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Thirty seven N -(5-methoxyphenyl)-4-methoxybenzenesulphonamide with methoxy or/and bromo substitutions (series 1-4) and with different substituents on the sulphonamide nitrogen have been synthesised. 21 showed sub-micromolar cytotoxicity against HeLa and HT-29 human tumour cell lines, and were particularly effective against MCF7. The most potent series has 2,5-dimethoxyanilines, especially the 4-brominated compounds 23 - 25 . The active compounds inhibit microtubular protein polymerisation at micromolar concentrations, thus pointing at tubulin as the target. Co-treatment with the MDR inhibitor verapamil suggests that they are not MDR substrates. Compound 25 showed nanomolar antiproliferative potency. It severely disrupts the microtubule network in cells and arrests cells at the G 2 /M cell-cycle phase, thus confirming tubulin targeting. 25 triggered apoptotic cell death, and induced autophagy. Docking studies suggest binding in a distinct way to the colchicine site. These compounds are promising new antitumor agents acting on tubulin.

Background: An essential question in cancer is why individuals with the same disease have different clinical outcomes. Progress toward a more personalized medicine in cancer patients requires taking into account the underlying heterogeneity at different molecular levels., Results: Here, we present a model in which there are complex interactions at different cellular and systemic levels that account for the heterogeneity of susceptibility to and evolution of ERBB2-positive breast cancers. Our model is based on our analyses of a cohort of mice that are characterized by heterogeneous susceptibility to ERBB2-positive breast cancers. Our analysis reveals that there are similarities between ERBB2 tumors in humans and those of backcross mice at clinical, genomic, expression, and signaling levels. We also show that mice that have tumors with intrinsically high levels of active AKT and ERK are more resistant to tumor metastasis. Our findings suggest for the first time that a site-specific phosphorylation at the serine 473 residue of AKT1 modifies the capacity for tumors to disseminate. Finally, we present two predictive models that can explain the heterogeneous behavior of the disease in the mouse population when we consider simultaneously certain genetic markers, liver cell signaling and serum biomarkers that are identified before the onset of the disease., Conclusions: Considering simultaneously tumor pathophenotypes and several molecular levels, we show the heterogeneous behavior of ERBB2-positive breast cancer in terms of disease progression. This and similar studies should help to better understand disease variability in patient populations.

Introduction: Anthracyclines have various mechanisms of action that in the end lead to DNA double-strand breaks. Single-nucleotide polymorphisms (SNPs) in DNA repair genes may alter the protein function, affecting DNA repair proficiency and, therefore, the efficiency of DNA damaging chemotherapy. We have analysed whether SNPs in DNA repair genes (XRCC1, XRCC3 and XPD) could be useful to predict the response to anthracyclines in patients with early-stage breast cancer (EBC)., Methods: Peripheral blood samples from 150 patients with EBC were used for genotyping XRCC3Thr241Met, XRCC1Arg399Gln and XPDLys751Gln. Genotypes were correlated with survival outcomes., Results: Eighty-four patients received treatment with chemotherapy regimens containing anthracyclines. In this group, patients with XRCC1Arg399Arg had a significant improvement in 5-year Disease Free Survival (DFS) compared with those with the Arg/Gln and Gln/Gln variants (84 vs 46 %, p = 0.026). In the multivariate analysis, XRCC1Arg399Arg was reported as an independent prognostic factor for DFS (HR 0.4, CI-95 % 0.2-0.9, p = 0.035). Patients with the XRCC3 Met241Met genotype presented better 5-year OS than those carrying the Thr/Thr and Met/Thr variants (100 vs 70 %, p = 0.030). A multivariate analysis for OS confirmed the independent prognostic value of XRCC3 Met241Met (HR 0.15, CI-95 % 0.02-0.90, p = 0.048). These differences were not significant when patients receiving other chemotherapy treatments, different from anthracyclines, were also considered (n = 150). XPDLys751Lys was associated with older age at diagnosis than the Lys/Gln and Gln/Gln genotypes (65 vs 58 years, p < 0.0001)., Conclusions: XRCC3Thr241Met and XRCC1Arg399Gln may be predictive of survival outcome in EBC patients treated with anthracycline-based chemotherapy regimens.

