Identification of a novel histone H2A mono-ubiquitination-inhibiting cell-active small molecule

Histone H2A mono-ubiquitination plays important roles in epigenetic gene expression and is also involved in tumorigenesis. Small molecules controlling H2A ubiquitination are of interest as potential chemical tools and anticancer drugs. To identify novel small molecule inhibitors of H2A ubiquitination, we synthesized and evaluated several compounds designed based on PRT4165 (1), which is a reported histone ubiquitin ligase RING1A inhibitor. We found that compound 11b strongly inhibited the viability and reduced histone H2A mono-ubiquitination in human osteosarcoma U2OS cells. Therefore, compound 11b is a promising lead compound for the development of H2A histone ubiquitination-inhibiting small molecules.

Safety of skipping the tract dilation step for EUS-guided biliary drainage in patients with unresectable malignant biliary obstruction (with video)

BACKGROUND

Thin delivery system stents can be inserted directly without the need for a tract dilation step and are expected to reduce bile leakage during endoscopic ultrasound-guided biliary drainage (EUS-BD). The present study retrospectively compared the safety and efficacy of EUS-BD using a thin metal stent (< 7.5 Fr) with those of EUS-BD using a conventional stent (≥ 7.5 Fr).

METHODS

The present study enrolled 112 patients who underwent EUS-BD using metal stents for unresectable malignant biliary obstruction between April 2016 and July 2022. The primary endpoint was the rate of adverse events (AEs). The secondary endpoints were clinical success rate, procedure time, procedure success rate in the absence of the tract dilation step, recurrent biliary obstruction rate, time to biliary obstruction, and overall survival. Risk factors associated with early AEs were also evaluated.

RESULTS

The rate of early AEs was significantly lower (12% vs. 35%, P = 0.013) and the procedure success without the tract dilation step was significantly higher (82% vs. 33%, P < 0.001) in the thin than in the conventional delivery system stent group. None of the other secondary endpoints differed significantly between the two groups. Multivariate analysis showed that employing the tract dilation step during EUS-BD was a significant independent risk factor for early AEs (skipping vs. employing; HR, 9.66; 95% CI, 1.13-83.0, P = 0.028).

CONCLUSION

Employing the tract dilation step during EUS-BD was a significant risk factor for early AEs. Metal stents with a delivery diameter < 7.5 Fr can be inserted directly without the tract dilation step, resulting in lower early AE rates.

Utility of a partially covered metal stent for salvage sealing therapy for bleeding caused by duodenal invasion of pancreatobiliary cancers: Case series

Pancreatobiliary cancer-related gastrointestinal bleeding caused by duodenal invasion can be a life-threatening condition that is hard to control. It is unclear whether a covered self-expandable metal stent (CSEMS) is useful for hemostasis of bleeding related to advanced pancreatobiliary cancer. The aim of this study was to evaluate the utility of a CSEMS for hemostasis of bleeding caused by duodenal invasion of pancreatobiliary cancer. Between January 2020 and January 2022, seven patients in whom a duodenal CSEMS was inserted to control pancreatobiliary cancer-related bleeding were enrolled. The technical and clinical success rates with respect to hemostasis, procedure time, and adverse events were assessed. All patients were inoperable cases (six with pancreatic cancer [five, stage IV; one, stage III]; and one with gallbladder cancer [stage IV]) in whom CSEMs were inserted to treat refractory bleeding caused by cancer invasion. Hemostasis was achieved in all cases (100% [7/7]). The mean procedure time was 17 ± 7.9 min. There were no adverse events, including migration and rebleeding. No rebleeding occurred up until the time of death in any of the cases (mean follow-up period, 73 ± 27 days). Deployment of duodenal CSEMS is a useful salvage therapy for bleeding caused by advanced pancreatobiliary cancer invasion.

Intraductal Papillary Neoplasm of the Bile Duct Treated with Argon Plasma Coagulation via Endoscopic Ultrasound-guided Choledochoduodenostomy

A 93-year-old man presented to our hospital with a fever, abdominal pain, and jaundice. Computed tomography revealed bilateral bile duct dilation, cystic lesions with bile duct communication, and intraluminal solid nodules arising from the bile duct wall. The patient was diagnosed with intraductal papillary neoplasm of the bile duct. Surgery was not performed, considering the patient's age. It was impossible to control cholangitis using conventional endoscopic therapy. We therefore created an access route to the bile duct using endoscopic ultrasound-guided choledochoduodenostomy and inserted a lumen-apposed metal stent. Thereafter, we performed argon plasma coagulation of the tumor in the bile duct, which successfully prevented cholangitis recurrence.

Endoscopic ultrasound-guided hepaticogastrostomy versus choledochoduodenostomy for malignant biliary obstruction: A meta-analysis

Objectives

Endoscopic ultrasound (EUS)-guided biliary drainage encompasses techniques such as EUS-guided hepaticogastrostomy (EUS-HGS) and EUS-guided choledochoduodenostomy (EUS-CDS). This meta-analysis compared the efficacy of EUS-CDS with that of EUS-HGS for the treatment of biliary obstruction.

Methods

A systematic meta-analysis of all relevant articles listed was performed by searching the Cochrane Library, PubMed, and Google Scholar databases. We used random effects or fixed effects models to compare success rates, adverse events, procedure times, and time to recurrent biliary obstruction after EUS-CDS and EUS-HGS.

Results

This meta-analysis included 18 eligible studies. There was no significant difference between EUS-CDS and EUS-HGS with respect to technical success rate (odds ratio [OR] 1.04; 95% confidence interval [CI] 0.62-1.73) and clinical success rate (OR 0.66; 95% CI 0.43-1.04), or with respect to total procedure-related adverse events (OR 1.39; 95% CI 1.00-1.93). Subgroup analysis of adverse events revealed that the rate of recurrent biliary obstruction (RBO) was significantly higher for EUS-HGS (OR 2.95; 95% CI 1.54-5.64). There was no significant difference between the two methods with respect to time to recurrent biliary obstruction (mean difference -11.93 days; 95% CI -47.77-23.91). However, the procedure time was longer for EUS-HGS (mean difference, 3.21 min; 95% CI 1.24-5.19).

Conclusion

EUS-CDS and EUS-HGS are comparable in terms of technical success, clinical success, and rate of adverse events; however, EUS-CDS is superior with respect to procedure time and preventing RBO.

Impact of sarcopenia on recurrent biliary obstruction after EUS-guided biliary drainage in patients with malignant biliary obstruction

BACKGROUND AND AIMS

Sarcopenia is an important prognostic factor for cancer patients. The aim of this study was to assess the ability of sarcopenia to predict recurrent biliary obstruction (RBO) in patients with unresectable cancer after EUS-guided biliary drainage (EUS-BD).

METHODS

The study enrolled 113 patients who underwent EUS-BD using the self-expandable metal stent (SEMS) for unresectable malignant biliary obstruction (MBO) between April 2016 and December 2021 at Wakayama Medical University Hospital. The skeletal muscle index at the third lumbar spine level (L3) was calculated from computed tomography images. We analyzed the cumulative incidence of RBO at 180 days after stent insertion. Univariate and multivariate analyses were performed to identify variables significantly associated with RBO.

