Increased Th17-Related Cytokine Serum Levels in Patients With Multiple Polyps of Unexplained Origin

OBJECTIVES: Most patientswith multiple colonic polyps do not have a known genetic or hereditary origin. Our aim was to analyze the presence of inflammatory cytokines and levels of glucose, insulin, and C-reactive protein (CRP) in patients with multiple colonic polyps. METHODS: Eighty-three patients with 10 or more adenomatous or serrated polyps and 53 control people with normal colonoscopy were included. Smoking habits were registered, and glucose, CRP, and basal insulin in the serum/blood weremeasured. Quantification of IL-2, IL-4, IL-6, IL-10, IL-11, IL-17A, and IL-23 cytokine levels in the serum was performed by a high-sensitivity enzyme-linked immunosorbent assay. RESULTS: Smoking and diabetesweremore prevalent in those with colonic polyps than in the control people (67% vs 16%, P = 0.001; 11% vs 2%, P = 0.048). In addition, the cytokine serum levels were higher, i.e., IL-2 (P = 0.001), IL-4 (P = 0.001), IL-6 (P = 0.001), IL-17A (P = 0.001), IL-23 (P = 0.014), and CRP (P = 0.003). Adjusting for sex, smoking, and diabetes in amultivariate analysis, IL-2, IL-4, IL-6, IL-17A, and IL-23 remained independently elevated in cases with multiple polyps. DISCUSSION: These results indicate that immune responses mediated by Th17 cells may be involved in the pathogenesis of multiple colonic polyps

Increased Th17-Related Cytokine Serum Levels in Patients With Multiple Polyps of Unexplained Origin

OBJECTIVES: Most patients with multiple colonic polyps do not have a known genetic or hereditary origin. Our aim was to analyze the presence of inflammatory cytokines and levels of glucose, insulin, and C-reactive protein (CRP) in patients with multiple colonic polyps. METHODS: Eighty-three patients with 10 or more adenomatous or serrated polyps and 53 control people with normal colonoscopy were included. Smoking habits were registered, and glucose, CRP, and basal insulin in the serum/blood were measured. Quantification of IL-2, IL-4, IL-6, IL-10, IL-11, IL-17A, and IL-23 cytokine levels in the serum was performed by a high-sensitivity enzyme-linked immunosorbent assay. RESULTS: Smoking and diabetes were more prevalent in those with colonic polyps than in the control people (67% vs 16%, P = 0.001; 11% vs 2%, P = 0.048). In addition, the cytokine serum levels were higher, i.e., IL-2 (P = 0.001), IL-4 (P = 0.001), IL-6 (P = 0.001), IL-17A (P = 0.001), IL-23 (P = 0.014), and CRP (P = 0.003). Adjusting for sex, smoking, and diabetes in a multivariate analysis, IL-2, IL-4, IL-6, IL-17A, and IL-23 remained independently elevated in cases with multiple polyps. DISCUSSION: These results indicate that immune responses mediated by Th17 cells may be involved in the pathogenesis of multiple colonic polyps