Recently, it has been reported that biallelic mutations in the ERCC4 (FANCQ) gene cause Fanconi anemia (FA) subtype FA-Q. To investigate the possible role of ERCC4 in breast and ovarian cancer susceptibility, as occurs with other FA genes, we screened the 11 coding exons and exon-intron boundaries of ERCC4 in 1573 index cases from high-risk Spanish familial breast and ovarian cancer pedigrees that had been tested negative for BRCA1 and BRCA2 mutations and 854 controls. The frequency of ERCC4 mutation carriers does not differ between cases and controls, suggesting that ERCC4 is not a cancer susceptibility gene. Interestingly, the prevalence of ERCC4 mutation carriers (one in 288) is similar to that reported for FANCA, whereas there are approximately 100-fold more FA-A than FA-Q patients, indicating that most biallelic combinations of ERCC4 mutations are embryo lethal. Finally, we identified additional bone-fide FA ERCC4 mutations specifically disrupting interstrand cross-link repair., (© 2013 WILEY PERIODICALS, INC.)

BRCA2-c.2808&#95;2811del (3036delACAA) is one of the most reported germ line mutations in non-Ashkenazi breast cancer patients. We investigated its genetic origin in 51 Spanish carrier families that were genotyped with 11 13q polymorphic markers. Three independent associated haplotypes were clearly distinguished accounting for 23 [west Castilla y León (WCL)], 20 [east Castilla y León (ECL)] and 6 (South of Spain) families. Mutation age was estimated with the Disequilibrium Mapping using Likelihood Estimation software in a range of 45-68 and 45-71 generations for WCL and ECL haplotypes, respectively. The most prevalent variants, c.2808&#95;2811del and c.2803G > A, were located in a double-hairpin loop structure (c.2794-c.2825) predicted by Quikfold that was proposed as a mutational hotspot. To check this hypothesis, random mutagenesis was performed over a 923 bp fragment of BRCA2, and 86 DNA variants were characterized. Interestingly, three mutations reported in the mutation databases (c.2680G > A, c.2944del and c.2957dup) were replicated and 20 affected the same position with different nucleotide changes. Moreover, five variants were placed in the same hairpin loop of c.2808&#95;2811del, and one affected the same position (c.2808A > G). In conclusion, our results support that at least three different mutational events occurred to generate c.2808&#95;2811del. Other highly prevalent DNA variants, such as BRCA1-c.68&#95;69delAG, BRCA2-c.5946delT and c.8537delAG, are concentrated in hairpin loops, suggesting that these structures may represent mutational hotspots.

There are increasing data supporting the existence of a cell hierarchy within the mammary gland. At the top or this hierarchy a small population of cells with self-renewal properties maintains the tissue architecture and remodeling, and they are known as stem cells. Also, recent evidences indicate that breast cancer is originated and maintained by its own cancer stem cells reminding the normal mammary gland. The existence of this small population of cells with self-renewal capability has important biological and clinical significances. So, the interpretation of tumors as hierarchical cellular structures has changed our vision of the breast cancer scenario. Here, we review the current knowledge about normal and breast cancer stem cells, and their implications in cancer development, together with their consequences in breast cancer susceptibility, dissemination and treatment response.

