(T1430-07-43) Sandwiched Nanofiber Sheets and Hybrid Gel for Localized and Prolonged Management of Cervical Cancer

Purpose: Existing therapeutic modalities for cervical cancer are generally resistant to chemotherapy and have limited drug access to locally diseased targets. Curcumin (CUR), an extremely hydrophobic herbal drug is backed by evidences for cervical cancer therapy. In the current study, the problem is addressed using CUR-Supramolecular Complex (CUR-SMC) delivered to the diseased vaginal tissues via hybrid gel (HG) and sandwiched nanofiber sheets (SNFS) for localized intravaginal delivery and prolonged drug action.

Methods: Existing therapeutic modalities for cervical cancer are generally resistant to chemotherapy and have limited drug access to locally diseased targets. Curcumin (CUR), an extremely hydrophobic herbal drug is backed by evidences for cervical cancer therapy. In the current study, the problem is addressed using CUR-Supramolecular Complex (CUR-SMC) delivered to the diseased vaginal tissues via hybrid gel (HG) and sandwiched nanofiber sheets (SNFS) for localized intravaginal delivery and prolonged drug action.

Results: The phase solubility of CUR-SMC was linear (A_L-Linear type) indicating formation of soluble complex at 1:1 molar ratio of the host and guest molecule. In silico modeling studies showed that the hydrophobic aromatic ring of CUR was deeply inserted inside the CD cavity with binding energy of -84.98 kcal/mol and docking score -3.792. MD studies revealed the mean RMSD value indicates higher stability of the CUR-CD complex value lies in 2.0 A˚ indicating the host and guest had no positional change and structural deformation. The formulated in situ HG displayed remarkable characteristics conducive to effective vaginal drug delivery. Its rapid gelation upon reaching body temperature, solidifying within seconds ( < 150 sec), underscores its potential for immediate action upon application. The maintenance of pH within the acceptable range of ~4.40 for vaginal application ensures compatibility with the physiological environment. Furthermore, the substantial increase in viscosity at body temperature indicates the gel's sol-gel transition property, enhancing its efficacy and providing sustained release of therapeutic agents. Notably, the HG demonstrated robust mucoadhesive properties, enabling prolonged retention (nearly 10 h, via X-Ray Imaging) within the vaginal cavity and enhancing drug delivery and therapeutic efficacy. Spectral characterization showed the successful complexation due to the disappearance of characteristic peaks of CUR at 3510.45 cm^-1(phenolic O-H) and 1616.35 cm^-1>(benzene ring),and the thermal characterization analysis indicated that CUR sharp endothermic peak at 177.54 ˚C disappeared indicating complex formation which was in line with the SEM micrographs showing a smooth and uniform surface of the SNFS. Mucoadhesion strength of blank, CUR-SMC loaded HG and SNFS were ~15, 22 and 23 g and the negative region of graph was an indication of the adhesion of SNFS. The content and release of CUR from the SNFS were ~13 mg/ 50 mg of nanofiber with ~65% release and 75 % release with HG at the end of 24 h. The HG and SNFS showed no vascular lysis or haemorrhage ex vivo, and found biocompatible with red blood cells (Hemolysis < 5%). CUR-SMC loaded HG and SNFS manifested a decrease in cell viability and pristine CUR-SMC solution showed significantly lower cell death. Inhibitory concentration (IC50) values of free CUR, HG and SNFS in cells were ~60, 50 and 35 µg/mL respectively. Accelerated stability studies showed no significant changes (p > 0.05) in the physicochemical features and drug content of the gels and SNFS. The histopathological studies confirmed the non-irritancy of the HG and SNFS on the vaginal mucosa with intact squamous epithelium. The administered HG and SNFS showed longer residence (10 h) in vagina as confirmed by in vivo studies and confocal studies showed a penetration of ~100 µm with rhodamine dye solution, ~200 µm with HG and ~240 µm with SNFS shows the capability of reaching drug to target cancer tissues without systemic toxicity.

Conclusion: The developed CUR-SMC as HG and SNFS is a promising and safe herbal treatment modality and can ensure longer residence in the vagina and provides a favourable approach for developing intravaginal delivery systems for cervical cancer treatment.

References: 1. Burmeister CA, Khan SF, Schäfer G, Mbatani N, Adams T, Moodley J, et al. Cervical cancer therapies: Current challenges and future perspectives. Tumour Virus Res [Internet]. 2022 Jun 1 [cited 2024 Jul 17];13. Available from: /pmc/articles/PMC9062473/
2. Almomen A, Badran M, Alhowyan AA, Alkholief M, Alshamsan A. Imiquimod-Loaded Chitosan-Decorated Di-Block and Tri-Block Polymeric Nanoparticles Loaded In Situ Gel for the Management of Cervical Cancer. Gels [Internet]. 2023 Sep 1 [cited 2024 Oct 21];9(9):713. Available from: https://www.mdpi.com/2310-2861/9/9/713/htm
3. Tuğcu-Demiröz F, Saar S, Tort S, Acartürk F. Electrospun metronidazole-loaded nanofibers for vaginal drug delivery. Drug Dev Ind Pharm [Internet]. 2020 Jun 2 [cited 2024 Jul 29];46(6):1015–25. Available from: https://pubmed.ncbi.nlm.nih.gov/32393132/

Acknowledgements: The funding was received from Indian Council of Medical Research-Senior Research Fellowship (ICMR-SRF), Government of India and Manipal Academy of Higher Education (MAHE).


Fig 1: Electrospinning of tri-layered Nanofibers First layer, Second layer, and Third layer of Blank nanofiber and CUR-SMC loaded SNFS


Fig 2: Preparation of Hybrid gel (HG) with images of Solution and gel form



Fig 3: X-ray images of live animal - vaginal cavity at different time points after administration of HG without and with mucoadhesive (A and B) polymer in female Wistar rats