Clinical and Pathological Characterization of Lynch-Like Syndrome

Background & aims: Lynch syndrome is characterized by DNA mismatch repair (MMR) deficiency. Some patients with suspected Lynch syndrome have DNA MMR deficiencies but no detectable mutations in genes that encode MMR proteins-this is called Lynch-like syndrome (LLS). There is no consensus on management of patients with LLS. We collected data from a large series of patients with LLS to identify clinical and pathology features. Methods: We collected data from a nationwide-registry of patients with colorectal cancer (CRC) in Spain. We identified patients whose colorectal tumors had loss of MSH2, MSH6, PMS2, or MLH1 (based on immunohistochemistry), without the mutation encoding V600E in BRAF (detected by real-time PCR), and/or no methylation at MLH1 (determined by methylation-specific multiplex ligation-dependent probe amplification), and no pathogenic mutations in MMR genes, BRAF, or EPCAM (determined by DNA sequencing). These patients were considered to have LLS. We collected data on demographic, clinical, and pathology features and family history of neoplasms. The χ2 test was used to analyze the association between qualitative variables, followed by the Fisher exact test and the Student t test or the Mann-Whitney test for quantitative variables. Results: We identified 160 patients with LLS; their mean age at diagnosis of CRC was 55 years and 66 patients were female (41%). The Amsterdam I and II criteria for Lynch syndrome were fulfilled by 11% of cases and the revised Bethesda guideline criteria by 65% of cases. Of the patients with LLS, 24% were identified in universal screening. There were no proportional differences in sex, indication for colonoscopy, immunohistochemistry, pathology findings, or personal history of CRC or other Lynch syndrome-related tumors between patients who met the Amsterdam and/or Bethesda criteria for Lynch syndrome and patients identified in universal screening for Lynch syndrome, without a family history of CRC. Conclusions: Patients with LLS have homogeneous clinical, demographic, and pathology characteristics, regardless of family history of CRC

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics

Novel Germline and somatic processes in mismatch repair deficient tumors

La inestabilidad de microatélites (MSI) está presente en diferentes tipos tumorales. Generalmente se explica por metilación del promotor de MLH1 o mutaciones germinales en los genes de reparación mismatch repair (MMR) del ADN, causando el conocido síndrome de Lynch. Recientemente, con el cribado universal se ha dado a conocer que un gran porcentaje de tumores con sospecha de síndrome de Lynch, no presentan estas mutaciones. Hasta la fecha, la hipótesis más aceptada para explicar este fenómeno conocido como síndrome Lynch-like, es la doble inactivación de estos genes a nivel somático. Aun así, estos pacientes presentan cáncer colorectal y otros tumores a edades tempranas y en muchos casos, se acompaña de una historia familiar de cáncer colorectal, que sugiere un origen hereditario. Objetivos: Elucitar las bases moleculares responsables de la pérdida de función del sistema MMR en casos de sospecha de Síndrome de Lycnh sin mutaciones germinales en estos genes. Estudio germinal: Identificar nuevas mutaciones germinales en genes reparadores del ADN que puedan estar implicadas en el desarrollo de inestabilidad de microsatélites. Estudio somático: Realizar una caracterización molecular de los tumores con MSI para identificar los eventos moleculares que pueden impactar el comportamiento tumoral y el manejo clínico. Materiales y métodos: Se analizó el exoma germinal de 100 muestras de pacientes Lynch-like y 30 Lynch. Adicionalmente se secuenciaron 37 tumores Lynch-like, 25 Lynch y se utilizó la información de 31 MSI/BRAF del TCGA. Las muestras fueron secuenciadas en Illumina HiSeq y analizadas en un High-performance computer siguiendo los estándares del Yale Center for Genome Analysis (YCGA). Resultados: Estudio germinal: Entre los Lynch-like encontramos 7 Lynch no identificados previamente. El 50% del MSI detectado en Lynch-like podía explicarse por dobles inactivación de los mismos a nivel somático. Además entre los Lynch-like encontramos 15 variantes germinales patogénicas que podían explicar la inestabilidad genética. Dos de ellas con inactivación del otro alelo a nivel somático. Además demostramos que la inactivación de un solo alelo es suficiente para tener un fenotipo deficiente. Estudio somático: no todos los tumores clasificados como MSI por MSI-PCR son presentan esta inestabilidad a nivel global. Al analizar diferentes tumores MSI descubrimos dos clústeres bien diferenciados en base a los perfiles mutacionales detectados. Buscamos mutaciones en genes reparadores y de predisposición al cáncer que pudieran estar marcando esas diferencias en las signatures. Discusión y conclusiones: Estudio germinal: Este estudio confirma el enriquecimiento existente en variantes germinales en los genes reparadores del ADN en pacientes con Síndrome Lynch-like. Variantes en estos genes, conferirían una deficiencia media heredada que promovería y podría inducir una inestabilidad genómica con el paso del tiempo. LA identificación de la variante en RECQL5 como potencial mutación asociada a un fenotipo de cáncer colorrectal familiar. Lynch-like es un grupo heterogéneo a nivel genético, con la característica común de ser MSI. Los tumores Lynch-like pueden ser causados por doble inactivación somática u otros defectos en otros genes reparadores. Además, el grupo incluye Lynch no identificados por los métodos de detección actuales. Estudio somático: Este estudio proporciona un valorable nueva perspectiva en los tumores con deficiencia en el sistema MMR. Muestra la correlación entre los diferentes niveles de MSI global y los perfiles mutacionales y clínicos, lo cual puede tener grandes implicaciones a nivel de diagnóstico y tratamiento de los pacientes

