Molecular Genetic Factors Research Articles

Analysis by array CGH of genomic changes associated with the progression or relapse of Wilms' tumour

Despite aggressive salvage regimens, approximately half of all children who suffer a Wilms' tumour recurrence will die of their disease. Although there are increasing data on molecular genetic prognostic factors present in the tumour at diagnosis, there is little information regarding the molecular events that occur with Wilms' tumour progression and relapse. In the present study, microarray-based comparative genomic hybridization (aCGH) analysis has been carried out on 58 Wilms' tumour samples, which included 38 untreated primary and 20 recurrent tumours. A higher degree of copy number changes was observed in the recurrent tumours (33.0% genomic clones) than in the primary tumour (21.2%). Paired analysis highlighted the acquisition of 15q gain with high levels of IGF1R expression in the tumour recurrence in two cases. The most statistically significant abnormality acquired between diagnosis and relapse was loss of 17p. One case that experienced 17p loss was classified as favourable histology at diagnosis, but exhibited diffuse anaplasia at recurrence and had a homozygous TP53 deletion. Another instructive case with a constitutional 11p13 deletion presented with bilateral tumours and suffered two subsequent recurrences in the left kidney. A somatic WT1 mutation was found only in the right kidney tumour, while the constitutional 11p13 deletion was the only abnormality detected in the initial left kidney tumour by aCGH. The two subsequent relapses in the left kidney contained an accumulation of additional genetic alterations, including an independent WT1 mutation.

Chronic Lymphocytic Leukemia: Diagnosis and Treatment

Traditionally, the goal of therapy in chronic lymphocytic leukemia (CLL) has been palliative, with first-line therapy using alkylating agents and/or involved field radiotherapy (depending on the stage of disease and sites of involvement) because of the older age of affected patients and the low rate of complete remissions (CRs) with no improvement in overall survival despite treatment. With increasing knowledge about the biology, molecular genetics, and prognostic factors of the disease, the philosophy of care for patients with CLL has evolved from palliation to aiming for a potential cure, especially in younger patients. Furthermore, multiple treatment options have emerged, including purine analogues, monoclonal antibodies, and potentially stem cell transplantation. These have been associated with higher frequencies of CRs and longer durations of responses compared to conventional chemotherapy. In addition, a subset of patients treated with chemoimmunotherapy can achieve durable CRs and molecular remissions. This may translate into improved disease-free survival and potentially a "cure." Because of the heterogeneous nature of CLL, new prognostic markers are currently being incorporated into clinical trials to determine their role in routine clinical practice. This review summarizes current therapeutic regimens that are being evaluated in patients with CLL and management of disease-related complications.

A multi-gene algorithm as predictor of response to chemo-radiotherapy in head and neck cancer

