Examination of 12-lipoxygenase (12-LOX) as a therapeutic target in non-small cell lung cancer (NSCLC): Mechanisms controlling survival and induction of apoptosis following selective inhibition

Hdl Handle:
http://hdl.handle.net/10147/244196
Title:
Examination of 12-lipoxygenase (12-LOX) as a therapeutic target in non-small cell lung cancer (NSCLC): Mechanisms controlling survival and induction of apoptosis following selective inhibition
Authors:
Cathcart, Mary Clare; Campbell, Vikki; Gately, Kathy; Cummins, Robert; Kay, Elaine; Pidgeon, Graham P; O'Byrne, Kenneth J
Citation:
J Clin Oncol 29: 2011 (suppl; abstr 7068)
Journal:
Journal of Clinical Psychology
Issue Date:
Jun-2011
URI:
http://hdl.handle.net/10147/244196
Abstract:
Background: Platelet-type 12-LOX is an arachidonic acid metabolising enzyme resulting in the formation of 12(S)-HETE, which stimulates tumour cell adhesion, invasion and metastasis. This study aimed to examine the expression profile and role of this enzyme in NSCLC, and determine if it is a potential target for intervention. Methods: A panel of retrospective resected lung tumours was stained for 12-LOX expression by IHC. Levels of the 12-LOX metabolite, 12(S)-HETE, were examined in 50 NSCLC serum samples, and correlated with serum VEGF. A panel of NSCLC cell lines were treated with baicalein (10 uM), a selective inhibitor of 12-LOX, or 12(S)-HETE (100 ng/ml) and cell survival/proliferation examined by BrdU. Apoptosis following 12-LOX inhibition was examined by HCS and validated by FACS and DNA laddering. The effect of 12-LOX inhibition on NSCLC tumour growth and survival was examined in-vivo using an athymic nude mouse model. Gene alterations following 12-LOX inhibition in NSCLC cell lines were assessed by qPCR arrays and validated by RT-PCR. Transient transfection methods were used to examine the effects of 12-LOX overexpression in NSCLC cells. Results: 12-LOX expression was observed to a varying degree in human lung cancers of varying histological subtypes. 12(S)-HETE levels were correlated (p<0.05) with those of VEGF. Baicalein inhibited proliferation/survival in all cell lines, while 12(S)-HETE increased proliferation. 12-LOX inhibition increased apoptosis, indicated by a reduction in f-actin content and mitochondrial mass potential. Treatment with baicalein significantly reduced the growth of NSCLC tumours and increased overall survival in athymic nude mice. qPCR array data implicated a number of apoptosis/angiogenesis genes regulating these effects, including bcl-2, VEGF, integrin A2 and A4. 12-LOX overexpression resulted in an increase in VEGF secretion, confirming qPCR observations. Conclusions: 12-LOX is a survival factor/potential target in NSCLC, and correlated with angiogenic factor expression. Selective 12-LOX targeting may have clinical benefit for the future treatment.
Item Type:
Conference Poster
Language:
en

Full metadata record

DC FieldValue Language
dc.contributor.authorCathcart, Mary Clareen_GB
dc.contributor.authorCampbell, Vikkien_GB
dc.contributor.authorGately, Kathyen_GB
dc.contributor.authorCummins, Roberten_GB
dc.contributor.authorKay, Elaineen_GB
dc.contributor.authorPidgeon, Graham Pen_GB
dc.contributor.authorO'Byrne, Kenneth Jen_GB
dc.date.accessioned2012-09-17T08:43:11Z-
dc.date.available2012-09-17T08:43:11Z-
dc.date.issued2011-06-
dc.identifier.citationJ Clin Oncol 29: 2011 (suppl; abstr 7068)en_GB
dc.identifier.urihttp://hdl.handle.net/10147/244196-
dc.description.abstractBackground: Platelet-type 12-LOX is an arachidonic acid metabolising enzyme resulting in the formation of 12(S)-HETE, which stimulates tumour cell adhesion, invasion and metastasis. This study aimed to examine the expression profile and role of this enzyme in NSCLC, and determine if it is a potential target for intervention. Methods: A panel of retrospective resected lung tumours was stained for 12-LOX expression by IHC. Levels of the 12-LOX metabolite, 12(S)-HETE, were examined in 50 NSCLC serum samples, and correlated with serum VEGF. A panel of NSCLC cell lines were treated with baicalein (10 uM), a selective inhibitor of 12-LOX, or 12(S)-HETE (100 ng/ml) and cell survival/proliferation examined by BrdU. Apoptosis following 12-LOX inhibition was examined by HCS and validated by FACS and DNA laddering. The effect of 12-LOX inhibition on NSCLC tumour growth and survival was examined in-vivo using an athymic nude mouse model. Gene alterations following 12-LOX inhibition in NSCLC cell lines were assessed by qPCR arrays and validated by RT-PCR. Transient transfection methods were used to examine the effects of 12-LOX overexpression in NSCLC cells. Results: 12-LOX expression was observed to a varying degree in human lung cancers of varying histological subtypes. 12(S)-HETE levels were correlated (p<0.05) with those of VEGF. Baicalein inhibited proliferation/survival in all cell lines, while 12(S)-HETE increased proliferation. 12-LOX inhibition increased apoptosis, indicated by a reduction in f-actin content and mitochondrial mass potential. Treatment with baicalein significantly reduced the growth of NSCLC tumours and increased overall survival in athymic nude mice. qPCR array data implicated a number of apoptosis/angiogenesis genes regulating these effects, including bcl-2, VEGF, integrin A2 and A4. 12-LOX overexpression resulted in an increase in VEGF secretion, confirming qPCR observations. Conclusions: 12-LOX is a survival factor/potential target in NSCLC, and correlated with angiogenic factor expression. Selective 12-LOX targeting may have clinical benefit for the future treatment.en_GB
dc.language.isoenen
dc.titleExamination of 12-lipoxygenase (12-LOX) as a therapeutic target in non-small cell lung cancer (NSCLC): Mechanisms controlling survival and induction of apoptosis following selective inhibitionen_GB
dc.typeConference Posteren
dc.identifier.journalJournal of Clinical Psychologyen_GB
dc.description.provinceLeinsteren
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