Multiplexed monitoring of a novel autoantibody diagnostic signature of colorectal cancer using HaloTag technology-based electrochemical immunosensing platform.

Background and Purpose: The humoral immune response in cancer patients can be used for early detection of the disease. Autoantibodies raised against tumor-associated antigens (TAAs) are promising clinical biomarkers for reliable cancer diagnosis, prognosis, and therapy monitoring. In this study, an electrochemical disposable multiplexed immunosensing platform able to integrate difficult- and easy-to-express colorectal cancer (CRC) TAAs is reported for the sensitive determination of eight CRC-specific autoantibodies. Methods: The electrochemical immunosensing approach involves the use of magnetic microcarriers (MBs) as solid supports modified with covalently immobilized HaloTag fusion proteins for the selective capture of specific autoantibodies. After magnetic capture of the modified MBs onto screen-printed carbon working electrodes, the amperometric responses measured using the hydroquinone (HQ)/H2O2 system were related to the levels of autoantibodies in plasma. Results: The biosensing platform was applied to the analysis of autoantibodies against 8 TAAs described for the first time in this work in plasma samples from healthy asymptomatic individuals (n=3), and patients with high-risk of developing CRC (n=3), and from patients already diagnosed with colorectal (n=3), lung (n=2) or breast (n=2) cancer. The developed bioplatform demonstrated an improved discrimination between CRC patients and controls (asymptomatic healthy individuals and breast and lung cancer patients) compared to an ELISA-like luminescence test. Conclusions: The proposed methodology uses a just-in-time produced protein in a simpler protocol, with low sample volume, and involves cost-effective instrumentation, which could be used in a high-throughput manner for reliable population screening to facilitate the detection of early CRC patients at affordable cost.

Identification of tumor-associated antigens with diagnostic ability of colorectal cancer by in-depth immunomic and seroproteomic analysis.

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer related death worldwide. Its diagnosis at early stages would significantly improve the survival of CRC patients. The humoral immune response has been demonstrated useful for cancer diagnosis, predating clinical symptoms up to 3 years. Here, we employed an in-depth seroproteomic approach to identify proteins that elicit a humoral immune response in CRC patients. The seroproteomic approach relied on the immunoprecipitation with patient-derived autoantibodies of proteins from CRC cell lines with different metastatic properties followed by LC-MS/MS. After bioinformatics, we focused on 31 targets of CRC autoantibodies. After WB and IHC validation, ERP44 and TALDO1 showed potential to discriminate disease-free and metastatic CRC patients, and time to recurrence of CRC patients in stage II. Using plasma samples of 30 healthy individuals, 28 premalignant individuals, and 32 CRC patients, nine out of 13 selected targets for seroreactive analysis showed significant diagnostic ability to discriminate either CRC patients or premalignant subjects from controls. Our results suggest that the here defined panel of CRC autoantibodies and their target proteins should be included in CRC blood-based biomarker panels to get a clinically useful blood-based diagnostic signature for CRC detection. SIGNIFICANCE: Colorectal cancer is one of the deadliest cancer types mainly due to its late diagnosis. Its early diagnosis, therefore, is of great importance since it would significantly improve the survival of CRC patients. In our work, the in-depth seroproteomic analysis of colorectal cancer using isolated IgGs from colorectal cancer patients and controls and protein extract of colorectal cancer cells provide the identification of valuable biomarkers with diagnostic and prognostic ability of the disease.

The specific seroreactivity to ∆Np73 isoforms shows higher diagnostic ability in colorectal cancer patients than the canonical p73 protein.

The p53-family is tightly regulated at transcriptional level. Due to alternative splicing, up to 40 different theoretical proteoforms have been described for p73 and at least 20 and 10 for p53 and p63, respectively. However, only the canonical proteins have been evaluated as autoantibody targets in cancer patients for diagnosis. In this study, we have cloned and expressed in vitro the most upregulated proteoforms of p73, ΔNp73α and ΔNp73ß, for the analysis of their seroreactivity by a developed luminescence based immunoassay test using 145 individual plasma from colorectal cancer, premalignant individuals and healthy controls. ∆Np73α seroreactivity showed the highest diagnostic ability to discriminate between groups. The combination of ∆Np73α, ∆Np73ß and p73 proteoforms seroreactivity were able to improve their individual diagnostic ability. Competitive inhibition experiments further demonstrated the presence of unique specific epitopes in ΔNp73 isoforms not present in p73, with several colorectal patients showing unique and specific seroreactivity to the ΔNp73 proteoforms. Overall, we have increased the complexity of the humoral immune response to the p53-family in cancer patients, showing that the proteoforms derived from the alternative splicing of p73 possess a higher diagnostic ability than the canonical protein, which might be extensive for p53 and p63 proteins.

