A nomogram-based prediction model for dysphagia in patients with chronic obstructive pulmonary disease: A cross-sectional study.

AIM AND OBJECTIVES: To investigate the prevalence of dysphagia in patients with COPD, identify the risk factors for dysphagia, develop a visual clinical prediction model and quantitatively predict the probability of developing dysphagia. BACKGROUND: Patients with COPD are at high risk of dysphagia, which is strongly linked to the acute exacerbation of their condition. The use of effective tools to predict its risk may contribute to the early identification and treatment of dysphagia in patients with COPD. DESIGN: A cross-sectional design. METHODS: From July 2021 to April 2023, we enrolled 405 patients with COPD for this study. The clinical prediction model was constructed according to the results of a univariate analysis and a logistic regression analysis, evaluated by discrimination, calibration and decision curve analysis and visualized by a nomogram. This study was reported using the TRIPOD checklist. RESULTS: In total, 405 patients with COPD experienced dysphagia with a prevalence of 59.01%. A visual prediction model was constructed based on age, whether combined with cerebrovascular disease, chronic pulmonary heart disease, acute exacerbation of COPD, home noninvasive positive pressure ventilation, dyspnoea level and xerostomia level. The model exhibited excellent discrimination at an AUC of .879. Calibration curve analysis indicated a good agreement between experimental and predicted values, and the decision curve analysis showed a high clinical utility. CONCLUSION: The model we devised may be used in clinical settings to predict the occurrence of dysphagia in patients with COPD at an early stage. RELEVANCE TO CLINICAL PRACTICE: The model can help nursing staff to calculate the risk probability of dysphagia in patients with COPD, formulate personalized preventive care measures for high-risk groups as soon as possible to achieve early prevention or delay of dysphagia and its related complications and improve the prognosis. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Targeting ATP Synthase by Bedaquiline as a Therapeutic Strategy to Sensitize Ovarian Cancer to Cisplatin.

Cisplatin is a common chemotherapeutic drug for treating ovarian cancer, but its clinical efficacy is hampered by intrinsic and acquired resistance. Previous studies had shown inhibiting oxidative phosphorylation overcomes cisplatin resistance in ovarian cancer. Studies reveal that bedaquiline, a clinically available antimicrobial drug, inhibits cancer via targeting mitochondria. This study systematically assessed the efficacy of bedaquiline in ovarian cancer and its underlying mechanism. Using a panel of ovarian cancer cell lines and normal ovary cells, we demonstrated bedaquiline is selective for anti-ovarian cancer activities. Furthermore, the sensitivity varied among different ovarian cancer cell lines regardless of their sensitivity to cisplatin. Bedaquiline inhibited growth, survival and migration, through decreasing levels of ATP synthase subunit, complex V activity, mitochondrial respiration and ATP. We further found that ovarian cancer displayed increased levels of ATP, oxygen consumption rate (OCR), complex V activity and ATP synthase subunits compared to normal counterpart. Combination index analysis showed that bedaquiline and cisplatin is synergistic. Bedaquiline remarkably enhanced the efficacy of cisplatin in inhibiting ovarian cancer growth in mice. Our study provides evidence to repurpose bedaquiline for ovarian cancer treatment and suggests that ATP synthase is a selective target to overcome cisplatin resistance in ovarian cancer.

Genetically Encoded and Biologically Produced All-DNA Nanomedicine Based on One-Pot Assembly of DNA Dendrimers for Targeted Gene Regulation.

All-DNA nanomedicines have emerged as potential anti-tumor drugs. DNA nanotechnology provides all-DNA nanomedicines with unlimited possibilities in controlling the diversification of size, shape, and loads of the therapeutic motifs. As DNA is a biological polymer, it is possible to genetically encode and produce the all-DNA nanomedicines in living bacteria. Herein, DNA-dendrimer-based nanomedicines are designed to adapt to the biological production, which is constructed by the flexible 3-arm building blocks to enable a highly efficient one-pot DNA assembly. For the first time, a DNA nanomedicine, D4-3-As-DzSur, is successfully genetically encoded, biotechnologically produced, and directly self-assembled. The performance of the biologically produced D4-3-As-DzSur in targeted gene regulation has been confirmed by in vitro and in vivo studies. The biological production capability will fulfill the low-cost and large-scale production of all-DNA nanomedicines and promote clinical applications.

