Corneocyte proteomics: Applications to skin biology and dermatology.

Advances in mass spectrometry-based proteomics now permit analysis of complex cellular structures. Application to epidermis and its appendages (nail plate, hair shaft) has revealed a wealth of information about their protein profiles. The results confirm known site-specific differences in levels of certain keratins and add great depth to our knowledge of site specificity of scores of other proteins, thereby connecting anatomy and pathology. An example is the evident overlap in protein profiles of hair shaft and nail plate, helping rationalize their sharing of certain dystrophic syndromes distinct from epidermis. In addition, interindividual differences in protein level are manifest as would be expected. This approach permits characterization of altered profiles as a result of disease, where the magnitude of perturbation can be quantified and monitored during treatment. Proteomic analysis has also clarified the nature of the isopeptide cross-linked residual insoluble material after vigorous extraction with protein denaturants, nearly intractable to analysis without fragmentation. These structures, including the cross-linked envelope of epidermal corneocytes, are comprised of hundreds of protein constituents, evidence for strengthening the terminal structure complementary to disulphide bonding. Along with other developing technologies, proteomic analysis is anticipated to find use in disease risk stratification, detection, diagnosis and prognosis after the discovery phase and clinical validation.

NK Cells Preferentially Target Tumor Cells with a Cancer Stem Cell Phenotype.

Increasing evidence supports the hypothesis that cancer stem cells (CSCs) are resistant to antiproliferative therapies, able to repopulate tumor bulk, and seed metastasis. NK cells are able to target stem cells as shown by their ability to reject allogeneic hematopoietic stem cells but not solid tissue grafts. Using multiple preclinical models, including NK coculture (autologous and allogeneic) with multiple human cancer cell lines and dissociated primary cancer specimens and NK transfer in NSG mice harboring orthotopic pancreatic cancer xenografts, we assessed CSC viability, CSC frequency, expression of death receptor ligands, and tumor burden. We demonstrate that activated NK cells are capable of preferentially killing CSCs identified by multiple CSC markers (CD24(+)/CD44(+), CD133(+), and aldehyde dehydrogenase(bright)) from a wide variety of human cancer cell lines in vitro and dissociated primary cancer specimens ex vivo. We observed comparable effector function of allogeneic and autologous NK cells. We also observed preferential upregulation of NK activation ligands MICA/B, Fas, and DR5 on CSCs. Blocking studies further implicated an NKG2D-dependent mechanism for NK killing of CSCs. Treatment of orthotopic human pancreatic cancer tumor-bearing NSG mice with activated NK cells led to significant reductions in both intratumoral CSCs and tumor burden. Taken together, these data from multiple preclinical models, including a strong reliance on primary human cancer specimens, provide compelling preclinical evidence that activated NK cells preferentially target cancer cells with a CSC phenotype, highlighting the translational potential of NK immunotherapy as part of a combined modality approach for refractory solid malignancies.

A general approach to high-yield biosynthesis of chimeric RNAs bearing various types of functional small RNAs for broad applications.

RNA research and therapy relies primarily on synthetic RNAs. We employed recombinant RNA technology toward large-scale production of pre-miRNA agents in bacteria, but found the majority of target RNAs were not or negligibly expressed. We thus developed a novel strategy to achieve consistent high-yield biosynthesis of chimeric RNAs carrying various small RNAs (e.g. miRNAs, siRNAs and RNA aptamers), which was based upon an optimal noncoding RNA scaffold (OnRS) derived from tRNA fusion pre-miR-34a (tRNA/mir-34a). Multi-milligrams of chimeric RNAs (e.g. OnRS/miR-124, OnRS/GFP-siRNA, OnRS/Neg (scrambled RNA) and OnRS/MGA (malachite green aptamer)) were readily obtained from 1 l bacterial culture. Deep sequencing analyses revealed that mature miR-124 and target GFP-siRNA were selectively released from chimeric RNAs in human cells. Consequently, OnRS/miR-124 was active in suppressing miR-124 target gene expression and controlling cellular processes, and OnRS/GFP-siRNA was effective in knocking down GFP mRNA levels and fluorescent intensity in ES-2/GFP cells and GFP-transgenic mice. Furthermore, the OnRS/MGA sensor offered a specific strong fluorescence upon binding MG, which was utilized as label-free substrate to accurately determine serum RNase activities in pancreatic cancer patients. These results demonstrate that OnRS-based bioengineering is a common, robust and versatile strategy to assemble various types of small RNAs for broad applications.

