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: ["Protein", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Dexamethasone", ...], "Protein" : ["BRCA-1", ...]}. 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:

A phase-1 trial of bexarotene and denileukin diftitox in patients with relapsed or refractory cutaneous T-cell lymphoma.
Denileukin diftitox, a genetically engineered fusion protein combining the enzymatically active domains of diphtheria toxin and the full-length sequence for interleukin-2 (IL-2), efficiently targets lymphoma cells expressing the high-affinity IL-2 receptor (IL-2R) consisting of the alpha/p55/CD25, beta/p75/CD122, and gamma/p64/CD132 chains. In vitro studies demonstrated that the retinoid X receptor (RXR) retinoid, bexarotene, at biologically relevant concentrations of 10(-6) M to 10(-8) M, upregulated both the p55 and p75 subunits of the IL-2R and enhanced 5- to 10-fold the susceptibility of T-cell leukemia cells to denileukin diftitox. To determine whether this biomodulatory effect could be recapitulated in vivo, we treated 14 patients with relapsed or refractory cutaneous T-cell lymphoma with escalating doses of bexarotene (75 mg/day-300 mg/day) and denileukin diftitox (18 mcg/kg per day x 3 days every 21 days) in a phase 1 trial. Overall response was 67% (4 complete responses, 4 partial responses). Modulation of IL-2R expression was observed at or above a bexarotene dose of 150 mg/day. Four patients experienced grade 2 or 3 leukopenia, and 2 had grade 4 lymphopenia. Our results demonstrate that the combination of denileukin diftitox and bexarotene is well tolerated and that even low doses (150 mg/day) of bexarotene are capable of in vivo upregulation of CD25 expression on circulating leukemia cells.
{"Chemical": ["bexarotene"], "Protein": ["IL-2", "retinoid X receptor", "IL-2R", "CD25", "RXR", "interleukin-2", "CD122", "p75", "p64", "CD132", "p55", "IL-2 receptor"]}