title: Association of mitotane with chylomicrons and serum lipoproteins: practical implications for treatment of adrenocortical carcinoma.
abstract: OBJECTIVE
  Oral mitotane (o,p'-DDD) is a cornerstone of medical treatment for adrenocortical carcinoma (ACC).
  
  
  OBJECTIVE
  Serum mitotane concentrations >14  mg/l are targeted for improved efficacy but not achieved in about half of patients. Here we aimed at a better understanding of intestinal absorption and lipoprotein association of mitotane and metabolites o,p'-dichlorodiphenylacetic acid (o,p'-DDA) and o,p'-dichlorodiphenyldichloroethane (o,p'-DDE).
  
  
  METHODS
  Lipoproteins were isolated by ultracentrifugation from the chyle of a 29-year-old patient and serum from additional 14 ACC patients treated with mitotane. HPLC was applied for quantification of mitotane and metabolites. We assessed NCI-H295 cell viability, cortisol production, and expression of endoplasmic reticulum (ER) stress marker genes to study the functional consequences of mitotane binding to lipoproteins.
  
  
  RESULTS
  Chyle of the index patient contained 197  mg/ml mitotane, 53  mg/ml o,p'-DDA, and 51  mg/l o,p'-DDE. Of the total mitotane in serum, lipoprotein fractions contained 21.7±21.4% (VLDL), 1.9±0.8% (IDL), 8.9±5.5% (LDL1), 18.9±9.6% (LDL2), 10.1±4.0% (LDL3), and 26.3±13.0% (HDL2). Only 12.3±5.5% were in the lipoprotein-depleted fraction.
  
  
  CONCLUSIONS
  Mitotane content of lipoproteins directly correlated with their triglyceride and cholesterol content. O,p'-DDE was similarly distributed, but 87.9±4.2% of o,p'-DDA found in the HDL2 and lipoprotein-depleted fractions. Binding of mitotane to human lipoproteins blunted its anti-proliferative and anti-hormonal effects on NCI-H295 cells and reduced ER stress marker gene expression.
  
  
  CONCLUSIONS
  Mitotane absorption involves chylomicron binding. High concentrations of o,p'-DDA and o,p'-DDE in chyle suggest intestinal mitotane metabolism. In serum, the majority of mitotane is bound to lipoproteins. In vitro, lipoprotein binding inhibits activity of mitotane suggesting that lipoprotein-free mitotane is the therapeutically active fraction.
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Kroiss_M@ukw.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Kroiss
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Plonné
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kendl
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Schirmer
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Cristina L
authors.initials: CL
authors.lastname: Ronchi
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schirbel
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Zink
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Constantin
authors.initials: C
authors.lastname: Lapa
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Hartwig
authors.initials: H
authors.lastname: Klinker
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Fassnacht
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Heinz
authors.affiliation: Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany.
authors.forename: Silviu
authors.initials: S
authors.lastname: Sbiera
mesh_terms: D000306:Adrenal Cortex Neoplasms / Q000188:drug therapy*; D018268:Adrenocortical Carcinoma / Q000188:drug therapy*; D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D002913:Chyle / Q000737:chemistry; D002914:Chylomicrons / Q000378:metabolism*; D015331:Cohort Studies; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects; D005260:Female; D065569:Gastrointestinal Absorption; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism* / Q000494:pharmacology; D053439:Lipoproteins, HDL2 / Q000378:metabolism; D053419:Lipoproteins, IDL / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000378:metabolism; D008079:Lipoproteins, VLDL / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D008939:Mitotane / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D018931:Antineoplastic Agents, Hormonal; D002914:Chylomicrons; D008074:Lipoproteins; D053439:Lipoproteins, HDL2; D053419:Lipoproteins, IDL; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; C054917:2,2-(2-chlorophenyl-4'-chlorophenyl)acetic acid; D008939:Mitotane; C054919:2,2-(2-chlorophenyl-4'-chlorophenyl)-1,1-dichloroethene