Death receptors 4/5 mediate tumour sensitivity to natural killer cell-mediated cytotoxicity in mismatch repair deficient colorectal cancer

BACKGROUND

Identifying the target of natural killer (NK) cells in colorectal cancer (CRC) is critical for optimising the clinical use of NK cell-mediated immunotherapy. Mismatch repair deficiency (dMMR) is associated with high immune cell infiltration and MHC Class I defects. Whether dMMR CRC responses to NK cell therapy remains unclear.

METHODS

MLH1, DR4, and DR5 knockout cell lines were established using CRISPR-Cas9 system. NK92-MI or NK cell isolated from BABL/C mice were used as effector cells against tumour cells. Inflammatory cytokines secretion by CRC cells was assessed via cytokine analysis. NK-cell-deficient/proficient animal models were used to validate the NK cell sensitivity.

RESULTS

We observed that dMMR CRC cells were more sensitive to NK cell-mediated cytotoxicity than were mismatch-repair-proficient (pMMR) CRC cells. In dMMR CRC, Death receptor (DR)4/5 was upregulated and mediated sensitivity to NK cell-mediated cytotoxicity. DR4/5-mediated secretion of interleukin -12 sustained NK cell viability in dMMR CRC. NK cell depletion induced dMMR CRC tumour growth, and NK cell transfer inhibited lung metastasis of dMMR CRC with DR4/5 expression in vivo. TP53 upregulated DR4/DR5 expression in dMMR CRC.

CONCLUSIONS

dMMR associated with increased sensitivity to NK cell-mediated cytotoxicity in CRC. DR4/DR5 sensitise dMMR CRC to NK cell-mediated cytotoxicity.

[Overexpression of tuftelin and KLF-5 and its clinicopathological features in hepatitis B virus-related hepatocellular carcinoma]

Objective: To analyze and evaluate the expressions and clinical value of tuftelin (TUFT1) and Krüppel-like factor 5 (KLF5) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) tissues. Method: KLF5 mRNA and TUFT1 mRNA transcriptional status in cancer and non-cancer groups were compared according to the Cancer Genome Atlas (TCGA) database. The differences and prognostic value between the groups were analyzed. Postoperative liver cancer and its paired pericancerous tissues, with the approval of the ethics committee, were collected to build tissue chips. The expression of KLF5 and TUFT1 and their intracellular localization were verified by immunohistochemistry. Tissue expression and clinicopathological characteristics were analyzed by immunoblotting. SPSS software was used to analyze the relationship between SPSS and patient prognosis. Results: The transcription level of TUFT1 or KLF5 mRNA was significantly higher in the HCC group than the non-cancer group (P < 0.001), according to TCGA data. Immunohistochemistry and Western blotting examination confirmed the overexpression of TUFT1 and KLF5 in human HCC tissues, which were mainly localized in the cytoplasm and cell membrane. The positivity rates of TUFT1 and KLF5 were 87.1% ( χ(2) = 18.563, P < 0.001) and 95.2% ( χ(2) = 96.435, P < 0.001) in HCC tissues, and both were significantly higher than those in the adjacent group. The expression intensity was higher in stage III-IV than stage I-II of the International Union Against Cancer standard (P < 0.01). The clinicopathological features showed that the abnormalities of the two were significantly related to HBV infection, tumor size, extrahepatic metastasis, TNM stage, and ascites. Univariate analysis was related to tumor size, HBV infection, and survival. Multivariate analysis was an independent prognostic factor for patients with HCC. Conclusion: TUFT1 and KLF5 may both be novel markers possessing clinical value in the diagnosis and prognosis of HBV-related HCC.

Sodium fluoride-induced autophagy of ameloblast-like cells via the p-ULk1/ATG13/LC3B pathway in vitro

OBJECTIVE

To investigate the effects of sodium fluoride on the ameloblast and reveal the mechanism of dental fluorosis.

