Evaluation of the anti-cancer efficacy of lipid nanoparticles containing siRNA against HPV16 E6/E7 combined with cisplatin in a xenograft model of cervical cancer

PLoS One. 2024 Feb 16;19(2):e0298815. doi: 10.1371/journal.pone.0298815. eCollection 2024.

Abstract

Objective: To investigate the anti-cancer efficacy of ENB101-LNP, an ionizable lipid nanoparticles (LNPs) encapsulating siRNA against E6/E7 of HPV 16, in combination therapy with cisplatin in cervical cancer in vitro and in vivo.

Methods: CaSki cells were treated with ENB101-LNP, cisplatin, or combination. Cell viability assessed the cytotoxicity of the treatment. HPV16 E6/E7 gene knockdown was verified with RT-PCR both in vitro and in vivo. HLA class I and PD-L1 were checked by flow cytometry. A xenograft model was made using CaSki cells in BALB/c nude mice. To evaluate anticancer efficacy, mice were grouped. ENB101-LNP was given three times weekly for 3 weeks intravenously, and cisplatin was given once weekly intraperitoneally. Tumor growth was monitored. On day 25, mice were euthanized; tumors were collected, weighed, and imaged. Tumor samples were analyzed through histopathology, immunostaining, and western blot.

Results: ENB101-LNP and cisplatin synergistically inhibit CaSki cell growth. The combination reduces HPV 16 E6/E7 mRNA and boosts p21 mRNA, p53, p21, and HLA class I proteins. In mice, the treatment significantly blocked tumor growth and promoted apoptosis. Tumor inhibition rates were 29.7% (1 mpk ENB101-LNP), 29.6% (3 mpk), 34.0% (cisplatin), 47.0% (1 mpk ENB101-LNP-cisplatin), and 68.8% (3 mpk ENB101-LNP-cisplatin). RT-PCR confirmed up to 80% knockdown of HPV16 E6/E7 in the ENB101-LNP groups. Immunohistochemistry revealed increased p53, p21, and HLA-A expression with ENB101-LNP treatments, alone or combined.

Conclusion: The combination of ENB101-LNP, which inhibits E6/E7 of HPV 16, with cisplatin, demonstrated significant anticancer activity in the xenograft mouse model of cervical cancer.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cisplatin / pharmacology
  • Cisplatin / therapeutic use
  • Female
  • Heterografts
  • Human papillomavirus 16 / genetics
  • Human papillomavirus 16 / metabolism
  • Humans
  • Liposomes*
  • Mice
  • Mice, Nude
  • Nanoparticles*
  • Oncogene Proteins, Viral* / genetics
  • Oncogene Proteins, Viral* / metabolism
  • Papillomavirus E7 Proteins / genetics
  • Papillomavirus E7 Proteins / metabolism
  • RNA, Messenger / genetics
  • RNA, Small Interfering / genetics
  • Tumor Suppressor Protein p53 / genetics
  • Uterine Cervical Neoplasms* / drug therapy
  • Uterine Cervical Neoplasms* / genetics
  • Uterine Cervical Neoplasms* / pathology

Substances

  • RNA, Small Interfering
  • Cisplatin
  • Lipid Nanoparticles
  • Tumor Suppressor Protein p53
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • RNA, Messenger
  • Liposomes

Grants and funding

This research was supported by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI20C1586). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.