Effect of Real-Time Computer-Aided Polyp Detection System (ENDO-AID) on Adenoma Detection in Endoscopists-in-Training: A Randomized Trial.

BACKGROUND: The effect of computer-aided polyp detection (CADe) on adenoma detection rate (ADR) among endoscopists-in-training remains unknown. METHODS: We performed a single-blind, parallel-group, randomized controlled trial in Hong Kong between April 2021 and July 2022 (NCT04838951). Eligible subjects undergoing screening/surveillance/diagnostic colonoscopies were randomized 1:1 to receive colonoscopies with CADe (ENDO-AID[OIP-1]) or not (control) during withdrawal. Procedures were performed by endoscopists-in-training with <500 procedures and <3 years' experience. Randomization was stratified by patient age, sex, and endoscopist experience (beginner vs intermediate level, <200 vs 200-500 procedures). Image enhancement and distal attachment devices were disallowed. Subjects with incomplete colonoscopies or inadequate bowel preparation were excluded. Treatment allocation was blinded to outcome assessors. The primary outcome was ADR. Secondary outcomes were ADR for different adenoma sizes and locations, mean number of adenomas, and non-neoplastic resection rate. RESULTS: A total of 386 and 380 subjects were randomized to CADe and control groups, respectively. The overall ADR was significantly higher in the CADe group than in the control group (57.5% vs 44.5%; adjusted relative risk, 1.41; 95% CI, 1.17-1.72; P < .001). The ADRs for <5 mm (40.4% vs 25.0%) and 5- to 10-mm adenomas (36.8% vs 29.2%) were higher in the CADe group. The ADRs were higher in the CADe group in both the right colon (42.0% vs 30.8%) and left colon (34.5% vs 27.6%), but there was no significant difference in advanced ADR. The ADRs were higher in the CADe group among beginner (60.0% vs 41.9%) and intermediate-level (56.5% vs 45.5%) endoscopists. Mean number of adenomas (1.48 vs 0.86) and non-neoplastic resection rate (52.1% vs 35.0%) were higher in the CADe group. CONCLUSIONS: Among endoscopists-in-training, the use of CADe during colonoscopies was associated with increased overall ADR. (ClinicalTrials.gov, Number: NCT04838951).

Identification of Tissue Types and Gene Mutations From Histopathology Images for Advancing Colorectal Cancer Biology.

Objective: Colorectal cancer (CRC) patients respond differently to treatments and are sub-classified by different approaches. We evaluated a deep learning model, which adopted endoscopic knowledge learnt from AI-doscopist, to characterise CRC patients by histopathological features. Results: Data of 461 patients were collected from TCGA-COAD database. The proposed framework was able to 1) differentiate tumour from normal tissues with an Area Under Receiver Operating Characteristic curve (AUROC) of 0.97; 2) identify certain gene mutations (MYH9, TP53) with an AUROC > 0.75; 3) classify CMS2 and CMS4 better than the other subtypes; and 4) demonstrate the generalizability of predicting KRAS mutants in an external cohort. Conclusions: Artificial intelligent can be used for on-site patient classification. Although KRAS mutants were commonly associated with therapeutic resistance and poor prognosis, subjects with predicted KRAS mutants in this study have a higher survival rate in 30 months after diagnoses.

Third Asia-Pacific consensus recommendations on colorectal cancer screening and postpolypectomy surveillance.

The Asia-Pacific region has the largest number of cases of colorectal cancer (CRC) and one of the highest levels of mortality due to this condition in the world. Since the publishing of two consensus recommendations in 2008 and 2015, significant advancements have been made in our knowledge of epidemiology, pathology and the natural history of the adenoma-carcinoma progression. Based on the most updated epidemiological and clinical studies in this region, considering literature from international studies, and adopting the modified Delphi process, the Asia-Pacific Working Group on Colorectal Cancer Screening has updated and revised their recommendations on (1) screening methods and preferred strategies; (2) age for starting and terminating screening for CRC; (3) screening for individuals with a family history of CRC or advanced adenoma; (4) surveillance for those with adenomas; (5) screening and surveillance for sessile serrated lesions and (6) quality assurance of screening programmes. Thirteen countries/regions in the Asia-Pacific region were represented in this exercise. International advisors from North America and Europe were invited to participate.

