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Ignacio Tusquets

Publications and source records attributed to Ignacio Tusquets.

6 recordsLinked to original sources
PubMed2006

The MYC oncogene in breast cancer progression: from benign epithelium to invasive carcinoma.

One hypothesis for breast cancer development suggests that breast carcinogenesis involves a progression of events leading from benign epithelium to hyperplasia (with or without atypia) to carcinoma in situ and then invasive carcinoma. The MYC gene (alias c-Myc) is a transcriptional regulator whose expression is strongly associated with cell proliferation and cell differentiation. The present study is a descriptive analysis of MYC status throughout the hypothesized stages of invasive ductal carcinoma progression. A tissue microarray (TMA) was constructed including representative selected areas (normal cells, hyperplasia, in situ carcinoma, and invasive carcinoma) from each of 15 patients. Fluorescence in situ hybridization (FISH) with the LSI c-MYC/CEN8/IgH probe was performed. Two cases displayed MYC amplification (13%), showing this amplification only in the invasive carcinoma zones selected. Five cases displayed polysomy of chromosome 8 (33%), detected only in ductal in situ and invasive zones selected. Benign lesions and normal adjacent cells were classified as normal. None of the hyperplasia specimens and normal specimens analyzed showed any alterations in MYC status or any aneusomies of chromosome 8. The presence of MYC amplification only in invasive cells suggests that the finding of MYC amplification could reflect an advanced tumor progression.

Breast Neoplasms↗
PubMed2004

Characterization of HER1 (c-erbB1) status in locally advanced breast cancer using fluorescence in situ hybridization and immunohistochemistry.

Epidermal growth factor receptor (EGFR) is a 170-kDa transmembrane glycoprotein encoded by the HER1 protooncogene, located at 7p12. This receptor is related to the pathogenesis of breast cancer. The aim of this study was to analyze the status of HER1 using fluorescence in situ hybridization (FISH) and immunohistochemistry in a series of 48 patients with locally advanced breast cancer (LABC). Before neoadjuvant chemotherapy, core biopsies were taken from patients with LABC and were processed into paraffin blocks. Biopsies were then studied using FISH with a HER1 probe (Vysis, Downers Grove, Ill., USA). They were also analyzed immunohistochemically using two different EGFR antibodies from DakoCytomation (Denmark, A/S) and from Zymed (San Francisco, Calif., USA). HER1 amplifications were not found, although 31% of the cases presented aneusomy of chromosome 7. Only 2 cases presented EGFR expression. LABC presented a low level of EGFR expression. HER1 amplification was not present in LABC, although the polysomy of chromosome 7 was a common finding.

Adult↗
PubMed2004

[Epidemiological study of the GEICAM group about breast cancer in Spain (1990-1993): El Alamo project].

BACKGROUND AND OBJECTIVE: The aim of the El Alamo project was to define the demographic and clinic characteristics, treatment and evolution of women with invasive breast cancer diagnosed in hospitals of the GEICAM group (Spanish Breast Cancer Research Group) between 1990 and 1993. PATIENTS AND METHOD: Data from 4,532 patients were included. Forms were completed according to the medical history of patients, and collected in the GEICAM scientific office, where they were added to a data base. RESULTS: 32 hospitals from 19 provinces and 11 regional communities participated in the study. Mean age of the 4,532 patients was 56.72 years, 1,428 (31.5%) were premenopausal and 2,988 (65.9%) were postmenopausal. Stage II tumors were most frequent (55.5%). Among patients with stage I, II and III at diagnosis, surgery was the first treatment in most (90.7%), radical mastectomy being the most frequent procedure performed (79.7%). 70.4% of 1941 patients with positive axillary node and 37.4% of 1,806 patients without axillary affection received adjuvant chemotherapy with or without hormone therapy. CONCLUSIONS: El Alamo project represents the largest data base on breast cancer in Spain and the results are similar to those observed in other countries such as the USA.

Adult↗
PubMedDate not supplied

Pitfalls and caveats in BRCA sequencing.

Between 5 and 10% of breast cancer cases are considered to result from hereditary predisposition. Germ-line mutations in BRCA1 and BRCA2 are responsible for an inherited predisposition of breast and ovarian cancer. Direct nucleotide sequencing is considered the gold standard technique for mutation detection for genes such as BRCA1 and BRCA2. In many laboratories that analyze BRCA1 and BRCA2, previous to direct sequencing, screening techniques to identify sequence variants in the PCR amplicons are performed. The mutations detected in these genes may be frameshift mutations (insertions or deletions), nonsense mutations, or missense mutations. The clinical interpretation of the mutation as the cause of the disease may be difficult to establish in the case of missense mutations. Only in 30-70% of the families in which a hereditary component is suspected, a mutation in BRCA1 and/or BRCA2 is detected. Negative results may be due to: wrong selection of the proband; mutations in the regulatory portion of the genes; gene silencing due to epigenetic phenomena; or large genomic rearrangements that produce deletions of whole exons. Another possibility that explains the lack of detection of alterations in BRCA1 or BRCA2 is the presence of mutations in undiscovered genes or in genes that interact with BRCA1 and/or BRCA2, which may be low-penetrance genes, like CHEK2.

Breast Neoplasms↗