Identification of α-Tocopherol succinate as an RFFL-substrate interaction inhibitor inducing peripheral CFTR stabilization and apoptosis.

The E3 ubiquitin ligase RFFL is an apoptotic inhibitor highly expressed in cancers and its knockdown suppresses cancer cell growth and sensitizes to chemotherapy. RFFL also participates in peripheral protein quality control which removes the functional cell surface ΔF508-CFTR channel and reduces the efficacy of pharmaceutical therapy for cystic fibrosis (CF). Although RFFL inhibitors have therapeutic potential for both cancer and CF, they remain undiscovered. Here, a chemical array screening has identified α-tocopherol succinate (αTOS) as an RFFL ligand. NMR analysis revealed that αTOS directly binds to RFFL's substrate-binding region without affecting the E3 enzymatic activity. Consequently, αTOS inhibits the RFFL-substrate interaction, ΔF508-CFTR ubiquitination and elimination from the plasma membrane of epithelial cells, resulting in the increased functional CFTR channel. Among the α-tocopherol (αTOL) analogs we tested, only αTOS inhibited the RFFL-substrate interaction and increased the cell surface ΔF508-CFTR, depending on RFFL expression. Similarly, the unique proapoptotic effect of αTOS was dependent on RFFL expression. Thus, unlike other αTOL analogs, αTOS acts as an RFFL protein-protein interaction inhibitor which may explain its unique biological properties among αTOL analogs. Moreover, αTOS may act as a CFTR stabilizer, a novel class of drugs that extend cell surface ΔF508-CFTR lifetime.

The risk of weekend biopsy: Impact of specimen source and fixation status on HER2 assessment in the treatment of advanced gastric cancer (The HER_WEEKEND study).

Accurate evaluation of human epidermal growth factor receptor type 2 (HER2) expression is crucial for determining chemotherapy regimens in gastric cancer. However, formalin fixation status has been identified as an important factor affecting HER2 assessment reliability. This retrospective cohort study aimed to investigate the correlation between sample collection day (weekday vs. weekend) and source (biopsy vs. surgical specimens) in assessing HER2 expression in patients with unresectable advanced/recurrent gastric cancer. Data were collected from gastric cancer patients who received chemotherapy at a single public hospital in Japan from 2008 to 2021. The analysis included 177 patients (109 men, 68 women) with a median age of 68.0 (21-88) years, and the primary outcome was the HER2 positivity rate. The overall HER2 positivity rate was 18.1%, with higher rates on weekdays (20.0%) compared to weekends (12.8%). Biopsies had higher positivity rates on weekdays (23.9%) but lower rates on weekends (11.1%) than surgical specimens. Significant differences were observed in formalin fixation times between weekdays and weekends for both biopsies and surgical samples. The study findings suggest that longer formalin fixation times on weekends may lead to underestimating HER2 expression, particularly in biopsies. Therefore, it is crucial to be cautious of excessive formalin fixation when collecting samples, especially during weekend biopsies.

Improvement of detection sensitivity of upper gastrointestinal epithelial neoplasia in linked color imaging based on data of eye tracking.

BACKGROUND AND AIM: Linked color imaging (LCI) is useful for screening in the gastrointestinal tract; however, its true clinical benefit has not been determined. The aim of this study was to determine the objective advantage of LCI for detection of upper gastrointestinal neoplasms. METHODS: Nine endoscopists, including three novices, three trainees, and three experts, prospectively performed eye tracking. From 30 cases of esophageal or gastric neoplasm and 30 normal cases without neoplasms, a total of 120 images, including 60 pair images of white light imaging (WLI) and LCI taken at the same positions and angles, were randomly shown for 10 s. The sensitivity of tumor detection as a primary endpoint was evaluated and sensitivities by organ, size, and visual gaze pattern were also assessed. Color differences (ΔE using CIE1976 [L*a*b*]) between lesions and surrounding mucosa were measured and compared with detectability. RESULTS: A total of 1080 experiments were completed. The sensitivities of tumor detection in WLI and LCI were 53.7% (50.1-56.8%) and 68.1% (64.8-70.8%), respectively (P = 0.002). LCI provided higher sensitivity than WLI for the novice and trainee groups (novice: 42.2% [WLI] vs 65.6% [LCI], P = 0.003; trainee: 54.4% vs 70.0%, P = 0.045). No significant correlations were found between sensitivity and visual gaze patterns. LCI significantly increased ΔE, and the diagnostic accuracy with WLI depended on ΔE. CONCLUSIONS: In conclusion, LCI significantly improved sensitivity in the detection of epithelial neoplasia and enabled epithelial neoplasia detection that is not possible with the small color difference in WLI. (UMIN000047944).

