Evaluation of the American College of Surgeons risk calculator in hepatectomy for metastatic colorectal cancer in a Southeast Asian population.

PURPOSE: This study evaluated the accuracy of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) calculator in predicting outcomes after hepatectomy for colorectal cancer (CRC) liver metastasis in a Southeast Asian population. METHODS: Predicted and actual outcomes were compared for 166 patients undergoing hepatectomy for CRC liver metastasis identified between 2017 and 2022, using receiver operating characteristic curves with area under the curve (AUC) and Brier score. RESULTS: The ACS-NSQIP calculator accurately predicted most postoperative complications (AUC > 0.70), except for surgical site infection (AUC = 0.678, Brier score = 0.045). It also exhibited satisfactory performance for readmission (AUC = 0.818, Brier score = 0.011), reoperation (AUC = 0.945, Brier score = 0.002), and length of stay (LOS, AUC = 0.909). The predicted LOS was close to the actual LOS (5.9 vs. 5.0 days, P = 0.985). CONCLUSION: The ACS-NSQIP calculator demonstrated generally accurate predictions for 30-day postoperative outcomes after hepatectomy for CRC liver metastasis in our patient population.

Leptomeningeal metastasis of breast cancer during neo-adjuvant chemotherapy in a 38-year-old woman: a case report.

Background: Breast cancer accounts for 5% of the population who develop central nervous system metastasis, which is only second to the lung cancer. Breast cancer metastasis to the brain including parenchymal brain metastasis (BM) and leptomeningeal metastasis (LM). Compared with BM, LM is a more rare but aggressive metastatic diagnosis with poor outcome. Case Description: We reported a 38-year-old woman presented to the neurology department due to progressive headache for 1 month, accompanied with dizziness, nausea, vomiting and neck pain. During hospitalization, she experienced paroxysmal loss of consciousness twice. Five months prior to this visit, her first visit was diagnosed with breast cancer on the right side which was of triple-negative subtype and with homolateral axillary lymph node involvement by biopsy. After the clinician assessment she had received six cycles of TCb (docetaxel/carboplatin) neo-adjuvant chemotherapy. During the period of neo-adjuvant chemotherapy, she did not report the presence of severe neurological symptoms. Twenty days ago, she underwent right breast-conserving surgery and the postoperative evaluation was ypT1N3M0 stage and Miller-Payne grade 2. Head computed tomography (CT) scan and contrast-enhanced magnetic resonance imaging (MRI) didn't find typical brain imaging changes. No other signs of metastasis were seen in the CT examinations of the patient's chest and abdomen. Finally, lumbar puncture with cerebrospinal fluid (CSF) analysis showed the presence of malignant cells. Given the patient's clinical history and new neurologic symptoms, the diagnosis was LM from breast cancer. Various treatment modalities including intrathecal thiotepa, oral temozolomide (TMZ) and whole-brain radiation therapy (WBRT) had been used, but none of them showed significant benefit for survival. Conclusions: Breast cancer metastasis to the brain, especially LM, should be given sufficient vigilance and attention at the beginning of the diagnosis and treatment, particularly in triple-negative breast cancer patients who are at high risk. Symptoms of LM may be masked by the chemotherapy adverse effects. The results of MRI and CT may show negative results, thus lumbar puncture with CSF should be done promptly if LM is highly suspected in clinical practice. Early prevention, early detection and timely treatment are crucial according to the poor prognosis.

Interactions between MDSCs and the Autonomic Nervous System: Opportunities and Challenges in Cancer Neuroscience.

