated the contribution of NK cells and CD8+ T cells for the anti-cancer activity observed in both tumor models. Upon L19-mIL12 treatment, the density of regulatory T cells (Tregs) was strongly increased in LLC, but not in CT26 tumors. A FACS analysis also revealed that the majority of CD8+ T cells in CT26 tumors were specific to the retroviral AH1 antigen.\n\nNOVELTY AND IMPACT STATEMENTIn this study, we describe the generation of a novel fusion protein consisting of murine inter-leukin-12 fused to the L19 antibody (specific to the EDB domain of fibronectin). L19-mIL12 revealed favourable tumor to organ ratios 24h after intravenous administration and it was able to cure 60% of CT26 tumor-bearing mice. From a clinical perspective, the rapid clearance from circulation should ease the administration to patients as infusions could be stopped upon onset of side-effects.

cancer biology↗