An Autopsy Case of Rapidly Aggravated Clostridium perfringens Septicemia with Colorectal Cancer.

This report presents a case of a 60-year-old man who was diagnosed with ascending colon cancer with metastases of the lymph nodes and multiple liver metastases. Three days before the introduction of the first chemotherapy, he visited our hospital due to high fever. The blood test revealed an increase in the inflammatory response, hepatobiliary enzyme level, lactate dehydrogenase (LDH) level, and renal function deterioration. Contrast-enhanced computed tomography (CT) showed a rapid progression of primary lesion and liver metastatic lesions. Treatment with 5-fluorouracil, leucovorin, and oxaliplatin and cetuximab (FOLFOX/Cmab) was initiated, and the patient was admitted to our hospital after the first day of chemotherapy. At midnight, he had chills, red urine, and rapid hypoxemia. The second blood test showed progression of anemia; increased total bilirubin, aspartate aminotransferase, and LDH levels; and decreased platelet and fibrinogen levels. The serum was red wine in color, indicating marked hemolysis. The respiratory condition rapidly deteriorated, and tracheal intubation was performed and transferred into the intensive care unit. However, blood oxygenation did not increase, and the patient died the next morning, 19 h after admission, despite intensive care. Postmortem CT showed intraperitoneal free air and gas retention in the liver tumor and portal vein system. Pathological autopsy revealed perforation in ascending colon cancer, many Gram-positive rods in the perforation site, dissemination of bacteria throughout the body, and diffuse pulmonary edema. Subsequently, blood cultures reported Clostridium perfringens (CP), which is a product of alpha-toxin. CP infection can cause rapid aggravation and sudden death. The physicians should be aware of this highly fatal infection, leading to immediate diagnosis and treatment.

The Ubiquitin Ligase RNF34 Participates in the Peripheral Quality Control of CFTR (RNF34 Role in CFTR PeriQC).

The peripheral protein quality control (periQC) system eliminates the conformationally defective cystic fibrosis transmembrane conductance regulator (CFTR), including ∆F508-CFTR, from the plasma membrane (PM) and limits the efficacy of pharmacological therapy for cystic fibrosis (CF). The ubiquitin (Ub) ligase RFFL is responsible for the chaperone-independent ubiquitination and lysosomal degradation of CFTR in the periQC. Here, we report that the Ub ligase RNF34 participates in the CFTR periQC in parallel to RFFL. An in vitro study reveals that RNF34 directly recognizes the CFTR NBD1 and selectively promotes the ubiquitination of unfolded proteins. RNF34 was localized in the cytoplasm and endosomes, where RFFL was equally colocalized. RNF34 ablation increased the PM density as well as the mature form of ∆F508-CFTR rescued at low temperatures. RFFL ablation, with the exception of RNF34 ablation, increased the functional PM expression of ∆F508-CFTR upon a triple combination of CFTR modulators (Trikafta) treatment by inhibiting the K63-linked polyubiquitination. Interestingly, simultaneous ablation of RNF34 and RFFL dramatically increased the functional PM ∆F508-CFTR by inhibiting the ubiquitination in the post-Golgi compartments. The CFTR-NLuc assay demonstrates that simultaneous ablation of RNF34 and RFFL dramatically inhibits the degradation of mature ∆F508-CFTR after Trikafta treatment. Therefore, these results suggest that RNF34 plays a crucial role in the CFTR periQC, especially when there is insufficient RFFL. We propose that simultaneous inhibition of RFFL and RNF34 may improve the efficacy of CFTR modulators.

