Optimal Scheduling of Combination of Photodynamic Therapy with Anti-Angiogenic Therapy for Effective Control of Local Tumor and Distant Metastasis

Arshi Malik^1*, Mohmed Abd Ellatif ^1,4, Basiouny El-Gamal¹, Mohammed Amanullah¹, Sarah Afaq¹, Syed Saleem Haider¹, Awad Saeed Al-Samghan² & Mohammed Yahia Alasmary³

¹Department of Clinical Biochemistry, College of Medicine, King Khalid University, Abha, Saudi Arabia
²Department of Family and Community Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia
³Department of Internal Medicine, Najran University, Najran, Saudi Arabia
⁴Department of Medical Biochemistry, Faculty of Medicine, Mansoura University, Mansoura, Egypt

Arshi Malik, Department of Clinical Biochemistry, College of Medicine, King Khalid University, Abha, Saudi Arabia.

Keywords: Metastasis; Angiogenesis; Avastin; Photodynamic Therapy

Abstract

Angiogenesis is an important component in tumor development, progression and spread. As a result, there are ongoing efforts to combine existing cytotoxic therapy with anti-angiogenic therapy to enhance the efficacy of cancer treatment. However, the optimal scheduling of antiangiogenic therapy with cytotoxic therapy, although crucial for maximizing treatment efficacy, remains unclear. Here, we investigated an optimal protocol for combining Avastin antiangiongenic therapy with photodynamic therapy (PDT), a cytotoxic therapy for various diseases including cancer. We demonstrate that PDT leads to a temporally-transient regulation of vascular endothelial growth factor (VEGF) following treatment. More importantly, combination Avastin therapy was most effective in inhibiting lung metastasis when delivered around the peak of VEGF response following PDT. Considering that temporally transient VEGF regulation was observed following PDT, radiotherapy and chemotherapy, optimal scheduling of combination anti-angiogenic therapy based on temporal dynamics of the VEGF response has implications in a wide range of cancer treatments.

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).