Germline TP53 mutations predispose individuals to multiple cancers and are associated with Li-Fraumeni/Li-Fraumeni-Like Syndromes (LFS/LFL). The founder mutation TP53 p.R337H is detected in 0.3% of the general population in southern Brazil. This mutation is associated with an increased risk of childhood adrenal cortical carcinoma (ACC) but is also common in Brazilian LFS/LFL families. Breast Cancer (BC) is one of the most common cancers diagnosed in TP53 mutation carriers. We have assessed the prevalence of p.R337H in two groups: (1) 59 BC affected women with a familial history (FH) suggestive of hereditary cancer syndrome but no LFS/LFL features; (2) 815 BC affected women unselected for cancer FH, diagnosed with BC at or before age 45 or at age 55 or older. Among group 1 and group 2 patients, 2/59 (3.4%, CI95%: 0.4%–11.7%) and 70/815 (8.6%, CI95%: 6.8%–10.7%), respectively, were p.R337H carriers in the germline. The prevalence of p.R337H was higher in women diagnosed with BC at or before age 45 (12.1%, CI95%: 9.1%–15.8%) than at age 55 or older (5.1%, CI95%: 3.2%–7.7%), p<0.001). The Brazilian founder p.R337H haplotype was detected in all carriers analysed. These results suggest that inheritance of p.R337H may significantly contribute to the high incidence of BC in Brazil, in addition to its recently demonstrated impact on the risk of childhood ACC.
Objective: Neurotrophin and neuropeptide pathways are emerging targets in cancer. Here we show that brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, are present in colorectal cancer and that BDNF levels are increased in tumors compared to nontumor tissue. In addition, we investigate the role of BDNF in influencing the response of colorectal cancer cells to inhibition of gastrin-releasing peptide receptors (GRPR). Methods: Fresh-frozen sporadic colorectal adenocarcinoma specimens and adjacent nonneoplastic tissue from 30 patients, as well as paraffin-embedded colorectal cancer samples from 21 patients, were used in this study. Cell proliferation and mRNA and protein levels were examined in HT-29 or SW620 cells treated with a GRPR antagonist, human recombinant BDNF (hrBDNF), a Trk antagonist K252a, or cetuximab. Results: Expression of BDNF and TrkB was detected in tumor samples and cell lines. BDNF levels were higher in tumor samples compared to nonneoplastic tissue. BDNF expression and secretion were increased by GRPR blockade in HT-29 cells through a mechanism dependent on epidermal growth factor receptors. Treatment with hrBDNF prevented the effect of GRPR blockade on cell proliferation, whereas a Trk inhibitor reduced proliferation. Conclusions: BDNF and TrkB are present in colorectal cancer and might contribute to resistance to GRPR antagonists.
-The objective of this work was to characterize mandarin (Citrus spp.) germplasm from Southern Brazil by morphological and molecular analyses. Thirty seven cultivars from 34 distinct mandarin varieties were evaluated by morphological and agronomic traits of leaves, flowers and fruits, and by microsatellite markers. The morphological and agronomic characteristics suggested that almost all varieties can be produced for commercial use, and some, as the Satsuma variety, are recommended for breeding programs. Pooled DNA samples from 1-5 plants belonging to each cultivar were tested. Eight of the nine primers detected polymorphisms. Specific markers were found for some accessions. The dendrogram constructed with the morphological results divided the 37 cultivars into four groups, while that obtained with the microsatellites clustered 35 of the 37 cultivars into three groups only. Generally, intervarietal differences are not high, and this lack of agreement in the two multifactorial analyses indicates that diverse evolutionary factors are acting at these two levels of investigation.Index terms: citrus, genetic variation, microsatellites, breeding methods. Caracterização do germoplasma de tangerineiras do Sul do Brasil mediante análises morfológicas e molecularesResumo -O objetivo deste trabalho foi caracterizar o germoplasma de tangerineiras (Citrus spp.) por meio de análises morfológicas e moleculares. Trinta e sete cultivares, pertencentes a 34 variedades distintas de tangerineiras, foram avaliadas pelas características morfológicas e agronômicas de folhas, flores e frutos, bem como por análises de microssatélites. As características morfológicas e agronômicas sugerem que praticamente todas as variedades podem ser usadas comercialmente e algumas delas, como a variedade Satsuma, são recomendadas para uso em cruzamentos dirigidos. O DNA foi obtido de amostras extraídas de uma a cinco plantas de cada cultivar. Oito de nove primers detectaram polimorfismos. Foram encontrados marcadores específicos para alguns acessos. O dendrograma construído com os resultados morfológicos dividiu as 37 cultivares em quatro grupos, enquanto o obtido com os microssatélites agrupou 35 das 37 cultivares em três grupos. As diferenças intervarietais não são grandes, e esta falta de concordância nas duas análises multivariadas indica que fatores evolutivos diversos estão agindo nesses dois níveis de investigação.Termos para indexação: citros, variação genética, microsatélites, método de melhoramento.
