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PubMed1997

p53 mutations in breast cancer: incidence and relations to tumor aggressiveness and evolution of the disease.

Breast cancer is a polymorphic disease and, until now, nodal invasion and steroid receptor levels remain the most powerful and widely used prognostic indicators. Molecular oncology has proven the importance of somatic genetic events in cancer genesis and evolution. In breast cancer a number of genetic aberrations have been proposed to bear impact on disease outcome. Greatest significance has been associated to ERBB2 amplification and overexpression. More recently p53 mutations have been suggested to bear meaning in terms of cancer evolution. We discuss here the molecular epidemiology of p53 mutations in human breast tumors and the clinico-pathological significance that can be associated to them.

Breast Neoplasms↗
PubMed1996

Clonal evolution of lung tumors.

Lung tumors, particularly squamous cell carcinomas, are believed to develop through a series of morphological abnormalities, driven by underlying somatic genetic changes. One way of studying this process is to analyze candidate somatic genetic changes in samples of squamous metaplasia and bronchial dysplasia of varying degrees of severity as well as tumor from the same patient. This assumes a clonal relationship between these lesions. In this article, we provide evidence that adjacent, physically distinct bronchial abnormalities are clonally related. This has been achieved using a plaque assay technique to detect the same p53 mutation, present throughout a tumor specimen, in a small proportion of cells in an adjacent squamous metaplasia. In addition, we have obtained two dysplasia samples from a tumor-free patient over a 9-month interval. The earlier sample had one p53 mutation, whereas the later sample has to p53 mutations on different alleles. Thus, the pattern of clonal evolution detected in the parallel samples mimics the pattern seen in longitudinal samples and supports the analysis of synchronously collected samples for the study of tumor progression.

Base Sequence↗
PubMed1998

Cytogenetic analysis of hepatoblastoma: hypothesis of cytogenetic evolution in such tumors and results of a multicentric study.

Hepatoblastoma is a rare pediatric malignant tumor of the liver. Previous cytogenetic reports are sporadic. We karyotyped nine consecutive hepatoblastomas from the Italian centers participating in a multicentric study on hepatic tumors (SIOPEL 1). Six cases showed abnormal karyotypes. The most common abnormalities were trisomies of chromosomes 2 and 20. Four cases showed abnormalities of chromosome 1. On the basis of findings, we speculate the possibility of a cytogenetic evolutive pattern of hepatoblastomas.

Child, Preschool↗
PubMed1992

[Bilateral adrenal tumoral formation. Regressive spontaneous evolution].

A case of bilateral adrenal tumoral formation associated with Addison's disease is reported, and the possible cause of this association is discussed. The short-term deleterious course of metastatic malignancies, hemopathies or severe infections when left without specific treatment, and the long-term course of our patient's tumoral pathology excluded these diagnoses. The spontaneous regression of a bilateral pseudotumoral mass was suggestive of 2 causes: haematoma or tuberculosis. Haematoma was unlikely in the absence of causal factors, and this, combined with the slow regression of the adrenals, made tuberculosis the most probable diagnosis. The few similar cases found in the literature are reviewed.

Addison Disease↗
PubMed2005

Effect of hemostasis and electrosurgery on the development and evolution of brain tumor surgery in the late 19th and early 20th centuries.

Hemostatic options available to the surgeon in the late 19th and early 20th centuries were limited. The surgical ligature was limited in value to the neurological surgeon because of the unique structural composition of brain tissue as well as the approaches and operating angles used in this type of surgery. In this manuscript the authors review the options available and the evolution of surgical hemostatic techniques and electrosurgery in the late 19th and early 20th centuries and the impact of these methods on the surgical management of tumors of the brain and its coverings.

Brain↗
PubMed1993

Alveolar soft part sarcoma. A rare tumor of unusual evolution in pediatrics.

PURPOSE: A case of alveolar soft part sarcoma of the arm with metastatic pulmonary miliaria is reported in a 12-year-old girl. RESULTS: Although the size of the metastases increased greatly and progressively for 9 years with no improvement under chemotherapy, the patient's general condition remained good. CONCLUSIONS: The course in pediatric oncology of this rare mesenchymatous tumor is very unusual; the histologic pattern is characteristic but the histogenesis remains unclear. The treatment of choice is tumoral excision. Other therapies involving secondary deposits are far from satisfactory, and the prognosis is poor because of the high rate of metastases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Update on malignant ovarian germ cell tumors.