MATERIALS AND METHODS

Mouse ameloblast-like cell line (ALC) cells were treated with various concentrations of NaF, and subjected to Incucyte, fluorescence immunoassay, transmission electron microscopy, reverse transcription quantitative polymerase chain reaction (RT-qPCR), western blot for autophagy examination, alkaline phosphatase and alizarin red staining for mineralization after osteogenic induction.

RESULTS

NaF exerts a dose-dependent inhibitory effect on ALC cell growth. TEM and fluorescence immunoassay showed that 1.5 mM or higher concentrations of NaF could induce a fusion of lysosome and mitochondria, finally increasing the number of autophagosome. RT-qPCR and western blot showed that the upregulation of autophagy related gene 13 (ATG13), downregulation of phosphorylated Unc-51-like kinase 1 (p-ULK1) were found in NaF-induced autophagy of ALC cells. The knockdown of ATG13 could rescue it as well as the expression of p-ULK1 and LC3B. Besides, alizarin red staining showed that fluoride under these concentrations could promote the mineralization of ALC.

CONCLUSIONS

The data show that fluoride in higher concentration can induce autophagy via the p-ULk1/ATG13/LC3B pathway of ALCs than lower ones promote mineralization in vitro, which provides insight into the function of NaF in the autophagy and mineralization of ameloblast.

[A preliminary study on the establishment of a subcutaneous allergen-specific immunotherapy center]

Allergic diseases can notably affect a patient's quality of life. World Health Organization (WHO) has identified these diseases as one of the key areas for research and prevention in the 21st century. Currently, allergen-specific immunotherapy is viewed as a potential treatment approach that could modify the natural progression of allergic diseases, thus being recognized as a crucial tactic in their prevention and treatment. Nonetheless, the broad implementation of allergen-specific immunotherapy in clinical settings continues to confront challenges. One significant issue is the absence of standardized centers for subcutaneous allergen-specific immunotherapy. This article presents several perspectives and recommendations for establishing a standardized subcutaneous allergen-specific immunotherapy center.

Dose-related effects of early-life intake of sn-2 palmitate, a specific positionally distributed human milk fatty acid, on the composition and metabolism of the intestinal microbiota

sn2 Palmitate in human milk plays an important role in the physiological health of infants by reducing mineral loss, improving stool hardness, and relieving constipation. Also, sn-2 palmitate modulates intestinal microbiota. However, it remains unclear whether the effects of sn-2 palmitate on infant gut microbiota are dose-dependent. In this study, we investigated the effects of low, medium, and high doses (600, 1,800, and 5,400 mg/kg body weight, respectively) of sn-2 palmitate on the structure, composition, and metabolic function of intestinal microbes in mice. Our results showed that high doses of sn-2 palmitate significantly modulated α- and β-diversity of the intestinal microbiota. The relative abundance of Lachnospiraceae_NK4A136_group decreased with increasing doses of sn-2 palmitate. In contrast, the abundances of Bacteroidetes phylum, Bacteroides, uncultured_Lachnospiraceae, and uncultured_Muribaculaceae were positively correlated with sn-2 palmitate doses. The number of genes predicted encoding autophagy-yeast, phospholipase D signaling pathway, and pentose and glucuronate interconversion metabolic functions of intestinal microbiota increased with increasing doses of sn-2 palmitate. In addition, low and medium doses of sn-2 palmitate significantly upregulated the arginine and proline metabolic pathways, and high doses of sn-2 palmitate significantly increased purine metabolism. Our results revealed that the effects of sn-2 palmitate intake early in life on the composition and metabolism of the intestinal microbiota of mice showed dose-related differences. The study is expected to provide a scientific basis for the development of infant formulas.