Myeloid-derived suppressor cells (MDSC) are a population of heterogeneous immune cells that are involved in precancerous conditions and neoplasms. The autonomic nervous system (ANS), which is composed of the sympathetic nervous system and the parasympathetic nervous system, is an important component of the tumor microenvironment that responds to changes in the internal and external environment mainly through adrenergic and cholinergic signaling. An abnormal increase of autonomic nerve density has been associated with cancer progression. As we discuss in this review, growing evidence indicates that sympathetic and parasympathetic signals directly affect the expansion, mobilization, and redistribution of MDSCs. Dysregulated autonomic signaling recruits MDSCs to form an immunosuppressive microenvironment in chronically inflamed tissues, resulting in abnormal proliferation and differentiation of adult stem cells. The two components of the ANS may also be responsible for the seemingly contradictory behaviors of MDSCs. Elucidating the underlying mechanisms has the potential to provide more insights into the complex roles of MDSCs in tumor development and lay the foundation for the development of novel MDSC-targeted anticancer strategies.

The trends of pediatric duodenal ulcer and predictors of recurrence.

BACKGROUND: Duodenal ulcer (DU) causes various symptoms in children. The prevalence of Helicobacter pylori (Hp)-associated DU has been reducing in some regions, yet the updated trend in Taiwan is unknown. Risk factors of DU recurrence have not been comprehensively investigated in children. METHODS: This retrospective study included children diagnosed with DU to evaluate the demographics, symptoms, diagnostics, treatment, and outcomes. Specific populations (infant, surgery required) were sorted for subgroup analysis. Predictors of DU recurrence was analyzed in patients who received endoscopic follow-ups. RESULTS: A total of 488 children were included. Most patients were male (72.5%), school-aged (11.3 ± 4.8 years old), and with varied underlying diseases in one-fifth. The annual incidences were around 3-5%, with a declining trend of case numbers and the Hp-positive proportion. Hp infection, concurrent gastric ulcer, perforation, and mortality were noted in 32.7%, 16%, 1.6%, and 1% of patients. Patients with or without Hp infection showed different clinical features but similar outcomes. The characteristics of subpopulations were depicted respectively. Male sex, lower Hb level, and perforation were independent risk factors associated with recurrence. CONCLUSIONS: Hp-positive DU seems to wane. Patients with male sex, lower Hb level, or perforation at diagnosis carried a higher risk of recurrence, which may warrant active surveillance and endoscopic follow-up.

Twenty years' experience of midgut malrotation and volvulus in a tertiary center in northern Taiwan: A retrospective study.

BACKGROUND: Early diagnosis and surgical intervention for midgut malrotation with bowel obstruction are crucial. We aimed to identify risk factors for adverse outcomes in infants with midgut malrotation and to develop a prediction model. METHODS: We reviewed the operation records of infants surgically diagnosed with midgut malrotation at Chang Gung Children's Medical Center between January 2000 and December 2020. Patients were classified into the poor-outcome group (PO) if they underwent bowel resection or experienced mortality; all others were categorized as the favorable-outcome group (FO). Data on demographics, initial presentations, laboratory results, radiographic or sonographic findings, maternal conditions, and outcomes were collected and analyzed. Fisher's exact test, the independent sample t-test, and the Mann-Whitney test were utilized for comparative analysis when suitable. RESULTS: The study included 103 infants. Eleven were in the PO group, and 92 were in the FO group. Initial presentations such as respiratory distress, poor activity, and shock status were notably more prevalent in the PO group. The INR, hemoglobin, HCO3, base excess, and aspartate transaminase values showed significant variation between the two groups. Multivariate analysis identified that lower hemoglobin (OR 0.677, p = 0.043) and higher AST (OR 1.036, p = 0.044) were independent predictors of adverse outcomes. An AST/Hb ratio of <3.78 demonstrated a high negative predictive value (98.6%) for an adverse outcome in midgut malrotation. CONCLUSIONS: Prompt diagnosis and surgical treatment of midgut malrotation are vital to prevent bowel resection or mortality. The independent predicting factors for poor outcomes include low hemoglobin and elevated AST levels.

Lung adenocarcinoma with EGFR L858R-K860I and L858R-L861F doublet mutations from which the L858R mutation is undetectable through the cobas EGFR mutation test v2.

