Microscopic Small Airway Abnormalities Identified in Early Idiopathic Pulmonary Fibrosis In Vivo Using Endobronchial Optical Coherence Tomography.

Rationale: Idiopathic pulmonary fibrosis (IPF) affects the subpleural lung but is considered to spare small airways. Micro-computed tomography (micro-CT) studies demonstrated small airway reduction in end-stage IPF explanted lungs, raising questions about small airway involvement in early-stage disease. Endobronchial optical coherence tomography (EB-OCT) is a volumetric imaging modality that detects microscopic features from subpleural to proximal airways. Objectives: In this study, EB-OCT was used to evaluate small airways in early IPF and control subjects in vivo. Methods: EB-OCT was performed in 12 subjects with IPF and 5 control subjects (matched by age, sex, smoking history, height, and body mass index). Subjects with IPF had early disease with mild restriction (FVC: 83.5% predicted), which was diagnosed per current guidelines and confirmed by surgical biopsy. EB-OCT volumetric imaging was acquired bronchoscopically in multiple, distinct, bilateral lung locations (total: 97 sites). IPF imaging sites were classified by severity into affected (all criteria for usual interstitial pneumonia present) and less affected (some but not all criteria for usual interstitial pneumonia present). Bronchiole count and small airway stereology metrics were measured for each EB-OCT imaging site. Measurements and Main Results: Compared with the number of bronchioles in control subjects (mean = 11.2/cm3; SD = 6.2), there was significant bronchiole reduction in subjects with IPF (42% loss; mean = 6.5/cm3; SD = 3.4; P = 0.0039), including in IPF affected (48% loss; mean: 5.8/cm3; SD: 2.8; P < 0.00001) and IPF less affected (33% loss; mean: 7.5/cm3; SD: 4.1; P = 0.024) sites. Stereology metrics showed that IPF-affected small airways were significantly larger, more distorted, and more irregular than in IPF-less affected sites and control subjects. IPF less affected and control airways were statistically indistinguishable for all stereology parameters (P = 0.36-1.0). Conclusions: EB-OCT demonstrated marked bronchiolar loss in early IPF (between 30% and 50%), even in areas minimally affected by disease, compared with matched control subjects. These findings support small airway disease as a feature of early IPF, providing novel insight into pathogenesis and potential therapeutic targets.

A Pilot Study Using Machine Learning Algorithms and Wearable Technology for the Early Detection of Postoperative Complications After Cardiothoracic Surgery.

OBJECTIVE: To evaluate whether a machine learning algorithm (i.e. the "NightSignal" algorithm) can be used for the detection of postoperative complications prior to symptom onset after cardiothoracic surgery. SUMMARY BACKGROUND DATA: Methods that enable the early detection of postoperative complications after cardiothoracic surgery are needed. METHODS: This was a prospective observational cohort study conducted from July 2021 to February 2023 at a single academic tertiary care hospital. Patients aged 18 years or older scheduled to undergo cardiothoracic surgery were recruited. Study participants wore a Fitbit watch continuously for at least 1 week preoperatively and up to 90-days postoperatively. The ability of the NightSignal algorithm-which was previously developed for the early detection of Covid-19-to detect postoperative complications was evaluated. The primary outcomes were algorithm sensitivity and specificity for postoperative event detection. RESULTS: A total of 56 patients undergoing cardiothoracic surgery met inclusion criteria, of which 24 (42.9%) underwent thoracic operations and 32 (57.1%) underwent cardiac operations. The median age was 62 (IQR: 51-68) years and 30 (53.6%) patients were female. The NightSignal algorithm detected 17 of the 21 postoperative events a median of 2 (IQR: 1-3) days prior to symptom onset, representing a sensitivity of 81%. The specificity, negative predictive value, and positive predictive value of the algorithm for the detection of postoperative events were 75%, 97%, and 28%, respectively. CONCLUSIONS: Machine learning analysis of biometric data collected from wearable devices has the potential to detect postoperative complications-prior to symptom onset-after cardiothoracic surgery.

Synthesis of Amphiphilic Amino Poly-Amido-Saccharide and Poly(lactic) Acid Block Copolymers and Fabrication of Paclitaxel-Loaded Mucoadhesive Nanoparticles.

