Microbiomic and Metabolomic Analyses Unveil the Protective Effect of Saffron in a Mouse Colitis Model.

Despite the existence of effective drugs used to treat inflammatory bowel disease (IBD), many patients fail to respond or lose response over time. Further, many drugs can carry serious adverse effects, including increased risk of infections and malignancies. Saffron (Crocus sativus) has been reported to have anti-inflammatory properties. Its protective role in IBD and how the microbiome and metabolome play a role has not been explored extensively. We aimed to establish whether saffron treatment modulates the host microbiome and metabolic profile in experimental colitis. Colitis was induced in C57BL/6 mice with 3% DSS and treated with either saffron in a dose of 20 mg/kg body weight or vehicle through daily gavage. On day 10, stool pellets from mice were collected and analyzed to assess saffron's effect on fecal microbiota and metabolites through 16S rRNA sequencing and untargeted primary metabolite analysis. Saffron treatment maintained gut microbiota homeostasis by counter-selecting pro-inflammatory bacteria and maintained Firmicutes/Bacteroides ratio, which was otherwise disturbed by DSS treatment. Several metabolites (uric acid, cholesterol, 2 hydroxyglutaric acid, allantoic acid, 2 hydroxyhexanoic acid) were altered significantly with saffron treatment in DSS-treated mice, and this might play a role in mediating saffron's colitis-mitigating effects. These data demonstrate saffron's therapeutic potential, and its protective role is modulated by gut microbiota, potentially acting through changes in metabolites.

Pediatric COVID-19 and Gastrointestinal Symptoms in Africa.

One year into the coronavirus disease 2019 (COVID-19) pandemic, the African continent still seems to be spared from the devastating effects the disease had in other continents. Africa's COVID-19 seems to be of a milder nature both in adults and children. However, lack of data from Africa is significant, and more studies are needed to validate the disease status, clinical manifestations, and future implications for Africa. In this study, we report pediatric COVID-19 features in Africa represented by 8 countries.

Symptomatic, clinical and biomarker associations for mortality in hospitalized COVID-19 patients enriched for African Americans.

BACKGROUND AND AIMS: Initial reports on US COVID-19 showed different outcomes in different races. In this study we use a diverse large cohort of hospitalized COVID-19 patients to determine predictors of mortality. METHODS: We analyzed data from hospitalized COVID-19 patients (n = 5852) between March 2020- August 2020 from 8 hospitals across the US. Demographics, comorbidities, symptoms and laboratory data were collected. RESULTS: The cohort contained 3,662 (61.7%) African Americans (AA), 286 (5%) American Latinx (LAT), 1,407 (23.9%), European Americans (EA), and 93 (1.5%) American Asians (AS). Survivors and non-survivors mean ages in years were 58 and 68 for AA, 58 and 77 for EA, 44 and 61 for LAT, and 51 and 63 for AS. Mortality rates for AA, LAT, EA and AS were 14.8, 7.3, 16.3 and 2.2%. Mortality increased among patients with the following characteristics: age, male gender, New York region, cardiac disease, COPD, diabetes mellitus, hypertension, history of cancer, immunosuppression, elevated lymphocytes, CRP, ferritin, D-Dimer, creatinine, troponin, and procalcitonin. Use of mechanical ventilation (p = 0.001), shortness of breath (SOB) (p < 0.01), fatigue (p = 0.04), diarrhea (p = 0.02), and increased AST (p < 0.01), significantly correlated with death in multivariate analysis. Male sex and EA and AA race/ethnicity had higher frequency of death. Diarrhea was among the most common GI symptom amongst AAs (6.8%). When adjusting for comorbidities, significant variables among the demographics of study population were age (over 45 years old), male sex, EA, and patients hospitalized in New York. When adjusting for disease severity, significant variables were age over 65 years old, male sex, EA as well as having SOB, elevated CRP and D-dimer. Glucocorticoid usage was associated with an increased risk of COVID-19 death in our cohort. CONCLUSION: Among this large cohort of hospitalized COVID-19 patients enriched for African Americans, our study findings may reflect the extent of systemic organ involvement by SARS-CoV-2 and subsequent progression to multi-system organ failure. High mortality in AA in comparison with LAT is likely related to high frequency of comorbidities and older age among AA. Glucocorticoids should be used carefully considering the poor outcomes associated with it. Special focus in treating patients with elevated liver enzymes and other inflammatory biomarkers such as CRP, troponin, ferritin, procalcitonin, and D-dimer are required to prevent poor outcomes.

