مقالات پذیرفته شده در پنجمین کنگره بین المللی زیست پزشکی
Response surface method optimization of photodynamic therapy conditions for treatment of skin cancer using zinc phthalocyanine-nanoemulsions
Response surface method optimization of photodynamic therapy conditions for treatment of skin cancer using zinc phthalocyanine-nanoemulsions
Fatemeh Saeedi,1,* Malahat Rezaee,2Mahnoosh Fatemi,3Fereshte Ghandehari,4Ramesh Monajemi,5
1. Department of Biochemistry, Falavarjan Branch, Islamic Azad University, Isfahan, Iran 2. Department of Biochemistry, Falavarjan Branch, Islamic Azad University, Isfahan, Iran 4. Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
Introduction: Melanoma is the most dangerous form of skin cancer, with a steeply rising incidence and a poor prognosis in its advanced stages. Melanoma is much less common than the other types but much more likely to invade nearby tissue and spread to other parts of the body. Since melanoma is highly resistant to traditional chemotherapy and radiotherapy, various alternative treatments are being investigated to develop melanoma therapy. Photodynamic therapy (PDT) has been proposed as an effective modality for melanoma therapy, superior to traditional forms of therapy because of its noninvasiveness, fewer side effects, negligible drug resistance, and low systemic toxicity. PDT employs a photosensitizer (PS) and visible light in the presence of oxygen, leading to production of cytotoxic reactive oxygen species, which can damage the cellular organelles and cause cell death. The aim of this study was to optimize phothodynamic therapy conditions of zinc phthalocyanine as a photosensitizer incorporated in a nanoemulsion system to achieve the lowest viability of skin cancer cell line.
Methods: Response surface methodology (RSM) was employed to study the effect of the drug dose (10, 20, 40 and 80 µg/ml) and laser dose (1.25, 2.5, 5 and 20 J/cm3) as independent factors on viability percentage of melanoma cell line, as response. The incubation time was hold constant at 4 hr. The melanoma cancer cell line was B16F0 and the cell viability was determined using MTT assay. A three-factor central composite rotatable design (CCRD) was used to determine the effect of the factors on the response. Experimental runs were generated by using Design-Expert version 10 (State-Ease Inc., Statistics Made Easy, Minneapolis, MN, USA). Experimental data was analyzed by multiple regressions to fit all the experimental data to the partial third order polynomial equation. An analysis of variance (ANOVA) and R2 (coefficient of determination) statistic was carried out to evaluate significant differences between independent variables.
Results: The results showed that the experimental data could be sufficiently fitted into a third-order polynomial model with multiple regression coefficients (R2) and adjusted R2 of 0.88 and 0.76, respectively. The F-value of the model in ANOVA was 7.36 implied that the model was significant. The non-significant lack of fit (P-value = 0.074) indicated that the partial cubic polynomial model was an appropriate model for predicting the data. Among the linear, quadratic, cubic and interaction terms, the quadratic term of drug concentration was the most effective factors (P-value = 0.003). In addition, PRESS was 1700.02, and adequate precision was 6.588, which confirm accuracy of the model. The optimum photodynamic conditions were drug concentration of 78.28 µg/ml and laser dose of 17.22 J/cm3. The achieved viability was 10% for the cancer cell line.
Conclusion: The results showed that RSM was efficient in modeling and optimizing photodynamic parameters, and zinc phthalocyanine-nanoemulsions had significant effects on reduction of viability percentage of skin cancer cell line.