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As an evolutionarily conserved DNA-sensing machinery in innate immunity, the cGAS-STING pathway has been reported to play an important role in immune surveillance and tumor suppression. Recent evidence suggests an intriguing tumor- and metastasis-promoting effect of this signaling pathway, either in a cancer cell-autonomous or a cancer cell-nonautonomous, bystander cell-mediated manner. Here, we show a new face of cGAS-STING signaling whose activation in a cancer-cell-autonomous response manner confers drug resistance. Targeted or conventional chemotherapy drug treatment induced cancer cell cytosolic DNA accumulation and triggered subsequent cGAS-STING signaling activation in cancer cell lines and the human cell-derived xenograft tumors. This activation promoted an acquisition and maintenance of drug resistance which was prevented and overcome in vitro and in vivo by blockade of STING signaling. This finding highlights a new face of cGAS-STING signaling and an ability of cancer cells to hijack the evolutionarily conserved inflammatory signaling to counteract drug stress and warrants a caution in combining STING agonist with targeted or conventional chemotherapy drug treatment, a strategy prevailing in current clinical trials.Statement of significancecGAS-STING signaling has long been recognized as playing a key role in triggering antitumor immunity. We reveal a new face of cGAS-STING signaling and an ability of cancer cells autonomously to hijack the evolutionarily conserved inflammatory signaling to counteract drug stress.

Optimal operation of a compressor station is important since it accounts for 25 % to 50 % of a company’s total operating budget. In short-term management of a compressor station, handling demand uncertainty is important yet challenging. Previous studies either require precise information about the distribution of uncertain parameters or greatly simplify the compressor model. We build a two-stage robust optimization framework of power cost minimization in a natural gas compressor station with non-identical compressors. In the first stage, decision variables are the ON/OFF state of each compressor and discharge pressure. The worst-case cost of the second stage is incorporated in the first stage. First-stage decision variables feasibility is discussed and proper feasibility cuts are also proposed for the first stage. We employ a piece-wise approximation and propose accelerate methods. Our numerical results highlight two advantages of robust approach when managing uncertainty in practical settings: (1) the feasibility of first-stage decision can be increased by up to 45 % , and (2) the worst-case cost can be reduced by up to 25 % compared with stochastic programming models. Furthermore, our numerical experiments show that the designed accelerate algorithm has time improvements of 1518.9% on average (3785.9% at maximum).

Background: Acquired resistance to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) such as erlotinib is a major challenge to achieve an overall clinical benefit of the targeted therapy. Recently, aldehyde dehydrogenase 1 (ALDH1) induction has been found to render lung adenocarcinomas resistant to EGFR-TKIs, and targeting ALDH1A1 becomes a novel strategy to overcome resistance. However, the molecular mechanism underlying such effect remains poorly understood. Methods: Comprehensive assays were performed in a panel of lung adenocarcinoma cell lines and xenografts that acquired resistance to erlotinib. Cancer phenotype was evaluated by cell viability, apoptosis, migration, and epithelial-mesenchymal transition analysis in vitro, tumorsphere formation analysis ex vivo, and tumor growth and dissemination analysis in vivo. Reactive oxygen species (ROS) and reactive carbonyl species (RCS) were detected based on fluorescent oxidation indicator and liquid chromatography coupled to mass spectrometry, respectively. Protein target was suppressed by RNA interference and pharmacological inhibition or ecto-overexpressed by lentivirus-based cloning. Gene promoter activity was measured by dual-luciferase reporting assay. Results: Knockdown or pharmacological inhibition of ALDH1A1 overcame erlotinib resistance in vitro and in vivo. ALDH1A1 overexpression was sufficient to induce erlotinib resistance. Metabolomic analysis demonstrated lower ROS-RCS levels in ALDH1A1-addicted, erlotinib-resistant cells; in line with this, key enzymes for metabolizing ROS and RCS, SOD2 and GPX4, respectively, were upregulated in these cells. Knockdown of SOD2 or GPX4 re-sensitized the resistant cells to erlotinib and the effect was abrogated by ROS-RCS scavenging and mimicked by ROS-RCS induction. The ALDH1A1 overexpressed cells, though resisted erlotinib, were more sensitive to SOD2 or GPX4 knockdown. The ALDH1A1 effect on erlotinib resistance was abrogated by ROS-RCS induction and mimicked by ROS-RCS scavenging. Detection of GPX4 and SOD2 expression and analysis of promoter activities of GPX4 and SOD2 under the condition of suppression or overexpression of ALDH1A1 demonstrated that the RCS-ROS-metabolic pathway was controlled by the ALDH1A1-GPX4-SOD2 axis. The ROS-RCS metabolic dependence mechanism in ALDH1A1-induced resistance was confirmed in vivo. Analysis of public databases showed that in patients undergoing chemotherapy, those with high co-expression of ALDH1A1, GPX4, and SOD2 had a lower probability of survival. Conclusions: ALDH1A1 confers erlotinib resistance by facilitating the ROS-RCS metabolic pathway. ALDH1A1-induced upregulation of SOD2 and GPX4, as well as ALDH1A1 itself, mitigated erlotinib-induced oxidative and carbonyl stress, and imparted the TKI resistance. The elucidation of previously unrecognized metabolic mechanism underlying erlotinib resistance provides new insight into the biology of molecular targeted therapies and help to design improved pharmacological strategies to overcome the drug resistance.