Drug delivery to the esophagus through systemic administration remains challenging, as minimal drug reaches the desired target. Local delivery offers the potential for improved efficacy while minimizing off-target toxicities but necessitates bioadhesive properties for mucosal delivery. Herein, we describe the synthesis of two new mucoadhesive amphiphilic copolymers prepared by sequential ring-opening copolymerization or postpolymerization click conjugation. Both strategies yield block copolymers containing a hydrophilic amine-functionalized poly-amido-saccharide and either a hydrophobic alkyl derivatized poly-amido-saccharide or poly(lactic acid), respectively. The latter resulting copolymers readily self-assemble into spherical, ≈200 nm diameter, positively charged mucoadhesive nanoparticles. The NPs entrap ultrahigh levels of paclitaxel via encapsulation of free paclitaxel and paclitaxel conjugated to a biodegradable, biocompatible poly(1,2-glycerol carbonate). Paclitaxel-loaded NPs rapidly enter cells, release paclitaxel, are cytotoxic to esophageal OE33 and OE19 tumor cells in vitro, and, importantly, demonstrate improved mucoadhesion compared to conventional poly(ethylene glycol)-poly(lactic acid) nanoparticles to ex vivo esophageal tissue.

Contributing factors to lymph node recovery with esophagectomy by thoracic surgeons: an analysis of the Society of Thoracic Surgeons General Thoracic Surgery Database.

Given the association between lymphadenectomy and survival after esophagectomy, and the ongoing development of effective adjuvant protocols for identified residual disease, we determined factors contributing to lymph node yield and effects on postoperative morbidity following esophagectomy by thoracic surgeons. Using the Society of Thoracic Surgeons General Thoracic Surgery Database, all patients who underwent esophagectomy for primary esophageal cancer with gastric conduit reconstruction from 2012 to 2016 were identified. Patient demographics, technical factors, and tumor characteristics associated with lymph node yield were determined using a multivariable multilevel mixed-effects regression model. Associations between lymph node yield and perioperative morbidity and mortality were similarly assessed. A total of 8480 patients were included. The median number of nodes harvested was 16 [Interquartile Range 11-22]. Factors associated with fewer nodes included female gender (b=-0.53, P=0.032), body mass index <18.5 (b=-1.46, P=0.012), prior cardiothoracic surgery (b=-0.73, P=0.015), intraoperative blood transfusion (b=-1.43, P<0.001), squamous cell histology (b=-0.86, P=0.006), and neoadjuvant treatment (b=-1.41, P<0.001). Operative approach significantly affected lymph node yield, with minimally invasive approaches demonstrating higher lymph node counts, and open transhiatal esophagectomy recovering the fewest nodes. Findings were independent of clinical center. There was no association of higher lymph node yield with 30-day mortality, with only slightly increased risk for chyle leak (odds ratio [OR] 1.02, P=0.012). In conclusion, several patient and tumor factors affect lymph node recovery with esophagectomy, independent of hospital center. Technical aspects, specifically minimally invasive approach, play a significant role in quantified lymph node yield. Higher operative lymph node yield was associated with minimal increased morbidity.

Hypoxia promotes isocitrate dehydrogenase-dependent carboxylation of α-ketoglutarate to citrate to support cell growth and viability.

Citrate is a critical metabolite required to support both mitochondrial bioenergetics and cytosolic macromolecular synthesis. When cells proliferate under normoxic conditions, glucose provides the acetyl-CoA that condenses with oxaloacetate to support citrate production. Tricarboxylic acid (TCA) cycle anaplerosis is maintained primarily by glutamine. Here we report that some hypoxic cells are able to maintain cell proliferation despite a profound reduction in glucose-dependent citrate production. In these hypoxic cells, glutamine becomes a major source of citrate. Glutamine-derived α-ketoglutarate is reductively carboxylated by the NADPH-linked mitochondrial isocitrate dehydrogenase (IDH2) to form isocitrate, which can then be isomerized to citrate. The increased IDH2-dependent carboxylation of glutamine-derived α-ketoglutarate in hypoxia is associated with a concomitant increased synthesis of 2-hydroxyglutarate (2HG) in cells with wild-type IDH1 and IDH2. When either starved of glutamine or rendered IDH2-deficient by RNAi, hypoxic cells are unable to proliferate. The reductive carboxylation of glutamine is part of the metabolic reprogramming associated with hypoxia-inducible factor 1 (HIF1), as constitutive activation of HIF1 recapitulates the preferential reductive metabolism of glutamine-derived α-ketoglutarate even in normoxic conditions. These data support a role for glutamine carboxylation in maintaining citrate synthesis and cell growth under hypoxic conditions.

