Synergistic Anticancer Effect of Paclitaxel and Noscapine on Human Prostate Cancer Cell Lines

Paclitaxel is one of the most common chemotherapeutic drugs used for the treatment of prostate cancer. However, its current clinical utility has been limited due to numerous serious side effects and drug resistance. Noscapine is an antitussive opium alkaloid that showed antitumor activity against a variety of cancer while it has not exhibited severe side effects. This study investigates the anticancer activity of noscapine in combination with paclitaxel against two LNCaP and PC-3 human prostate cancer cell lines. LNCaP and PC-3 cells were treated with noscapine or paclitaxel or combination. Cell viability was determined using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test. Apoptosis was assessed by acridine orange/ ethidium bromide (AO/EB) staining. The mRNA expression of Bax, Bcl-2, AR, and PSA in the cellular response to treatments was investigated. MTT assay indicated the combination treatment of paclitaxel and noscapine significantly decreased viability compared to single-agent treatment and control groups. The results obtained with AO/EB double staining showed increased percentages of apoptotic cells in the presence of the combination of paclitaxel and noscapine. Furthermore, combinational treatment of paclitaxel and noscapine showed significant decrease in the mRNA expression of B-cell CLL/Lymphoma (Bcl-2) and increase in the mRNA expression of Bcl-2-associated X protein (Bax(, and Bax/Bcl-2 ratio in LNCaP and PC-3 cells (P<0.05.( The mRNA expression of androgen receptor (AR) and prostate specific antigen (PSA) decreased in paclitaxel and noscapine combination-treated of LNCaP cells (P<0.05). This study provides a novel concept of combination treatment of paclitaxel and noscapine to improve efficiency in human prostate cancer treatment.