Lynch-like Syndrome: Potential Mechanisms and Management

Lynch syndrome is an autosomal dominant disorder caused by germline mutations in DNA mismatch repair (MMR) system genes, such as MLH1, MSH2, MSH6, or PMS2. It is the most common hereditary colorectal cancer syndrome. Screening is regularly performed by using microsatellite instability (MSI) or immunohistochemistry for the MMR proteins in tumor samples. However, in a proportion of cases, MSI is found or MMR immunohistochemistry is impaired in the absence of a germline mutation in MMR genes, BRAF mutation, or MLH1 hypermethylation. These cases are defined as Lynch-like syndrome. Patients with Lynch-like syndrome represent a mixture of truly hereditary and sporadic cases, with a risk of colorectal cancer in first-degree relatives that is between the risk of Lynch syndrome in families and relatives of sporadic colon cancer cases. Although multiple approaches have been suggested to distinguish between hereditary and sporadic cases, a homogeneous testing protocol and consensus on the adequate classification of these patients is still lacking. For this reason, management of Lynch-like syndrome and prevention of cancer in these families is clinically challenging. This review explains the concept of Lynch-like syndrome, potential mechanisms for its development, and methods for adequately distinguishing between sporadic and hereditary cases of this entity

A novel non-invasive colorectal cancer diagnostic method: Volatile organic compounds as biomarkers

Introduction: Population-based fecal tests for colorectal cancer (CRC) screening have shown to reduce mortality thanks to the early detection of the disease. However, currently available fecal tests are limited in their sensitivity and specificity. Our aim is to look for volatile organic compounds in fecal samples as biomarkers for CRC detection. Material and Methods: Eighty participants were included; 24 had adenocarcinoma, 24 had adenomatous polyps and 32 presented no neoplasms. Fecal samples were collected 48 h preceding the colonoscopy from all participants, except CRC patient samples that were collected after 3–4 weeks from the colonoscopy. Magnetic headspace adsorptive extraction (Mag-HSAE) followed by thermal desorption-gas chromatography-mass spectrometry (TD-GC–MS) was performed on stool samples to identify volatile organic compounds as biomarkers. Results: p-Cresol was significantly more abundant in the cancer samples (P < 0.001) with an area under the curve (AUC) of 0.85 (CI 95%; 0.737–0.953), having a sensitivity and specificity of 83% and 82%, respectively. In addition, 3(4H)-dibenzofuranone,4a,9b-dihydro-8,9b-dimethyl- (3(4H)-DBZ) was also more abundant in the cancer samples (P < 0.001) with an AUC of 0.77 (CI 95%; 0.635–0.905), sensitivity of 78% and specificity of 75%. When combined (p-cresol and 3(4H)-DBZ), the AUC was 0.86, sensitivity 87% and specificity 79%. p-Cresol also appeared to be promising as a biomarker for pre-malignant lesions with an AUC of 0.69 (CI 95%; 0.534–0.862), sensitivity 83% and specificity 63%, P = 0.045. Conclusions: Volatile organic compounds emitted from feces and determined by a sensitive analytical methodology (Mag-HSAE-TD-GC–MS), employing a magnetic graphene oxide as extractant phase, could be used as a potential screening technology for CRC and pre-malignant lesions.Miren Alustiza would like to thank ISABIAL for her pre-doctoral grant (UGP-16-138/2016/45). This work was supported by the Instituto de Salud Carlos III (PI17/01756, PI20/01527); by Vicerrectorado de Investigación y de Transferencia de Conocimiento (UAUSTI18-04, UAUSTI19-05, UAUSTI20-04), and Conselleria d’Innovació, Universitats, Ciència i Societat Digital (Generalitat Valenciana) (PROMETEO/2018/087; CIPROM/2021/062). The authors extend their appreciation to the Ministry of Science, Innovation and Universities for granting the Spanish Network of Excellence in Sample Preparation (RED2018-102522-T)

