Salvage camrelizumab for an intractable NK/T cell lymphoma patient with two instances of intestinal perforation: a case report and literature review

BACKGROUND

The prognosis of natural killer/T cell lymphoma (NKTCL) with multifocal small intestine involvement complicated by intestinal perforation is extremely poor. There is no evidence-based treatment strategy for this intractable condition.

CASE PRESENTATION

A 30-year-old male was admitted to our hospital in April 2017 and presented with recurrent fever for three months and multiple painless subcutaneous nodules in the abdominal wall. An excision biopsy of the subcutaneous nodules in the abdominal wall revealed NKTCL. The patient was diagnosed with stage IVB NKTCL with skin and multifocal small intestinal involvement according to the imaging results. The first intestinal perforation occurred due to tumor infiltration before the initial treatment. The second intestinal perforation occurred after receiving two cycles of chemotherapy with a modified SMILE regimen. The histone deacetylase inhibitor (HDACi) chidamide was administered as a single-agent therapy after recovery from the second intestinal perforation. Complete remission was achieved. Unfortunately, five months later, the patient was confirmed to have relapsed and received the salvage chemotherapy. The patient suffered from disease progression again after the fourth cycle of chemotherapy. At this point, from May 29, 2018, the patient started to receive injections of the anti-programmed death 1 (PD-1) antibody camrelizumab as a salvage treatment. Two months after the initial anti-PD-1 antibody camrelizumab injection, the response was partial remission. Disease progression was confirmed in March 2021, with a progression-free survival time of 34 months.

CONCLUSIONS

NKTCL patients with multifocal small intestine involvement have a high risk of intestinal perforation. The possible etiologies of bowel perforation include tumor infiltration, tumor necrosis in response to therapy, and acute inflammation. The anti-PD-1 antibody camrelizumab may be a new candidate agent for treating this type of intractable NKTCL. Further observations are necessary to identify the efficacy and safety of new agents in the future.

Inhibition of Wnt/β-catenin signaling upregulates Nav 1.5 channels in Brugada syndrome iPSC-derived cardiomyocytes

The voltage-gated Na_v 1.5 channels mediate the fast Na⁺ current (I_Na ) in cardiomyocytes initiating action potentials and cardiac contraction. Downregulation of I_Na , as occurs in Brugada syndrome (BrS), causes ventricular arrhythmias. The present study investigated whether the Wnt/β-catenin signaling regulates Na_v 1.5 in human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). In healthy male and female iPSC-CMs, activation of Wnt/β-catenin signaling by CHIR-99021 reduced (p < 0.01) both Na_v 1.5 protein and SCN5A mRNA. In iPSC-CMs from a BrS patient, both Na_v 1.5 protein and peak I_Na were reduced compared to those in healthy iPSC-CMs. Treatment of BrS iPSC-CMs with Wnt-C59, a small-molecule Wnt inhibitor, led to a 2.1-fold increase in Na_v 1.5 protein (p = 0.0005) but surprisingly did not affect SCN5A mRNA (p = 0.146). Similarly, inhibition of Wnt signaling using shRNA-mediated β-catenin knockdown in BrS iPSC-CMs led to a 4.0-fold increase in Na_v 1.5, which was associated with a 4.9-fold increase in peak I_Na but only a 2.1-fold increase in SCN5A mRNA. The upregulation of Na_v 1.5 by β-catenin knockdown was verified in iPSC-CMs from a second BrS patient. This study demonstrated that Wnt/β-catenin signaling inhibits Na_v 1.5 expression in both male and female human iPSC-CMs, and inhibition of Wnt/β-catenin signaling upregulates Na_v 1.5 in BrS iPSC-CMs through both transcriptional and posttranscriptional mechanisms.

Incidence rate and risk factors of ventilator-associated pneumonia in patients with traumatic brain injury: a systematic review and meta-analysis of observational studies

Background

Ventilator-associated pneumonia is a common complication of traumatic brain injury (TBI) patients, causing great harm to the life, health and society of patients. It is important to understand the risk factors related to ventilator-associated pneumonia for infection monitoring and control of patients. However, there are still some controversies about the risk factors in previous studies. Therefore, the purpose of this study was to explore the incidence and risk factors of ventilator-associated pneumonia in patients with TBI.

Methods

Two independent researchers selected literature collected by systematically searching databases including PubMed, Ovid, Embase, and ScienceDirect using medical subject headings. The primary end points of the included literature were extracted, and the Cochrane Q test and I² statistic were used to evaluate the heterogeneity between studies. The random effects model based on the restricted maximum likelihood method and the fixed effects model based on the reverse variance method were used to calculate and combine the relative risk or mean difference of relevant indicators. The publication bias was evaluated with the funnel plot and Egger test. All results were considered statistically significant at P<0.05.

