Iridium(III) carbene complexes as potent girdin inhibitors against metastatic cancers.

Many cancer-driving protein targets remain undruggable due to a lack of binding molecular scaffolds. In this regard, octahedral metal complexes with unique and versatile three-dimensional structures have rarely been explored as inhibitors of undruggable protein targets. Here, we describe antitumor iridium(III) pyridinium-N-heterocyclic carbene complex 1a, which profoundly reduces the viability of lung and breast cancer cells as well as cancer patient-derived organoids at low micromolar concentrations. Compound 1a effectively inhibits the growth of non-small-cell lung cancer and triple-negative breast cancer xenograft tumors, impedes the metastatic spread of breast cancer cells, and can be modified into an antibody-drug conjugate payload to achieve precise tumor delivery in mice. Identified by thermal proteome profiling, an important molecular target of 1a in cellulo is Girdin, a multifunctional adaptor protein that is overexpressed in cancer cells and unequivocally serves as a signaling hub for multiple pivotal oncogenic pathways. However, specific small-molecule inhibitors of Girdin have not yet been developed. Notably, 1a exhibits high binding affinity to Girdin with a Kd of 1.3 µM and targets the Girdin-linked EGFR/AKT/mTOR/STAT3 cancer-driving pathway, inhibiting cancer cell proliferation and metastatic activity. Our study reveals a potent Girdin-targeting anticancer compound and demonstrates that octahedral metal complexes constitute an untapped library of small-molecule inhibitors that can fit into the ligand-binding pockets of key oncoproteins.

Characterization of AST-001 non-clinical pharmacokinetics: A novel selective AKR1C3-activated prodrug in mice, rats, and cynomolgus monkeys.

AST-001 is a chemically synthesized inactive nitrogen mustard prodrug that is selectively cleaved to a cytotoxic aziridine (AST-2660) via aldo-keto reductase family 1 member C3 (AKR1C3). The purpose of this study was to investigate the pharmacokinetics and tissue distribution of the prodrug, AST-001, and its active metabolite, AST-2660, in mice, rats, and monkeys. After single and once daily intravenous bolus doses of 1.5, 4.5, and 13.5 mg/kg AST-001 to Sprague-Dawley rats and once daily 1 h intravenous infusions of 0.5, 1.5, and 4.5 mg/kg AST-001 to cynomolgus monkeys, AST-001 exhibited dose-dependent pharmacokinetics and reached peak plasma levels at the end of the infusion. No significant accumulation and gender differences were observed after 7 days of repeated dosing. In rats, the half-life of AST-001 was dose independent and ranged from 4.89 to 5.75 h. In cynomolgus monkeys, the half-life of AST-001 was from 1.66 to 5.56 h and increased with dose. In tissue distribution studies conducted in Sprague-Dawley rats and in liver cancer PDX models in female athymic nude mice implanted with LI6643 or LI6280 HepG2-GFP tumor fragments, AST-001 was extensively distributed to selected tissues. Following a single intravenous dose, AST-001 was not excreted primarily as the prodrug, AST-001 or the metabolite AST-2660 in the urine, feces, and bile. A comprehensive analysis of the preclinical data and inter-species allometric scaling were used to estimate the pharmacokinetic parameters of AST-001 in humans and led to the recommendation of a starting dose of 5 mg/m2 in the first-in-human dose escalation study.

The loss of B7-H4 expression in breast cancer cells escaping from T cell cytotoxicity contributes to epithelial-to-mesenchymal transition.

BACKGROUND: B7 homology 4 (B7-H4), a potential target for cancer therapy, has been demonstrated to inhibit T cell cytotoxicity in the early stages of breast cancer. However, B7-H4 manipulating breast tumor immune microenvironment (TIME) in the tumor progression remains unknown. METHODS: We engineered T cells with B7-H4-specific chimeric antigen receptors (CARs) and performed a T cell co-culture assay to characterize B7-H4 expression level in breast cancer cells escaping from T cell cytotoxicity. We generated B7-H4 knockout (KO) and overexpression (OE) breast cancer cells to determine the epithelial-to-mesenchymal transition (EMT) and stemness characteristics in vitro and in vivo, including tumor proliferation, migration, metastasis and chemoresistance. The Cancer Genome Atlas breast cancer database was accessed to investigate the correlation between B7-H4 expression levels and EMT characteristics in patients with breast cancer. RESULTS: Our result found that B7-H4 expression level was significantly reduced in a subset of breast cancer cells that escaped from the cytotoxicity of B7-H4 CAR-T cells. Compared with wild type cells, B7-H4 KO cells prompt EMT and stemness characteristics, including migration, invasion and metastasis, and OE cells vice versa. The increase in H3K27me3 in KO cells confirmed the epigenetic reprogramming of cancer stem cells. The IC50 of doxorubicin or oxaliplatin significantly increased in KO cells, which was in agreement with a decrease in OE cells. Moreover, a trend of downregulated B7-H4 from stage I to stage II breast cancer patients indicates that the low-expressing B7-H4 breast cancer cells escaping from TIME have spread to nearby breast lymph nodes in the cancer progression. CONCLUSIONS: Our study illuminates the novel role of renouncing B7-H4 in breast cancer cells through immune escape, which contributes to EMT processes and provides new insights for breast cancer treatments.

