Letter to the Editor
Sappanchalcone, a flavonoid isolated from Caesalpinia sappan L., induces caspase-dependent and AIF-dependent apoptosis in human colon cancer cells

https://doi.org/10.1016/j.cbi.2020.109185Get rights and content

Highlights

  • Sappanchalcone reduces the cell proliferation in HCT116 and SW480 cells.

  • Sappanchalcone more strongly induced apoptosis in HCT116 than in SW480 cells.

  • Sappanchalcone induced p53 phosphorylation and caspase activation in HCT116 cells.

  • Sappanchalcone increased ROS and AIF release in HCT116 and SW480 cells.

Abstract

The present study examined the apoptotic effects and the underlying mechanism of sappanchalcone, a major bioactive compound isolated from Caesalpinia sappan L. on human colon cancer cells. To achieve this, we used two different colon cancer cell lines, namely HCT116 (as wild-type p53 cells) and SW480 (as p53-mutant cells) cells. Our results illustrated that sappanchalcone treatment decreased the proliferation and further promoted apoptosis in HCT116 cells compared with the findings in SW480 cells. Sappanchalcone triggered phosphorylation of p53, which is involved in the activation of caspases and increased expression of Bax in HCT116 cells. Conversely, sappanchalcone-treated SW480 cells displayed no change in p53 phosphorylation or caspase activation. In addition, sappanchalcone further increased reactive oxygen species (ROS) levels and apoptosis-inducing factor (AIF) release in both HCT116 and SW480 cells. These data suggest that sappanchalcone induces apoptosis through caspase-dependent and caspases-independent mechanisms that were characterized by decreased Bcl-2 expression, mitochondrial targeting, and altered ROS production and AIF translocation to the nuclei.

Introduction

Undoubtedly, cancer is one of the foremost public health problems worldwide. In particular, colorectal cancer (CRC) is the third most commonly diagnosed form of cancer globally [1]. Its incidence is steadily rising in developing nations. Approximately 1,096,000 new cases of colon cancer were estimated to have occurred in 2018, whereas approximately 704,000 new cases of rectal cancer were expected, together comprising 1.8 million new cases of CRC [2]. CRC is also the second leading cause of cancer death worldwide, being responsible for an estimated 881,000 deaths in 2018 [1]. CRC typically develops from the glandular epithelial cells of the colon. The cancer ascends when certain cells of the epithelium acquire a series of genetic or epigenetic mutations that confer a selective advantage [3]. With aberrantly heightened replication and survival, these hyperproliferative cells give rise to benign adenoma, which may then evolve into carcinoma and metastasize over decades [4]. The treatments for CRC include surgery, cryosurgery, chemotherapy, radiation therapy, and targeted therapy. Although, chemotherapy is the main therapeutic strategy to inhibit cancer cell division, it involves the delivery of drugs to non-target sites, and patients ultimately experience unwanted side effects such as neutropenia, anemia, hand-foot syndrome, diarrhea, gastrointestinal toxicity, mucositis, nausea, vomiting, fatigue, hematologic disorders, and liver toxicity [5]. Therefore, novel agents with fewer or no side effects are needed for the treatment of CRC.

Sappanchalcone, 3-(3,4-dihydroxyphenyl)-1-(4-hydroxy-2-methoxyphenyl)prop-2-en-1-one, is a chalcone that consists of trans-chalcone substituted by hydroxy groups at positions 3, 4, and 4′ and a methoxy group at position 2′. It is isolated from the heartwood of Caesalpinia sappan L. (Leguminosae) [6]. In fact, the heartwood of C. sappan has long been used folk medicine in Asian countries to treat tuberculosis, diarrhea, dysentery, skin infections, and anemia [7,8]. Moreover, sappanchalcone exhibits various pharmacological effects such as neuroprotective, anti-inflammatory, and anti-influenza virus effects and inhibitory effects on antigen-induced β-hexosaminidase release [[9], [10], [11], [12], [13]]. To date, only one report has demonstrated sappanchalcone-induced growth inhibition and apoptosis using human oral cancer cells [14]. However, the effects of sappanchalcone on colon cancer cells have not been reported. Therefore, this study examined the chemotherapeutic effects of sappanchalcone on human colon cancer cells in vitro.

Section snippets

Chemicals and reagents

Sappanchalcone and antibodies against apoptosis-inducing factor (AIF), Bcl-2, and Bax were purchased from Santa Cruz Biotechnology (Santa Cruz, CA, USA). RPMI-1640 medium, fetal bovine serum (FBS), penicillin, and streptomycin were purchased from HyClone (South Logan, UT, USA). Antibodies against cleaved poly (ADP-ribose) polymerase (PARP), cytochrome c oxidase IV, lamin B1, phospho-p53, p53, and cleaved caspase-3, caspase-7, caspase-8, and caspase-9 were purchased from Cell Signaling

Sappanchalcone reduced the proliferation of human colon cancer cells

To assess the inhibitory effect of sappanchalcone on cell growth, HCT116 (p53 wild-type) cells and SW480 (mutant p53) cells were exposed to different concentrations of sappanchalcone for 24, 48, or 72 h. The CCK-8 assay results demonstrated that sappanchalcone markedly inhibited the proliferation of both colon cancer cell lines in a time- and concentration-dependent manner within the concentration range of 10–50 μM (Fig. 1B and C). Following 48 h treatment, IC50 of sappanchalcone in HCT116 and

Discussion

To date, research on sappanchalcone has been extremely limited. Among the published studies, only one reported the cytotoxic effect of sappanchalcone using human oral cancer cells [14]. Therefore, we believed that various studies on the biological and pharmacological activities of sappanchalcone should be conducted. In this aim, we investigated the cytotoxic effects of sappanchalcone on colon cancer cells. To our knowledge, this study is the first to demonstrate the cytotoxic potential of

Conclusions

Our results illustrated that sappanchalcone, a flavonoid isolated from C. sappan, was cytotoxic in p53-intact HCT116 and p53-mutated SW480 colon cancer cells through caspase-dependent and AIF nuclear translocation-mediated caspase-independent pathways. Sappanchalcone could be a promising phytochemical for developing a new anti-cancer drug against colon cancer. Nevertheless, further studies are warranted to evaluate its potential anti-proliferative and anti-cancerous activities in vivo.

CRediT authorship contribution statement

Hee Won Seo: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Writing - original draft. Huiwon No: Investigation, Methodology. Hye Jin Cheon: Data curation, Formal analysis, Investigation, Methodology. Jin-Kyung Kim: Conceptualization, Funding acquisition, Methodology, Project administration, Supervision, Writing - original draft.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This work was supported by a National Research Foundation of Korea grant funded by the government of Korea (NRF- 2019R1H1A2039721).

References (30)

  • P. Rawla et al.

    Epidemiology of colorectal cancer: incidence, mortality, survival, and risk factors

    Przeglad Gastroenterol.

    (2019)
  • I. Ewing et al.

    The molecular genetics of colorectal cancer

    Frontline Gastroenterol.

    (2014)
  • T. Sugai et al.

    Analysis of genetic alterations, classified according to their DNA ploidy pattern, in the progression of colorectal adenomas and early colorectal carcinomas

    J. Pathol.

    (2003)
  • S. Ades, Adjuvant chemotherapy for colon cancer in the elderly: moving from evidence to practice, Oncology 23 (2)...
  • M. Nagai et al.

    Sappanchalcone from Caesalpinia sappan L., the proposed biosynthetic precursor of brazilin

    Yakugaku Zasshi

    (1984)
  • Cited by (11)

    View all citing articles on Scopus
    1

    These authors contributed equally.

    View full text