Results

A total of 11 articles were included in this study for meta-analysis, and a total of 2,301 patients with TBI were included. The incidence of ventilator-associated pneumonia in TBI patients was approximately 42% (95% CI: 32-53%). Tracheotomy significantly increased the risk of ventilator-associated pneumonia in patients with TBI [relative risk (RR) =3.71; 95% CI: 1.48-6.94; P<0.05]; the use of prophylactic antibiotics could significantly reduce the risk of ventilator-associated pneumonia in patients with TBI. The risk of pneumonia (RR =0.53; 95% CI: 0.18-0.88; P<0.05); compared with female patients, male patients with TBI had a significantly higher risk (about 46%) of ventilator-associated pneumonia (RR =1.46; 95% CI: 1.13-1.79; P<0.05).

Conclusions

The risk of ventilator-associated pneumonia in patients with TBI is about 42%. Posttracheotomy and mechanical ventilation are risk factors for ventilator-associated pneumonia, while prophylactic use of antibiotics is a protective factor in the development of ventilator-associated pneumonia.

Aldehyde Olefination with Arylboroxines Enabled by Binary Rhodium Catalysis

A rhodium-catalyzed olefination of aliphatic aldehydes with arylboroxines is described. The simple rhodium(I) complex [Rh(cod)OH]₂ without any external ligands or additives is able to catalyze the reaction in air and neutral conditions, allowing the construction of aryl olefins in an efficient manner with a good functional group tolerance. The mechanistic investigation illustrates that the binary rhodium catalysis is the key for the transformation, which involves a Rh(I)-catalyzed 1,2-addition and a Rh(III)-catalyzed elimination.

The Role of MAP3K1 in the Development of the Female Reproductive Tract

Mitogen-Activated Protein 3 Kinase 1 (MAP3K1) is a dynamic signaling molecule with a plethora of cell-type specific functions, most of which are yet to be understood. Here we describe a role for MAP3K1 in the development of female reproductive tract (FRT). MAP3K1 kinase domain-deficient ( Map3k1 ^ΔKD ) females exhibit imperforate vagina, labor failure, and infertility. These defects correspond to a shunted Müllerian duct (MD), the principle precursor of the FRT, in embryos, while they manifest as a contorted caudal vagina with abrogated vaginal-urogenital sinus fusion in neonates. In epithelial cells, MAP3K1 acts through JNK and ERK to activate WNT, yet in vivo MAP3K1 is crucial for WNT activity in mesenchyme associated with the caudal MD. Expression of Wnt7b is high in wild type, but low in Map3k1 knockout MD epithelium and MAP3K1-deficient keratinocytes. Correspondingly, conditioned media derived from MAP3K1-competent epithelial cells activate TCF/Lef-luciferase reporter in fibroblasts, suggesting that MAP3K1-induced factors released from epithelial cells trans-activate WNT signaling in fibroblasts. Our results reveal a temporal-spatial and paracrine MAP3K1-WNT crosstalk contributing to MD caudal elongation and FRT development.

Highlights

MAP3K1 deficient female mice exhibit imperforate vagina and infertilityLoss of MAP3K1 kinase activity impedes Müllerian duct (MD) caudal elongation and fusion with urogenital sinus (UGS) in embryogenesisThe MAP3K1-MAPK pathway up-regulates WNT signaling in epithelial cellsMAP3K1 deficiency down-regulates Wnt7b expression in the MD epithelium and prevents WNT activity in mesenchyme of the caudal MD.

Ni-Catalyzed Tunable Enantioconvergence and Kinetic Resolution in the Coupling of Tertiary Cyclobutenols with Arylboroxines

We herein discover that a nickel catalytic system with a modified SPINOL (1,1'-spirobiindane-7,7'-diol)-phosphoramidite as the chiral ligand can enable the coupling reaction between tertiary cyclobutenols and arylboroxines to occur in an enantioconvergent manner, providing cyclobutenes with an all-carbon quaternary stereocenter in good yields (up to 84% yield) with excellent enantioselectivities (up to >99.9% ee). Moreover, the catalytic system can be applied in the kinetic resolution of cyclobutenols under slightly modified conditions, giving enantioenriched tertiary cyclobutenols with an s factor up to > 200. The reaction employs a free hydroxyl in a strained-ring system as the leaving group without additional activation and can render the strained-ring untouched. Preliminary mechanistic studies reveal that the inherent discrepant reactivity of the two enantiomers is the key to achieve the controllable enantioconvergent and kinetic resolution process.

