An exploration of pathways involved in lung carcinoid progression using gene expression profiling.
Pulmonary carcinoids comprise a well-differentiated subset of neuroendocrine tumors usually associated with a favorable prognosis, but mechanisms underlying disease progression are poorly understood. In an explorative approach to identify pathways associated with progression, we compared gene expression profiles of tumors from five patients with a favorable and five with a poor disease outcome. Differentially expressed genes were validated using quantitative real-time PCR on 65 carcinoid tumors, in combination with survival analysis. One of the identified pathways was further examined using immunohistochemistry. As compared with other chromosomal locations, a significantly higher number of genes downregulated in carcinoids with a poor prognosis were located at chromosome 11q (P = 0.00017), a region known to be frequently lost in carcinoids. In addition, a number of upregulated genes were found involved in the mitotic spindle checkpoint, the chromosomal passenger complex (CPC), mitotic kinase CDC2 activity and the BRCA-Fanconi anemia pathway. At the individual gene level, BIRC5 (survivin), BUB1, CD44, IL20RA, KLK12 and OTP were independent predictors of patient outcome. For survivin, the number of positive nuclei was also related to poor prognosis within the group of carcinoids. Aurora B kinase and survivin, major components of the CPC, were particularly upregulated in high-grade carcinomas and may therefore comprise therapeutic targets for these tumors. To our knowledge, this is the first expression profiling study focusing specifically on pulmonary carcinoids and progression. We have identified novel pathways underlying malignant progression and validated several genes as being strong prognostic indicators, some of which could serve as putative therapeutic targets.
Department of Molecular Cell Biology, GROW - School for Oncology & Developmental Biology, Maastricht University Medical Center, PO Box 616, 6200 MD Maastricht, The Netherlands.
Dorian R A
DR
Swarts
Leander
L
Van Neste
Mieke E R
ME
Henfling
Ivo
I
Eijkenboom
Paul P
PP
Eijk
Marie-Louise
ML
van Velthuysen
Aryan
A
Vink
Marco
M
Volante
Bauke
B
Ylstra
Wim
W
Van Criekinge
Manon
M
van Engeland
Frans C S
FC
Ramaekers
Ernst-Jan M
EJ
Speel
D000328:Adult; D000368:Aged; D002276:Carcinoid Tumor / Q000235:genetics* / Q000401:mortality / Q000473:pathology*; D043171:Chromosomal Instability / Q000235:genetics; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D018450:Disease Progression; D015536:Down-Regulation / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008938:Mitosis / Q000235:genetics; D011379:Prognosis; D015398:Signal Transduction / Q000235:genetics*; D016019:Survival Analysis; D059467:Transcriptome / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics; D055815:Young Adult