Importance of endoscopist quality metrics for findings at surveillance colonoscopy: The detection-surveillance paradox.

BACKGROUND: Guidelines recommend surveillance colonoscopies based exclusively on findings at baseline colonoscopy. This recommendation leads to the paradox that the higher the baseline colonoscopy quality, the more surveillance colonoscopies will be indicated according to current guidelines. OBJECTIVE: The aim of this study was to evaluate the effect on follow-up findings of different quality metrics of the endoscopist performing the baseline colonoscopy. METHODS: This retrospective cohort study included individuals with advanced adenomas at baseline colonoscopy. Adenoma detection rate (ADR) and adenomas per colonoscopy rate (APCR) were determined for 44 endoscopists. Surveillance colonoscopies were checked after systematic tracking. RESULTS: A total of 574 individuals were diagnosed with advanced adenomas, of whom 270 received a surveillance colonoscopy. Patients whose baseline colonoscopy endoscopist had an ADR lower than the median of 33.8% had significantly higher rates of advanced neoplasia at follow-up (13.1% vs 4.0%; p = 0.001). On univariate analysis, high-risk advanced adenomas at baseline (HR 0.43; 95% CI 0.19-0.97) and ADR (HR 0.94; 95% CI 0.89-0.99) showed a significant relationship with advanced neoplasia at surveillance. In a multivariate Cox model, the ADR of the endoscopist who performed the baseline colonoscopy was the only independent predictor of risk for developing advanced neoplasia at follow-up (HR 0.94; 95% CI 0.89-0.99). CONCLUSIONS: Our results suggest that the risk of identifying advanced adenomas at follow-up is closely related to the quality metrics of the endoscopist who performs the baseline colonoscopy.

Clinical management of patients with advanced Parkinson's disease treated with continuous intestinal infusion of levodopa/carbidopa.

Patients with Parkinson's disease often have a good initial response to dopaminergic therapy but later usually develop motor fluctuations and dyskinesia. In these patients, continuous infusion of levodopa-carbidopa intestinal gel (LCIG) allows for maintaining adequate dopamine levels and for improving motor and nonmotor symptoms, as well as quality of life and autonomy. Adequate candidate selection and follow-up are crucial for treatment success. Management should be multidisciplinary, and patient and caregiver education is a priority. This expert consensus document has been developed by a team of neurologists, gastroenterologists and nurses who have a vast experience in LCIG therapy, with an intention to provide knowledge and tools to facilitate patient management throughout all phases of LCIG treatment process.

Diagnóstico atípico mediante cápsula endoscópica: enfermedad de Whipple / Atypical diagnosis diagnosis by endoscopic capsule: Whipple´s disease

La enfermedad de Whipple es una infección sistémica crónica producida por el actinomiceto Tropheryma whipplei. Las pruebas endoscópicas son claves en el diagnóstico ya que permiten la toma de biopsia y su estudio anatomopatológico para el diagnóstico definitivo de esta entidad. Presentamos un caso de enfermedad de Whipple en el que la cápsula endoscópica, poco común para el diagnóstico de esta afección, fue clave para el mismo y su realización antes y después del tratamiento antibiótico permite describir la evolución macroscópica de los hallazgos en intestino delgado. Este caso ilustra la utilidad de la cápsula endoscópica al permitir un estudio completo del intestino delgado en esta enfermedad en la que hasta el 30% de los pacientes puede cursar con gastroscopia normal (AU)

Whipple´s disease is a chronic systemic infection produced by the actinomycete Tropheryma whipplei. Endoscopic tests are key in the diagnosis as they allow biopsy and histopathological examination for definitive diagnosis of this entity. We present a case of Whipple´s disease where capsule endoscopy, uncommon for the diagnosis of this condition, was essential for it and its performance before and after antibiotic treatment allows to describe the macroscopic evolution of the findings in the small bowel. This case illustrates the utility of capsule endoscopy to allow complete examination of the small bowel disease in which up to 30% of patients may present with normal endoscopy (AU)

Endoscopist characteristics that influence the quality of colonoscopy.