[HSDL2 overexpression promotes rectal cancer progression by regulating cancer cell cycle and promoting cell proliferation]

OBJECTIVE

To analyze the expression of hydroxysteroid dehydrogenase like 2 (HSDL2) in rectal cancer tissues and the effect of changes in HSDL2 expression level on proliferation of rectal cancer cells.

METHODS

Clinical data and tissue samples of 90 patients with rectal cancer admitted to our hospital from January 2020 to June 2022 were collected from the prospective clinical database and biological specimen database. The expression level of HSDL2 in rectal cancer and adjacent tissues was detected by immunohistochemistry, and based on the median level of HSDL2 expression, the patients were divided into high expression group (n=45) and low expression group (n=45) for analysis the correlation between HSDL2 expression level and the clinicopathological parameters. GO and KEGG enrichment analyses were performed to explore the role of HSDL2 in rectal cancer progression. The effects of changes in HSDL2 expression levels on rectal cancer cell proliferation, cell cycle and protein expressions were investigated in SW480 cells with lentivirus-mediated HSDL2 silencing or HSDL2 overexpression using CCK-8 assay, flow cytometry and Western blotting.

RESULTS

The expressions of HSDL2 and Ki67 were significantly higher in rectal cancer tissues than in the adjacent tissues (P < 0.05). Spearman correlation analysis showed that the expression of HSDL2 protein was positively correlated with Ki67, CEA and CA19-9 expressions (P < 0.01). The rectal cancer patients with high HSDL2 expressions had significantly higher likelihood of having CEA ≥5 μg/L, CA19-9 ≥37 kU/L, T3-4 stage, and N2-3 stage than those with a low HSDL2 expression (P < 0.05). GO and KEGG analysis showed that HSDL2 was mainly enriched in DNA replication and cell cycle. In SW480 cells, HSDL2 overexpression significantly promoted cell proliferation, increased cell percentage in S phase, and enhanced the expression levels of CDK6 and cyclinD1 (P < 0.05), and HSDL2 silencing produced the opposite effects (P < 0.05).

CONCLUSION

The high expression of HSDL2 in rectal cancer participates in malignant progression of the tumor by promoting the proliferation and cell cycle progress of the cancer cells.

[Silencing RAB27a inhibits proliferation, invasion and adhesion of triple-negative breast cancer cells]

OBJECTIVE

To investigate the effect of inhibition of RAB27 protein family, which plays a pivotal role in exosome secretion, on biological behaviors of triple-negative breast cancer cells.

METHODS

Quantitative real-time PCR and Western blotting were used to examine the expressions of RAB27 family and exosome secretion in 3 triple-negative breast cancer cell lines (MDA-MB-231, MDA-MB-468, and Hs578T) and a normal breast epithelial cell line (MCF10A). The effect of small interfering RNA (siRNA)-mediated silencing of RAB27a and RAB27b on exosome secretion in the 3 breast cancer cell lines was detected using Western blotting, and the changes in cell proliferation, invasion and adhesion were evaluated.

RESULTS

Compared with normal breast epithelial cells, the 3 triple-negative breast cancer cell lines exhibited more active exosome secretion (P < 0.001) and showed significantly higher expressions of RAB27a and RAB27b at both the mRNA and protein levels (P < 0.01). Silencing of RAB27a in the breast cancer cells significantly down-regulated exosome secretion (P < 0.001), while silencing of RAB27b did not significantly affect exosome secretion. The 3 breast cancer cell lines with RAB27a silencing-induced down-regulation of exosome secretion showed obvious inhibition of proliferation, invasion and adhesion (P < 0.01) as compared with the cell lines with RAB27b silencing.

CONCLUSION

RAB27a plays central role in the exosome secretion in triple-negative breast cancer cells, and inhibiting RAB27a can inhibit the proliferation, invasion and adhesion of the cells.