Per-oral cholangioscopy in patients with primary sclerosing cholangitis: a 12-month follow-up study.

Background and study aims Patients with primary sclerosing cholangitis (PSC) have a 9% to 20% lifetime incidence of cholangiocarcinoma (CCA). Per-oral cholangioscopy (POCS) added to endoscopic retrograde cholangiography (ERC) could potentially improve detection of CCA occurrence. We prospectively assessed POCS identification of 12-month CCA incidence in PSC patients undergoing ERC. Patients and methods Consecutive patients with PSC, an indication for ERC, and no prior liver transplantation were enrolled. During the index procedure, POCS preceded planned therapeutic maneuvers. The primary endpoint was ability for POCS visualization with POCS-guided biopsy to identify CCA during 12-month follow-up. Secondary endpoints included ability of ERC/cytology to identify CCA, repeat ERC, liver transplantation, and serious adverse events (SAEs). Results Of 42 patients enrolled, 36 with successful cholangioscope advancement were analyzed. Patients had a mean age 43.5±15.6 years and 61% were male. Three patients diagnosed with CCA had POCS visualization impressions of benign/suspicious/suspicious, and respective POCS-guided biopsy findings of suspicious/positive/suspicious for malignancy at the index procedure. The three CCA cases had ERC visualization impressions of benign/benign/suspicious, and respective cytology findings of atypical/atypical/suspicious for malignancy. No additional patients were diagnosed with CCA during median 11.5-month follow-up. Twenty-three repeat ERCs (5 including POCS) were performed in 14 patients. Five patients had liver transplantation, one after CCA diagnosis and four after benign cytology at the index procedure. Three patients (7.1%) had post-ERC pancreatitis. No SAEs were POCS-related. Conclusions In PSC patients, POCS visualization/biopsy and ERC/cytology each identified three cases of CCA. Some patients had a repeat procedure and none experienced POCS-related SAEs.

Role of endoscopic ultrasound for pre-intervention evaluation in early esophageal cancer.

BACKGROUND: Endoscopic ultrasound (EUS) stands as an accurate imaging modality for esophageal cancer staging, however utilization of EUS in early-stage cancer management remains controversial. Identification of non-applicability of endoscopic interventions with deep muscular invasion with EUS in pre-intervention evaluation of early-stage esophageal cancer is compared to endoscopic and histologic indicators. AIM: To display the role of EUS in pre-intervention early esophageal cancer staging and how the index endoscopic features of invasive esophageal malignancy compare for prediction of depth of invasion and cancer management. METHODS: This was a retrospective study of patients who underwent pre-resection EUS after a diagnosis of esophageal cancer at a tertiary medical center from 2012 to 2022. Patient clinical data, initial esophagogastroduodenoscopy/biopsy, EUS, and final resection pathology reports were abstracted, and statistical analysis was conducted to assess the role of EUS in management decisions. RESULTS: Forty nine patients were identified for this study. EUS T stage was concordant with histological T stage in 75.5% of patients. In determining submucosal involvement (T1a vs T1b), EUS had a specificity of 85.0%, sensitivity of 53.9%, and accuracy of 72.7%. Endoscopic features of tumor size > 2 cm and the presence of esophageal ulceration were significantly associated with deep invasion of cancer on histology. EUS affected management from endoscopic mucosal resection/submucosal dissection to esophagectomy in 23.5% of patients without esophageal ulceration and 6.9% of patients with tumor size < 2 cm. In patients without both endoscopic findings, EUS identified deeper cancer and changed management in 4.8% (1/20) of cases. CONCLUSION: EUS was reasonably specific in ruling out submucosal invasion but had relatively poor sensitivity. Data validated endoscopic indicators suggested superficial cancers in the group with a tumor size < 2 cm and the lack of esophageal ulceration. In patients with these findings, EUS rarely identified a deep cancer that warranted a change in management.

