*The Plant Extract of Pao Pereira Potentiates Carboplatin Effects Against Ovarian Cancer

Jun Yu, PhD, Qi Chen, PhD.  – ISSN 1388-0209 print/ISSN 1744-5116 – Pharmaceutical Biology

Recent research conducted at the University of Kansas Medical Center shows that an herbal preparation of Pao pereira, provided by Natural Source International, Ltd. could be extremely helpful.  It concludes that “In vivo, Pao pereira alone suppressed tumor growth by 79% and decreased volume of ascites by 55%. When Pao pereira was combined with carboplatin, tumor inhibition reached 97% and ascites was completely eradicated. Pao pereira possess potent antitumor activity and could enhance carboplatin effect, and therefore holds therapeutic potential in the treatment of ovarian cancer.”

This is a breakthrough study considering that The American Cancer Society estimates that in 2013, about 22,240 new cases of ovarian cancer will be diagnosed and 14,030 women will die of ovarian cancer in the United States. According to the data, the mortality rates for ovarian cancer have not improved in the forty years since the “War on Cancer” was declared.

The herbal preparation of Pao pereira long been used by oncologic patients and Integrative Medicine practitioners in South America. This study investigates the anticancer effects of Pao pereira (Pao), either alone or in combination with chemotherapy drugs (carboplatin), in preclinical ovarian cancer models.

The results of the study offer a breakthrough for ovarian cancer research!

Pao pereira selectively inhibited ovarian cancer cell growth but induced apoptosis (programmed cell death) and also Pao pereira greatly enhanced chemo drug cytotoxicity.

In vivo, Pao pereira alone suppressed tumor growth by 79% and decreased volume of ascites by 55%. When Pao pereira was combined with Chimio therapy, tumor inhibition reached 97% and ascites was completely eradicated. The researchers conclude that Pao Pereira has therapeutic potential in the treatment of ovarian cancer.

Abstract

Herbal preparation of Pao pereira [Geissospermum vellosii Allem (Apocynaceae)] has long been used by oncologic patients and Integrative Medicine practitioners in South America. However, its anticancer activities have not been systematically studied. Objective: To investigate the anticancer effects of b-carboline alkaloids-enriched extract from Pao pereira (Pao), either alone or in combination with carboplatin, in preclinical ovarian cancer models. Materials and methods: Cytotoxicity of Pao (0–800 mg/ml) against different ovarian cancer cell lines and an immortalized epithelial cell line was detected by flow cytometry, MTT assay and colony formation in soft agar. Combination of Pao and carboplatin, a primary chemotherapeutic drug for ovarian cancer, was evaluated using Chou-Talalay’s methods. Mice bearing intraperitoneally spread ovarian cancer were treated with 20 or 50 mg/kg/day Pao by i.p. injection. Carboplatin at 15 mg/kg/week i.p. was compared and combined to Pao treatments. Results: Pao selectively inhibited ovarian cancer cell growth with IC50 values of 180–235 mg/ml, compared to 537 mg/ml in normal cells. Pao induced apoptosis dose- and time-dependently and completely inhibited colony formation of tumor cells in soft agar at 400 mg/ml. Pao greatly enhanced carboplatin cytotoxicity, with dose reduction (DRIs) for carboplatin at 1.2–10 fold. In vivo, Pao alone suppressed tumor growth by 79% and decreased volume of ascites by 55%. When Pao was combined with carboplatin, tumor inhibition reached 97% and ascites was completely eradicated. Discussion and conclusion: Pao possess potent antitumor activity and could enhance carboplatin effect, and therefore holds therapeutic potential in the treatment of ovarian cancer.