AUTHOR=Kamali Dolatabadi Razie , Fazeli Hossein , Emami Mohammad Hassan , Karbasizade Vajihe , Maghool Fatemeh , Fahim Alireza , Rahimi Hojatollah 

TITLE=Phenotypicand Genotypic Characterization of Clinical Isolates of Intracellular Adherent–Invasive Escherichia coli Among Different Stages, Family History, and Treated Colorectal Cancer Patients in Iran

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.938477

DOI=10.3389/fcimb.2022.938477

ISSN=2235-2988

ABSTRACT=<p>There is increasing evidence showing that microbial dysbiosis impacts the health and cancer risk of the host. An association between adherent–invasive <italic>Escherichia coli</italic> (AIEC) and colorectal cancer (CRC) has been revealed. Cyclomodulins (CMs) have been receiving increasing attention for carcinogenic changes. In this study, the incidence and features of intracellular AIEC and cyclomodulin-encoding genes were investigated and the phylogenetic grouping and genetic relatedness were evaluated. <italic>E. coli</italic> strains were isolated from the colorectal biopsies. Adhesion and invasion assays and intramacrophage cell survival test were performed to separate the AIEC isolates. Virulence genotyping for the genes <italic>htrA</italic>, <italic>dsbA</italic>, <italic>chuA</italic>, and <italic>lpfA</italic> and the cyclomodulin toxins was also conducted. In addition, phylogenetic grouping of the isolates was determined. Subsequently, repetitive element sequence-based PCR (rep-PCR) fingerprinting was performed. A total of 24 AIEC pathovars were isolated from 150 patients. The prevalence rates of <italic>htr</italic>, <italic>dsbA</italic>, and <italic>lpfA</italic> were 70.83% and that of <italic>chuA</italic> was 91.66%. The frequencies of the cyclomodulin toxins were as follows: <italic>cnf1</italic>, 29.2%; <italic>cnf2</italic>, 25%; colibactin, 29.2%; and <italic>cdt</italic>, 4.2%; <italic>cif</italic> was not found. Among the AIEC isolates, 4.2%, 4.2%, 54.2%, 29.2%, and 8.3% with phylotypes A or C, B1, B2, D, and E were identified, respectively. Left-sided colon carcinoma and adenocarcinoma T≥1 stage (CRC2) were colonized by B2 phylogroup AIEC-producing CMs more often than the samples from the other groups. Close genetic relatedness was observed in AIEC isolates with rep-PCR.</p>