Joint effect between bisphenol A and alcohol consumption on benign prostatic hyperplasia: A case-control study in Hong Kong Chinese males.

BACKGROUND: Whether bisphenol A (BPA) exposure is a contributing factor to benign prostatic hyperplasia (BPH) remains unclear. This study evaluated the association between chronic BPA exposure and BPH risk, and explored whether this association was modified by alcohol drinking. METHODS: This study included a total of 650 BPH cases and 650 controls recruited from the same hospital in Hong Kong during 2011-2016. Chronic BPA exposure level was estimated by a validated cumulative BPA exposure index (CBPAI). We performed unconditional logistic regression model to examine the association of BPH risk with potential sources of BPA exposure via oral intake and CBPAI. We further tested the interactions between CBPAI and alcohol consumption habits on BPH risk. RESULTS: A positive exposure-response relationship was observed between CBPAI and BPH risk. Frequent BPA exposure via oral intake of foods heated in a plastic box/bag (odds ratio [OR] = 3.52, 95% confidence interval [CI]: 1.51-8.22), cooling water in a plastic bottle (OR = 2.65, 95% CI: 1.33-5.27), or using a plastic cup to contain hot water (OR = 4.14, 95% CI: 1.02-16.89), was significantly associated with increased BPH risk. Compared with nonalcohol drinkers, alcohol drinkers was insignificantly associated with BPH risk (OR = 1.10, 95% CI: 0.77-1.57), but it demonstrated a more remarkable positive gradient between CBPAI exposure and BPH risk among alcohol drinkers, indicating an additive interaction between CBPAI and alcohol on BPH risk (synergy index = 4.24, 95% CI: 1.21-14.94). CONCLUSIONS: Chronic oral BPA exposure increased BPH risk with a positive exposure-response relationship among Hong Kong Chinese, and alcohol drinking amplified the effect of BPA on BPH. Hence, minimizations of containing food or water/beverage in plastic containers and drinking alcohol are recommended in the community to mitigate BPH risk. Future larger and designated studies are warranted.

Comparison between robotic natural orifice specimen extraction surgery and traditional laparoscopic low anterior resection for middle and low rectal cancer: A propensity score matching analysis.

BACKGROUND AND OBJECTIVES: This study aimed to find the advantages of robotic natural orifice specimen extraction surgery (NOSES) for middle and low rectal cancer, compared with traditional laparoscopic low anterior resection (LAR). METHODS: Patients receiving robotic NOSES or traditional laparoscopic LAR were retrospectively enrolled from 2013-10 to 2019-06, with middle and low rectal cancer, maximum diameter ≤ 5 cm, pT1-3 or ypT1-3 stage, no distant metastases. The baseline of the two groups was balanced using the propensity score matching method. Surgical quality, postoperative recovery, and long-term oncological outcomes were compared. RESULTS: Totally 137 eligible patients with robotic NOSES and 137 matched patients with traditional laparoscopic LAR were enrolled. Robotic NOSES had a significantly lower open conversion rate (0 vs. 4.4%, p = .030), less intraoperative hemorrhage (50 ml vs. 80 ml, p < .001) and longer distance from distal resection margin of low rectal cancer (1.5 cm vs. 1.0 cm, p = .030). Robotic NOSES significantly reduced the 30-day postoperative complication rate of Clavien-Dindo grade II or higher (17.5% vs. 31.4%, p = .008), promoted gastrointestinal and urinary function recovery, reduced postoperative pain and hospital stay (6.0 vs. 7.0 d, p = .022). The two groups were similar in long-term survival. CONCLUSIONS: Compared with traditional laparoscopic LAR, robotic NOSES had significant advantages in improving surgical quality and promoting postoperative recovery.

Effectiveness of One-Stop Screening for Colorectal, Breast, and Prostate Cancers: A Population-Based Feasibility Study.

