San Raffaele Telethon Institute for Gene Therapy

Targeted Cancer Gene Therapy


Head of Unit

Luigi Naldini


Immunotherapy has gained renewed interest for cancer treatment thanks to the efficacy of immune checkpoint blockers and adoptive therapy with genetically engineered T cells. However, many patients still fail to respond or develop resistance mainly because of an immunosuppressive tumor microenvironment (TME). We are developing strategies for gene-based and tumor-targeted delivery of immunostimulating cytokines with the goal of achieving stable therapeutic activity selectively at the tumor site while sparing other organs from exposure-related toxicity and preventing systemic or local counter-regulatory responses. By this approach we can reprogram the TME towards immune activation and elicit protective immunity against the tumor and its metastases.


Associated Research Unit: Gene Transfer Technologies and New Gene Therapy Strategies

Research activity

Leveraging on our experience with both ex vivo and in vivo gene delivery, we are pursuing this research with two different platforms, which are being developed thanks to research efforts in two areas:

  1. Reprogramming the TME by ex vivo genetically engineered tumor-infiltrating monocytes. Building on our original description of a population of tumor-associated macrophages (TAM) expressing the TIE2 receptor (TEMs) and exerting pro-tumoral functions, we have provided proof-of-principle of a new cell and gene therapy approach exploiting these cells to deliver interferon alpha (IFN-a) to tumors. Transplant of hematopoietic stem and progenitor cells (HSPC) engineered with lentiviral vectors (LV) expressing IFNa under the transcriptional control of the TIE2 gene enhancer/promoter and post-transcriptional regulation by miRNA-126 enables selective release of the cytokine in the TME by the HSPC TAM progeny, inducing robust tumor responses in several experimental tumor models.  We showed effective reprogramming of the immune suppressive TME, leading to enhanced recruitment, activation and effector function of immune cells, which in turn induced tumor inhibition and protective immunity against multiple tumor-associated antigens, both in a leukemia and a glioblastoma model. The latter strategy has been brought to first-of-its-kind and first-in-human testing for the treatment of high-grade glioblastoma in collaboration with our spinoff Genenta Science, with preliminary but encouraging data on feasibility, safety and biological efficacy. More recently, we have developed a second-generation gene delivery platform, allowing switching On and Off cytokine secretion at the disease site and further advancing its specificity, applied it to both IFNa and IL-12, and showed synergistic therapeutic activity with checkpoint blockade or CAR-T cell therapy in mouse tumor models.
  2. In vivo gene-based targeted cytokine delivery to liver metastases by engineered lentiviral vectors. Colorectal (CRC) and pancreatic ductal adenocarcinomas (PDAC) are among the most common causes of cancer death, which is primarily due to liver metastatic (LMS) disease. Immune responses against CRC and PDAC LMS are limited by the immunosuppressive TME of the liver. To overcome this limitation, we are designing novel interventions aimed at reprogramming the LMS TME enabling protective immune responses against multiple tumor antigens. We have shown that IFNa delivery by TAM, born out of ex vivo engineered HSPC, can limit growth of several types of tumors in mouse models, including CRC LMS. Building on this observation and our studies of in vivo administration of immune-stealth LV to small and large animal models, we have developed a new LV-based in vivo gene delivery platform to rapidly convey the expression of IFNa to liver resident macrophages (Kupffer cells) and TAM in CRC LMS. LV-based delivery resulted in sustained and robust cytokine expression preferentially in areas surrounding LMS while limiting toxicity in other tissues, delaying tumor progression and leading to tumor clearance in some treated mice. Spatial transcriptomic and single cell omics show that tumor inhibition was associated with increased innate and adaptive immune activation. Altogether, in vivo gene-based delivery of IFNa to LMS could constitute an innovative therapeutic tool in the treatment of metastatic CRC and PDAC.