About 5-10% of breast and ovarian carcinomas are hereditary and most of these result from germline mutations in the BRCA1 and BRCA2 genes. In women of Ashkenazi Jewish ascendance, up to 30% of breast and ovarian carcinomas may be attributable to mutations in these genes, where 3 founder mutations, c.68_69del (185delAG) and c.5266dup (5382insC) in BRCA1 and c.5946del (6174delT) in BRCA2, are commonly encountered. It has been suggested by some authors that screening for founder mutations should be undertaken in all Brazilian women with breast cancer. Thus, the goal of this study was to determine the prevalence of three founder mutations, commonly identified in Ashkenazi individuals in a sample of non-Ashkenazi cancer-affected Brazilian women with clearly defined risk factors for hereditary breast and ovarian cancer (HBOC) syndrome. Among 137 unrelated Brazilian women from HBOC families, the BRCA1c.5266dup mutation was identified in seven individuals (5%). This prevalence is similar to that encountered in non-Ashkenazi HBOC families in other populations. However, among patients with bilateral breast cancer, the frequency of c.5266dup was significantly higher when compared to patients with unilateral breast tumors (12.1% vs 1.2%, p = 0.023). The BRCA1 c.68_69del and BRCA2 c.5946del mutations did not occur in this sample. We conclude that screening non-Ashkenazi breast cancer-affected women from the ethnically heterogeneous Brazilian populations for the BRCA1 c.68_69del and BRCA2 c.5946del is not justified, and that screening for BRCA1c.5266dup should be considered in high risk patients, given its prevalence as a single mutation. In high-risk patients, a negative screening result should always be followed by comprehensive BRCA gene testing. The finding of a significantly higher frequency of BRCA1 c.5266dup in women with bilateral breast cancer, as well as existence of other as yet unidentified founder mutations in this population, should be further assessed in a larger well characterized high-risk cohort.
X-linked adrenoleukodystrophy (X-ALD) is an inherited disease characterized by progressive inflammatory demyelization in the brain, adrenal insufficiency, and an abnormal accumulation of very long chain fatty acids (VLCFA) in tissue and body fluids. Considering that inflammation might be involved in pathophysiology of X-ALD, we aimed to investigate pro-and anti-inflammatory cytokines in plasma from three different male phenotypes (CCER, AMN, and asymptomatic individuals). Our results showed that asymptomatic patients presented increased levels of proinflammatory cytokines IL-1β, IL-2, IL-8, and TNF-α and the last one was also higher in AMN phenotype. Besides, asymptomatic patients presented higher levels of antiinflammatory cytokines IL-4 and IL-10. AMN patients presented higher levels of IL-2, IL-5, and IL-4. We might hypothesize that inflammation in X-ALD is related to plasmatic VLCFA concentration, since there were positive correlations between C26:0 plasmatic levels and pro-inflammatory cytokines in asymptomatic and AMN patients and negative correlation between anti-inflammatory cytokine and C24:0/ C22:0 ratio in AMN patients. The present work yields experimental evidence that there is an inflammatory imbalance associated Th1, (IL-2, IL-6, and IFN-γ), Th2 (IL-4 and IL-10), and macrophages response (TNF-α and IL-1β) in the periphery of asymptomatic and AMN patients, and there is correlation between VLCFA plasmatic levels and inflammatory mediators in X-ALD. Furthermore, we might also speculate that the increase of plasmatic cytokines in asymptomatic patients could be considered an early biomarker of brain damage and maybe also a predictor of disease progression.