Updates in Translational Science for Esophageal and Gastric Cancers.

In this article, the authors summarize the current state of translational science for esophageal and gastric cancers. The available targeted therapies, immunotherapies, and recently discovered molecular targets are reviewed. The authors introduce circulating tumor deoxyribonucleic acid and its promise as a biomarker to detect disease recurrence. The authors present patient-derived organoids as a new model for studying carcinogenesis and treatment responses. Finally, we discuss the implications of organoid models for precision oncology and describe exciting new work applying gene editing technology to organoids and studying tumor-microenvironment interactions using 3-dimensional co-culture systems.

AMPK Activation Serves as a Common Pro-Survival Pathway in Esophageal Adenocarcinoma Cells.

Esophageal adenocarcinoma (EAC) is a subtype of esophageal cancer that is difficult to treat, with overall poor survival and frequent recurrence despite curative-intent treatment strategies. There is limited understanding of EAC resistance mechanisms to chemotherapy or radiation. We have found that the AMP-activated protein kinase (AMPK) can serve a pro-survival function in EAC cells in response to cytotoxic treatments. Treatment with the IL-6 inhibitor tocilizumab, which previously has been shown to inhibit EAC organoid growth, resulted in the activation of AMPK in the OE33 EAC cell line, which was accompanied by a decrease in MTORC1 signaling and an increase in oxidative mitochondrial metabolism, both known downstream effects of AMPK activation to promote cell survival under conditions of metabolic stress. This increase in oxidative metabolism was abrogated in cells with a genetic knockdown of AMPK expression. Furthermore, we found that AMPK was activated in OE33 cells following treatment with cisplatin or ionizing radiation. Treatment with the AMPK inhibitor Compound C or genetic knockdown of AMPK expression enhanced cell death in a synergistic manner with chemotherapeutics or ionizing radiation. These findings were recapitulated in human patient-derived EAC organoids, suggesting that AMPK may be a common pro-survival mechanism to confer treatment resistance in EAC and may serve as a novel target to enhance the efficacy of current and future treatment strategies.

Modeling Epithelial Homeostasis and Perturbation in Three-Dimensional Human Esophageal Organoids.

Background: Esophageal organoids from a variety of pathologies including cancer are grown in Advanced Dulbecco's Modified Eagle Medium-Nutrient Mixture F12 (hereafter ADF). However, the currently available ADF-based formulations are suboptimal for normal human esophageal organoids, limiting the ability to compare normal esophageal organoids with those representing a given disease state. Methods: We have utilized immortalized normal human esophageal epithelial cell (keratinocyte) lines EPC1 and EPC2 and endoscopic normal esophageal biopsies to generate three-dimensional (3D) organoids. To optimize the ADF-based medium, we evaluated the requirement of exogenous epidermal growth factor (EGF) and inhibition of transforming growth factor-(TGF)-ß receptor-mediated signaling, both key regulators of the proliferation of human esophageal keratinocytes. We have modeled human esophageal epithelial pathology by stimulating esophageal 3D organoids with interleukin (IL)-13, an inflammatory cytokine, or UAB30, a novel pharmacological activator of retinoic acid signaling. Results: The formation of normal human esophageal 3D organoids was limited by excessive EGF and intrinsic TGFß-receptor-mediated signaling. Optimized HOME0 improved normal human esophageal organoid formation. In the HOME0-grown organoids, IL-13 and UAB30 induced epithelial changes reminiscent of basal cell hyperplasia, a common histopathologic feature in broad esophageal disease conditions including eosinophilic esophagitis. Conclusions: HOME0 allows modeling of the homeostatic differentiation gradient and perturbation of the human esophageal epithelium while permitting a comparison of organoids from mice and other organs grown in ADF-based media.

Modeling epithelial homeostasis and perturbation in three-dimensional human esophageal organoids.

