Growth inhibitory efficacy of the nutritional herb Psoralea corylifolia in a model of triple‑negative breast cancer

Abstract

Triple-negative breast cancer (TNBC) lacks the expression of estrogen receptor-α (ER-α), progesterone receptor (PR) and amplified human epidermal growth factor receptor-2 (HER-2). Current treatments involve chemotherapy and molecular targeted therapy. These options lead to dose-limiting systemic toxicity and acquired tumor resistance. Moreover, no drug is yet available for the secondary prevention of TNBC. Such limitations underscore a need to investigate non-toxic testable alternatives for the secondary prevention/treatment of TNBC.

Growth Inhibitory Efficacy of Chinese Herbs in a Cellular Model for Triple-Negative Breast Cancer

“…To examine specific growth characteristics of the TNBC model, comparative experiments were performed to monitor the status of proliferative end points in the tumorigenic triple-negative MDA-MB-231 cells and the non-tumorigenic triple negative 184-B5 cells and the data as summarized from [14][15][16][17][18][19][20][21][22][23] demonstrate that relative to the non-tumorigenic cells, the tumorigenic cells exhibit a decrease in the population doubling time, and in the ratio between quiescent and proliferative cells, while saturation density exhibits an increase in favor of the tumorigenic cells. Anchorage independent (AI) growth represents a specific and sensitive in vitro marker for in vivo tumor growth.…”

“…Anchorage independent (AI) growth represents a specific and sensitive in vitro marker for in vivo tumor growth. The data on AI colony number as summarized from [14][15][16][17][18][19][20][21][22][23], also exhibit a substantial increase in the tumorigenic cells (Table 1). These data provide evidence that the hyper-proliferative tumorigenic cells maintain a persistent risk of developing cancer.…”

“…The origin of the source for the test agent and major constituent bio-active agents that have published growth inhibitory evidence are presented in Table 2. It is conceivable that the content of bioactive agents in the herbs is likely to be highly variable because of differing climatic and soil conditions, and anti-proliferative effects of individual agents on cancer cells may involve distinct mechanisms of action [11][12][13][14][15][16].…”

“…Therefore to simulate clinical condition, non-fractionated aqueous extracts of the herbs, as presented in Table 2, are used for the present experiments. The aqueous extracts are prepared following an optimized water extraction method that is used routinely in the published studies [11][12][13][14][15][16]. This procedure is consistent with the method of preparation for patient consumption.…”

“…A number of herbs commonly used in traditional Chinese medicine have exhibited anti-proliferative and pro-apoptotic effects in a cellular model for the Luminal A breast cancer subtype [11][12][13] and also in a model for the triple-negative breast cancer subtype [14][15][16]. At the mechanistic levels, the anti-proliferative effects of the herbs are associated with inhibition of cell cycle progression, and modulated expression of cell cycle regulatory proteins functioning at G 1 and/or G 2 phases of the cell cycle.…”