RESULTS

Seventy-six patients were assigned to the sarcopenia group, and 37 were assigned to the non-sarcopenia group. The 180-day cumulative incidence of RBO was 11% in the non-sarcopenia group and 29% in the sarcopenia group (p = 0.034). The time to RBO was significantly shorter for the sarcopenia group (p = 0.028; Gray's test). Multivariate analyses identified sarcopenia as an independent prognostic factor for RBO (present vs absent; HR 4.61; 95% CI 1.76-12.10, p = 0.001). The rates of biliary sludge/food impaction were significantly higher in the sarcopenia group for the causes of RBO (p = 0.048). There were no significant differences between the sarcopenia and the non-sarcopenia groups with respect to related EUS-BD adverse events.

CONCLUSION

Sarcopenia is an independent indicator of RBO in patients with MBO who receive EUS-BD with SEMS.

Role of contrast-enhanced harmonic endoscopic ultrasonography (EUS) and EUS elastography in pancreatic lesions

Pancreatic cancers have a poor prognosis, and their incident rates have risen. Endoscopic ultrasonography (EUS) is an efficient and reliable diagnostic modality for pancreatic lesions, providing high spatial resolution. However, while EUS helps to detect minor pancreatic lesions, nearly all solid pancreatic lesions are hypoechoic, which creates difficulty in making differential diagnoses of pancreatic lesions. When diagnosing pancreatic lesions, the performance of image-enhanced EUS techniques is essential, such as EUS elastography or contrast-enhanced harmonic EUS (CH-EUS). CH-EUS diagnosis is based on assessing the vascularity of lesions, whereas tissue elasticity is measured via EUS elastography. Elastography is either strain or shear-wave, depending on the different mechanical properties being evaluated. The usefulness of enhanced EUS techniques is demonstrated in this review for the differential diagnosis of pancreatic lesions, including solid and cystic lesions, and pancreatic cancer staging.

Design, synthesis, and biological evaluation of phenylcyclopropylamine-entinostat conjugates that selectively target cancer cells

Small molecule-based selective cancer cell-targeting can be a desirable anticancer therapeutic strategy. Aiming to discover such small molecules, we previously developed phenylcyclopropylamine (PCPA)-drug conjugates (PDCs) that selectively release anticancer agents in cancer cells where lysine-specific demethylase 1 (LSD1) is overexpressed. In this work, we designed PCPA-entinostat conjugates for selective cancer cell targeting. PCPA-entinostat conjugate 12 with a 4-oxybenzyl group linker released entinostat in the presence of LSD1 in in vitro assays and selectively inhibited the growth of cancer cells in preference to normal cells, suggesting the potential of PCPA-entinostat conjugates as novel anticancer drug delivery small molecules.

Structural optimization of a lysine demethylase 5 inhibitor for improvement of its cellular activity

Lysine demethylase 5 (KDM5) subfamily proteins are important in epigenetic gene regulation. They are involved in the growth and drug resistance of cancer cells. Therefore, KDM5s are potential cancer therapeutic targets, and their inhibitors hold promise as anti-cancer drugs. Several KDM5 inhibitors, including KDM5-C49 (2a), have exhibited potent KDM5-inhibitory activities in in vitro enzyme assays. However, they do not show enough cellular activity despite being converted to their prodrugs. We hypothesized that their poor lipophilicity should prevent them from sufficiently penetrating the cell membrane, and introducing more lipophilic groups should improve cellular activities. In this study, we investigated 2a and KDM5-C70 (3a), a prodrug of 2a, and attempted to improve its cellular activity by replacing the N,N-dimethyl amino group of 3a with more lipophilic groups. N-Butyl, N-methyl amino compound 2e exhibited potent and selective KDM5-inhibitory activity equal to that of 2a. Furthermore, the cell membrane permeability of 3e, an ethyl ester prodrug of 2e, was six times higher than that of 3a in a parallel artificial membrane permeation assay. In addition, western blot analysis indicated that treating human lung cancer A549 cells with 3e increased histone methylation levels more strongly than that with 3a. Thus, we identified compound 3e as a more cell-active KDM5 inhibitor that has sufficient cell membrane permeability.

Protocol for a Multi-Center Confirmatory Trial to Evaluate the Differential Diagnostic Performance of Contrast-Enhanced Ultrasonography Using Perflubutane in Patients with a Pancreatic Mass: A Multicenter Prospective Study

For pancreatic masses, an evaluation of their vascularity using contrast-enhanced ultrasonography can help improve their characterization. This study was designed to evaluate the utility and safety of contrast-enhanced transabdominal ultrasonography (CE-TUS) and endoscopic ultrasonography (CE-EUS) in the diagnosis of pancreatic masses including solid or cystic masses. This multi-center comparative open-label superiority study is designed to compare Plain (P)-TUS/EUS alone with P-TUS/P-EUS plus CE-TUS/CE-EUS. Three hundred and one patients with a total of 232 solid pancreatic masses and 69 cystic masses were prospectively enrolled. The primary endpoints are to compare the diagnostic accuracy between P-TUS/P-EUS alone and P-TUS/P-EUS plus CE-TUS/CE-EUS for both the TUS and EUS of solid pancreatic masses, and to compare the diagnostic accuracy between P-EUS alone and P-EUS plus CE-EUS in cystic pancreatic masses. The secondary endpoints are to compare the diagnostic sensitivity and specificity of P-TUS/P-EUS alone and P-TUS/P-EUS plus CE-TUS/CE-EUS for pancreatic solid/cystic masses, and the accuracy of P-TUS alone and P-TUS plus CE-TUS for pancreatic cystic masses. Other secondary endpoints included comparing the diagnostic sensitivity, specificity, and accuracy of CE-TUS, CE-EUS and CE-computed tomography (CT) for solid/cystic pancreatic masses. The safety, degree of effective enhancement, and diagnostic confidence obtained with CE-TUS/CE-EUS will also be assessed.

Identification of a Histone Deacetylase 8 Inhibitor through Drug Screenings Based on Machine Learning

Histone deacetylase 8 (HDAC8) is a zinc-dependent HDAC that catalyzes the deacetylation of nonhistone proteins. It is involved in cancer development and HDAC8 inhibitors are promising candidates as anticancer agents. However, most reported HDAC8 inhibitors contain a hydroxamic acid moiety, which often causes mutagenicity. Therefore, we used machine learning for drug screening and attempted to identify non-hydroxamic acids as HDAC8 inhibitors. In this study, we established a prediction model based on the random forest (RF) algorithm for screening HDAC8 inhibitors because it exhibited the best predictive accuracy in the training dataset, including data generated by the synthetic minority over-sampling technique (SMOTE). Using the trained RF-SMOTE model, we screened the Osaka University library for compounds and selected 50 virtual hits. However, the 50 hits in the first screening did not show HDAC8-inhibitory activity. In the second screening, using the RF-SMOTE model, which was established by retraining the dataset including 50 inactive compounds, we identified non-hydroxamic acid 12 as an HDAC8 inhibitor with an IC50 of 842 nM. Interestingly, its IC50 values for HDAC1 and HDAC3-inhibitory activity were 38 and 12 µM, respectively, showing that compound 12 has high HDAC8 selectivity. Using machine learning, we expanded the chemical space for HDAC8 inhibitors and identified non-hydroxamic acid 12 as a novel HDAC8 selective inhibitor.

