Metabolic pathways in sporadic colorectal carcinogenesis: A new proposal.

Given the reports made about geographical differences in Colorectal Cancer (CRC) occurrence, suggesting a link between dietary habits, genes and cancer risk, we hypothesise that there are four fundamental metabolic pathways involved in diet-genes interactions, directly implicated in colorectal carcinogenesis: folate metabolism; lipid metabolism; oxidative stress response; and inflammatory response. Supporting this hypothesis are the evidence given by the significant associations between several diet-genes polymorphisms and CRC, namely: MTHFR, MTR, MTRR and TS (involved in folate metabolism); NPY, APOA1, APOB, APOC3, APOE, CETP, LPL and PON1 (involved in lipid metabolism); MNSOD, SOD3, CAT, GSTP1, GSTT1 and GSTM1 (involved in oxidative stress response); and IL-1, IL-6, TNF-α, and TGF-ß (involved in inflammatory response). We also highlight the association between some foods/nutrients/nutraceuticals that are important in CRC prevention or treatment and the four metabolic pathways proposed, and the recent results of genome-wide association studies, both assisting our hypothesis. Finally, we propose a new line of investigation with larger studies, using accurate dietary biomarkers and investigating the four metabolic pathways genes simultaneously. This line of investigation will be essential to understand the full complexity of the association between nature and nurture in CRC and perhaps in other types of cancers. Only with this in-depth knowledge will it be possible to make personalised nutrition recommendations for disease prevention and management.

Amplification of FGFR1 gene and expression of FGFR1 protein is found in different histological types of lung carcinoma.

Although lung cancer continues to be the leading cause of cancer-related death, accurate diagnosis followed by personalized treatment is expected to raise the 5-year survival rate. Targeted therapies are now in routine clinical use, in particular for lung adenocarcinoma (ADC). Fibroblast growth factor receptor 1 (FGFR1) has recently emerged as a molecular target, especially in squamous cell/epidermoid carcinoma (SQC) of the lung. This paper evaluates FGFR1 expression and gene copy number in adenocarcinomas, squamous cell carcinomas, pleomorphic carcinomas (PLEOMC) and adenosquamous carcinomas (ADSQC) of the lung and also explores the epithelial-mesenchymal transition (EMT) pathway. We studied 76 lung carcinomas: 34 ADC, 24 SQC, 10 PLEOMC and 8 ADSQC. FGFR1 expression was evaluated by immunohistochemistry and gene amplification by fluorescence in situ hybridization (FISH). Higher FGFR1 protein expression was observed in all tumour types compared to non-tumour tissue. FGFR1 expression was higher in ADC and PLEOMC than in SQC. We found a tendency to higher expression in ADC than in SQC and significantly higher expression in PLEOMC than in other histological subtypes. FISH-based amplification of FGFR1 was identified in 15 (20 %) lung carcinomas: 5 (15 %) ADC, 5 (21 %) SQC, 3 (30 %) PLEOMC and 2 (25 %) ADSQC. Amplification was more frequent in SQC without significant differences. FGFR1 protein is expressed in the majority of lung carcinomas, though it is higher in ADC and PLEOMC (the latter may reflect the importance of FGFR1 control of the EMT pathway). FGFR1 amplification was identified in all types of lung carcinoma. Although FGFR1 is most frequently amplified in SQC, other histological types merit assessment of FGFR1 amplification, in order to select patients that might benefit from targeted therapy.

Evaluation of HER2 by automated FISH and IHC in gastric carcinoma biopsies.

PURPOSE: The use of trastuzumab (Herceptin) to target HER2 has been applied in breast carcinoma and gastric carcinoma (GC). Previous studies have tested trastuzumab's effectiveness by assessing HER2 expression or HER2 amplification by means of immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH). In this work we aimed to evaluate automated FISH and IHC technologies for HER2 detection in GC biopsies to be used in routine pathology practice. METHODS: The study used an Oracle HER2 IHC System and an LSI HER2/CEP17 Dual Probe on an automated Bond system (Leica Microsystems). One hundred GC biopsies were evaluated including 44 intestinal type, 38 diffuse type and 18 indeterminate type according to Lauren's classification. RESULTS: The overall concordance rate between the automated FISH and IHC methods was 94% (κ = 0.87), as 6 samples were scored as equivocal (4 in IHC and 2 in FISH). Moreover, HER2 positivity was significantly different between the 3 types of GC (p<0.05), being more frequent in intestinal-type GC (23%) than in the other 2 histological types (5% and 0%). Finally, the HER2/CEP17 FISH ratio was significantly different (p<0.01) between disomic and polysomic samples, being higher in polysomic samples (mean 1.633 ± 0.509) than in disomic samples (mean 1.231 ± 0.675). CONCLUSIONS: Automated HER2 testing of GC biopsies using the Leica Bond system was useful and efficient. This method allowed us to improve normal routine procedures, minimizing time and costs as well as handling and observation errors.