Background: Esophageal organoids from a variety of pathologies including cancer are grown in Advanced Dulbecco's Modified Eagle Medium-Nutrient Mixture F12 (hereafter ADF). However, the currently available ADF-based formulations are suboptimal for normal human esophageal organoids, limiting the ability to compare normal esophageal organoids with those representing a given disease state. Methods: We have utilized immortalized normal human esophageal epithelial cell (keratinocyte) lines EPC1 and EPC2 and endoscopic normal esophageal biopsies to generate three-dimensional (3D) organoids. To optimize ADF-based medium, we evaluated the requirement of exogenous epidermal growth factor (EGF) and inhibition of transforming growth factor-(TGF)-ß receptor-mediated signaling, both key regulators of proliferation of human esophageal keratinocytes. We have modeled human esophageal epithelial pathology by stimulating esophageal 3D organoids with interleukin (IL)-13, an inflammatory cytokine, or UAB30, a novel pharmacological activator of retinoic acid signaling. Results: The formation of normal human esophageal 3D organoids was limited by excessive EGF and intrinsic TGFß receptor-mediated signaling. In optimized HOME0, normal human esophageal organoid formation was improved, whereas IL-13 and UAB30 induced epithelial changes reminiscent of basal cell hyperplasia, a common histopathologic feature in broad esophageal disease conditions including eosinophilic esophagitis. Conclusions: HOME0 allows modeling of the homeostatic differentiation gradient and perturbation of the human esophageal epithelium while permitting a comparison of organoids from mice and other organs grown in ADF-based media.

Disrupting CD38-driven T cell dysfunction restores sensitivity to cancer immunotherapy.

A central problem in cancer immunotherapy with immune checkpoint blockade (ICB) is the development of resistance, which affects 50% of patients with metastatic melanoma1,2. T cell exhaustion, resulting from chronic antigen exposure in the tumour microenvironment, is a major driver of ICB resistance3. Here, we show that CD38, an ecto-enzyme involved in nicotinamide adenine dinucleotide (NAD+) catabolism, is highly expressed in exhausted CD8+ T cells in melanoma and is associated with ICB resistance. Tumour-derived CD38hiCD8+ T cells are dysfunctional, characterised by impaired proliferative capacity, effector function, and dysregulated mitochondrial bioenergetics. Genetic and pharmacological blockade of CD38 in murine and patient-derived organotypic tumour models (MDOTS/PDOTS) enhanced tumour immunity and overcame ICB resistance. Mechanistically, disrupting CD38 activity in T cells restored cellular NAD+ pools, improved mitochondrial function, increased proliferation, augmented effector function, and restored ICB sensitivity. Taken together, these data demonstrate a role for the CD38-NAD+ axis in promoting T cell exhaustion and ICB resistance, and establish the efficacy of CD38 directed therapeutic strategies to overcome ICB resistance using clinically relevant, patient-derived 3D tumour models.

Tumor-Derived CCL5 Recruits Cancer-Associated Fibroblasts and Promotes Tumor Cell Proliferation in Esophageal Squamous Cell Carcinoma.

Cancer-associated fibroblasts (CAF) can promote tumor growth, metastasis, and therapeutic resistance in esophageal squamous cell carcinoma (ESCC), but the mechanisms of action remain elusive. Our objective was to identify secreted factor(s) that mediate the communication between CAFs and ESCC tumor cells with the aim of identifying potential druggable targets. Through unbiased cytokine arrays, we have identified CC motif chemokine ligand 5 (CCL5) as a secreted factor that is increased upon co-culture of ESCC cells and CAFs, which we replicated in esophageal adenocarcinoma (EAC) with CAFs. Loss of tumor-cell-derived CCL5 reduces ESCC cell proliferation in vitro and in vivo and we propose this is mediated, in part, by a reduction in ERK1/2 signaling. Loss of tumor-derived CCL5 reduces the percentage of CAFs recruited to xenograft tumors in vivo. CCL5 is a ligand for the CC motif receptor 5 (CCR5), for which a clinically approved inhibitor exists, namely Maraviroc. Maraviroc treatment reduced tumor volume, CAF recruitment, and ERK1/2 signaling in vivo, thus, mimicking the effects observed with genetic loss of CCL5. High CCL5 or CCR5 expression is associated with worse prognosis in low-grade esophageal carcinomas. IMPLICATIONS: These data highlight the role of CCL5 in tumorigenesis and the therapeutic potential of targeting the CCL5-CCR5 axis in ESCC.

