Analysis and clinical relevance of human leukocyte antigen class I, heavy chain, and beta2-microglobulin downregulation in breast cancer.

Investigation is lacking regarding the clinical impact of human leukocyte antigen (HLA) class I downregulation in breast cancer and results are inconsistent. In this study, we investigated the expression of HLA class I, the heavy chain, and beta2-microglobulin (beta2-m) by immunohistochemistry in 67 breast carcinomas (BC) and correlated results with clinical-pathologic parameters and patient outcomes. Seventy-six percent of BC were downregulated for HLA class I, whereas downregulation of heavy chain and beta2-m was observed in 57 and 46% of BC, respectively. A significant association existed between the absence of tumor necrosis and downregulation of class I and beta2-m and between the absence of lymphovascular invasion and patient's age and downregulated class I and heavy chain, respectively. Among the lymph node-positive BC patients, a significantly improved overall survival was observed in those showing beta2-m downregulation compared with patients with normal beta2-m. This result may correlate with the role of beta2-m in regulating cancer cell growth.

Prevalence of human papillomavirus cervical infection in an Italian asymptomatic population.

BACKGROUND: In the last decade many studies have definitely shown that human papillomaviruses (HPVs) are the major cause of cervical carcinogenesis and, in the last few years, HPV testing has been proposed as a new and more powerful tool for cervical cancer screening. This issue is now receiving considerable attention in scientific and non scientific press and HPV testing could be considered the most important change in this field since the introduction of cervical cytology. This paper reports our prevalence data of HPV infection collected in the '90s, while a follow up of these patients is ongoing. METHODS: For this study we used polymerase chain reaction (PCR) to search HPV DNA sequences in cervical cell scrapings obtained from 503 asymptomatic women attending regular cervical cancer screening program in the city of Genova, Italy. All patients were also submitted to a self-administered, standardized, questionnaire regarding their life style and sexual activity. On the basis of the presence of HPV DNA sequences women were separated into two groups: "infected" and "non infected" and a statistical analysis of the factors potentially associated with the infection group membership was carried out. RESULTS: The infection rate was 15.9% and the most frequent viral type was HPV 16. CONCLUSION: Our HPV positivity rate (15.9%) was consistent to that reported by other studies on European populations.

Analysis of HLA-G expression in breast cancer tissues.

Among the different mechanisms by which cancer can elude the immune system, alterations in the expression of human leukocyte antigen (HLA) class I molecules on tumor cells may play a crucial role by impairing the HLA molecules interaction with T and natural killer (NK) cells specific receptors. More recently, aberrant expression of HLA-G has been described in different tumor tissues in addition to HLA class I downregulation. The HLA-G molecule is a nonclassical HLA class I antigen selectively expressed by trophoblast and thymic epithelial cells. Several studies reported that the HLA-G function might represent an additional mechanism of tumor immune escape, mainly inhibiting NK and cytotoxic T-cell activity. Here we report the analysis of HLA-G expression both at RNA level by reverse transcriptase-polymerase chain reaction and at protein level by Western blot and immunohistochemistry in 25 breast cancer patient tissues. The aim of this study was to elucidate the HLA-G gene expression pattern in breast tumor tissues and correlate it with HLA class I alterations. Our results demonstrated that HLA-G molecules expression was never found even in a group of patients revealing HLA class I total loss, and that HLA-G is not expressed in breast cancer tissue with a low-tumor grade (G1-G2) and minimal stromal contamination.