u-PAR expression in cancer associated fibroblast: new acquisitions in multiple myeloma progression.

BACKGROUND: Multiple Myeloma (MM) is a B-cell malignancy in which clonal plasma cells progressively expand within the bone marrow (BM) as effect of complex interactions with extracellular matrix and a number of microenvironmental cells. Among these, cancer-associated fibroblasts (CAF) mediate crucial reciprocal signals with MM cells and are associated to aggressive disease and poor prognosis. A large body of evidence emphasizes the role of the urokinase plasminogen activator (u-PA) and its receptor u-PAR in potentiating the invasion capacity of tumor plasma cells, but little is known about their role in the biology of MM CAF. In this study, we investigated the u-PA/u-PAR axis in MM-associated fibroblasts and explore additional mechanisms of tumor/stroma interplay in MM progression. METHODS: CAF were purified from total BM stromal fraction of 64 patients including monoclonal gammopathy of undetermined significance, asymptomatic and symptomatic MM, as well as MM in post-treatment remission. Flow cytometry, Real Time PCR and immunofluorescence were performed to investigate the u-PA/u-PAR system in relation to the level of activation of CAF at different stages of the disease. Moreover, proliferation and invasion assays coupled with silencing experiments were used to prove, at functional level, the function of u-PAR in CAF. RESULTS: We found higher activation level, along with increased expression of pro-invasive molecules, including u-PA, u-PAR and metalloproteinases, in CAF from patients with symptomatic MM compared to the others stages of the disease. Consistently, CAF from active MM as well as U266 cell line under the influence of medium conditioned by active MM CAF, display higher proliferative rate and invasion potential, which were significantly restrained by u-PAR gene expression inhibition. CONCLUSIONS: Our data suggest that the stimulation of u-PA/u-PAR system contributes to the activated phenotype and function of CAF during MM progression, providing a biological rationale for future targeted therapies against MM.

miRNA profiling in serum and tissue samples to assess noninvasive biomarkers for NSCLC clinical outcome.

In NSCLC, the altered expression of some miRNAs in primary tumor tissues has been correlated with diagnosis and prognosis, while the role of circulating miRNAs as cancer biomarkers is currently emerging. MiRNA expression profile through miRNA Affymetrix array was evaluated on a training set formed by the tumor component (n = 30 NSCLC serum, n = 11/30 tumor tissues) and the control component (n = 10 healthy serum and n = 11/30 noncancerous counterparts). Statistical analyses highlighted the following: a = 55 miRNAs deregulated in tumor serum, b = 27 miRNAs deregulated in tumor tissues, and c = 2 miRNAs deregulated both in tumor serum and in tumor tissues. MiRwalk tool and enrichment pathway analyses selected some miRNAs whose target genes are correlated with the main pathways involved in NSCLC tumorigenesis. The altered expression of the selected miR-486-5p (a), miR-29c* (b), and miR-133a (c) was confirmed in the validation set (n = 40). MiR-486-5p had a higher expression in tumor serum than in tumor tissues (P = 0.004), and miR-29c* showed a lower expression in tumor tissues than in tumor serum (P < 0.001). MiR-133a had a not different expression in both tumor serum and tumor tissues (P = 0.07). The low level of miR-486-5p expression in the serum of affected patients was associated with a worse time to progression of disease (P = 0.010), and serum level of miR-486-5p was a significant prognostic indicator of NSCLC (adjusted hazard ratio = 0.179, P = 0.019). These data suggest the possibility to monitor affected patients through serum and/or tissue samples, analyzing the altered expression of specific miRNAs, in order to detect prognostic biomarkers in the NSCLC.

Validation of gefitinib effectiveness in a broad panel of head and neck squamous carcinoma cells.

Recently improved understanding of the pathogenesis of human head and neck squamous cell carcinoma (HNSCC) has led to the development of new, molecular-based therapeutic strategies, one of the more promising is the utilisation of tyrosine kinase (TK) inhibitors, targeting epidermal growth factor receptor (EGFR). In this study, we tested for gefitinib effectiveness in a broad panel of 12 newly established HNSCC cell lines, investigating its ability to reduce cell growth, to induce apoptosis and to modulate cell cycle and various EGFR pathway-related targets. Gefitinib IC50 values ranged between 0.064 and 33 microM, its capability to induce apoptosis and cell accumulation in G0/G1 phase was cell line-specific, and the main EGFR-related pathway involved in gefitinib activity was PI3K/Akt/mTor. We characterised our in vitro panel extensively, with the aim to identify predictive factors for gefitinib effectiveness; all cell lines were free of human papillomavirus infection, two were positive for Fhit expression, four expressed wild-type p53, and all of them variously expressed the other two p53 family members, p63 and p73. The comparison between the targets analysed and gefitinib effectiveness evidenced the absence of a clear relationship, excluding them as predictive factors for gefitinib efficacy. Our results confirmed the in vitro efficacy of an anti-EGFR approach, but other targets than those analysed here should be characterised in order to identify valid predictive factors for gefitinib utilisation.