Incidence of cancer-associated thromboembolism in Japanese gastric and colorectal cancer patients receiving chemotherapy: a single-institutional retrospective cohort analysis (Sapporo CAT study).

OBJECTIVE: Few data regarding the incidence of cancer-associated thromboembolism (TE) are available for Asian populations. We investigated the incidence of TE (TEi) and its risk factors among gastric and colorectal cancer (GCC) patients received chemotherapy in a daily practice setting. DESIGN: A retrospective cohort study. SETTING: A single-institutional study that used data from Sapporo City General Hospital, Japan, on patients treated between January 2008 and May 2015. PARTICIPANTS: Five hundred Japanese GCC patients who started chemotherapy from January 2008 to May 2015. PRIMARY AND SECONDARY OUTCOME MEASURES: TE was diagnosed by reviewing all the reports of contrast-enhanced CT performed during the follow-up period. All types of thrombosis detected by CT or additional imaging tests, such as venous TE, arterial TE and cerebral infarction, were defined as TE. Medical records of all identified patients were reviewed and potential risk factors for TE, including clinicopathological backgrounds, were collected. We defined the following patients as 'active cancer'; patients with unresectable advanced GCC, cancer recurrence during or after completing adjuvant chemotherapy and/or presence of other malignant tumours. RESULTS: Of the 500 patients, 70 patients (14.0%) developed TE during the follow-up period. TEi was 9.2% and 17.3% in GCC patients, 18.1% and 3.5% in active and non-active cancer patients, and 24.0% and 12.9% in multiple and single primary, respectively. Multivariate logistic regression analysis showed that colorectal cancer (CRC) (OR 2.371; 95% CI 1.328 to 4.233), active cancer (OR 7.593; 95% CI 2.950 to 19.543) and multiple primary (OR 2.527; 95% CI 1.189 to 5.370) were independently associated with TEi. CONCLUSION: TEi was 14.0% among Japanese GCC patients received chemotherapy, and was significantly higher among patients with CRC, active cancer and multiple primary than among those with gastric cancer, non-active cancer and single primary, respectively. TRIAL REGISTRATION NUMBER: UMIN000018912.

A Prospective Observational Study on Effect of Short-Term Periodic Steroid Premedication on Bone Metabolism in Gastrointestinal Cancer (ESPRESSO-01).