Food Deserts Increase Readmission After Esophagectomy for Cancer: A Multi-institutional Study.

BACKGROUND: Food deserts are low-income census tracts with poor access to supermarkets and are associated with worse outcomes in breast, colon, and a small number of esophageal cancer patients. This study investigated residency in food deserts on readmission rates in a multi-institutional cohort of esophageal cancer patients undergoing trimodality therapy. METHODS: A retrospective review of patients who underwent trimodality therapy at 6 high-volume institutions from January 2015 to July 2019 was performed. Food desert status was defined by the United States Department of Agriculture by patient ZIP Code. The primary outcome was 30-day readmission after esophagectomy. Multilevel, multivariable logistic regression was used to model readmission on food desert status adjusted for diabetes, insurance type, length of stay, and any complication, treating the institution as a random factor. RESULTS: Of the 453 records evaluated, 425 were included in the analysis. Seventy-three patients (17.4%) resided in a food desert. Univariate analysis demonstrated food desert patients had significantly increased 30-day readmission. No differences were seen in length of stay, complications, or 30-day mortality. In the adjusted logistic regression model, residing in a food desert remained a significant risk factor for readmission (odds ratio, 2.11; 95% CI, 1.07-4.15). There were no differences in 30-day, 90-day, or 1-year mortality based on food desert status, although readmission was associated with worse 90-day and 1-year mortality. CONCLUSIONS: Food desert residence was associated with 30-day readmission after esophagectomy in patients undergoing trimodality treatment for esophageal cancer in this multi-institutional population. Identification of patients residing in a food desert may allow surgeons to focus preventative interventions during treatment and postoperatively to improve outcomes.

Advances in Imaging to Aid Segmentectomy for Lung Cancer.

Pulmonary segmentectomy has become a widely accepted technique for resection of early-stage lung cancers. Intraoperative identification of small nodules within the lung parenchyma and definition of segmental anatomy are essential for oncologic segmental resection and significantly enhanced by recent advances in imaging techniques. Advances in imaging for nodule localization, using preoperative markers and three-dimensional computed tomography, delineation of segmental anatomy, and sentinel lymph node mapping have become important components of planning and performing minimally invasive anatomic segmentectomies and are particularly well suited for the evolving robotic-assisted platform.

Intraoperative fluorescence imaging in esophagectomy and its application to the robotic platform: a narrative review.

Background and Objective: Robotic-assisted esophagectomy is an approach to minimally invasive esophagectomy (MIE) that has demonstrated equivalent or improved outcomes relative to open and other minimally invasive techniques. The robotic approach also allows unique opportunities to improve complications following esophagectomy through use of enhanced visualization tools, including intraoperative fluorescence imaging. In this review, we summarize the specific uses of intraoperative fluorescence imaging as an adjunct tool during esophagectomy and discuss its application to the robotic platform. Methods: A literature search was conducted via PubMed in February 2022 with the following keywords: esophagectomy, esophageal cancer, infrared, near-infrared (NIR) and fluorescence. Peer-reviewed academic journal articles published in English between 2000 and 2021 were included. Key Content and Findings: There is a growing body of literature evaluating the use of intraoperative fluorescence imaging in robotic-assisted esophagectomy. This includes assessment of gastric conduit perfusion, including feasibility, creation of the gastroesophageal anastomosis, and qualification of perfusion, along with lymphatic mapping and identification of critical anatomy. These tools are uniquely leveraged using the robotic platform to standardize and quantify key technical aspects of the operation. Conclusions: Intraoperative fluorescence imaging provides the opportunity to assess perfusion and identify anatomy for more precise and patient-specific dissection and reconstruction. Among all the operative techniques for esophagectomy, robotic-assisted esophagectomy is uniquely suited to utilize these imaging modalities to optimize outcomes and minimize risk associated with esophagectomy.

Early vs Delayed Surgery for Esophageal Cancer During the COVID-19 Pandemic.

