Nutrition and Cancer
ISSN: 0163-5581 (Print) 1532-7914 (Online) Journal homepage: http://www.tandfonline.com/loi/hnuc20
Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells Hyeon-A Kim , Min-Sook Kim , Sang-Hyun Kim & Yoo Kyeong Kim To cite this article: Hyeon-A Kim , Min-Sook Kim , Sang-Hyun Kim & Yoo Kyeong Kim (2014) Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells, Nutrition and Cancer, 66:1, 159-165, DOI: 10.1080/01635581.2014.853814 To link to this article: http://dx.doi.org/10.1080/01635581.2014.853814
Published online: 16 Dec 2013.
Submit your article to this journal
Article views: 185
View related articles
View Crossmark data
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=hnuc20 Download by: [Australian Catholic University]
Date: 09 October 2017, At: 06:59
Nutrition and Cancer, 66(1), 159–165 C 2014, Taylor & Francis Group, LLC Copyright ISSN: 0163-5581 print / 1532-7914 online DOI: 10.1080/01635581.2014.853814
Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells Hyeon-A. Kim and Min-Sook Kim Department of Food & Nutrition, Mokpo National University, Jeonnam, Korea
Sang-Hyun Kim Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Korea
Yoo Kyeong Kim Downloaded by [Australian Catholic University] at 06:59 09 October 2017
Department of Home Economics Education, Kyungpook National University, Daegu, Korea
This study was performed to determine the antimetastatic activities of chili pepper seed on human breast cancer cells. The water extract of chili pepper seeds was prepared and it contained a substantial amount of phenols (131.12 mg%) and no capsaicinoids. Pepper seed extract (PSE) suppressed the proliferation of MDA-MB-231 and MCF-7 cells at the concentration of 10, 25, and 50 μg/ml (MDA-MB-231: IC50 = 20.1 μg/ml, MCF-7: IC50 = 14.7 μg/ml). PSE increased the expression level of E-cadherin up to 1.2-fold of the control in MCF-7 cells. PSE also decreased the secretion of matrix metalloproteinase (MMP)-2 and MMP-9 in MDAMB-231 and MCF-7 cells at the concentration of 25 and 50 μg/ml. PSE treatment significantly suppressed the invasion of MDA-MB231 and MCF-7 cells in a dose-dependent manner. The motility of cancer cells was apparently retarded in the wound healing assay by the PSE treatment. Although our data collectively demonstrate that PSE inhibits invasion and migration of breast cancer cells, further study is needed to identify specific mechanisms and bioactive components contributing to antimetastatic effects of chili pepper seed.
INTRODUCTION Breast cancer is most commonly diagnosed among women worldwide and difficult to be treated when metastasis occurs (1,2). Metastasis is a long journey that cancer cells migrate from the original tumor site to other locations of the body through the blood or the lymphatic routes (3,4). To escape the primary tumor site, cancer cells must attach to and degrade the surrounding extracellular matrix (ECM) and then invade the stromal tissues (5,6). For distant moving, they need to intravasate and transit
Submitted 27 August 2012; accepted in final form 1 October 2013. Address correspondence to Yoo Kyeong Kim, Department of Home Economics Education, Kyungpook National University, #1370 Sangyeok-dong, Buk-gu, Daegu 702-701, Korea. Phone: 82-53-9505929; Fax: 82-53-950-5924. E-mail: [email protected]
through lymph or vascular channels. Once arrived, they need extravasation, further migration, and eventually settle and proliferate at new home (3,4). As metastasis is a complex multistep process, malignant cells should coordinate each step and get over a lot of hurdles to complete metastasis. Hence, the efforts to inhibit metastasis have been focused on the blocking the elements inherent to adhesion, migration, and invasion of cancer cells (1,7–9). Because certain elements of human diet has been known and proven to have chemopreventive ability, considerable efforts have been made to identify phytochemicals possessing capability to interfere with carcinogenic and/or mutagenic processes (10). Hot chili peppers (Capsicum) are among the most popular spices consumed throughout the world. Anticancer activities of chili pepper have been thoroughly investigated and most of the studies focused on the anticarcinogenic activities of capsaicinoids, bioactive and pungent ingredients, in chili pepper (11–15). The content of capsaicinoids, a group of penolic substances, varies and is high in the placental tissue and the fruit of chili pepper (16). Although the highest concentration of capsaicinoids is found in the white pith of the inner wall which holds the seeds, pepper seed itself does not produce capsaicinoids and rarely contains of them (17). Considering a number of reports on anticarcinogenic activities of chili pepper, it is surprising that few literatures are available regarding on those of pepper seed. Therefore, in the present study, we investigated the anticancer activities of pepper seed extract (PSE) and found that PSE has anti-metastatic activities on human breast cancer cells. MATERIALS AND METHODS Preparation of the Water Extract Pepper seeds (Capsicum annuum L.) were ground and the powder was stored at −20◦ C until used. The pepper seed
159
160
H.-A. KIM ET AL.
powder was mixed with 5-folds of water (1:5, w/w) and extracted using super-high pressure liquefying system (TFS-10L, DIMA Puretech Co. Ltd., Japan) at 100 MPa and 50◦ C for 24 h.
Downloaded by [Australian Catholic University] at 06:59 09 October 2017
Measurement of Phenol Content Total phenol content of PSE was determined using the FolinCiocalteu colorimetric method (18,19) with some modification. Briefly, the extract (2 mL) was mixed with 2 mL of 50% FoilnCiocalteu’s reagent and 2 mL of 10% Na2 CO3 . After incubation for 1 h at room temperature, the absorbance was measured at 700 nm using Spectrophotometer (UV-1601, Shimadzu Co., Kyoto, Japan). The result was expressed as gallic acid equivalents (mg gallic acid/100 g extract). Cells and Culture Conditions The MDA-MB-231 and MCF-7 human breast cancer cell lines were obtained from the American Type Culture and Collection (Rockville, MD). All cells were grown in Dulbecco’s modified Eagle’s medium (DMEM; Gibco, Gaithersburg, MD), supplemented with penicillin 100 units/ml, streptomycin 100 μg/ml and 10% fetal bovine serum, and incubated in a humidified incubator at 37◦ C and 5% CO2 . Cultures used for subsequent experiments were at
ISSN: 0163-5581 (Print) 1532-7914 (Online) Journal homepage: http://www.tandfonline.com/loi/hnuc20
Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells Hyeon-A Kim , Min-Sook Kim , Sang-Hyun Kim & Yoo Kyeong Kim To cite this article: Hyeon-A Kim , Min-Sook Kim , Sang-Hyun Kim & Yoo Kyeong Kim (2014) Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells, Nutrition and Cancer, 66:1, 159-165, DOI: 10.1080/01635581.2014.853814 To link to this article: http://dx.doi.org/10.1080/01635581.2014.853814
Published online: 16 Dec 2013.
Submit your article to this journal
Article views: 185
View related articles
View Crossmark data
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=hnuc20 Download by: [Australian Catholic University]
Date: 09 October 2017, At: 06:59
Nutrition and Cancer, 66(1), 159–165 C 2014, Taylor & Francis Group, LLC Copyright ISSN: 0163-5581 print / 1532-7914 online DOI: 10.1080/01635581.2014.853814
Pepper Seed Extract Suppresses Invasion and Migration of Human Breast Cancer Cells Hyeon-A. Kim and Min-Sook Kim Department of Food & Nutrition, Mokpo National University, Jeonnam, Korea
Sang-Hyun Kim Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Korea
Yoo Kyeong Kim Downloaded by [Australian Catholic University] at 06:59 09 October 2017
Department of Home Economics Education, Kyungpook National University, Daegu, Korea
This study was performed to determine the antimetastatic activities of chili pepper seed on human breast cancer cells. The water extract of chili pepper seeds was prepared and it contained a substantial amount of phenols (131.12 mg%) and no capsaicinoids. Pepper seed extract (PSE) suppressed the proliferation of MDA-MB-231 and MCF-7 cells at the concentration of 10, 25, and 50 μg/ml (MDA-MB-231: IC50 = 20.1 μg/ml, MCF-7: IC50 = 14.7 μg/ml). PSE increased the expression level of E-cadherin up to 1.2-fold of the control in MCF-7 cells. PSE also decreased the secretion of matrix metalloproteinase (MMP)-2 and MMP-9 in MDAMB-231 and MCF-7 cells at the concentration of 25 and 50 μg/ml. PSE treatment significantly suppressed the invasion of MDA-MB231 and MCF-7 cells in a dose-dependent manner. The motility of cancer cells was apparently retarded in the wound healing assay by the PSE treatment. Although our data collectively demonstrate that PSE inhibits invasion and migration of breast cancer cells, further study is needed to identify specific mechanisms and bioactive components contributing to antimetastatic effects of chili pepper seed.