Paclitaxel induces autophagy in gastric cancer BGC823 cells.

This paper explores the connection between paclitaxel, a chemotherapeutic agent, and gastric cancer cells. In this experiment, it is demonstrated that paclitaxel triggers autophagy and inhibits proliferation of gastric cancer cells. An 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to detect cell viability and the IC50 of paclitaxel. Western blot was used to detect the expression levels of P62, and to measure the protein expression of autophagy. Immunofluorescence was used to reveal the appearance of punctate structures in the cytoplasm-this ultrastructure associated with autophagy was observed by microscopy. Electron microscopy revealed the formation of double-membrane autophagosomes, a typical structure of autophagy. In conclusion, our research indicates that paclitaxel may influence gastric cancer BGC823 cells by way of inducing autophagy.

Therapeutic effect of gefitinib in advanced non-small cell lung cancer and its effect on the EGFR level in peripheral blood.

PURPOSE: This study was designed to investigate the therapeutic effect of gefitinib in advanced non-small cell lung cancer (NSCLC) and its effect on the level of epidermal growth factor receptor (EGFR) in peripheral blood. METHODS: A total of 58 patients with NSCLC were treated with gefinitib (iressa) (250 mg per day). EGFR levels in the peripheral blood were measured with ELISA assay before and after treatment. Statistical analyses of patient quality of life, survival and other clinical data were conducted including logistic regression analysis, x2 test and t-test. Quality of life assessment was quantified based on the Chinese version of the QLQ-C30 and QLQ-LC13 questionnaires of the European Organization for Research and Treatment of Cancer. RESULTS: The overall response rate to iressa was 38% (22 patients), and the disease control rate (response+stable) was 74% (43 patients). The mean scores of assessment of physiological functions and comprehensive quality of life in QLQ-C30 questionnaire were significantly increased with an improvement rate of 91-100%. Similarly, the mean scores of assessment of disease symptoms in QLQ-LC12 questionnaire were significantly reduced with an overall improvement rate of 73-100). Adverse drug effects were mainly grade I and II skin rashes and diarrhea. The EGFR levels in peripheral blood were significantly decreased after treatment (p<0.05). CONCLUSION: Based on our results, gefitinib showed meaningful effects in treating advanced NSCLC, significantly improving clinical symptoms and ameliorating the patient quality of life.

Sodium butyrate-induced apoptosis and ultrastructural changes in MCF-7 breast cancer cells.

This study investigated the effects of sodium butyrate (NaB) on Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and analyzed the relevant mechanism. Here, we demonstrated that a certain concentration of NaB effectively induced MCF-7 cell apoptosis. Cell counting kit-8 (CCK-8) assay was used to detect cell viability and the apoptosis rate. Western blotting was used to detect changes in the Bcl-2 expression level. We observed cell shape changes with microscopy. Immunofluorescence revealed some apoptotic nuclei. Electron microscopy revealed thick nucleoli, chromatin margination, reduced mitochondria, and dramatic vacuoles. Collectively, our findings elucidated the morphological mechanism by which NaB changed the ultrastructure of MCF-7 cells.

Ritonavir binds to and downregulates estrogen receptors: molecular mechanism of promoting early atherosclerosis.

Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERß expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17ß-estradiol (E2), suggesting RTV acts as an antagonist for E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17ß-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis.

The Ultrastructure of MCF-7 Breast Cancer Cells after Vasodilator-Stimulated Phosphoprotein Knockdown.

Inhibition of vasodilator-stimulated phosphoprotein (VASP) expression could modulate the adhesion and proliferation of breast cancer cells. However, the underlying mechanisms are not well defined. Here, we show that knockdown of the VASP changes the ultrastructure of human MCF-7 breast cancer cells. Transfection of VASP shRNA significantly lowered the expression of VASP protein in MCF-7 cells. In the shRNA-VASP group, immunofluorescence showed diminished presence of F-actin, and it was lower in the nucleus than in the cytoplasm. After VASP was inhibited, the MCF-7 cells were oval in shape with blunt lamellipodium, disappearance of the cristae of mitochondria, decreased microvilli and more vacuoles. Collectively, our findings elucidated the morphological mechanism that knockdown of the VASP changed the ultrastructure of MCF-7 cells.

