Search Results (226)

After the first release of synthalin B (dodecamethylenbiguanide) in 1928 and its later retraction in the 1940s in Germany, the retraction of phenformin (N-Phenethylbiguanide) and of Buformin in the USA (but not outside) because of the lethal complication of acidosis seemed to have put an end to the era of the biguanides as oral antidiabetics. The strongly hygroscopic metformin (1-1-dimethylbiguanide), first synthesized 1922 and resuscitated as an oral antidiabetic (type 2 of the elderly) compound first released in 1959 in France and in other European countries, was used in the first large multicenter prospective long-term trial in England in the UKPDS (1977–1997). It was then released in the USA after a short-term prospective trial in healthy overweight “young” type 2 diabetics (mean age 53 years) in 1995 for oral treatment of type 2 diabetes. It was, however, prescribed to mostly multimorbid older patients (above 60–65 years of age). Metformin is now the most used oral drug for type 2 diabetes worldwide. While intravenous administration of biguanides does not have any glucose-lowering effect, their oral administration leads to enormous increase in their intestinal concentration (up to 300-fold compared to that measured in the blood), to reduced absorption of glucose from the diet, to increased excretion of glucose through the stool, and to decrease in insulin serum level through increased hepatic uptake and decreased production. Intravenously injected F18-labeled glucose in metformin-treated type 2 diabetics accumulates in the small and even more in the large intestine. The densitometry picture observed in metformin-treated overweight diabetics is like that observed in patients after bowel-cleansing or chronically taking different types of laxatives, where the accumulated radioactivity can even reach values observed in colon cancer. The glucose-lowering mechanism of action of metformin is therefore not only due to inhibition of glucose uptake in the small intestine but also to “attraction” of glucose from the hepatocyte into the intestine, possibly through the insulin-mediated uptake in the hepatocyte and its secretion into the bile. Furthermore, these compounds have also a diuretic effect (loss of sodium and water in the urine) Acute gastrointestinal side effects accompanied by fluid loss often lead to the drugs’ dose reduction and strongly limit adherence to therapy. Main long-term consequences are “chronic” dehydration, deficiency of vitamin B12 and of iron, and, as observed for all the biguanides, to “chronic” increase in fasting and postprandial lactate plasma level as a laboratory marker of a clinical condition characterized by hypotension, oliguria, adynamia, and evident lactic acidosis. Metformin is not different from the other biguanides: synthalin B, buformin, and phenformin. The mechanism of action of the biguanides as antihyperglycemic substances and their side effects are comparable if not even stronger (abdominal pain, nausea, vomiting, diarrhea, fluid loss) to those of laxatives. Full article

Chronic atrophic gastritis and intestinal metaplasia (IM) are gastric precancerous conditions (GPCs) associated with an increased risk of gastric cancer. Early detection and accurate characterization of GPC are therefore crucial for risk stratification and the implementation of preventive strategies. In the absence of clear mucosal changes observed through white-light imaging (WLI) or virtual chromoendoscopy, endocytoscopy can help unveil the presence of GPC by enabling in vivo assessment of nuclear and cellular structures at ultra-high magnification. Endocytoscopy is typically performed using WLI following dye-based staining of the mucosa. In this case, we demonstrate that combining endocytoscopy with the texture and color enhancement imaging (TXI) mode substantially improves the assessment of the gastric mucosa. In a 61-year-old man undergoing esophagogastroduodenoscopy, WLI showed multifocal erythema in the stomach, without clearly visible lesions on either WLI or narrow-band imaging. Conventional endocytoscopy revealed multiple small spots of IM with characteristic changes in glandular structures, which were even more evident when using the TXI mode. Histological analysis of targeted biopsies confirmed small foci of IM in both the antrum and corpus. The patient was enrolled in a surveillance program because of his clinical background. The combination of endocytoscopy with the TXI mode significantly enhances the delineation of mucosal and cellular architecture, supporting a more accurate optical diagnosis. Full article