INTRODUCTION Breast cancer is most commonly diagnosed among women worldwide and difficult to be treated when metastasis occurs (1,2). Metastasis is a long journey that cancer cells migrate from the original tumor site to other locations of the body through the blood or the lymphatic routes (3,4). To escape the primary tumor site, cancer cells must attach to and degrade the surrounding extracellular matrix (ECM) and then invade the stromal tissues (5,6). For distant moving, they need to intravasate and transit
Submitted 27 August 2012; accepted in final form 1 October 2013. Address correspondence to Yoo Kyeong Kim, Department of Home Economics Education, Kyungpook National University, #1370 Sangyeok-dong, Buk-gu, Daegu 702-701, Korea. Phone: 82-53-9505929; Fax: 82-53-950-5924. E-mail: [email protected]
through lymph or vascular channels. Once arrived, they need extravasation, further migration, and eventually settle and proliferate at new home (3,4). As metastasis is a complex multistep process, malignant cells should coordinate each step and get over a lot of hurdles to complete metastasis. Hence, the efforts to inhibit metastasis have been focused on the blocking the elements inherent to adhesion, migration, and invasion of cancer cells (1,7–9). Because certain elements of human diet has been known and proven to have chemopreventive ability, considerable efforts have been made to identify phytochemicals possessing capability to interfere with carcinogenic and/or mutagenic processes (10). Hot chili peppers (Capsicum) are among the most popular spices consumed throughout the world. Anticancer activities of chili pepper have been thoroughly investigated and most of the studies focused on the anticarcinogenic activities of capsaicinoids, bioactive and pungent ingredients, in chili pepper (11–15). The content of capsaicinoids, a group of penolic substances, varies and is high in the placental tissue and the fruit of chili pepper (16). Although the highest concentration of capsaicinoids is found in the white pith of the inner wall which holds the seeds, pepper seed itself does not produce capsaicinoids and rarely contains of them (17). Considering a number of reports on anticarcinogenic activities of chili pepper, it is surprising that few literatures are available regarding on those of pepper seed. Therefore, in the present study, we investigated the anticancer activities of pepper seed extract (PSE) and found that PSE has anti-metastatic activities on human breast cancer cells. MATERIALS AND METHODS Preparation of the Water Extract Pepper seeds (Capsicum annuum L.) were ground and the powder was stored at −20◦ C until used. The pepper seed
159
160
H.-A. KIM ET AL.
powder was mixed with 5-folds of water (1:5, w/w) and extracted using super-high pressure liquefying system (TFS-10L, DIMA Puretech Co. Ltd., Japan) at 100 MPa and 50◦ C for 24 h.
Downloaded by [Australian Catholic University] at 06:59 09 October 2017
Measurement of Phenol Content Total phenol content of PSE was determined using the FolinCiocalteu colorimetric method (18,19) with some modification. Briefly, the extract (2 mL) was mixed with 2 mL of 50% FoilnCiocalteu’s reagent and 2 mL of 10% Na2 CO3 . After incubation for 1 h at room temperature, the absorbance was measured at 700 nm using Spectrophotometer (UV-1601, Shimadzu Co., Kyoto, Japan). The result was expressed as gallic acid equivalents (mg gallic acid/100 g extract). Cells and Culture Conditions The MDA-MB-231 and MCF-7 human breast cancer cell lines were obtained from the American Type Culture and Collection (Rockville, MD). All cells were grown in Dulbecco’s modified Eagle’s medium (DMEM; Gibco, Gaithersburg, MD), supplemented with penicillin 100 units/ml, streptomycin 100 μg/ml and 10% fetal bovine serum, and incubated in a humidified incubator at 37◦ C and 5% CO2 . Cultures used for subsequent experiments were at