In East Asia, epidermal growth receptor factor (EGFR) mutations are the most prevalent and important biomarkers for treating patients with advanced lung cancer. However, as L858R doublet mutations are rare, commercially available EGFR tests may yield false-negative results. To determine whether the L858R mutation of the L858R-K860I and L858R-L861F doublet mutations could be identified using different types of EGFR detection tests and to describe the clinical response of patients with lung cancer with L858R doublet mutations to EGFR tyrosine kinase inhibitors (TKI). Information and samples from four patients with L858R doublet mutations, including three with L858R-K860I and one with L858R-L861F, were retrospectively collected from the archives of our department. For each case, the clinical response to EGFR-TKI was retrieved from the medical records. Archived formalin-fixed paraffin-embedded blocks were subjected to Sanger sequencing, the cobas and Idylla EGFR tests, the IntelliPlex-LCP-DNA assay, and AmoyDx PLC panel. L858R mutations were all detected by Sanger sequencing and the Idylla EGFR test but missed by the cobas assay. The AmoyDx PLC detected L858R only in cases with L858R-K860I while the IntelliPlex-LCP-DNA assay detected L858R in the case with L858R-L861F. Additionally, three of the patients, who had measurable tumors, showed partial responses to afatinib and osimertinib. The L858R mutation associated with L858R-K860I and L858R-L861F doublet mutations could be detected using Idylla but not cobas EGFR tests. Using next-generation sequencing analysis should be considered after initial negative reports from the cobas test, because patients with L858R doublet mutations may benefit from EGFR-TKIs.

In situ fast self-assembled preparation of dandelion-like Cu(OH)2@Cu3(HHTP)2 with core-shell heterostructure arrays for electrochemical sensing of formaldehyde in food samples.

Formaldehyde is known to harm the respiratory, nervous, and digestive systems of people. In this paper, a novel dandelion-like electrocatalyst with core-shell heterostructure arrays were fast self-assembled prepared in situ using copper foam (CF) as support substrate and 2,3,6,7,10,11 hexahydroxy-triphenyl (HHTP) as ligand (Cu(OH)2@Cu3(HHTP)2/CF) by a simple two-step hydrothermal reaction. The 1D Cu(OH)2 nanorods "core" and the 2D π-conjugated conducting metal-organic frameworks (Cu3(HHTP)2cMOF) "shell" with remote delocalized electrons give the dandelion-like heterogeneous catalysts excellent electrochemical activity such as a large specific surface area, high conductivity and a fast electron transfer rate. The Cu(OH)2@Cu3(HHTP)2/CF exhibited excellent electrocatalytic performance for formaldehyde under alkaline conditions with a linear range of 0.2 µmol/L - 125 µmol/L and 125 µmol/L - 8 mmol/L, a detection limit as low as 15.9 nmol/L (S/N = 3), as well as good accuracy, consistency, and durability, and it effectively identified FA in food.

Multitask deep learning for prediction of microvascular invasion and recurrence-free survival in hepatocellular carcinoma based on MRI images.

BACKGROUND AND AIMS: Accurate preoperative prediction of microvascular invasion (MVI) and recurrence-free survival (RFS) is vital for personalised hepatocellular carcinoma (HCC) management. We developed a multitask deep learning model to predict MVI and RFS using preoperative MRI scans. METHODS: Utilising a retrospective dataset of 725 HCC patients from seven institutions, we developed and validated a multitask deep learning model focused on predicting MVI and RFS. The model employs a transformer architecture to extract critical features from preoperative MRI scans. It was trained on a set of 234 patients and internally validated on a set of 58 patients. External validation was performed using three independent sets (n = 212, 111, 110). RESULTS: The multitask deep learning model yielded high MVI prediction accuracy, with AUC values of 0.918 for the training set and 0.800 for the internal test set. In external test sets, AUC values were 0.837, 0.815 and 0.800. Radiologists' sensitivity and inter-rater agreement for MVI prediction improved significantly when integrated with the model. For RFS, the model achieved C-index values of 0.763 in the training set and ranged between 0.628 and 0.728 in external test sets. Notably, PA-TACE improved RFS only in patients predicted to have high MVI risk and low survival scores (p < .001). CONCLUSIONS: Our deep learning model allows accurate MVI and survival prediction in HCC patients. Prospective studies are warranted to assess the clinical utility of this model in guiding personalised treatment in conjunction with clinical criteria.

