Silver Nanoparticles (AgNPs) Uptake by Caveolae-Dependent Endocytosis is Responsible for Their Selective Effect Towards Castration Resistant Prostate Cancer

Mariana Morais; Francisca Dias; Patrícia Figueiredo; Inês Tavares; Carla Escudeiro; Manuel R Teixeira; Alexandra Teixeira; Johnny Lisboa; Kirsi S Mikkonen; Ana L Teixeira; Rui Medeiros

doi:10.2147/IJN.S447645

Silver Nanoparticles (AgNPs) Uptake by Caveolae-Dependent Endocytosis is Responsible for Their Selective Effect Towards Castration Resistant Prostate Cancer

Int J Nanomedicine. 2024 Sep 5:19:9091-9107. doi: 10.2147/IJN.S447645. eCollection 2024.

Authors

Mariana Morais^{1

2}, Francisca Dias¹, Patrícia Figueiredo³, Inês Tavares^{1

2}, Carla Escudeiro^{4

5}, Manuel R Teixeira^{2

4

5}, Alexandra Teixeira⁶, Johnny Lisboa⁶, Kirsi S Mikkonen^{3

7}, Ana L Teixeira¹, Rui Medeiros^{1

2

8

9

10}

Affiliations

¹ Molecular Oncology and Viral Pathology Group, Research Center of IPO Porto (CI-IPOP) / RISE@CI-IPOP (Health Research Network), Portuguese Oncology Institute of Porto (IPO Porto) / Porto Comprehensive Cancer Center (Porto.ccc), Porto, Portugal.
² ICBAS, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Porto, Portugal.
³ Department of Food and Nutrition, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland.
⁴ Department of Laboratory Genetics, Portuguese Oncology Institute of Porto (IPO-Porto)/Porto Comprehensive Cancer Center, Porto, Portugal.
⁵ Cancer Genetics Group, IPO-Porto Research Center(CI-IPOP)/RISE@CI-IPOP (Health Research Network), Portuguese Oncology Institute of Porto (IPO-Porto)/Porto Comprehensive Cancer Center, Porto, Portugal.
⁶ Fish Immunology and Vaccinology, i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.
⁷ Helsinki Institute of Sustainability Science (HELSUS), University of Helsinki, Helsinki, Finland.
⁸ Biomedical Research Center (CEBIMED, Faculty of Health Sciences, Fernando Pessoa University (UFP), Porto, Portugal.
⁹ Research Department, LPCC- Portuguese League Against Cancer (Nrnorte), Porto, Portugal.
¹⁰ Faculty of Medicine, University of Porto (FMUP), University of Porto, Porto, Portugal.

Abstract

Purpose: Castration Resistant Prostate Cancer (CRPC) is characterized by poor prognosis and limited therapeutic options. AgNPs functionalized with glucose (G-AgNPs) were observed cytotoxic to CRPC cell lines (PC-3 and Du-145) and not LNCaP. This study aims to evaluate AgNPs and G-AgNPs' uptake mechanisms in these cells and understand their role in the selective effect against CRPC cells.

Methods: Uptake of AgNPs and G-AgNPs was assessed through transmission electron microscopy (TEM). A microRNA (miRNAs) analysis approach was used to uncover the main molecular differences responsible for the endocytic mechanisms' regulation. Caveolin (Cav) 1 and 2 mRNA and protein levels were assessed in the three cell lines. Caveolae-dependent endocytosis was inhibited with genistein or siCav1^- and siCav2^- in PC-3 and Du-145 and resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration. Caveolae-dependent endocytosis was induced with Cav1⁺ and Cav2⁺ plasmids in LNCaP, resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration and TEM to assess their location.

Results: AgNPs and G-AgNPs were not uptaked by LNCaP. miRNA analysis revealed 37 upregulated and 90 downregulated miRNAs. Functional enrichment analysis of miRNAs' targets resulted in enrichment of terms related to endocytosis and caveolae. We observed that Cav1 and Cav2 are not expressed in LNCaP. Inhibiting caveolae-dependent endocytosis in Du-145 and PC-3 led to a significative reduction of cytotoxic capacity of AgNPs and G-AgNPs and induction of caveolae-dependent endocytosis in LNCaP lead to a significative increase as well as their uptake by cells.

Conclusion: This study shows the potential of these AgNPs as a new therapeutic approach directed to CRPC patients, uncovers caveolae-dependent endocytosis as the uptake mechanism of these AgNPs and highlights deregulation of Cav1 and Cav2 expression as a key difference in hormone sensitive and resistant PCa cells which may be responsible for drug resistance.

Keywords: caveolins; endocytosis; prostate cancer resistant to castration; silver nanoparticles; uptake mechanism.

MeSH terms

Antineoplastic Agents / pharmacology
Caveolae* / drug effects
Caveolae* / metabolism
Caveolin 1* / genetics
Caveolin 1* / metabolism
Caveolin 2 / genetics
Caveolin 2 / metabolism
Cell Line, Tumor
Cell Survival / drug effects
Endocytosis* / drug effects
Endocytosis* / physiology
Humans
Male
Metal Nanoparticles* / chemistry
MicroRNAs* / genetics
MicroRNAs* / metabolism
PC-3 Cells
Prostatic Neoplasms, Castration-Resistant* / metabolism
Silver* / chemistry
Silver* / pharmacokinetics
Silver* / pharmacology

Substances

Silver
Caveolin 1
MicroRNAs
CAV1 protein, human
Caveolin 2
CAV2 protein, human
Antineoplastic Agents

Grants and funding

This work is part of the project “P.CCC: Centro Compreensivo de Cancro do Porto” - NORTE-01-0145-FEDER-072678, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). MM is funded by FCT through the grant 2020.08193.BD and FD is funded by UIDP/00776/2020-4B.