Epigenetic regulation of p63 blocks squamous-to-neuroendocrine transdifferentiation in esophageal development and malignancy.

While cell fate determination and maintenance are important in establishing and preserving tissue identity and function during development, aberrant cell fate transition leads to cancer cell heterogeneity and resistance to treatment. Here, we report an unexpected role for the transcription factor p63 (Trp63/TP63) in the fate choice of squamous versus neuroendocrine lineage in esophageal development and malignancy. Deletion of p63 results in extensive neuroendocrine differentiation in the developing mouse esophagus and esophageal progenitors derived from human embryonic stem cells. In human esophageal neuroendocrine carcinoma (eNEC) cells, p63 is transcriptionally silenced by EZH2-mediated H3K27 trimethylation (H3K27me3). Upregulation of the major p63 isoform ΔNp63α, through either ectopic expression or EZH2 inhibition, promotes squamous transdifferentiation of eNEC cells. Together these findings uncover p63 as a rheostat in coordinating the transition between squamous and neuroendocrine cell fates during esophageal development and tumor progression.

Endoscopic Submucosal Dissection (ESD) Offers a Safer and More Cost-effective Alternative to Transanal Endoscopic Microsurgery (TEM): An International Collaborative Study.

BACKGROUND: Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are minimally invasive procedures that treat early rectal cancer (ERC). Both are effective treatments, yet there are very few studies comparing them. The aim of our study was to identify ideal candidates for each procedure. MATERIALS AND METHODS: Between January 2016 and November 2019, 204 ERC patients were managed with either ESD (n=101) or TEM (n=103) at 7 international centers. Data analyzed included clinical success, tumor characteristics, procedure info, and recurrence rates. RESULTS: Median tumor size was 40 mm±23.9 in the ESD group and 56 mm±27.9 in the TEM group, significantly larger in the latter ( P <0.00001). Average procedure time was 131.5±67.9 minutes in ESD group and 104.9±28.4 minutes in TEM group ( P =0.000347). Average hospital stay was 3.3±2.6 days in the ESD group and 4.7±0.7 days in the TEM group ( P <0.00001). Adverse event rate was 6.8% in the ESD group and 24% in the TEM group. There were no significant difference in the rate of en bloc resection, technical success, tumor location, necessity of additional procedures, and tumor recurrence rates. CONCLUSION: Compared with TEM, ESD is a safer procedure with shorter hospital stay and should be offered for patients who have ERC.

Digital single-operator cholangioscopy interobserver study using a new classification: the Mendoza Classification (with video).

BACKGROUND AND AIMS: Digital single-operator cholangioscopy (DSOC) allows direct visualization of the biliary tree for evaluation of biliary strictures. Our objective was to assess the interobserver agreement (IOA) of DSOC interpretation for indeterminate biliary strictures using newly refined criteria. METHODS: Fourteen endoscopists were asked to review an atlas of reference clips and images of 5 criteria derived from expert consensus. They then proceeded to score 50 deidentified DSOC video clips based on the visualization of tortuous and dilated vessels, irregular nodulations, raised intraductal lesions, irregular surface with or without ulcerations, and friability. The endoscopists then diagnosed the clips as neoplastic or non-neoplastic. Intraclass correlation (ICC) analysis was done to evaluate inter-rater agreement for both criteria sets and final diagnosis. RESULTS: Clips of 41 malignant lesions and 9 benign lesions were scored. Three of 5 revised criteria had almost perfect agreement. ICC was almost perfect for presence of tortuous and dilated vessels (.86), raised intraductal lesions (.90), and presence of friability (.83); substantial agreement for presence of irregular nodulations (.71); and moderate agreement for presence of irregular surface with or without ulcerations (.44). The diagnostic ICC was almost perfect for neoplastic (.90) and non-neoplastic (.90) diagnoses. The overall diagnostic accuracy using the revised criteria was 77%, ranging from 64% to 88%. CONCLUSIONS: The IOA and accuracy rate of DSOC using the new Mendoza criteria shows a significant increase of 16% and 20% compared with previous criteria. The reference atlas helps with formal training and may improve diagnostic accuracy. (Clinical trial registration number: NCT02166099.).