A novel hollow CuMn-PBA@NiCo-LDH nanobox for efficient detection of glucose in food.

Designing a rapid and sensitive glucose detection method is of great significance to public health. Herein, hollow CuMn-PBA@NiCo-LDH nanoboxes (CuMn-PBA@NiCo-LDH NBs) were prepared using acid etching, cation exchange, and reflux method. The modified electrode exhibited outstanding electrocatalytic performance for glucose oxidation due to the unique hollow nanostructure and synergistic effects. The CuMn-PBA@NiCo-LDH NBs electrode displayed excellent electrocatalytic oxidation activity for glucose in an alkaline solution. Under optimal conditions, the electrode achieved a wide linear range (0.0005-1 mmol L-1, and 1-7 mmol L-1) and high sensitivity (10,300 µA L/mmol cm-2 and 5310 µA L/mmol cm-2), with a limit of detection (LOD) of 19 nmol L-1. The feasibility of the sensor applied to the detection of glucose was verified in real food samples through spiked recovery experiments. This electrode material offers an alternative method for the non-enzymatic glucose sensors.

Factors affecting overall survival and disease-free survival after surgery for hepatocellular carcinoma: a nomogram-based prognostic model-a Western European multicenter study.

Few studies have assessed the clinical implications of the combination of different prognostic indicators for overall survival (OS) and disease-free survival (DFS) of resected hepatocellular carcinoma (HCC). This study aimed to evaluate the prognostic factors in HCC patients for OS and DFS outcomes and establish a nomogram-based prognostic model to predict the DFS of HCC. A multicenter, retrospective European study was conducted through the collection of data on 413 consecutive treated patients with a first diagnosis of HCC between January 2010 and December 2020. Univariate and multivariate Cox regression analyses were performed to identify all independent risk factors for OS and DFS outcomes. A nomogram prognostic staging model was subsequently established for DFS and its precision was verified internally by the concordance index (C-Index) and externally by calibration curves. For OS, multivariate Cox regression analysis indicated Child-Pugh B7 score (HR 4.29; 95% CI 1.74-10.55; p = 0.002) as an independent prognostic factor, along with Barcelona Clinic Liver Cancer (BCLC) stage ≥ B (HR 1.95; 95% CI 1.07-3.54; p = 0.029), microvascular invasion (MVI) (HR 2.54; 95% CI 1.38-4.67; p = 0.003), R1/R2 resection margin (HR 1.57; 95% CI 0.85-2.90; p = 0.015), and Clavien-Dindo Grade 3 or more (HR 2.73; 95% CI 1.44-5.18; p = 0.002). For DFS, multivariate Cox regression analysis indicated BCLC stage ≥ B (HR 2.15; 95% CI 1.34-3.44; p = 0.002) as an independent prognostic factor, along with multiple nodules (HR 2.04; 95% CI 1.25-3.32; p = 0.004), MVI (HR 1.81; 95% CI 1.19-2.75; p = 0.005), satellite nodules (HR 1.63; 95% CI 1.09-2.45; p = 0.018), and R1/R2 resection margin (HR 3.39; 95% CI 2.19-5.25; < 0.001). The C-Index of the nomogram, tailored based on the previous significant factors, showed good accuracy (0.70). Internal and external calibration curves for the probability of DFS rate showed optimal consistency and fit well between the nomogram-based prediction and actual observations. MVI and R1/R2 resection margins should be considered as significant OS and DFS predictors, while satellite nodules should be included as a significant DFS predictor. The nomogram-based prognostic model for DFS provides a more effective prognosis assessment for resected HCC patients, allowing for individualized treatment plans.