BACKGROUND: During the coronavirus disease 2019 pandemic, national guidelines recommended that elective surgery for esophageal cancer be deferred by 3 months when hospital resources are limited. The impact of this delay on patient outcomes is unknown. We sought to evaluate the survival of patients with stage I and II/III esophageal cancer who undergo early vs delayed treatment. STUDY DESIGN: Using the National Cancer Database from 2010 to 2017, multivariable Cox proportional hazards modeling and propensity score-matched analysis were employed to compare survival of patients with stage I esophageal cancer who received early (0 to 4 weeks after diagnosis) vs delayed esophagectomy (12 to 16 weeks) and of patients with stage II/III esophageal cancer who-after receiving timely chemoradiation (0 to 4 weeks after diagnosis)-underwent early (9 to 17 weeks) vs delayed esophagectomy (21 to 29 weeks). RESULTS: For stage I esophageal cancer, 226 (41.7%) patients underwent early esophagectomy, and 316 (58.3%) patients underwent delayed esophagectomy. Propensity score matching created 2 groups of 134 patients with early or delayed esophagectomy, whose 5-year survival was comparable (hazard ratio [HR] 65.0% [95% confidence interval (CI) 55.2% to 73.2%] vs HR 65.1% [95% CI 55.6% to 73.1%], p = 0.50). For stage II/III esophageal cancer, 1,236 (86.1%) patients underwent early esophagectomy, and 200 (13.9%) underwent delayed esophagectomy. Propensity score matching created 2 groups of 130 patients; the early esophagectomy group had improved 5-year survival compared with the delayed esophagectomy group (HR 41.6% [95% CI 32.1% to 50.8%] vs HR 22.9% [95% CI 14.9% to 31.8%], p = 0.006). CONCLUSIONS: Early esophagectomy was associated with similar survival compared with delayed esophagectomy for patients with stage I esophageal cancer. For patients with stage II/III esophageal cancer, early esophagectomy was associated with improved survival relative to delayed esophagectomy.

Understanding the cellular origin and progression of esophageal cancer using esophageal organoids.

Three-dimensional (3D) organoids are a novel tool to model epithelial cell biology and human diseases of the esophagus. 3D organoid culture systems have been utilized to investigate the pathobiology of esophageal cancer, including both squamous cell carcinoma and adenocarcinoma. Additional organoid-based approaches for study of esophageal development and benign esophageal diseases have provided key insights into esophageal keratinocyte differentiation and mucosal regeneration. These investigations have implications for the identification of esophageal cancer stem cells, as well as the potential to halt malignant progression through induction of differentiation pathways. Patient-derived organoids (PDOs) from human tissue samples allow for unique and faithful in vitro modeling of esophageal cancers, and provide an exciting platform for investigation into personalized medicine and targeted treatment approaches, as well as new models for understanding therapy resistance and recurrent disease. Future directions include high-throughput genomic screening using PDOs, and study of tumor-microenvironmental interactions through co-culture with immune and stromal cells and novel extracellular matrix complexes.

Impact of Obesity on Treatment Approach for Resectable Esophageal Cancer.

BACKGROUND: With the prevalence of obesity and its known association with esophageal cancer, there is increasing need to understand how obesity affects treatment. METHODS: Using The Society of Thoracic Surgeons General Thoracic Surgery Database, we retrospectively evaluated all patients who underwent esophagectomy with gastric conduit reconstruction between 2012 and 2016. Patients were categorized into five body mass index groups. Associations between body mass index and surgical technique, resection, lymphadenectomy, staging, and neoadjuvant treatment were evaluated using multivariable logistic regression models. RESULTS: In all, 8547 patients were included in the analysis. Obese and morbidly obese patients were more likely to undergo open procedures compared with normal-weight patients (odds ratio [OR] 1.18, P = .016; and OR 1.45, P = .007), with longer operative times. Morbidly obese patients had a higher rate of intraoperative conversion from minimally invasive to open approaches (OR 3.75, P = .001). There were no differences in R0 resection or lymphadenectomy, and staging workup was similar. Obese patients were less likely to receive neoadjuvant therapy (OR 0.75, P = .048), and overweight and obese patients were less likely to receive preoperative radiation (OR 0.75, P = .017; and OR 0.71, P = .010). Analyzing by stage, overweight and obese patients with cT2N0 disease were less likely to receive neoadjuvant treatment (OR 0.54, P = .016; and OR 0.37, P < .001). There were no differences in neoadjuvant therapy for cT3 or node-positive disease. CONCLUSIONS: Higher body mass index is associated with increased use of open versus minimally invasive esophagectomy and intraoperative conversion. Whereas staging workup and oncologic outcomes of surgery are similar, overweight and obese patients with cT2N0 disease are less likely to undergo neoadjuvant treatments.