A Structure-Activity Relationship Study of SNAIL1 Peptides as Inhibitors of Lysine-Specific Demethylase 1

Peptides have recently garnered attention as middle-molecular-weight drugs with the characteristics of small molecules and macromolecules. Lysine-specific demethylase 1 (LSD1) is a potential therapeutic target for lung cancer, neuroblastoma, and leukemia, and some peptide-based LSD1 inhibitors designed based on the N-terminus of SNAIL1, a member of the SNAIL/SCRATCH family of transcription factors, have been reported. The N-terminus of SNAIL1 peptide acts as a cap of the catalytic site of LSD1, inhibiting interactions with LSD1. However, the structure-activity relationship (SAR) of these inhibitors is not yet fully understood. Therefore, in the present study, we aimed to uncover the SAR and to identify novel SNAIL1 peptide-based LSD1 inhibitors. We synthesized peptide inhibitor candidates based on truncating the N-terminus of SNAIL1 or substituting its amino acid residues. In the truncation study, we found that SNAIL1 1-16 (2), which was composed of 16 residues, strongly inhibited LSD1. Furthermore, we investigated the SAR at residues-3 and -5 from the N-terminus and found that peptides 2j and 2k, in which leucine 5 of the parent peptide is substituted with unnatural amino acids, cyclohexylalanine and norleucine, respectively, strongly inhibited LSD1. This result suggests that the hydrophobic interaction between the inhibitor peptides and LSD1 affects the LSD1-inhibitory activity. We believe that this SAR information provides a basis for the development of more potent LSD1 inhibitors.

Utility of contrast-enhanced harmonic endoscopic ultrasonography for prediction of pathological response after neoadjuvant chemotherapy in patients with pancreatic cancer

OBJECTIVES

Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) plays an important role in the diagnosis of pancreatic lesions. The aim of this study was to evaluate whether CH-EUS is useful for predicting the treatment efficacy of neoadjuvant chemotherapy (NAC) determined by pathological response.

METHODS

Patients who underwent CH-EUS before chemotherapy and surgical resection were divided into two groups according to poor (group-P) or rich tumor vascularity (group-R) determined by enhancement pattern on early- and late-phase CH-EUS. The pathological response to chemotherapy was categorized according to Evans' classification. Pathological analysis showing tumor cell destruction (>50 %) defined a good response.

RESULTS

Early-phase CH-EUS classified 44 patients into group-R and 50 into group-P, whereas late-phase CH-EUS classified 10 into group-R and 84 into group-P. Early-phase CH-EUS classification resulted in significantly higher numbers of patients with a good response in the rich group (n = 19) than in the poor group (n = 4; P = 0.0015). Multivariate analysis showed that assignment to the rich group was the strongest independent factor associated with chemosensitivity (P = 0.006, hazard ratio = 5.66, 95 % confidence interval: 1.17-19.27). In resectable patients, the enhancement pattern was the only independent factor associated with chemosensitivity (group-P vs. group-R, P = 0.003; HR [95 % CI], 14.59 [1.38-154.38]). Late-phase CH-EUS did not reveal a significant difference between group-P and group-R.

CONCLUSIONS

Evaluation of vascular pattern on CH-EUS could be useful for predicting the efficacy of NAC in patients with pancreatic cancer. The enhancement pattern on CH-EUS could be a one of the useful features for determining NAC indications in resectable pancreatic cancer patients.

Discovery of Selective Histone Deacetylase 1 and 2 Inhibitors: Screening of a Focused Library Constructed by Click Chemistry, Kinetic Binding Analysis, and Biological Evaluation

Histone deacetylase 1 and 2 (HDAC1/2) inhibitors are potentially useful as tools for probing the biological functions of the isoforms and as therapeutic agents for cancer and neurodegenerative disorders. To discover potent and selective inhibitors, we screened a focused library synthesized by using click chemistry and obtained KPZ560 as an HDAC1/2-selective inhibitor. Kinetic binding analysis revealed that KPZ560 inhibits HDAC2 through a two-step slow-binding mechanism. In cellular assays, KPZ560 induced a dose- and time-dependent increase of histone acetylation and showed potent breast cancer cell growth-inhibitory activity. In addition, gene expression analyses suggested that the two-step slow-binding inhibition by KPZ560 regulated the expression of genes associated with cell proliferation and DNA damage. KPZ560 also induced neurite outgrowth of Neuro-2a cells and an increase in the spine density of granule neuron dendrites of mice. The unique two-step slow-binding character of o-aminoanilides such as KPZ560 makes them interesting candidates as therapeutic agents.

Duodenal bleeding outside covered stents identified by selective computed tomography during arteriography that was successfully treated by embolization: A case report

The patient was a man in his 60s who previously underwent placement of covered stents in the duodenum for a duodenal stricture caused by pancreatic cancer invasion. He experienced multiple episodes of hematemesis and hematochezia during hospitalization. Emergency upper and lower gastrointestinal endoscopies were performed but were unable to reveal the bleeding source. Based on these findings, we suspected small intestinal bleeding and emergency angiography was performed for the purpose of hemostasis. Computed tomography during arteriography was performed from the superior mesenteric artery and revealed extravasation outside the covered stents in the descending portion of the duodenum. Angiography of the inferior pancreaticoduodenal artery revealed extravasation in the descending portion of the duodenum, and the inferior pancreaticoduodenal artery was embolized with n-butyl cyanoacrylate. There were no postoperative symptoms indicative of intestinal ischemia or pancreatitis, and there was no rebleeding after embolization. In patients with bleeding outside the duodenal-covered stents, it can be difficult to identify the bleeding source by upper gastrointestinal endoscopy. In this case, selective computed tomography during arteriography and angiography revealed bleeding outside the duodenal-covered stents that was successfully treated by arterial embolization with n-butyl cyanoacrylate.

Novel Technique of Endoscopic Ultrasonography for the Differential Diagnosis of Gallbladder Lesions and Intraductal Papillary Mucinous Neoplasms: A Single-Center Prospective Study

Detective flow imaging endoscopic ultrasonography (DFI-EUS) is an innovative imaging modality that was developed to detect fine vessels and low-velocity blood flow without contrast agents. We evaluate its utility for the differential diagnosis of gallbladder lesions and intraductal papillary mucinous neoplasms (IPMNs). We enrolled patients who underwent DFI-EUS, e-FLOW EUS, and contrast-enhanced EUS for gallbladder lesions or IPMNs. The detection of vessels using DFI-EUS and e-FLOW EUS was compared with that via contrast-enhanced EUS and pathological findings. The vessel pattern was also categorized as regular or irregular. Of the 33 lesions included, there were final diagnoses of 13 IPMNs and 20 gallbladder lesions. DFI-EUS was significantly superior to e-FLOW EUS for discriminating between mural nodules and mucous clots and between solid gallbladder lesions and sludge using the presence or absence of vessel detection in lesions (p = 0.005). An irregular vessel pattern with DFI-EUS was a significant predictor of malignant gallbladder lesions (p = 0.002). DFI-EUS is more sensitive than e-FLOW-EUS for vessel detection and the differential diagnosis of gallbladder lesions and IPMNs. Vessel evaluation using DFI-EUS may be a useful and simple method for differentiating between mural nodules and mucous clots in IPMN, between solid gallbladder lesions and sludge, and between malignant and benign gallbladder lesions.