10086 Background: Chemo-radiotherapy results in clinical cure for stage III/IV head and neck cancer in approximately 40% of cases, with significant treatment-associated morbidity and mortality. Molecular genetic factors predictive of treatment outcome would clearly be of value in selection of patients with highest probability of response. We have analysed the structure and epigenetic regulation of specific genes as possible predictors of outcome to chemo-radiotherapy. The genes analyzed were: p53 (single nucleotide polymorphism (SNP) and mutation), MDM2 (SNP), Chfr (methylation), CRABP1 (methylation). Methods: 84 patients with locally advanced head and neck cancer receiving cisplatin-based chemo-radiotherapy were studied. SNP genotypes were determined by direct sequencing of DNA from normal tissue. Acquired mutations in p53 and aberrant methylation in the CpG islands of specific genes were analyzed by direct sequencing and methylation-specific PCR. Results: There were 6 treatment-related deaths in 84 patients, all occurring in cases with germ-line haplotype p53 72 Arg/Arg, MDM2 309T/T. At the time of analysis, 39/84 (46%) patients had progressed or died, with median time to progression or death = 17.3 months. Complete response was more common in patients whose genetic/epigenetic profile was p53 72 Arg/Arg wild type, MDM2 309 G/G, Chfr methylated, CRABP1 methylated, compared to the profile p53 72 Arg/Arg mutant, MDM2 309 T/T, Chfr unmethylated, CRABP1 unmethylated (91% vs 46%, log rank p = 0.002). Progression-free survival was significantly longer for patients with the profile p53 72 Arg/Arg wild type, MDM2 309 G/G, Chfr methylated, CRABP1 methylated, compared to those with p53 72 Arg/Arg mutant, MDM2 309 T/T, Chfr unmethylated, CRABP1 unmethylated (% surviving progression-free at 2 years = 74% vs 36%, p = 0.001). Overall survival was significantly longer in patients with the profile p53 72 Arg/Arg wild type, MDM2 309 G/G, Chfr methylated, CRABP1 methylated compared to those with p53 72 Arg/Arg mutant, MDM2 309 T/T, Chfr unmethylated, CRABP1 unmethylated (% surviving at 2 years = 88% vs 40%, p = 0.0004). Conclusions: Genetic and epigenetic parameters influence the toxicity and clinical outcome of chemo-radiotherapy in head and neck cancer. No significant financial relationships to disclose.

Cutaneous Melanoma: Prognostic Factors

Recent data have changed our views of prognostic factors in cutaneous melanoma. While some newer methods have yielded better prognostic information, some insights have evolved as a result of large-scale population-based analyses. We review current data on several different prognostic factors and divide these factors according to their application in localized primary melanoma or metastatic melanoma. For each prognostic factor, the level of evidence supporting its use and its applicability to clinical practice are considered. For localized primary melanoma, the dominant predictors of survival include lesion thickness, ulceration, and lymph node involvement. Factors such as age, sex, anatomic location, and satellite/in-transit lesions are important in localized melanoma. Factors currently being investigated are tumor vascularity, vascular invasion, mitotic rate, tumor regression, and tumor-infiltrating lymphocytes. For metastatic melanoma, the most important prognostic factors are site of metastases and the presence of elevated serum lactic dehydrogenase. The value of these prognostic factors to clinicians caring for melanoma patients is discussed. A better understanding of prognostic factors in cutaneous melanoma has evolved over the last decade, allowing oncologists to provide appropriate treatment for their patients. Many of the prognostic factors are interrelated. In the near future, it is expected that several molecular genetic factors will provide more insight into the prognosis of patients with melanoma.

Biology of Osteogenic Sarcoma

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. Despite significant clinical improvements over the past several decades through the use of combination chemotherapy and surgery, patients with metastatic or recurrent disease continue to have a very poor prognosis. Therefore, there is a continued need to study and understand the basic biology of osteosarcoma in order to devise more targeted and rational therapeutic strategies and ultimately to improve survival for these patients. This article reviews several aspects of osteosarcoma biology where data exist to suggest that specific pathways may play a role in the pathogenesis of this tumor. These areas include host genetic predispositions, tumor cytogenetics, molecular genetics (including the Rb, p53, RECQ helicase, and telomere pathways), and metastatic factors (ezrin, annexin 2, chemokine receptor 4, Fas/FasL pathways) that may contribute to both the initiation and the progression of tumor formation. Understanding the mechanisms of and interactions between the various molecular pathways that play a role in osteosarcoma pathogenesis may eventually lead to a more rational strategy for devising therapies targeted specifically toward these pathways.