Colorectal cancer (CRC), prostate cancer (PC) and breast cancer (BC) are among the most common cancers worldwide with well-established screening strategies. We aim to investigate the effectiveness and compliance of a one-stop screening service for CRC, PC and BC. Asymptomatic subjects aged 50-75 years were invited. Eligible subjects were offered fecal immunochemical test (FIT) for CRC screening. Serum prostate specific antigen (PSA) and Prostate Health Index (PHI) were offered for male PC screening and mammogram (MMG) for female BC screening as a one-stop service. Colonoscopy was offered to FIT+ subjects, prostate biopsy to PSA/PHI+ (PSA>10/PHI≥35) males and breast biopsy to MMG+ (Breast Imaging-Reporting and Data System, BI-RADS≥4) females. From August 2018 to April 2020, 3165 subjects were recruited. All participants (1372 men and 1793 women) were willing to accept FIT for CRC screening, and PSA/PHI test or MMG as second cancer screening. 102 subjects diagnosed advanced neoplasms after colonoscopy. Thirty-three males diagnosed PC after prostate biopsy and 15 females diagnosed BC after breast biopsy. No major complication reported in first tier screening tests. Subjects who were willing to undergo CRC screening were highly likely to accept other cancer screening when offered in a one-stop program. In conclusion, the effectiveness and compliance of a one-stop service for CRC, PC, and BC screening among asymptomatic subjects were high. Future studies should be conducted to test various ways of integrating cancer screening programs. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT04034953.

The role of metacognition and its indirect effect through cognitive attentional syndrome on fear of cancer recurrence trajectories: A longitudinal study.

OBJECTIVE: This longitudinal study mapped distinct trajectories of fear of cancer recurrence (FCR) over 12 months among patients with breast (BC) or colorectal (CRC) cancer, and examined if metacognition, indirectly via attentional bias, intrusive thoughts and avoidance (hallmarks of cognitive attentional syndrome; CAS) predicted FCR trajectory membership. METHODS: Two hundred and seventy BC (n = 163) or CRC (n = 107) patients were assessed at 8-weeks, 3-, 6-, and 12-months postsurgery on a measure of FCR (FCRI-SF). Metacognition (MCQ-30), Intrusive and Avoidant Thoughts (CIES-R) and attentional bias (dot-probe tasks) were assessed at baseline. Latent growth mixture modeling identified FCR trajectories. Fully-adjusted Multinomial Logistic Regression identified whether direct and indirect effects of metacognition through CAS determined FCR trajectory membership. RESULTS: Three distinct FCR trajectories were identified, namely, low-stable (62.4%), high-stable (29.2%), and recovery (8.3%). Negative beliefs about worry, cognitive confidence, and age predicted FCR trajectories (χ2 (6) = 38.31, P<.001). Compared with Low-stable group, Recovery FCR patients held greater Negative beliefs about worry (OR = 1.13, P = .035) and High-stable FCR patients reported poorer Cognitive confidence (OR = 1.12, P = .004). The effect of Negative beliefs about worry was partially mediated by avoidance (ß = .06, 95% CIs 0.03-0.12) and fully mediated by intrusive thoughts (ß = .14, 95% CIs 0.08-0.20). Attentional bias did not predict FCR trajectories. CONCLUSIONS: While most patients experienced low level of FCR, 3 in 10 persistently worried about cancer returning over the first 12-months postsurgery. Modifying metacognitive knowledge to interrupt maladaptive cognitive processing including intrusion and avoidance may be an effective therapeutic intervention for patients at risk of persistent FCR.

Eukaryotic elongation factor-2 kinase expression is an independent prognostic factor in colorectal cancer.