Dihydroartemisinin engages liver fatty acid binding protein and suppresses metastatic hepatocellular carcinoma growth.

Dihydroartemisinin non-covalently binds liver fatty acid binding protein (FABP1) with micromolar affinity, acts as a FABP1-dependent peroxisome proliferator-activated receptor alpha agonist and inhibits metastatic hepatocellular carcinoma growth.

DNA topoisomerase 2-associated proteins PATL1 and PATL2 regulate the biogenesis of hERG K+ channels.

The human ether-a-go-go-related gene (hERG) K+ channel conducts a rapidly activating delayed rectifier K+ current (IKr), which is essential for normal electrical activity of the heart. Precise regulation of hERG channel biogenesis is critical for serving its physiological functions, and deviations from the regulation result in human diseases. However, the mechanism underlying the precise regulation of hERG channel biogenesis remains elusive. Here, by using forward genetic screen, we found that PATR-1, the Caenorhabditis elegans homolog of the yeast DNA topoisomerase 2-associated protein PAT1, is a critical regulator for the biogenesis of UNC-103, the ERG K+ channel in C. elegans. A loss-of-function mutation in patr-1 down-regulates the expression level of UNC-103 proteins and suppresses the phenotypic defects resulted from a gain-of-function mutation in the unc-103 gene. Furthermore, downregulation of PATL1 and PATL2, the human homologs of PAT1, decreases protein levels and the current density of native hERG channels in SH-SY5Y cells and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Knockdown of PATL1 and PATL2 elongates the duration of action potentials in hiPSC-CMs, suggesting that PATL1 and PATL2 affect the function of hERG channels and hence electrophysiological characteristics in the human heart. Further studies found that PATL1 and PATL2 interact with TFIIE, a general transcription factor required for forming the RNA polymerase II preinitiation complex, and dual-luciferase reporter assays indicated that PATL1 and PATL2 facilitate the transcription of hERG mRNAs. Together, our study discovers that evolutionarily conserved DNA topoisomerase 2-associated proteins regulate the biogenesis of hERG channels via a transcriptional mechanism.

Overexpression of miR-3653 is Associated with HPV Infection and Serves as a Biomarker in Patients with Cervical Cancer.

Background: Human papillomavirus (HPV) is a major cause of cervical cancer (CC) occurrence. This study aimed to explore whether abnormal microRNA (miR)-3653 is associated with HPV infection and to investigate the clinical value of miR-3653 in the diagnosis and prognosis of CC. Methods: Tumor tissues and adjacent non-cancerous tissues were collected from 136 patients with CC. Cervical tissues from 101 patients with uterine fibroids were collected as controls. The expression of miR-3653 was measured by quantitative real-time PCR. The ability of miR-3653 to discriminate between HPV positive (HPV+) and HPV negative (HPV-) CC patients, and to discriminate patients from controls was assessed by receiver operating characteristic analysis. Kaplan-Meier curves and Log rank tests were used to evaluate the relationship of miR-3653 with survival of CC patient. Whether miR-3653 could function as a prognostic indicator was evaluated by univariate and multivariate Cox analyses. Results: miR-3653, highly expressed in CC tissues, was associated with HPV infection, tumor diameter, International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastasis in CC patients. Additionally, miR-3653 was increased in HPV+ controls, CC patients and CC cells. Moreover, miR-3653 could screen HPV+ controls, screen HPV+ patients and screen CC patients. Furthermore, miR-3653 was associated with the survival of CC patients (log-rank P < 0.001) and could serve as an independent prognostic indicator for CC patients. Conclusion: miR-3653, increased in CC, is related to HPV infection and may serve as a diagnostic and prognostic biomarker for CC patients.