The protective effect of curcumin on hepatotoxicity and ultrastructural damage induced by cisplatin.

We investigate the protective effect of curcumin (CU) on the hepatic ultrastructural damage induced by cisplatin in mice. 18 adult Kunming mice were randomly divided into normal saline (NS) group, cisplatin treatment group (CP) and CU + CP group (n = 6 for each group). Mice in control group and CP group were administered with NS (20 mL/kg/day) and CU + CP group were i.p injected with CU (200 mg/kg/day) for 10 days. Then cisplatin (50 mg/kg/day) was injected in mice of CP group and CU + CP group, while those in control group were given the same volume of NS. Five days after injection all mice were killed and liver dissected. The hepatic morphological structures were observed under light microscope and transmission electron microscope. The results indicated that CU alleviated the hepatic histopathological damages induced by cisplatin, which included declined body weight, vacuolated cytoplasm and blurred liver trabecular structure. Moreover, no hepatic ultrastructural damages were observed in the CU protective group with condensed and marginated nuclear chromatin, bile canaliculi outstreched and bile deposited.

Ritonavir-induced hepatotoxicity and ultrastructural changes of hepatocytes.

To investigate the effect of ritonavir on hepatocyte proliferation, we detected the change of cleaved caspase-3 expression level in the hepatocytes. Furthermore, the morphological and ultrastructural changes of hepatocytes derived from RTV-treated mice have been observed. The results showed that ritonavir can evidently inhibit hepatocyte proliferation and increase cleaved caspase-3 expression level. Under the electron microscope, chromatin margination, mitochondrial cristae disappearance, karyopyknosis and cytoplasmic vacuolization can be observed in the hepatocytes of mice treated with ritonavir. In conclusion, the mechanism of ritonavir's hepatotoxicity is that it induces apoptosis of hepatocytes via the caspase-cascade system.

Macrophage migration inhibitor factor (MIF): Potential role in cognitive impairment disorders.

Macrophage migration inhibitory factor (MIF) is a cytokine in the immune system, participated in both innate and adaptive immune responses. Except from immune cells, MIF is also secreted by a variety of non-immune cells, including hematopoietic cells, endothelial cells (ECs), and neurons. MIF plays a crucial role in various diseases, such as sepsis, rheumatoid arthritis, acute kidney injury, and neurodegenerative diseases. The role of MIF in the neuropathogenesis of cognitive impairment disorders is emphasized, as it recruits multiple inflammatory mediators, leading to activating microglia or astrocyte-derived neuroinflammation. Furthermore, it contributes to the cell death of neurons and ECs with the binding of apoptosis-inducing factor (AIF) through parthanatos-associated apoptosis-inducing factor nuclease (PAAN) / MIF pathway. This review comprehensively delves into the relationship between MIF and the neuropathogenesis of cognitive impairment disorders, providing a series of emerging MIF-targeted pharmaceuticals as potential treatments for cognitive impairment disorders.

GPNMB Expression Associates with Inferior Prognosis in Patients with Small Cell Lung Cancer.

Purpose: Small cell lung cancer (SCLC) is widely recognized for its propensity for early and frequent metastases, which contribute to its status as a refractory malignancy. While the high expression of GPNMB in SCLC is well-documented, the precise correlation between GPNMB expression and the prognosis of SCLC remains undetermined. Methods: HTG Edge-seq was used to screen the differential gene expression between primary SCLC lesions and paired metastatic lymph nodes (LN). The plasma concentration of GPNMB was measured using enzyme-linked immunosorbent assay (ELISA). The relationship between GPNMB concentration and clinical characteristics, as well as overall survival (OS) was assessed. One-to-one propensity score matching (PSM) was performed to reduce bias from confounding factors between groups. The invasive, migratory, proliferative, and apoptotic abilities of SCLC cells were evaluated using migration and matrigel invasion assays, CCK8 assay and flow cytometry respectively. Results: GPNMB exhibited a significant up-regulation in LN compared to primary SCLC lesions as determined by HTG Edge-seq. Furthermore, patients with extensive disease demonstrated a significantly elevated plasma GPNMB concentration compared to those with local disease (P = 0.043). Additionally, patients with a high baseline plasma GPNMB level exhibited a shorter OS (10.32 vs. 16.10 months, P = 0.0299). Following PSM analysis, the statistical significance of the difference between the two groups persisted (9.43 vs. 15.27 months, P = 0.0146). Notably, both univariate and multivariate analyses confirmed that higher expression of GPNMB served as an independent biomarker for OS before PSM (P = 0.033, HR = 2.304) and after PSM (P = 0.003, HR = 6.190). Additionally, our study revealed that the inhibition of GPNMB expression through the use of siRNA effectively diminished the metastatic and proliferative capabilities of SCLC. Furthermore, this inhibition resulted in an enhanced ability to induce apoptosis. Conclusions: In light of our findings, it can be inferred that the expression of GPNMB is linked to metastasis and an unfavorable prognosis, thus suggesting its potential as a novel therapeutic target in the treatment of SCLC.