Transmembrane protein 43 (TMEM43 or LUMA) encodes a highly conserved protein found in the nuclear and endoplasmic reticulum membranes of many cell types and the intercalated discs and adherens junctions of cardiac myocytes. TMEM43 is involved in facilitating intra/extracellular signal transduction to the nucleus via the linker of the nucleoskeleton and cytoskeleton complex. Genetic mutations may result in reduced TMEM43 expression and altered TMEM43 protein cellular localization, resulting in impaired cell polarization, intracellular force transmission, and cell–cell connections. The p.S358L mutation causes arrhythmogenic right ventricular cardiomyopathy type-5 and is associated with increased absorption of lipids, fatty acids, and cholesterol in the mouse small intestine, which may promote fibro-fatty replacement of cardiac myocytes. Mutations (p.E85K and p.I91V) have been identified in patients with Emery–Dreifuss Muscular Dystrophy-related myopathies. Other mutations also lead to auditory neuropathy spectrum disorder-associated hearing loss and have a negative association with cancer progression and tumor cell survival. This review explores the pathogenesis of TMEM43 mutation-associated diseases in humans, highlighting animal and in vitro studies that describe the molecular details of disease processes and clinical, histologic, and molecular manifestations. Additionally, we discuss TMEM43 expression-related conditions and how each disease may progress to severe and life-threatening states. Full article

Background/Objectives: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Even though the screening programs have decreased the incidence rates, the prognosis for CRC varies depending on the stage at diagnosis. Thus, early diagnosis is still a big challenge due to screening methods, and subsequent diagnosis is not very sensitive. Methods: In this work, LC-MS-based metabolomics, a powerful and sensitive tool to study complex dynamic changes, was used to analyze 211 human fecal samples from control individuals (CTRL), adenoma (AA), and CRC patients. Results: Multivariate and univariate statistical analysis highlighted cholesteryl esters (CEs) and fecal haemoglobin, quantified by fecal immunochemical test (FIT), as relevant biomarkers that clearly differentiate CRC from AA and CTRL. Predictive models based on random forest and the area under the curve (AUC) of the receiver operating characteristic curve (ROC) demonstrate that CEs, together with FIT measurement, improved the CRC and CTRL classification, but not AA. This study revealed that the AA group is a transitional stage with high heterogeneity. The increased tendency observed in CEs from CTRL to CRC might be related to the imbalance of cholesterol homeostasis due to cancer cells requiring a high cholesterol level for cell development and proliferation. The free cholesterol is probably obtained from CEs, as it is the most cost/effective way to obtain the needed cholesterol. Conclusions: The accumulation of CEs is produced by two possible approaches: (1) dysfunction of cholesterol absorption in the small intestine and/or (2) transported inside exosomes from cell to cell to promote proliferation. Full article

Background/Objective: Immune checkpoint inhibitors (ICIs) are highly effective cancer therapies used across a broad spectrum of malignancies. They function by disrupting immune inhibitory pathways, resulting in an amplified immune response against tumors. However, this heightened immune activity can predispose patients to immune-mediated colitis (IMC), which is graded using the Common Terminology Criteria for Adverse Events (CTCAE) and can range from mild diarrhea to severe colitis. Prior studies have shown that fecal stream diversion can modify the gut microbiome and influence the severity of intestinal inflammation. This study investigates the impact of fecal stream diversion on IMC outcomes in cancer patients receiving ICIs. Methods: We conducted a retrospective cohort study of patients treated with ICIs from 2016 to 2023 who had a history of fecal stream diversion. Demographic, oncologic, and toxicity-related data were collected. Patients with active gastrointestinal infections, autoimmune GI diseases, or graft-versus-host disease were excluded. Descriptive statistics and univariate and multivariate logistic regression analyses were performed using SAS version 9.4. Results: A total of 44 patients were included and categorized into two groups based on the timing of bowel stoma creation relative to the IMC event. CTCAE grade for diarrhea was used to assess GI toxicity. While overall CTCAE grade distribution for diarrhea did not differ significantly between groups (p = 0.22), Hispanic ethnicity was significantly associated with a lower CTCAE grade compared to non-Hispanic or Latino individuals (OR [95% CI] = 0.12 [0.02, 0.62], p = 0.011). In contrast, higher CTCAE grades were significantly associated with ileostomy versus colostomy (OR [95% CI] = 3.21 [1.01, 10.18], p = 0.048) and in patients without an ostomy at the time of diarrhea onset compared to those with an ostomy (OR [95% CI] = 8.87 [2.51, 31.31], p = 0.0007). Conclusions: Our findings suggest that the CTCAE diarrhea grade is significantly associated with ethnicity, type of stoma, and presence of ostomy at the time of diarrhea. Limitations include the retrospective study design and small sample size. These results contribute to understanding potential strategies for mitigating the serious gastrointestinal toxicities of ICIs. Full article

