A Pilot Trial to Quantify Plasma Exosomes in Colorectal Cancer Screening from the International Collaborative Study between Chile and Japan.
BACKGROUND
In Chile, a national colorectal cancer (CRC) screening program using immunochemical fecal occult blood tests and colonoscopy was started in 2012 as an international collaboration between Chile and Japan. In the present study, we quantified exosomes in the peripheral blood and evaluated the implication of the results for CRC screening.


METHODS
A total of 25 peripheral plasma samples from the participants of CRC screening in Punta Arenas, Chile, were analyzed for exosomes.


RESULTS
Plasma exosomes were obtained from 5 participants with adenocarcinoma (4 pTis and 1 pT1), 8 with high-grade adenoma, 4 with low-grade adenoma, 4 with hyperplastic polyps, and 4 with normal findings. Participants with adenocarcinoma had significantly higher amounts of plasma exosomes (2.1-3.2 fold) than participants with normal findings, hyperplastic polyps, or low-grade adenoma (p = 0.016, p = 0.0034, and p = 0.0042 respectively; Tukey's multiple comparisons test). The size of the representative lesion, the number of lesions, and the sum of those 2 factors in each participant correlated significantly with the exosome amounts (r = 0.56, r = 0.58, and r = 0.72, respectively; p < 0.01; Spearman's correlation coefficient test).


CONCLUSIONS
This pilot study demonstrated that quantification of plasma exosomes is a potential alternative screening method for detecting individuals with a high risk of colorectal malignancy.
['Kobayashi|Maki|M|', 'Kawachi|Hiroshi|H|', 'Hurtado|Claudia|C|', 'Wielandt|Ana María|AM|', 'Ponce|Alejandra|A|', 'Karelovic|Stanko|S|', 'Pasternak|Samara|S|', 'Delgado|Carlos|C|', 'Pinto|Pablo|P|', 'Carrasco|Hernan|H|', 'Ito|Takashi|T|', 'Okada|Takuya|T|', 'Tanaka|Koji|K|', 'Odagaki|Tomoyuki|T|', 'Zárate|Alejandro José|AJ|', 'Kronberg|Udo|U|', 'López-Köstner|Francisco|F|', 'Tsubaki|Masahiro|M|', 'Kawano|Tatsuyuki|T|', 'Eishi|Yoshinobu|Y|']
D000230:Adenocarcinoma D000236:Adenoma D000368:Aged D002677:Chile D003106:Colon D003113:Colonoscopy D015179:Colorectal Neoplasms D055088:Early Detection of Cancer D055354:Exosomes D005260:Female D006801:Humans D007391:International Cooperation D007564:Japan D008297:Male D008875:Middle Aged D009780:Occult Blood D010865:Pilot Projects
Plasma exosomes Colorectal cancer Screening Immunochemical fecal occult blood test Colorectal adenoma