Retinoic acid-loaded PLGA nanocarriers targeting cell cholesterol potentialize the antitumour effect of PD-L1 antibody by preventing epithelial-mesenchymal transition mediated by M2-TAM in colorectal cancer

Raimundo Fernandes de Araújo Júnior; George A Lira; Timo Schomann; Rômulo S Cavalcante; Natalia Feitosa Vilar; Regina Célia Monteiro de Paula; Raelle Ferreira Gomes; Chih Kit Chung; Carla Jorquera-Cordero; Olena Vepris; Alan B Chan; Luis J Cruz

doi:10.1016/j.tranon.2023.101647

Retinoic acid-loaded PLGA nanocarriers targeting cell cholesterol potentialize the antitumour effect of PD-L1 antibody by preventing epithelial-mesenchymal transition mediated by M2-TAM in colorectal cancer

Transl Oncol. 2023 May:31:101647. doi: 10.1016/j.tranon.2023.101647. Epub 2023 Feb 27.

Affiliations

¹ Cancer and Inflammation Research Laboratory, Department of Morphology, Federal University of Rio Grande do Norte Natal, RN 59072-970, Brazil; Post-Graduation Programme in Structural and Functional Biology, Federal University of Rio Grande do Norte, Natal, RN 59072-970, Brazil; Post-Graduation Programme in Health Science, Federal University of Rio Grande do Norte, Natal, RN 59072-970, Brazil; Percuros B.V., Leiden, CL 2333, the Netherlands; Translational Nanobiomaterials and Imaging, Department of Radiology, Leiden University Medical Center, Leiden, ZA 2333, the Netherlands. Electronic address: fernandes.araujo@ufrn.br.
² Cancer and Inflammation Research Laboratory, Department of Morphology, Federal University of Rio Grande do Norte Natal, RN 59072-970, Brazil; Post-Graduation Programme in Health Science, Federal University of Rio Grande do Norte, Natal, RN 59072-970, Brazil; Translational Nanobiomaterials and Imaging, Department of Radiology, Leiden University Medical Center, Leiden, ZA 2333, the Netherlands; League Against Cancer from Rio Grande do Norte, Advanced Oncology Center, Natal 59075-740, Brazil.
³ Percuros B.V., Leiden, CL 2333, the Netherlands; Translational Nanobiomaterials and Imaging, Department of Radiology, Leiden University Medical Center, Leiden, ZA 2333, the Netherlands.
⁴ Cancer and Inflammation Research Laboratory, Department of Morphology, Federal University of Rio Grande do Norte Natal, RN 59072-970, Brazil; Post-Graduation Programme in Health Science, Federal University of Rio Grande do Norte, Natal, RN 59072-970, Brazil.
⁵ Cancer and Inflammation Research Laboratory, Department of Morphology, Federal University of Rio Grande do Norte Natal, RN 59072-970, Brazil.
⁶ Post-Graduation Programme in Chemistry, Federal University of Ceará, Fortaleza, CE 60440-900, Brazil.
⁷ Percuros B.V., Leiden, CL 2333, the Netherlands; Translational Nanobiomaterials and Imaging, Department of Radiology, Leiden University Medical Center, Leiden, ZA 2333, the Netherlands; JeNaCell GmbH, Winzerlaer Straße 2, Jena 07745, Germany.
⁸ Percuros B.V., Leiden, CL 2333, the Netherlands; Department of Orthopedics, University Medical Center Utrecht, Heidelberglaan 100, Utrecht, CX 3584, the Netherlands.
⁹ Translational Nanobiomaterials and Imaging, Department of Radiology, Leiden University Medical Center, Leiden, ZA 2333, the Netherlands.
¹⁰ Percuros B.V., Leiden, CL 2333, the Netherlands.

Abstract

Tumour-associated macrophages (TAMs) often promote cancer progression through immunosuppression in the tumour microenvironment (TME). However, the signalling pathways crosstalk responsible for this mechanism remain unclear. The aim of our study was to investigate whether the interaction between TAMs and colorectal cancer cells could be down-regulated by nanoparticles (NPs) loaded with retinoic acid (RA) and coated with cholesterol (CHO), in combination with an anti-PD-L1 immune checkpoint inhibitor. Tumours were evaluated by qRT-PCR and immunohistochemistry from allographic tumour growth model. In addition, human tumours were evaluated by Tissue Microarray (TMA) and immunohistochemistry. Complementary analysis of epithelial-mesenchymal transition, cell migration, and macrophage polarisation were evaluated in vitro. We showed that the IL-10R/IL-10 axis is involved in overstimulation of the STAT3 pathway as well as downregulation of the NF-κB signalling pathway, which supports a loop of immunosuppressive cytokines that induces the M2-TAM phenotype. Furthermore, our combined findings suggest that the upregulation of STAT3/NF-κB pathways crosstalk mediated by immunosuppressive cytokines, such as IL-10/PD-L1/TGF-β, via M2-TAMs in the TME, leads to immunosuppression and epithelial-mesenchymal-transition of the colorectal cancer for stimulating Vimentin, CXCL12 and CD163 in the primary tumours. Importantly, NPs holding RA and coated with CHO in combination with anti-PD-L1 were more efficient in blocking this signalling pathway. These results contribute to our understanding of the immunological mechanisms, especially the re-educating of TAMs, and provide a novel management strategy for aggressive colorectal cancers using anti-PD-L1-conjugated nanocarriers.

Keywords: Anti-PD-L1; Immunomodulation; M2-like macrophages; Metastasis; PLGA nanoparticles; STAT3/NF-κB; Tumour microenvironment.