[Chinese expert guidance on overall application of lenvatinib in hepatocellular carcinoma]

Lenvatinib mesylate is an oral receptor tyrosine kinase inhibitor against targets of vascular endothelial growth factor receptors 1-3, fibroblast growth factor receptors 1-4, platelet-derived growth factor receptor α, stem cell growth factor receptor, and rearranged during transfection, et al. Lenvatinib has been approved by the National Medical Products Administration of China on September 4, 2018, for the first-line treatment of patients with unresectable hepatocellular carcinoma who have not received systematic treatment before. Up to February 2023, Lenvatinib has been listed in China for more than 4 years, accumulating a series of post-marketing clinical research evidences. Based on the clinical practice before and after the launch of lenvatinib and referring to the clinical experience of other anti-angiogenesis inhibitors, domestic multidisciplinary experts and scholars adopt the Delphi method to formulate the Chinese Expert Guidance on Overall Application of Lenvatinib in Hepatocellular Carcinoma after repeated discussions and revisions, in order to provide reference for reasonable and effective clinical application of lenvatinib for clinicians.

Personalized music therapy combined with medication as treatment for tinnitus

OBJECTIVE

This study aimed to investigate the effects of personalized music therapy in combination with medication as a treatment for tinnitus.

PATIENTS AND METHODS

We retrospectively analyzed a total of 200 patients who were admitted to the Department of Otorhinolaryngology in our hospital from June 2018 to June 2019, with tinnitus as their primary complaint. Patients were divided into four groups based on their individual treatment methods: medication group (patients received medication only, n=40), tinnitus masking (TM) group (patients received medication plus TM, n=38), tinnitus re-training (TRT) group (patients received medication plus TRT, n=35), and personalized group (patients received medication plus personalized music therapy, n=30). The pure-tone audiometry (PTA), loudness visual analogue scale (VAS), and tinnitus handicap inventory (THI) for each patient were analyzed.

RESULTS

There were statistically significant differences in the THI and VAS scores of all groups before and after treatment (p<0.05). Following nine and twelve months of treatment, the THI and VAS scores of the TRT group and the personalized group were significantly lower than those of the other two groups (p<0.05). The THI and VAS scores of the personalized group were significantly lower than those of the TRT group (p<0.05). Additionally, THI and VAS scores were statistically different at various measurement time points in each group (p<0.05). The clinical effective rate (85.37%) of the personalized group was higher than that of the other three groups (p<0.05).

CONCLUSIONS

TM, TRT, or personalized music therapy, when combined with medication, are effective in treating patients with tinnitus. Among these methods, personalized music therapy may be the superior treatment after nine months of treatment.

[Prevalence rate and risk factor analysis of nonalcoholic fatty liver disease in 115 female patients with schizophrenia]

Objective: To investigate the incidence rate and risk factors of nonalcoholic fatty liver disease (NAFLD) in patients with schizophrenia (SCZ). Methods: The incidence rate of NAFLD in 115 females with SCZ over 40 years of age with complete clinical data was analyzed with the consent of the Ethics Committee of Nantong Fourth People's Hospital. A physical examination report of healthy subjects (n = 95, female, age 40 years old or older) was taken as the control group. Natural language processing technology was used to extract relevant data from the patient's electronic medical record system. Body mass index, alanine aminotransferase, triglycerides, low-density lipoprotein, leptin, and adiponectin were used to establish a human NAFLD-related model. Logistic regression analysis was used to evaluate the psychiatric symptoms, and physiological and biochemical indexes for the predictive value of NAFLD in female patients with SCZ. Results: The prevalence of NAFLD was significantly higher in the SCZ group (55.7%, 64/115) than that in the control group (26.3%, 25/95) (χ (2) = 18.335, P < 0.001). The prediction model showed that age, alanine aminotransferase, triglycerides, low-density lipoprotein, leptin, adiponectin, and body mass index were significantly correlated with NAFLD in females with SCZ. In the natural language processing search language model, arousal intensity (movements: uncontrolled running behavior) and emotional apathy were strongly linked to female patients with SCZ with NAFLD. Age, alanine aminotransferase, triglycerides, low-density lipoprotein, leptin, and body mass index were risk factors for SCZ to develop NAFLD, and adiponectin levels and uncontrolled running behavior were protective factors. Conclusion: The incidence rate of NAFLD is high in middle-aged and elderly females with SCZ. Natural language processing can help to automatically identify the risk factors for SCZ combined with NAFLD and has predictive and auxiliary diagnostic value.