CAR-NK cells in combination therapy against cancer: A potential paradigm.

Various preclinical and a limited number of clinical studies of CAR-NK cells have shown promising results: efficient elimination of target cells without side effects similar to CAR-T therapy. However, the homing and infiltration abilities of CAR-NK cells are poor due to the inhibitory tumor microenvironment. From the perspective of clinical treatment strategies, combined with the biological and tumor microenvironment characteristics of NK cells, CAR-NK combination therapy strategies with anti-PD-1/PD-L1, radiotherapy and chemotherapy, kinase inhibitors, proteasome inhibitors, STING agonist, oncolytic virus, photothermal therapy, can greatly promote the proliferation, migration and cytotoxicity of the NK cells. In this review, we will summarize the targets selection, structure constructions and combinational therapies of CAR-NK cells for tumors to provide feasible combination strategies for overcoming the inhibitory tumor microenvironment and improving the efficacy of CAR-NK cells.

Botulinum toxin A attenuates osteoarthritis development via inhibiting chondrocyte ferroptosis through SLC7Al1/GPX4 axis.

Osteoarthritis (OA) is a prevalent joint degenerative disease, resulting in a significant societal burden. However, there is currently a lack of effective treatment option available. Previous studies have suggested that Botulinum toxin A (BONT/A), a macromolecular protein extracted from Clostridium Botulinum, may improve the pain and joint function in OA patients, but the mechanism remains elusive. This study was to investigate the impact and potential mechanism of BONT/A on OA in vivo and in vitro experiment. LPS increased the levels of ROS, Fe2+and Fe3+, as well as decreased GSH levels, the ratio of GSH / GSSH and mitochondrial membrane potential. It also enhanced the degeneration of extracellular matrix (ECM) and altered the ferroptosis-related protein expression in chondrocytes. BONT/A rescued LPS-induced decrease in collagen type II (Collagen II) expression and increase in matrix metalloproteinase 13 (MMP13), mitigated LPS-induced cytotoxicity in chondrocytes, abolished the accumulation of ROS and iron, upregulated GSH and the ratio of GSH/ GSSH, improved mitochondrial function, and promoted SLC7A11/GPX4 anti-ferroptosis system activation. Additionally, intra-articular injection of BONT/A inhibited the degradation of cartilage in OA model rats. This chondroprotective effect of BONT/A was reversed by erastin (a classical ferroptosis agonist) and enhanced by liproxstatin-1 (a classic ferroptosis inhibitor). Our research confirms that BONT/A alleviates the OA development by inhibiting the ferroptosis of chondrocytes, which revealed to be a potential therapeutic mechanism for BONT/A treating the OA.

Matrine inhibits the adhesion and migration of BCG823 gastric cancer cells by affecting the structure and function of the vasodilator-stimulated phosphoprotein (VASP).