High-Resolution Detection of Translocation of Oral Bacteria to the Gut

Ectopic enrichment of oral microbes in the gut is a notable alteration in gut microbial balance. These microbes are likely delivered from the oral cavity with saliva and food; however, evidence of oral-gut microbial transmission is insufficient and needs further investigation. In this observational study, we examined 144 pairs of saliva and stool samples collected from community-dwelling adults to verify the oral-gut microbial link and identify the relevant influencing factors on the increased abundance of oral microbes within the gut. The bacterial composition of each sample was determined using PacBio single-molecule long-read sequencing of the full-length 16S ribosomal RNA gene and amplicon sequence variant (ASV) analysis. Although the bacterial compositions of salivary and gut microbiota were distinctly different, at least 1 ASV was shared between salivary and gut microbiota in 72.9% of subjects. Shared ASVs accounted for 0.0% to 63.1% (median 0.14%) of the gut microbiota in each subject and frequently included abundant Streptococcus salivarius and Streptococcus parasanguinis. Their total relative abundance in the gut was significantly higher in older subjects or those with dental plaque accumulation. The gut microbiota with ≥5% of shared ASVs displayed a higher abundance of Streptococcus, Lactobacillus, and Klebsiella and a lower abundance of Faecalibacterium, Blautia, Megamonas, and Parabacteroides. Our study presents evidence for the translocation of oral bacteria to the gut in community-dwelling adults and suggests that aging and dental plaque accumulation contribute to an increased abundance of oral microbes in the gut, which might be relevant to the compositional shift in the gut commensals.

Comments on and Illustrations of the EFSUMB CEUS Guidelines: Transabdominal and Endoscopic Ultrasound Features of Intrapancreatic Metastases and the Role of Multiparametric Imaging and EUS-Guided Sampling in Rare Pancreatic Tumors

A definite pathologic diagnosis of intrapancreatic metastasis is crucial for the management decision, i.e., curative or palliative surgery versus chemotherapy or conservative/palliative therapy. This review focuses on the appearance of intrapancreatic metastases on native and contrast-enhanced transabdominal ultrasound and endoscopic ultrasound. Differences and similarities in relation to the primary tumor, and the differential diagnosis from pancreatic carcinoma and neuroendocrine neoplasms are described. The frequency of intrapancreatic metastases in autopsy studies and surgical resection studies will be discussed. Further emphasis is placed on endoscopic ultrasound-guided sampling to confirm the diagnosis.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Uncovered versus covered expandable metal stents for malignant gastric outlet obstruction caused by intrinsic and extrinsic tumors: meta-analysis and meta-regression analysis

BACKGROUND AND AIMS

Malignant gastric outlet obstruction (GOO) can be palliated by endoscopic placement of self-expandable metal stents (SEMSs). Studies comparing uncovered (USEMSs) and covered (CSEMSs) SEMSs have yielded inconclusive results. This meta-analysis compared USEMSs with CSEMSs in patients with GOO caused by intrinsic and extrinsic tumors.

METHODS

Potentially relevant articles were identified by searching PubMed, the Cochrane Library, and Medline. The primary outcome was stent dysfunction. Relationships between characteristics of tumors causing GOO and the stent dysfunction rate following USEMSs and CSEMS placement were assessed.

RESULTS

Overall, six randomized controlled trials and 12 observational studies, including 2431 patients, were identified. Rate of stent dysfunction did not differ significantly between USEMSs and CSEMSs (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.73-1.25, I² = 44%), but there was heterogeneity. Meta-regression analysis showed that heterogeneity of stent dysfunction was caused by a difference in the ratio of intrinsic-to-extrinsic tumors causing GOO between studies (coefficient, 0.944; 95% CI, 0.30-1.58). Studies were divided into intrinsic and extrinsic tumor groups. Subgroup analysis showed that the stent dysfunction rate did not differ between USEMSs and CSEMSs in the intrinsic tumor group (OR, 1.10; 95% CI, 0.85-1.41; I² = 32%). In the extrinsic tumor group, USEMS was associated with a lower rate of stent dysfunction than CSEMS (OR, 0.64; 95% CI, 0.47-0.87; I² = 25%).

CONCLUSION

USEMS and CSEMS placement generally showed comparable outcomes among patients with GOO. USEMS was more effective than CSEMS for patients with GOO caused by extrinsic tumors.

Cancer-Cell-Selective Targeting by Arylcyclopropylamine-Vorinostat Conjugates

Anticancer drug delivery by small molecules offers a number of advantages over conventional macromolecular drug delivery systems. We previously developed phenylcyclopropylamine (PCPA)-drug conjugates (PDCs) as small-molecule-based drug delivery vehicles for targeting lysine-specific demethylase 1 (LSD1)-overexpressing cancers. In this study, we applied this PDC strategy to the HDAC-inhibitory anticancer agent vorinostat. Among three synthesized PCPA or arylcyclopropylamine (ACPA)-vorinostat conjugates 1, 9, and 32, conjugate 32 with a 4-oxybenzyl linker showed sufficient stability in buffer solutions, potent LSD1 inhibition, efficient LSD1-dependent vorinostat release, and potent and selective antiproliferative activity toward LSD1-expressing human breast cancer and small-cell lung cancer cell lines. These results indicate that the conjugate selectively releases vorinostat in cancer cells. A similar strategy may be applicable to other anticancer drugs.

Usefulness of Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Diagnosis of Malignancy in Intraductal Papillary Mucinous Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) have a wide pathologic spectrum and it can be difficult to diagnose malignancy, including pathological grade. The aim of this study was to evaluate contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for the diagnosis of malignant IPMN and IPMN-associated invasive carcinoma (invasive IPMC). From 5009 patients diagnosed with IPMN at Wakayama medical university between December 2009 and December 2021, 115 patients who underwent contrast-enhanced computed tomography (CE-CT), conventional EUS, CH-EUS, and surgical resection were enrolled. The detection of mural lesions was compared with pathological findings. Malignant IPMN and invasive IPMC were also assessed according to mural lesion size and vascularity on CH-EUS. CH-EUS and conventional EUS showed significantly higher accuracy than CE-CT in the detection of mural nodules (92%, 83%, and 72%, respectively) and diagnosis of malignant IPMN (75%, 73%, and 63%, respectively). An early wash-out pattern on CH-EUS was observed in significantly more patients with invasive IPMC than in those with low-, intermediate-, or high-grade dysplasia. When compared with CE-CT, CH-EUS was significantly more accurate for detecting mural nodules and more useful for diagnosing malignant IPMN. The vascular pattern on CH-EUS was also useful for diagnosing invasive IPMC.

Covered versus uncovered metal stent for endoscopic drainage of a malignant distal biliary obstruction: Meta-analysis

OBJECTIVES

The role of a covered vs. an uncovered self-expandable metal stent (SEMS) for malignant distal biliary obstruction (MDBO) is not clear. This meta-analysis compared the efficacy of covered vs. uncovered SEMS for patients with MDBO after endoscopic insertion.

METHODS

A systematic meta-analysis of all relevant articles listed in PubMed, the Cochrane Library, and Google Scholar databases was performed. Fixed effects or random effects models were used to investigate pooled effects with 95% confidence intervals (CIs).