[Early antiviral treatment response in HBeAg-positive chronic HBV infected-patients with high viral load and normal ALT]

The diagnosis and treatment rates of hepatitis B virus (HBV) infection in China in 2020 were 22.1% and 15.0%, respectively, according to the Polaris Observatory HBV Collaborators report. This is still far below the World Health Organization's 2030 hepatitis B elimination target (90% and 80%, respectively, for the diagnosis and treatment rates). Although China has promulgated and implemented a series of policies to eliminate the hepatitis B virus, there are still many HBV infected patients who need to be detected and treated. It has been contoversial whether HBeAg-positive chronic HBV infected-patients with high viral load and normal alanine aminotransferase (ALT), also known as the "immune-tolerant phase," should receive anti-HBV therapy. Hepatologists should pay attention to the patient population known as "immune tolerant," as well as the continuous accumulation of evidence-based medical evidence for early antiviral therapy response. The current focus is on discussing the pros and cons of receiving and recommending anti-HBV therapy at this time for the management of these patients.

Suppression of microRNA168 enhances salt tolerance in rice (Oryza sativa L.)

BACKGROUND

Rice is a salt-sensitive crop. Complex gene regulatory cascades are likely involved in salinity stress in rice roots. microRNA168 (miR168) is a conserved miRNA among different plant species. It in-directly regulates the expression of all miRNAs by targeting gene ARGONAUTE1(AGO1). Short Tandem Target Mimic (STTM) technology is an ideal approach to study miRNA functions by in-activating mature miRNA in plants.

RESULTS

In this study, rice miR168 was inactivated by STTM. The T3 generation seedlings of STTM168 exhibited significantly enhanced salt resistance. Direct target genes of rice miR168 were obtained by in silico prediction and further confirmed by degradome-sequencing. PINHEAD (OsAGO1), which was previously suggested to be a plant abiotic stress response regulator. RNA-Seq was performed in root samples of 150mM salt-treated STTM168 and control seedlings. Among these screened 481 differentially expressed genes within STTM168 and the control, 44 abiotic stress response related genes showed significant difference, including four known salt-responsive genes.

CONCLUSION

Based on sequencing and qRT-PCR, a "miR168-AGO1-downstream" gene regulation model was proposed to be responsible for rice salt stress response. The present study proved miR168-AGO1 cascade to play important role in rice salinity stress responding, as well as to be applied in agronomic improvement in further.

[Regulatory mechanism and potential value of circular RNA in nonalcoholic fatty liver disease progression]

Nonalcoholic fatty liver disease (nonalcoholic fatty liver disease, NAFLD) or metabolic-associated fatty liver disease, has become the most common chronic liver disease worldwide. In recent years, the relationship between NAFLD and non-coding RNA (ncRNA) has attracted the attention of basic and clinical researchers. Circular RNA (circRNA) is a lipid metabolism-related non-coding RNA (ncRNA) that is highly conserved in eukaryotic cells and resembles but differs from linear ncRNAs at their 5'- and 3'-terminal ends. With tissue-specific and steady expression of endogenous ncRNA, miRNA binding sites are contained on closed and circular nucleoside chains, forming the circRNA-miR-mRNA axis or network with proteins, competing with endogenous RNA sponge-like mechanisms, playing a role in inhibiting or promoting the expression of related target genes, and participating in the progression of NAFLD. This paper reviews the circRNA regulatory mechanism, detection technology, and potential clinical value in NAFLD.

