Lac color inhibits development of rat thyroid carcinomas through targeting activation of plasma hyaluronan-binding protein.
Coccid-derived natural food colorants contain active ingredients that potentiate inhibition of tissue proteolysis mediated by activation of plasma hyaluronan-binding protein (PHBP). In the present study, we examined the effect of lac color (LC) and cochineal extract (CE), representative coccid-derived colorants containing laccaic acid and carminic acid as active ingredients, in an intracapsular invasion model of experimental thyroid cancers using rats. One week after initiation with N-bis(hydroxypropyl)nitrosamine, male F344/NSIc rats were fed a powdered diet containing 5.0% LC or 3.0% CE during promotion with 0.15% sulfadimethoxine (SDM) in the drinking water for 13 weeks. Capsular invasive carcinomas (CICs) and lung metastases were decreased by LC treatment and accompanied by transcript downregulation on angiogenesis and PHBP-related tissue proteolysis in CICs. In contrast, CE upregulated angiogenesis-related genes in CICs. PHBP was expressed in capsular macrophages and thyroid proliferative lesions with increased intensity in CICs, and LC decreased PHBP-expressing CICs. The size of CICs and their proliferation activity, however, were unchanged compared with those treated with SDM alone. Suppression of cancer by invasion by LC was more evident after an eight-week treatment, exhibiting a profound decrease in tenascin-C-positive early invasive foci and marked reductions in capsular inflammation and fibrosis. These results suggest that LC and CE exerted dissimilar effects on CIC development, the former suppressing the initial step of neoplastic cell invasion into the capsule by targeting PHBP activity of macrophages and neoplastic cells on tissue proteolysis involving inflammatory responses and angiogenesis, and the latter promoting angiogenesis of developed CICs at later stages.
Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan.
Sayaka
S
Kemmochi
Shingo
S
Yamamichi
Keisuke
K
Shimamoto
Nobuhiko
N
Onda
Keiji
K
Hasumi
Kazuhiko
K
Suzuki
Kunitoshi
K
Mitsumori
Makoto
M
Shibutani
D000818:Animals; D001391:Azo Compounds / Q000627:therapeutic use*; D018265:Carcinoma, Papillary, Follicular / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology*; D049109:Cell Proliferation; D004195:Disease Models, Animal; D018960:Hyaluronan Receptors / Q000097:blood*; D008297:Male; D009282:Naphthalenesulfonates; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D015398:Signal Transduction / Q000502:physiology; D013412:Sulfadimethoxine / Q000009:adverse effects; D013963:Thyroid Hormones / Q000097:blood; D013964:Thyroid Neoplasms / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology*
D001391:Azo Compounds; D018960:Hyaluronan Receptors; D009282:Naphthalenesulfonates; D013963:Thyroid Hormones; C009765:lac dye; D013412:Sulfadimethoxine; D051057:Proto-Oncogene Proteins c-akt; D051059:PTEN Phosphohydrolase; C576297:ponceau 4R