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) have achieved satisfactory clinical effects in the therapy of non-small cell lung cancer (NSCLC), but acquired resistance limits their clinical application. NRF2 has been shown to enhance the resistance to apoptosis induced by radiotherapy and some chemotherapy. In this study, we investigated the role of NRF2 in resistance to EGFR-TKIs. We showed that NRF2 protein levels were markedly increased in a panel of EGFR-TKI-resistant NSCLC cell lines due to slow degradation of NRF2 protein. NRF2 knockdown overcame the resistance to EGFR-TKIs in HCC827ER and HCC827GR cells. Furthermore, we demonstrated that NRF2 imparted EGFR-TKIs resistance in HCC827 cells via upregulation of GPX4 and SOD2, and suppression of GPX4 and SOD2 reversed resistance to EGFR-TKIs. Thus, we conclude that targeting NRF2-GPX4/SOD2 pathway is a potential strategy for overcoming resistance to EGFR-TKIs.

A novel ubiquitin-like antitumour protein (RBUP) was isolated from fruiting bodies of the edible mushroom Ramaria botrytis. The protein was isolated with a purification protocol involving ion exchange chromatography on DEAE-Sepharose fast flow and gel filtration on Sephadex G-75. SDS-PAGE, Native-PAGE and ultracentrifugation analysis disclosed that RBUP was a monomeric protein with a molecular weight of 18.5 kDa. ESI–MS/MS demonstrated that it shared 69% amino acid sequence similarity with Coprinellus congregates ubiquitin (gi|136667). The protein exhibiting strong anticancer activity towards A549 cells. Analysis by employing AO/EB staining and Annexin V-FITC/PI detection indicated that the cytotoxic effect of RBUP was mediated through induction of apoptosis. Furthermore, RBUP displayed hemagglutinating and deoxyribonuclease activities. A temperature of 40 °C and pH of 7.0 were required for optimal DNase activity. Therefore, it was estimated that RBUP exerted its antitumour effect by inducing apoptosis, and its hemagglutinating and DNase activities were also thought to participate in this effect. These results demonstrated that RBUP was a multifunctional protein with potential medicinal applications.

OBJECTIVE Mesenchymal hamartoma of the liver (MHL) is a rare disease that makes up about 5%–8% of primitive hepatic tumors in children. The etiology of MHL has been the subject of considerable discussion. The possibility of malignant transformation of MHL is inclusive. To enhance the recognition of MHL in children, we have review the procedures in diagnosis and treatment and present 4 of our own cases. METHODS The clinical characteristics of MHL in 4 children including history, physical examination, lab examination, imaging data and pathology were analyzed and discussed and related to reports from the literature. RESULTS All the cases were diagnosed with B-ultrasonography and CT preoperatively, and were confirmed intra-operatively and histologically. Satisfactory results were reached postoperatively. CONCLUSION MHL is an uncommon benign lesion in children. The main presentation is abdominal painless mass. Diagnosis is aided with B-ultrasonography and CT preoperatively. Complete tumor removal is the best choice for MHL treatment resulting in a good outcome.

A 4-year-old girl was admitted with a history of abdominal pain for 10 days. Abdominal US showed a large solid mass with homogeneously increased echogenicity. Contrastenhanced CT showed a large, well-defined multilocular mass of largely fat density with enhancing septa occupying most of the abdominal cavity (Fig. 1). Microscopically, the tumor was made up of lobules of mature and immature fat cells and typical lipoblasts with large, atypical and vacuolated nuclei, confirming the diagnosis of a mesenteric lipoblastoma (Fig. 2). Lipoblastoma arising in the mesentery is extremely rare. Although preoperative imaging might be useful to assess the extent of disease and aid in planning surgical resection, it is of little help in differentiating lipomatous tumors [1, 2].