Protective Effect of Saffron in Mouse Colitis Models Through Immune Modulation.

BACKGROUND: People with inflammatory bowel disease (IBD) including ulcerative colitis are at risk for colorectal cancer. Despite available effective drugs used to treat IBD, many patients fail or lose response over time with some displaying drug-induced adverse events. Saffron (Crocus sativus) has been reported to have anti-inflammatory properties. Its protective role in IBD has not been explored extensively. AIM: To establish whether saffron treatment alleviates inflammation in experimental colitis. METHODS: Colitis was induced in C57BL/6 mice with 3% DSS and treated with either saffron doses (7.5, 15, 20, 25 mg/kg body weight) or vehicle through daily gavage. On day 11, mice were euthanized and analyzed for gross and microscopic inflammation. Distal colon segments were collected for mRNA and protein expression of HO-1 protein and GPX2, (the downstream targets of NRF-2). Nrf-2 translocation from cytosol to nucleus was confirmed by immunofluorescence, and further Nrf-2 protein expression in nuclear and cytosolic fraction of colon was analyzed by immunoblot. Immune cells were isolated from the lamina propria of mouse colon for flow cytometry-based immunophenotyping. Colitis was also induced in C57BL/6 Ahr knockout and wild type mice to explore the involvement of Ahr-dependent pathways in saffron's protective effect(s). The therapeutic effect of saffron was further validated in another TNBS model of colitis. RESULTS: Saffron 20 mg/kg body weight showed improved colon gross and histology features and led to better body weight, colon length, histology score, and reduced disease activity index (DAI). Saffron significantly decreased pro-inflammatory macrophages (M1), while increasing anti-inflammatory macrophages (M2) and IL10 + dendritic cells. Saffron treatment also enhanced CD3 + T and CD3 + CD8 + T cells followed by increase in different CD3 + CD4 + T cells subsets like CD25 + T cells, FoxP3 + CD25 + regulatory T cells, and CD4 + FOXP3 + CD25-regulatory T cells. Immunoblot analysis showed a significant increase in HO-1/GPX2 protein expression. With saffron treatment, Nrf-2 translocation into nucleus from cytosol also supports the involvement of Nrf-2 and its downstream targets in the protective effect of saffron. Further, we demonstrated that saffron in part exert anti-inflammatory effect through activation of aryl hydrocarbon receptor (AhR)-nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent pathways. CONCLUSION: These data demonstrate saffron's therapeutic potential and its protective role in part via Ahr/Nrf-2 pathways and regulatory innate and adaptive immune cells.

COVID-19 and gastrointestinal symptoms in Mexico, a systematic review: does location matter?

BACKGROUND: Covid-19 in Mexico is on the rise in different parts of the country. We aimed to study the symptoms and comorbidities that associate with this pandemic in 3 different regions of Mexico. METHODS: We analyzed data from SARS-CoV-2 positive patients evaluated at healthcare centers and hospitals of Mexico (n = 1607) including Northwest Mexico (Sinaloa state), Southeast Mexico (Veracruz state) and West Mexico (Jalisco state) between March 1 and July 30, 2020. Mexico consists of a total population that exceeds 128 million. Demographics, comorbidities and clinical symptoms were collected. Statistical descriptive analysis and correlation analyses of symptoms, comorbidities and mortality were performed. RESULTS: A total of 1607 hospitalized patients positive for COVID-19 across all 3 regions of Mexico were included. The average age was 54.6 years and 60.4% were male. A mortality rate of 33.1% was observed. The most common comorbidities were hypertension (43.2%), obesity (30.3%) and diabetes (31.4%). Hypertension was more frequent in West (45%), followed by Northwest (37%) and Southeast Mexico (29%). Obesity was around 30% in Northwest and West whereas an 18% was reported in Southeast. Diabetes was most common in West (34%) followed by Northwest (22%) and Southeast (13%). This might be related to the highest mortality rate in Northwest (31%) and West (37%) when compared to Southeast. Most common symptoms in our overall cohort were fever (80.8%), cough (79.8%), headache (66%), dyspnea (71.1%), myalgia (53.8%), joints pain (50.8%) and odynophagia (34.8%). Diarrhea was the main gastrointestinal (GI) symptom (21.3%), followed by abdominal pain (18%), and nausea/ vomiting (4.5%). Diarrhea and abdominal pain were more common in West (23.1 and 21%), followed by Southeast (17.8, and 9.8%) and Northwest (11.4 and 3.1%). CONCLUSION: Our study showed a high mortality rate likely related to high frequencies of comorbidities (hypertension, obesity and diabetes). Mortality was different across regions. These discrepancies might be related to the differences in the frequencies of comorbidities, and partially attributed to differences in socio-economic conditions and quality of care. Thus, our findings stress the need for improved strategies to get better outcomes in our population.