[Progress in research of Clostridium perfringens toxin]

Clostridium perfringens can produce many kinds of toxins and hydrolase, causing gas gangrene, enteritis and enterotoxemia in both human and animals. It is known that C. perfringens can produce more than 20 toxins and hydrolases. The different toxin types are associated with specific disease types. At present, molecular toxin-typing method by PCR has replaced the traditional serological typing method. In this study, we systematically summarize the types, basic characteristics, pathogenic mechanism and the relationship with disease of C. perfringens toxins to provide evidence for the establishment of rapid detection method, immune antigen screening, antibody preparation and research of related pathogenic mechanism.

[Analysis of upper airway morphology and laryngopharyngeal reflux in obese patients with OSA]

Objective: To investigate the morphological characteristics of upper airway and laryngopharyngeal reflux in obese patients with obstructive sleep apnea (OSA). Methods: A retrospective analysis was performed on the clinical data of 284 adult patients who underwent polysomnography (PSG) from April 2020 to April 2021 in the Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, including 83 males and 201 females, aged (32.70±7.74) years. Patients were divided into obese group (n=234) and non-obese group (n=50) according to body mass index (BMI). Patients were divided into mild OSA group, moderate OSA group, severe OSA group and extremely severe OSA group by PSG.The results of sleepiness and laryngopharyngeal reflux questionnaire, nasolaryngoscopy and polysomnography were compared in each group. SPSS (version 22.0) software was used in data analysis. Results: Compared with the non-obese OSA group, the lymphoid hyperplasia of tongue root was more heavy in the obese OSA group, and Mueller's maneuver showed that the left-right lateral collapse of the velopharyngeal plane was more serious. Meanwhile, the scores of reflux symtom index (RSI) and reflux finding score (RFS) in the obese OSA group were significantly increased, and the scores of RSI and RFS increased with the increase of OSA severity. The main respiratory events in obese patients with OSA were obstructive hypopnea, their apnea-hypopnea indices(AHI) during REM (AHI_REM) was significantly higher than non-REM (AHI_NREM), and they had lower average blood oxygen saturation. Yet, there was no significant difference in the lowest blood oxygen saturation between the two groups. Conclusions: Our study suggests that lateral pharyngeal wall stenosis in velopharyngeal plane and the lymphoid hyperplasia of tongue root in glossopharyngeal plane occurs more frequently in obese patients with OSA. Laryngopharyngeal reflux is significantly increased in obese patients, and OSA increases laryngopharyngeal reflux in obese patients.

Aligning tumor mutational burden (TMB) quantification across diagnostic platforms: phase II of the Friends of Cancer Research TMB Harmonization Project

BACKGROUND

Tumor mutational burden (TMB) measurements aid in identifying patients who are likely to benefit from immunotherapy; however, there is empirical variability across panel assays and factors contributing to this variability have not been comprehensively investigated. Identifying sources of variability can help facilitate comparability across different panel assays, which may aid in broader adoption of panel assays and development of clinical applications.

MATERIALS AND METHODS

Twenty-nine tumor samples and 10 human-derived cell lines were processed and distributed to 16 laboratories; each used their own bioinformatics pipelines to calculate TMB and compare to whole exome results. Additionally, theoretical positive percent agreement (PPA) and negative percent agreement (NPA) of TMB were estimated. The impact of filtering pathogenic and germline variants on TMB estimates was assessed. Calibration curves specific to each panel assay were developed to facilitate translation of panel TMB values to whole exome sequencing (WES) TMB values.

RESULTS

Panel sizes >667 Kb are necessary to maintain adequate PPA and NPA for calling TMB high versus TMB low across the range of cut-offs used in practice. Failure to filter out pathogenic variants when estimating panel TMB resulted in overestimating TMB relative to WES for all assays. Filtering out potential germline variants at >0% population minor allele frequency resulted in the strongest correlation to WES TMB. Application of a calibration approach derived from The Cancer Genome Atlas data, tailored to each panel assay, reduced the spread of panel TMB values around the WES TMB as reflected in lower root mean squared error (RMSE) for 26/29 (90%) of the clinical samples.

