Raphanus sativus L. seed extracts induce apoptosis and reduce migration of oral squamous cell carcinoma KB and KB^CD133+cells by downregulation of β-catenin

Abstract

Although, oral cancer therapies have been developed for decades, patient survival rates have not changed. Side effects of chemotherapy and radiotherapy reduce quality of life of patients and it remains difficult to treat oral cancers due to the presence of cancer stem cells (CSCs) that cause recurrence and metastasis. Therefore, we search for natural products that affect oral cancer cells including oral cancer stem cells. In the present study, we investigated the anticancer effects of Raphanus sativus L. seed (RSLS) extracts on oral squamous cell carcinoma KB cells and CSC-like KB^CD133+ cells. CD133 plays an important role in CSCs and physically binds to β-catenin to activate the β-catenin signaling targets. Therefore, a natural extract that can inhibit β-catenin act in may be effective anticancer drug acquiring CSC. Of the natural product extract candidates, RSLS extracts induced apoptosis in KB and KB^CD133+ cells and inhibited nuclear translocation of β-catenin cell migration and invasion rates. Treatment of RSLS extracts resulted in increases of Axin and it leds to reductions of β-catenin in KB and KB^CD133+ cells. Hence, the result suggests that RSLS are potential candidate for anticancer drug against oral cancer cells and CSCs.

Abbreviations
CSC	=	cancer stem cells
OSCC	=	squamous cell carcinoma cells
RSLS	=	Raphanus sativus L. seed.

Availability of data and materials

All data generated or analyzed during this study are included in this article.

Authors’ contributions

The author contributed to this paper as follows. Experimental design: KHA, HJJ, OJK, BKK Performed the experiments: KHA, HJJ Interpretation: KHA, HEK, HJC, BGK, OJK Drafting the work: KHA, HEK, HJC Find references: SHS, YZH, YK Data analysis. All authors read and approved the final manuscript.

Ethics approval and consent to participate

Not applicable.

Consent for publication

All the authors have read and approved the paper for publication.

Competing interests

The authors declare that they have no competing interests.

Additional information

Funding

This work was supported by two National Research Foundation of Korea grants (NRF-2016R1D1A1B03930314 and NRF-2016R1D1A1B03931467) funded by the Korean government.