Glutathione S‐Transferase 8‐8 Expression Is Lower in Alcohol‐Preferring Than in Alcohol‐Nonpreferring Rats

A primary focus of alcohol research is to provide novel targets for alcohol treatment by identifying genes that predispose individuals to drink alcohol. Animal models of alcoholism developed by selective breeding are invaluable tools to elucidate both the genetic nature and the underlying biological mechanisms that contribute to alcohol dependence. These selected lines (high alcohol preferring and low alcohol preferring) display phenotypic and genetic differences that can be studied to further our understanding of alcohol preference and related genetic traits. By combining molecular techniques, genetic and physiological factors that underlie the cause of alcoholism can be identified. Total gene expression analysis was used to identify genes that are differentially expressed in specific brain regions between alcohol-naive, inbred alcohol-preferring (iP) and -nonpreferring (iNP) rats. Quantitative reverse transcriptase-polymerase chain reaction, in situ hybridization, Western blot, and sequence analysis were used to further characterize rat glutathione S-transferase 8-8 (rGST 8-8). Lower expression of rGST 8-8 mRNA was observed in discrete brain regions of iP compared with iNP animals, and these expression differences were confirmed. To determine additional expression patterns of rGST 8-8, we used in situ hybridization. Rat GST 8-8 was highly expressed in hippocampus, the choroid plexus of the dorsal third ventricle and the lateral ventricle, and ependymal cells along the dorsal third ventricle and the third ventricle. Western blot analysis showed that rGST 8-8 protein levels were lower in the hippocampus and the amygdala of iP compared with iNP. A silent single-nucleotide polymorphism in the coding region and three single-nucleotide polymorphisms in the 3'-UTR were identified in the rGST 8-8 cDNA. There is regional variation of rGST 8-8 expression in the brain, at both the mRNA and protein level, and the iP strain has lower innate rGST 8-8 levels than the iNP strain in discrete brain regions.

Genetic Profile of Cumulative Mutational Damage Associated With Early Pulmonary Adenocarcinoma

To detect the possible genetic alterations characteristic of bronchioloalveolar carcinoma (BAC) and to study molecular genetic factors responsible for determining the biologic aggressiveness of pulmonary adenocarcinoma, comparative analysis of loss of heterozygosity (LOH) on 9 chromosomal regions was performed in 14 BACs and in 20 stage I adenocarcinomas (AD). The most frequently affected chromosome regions in BAC were 8q and 17p. In stage I AD, more than 60% of the cases showed LOH of 1p, 3p, 5q, 7q, 17p, and 18q loci, and LOH of 1p, 3p, 7q, and 18q was observed with greater frequency than in BAC (P < 0.05). Fractional allele loss (FAL) was significantly greater in stage I AD than in BAC (P < 0.001). In cases with microdissection of multiple sites, intratumoral heterogeneity of LOH status was observed in 73% of BAC and 94% of stage I AD, and homogeneous distribution of LOH of 9p was unique to BAC. The high FAL value was associated with a poor prognosis of BAC, but this trend did not reach statistical significance (P = 0.098). In stage I AD, no correlation was found between LOH of particular chromosomal region or FAL and clinical outcome. LOH of 1p, 3p, 7q, and 18q was associated with invasive properties of pulmonary AD and may be useful in identifying invasive adenocarcinoma when conventional histomorphological tools are not helpful.

Challenging pedigrees seen in a hereditary cancer consultation center

The clinical translation of the significance of cancer “running in families” has become a source of major contention as a result of the explosion of knowledge about cancer causality at the molecular level. At the clinical level, the increasing awareness of the familial and hereditary burden of cancer has contributed heavily to both physician and lay concern about cancer risk. Problems in interpretation of the significance of a cancer family history may arise due to a variety of factors, and even if the physician correctly diagnoses a hereditary cancer-predisposing syndrome there may still be barriers to patient compliance with surveillance and management recommendations. Our purpose is to discuss a variety of potential barriers in the diagnosis and management of patients at increased hereditary cancer risk, drawing on examples from a cohort of ∼300 families evaluated at Creighton University's Hereditary Cancer Consultation Center over 8 years. Each case was selected because of the presence of one or more clinical, pathologic, molecular genetic, psychosocial, economic, confidentiality, or insurance or employment discrimination factors that had the potential to pose an obstacle in diagnosis or in patient compliance with screening and management recommendations.

Emerging Role of P53, Bcl‐2 and Telomerase Activity in Egyptian Breast Cancer Patients

Apoptotic cell death represents an important mechanism for the precise regulation of cell numbers, and a defense mechanism against tumor cells. Both bcl-2 and mutant p53 gene products have been involved in apoptotic pathways. On the other hand, cell proliferation capacity and tumorgenesis have been controlled by telomerase. The purpose of our study is to assess the prognostic significance of additional markers implicated in apoptosis and tumorgenesis. Fifty-one fresh tissue samples of primary breast carcinoma and 26 tissue samples of benign breast lesions were included in this study. Expression of bcl-2 in cell lysates and mutant p53 protein in nuclear fraction were measured by Oncogene Science EIA procedures. Telomerase activity was analyzed using the Telomerase-PCR-ELISA based on the TRAP (telomerase repeat amplification protocol) method. On the same specimens, steroid hormone receptors (ER and PgR) were measured in cytosol fraction using Abbott EIA assays. In addition, information regarding surgical-pathological features of the tumor was obtained. Univariate and Multivariate analysis was done to identify variables predictive of poor prognosis. Significant expression of bcl-2, mutant p53 proteins and relative telomerase activity were observed in malignant cases when compared to benign ones. Univariate analysis revealed significant association in the level of both mutant p53 and relative telomerase activity with tumor size and disease recurrence. Moreover, telomerase activity was significantly expressed in late stages than early ones. Multivariate analysis revealed that bcl-2, mutant p53, telomerase activity, PgR and age were independent prognostic factors. Among a panel of molecular genetic factors investigated, mutant p53 and relative telomerase activity were strongly associated with disease recurrence; hence they exert a significant prognostic role in breast cancer.

Uveal melanoma: update and future directions

In this article the author discusses advances in the treatment of ocular melanoma over the past 25 years. However, owing to metastatic disease, patient survival has not improved. Research into molecular and cellular biology and genetic factors is needed to better understand metastasis in order to improve survival.

Intramyocellular lipids and insulin resistance.

Lipids are stored not only in adipocytes but also 'ectopically' in tissues such as muscle, liver, beta cells and others. From a metabolic perspective, intramyocellular lipids (IMCLs) have recently become a focus of interest. This review summarizes history, measurement techniques and interpretation of muscle lipid data. Problems in biopsies with the separation of those metabolically active lipid droplets in the cytoplasm of myocytes from further lipids in adipocytes are discussed as well as considerations important for analysis of correlations between IMCL content and insulin sensitivity under various circumstances. The relatively new approach to non-invasive assessment of the IMCL content by magnetic resonance spectroscopy (MRS) is described in detail and exemplary spectra from different skeletal muscle types in humans are presented. The MRS technique allows human examinations of large cohorts for a detailed assessment of the interactions among metabolic parameters such as age, measures of adiposity, hormonal and ethnic factors and insulin resistance. IMCLs are generally positively correlated with measures of obesity and negatively with insulin sensitivity. Paradoxically, physical fitness (maximal aerobic capacity) increases both IMCL content and insulin sensitivity and therefore has to be taken into account as a confounding factor. Intervention studies with MRS further allowed to elucidate the regulation of IMCL. Molecular mechanisms and potential genetic factors on IMCL regulation are discussed as well as possible mechanisms of current treatment strategies for improving insulin sensitivity.

Molecular genetic advances in semicircular canal abnormalities and sensorineural hearing loss: a report of 16 cases

Objectives The study goals were (1) to determine if the degree and pattern of semicircular canal dysmorphology and the presence or absence of a cochlea in patients with congenital sensorineural hearing loss predict audiologic outcome, severity, or the frequencies involved and (2) to review the recent advances in molecular genetics of the semicircular canals and correlate this information with audiologic and anatomic patterns seen in our series of patients Design and setting We conducted a retrospective study at a tertiary care center with a large otologic and cochlear implant service. Patients and methods The study population consisted of 16 patients with congenital sensorineural hearing loss in 28 congenitally malformed inner ears consisting of semicircular canal dysplasia or aplasia, with or without cochlear malformation. History, physical examination, computed tomography scans, and serial audiograms were reviewed. Factors analyzed included other phenotypic dysmorphology characteristic of syndromes, audiometric configuration, severity and type of hearing loss, and the presence of associated inner ear anomalies other than the vestibular system. An extensive review of the literature regarding molecular genetic factors in semicircular canal anomalies, with or without cochlear abnormalities, was performed. Results Sixteen patients (31 ears) were identified with profound sensorineural hearing loss and semicircular canal abnormalities. Only 3 patients had known syndromes, although 4 patients had other congenital anomalies. Most radiographic detectable abnormalities were bilateral. Audiograms of the patients demonstrated pure tone averages between 90 and 100 dB in the affected ears with few exceptions. No correlation was found between type and severity of malformation of either the cochlea or semicircular canals with the severity of hearing loss. There was no stepwise progression of hearing loss increasing malformation severity. Seven of the 16 patients received cochlear implants. Of these 7, 3 patients had cochlear hypoplasia and 1 patient had a common cavity deformity. Audiologic follow-up on all 7 patients revealed improvement in both speech assessment threshold and pure tone average. Presence or absence of the cochlea was not a factor in outcome after cochlear implantation. Conclusion We have assembled the largest series of patients with semicircular canal dysmorphology, with or without various cochlear abnormalities. Our study failed to correlate the type and severity of semicircular canal malformation with any specific audiologic outcome. The variation in hearing loss severity and pattern even in patients with similar bony radiographic findings must be explained by other non–radiologically detectable defects, likely abnormalities in membranous labyrinthine development. New molecular genetic discoveries have linked specific genes to the development of certain inner ear structures in mice studies. The independent development of the individual semicircular canals in relation to the cochlea and vestibule and the variability in hearing loss suggest a more complex embryologic process than merely an arrest in development as previously thought. As genetic studies are extended into humans, we will likely be able to stratify these patients by molecular defect and severity of hearing loss.

Molecular Genetic Advances in Semicircular Canal Abnormalities and Sensorineural Hearing Loss: A Report of 16 Cases

The study goals were (1) to determine if the degree and pattern of semicircular canal dysmorphology and the presence or absence of a cochlea in patients with congenital sensorineural hearing loss predict audiologic outcome, severity, or the frequencies involved and (2) to review the recent advances in molecular genetics of the semicircular canals and correlate this information with audiologic and anatomic patterns seen in our series of patients. We conducted a retrospective study at a tertiary care center with a large otologic and cochlear implant service. The study population consisted of 16 patients with congenital sensorineural hearing loss in 28 congenitally malformed inner ears consisting of semicircular canal dysplasia or aplasia, with or without cochlear malformation. History, physical examination, computed tomography scans, and serial audiograms were reviewed. Factors analyzed included other phenotypic dysmorphology characteristic of syndromes, audiometric configuration, severity and type of hearing loss, and the presence of associated inner ear anomalies other than the vestibular system. An extensive review of the literature regarding molecular genetic factors in semicircular canal anomalies, with or without cochlear abnormalities, was performed. Sixteen patients (31 ears) were identified with profound sensorineural hearing loss and semicircular canal abnormalities. Only 3 patients had known syndromes, although 4 patients had other congenital anomalies. Most radiographic detectable abnormalities were bilateral. Audiograms of the patients demonstrated pure tone averages between 90 and 100 dB in the affected ears with few exceptions. No correlation was found between type and severity of malformation of either the cochlea or semicircular canals with the severity of hearing loss. There was no stepwise progression of hearing loss increasing malformation severity. Seven of the 16 patients received cochlear implants. Of these 7, 3 patients had cochlear hypoplasia and 1 patient had a common cavity deformity. Audiologic follow-up on all 7 patients revealed improvement in both speech assessment threshold and pure tone average. Presence or absence of the cochlea was not a factor in outcome after cochlear implantation. We have assembled the largest series of patients with semicircular canal dysmorphology, with or without various cochlear abnormalities. Our study failed to correlate the type and severity of semicircular canal malformation with any specific audiologic outcome. The variation in hearing loss severity and pattern even in patients with similar bony radiographic findings must be explained by other non-radiologically detectable defects, likely abnormalities in membranous labyrinthine development. New molecular genetic discoveries have linked specific genes to the development of certain inner ear structures in mice studies. The independent development of the individual semicircular canals in relation to the cochlea and vestibule and the variability in hearing loss suggest a more complex embryologic process than merely an arrest in development as previously thought. As genetic studies are extended into humans, we will likely be able to stratify these patients by molecular defect and severity of hearing loss.