Saffron and Its Major Ingredients' Effect on Colon Cancer Cells with Mismatch Repair Deficiency and Microsatellite Instability.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide. One of its subtypes is associated with defective mismatch repair (dMMR) genes. Saffron has many potentially protective roles against colon malignancy. However, these roles in the context of dMMR tumors have not been explored. In this study, we aimed to investigate the effects of saffron and its constituents in CRC cell lines with dMMR. METHODS: Saffron crude extracts and specific compounds (safranal and crocin) were used in the human colorectal cancer cell lines HCT116, HCT116+3 (inserted MLH1), HCT116+5 (inserted MSH3), and HCT116+3+5 (inserted MLH1 and MSH3). CDC25b, p-H2AX, TPDP1, and GAPDH were analyzed by Western blot. Proliferation and cytotoxicity were analyzed by MTT. The scratch wound assay was also performed. RESULTS: Saffron crude extracts restricted (up to 70%) the proliferation in colon cells with deficient MMR (HCT116) compared to proficient MMR. The wound healing assay indicates that deficient MMR cells are doing better (up to 90%) than proficient MMR cells when treated with saffron. CDC25b and TDP1 downregulated (up to 20-fold) in proficient MMR cells compared to deficient MMR cells, while p.H2AX was significantly upregulated in both cell types, particularly at >10 mg/mL saffron in a concentration-dependent manner. The reduction in cellular proliferation was accompanied with upregulation of caspase 3 and 7. The major active saffron compounds, safranal and crocin reproduced most of the saffron crude extracts' effects. CONCLUSIONS: Saffron's anti-proliferative effect is significant in cells with deficient MMR. This novel effect may have therapeutic implications and benefits for MSI CRC patients who are generally not recommended for the 5-fluorouracil-based treatment.

Saffron Pre-Treatment Promotes Reduction in Tissue Inflammatory Profiles and Alters Microbiome Composition in Experimental Colitis Mice.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract with an incompletely understood pathogenesis. Long-standing colitis is associated with increased risk of colon cancer. Despite the availability of various anti-inflammatory and immunomodulatory drugs, many patients fail to respond to pharmacologic therapy and some experience drug-induced adverse events. Dietary supplements, particularly saffron (Crocus sativus), have recently gained an appreciable attention in alleviating some symptoms of digestive diseases. In our study, we investigated whether saffron may have a prophylactic effect in a murine colitis model. Saffron pre-treatment improved the gross and histopathological characteristics of the colonic mucosa in murine experimental colitis. Treatment with saffron showed a significant amelioration of colitis when compared to the vehicle-treated mice group. Saffron treatment significantly decreased secretion of serotonin and pro-inflammatory cytokines, such as TNF-α, IL-1ß, and IL-6, in the colon tissues by suppressing the nuclear translocation of NF-κB. The gut microbiome analysis revealed distinct clusters in the saffron-treated and untreated mice in dextran sulfate sodium (DSS)-induced colitis by visualization of the Bray-Curtis diversity by principal coordinates analysis (PCoA). Furthermore, we observed that, at the operational taxonomic unit (OTU) level, Cyanobacteria were depleted, while short-chain fatty acids (SCFAs), such as isobutyric acid, acetic acid, and propionic acid, were increased in saffron-treated mice. Our data suggest that pre-treatment with saffron inhibits DSS-induced pro-inflammatory cytokine secretion, modulates gut microbiota composition, prevents the depletion of SCFAs, and reduces the susceptibility to colitis.

Association of Patients' Perception of Quality of Healthcare Received and Colorectal Cancer Screening Uptake: An Analysis of 2 National Surveys in the USA.