Multiregional Sequencing Analysis Reveals Extensive Genetic Heterogeneity in Gastric Tumors from Latinos.

Gastric cancer is a leading cause of cancer mortality and health disparities in Latinos. We evaluated gastric intratumoral heterogeneity using multiregional sequencing of >700 cancer genes in 115 tumor biopsies from 32 patients, 29 who were Latinos. Analyses focused on comparisons with The Cancer Genome Atlas (TCGA) and on mutation clonality, druggability, and signatures. We found that only approximately 30% of all mutations were clonal and that only 61% of the known TCGA gastric cancer drivers harbored clonal mutations. Multiple clonal mutations were found in new candidate gastric cancer drivers such as EYS, FAT4, PCDHA1, RAD50, EXO1, RECQL4, and FSIP2. The genomically stable (GS) molecular subtype, which has the worse prognosis, was identified in 48% of our Latino patients, a fraction that was >2.3-fold higher than in TCGA Asian and White patients. Only a third of all tumors harbored clonal pathogenic mutations in druggable genes, with most (93%) GS tumors lacking actionable clonal mutations. Mutation signature analyses revealed that, in microsatellite-stable (MSS) tumors, DNA repair mutations were common for both tumor initiation and progression, while tobacco, POLE, and inflammation signatures likely initiate carcinogenesis. MSS tumor progression was likely driven by aging- and aflatoxin-associated mutations, as these latter changes were usually nonclonal. In microsatellite-unstable tumors, nonclonal tobacco-associated mutations were common. Our study, therefore, contributed to advancing gastric cancer molecular diagnostics and suggests clonal status is important to understanding gastric tumorigenesis. Our findings of a higher frequency of a poor prognosis associated molecular subtype in Latinos and a possible new aflatoxin gastric cancer etiology also advance cancer disparities research. Significance: Our study contributes to advancing our knowledge of gastric carcinogenesis, diagnostics, and cancer health disparities.

Characterizing the origin of autofluorescence in human esophageal epithelium under ultraviolet excitation.

The autofluorescence under ultraviolet excitation arising from normal squamous and columnar esophageal mucosa is investigated using multispectral microscopy. The results suggest that the autofluorescence signal arises from the superficial tissue layer due to the short penetration depth of the ultraviolet excitation. As a result, visualization of esophageal epithelial cells and their organization can be attained using wide-field autofluorescence microscopy. Our results show tryptophan to be the dominant source of emission under 266 nm excitation, while emission from NADH and collagen are dominant under 355 nm excitation. The analysis of multispectral microscopy images reveals that tryptophan offers the highest image contrast due to its non-uniform distribution in the sub-cellular matrix. This technique can simultaneously provide functional and structural imaging of the microstructure using only the intrinsic tissue fluorophores.

Comprehensive mass spectrometry based metabolic profiling of blood plasma reveals potent discriminatory classifiers of pancreatic cancer.

Poor outcome of pancreatic cancer necessitates development of an early diagnostic method to reduce mortality. No reliable early diagnostic test for pancreatic cancer detection has been developed and validated to date. In the current study, metabolic profiling of plasma samples from selected cancer patients and noncancerous controls was performed to seek novel metabolic biomarkers of pancreatic cancer. A comprehensive mass spectrometry based analytical platform established at the Metabolomics Core of the UC Davis Genome Center allowed detection of multiple compounds previously unreported in plasma from pancreatic cancer patients. It was found that selective amino acids, bile acids, and polar lipids were detected with increased or decreased levels in pancreatic cancer samples compared to controls. These findings on blood plasma levels of the relevant metabolites might be very useful clinical parameters for early diagnosis of pancreatic cancer.

Pharmacophore hybridisation and nanoscale assembly to discover self-delivering lysosomotropic new-chemical entities for cancer therapy.