Radiomics Based on DCE-MRI Improved Diagnostic Performance Compared to BI-RADS Analysis in Identifying Sclerosing Adenosis of the Breast.

Purpose: Sclerosing adenosis (SA) is a benign lesion that could mimic breast carcinoma and be evaluated as malignancy by Breast Imaging-Reporting and Data System (BI-RADS) analysis. We aimed to construct and validate the performance of radiomic model based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) compared to BI-RADS analysis to identify SA. Methods: Sixty-seven patients with invasive ductal carcinoma (IDC) and 58 patients with SA were included in this retrospective study from two institutions. The 125 patients were divided into a training cohort (n= 88) from institution I and a validation cohort from institution II (n=37). Dynamic contrast-enhanced sequences including one pre-contrast and five dynamic post-contrast series were obtained for all cases with different 3T scanners. Single-phase enhancement, multi-phase enhancement, and dynamic radiomic features were extracted from DCE-MRI. The least absolute shrinkage and selection operator (LASSO) logistic regression and cross-validation was performed to build the radscore of each single-phase enhancement and the final model combined multi-phase and dynamic radiomic features. The diagnostic performance of radiomics was evaluated by receiver operating characteristic (ROC) analysis and compared to the performance of BI-RADS analysis. The classification performance was tested using external validation. Results: In the training cohort, the AUCs of BI-RADS analysis were 0.71 (95%CI [0.60, 0.80]), 0.78 (95%CI [0.67, 0.86]), and 0.80 (95%CI [0.70, 0.88]), respectively. In single-phase analysis, the second enhanced phase radiomic signature achieved the highest AUC of 0.88 (95%CI [0.79, 0.94]) in distinguishing SA from IDC. Nine multi-phase radiomic features and two dynamic radiomic features showed the best predictive ability for final model building. The final model improved the AUC to 0.92 (95%CI [0.84, 0.97]), and showed statistically significant differences with BI-RADS analysis (p<0.05 for all). In the validation cohort, the AUC of the final model was 0.90 (95%CI [0.75, 0.97]), which was higher than all BI-RADS analyses and showed statistically significant differences with one of the BI-RADS analysis observers (p = 0.03). Conclusions: Radiomics based on DCE-MRI could show better diagnostic performance compared to BI-RADS analysis in differentiating SA from IDC, which may contribute to clinical diagnosis and treatment.

Pectin methyltransferase QUASIMODO2 functions in the formation of seed coat mucilage in Arabidopsis.

Pectin, cellulose, and hemicelluloses are major components of primary cell walls in plants. In addition to cell adhesion and expansion, pectin plays a central role in seed mucilage. Seed mucilage contains abundant pectic rhamnogalacturonan-I (RG-I) and lower amounts of homogalacturonan (HG), cellulose, and hemicelluloses. Previously, accumulated evidence has addressed the role of pectin RG-I in mucilage production and adherence. However, less is known about the function of pectin HG in seed coat mucilage formation. In this study, we analyzed a novel mutant, designated things fall apart2 (tfa2), which contains a mutation in HG methyltransferase QUASIMODO2 (QUA2). Etiolated tfa2 seedlings display short hypocotyls and adhesion defects similar to qua2 and tumorous shoot development2 (tsd2) alleles, and show seed mucilage defects. The diminished uronic acid content and methylesterification degree of HG in mutant seed mucilage indicate the role of HG in the formation of seed mucilage. Cellulosic rays in mutant mucilage are collapsed. The epidermal cells of seed coat in tfa2 and tsd2 display deformed columellae and reduced radial wall thickness. Under polyethylene glycol treatment, seeds from these three mutant alleles exhibit reduced germination rates. Together, these data emphasize the requirement of pectic HG biosynthesis for the synthesis of seed mucilage, and the functions of different pectin domains together with cellulose in regulating its formation, expansion, and release.

Dysregulated circulating miR-4429 serves as a novel non-invasive biomarker and is correlated with EGFR mutation in patients with non-small cell lung cancer.

