Wasp venom peptide improves the proapoptotic activity of alendronate sodium in A549 lung cancer cells

Abstract

Background: Lung cancer in men and women is considered the leading cause for cancer-related mortality worldwide. Anti-cancer peptides represent a potential untapped reservoir of effective cancer therapy.

Methodology: Box-Behnken response surface design was applied for formulating Alendronate sodium (ALS)-mastoparan peptide (MP) nanoconjugates using Design-Expert software. The optimization process aimed at minimizing the size of the prepared ALS-MP nanoconjugates. ALS-MP nanoconjugates' particle size, encapsulation efficiency and the release profile were determined. Cytotoxicity, cell cycle, annexin V staining and caspase 3 analyses on A549 cells were carried out for the optimized formula.

Results: The results revealed that the optimized formula was of 134.91±5.1 nm particle size. The novel ALS-MP demonstrated the lowest IC50 (1.3 ± 0.34 μM) in comparison to ALS-Raw (37.6 ± 1.79 μM). Thus, the results indicated that when optimized ALS-MP nanoconjugate was used, the IC50 of ALS was also reduced by half. Cell cycle analysis demonstrated a significantly higher percentage of cells in the G2-M phase following the treatment with optimized ALS-MP nanoconjugates.

Conclusion: The optimized ALS-MP formula had significantly improved the parameters related to the cytotoxic activity towards A549 cells, compared to control, MP and ALS-Raw.

Fig 1. Diagnostic plots for particle size of ALS-MP nanoconjugates: (A) Box-Cox for power transforms, (B) externally studentized residuals vs. predicted particle size, (C) ex-ternally studentized residuals vs. run number, and (D) predicted vs. actual particle size.

Abbreviations: ALS, Alendronate sodium; MP, Mastoparan peptide.

Fig 2. Response 3D-plots (A-C) and contour 2D-plots (D-F) for the influence of ALS:MP molar ratio (X1), incubation time (X2), and sonication (X3) on the particle size of ALS-MP nanoconjugates.

Fig 3. The in vitro release pattern of drug from optimized ALS-MP and ALS-raw.

Fig 4. Comparative cytotoxicity of various samples in terms of IC50.

*Significantly different from Staurosporine p<0.05, #significantly different from MP p<0.05, $signifi-cantly different from ALS p<0.05.

Fig 5. Effect of various formulations on cell cycle.

*Significantly different from control p<0.05, #significantly different from MP p<0.05, $significantly different from ALS-Raw p<0.05.

Fig 6. Determination of cellular mortality after Annexin V staining by flow cytometry.

*Significantly different from control p<0.05, #significantly different from MP p<0.05, $sig-nificantly different from ALS-Raw p<0.05.

Fig 7. Comparative effects of ALS-MP on Caspase 3.

*Significantly different from control p<0.05, #significantly different from MP p<0.05.