Gastric per-oral endoscopic myotomy versus pyloromyotomy for gastroparesis: An international comparative study.

BACKGROUND AND AIM: Gastroparesis is a potentially debilitating gastric motility disorder with limited treatment options. Highest efficacy treatments include gastric per-oral endoscopic myotomy (GPOEM) and surgical pyloromyotomy. This study compares the efficacy and safety of GPOEM versus laparoscopic pyloromyotomy for refractory gastroparesis. METHODS: Patients who underwent GPOEM or laparoscopic pyloromyotomy for refractory gastroparesis from four centers across the USA and Latin America were included in a dedicated registry. Data collected included patient demographics, imaging, laboratory values, clinical success, gastroparesis cardinal symptom index, procedure time, pre-op and post-op gastric emptying times, adverse events, and hospital length of stay. RESULTS: A total of 102 patients were included (mean age 47; 32.4% male): GPOEM n = 39, surgical pyloromyotomy n = 63.Technical success was 100% in both groups. Clinical success was 92.3% in the GPOEM group and 82.5% in the surgery group (P = 0.164). The GPOEM group had a significantly higher post-op GSCI score reduction by 1.3 units (P < 0.00001), post-op retention reduction at 2 h by 18% (P < 0.00001), post-op retention reduction at 4 h by 25% (P < 0.00001) and a lower procedure time by 20 min (P < 0.00001) as compared with surgery. GPOEM also had a lower hospital length of stay by 2.8 days (P < 0.00001). Adverse events were significantly fewer in the GPOEM group (13%) compared with surgery group (33.3%; P = 0.021). Mean blood loss in the GPOEM group was only 3.6 mL compared with 866 mL in the surgery group. CONCLUSIONS: The GPOEM may be a less invasive, safer, and more efficacious procedural treatment for refractory gastroparesis as compared with surgical pyloromyotomy.

The Learning Curve for Peroral Endoscopic Myotomy in Latin America: A Slide to the Right?

BACKGROUND/AIMS: Peroral endoscopic myotomy (POEM) has been increasingly used for achalasia in Latin America, where Chagas disease is prevalent, and this makes POEM more challenging. The aim of this study was to determine the learning curve for POEM in Latin America. METHODS: Patients undergoing POEM in Latin America with a single operator were included from a prospective registry over 4 years. Non-linear regression and cumulative sum control chart (CUSUM) analyses were conducted for the learning curve. RESULTS: A total of 125 patients were included (52% male; mean age, 59 years), of which 80 had type II achalasia (64%), and 38 had Chagas disease (30%). The average pre-procedure and post-procedure Eckardt scores were 6.79 and 1.87, respectively. Technical success was achieved in 93.5% of patients, and clinical success was achieved in 88.8%. Adverse events occurred in 27 patients (22%) and included bleeding (4 patients), pneumothorax (4 patients), mucosal perforation (13 patients), mediastinitis (2 patients), and leakage (4 patients).
The CUSUM chart showed a median procedure time of 97 min (range, 45-196 min), which was achieved at the 61st procedure. Procedure duration progressively decreased, with the last 10 procedures under 50 min approaching a plateau (p-value <0.01). CONCLUSION: Mastering POEM in Latin America requires approximately 61 procedures for both POEM efficiency and to accomplish the procedure within 97 minutes.

How does per-oral endoscopic myotomy compare to Heller myotomy? The Latin American perspective.

