Prognostic and diagnostic relevance of hnRNP A2/B1, hnRNP B1 and S100 A2 in non-small cell lung cancer.
BACKGROUND
S100 A2 and hnRNP A2/B1 (heterogeneous ribonucleoprotein A2/B1) with its splicing variant hnRNP B1 are proteins which are involved in cellular proliferation, differentiation and protein synthesis and are up-regulated in non-small cell lung cancer (NSCLC). Since previous studies using paraffin-embedded tissues indicated a high potential of these markers for diagnosis and screening the present analysis intended to validate these data applying cryostat sections.


METHODS
78 tumor-infiltrated lung cancer specimens and 66 adjacent histologically tumor-free tissues were analyzed; 11 autopsy specimens from patients who did not suffer from a malignant disease served as a control group. Cryostat sections were stained with monoclonal antibodies against hnRNP A2/B1, hnRNP B1 and S100 A2 and were compared with the previously established immunohistochemical profile of the same patients including EGFR, EGFRvIII, pEGFR, c-erbB-2, c-erbB-3, p53, Ki-67, bcl-2, p120 and microvessel density. Furthermore, these results were correlated with clinical parameters.


RESULTS
Expression of hnRNP A2/B1, hnRNP B1 and S100 A2 was increased in the tumor group when compared with the microscopic tumor-free specimens in 10% versus 5% (n.s.), 91% versus 5% and 65% versus 6%, respectively. Increased S100 and A2 hnRNP A2/B1 expressions were negative prognostic factors. With the exception of an increased EGFR expression in hnRNP A2/B1 negative cases the three analyzed markers did not correlate with the immunohistochemical parameters tested previously.


CONCLUSIONS
Comparison between tumor probes and tumor-free specimens of NSCLC patients failed to approve the diagnostic relevance of hnRNP A2/B1 shown in previous studies, whereas hnRNP B1 revealed a high tumor specificity that could be helpful for tumor cell screening. Moreover, S100 A2 and hnRNP A2/B1 confirmed to be valuable prognostic parameters.
Zech
Veronika F E
VF
Department of Internal Medicine, Division of General Internal Medicine, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria.
Dlaska
Margit
M
Tzankov
Alexandar
A
Hilbe
Wolfgang
W
D000328:Adult; D000368:Aged; D001344:Autopsy; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000473:pathology; D002630:Chemotactic Factors / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D009418:S100 Proteins / Q000378:metabolism*; D015996:Survival Rate
D014408:Biomarkers, Tumor; D002630:Chemotactic Factors; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D012333:RNA, Messenger; D009418:S100 Proteins; C098997:S100A2 protein, human; C439768:hnRNP A2