Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanisms of action

Introduction The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA). Methods KPL-1 cell growth was assessed by colorimetric 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; cell cycle progression and mode of cell death were examined by flow cytometry; and levels of expression of p53, p21Cip1/Waf1, cyclin D1, Bax, and Bcl-2 proteins were examined by Western blotting analysis. In vivo tumor growth was examined by injecting KPL-1 cells subcutaneously into the area of the right thoracic mammary fat pad of female athymic mice fed a CDHA diet. Results CDHA inhibited KPL-1 cells more effectively than did DHA (50% inhibitory concentration for 72 hours: 97 μmol/l and 270 μmol/l, respectively). With both CDHA and DHA growth inhibition was due to apoptosis, as indicated by the appearance of a sub-G1 fraction. The apoptosis cascade involved downregulation of Bcl-2 protein; Bax expression was unchanged. Cell cycle progression was due to G0/G1 arrest, which involved increased expression of p53 and p21Cip1/Waf1, and decreased expression of cyclin D1. CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins in a manner similar to that of parent DHA. In the athymic mouse system 1.0% dietary CDHA, but not 0.2%, significantly suppressed growth of KPL-1 tumor cells; CDHA tended to decrease regional lymph node metastasis in a dose dependent manner. Conclusion CDHA inhibited growth of KPL-1 human breast cancer cells in vitro more effectively than did DHA. The mechanisms of action involved modulation of apoptosis cascade and cell cycle progression. Dietary CDHA at 1.0% suppressed KPL-1 cell growth in the athymic mouse system.</p

Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanisms of action Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanis

Abstract Introduction The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA)

Esophageal Large-Cell Neuroendocrine Carcinoma with Inconsistent Response to Treatment in the Primary and Metastatic Lesions

Esophageal large-cell neuroendocrine carcinoma (NEC) is a rare malignant tumor that is characterized by high-grade malignancy and a poor prognosis. However, the rarity of esophageal NEC has prevented the development of an established treatment, and no reports have described a discrepancy in the effectiveness of cisplatin plus irinotecan between primary and metastatic lesions. A 43-year-old Japanese man was referred to our hospital with refractory epigastralgia. A previous gastrointestinal endoscopy had revealed a 50-mm type 2 tumor in the abdominal esophagus. The pathological findings indicated poorly differentiated squamous cell carcinoma. Contrast-enhanced computed tomography revealed a metastatic liver tumor. One cycle of fluorouracil and cisplatin was not effective, and endoscopy was repeatedly performed. The pathological findings indicated a large-cell malignant tumor with tumor cells that were positive for CD56, synaptophysin, and Ki-67 (&#x3e; 80%). Based on a diagnosis of esophageal large-cell NEC with a metastatic liver tumor, the patient received cisplatin plus irinotecan biweekly. After 4 months, computed tomography revealed marked shrinkage of the metastatic tumor, but the patient complained of dysphagia. Endoscopy revealed enlargement of the primary tumor, which was then treated using radiotherapy plus fluorouracil and cisplatin. The primary tumor subsequently shrank, and the patient’s symptoms were relieved, but the metastatic tumor grew. Thus, chemoradiotherapy could be an option for managing a primary esophageal large-cell NEC that does not respond to chemotherapy alone. However, the possibility of an inconsistent response to therapy in primary and metastatic lesions should be considered

Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanisms of action

Introduction The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA). Methods KPL-1 cell growth was assessed by colorimetric 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; cell cycle progression and mode of cell death were examined by flow cytometry; and levels of expression of p53, p21Cip1/Waf1, cyclin D1, Bax, and Bcl-2 proteins were examined by Western blotting analysis. In vivo tumor growth was examined by injecting KPL-1 cells subcutaneously into the area of the right thoracic mammary fat pad of female athymic mice fed a CDHA diet. Results CDHA inhibited KPL-1 cells more effectively than did DHA (50% inhibitory concentration for 72 hours: 97 μmol/l and 270 μmol/l, respectively). With both CDHA and DHA growth inhibition was due to apoptosis, as indicated by the appearance of a sub-G1 fraction. The apoptosis cascade involved downregulation of Bcl-2 protein; Bax expression was unchanged. Cell cycle progression was due to G0/G1 arrest, which involved increased expression of p53 and p21Cip1/Waf1, and decreased expression of cyclin D1. CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins in a manner similar to that of parent DHA. In the athymic mouse system 1.0% dietary CDHA, but not 0.2%, significantly suppressed growth of KPL-1 tumor cells; CDHA tended to decrease regional lymph node metastasis in a dose dependent manner. Conclusion CDHA inhibited growth of KPL-1 human breast cancer cells in vitro more effectively than did DHA. The mechanisms of action involved modulation of apoptosis cascade and cell cycle progression. Dietary CDHA at 1.0% suppressed KPL-1 cell growth in the athymic mouse system.</p

Cell cycle analysis of KPL-1 cells grown in medium alone or treated with 270 μmol/l docosahexaenoic acid (DHA) or 97 μmol/l conjugated DHA (CDHA) 50% inhibitory concentration IC for 72 hours, respectively) for 72 hours

<p><b>Copyright information:</b></p><p>Taken from "Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth and : potential mechanisms of action"</p><p>Breast Cancer Research 2004;6(4):R291-R299.</p><p>Published online 26 Apr 2004</p><p>PMCID:PMC468623.</p><p>Copyright © 2004 Tsujita-Kyutoku et al.; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL</p> Appearance of sub-Gfraction is seen after DHA and CDHA treatment