The evolution of therapy for malignant ovarian germ cell tumors has been one of the true success stories in oncology. This article reviews the major advances in this field, with emphasis on more recent developments. During the past two decades, the nomenclature and histologic criteria for the major histologic subtypes have been standardized. Although the role of secondary debulking is uncertain, it probably has merit in selected patients. The use of second-look laparotomy should be limited as much as possible. Chemotherapeutic regimens have evolved to the current "gold standard"--the combination of bleomycin, etoposide, and cisplatin, with overall disease-free survival rates of greater than 95%. For patients with metastatic dysgerminoma, chemotherapy has replaced radiation therapy as the treatment of choice. For those few patients who do not respond to first-line therapy, the combination of vinblastine, ifosfamide, and cisplatin is the most popular regimen for the subset of platinum-sensitive tumors. For those with platinum-resistant tumors, dose intensification with autologous bone marrow rescue or Phase II drugs are being investigated. Studies on the late effects of treatment reveal that reproductive potential can be preserved in most young patients. In summary, although the progress in this field has been phenomenal, small incremental advances will continue to occur during the 1990s.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

A promoter that acquired p53 responsiveness during primate evolution.

The tumor suppressor p53 activates the transcription of human PIG3 through direct interaction with a polymorphic microsatellite sequence, (TGYCC)(n). Here, the evolution of this p53-responsive element was recapitulated. Comparison between primate species revealed that the PIG3 promoter acquired this sequence element in its full length only in Hominoidea (apes and humans), whereas the number of TGYCC repeats is far lower in monkeys. Accordingly, only the PIG3 promoters from Hominoidea respond efficiently to p53, whereas those from monkeys respond poorly or not at all. In parallel, the PIG3 gene was strongly induced by p53 in human and chimpanzee cells but was unaffected by p53 in cells derived from a common marmoset monkey. Thus, a novel p53 target gene appeared as recently as during the evolution of primates. This suggests that mechanisms of tumor suppression are subject to ongoing evolution in humans and their closest relatives.

Animals↗
PubMed2006

Rapid adaptive evolution of the tumor suppressor gene Pten in an insect lineage.

The Pten gene was initially identified in humans as a tumor suppressor. It has since been shown to play important roles in the control of cell size, cell motility, apoptosis, and organ size, and it has also been implicated in aging. Pten is highly conserved among organisms as diverse as nematodes, insects, and vertebrates. In contrast, a phylogenetic analysis by maximum likelihood of a 133-amino acid region showed an average nonsynonymous-to-synonymous rate ratio of 10.4 for Pten in the lineage leading to parasitoid wasps of the Nasonia genus, indicating very strong positive selection. A previous study identified Pten as a potential QTL candidate gene for differences in male wing size in Nasonia. Most of the amino acid replacements that occurred in the Nasonia lineage cluster in a small region of the protein surface, suggesting that they might be involved in an interaction between Pten and another protein. The phenotypic changes due to Pten are not yet known, although it is not associated with known differences in male wing size. Introgression of Pten from one species to another does affect longevity, but a causal relationship is not established.

Adaptation, Biological↗
PubMed2004

Evolution of the tumor suppressor BRCA1 locus in primates: implications for cancer predisposition.

Germ-line mutations in the BRCA1 gene predispose affected individuals to breast and ovarian cancer syndromes. In an attempt to systematically analyze a broader spectrum of genetic changes ranging from frequent exon deletions and duplications to amino acid replacements and protein truncations, we isolated and characterized full size BRCA1 homologues from a representative group of non-human primates. Our analysis represents the first comprehensive sequence comparison of primate BRCA1 loci and corresponding proteins. The comparison revealed an unusually high proportion of indels in non-coding DNA. The major force driving evolutionary changes in non-coding BRCA1 sequences was Alu-mediated rearrangements, including Alu transpositions and Alu-associated deletions, indicating that structural instability of this locus may be intrinsic in anthropoids. Analysis of the non-synonymous/synonymous ratio in coding portions of the gene revealed the presence of both conserved and rapidly evolving regions in the BRCA1 protein. Previously, a rapidly evolving region with evidence of positive evolutionary selection in human and chimpanzee had been identified only in exon 11. Here, we show that most of the internal BRCA1 sequence is variable between primates and evolved under positive selection. In contrast, the terminal regions of BRCA1, which encode the RING finger and BRCT domains, experienced negative selection, which left them almost identical between the compared primates. Distribution of the reported missense mutations, but not frameshift and nonsense mutations, is positively correlated with BRCA1 protein conservation. Finally, on the basis of protein sequence conservation, we identified missense changes that are likely to compromise BRCA1 function.

Alu Elements↗
PubMed1985

Glucagon- and PP-related peptides of intestinal L cells and pancreatic/gastric A or PP cells. Possible interrelationships of peptides and cells during evolution, fetal development and tumor growth.

