Colorectal cancer (CRC) is a leading global cause of illness and death. There is a need for identification of better prognostic markers beyond traditional clinical variables like grade and stage. Previous research revealed that abnormal expression of cytokeratin 7 (CK7) and loss of the intestinal-specific Special AT-rich sequence-binding protein 2 (SATB2) are linked to poor CRC prognosis. This study aimed to explore these markers' prognostic significance alongside two extraintestinal mucins (MUC5AC, MUC6), claudin 18, and MUC4 in 285 CRC cases using immunohistochemistry on tissue microarrays (TMAs). CK7 expression and SATB2-loss were associated with MUC5AC, MUC6, and claudin 18 positivity. These findings suggest a distinct "non-intestinal" immunohistochemical profile in CRC, often right-sided, SATB2-low, with atypical expression of CK7 and non-colorectal mucins (MUC5AC, MUC6). Strong MUC4 expression negatively impacted cancer-specific survival (hazard ratio = 2.7, p = 0.044). Genetic analysis via next-generation sequencing (NGS) in CK7 + CRCs and those with high MUC4 expression revealed prevalent mutations in TP53, APC, BRAF, KRAS, PIK3CA, FBXW7, and SMAD4, consistent with known CRC mutation patterns. NGS also identified druggable variants in BRAF, PIK3CA, and KRAS. CK7 + tumors showed intriguingly common (31.6%) BRAF V600E mutations corelating with poor prognosis, compared to the frequency described in the literature and databases. Further research on larger cohorts with a non-colorectal immunophenotype and high MUC4 expression is needed.

• Klíčová slova
• Claudin 18, Colorectal carcinoma, Cytokeratin 7, Mucin, NGS, SATB2,
• MeSH
• dospělí MeSH
• fenotyp MeSH
• fosfatidylinositol-3-kinasy třídy I genetika   metabolismus   MeSH
• imunohistochemie * MeSH
• keratin-7 metabolismus   genetika   MeSH
• kolorektální nádory * genetika   patologie   metabolismus   mortalita   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mucin 4 genetika   metabolismus   MeSH
• mucin 5AC genetika   metabolismus   MeSH
• mucin 6 genetika   metabolismus   MeSH
• mutace MeSH
• nádorové biomarkery * genetika   metabolismus   MeSH
• prognóza MeSH
• protoonkogenní proteiny B-Raf genetika   MeSH
• protoonkogenní proteiny p21(ras) genetika   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• transkripční faktory MeSH
• vazebné proteiny DNA v oblastech připojení k matrix * genetika   metabolismus   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• BRAF protein, human MeSH Prohlížeč
• fosfatidylinositol-3-kinasy třídy I MeSH
• keratin-7 MeSH
• KRAS protein, human MeSH Prohlížeč
• MUC4 protein, human MeSH Prohlížeč
• MUC5AC protein, human MeSH Prohlížeč
• MUC6 protein, human MeSH Prohlížeč
• mucin 4 MeSH
• mucin 5AC MeSH
• mucin 6 MeSH
• nádorové biomarkery * MeSH
• PIK3CA protein, human MeSH Prohlížeč
• protoonkogenní proteiny B-Raf MeSH
• protoonkogenní proteiny p21(ras) MeSH
• SATB2 protein, human MeSH Prohlížeč
• transkripční faktory MeSH
• vazebné proteiny DNA v oblastech připojení k matrix * MeSH