Drug resistance is still one of the main challenges for the treatment of colorectal cancer (CRC). Whilst some resistance mechanisms are well known, from the static therapy success rate, clearly, still much is undiscovered. Intracellular transport mechanisms have attracted attention as having a possible role in drug resistance, and here, the Endosomal Sorting Complex Required for Transport (ESCRT) protein family is studied as a source of drug resistance modulation using human CRC cell lines and clinical material. From an initial screening of ESCRT proteins in a panel of 10 CRC wild-type cell lines using immunoblotting, Vacuolar Protein Sorting-Associated Protein A4 (VPS4A) was identified as being consistently highly expressed, and it was selected for further investigation. Immunohistopathological evaluation in a small panel of CRC patient samples demonstrated high expression in the tumor epithelium compared to normal intestinal epithelium. The knockdown of VPS4A resulted in enhanced sensitivity of cells to oxaliplatin, and it was subsequently seen that oxaliplatin-resistant sublines had significantly higher VPS4A expression than their wild-type variants. In addition, it was demonstrated that a small molecule inhibitor of VPS4A, aloperine, could interact synergistically with oxaliplatin to enhance its sensitivity in an oxaliplatin-resistant cell line. We hypothesize from initial RNA sequencing analysis that the mechanism of action of VPS4A modulation is through depleting levels of the drug efflux transporter MRP2 in the cell, preventing oxaliplatin egress and increasing cell exposure to the drug. The evidence presented here thus indicates that ESCRT machinery, specifically VPS4A, may act as a modulator of oxaliplatin resistance in CRC. Full article

Capsule endoscopy (CE) has revolutionized gastrointestinal (GI) diagnostics by providing a non-invasive, patient-centered approach to observing the digestive tract. Conceived in 2000 by Gavriel Iddan, CE employs a diminutive, ingestible capsule containing a high-resolution camera, LED lighting, and a power supply. It specializes in visualizing the small intestine, a region frequently unreachable by conventional endoscopy. CE helps detect and monitor disorders, such as unexplained gastrointestinal bleeding, Crohn’s disease, and cancer, while presenting a lower procedural risk than conventional endoscopy. Contrary to conventional techniques that necessitate anesthesia, CE reduces patient discomfort and complications. Nonetheless, its constraints, specifically the incapacity to conduct biopsies or therapeutic procedures, have spurred technical advancements. Five primary types of capsule endoscopes have emerged: steerable, magnetic, robotic, tethered, and hybrid. Their performance varies substantially. For example, the image sizes vary from 256 × 256 to 640 × 480 pixels, the fields of view (FOV) range from 140° to 360°, the battery life is between 8 and 15 h, and the frame rates fluctuate from 2 to 35 frames per second, contingent upon motion-adaptive capture. This study addresses a significant gap by methodically evaluating CE platforms, outlining their clinical preparedness, and examining the underexploited potential of artificial intelligence in improving diagnostic precision. Through the examination of technical requirements and clinical integration, we highlight the progress made in overcoming existing CE constraints and outline prospective developments for next-generation GI diagnostics. Full article