OBJECTIVE: It is not known whether patients' ratings of the quality of healthcare services they receive truly correlate with the quality of care from their providers. Understanding this association can potentiate improvement in healthcare delivery. We evaluated the association between patients' ratings of the quality of healthcare services received and uptake of colorectal cancer (CRC) screening. SUBJECTS AND METHODS: We used 2 iterations of the Health Information National Trends Survey (HINTS) of adults in the USA. HINTS 2007 (4,007 respondents; weighted population = 75,397,128) evaluated whether respondents were up to date with CRC screening while HINTS 4 cycle 3 (1,562 respondents; weighted population = 76,628,000) evaluated whether participants had ever received CRC screening in the past. All included respondents from both surveys were at least 50 years of age, had no history of CRC, and had rated the quality of healthcare services that they had received at their healthcare provider's office in the previous 12 months. RESULTS: HINTS 2007 data showed that respondents who rated their healthcare as good or fair/poor were significantly less likely to be up to date with CRC screening compared to those who rated their healthcare as excellent. We found comparable results from analysis of HINTS 4 cycle 3 data with poorer uptake of CRC screening as the healthcare quality ratings of respondents reduced. CONCLUSION: Our study suggests that patients who reported receiving lower quality of healthcare services were less likely to have undergone and be compliant with CRC screening recommendations. It is important to pay close attention to patient feedback surveys in order to improve healthcare delivery.

Altered ARID1A expression in colorectal cancer.

BACKGROUND: ARID1A has been described as a tumor suppressor gene, participating in chromatin re-modeling, epithelial-mesenchymal-transition and many other cellular and molecular processes. It has been cited as a contribute in tumorigenesis. The role of ARID1A in CRC is not yet defined. AIM: To investigate the role of ARID1A methylation and CNV in its expression in CRC cell lines and to examine the relationship between ARID1A status with survival and clinicopathologic characteristics in patients with CRC. METHODS: We used RT-PCR to determine both CNV and expression of ARID1A from six CRC cell lines. We used MSP to evaluate methylation of ARID1A. IHC was used to assess ARID1A protein expression. We also evaluated MSI and EMAST status in 18 paired CRC and adjacent normal tissues. 5AzadC was used to assess effect of DNA demethylation on ARID1A expression. Statistical analysis was performed to establish correlations between ARID1A expression and other parameters. RESULTS: Among the 18 CRC tumors studied, 7 (38.8%) and 5 tumors (27.7%) showed no or low ARID1A expression, respectively. We observed no significant difference in ARID1A expression for overall patient survival, and no difference between clinicopathological parameters including MSI and EMAST. However, lymphatic invasion was more pronounced in the low/no ARID1A expression group when compared to moderate and high expression group (33% VS. 16.6% respectively. ARID1A promoter methylation was observed in 4/6 (66%) cell lines and correlated with ARID1A mRNA expression level ranging from very low in SW48, to more pronounced in HCT116 and HT-29/219. Treatment with the methyltransferase inhibitor 5-Azacytidine (5-aza) resulted in a 25.4-fold and 6.1-fold increase in ARID1A mRNA expression in SW48 and SW742 cells, respectively, while there was no change in SW480 and LS180 cells. No ARID1A CNV was observed in the CRC cell lines. CONCLUSION: ARID1A expression is downregulated in CRC tissues which correlates with it being a tumor suppressor protein. This finding confirms ARID1A loss of expression in CRC development. Our in-vitro results suggest high methylation status associates with reduced ARID1A expression and contributes to CRC tumorigenesis. However, there was no significant association between ARID1A loss of expression and clinicopathological characteristics. Future in-vivo analysis is warranted to further establish ARID1A role in colorectal neoplastic transformation.

Analysis of ß-catenin association with obesity in African Americans with premalignant and malignant colorectal lesions.

