Ulrik Lindforss

miR-185 and miR-133b deregulation is associated with overall survival and metastasis in colorectal cancer.

Colorectal cancer (CRC) is one of the most common and deadly forms of cancer. Despite improved treatment modalities, post-operative recurrence and metastasis remain the major problems for extending patient survival after surgery. This highlights the need to search for biomarkers for prognostication and treatment stratification of colorectal cancer patients. In this study, we applied the SYBR-green quantitative PCR-based array approach to screen for differentially expressed miRNAs between patients with short (<50 months, range 10-33 months) and long survival (≥ 50 months, range 50-152 months). The selected candidate prognostic miRNAs were validated in a cohort of 50 CRC patients by TaqMan quantitative PCR. We found that high expression of miR-185 and low expression of miR-133b were correlated with poor survival (p=0.001 and 0.028, respectively) and metastasis (p=0.007 and 0.036, respectively) in colorectal cancer. Our findings suggest the potential prognostic values of these miRNAs for predicting clinical outcome after surgery.

Association studies on 11 published colorectal cancer risk loci

Background:Recently, several genome-wide association studies (GWAS) have independently found numerous loci at which common single-nucleotide polymorphisms (SNPs) modestly influence the risk of developing colorectal cancer. The aim of this study was to test 11 loci, reported to be associated with an increased or decreased risk of colorectal cancer: 8q23.3 (rs16892766), 8q24.21 (rs6983267), 9p24 (rs719725), 10p14 (rs10795668), 11q23.1 (rs3802842), 14q22.2 (rs4444235), 15q13.3 (rs4779584), 16q22.1 (rs9929218), 18q21.1 (rs4939827), 19q13.1 (rs10411210) and 20p12.3 (rs961253), in a Swedish-based cohort.Methods:The cohort was composed of 1786 cases and 1749 controls that were genotyped and analysed statistically. Genotype–phenotype analysis, for all 11 SNPs and sex, age of onset, family history of CRC and tumour location, was performed.Results:Of eleven loci, 5 showed statistically significant odds ratios similar to previously published findings: 8q23.3, 8q24.21, 10p14, 15q13.3 and 18q21.1. The remaining loci 11q23.1, 16q22.1, 19q13.1 and 20p12.3 showed weak trends but somehow similar to what was previously published. The loci 9p24 and 14q22.2 could not be confirmed. We show a higher number of risk alleles in affected individuals compared to controls. Four statistically significant genotype–phenotype associations were found; the G allele of rs6983267 was associated to older age, the G allele of rs1075668 was associated with a younger age and sporadic cases, and the T allele of rs10411210 was associated with younger age.Conclusions:Our study, using a Swedish population, supports most genetic variants published in GWAS. More studies are needed to validate the genotype–phenotype correlations.

Lack of an Association between the TGFBR1*6A Variant and Colorectal Cancer Risk

Purpose: Recently a common variant of the TGFBR1 gene, TGFBR1*6A, has been proposed to act as a low-penetrance tumor susceptibility allele for colorectal cancer, but data from published studies with individually low statistical power are conflicting. To further evaluate the relationship between TGFBR1*6A and colorectal cancer risk, we have conducted a large case-control study and a meta-analysis of previously published studies. Experimental Design: A total of 1,042 colorectal cancer cases and 856 population controls were genotyped for the TGFBR1*6A polymorphism. Previously published case-control studies of the relationship between TGFBR1*6A and colorectal cancer were identified, and a meta-analysis was conducted. Results: We found no evidence that homozygosity, heterozygosity or carrier status for the TGFBR1*6A allele confers an increased risk of colorectal cancer; respective odds ratios (OR) were 1.05 [95% confidence interval (95% CI), 0.83-1.32], 0.82 (95% CI, 0.34-1.99), and 0.92 (95% CI, 0.74-1.15), respectively. A meta-analysis of our case-control study and seven other studies that provided data on 2,627 colorectal cancer cases and 3,387 controls also yielded no evidence that possession of the TGFBR1*6A allele is associated with an elevated risk of colorectal cancer; pooled estimate of the OR were 1.20 (95% CI, 0.64-2.24) for homozygosity, 1.11 (95% CI, 0.96-1.29) for heterozygosity, and 1.13 (95% CI, 0.98-1.30) for carriers of TGFBR1*6A. Conclusion: Current data provide limited support for the hypothesis that sequence variation in TGFBR1 defined by the TGFBR1*6A allele confers an elevated risk of colorectal cancer.