Integration of the unique advantages of the fields of drug discovery and drug delivery is invaluable for the advancement of drug development. Here we propose a self-delivering one-component new-chemical-entity nanomedicine (ONN) strategy to improve cancer therapy through incorporation of the self-assembly principle into drug design. A lysosomotropic detergent (MSDH) and an autophagy inhibitor (Lys05) are hybridised to develop bisaminoquinoline derivatives that can intrinsically form nanoassemblies. The selected BAQ12 and BAQ13 ONNs are highly effective in inducing lysosomal disruption, lysosomal dysfunction and autophagy blockade and exhibit 30-fold higher antiproliferative activity than hydroxychloroquine used in clinical trials. These single-drug nanoparticles demonstrate excellent pharmacokinetic and toxicological profiles and dramatic antitumour efficacy in vivo. In addition, they are able to encapsulate and deliver additional drugs to tumour sites and are thus promising agents for autophagy inhibition-based combination therapy. Given their transdisciplinary advantages, these BAQ ONNs have enormous potential to improve cancer therapy.

Real-time microscopic imaging of esophageal epithelial disease with autofluorescence under ultraviolet excitation.

Detection of esophageal disease in current clinical practice is limited to visualization of macroscopic epithelial morphology. In this work, we investigate high resolution autofluorescence imaging under ultra violet excitation to visualize microscopic epithelial changes related to disease progression using a bench top prototype microscope. The approach is based on the hypothesis that UV excitation light can only penetrate the superficial layer of cells resulting in autofluorescence images of the epithelial layer without using an additional image sectioning approach. The experiments were performed using ex vivo human esophagus biopsy specimens. The results indicate that cellular morphology information related to disease progression is attainable without tissue preparation.

Eosinophilic cholangitis: A case report of diagnostically challenging eosinophilic infiltrative biliary obstruction.

BACKGROUND: Evaluation of biliary strictures primarily focuses on ruling out malignancy in older age groups. With endoscopic tools such as endoscopic ultrasound (EUS) and cholangioscopy, improved biliary visualization has enhanced the investigation of intraluminal biliary lesions and provided modalities for targeted biopsies. Benign biliary strictures, however, may pose a diagnostic dilemma. CASE SUMMARY: A 71-year-old female with past medial history of hypothyroidism presenting for abnormal biliary imaging. Patient's previous evaluation was concerning for common bile duct dilation with cholelithiasis, for which she underwent a cholecystectomy. Due to persistent symptoms and worsening liver function tests, she presented to our institution for further workup. Subsequently, the patient underwent an EUS and multiple ERCP's with cholangioscopy; biliary biopsies revealed no evidence of malignancy but concerning for prominent eosinophilic infiltration. After further review of multiple pathology specimens and the benign clinical course, we diagnosed the patient with eosinophilic cholangitis. CONCLUSION: Eosinophilic cholangitis is a rare disease and can present as a challenging case diagnostically. This case raises the potential utility of quantitative eosinophilic infiltration reporting in creating an objective diagnostic metric for eosinophilic cholangitis.

Comparison of Endoscopic Ultrasound Biopsy Needles for Endoscopic Ultrasound-Guided Liver Biopsy.

BACKGROUND/AIMS: To compare the performance of latest commercially available endoscopic ultrasound biopsy needles. METHODS: Six latest commercially available needles were tested on a freshly harvested bovine liver; the tested needles included three 19 G, one 20 G, and two 22 G needles. Five biopsies were performed per needle with 10 mL of wet suction. The primary outcome was the number of complete portal tracts (CPTs) per needle aspirate. The secondary outcomes were the mean specimen length and mean fragment length. Analysis of variance and Tukey's test were applied. RESULTS: All 19 G needles and the 20 G needle yielded similar mean CPTs and were superior to the SharkCore 22 G needle (p<0.001 adjusted for multiplicity). There was no statistically significant difference in total specimen length among the three 19 G needles and the 20 G needle tested. The two 22 G needles performed similarly with respect to the number of CPTs, mean fragment length, and mean specimen length (adjusted p=0.07, p=0.59, and p=0.10, respectively). CONCLUSION: The specimen adequacy was similar among the 3 latest commercially available 19 G needles. The endoscopist may choose a larger-bore needle based on availability without concerns of specimen adequacy. Further studies are needed to assess the ease of needle use in various anatomical locations and to confirm the optimal needle design.