This study aimed to investigate the correlation between microRNA (miR)-4429 and epidermal growth factor receptor (EGFR), the expression and clinical significance of miR-4429 in patients with non-small cell lung cancer (NSCLC), and the relationship between miR-4429 and EGFR mutation in NSCLC patients. Blood samples were collected from 122 NSCLC patients and 72 healthy volunteers. miR-4429 expression and EGFR mRNA expression were detected by real-time quantitative PCR. Correlation between miR-4429 and EGFR was evaluated by dual­luciferase reporter assay and the Pearson correlation analysis. The ability of serum miR­4429 to discriminate between NSCLC patients and healthy controls, and to discriminate between EGFR wild-type (EGFR-W) and EGFR mutant-type (EGFR-M) patients was assessed using receiver operating characteristic analysis. The relationship between miR-4429 and NSCLC patients' survival was identified by Kaplan-Meier survival curves and log-rank test. The prognostic value of miR-4429 in NSCLC patients was evaluated by Cox regression analysis. miR-4429 could directly bind to EGFR. Serum miR-4429, decreased in NSCLC patients, was negatively correlated with serum EGFR mRNA expression in NSCLC patients. Additionally, miR-4429 had a high diagnostic value for screening NSCLC patients from healthy controls, and was independently correlated with survival prognosis of NSCLC patients. Moreover, miR­4429 was decreased in EGFR-M patients, which had a certain screening ability for EGFR­M patients. Our findings indicate that miR-4429 is negatively correlated with EGFR in NSCLC, and may function as a diagnostic and prognostic biomarker for NSCLC patients. Additionally, miR-4429 is associated with EGFR mutation in NSCLC patients.

Progress on familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is an autosomal inherited disease characterized by a significant increase in low density lipoprotein cholesterol (LDL-C), tendon xanthoma and premature coronary artery disease (PCAD). In this paper, we analyze the current research status of FH, summarize the reported mutation gene loci in Chinese FH patients and treatment for them, and elaborate the current status of patents and drug researches. The results show that scientific outcomes of FH are increasing with a good developmental trend and the most popular topics of FH study are pathogenesis, treatment of FH, and research on juvenile FH patients. In terms of patents, large pharmaceutical companies, such as Regeneron Pharmaceuticals Inc, AstraZeneca Plc, Merck & Co Inc, are actively engaged in FH detection, diagnosis and treatment. In addition, 12 drugs have been launched in the United States, Japan, Europe and other countries or regions, bringing hope to FH patients.

Exosomal microRNA-588 from M2 polarized macrophages contributes to cisplatin resistance of gastric cancer cells.

BACKGROUND: Gastric cancer is a prevalent malignant cancer with a high incidence and significantly affects the health of modern people globally. Cisplatin (DDP) is one of the most common and effective chemotherapies for patients with gastric cancer, but DDP resistance remains a severe clinical challenge. AIM: To explore the function of M2 polarized macrophages-derived exosomal microRNA (miR)-588 in the modulation of DDP resistance of gastric cancer cells. METHODS: M2 polarized macrophages were isolated and identified by specific markers using flow cytometry analysis. The exosomes from M2 macrophages were identified by transmission electron microscopy and related markers. The uptake of the PKH67-labelled M2 macrophages-derived exosomes was detected in SGC7901 cells. The function and mechanism of exosomal miR-588 from M2 macrophages in the modulation of DDP resistance of gastric cancer cells was analyzed by CCK-8 assay, apoptosis analysis, colony formation assay, Western blot analysis, qPCR analysis, and luciferase reporter assay in SGC7901 and SGC7901/DDP cells, and by tumorigenicity analysis in nude mice. RESULTS: M2 polarized macrophages were isolated from mouse bone marrow stimulated with interleukin (IL)-13 and IL-4. Co-cultivation of gastric cancer cells with M2 polarized macrophages promoted DDP resistance. M2 polarized macrophages-derived exosomes could transfer in gastric cancer cells to enhance DDP resistance. Exosomal miR-588 from M2 macrophages contributed to DDP resistance of gastric cancer cells. miR-588 promoted DDP-resistant gastric cancer cell growth in vivo. miR-588 was able to target cylindromatosis (CYLD) in gastric cancer cells. The depletion of CYLD reversed miR-588 inhibition-regulated cell proliferation and apoptosis of gastric cancer cells exposed to DDP. CONCLUSION: In conclusion, we uncovered that exosomal miR-588 from M2 macrophages contributes to DDP resistance of gastric cancer cells by partly targeting CYLD. miR-588 may be applied as a potential therapeutic target for the treatment of gastric cancer.