BACKGROUND: African Americans (AA) are at high risk for Colorectal Cancer (CRC). Studies report a 30-60% increase in CRC risk with physical inactivity, obesity and metabolic syndrome. Activation of the WNT/ß-catenin (CTNNB1) signaling pathway plays a critical role in colorectal carcinogenesis. Accumulating evidence also indicates a role of WNT-CTNNB1 signaling in obesity and metabolic diseases. AIM: To examine the association between obesity, ß-Catenin expression and colonic lesions in African Americans. METHODS: We reviewed the pathology records of 152 colorectal specimens from 2010 to 2012 (46 CRCs, 74 advanced adenomas and 32 normal colon tissues). Tissue Microarrays (TMA) were constructed from these samples. Immunohistochemistry (IHC) for CTNNB1 (ß-Catenin; clone ß-Catenin-1) was performed on the constructed TMAs. The IHC results were evaluated by 2 pathologists and the nuclear intensity staining was scored from 0 to 4. BMI, sex, age, location of the lesion and other demographic data were obtained. RESULTS: Positive nuclear staining in normal, advanced adenoma and CRC was 0, 24 and 41%, respectively (P < 0.001). CRC was asso ciated with positive status for nuclear CTNNB1 intensity (adjusted OR: 3.40, 95%CI = 1.42-8.15, P = 0.006 for positive nuclear staining) compared to non-CRC samples (Normal or advanced adenoma). Nuclear staining percentage has a fair diagnostic ability for CRC with an AUC of 0.63 (95%CI = 0.55-0.71). Overweight/obese patients (BMI > 25) did not show a significant difference in (p = 0.3) nuclear CTNNB1 staining (17% positive in normal weight vs. 27% positive in overweight/obese). The association between nuclear intensity and CRC was not different between normal and overweight patients (P for interaction = 0.6). The positive nuclear CTNNB1status in CRC stage III and IV (35% of all CRC) was not different from stage I and II (50% vs. 36%, respectively, P = 0.4). CONCLUSION: In our study, advanced adenoma and CRC were associated with activation of ß-catenin in physically fit, overweight and obese patients. Thus, obesity and WNT/ß-Catenin pathway seem to be independent in African American patients. WNT/ß-Catenin signaling pathway has a potential to be used as an effector in colon carcinogenic transformation. Whether or not BMI is a modifier of this pathway needs to be investigated further.

Inflammatory polyps occur more frequently in inflammatory bowel disease than other colitis patients.

BACKGROUND: Colitis is generally considered a risk factor for colon neoplasia. However, not all types of colitis seem to have equal neoplastic transformation potential. AIM: To determine the prevalence of colorectal polyps in a predominantly African American population with inflammatory bowel disease (IBD) and Non-IBD/Non-Infectious Colitis (NIC). METHODS: We retrospectively evaluated medical records of 1060 patients previously identified with colitis at Howard University Hospital, based on ICD-10 code. Among these, 485 patients were included in the study: 70 IBD and 415 NIC based on a thorough review of colonoscopy, pathology and clinical reports. Logistic regression analysis was applied to estimate the risk of polyps in patients with IBD compared to those with NIC after adjusting for age and sex. A subgroup analysis within the IBD group was performed. RESULTS: Of the 485 patients, 415 were NIC and 70 were IBD. Seventy-three percent of the NIC patients and 81% of the IBD patients were African Americans. Forty six percent of IBD and 41% of NIC cases were male. IBD patients were younger than NIC patients (median age of 38 years vs. 50, P < 0.001). The prevalence of all types of polyps was 15.7 and 8.2% in the IBD and NIC groups, respectively (P = 0.045). Among patients with polyps, the prevalence of inflammatory polyps was higher in the IBD group (55%) compared to the NIC group (12%). After adjusting for age, sex and race, odds ratio of inflammatory polyps in IBD patients was 6.0 (P = 0.016). Adenoma prevalence was 4.3% (3/70) in IBD patients and 3.9% (16/415) in the NIC patients (p = 0.75). The anatomic distribution of lesions and colitis shows that polyps occur predominantly in the colitis field regardless of colitis type. More polyps were present in the ulcerative colitis patients when compared to Crohn's disease patients (27% vs. 5%, P < 0.001) within the IBD group. CONCLUSION: Our study shows that inflammatory polyps are more common in IBD patients when compared to NIC patients. Most polyps were in the same location as the colitis.

Elevated Risk for Sessile Serrated Polyps in African Americans with Endometrial Polyps.