Association Between IL-4 and IL-6 Expression Variants and Gastric Cancer Among Portuguese Population.

INTRODUCTION: Multiple studies have reported strong associations between Helicobacter pylori (Hp) inflammation and gastric cancer (GC) development. Altered expressions of pro/anti-inflammatory cytokines have a crucial role in Hp and GC proliferation. Although there are many studies related to cytokines polymorphisms involvement in GC risk, the role of Interleukin-4 (IL-4) and Interleukin-6 (IL-6) in gastric inflammation process is not yet clarified. AIM: This study aimed to investigate the impact of common IL-4 and IL-6 polymorphisms in GC development risk among Portuguese population. METHODS: A total of 100 GC biopsies (50 with intestinal type, IGC, 50 with diffuse type, DGC) and 50 chronic gastritis cases, used as control group, were included in this case-control study. IL-4 and IL-6 common polymorphisms were genotyped by PCR-SSP, using commercially available kits. RESULTS: IL-4 low producer genotypes, IL-4-590TT (OR = 6.7; 95% CI 1.4-32.4) and IL-4-1098GG (OR = 4.4; 95% CI 1.7-16.9) were found associated with IGC and DGC, respectively. We also verified that IL-4 TTT haplotype was linked with both IGC (OR = 5.8; 95% CI 2.3-14.4) and DGC (OR = 2.3; 95% CI 1.0-5.5) groups. Concerning IL-6 results, IL-6-174CG genotype showed a higher prevalence among IGC cases (OR = 7.3; 95% CI 2.7-20.3), and IL-6-174CC (OR = 3.8; 95% CI 1.7-8.7) showed upper prevalence within DGC subjects. Finally, IL-6-174/nt565CG haplotype showed a significant association with both IGC (OR = 7.3; 95% CI 2.7-20.3) and DGC (OR = 7.9; 95% CI 4.2-14.9). CONCLUSION: IL-6 and IL-4 expression variants seem to have an important role in GC risk mechanisms. This study provides preliminary evidence that IL-4 and IL-6 polymorphisms, although not directly linked to the disease, may be useful tools in the study of this multifactorial disease.

INTRODUÇÃO: Múltiplos estudos têm referenciado fortes associações entre infeção/inflamação por Helicobacter pylori (Hp) e o desenvolvimento do cancro gástrico (CG). A alteração na expressão das citocinas pro/anti-inflamatórias desempenha um papel crucial na proliferação da Hp e do CG. Apesar de existirem vários estudos relacionados com os polimorfismos das citocinas envolvidos na progressão do CG, o papel da Interleukin-4 (IL-4) e Interleukin-6 (IL-6) no mecanismo de inflamação gástrica ainda não está totalmente esclarecido. OBJETIVO: Este estudo teve como objetivo principal estudar o impacto dos polimorfismos comuns da IL-4 e IL-6 no risco de desenvolvimento do CG na população Portuguesa. MÉTODOS: Um total de 100 biópsias de CG (50 do tipo intestinal, CGI, 50 do tipo difuso, CGD) e 50 casos de gastrite crónica, utilizados como grupo controlo, foram incluídos neste estudo de caso-controlo. Os polimorfismos da IL-4 e da IL-6 foram genotipados por PCR-SSP, utilizando kits comerciais disponíveis. RESULTADOS: Os genótipos de baixa produção da IL-4, IL-4 -590TT (OR = 6,7; 95% CI 1,4 a 32,4) e IL-4 -1098GG (OR = 4,4; 95% CI 1,7 a 16,9) encontram-se associados com o CGI e com o CGD, respetivamente. Também verificámos que o haplótipo IL-4 TTT encontra-se relacionado com ambos os grupos de CGI (OR = 5,8; 95% CI 2,3 a 14,4) e CGD (OR = 2.3; 95% CI 1,0 a 5,5). Considerando os resultados da IL-6, o genótipo IL-6-174CG apresentou uma elevada prevalência entre os pacientes com CGI (OR = 7,3; 95% CI 2,7 a 20,3), e o IL-6 -174CC (OR = 3,8; 95% CI 1,7 a 8,7) apresentou maior prevalência no grupo de CGD. Finalmente, o haplótipo IL-6 -174/nt565CG apresentou uma associação significativa com ambos os grupos de CGI (OR = 7,3; 95% CI 2,7 a 20,3) e CGD (OR = 7,9; 95% CI 4,2 a 14,9). CONCLUSÃO: Os variantes de expressão da IL-6 e IL-4 parecem desempenhar um papel importante nos mecanismos de progressão do CG. Este estudo fornece evidências preliminares de que os polimorfismos da IL-4 e da IL-6, apesar de não estarem diretamente ligados a esta patologia, podem ser ferramentas úteis no estudo desta doença multifatorial.

