Effect of Turkish propolis extracts on proteome of prostate cancer cell line

Abstract

Background: Propolis is a natural, resinous hive product that has several pharmacological activities. Its composition varies depending on the vegetation, climate, season and environmental conditions of the area from where it was collected. Surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF MS) is a proteomic approach which has been used in cancer proteomics studies. Prostate cancer is one of the most commonly diagnosed cancers in men. It has shown that nutritional supplements rich in polyphenolic compounds such as propolis play a significant role in prostate cancer chemoprevention. The aim of this study is to evaluate if protein expression profile in PC-3 prostate cancer cell lines could be differentiated when incubated with dimethyl sulfoxide and water extracts of Turkish propolis.

Results: The antioxidant potentials of dimethyl sulfoxide and water extracts of propolis were found in correlation with the amount of total phenolic compounds of them. Dimethyl sulfoxide and water extracts of propolis of 20 μg/mL reduced the cell viability to 24.5% and 17.7%, respectively. Statistically significant discriminatory peaks between control PC-3 cells and dimethyl sulfoxide extract of propolis-treated PC-3 cells were found to be the proteomic features at m/z 5143, 8703, 12661, 20184 and 32794, detected by CM10 ProteinChip, and the peak at m/z 3772, detected by Q10 ProteinChip. Between control PC-3 cells and water extract of propolis-treated PC-3 cells, statistically significant discriminatory peaks were found to be the proteomic features at m/z 15846, 16052 and 24658, detected by CM10 ProteinChip and the peaks at m/z 10348, 10899 and 11603, detected by Q10 ProteinChip.

Conclusions: It was concluded that dimethyl sulfoxide and water extracts of Turkish propolis may have anti-proliferative activity through differentiating protein expression profile in PC-3 prostate cancer cell lines along with their antioxidant capacity.

Figure 1

SELDI-TOF mass spectra of DEP-treated and untreated PC-3 cells by CM10 ProteinChip. Protein peaks of the peak 8703 m/z, and that positively correlated with DEP-treated PC-3 cells.

Figure 2

Box plot displays of intensity levels of 8703 m/z betweenDEP-treated and untreated PC-3 cells by CM10 ProteinChip. The comparison of DEP-treated PC-3 cell lysates and control PC-3 cell lysates are performed by using non-parametric Mann Whitney method with Ciphergen Express software, version 3.0.

Figure 3

SELDI-TOF mass spectra of WEP-treated and untreated PC-3 cells by CM10 ProteinChip. Protein peaks of the peaks 15846 m/z, and 16052 m/z that are positively correlated with WEP treatment of PC-3 cells.

Figure 4

Box plot displays of intensity levels of 15846 m/z, and 16052 m/z between WEP-treated and untreated PC-3 cells by CM10 ProteinChip. The comparison of WEP-treated PC-3 cell lysates and control PC-3 cell lysates are performed by using non-parametric Mann Whitney method with Ciphergen Express software, version 3.0.

Figure 5

SELDI-TOF mass spectra of WEP-treated and untreated PC-3 cells by Q10 ProteinChip. Protein peaks of the peak 11603 m/z, and that positively correlated with WEP-treated PC-3 cells.

Figure 6

Box plot displays of intensity levels of 11603 m/z between WEP-treated and untreated PC-3 cells by Q10 ProteinChip. The comparison of WEP-treated PC-3 cell lysates and control PC-3 cell lysates are performed by using non-parametric Mann Whitney method with Ciphergen Express software, version 3.0.