LINC01420 Serves as a Novel Prognostic Biomarker and Promotes Cell Proliferation, Migration, and Invasion by Suppressing miR-149-5p in Gastric Cancer.

Gastric cancer (GCa) is the most common human health-threatening malignancy, and its high incidence and poor prognosis. Previous studies have shown that long non-coding RNAs (lncRNAs) are aberrantly expressed in a variety of tumors and are involved in tumor progression. This study aimed to investigate the regulatory role of LINC01420 in GCa cell proliferation migration and invasion, and search for new prognostic biomarkers for GCa. The expression levels of LINC01420 and miR-149-5p in GCa cells were analyzed with reverse transcription-quantitative PCR. Kaplan Meier survival analysis and Cox regression were used to analyze the prognostic value. Luciferase reporter assay was used to detect the interaction between LINC01420 and miR-149-5p. The effects of LINC01420/miR-149-5p axis on GCa cell proliferation, migration and invasion were assessed by CCK-8 and Transwell assays. LINC01420 expression levels were significantly increased in tissues and cell lines of GCa. Kaplan Meier curve results showed that overexpression of LINC01420 predicted poor prognosis. Silencing LINC01420 could inhibit the proliferation migration and invasion of GCa cells. The luciferase reporter assay results indicated that miR-149-5p might be a target of LINC01420 and mediate the effects of LINC01420 on GCa cell proliferation and migration and invasion. In conclusion, this study demonstrates an important regulatory role of the LINC01420/miR-149-5p axis in GCa progression and it provides a novel and significant biomarker for GCa treatment and prognosis.

Acute liver failure with thrombotic microangiopathy due to sodium valproate toxicity: A case report.

BACKGROUND: Sodium valproate is widely used in the treatment of epilepsy in clinical practice. Most adverse reactions to sodium valproate are mild and reversible, while serious idiosyncratic side effects are becoming apparent, particularly hepatotoxicity. Herein, we report a case of fatal acute liver failure (ALF) with thrombotic microangiopathy (TMA) caused by treatment with sodium valproate in a patient following surgery for meningioma. CASE SUMMARY: A 42-year-old man who received antiepileptic treatment with sodium valproate after surgery for meningioma exhibited extreme fatigue, severe jaundice accompanied by oliguria, soy sauce-colored urine, and ecchymosis. His postoperative laboratory values indicated a rapid decreased platelet count and hemoglobin level, severe liver and kidney dysfunction, and disturbance of the coagulation system. He was diagnosed with drug-induced liver failure combined with TMA. After plasma exchange combined with hemoperfusion, pulse therapy with high-dose methylprednisolone, and blood transfusion, his liver function deteriorated, and finally, he died. CONCLUSION: ALF with TMA is a rare and fatal adverse reaction of sodium valproate which needs to be highly valued.

The value of percentile base on computed tomography histogram in differentiating the invasiveness of adenocarcinoma appearing as pure ground-glass nodules.

To investigate the value of percentile base on computed tomography (CT) histogram analysis for distinguishing invasive adenocarcinoma (IA) from adenocarcinoma in situ (AIS) or micro invasive adenocarcinoma (MIA) appearing as pure ground-glass nodules.A total of 42 cases of pure ground-glass nodules that were surgically resected and pathologically confirmed as lung adenocarcinoma between January 2015 and May 2019 were included. Cases were divided into IA and AIS/MIA in the study. The percentile on CT histogram was compared between the 2 groups. Univariate and multivariate logistic regression were used to determine which factors demonstrated a significant effect on invasiveness. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) was used to evaluate the predictive ability of individual characteristics and the combined model.The 4 histogram parameters (25th percentile, 55th percentile, 95th percentile, 97.5th percentile) and the combined model all showed a certain diagnostic value. The combined model demonstrated the best diagnostic performance. The AUC values were as follows: 25th percentile = 0.693, 55th percentile = 0.706, 95th percentile = 0.713, 97.5th percentile = 0.710, and combined model = 0.837 (all P < .05).The percentile of histogram parameters help to improve the ability to radiologically determine the invasiveness of lung adenocarcinoma appearing as pure ground-glass nodules.

A Nomogram Combined Radiomic and Semantic Features as Imaging Biomarker for Classification of Ovarian Cystadenomas.

