Aloe Emodin Induces G2/M Cell Cycle Arrest and Apoptosis via Activation of Caspase-6 in Human Colon Cancer Cells

Abstract

Aloe emodin (AE), a natural anthraquinone, is reported to have antiproliferative activity in various cancer cell lines. In this study, we analyzed the molecular mechanisms involved in the growth-inhibitory activity of this hydroxyanthraquinone in colon cancer cell, WiDr. In our observation AE inhibited cell proliferation by arresting the cell cycle at the G2/M phase and inhibiting cyclin B1. AE appreciably induced cell death specifically through the induction of apoptosis and by activating caspases 9/6. Apoptotic execution was found to be solely dependent on caspase-6 rather than caspase-3 or caspase-7. This is the first study indicating that the AE induces apoptosis specifically through the activation of caspase-6.

Aloe-emodin suppresses esophageal cancer cell TE1 proliferation by inhibiting AKT and ERK phosphorylation

“…Aloe-emodin has anti-proliferative effects and induces cellular apoptosis (27)(28)(29)(30). Aloe-emodin has anti-cancer activity in neuroectodermal tumors (31), nasopharyngeal carcinoma (32), lung squamous cell carcinoma (33), hepatoma cells (34), gastric cancer (35) and prostate cancer (36).…”

Aloe Vera and Cancer

“…It is claimed to be effective in a variety of applications, but it is potential effect on cancer has been of particular [24] Laboratory Breast cancer Suppressed the proliferation Suboj P et al [25] Laboratory Colon cancer Induced apoptosis Lee HZ et al [26] Laboratory Lung carcinoma Inhibited cell growth in cell lines Chen HC et al [27] Laboratory Promyelocytic leukemia Inhibited cell growth in cell lines Pecere T et al [28] Laboratory Neuroectodermal tumors Inhibited cell growth in cell lines Pan Q et al [29] Laboratory Colorektal cancer Inhibited the angiogenesis through VEGF suppression Yonehara A et al [30] Laboratory Neuroblastoma Suppressing the cyclin D2 transcription level Liu K et al [31] Laboratory Prostate cancer Inhibit cancer cell proliferation by acting through mammalian target of rapamycin complex 2 Heggie S et al [13] Clinical Breast cancer No significant benefit in skin problems caused by radiotherapy Williams MS et al [14] Clinical -No significant benefit in skin problems caused by radiotherapy George J et al [16] Clinical Head and neck cancer Delay the start time of radiotherapy induced skin lesions and reduce their intensity Lissoni P et al [20] Clinical Metastatic cancers Tumor regression Su CK et al [36] Clinical Head and neck cancer No contribution in terms of reducing the symptoms and increasing quality of life interest in recent years. The most advocated benefit of Aloe vera for a cancer patient is its alleged ability to prevent and treat skin lesions caused by radiotherapy.…”

“…[23] In a study on breast cancer cell lines, it once again suppressed proliferation, [24] and in another study on colon cancer cell lines, it induced apoptosis through the activation of caspase-6. [25] Similarly, there are also studies showing that Aloe emodin inhibited cell growth in cell lines of lung cancer, leukemia, and neuroectodermal cancer. [26][27][28] In another study, Aloin, another anthraquinone component in aloe, inhibited angiogenesis through suppression of vascular endothelial growth factor (VEGF).…”

Aloe Emodin Induces Apoptosis in ER+-breast Cancer Cells; MCF-7 through IGF-1R Signalling Pathway

“…Despite its significant contribution in clinical setting, almost all patients with meta-static stage ultimately relapsed from their disease and are fatal (Ring & Dowsett 2004), thus emphasizing the importance of searching for a new chemotherapy regimens. Recently, aloe emodin has been recommended as a potential natural source of chemotherapeutic agents due to its cytotoxicity on several cancer cells, such as prostate (Lin et al 2006), colon (Suboj et al 2012) and hepatoma (Lu et al 2007). The capacity of aloe emodin to induce apoptosis in these cells through several mechanisms has been well documented.…”