BACKGROUND: Prognostication of patients with colorectal cancer (CRC) currently relies on tumor-node-metastasis (TNM) staging but clinical outcomes of patients of the same histoclinical stage are heterogeneous. It is therefore imperative to devise novel molecular tests to stratify CRC patients. Our previous work demonstrated that eukaryotic elongation factor-2 kinase (EEF2K) is a tumor suppressor in CRC. Herein, we investigated EEF2K expression in CRC and determined its relationship with clinicopathological parameters. METHODS: Quantitative RT-PCR and Westerns blots were used to examine EEF2K expression in primary tumor and the adjacent non-tumor tissues of CRC patients (n = 20). Kaplan-Meier curves and Cox regression analysis were used to assess the association between clinical outcomes of CRC patients and EEF2K protein expression determined by immunohistochemistry on tissue microarray (n = 151). RESULTS: EEF2K was significantly downregulated at both mRNA and protein levels in tumors of CRC patients. Univariate Cox regression analysis revealed that CRC patients with high tumor grade, advanced TNM staging and low EEF2K expression were associated with worse overall survival. Multivariate analysis further demonstrated that low EEF2K expression was an independent factor for predicting poorer overall survival in CRC patients (p = 0.014; Hazard ratio = 2.951; 95% confidence interval: 1.240-7.024). The 5-year survival rate was 82.8% in the EEF2K-high-expression group versus 63.9% in the EEF2K-low-expression group (p = 0.0118). The association of overall survival with EEF2K expression in CRC patients was verified in The Cancer Genome Atlas (TCGA) cohort. CONCLUSIONS: EEF2K is downregulated in CRC and its expression can be employed as a prognostic marker for CRC patients independent of TNM staging.

Prospective clinical trial to evaluate safety and feasibility of using a single port flexible robotic system for transoral head and neck surgery.

INTRODUCTION: The aim of this study was to determine the clinical safety and feasibility of a novel single-port flexible robot for Transoral Robotic Surgery (TORS). MATERIALS AND METHODS: This was a prospective phase II / IDEAL stage 2 clinical trial of both benign and malignant lesions of the head and neck. The primary endpoint included conversion rates and perioperative complications within 30 days following surgery. The study was registered on www.ClinicalTrials.gov (NCT03010813). The Fisher's exact test and Mann-Whitney U test were used to compare categorical, and non-parametric data for the trial. A p value <0.05 was considered to be statistically significant. Statistical analysis was performed with SPSS 20.0 (IBM Corp., Armonk, New York) RESULTS: Twenty-one patients safely underwent TORS with the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA) demonstrating the feasibility of access to the nasopharynx, oropharynx, larynx and hypopharynx. There were no conversions of the robotic surgical system. There were no serious adverse events or adverse events related to the use of the robot at 30-day follow-up for all patients. CONCLUSIONS: In a prospective Phase II clinical trial, a novel single-port flexible robotic system appears safe and feasible to use for transoral endoscopic head and neck surgery to access the nasopharynx, oropharynx, larynx and hypopharynx.

Activation of PTEN by inhibition of TRPV4 suppresses colon cancer development.

Transient receptor potential vanilloid type 4 (TRPV4) is a Ca2+-permeable cation channel that is known to be an osmosensor and thermosensor. Currently, limited evidence shows that TRPV4 plays opposite roles in either promoting or inhibiting cancer development in different cancer types. Furthermore, the precise biological functions and the underlying mechanisms of TRPV4 in carcinogenesis are still poorly understood. In this study, we demonstrated that TRPV4 is upregulated in colon cancer and associated with poor prognosis. Contrary to the reported cell death-promoting activity of TRPV4 in certain cancer cells, TRPV4 positively regulates cell survival in human colon cancer in vitro and in vivo. Inhibition of TRPV4 affects the cell cycle progression from the G1 to S phase through modulating the protein expression of D-type cyclins. Apoptosis and autophagy induced by TRPV4 silencing attenuate cell survival and potentiate the anticancer efficacy of chemotherapeutics against colon cancer cells. In addition, PTEN is activated by inhibition of TRPV4 as indicated by the dephosphorylation and increased nuclear localization. Knockdown of PTEN significantly abrogates TRPV4 silencing induced growth inhibition and recovers the capability of clonogenicity, as well as reduced apoptosis in colon cancer cells. Thus, PTEN regulates the antigrowth effects induced by TRPV4 inhibition through both phosphatase-dependent and independent mechanisms. In conclusion, inhibition of TRPV4 suppresses colon cancer development via activation of PTEN pathway. This finding suggests that downregulation of TPRV4 expression or activity would conceivably constitute a novel approach for the treatment of human colon cancer.

Orientation-aware plasma cell-free DNA fragmentation analysis in open chromatin regions informs tissue of origin.