AIM: Vasodilator-stimulated phosphoprotein (VASP) expression is upregulated in human cancers and correlates with more invasive advanced tumor stages. The aim of this study was to elucidate the mechanisms by which matrine, an alkaloid derived from Sophora species plants, acted on the VASP protein in human gastric cancer cells in vitro. METHODS: VASP was expressed and purified. Intrinsic fluorescence spectroscopy was used to study the binding of matrine to VASP. CD spectroscopy was used to examine the changes in the VASP protein secondary structure. Human gastric carcinoma cell line BGC823 was tested. Scratch wound and cell adhesion assays were used to detect the cell migration and adhesion, respectively. Real-time PCR and Western blotting assays were used to measure mRNA and protein expression of VASP. RESULTS: In the fluorescence assay, the dissociation constant for binding of matrine to VASP protein was 0.86 mmol/L, thus the direct binding between the two molecules was weak. However, matrine (50 µg/mL) caused obvious change in the secondary structure of VASP protein shown in CD spectrum. Treatments of BGC823 cells with matrine (50 µg/mL) significantly inhibited the cell migration and adhesion. The alkaloid changed the subcellular distribution of VASP and formation of actin stress fibers in BGC823 cells. The alkaloid caused small but statistically significant decreases in VASP protein expression and phosphorylation, but had no significant effect on VASP mRNA expression. CONCLUSION: Matrine modulates the structure, subcellular distribution, expression and phosphorylation of VASP in human gastric cancer cells, thus inhibiting the cancer cell adhesion and migration.

Echinocystic acid alleviated hypoxic-ischemic brain damage in neonatal mice by activating the PI3K/Akt/Nrf2 signaling pathway.

Neonatal hypoxic-ischemic encephalopathy (HIE) is considered a major cause of death and long-term neurological injury in newborns. Studies have demonstrated that oxidative stress and apoptosis play a major role in the progression of neonatal HIE. Echinocystic acid (EA), a natural plant extract, shows great antioxidant and antiapoptotic activities in various diseases. However, it has not yet been reported whether EA exerts a neuroprotective effect against neonatal HIE. Therefore, this study was undertaken to explore the neuroprotective effects and potential mechanisms of EA in neonatal HIE using in vivo and in vitro experiments. In the in vivo study, a hypoxic-ischemic brain damage (HIBD) model was established in neonatal mice, and EA was administered immediately after HIBD. Cerebral infarction, brain atrophy and long-term neurobehavioral deficits were measured. Hematoxylin and eosin (H&E), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and dihydroethidium (DHE) staining were performed, and the contents of malondialdehyde (MDA) and glutathione (GSH) were detected. In the in vitro study, an oxygen-glucose deprivation/reperfusion (OGD/R) model was employed in primary cortical neurons, and EA was introduced during OGD/R. Cell death and cellular ROS levels were determined. To illustrate the mechanism, the PI3K inhibitor LY294002 and Nrf2 inhibitor ML385 were used. The protein expression levels of p-PI3K, PI3K, p-Akt, Akt, Nrf2, NQO1, and HO-1 were measured by western blotting. The results showed that EA treatment significantly reduced cerebral infarction, attenuated neuronal injury, and improved brain atrophy and long-term neurobehavioral deficits in neonatal mice subjected to HIBD. Meanwhile, EA effectively increased the survival rate in neurons exposed to OGD/R and inhibited oxidative stress and apoptosis in both in vivo and in vitro studies. Moreover, EA activated the PI3K/Akt/Nrf2 pathway in neonatal mice following HIBD and in neurons after OGD/R. In conclusion, these results suggested that EA alleviated HIBD by ameliorating oxidative stress and apoptosis via activation of the PI3K/Akt/Nrf2 signaling pathway.

UHRF1 inhibition epigenetically reprograms cancer stem cells to suppress the tumorigenic phenotype of hepatocellular carcinoma.

Cancer stem cells (CSCs) contribute to tumor initiation, progression, and recurrence in many types of cancer, including hepatocellular carcinoma (HCC). Epigenetic reprogramming of CSCs has emerged as a promising strategy for inducing the transition from malignancy to benignity. Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) is required for DNA methylation inheritance. Here, we investigated the role and mechanism of UHRF1 in regulating CSC properties and evaluated the impact of UHRF1 targeting on HCC. Hepatocyte-specific Uhrf1 knockout (Uhrf1HKO) strongly suppressed tumor initiation and CSC self-renewal in both diethylnitrosamine (DEN)/CCl4-induced and Myc-transgenic HCC mouse models. Ablation of UHRF1 in human HCC cell lines yielded consistent phenotypes. Integrated RNA-seq and whole genome bisulfite sequencing revealed widespread hypomethylation induced by UHRF1 silencing epigenetically reprogrammed cancer cells toward differentiation and tumor suppression. Mechanistically, UHRF1 deficiency upregulated CEBPA and subsequently inhibited GLI1 and Hedgehog signaling. Administration of hinokitiol, a potential UHRF1 inhibitor, significantly reduced tumor growth and CSC phenotypes in mice with Myc-driven HCC. Of pathophysiological significance, the expression levels of UHRF1, GLI1, and key axis proteins consistently increased in the livers of mice and patients with HCC. These findings highlight the regulatory mechanism of UHRF1 in liver CSCs and have important implications for the development of therapeutic strategies for HCC.

