You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Apoptosis of human breast cancer cells induced by microencapsulated betulinic acid from sour jujube fruits through the mitochondria transduction pathway. Betulinic acid (BA), a natural pentacyclic triterpenoid, was isolated from sour jujube fruits for the first time. An inclusion complex comprising BA and β-cyclodextrin (β-CD) was formed to improve the dissolution of BA, but little is known about its anticancer effect. In this study, the anti-proliferative and apoptosis mechanisms of BA-β-CD on human breast cancer MCF-7 cells were further investigated. Experimental results confirmed that the complexation model inhibited the growth of MCF-7 cells in a dose-dependent manner, arrested cell cycle in the G2/M phase and induced apoptosis via the mitochondria transduction pathway. Gene and protein analyses showed that the complexation model significantly inhibited Bcl-2 expression and promoted Bax expression, causing caspase-3 and caspase-9 cascade activation. These findings corroborated evidence on microencapsulated BA as an apoptosis inducer in MCF-7 cells. Thus, sour jujube fruits may have potential use as a breast cancer chemotherapeutic agent.
{"Chemical": ["BA-\u03b2-CD", "pentacyclic triterpenoid", "\u03b2-cyclodextrin", "\u03b2-CD", "betulinic acid", "Betulinic acid"]}