BACKGROUND: Colorectal and endometrial lesions increase with age. It is not known if these two precursor lesions in sporadic cases associate with each other. AIM: To determine the association between colorectal polyps and endometrial polyps (EP) in African Americans. METHODS: We reviewed records of patients referred to gynecology clinics and had colonoscopy at Howard University Hospital from January 2004 to December 2015. We defined cases as all patients who had EP and underwent colonoscopy. For controls, we used EP-free patients who underwent colonoscopy. Logistic regression analysis was used to assess the association between colon polyps and EP. RESULTS: The median age was 60 years in 118 Cases and 57 years in 664 Controls. The overall colorectal polyps prevalence in the two groups was not statistically different (54% in controls vs. 52% in cases, P = 0.60). Sessile serrated adenoma/polyps (SSPs) were more frequent in cases (8% vs. 2% in controls, P = 0.003). Sigmoid and rectal locations were more prevalent in controls than cases. In multivariate analysis and after adjusting for age, diabetes mellitus (DM), and BMI, SSPs were associated with EP occurrence with an odds ratio of 4.6 (CI 1.2-16.7, P = 0.022). CONCLUSION: Colorectal polyp prevalence was similar in EP patients compared to EP-free controls. However, we observed a significant association between higher-risk SSPs in patients with EP. The prevalence of smoking and DM was higher in these patients. Females with EP might benefit from a screening for colonic lesions in an age-independent manner.

Using Patients' Social Network to Improve Compliance to Outpatient Screening Colonoscopy Appointments Among Blacks: A Randomized Clinical Trial.

OBJECTIVES: Patient navigation improves colorectal cancer screening among underserved populations, but limited resources preclude widespread adoption in minority-serving institutions. We evaluated whether a patient's self-selected social contact person can effectively facilitate outpatient screening colonoscopy. METHODS: From September 2014 to March 2017 in an urban tertiary center, 399 black participants scheduled for outpatient screening colonoscopy self-selected a social contact person to be a facilitator and provided the person's phone number. Of these, 201 participants (50.4%) were randomly assigned to the intervention arm for their social contact persons to be engaged by phone. The study was explained to the social contact person with details about colonoscopy screening and bowel preparation process. The social contacts were asked to assist the participants, provide support, and encourage compliance with the procedures. The social contact person was not contacted in the usual care arm, n = 198 (49.6%). We evaluated attendance to the scheduled outpatient colonoscopy and adequacy of bowel preparation. Analysis was performed by intention to treat. RESULTS: The social contact person was reached and agreed to be involved for 130 of the 201 participants (64.7%). No differences were found in the proportion of participants who underwent screening colonoscopy (77.3% vs 77.2%; relative risk = 1.01; 95% confidence interval: 0.91-1.12), but there was a modest increase in the proportion with adequate bowel preparation with social contact involvement (89.1% vs 80.9%; relative risk = 1.10; 95% confidence interval: 1.00-1.21). DISCUSSION: Engaging a patient's social network to serve in the role of a patient navigator did not improve compliance to outpatient screening colonoscopy but modestly improved the adequacy of bowel preparation.

Can the rate and location of sessile serrated polyps be part of colorectal Cancer disparity in African Americans?

BACKGROUND: Up to 30% of colorectal cancers develop through the serrated pathway. African Americans (AAs) suffer a disproportionate burden of colorectal cancer. The aim of this study was to evaluate clinicopathological features of AA patients diagnosed with sessile serrated polyps (SSPs). METHODS: We conducted a retrospective study of all colonoscopies (n = 12,085) performed at Howard University Hospital, from January 1st, 2010 to December 31st, 2015, of which 83% were in AA patients, (n = 10,027). Among AAs, pathology reports confirmed 4070 patients with polyps including 252 with SSPs. Demographic and clinical variables (i.e. sex, age, BMI, anatomic location, clinical symptoms, polyp size, and clinical indications were collected at colonoscopy. RESULTS: In the AA population, the median age was 56 with interquartile range (IQR) of 51 to 62 years, 54% were female, and 48% had a BMI > 30. The most common reason for colonoscopy was screening (53%), whereas the prevalent reasons for diagnostic colonoscopies were changes in bowel habits (18%) and gastrointestinal bleeding (17%). The total number of SSPs among the 252 AA (diagnosed with SSPs) was 338. Of these, 9% (n = 29/338) had some degree of cytological dysplasia, primarily in the ascending colon (n = 6/42, 14%), Transverse colon (n = 2/16, 13%) and rectosigmoid (n = 19/233, 8%). About 24% of patients had more than 2 polyps. Most patients (76%) had distal SSPs (rectal and rectosigmoid), in comparison to 14% of proximal polyps and 10% of bilateral locations. Median SSA/P size for all locations was 0.6 cm. CONCLUSION: The prevalence of SSPs accounts for 6% of all polyps in AA patients and was diagnosed in 2.5% of all colonoscopies (n = 252/10,027), which is higher than Caucasians in the US. SSPs were predominantly located in the left side, as compared to published literature showing the predominance in the right side of the colon. Screening of CRC will have the chance to detect high risk SSA/P in this population.

