Lack of p21/Waf-1 expression and lymphocyte infiltration in primary ovarian cancer correlate with the somatic HLA-A2 expression
21059 Background: HLA-A2 allele is highly prevalent in Scandinavia and decreases with latitude in Europe. Similarly, ovarian cancer mortality decreases with latitude in European countries. We have previously shown that HLA-A2 is associated to a severe prognosis in serous adenocarcinoma of the ovary in stage III-IV. Others have shown that lack of p21/Waf-1 and lymphocyte infiltration in this tumour is correlated to poorer prognosis as well. Here we analyse a possible linkage between these variables. Methods: Thirty eight Swedish women with epithelial ovarian cancer were analyzed for the HLA-A genotype locus by PCR/sequence-specific oligonucleotide hybridization procedure (PCR/SSOP). Tissue slides from paraffin embedded tumour material were stained with haematoxylin and antibodies anti-p21 and -p53. Results: Twenty two patients were HLA-A2 positive. Fourteen of them (37%) lacked lymphocyte infiltration wich differed significantly from HLA-A2 negative patients (n=4, 11 %) (p=0.002). All of the HLA-A2 positive patients, with serous adenocarcinoma that showed absence of tumour lymphocyte infiltration, did not express p21/waf-1 (n=7 18 %). No cases in the HLA-A2 negative group with the same parameters were identified (p=0.009). Conclusions: These observations identify a high risk group of patients by linking together the somatic expression of HLA-A2 to the lack of lymphocyte infiltration and absence of p21/Waf-1 expression at the tumour level as prognostic negative factors. The information might have a relevant impact on the patient management.. In order to obtain a stronger power the analysis will be extended to a larger group of patients. No significant financial relationships to disclose.