The immunohistochemical detection of six distinct sequences of proglucagon and its derivatives (GRPP, glicentin, glucagon-37, glucagon-29, GLP1, GLP2 and MPGF) in both intestinal L cells and pancreatic or gastric A cells of some mammals (dog, man, guinea pig) confirms that the two cell types produce the same proglucagon molecule, although the final step of its post-translational processing differs in the two cells. Immunohistochemical and ultrastructural patterns of glucagon/glicentin cells in the pancreas of lower vertebrates and early human fetuses, as well as tumor cell studies, suggest an evolution of gastropancreatic A cells from L cells. On the contrary, the PP-related peptide PYY of intestinal L cells, and PP with its C-terminal icosapeptide extension of pancreatic PP cells, likely originate from different prohormones. Although intermediate patterns of peptide expression can be observed, including some F-type PP cells of the dog pancreas (uncinate process) and pyloric mucosa showing PYY immunoreactivity or rare PYY and/or HPP immunoreactive cells of the human rectum lacking glicentin reactivity, no obvious relationship can be established between L cells and pancreatic (F-type) PP cells. However, some evolutionary, embryogenetic and oncogenetic link may exist between L cells and human D1-type PP cells, a minor population of PP cells scattered in the pancreatic tissue of dorsal pouch origin and a major fraction of tumor PP cells.

Animals↗
PubMed1989

Model for the genetic evolution of human solid tumors.

A conceptual model is proposed for the genetic evolution of many human solid tumors that is based on the observations that cancer cells may spontaneously double their chromosome number; that cells with excessive chromosome numbers may be cytogenetically unstable, both losing chromosomes randomly during subsequent cell divisions, and often developing structural abnormalities in the chromosomes that are retained; and that some structural chromosome abnormalities may activate growth-promoting genes. The sequence of tetraploidization with chromosome loss can occur repeatedly in a given tumor. The available evidence supporting the model is reviewed. A computer simulation system that embodies these concepts is described and the model is used to generate distributions of chromosome number/cell under various simulated conditions and in a variety of simulated biological settings. A simulation of the time course of changes in chromosome number per cell that accompany the spontaneous neoplastic transformation of mouse fibroblasts in vitro is described. The best fit to the data was obtained when provision was made for the activation of at least two growth-promoting genes. The conditions for generating discrete aneuploid peaks in cytogenetic and flow cytometric studies were explored; our modeling studies suggest that the activation of a growth promoting gene is required in order to produce a discrete aneuploid peak. Our modeling studies suggest that the overrepresentation of individual oncogene-bearing chromosomes in aneuploid cell lines may require the activation of gene dose-dependent growth-promoting genes and is not likely to occur in cell lines in which at least two copies of each normal chromosome are required for cell survival. Overall, the results obtained using the model are consistent with a wide variety of flow cytometric and cytogenetic studies in human solid tumors.

Animals↗
PubMed1993

Cytogenetic evolution in primary tumors, local recurrences, and pulmonary metastases of two soft tissue sarcomas.

The karyotypic pattern at different stages of tumor development may provide information on tumor progression but few data are available regarding human solid tumors. Cytogenetic analysis was performed on the primary tumor and four lung metastases of a synovial sarcoma, and the primary tumor, two consecutive local recurrences, and six pulmonary metastases, obtained at two different occasions, of a malignant fibrous histiocytoma (MFH). Simultaneous existence of more than one cytogenetically aberrant clone was also assessed through analysis of more than one sample from the same surgical specimen. Clonal chromosome aberrations were detected in all samples from the synovial sarcoma, and in both local recurrences and five of the metastases from the MFH. All clones in both tumors were cytogenetically related. The primary synovial sarcoma tumor contained two clones, one of which was also found in the lung metastases, together with a third clone that had acquired additional aberrations. Four clones with a near-tetraploid chromosome number and complex aberrations were identified in the MFH. Likely evolutionary pathways could be deduced in both cases. In the patient with synovial sarcoma one of the pulmonary metastases, rather than the primary tumor, might well have been the source of another of the pulmonary metastases. In the MFH the cytogenetic findings indicated the presence of two co-existing lineages in the primary tumor, one giving rise to the local recurrences and one to the pulmonary metastases. Our findings show that cytogenetic analysis can be used to establish the chronologic relationships between different clones in primary tumors, local recurrences and distant metastases, to determine what genetic changes are of importance for the metastatic capability of tumor cells, and to help establish the origin of the metastatic lesions.

Chromosome Aberrations↗
PubMed2006

Echocardiographic diagnosis of carcinoid disease: exceptional evolution after ovarian tumor resection without cardiac surgery.

There are very few cases described in literature with carcinoid heart disease caused by a pure ovarian tumor. Right heart failure remains the major cause of morbidity and mortality. Cardiac surgery is the only definitive treatment when cardiac symptoms become severe but with high perioperative mortality rates. We present a 68-year-old woman with a pure ovarian carcinoid tumor complicated with heart disease alive 7 years later after ovarian resection, without valve replacement and with regression of tricuspid and pulmonary injury. Echocardiography was the diagnostic clue.

Aged↗