Cell-free DNA (cfDNA) in human plasma is a class of biomarkers with many current and potential future diagnostic applications. Recent studies have shown that cfDNA molecules are not randomly fragmented and possess information related to their tissues of origin. Pathologies causing death of cells from particular tissues result in perturbations in the relative distribution of DNA from the affected tissues. Such tissue-of-origin analysis is particularly useful in the development of liquid biopsies for cancer. It is therefore of value to accurately determine the relative contributions of the tissues to the plasma DNA pool in a simultaneous manner. In this work, we report that in open chromatin regions, cfDNA molecules show characteristic fragmentation patterns reflected by sequencing coverage imbalance and differentially phased fragment end signals. The latter refers to differences in the read densities of sequences corresponding to the orientation of the upstream and downstream ends of cfDNA molecules in relation to the reference genome. Such cfDNA fragmentation patterns preferentially occur in tissue-specific open chromatin regions where the corresponding tissues contributed DNA into the plasma. Quantitative analyses of such signals allow measurement of the relative contributions of various tissues toward the plasma DNA pool. These findings were validated by plasma DNA sequencing data obtained from pregnant women, organ transplantation recipients, and cancer patients. Orientation-aware plasma DNA fragmentation analysis therefore has potential diagnostic applications in noninvasive prenatal testing, organ transplantation monitoring, and cancer liquid biopsy.

Transcervical minimally invasive esophagectomy using da Vinci® SP™ Surgical System: a feasibility study in cadaveric model.

BACKGROUND: This is a preclinical cadaveric study to investigate the feasibility of transcervical esophagectomy using a novel single-port robotic surgical system. METHODS: A 40-mm cervical incision was created over left supraclavicular fossa. The novel da Vinci® SP™ Surgical System was introduced through a wound retraction port. The mobilization of esophagus was performed using da Vinci SP from cervical, thoracic to abdominal segments. Lymph nodes were dissected en bloc with esophagus. RESULTS: The transcervical esophagectomy with complete mobilization of the cervical, thoracic, and abdominal esophagus was completed in 60 min. The procedure was completed using the novel da Vinci SP Surgical System, which was introduced via the cranial side over the left cervical incision. No additional port was used for retraction and dissection, and the esophageal hiatus could be reached after complete transcervical dissection. CONCLUSION: This preclinical study demonstrated that transcervical esophagectomy is technically feasible and can be completed with the novel da Vinci SP Surgical System without additional ports or assistance. This will serve as an important step to the performance of robotic transcervical esophagectomy without the necessity of one-lung ventilation.

Liver- and Colon-Specific DNA Methylation Markers in Plasma for Investigation of Colorectal Cancers with or without Liver Metastases.

BACKGROUND: Measurement of DNA derived from different tissues in the circulating DNA pool can provide important information regarding the presence of many pathological conditions. However, existing methods involving genome-wide bisulfite sequencing are relatively expensive and may present challenges for large-scale analysis. METHODS: Through identifying differentially methylated regions in the liver and colon compared with other tissues, we identified 2 markers and developed corresponding droplet digital PCR assays. Plasma concentrations of liver-derived and colon-derived DNA were measured for 13 liver transplant recipients, 40 liver cancer patients, and 62 colorectal cancer (CRC) patients (27 with and 35 without liver metastases). RESULTS: In liver transplant recipients, the fractional concentration of liver-derived DNA measured using the liver-specific methylation marker and donor-specific alleles showed good correlation (Pearson R = 0.99). In liver cancer patients, the concentration of liver-derived DNA correlated positively with the maximal dimension of the tumor (Spearman R = 0.74). In CRC patients with and without liver metastasis, the plasma concentrations of colon-derived DNA (median, 138 copies/mL and 4 copies/mL, respectively) were increased compared with the 30 healthy controls (26 had undetectable concentrations). The absolute concentration of liver-derived DNA provided a better differentiation between CRC patients with and without liver metastasis compared with the fractional concentration (area under ROC curve, 0.85 vs 0.75). CONCLUSIONS: Quantitative analysis of plasma DNA with tissue-specific methylation patterns using droplet digital PCR is applicable for the investigation of cancers and assessing organ transplantation. This approach is useful for differentiating patients with and without metastases to other organs.

Forkhead Box F2 Suppresses Gastric Cancer through a Novel FOXF2-IRF2BPL-ß-Catenin Signaling Axis.

