The present invention relates to vesicles derived from Acinetobacter bacteria and a use thereof. The present inventors have confirmed experimentally that vesicles are significantly reduced in clinical samples derived from patients with malignant diseases such as gastric cancer, colorectal cancer, breast cancer, ovarian cancer, and bladder cancer, cardiovascular diseases such as myocardial infarction, cardiomyopathy, and stroke, diabetes mellitus, dementia, and Parkinson disease compared to a normal person, and the vesicles significantly inhibit secretion of an inflammatory mediator by pathogenic vesicles. The present inventors have confirmed that the vesicles have an anticancer effect in a mouse cancer model. Therefore, vesicles derived from Acinetobacter bacteria according to the present invention may be effectively used for developing a diagnostic method for malignant diseases such as gastric cancer, colorectal cancer, breast cancer, ovarian cancer, and bladder cancer, cardiovascular diseases such as myocardial infarction, cardiomyopathy, and stroke, diabetes mellitus, dementia, and Parkinson disease, and for developing a composition for preventing or treating the above-mentioned diseases or inflammatory diseases.La présente invention concerne des vésicules issues de bactéries Acinetobacter et une utilisation associée. Les présents inventeurs ont confirmé expérimentalement que les vésicules sont significativement réduites dans des échantillons cliniques dérivés de patients atteints de maladies malignes telles que le cancer gastrique, le cancer colorectal, le cancer du sein, le cancer de l'ovaire et le cancer de la vessie, des maladies cardiovasculaires telles que l'infarctus du myocarde, la cardiomyopathie et l'accident vasculaire cérébral, le diabète sucré, la démence et la maladie de Parkinson par rapport à celle d'une personne normale, et que les vésicules inhibent significativement la sécrétion d'un médiateur inflammatoire par les vésicules pathogènes. Les pré