BACKGROUND AND STUDY AIM: Several factors have been shown to be related to colonoscopy quality; however, little is known about the effects of endoscopist factors. This study analyzed the influence of endoscopist-related characteristics on quality indicators for colonoscopy. PATIENTS AND METHODS: The study included 48 endoscopists who each performed at least 20 colonoscopies in the colonoscopy arm of a randomized controlled trial comparing fecal immunochemical test vs. colonoscopy in colorectal cancer screening. These endoscopists performed a total of 3838 procedures in the trial. The following were calculated for each endoscopist: adenoma detection rate (ADR), advanced ADR, proximal ADR, distal ADR, and adenoma per colonoscopy rate (APCR). The characteristics of endoscopists were assessed with regard to colonoscopy quality using multivariate regression analysis. Endoscopist characteristics included age, sex, exclusive endoscopy practice, years as a physician, years as a specialist, specialty, total (life-long) number of colonoscopies performed, annual colonoscopy volume, number of hours/week dedicated to endoscopy and number of educational activities in the previous year. RESULTS: Factors associated with ADR were age of the endoscopist (odds ratio [OR] 1.11, 95 % confidence interval [CI] 1.01 - 1.21; P = 0.01) and life-long number of colonoscopies (OR 1.06, 95 %CI 1.01 - 1.11; P = 0.01). Only exclusive dedication to endoscopy practice was found to be independently related to proximal ADR (OR 1.71, 95 %CI 1.15 - 2.74; P = 0.001). Life-long number of colonoscopies was independently related to detection of distal adenomas (OR 1.07, 95 %CI 1.01 - 1.13; P = 0.01). None of the analyzed endoscopist characteristics was associated with advanced ADR or APCR. CONCLUSIONS: This study found that the experience of the endoscopist and exclusive dedication to endoscopy practice, but not annual colonoscopy volume, were associated with better colonoscopy quality.

Atypical diagnosis diagnosis by endoscopic capsule: Whipple's disease.

Whipple's disease is a chronic systemic infection produced by the actinomycete Tropheryma whipplei. Endoscopic tests are key in the diagnosis as they allow biopsy and histopathological examination for definitive diagnosis of this entity. We present a case of Whipple's disease where capsule endoscopy, uncommon for the diagnosis of this condition, was essential for it and its performance before and after antibiotic treatment allows to describe the macroscopic evolution of the findings in the small bowel. This case illustrates the utility of capsule endoscopy to allow complete examination of the small bowel disease in which up to 30% of patients may present with normal endoscopy.

In vivo gastric detection of α-synuclein inclusions in Parkinson's disease.

α-Synuclein inclusions have been identified in the brain and some parts of the enteric nervous system in Parkinson's disease cases. We aimed to assess these inclusions in gastric mucosa samples from patients with symptomatic Parkinson's disease. Random biopsies were performed by gastroscopy in 28 patients with Parkinson's disease and in 29 age- and sex-matched controls. Gastroscopy was performed to start enteral levodopa (L-dopa) therapy in cases and for diagnostic purposes in controls (gastroesophageal reflux, anemia, and abdominal pain were the main indications). The clinical definition of cases and controls was made a priori. Six controls had data suggestive of "mild presymptomatic parkinsonism". Biopsy specimens were immunostained for α-synuclein. The neuropathological diagnosis was established post hoc. No differences were found in the baseline characteristics of the groups. Positive fibers for the α-synuclein protein were observed in 17 of 28 (60.7%) Parkinson's disease patients, 1 of 23 controls (4.3%), and 1 of 6 (16.7%) cases of incident "mild presymptomatic parkinsonism." Neuropathological diagnosis based on α-synuclein immunostaining showed a sensitivity of 85% (95% confidence interval [CI] 62.1-96.8), specificity of 95% (95% CI 76.2-99.9) and area under the receiver operating characteristics curve (AUC) of 0.90 (95% CI 0.80-1.00). No adverse events occurred. Detection of α-synuclein inclusions in the gastric mucosa is a useful and safe tool providing in vivo evidence of the underlying neurodegenerative peripheral involvement linked to Parkinson's disease. Further studies are warranted to determine its pathophysiological implications.

Levodopa infusion improves impulsivity and dopamine dysregulation syndrome in Parkinson's disease.

