Anticancer Effects of High Glucosinolate Synthesis Lines of Brassica rapa on Colorectal Cancer Cells

Abstract

Chemoprevention is a method of health control in modern industrialized societies. Traditional breeding (hybridization) has been widely used to produce new (sub)species with beneficial phenotypes. Previously, we produced a number of doubled haploid (DH) lines of Brassica rapa with a high glucosinolate (GSL) content. In this study, we evaluated the anticancer activities of extracts from three selected high-GSL (HGSL)-containing DH lines (DHLs) of Brassica rapa in human colorectal cancer (CRC) cells. The three HGSL DHL extracts showed anti-proliferative activities in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay and pro-apoptotic activities in the cell cycle or annexin V analysis with the induction of pro-apoptotic protein expression in CRC cells. Mechanistically, HGSL DHL extracts inhibited the NF-κB and ERK pathways, leading to a reduction in the nuclear localization of NF-κB p65. In addition, reactive oxygen species were induced by HGSL DHL extract treatment in CRC cells. In conclusion, our data suggest that the newly developed HGSL DHLs possess enhanced anticancer activities and are potentially helpful as a daily vegetable supplement with chemopreventive activities.

Antioxidant and Anti-Inflammatory Activities of High-Glucosinolate-Synthesis Lines of Brassica rapa

“…The production of HGSL DHLs and their deposition in the NCBI database and the Korea Agricultural Culture Collection were previously outlined [ 20 , 21 ]. The plant materials employed in this study were sourced from the same samples harvested and prepared during March and April 2020, consistent with our earlier investigations [ 20 , 21 ].…”

“…The production of HGSL DHLs and their deposition in the NCBI database and the Korea Agricultural Culture Collection were previously outlined [ 20 , 21 ]. The plant materials employed in this study were sourced from the same samples harvested and prepared during March and April 2020, consistent with our earlier investigations [ 20 , 21 ]. Briefly, both pak choi and three HGSL DHLs (DH005, DH014, and DH026) were cultivated for 6 weeks in a greenhouse located at the National Institute of Agricultural Sciences (Jeonju, Republic of Korea).…”

“…The growth conditions included a 16 h photoperiod at 24 °C [ 20 ]. Fresh leaves from the 6-week-old plants were rapidly lyophilized using an FDU-2110 freeze dryer (EYELA, Tokyo, Japan) [ 20 , 21 ]. Each freeze-dried sample (2 g) underwent extraction with 50 mL of deionized distilled water through 1 h of sonication, followed by filtering using Minisart ® 0.45 µm syringe filters (Sartorius, Göttingen, Germany) [ 20 , 21 ].…”

“…Fresh leaves from the 6-week-old plants were rapidly lyophilized using an FDU-2110 freeze dryer (EYELA, Tokyo, Japan) [ 20 , 21 ]. Each freeze-dried sample (2 g) underwent extraction with 50 mL of deionized distilled water through 1 h of sonication, followed by filtering using Minisart ® 0.45 µm syringe filters (Sartorius, Göttingen, Germany) [ 20 , 21 ]. The effectiveness of this sample preparation was validated using GSL content determination through a high-performance liquid chromatography system with a 150 × 3.0 mm inner diameter and 3 µm particle size of an Inertsil ODS-3 column (GL Science, Tokyo, Japan) as described in prior publications [ 20 , 21 ].…”

“…The DHLs selected for their high GSL contents, between 44.12 and 57.04 µmol/g·dry weight (dw), were designated as high GSL (HGLS)-containing DHLs (HGSL DHLs), with the expectation that they would exhibit improved antioxidant and anti-inflammatory properties compared to the parental Brassica rapa [ 20 ]. Moreover, in a separate study, three edible HGSL DHLs (DH005, DH014, and DH026) demonstrated enhanced anticancer effects in human colorectal cancer cells compared to pak choi [ 21 ]. Given the well-established association between colorectal cancer and inflammation, as well as the known beneficial properties of GSLs, it is reasonable to hypothesize that these HGLS DHLs may also possess enhanced anti-inflammatory benefits.…”