ERN1 and ALPK1 inhibit differentiation of bi-potential tumor-initiating cells in human breast cancer.
Cancers are heterogeneous by nature. While traditional oncology screens commonly use a single endpoint of cell viability, altering the phenotype of tumor-initiating cells may reveal alternative targets that regulate cellular growth by processes other than apoptosis or cell division. We evaluated the impact of knocking down expression of 420 kinases in bi-lineage triple-negative breast cancer (TNBC) cells that express characteristics of both myoepithelial and luminal cells. Knockdown of ERN1 or ALPK1 induces bi-lineage MDA-MB-468 cells to lose the myoepithelial marker keratin 5 but not the luminal markers keratin 8 and GATA3. In addition, these cells exhibit increased β-casein production. These changes are associated with decreased proliferation and clonogenicity in spheroid cultures and anchorage-independent growth assays. Confirmation of these assays was completed in vivo, where ERN1- or ALPK1-deficient TNBC cells are less tumorigenic. Finally, treatment with K252a, a kinase inhibitor active on ERN1, similarly impairs anchorage-independent growth of multiple breast cancer cell lines. This study supports the strategy to identify new molecular targets for types of cancer driven by cells that retain some capacity for normal differentiation to a non-tumorigenic phenotype. ERN1 and ALPK1 are potential targets for therapeutic development.
Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.
Juliane
J
Strietz
Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.|German Cancer Research Center (DKFZ), Heidelberg, Germany.
Stella S
SS
Stepputtis
Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.|German Cancer Research Center (DKFZ), Heidelberg, Germany.
Bogdan-Tiberius
BT
Preca
Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.|German Cancer Research Center (DKFZ), Heidelberg, Germany.
Corinne
C
Vannier
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Mihee M
MM
Kim
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
David J
DJ
Castro
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Qingyan
Q
Au
German Cancer Research Center (DKFZ), Heidelberg, Germany.|Systems Biology of the Cellular Microenvironment at The DKFZ Partner Site Freiburg, German Cancer Consortium (DKTK), Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany.
Melanie
M
Boerries
German Cancer Research Center (DKFZ), Heidelberg, Germany.|Systems Biology of the Cellular Microenvironment at The DKFZ Partner Site Freiburg, German Cancer Consortium (DKTK), Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany.
Hauke
H
Busch
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Pedro
P
Aza-Blanc
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Susanne
S
Heynen-Genel
Department of Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany.|German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.|Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Peter
P
Bronsert
Technische Universitaet Muenchen, Partner Site of the German Cancer Consortium, Freising, Germany.
Bernhard
B
Kuster
Department of OBGYN, University Clinic Aachen (UKA), Aachen, Germany.
Elmar
E
Stickeler
Department of Experimental Medicine I, University of Erlangen-Nuernberg, Erlangen, Germany.
Thomas
T
Brabletz
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Robert G
RG
Oshima
Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany.
Jochen
J
Maurer
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002227:Carbazoles / Q000494:pharmacology; D002364:Caseins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004305:Dose-Response Relationship, Drug; D004722:Endoribonucleases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D026121:Indole Alkaloids / Q000494:pharmacology; D053555:Keratin-5 / Q000235:genetics / Q000378:metabolism; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D010641:Phenotype; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D015398:Signal Transduction; D013997:Time Factors; D014162:Transfection; D064726:Triple Negative Breast Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D047368:Tumor Burden
D000970:Antineoplastic Agents; D002227:Carbazoles; D002364:Caseins; D026121:Indole Alkaloids; C503940:KRT5 protein, human; D053555:Keratin-5; D047428:Protein Kinase Inhibitors; C049985:staurosporine aglycone; D011494:Protein Kinases; C528229:ERN1 protein, human; D017346:Protein Serine-Threonine Kinases; D004722:Endoribonucleases
ALPK1; ERN1; differentiation therapy; human bi-potential tumor-initiating cells; kinase knockdown