Contribution of CARD15 variants in determining susceptibility to Crohn's disease in Sweden.

Objective. Crohns disease (CD) is a chronic inflammatory bowel disorder caused by environmental and genetic factors. Mutations in the CARD15 gene have been associated with CD. No previous case-control CARD15 study has been performed in the Swedish population. Material and methods. The study comprised of 321 individuals: 178 with CD and 143 healthy controls (HCs), all from Stockholm County. All were genotyped for the three main CD-associated CARD15 variants (R702W, G908R and 1007fs) and phenotypic associations were investigated. Results. The allele frequencies of the R702W variant (4.5% CD versus 0.7% HC, p=0.008, OR = 6.8) and the G908R variant (2.0% CD versus 0% HC, p=0.045) were more common in CD patients than in controls. No significant difference in1007fs variant allele frequency was found between CD patients and controls (2.0% CD versus 1.7% HC, p = 0.8, OR = 1.1). Carriage of CARD15 variants was more common in the CD patients than in controls (15.2% CD versus 4.2% HC, p = 0.001, OR = 4.1, population attributable risk (PAR) = 11.4%). Genotype–phenotype analysis demonstrated that CARD15 variants were associated with ileal disease (p=0.0006, OR = 9.3, CI = 2.2–34) and protective for colonic CD (p = 0.01, OR = 0.18). An association between CARD15 variants and ileal CD (p=0.004, OR = 6.6) was confirmed by multivariate analyses. Conclusions. The CARD15 variants R702W and G908R, but not 1007fs, are associated with susceptibility to CD in Stockholm County. Genotype–phenotype analysis shows an association with ileal CD. The contribution of these CARD15 mutations in Swedish CD patients overall is low in relation to studies elsewhere in Central Europe and North America, but is consistent with emerging data from elsewhere in Scandinavia and in Northern Europe.

Cancer risk assessment in long-standing pouchitis. DNA aberrations are rare in transformed neoplastic pelvic pouch mucosa.

Abstract.Background: In a small subgroup of patients with ulcerative colitis (UC) undergoing proctocolectomy and restorative ileal pouch-anal anastomosis (IPAA), a colonic-like pouch mucosa with severe and persistent villous atrophy (type C pattern) develops. Neoplastic transformation of the mucosa in the neorectum may occur in these patients. We hypothesized that genetic alterations associated with colorectal carcinoma (CRC) could be an early finding in this transformational process and thus potentially useful as clinical monitors in carcinoma risk assessment. Methods: In six patients with long-standing severe pouchitis and a type C-pattern mucosa, biopsies were obtained from five different locations of the pouches. DNA was PCR-amplified and analyzed by automated fragment analysis for loss of heterozygosity (LOH) at chromosome 5q14–22, 17p12–13, and 18q12–22. Point mutations of the K-ras and adenomatous polyposis coli (APC) genes were studied by sequencing. Results: The patients had varying degrees of dysplasia and one displayed DNA aneuploidy. Loss of heterozygosity at 5q15–22 was detected in three of five biopsies in one patient. This particular patient had no signs of dysplasia or DNA aneuploidy and a normal exon 15 sequence of the APC gene. No alterations of either the K-ras or the APC genes or LOH of 5q, 17p, or 18q were seen in any of the other patients. Conclusion: Dysplasia, aneuploidy, and LOH in 5q may all reflect different parts of an atrophic mucosa-dysplasia-carcinoma sequence, in line with current concepts of carcinogenesis for CRC in longstanding pouchitis. Further studies of histological and molecular events in IPAA patients with severe atrophy are warranted.