Racial Disparity in Gastrointestinal Cancer Risk.

Cancer from the gastrointestinal tract and its associated excretory organs will occur in more than 300,000 Americans in 2017, with colorectal cancer responsible for >40% of that burden; there will be more than 150,000 deaths from this group of cancers in the same time period. Disparities among subgroups related to the incidence and mortality of these cancers exist. The epidemiology and risk factors associated with each cancer bear out differences for racial groups in the United States. Esophageal adenocarcinoma is more frequent in non-Hispanic whites, whereas esophageal squamous cell carcinoma with risk factors of tobacco and alcohol is more frequent among blacks. Liver cancer has been most frequent among Asian/Pacific Islanders, chiefly due to hepatitis B vertical transmission, but other racial groups show increasing rates due to hepatitis C and emergence of cirrhosis from non-alcoholic fatty liver disease. Gastric cancer incidence remains highest among Asian/Pacific Islanders likely due to gene-environment interaction. In addition to esophageal squamous cell carcinoma, cancers of the small bowel, pancreas, and colorectum show the highest rates among blacks, where the explanations for the disparity are not as obvious and are likely multifactorial, including socioeconomic and health care access, treatment, and prevention (vaccination and screening) differences, dietary and composition of the gut microbiome, as well as biologic and genetic influences. Cognizance of these disparities in gastrointestinal cancer risk, as well as approaches that apply precision medicine methods to populations with the increased risk, may reduce the observed disparities for digestive cancers.

GPNMB methylation: a new marker of potentially carcinogenic colon lesions.

BACKGROUND: Epigenetic plays an important role in colorectal neoplasia process. There is a need to determine sound biomarkers of colorectal cancer (CRC) progression with clinical and therapeutic implications. Therefore, we aimed to examine the role and methylation status of Glyco Protein Non-Metastatic GPNM B (GPNMB) gene in normal, adenoma and CRC in African American (AA) patients. METHODS: The methylation status of 13 CpG sites (chr7: 23287345-23,287,426) in GPNMB gene's promoter, was analyzed by pyrosequencing in human CRC cell lines (HCT116, SW480, and HT29) and microdissected African American paraffin embedded samples (20 normal, 21 non-advanced adenoma (NA), 48 advanced adenoma (AD), and 20 cancer tissues. GPNMB expression was analyzed by immunohistochemistry (IHC) on tissue microarrays (TMA). Correlations between GPNMB methylation and expression with clinicopathological features were analyzed. GPNMB functional analysis was performed in triplicates using cell proliferation, migration and invasion assays in HCT116 colon cell line after stable transfection with a GPNMB-cDNA expression vector. RESULTS: GPNMB methylation was lower in normal mucosa compared to CRC samples (1/20 [5%] vs. 18/20 [90%]; P < 0.001). AD also had a significantly higher GPNMB methylation frequency than normal colon samples (42/48 [88%] vs 1/20 [5%]; P < 0.001). GPNMB was more frequently methylated in AD than in matched normal mucosa from three patients (3/3 [100%] vs 1/3 [33.3%]; P < 0.001). The frequency of GPNMB methylation in NA differed significantly from that in the normal mucosa (16/21 [76%] vs 1/20 [5%]; P = 0.008). There was statistically significant correlation of higher methylation at advanced stages and lower methylation at stage 1 CRCs (P < 0.05). In agreement with these findings, GPNMB protein expression decreased in CRC tissues compared with AD and NA colon mucosa (p < 0.05). GPNMB overexpression in HCT116 colon cancer cell line decreased cell proliferation [(24 h, P = 0.02), (48 h, P < 0.001, 72 h, P = 0.007)], invasion (p < 0.05) and migration (p > 0.05) compared to the mock-transfected cells. CONCLUSION: Our data indicate a high methylation profile leading to a lower GPNMB expression in adenoma and CRC samples. The functional analysis established GPNMB as a potential tumor suppressor gene. As such, GPNMB might be useful as a biomarker of adenomas with high carcinogenic potential.