RESULTS

The meta-analysis included 2358 patients from 12 eligible studies. Time to recurrent biliary obstruction (RBO) was significantly longer for covered SEMS (mean difference, 45.51 days; 95% CI 11.79-79.24). Although there was no significant difference in the RBO rate, subgroup analysis in pancreatic cancer occupying more than 90% (PC) revealed that the RBO rates were significantly lower for covered SEMS (odds ratio [OR] 0.43, 95% CI 0.25-0.74). Stent migration, sludge formation, and overgrowth were significantly more common with a covered SEMS (OR 7.92, 95% CI 4.01-15.64; OR 3.25, 95% CI 1.89-5.59; OR 2.03, 95% CI 1.20-3.43, respectively). The rate of ingrowth was significantly lower for covered SEMS. There was no significant difference in total procedure-related adverse events between the two types of SEMS.

CONCLUSIONS

A covered SEMS is superior to an uncovered SEMS with respect to prevention of RBO in patients with MDBO, particularly those caused by PC.

P-185 The migration speed of nucleolar precursor bodies in pronuclei affects in vitro fertilization-derived human embryo ploidy status

Study question

Does the migration speed of nucleolar precursor bodies (NPBs) in male and female pronuclei (mPN and fPN) affect in vitro fertilization (IVF)-derived embryo ploidy status?

Summary answer

The NPB migration speed in mPN impacts the IVF-derived human embryo ploidy status and this indicator could be an attractive marker for noninvasive embryo selection.

What is known already

NPBs are not considered as simple nucleolar components transmitted from an oocyte to an embryo, and they could participate in genome remodeling during embryo development. NPBs are essential only shortly after fertilization, suggesting that they may actively participate in centromeric chromatin establishment. A previous study demonstrated that NPBs migrated faster in intracytoplasmic sperm injection-derived zygotes having the potential to develop into a blastocyst and eventually into a baby (Inoue et al., 2021). However, the relationship between NPB migration speed and IVF-derived embryo ploidy status is unclear.

Study design, size, duration

The relationship between the NPB migration speed and embryo ploidy status was retrospectively analyzed in patients with recurrent assisted reproductive technology failure (euploid n =18; aneuploid n =19; and total = 219 NPBs). Archived time-lapse videos (images were recorded every 5 min; Geri+) from incubation after IVF were retrieved after the patients were identified for the study, and the NPB migration speed was analyzed. The retrospective analyses were performed with the patient’s identities masked.

Participants/materials, setting, methods

mPN and fPN were identified by appearance location in a zygote (fPN appearance is just below the polar bodies). The mPN, fPN, and 2–3 NPBs/PN central coordinates were measured by Kinovea (motion capture software). Their central coordinates were confirmed/revised every image and were decided. The migration distance of NPBs between two sequential images was calculated as the standard of the central PN coordinates. Thereafter, the migration speed of NPBs was calculated.

Main results and the role of chance

Both NPB speeds were significantly faster in the euploid than in the aneuploid groups (mPN: 4.08±0.61 vs. 3.54±0.54 µm/h, P =0.003, power [1-β]: 0.999, fPN: 4.03±0.89 vs. 3.26±0.45 µm/h, P &lt;0.003, 1-β: 0.987). The NPB speed in mPN was correlated with that in fPN (rs =0.523, P =0.001). The ploidy status was related to the NPB speeds in mPN and fPN (P &lt;0.05) in univariate logistic analysis including male/female ages, ICM/TE grades, and 29 morphokinetic parameters. The factors associated with ploidy status were the NPB speed in mPN (odds ratio [OR], 10.2; 95% confidence interval [CI], 1.90–54.90; P =0.007) and female age (OR, 0.8; 95%CI, 0.64–0.98; P =0.03) in multivariate logistic analysis. The cutoff value for the NPB speeds in mPN and fPN were 3.65 μm/h (specificity, 73.7%; sensitivity, 77.8%; AUC, 0.78; 95%CI, 0.62–0.93) and 3.77 μm/h (specificity, 89.5%; sensitivity, 66.7%; AUC, 0.78; 95%CI, 0.62–0.94). When the zygotes were categorized by their cutoff values, the euploid rate in zygotes with NPB speeds greater than the cutoff value was significantly higher than that in zygotes with the speeds less than the cutoff value (mPN = 73.7% vs. 22.2% [P =0.003]; fPN = 85.7% vs. 26.1% [P &lt;0.001]).

Limitations, reasons for caution

The NPB migration in the z-axis direction could not be analyzed. NPB tracking could not be performed when NPBs were large in number or drastically moved. Our findings should help in elucidating the relationship, although they did not completely explain the relationship between NPB migration and embryo development.

Wider implications of the findings

The migration speed of NPBs impacts human embryo ploidy status. NPB migration speed may add clinical value for embryo selection, which may be associated with live birth, and consequently, the time of the live birth could be shorter. The indicator could be an attractive marker for noninvasive embryo selection.

Trial registration number

Not applicable

Investigator initiated clinical trial to validate usefulness of specific system for endoscopic ultrasound guided hepaticogastrostomy (HG01) in malignant biliary obstruction (HG01)

INTRODUCTION

Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is a novel drainage option for patients with an inaccessible papilla. Although EUS-HGS has clinical benefits in patients for whom endoscopic retrograde cholangiopancreatography (ERCP) has failed, the rates of adverse events (AEs) associated with EUS-HGS, such as bile peritonitis and stent migration, are higher than for other procedures. The development of a dedicated system for EUS-HGS is therefore desirable to reduce the rate of AEs. We developed a dedicated system for EUS-HGS (HG01 system) which is composed of a 19-gauge needle, 0.025-inch guidewire, a thin delivery system for tract dilation, and an antimigration metal stent. This study is designed to evaluate the efficacy and safety of EUS-HGS using the HG01 system in malignant biliary obstruction.

METHODS/DESIGN

This is a single-arm multicenter prospective study involving 40 patients across six tertiary centers in Japan. Patients with an unresectable malignant biliary obstruction in whom biliary drainage with ERCP failed, is not possible, or is very difficult will be registered in the study. The primary endpoint is the clinical success rate. The secondary endpoints are the technical success rate, procedure-related AE rate, procedure time, procedure success rate using only the HG01 system, stent patency rate, re-intervention success rate, re-intervention method, survival rate, and distance of movement of the stent position.

DISCUSSION

We expect use of the HG01 system to reduce the rate of AEs during EUS-HGS, especially bile leakage and stent migration. If the efficacy and safety of EUS-HGS using the HG01 system is confirmed in the present study, it is likely to be considered the first-choice device for use during EUS-HGS.

How to perform shear wave elastography. Part II

Recently a series of papers was introduced describing on "how to do" certain techniques. More specifically we published on how to perform strain imaging using the transcutaneous and endoscopic ultrasound approach and shear wave elastography (SWE). In the first part we describe how to optimize the examination technique, discussing normal values, pitfalls, artefacts and specific tips for applying SWE to specific organs (liver, breast, thyroid, salivary glands) as part of a diagnostic US examination. In part II, the use of SWE in the pancreas, spleen, kidney, prostate, scrotum, musculoskeletal system, lymph nodes and future developments are discussed.