LIN28B induces a differentiation program through CDX2 in colon cancer.

Most colorectal cancers (CRCs) are moderately differentiated or well differentiated, a status that is preserved even in metastatic tumors. However, the molecular mechanisms underlying CRC differentiation remain to be elucidated. Herein, we unravel a potentially novel posttranscriptional regulatory mechanism via a LIN28B/CDX2 signaling axis that plays a critical role in mediating CRC differentiation. Owing to a large number of mRNA targets, the mRNA-binding protein LIN28B has diverse functions in development, metabolism, tissue regeneration, and tumorigenesis. Our RNA-binding protein IP (RIP) assay revealed that LIN28B directly binds CDX2 mRNA, which is a pivotal homeobox transcription factor in normal intestinal epithelial cell identity and differentiation. Furthermore, LIN28B overexpression resulted in enhanced CDX2 expression to promote differentiation in subcutaneous xenograft tumors generated from CRC cells and metastatic tumor colonization through mesenchymal-epithelial transition in CRC liver metastasis mouse models. A ChIP sequence for CDX2 identified α-methylacyl-CoA racemase (AMACR) as a potentially novel transcriptional target of CDX2 in the context of LIN28B overexpression. We also found that AMACR enhanced intestinal alkaline phosphatase activity, which is known as a key component of intestinal differentiation, through the upregulation of butyric acid. Overall, we demonstrated that LIN28B promotes CRC differentiation through the CDX2/AMACR axis.

Alcohol Metabolism Enriches Squamous Cell Carcinoma Cancer Stem Cells That Survive Oxidative Stress via Autophagy.

BACKGROUND: Alcohol (ethanol) consumption is a major risk factor for head and neck and esophageal squamous cell carcinomas (SCCs). However, how ethanol (EtOH) affects SCC homeostasis is incompletely understood. METHODS: We utilized three-dimensional (3D) organoids and xenograft tumor transplantation models to investigate how EtOH exposure influences intratumoral SCC cell populations including putative cancer stem cells defined by high CD44 expression (CD44H cells). RESULTS: Using 3D organoids generated from SCC cell lines, patient-derived xenograft tumors, and patient biopsies, we found that EtOH is metabolized via alcohol dehydrogenases to induce oxidative stress associated with mitochondrial superoxide generation and mitochondrial depolarization, resulting in apoptosis of the majority of SCC cells within organoids. However, CD44H cells underwent autophagy to negate EtOH-induced mitochondrial dysfunction and apoptosis and were subsequently enriched in organoids and xenograft tumors when exposed to EtOH. Importantly, inhibition of autophagy increased EtOH-mediated apoptosis and reduced CD44H cell enrichment, xenograft tumor growth, and organoid formation rate. CONCLUSIONS: This study provides mechanistic insights into how EtOH may influence SCC cells and establishes autophagy as a potential therapeutic target for the treatment of EtOH-associated SCC.

Patient-derived organoids as a platform for modeling a patient's response to chemoradiotherapy in esophageal cancer.

3D patient-derived organoids (PDOs) have been utilized to evaluate potential therapies for patients with different cancers. However, the use of PDOs created from treatment-naive patient biopsies for prediction of clinical outcomes in patients with esophageal cancer has not yet been reported. Herein we describe a pilot prospective observational study with the goal of determining whether esophageal cancer PDOs created from treatment naive patients can model or predict clinical outcomes. Endoscopic biopsies of treatment-naive patients at a single tertiary care center were used to generate esophageal cancer PDOs, which were treated with standard-of-care chemotherapy, gamma-irradiation, and newer non-standard approaches, such as proton beam therapy or two small molecule inhibitors. Clinical outcomes of patients following neoadjuvant treatment were compared to their in vitro PDO responses, demonstrating the PDO's ability to mirror clinical response, suggesting the value of PDOs in prediction of clinical response to new therapeutic approaches. Future prospective clinical trials should test the use of pre-treatment PDOs to identify specific, targeted therapies for individual patients with esophageal adenocarcinoma.