title: [Acquired tumor "robustness" in the case of prostate cancer].
abstract: Tumors are highly robust and maintain their proliferative potential against both a wide range of host-defense mechanisms and anticancer therapies. In this study, we investigated the levels of human leukocyte antigen (HLA) class I, multi-drug resistance 1 (MDR1), and androgen receptor (AR) expressions in untreated prostate cancers harvested by radical prostectomy. The mean percentages of cancer cells expressing HLA class I, MDR1, and AR among the 10 cancer samples were 41, 35, and 74%, respectively. In addition, double-staining of HLA class I and MDR1 revealed the four definite populations (HLA class I(+)/MDR(+), HLA class I(+)/MDR(-), HLA class I (-)/MDR(+), and HLA class I(-)/MDR(-)) in cancer tissues from the majority of cancer patients tested, and the mean percentages of cells expressing these combinations were 13, 29, 22, and 38%, respectively. Similar results were obtained by double staining of HLA class I and AR, except for 2 cases in which HLA class I(-)/AR (+) cancer cells predominated. These results indicated that untreated prostate cancer cells acquired a wide range of genomic mutation, which may have been caused by internal host pressure to eliminate malignant cells, and would provide evidence of the robustness of untreated prostate cancer.
authors.affiliation: Dept. of Immunology, Kurume University School of Medicine.
authors.forename: Shigenori
authors.initials: S
authors.lastname: Homma
authors.forename: Masanori
authors.initials: M
authors.lastname: Noguchi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Sato
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Maeda
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shomura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Komohara
authors.forename: Takashi
authors.initials: T
authors.lastname: Mine
authors.forename: Mamoru
authors.initials: M
authors.lastname: Harada
authors.forename: Akira
authors.initials: A
authors.lastname: Yamada
authors.forename: Satoru
authors.initials: S
authors.lastname: Todo
authors.forename: Kyogo
authors.initials: K
authors.lastname: Itoh
mesh_terms: D000368:Aged; D018432:Drug Resistance, Multiple / Q000276:immunology; D006680:HLA Antigens / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000276:immunology / Q000473:pathology / Q000503:physiopathology*; D011944:Receptors, Androgen / Q000032:analysis
chemical_list: D006680:HLA Antigens; D011944:Receptors, Androgen