Patterns of ALK expression in different human cancer types

TY - JOUR

T1 - Patterns of ALK expression in different human cancer types

AU - Tennstedt, Pierre

AU - Strobel, Gundula

AU - Bölch, Charlotte

AU - Grob, Tobias

AU - Minner, Sarah

AU - Masser, Sawinee

AU - Simon, Ronald

N1 - Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

PY - 2014/6/1

Y1 - 2014/6/1

N2 - AIMS: Oncogenic gene fusions involving the anaplastic lymphoma kinase (ALK) tyrosine kinase have been identified in several haematopoietic and sporadically also in solid tumour types. Preliminary results from clinical trials suggest that patients with ALK fusion positive cancers might optimally benefit from the tyrosine kinase inhibitor crizotinib, but a comprehensive analysis of solid tumour types for ALK fusion and fusion associated expression is lacking.METHODS: In order to identify human solid cancers carrying ALK alterations, we performed real-time PCR screening of 1000 tumour samples representing 29 different tumour entities. ALK-positive samples were then transferred into a tissue microarray format and subjected to ALK break-apart fluorescence in situ hybridisation (FISH) analysis and ALK immunohistochemistry (IHC) analysis.RESULTS: ALK expression was detected by real-time PCR in 260 of 896 (29%) interpretable tumour samples. FISH analysis was successful in 189 of 260 arrayed cancers but did not detect ALK rearrangement. There was also no ALK expression detectable by IHC.CONCLUSIONS: Different levels of ALK expression can be found in various cancer types using sensitive methods like real-time PCR. However, such low-level expression is independent from oncogenic ALK fusions and cannot be detected with less-sensitive methods like IHC. ALK fusion is a rare event in human solid cancers.

AB - AIMS: Oncogenic gene fusions involving the anaplastic lymphoma kinase (ALK) tyrosine kinase have been identified in several haematopoietic and sporadically also in solid tumour types. Preliminary results from clinical trials suggest that patients with ALK fusion positive cancers might optimally benefit from the tyrosine kinase inhibitor crizotinib, but a comprehensive analysis of solid tumour types for ALK fusion and fusion associated expression is lacking.METHODS: In order to identify human solid cancers carrying ALK alterations, we performed real-time PCR screening of 1000 tumour samples representing 29 different tumour entities. ALK-positive samples were then transferred into a tissue microarray format and subjected to ALK break-apart fluorescence in situ hybridisation (FISH) analysis and ALK immunohistochemistry (IHC) analysis.RESULTS: ALK expression was detected by real-time PCR in 260 of 896 (29%) interpretable tumour samples. FISH analysis was successful in 189 of 260 arrayed cancers but did not detect ALK rearrangement. There was also no ALK expression detectable by IHC.CONCLUSIONS: Different levels of ALK expression can be found in various cancer types using sensitive methods like real-time PCR. However, such low-level expression is independent from oncogenic ALK fusions and cannot be detected with less-sensitive methods like IHC. ALK fusion is a rare event in human solid cancers.

U2 - 10.1136/jclinpath-2013-201991

DO - 10.1136/jclinpath-2013-201991

M3 - SCORING: Journal article

C2 - 24478382

VL - 67

SP - 477

EP - 481

JO - J CLIN PATHOL

JF - J CLIN PATHOL

SN - 0021-9746

IS - 6

ER -