Expression and distribution of secretory phospholipase A₂ in human skin melanoma cells and tissues

Key words: 
• secretory phospholipase A₂ /
• melanoma /
• expression /
• distribution

Abstract: Objective :To investigate the expression and distribution of secretory phospholipase A₂(sPLA₂) in A375 human malignant melanoma cells and melanoma tissues compared with normal human skin cells and tissues. Methods :The expression of sPLA₂ in the clear supernatant and intra-cellular of cells was detected by ELISA method and Western Blot method,respectively.Immunohistochemical method was used to investigate the expression and distribution of sPLA₂ in the human skin tissues. Results :The levels of sPLA₂ in the clear supernatant of A375 malignant melanoma cells was(177.27±13.57) pg/mL,which was significantly higher(P<0.05) than the group of human epidermal HaCaT cells(21.42±5.05) pg/ml and the group of dermal fibroblast cells(2.75±1.23) pg/mL,respectively.The ratio of sPLA₂/GAPDH in the A375 cells was(7.03±1.31),which was also significantly higher(P<0.05) than the group of human epidermal HaCaT cells(1.45±0.37) and the group of dermal fibroblast cells(0.31±0.11),respectively.Many sPLA₂ positive cells and granules were presented in the tumor tissues.In contrast,positive cells and granules above were unobserved in the normal human epidermal and dermal tissues. Conclusion :sPLA₂ is expressed and distributed at higher levels in A375 human malignant melanoma cells and melanoma tissues compared with the normal skin cells and tissues,indicating the sPLA₂ maybe a novel trigger for targeted drug delivery to skin melanoma.