Project description:ObjectiveIBD confers an increased lifetime risk of developing colorectal cancer (CRC), and colitis-associated CRC (CA-CRC) is molecularly distinct from sporadic CRC (S-CRC). Here we have dissected the evolutionary history of CA-CRC using multiregion sequencing.DesignExome sequencing was performed on fresh-frozen multiple regions of carcinoma, adjacent non-cancerous mucosa and blood from 12 patients with CA-CRC (n=55 exomes), and key variants were validated with orthogonal methods. Genome-wide copy number profiling was performed using single nucleotide polymorphism arrays and low-pass whole genome sequencing on archival non-dysplastic mucosa (n=9), low-grade dysplasia (LGD; n=30), high-grade dysplasia (HGD; n=13), mixed LGD/HGD (n=7) and CA-CRC (n=19). Phylogenetic trees were reconstructed, and evolutionary analysis used to reveal the temporal sequence of events leading to CA-CRC.Results10/12 tumours were microsatellite stable with a median mutation burden of 3.0 single nucleotide alterations (SNA) per Mb, ~20%?higher than S-CRC (2.5 SNAs/Mb), and consistent with elevated ageing-associated mutational processes. Non-dysplastic mucosa had considerable mutation burden (median 47 SNAs), including mutations shared with the neighbouring CA-CRC, indicating a precancer mutational field. CA-CRCs were often near triploid (40%) or near tetraploid (20%) and phylogenetic analysis revealed that copy number alterations (CNAs) began to accrue in non-dysplastic bowel, but the LGD/HGD transition often involved a punctuated 'catastrophic' CNA increase.ConclusionsEvolutionary genomic analysis revealed precancer clones bearing extensive SNAs and CNAs, with progression to cancer involving a dramatic accrual of CNAs at HGD. Detection of the cancerised field is an encouraging prospect for surveillance, but punctuated evolution may limit the window for early detection.
Project description:Inflammatory bowel disease confers an increased lifetime risk of developing colorectal cancer (CRC), and colitis-associated CRC (CA-CRC) is molecularly distinct from sporadic CRC (S-CRC). Here we have dissected the evolutionary history of CA-CRC using multi-region sequencing.
Exome sequencing was performed on fresh-frozen multiple regions of carcinoma, adjacent non-cancerous mucosa and blood from 12 CA-CRC patients (n=55 exomes), and key variants were validated with orthogonal methods. Genome-wide copy number profiling was performed using SNP arrays and low-pass whole genome sequencing on archival non-dysplastic mucosa (n=9), low-grade dysplasia (LGD, n=30), high-grade dysplasia (HGD, n=13), mixed LGD/HGD (n=7) and CA-CRC (n=19). Phylogenetic trees were reconstructed, and evolutionary analysis used to reveal the temporal sequence of events leading to CA-CRC.
10/12 tumors were microsatellite stable with a median mutation burden of 3.0 single nucleotide alterations (SNAs) per Mb, around 20% higher than S-CRC (2.5 SNAs/Mb), and consistent with elevated aging-associated mutational processes. Non-dysplastic mucosa had considerable mutation burden (median 47 SNAs), including mutations shared with the neighboring CA-CRC, indicating a pre-cancer mutational field. CA-CRCs were often near-triploid (42%) or near-tetraploid (21%) and phylogenetic analysis revealed that copy number alterations (CNAs) began to accrue in non-dysplastic bowel, but the LGD/HGD transition often involved a punctuated catastrophic CNA increase.
Project description:Colorectal cancer is one of the most common and lethal cancers in the world. An important causative factor of colorectal cancer is ulcerative colitis. In this study, we investigated the therapeutic effects of piperlongumine (PL) on the dextran sulfate sodium (DSS)-induced acute colitis and azoxymethane (AOM)/DSS-induced colorectal cancer mouse models. Our results showed that PL could inhibit the inflammation of DSS-induced mouse colitis and reduce the number of large neoplasms (diameter >2 mm) of AOM/DSS-induced mouse colorectal cancer by downregulation of proinflammatory cytokines cyclooxygenase-2 and interleukin-6 and epithelial-mesenchymal transition-related factors, β-catenin, and snail expressions, but fail to improve the colitis symptoms and to decrease the incidence of colonic neoplasms and the number of small neoplasms (diameter <2 mm). These data suggested that PL might be an effective agent in treating colitis and colorectal cancer.