Background and study aims Both Heller myotomy (HM) and per-oral endoscopic myotomy (POEM) are efficacious therapies for achalasia. The efficacy and safety of POEM vs HM in Latin America and specifically in patients with Chagas disease is unknown. Patients and methods Consecutive patients undergoing either HM or POEM for achalasia were included from nine Latin American centers in a prospective registry over 5 years. Technical success was defined as undergoing a successful myotomy. Clinical success was defined as achieving an Eckardt score < 3. Data on demographics, procedure info, Eckardt score, and adverse events (AEs) were collected. Student's t test, Chi squared, and logistic regression analyses were conducted. Results One hundred thirty-three patients were included (59 male; 44 %; mean age 47). POEM was performed in 69 patients, HM in 64 patients. A total of 35 patients had Chagas disease, 17 of 69 in the POEM group, 18 of 64 in the HM group. Both groups had significant reduction in Eckardt scores ( P  < 0.00001), but successful initial therapy was significantly higher in the POEM group compared to the HM group ( P  = 0.01304). AEs were similar in both group (17 % vs 14 %) and consisted of pneumothorax (n = 3 vs 2), bleeding requiring transfusion (n = 3 vs 2), and mediastinitis (n = 3 vs 1). Hospital stay was longer in the HM group than in the POEM group ( P  < 0.00001). In the Chagas subgroup, post-procedure Eckardt score in the POEM group was significantly reduced by 5.71 points ( P  < 0.00001) versus 1.56 points in the HM group ( P  = 0.042793). Conclusion Both HM and POEM are efficacious for achalasia, but POEM was associated with higher initial therapy success and shorter hospital stay in Latin America. In Chagas patients with achalasia, POEM was significantly more effective than HM.

Use of hPSC-derived 3D organoids and mouse genetics to define the roles of YAP in the development of the esophagus.

Balanced progenitor activities are crucial for the development and maintenance of high turn-over organs such as the esophagus. However, the molecular mechanisms regulating these progenitor activities in the esophagus remain to be elucidated. Here, we demonstrated that Yap is required for the proliferation of esophageal progenitor cells (EPCs) in the developing murine esophagus. We found that Yap deficiency reduces EPC proliferation and stratification whereas persistent Yap activation increases cell proliferation and causes aberrant stratification of the developing esophagus. We further demonstrated that the role of YAP signaling is conserved in the developing human esophagus by utilizing 3D human pluripotent stem cell (hPSC)-derived esophageal organoid culture. Taken together, our studies combining loss/gain-of-function murine models and hPSC differentiation support a key role for YAP in the self-renewal of EPCs and stratification of the esophageal epithelium.

Profile and Outcome of Pediatric Brain Tumors - Experience from a Tertiary Care Pediatric Oncology Unit in South India.

CONTEXT: Tumors of the central nervous system (CNS) constitute the second most common pediatric cancers. Unlike leukemia, management of CNS tumors requires a good multidisciplinary team. Higher rates of treatment abandonment are documented in view of complexity of the treatment with long duration, involving neurosurgery, radiation, chemotherapy, and high cost of treatment. Morbidity associated with CNS tumors may be significant in terms of physical deficits as well as neuropsychological and neuroendocrine sequelae. Pediatric neurooncology is still at a very nascent stage in the developing countries. There are only a few reports on the multidisciplinary approach and outcomes of pediatric brain tumors in developing countries. AIMS: The aim of this study is to identify the clinicopathological profile of Pediatric CNS tumors in a tertiary care center located in South India in comparison with reports from other low-and middle-income Countries. SETTINGS AND DESIGN: A retrospective analysis of medical records of all children diagnosed with brain tumors from January 2012 to November 2016 at our institute was done. SUBJECTS AND METHODS: A retrospective study of clinical, pathological profile, and outcomes of children <18 years diagnosed with brain tumors at our institute from January 2012 to November 2016 was done. Histopathological categorization was done as per the WHO classification 2007. The multidisciplinary treatment with respect to surgery, radiation, and chemotherapy was noted and the outcomes were recorded. STATISTICAL ANALYSIS USED: R for Statistical Computing (Version 3.0.2; 2013-09-25). RESULTS: A total of 52 children were diagnosed with male preponderance of 66.6%. Highest incidence was noted in the age group of 0-4 years (50%). Majority of them were supratentorial (59.6%). CNS embryonal tumors contributed to 48% of all our brain tumors. 73% of them underwent either resection or biopsy. Eight (15.3%) of them died due to the progression of disease, but 44% abandoned treatment due to the progression/recurrence of disease. Those lost to follow-up were mostly among the high-risk groups with poor prognosis such as pontine glioma, medulloblastoma (high risk), and primitive neuroectodermal tumor. CONCLUSIONS: Although brain tumors constituted 30% of all our solid tumors, only 56% of them received appropriate treatment and 25% abandoned treatment. High rates of abandonment were a consequence of late diagnosis, complex multidisciplinary treatment involved, high treatment cost, lack of uniformity in management between different oncology centers and poor prognosis of the tumor subtype.