Circumferential ablation of Barrett's esophagus that contains high-grade dysplasia: a U.S. Multicenter Registry.

BACKGROUND: The management strategies for Barrett's esophagus (BE) that contains high-grade dysplasia (HGD) include intensive endoscopic surveillance, photodynamic therapy, thermal ablation, EMR, and esophagectomy. OBJECTIVE: To assess the safety and effectiveness of endoscopic circumferential balloon-based ablation by using radiofrequency energy for treating BE HGD. DESIGN: Multicenter U.S. registry. SETTING: Sixteen academic and community centers; treatment period from September 2004 to March 2007. PATIENTS: Patients with histologic evidence of intestinal metaplasia (IM) that contained HGD confirmed by at least 2 expert pathologists. A prior EMR was permitted, provided that residual HGD remained in the BE region for ablation. INTERVENTION: Endoscopic circumferential ablation with follow-up esophageal biopsies to assess the histologic response to treatment. OUTCOMES: Histologic complete response (CR) end points: (1) all biopsy specimen fragments obtained at the last biopsy session were negative for HGD (CR-HGD), (2) all biopsy specimens were negative for any dysplasia (CR-D), and (3) all biopsy specimens were negative for IM (CR-IM). RESULTS: A total of 142 patients (median age 66 years, interquartile range [IQR] 59-75 years) who had BE HGD (median length 6 cm, IQR 3-8 cm) underwent circumferential ablation (median 1 session, IQR 1-2). No serious adverse events were reported. There was 1 asymptomatic stricture and no buried glands. Ninety-two patients had at least 1 follow-up biopsy session (median follow-up 12 months, IQR 8-15 months). A CR-HGD was achieved in 90.2% of patients, CR-D in 80.4%, and CR-IM in 54.3%. LIMITATIONS: A nonrandomized study design, without a control arm, a lack of centralized pathology review, ablation and biopsy technique not standardized, and a relatively short-term follow-up. CONCLUSIONS: Endoscopic circumferential ablation is a promising modality for the treatment of BE that contains HGD. In this multicenter registry, the intervention safely achieved a CR for HGD in 90.2% of patients at a median of 12 months of follow-up.

Multimodal near infrared spectral imaging as an exploratory tool for dysplastic esophageal lesion identification.

We explore nine different combinations of fluorescence, light scattering, and polarization spectral imaging approaches in the near-infrare spectral region toward the diagnosis of pathologic and normal esophageal lesions. The combinations of all the imaging techniques were evaluated for maximal sensitivity and specificity. The results suggest that this multimodal approach is capable of highly accurate detection of the presence of pathologic tissue.

Endoscopic ultrasound-guided celiac plexus neurolysis for pancreatic cancer pain: a single-institution experience and review of the literature.

Pancreatic cancer is a common gastrointestinal malignancy with a poor prognosis. The primary goal for caregivers is effective palliative care, especially pain control, which is routinely managed by administration of narcotic analgesics. An alternative or adjunctive modality is celiac plexus neurolysis (CPN), a safe and effective procedure. Recent advances in the use of endoscopic ultrasonography (EUS) have made it an attractive guidance technique for CPN while allowing for a simultaneous tissue diagnosis. We report our experience using EUS-guided CPN and review the available literature regarding this modality.

Immunoisolation of pancreatic epithelial cells from endoscopic ultrasound-guided fine needle aspirates with magnetic beads for downstream molecular application.

