RESUMO
BACKGROUND: Colorectal cancer is one of the most commonly diagnosed cancers around the world. One of the factors involved in the development of colorectal cancer is the changes in the normal flora of the intestine. OBJECTIVE: In this study, the mean copy number of Enterococcus faecalis in people with polyps and people with colorectal cancer has been evaluated in comparison with healthy controls. METHODS: In this study, 25 patients with colorectal cancer and 28 patients with intestinal polyps were selected and stool specimens were taken. In addition, 24 healthy individuals were selected as control group. Extraction of bacterial DNA from the stool sample were performed. The molecular methods of PCR for confirmation of standard strain and absolute Real Time PCR (qRT-PCR) method were used to evaluate the number of Enterococcus faecalis in the studied groups. RESULTS: The results of this study indicate that the mean copy number of Enterococcus faecalis in patients with colorectal cancer was 11.2x109 per gram of stool, and in patients with polyps was 9.4x108 per gram of stool. In healthy people, this number was 9x108 per gram of stool. There was a significant difference between the implicit copy numbers in the three groups. (P<0.05). CONCLUSION: Enterococcus faecalis in faecal flora of people with colorectal cancer was significantly higher than those with polyps and healthy people. This could potentially signify the ability of this bacterium to induce colorectal cancer. More studies are needed to prove this theory.
Assuntos
Pólipos do Colo/microbiologia , Neoplasias Colorretais/microbiologia , Enterococcus faecalis/isolamento & purificação , Fezes/microbiologia , Idoso , Estudos de Casos e Controles , DNA Bacteriano/análise , Enterococcus faecalis/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo RealRESUMO
ABSTRACT BACKGROUND: Colorectal cancer is one of the most commonly diagnosed cancers around the world. One of the factors involved in the development of colorectal cancer is the changes in the normal flora of the intestine. OBJECTIVE: In this study, the mean copy number of Enterococcus faecalis in people with polyps and people with colorectal cancer has been evaluated in comparison with healthy controls. METHODS: In this study, 25 patients with colorectal cancer and 28 patients with intestinal polyps were selected and stool specimens were taken. In addition, 24 healthy individuals were selected as control group. Extraction of bacterial DNA from the stool sample were performed. The molecular methods of PCR for confirmation of standard strain and absolute Real Time PCR (qRT-PCR) method were used to evaluate the number of Enterococcus faecalis in the studied groups. RESULTS: The results of this study indicate that the mean copy number of Enterococcus faecalis in patients with colorectal cancer was 11.2x109 per gram of stool, and in patients with polyps was 9.4x108 per gram of stool. In healthy people, this number was 9x108 per gram of stool. There was a significant difference between the implicit copy numbers in the three groups. (P<0.05). CONCLUSION: Enterococcus faecalis in faecal flora of people with colorectal cancer was significantly higher than those with polyps and healthy people. This could potentially signify the ability of this bacterium to induce colorectal cancer. More studies are needed to prove this theory.
RESUMO CONTEXTO: O câncer colorretal é um dos cânceres mais comumente diagnosticados em todo o mundo. Um dos fatores envolvidos no desenvolvimento do câncer colorretal é a mudança na flora normal do intestino. OBJETIVO: O número médio de cópias de Enterococcus faecalis em pessoas com pólipos e pessoas com câncer colorretal foram avaliados em comparação com controles saudáveis. MÉTODOS: Neste estudo, 25 pacientes com câncer colorretal e 28 pacientes com pólipos intestinais foram selecionados e amostras de fezes foram adquiridas. Além disso, 24 indivíduos saudáveis foram selecionados como grupo controle. A extração do DNA bacteriano da amostra coletada foi executada. Os métodos moleculares de PCR para confirmação da cepa padrão e o método absoluto de PCR em tempo real (qRT-PCR) foram utilizados para avaliar o número de Enterococcus faecalis nos grupos estudados. RESULTADOS: Os resultados deste estudo indicam que o número médio de cópias de Enterococcus faecalis em pacientes com câncer colorretal foi de 11,2x109 por grama de fezes, e em pacientes com pólipos foi de 9,4x108 por grama de fezes. Em pessoas saudáveis, este número foi de 9x108 por grama de fezes. Houve diferença significativa entre os números de cópia implícita nos três grupos. (P<0,05). CONCLUSÃO: Enterococcus faecalis na flora fecal de pessoas com câncer colorretal foi significativamente maior do que aqueles com pólipos e pessoas saudáveis. Isto poderia potencialmente significar a capacidade desta bactéria para induzir o câncer colorretal. Mais estudos são necessários para provar esta teoria.