Breast cancer is a first magnitude problem of public health worldwide. There is increasing evidence that this cancer is originated in and maintained by a small population of undifferentiated cells with self-renewal properties. This small population generates a more differentiated pool of cells which represents the main mass of the tumor, resembling the hierarchical tissue organization of the normal breast. These cancer stem cells seem to share a similar phenotype with their normal counterparts but they display dysfunctional patterns of proliferation and differentiation, and they no longer respond to normal physiological controls that ensure a balanced cellular turnover. The origin of these cancer stem cells is controversial; it is not well known if they are originated from normal stem cells or from more differentiated progenitors where a de novo stem cell program is activated by the oncogenic insult. Here we review the origin of breast cancer stem cells and their role in the pathogenesis of cancer development, together with their implications in breast cancer progression, treatment and prognosis.

Germline mutations in the BRCA1 and BRCA2 genes confer a high lifetime risk of developing breast and other cancers; however, remarkable differences exist regarding disease manifestation in mutation carriers. It has been suggested that other genetic and/or environmental factors modify not only the appearance but also the age of onset and type of tumor in BRCA1/2-associated cases. The aim of the present study was to investigate the role of two p53 polymorphisms (c.97-147ins16bp and c.215c>g, p.Arg72Pro) as potential modifiers. For this purpose we investigated the possible association between the two polymorphisms and disease status in 447 BRCA1/2 mutation carriers belonging to 170 Spanish breast and/or ovarian cancer families. Genotype and haplotype analyses revealed that the presence of a specific haplotype carrying the allele without the 16-bp insertion and the variant allele for the Arg72Pro (No Ins-72Pro haplotype) was associated with an earlier age of onset in BRCA2 mutation carriers. We found an increased risk of developing a first primary tumor (breast or ovarian) before 35 years of age for individuals who carried at least one No Ins-72Pro haplotype (OR: 2.69; 95% CI: 1.15-6.29; P=0.022). We confirmed these data by a functional study in which we compared different p53 genotypes in relation to their apoptotic response after cell treatment with a cytotoxic drug (AraC). Our results revealed a decrease in p53 apoptotic rate associated with the No Ins-72Pro haplotype., (2006 Wiley-Liss, Inc.)

Six SNPs have been detected in the DNA repair genes RAD51C and RAD51D, not previously characterized. The novel variant E233G in RAD51D is more highly represented in high-risk, site-specific, familial breast cancer cases that are not associated with the BRCA1/2 genes, with a frequency of 5.74% (n = 174) compared to a control population (n = 567) and another subset of breast cancer patients (n = 765) with a prevalence of around 2% only (comparison to controls, OR = 2.6, 95% CI 1.12-6.03; p < 0.021). We found that the immunohistochemical profile detected in available tumors from these patients differs slightly from those described in non-BRCA1/2 tumors. Finally, the structural prediction of the putative functional consequence of this change indicates that it can diminish protein stability and structure. This suggests a role for E233G as a low-penetrance susceptibility gene in the specific subgroup of high-risk familial breast cancer cases that are not related to BRCA1/2., (Copyright 2004 Wiley-Liss, Inc.)

We screened index cases from 410 Spanish breast/ovarian cancer families and 214 patients (19 of them males) with breast cancer for germ-line mutations in the BRCA1 and BRCA2 genes, using SSCP, PTT, CSGE, DGGE, and direct sequencing. We identified 60 mutations in BRCA1 and 53 in BRCA2. Of the 53 distinct mutations observed, 11 are novel and 12 have been reported only in Spanish families (41.5%). The prevalence of mutations in this set of families was 26.3%, but the percentage was higher in the families with breast and ovarian cancer (52.1%). The lowest proportion of mutations was found in the site-specific female breast cancer families (15.4%). Of the families with male breast cancer cases, 59.1% presented mutations in the BRCA2 gene. We found a higher frequency of ovarian cancer associated with mutations localized in the 5' end of the BRCA1 gene, but there was no association between the prevalence of this type of cancer and mutations situated in the ovarian cancer cluster region (OCCR) region of exon 11 of the BRCA2 gene. The mutations 187&#95;188delAG, 330A>G, 5236G>A, 5242C>A, and 589&#95;590del (numbered after GenBank U14680) account for 46.6% of BRCA1 detected mutations whereas 3036&#95;3039del, 6857&#95;6858del, 9254&#95;9258del, and 9538&#95;9539del (numbered after GenBank U43746) account for 56.6% of the BRCA2 mutations. The BRCA1 330A>G has a Galician origin (northwest Spain), and BRCA2 6857&#95;6858del and 9254&#95;9258del probably originated in Catalonia (northeast Spain). Knowledge of the spectrum of mutations and their geographical distribution in Spain will allow a more effective detection strategy in countries with large Spanish populations., (Copyright 2003 Wiley-Liss, Inc.)