BACKGROUND: A multicenter prospective observational study evaluated the effect of gastrointestinal cancer chemotherapy with short-term periodic steroid premedication on bone metabolism. PATIENTS AND METHODS: Seventy-four patients undergoing chemotherapy for gastrointestinal cancer were studied. The primary endpoints were changes in bone mineral densities (BMDs) and metabolic bone turnover 16 weeks after initiation of chemotherapy. BMDs, measured by dual-energy x-ray absorptiometry, and serum cross-linked N-telopeptides of type I collagen (sNTX), and bone alkaline phosphatase (sBAP) were assessed for evaluation of bone resorption and formation, respectively. RESULTS: In 74.3% (55/74) of the patients, BMDs were significantly reduced at 16 weeks relative to baseline. The percent changes of BMD were -1.89% (95% confidence interval [CI], -2.67% to -1.11%: p < .0001) in the lumbar spine, -2.24% (95% CI, -3.59% to -0.89%: p = .002) in the total hip, and -2.05% (95% CI, -3.11% to -0.99%: p < .0001) in the femoral neck. Although there was no significant difference in sNTX levels during 16 weeks (p = .136), there was a significant increase in sBAP levels (p = .010). Decreased BMD was significantly linked to number of chemotherapy cycles (p = .02). There were no significant correlations between changes in BMDs and the primary site of malignancy, chemotherapy regimens, total cumulative steroid dose, steroid dose intensity, and additive steroid usage. CONCLUSION: Gastrointestinal cancer chemotherapy with periodic glucocorticoid premedication was associated with reduced BMD and increased sBAP levels, which were linked to number of chemotherapy cycles but independent of primary site, chemotherapy regimen, duration, and additive steroid usage. The Oncologist 2017;22:592-600 IMPLICATIONS FOR PRACTICE: Bone health and the management of treatment-related bone loss are important for cancer care. The present study showed that a significant decrease in bone mineral density (BMD) and an increase in serum bone alkaline phosphatase levels occurred in gastrointestinal cancer patients receiving chemotherapy, which were linked to number of chemotherapy cycles but were independent of primary site, chemotherapy regimen, total steroid dose, and steroid dose intensity. Surprisingly, it seems that the decreasing BMD levels after only 16 weeks of chemotherapy for gastrointestinal cancer were comparable to that of 12-month adjuvant aromatase inhibitor therapy for early-stage breast cancer patients.

Discovery of a small peptide from combinatorial libraries that can activate the plant immune system by a jasmonic acid signaling pathway.

Plants defend themselves by using an innate immune system that is activated in response to a variety of molecules derived from pathogens. These molecules have provided profound insights into the mechanisms of pathogen recognition and subsequent signaling pathways in plants. In the present study, we screened a combinatorial random hexapeptide library for peptides that activate the plant immune system, by using a cell-based high-throughput screening system in which H(2)O(2) generation was monitored. We discovered a novel small peptide (YGIHTH-amide, PIP-1) that triggered H(2)O(2) production in tobacco and tomato cells, but not in Arabidopsis cells. PIP-1 induced significant levels of phytoalexin biosynthesis and defense-related gene expression in tobacco cells; this is likely to be activated by a jasmonic acid pathway.

Target biopsy using magnifying endoscopy in clinical management of gastric mucosa-associated lymphoid tissue lymphoma.

BACKGROUND AND AIM: We have reported the characteristics of magnified endoscopic images of gastric mucosa-associated lymphoid tissue (MALT) lymphoma before and after treatment. In this study, we investigated the diagnostic efficacy of magnified endoscopic images for target biopsy and evaluation of clinical remission. METHODS: Twenty-one patients diagnosed with localized gastric MALT lymphoma were enrolled. Magnified endoscopy was performed prior to treatment and at a mean period of 1.8 months (1-6 months) after therapy (Helicobacter pylori eradication in 19 patients and radiation therapy in two patients). Microstructural pattern and abnormal vessels in the lesions were assessed, and corpus mucosa without lymphoma was divided into H. pylori-negative mucosa and H. pylori-positive mucosa. Biopsy was the gold standard in this study. RESULTS: Nonstructural areas with abnormal vessels were observed in all patients before treatment. Fifteen patients achieved pathological complete remission. Disappearance of nonstructural areas and abnormal vessels after therapy was associated with pathological remission. Sensitivities of these findings for diagnosis were 76.9% and 85.7%, respectively, and the specificities were 87.5% and 85.7%, respectively. H. pylori eradication therapy was invalid in three patients with H. pylori-negative mucosa in magnified images. CONCLUSIONS: Magnifying endoscopy may be useful for target biopsy of superficial gastric MALT lymphoma in clinical management.

Characteristics of magnified endoscopic images of gastric extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue, including changes after treatment.