Background/Objectives: Neurotensin receptors (NTSRs), members of the G protein-coupled receptor (GPCR) family, have been found to be overexpressed in several types of human cancers, including breast, colon, lung, liver, prostate, and pancreatic cancer. In particular, NTSR1 is overexpressed in at least 75% of pancreatic ductal adenocarcinomas. The aim of the present study was the development and evaluation of new ^99mTc-labeled nonpeptide NTSR1-antagonists for SPECT imaging of NTSR-positive tumors. Methods: Multistep syntheses of NTSR1 antagonist derivatives were performed following our previously described procedure. Two different chelating strategies were applied for ^99mTc radiolabeling to provide the [^99mTc]Tc-HYNIC complex [^99mTc]1 and the [^99mTc]Tc-tricarbonyl complex [^99mTc]2. Receptor binding assays were performed using hNTSR1-expressing CHO cells. Radiochemical yields (RCYs) were determined by radio-HPLC. For [^99mTc]1 and [^99mTc]2, log D_7.4, plasma protein binding, stability in human plasma and serum, and cellular uptake in HT-29 cells were determined. Biodistribution studies and small animal SPECT studies were performed in HT-29 tumor-bearing nude mice. Results: The radiosynthesis of [^99mTc]1 (log D_7.4 = −0.27) and [^99mTc]2 (log D_7.4 = 1.00) was successfully performed with RCYs of 94–96% (decay-corrected). Both radioligands were stable in human serum and plasma, showed plasma protein binding of 72% ([^99mTc]1) and 82% ([^99mTc]2), and exhibited high and specific uptake in HT-29 cells. Biodistribution studies in HT-29 tumor-bearing mice showed a higher tumor accumulation of [^99mTc]1 compared to [^99mTc]2 (8.8 ± 3.4 %ID/g vs. 2.7 ± 0.2 %ID/g at 2 h p.i.). [^99mTc]2 showed exceptionally high intestinal accumulation (49 ± 22 %ID/g at 1 h p.i.) and was therefore considered unfavorable. In the SPECT/CT imaging of HT-29 tumor xenografts, [^99mTc]1 showed a higher NTSR1-specific tumor uptake than [^99mTc]2 at all time points after tracer injection, with 12 ± 2.8 %ID/g for [^99mTc]1 vs. 3.1 ± 1.1 %ID/g for [^99mTc]2 at 4 h p.i. and adequate tumor-to-background ratios. Conclusions: In particular, the [^99mTc]Tc-HYNIC ligand ([^99mTc]1) showed promising preclinical results, being a potential candidate for SPECT imaging and, therefore, appropriate for translation into the clinic. Full article

Background: This study aimed to analyze the morbidity, mortality, and survival outcomes in patients with peritoneal surface malignancies who were initially considered candidates for cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) but were found to have unresectable disease, resulting in nontherapeutic exploratory laparotomy. Patients and Methods: We evaluated data from our referral center for the treatment of peritoneal surface malignancies between January 2008 and December 2022. Adverse events following nontherapeutic laparotomy were classified using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. Results: Among a cohort of 486 patients with peritoneal surface malignancies initially considered candidates for CRS + HIPEC, 46 cases (9.4%) were aborted due to the disease being deemed unresectable during exploratory laparotomy. The primary reasons for unresectability included extensive disease spread, observed in 28 patients, with massive small intestine involvement detected in 13 of these cases. The median duration of surgery was 90 min (range: 60–180 min). Postoperative complications occurred in 10 patients (22%), with a mortality rate of 4.3% (2 patients). Survival was significantly lower in patients who did not receive adjuvant systemic chemotherapy with palliative intent (4 months vs. 15 months, p < 0.01). Conclusions: Exploratory laparotomy in patients with peritoneal surface malignancies considered for CRS with HIPEC carries a substantial risk of complications. Improved preoperative staging using advanced technologies such as radiomics and laparoscopy is expected to reduce the number of patients undergoing nontherapeutic laparotomy. Full article

Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic condition marked by persistent intestinal inflammation of unknown etiology. Disease onset involves genetic predisposition and environmental factors that disrupt the intestinal immune homeostasis. The intestinal microbiome and immune response play pivotal roles in disease progression. Advances in molecular therapies and early interventions have reduced surgery rates; however, colorectal cancer (CRC) remains a significant concern, driven by chronic inflammation. In UC, the risk of UC-associated neoplasia (UCAN) increases with disease duration, while CD patients face elevated risks of small intestine, anal fistula, and anal canal cancers. Endoscopic surveillance is advised for UCAN, but optimal screening intervals remain undefined, and no established guidelines exist for CD-associated cancers. UCAN morphology often complicates detection due to its flat, inflammation-blended appearance, which differs pathologically from sporadic CRC (sCRC). UCAN is frequently surrounded by dysplasia, with p53 mutations evident at the dysplasia stage. IBD-associated gastrointestinal cancers exemplify inflammation-driven carcinogenesis with distinct molecular mechanisms from the adenoma-carcinoma sequence. This review explores the epidemiology, risk factors, clinical and pathological features, current surveillance practices, and molecular pathways underlying inflammation-associated cancers in IBD. Full article