Background: The bcl-2 gene encodes a protein that blocks apoptosis and might help to promote tumor development. It is expressed in a high percentage of breast tumors and is associated with good prognostic features. However, the mechanisms that regulate bcl-2 expression in breast carcinoma are unknown. Moreover, immunohistochemical detection of bcl-2 is related inversely to p53 expression. This notwithstanding, the immunohistochemical detection of p53 does not always correlate with the detection of p53 gene mutations. The authors studied the molecular organization of bcl-2 as well as the methylation status of its CpG island and analyzed the correlation between bcl-2 expression and p53 gene mutations., Methods: The molecular organization of the bcl-2 gene and the methylation pattern of its CpG island were analyzed by Southern blot analysis. In addition, immunohistochemical analysis of bcl-2 and p53 protein expression was performed. Finally, the presence of mutations at exons 5-9 of the p53 gene were analyzed by polymerase chain reaction and single-strand conformation polymorphism., Results: No molecular abnormality was found at the bcl-2 locus in cases of sporadic breast carcinoma. Moreover, loss of heterozygosity analysis failed to detect any allelic loss in the study cases. It also was found that the bcl-2 CpG island was demethylated in all cases. These results point to a lack of correlation between bcl-2 protein expression and the presence of p53 gene mutations., Conclusions: The level of bcl-2 expression in breast carcinoma is not associated with any somatic abnormality or epigenetic change at the bcl-2 locus. Conversely, although bcl-2 expression is related inversely to p53 protein expression, the analysis of p53 mutations (limited to exons 5-9) failed to demonstrate any relationship between p53 mutations and bcl-2 protein expression.

Background: p53 mutations constitute the most frequent genetic abnormality observed in breast cancer. The molecular study of p53 mutations not only provides prognostic information but also allows a better understanding of tumor biology. Most of the studies on p53 have been done by immunohistochemistry procedures. In this study we compare the sensitivity of immunohistochemistry and molecular genetics methods for the detection of p53 mutations., Patients and Methods: Forty tumors obtained from breast cancer patients that underwent modified radical mastectomy were analyzed for p53 mutations at exons 5 to 6 through PCR-single stranted conformational polymorphism (SSCP)-sequencing. Moreover, the tumor expression of p53 protein was analyzed by means of immunohistochemistry., Results: All tumors could be amplified by PCR and analyzed by the SSCP technique. Six tumors (15%) showed and altered electrophoretic mobility. In these cases a mutation was confirmed by gene sequencing. On the other hand, only two of these six tumors were positive in the immunohistochemical analysis., Conclusions: The results confirm the utility of the PCR-SSCP technique for detection of p53 mutations and suggest to be more sensitive than immunohistochemistry.

Metastasis is the most frequent cause of death in patients with breast cancer. The nm23-H1 and p53 genes have been involved in the development of breast cancer metastasis. We have analyzed the correlation between the expression of nm23 protein and several established clinicopathologic factors. Our results show that the antimetastatic role of nm23-H1 is not related to the cell proliferative status or tumor grade and that it is not associated with the expression of p53. We also demonstrate a strong inverse relationship between the expression of nm23-H1 protein, lymph node metastasis and vascular invasion. These data support the antimetastatic role of the nm23-H1 gene and suggest that nm23-H1 and p53 genes may be involved in different steps of the metastatic process.