Alpha-TEA plus cisplatin reduces human cisplatin-resistant ovarian cancer cell tumor burden and metastasis.
A novel nonhydrolyzable ether-linked acetic acid analog of vitamin E, 2,5,7,8-tetramethyl-2R-(4R,8R,12-trimethyltridecyl)-chroman-6-yloxyacetic acid (alpha-TEA) in combination with cisplatin, reduces tumor burden of A2780/cp70 (cp70) cisplatin-resistant human ovarian cancer cells xenografted into immune compromised nude mice. Two xenograft studies were conducted using cp70 cells stably expressing green fluorescent protein (cp70-GFP) subcutaneously transplanted into NU/NU mice. For studies 1 and 2, alpha-TEA was formulated in liposomes and delivered by aerosol such that approximately 36 microg and 72 microg of alpha-TEA were deposited in the respiratory tract of each mouse each day, respectively. Cisplatin at 5 mg/kg was administered by intraperitoneal injections once weekly for the first 3 weeks in Study 1 and on the third and 10th days following treatment initiation in Study 2. The combination alpha-TEA + cisplatin treatment reduced tumor burden and metastasis of cp70-GFP cells in comparison to control mice or mice treated with alpha-TEA or cisplatin singly. A significant reduction (P < 0.001) in growth of subcutaneous transplanted tumors was obtained with alpha-TEA + cisplatin for both studies. Visible metastases were observed in the lungs of animals from control and cisplatin-treated groups but not in animals from the alpha-TEA- or alpha-TEA + cisplatin-treated groups. The alpha-TEA + cisplatin significantly reduced the total number of lung and axillary lymph node micrometastasis (P < 0.03 and P < 0.0001, respectively). Analyses of tumor sections showed the alpha-TEA + cisplatin treatment group, in comparison to control, to have a significantly lower level of cell proliferation (Ki-67 staining; P < 0.0001) and a significantly higher level of apoptosis (terminal deoxynucleotidyl transferase-mediated nick end labeling [TUNEL]; P < 0.0001). In summary, combinations of alpha-TEA + cisplatin significantly reduced tumor burden and metastases in a xenograft model of cisplatin-resistant human ovarian cancer cells. These data show promise for combination alpha-TEA + cisplatin chemotherapy for ovarian cancer.
Anderson
Kristen
K
Division of Nutrition, University of Texas at Austin, Austin, TX 78712-1097, USA.
Lawson
Karla A
KA
Simmons-Menchaca
Marla
M
Sun
Luzhe
L
Sanders
Bob G
BG
Kline
Kimberly
K
D000280:Administration, Inhalation; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000008:administration & dosage; D004195:Disease Models, Animal; D004351:Drug Resistance / Q000502:physiology*; D005260:Female; D006801:Humans; D020287:In Situ Nick-End Labeling; D008081:Liposomes; D051379:Mice; D008819:Mice, Nude; D009362:Neoplasm Metastasis / Q000188:drug therapy*; D009368:Neoplasm Transplantation; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000473:pathology; D024505:Tocopherols; D047368:Tumor Burden / Q000187:drug effects*; D014810:Vitamin E / Q000008:administration & dosage / Q000031:analogs & derivatives*
D008081:Liposomes; D014810:Vitamin E; C488288:2,5,7,8-tetramethyl-2R-(4R,8R,12-trimethyltridecyl)chroman-6-yloxy acetic acid; D002945:Cisplatin; D024505:Tocopherols