Sanghuang (Sanghuangporus sanghuang, SS) is a medicinal fungus with multiple pharmacological effects, including antioxidant, anti-inflammatory, immune-boosting, and anti-cancer activities. 5-fluorouracil (5-FU) is a commonly used chemotherapeutic agent for the treatment of colorectal cancer. It primarily exerts its antitumor effect by inhibiting DNA and RNA synthesis, leading to cell apoptosis. However, it frequently induces adverse effects These issues limit the clinical application of 5-FU. This research aims to determine the potential of SS as a therapeutic agent in reducing 5-FU-induced intestinal mucositis in a mouse model. The results indicated that 5-FU administration significantly increased diarrhea severity, reduced colon length, caused small intestinal villus atrophy, disrupted intestinal architecture, led to insufficient crypt cell proliferation, and resulted in weight loss. It also significantly upregulated inflammatory responses, apoptosis, oxidative stress, and epithelial–mesenchymal transition (EMT) pathways, and disrupted the integrity of intestinal mucosal tight junction, while elevating pro-inflammatory cytokines and reducing antioxidant capacity. However, SS significantly ameliorating alleviating the adverse impacts of the chemotherapeutic agent on the intestinal mucosa. In conclusion, this investigation provides the first evidence of the protective effects of SS on 5-FU-induced mucositis. These findings suggest SS as a potential therapeutic application, offering a promising strategy for reducing the adverse effects of 5-FU chemotherapy and improving the treatment and quality of life for colorectal cancer patients. Full article

Background/Objectives: Neuroendocrine tumors (NETs) can arise in any organ and are most commonly found in the lungs and gastroenteropancreatic (GEP) system. GEP-NETs represent a small percentage of gastrointestinal cancers, and therefore, the standard treatment is not well-defined, especially for advanced disease. Our objective is to review GI NETs among veterans and analyze their therapeutic outcomes. Methods: A total of 61 GI NET cases were identified from our institution from 2019–2024. In total, twenty-seven review papers, ten population-based/multicenter/outcome studies, six case reports, and one case series were reviewed for the literature review. Results: The incidence of GI NETs at our institution was higher than the known epidemiology of GI NETs. Small intestine NETs were one of the most common sites of GEP-NETs at our institution, with only one of nineteen cases being grade 3 poorly differentiated neuroendocrine carcinoma. All cases of colonic and rectal NETs had good clinical outcomes consistent with findings from the literature. Most of the gastric NETs were type 1 and had benign courses of disease, except for one case with an intermediate grade and metastatic liver lesions. One case of esophageal neuroendocrine carcinoma (E-NEC) showed a complete response to chemotherapy despite a significant tumor burden on presentation and high-grade pathology, while another case of ENEC had recurrent disease despite systemic therapy. Conclusions: While the role of surgery or endoscopic resection is limited to localized tumors, combined treatment with chemoradiation can significantly improve patient outcomes, especially in high-grade, poorly differentiated tumors. Further studies are needed to establish systemic (i.e., chemotherapy and radiation) treatment strategies for poorly differentiated GI NETs. Full article

The gastrointestinal (GI) tract, an integral part of the digestive system, absorbs nutrients from ingested food, starting from the mouth to the anus. GI tract cancer significantly impacts global health, necessitating precise treatment methods. Radiation oncologists use X-ray beams to target tumors while avoiding the stomach and intestines, making the accurate segmentation of these organs crucial. This research explores various combinations of encoders and decoders to segment the small bowel, large bowel, and stomach in MRI images, using the UW-Madison GI tract dataset consisting of 38,496 scans. Encoders tested include ResNet50, EfficientNetB1, MobileNetV2, ResNext50, and Timm_Gernet_S, paired with decoders UNet, FPN, PSPNet, PAN, and DeepLab V3+. The study identifies ResNet50 with DeepLab V3+ as the most effective combination, assessed using the Dice coefficient, Jaccard index, and model loss. The proposed model, a combination of DeepLab V3+ and ResNet 50, obtained a Dice value of 0.9082, an IoU value of 0.8796, and a model loss of 0.117. The findings demonstrate the method’s potential to improve radiation therapy for GI cancer, aiding radiation oncologists in accurately targeting tumors while avoiding healthy organs. The results of this study will assist healthcare professionals involved in biomedical image analysis. Full article

