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Rose Bengal-Amphiphilic Peptide Conjugate for Enhanced Photodynamic Therapy of Malignant Melanoma
Simanpreet Kaur Dhillon1, Simon L Porter1, Nermeen Rizk1
1Biomedical Sciences Research Institute , University of Ulster , Coleraine BT52 1SA , Northern Ireland , U.K.
Abstract:
Malignant melanoma is an aggressive skin cancer with poor survival outcomes for patients diagnosed at an advanced stage. While targeted serine/threonine-protein kinase B-Raf (BRAF) and immune checkpoint inhibitors have improved survival outcomes for a proportion of these patients, response rates remain variable. There is a need, therefore, for more effective treatments to bolster the options available for melanoma patients. In this manuscript, we covalently attached Rose Bengal (RB) to the amphipathic peptide (AMP) C(KLAKLAK)2 and determined the effectiveness of the resulting RB-C(KLAKLAK)2 conjugate as a photodynamic therapy (PDT) sensitizer. RB-C(KLAKLAK)2-mediated PDT treatment of subcutaneous B16-F10-Luc2 tumors in C57 mice resulted in lesions that were 479% smaller at the end of the study than animals treated with RB-mediated PDT. The synergistic effect between RB and C(KLAKLAK)2 has been attributed to the AMP sensitizing cells to reactive oxygen species (ROS), making them more susceptible to ROS-induced oxidative stress.
Insights
A novel Rose Bengal and peptide conjugate (RB-C(KLAKLAK)2) significantly enhances photodynamic therapy (PDT) for melanoma. This new treatment led to a 479% reduction in tumor size compared to PDT alone, offering a promising advancement for skin cancer therapy.
Area of Science:
- Oncology
- Biomedical Engineering
- Photochemistry
Background:
- Malignant melanoma presents a significant challenge, especially in advanced stages, with current treatments like BRAF inhibitors and immune checkpoint inhibitors showing variable efficacy.
- There is a critical need for novel therapeutic strategies to improve outcomes for melanoma patients.
Purpose of the Study:
- To develop and evaluate a new photodynamic therapy (PDT) sensitizer by conjugating Rose Bengal (RB) with an amphipathic peptide (AMP) C(KLAKLAK)2.
- To assess the efficacy of the RB-C(KLAKLAK)2 conjugate in treating subcutaneous melanoma tumors in a preclinical mouse model.
Main Methods:
- Covalent attachment of Rose Bengal (RB) to the amphipathic peptide C(KLAKLAK)2 to create the RB-C(KLAKLAK)2 conjugate.
- Photodynamic therapy (PDT) was administered to B16-F10-Luc2 melanoma tumors in C57 mice using the RB-C(KLAKLAK)2 conjugate.
- Tumor size was measured and compared between treatment groups.
Main Results:
- RB-C(KLAKLAK)2-mediated PDT resulted in significantly smaller tumor lesions (479% reduction) compared to RB-mediated PDT alone.
- The amphipathic peptide C(KLAKLAK)2 appears to enhance cellular sensitivity to reactive oxygen species (ROS) generated during PDT.
- This suggests a synergistic effect between RB and C(KLAKLAK)2, leading to increased oxidative stress and tumor cell death.
Conclusions:
- The RB-C(KLAKLAK)2 conjugate is a highly effective photodynamic therapy sensitizer for melanoma.
- The observed synergistic effect, driven by enhanced ROS sensitivity, highlights the potential of this novel conjugate as an improved therapeutic option for aggressive skin cancers.
- Further research into this combination therapy could lead to better treatment strategies for melanoma patients.