Contribution of the IBD5 locus to Crohn's disease in the Swedish population

Objective. Recent data have controversially suggested that variants of the organic cation transport genes SLC22A4 (OCTN1) and SLC22A5 (OCTN2) are responsible for the contribution of IBD5 to disease susceptibility in Crohns disease (CD). The objective of this study was to assess the contribution of the SLC22A4 variant (1672C→T) and SLC22A5 variant (−207G→C) together with three IBD5 haplotype markers in the previously uninvestigated Swedish CD population. Material and methods. The study comprised 178 CD patients and 143 healthy controls (HC). Genotyping for IBD5 single nucleotide polymorphisms (SNPs) IGR2096a_1, IGR2198a_1, IGR2230a_1, SLC22A4 1672C→T and SLC22A5 −207G→C was carried out using the TaqMan® system. Associations with disease susceptibility and disease phenotype were investigated. Results. Strong linkage disequilibrium was observed between the investigated SNPs (D prime >0.92). IGR2096a_1 allelic frequency and homozygosity rates were associated with CD (44% CD versus 33.8% HC, p =0.008, OR =1.55 and 20% CD versus 12% HC, p =0.04, OR =1.93, respectively). Variant allelic frequency of SLC22A4, 1672C→T (44% versus 36%, p =0.03, OR =1.4) and homozygosity for the SLC22A4, SLC22A5 TC haplotype (1672C→T, −207G→C) (21.3% versus 12%, p =0.03, OR =1.78, population attributable risk (PAR) =11%) were associated with CD. There was no association between the allelic frequency of SLC22A5 and CD (46.6% CD versus 41.5% HC, p =0.82). The association of the TC haplotype with CD was not independent of the SNPs representing the extended IBD5 linkage interval. Conclusions. The IBD5 locus is associated with CD in the Swedish population. The strongest association is with the marker SNP IGR2096a_1, lying p-telomeric to SLC22A4 and SLC22A5. The effect of the TC haplotype was not an independent determinant in this population.

Tissue-infiltrating neutrophils represent the main source of IL-23 in the colon of patients with IBD

Objective In IBD, interleukin-23 (IL-23) and its receptor (IL-23R) are implicated in disease initiation and progression. Novel insight into which cells produce IL-23 at the site of inflammation at an early stage of IBD will promote the development of new tools for diagnosis, treatment and patient monitoring. We examined the cellular source of IL-23 in colon tissue of untreated newly diagnosed paediatric patients with IBD. Design Colon tissues from IBD and non-IBD patients were analysed by quantitative real-time PCR (qPCR), immunofluorescence confocal microscopy and flow cytometry after appropriate sample preparation. Blood samples from IBD and non-IBD patients and healthy controls were analysed using flow cytometry and qPCR. Results We discovered that tissue-infiltrating neutrophils were the main source of IL-23 in the colon of paediatric patients with IBD, while IL-23+ human leucocyte antigen-DR+ or IL-23+CD14+ cells were scarce or non-detectable, respectively. The colonic IL-23+ neutrophils expressed C-X-C motif (CXC)R1 and CXCR2, receptors for the CXC ligand 8 (CXCL8) chemokine family, and a corresponding CXCR1+CXCR2+IL-23+subpopulation of neutrophils was also identified in the blood of both patients with IBD and healthy individuals. However, CXCL8-family chemokines were only elevated in colon tissue from patients with IBD. Conclusions This study provides the first evidence of CXCR1+CXCR2+IL-23-producing neutrophils that infiltrate and accumulate in inflamed colon tissue of patients with IBD. Thus, this novel source of IL-23 may play a key role in disease progression and will be important to take into consideration in the development of future strategies to monitor, treat and prevent IBD.

Clinicopathological analysis of colorectal cancer: a comparison between emergency and elective surgical cases

BackgroundApproximately 15 to 30% of colorectal cancers present as an emergency, most often as obstruction or perforation. Studies report poorer outcome for patients who undergo emergency compared with elective surgery, both for their initial hospital stay and their long-term survival. Advanced tumor pathology and tumors with unfavorable histologic features may provide the basis for the difference in outcome. The aim of this study was to compare the clinical and pathologic profiles of emergency and elective surgical cases for colorectal cancer, and relate these to gender, age group, tumor location, and family history of the disease. The main outcome measure was the difference in morphology between elective and emergency surgical cases.MethodsIn total, 976 tumors from patients treated surgically for colorectal cancer between 2004 and 2006 in Stockholm County, Sweden (8 hospitals) were analyzed in the study. Seventeen morphological features were examined and compared with type of operation (elective or emergency), gender, age, tumor location, and family history of colorectal cancer by re-evaluating the histopathologic features of the tumors.ResultsIn a univariate analysis, the following characteristics were found more frequently in emergency compared with elective cases: multiple tumors, higher American Joint Committee on Cancer (AJCC), tumor (T) and node (N) stage, peri-tumor lymphocytic reaction, high number of tumor-infiltrating lymphocytes, signet-ring cell mucinous carcinoma, desmoplastic stromal reaction, vascular and perineural invasion, and infiltrative tumor margin (P<0.0001 for AJCC stage III to IV, N stage 1 to 2/3, and vascular invasion). In a multivariate analysis, all these differences, with the exception of peri-tumor lymphocytic reaction, remained significant (P<0.0001 for multiple tumors, perineural invasion, infiltrative tumor margin, AJCC stage III, and N stage 1 to 2/3).ConclusionsColorectal cancers that need surgery as an emergency case generally show a more aggressive histopathologic profile and a more advanced stage than do elective cases. Essentially, no difference was seen in location, and therefore it is likely there would be no differences in macro-environment either. Our results could indicate that colorectal cancers needing emergency surgery belong to an inherently specific group with a different etiologic or genetic background.

