Gene expression profiles associated with the presence of a fibrotic focus and the growth pattern in lymph node-negative breast cancer.
OBJECTIVE
A fibrotic focus, the scar-like area found in the center of an invasive breast tumor, is a prognostic parameter associated with an expansive growth pattern, hypoxia, and (lymph)angiogenesis. Little is known about the molecular pathways involved.


METHODS
Sixty-five patients were selected of whom microarray data of the tumor and H&E slides for histologic analysis were available. The growth pattern and the presence and size of a fibrotic focus were assessed. Differences in biological pathways were identified with global testing. The correlations of growth pattern and fibrotic focus with common breast cancer signatures and with clinicopathologic variables and survival were investigated.


RESULTS
Tumors with a large fibrotic focus showed activation of Ras signaling and of the hypoxia-inducible factor-1alpha pathway. Furthermore, unsupervised hierarchical cluster analysis with hypoxia- and (lymph)angiogenesis-related genes showed that hypoxia-inducible factor-1alpha, vascular endothelial growth factor A, and carbonic anhydrase 9 were overexpressed. The presence of a fibrotic focus, especially a large fibrotic focus, was associated with the basal-like subtype (P = 0.009), an activated wound-healing signature (P = 0.06), and a poor-prognosis 76-gene signature (P = 0.004). The presence of a fibrotic focus (P = 0.02) and especially of a large fibrotic focus (P = 0.004) was also associated with early development of distant metastasis.


CONCLUSIONS
Our results sustain the hypothesis that hypoxia-driven angiogenesis is essential in the biology of a fibrotic focus. Ras and Akt might play a role as downstream modulators. Our data furthermore suggest that vascular endothelial growth factor A does not only drive angiogenesis but also lymphangiogenesis in tumors with a fibrotic focus. Our data also show an association between the presence of a fibrotic focus and infaust molecular signatures.
Van den Eynden
Gert G
GG
Translational Cancer Research Group (Lab Pathology University of Antwerp/University Hospital Antwerp), Wilrijk, Belgium. vandeneyndeng@hotmail.com
Smid
Marcel
M
Van Laere
Steven J
SJ
Colpaert
Cecile G
CG
Van der Auwera
Ilse
I
Bich
Trinh Xuan
TX
van Dam
Peter
P
den Bakker
Michael A
MA
Dirix
Luc Y
LY
Van Marck
Eric A
EA
Vermeulen
Peter B
PB
Foekens
John A
JA
D000951:Antigens, Neoplasm / Q000096:biosynthesis / Q000235:genetics; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology*; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases / Q000096:biosynthesis / Q000235:genetics; D005260:Female; D005355:Fibrosis; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000096:biosynthesis / Q000235:genetics; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis / Q000235:genetics / Q000473:pathology; D008875:Middle Aged; D011379:Prognosis; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis / Q000235:genetics
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases