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1.
Lancet Reg Health Am ; 38: 100863, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39258234

ABSTRACT

Background: Adrenocortical tumours (ACT) in children are part of the Li-Fraumeni cancer spectrum and are frequently associated with a germline TP53 pathogenic variant. TP53 p.R337H is highly prevalent in the south and southeast of Brazil and predisposes to ACT with low penetrance. Thus, we aimed to investigate whether genetic variants exist which are associated with an increased risk of developing ACT in TP53 p.R337H carrier children. Methods: A genetic association study was conducted in trios of children (14 girls, 7 boys) from southern Brazil carriers of TP53 p.R337H with (n = 18) or without (n = 3) ACT and their parents, one of whom also carries this pathogenic variant (discovery cohort). Results were confirmed in a validation cohort of TP53 p.R337H carriers with (n = 90; 68 girls, 22 boys) or without ACT (n = 302; 165 women, 137 men). Findings: We analysed genomic data from whole exome sequencing of blood DNA from the trios. Using deep learning algorithms, according to a model where the affected child inherits from the non-carrier parent variant(s) increasing the risk of developing ACT, we found a significantly enriched representation of non-coding variants in genes involved in the cyclic AMP (cAMP) pathway known to be involved in adrenocortical tumorigenesis. One among those variants (rs2278986 in the SCARB1 gene) was confirmed to be significantly enriched in the validation cohort of TP53 p.R337H carriers with ACT compared to carriers without ACT (OR 1.858; 95% CI 1.146, 3.042, p = 0.01). Interpretation: Profiling of the variant rs2278986 is a candidate for future confirmation and possible use as a tool for ACT risk stratification in TP53 p.R337H carriers. Funding: Centre National de la Recherche Scientifique (CNRS), Behring Foundation, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).

2.
Cancers (Basel) ; 14(12)2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35740610

ABSTRACT

Counselling and genetic testing (CGT) after neonatal screening may increase depression and anxiety (DA) levels during cancer surveillance. This study assessed the DA scores in mothers of newborns from Paraná state, Southern Brazil, carrying the TP53 p.R337H variant. To understand and adjust DA conditions during term of pregnancy, we initially detected sociodemographic covariates [marital status (MS), number of children (NC), and/or education level (EL): MS-NC-EL] on an independent group of pregnant women (not subjected to genetic testing). The Hospital Anxiety and Depression Scale (HADS) was used to assess risk factors in pregnant (cross-sectional analysis) and unrelated mothers (at 2-month intervals, longitudinal study) of TP53 p.R337H-tested newborns (three sessions of HADS analysis) using Wilcoxon (Mann-Whitney) and Kruskal-Wallis nonparametric tests. Lower anxiety levels were observed in mothers of noncarriers (without MS-NC-EL = 6.91 ± 1.19; with MS-NC-EL = 6.82 ± 0.93) than in mothers of p.R337H carriers in the first session (without MS-NC-EL = 6.82 = 8.49 ± 0.6025, with MS-NC-EL = 6.82 = 9.21 ± 0.66). The anxiety levels significantly decreased 4 months after CGT (third session) in mothers of p.R337H carriers. We did not find a significant change in depression scores. Mothers with mental health instability requiring medications need periodical psychological support during and after CGT.

3.
Cancers (Basel) ; 14(12)2022 Jun 19.
Article in English | MEDLINE | ID: mdl-35740679

ABSTRACT

Two major concerns associated with cancer development in Paraná state, South Brazil, are environmental pollution and the germline TP53 p.R337H variant found in 0.27−0.30% of the population. We assessed breast cancer (BC) risk in rural (C1 and C2) and industrialized (C3) subregions, previously classified by geochemistry, agricultural productivity, and population density. C2 presents lower organochloride levels in rivers and lower agricultural outputs than C1, and lower levels of chlorine anions in rivers and lower industrial activities than C3. TP53 p.R337H status was assessed in 4658 women aged >30 years from C1, C2, and C3, subsequent to a genetic screening (Group 1, longitudinal study). BC risk in this group was 4.58 times higher among TP53 p.R337H carriers. BC prevalence and risk were significantly lower in C2 compared to that in C3. Mortality rate and risk associated with BC in women aged >30 years (n = 8181 deceased women; Group 2) were also lower in C2 than those in C3 and C1. These results suggest that environmental factors modulate BC risk and outcome in carriers and noncarriers.

4.
Cancers (Basel) ; 13(23)2021 Dec 03.
Article in English | MEDLINE | ID: mdl-34885220

ABSTRACT

The incidence of pediatric adrenocortical tumors (ACT) is high in southern Brazil due to the founder TP53 R337H variant. Neonatal screening/surveillance (NSS) for this variant resulted in early ACT detection and improved outcomes. The medical records of children with ACT who did not participate in newborn screening (non-NSS) were reviewed (2012-2018). We compared known prognostic factors between the NSS and non-NSS cohorts and estimated surveillance and treatment costs. Of the 16 non-NSS children with ACT carrying the R337H variant, the disease stages I, II, III, and IV were observed in five, five, one, and five children, respectively. The tumor weight ranged from 22 to 608 g. The 11 NSS children with ACT all had disease stage I and were alive. The median tumor weight, age of diagnosis, and interval between symptoms and diagnosis were 21 g, 1.9 years, and two weeks, respectively, for the NSS cohort and 210 g, 5.2 years, and 15 weeks, respectively, for the non-NSS cohort. The estimated surveillance/screening cost per year of life saved is US$623/patient. NSS is critical for improving the outcome of pediatric ACT in this region. Hence, we strongly advocate for the inclusion of R337H in the state-mandated universal screening and surveillance.

5.
Diagnosis (Berl) ; 8(4): 510-514, 2021 11 25.
Article in English | MEDLINE | ID: mdl-32857713

ABSTRACT

OBJECTIVES: The differential diagnosis between acute bacterial meningitis (BM) and viral meningitis (VM) is crucial for treatment and prognosis. Cerebrospinal fluid (CSF) lactate (LA) is considered a good biomarker for differentiating BM from VM. The objective of this study was to compare the clinical performance of amperometry, which is not validated for measurement of LA in CSF samples, with a validated method (enzymatic ultra violet), for their ability to discriminate between acute BM and VM. METHODS: It was a retrospective, descriptive comparative study, 320 CSF reports were included; LA was quantified in CSF using either Dimension AR machine (Dade Behring) or amperometry (RAPID Point 500, Siemens). All samples with bacteria (n=54) or virus (n=139) identified, compared with a control with normal CSF (n=127). RESULTS: CSF LA levels were comparable for amperometry or enzymatic methods on each group studied, in a wide range of LA levels; it was capable to distinguish BM from VM independent of the method used to quantify. CONCLUSIONS: The findings support the use of the amperometric method in measuring LA concentrations in CSF in a wide range of values. Amperometry is a less expensive method, validated for blood, easily available in small laboratories including in limited resources countries.


Subject(s)
Meningitis, Bacterial , Meningitis, Viral , Biomarkers , Humans , Lactic Acid , Meningitis, Bacterial/diagnosis , Retrospective Studies
6.
Endocr Connect ; 9(12): 1212-1220, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33112833

ABSTRACT

OBJECTIVE: Adaptive changes in DHEA and sulfated-DHEA (DHEAS) production from adrenal zona reticularis (ZR) have been observed in normal and pathological conditions. Here we used three different cohorts to assess timing differences in DHEAS blood level changes and characterize the relationship between early blood DHEAS reduction and cell number changes in women ZR. MATERIALS AND METHODS: DHEAS plasma samples (n = 463) were analyzed in 166 healthy prepubertal girls before pubarche (<9 years) and 324 serum samples from 268 adult females (31.9-83.8 years) without conditions affecting steroidogenesis. Guided by DHEAS blood levels reduction rate, we selected the age range for ZR cell counting using DHEA/DHEAS and phosphatase and tensin homolog (PTEN), tumor suppressor and cell stress marker, immunostaining, and hematoxylin stained nuclei of 14 post-mortem adrenal glands. RESULTS: We confirmed that overweight girls exhibited higher and earlier DHEAS levels and no difference was found compared with the average European and South American girls with a similar body mass index (BMI). Adrenopause onset threshold (AOT) defined as DHEAS blood levels <2040 nmol/L was identified in >35% of the females >40 years old and associated with significantly reduced ZR cell number (based on PTEN and hematoxylin signals). ZR cell loss may in part account for lower DHEA/DHEAS expression, but most cells remain alive with lower DHEA/DHEAS biosynthesis. CONCLUSION: The timely relation between significant reduction of blood DHEAS levels and decreased ZR cell number at the beginning of the 40s suggests that adrenopause is an additional burden for a significant number of middle-aged women, and may become an emergent problem associated with further sex steroids reduction during the menopausal transition.

7.
Cancers (Basel) ; 11(11)2019 Nov 16.
Article in English | MEDLINE | ID: mdl-31744167

ABSTRACT

The TP53 R337H mutation is associated with increased incidence of pediatric adrenocortical tumor (ACT). The different environmental conditions where R337H carriers live have not been systematically analyzed. Here, the R337H frequencies, ACT incidences, and R337H penetrance for ACT were calculated using the 2006 cohort with 4165 R337H carriers living in Paraná state (PR) subregions. The effectiveness of a second surveillance for R337H probands selected from 42,438 tested newborns in PR (2016 cohort) was tested to detect early stage I tumor among educated families without periodical exams. Estimation of R337H frequencies and ACT incidence in Santa Catarina state (SC) used data from 50,115 tested newborns without surveillance, ACT cases from a SC hospital, and a public cancer registry. R337H carrier frequencies in the population were 0.245% (SC) and 0.306% (PR), and 87% and 95% in ACTs, respectively. The ACT incidence was calculated as ~6.4/million children younger than 10 years per year in PR (95% CI: 5.28; 7.65) and 4.15/million in SC (CI 95%: 2.95; 5.67). The ACT penetrance in PR for probands followed from birth to 12 years was 3.9%. R337H carriers living in an agricultural subregion (C1) had a lower risk of developing pediatric ACT than those living in industrial and large urban subregion (relative risk = 2.4). One small ACT (21g) without recurrence (1/112) was detected by the parents in the 2016 cohort. ACT incidence follows R337H frequency in each population, but remarkably environmental factors modify these rates.

8.
Cancers (Basel) ; 11(11)2019 Nov 05.
Article in English | MEDLINE | ID: mdl-31694270

ABSTRACT

Adrenocortical carcinoma (ACC) is a rare disease among children. Our goal was to identify prognostic biomarkers in 48 primary ACCs from children (2.83 ± 2.3 y; mean age ± SD) by evaluating the tumor stage and outcome for an age of diagnosis before or after 3 years, and association with ACC cluster of differentiation 8 positive (CD8+) cytotoxic T lymphocytes (CD8+-CTL) and Ki-67 immunohistochemical expression (IHC). Programmed death 1(PD-1)/Programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) in ACC was analyzed in a second, partially overlapping cohort (N = 19) with a similar mean age. All patients and control children were carriers of the germline TP53 R337H mutation. Survival without recurrence for less than 3 years and death unrelated to disease were excluded. Higher counts of CD8+-CTL were associated with patients diagnosed with ACC at a younger age and stage I, whereas a higher percentage of the Ki-67 labeling index (LI) and Weiss scores did not differentiate disease free survival (DFS) in children younger than 3 years old. No PD-1 staining was observed, whereas weakly PD-L1-positive immune cells were found in 4/19 (21%) of the ACC samples studied. A high CD8+-CTL count in ACC of surviving children is compelling evidence of an immune response against the disease. A better understanding of the options for enhancement of targets for CD8+ T cell recognition may provide insights for future pre-clinical studies.

9.
Sci Total Environ ; 650(Pt 1): 1278-1291, 2019 Feb 10.
Article in English | MEDLINE | ID: mdl-30308815

ABSTRACT

The incidence of variable congenital malformation (CM) among 399 municipalities in the state of Paraná, southern Brazil, suggests the etiological role of environmental factors. This study examined a) environmental concentrations of chlorine anions (Cl-) associated with organochlorines (OCs) and b) associations between these chemicals and agricultural output with CMs using a geographical information system. In one of the three years during the sampling period (2008, 2009 or 2010) Cl-, dichlorodiphenyltrichloroethane (p,p'-DDT), dichlorodiphenyldichloroethylene (p,p'-DDE), dichlorodiphenyldichloroethane (p,p'-DDD), and endosulfan levels were measured in 465 (465/736, 63%) catchment basins. Agricultural outputs for crops during 2006-2010 were also evaluated (t/km2). Further, CM kernel density for the 399 municipalities in Paraná during 2007-2014 was investigated. Cl- levels increased significantly in one of the three years (2008, 2009 or 2010) in western catchment basins, compared to 1996 (p < 0.0001). The municipalities were divided according to the obtained Cl- levels, where sub-region C2 (central-southern) < 1.8 mg/L ≤ sub-regions C1 (northern-western) and C3 (eastern-southern). We identified 8756 cases of CMs among 1,221,287 newborns (NB) in all sub-regions. C1 had higher DDT-DDE-DDD (p,p'-DDT + p,p'-DDE + p,p'-DDD) concentrations, agricultural output, and CM kernel density. C2 and C3 had minor agricultural outputs (per square kilometer) and CM densities. A 2.96 mg/L increase in Cl- between sub-regions C1 and C2 was co-localized with a 45% increase in CM density (spatial relative risk = 1.45, CI 95%: 1.36-1.55). C1 had the highest log likelihood ratios (p = 0.001) identified via SaTScan clustering analyses. Organochlorines and other toxic chlorinated chemicals may contribute to CMs in humans, and these chemicals are ultimately transformed and release Cl- in rivers. Higher Cl- levels were correlated significantly with higher agricultural productivity, DDT-DDE-DDD levels, and CMs in some parts of the northern and western sub-regions (C1).

10.
Cancer Epidemiol ; 39(2): 166-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25736369

ABSTRACT

The tumor suppressor gene TP53 is the most frequently mutated gene in human cancer, and the germline TP53 R337H mutation is the most common mutation reported to date. However, this mutation is associated with a lower cumulative lifetime cancer risk than other mutations in the p53 DNA-binding domain. A detailed statistical analysis of 171,500 DNA tests in Brazilian neonates found that 0.27% of the general population is positive for this mutation, and some of the estimated 200,000 Brazilian R337H carriers in southern and southeastern Brazil have already developed cancer. The present study was designed to estimate R337H prevalence in neighboring Paraguay. To address this question, 10,000 dried blood samples stored in Guthrie cards since 2008 were randomly selected from the Paraguayan municipalities located at the border with Brazil. These samples were tested for R337H mutation using the PCR-restriction fragment length polymorphism assay. This germline mutation was detected in five samples (5/10,000), indicating that the total number of R337H carriers in Paraguay may be as high as 3500. Previous studies have shown that other countries (i.e., Portugal, Spain, and Germany) presented one family with this mutation, leading us to conclude that, besides Brazil and Paraguay, other countries may have multiple families carrying this mutation, which is an inherited syndrome that is difficult to control.


Subject(s)
Germ-Line Mutation/genetics , Neoplasms/genetics , Tumor Suppressor Protein p53/genetics , Genetic Predisposition to Disease , Humans , Paraguay , Prevalence
11.
J Clin Oncol ; 31(20): 2619-26, 2013 Jul 10.
Article in English | MEDLINE | ID: mdl-23733769

ABSTRACT

PURPOSE: The incidence of pediatric adrenocortical tumors (ACTs) is remarkably high in southern Brazil, where more than 90% of patients carry the germline TP53 mutation R337H. We assessed the impact of early detection of this mutation and of surveillance of carriers. PATIENTS AND METHODS: Free newborn screening was offered at all hospitals in the state of Paraná. Parents of positive newborns were tested, and relatives in the carrier line were offered screening. Positive newborns and their relatives age < 15 years were offered surveillance (periodic clinical, laboratory, and ultrasound evaluations). ACTs detected by imaging were surgically resected. RESULTS: Of 180,000 newborns offered screening, 171,649 were screened, and 461 (0.27%) were carriers. As of April 2012, ACTs had been diagnosed in 11 of these carriers but in only two neonatally screened noncarriers (P < .001); six patient cases were identified among 228 carrier relatives age < 15 years (total, 19 ACTs). Surveillance participants included 347 (49.6%) of 699 carriers. Tumors were smaller in surveillance participants (P < .001) and more advanced in nonparticipants (four with stage III disease; two deaths). Neonatally screened carriers also had neuroblastoma (n = 1), glioblastoma multiforme (n = 1), choroid plexus carcinoma (n = 2), and Burkitt lymphoma (n = 1). Cancer histories and pedigrees were obtained for 353 families that included 1,704 identified carriers. ACTs were the most frequent cancer among carrier children (n = 48). CONCLUSION: These findings establish the prevalence of the TP53 R337H mutation in Paraná state and the penetrance of ACTs among carriers. Importantly, screening and surveillance of heterozygous carriers are effective in detecting ACTs when readily curable.


Subject(s)
Adrenal Cortex Neoplasms/epidemiology , Adrenal Cortex Neoplasms/genetics , Genetic Predisposition to Disease/epidemiology , Genetic Testing/methods , Germ-Line Mutation , Tumor Suppressor Protein p53/genetics , Adrenal Cortex Neoplasms/diagnosis , Brazil/epidemiology , Child , Child, Preschool , Early Detection of Cancer/methods , Female , Gene Expression Regulation , Heterozygote , Humans , Incidence , Infant, Newborn , Male , Neonatal Screening/methods , Pedigree , Risk Assessment , Sex Distribution
12.
PLoS One ; 7(12): e50242, 2012.
Article in English | MEDLINE | ID: mdl-23284635

ABSTRACT

BACKGROUND: The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood. METHODS: The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels. RESULTS: Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz. CONCLUSIONS: Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.


Subject(s)
Androgens/pharmacology , Environmental Exposure , Voice/drug effects , Adolescent , Adrenal Cortex Neoplasms/drug therapy , Adrenal Cortex Neoplasms/physiopathology , Adult , Androgens/therapeutic use , Dose-Response Relationship, Drug , Female , Humans , Time Factors , Voice/physiology , Young Adult
13.
Mol Cell Endocrinol ; 351(1): 44-51, 2012 Mar 31.
Article in English | MEDLINE | ID: mdl-22056871

ABSTRACT

The high frequency of TP53 R337H carriers in southern Brazil is responsible for the highest known incidence of childhood adrenocortical tumor (ACT). Our aims were to examine other contributing mutations, age-related risk factors, epidemiological differences in ACT and to shed light on a method for increasing the survival rate of children. The fetal zone of the adrenal cortex is believed to be one of the tissues most susceptible to adenoma or carcinoma formation due to loss of p53 function. The founder germline R337H mutation is found in 95% of ACTs of young children, a much greater proportion than in adults. Despite intense educational campaigns about the high incidence of ACT in Paraná State, advanced cases remain common. Four advanced ACT cases (4/5) were admitted to a single institution in the first 6months of 2011 in Paraná State, none of the families knew about ACT, and 2 reported no familial cancer syndrome. Curative resection is possible when a small ACT is detected early.


Subject(s)
Adrenal Cortex Neoplasms/epidemiology , Adrenal Cortex Neoplasms/genetics , Mutation, Missense , Tumor Suppressor Protein p53/genetics , Adolescent , Adult , Age Factors , Brazil/epidemiology , Child , Child, Preschool , Female , Humans , Incidence , Male , Molecular Epidemiology
14.
J Pediatr Hematol Oncol ; 33(4): e149-53, 2011 May.
Article in English | MEDLINE | ID: mdl-21516013

ABSTRACT

The germline R337H mutation in the TP53 gene is considered to be responsible for the increased incidence of adrenocortical tumors (ACTs) in children from Brazil. High level production of hormones in ACTs (>95%) cause virilization alone (60%), Cushing syndrome (<5%), the mixed type (30%), or other rarer manifestations. ACT probably develops owing to events occurring during the final stages of intrauterine life based on the very common early onset of signs and symptoms shortly after birth. In this study, we determined by immunohistochemistry and enzyme assays whether placental alkaline phosphatase (PLAP) is expressed in pediatric ACTs. Immunohistochemical analysis revealed positive p53 expression in 88% of the tested ACTs (29 of 33). PLAP was detected at a slightly lower frequency based on immunohistochemical (17 of 33, 51%) and enzyme activity analyses (9 of 16, 56%). In conclusion, probably at a certain time point during adrenocortical development (end of gestation to early postnatal period), some fetal zone cells survive owing to defective apoptosis and develop into childhood ACT, maintaining some characteristics of the embryonal period, such as PLAP expression. Further studies of PLAP should investigate the functional role, if any, of PLAP in such tumors.


Subject(s)
Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/pathology , Adrenal Cortex/embryology , Adrenal Cortex/metabolism , Alkaline Phosphatase/metabolism , Isoenzymes/metabolism , Adrenal Cortex Neoplasms/genetics , Apoptosis/physiology , Child , Female , GPI-Linked Proteins/metabolism , Germ-Line Mutation , Humans , Immunohistochemistry , Male , Tumor Suppressor Protein p53/genetics
15.
PLoS One ; 6(3): e18015, 2011 Mar 22.
Article in English | MEDLINE | ID: mdl-21445348

ABSTRACT

BACKGROUND: Choroid plexus carcinomas (CPC) are rare tumors predominantly found in children. Given the high frequency of the germline R337H mutation in the TP53 gene in southern Brazil, we have evaluated the frequency of the R337H mutation in families with CPC in children. METHODOLOGY/PRINCIPAL FINDINGS: The present series included 29 patients that were admitted to the same institution from 1992 to 2010, including 22 children with CPC (0.08-13.6 years of age at diagnosis) and 7 children with papilloma of the choroid plexus (Pp; 0.5-9.8 years of age). Surgical resection was possible in 28 children. Blood and/or tumor DNA was extracted and analyzed using PCR-RFLP and results were confirmed by sequencing 240 bp of the TP53 exon 10. The patients, all parents, and some relatives submitted samples for blood DNA analysis. In addition, we have also examined the presence of the mutation in DNA from paraffin-embedded tumor samples to evaluate loss of heterozygosity. We found 63.3% (14/22) of the CPC patients positive for the germline R337H mutation; CPC samples were either heterozygous (n = 7), lost only the wild-type (n = 4), or only the R337H copy (n = 2). One CPC sample was not available. All Pp cases (7/7, 100%) were negative for R337H. Cure (>5 years survival free of disease) was observed in 18.1% of the CPC cases with the R337H mutation (2/11), 71.4% of the Pp (5/7), and 25% of CPC cases negative for the R337H mutation (2/8). Family history of cancer (with 2 or more cancer cases) was exclusively identified on the parental side segregating the R337H mutation, and 50% (7/14) of them were compatible with Li-Fraumeni-like syndrome. SIGNIFICANCE: Our results show for the first time that the R337H TP53 mutation is responsible for 63% of the CPC cases in children, suggesting a higher incidence of CPC in southern Brazil.


Subject(s)
Choroid Plexus Neoplasms/genetics , Germ-Line Mutation , Tumor Suppressor Protein p53/genetics , Base Sequence , Brazil/epidemiology , DNA Primers , Heterozygote , Humans , Incidence , Polymerase Chain Reaction
16.
Int J Oncol ; 36(4): 983-90, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20198344

ABSTRACT

The Li-Fraumeni syndrome (LFS) is a rare autosomal dominant hereditary cancer syndrome, characterized by a wide spectrum of neoplasms, occurring in children and young adults. The identification of germline TP53 mutations in LFS has given rise to a number of in vitro studies using cultures of cancer cells and non-tumoral fibroblasts presenting germline TP53 mutations. In the present study, we performed a detailed documentation of the pedigree of an LFS family with a comprehensive analysis of genotype-phenotype correlations. We sequenced the TP53 gene and verified that the proband carries a germline nonsense mutation in codon 146 in one allele, the TP53Arg72Pro polymorphism in the second, and other intronic polymorphisms in the TP53 gene. In order to investigate the disruption of the p53 function in a patient presenting this mutation and the TP53Arg72Pro polymorphism who had so far suffered five malignant tumors and a benign meningioma, we tested her fibroblasts in response to DNA damage by evaluating the proliferation rate, apoptosis, and disruption of the TP53 pathway. The proband's heterozygous fibroblasts were not as efficient as control fibroblasts or those of her mother, who carried only the TP53Arg72Pro polymorphism, in causing cell arrest and cell death after DNA damage, which was correlated with diminished TP21 protein levels.


Subject(s)
Codon, Nonsense , DNA Damage , Fibroblasts/metabolism , Germ-Line Mutation , Li-Fraumeni Syndrome/genetics , Tumor Suppressor Protein p53/genetics , Adult , Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis , Cell Cycle , Cell Proliferation , Cells, Cultured , Codon, Terminator , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Etoposide/pharmacology , Female , Fibroblasts/drug effects , Fibroblasts/pathology , Fibroblasts/radiation effects , Genotype , Heterozygote , Humans , Li-Fraumeni Syndrome/metabolism , Li-Fraumeni Syndrome/pathology , Male , Middle Aged , Pedigree , Phenotype , Polymorphism, Genetic , Tumor Suppressor Protein p53/metabolism
17.
Cancer Genet Cytogenet ; 186(1): 19-24, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18786438

ABSTRACT

A germline TP53 R337H mutation is present in childhood adrenocortical tumors (ACT) from southern Brazil. Other genetic alterations are also frequently found in these tumors. This study was designed to assess whether alterations of the 11p15 region exist in childhood ACT, accounting for IGF2 overexpression in these tumors, and how they are related to clinical outcome. Tumor DNA of 12 children with ACT (4 adenomas and 8 carcinomas) and from the blood of their parents was analyzed. All patients showed 11p15 loss of heterozygosity (LOH) in the tumor. In contrast to the single case of paternal LOH, IGF2 was overexpressed in tumors with maternal allele loss. Our data show that 11p15 LOH is a widespread finding in childhood ACT not related with malignancy, contrary to adult ACT. Alterations in the expression of other genes in the same region (e.g., CDKN1C) may contribute to ACT tumorigenesis.


Subject(s)
Adenoma/genetics , Adrenal Cortex Neoplasms/genetics , Amino Acid Substitution , Carcinoma/genetics , Chromosomes, Human, Pair 11/genetics , Genes, p53/genetics , Insulin-Like Growth Factor II/genetics , Loss of Heterozygosity , Mutation, Missense , Neoplasm Proteins/genetics , Neoplastic Syndromes, Hereditary/genetics , Point Mutation , Adenoma/epidemiology , Adenoma/mortality , Adolescent , Adrenal Cortex Neoplasms/epidemiology , Adrenal Cortex Neoplasms/mortality , Age Factors , Brazil/epidemiology , Carcinoma/epidemiology , Carcinoma/mortality , Child , Child, Preschool , Chromosomes, Human, Pair 11/ultrastructure , DNA Methylation , Gene Expression Regulation, Neoplastic , Genomic Imprinting , Germ-Line Mutation , Humans , Infant , Insulin-Like Growth Factor II/biosynthesis , Neoplasm Proteins/biosynthesis , Neoplastic Syndromes, Hereditary/epidemiology , Neoplastic Syndromes, Hereditary/mortality , Treatment Outcome
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