CONCLUSIONS

Estimation of TMB varies across different panels, with panel size, gene content, and bioinformatics pipelines contributing to empirical variability. Statistical calibration can achieve more consistent results across panels and allows for comparison of TMB values across various panel assays. To promote reproducibility and comparability across assays, a software tool was developed and made publicly available.

[Clinical analysis of 16 cases of pulmonary epithelioid hemangioendothelioma]

Objective: To improve the diagnosis and treatment of pulmonary epithelioid hemangioendothelioma (P-EHE). Methods: Sixteen patients diagnosed with P-EHE in Fuzhou Pulmonary Hospital of Fujian Province from January 2009 to July 2020 were collected. Their gender, age, imaging findings, pathological characteristics, treatment protocols, survival and other clinical data were summarized and analyzed. Results: The ratio of male to female among the 16 patients was 1∶1; and the average age of onset was 47.75 years. Most cases of PEHE (9/16) were found by physical examination, while some cases developed respiratory symptoms such as cough, sputum, shortness of breath, hemoptysis, chest pain, etc. (7/16). In most patients the lesions were localized to the lungs (11/16), while bone metastasis (1/16), lymph node metastasis (1/16), and pleural metastasis (4/16) also occurred. The pathological tissues were obtained mainly through surgical thoracoscopy. Chest CT images showed multiple nodules in both lungs, with most of the nodules less than 2.0 cm in diameter, and calcifications were seen, while solitary nodules and masses were rare, and pleural metastases could be manifested as pleural thickening and pleural effusion. The pathological findings were well-defined eosinophilic nodules with irregularly arranged nest-like structures. Those eosinophilic nodules had few central cells and abundant peripheral cells, which extended into the alveolar cavity like papillae. The tumor cells were epithelioid with small atypia, and vacuoles and red blood cells could be seen in the cytoplasm of individual tumor cells. Immunohistochemically, the tumor cells were positive to CD34, CD31, Factor Ⅷ andvimentin (VIM). Follow-up of 0.5 to 11 years showed that four patients died, two lost to follow-up, and the rest of the patients were in good condition, with a median overall survival (OS) of 4.58 years. Conclusions: PEHE is a rare low-grade lung tumor with no specific clinical manifestations. It can be diagnosed with chest imaging and pathological immunohistochemistry. Moreover, there is currently no standard treatment for PEHE, and most patients have a good prognosis.

Changes in colorectal cancer incidence by site and age from 1973 to 2015: a SEER database analysis

Previous studies have reported incidence and mortality declines for colorectal cancer (CRC). We evaluated recent temporal trends of colorectal cancer in the United States for the last 4 decades. Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified primary CRCs diagnosed between 1973 and 2015. Temporal changes were evaluated by 6-year time periods. Age-adjusted incidence rates and annual percentage change (APC) for CRC were calculated by site and gender. Age-standardized relative survival rates were also evaluated. We identified 878,632 CRC patients, 51% of whom were men. For both genders, the proportions of new diagnoses of right-sided colon cancer (RCC) remained relatively stable, with the APC of - 0.8 and - 0.6 for the male and the female, respectively. There was a relative increase in RCC for the younger aged group (< 49 years). In contrast, the proportions of left-sided colon cancer (LCC) and rectosigmoid-cancer (RSC) decreased significantly over time. For those aged 0-49, the age adjusted incidence rates showed a small increase (in both genders), whereas age-adjusted incidence rates declined for those aged 50-64 and > 65 (in both genders). Our study showed near significance in the decline of CRC mortality rates in this population, except the 1-year age-standardized survival of LCC and RSC, and the 5-year age-standardized RCC in females. There was a significant increase in RCC for the younger aged group (< 49 years). In contrast, the proportions of LCC and RSC decreased significantly over time.

