title: A novel detection strategy for living circulating tumor cells using 5-aminolevulinic acid.
abstract: Most circulating tumor cell (CTC) detection methods have technical limitations, allowing the detection of only cells expressing epithelial antigens, and they cannot identify if the CTCs are alive or dead. Herein, we constructed a novel CTC detection system comprised of filter separation and 5-aminolevulinic acid (5-ALA)-based labeling, termed "Fs-ALA". Blood specimens (7.5 mL) were subjected to this method. Cells enriched on the filter were incubated with 5-ALA and Hoechst 33342 as positive markers for CTCs. Images of the whole filter surface were obtained using a fluorescence microscope. No 5-ALA positive cells were detected in healthy blood specimens. The Fs-ALA method was capable of detecting not only EpCAM-positive, but also EpCAM-negative tumor cells. In the Fs-ALA method, one or more CTCs were detected in samples from 13 of 18 (72.2%) colorectal cancer patients. The Fs-ALA method had a significantly higher CTC detection rate than CellSearch™ in colorectal cancer patients (P <0.05), and only the former was capable of identifying live cells. This method is highly efficient for detecting CTC populations having undergone phenotypic changes, such as epithelial-mesenchymal transition.
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550, Japan; Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsusaka
authors.affiliation: Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan; Reserch & Development Division, Arkray, Inc., Yousuien-nai, 59 Gansuin-cho, Kamigyo-ku, Kyoto 602-0008, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kozuka
authors.affiliation: Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan; Reserch & Development Division, Arkray, Inc., Yousuien-nai, 59 Gansuin-cho, Kamigyo-ku, Kyoto 602-0008, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Takagi
authors.affiliation: Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan; Reserch & Development Division, Arkray, Inc., Yousuien-nai, 59 Gansuin-cho, Kamigyo-ku, Kyoto 602-0008, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.affiliation: Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan.
authors.forename: Sayuri
authors.initials: S
authors.lastname: Minowa
authors.affiliation: Reserch & Development Division, Arkray, Inc., Yousuien-nai, 59 Gansuin-cho, Kamigyo-ku, Kyoto 602-0008, Japan.
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Hirai
authors.affiliation: Cancer Chemotherapy Center, Clinical Chemotherapy, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan. Electronic address: khatake@jfcr.or.jp.
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Hatake
mesh_terms: D000622:Aminolevulinic Acid; D045744:Cell Line, Tumor; D002469:Cell Separation / Q000379:methods*; D002470:Cell Survival; D005374:Filtration; D005770:Gastrointestinal Neoplasms / Q000097:blood / Q000473:pathology*; D006801:Humans; D008856:Microscopy, Fluorescence; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D017319:Photosensitizing Agents; D011237:Predictive Value of Tests
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid
keywords: 5-aminolevulinic acid; Circulating tumor cell; Colorectal cancer; Epithelial–mesenchymal transition; Filter separation