Vitamin D downregulates the IL-23 receptor pathway in human mucosal group 3 innate lymphoid cells

&NA; Figure. No caption available. Background: Vitamin D deficiency is a risk factor for inflammatory bowel disease (IBD). The IL‐23–driven tissue‐resident group 3 innate lymphoid cells (ILC3s) play essential roles in intestinal immunity, and targeting IL‐23/12 is a promising approach in IBD therapy. Objective: We set out to define the role of 1&agr;,25‐dihydroxy vitamin D3 (1,25D) in regulating functional responses of human mucosal ILC3s to IL‐23 plus IL‐1&bgr; stimulation. Methods: Transcriptomes of sorted tonsillar ILC3s were assessed by using microarray analysis. ILC3 cytokine production, proliferation, and differentiation were determined by means of flow cytometry, ELISA, and multiplex immunoassay. Intestinal cell suspensions and ILC3s sorted from gut biopsy specimens of patients with IBD were also analyzed along with plasma 25‐hydroxy vitamin D3 (25D) detection. Results: ILC3s stimulated with IL‐23 plus IL‐1&bgr; upregulated the vitamin D receptor and responded to 1,25D with downregulation of the IL‐23 receptor pathway. Consequently, 1,25D suppressed IL‐22, IL‐17F, and GM‐CSF production from tonsillar and gut ILC3s. In parallel, 1,25D upregulated genes linked to the IL‐1&bgr; signaling pathway, as well as the IL‐1&bgr;–inducible cytokines IL‐6, IL‐8, and macrophage inflammatory protein 1&agr;/&bgr;. The 1,25D‐triggered skewing in ILC3 function was not accompanied or caused by changes in viability, proliferation, or phenotype. Finally, we confirmed low 25D plasma levels in patients with IBD with active inflammation. Conclusion: In light of the beneficial targeting of IL‐23/12 in patients with IBD, 1,25D appears as an interesting therapeutic agent that inhibits the IL‐23 receptor pathway, providing a novel mechanism for how ILC3s could be manipulated to regulate intestinal inflammation.

Colorectal Cancer Susceptibility Loci in a Population-Based Study : Associations with Morphological Parameters

Recent genome-wide association studies have identified multiple genetic loci and single nucleotide polymorphisms (SNPs) associated with either increased or decreased risk of colorectal cancer (CRC). In the present study, our objective was to determine whether 11 of the new susceptibility CRC loci are associated with tumor morphology and to confirm these loci as distinct and etiologically different risk factors in the development of CRC. The following clinical and morphological parameters were analyzed in 1572 samples: tumor size, T-stage, lymph node metastases, degree of differentiation, mucin production, Crohn-like peritumoral lymphocytic infiltration, tumor-infiltrating lymphocytes, desmoplastic reaction, necrosis, invasion of blood or lymph vessels, perineural growth, medullary type, budding, and tumor margin. One SNP from each of the 11 loci (rs6983267 on 8q24.21, rs16892766 on 8q23.3, rs719725 on 9p24.1, rs10795668 on 10p14, rs3802842 on 11q23.1, rs4444235 on 14q22.2, rs4779584 on 15q13.3, rs9929218 on 16q22.1, rs4939827 on 18q21.1, rs10411210 on 19q13.11, and rs961253 on 20p12.3) was genotyped for all cases. Odds ratios, 95% confidence intervals, and the corresponding P values were calculated for the 11 SNPs identified above. A cross tabulation between SNPs and morphology was performed. Several loci showed statistically significant associations with specific phenotypes. The findings are consistent with pathogenic variants in several loci that act in distinct CRC and morphogenetic pathways. Further large-scale studies are required to validate these findings.