Tumor-derived lactate inhibit the efficacy of lenvatinib through regulating PD-L1 expression on neutrophil in hepatocellular carcinoma

BACKGROUND

Neutrophils play a controversial role in tumor development. The function of programmed cell death-1 ligand (PD-L1⁺) neutrophils, however, may inhibit the cytotoxicity of anti-tumor immunity. In this study, we elucidate the stimulators of PD-L1⁺ neutrophils in tumor microenvironment (TME) and explore the optimal combination to enhance the effect of lenvatinib by inhibiting PD-L1⁺ neutrophils in hepatocellular carcinoma.

METHODS

Neutrophil infiltration after lenvatinib treatment was examined with RNA sequencing and multicolor flow cytometry analysis in patient samples, subcutaneous and orthotopic mouse models. Neutrophils and T cells were isolated from peripheral blood and tumor tissues and purified with magnetic beads for cytotoxicity assay. Metabolites and cytokines were detected by a biochemical analyzer manufactured by Yellow Springs Instrument (YSI) and proteome profiler cytokines array. In vitro screening of pathway inhibitors was used to identify possible candidates that could reduce PD-L1⁺ neutrophil infiltration. Further in vivo assays were used for verification.

RESULTS

Lenvatinib increased neutrophil recruitment by inducing CXCL2 and CXCL5 secretion in TME. After entering TME, neutrophils polarized toward N2 phenotype. PD-L1 expression was simultaneously upregulated. Thus, lenvatinib efficacy on tumor cells hindered. The increasing PD-L1⁺ neutrophils positively corelated with a suppressive T cell phenotype. Further investigation indicated that JAK/STAT1 pathway activated by immune-cell-derived interferon γ and MCT1/NF-kB/COX-2 pathway activated by high concentrations of tumor-derived lactate could induce PD-L1⁺ neutrophils. The latter could be significantly inhibited by COX-2 inhibitor celecoxib. Further in vivo assays verified that Celecoxib decreased the survival of lactate-stimulated PD-L1⁺ neutrophil and promoted the antitumor effect of lenvatinib.

CONCLUSIONS

PD-L1⁺ neutrophils decrease T cell cytotoxicity. Tumor-derived lactate induces PD-L1 expression on neutrophils via MCT1/NF-κB/COX-2 pathway. Thus, COX-2 inhibitor could reduce PD-L1⁺ neutrophil and restore T cell cytotoxicity. This may provide a potent addition to lenvatinib.

Risk factors and prevention of postoperative pancreatic fistula after insulinoma enucleation:a retrospective study from a high-volume center

BACKGROUND/OBJECTIVES

Enucleation is an effective surgical method to treat pancreatic insulinoma, however, the incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) is high. We aim to investigate the risk factors for CR-POPF which have not been well characterized and develop effective methods to prevent CR-POPF after enucleation.

METHODS

This retrospective cohort study included 161 patients diagnosed with insulinoma from June 2016 to July 2020 in Peking Union Medical College Hospital. The risk factors for CR-POPF were evaluated and the role of prophylactic pre-operative pancreatic stent to prevent the occurrence of CR-POPF after enucleation of pancreatic insulinoma were explored.

RESULTS

A cohort of 161 insulinoma cases were reviewed. The CT or MRI imaging reports could be tracked in 108 cases. A total of 96 patients underwent surgery, while 81 experienced pancreatic enucleation. Univariate and multivariate analyses showed that the distance from insulinoma to the main pancreatic duct (MPD) ≤2 mm was an independent risk factor for CR-POPF (p = 0.003, OR = 6.011, 95% Cl 1.852-19.512). The pre-operative pancreatic stent substantially reduced the incidence of CR-POPF in patients with tumor located in proximity to (distance ≤2 mm) the MPD (CR-POPF of the stented group vs the non-stented group: 37.5% vs 71.4%, p = 0.028).

CONCLUSIONS

The distance from insulinoma to MPD ≤2 mm is a predictive factor for CR-POPF after enucleation. Pancreatic duct stenting may benefit patients with insulinoma in proximity to the MPD by enabling a lower CR-POPF rate, so it should be considered before the enucleation of the insulinoma in proximity to the MPD (distance ≤2 mm).