Effects of Somatic Methylation in Colonic Polyps on Risk of Developing Metachronous Advanced Colorectal Lesions

The utility of molecular markers for predicting the risk of metachronous advanced colorectal lesions (MACLs) remains poorly investigated. We examined the relationship between somatic hypermethylation in polyps at baseline and the risk of developing MACL. This retrospective cohort study included 281 consecutive patients with colonic polyps who were enrolled between 2007 and 2009 and followed-up until 2014. MACLs were defined as adenomas of ≥10 mm, high-grade dysplasia, or with a villous component; and serrated lesions of ≥10 mm or with dysplasia. In total, 595 polyps were removed at baseline colonoscopy and analyzed for pathological characteristics and CpG island methylator phenotype (CIMP) using the MS-MLPA (Methylation-Specific -- Multiplex Ligation-dependent Probe Amplification) technique. Forty-five patients (16.0%) showed at least one CIMP+ polyp. MACL risk was higher in patients with CIMP+ polyps (odds ratio (OR), 4.50; 95% CI, 1.78–11.4; p = 0.002). Patients with CIMP+ polyps also exhibited shorter time to MACL development (33.8 months vs. 50.1 months; p < 0.001), even with adjustment for polyp size and number (OR, 2.40; 95% CI, 1.33–4.34). Adding CIMP analysis improved the sensitivity (57.0% to 70.9%), negative predictive value (71.1% to 77.3%), and overall accuracy (49.8% to 52.0%) for MACL risk estimation. These results highlight that CIMP may be a useful marker for endoscopic surveillance

KRAS and BRAF somatic mutations in colonic polyps and the risk of metachronous neoplasia.

High-risk features of colonic polyps are based on size, number, and pathologic characteristics. Surveillance colonoscopy is often recommended according to these findings. This study aimed to determine whether the molecular characteristics of polyps might provide information about the risk of metachronous advanced neoplasia.We retrospectively included 308 patients with colonic polyps. A total of 995 polyps were collected and tested for somatic BRAF and KRAS mutations. Patients were classified into 3 subgroups, based on the polyp mutational profile at baseline, as follows: non-mutated polyps (Wild-type), at least one BRAF-mutated polyp, or at least one KRAS-mutated polyp. At surveillance, advanced adenomas were defined as adenomas ≥ 10 mm and/or with high grade dysplasia or a villous component. In contrast, advanced serrated polyps were defined as serrated polyps ≥ 10 mm in any location, located proximal to the splenic flexure with any size or with dysplasia.At baseline, 289 patients could be classified as wild-type (62.3%), BRAF mutated (14.9%), or KRAS mutated (22.8%). In the univariate analysis, KRAS mutations were associated with the development of metachronous advanced polyps (OR: 2.36, 95% CI: 1.22-4.58; P = 0.011), and specifically, advanced adenomas (OR: 2.42, 95% CI: 1.13-5.21; P = 0.023). The multivariate analysis, adjusted for age and sex, also showed associations with the development of metachronous advanced polyps (OR: 2.27, 95% CI: 1.15-4.46) and advanced adenomas (OR: 2.23, 95% CI: 1.02-4.85).Our results suggested that somatic KRAS mutations in polyps represent a potential molecular marker for the risk of developing advanced neoplasia