Apoptotic effect of cordycepin combined with cisplatin and/or paclitaxel on MA-10 mouse Leydig tumor cells

The Role of Autophagy in Anti-Cancer and Health Promoting Effects of Cordycepin

Cordycepin is an adenosine derivative isolated from Cordyceps sinensis, which has been used as an herbal complementary and alternative medicine with various biological activities. The general anti-cancer mechanisms of cordycepin are regulated by the adenosine A3 receptor, epidermal growth factor receptor (EGFR), mitogen-activated protein kinases (MAPKs), and glycogen synthase kinase (GSK)-3β, leading to cell cycle arrest or apoptosis. Notably, cordycepin also induces autophagy to trigger cell death, inhibits tumor metastasis, and modulates the immune system. Since the dysregulation of autophagy is associated with cancers and neuron, immune, and kidney diseases, cordycepin is considered an alternative treatment because of the involvement of cordycepin in autophagic signaling. However, the profound mechanism of autophagy induction by cordycepin has never been reviewed in detail. Therefore, in this article, we reviewed the anti-cancer and health-promoting effects of cordycepin in the neurons, kidneys, and the immune system through diverse mechanisms, including autophagy induction. We also suggest that formulation changes for cordycepin could enhance its bioactivity and bioavailability and lower its toxicity for future applications. A comprehensive understanding of the autophagy mechanism would provide novel mechanistic insight into the anti-cancer and health-promoting effects of cordycepin.

Cordycepin Augments the Chemosensitivity of Human Glioma Cells to Temozolomide by Activating AMPK and Inhibiting the AKT Signaling Pathway

Glioblastoma multiforme (GBM) is the most commonly encountered subtype of deadly brain cancer in human adults. It has a high recurrence rate and shows aggressive proliferation. The novel cytotoxic agent temozolomide (TMZ) is now frequently applied as the first-line chemotherapeutic treatment for GBM; however, a considerable number of patients treated with TMZ turn out to be refractory to this drug. Hence, a more effective therapeutic approach is urgently required to overcome this critical issue. Accumulating evidence has shown that both AMPK and AKT are activated by TMZ, while only AMPK contributes to apoptosis via mammalian target of rapamycin (mTOR) inhibition. Accordingly, AKT increases the tumorigenicity and chemoresistance of various tumor cells. In addition, AKT overexpression increases the resistance of glioma cells to TMZ. Cordycepin, a major bioactive component in Cordyceps militaris, exhibits immunomodulatory, anticancer, antioxidant, and anti-inflammatory activities, among other therapeutic effects. To date, whether GBM sensitivity to TMZ can be enhanced by cordycepin largely remains unknown. In the present study, we evaluated the effect of the combined use of cordycepin and TMZ in the treatment of GBM and explored the molecular mechanisms. Notably, we found that treatment with cordycepin led to inhibition of cellular proliferation, migration, and invasion as well as cellular apoptosis and cell cycle arrest in glioma cell lines in vitro. Likewise, the combined treatment with both cordycepin and TMZ synergistically resulted in inhibition of cellular growth, migration, and tumor metastasis as well as induction of cellular apoptosis and cell cycle arrest. Moreover, we also demonstrated that cordycepin effectively enhanced the activation of AMPK and suppressed the activity of AKT, whose activation was only induced by TMZ. Furthermore, there was an apparent reduction in the expression levels of p-mTOR, p-p70S6K, matrix metalloproteinase (MMP)-2, and MMP-9 in the group treated with both cordycepin and TMZ, in comparison with those in the groups treated with either cordycepin or TMZ alone. In vivo, the combination therapy also obviously reduced the tumor volume as well as prolonged the median survival time of xenograft models. In brief, our results suggested that cordycepin augments TMZ sensitivity in human glioma cells at least partially through activation of AMPK and suppression of the AKT signaling pathway. Overall, the combination therapy of cordycepin and TMZ potentially provides a novel option for a better prognosis of patients with GBM in clinical practice.

Cordycepin inhibits chondrocyte hypertrophy of mesenchymal stem cells through PI3K/Bapx1 and Notch signaling pathway

Mesenchymal stem cells (MSCs) are widely used in cartilage tissue engineering to repair articular cartilage defects. However, hypertrophy of chondrocytes derived from MSCs might hinder the stabilization of hyaline cartilage. Thus, it is very important to find a suitable way to maintain the chondrogenic phenotype of chondrocytes. It has been reported that cordycepin has anti-inflammatory and anti-tumor functions. However, the role of cordycepin in chondrocyte hypertrophy remains unclear. Therefore, the objective of this study was to determine the effect of cordycepin on chondrogenesis and chondrocyte hypertrophy in MSCs and ATDC5 cells. Cordycepin upregulated chondrogenic markers including Sox9 and collagen type II while down-regulated hypertrophic markers including Runx2 and collagen type X. Further exploration showed that cordycepin promoted chondrogenesis through inhibiting Nrf2 while activating BMP signaling. Besides, cordycepin suppressed chondrocyte hypertrophy through PI3K/Bapx1 pathway and Notch signaling. Our results indicated cordycepin had the potential to maintain chondrocyte phenotype and reconstruct engineered cartilage. [BMB Reports 2016; 49(10): 548-553]

Effect of Combined Treatment Using Wilfortrine and Paclitaxel in Liver Cancer and Related Mechanism

Background

Liver cancer is a common malignant tumor with high mortality. Currently, effective medicines against liver cancer are still lacking. Paclitaxel is a wide-spectrum anti-tumor agent, while wilfortrine has been shown to have an inhibitory effect on the proliferation of liver cancer cells. This study thus investigated the potential effect of paclitaxel combined with wilfortrine on cultured liver cancer cells and related mechanisms, in order to provide evidence for pathogenesis and treatment of liver cancer.

Material/Methods

Liver cancer cell line HpeG2 was divided into control, paclitaxel, wilfortrine, and combined treatment groups. Cell proliferation was tested by MTT, while invasion was detected in Transwell chamber assay. Apoptotic protein Bcl-2 and Bax expression levels were further quantified using real-time PCR and Western blotting.

Results

Both of those 2 drugs can effectively inhibit cancer cell proliferation, depress invasion ability, increase Bcl-2 expression, and elevate Bax expression levels (p<0.05 in all cases). The combined therapy had better treatment efficacy compared to either of those drugs alone (p<0.05).

Conclusions

The combined treatment using wilfortrine and paclitaxel can inhibit proliferation and invasion of liver cancer cells via down-regulating Bcl-2 and up-regulating Bax, with better efficacy than single use of either drug.