Colorectal cancer (CRC) is the most common disease and cause of death globally. The aim of the study is investigation and detection of some bacterial interfering with CRC occurrence and progression. The study conducted between September 2022 till February 2023, a total of 50 specimens were collected from confirmed CRC patients. In addition, 50 stool specimens were collected from Healthy volunteers, considers as control group. Isolation and identification of bacteria in all collected specimens were done by using cultural and differential media (blood agar, macconkey agar and Pfizer agar), as well as the VITEK- 2 compact system. The bacterial species, in the specimens of control were ( Escherichia coli 50 (86.20%), Klebsiella Pneumonia 3(5.17%), Salmonella typhi 2(3.44%), Staphylococcus aureus 1(1.72%), Proteus mirabilis 1(1.72%) and Pseudomonas aeruginosa 1(1.72%), while in the specimens of CRC and polyp were (Escherichia coli 30(38.69%), Streptococcus uberis 6(7.79%), Enterobacter cloacae 4(5.19%), Proteus mirabilis 11(14.28), Streptococcus constellatus pharyneis 1(1.29%), Micrococcus luteus 1(1.29%), Staphlococcus pseudintermedius 1(1.29%), Streptococcus thoraltensis 1(1.29%), Citrobacter freundii 1(1.29%), Streptoccus mutans 1(1.29%), Enterococcus faecium 5(6.49%), Enterococcus faecalis 4(5.19%), Granulicatella elegans 1(1.29%), Enterococcus gallinarum 2(2.59%), Serratia marcescens 1(1.29%), Streptococcus sangunis 1(1.29%), Staphylococcus lentus 1(1.29%), Comamons testosteroni 1(1.29%), Morganella morganii 1(1.29%), Pseudomonas aeruginosa 1(1.29%), Klebsiella pneumonia 2(2.59%). The bacteria which has been shown to be associated and more abundance in the specimens of CRC tissues are Escherichia.coli 30(38.96%), Streptococcus uberis 6(7.79%), Enterobacter cloacae 4(5.19%), Enterococcus faecium 5(6.49%), Enterococcus faecalis 4(5.19%). Cell-line culture techniques for the five species showed a cellular viability, sequentially Streptocccus uberis (16.12%), Enterococcus faecium (16.39%), Entreococcus faecalis (9.48%), Enterobacter cloacae (15.11%) and Escherichia coli (17.61%). The results statistically studied by using SPSS, which showed excellent or (highly) significant (p-value is in the range of 0.001).
