A novel phenoxazine derivative suppresses proliferation of human endometrial adenocarcinoma cell lines, inducing G2M accumulation and apoptosis.
We examined the effects of a novel phenoxazine, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx), which was produced by the reaction of 2-amino-5-methyl-phenol with bovine hemoglobin on the proliferation of human endometrial adenocarcinoma cell lines, EN and KLE cells, and on induction of apoptosis and G2M arrest in these cells. Phx inhibited proliferation of these cell lines in a dose- and time-dependent manner, i.e., the inhibition rate of proliferation of EN and KLE cells was 43% and 40%, respectively, in the presence of 50 micro M Phx, and 75% and nearly 100%, in the presence of 100 micro M Phx, after 2 days. When these endometrial adenocarcinoma cells were incubated with a medium containing 100 micro M Phx for 24 h, accumulation of EN and KLE cells in the S and G2M phase and that of apoptotic cells were demonstrated by flow cytometry. Apoptosis of these cells caused by Phx was unlikely to be associated with p53, Bax, and Bcl-2, because the levels of these proteins were not altered regardless of the presence or absence of Phx. The present results suggest that Phx demonstrates antitumor activity against human endometrial adenocarcinoma cell lines EN and KLE cells, by inducing both cell cycle accumulation at S and G2M and apoptosis associated with p53, Bcl-2 and Bax insensitive pathways.
Nakada
Toshihide
T
Department of Obstetrics and Gynecology, Tokyo Medical University, Tokyo 160-0023, Japan.
Isaka
Keiichi
K
Nishi
Hirotaka
H
Osakabe
Yumi
Y
Shimamoto
Takashi
T
Ohyashiki
Kazuma
K
Tomoda
Akio
A
Takayama
Masaomi
M
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D017209:Apoptosis; D002417:Cattle; D002453:Cell Cycle; D002455:Cell Division; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D016889:Endometrial Neoplasms / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D016195:G2 Phase; D006801:Humans; D008938:Mitosis; D010078:Oxazines / Q000737:chemistry / Q000494:pharmacology*; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D013997:Time Factors; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D010078:Oxazines; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; C039203:phenoxazine