BACKGROUND: Impulsivity and dopamine dysregulation syndrome are frequent complications of treatment in Parkinson's disease (PD). METHODS: We assessed the effect of jejunal levodopa infusion (JLI) on behavioral symptoms in 8 PD patients with motor complications and severe impulsivity and dopamine dysregulation syndrome (DDS), which had not be controlled before by adjusting oral medications. The infusion was delivered during 15 hours (daily dose 1007.2 ± 302.5 mg) and stopped at night time. Patients were reassessed after 25 ± 9 weeks of treatment with a stable dose of jejunal l-dopa. RESULTS: Off periods and dyskinesias decreased by 27% and 20,7% respectively, compared to baseline. DDS and all types of impulse control disorders (ICDs) improved in all patients, with nearly complete symptom resolution. Punding improved in all 5 patients but disappeared completely in only 1. CONCLUSIONS: Our experience suggests that l-dopa infusion has a positive effect on both motor complications and behavioral disorders. This treatment approach deserves further controlled studies.

Modifiable endoscopic factors that influence the adenoma detection rate in colorectal cancer screening colonoscopies.

BACKGROUND: Adenoma detection rate (ADR) has become the most important quality indicator for colonoscopy. OBJECTIVE: The aim of this study was to investigate which modifiable factors, directly related to the endoscopic procedure, influenced the ADR in screening colonoscopies. DESIGN: Observational, nested study. SETTING: Multicenter, randomized, controlled trials. PATIENTS: Asymptomatic people aged 50 to 69 years were eligible for a multicenter, randomized, controlled trial designed to compare colonoscopy and fecal immunochemical testing in colorectal cancer screening. A total of 4539 individuals undergoing a direct screening colonoscopy were included in this study. INTERVENTION: Colonoscopy. MAIN OUTCOME MEASUREMENTS: Bowel cleansing, sedation, withdrawal time in normal colonoscopies, and cecal intubation were analyzed as possible predictors of adenoma detection by using logistic regression analysis, adjusted for age and sex. RESULTS: In multivariate analysis, after adjustment for age and sex, factors independently related to the ADR were a mean withdrawal time longer than 8 minutes (odds ratio [OR] 1.51; 95% CI, 1.17-1.96) in normal colonoscopies and split preparation (OR 1.26; 95% CI, 1.01-1.57). For advanced adenomas, only withdrawal time maintained statistical significance in the multivariate analysis. For proximal adenomas, withdrawal time and cecal intubation maintained independent statistical significance, whereas only withdrawal time longer than 8 minutes and a <10-hour period between the end of preparation and colonoscopy showed independent associations for distal adenomas. LIMITATIONS: Only endoscopic variables have been analyzed. CONCLUSION: Withdrawal time was the only modifiable factor related to the ADR in colorectal cancer screening colonoscopies associated with an increased detection rate of overall, advanced, proximal, and distal adenomas.

Evaluation of different bowel preparations for small bowel capsule endoscopy: a prospective, randomized, controlled study.

BACKGROUND AND STUDY AIMS: To obtain an adequate view of the whole small intestine during capsule endoscopy (CE) a clear liquid diet and overnight fasting is recommended. However, intestinal content can hamper vision in spite of these measures. Our aim was to evaluate tolerance and degree of intestinal cleanliness during CE following three types of bowel preparation. PATIENTS AND METHODS: This was a prospective, multicenter, randomized, controlled study. Two-hundred ninety-one patients underwent one of the following preparations: 4 L of clear liquids (CL) (group A; 92 patients); 90 mL of aqueous sodium phosphate (group B; 89 patients); or 4 L of a polyethylene glycol electrolyte solution (group C; 92 patients). The degree of cleanliness of the small bowel was classified by blinded examiners according to four categories (excellent, good, fair or poor). The degree of patient satisfaction, gastric and small bowel transit times, and diagnostic yield were measured. RESULTS: The degree of cleanliness did not differ significantly between the groups (P = 0.496). Interobserver concordance was fair (k = 0.38). No significant differences were detected between the diagnostic yields of the CE (P = 0.601). Gastric transit time was 35.7 ± 3.7 min (group A), 46.1 ± 8.6 min (group B) and 34.6 ± 5.0 min (group C) (P = 0.417). Small-intestinal transit time was 276.9 ± 10.7 min (group A), 249.7 ± 13.1 min (group B) and 245.6 ± 11.6 min (group C) (P = 0.120). CL was the best tolerated preparation. Compliance with the bowel preparation regimen was lowest in group C (P = 0.008). CONCLUSIONS: A clear liquid diet and overnight fasting is sufficient to achieve an adequate level of cleanliness and is better tolerated by patients than other forms of preparation.