DNA methylation has been identified as a hallmark of gastric cancer (GC). Identifying genes that are repressed by DNA promoter methylation is essential in providing insights into the molecular pathogenesis of gastric cancer. Using genome-wide methylation studies, we identified that transcription factor forkhead box F2 (FOXF2) was preferentially methylated in gastric cancer. We then investigated the functional significance and clinical implication of FOXF2 in gastric cancer. FOXF2 was silenced in gastric cancer cell lines and cancer tissues by promoter methylation, which was negatively associated with mRNA expression. Ectopic expression of FOXF2 inhibited proliferation, colony formation, G1-S cell-cycle transition, induced apoptosis of gastric cancer cell lines, and suppressed growth of xenograft tumors in nude mice; knockdown of FOXF2 elicited opposing effects. FOXF2 inhibited Wnt signaling by inducing ß-catenin protein ubiquitination and degradation independently of GSK-3ß. FOXF2 directly bound the promoter of E3 ligase interferon regulatory factor 2-binding protein-like (IRF2BPL) and induced its transcriptional expression. IRF2BPL in turn interacted with ß-catenin, increasing its ubiquitination and degradation. Multivariate Cox regression analysis identified FOXF2 hypermethylation as an independent prognostic factor of poor survival in early-stage gastric cancer patients. In conclusion, FOXF2 is a critical tumor suppressor in gastric carcinogenesis whose methylation status serves as an independent prognostic factor for gastric cancer patients.Significance: FOXF2-mediated upregulation of the E3 ligase IRF2BPL drives ubiquitylation and degradation of ß-catenin in gastric cancer, blunting Wnt signaling and suppressing carcinogenesis. Cancer Res; 78(7); 1643-56. ©2018 AACR.

Early results of a safety and feasibility clinical trial of a novel single-port flexible robot for transoral robotic surgery.

The aim of this study was to describe the early results of a phase 1 safety and feasibility clinical trial of the first clinical use of a novel robot for transoral robotic surgery (TORS)-the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA). Study design of this study is prospective clinical trial. The methods used in this study are prospective innovation, development, exploration, assessment, and long-term study phase 1 clinical trial. Early results of six patients underwent TORS with the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) demonstrate access the nasopharynx, oropharynx, larynx, and hypopharynx. There were no conversions of the robotic surgical system. There were no serious adverse events or adverse events related to the use of the robot at 30-day follow-up for all six patients. The early results of this safety and feasibility trial of the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) clearly demonstrate that the device is safe and that it is feasible in performing TORS to access the nasopharynx, oropharynx, larynx, and hypopharynx.

A novel miR-203-DNMT3b-ABCG2 regulatory pathway predisposing colorectal cancer development.

Colorectal cancer (CRC) is a major cause of mortality and morbidity worldwide. The majority of studies to date focused on genetic mutations and epigenetic changes that drive the CRC carcinogenesis process. Xenobiotic transporters play an important role in safeguarding our body from external toxic substances. These transporters lining the gastrointestinal tract protect us from dietary carcinogens. This study aimed to investigate the downregulation of an efflux transporter ABCG2 in CRC versus normal colon mucosa, so as to shed light on its relevance to CRC initiation and progression. We found that ABCG2 expression is at least 50-fold lower in adenomatous polyps and colon carcinoma specimens obtained from CRC patients than in their matched pair of adjacent normal colon mucosa. The underlying mechanism(s) for ABCG2 under-expression in CRC is currently not known. To this end, aberrant promoter methylation of ABCG2 has been reported to cause its repression in a few cancer types including renal carcinoma and multiple myeloma. In this study, miR-203 was found to be downregulated in all polyps and CRC specimens, relative to adjacent normal colon mucosa. We demonstrated that the de novo DNA methyltransferase DNMT3b is a direct target of miR-203. Importantly, by relieving the repression on DNMT3b, the lower expression of miR-203 in CRC caused ABCG2 promoter methylation and remarkable lower ABCG2 expression in colon cancer cell lines and the patient CRC specimens. The restoration of ABCG2 function via modulating this new microRNA-methylation mechanism in precancerous cells may represent an attractive strategy to delay the carcinogenesis process. © 2016 Wiley Periodicals, Inc.