Project description:Cardamonin is a naturally occurring chalcone, majorly from the Zingiberaceae family, which includes a wide range of spices from India. Herein, we investigated the anti-inflammatory property of cardamonin using different in vitro and in vivo systems. In RAW 264.7 cells, treatment with cardamonin showed a reduced nitrous oxide production without affecting the cell viability and decreased the expression of iNOS, TNF-α, and IL-6, and inhibited NF-kB signaling which emphasizes the role of cardamonin as an anti-inflammatory molecule. In a mouse model of dextran sodium sulfate (DSS)-induced colitis, cardamonin treatment protected the mice from colitis. Subsequently, we evaluated the therapeutic potential of this chalcone in a colitis-associated colon cancer model. We performed microRNA profiling in the different groups and observed that cardamonin modulates miRNA expression, thereby inhibiting tumor formation. Together, our findings indicate that cardamonin has the potential to be considered for future therapy against colorectal cancer.
Project description:The effect of Cardamonin was checked on Dextran sulfate sodium and Azoxymethane (AOM) induced colon cancer in C57Bl/6 mice. C57Bl/6 were given a single AOM (10mg/kg B.wt) intraperitonielly at day 0 and three bouts of 5% DSS at days 5-10, 25-30, 45-50. At day 140, the mice were sacrificed and colon was monitored for tumors. Cardamonin treatment (10mg/Kg B.wt, p.o) was started simulatenously for one group. For the second group it was started after 16 of first AOM injection. The study was terminated at 140 day. The RNA was ioslated uisng mirVANA kit from each samples followed miRNA analysis uisng affymetrix gene chip miRNA array 4.0
Project description:MUC4, a large transmembrane mucin normally expressed in the small and large intestine, is differentially expressed during inflammatory and malignant conditions of the colon. However, the expression pattern and the role of MUC4 in colitis and colorectal cancer (CRC) are inconclusive. Therefore, the aim of this study was to understand the role of Muc4 during inflammatory and malignant conditions of the colon. Here, we generated Muc4(-/-) mice and addressed its role in colitis and colitis-associated CRC using dextran sodium sulfate (DSS) and azoxymethane (AOM)-DSS experimental models, respectively. Muc4(-/-) mice were viable, fertile with no apparent defects. Muc4(-/-) mice displayed increased resistance to DSS-induced colitis compared with wild-type (WT) littermates that was evaluated by survival rate, body weight loss, diarrhea and fecal blood score, and histological score. Reduced infiltration of inflammatory cells, that is, CD3(+) lymphocytes and F4/80(+) macrophages was observed in the inflamed mucosa along with reduction in the mRNA levels of inflammatory cytokines interleukin (IL)-1? and tumor necrosis factor (TNF)-? and anti-microbial genes Lysozyme M and SLPI in the colon of Muc4(-/-) mice compared with WT littermates. Compensatory upregulation of Muc2 and Muc3 mucins under basal and DSS treatment conditions partly explains the resistance observed in Muc4(-/-) mice. Accordingly, Muc4(-/-) mice exhibited significantly reduced tumor burden compared with WT mice assessed in a colitis-induced tumor model using AOM/DSS. An increased percentage of Ki67(+) nuclei was observed in the tumors from WT compared with Muc4(-/-) mice suggesting Muc4 to be critical in intestinal cell proliferation during tumorigenesis. Taken together, we conclusively demonstrate for the first time the role of Muc4 in driving intestinal inflammation and inflammation-associated tumorigenesis using a novel Muc4(-/-) mouse model.
Project description:The gut microbiota plays a major role in intestinal health, and an imbalance in its composition can lead to chronic gut inflammation and a predisposition to developing colorectal cancer (CRC). Currently, the use of probiotic bacteria represents an emerging alternative to treat and prevent cancer. Moreover, consumption of these beneficial bacteria may also favorably modulate the composition of the gut microbiota, which has been described in several studies to play an important role in CRC carcinogenesis. In this context, the aim of this study was to assess the protective effect of oral treatment with Lactobacillus casei BL23, a probiotic strain well known for its anti-inflammatory and anticancer properties. First, CRC was induced in C57BL6 mice by a single intraperitoneal injection with azoxymethane (8?mg/kg), followed by four courses of dextran sodium sulfate (2.5%) in drinking water that were separated by an adjustable recovery period. At the time of sacrifice (day 46), tumor incidence, histological scores, and epithelial proliferation were determined in colon samples. Our results show that L. casei BL23 significantly protected mice against CRC development; specifically, L. casei BL23 treatment reduced histological scores and proliferative index values. In addition, our analysis revealed that L. casei BL23 had an immunomodulatory effect, mediated through the downregulation of the IL-22 cytokine, and an antiproliferative effect, mediated through the upregulation of caspase-7, caspase-9, and Bik. Finally, L. casei BL23 treatment tended to counterbalance CRC-induced dysbiosis in mice, as demonstrated by an analysis of fecal microbiota. Altogether our results demonstrate the high potential of L. casei BL23 for the development of new, probiotic-based strategies to fight CRC.