LigBind: identifying binding residues for over 1000 ligands with relation-aware graph neural networks

Identifying the interactions between proteins and ligands is significant for drug discovery and design. Considering the diverse binding patterns of ligands, the ligand-specific methods are trained per ligand to predict binding residues. However, most of the existing ligand-specific methods ignore shared binding preferences among various ligands and generally only cover a limited number of ligands with a sufficient number of known binding proteins. In this study, we propose a relation-aware framework LigBind with graph-level pre-training to enhance the ligand-specific binding residue predictions for 1159 ligands, which can effectively cover the ligands with a few known binding proteins. LigBind first pre-trains a graph neural network-based feature extractor for ligand-residue pairs and relation-aware classifiers for similar ligands. Then, LigBind is fine-tuned with ligand-specific binding data, where a domain adaptive neural network is designed to automatically leverage the diversity and similarity of various ligand-binding patterns for accurate binding residue prediction. We construct ligand-specific benchmark datasets of 1159 ligands and 16 unseen ligands, which are used to evaluate the effectiveness of LigBind. The results demonstrate the LigBind's efficacy on the large-scale ligand-specific benchmark datasets, and generalizes well to unseen ligands. LigBind also enables accurate identification of the ligand-binding residues in the main protease, papain-like protease and the RNA-dependent RNA polymerase of SARS-CoV-2. The webserver and source codes of LigBind are available at http://www.csbio.sjtu.edu.cn/bioinf/LigBind/ and https://github.com/YYingXia/LigBind/ for academic use.

Diversified Synthesis of All-Carbon Quaternary gem-Difluorinated Cyclopropanes via Copper-Catalyzed Cross-Coupling

The construction of all-carbon quaternary centers in small-ring systems is important but challenging in organic synthesis. Herein, by taking gem-difluorocyclopropyl bromides (DFCBs) as a type of general and versatile building block, we developed a practical method for building all-carbon quaternary centers in gem-difluorinated cyclopropanes (DFCs). The reaction relies on the involvement of a gem-difluorocyclopropyl radical intermediate, which can couple with a wide range of nucleophiles under copper catalysis.

Silencing of STE20-type kinase TAOK1 confers protection against hepatocellular lipotoxicity through metabolic rewiring

BACKGROUND

NAFLD has become the leading cause of chronic liver disease worldwide afflicting about one quarter of the adult population. NASH is a severe subtype of NAFLD, which in addition to hepatic steatosis connotes liver inflammation and hepatocyte ballooning. In light of the exponentially increasing prevalence of NAFLD, it is imperative to gain a better understanding of its molecular pathogenesis. The aim of this study was to examine the potential role of STE20-type kinase TAOK1 -a hepatocellular lipid droplet-associated protein-in the regulation of liver lipotoxicity and NAFLD etiology.

METHODS

The correlation between TAOK1 mRNA expression in liver biopsies and the severity of NAFLD was evaluated in a cohort of 62 participants. Immunofluorescence microscopy was applied to describe the subcellular localization of TAOK1 in human and mouse hepatocytes. Metabolic reprogramming and oxidative/endoplasmic reticulum stress were investigated in immortalized human hepatocytes, where TAOK1 was overexpressed or silenced by small interfering RNA, using functional assays, immunofluorescence microscopy, and colorimetric analysis. Migration, invasion, and epithelial-mesenchymal transition were examined in TAOK1-deficient human hepatoma-derived cells. Alterations in hepatocellular metabolic and pro-oncogenic signaling pathways were assessed by immunoblotting.

RESULTS

We observed a positive correlation between the TAOK1 mRNA abundance in human liver biopsies and key hallmarks of NAFLD (i.e., hepatic steatosis, inflammation, and ballooning). Furthermore, we found that TAOK1 protein fully colocalized with intracellular lipid droplets in human and mouse hepatocytes. The silencing of TAOK1 alleviated lipotoxicity in cultured human hepatocytes by accelerating lipid catabolism (mitochondrial β-oxidation and triacylglycerol secretion), suppressing lipid anabolism (fatty acid influx and lipogenesis), and mitigating oxidative/endoplasmic reticulum stress, and the opposite changes were detected in TAOK1-overexpressing cells. We also found decreased proliferative, migratory, and invasive capacity, as well as lower epithelial-mesenchymal transition in TAOK1-deficient human hepatoma-derived cells. Mechanistic studies revealed that TAOK1 knockdown inhibited ERK and JNK activation and repressed acetyl-CoA carboxylase (ACC) protein abundance in human hepatocytes.

CONCLUSIONS

Together, we provide the first experimental evidence supporting the role of hepatic lipid droplet-decorating kinase TAOK1 in NAFLD development through mediating fatty acid partitioning between anabolic and catabolic pathways, regulating oxidative/endoplasmic reticulum stress, and modulating metabolic and pro-oncogenic signaling.