[Gastric carcinoma and chronic gastritis: epigenetic regulation of CDH1 (E-Cadherin), CDKN2A (p16INK4A), PTGS2 (COX-2) and EGFR genes through methylation]. / Carcinoma gástrico e gastrite crónica: regulação epigenética por metilação dos genes CDH1 (Caderina-E), CDKN2A (p16INK4A), PTGS2 (COX2) e EGFR.

The genetic and epigenetic alterations are being studied as one of the causes of gastric cancer (GC) progression and development. DNA methylation is an epigenetic alteration which leads to suppressor gene silencing and proto-oncogene activation, playing an important role in carcinogenesis. The histological types of gastric carcinoma have different genetic paths and the knowledge of the molecular bases of tumoral progression leads to diagnostic accuracy and attempted therapy. CDH1 (E-cadherin) and CDKN2A (p16(INK4A)) genes are thought to be tumoral suppressor genes and PTGS2 (COX-2) and genes are involved in tumour regulation and growth. In one hand, gene silencing as an epigenetic phenomenon, and in the other hand, gene expression enhancement due to possible demethylation, simultaneously, can facilitate carcinogénesis and tumoral progression. Our aim was to relate CDH1, p16(INK4A), COX-2 and EGFR genes DNA methylation with the several histological types of gastric carcinoma and chronic gastritis. We studied 55 formalin fixed paraffin embedded gastric biopsies: 35 were GC specimens (12 diffuse type, 15 intestinal type and 8 indeterminate type, according to Laurén's classification) and 20 samples had chronic gastritis (CG). The DNA was treated with sodium bisulfite after extraction and then performed Methylation Specific PCR (MSP). Statistical analysis was based on chi-square test and Exact Fisher's test. CpG island methylation was detected in 94% of the GC samples for CDH1, 91% for COX-2, 80% for p16(INK4A) and no methylation was detected in EGFR gene (0%). In CG, CpG island methylation was found in 100% for CDH1 and COX-2 genes, 90% for p16(INK4A) and 20% for EGFR. These results reveal significant differences in EGFR gene methylation distinguishing GC from CG (p < 0, 01), suggesting that gene demethylation leads to malignant transformation and favours the use of tyrosine-kinase inhibitors in its treatment. Genes COX2 e p16INK4A lower methylation in intestinal and diffuse types of GC, favours their different role in respective histogenesis.

Why are human newborns so fat? Relationship between fatness and brain size at birth.

The plumpness of the human newborn has long been recognized as a trait in need of explanation among researchers. Using a linear regression analysis, we find that head circumference is significantly and positively associated with BMI at birth, after gestational age and birthlength were controlled for, in a sample of 1,069 healthy liveborn routinely delivered at the University Hospital of Coimbra (partial correlation r = 0.409, P < 0.0001). This significant association is consistent with the idea that newborn fatness is related to the higher need of lipids in newborn humans as an energetic and plastic substrate during its accelerated brain growth period. As birthweight and birth head size are associated with head size and cognitive abilities in childhood and adult life, it could be postulated that these cognitive abilities could have acted as selective pressure responsible for the newborn fatness increase in our lineage.