Contrast-enhanced harmonic endoscopic ultrasonography for predicting the efficacy of first-line gemcitabine and nab-paclitaxel chemotherapy in pancreatic cancer

BACKGROUND AND AIMS

The purpose of this study was to assess prognosis with different intratumoral vascularity on contrast-enhanced endoscopic harmonic ultrasonography (CH-EUS) in pancreatic cancer patients receiving chemotherapy.

METHODS

Patients with unresectable pancreatic cancer who underwent CH-EUS before first-line gemcitabine and nab-paclitaxel (GEM and nab-PTX) therapy were classified into four groups according to vascularity on the early and late phases of contrast enhancement: "Group A″, poor on both phases; "Group B″, rich and poor on the early and late phases, respectively; "Group C″, poor and rich on the early and late phases; "Group D″, rich on both phases. Subgroups were compared in terms of progression-free survival (PFS) and overall survival (OS). We also assessed whether the results with CH-EUS correlate with those of contrast-enhanced computed tomography (CE-CT).

RESULTS

On CH-EUS, 57, 64, 0, and 24 patients were classified into Groups A, B, C, and D, respectively. The median PFS of patients in groups A, B, and D was 3.9, 7.6, and 10.8 months, respectively, and the median OS were 9.5, 13.1, and 18.6 months, respectively. Both PFS and OS were longest in Group D (p < 0.001 and p < 0.001, respectively). The results of CE-CT were consistent with those of CH-EUS, and there was a correlation between CE-CT and CH-EUS.

CONCLUSIONS

Evaluation of intratumoral vascularity by CH-EUS may be useful for predicting the efficacy of chemotherapy in patients with pancreatic cancer. A better response to GEM and nab-PTX can be expected in patients showing rich vascularity at both the early and late phases.

Comparison of endoscopic ultrasonography with and without contrast enhancement for characterization of pancreatic tumors: a meta-analysis

Background and study aims  Endoscopic ultrasonography (EUS) is a reliable and efficient modality for detecting pancreatic tumors; however, plain EUS (P-EUS) is limited with respect to characterization of pancreatic tumors. Recently, the use of contrast-enhanced harmonic EUS (CH-EUS) has increased, and its utility for characterization of pancreatic tumors has been reported. This meta-analysis compares the diagnostic ability of P-EUS with that of CH-EUS for characterization of pancreatic tumors. Methods  A systematic meta-analysis of all potentially relevant articles in PubMed, the Cochrane library, and Google Scholar databases was performed. Fixed effects or random effects models were used to investigate pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio, with 95 % confidence intervals (CIs). Results  This meta-analysis included 719 patients who underwent CH-EUS and 723 who underwent P-EUS, from six eligible studies. The pooled estimates of sensitivity, specificity, and diagnostic odds ratio were 93 % (95 % CI, 0.90-0.95), 80 % (95 % CI, 0.75-0.85), and 57.9 (95 % CI, 25.9-130), respectively, for CH-EUS, and 86 % (95 % CI, 0.82-0.89), 59 % (95 % CI, 0.52-0.65), and 8.3 (95 % CI, 2.8-24.5) for P-EUS. The areas under the summary receiver operating characteristics curves for CH-EUS and P-EUS were 0.96 and 0.80, respectively. The diagnostic odds ratio for pancreatic cancer was 2.98 times higher on CH-EUS than on P-EUS ( P  = 0.03). Funnel plots demonstrated no publication bias. Conclusions  This meta-analysis demonstrates that CH-EUS has higher diagnostic accuracy for pancreatic cancer than P-EUS, and is thus a valuable tool for characterization of pancreatic tumors.

Selective degradation of histone deacetylase 8 mediated by a proteolysis targeting chimera (PROTAC)

We developed a first-in-class proteolysis targeting chimera (PROTAC) for selective degradation of histone deacetylase 8 (HDAC8). The PROTAC induced degradation of HDAC8 without affecting the levels of other HDACs in cellular assays, and inhibited the growth of T-cell leukemia Jurkat cells more potently than a conventional HDAC8 inhibitor.

Impact of sarcopenia on prediction of progression-free survival and overall survival of patients with pancreatic ductal adenocarcinoma receiving first-line gemcitabine and nab-paclitaxel chemotherapy

BACKGROUND AND AIMS

Sarcopenia is an important prognostic factor for cancer patients. Here, we assessed the effects of sarcopenia on progression-free survival (PFS) and overall survival (OS) of patients with pancreatic ductal adenocarcinoma (PDAC) who underwent treatment with first-line gemcitabine and nab-paclitaxel (GEM and nab-PTX).

METHODS

The study enrolled patients with unresectable PDAC who underwent chemotherapy between April 2016 and May 2020. The skeletal muscle index (SMI) at the third lumbar spine level (L3) was calculated from computed tomography (CT) images. Propensity score analysis was used to compare PFS and OS in the sarcopenia and non-sarcopenia groups. Univariate and multivariate analyses were performed to determine variables significantly associated with prognosis.

RESULTS

Of the 176 patients who received first-line GEM and nab-PTX, 84 were selected and divided into two groups of 42 (the sarcopenia and the non-sarcopenia groups) by propensity score matching. The median PFS of the sarcopenia and the non-sarcopenia groups was 5.0 and 8.0 months, respectively (p = 0.004). The median OS was 10.3 and 18.1 months, respectively (p = 0.001). Multivariate analyses revealed that sarcopenia was an independent prognostic factor for PFS and OS (p = 0.004, p = 0.001, respectively). The rates of major grade 3 or 4 AEs were significantly higher in the sarcopenia group (p = 0.008).

CONCLUSIONS

Sarcopenia is an independent indicator of a poor prognosis in patients with PDAC treated with first-line GEM and nab-PTX.

How to perform shear wave elastography. Part I

We recently introduced a series of papers describing how to do certain techniques. This article is the first part of a review of shear wave elastography (SWE). It reports the principles and interpretation of the technique and describes how to optimize it. Normal values, pitfalls and artefacts for the examination of liver, breast. thyroid and salivary gland with shear wave elastography are presented. The manuscript provides specific tips for applying SWE as part of a diagnostic US examination.

Imaging of Fibrosis in Chronic Pancreatitis

Chronic pancreatitis (CP) describes long-standing inflammation of the pancreas, which leads to irreversible and progressive inflammation of the pancreas with fibrosis. CP also leads to abdominal pain, malnutrition, and permanent impairment of exocrine/endocrine functions. However, it is difficult to assess CP pathologically, and imaging modalities therefore play an important role in the diagnosis and assessment of CP. There are four modalities typically used to assess CP. Pancreatic duct features are assessed with magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP). However, ERCP is a rather invasive diagnostic modality for CP, and can result in adverse events such as post-ERCP pancreatitis. Computed tomography (CT) is often the most appropriate initial imaging modality for patients with suspected CP, and has high diagnostic specificity. However, CT findings typically only appear in advanced stages of CP, and it is difficult to detect early CP. Endoscopic ultrasonography (EUS) provides superior spatial resolution compared with other imaging modalities such as CT and magnetic resonance imaging (MRI), and is considered the most reliable and efficient diagnostic modality for pancreatic diseases. The EUS-based Rosemont classification plays an important role in diagnosing CP in clinical practice. Evaluation of tissue stiffness can be another option to assess the diagnosis and progression of CP, and MRI and EUS can be used to assess CP not only with imaging, but also with elasticity measurement. MR and EUS elastography are expected to provide new alternative diagnostic tools for assessment of fibrosis in CP, which is difficult to evaluate pathologically.