The structural basis of the pH-homeostasis mediated by the Cl-/HCO3- exchanger, AE2

The cell maintains its intracellular pH in a narrow physiological range and disrupting the pH-homeostasis could cause dysfunctional metabolic states. Anion exchanger 2 (AE2) works at high cellular pH to catalyze the exchange between the intracellular HCO₃^- and extracellular Cl^-, thereby maintaining the pH-homeostasis. Here, we determine the cryo-EM structures of human AE2 in five major operating states and one transitional hybrid state. Among those states, the AE2 shows the inward-facing, outward-facing, and intermediate conformations, as well as the substrate-binding pockets at two sides of the cell membrane. Furthermore, critical structural features were identified showing an interlock mechanism for interactions among the cytoplasmic N-terminal domain and the transmembrane domain and the self-inhibitory effect of the C-terminal loop. The structural and cell-based functional assay collectively demonstrate the dynamic process of the anion exchange across membranes and provide the structural basis for the pH-sensitive pH-rebalancing activity of AE2.

Artificial intelligence annotated clinical-pathologic risk model to predict outcomes of advanced gastric cancer

Background

Gastric cancer with synchronous distant metastases indicates a dismal prognosis. The success in survival improvement mainly relies on our ability to predict the potential benefit of a therapy. Our objective is to develop an artificial intelligence annotated clinical-pathologic risk model to predict its outcomes.

Methods

In participants (n=47553) with gastric cancer of the surveillance, epidemiology, and end results program, we selected patients with distant metastases at first diagnosis, complete clinical-pathologic data and follow-up information. Patients were randomly divided into the training and test cohort at 7:3 ratio. 93 patients with advanced gastric cancer from six other cancer centers were collected as the external validation cohort. Multivariable analysis was used to identify the prognosis-related clinical-pathologic features. Then a survival prediction model was established and validated. Importantly, we provided explanations to the prediction with artificial intelligence SHAP (Shapley additive explanations) method. We also provide novel insights into treatment options.

Results

Data from a total 2549 patients were included in model development and internal test (median age, 61 years [range, 53-69 years]; 1725 [67.7%] male). Data from an additional 93 patients were collected as the external validation cohort (median age, 59 years [range, 48-66 years]; 51 [54.8%] male). The clinical-pathologic model achieved a consistently high accuracy for predicting prognosis in the training (C-index: 0.705 [range, 0.690-0.720]), test (C-index: 0.737 [range, 0.717-0.757]), and external validation (C-index: 0.694 [range, 0.562-0.826]) cohorts. Shapley values indicated that undergoing surgery, chemotherapy, young, absence of lung metastases and well differentiated were the top 5 contributors to the high likelihood of survival. A combination of surgery and chemotherapy had the greatest benefit. However, aggressive treatment did not equate to a survival benefit. SHAP dependence plots demonstrated insightful nonlinear interactive associations among predictors in survival benefit prediction. For example, patients who were elderly, or poor differentiated, or presence of lung or bone metastases had a worse prognosis if they undergo surgery or chemotherapy, while patients with metastases to liver alone seemed to gain benefit from surgery and chemotherapy.

Conclusion

In this large multicenter cohort study, we developed an artificial intelligence annotated clinical-pathologic risk model to predict outcomes of advanced gastric cancer. It could be used to discuss treatment options.

Synergistic effect of alloying on thermoelectric properties of two-dimensional PdPQ (Q = S, Se)

Hosts of 2D materials exist, yet few allow compositional and structural tailoring as the MQ₂ (M = Mo, W; Q = S, Se) family does, for which various structural superlattices have been synthesized. Using thorough first-principles calculations, we show how bonding hierarchy contributes to the structural resilience of 2D PdPQ and allows for full-range alloying of sulfur and selenium. Within the structural unit of Pd₂P₂Q₂, the covalently-bonded [P₂Q₂]^4- polyanions hold the structure together with their molecular-like P-P bonds while ionically bonded Pd-Qs allow the S/Se substitution. Here, the bonding hierarchy imparts superior electronic and structural features to the PdPQ monolayers. As such, the flat-and-dispersive valence band and the eight degenerate valleys of the conduction band benefit the p-type and n-type thermoelectricity of pristine PdPQ, which can be further enhanced by alloying. The high-entropy alloying synergistically suppresses the lattice heat transport from 75 to 30 W m^-1 K^-1 and increases the band degeneracy of PdPQ monolayers, resulting in an overall improvement in zT. Combining these features, in a naïve approach, results in a large zT approaching two for both p-type and n-type doping. However, accurate fully-fledged electron-phonon calculations rebut this promise, showing that at high temperatures, the increased electron scattering results in a stagnant power factor in the flat-and-dispersive valence band. Using a realistic first-principles scattering, we finally calculate the thermoelectric efficiency of PdPQ (Q = S, Se) and highlight the importance of an accurate estimation of electron relaxation time for thermoelectric predictions.