BACKGROUND: The utility of magnifying endoscopy for diagnosis of epithelial tumors has been reported, but there are few reports for nonepithelial tumors. OBJECTIVE: To determine the characteristics of magnified images of gastric extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) before and after treatment. DESIGN: This was a retrospective study. SETTING: Endoscopy Unit, Hokkaido University Hospital. PATIENTS: Eleven patients diagnosed with MALT lymphoma were enrolled. INTERVENTIONS: The microstructural pattern, collecting venules, and abnormal vessels in gastric MALT lymphoma were assessed before treatment and at 4 to 7 months after treatment by using magnifying endoscopy. MAIN OUTCOME MEASUREMENT AND RESULTS: The characteristics of magnified endoscopic images before treatment were the disappearance of gastric pits and the appearance of abnormal vessels. Ten cases of Helicobacter pylori-infected MALT lymphoma were treated by H. pylori eradication, and 1 H. pylori-negative case was treated by radiation therapy after eradication therapy. Ten patients achieved complete disease remission. After the treatment, recovery of gastric pits and subepithelial capillary network, and the disappearance of abnormal vessels were revealed by magnifying endoscopy. LIMITATION: This was a small pilot study. CONCLUSIONS: Magnified findings of gastric MALT lymphoma before and after therapy seem to correlate with complete response and no response.

Endoscopic diagnosis of early squamous neoplasia of the esophagus with iodine staining: high-grade intra-epithelial neoplasia turns pink within a few minutes.

BACKGROUND AND AIM: The ability to detect early squamous neoplasia of the esophagus can be enhanced considerably by iodine staining during endoscopic examination; however, there has been no study on distinguishing high-grade intra-epithelial squamous neoplasia from low-grade dysplasia by endoscopic examination. We assumed that high-grade intra-epithelial neoplasia could be identified as iodine-unstained areas more distinct and reddish than low-grade dysplasia after the brown color of iodine solution has faded, because there is almost no remaining glycogen-containing epithelium in high-grade intra-epithelial neoplasia. METHODS: Seventy-nine patients who were found to have demarcated iodine-unstained areas (0.5 cm to 1.5 cm at widest part, 121 lesions in total) were studied. After a target lesion was found, the lesion was observed for about 3 min and its discoloration was evaluated. If a light-pink part appeared in the iodine-unstained area, the lesion was regarded as being positive for pink color. If no light-pink part was observed in the lesion within 3 min, the lesion was regarded as being negative for pink color. RESULTS: Thirty-four (87.2%) of the 39 lesions diagnosed as pink-color positive were histologically confirmed to be high-grade intra-epithelial squamous neoplasia or squamous cell carcinoma, whereas only three (3.7%) of the 82 lesions diagnosed as negative for pink color were histologically confirmed to be high-grade intra-epithelial squamous neoplasia (P < 0.0001). Using the pink-color sign as a diagnostic index for high-grade intra-epithelial squamous neoplasia and squamous cell carcinoma, sensitivity was 91.9% and specificity was 94.0%. CONCLUSION: By using the pink-color sign for endoscopic diagnosis, accurate diagnosis without endoscopic biopsy for iodine-unstained areas was possible.

New method for long-term monitoring of intragastric pH.

AIM: Consecutive monitoring of intragastric pH using the Bravo capsule. METHODS: We put threads through a Bravo capsule and then affixed it to the gastric wall by endoscopic hemoclipping in seven subjects. Study data were uploaded to a computer via Datalink every 48 h. In this way, repeated monitoring of intragastric pH was undertaken. RESULTS: All subjects were able to monitor gastric pH over a 1-wk period, and five for > 2 wk. No complications were encountered during the monitoring. After pH monitoring, we safely retrieved the capsule endoscopically. CONCLUSION: Clipping a Bravo capsule onto the gastric wall enabled long-term intragastric pH monitoring. This is a methodological report of pH monitoring over a period of > 2 wk.

[Diagnostic imaging of NSAID ulcers].

Nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin cause frequently gastrointestinal injuries. In the acute phase of NSAIDs damage, endoscopic findings of gastroduodenal injuries are observed as acute gastroduodenal mucosal lesion (AGDML). Especially, non-aspirin NSAIDs cause sometimes hemorrhagic gastroduodenal ulcers. In the chronic phase of NSAIDs damage, multiple antral erosions and/or ulcers with oozing, and punched-out antral ulcers are characteristic findings. Recently, it was noted by capsule-endoscopy and double-balloon endoscopy that NSAIDs induce more frequent small intestine lesions. The characteristic findings of them are multiple erosions and/or ulcers in various forms. Circular ulcers of the small intestine and colon ulcers, colitis are induced by NSAIDs lower frequency comparing with upper GI tract injuries. In conclusion, characteristic images of gastrointestinal injuries induced by NSAIDs are multiple erosions and ulcers with bleeding without symptoms. It is most important asking about use of NSAIDs if we see such endoscopic images.

Endoscopic submucosal dissection for treatment of early stage hypopharyngeal carcinoma.

BACKGROUND: Early detection of hypopharyngeal carcinoma is increasingly possible and patients with such early lesions can be treated with endoscopic resection. OBJECTIVE: To identify the optimal relationship between the mucosal defect of the hypopharynx and malfunction of the hypopharynx after endoscopic resection of early hypopharyngeal carcinoma. DESIGN: Case series. SETTING: Referral center in Japan. PATIENTS: Four patients with early-stage squamous cell carcinoma of the hypopharynx underwent endoscopic submucosal dissection (ESD). By using ESD, an accurate incision line close to the tumor margin could be confirmed while performing treatment. ESD was performed with a small-caliber-tip transparent hood (ST-hood) to open the incision line for better visualization of the submucosa. MAIN OUTCOME MEASUREMENTS: Feasibility of en bloc resection, complications, and recurrence after ESD. RESULTS: No early or late complications due to treatment occurred in the patients. Histological examination of resected specimens revealed that 2 patients had carcinoma in situ and 2 patients had tumor invasion of the subepithelium. There was no local recurrence or distant metastasis in any of the patients during the follow-up period (3-14 months). CONCLUSIONS: We consider that ESD is the optimal method for endoscopic resection not only because it enables an en bloc resected specimen to be obtained but also because it can prevent removal of excess mucosa of the hypopharynx, which is a very narrow and important organ related to swallowing and speech.

Histologic results of EMR for esophageal lesions diagnosed as high-grade intraepithelial squamous neoplasia by endoscopic biopsy.

BACKGROUND: Biopsy specimens obtained from esophageal lesions detected in endoscopic screening with iodine staining have often been diagnosed as high-grade intraepithelial squamous neoplasia (WHO 2000). However, a management strategy for such lesions has not been established. The purpose of this study was to perform EMR for such lesions and to determine the actual tumor stage in patients with complete resection and the outcomes after EMR. PATIENTS: During the study period, 51 patients were found to have esophageal lesions diagnosed as high-grade intraepithelial squamous neoplasia by using endoscopic iodine staining in biopsy specimens. All of the patients underwent EMR, and resected specimens were reviewed microscopically. RESULTS: Histologic examination of totally resected specimens revealed that 12 (23.5%) of the 51 patients had tumor invasion of the lamina propria mucosae and that 4 (7.8%) had tumor invasion of the muscularis mucosae. The remaining 35 patients (68.6%) were confirmed to have high-grade intraepithelial squamous neoplasia. The invasive focus in all of the 16 lesions of invasive squamous-cell carcinoma was surrounded by high-grade intraepithelial squamous neoplasia. After a median of 23 months of follow-up, there were two recurrences, and those patients required second EMR. CONCLUSIONS: Histologic results suggested that high-grade intraepithelial squamous neoplasia of the esophagus has characteristics of carcinoma in the preinvasive stage. EMR should be performed for esophageal lesions diagnosed by endoscopic biopsy as high-grade intraepithelial squamous neoplasia, not only because of its probable malignant potential but also because more than 30% of such lesions are actually invasive carcinoma.