Objective: To construct and validate a combined Nomogram model based on radiomic and semantic features to preoperatively classify serous and mucinous pathological types in patients with ovarian cystadenoma. Methods: A total of 103 patients with pathology-confirmed ovarian cystadenoma who underwent CT examination were collected from two institutions. All cases divided into training cohort (N = 73) and external validation cohort (N = 30). The CT semantic features were identified by two abdominal radiologists. The preprocessed initial CT images were used for CT radiomic features extraction. The LASSO regression were applied to identify optimal radiomic features and construct the Radscore. A Nomogram model was constructed combining the Radscore and the optimal semantic feature. The model performance was evaluated by ROC analysis, calibration curve and decision curve analysis (DCA). Result: Five optimal features were ultimately selected and contributed to the Radscore construction. Unilocular/multilocular identification was significant difference from semantic features. The Nomogram model showed a better performance in both training cohort (AUC = 0.94, 95%CI 0.86-0.98) and external validation cohort (AUC = 0.92, 95%CI 0.76-0.98). The calibration curve and DCA analysis indicated a better accuracy of the Nomogram model for classification than either Radscore or the loculus alone. Conclusion: The Nomogram model combined radiomic and semantic features could be used as imaging biomarker for classification of serous and mucinous types of ovarian cystadenomas.

B7H4 expression in tumor cells impairs CD8 T cell responses and tumor immunity.

B7 homolog 4 (B7H4) is considered a negative regulator of immune responses, but the immunoregulatory role of B7H4 in the tumor microenvironment is not clear. Here, we assessed B7H4 expression cell types in human breast cancer tissues and addressed its potential mechanisms in the CD8 T cell immune response. The results from flow cytometry and immunohistochemistry demonstrated that B7H4 was highly expressed in 26 out of 30 (86.7%) breast invasive ductal carcinomas, and B7H4 surface expression on tumor cells was inversely correlated with CD8 T lymphocytes infiltration (p < 0.0001). In vivo, B7H4-overexpressing tumor cells showed enhanced tumor growth in immunocompetent mice with impaired CD8 T cell infiltration of the tumor. Further investigation showed that activation and expansion of CD8 T cells within the lymph nodes were suppressed in B7H4-overexpessing tumor-bearing mice. An in vitro killing assay showed that the cytotoxicity of CD8 T cells was inhibited in B7H4-overexpressing tumor cells. These findings suggest that B7H4 in tumor cells is a negative regulator of CD8 T cell activation, expansion and cytotoxicity, indicating that tumor cell-associated B7H4 might be a target for T cell-based cancer immunotherapy.

MiR-7-5p-mediated downregulation of PARP1 impacts DNA homologous recombination repair and resistance to doxorubicin in small cell lung cancer.

BACKGROUND: Chemo-resistance is one of the major challenges in the therapy of small cell lung cancer (SCLC). Multiple mechanisms are thought to be involved in chemo-resistance during SCLC treatment, but unfortunately, these mechanisms have not been well elucidated. Herein, we investigated the role of miRNA in the resistance of SCLC cells to doxorubicin (Dox). METHODS: MiRNA microarray analysis revealed that several miRNAs, including miR-7-5p, were specifically decreased in Dox-resistant SCLC cells (H69AR) compared to parental cells (H69). The expression level of miR-7-5p was confirmed by qRT-PCR in Dox-resistant cells (H69AR and H446AR cells) and their parental cells. Bioinformatic analysis indicated that poly ADP-ribose polymerase 1 (PARP1) is a direct target of miR-7-5p. The binding sites of miR-7-5p in the PARP1 3' UTR were verified by luciferase reporter and Western blot assays. To investigate the role of miR-7-5p in the chemo-resistance of SCLC cells to doxorubicin, mimic or inhibitor of miR-7-5p was transfected into SCLC cells, and the effect of miR-7-5p on homologous recombination (HR) repair was analyzed by HR reporter assays. Furthermore, the expression of HR repair factors (Rad51 and BRCA1) induced by doxorubicin was detected by Western blot and immunofluorescent staining in H446AR cells transfected with miR-7-5p mimic. RESULTS: The expression level of miR-7-5p was remarkably reduced (4-fold) in Dox-resistant SCLC cells (H69AR and H446AR cells) compared with that in parental cells (H69 and H446 cells). Poly ADP-ribose polymerase 1 (PARP1) is a direct target of miR-7-5p, and PARP1 expression was downregulated by miR-7-5p. MiR-7-5p impeded Dox-induced HR repair by inhibiting the expression of HR repair factors (Rad51 and BRCA1) that resulted in resensitizing SCLC cells to doxorubicin. CONCLUSIONS: Our findings provide evidence that miR-7-5p targets PARP1 to exert its suppressive effects on HR repair, indicating that the alteration of the expression of miR-7-5p may be a promising strategy for overcoming chemo-resistance in SCLC therapy.