The impact of hospital volume on liver resection: A systematic review and Bayesian network meta-analysis.

BACKGROUND: This study aims to compare the outcomes of high-volume, medium-volume, and low-volume hospitals performing hepatic resections using a network meta-analysis. METHODS: A literature search until June 2023 was conducted across major databases to identify studies comparing outcomes in high-volume, medium-volume, and low-volume hospitals for liver resection. Bayesian network meta-analysis was conducted, and surface under cumulative ranking area values, odds ratio, and mean difference with 95% credible intervals were reported for postoperative mortality, failure-to-rescue, morbidity, length of stay, and hospital costs. RESULTS: Twenty studies comprising 248,707 patients undergoing liver resection were included. For the primary mortality outcome, overall and subgroup analyses were performed: group I: high-volume = 5 to 20 resections/year; group II: high-volume = 21 to 49 resections/year; group III: high-volume ≥50 resections/year. Results demonstrated a significant association between hospital volume and mortality (overall-high-volume versus medium-volume: odds ratio 0.66, 95% credible interval 0.49-0.87; high-volume versus low-volume: odds ratio 0.52, 95% credible interval 0.41-0.65; group I-high-volume versus low-volume: odds ratio 0.34, 95% credible interval 0.22-0.50; medium-volume versus low-volume: odds ratio 0.56, 95% credible interval 0.33-0.92; group II-high-volume versus low-volume: odds ratio 0.67, 95% credible interval 0.45-0.91), as well as length of stay (high-volume versus low-volume: mean difference -1.24, 95% credible interval -2.07 to -0.41), favoring high-volume hospitals. No significant difference was observed in failure-to-rescue, morbidity, or hospital costs across the 3 groups. CONCLUSION: This study supports a positive relationship between hospital volume and surgical outcomes in liver resection. Patients from high-volume hospitals experience superior outcomes in terms of lower postoperative mortality and shorter lengths of stay than medium-volume and low-volume hospitals.

Engineering the synthesis of unsaturated fatty acids by introducing desaturase improved the stress tolerance of yeast.

BACKGROUND: Yeast is often used to build cell factories to produce various chemicals or nutrient substances, which means the yeast has to encounter stressful environments. Previous research reported that unsaturated fatty acids were closely related to yeast stress resistance. Engineering unsaturated fatty acids may be a viable strategy for enhancing the stress resistance of cells. RESULTS: In this study, two desaturase genes, OLE1 and FAD2 from Z. rouxii, were overexpressed in S. cerevisiae to determine how unsaturated fatty acids affect cellular stress tolerance of cells. After cloning and plasmid recombination, the recombinant S. cerevisiae cells were constructed. Analysis of membrane fatty acid contents revealed that the recombinant S. cerevisiae with overexpression of OLE1 and FAD2 genes contained higher levels of fatty acids C16:1 (2.77 times), C18:1 (1.51 times) and C18:2 (4.15 times) than the wild-type S. cerevisiae pY15TEF1. In addition, recombinant S. cerevisiae cells were more resistant to multiple stresses, and exhibited improved membrane functionality, including membrane fluidity and integrity. CONCLUSION: These findings demonstrated that strengthening the expression of desaturases was beneficial to stress tolerance. Overall, this study may provide a suitable means to build a cell factory of industrial yeast cells with high tolerance during biological manufacturing. © 2023 Society of Chemical Industry.

Efficient and Targeted siRNA Delivery to M2 Macrophages by Smart Polymer Blends for M1 Macrophage Repolarization as a Promising Strategy for Future Cancer Treatment.