Adjuvant chemotherapy for colon cancer

Colorectal cancer is one of the most frequent cancers in the world, especially in occidental countries. The primary curative therapy is surgical resection of the tumour. Within the last 15years, appropriately powered prospective randomized trials have demonstrated that adjuvant post-operative chemotherapy should be the standard treatment for stage III cancers (node-positive disease). 5-Fluorouracil(5FU)/levamisole was used in the early 1990s but has now been replaced by 5FU/leucovorin. The recommended duration of treatment is 6 months. Combining levamisole with 5FU/leucovorin does not improve efficacy. In patients with stage II colon cancer it is still unclear whether adjuvant chemotherapy is effective. In an attempt to define groups of stage II cases that may benefit from adjuvant chemotherapy, considerable efforts have been made to determine molecular genetic factors (tumour-ploidy and mutations or alterations in oncogenes and tumour-suppressor genes). Regional therapy (particularly portal vein infusion) is one of the other therapeutic strategies still considered to be investigational. Current clinical trials are evaluating the role of non-fluorinated pyrimidine agents in an adjuvant setting.

The WHO Classification of Tumors of the Nervous System

The new World Health Organization (WHO) classification of nervous system tumors, published in 2000, emerged from a 1999 international consensus conference of neuropathologists. New entities include chordoid glioma of the third ventricle, cerebellar liponeurocytoma, atypical teratoid/rhabdoid tumor, and perineurioma. Several histological variants were added, including tanycytic ependymoma, large cell medulloblastoma, and rhabdoid meningioma. The WHO grading scheme was updated and, for meningiomas, extensively revised. In recognition of the emerging role of molecular diagnostic approaches to tumor classification, genetic profiles have been emphasized, as in the distinct subtypes of glioblastoma and the already clinically useful 1p and 19q markers for oligodendroglioma and 22q/INI1 for atypical teratoid/rhabdoid tumors. In accord with the new WHO Blue Book series, the actual classification is accompanied by extensive descriptions and illustrations of clinicopathological characteristics of each tumor type, including molecular genetic features, predictive factors, and separate chapters on inherited tumor syndromes. The 2000 WHO classification of nervous system tumors aims at being used and implemented by the neuro-oncology and biomedical research communities worldwide.

Comparison of clinicopathologic characteristics and genetic alterations between microsatellite instability-positive and microsatellite instability-negative sporadic colorectal carcinomas in patients younger than 40 years old.