Quantitation of faecal Fusobacterium improves faecal immunochemical test in detecting advanced colorectal neoplasia.

OBJECTIVE: There is a need for an improved biomarker for colorectal cancer (CRC) and advanced adenoma. We evaluated faecal microbial markers for clinical use in detecting CRC and advanced adenoma. DESIGN: We measured relative abundance of Fusobacterium nucleatum (Fn), Peptostreptococcus anaerobius (Pa) and Parvimonas micra (Pm) by quantitative PCR in 309 subjects, including 104 patients with CRC, 103 patients with advanced adenoma and 102 controls. We evaluated the diagnostic performance of these biomarkers with respect to faecal immunochemical test (FIT), and validated the results in an independent cohort of 181 subjects. RESULTS: The abundance was higher for all three individual markers in patients with CRC than controls (p<0.001), and for marker Fn in patients with advanced adenoma than controls (p=0.022). The marker Fn, when combined with FIT, showed superior sensitivity (92.3% vs 73.1%, p<0.001) and area under the receiver-operating characteristic curve (AUC) (0.95 vs 0.86, p<0.001) than stand-alone FIT in detecting CRC in the same patient cohort. This combined test also increased the sensitivity (38.6% vs 15.5%, p<0.001) and AUC (0.65 vs 0.57, p=0.007) for detecting advanced adenoma. The performance gain for both CRC and advanced adenoma was confirmed in the validation cohort (p=0.0014 and p=0.031, respectively). CONCLUSIONS: This study identified marker Fn as a valuable marker to improve diagnostic performance of FIT, providing a complementary role to detect lesions missed by FIT alone. This simple approach may improve the clinical utility of the current FIT, and takes one step further towards a non-invasive, potentially more accurate and affordable diagnosis of advanced colorectal neoplasia.

SLC25A22 Promotes Proliferation and Survival of Colorectal Cancer Cells With KRAS Mutations and Xenograft Tumor Progression in Mice via Intracellular Synthesis of Aspartate.

BACKGROUND & AIMS: Many colorectal cancer (CRC) cells contain mutations in KRAS. Analyses of CRC cells with mutations in APC or CTNNB1 and KRAS identified SLC25A22, which encodes mitochondrial glutamate transporter, as a synthetic lethal gene. We investigated the functions of SLC25A22 in CRC cells with mutations in KRAS. METHODS: We measured levels of SLC25A22 messenger RNA and protein in paired tumor and nontumor colon tissues collected from 130 patients in Hong Kong and 17 patients in China and compared protein levels with patient survival times. Expression of SLC25A22 was knocked down in KRAS mutant CRC cell lines (DLD1, HCT116, LOVO, SW480, SW620, and SW1116) and CRC cell lines without mutations in KRAS (CACO-2, COLO205, HT29, and SW48); cells were analyzed for colony formation, proliferation, glutaminolysis and aspartate synthesis, and apoptosis in Matrigel and polymerase chain reaction array analyses. DLD1 and HCT116 cells with SLC25A22 knockdown were grown as xenograft tumors in nude mice; tumor growth and metastasis were measured. SLC25A22 was expressed ectopically in HCT116 cells, which were analyzed in vitro and grown as xenograft tumors in nude mice. RESULTS: Levels of SLC25A22 messenger RNA and protein were increased in colorectal tumor tissues compared with matched nontumor colon tissues; increased protein levels were associated with shorter survival times of patients (P = .01). Knockdown of SLC25A22 in KRAS mutant CRC cells reduced their proliferation, migration, and invasion in vitro, and tumor formation and metastasis in mice, compared with cells without SLC25A22 knockdown. Knockdown of SLC25A22 reduced aspartate biosynthesis, leading to apoptosis, decreased cell proliferation in KRAS mutant CRC cells. Incubation of KRAS mutant CRC cells with knockdown of SLC25A22 with aspartate increased proliferation and reduced apoptosis, which required GOT1, indicating that oxaloacetate is required for cell survival. Decreased levels of oxaloacetate in cells with knockdown of SLC25A22 reduced regeneration of oxidized nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate. Reduced oxidized nicotinamide adenine dinucleotide inhibited glycolysis and decreased levels of adenosine triphosphate, which inactivated mitogen-activated protein kinase kinase and extracellular signal-regulated kinase signaling via activation of AMP-activated protein kinase. An increased ratio of oxidized nicotinamide adenine dinucleotide phosphate to reduced nicotinamide adenine dinucleotide phosphate induced oxidative stress and glutathione oxidation, which suppressed cell proliferation. Asparagine synthetase mediated synthesis of asparagine from aspartate to promote cell migration. CONCLUSIONS: SLC25A22 promotes proliferation and migration of CRC cells with mutations KRAS, and formation and metastasis of CRC xenograft tumors in mice. Patients with colorectal tumors that express increased levels of SLC25A22 have shorter survival times than patients whose tumors have lower levels. SLC25A22 induces intracellular synthesis of aspartate, activation of mitogen-activated protein kinase kinase and extracellular signal-regulated kinase signaling and reduces oxidative stress.