USP39 promotes hepatocellular carcinogenesis through regulating alternative splicing in cooperation with SRSF6/HNRNPC.

Abnormal alternative splicing (AS) caused by alterations in spliceosomal factors is implicated in cancers. Standard models posit that splice site selection is mainly determined by early spliceosomal U1 and U2 snRNPs. Whether and how other mid/late-acting spliceosome components such as USP39 modulate tumorigenic splice site choice remains largely elusive. We observed that hepatocyte-specific overexpression of USP39 promoted hepatocarcinogenesis and potently regulated splice site selection in transgenic mice. In human liver cancer cells, USP39 promoted tumor proliferation in a spliceosome-dependent manner. USP39 depletion deregulated hundreds of AS events, including the oncogenic splice-switching of KANK2. Mechanistically, we developed a novel RBP-motif enrichment analysis and found that USP39 modulated exon inclusion/exclusion by interacting with SRSF6/HNRNPC in both humans and mice. Our data represented a paradigm for the control of splice site selection by mid/late-acting spliceosome proteins and their interacting RBPs. USP39 and possibly other mid/late-acting spliceosome proteins may represent potential prognostic biomarkers and targets for cancer therapy.

Treatment of Pediatric Inflammatory Myofibroblastic Tumor: The Experience from China Children's Medical Center.

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal tumor with intermediate malignancy that tends to affect children primarily. To date, no standardized therapies exist for the treatment of IMT. This study aimed to share experience from China Children's Medical Center for the explorative treatment of IMT. METHODS: Patients with newly diagnosed IMT between January 2013 and December 2018 were included. Patients were grouped according to surgical margins and Intergroup Rhabdomyosarcoma Study Group (IRSG) staging. The clinical characteristic, therapeutic schedules, treatment response and clinical outcome were described. RESULTS: Six patients were enrolled in this study, including two boys and four girls, with a median age of 57 months (range 10-148 months). Among them, five patients were anaplastic lymphoma kinase positive. Four patients achieved complete remission and two patients attained partial remission after treatment with this protocol. All patients were alive after a median follow-up of 4 years (range 3-7 years). The most common treatment-related adverse reaction was myelosuppression. CONCLUSION: In this study, we demonstrated that IMT has a good prognosis and the treatment selected according to risk stratification was effective and feasible.

Elevated expression of RIT1 hyperactivates RAS/MAPK signal and sensitizes hepatocellular carcinoma to combined treatment with sorafenib and AKT inhibitor.

Hyperactivation of RAS/MAPK signaling is commonly observed in hepatocellular carcinoma (HCC). Gain-of-function mutations of canonical RAS genes, however, are rarely detected and it remains unclear how the activity of this pathway is turned on during hepatocarcinogenesis. We performed a comprehensive analysis of RAS superfamily genetic alterations across ten subfamilies, 152 members in 377 HCC patients from the Cancer Genome Atlas database. RIT1 (Ras-like without CAAX 1) was the most frequently altered RAS member amplified in 13% of the HCC cohort. Both genomic amplification and CREB-mediated transcriptional activation contributed to the elevated RIT1 expression, and its overexpression correlated with RAS/MAPK activation and poor prognosis. Then, we found that RIT1-induced angiogenesis via the MEK/ERK/EIF4E/HIF1-α/VEGFA axis. MAP3K11 and MAP3K12, in addition to CRAF, could mediate this process by binding to RIT1. Moreover, RIT1 increased the phosphorylation of p38 MAPK and AKT to promote cell survival under reactive oxygen species stress. Based on this mechanistic understanding, we treated RIT1-overexpressing HCC with combined regimen sorafenib plus AKT inhibitor, and achieved enhanced antitumor effects in vivo. Our study reveals RAS "orphan" member RIT1 as the most common genetic alteration of RAS family in HCC and combination of sorafenib with AKT inhibitor might be a promising treatment strategy for RIT1-overexpressing HCC.