Kras Gene Analysis Using Liquid-Based Cytology Specimens Predicts Therapeutic Responses and Prognosis in Patients with Pancreatic Cancer

Simple Summary

New therapeutic strategies are needed to improve the prognosis of pancreatic ductal adenocarcinoma (PDAC) and developing biomarkers that can guide individualized treatment decisions is an important part of these strategies. In this study, we found that unresectable PDAC patients harboring wild-type Kras had significantly longer progression-free survival (PFS) and overall survival (OS) than those harboring mutant Kras after undergoing first-line gemcitabine and nab-paclitaxel (GA) therapy and that wild-type Kras was a significant predictor of longer PFS and OS. This is the first report suggesting that Kras gene analysis has the potential to predict therapeutic responses to GA and the prognosis of unresectable PDAC.

Abstract

Background: Although several molecular analyses have shown that the Kras gene status is related to long-term survival of patients with pancreatic ductal adenocarcinoma (PDAC), the results remain controversial. Here, we examined the Kras gene status in a cohort of unresectable PDAC patients who underwent first-line therapy with gemcitabine and nab-paclitaxel (GA) and assessed differences in chemotherapy responses and survival. Methods: Patients with a histological diagnosis of PDAC (based on EUS-guided fine-needle aspiration) from 2017 to 2019 were enrolled. Tumor genomic DNA was extracted from residual liquid-based cytology specimens and Kras mutations were assessed using the quenching probe method. The relationships between the Kras status and progression-free survival (PFS) and overall survival (OS) were assessed. Results: Of the 110 patients analyzed, 15 had wild-type Kras. Those with the wild-type gene showed significantly longer PFS and OS than those with mutant Kras (6.9/5.3 months (p = 0.044) vs. 19.9/11.8 months (p = 0.037), respectively). Multivariate analyses identified wild-type Kras as a significant independent factor associated with longer PFS and OS (HR = 0.53 (p = 0.045) and HR = 0.35 (p = 0.007), respectively). Conclusions: The analysis of the Kras gene status could be used to predict therapeutic responses to GA and prognosis in unresectable PDAC patients.

Therapeutic efficacy of intra-arterial docetaxel and nedaplatin infusion concomitant with radiotherapy for T4 maxillary sinus squamous cell carcinoma

The aim of this study was to evaluate the efficacy of intra-arterial chemoradiotherapy with docetaxel and nedaplatin for T4 maxillary sinus squamous cell carcinoma (MSSCC). Data were retrospectively analysed for 22 consecutive patients with T4 MSSCC who underwent intra-arterial chemoradiotherapy. Participants received intensity-modulated radiotherapy (70 Gy in 35 fractions) concomitantly with docetaxel (60 mg/m²) and nedaplatin (80 mg/m²) administered every 4 weeks for a total of three sessions. The median follow-up period was 49 months (range 12-91 months). T4a tumours were found in 16 patients (73%) and T4b tumours in six patients (27%). Cervical metastasis was found in nine patients (41%; five N2b, four N2c). The 5-year loco-regional control, disease-free survival, and overall survival rates for patients with T4a disease were 92.3%, 92.3%, and 90.3%, respectively, compared to 83.3% (P = 0.42), 66.7% (P = 0.07), and 83.3% (P = 0.46), respectively, for those with T4b disease. The 5-year loco-regional control, disease-free survival, and overall survival rates for patients with cervical lymph node metastasis were all 87.5% compared to 92.3% (P = 0.86), 84.6% (P = 0.69), and 92.3% (P = 0.93), respectively, for those without cervical metastasis. Intra-arterial chemoradiotherapy with docetaxel and nedaplatin may provide favourable loco-regional control and increased survival in T4 MSSCC.

Value of Low-Mechanical-Index Contrast-Enhanced Transabdominal Ultrasound for Diagnosis of Pancreatic Cancer: A Meta-analysis

The incidence and mortality rates of pancreatic cancer (PC) are increasing. It is important to discriminate PC from the other pancreatic lesions; however, differential diagnosis based on conventional transabdominal ultrasound (US) remains challenging even though US is often the first examination performed. Transabdominal contrast-enhanced ultrasound (CEUS) has high diagnostic accuracy for PC. This meta-analysis aimed to examine the utility of low-mechanical-index CEUS with enhancement for PC diagnosis. A systematic meta-analysis of all potentially relevant articles was performed. Fixed-effects or random-effects models were used to investigate pooled sensitivity, specificity, positive likelihood ratio (LR) and negative LR. The study enrolled 983 patients from nine eligible studies. The pooled estimates of sensitivity and specificity were 92% (95% confidence interval [CI]: 0.89-0.94) and 76% (95% CI: 0.71-0.81), respectively. The diagnostic odds ratio (DOR) for CEUS was high (53.62). The area under the summary receiver operating characteristic curve was 0.95. Funnel plots revealed no publication bias, and there was no significant relationship between the DORs and study characteristics, including continent, type of contrast agent, contrast agent dosage and scan phase. Only number of patients affected diagnostic ability. This meta-analysis indicates that CEUS with enhancement pattern is useful for diagnosis of PC.

Value of contrast-enhanced harmonic endoscopic ultrasound for diagnosing hepatic metastases of pancreatic cancer: A prospective study

BACKGROUND AND AIMS

This study aimed to compare contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) with fundamental B-mode endoscopic ultrasonography (EUS) and contrast-enhanced computed tomography (CE-CT) for the diagnosis of left hepatic lobe metastases of pancreatic adenocarcinoma.

METHODS

In this single-center prospective study, CE-CT, EUS, and CH-EUS were performed to detect left hepatic lobe metastases in patients with pancreatic adenocarcinoma, and the detection rates were compared between EUS plus CH-EUS and the other two modalities. Subgroup comparisons of between-modality detection rate were performed in patients with only metastases of <10 mm. The number of pancreatic adenocarcinoma patients whose clinical stage and treatment strategy were changed because of EUS plus CH-EUS findings was also assessed.

RESULTS

Thirty-one patients were diagnosed with left hepatic lobe metastases. For overall detection of left hepatic lobe metastases, EUS plus CH-EUS had significantly higher accuracy (94.3%) than CE-CT (86.7%) and EUS alone (87.6%) (P = 0.021 and P = 0.020, respectively). For detection of left hepatic lobe metastases < 10 mm, EUS plus CH-EUS (93.3%) was significantly superior to CE-CT (84.4%) and EUS alone (85.6%) (P = 0.021 and P = 0.020, respectively). In five of the 11 patients in whom only CH-EUS allowed detection of hepatic metastases, the stage and/or treatment strategy of the pancreatic adenocarcinoma was changed after CH-EUS.

CONCLUSION

This study demonstrated that EUS plus CH-EUS has advantages over CE-CT and EUS alone with regard to the accuracy of detecting left hepatic lobe metastases, particularly small hepatic metastases and accurate staging.

