Most of the organs of the digestive tract comprise secretory epithelia that require specialized molecular machines to achieve their functions. As such anterior gradient (AGR) proteins, which comprise AGR1, AGR2, and AGR3, belong to the protein disulfide isomerase family, and are involved in secretory and transmembrane protein biogenesis in the endoplasmic reticulum. They are generally expressed in epithelial cells with high levels in most of the digestive tract epithelia. To date, the vast majority of the reports concern AGR2, which has been shown to exhibit various subcellular localizations and exert pro-oncogenic functions. AGR2 overexpression has recently been associated with a poor prognosis in digestive cancers. AGR2 is also involved in epithelial homeostasis. Its deletion in mice results in severe diffuse gut inflammation, whereas in inflammatory bowel diseases, the secretion of AGR2 in the extracellular milieu participates in the reshaping of the cellular microenvironment. AGR2 thus plays a key role in inflammation and oncogenesis and may represent a therapeutic target of interest. In this review, we summarize the already known roles and mechanisms of action of the AGR family proteins in digestive diseases, their expression in the healthy digestive tract, and in digestive oncology. At last, we discuss the potential diagnostic and therapeutic implications underlying the biology of AGR proteins.

• MeSH
• gastrointestinální nádory * genetika   MeSH
• karcinogeneze genetika   MeSH
• mukoproteiny genetika   MeSH
• myši MeSH
• nádorové mikroprostředí MeSH
• onkogenní proteiny * genetika   MeSH
• proteindisulfidisomerasy MeSH
• zánět genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• mukoproteiny MeSH
• onkogenní proteiny * MeSH
• proteindisulfidisomerasy MeSH

Familial colorectal cancer (CRC) is only partially explained by known germline predisposing genes. We performed whole-genome sequencing in 15 Polish families of many affected individuals, without mutations in known CRC predisposing genes. We focused on loss-of-function variants and functionally characterized them. We identified a frameshift variant in the CYBA gene (c.246delC) in one family and a splice site variant in the TRPM4 gene (c.25-1 G > T) in another family. While both variants were absent or extremely rare in gene variant databases, we identified four additional Polish familial CRC cases and two healthy elderly individuals with the CYBA variant (odds ratio 2.46, 95% confidence interval 0.48-12.69). Both variants led to a premature stop codon and to a truncated protein. Functional characterization of the variants showed that knockdown of CYBA or TRPM4 depressed generation of reactive oxygen species (ROS) in LS174T and HT-29 cell lines. Knockdown of TRPM4 resulted in decreased MUC2 protein production. CYBA encodes a component in the NADPH oxidase system which generates ROS and controls, e.g., bacterial colonization in the gut. Germline CYBA variants are associated with early onset inflammatory bowel disease, supported with experimental evidence on loss of intestinal mucus barrier function due to ROS deficiency. TRPM4 encodes a calcium-activated ion channel, which, in a human colonic cancer cell line, controls calcium-mediated secretion of MUC2, a major component of intestinal mucus barrier. We suggest that the gene defects in CYBA and TRPM4 mechanistically involve intestinal barrier integrity through ROS and mucus biology, which converges in chronic bowel inflammation.

• Klíčová slova
• cancer predisposition, mucin, reactive oxygen species, whole-genome sequencing,
• Publikační typ
• časopisecké články MeSH

Colorectal cancer (CRC) is a heterogeneous disease that includes both hereditary and sporadic types of tumors. Tumor initiation and growth is driven by mutational or epigenetic changes that alter the function or expression of multiple genes. The genes predominantly encode components of various intracellular signaling cascades. In this review, we present mouse intestinal cancer models that include alterations in the Wnt, Hippo, p53, epidermal growth factor (EGF), and transforming growth factor β (TGFβ) pathways; models of impaired DNA mismatch repair and chemically induced tumorigenesis are included. Based on their molecular biology characteristics and mutational and epigenetic status, human colorectal carcinomas were divided into four so-called consensus molecular subtype (CMS) groups. It was shown subsequently that the CMS classification system could be applied to various cell lines derived from intestinal tumors and tumor-derived organoids. Although the CMS system facilitates characterization of human CRC, individual mouse models were not assigned to some of the CMS groups. Thus, we also indicate the possible assignment of described animal models to the CMS group. This might be helpful for selection of a suitable mouse strain to study a particular type of CRC.

• Klíčová slova
• carcinoma, consensus molecular subtypes, intestine, oncogenes, signaling cascades, tumor suppressors, tumorigenesis,
• MeSH
• epidermální růstový faktor genetika   MeSH
• geny p53 genetika   MeSH
• karcinogeneze genetika   MeSH
• kolorektální nádory klasifikace   metabolismus   patofyziologie   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• myši MeSH
• nádorová transformace buněk genetika   MeSH
• nádory tračníku genetika   MeSH
• oprava chybného párování bází DNA genetika   MeSH
• protein-serin-threoninkinasy genetika   MeSH
• regulace genové exprese u nádorů genetika   MeSH
• signální dráha Hippo MeSH
• signální dráha Wnt genetika   MeSH
• transformující růstový faktor beta genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• epidermální růstový faktor MeSH
• protein-serin-threoninkinasy MeSH
• transformující růstový faktor beta MeSH

Mucins and their glycosylation have been suggested to play an important role in colorectal carcinogenesis. We examined potentially functional genetic variants in the mucin genes or genes involved in their glycosylation with respect to colorectal cancer (CRC) risk and clinical outcome. We genotyped 23 single nucleotide polymorphisms (SNPs) covering 123 SNPs through pairwise linkage disequilibrium (r2>0.80) in the MUC1, MUC2, MUC4, MUC5AC, MUC6, and B3GNT6 genes in a hospital-based case-control study of 1532 CRC cases and 1108 healthy controls from the Czech Republic. We also analyzed these SNPs in relation to overall survival and event-free survival in a subgroup of 672 patients. Among patients without distant metastasis at the time of diagnosis, two MUC4 SNPs, rs3107764 and rs842225, showed association with overall survival (HR 1.40, 95%CI 1.08-1.82, additive model, log-rank p = 0.004 and HR 0.64, 95%CI 0.42-0.99, recessive model, log-rank p = 0.01, respectively) and event-free survival (HR 1.31, 95%CI 1.03-1.68, log-rank p = 0.004 and HR 0.64, 95%CI 0.42-0.96, log-rank p = 0.006, respectively) after adjustment for age, sex and TNM stage. Our data suggest that genetic variation especially in the transmembrane mucin gene MUC4 may play a role in the survival of CRC and further studies are warranted.

• MeSH
• doba přežití bez progrese choroby MeSH
• dospělí MeSH
• genotyp MeSH
• glykosylace MeSH
• jednonukleotidový polymorfismus genetika   MeSH
• Kaplanův-Meierův odhad MeSH
• kolorektální nádory genetika   mortalita   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mucin 4 genetika   metabolismus   MeSH
• muciny genetika   metabolismus   MeSH
• nádorové biomarkery genetika   MeSH
• nádory tračníku genetika   mortalita   patologie   MeSH
• přežití po terapii bez příznaků nemoci MeSH
• rizikové faktory MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• vazebná nerovnováha 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
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• MUC4 protein, human MeSH Prohlížeč
• mucin 4 MeSH
• muciny MeSH
• nádorové biomarkery MeSH