Cancer remains an issue on a global scale. It is estimated that nearly 10 million people succumbed to cancer worldwide in 2020. New treatment options are urgently needed. A promising approach is a conversion of tumor-promoting M2 tumor-associated macrophages (TAMs) as part of the tumor microenvironment to tumor-suppressive M1 TAMs by small interfering RNA (siRNA). In this work, we present a well-characterized polymeric nanocarrier system capable of targeting M2 TAMs by a ligand-receptor interaction. Therefore, we developed a blended PEI-based polymeric nanoparticle system conjugated with mannose, which is internalized after interaction with macrophage mannose receptors (MMRs), showing low cytotoxicity and negligible IL-6 activation. The PEI-PCL-PEI (5 kDa-5 kDa-5 kDa) and Man-PEG-PCL (2 kDa-2 kDa) blended siRNA delivery system was optimized for maximum targeting capability and efficient endosomal escape by evaluation of different polymer and N/P ratios. The nanoparticles were formulated by surface acoustic wave-assisted microfluidics, achieving a size of ∼80 nm and a zeta potential of approximately +10 mV. Special attention was given to the endosomal escape as the so-called bottleneck of RNA drug delivery. To estimate the endosomal escape capability of the nanocarrier system, we developed a prediction method by evaluating the particle stability via the inflection temperature. Our predictions were then verified in an in vitro setting by applying confocal microscopy. For cellular experiments, however, human THP-1 cells were polarized to M2 macrophages by cytokine treatment and validated through MMR expression. To show the efficiency of the nanoparticle system, GAPDH and IκBα knockdown was performed in the presence or absence of an MMR blocking excess of mannan. Cellular uptake, GAPDH knockdown, and NF-κB western blot confirmed efficient mannose targeting. Herein, we presented a well-characterized nanoparticle delivery system and a promising approach for targeting M2 macrophages by a mannose-MMR interaction.

Improvement of the viability of Tetragenococcus halophilus under acidic stress by forming the biofilm cell structure based on RNA-Seq and iTRAQ analyses.

BACKGROUND: Tetragenococcus halophilus is a halophilic lactic acid bacterium (LAB) isolated from soya sauce moromi. During the production of these fermented foods, acid stress is an inevitable environmental stress. In our previous study, T. halophilus could form biofilms and the cells in the biofilms exhibited higher cell viability under multiple environmental stresses, including acid stress. RESULTS: In this study, the effect of preformed T. halophilus biofilms on cell survival, cellular structure, intracellular environment, and the expression of genes and proteins under acid stress was investigated. The result showed that acid stress with pH 4.30 for 1.5 h reduced the live T. halophilus cell count and caused cellular structure damage. However, T. halophilus biofilm cells exhibited greater cell survival under acid stress than the planktonic cells, and biofilm formation reduced the damage of acid stress to the cell membrane and cell wall. The biofilm cells maintained a higher level of H+ -ATPase activity and intracellular ammonia concentration after acid stress. The RNA-Seq and iTRAQ technologies revealed that the genes and proteins associated with ATP production, the uptake of trehalose and N-acetylmuramic acid, the assembly of H+ -ATPase, amino acid biosynthesis and metabolism, ammonia production, fatty acid biosynthesis, CoA biosynthesis, thiamine production, and acetoin biosynthesis might be responsible for the stronger acid tolerance of T. halophilus biofilm cells together. CONCLUSION: These findings further explained the mechanisms that allowed LAB biofilm cells to resist environmental stress. © 2023 Society of Chemical Industry.

Integrated analysis reveals the potential of cluster of differentiation 86 as a key biomarker in high-grade glioma.