Introduction Studies have shown that T2DM is an inflammatory disease. Thus, the present study was aimed at evaluating whether diacerein could improve the metabolic and inflammatory profile among patients with T2DM under long-term treatment with glucose-lowering agents. Methods This is a double-blind, parallel, placebo-controlled trial with 72 participants randomly assigned to diacerein 50 mg or placebo for 12 weeks. The primary endpoint was the between-group difference in change in HbA1c. Secondary endpoints included the proportion of patients achieving metabolic control [HbA1c ≤ 7.0% (53 mmol/mol)] and change in inflammatory mediators. Results Participants in the diacerein group had greater reductions in mean HbA1c level in comparison to placebo (−0.98; 95% CI: −2.02 to 0.05, P = 0.06), independently of confounding factors. The difference in HbA1c level was −1.3 (95% CI: −2.3 to −0.4) in favor of diacerein (P = 0.007) in those with <14 years of diabetes duration versus 0.05 (−0.7 to 0.8; P = 0.9) in those with longer duration. The diacerein group had a 50% increase in the number of participants at the lowest TNF-α level (≤1.46 pg/mL). Conclusions In patients with long-established T2DM under long-term treatment with glucose-lowering agents, diacerein improves metabolic control as measured by HbA1c level and has a favorable impact on inflammatory profile. Clinical Trial Registry This trial is registered with Brazilian Clinical Trials Registry (ReBEC) number RBR-29j956.
A few studies have reported phyllodes tumors (PT) of the breast with germline TP53 mutations. Given this potential association and the high frequency of the TP53 p.R337H in southern and southeastern Brazil, the aim of this study was to assess whether p.R337H occurs among women diagnosed with such rare tumors in this region. Benign, borderline, and malignant breast PT were retrieved from eight pathology laboratories, and DNA was extracted from tumor tissue to perform p.R337H analysis. Overall, 128 cases classified as benign, 7 as borderline, and 13 as malignant PT were included in the study. The TP53 p.R337H mutation was identified in tumor cells of eight (5.4 %) cases. Analysis of DNA from non-tumoral tissue was possible in two of these, and both were p.R337H carriers in the germline. In addition, haplotype analysis was done in these two p.R337H carriers showing the presence of the founder haplotype previously reported in Brazilian mutation-positive individuals. Mutation frequency was significantly higher among malignant (3 of 13; 23 %) compared to benign tumors (5 of 128; 3.4 %) (p = 0.004). Mean age at PT diagnosis was not significantly different between mutation carriers and non-carriers. However, when subgroups where analyzed, the difference in age at diagnosis of carriers versus non-carriers within the group of benign tumors reached borderline significance. Our findings reinforce previous evidence that TP53 mutations have an important role in the development of both benign and malignant PT of the breast.
Lynch syndrome (LS) is the most common hereditary colorectal cancer syndrome, caused by germline mutations in one of the major genes involved in mismatch repair (MMR): MLH1,MSH2,MSH6 and more rarely, PMS2. Recently, germline deletions in EPCAM have been also associated to the syndrome. Most of the pathogenic MMR mutations found in LS families occur in MLH1 or MSH2. Gene variants include missense, nonsense, frameshift mutations, large genomic rearrangements and splice‐site variants and most of the studies reporting the molecular characterization of LS families have been conducted outside South America. In this study, we analyzed 60 unrelated probands diagnosed with colorectal cancer and LS criteria. Testing for germline mutations and/or rearrangements in the most commonly affected MMR genes (MLH1, MSH2, EPCAM and MSH6) was done by Sanger sequencing and MLPA. Pathogenic or likely pathogenic variants were identified in MLH1 or MSH2 in 21 probands (35.0%). Of these, approximately one‐third were gene rearrangements. In addition, nine variants of uncertain significance (VUS) were identified in 10 (16.6%) of the sixty probands analyzed. Other four novel variants were identified, only in MLH1. Our results suggest that MSH6 pathogenic variants are not common among Brazilian LS probands diagnosed with CRC and that MMR gene rearrangements account for a significant proportion of the germline variants in this population underscoring the need to include rearrangement analysis in the molecular testing of Brazilian individuals with suspected Lynch syndrome.
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