Objective: Liver cirrhosis (LC) progression induces intestinal microbiota abnormalities, such as small intestinal bacterial overgrowth (SIBO), and these changes lead to the inflow of gut pathogens and their degradation products into the vessels, causing cirrhotic complications such as hepatic encephalopathy (HE). Methods: To clarify the relationship between the development of overt HE and SIBO, we conducted a three-year observation after assessment of SIBO in patients with LC. Results: In the analysis of 107 patients, with a mean follow-up duration of 29.4 months, 31 were diagnosed with SIBO and 30 with covert HE. In the Cox multivariate regression analysis for prognosis, the Child–Pugh score, blood urea nitrogen level, and the Union for International Cancer Control (UICC) stage of hepatocellular carcinoma were derived using the following five factors: white blood cell count, blood urea nitrogen level, Child–Pugh score, UICC stage, and serum aspartate aminotransferase and alkaline phosphatase levels (p = 0.002, hazard ratio [HR] 3.733, 95% confidence interval [CI] 1.592–8.754, p = 0.001, HR 1.076, 95% CI 1.030–1.123, and p < 0.001, HR 2.767, 95% CI 1.780–4.302, respectively). Furthermore, in the Cox multivariate regression analysis for overt HE development, covert HE and methane-producing SIBO were derived using the following four factors: methane-producing SIBO, UICC stage, covert HE, and serum ammonia levels (p = 0.038, HR 5.008, 95% CI 1.096–22.892 and p = 0.006, HR 8.597, 95% CI 1.881–39.291, respectively). Conclusions: M-SIBO positivity was a significant predictor of overt HE. Full article

Background: It has been documented that radiation can influence the pharmacokinetics of chemotherapy drugs, yet the underlying mechanisms remain poorly understood. In clinical practice, a considerable number of cancer patients undergo radiotherapy, and those with comorbid hypertension required antihypertensive drugs, including valsartan, an angiotensin II receptor blocker. However, there is no research investigating whether radiotherapy poses a risk of altering the pharmacokinetics. Objective: The objective of this study is to investigate the impact of X-ray abdominal irradiation on the pharmacokinetics of valsartan and to preliminarily elucidate the underlying mechanism. Methods: The pharmacokinetics of valsartan after X-ray irradiation was investigated in rats and in vitro by detecting the concentration of valsartan in biological samples by LC-MS/MS. The oxidative stress in the intestine and the mRNA expression of partial transporters and Nrf2 in the liver and small intestine were detected by biochemical reagent kit or RT-qPCR. Results: In vivo studies showed that X-ray irradiation resulted in a significant decrease in the AUC and C_max of valsartan, and the cumulative fractional excretion of valsartan in bile and urine, although there was no significant change in fecal excretion. In vitro studies showed that the uptake of valsartan by both intestine and Caco-2 cells decreased after irradiation, and the cellular uptake could be restored by Mrp2 inhibitor MK571. The levels of GSH, SOD, and CAT in the intestine decreased after irradiation. The mRNA expressions of Mrp2 and P-gp in the intestine or Caco-2 cells were significantly upregulated after irradiation while there was a downregulation of Mrp2 and oatp1b2 in liver. Nrf2 and HO-1 in the intestine were also significantly upregulated, which clarified the involvement of Mrp2 and the possible molecular mechanism. Conclusions: Abdominal X-ray irradiation can cause oxidative stress and upregulate intestinal Mrp2, which may be related to oxidative stress and upregulation of Nrf2, reducing intestinal absorption of valsartan and leading to a significant decrease in the blood concentration of valsartan. Full article