Local Irradiation Sensitized Tumors to Adoptive T Cell Therapy via Enhancing the Cross-Priming, Homing, and Cytotoxicity of Antigen-Specific CD8 T Cells.

The successful generation of T cell-mediated immunity for the treatment of cancer has been a major focal point of research. One of the critical strategies of cancer immunotherapy is to efficiently activate antigen-specific CD8 T cells in the immunosuppressive tumor environment. Here, we used transgenic OT-I/CD45.2/Rag-/- mice as a source of effector CD8 T cells to determine whether irradiation combined with adoptive T cell transfer therapy could improve T cell proliferation and effector function in murine tumor models. Local irradiation combined with adoptive T cell therapy showed a synergistic effect on tumor growth inhibition in mice. Mechanistically, irradiation increased the release of tumor-associated antigens, which facilitated cross-presentation of tumor-associated antigens by dendritic cells and the priming of antigen-specific T lymphocytes. Additionally, irradiation enhanced the homing of the antigen-specific T cells to tumor tissues via the increased release of CCL5, CXCL9, and CXCL11 from tumor cells. Moreover, irradiation enhanced the proliferation and effector function of both adoptively transferred T cells and endogenous antigen-specific T cells. Our findings provide evidence to support that local irradiation enhanced the therapeutic efficacy of adoptive T cell therapy for cancer, indicating that the combination of radiotherapy and adoptive T cell therapy may be a promising strategy for tumor treatment.

Tetrameric Assembly of K+ Channels Requires ER-Located Chaperone Proteins.

Tetrameric assembly of channel subunits in the endoplasmic reticulum (ER) is essential for surface expression and function of K+ channels, but the molecular mechanism underlying this process remains unclear. In this study, we found through genetic screening that ER-located J-domain-containing chaperone proteins (J-proteins) are critical for the biogenesis and physiological function of ether-a-go-go-related gene (ERG) K+ channels in both Caenorhabditis elegans and human cells. Human J-proteins DNAJB12 and DNAJB14 promoted tetrameric assembly of ERG (and Kv4.2) K+ channel subunits through a heat shock protein (HSP) 70-independent mechanism, whereas a mutated DNAJB12 that did not undergo oligomerization itself failed to assemble ERG channel subunits into tetramers in vitro and in C. elegans. Overexpressing DNAJB14 significantly rescued the defective function of human ether-a-go-go-related gene (hERG) mutant channels associated with long QT syndrome (LQTS), a condition that predisposes to life-threatening arrhythmia, by stabilizing the mutated proteins. Thus, chaperone proteins are required for subunit stability and assembly of K+ channels.

Therapeutic effect comparison of hepatocyte-like cells and bone marrow mesenchymal stem cells in acute liver failure of rats.

GOALS: To evaluate the therapeutic efficacy of rat bone marrow mesenchymal stem cells (BMSCs) induced into hepatocyte-like cells and of un-induced BMSCs in acute liver failure rats. METHODS: BMSCs in highly homogenous passage 3 were cultured using the whole bone marrow adherent culture method. Hepatic-related characters were confirmed with morphology, RT-PCR analysis, glycogen staining and albumin (ALB) immunofluorescence assay. Carbon tetrachloride (CCl4) was injected intraperitoneally to establish an acute rat liver failure model. Hepatocyte-like cells or un-induced BMSCs were respectively injected into the models to examine rats' appearance, liver function assay and liver tissue pathology. RESULTS: Hepatocyte-like morphology, higher expression of cytokeratin 18 (CK18) mRNA and ALB protein, and glycogen accumulation were confirmed in the induced BMSCs. The transplanted DAPI-labeled BMSCs were localized in the liver tissue 3-14 days after transplantation. The levels of liver function indicators (AST, ALT, ALP, and TBIL) from transplanted rats were significant decreased and pathology was improved, indicating the recovery of liver function. However, the differences were statistically insignificant. CONCLUSION: Both hepatocyte-like cells and un-induced BMSCs had a similarly positively therapeutic efficacy on liver regeneration in rat liver failure model.