RESUMO
OBJECTIVE: FHIT gene encodes human diadenosine triphosphate hydrolase involved in the regulation of cell cycle and nucleotide metabolism and is a candidate tumor suppressor gene. AIM: To investigate expression of FHIT gene at the mRNA and protein levels in sporadic inflammatory bowel disease (IBD). MATERIALS AND METHODS: FHIT mRNA was quantified by the validated real-time PCR (QPCR) and FHIT protein was detected by immunohistochemistry (IHC) in mucosal biopsies of 139 ulcerative colitis (UC), 19 Crohn's disease (CD) and 37 control patients. RESULTS: Significant FHIT gene overexpression was found in 78% of active UC but not in CD. IHC showed comparable results to QPCR. CONCLUSION: The local up-regulation of FHIT gene and protein expression in active UC may represent an adequate response against inflammatory challenge of epithelial cell homeostasis and protect against DNA damage and cell cycle disturbances.
Assuntos
Hidrolases Anidrido Ácido/biossíntese , Doenças Inflamatórias Intestinais/metabolismo , Proteínas de Neoplasias/biossíntese , Hidrolases Anidrido Ácido/genética , Adolescente , Adulto , Idoso , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/genética , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Primers do DNA , Feminino , Humanos , Imuno-Histoquímica , Doenças Inflamatórias Intestinais/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Polônia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto JovemRESUMO
OBJECTIVE: FHIT gene, mapped at FRA3B site, encodes human diadenosine triphosphate hydrolase involved in the regulation of cell cycle and nucleotide metabolism. Decreased FHIT gene expression was previously observed in various types of human cancer, however, quantification of FHIT mRNA was seldom performed. AIM: To investigate loss of heterozygosity (LOH) at FRA3B, expression of FHIT gene at the mRNA and protein levels in sporadic colorectal carcinoma (CRC) and benign colon adenoma. MATERIALS AND METHODS: FHIT mRNA was quantified by the validated realtime PCR (QPCR) in tumor samples of 84 CRC patients and mucosal biopsies of 15 adenomas, in comparison to 37 control patients, whereas subgroup of 57 CRC, 10 adenoma and 10 control cases were selected for immunohistochemical (IHC) detection of the native FHIT protein and LOH determination at FRA3B. RESULTS: Higher level of FHIT mRNA was found in 86% of CRC (P<0.001) and 60% of adenomas (P=0.016). IHC showed comparable results to QPCR (P=0.003), revealing the strongest presence of FHIT protein in Dukes' C/D stages (P<0.001) and N1/N2 lymph nodes metastasis in CRC (P=0.04). FHIT gene expression and Dukes' and G staging were positively correlated in CRC as analyzed by QPCR and IHC. Deletion analysis of the fragile FRA3B site revealed the highest LOH frequency at D3S1234 in 32.5% of CRC informative cases, however, LOH did not correspond to QPCR, IHC or clinical-pathological variables. CONCLUSION: Our data suggest that reduction or absence of the FHIT gene expression is not a prerequisite for colorectal cancer development and progression.
Assuntos
Hidrolases Anidrido Ácido/biossíntese , Adenoma/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Neoplasias/biossíntese , Hidrolases Anidrido Ácido/genética , Adenoma/genética , Adenoma/patologia , Adulto , Idoso , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Primers do DNA , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Polônia , Estudos Prospectivos , RNA/biossíntese , RNA/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
OBJECTIVE: Although there is a convincing evidence supporting an important role for microorganisms in the pathogenesis of Inflammatory Bowel Disease (IBD) which comprises ulcerative colitis (UC) and Crohn's disease (CD), the specific mechanisms involved remain unclear. Toll-like receptors (TLR) recognize various molecules of microbiota including flagellin, the principal protein of motile comensal and pathogenic bacteria implicated in the pathogenesis of IBD. AIM: To investigate the expression of the TLR-5 receptors at the mRNA and protein levels in the mucosa of UC patients. MATERIALS AND METHODS: TLR-5 mRNA was quantified by the validated real-time PCR (QPCR) in mucosal biopsies of 99 UC patients and 34 control patients and TLR-5 protein was detected by immunohistochemistry (IHC) in 57 UC and 10 control patients. RESULTS: Significantly decreased TLR-5 gene expression at mRNA and protein level was found in the mucosa of patients with moderate and severe disease activity as compared to patients with low UC activity and control. TLR-5 immunoreactivity was found in the mucosa of UC patients and normal controls in the cytoplasm of enterocytes and at their basolateral domain. However, the intensity of the IHC reaction in specimens from UC patients was substantially lower than in control samples. CONCLUSION: The decreased expression of TLR-5 gene and protein in the mucosa of UC patients suggests that down-regulation of TLR-5 is probably caused by the increased number of ligand molecules in the proximity of epithelial cells in the inflamed tissue.