This study aimed to evaluate the potential of cluster of differentiation 86 (CD86) as a biomarker in high-grade glioma (HGG). The TCGA and TCIA databases were used to obtain the CD86 expression value, clinical data, and MRI images of HGG patients. Prognostic values were assessed by the Kaplan-Meier method, Receiver operating characteristic curve (ROC), Cox regression, logistic regression, and nomogram analyses. CD86-associated pathways were also explored. We found that CD86 was significantly upregulated in HGG compared with the normal group. Survival analysis showed a significant association between CD86 high expression and shorter overall survival time. Its independent prognostic value was also confirmed. These results suggested the possibility of CD86 as a biomarker in HGG. We also innovatively established 2 radiomics models with Support Vector Machine (SVM) and Logistic regression (LR) algorithms to predict the CD86 expression. The 2 models containing 5 optimal features by SVM and LR methods showed similar favorable performance in predicting CD86 expression in the training set, and their performance were also confirmed in validation set. These results indicated the successful construction of a radiomics model for non-invasively predicting biomarker in HGG. Finally, pathway analysis indicated that CD86 might be involved in the natural killer cell-mediated cytotoxicity in HGG progression.

Circular RNAs: biology and clinical significance of breast cancer.

Circular RNAs (circRNAs) are novel noncoding RNAs with covalently closed-loop structures that can regulate eukaryotic gene expression. Due to their stable structure, circRNAs are widely distributed in the cytoplasm and have important biological functions, including as microRNA sponges, RNA-binding protein conjugates, transcription regulators, and translation templates. Breast cancer is among the most common malignant cancers diagnosed in women worldwide. Despite the development of comprehensive treatments, breast cancer still has high mortality rates. Recent studies have unmasked critical roles for circRNAs in breast cancer as regulators of tumour initiation, progression, and metastasis. Further, research has revealed that some circRNAs have the potential for use as diagnostic and prognostic biomarkers in clinical practice. Herein, we review the biogenesis and biological functions of circRNAs, as well as their roles in different breast cancer subtypes. Moreover, we provide a comprehensive summary of the clinical significance of circRNAs in breast cancer. CircRNAs are believed to be a hot focus in basic and clinical research of breast cancer, and innovative future research directions of circRNAs could be used as biomarkers, therapeutic targets, or novel drugs.Abbreviations: CeRNA: Competitive endogenous RNA; ciRNA: Circular intronic RNA; circRNA: Circular RNA; EIciRNA: Exon-intron circRNA; EMT: Epithelial-mesenchymal transition; IRES: Internal ribosome entry site; lncRNA: Long non-coding RNA; miRNA: MicroRNA; MRE: MiRNA response element; ncRNA: Non-coding RNA; RBP: RNA-binding protein; RNA-seq: RNA sequencing; RT-PCR: Reverse transcription-polymerase chain reaction.

Synthesis and application of spermine-based amphiphilic poly(ß-amino ester)s for siRNA delivery.

Small interfering RNA (siRNA) can trigger RNA interference (RNAi) to therapeutically silence disease-related genes in human cells. The approval of siRNA therapeutics by the FDA in recent years generated a new hope in novel and efficient siRNA therapeutics. However, their therapeutic application is still limited by the lack of safe and efficient transfection vehicles. In this study, we successfully synthesized a novel amphiphilic poly(ß-amino ester) based on the polyamine spermine, hydrophobic decylamine and 1,4-butanediol diacrylate, which was characterized by 1H NMR spectroscopy and size exclusion chromatography (SEC, Mn = 6000 Da). The polymer encapsulated siRNA quantitatively from N/P 5 on as assessed by fluorescence intercalation while maintaining optimal polyplex sizes and zeta potentials. Biocompatibility and cellular delivery efficacy were also higher than those of the commonly used cationic, hyperbranched polymer polyethylenimine (PEI, 25 kDa). Optimized formulations mediated around 90% gene silencing in enhanced green fluorescence protein expressing H1299 cells (H1299-eGFP) as determined by flow cytometry. These results suggest that spermine-based, amphiphilic poly(ß-amino ester)s are very promising candidates for efficient siRNA delivery.