title: Methylisoindigo preferentially kills cancer stem cells by interfering cell metabolism via inhibition of LKB1 and activation of AMPK in PDACs.
abstract: Pancreatic ductal adenocarcinoma (PDAC) clinically has a very poor prognosis. No small molecule is available to reliably achieve cures. Meisoindigo is chemically related to the natural product indirubin and showed substantial efficiency in clinical chemotherapy for CML in China. However, its effect on PDAC is still unknown. Our results showed strong anti-proliferation effect of meisoindigo on gemcitabine-resistant PDACs. Using a recently established primary PDAC cell line, called Jopaca-1 with a larger CSCs population as model, we observed a reduction of CD133+ and ESA+/CD44+/CD24+ populations upon treatment and concomitantly a decreased expression of CSC-associated genes, and reduced cellular mobility and sphere formation. Investigating basic cellular metabolic responses, we detected lower oxygen consumption and glucose uptake, while intracellular ROS levels increased. This was effectively neutralized by the addition of antioxidants, indicating an essential role of the cellular redox balance. Further analysis on energy metabolism related signaling revealed that meisoindigo inhibited LKB1, but activated AMPK. Both of them were involved in cellular apoptosis. Additional in situ hybridization in tissue sections of PDAC patients reproducibly demonstrated co-expression and -localization of LKB1 and CD133 in malignant areas. Finally, we detected that CD133+/CD44+ were more vulnerable to meisoindigo, which could be mimicked by LKB1 siRNAs. Our results provide the first evidence, to our knowledge, that LKB1 sustains the CSC population in PDACs and demonstrate a clear benefit of meisoindigo in treatment of gemcitabine-resistant cells. This novel mechanism may provide a promising new treatment option for PDAC.
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: x.cheng@uni-heidelberg.de.
authors.forename: Xinlai
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: J.Kim@uni-heidelberg.de.
authors.forename: Jee Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: shahrouzghafoory@yahoo.com.
authors.forename: Shahrouz
authors.initials: S
authors.lastname: Ghafoory
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: tijenduvaci@gmail.com.
authors.forename: Tijen
authors.initials: T
authors.lastname: Duvaci
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: roya.rafie@gmail.com.
authors.forename: Roya
authors.initials: R
authors.lastname: Rafiee
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: jannick.theobald@gmail.com.
authors.forename: Jannick
authors.initials: J
authors.lastname: Theobald
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: Hamed.alborzinia@uni-heidelberg.de.
authors.forename: Hamed
authors.initials: H
authors.lastname: Alborzinia
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: Holenya@stud.uni-heidelberg.de.
authors.forename: Pavlo
authors.initials: P
authors.lastname: Holenya
authors.affiliation: Functional Genome Analysis, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. Electronic address: J.Fredelbohm@dkfz.de.
authors.forename: Johannes
authors.initials: J
authors.lastname: Fredebohm
authors.affiliation: Department of Chemistry, Division of Food Chemistry and Toxicology, University of Kaiserslautern, Erwin-Schrödinger-Str. 52, D-67663 Kaiserslautern, Germany. Electronic address: khmerz@rhrk.uni-kl.de.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Merz
authors.affiliation: Department of General, Visceral and Transplantation Surgery, Heidelberg University, Germany. Electronic address: arianeb.mehrabi@med.uni-heidelberg.de.
authors.forename: Arianeb
authors.initials: A
authors.lastname: Mehrabi
authors.affiliation: Department of General, Visceral and Transplantation Surgery, Heidelberg University, Germany. Electronic address: mohammadreza.hafezi@med.uni-heidelberg.de.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Hafezi
authors.affiliation: Department of General, Visceral and Transplantation Surgery, Heidelberg University, Germany. Electronic address: arash.saffari@med.uni-heidelberg.de.
authors.forename: Arash
authors.initials: A
authors.lastname: Saffari
authors.affiliation: Department of Chemistry, Division of Food Chemistry and Toxicology, University of Kaiserslautern, Erwin-Schrödinger-Str. 52, D-67663 Kaiserslautern, Germany. Electronic address: eisenbra@rhrk.uni-kl.de.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Eisenbrand
authors.affiliation: Functional Genome Analysis, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. Electronic address: J.Hoheisel@dkfz-heidelberg.de.
authors.forename: Jörg D
authors.initials: JD
authors.lastname: Hoheisel
authors.affiliation: Institute of Pharmacy and Molecular Biotechnology, Pharmaceutical Biology, Heidelberg University, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany. Electronic address: wolfl@uni-hd.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Wölfl
mesh_terms: D000091162:AMP-Activated Protein Kinase Kinases; D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D021441:Carcinoma, Pancreatic Ductal / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D014411:Neoplastic Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010179:Pancreas / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000093542:Gemcitabine
chemical_list: D000970:Antineoplastic Agents; D007211:Indoles; D003841:Deoxycytidine; C047330:N-methylisoindigotin; D017346:Protein Serine-Threonine Kinases; C109790:STK11 protein, human; D000091162:AMP-Activated Protein Kinase Kinases; D055372:AMP-Activated Protein Kinases; D000093542:Gemcitabine
keywords: AMPK activation; CD133; CSC drug; Indirubin; LKB1 inactivation; Meisoindigo; PDAC; Pancreatic cancer stem cell