Colorectal Cancer Screening Based on Age and Gender: A Cost-Effectiveness Analysis.

We evaluated whether age- and gender-based colorectal cancer screening is cost-effective.Recent studies in the United States identified age and gender as 2 important variables predicting advanced proximal neoplasia, and that women aged <60 to 70 years were more suited for sigmoidoscopy screening due to their low risk of proximal neoplasia. Yet, quantitative assessment of the incremental benefits, risks, and cost remains to be performed.Primary care screening practice (2008-2015).A Markov modeling was constructed using data from a screening cohort. The following strategies were compared according to the Incremental Cost Effectiveness Ratio (ICER) for 1 life-year saved: flexible sigmoidoscopy (FS) 5 yearly; colonoscopy 10 yearly; FS for each woman at 50- and 55-year old followed by colonoscopy at 60- and 70-year old; FS for each woman at 50-, 55-, 60-, and 65-year old followed by colonoscopy at 70-year old; FS for each woman at 50-, 55-, 60-, 65-, and 70-year old. All male subjects received colonoscopy at 50-, 60-, and 70-year old under strategies 3 to 5.From a hypothetical population of 100,000 asymptomatic subjects, strategy 2 could save the largest number of life-years (4226 vs 2268 to 3841 by other strategies). When compared with no screening, strategy 5 had the lowest ICER (US$42,515), followed by strategy 3 (US$43,517), strategy 2 (US$43,739), strategy 4 (US$47,710), and strategy 1 (US$56,510). Strategy 2 leads to the highest number of bleeding and perforations, and required a prohibitive number of colonoscopy procedures. Strategy 5 remains the most cost-effective when assessed with a wide range of deterministic sensitivity analyses around the base case.From the cost effectiveness analysis, FS for women and colonoscopy for men represent an economically favorable screening strategy. These findings could inform physicians and policy-makers in triaging eligible subjects for risk-based screening, especially in countries with limited colonoscopic resources. Future research should study the acceptability, feasibility, and feasibility of this risk-based strategy in different populations.

Validation of a risk prediction score for proximal neoplasia in colorectal cancer screening: a prospective colonoscopy study.

This study developed a clinical scoring system to predict the risks of PN among screening participants for colorectal cancer. We recruited 5,789 Chinese asymptomatic screening participants who received colonoscopy in Hong Kong (2008-2014). From random sampling of 2,000 participants, the independent risk factors were evaluated for PN using binary regression analysis. The odds ratios for significant risk factors were used to develop a scoring system, with scores stratified into 'average risk' (AR):0-2 and 'high risk' (HR):3-5. The other 3,789 subjects formed an independent validation cohort. Each participant received a score calculated based on their risk factors. The performance of the scoring system was evaluated. The proportion of PN in the derivation and validation cohorts was 12.6% and 12.9%, respectively. Based on age, gender, family history, body mass index and self-reported ischaemic heart disease, 85.0% and 15.0% in the validation cohort were classified as AR and HR, respectively. Their prevalence of PN was 12.0% and 18.1%, respectively. Participants in the HR group had 1.51-fold (95% CI = 1.24-1.84, p < 0.001) higher risk of PN than the AR group. The overall c-statistics of the prediction model was 0.71(0.02). The scoring system is useful in predicting the risk of PN to prioritize patients for colonoscopy.