BRCA1 mutations and polymorphisms in a hospital-based consecutive series of breast cancer patients from Apulia, Italy.

INTRODUCTION: Hereditary breast cancer has been partly attributed to germline mutations in the BRCA1 gene that are deleterious for BRCA1 protein activity. This paper analyzes the incidence and characteristics of detectable BRCA1 mutations and polymorphisms in a hospital-based consecutive series of breast cancer patients from southern Italy to investigate the incidence and the association of these molecular alterations with breast cancer biology and family history. METHODS: One hundred cases with familial characteristics were selected from a consecutive series of 511 patients with a first diagnosis of breast cancer. DNA from peripheral blood was screened for whole BRCA1 gene mutations utilizing dHPLC as a pre-screening analysis and automatic DNA sequencing for the identification of specific alterations. RESULTS: In the overall series of 511 patients, 100 had a family history of breast cancer and were investigated for BRCA1 mutations. Two types of BRCA1 mutations were identified, 5382insC in six cases and 4566delA in one case. The 5382insC mutation was present in two out of six cases with ovarian cancer while 4566delA in one case of male cancer. The most frequent missense polymorphisms were E1038G, P871L, K1183R in exon 11, S1613G, M1652I in exon 16 and D1778G in exon 22. Confirming what found in previous studies, patients in whom pathological BRCA1 mutations were detected had early-onset breast cancer (p=0.05), positive nodal status (p=0.05), lower ER (p=0.02) and PgR (p=0.01) content. Interestingly, the K1183R polymorphism and, less strongly, S1613G polymorphism were associated to mutational risk (K1183R: OR 0.1 p=0.03; S1613G: OR 2.7 p=0.08). CONCLUSION: Mutations in the BRCA1 gene are frequent also in our consecutive series of patients from southern Italy. An association between two detected single nucleotide polymorphisms (SNPs) and BRCA1 mutational risk was ascertained. Finally, we confirm the fact that peculiar clinical-pathological features seem to characterize patients with a family history of breast cancer and BRCA1 alterations.

Mutations spanning P53 exons 5-9 detected by non-isotopic RNAse cleavage assay and protein expression in human colon cancer.

The non-isotopic assay (NIRCA), based on the observation that RNAse is able to specifically cleave a single mismatch in RNA/RNA duplexes, has been recently proposed to detect p53 mutations. To verify the use of this method as a valid screening for P53 mutations in a routinely collected cancer series, we used this assay on 3 cases with normal and 5 cases with abnormal P53 expression detected by Western blots. In all cases, P53 exons 5-6, 7 and 8-9 regions were analyzed. There were mutations only in the five overexpressed cases: two cases showed mutations in exon 5, one between intron 6 and exon 6 and two in the region spanning exons 8 and 9. Our experience showed NIRCA to be fast, reliable and providing the ability to study long target regions in a single step, thus making this assay useful for genetic screenings.

Angiogenetic axis angiopoietins/Tie2 and VEGF in familial breast cancer.

Angiogenesis leads to the formation of blood vessels from pre-existing ones, allowing tumor growth. Vascular endothelial growth factor (VEGF) and Angiopoietins (Ang-1, Ang-2) have a pivotal role in tumor angiogenesis but few data regarding their role in hereditary breast cancer are available. The aim of the present study was to analyze Ang-1, Ang-2, tyrosine-protein kinase receptor Tie2 and VEGF expression and their correlation in a cohort of familial and sporadic breast cancers in order to verify whether the presence of germline mutations in BRCA may have a role in tumor microenvironment regulation. Tumor samples from a cohort of 41 patients with a first diagnosis and a family history of breast cancer and 19 patients with sporadic breast cancers were enrolled. The expression of Tie2, Ang-1, Ang-2 and VEGF were analyzed by quantitative real-time PCR. Patients harboring BRCA mutations had higher levels of Ang-1 (P=0.05), Ang-2 (P=0.02) and VEGF (P=0.04) mRNA compared with those without BRCA mutations (BRCAX). The same was observed in triple-negative breast cancer (TNBC). Moreover, a positive correlation between Ang-2 and VEGF was found in both the familial breast cancer group (BRCA carriers: r=0.83; P<0.0001 and BRCAX: r=0.58; P=0.008) and in TNBC (r=0.62; P=0.007). The higher levels of Ang-1, Ang-2 and VEGF mRNA found in BRCA carriers and TNBCs suggest that they could be attractive angiogenic therapeutic targets in these breast cancers.