Identification of Potent and Selective Inhibitors of Fat Mass Obesity-Associated Protein Using a Fragment-Merging Approach

Fat mass obesity-associated protein (FTO) is a DNA/RNA demethylase involved in the epigenetic regulation of various genes and is considered a therapeutic target for obesity, cancer, and neurological disorders. Here, we aimed to design novel FTO-selective inhibitors by merging fragments of previously reported FTO inhibitors. Among the synthesized analogues, compound 11b, which merges key fragments of Hz (3) and MA (4), inhibited FTO selectively over alkylation repair homologue 5 (ALKBH5), another DNA/RNA demethylase. Treatment of acute monocytic leukemia NOMO-1 cells with a prodrug of 11b decreased the viability of acute monocytic leukemia cells, increased the level of the FTO substrate N⁶-methyladenosine in mRNA, and induced upregulation of MYC and downregulation of RARA, which are FTO target genes. Thus, Hz (3)/MA (4) hybrid analogues represent an entry into a new class of FTO-selective inhibitors.

Covered self-expandable metal stents versus plastic stents for preoperative biliary drainage in patient receiving neo-adjuvant chemotherapy for borderline resectable pancreatic cancer: Prospective randomized study

OBJECTIVES

This single-center comparative randomized superiority study compared biliary stenting using fully covered self-expandable metal stents (FCSEMS) and biliary stenting using plastic stents (PS) in preoperative biliary drainage of patients with borderline resectable pancreatic cancer (BRPC) who are planned to undergo a single regimen of neo-adjuvant chemotherapy (NAC).

METHODS

Twenty-two patients with BRPC who required preoperative biliary drainage before NAC (Gemcitabine plus Nab-paclitaxel) were randomly assigned 1:1 to the FCSEMS or PS group. The primary endpoint was the rate of stent dysfunction until surgery or tumor progression. Secondary endpoints were stent patency, number of re-interventions, adverse events of endoscopic retrograde biliary drainage (EBD), operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs.

RESULTS

Eleven patients in each of the groups reached the primary endpoint. The FCSEMS group showed a significantly lower rate of stent dysfunction (18.2% vs. 72.8%, P = 0.015), longer stent patency (P = 0.02), and lower number of re-interventions for stent dysfunction (0.27 ± 0.65 vs. 1.27 ± 1.1, P = 0.001) than the PS group. The adverse events of EBD, operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs did not significantly differ between the two groups.

CONCLUSIONS

In patients with BRPC for preoperative biliary drainage, stent dysfunction occurred less frequently with FCSEMSs than with PSs. In addition, FCSEMS and PS provided similar preoperative management of BRPC in terms of the safety of surgery and medical costs. (UMIN ID000030473).

Endoscopic ultrasonography-guided hepaticogastrostomy using a novel laser-cut type partially covered self-expandable metal stent (with video)

Endoscopic ultrasonography (EUS)-guided hepaticogastrostomy (HGS) is of clinical benefit in patients with failed endoscopic retrograde cholangiopancreatography (ERCP). However, some endoscopists are concerned about the potential risk of adverse events. Bile peritonitis due to bile leakage through the fistula is one of the possible adverse events following EUS-HGS. Recently, a novel laser-cut type partially covered self-expandable metal stent (PCSEMS), which is a dedicated stent for EUS-HGS, has become available. This stent has an uncovered part, despite it being a laser-cut type stent, along with a flared end. In addition, it uses a 7-Fr stent delivery. Therefore, tract dilation might not be needed to deploy the stent, which might reduce the incidence of stent migration. In this study, the safety of EUS-HGS using this novel laser-cut type PCSEMS was evaluated by assessing technical success, which was defined as successful stent deployment, and clinical success, which was defined as reduction in serum total bilirubin levels by 50% and resolution of symptoms related to biliary tract obstruction within 2 weeks. Five patients with unresectable malignant biliary obstruction underwent EUS-HGS using the novel stent. Stent deployment was successfully performed without tract dilation in four patients, although tract dilation using a balloon catheter was needed in one patient. Clinical success was obtained in all patients, and adverse events including abdominal pain and bile peritonitis were not observed in any of the patients. EUS-HGS without tract dilation can be safely performed using a novel laser-cut type PCSEMS. A prospective comparative study evaluating this stent versus conventional stents is needed to corroborate our results.

Contrast-enhanced EUS for the characterization of mural nodules within pancreatic cystic neoplasms: systematic review and meta-analysis

BACKGROUND AND AIMS

Pancreatic cystic neoplasms (PCNs) carry a considerable malignancy risk. Along with main duct dilation, the presence of enhanced mural nodules represents a significant risk factor for malignancy. Several articles assessed the role of contrast-enhanced EUS (CE-EUS) for the identification of malignant features in mural nodules. We evaluate the pooled diagnostic performance of CE-EUS for the identification of high-grade dysplasia or invasive carcinoma among mural nodules in PCNs.

METHODS

A systematic review (Medline, PubMed, EMBASE) and meta-analysis were conducted. Subgroup analysis was used to assess the usefulness of a dedicated contrast-harmonic (CH-EUS). The primary outcome was pooled sensitivity for identification of high-grade dysplasia or invasive carcinoma.

RESULTS

Ten studies (532 patients) were included. Pooled sensitivity of CE-EUS was 88.2% (95% confidence interval [CI], 82.7%-92.5%), specificity 79.1% (95% CI, 74.5%-83.3%), and diagnostic accuracy 89.6% (95% CI, 83.4%-95.8%). Eight studies (320 patients) were conducted using CH-EUS: pooled sensitivity increased to 97.0% (95% CI, 92.5%-99.2%), specificity to 90.4% (95% CI, 85.2%-94.2%), and diagnostic accuracy to 95.6% (95% CI, 92.6%-98.7%). At 42% disease prevalence (pretest probability), a positive CH-EUS increased the disease probability to 88%, whereas a negative test decreased the disease probability to 2%. The number needed to diagnose was 1.5 (95% CI, 1.7-1.3) for CE-EUS and just 1.2 (95% CI, 1.3-1.1) for CH-EUS.

CONCLUSIONS

This study provided robust evidence on CE-EUS value for the characterization of mural nodules within PCNs. A dedicated contrast-harmonic mode, namely CH-EUS, provided an increased diagnostic yield in the identification and characterization of malignant mural nodules.

A Novel Endoscopic Ultrasonography Imaging Technique for Depicting Microcirculation in Pancreatobiliary Lesions without the Need for Contrast-Enhancement: A Prospective Exploratory Study

Detective flow imaging endoscopic ultrasonography (DFI-EUS) provides a new method to image and detect fine vessels and low-velocity blood flow without using ultrasound contrast agents. The aim of this study was to evaluate the utility of DFI-EUS for pancreatobiliary lesions and lymph nodes. Between January 2019 and January 2020, 53 patients who underwent DFI-EUS, e-FLOW EUS, and contrast-enhanced EUS were enrolled. The ability of DFI-EUS and e-FLOW EUS to detect vessels was compared with that of contrast-enhanced EUS. This article describes the DFI technique along with our first experience of its use for vascular assessment of pancreatobiliary lesions. Vessels were imaged in 34 pancreatic solid lesions, eight intraductal papillary mucinous neoplasms (IPMNs), seven gall bladder lesions, and four swollen lymph nodes. DFI-EUS (91%) was significantly superior to e-FLOW EUS (53%) with respect to detection of vessels (p < 0.001) and for discrimination of mural nodules from mucous clots in IPMN and gallbladder lesions from sludge (p = 0.046). Thus, DFI-EUS has the potential to become an essential tool for diagnosis and vascular assessment of various diseases.