BACKGROUND: Evaluation of pancreatic mass is routinely performed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). However, molecular analyses of the tumor cells on FNA samples are limited by the significant cellular heterogeneity. The goal of the current study is to evaluate a magnetic immunoconcentration technique in isolating pancreatic epithelial cells from needle aspirates, and to demonstrate that the isolated cells could be utilized for molecular analysis. METHODS: Pancreatic EUS-FNA specimens were processed and stored at -80°C. Based on the cytopathological diagnosis, 17 adenocarcinoma, 3 lymphoproliferative, and 3 benign cases were retrieved from the collection for further analyses. Epithelial cells were isolated using antihuman epithelial cell specific antibody-bound magnetic beads, and the isolated cellular component was confirmed cytologically. Genomic DNA was extracted, quantitated, and evaluated with methylation-specific PCR for cyclin D2 in 8 adenocarcinoma cases. RESULTS: After optimization, malignant epithelial cells were successfully isolated from all adenocarcinoma cases. Normal pancreatic ductal cells were isolated from three benign cases. No cells were retrieved after immunomagnetic isolation in all three lymphoproliferative cases. DNA yields were 5-2646 ng, with a mean of 357 ng. Methylation-specific PCR for cyclin D2 on the 8 carcinoma cases showed methylated state at the promoter region, demonstrating feasible evaluation of the methylation status. CONCLUSION: The magnetic immunoconcentration of pancreatic EUS-FNA specimen described here is a practical method of isolating pancreatic epithelial cells from needle aspirates. Isolated cells were sufficient for performing subsequent molecular analysis.

Pancreatic cancer early detection: expanding higher-risk group with clinical and metabolomics parameters.

Pancreatic ductal adenocarcinoma (PDAC) is the fourth and fifth leading cause of cancer death for each gender in developed countries. With lack of effective treatment and screening scheme available for the general population, the mortality rate is expected to increase over the next several decades in contrast to the other major malignancies such as lung, breast, prostate and colorectal cancers. Endoscopic ultrasound, with its highest level of detection capacity of smaller pancreatic lesions, is the commonly employed and preferred clinical imaging-based PDAC detection method. Various molecular biomarkers have been investigated for characterization of the disease, but none are shown to be useful or validated for clinical utilization for early detection. As seen from studies of a small subset of familial or genetically high-risk PDAC groups, the higher yield and utility of imaging-based screening methods are demonstrated for these groups. Multiple recent studies on the unique cancer metabolism including PDAC, demonstrate the potential for utility of the metabolites as the discriminant markers for this disease. In order to generate an early PDAC detection screening strategy available for a wider population, we propose to expand the population of higher risk PDAC group with combination clinical and metabolomics parameters.

Utility of serum CA19-9 levels in the diagnosis of pancreatic ductal adenocarcinoma in an endoscopic ultrasound referral population.

PURPOSE: Recent data suggest the use of carbohydrate antigen (CA) 19-9 as a potential marker in the early detection of pancreatic ductal adenocarcinoma (PDAC) when used in the appropriate clinical setting. Here, we assess the utility of CA19-9 in PDAC detection in a select population of pancreatic endoscopic ultrasound (EUS) referrals. METHODS: Retrospective review of an institutional EUS Pancreas Registry containing cases referred from November 2002 to November 2011 was completed for categorical analyses with CA19-9 level. A separate case-control study for the subset of non-elevated CA19-9 PDAC population was also performed to characterize the clinical features in this unique group of patients. RESULTS: Two hundred eighty-three patients had available CA19-9 data in the registry and were included in the study. Compared to the typical PDAC distribution, the proportion of patients with stage I disease was significantly higher in our registry population (P < 0.0001). Elevated CA19-9 levels most often reflected a diagnosis of PDAC relative to other pancreaticobiliary diagnoses. However, we observed that 15 % of patients with PDAC had normal CA19-9 levels. Clinical characteristics for this false-negative PDAC group compared to the true-positive group demonstrated a predilection for detection of cancer in the body/tail of the pancreas (P = 0.03), increased likelihood of lymph node metastases (P = 0.03), and initial presentation with vague abdominal pain or pancreatic mass as an incidental finding on imaging studies (P = 0.01). CONCLUSIONS: Elevated CA19-9 demonstrated a greater likelihood of PDAC diagnosis relative to benign pancreatic pathology, and higher levels of CA19-9 were in line with worse PDAC stage. Patients with normal CA19-9 PDAC may represent a unique subclass of patients, presenting with atypical clinical features, and possibly more advanced stage disease at the time of diagnosis. These patients may benefit from more diligent EUS examination or perhaps closer follow-up management.