Many studies have demonstrated that sporadic microsatellite instability-positive colorectal cancers share several clinicopathologic features with hereditary nonpolyposis colorectal cancers, including right-sided location, young age of onset, characteristic histomorphologic features, and a good prognosis. The aim of this study was to define distinct clinicopathologic features of sporadic microsatellite instability-positive colorectal cancers and to compare genotypic characteristics between microsatellite instability-positive and microsatellite instability-negative colorectal cancers in a young group. We analyzed 61 cases of young patients (<40 years old) with colorectal cancers for microsatellite instability at five mononucleotide and three dinucleotide repeats, loss of heterozygosity at APC and DCC, and K-ras and p53 mutations. Microsatellite instability status was correlated with molecular genetic factors and clinicopathologic parameters. Microsatellite instability positivity was detected in 19 (31.1 percent) of 61 cases. Allelic alterations in TGFbetaRII, BAX, and IGFIIR were observed exclusively in microsatellite instability-positive tumors (63.1, 26.3, and 26.3 percent, respectively). Microsatellite instability-positive tumors exhibited a lower frequency of the p53 mutation (10.5 percent) than microsatellite instability-negative tumors (47.6 percent; P < 0.05). However, microsatellite instability status was not associated with APC or DCC allelic deletion or with the K-ras mutation. Microsatellite instability-positive colorectal cancers exhibited a proclivity toward proximal location, expansive growth pattern, and large tumor size (P < 0.05). Microsatellite instability-positive colorectal cancers had lower preoperative serum carcinoembryonic antigen levels (P < 0.05), a less advanced stage at presentation (P < 0.05), and a tendency toward better prognosis (P = 0.051) than microsatellite instability-negative colorectal cancers. However, there was no difference between microsatellite instability-positive and microsatellite instability-negative colorectal cancers regarding gross features, tumor grade, and extracellular mucin production. These results suggest that sporadic microsatellite instability-positive colorectal cancers in young patients have different histomorphologic features from microsatellite instability-negative colorectal cancers and hereditary nonpolyposis colorectal cancers, some overlap of genetic alterations on multistep carcinogenesis with microsatellite instability-negative colorectal cancers, and a tendency for better prognosis.

Molecular genetic studies of the model dematiaceous pathogen Wangiella dermatitidis

AbstractThe rapidly improving molecular genetic tractability of Wangiella (Exophiala) dermatitidis significantly enhances its usefulness as a model for the more than 100 other dematiaceous (melanized) agents of human disease. Previously this model was based almost exclusively on its vegetative polymorphism, which at the simplest level is expressed as three well-characterized modes of growth (e.g., blastic, apical and isotropic) that produce myriad yeast, hyphal and sclerotic phenotypes. This cellular plasticity is important for a dematiaceous model pathogen because some are hyphal in nature but exist almost exclusively as sclerotic bodies in infected tissue, whereas others are hyphal both in nature and in tissue, and still others exist in nature predominantly as yeast, but as mixtures of yeast, hyphae and sclerotic bodies in tissue. By exploiting the polymorphism of W. dermatitidis, any phenotype of another dematiaceous pathogen can be produced for study of the regulation of its development and its contribution to pathogenicity and virulence. The coupling of this asset with the recent finding that its haploid, uninucleate yeast cell is easily transformed molecularly, and the even more recent development of systems for both random and targeted gene disruptions and for site-specific, integrative gene overexpression studies suggest that it will continue as the preferred model for the dematiaceous fungi and irrespective of the mycosis involved. The results reviewed here aim to confirm this contention, stimulate others to study this fungus, and demonstrate that W. dermatitidis is exceptionally useful for discovering by molecular genetic techniques cell wall-associated virulence factors in fungi, and in particular in the dematiaceous fungi.

Multivariate Analysis of Bcl-2, Apoptosis, P53, And Her-2/Neu In Breast Cancer: A Short Term Follow Up

