Functional analysis of LOXL2 in pancreatic carcinoma.
OBJECTIVE
Lysyl oxidase-like 2 (LOXL2) plays a part in epithelial-mesenchymal transition (EMT) by stabilizing the transcription factor SNAI1. Previous studies showed that LOXL2 is one of the most highly and specifically upregulated genes in pancreatic cancer. LOXL2 was also found to be strongly upregulated in the secretome of established pancreatic cancer cell lines. To get more insight into the aggressive growth and infiltrating nature of pancreatic cancer, we evaluated the functional role of LOXL2 in pancreatic cancer cells.


METHODS
Gene inhibition by small interfering RNAs was used to silence LOXL2 in pancreatic cancer cell lines MiaPaCa-2 and Panc1. Cell death, proliferation, and morphology of transfected cells were determined. Cell characteristics under cell stress and gemcitabine treatment were analyzed. Gene expression analysis of transfected cells by DNA microarray was used to understand the processes of chemosensitization.


RESULTS
Silencing of LOXL2 in pancreatic cancer cells resulted in an augmented sensitivity toward gemcitabine treatment, with significantly elevated cell death and reduced viable cells. However, transfection had no direct effect on morphology or growth pattern of Mia PaCa-2 and Panc1 cell lines. Gene expression analysis identified among others the transcription factor E2F5 as possible target of LOXL2.


CONCLUSIONS
Gene inhibition of the EMT regulatory gene LOXL2 resulted in a distinct sensitization toward gemcitabine. Additionally, gene expression analysis showed a role for LOXL2 in the regulation of different transcription factors associated with invasion and metastasis. Our results suggest that the improved response toward chemotherapy in LOLX2-silenced pancreatic cancer cells is possibly mediated by the transcription factor E2F5.
Rückert
Felix
F
Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307, Dresden, Germany. Felix.Rueckert@uniklinikum-dresden.de
Joensson
Peer
P
Saeger
Hans-Detlev
HD
Grützmann
Robert
R
Pilarsky
Christian
C
D000594:Amino Acid Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D050700:E2F5 Transcription Factor / Q000235:genetics / Q000378:metabolism; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D055785:Gene Knockdown Techniques; D020868:Gene Silencing / Q000187:drug effects; D006801:Humans; D008648:Mesoderm / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D034741:RNA, Small Interfering / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects; D014162:Transfection; D000093542:Gemcitabine
D050700:E2F5 Transcription Factor; C092558:E2F5 protein, human; D034741:RNA, Small Interfering; D003841:Deoxycytidine; D000594:Amino Acid Oxidoreductases; C119091:LOXL2 protein, human; D000093542:Gemcitabine