Background. Several molecular genetic alterations in breast cancer, including aneuploidy, altered apoptosis, aberrant expression of p53, HER-2/neu and Bcl-2, have been associated with poor prognosis in breast cancer patients. To determine the importance of molecular-genetic factors relative to more traditional surgical- pathologic prognostic factors, multivariate analysis was performed. Materials and Methods. Ninety-four fresh tissue samples of primary breast carcinoma were studied with flow cytometry for DNA ploidy. On the same specimens steroid hormone receptors (ER and PR) were measured in the cytosol fraction using Abbott ELISA assays, HER-2/neu was determined in the membrane fraction and mutant p53 protein in the nuclear fraction, both, by Oncogene Science ELIZA procedures. Bcl-2 and apoptosis (Cell death) were measured in cell lysates by Oncogene Science & Boehringer Mannheim ELISA assays. In addition, information regarding surgical-pathological features of the tumor was obtained. Multivariate analysis using unconditional logistic regression model was done to identify variables predictive of poor prognosis. Results. Using univariate analysis, histological grade, tumor stage, lymph node status, HER-2/neu, and mutant p53, were predictive of poor short-term prognosis. By multivariate analysis, tumor stage, lymph node status, HER-2/neu were independent factors. Grade subgroup analysis versus time of relapse, illustrated a predictive value of Bcl-2 in only low-grade tumors while apoptosis was significant in high-grade type. Conclusion. Among a panel of moleculargenetic factors investigated, HER-2/neu was the most strongly predictive of poor shortterm prognosis in breast cancer. Patients with HER-2/neu positive tumors can benefit from Herceptin therapy.

Multivariate Analysis of Bcl-2, Apoptosis, P53, And Her-2/Neu In Breast Cancer: A Short Term Follow Up

Background. Several molecular genetic alterations in breast cancer, including aneuploidy, altered apoptosis, aberrant expression of p53, HER-2/neu and Bcl-2, have been associated with poor prognosis in breast cancer patients. To determine the importance of molecular-genetic factors relative to more traditional surgical- pathologic prognostic factors, multivariate analysis was performed. Materials and Methods. Ninety-four fresh tissue samples of primary breast carcinoma were studied with flow cytometry for DNA ploidy. On the same specimens steroid hormone receptors (ER and PR) were measured in the cytosol fraction using Abbott ELISA assays, HER-2/neu was determined in the membrane fraction and mutant p53 protein in the nuclear fraction, both, by Oncogene Science ELIZA procedures. Bcl-2 and apoptosis (Cell death) were measured in cell lysates by Oncogene Science & Boehringer Mannheim ELISA assays. In addition, information regarding surgical-pathological features of the tumor was obtained. Multivariate analysis using unconditional logistic regression model was done to identify variables predictive of poor prognosis. Results. Using univariate analysis, histological grade, tumor stage, lymph node status, HER-2/neu, and mutant p53, were predictive of poor short-term prognosis. By multivariate analysis, tumor stage, lymph node status, HER-2/neu were independent factors. Grade subgroup analysis versus time of relapse, illustrated a predictive value of Bcl-2 in only low-grade tumors while apoptosis was significant in high-grade type. Conclusion. Among a panel of moleculargenetic factors investigated, HER-2/neu was the most strongly predictive of poor shortterm prognosis in breast cancer. Patients with HER-2/neu positive tumors can benefit from Herceptin therapy.

Extraversion: Interaction between D2 dopamine receptor polymorphisms and parental alcoholism

Both molecular genetic factors (the D2 dopamine receptor (DRD2) and the D4 dopamine receptor (DRD4) polymorphisms) and environmental influences of living in an alcoholic or nonalcoholic home on the personality traits of Extraversion and Neuroticism were assessed in drug-naive, young adolescent boys. There were no significant main effects of genetic or environmental factors on either Neuroticism or Extraversion as measured by the Junior Eysenck Personality Inventory (JEPI). However, a significant interaction between DRD2 (but not DRD4) alleles and environmental variables was observed on Extraversion. Specifically, children with the minor alleles of the DRD2 gene showed a significantly greater Extraversion score when living in an alcoholic than in a nonalcoholic home. In contrast, children with the major alleles of the DRD2 gene showed a trend in the opposite direction. Although the results are preliminary and pending replication, they nevertheless provide the first report of a specific gene–environment interaction involving a human personality trait.