Augmented drug resistance of osteosarcoma cells within decalcified bone matrix scaffold: The role of glutamine metabolism.

Due to the lack of a precise in vitro model that can mimic the nature microenvironment in osteosarcoma, the understanding of its resistance to chemical drugs remains limited. Here, we report a novel three-dimensional model of osteosarcoma constructed by seeding tumor cells (MG-63 and MNNG/HOS Cl no. 5) within demineralized bone matrix scaffolds. Demineralized bone matrix scaffolds retain the original components of the natural bone matrix (hydroxyapatite and collagen type I), and possess good biocompatibility allowing osteosarcoma cells to proliferate and aggregate into clusters within the pores. Growing within the scaffold conferred elevated resistance to doxorubicin on MG-63 and MNNG/HOS Cl no. 5 cell lines as compared to two-dimensional cultures. Transcriptomic analysis showed an increased enrichment for drug resistance genes along with enhanced glutamine metabolism in osteosarcoma cells in demineralized bone matrix scaffolds. Inhibition of glutamine metabolism resulted in a decrease in drug resistance of osteosarcoma, which could be restored by α-ketoglutarate supplementation. Overall, our study suggests that microenvironmental cues in demineralized bone matrix scaffolds can enhance osteosarcoma drug responses and that targeting glutamine metabolism may be a strategy for treating osteosarcoma drug resistance.

Prevalence, Causes, and Risk Factors of Presenting Visual Impairment and Presenting Blindness in Adults Presenting to an Examination Center in Suzhou, China.

Purpose: To evaluate the prevalence, causes, and risk factors of presenting visual impairment (PVI) and presenting blindness among adults in Suzhou, China. Methods: A total of 43927 subjects were included in this cross-sectional study. Each subject underwent ophthalmic examinations, including presenting visual acuity (PVA), intraocular pressure (IOP), slit-lamp examination, and fundus examination under the small pupils of each eye. Results: Using the World Health Organization (WHO) definition, the prevalence of bilateral PVI, bilateral presenting blindness, monocular PVI, and monocular presenting blindness was 1.59% (95% CI, 1.51-1.67), 0.002% (95% CI, 0.0019-0.0021), 3.87% (95% CI, 3.68-4.06), and 0.19% (95% CI, 0.18-0.20), respectively. Using the United States (US) definition, the prevalence of bilateral PVI, bilateral presenting blindness, monocular PVI, and monocular presenting blindness was 5.83% (95% CI, 5.54-6.12), 0.04% (95% CI, 0.038-0.042), 7.43% (95% CI, 7.06-7.80), and 0.45% (95% CI, 0.43-0.47), respectively. The prevalence of PVI was higher in females (WHO criteria, 2.06%, 95% CI, 1.96-2.16; US criteria, 7.27%, 95% CI, 6.91-7.63) than in males (WHO criteria, 1.2%, 95 CI%, 1.14-1.26; US criteria, 4.65%, 95% CI, 4.42-4.89). The leading cause of PVI is an uncorrected refractive error, followed by cataracts and age-related macular degeneration (AMD). Multivariate analysis proved that the prevalence of visual impairment (PVA, better eye, WHO criteria) increased significantly with older age, higher mean arterial pressure (MAP), higher globulin level, and higher fasting blood glucose (FBG). In addition, it also increased significantly with lower hemoglobin, a lower body mass index (BMI), and a lower arterial stiffness index. In this study, serum creatinine, blood urea nitrogen, uric acid, triglycerides, and the systemic immune-inflammation index (SII) showed no association with visual impairment. Conclusion: The leading causes of PVI in Suzhou were uncorrected refractive error and cataracts. The prevalence of PVI increased with females, older age, higher MAP, higher FBG, higher globulin, lower hemoglobin, lower BMI, and lower arterial stiffness index.

Drug resistance mechanisms and progress in the treatment of EGFR-mutated lung adenocarcinoma.

According to global cancer data, lung cancer was the leading cause of cancer-related death in 2020. With the diversification of treatment strategies, the survival outcomes of patients with advanced lung cancer have improved significantly, but the 5-year overall survival rate remains <20%. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the preferred treatment for lung adenocarcinoma patients with EGFR-sensitive mutations; however, acquired drug resistance is inevitable. Osimertinib (a third-generation EGFR inhibitor) is the most commonly used drug for cancers with a secondary T790M mutation. Unfortunately, acquired drug resistance against third-generation drugs still emerges. The C797s mutation is the primary acquired resistance mechanism against Osimertinib. Research on fourth-generation EGFR-TKI drugs with a C797s mutation is currently at various experimental stages, and no drug has been approved for clinical use. In addition to the resistance mechanisms described above, HER2 amplification, MET amplification, PIK3A mutation, KRAS mutation, BRAF mutation, transformation to small cell lung cancer, transformation to lung squamous cell carcinoma, and EMT have been reported as mechanisms of acquired drug resistance to first-, second- and third-generation EGFR-TKIs. These mechanisms are noted in a relatively high proportion of tumors, but treatment options are limited. In recent years, immunotherapy has made progress in the treatment of several cancers, including advanced EGFR-mutated non-small cell lung cancer (NSCLC). Due to the relatively high frequency of EGFR mutation in patients with lung adenocarcinoma in China, an increased number of patients develop EGFR-TKI resistance, and subsequent treatment options are critical. This article reviews the mechanisms of drug resistance to different EGFR-TKIs and treatment progression, providing ideas for the follow-up treatment for EGFR-resistant patients.

Dual functions of microRNA-17 in maintaining cartilage homeostasis and protection against osteoarthritis.

Damaged hyaline cartilage has no capacity for self-healing, making osteoarthritis (OA) "difficult-to-treat". Cartilage destruction is central to OA patho-etiology and is mediated by matrix degrading enzymes. Here we report decreased expression of miR-17 in osteoarthritic chondrocytes and its deficiency contributes to OA progression. Supplementation of exogenous miR-17 or its endogenous induction by growth differentiation factor 5, effectively prevented OA by simultaneously targeting pathological catabolic factors including matrix metallopeptidase-3/13 (MMP3/13), aggrecanase-2 (ADAMTS5), and nitric oxide synthase-2 (NOS2). Single-cell RNA sequencing of hyaline cartilage revealed two distinct superficial chondrocyte populations (C1/C2). C1 expressed physiological catabolic factors including MMP2, and C2 carries synovial features, together with C3 in the middle zone. MiR-17 is highly expressed in both superficial and middle chondrocytes under physiological conditions, and maintains the physiological catabolic and anabolic balance potentially by restricting HIF-1α signaling. Together, this study identified dual functions of miR-17 in maintaining cartilage homeostasis and prevention of OA.

Clinical Efficacy of Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer Patients with Liver Metastases: A Network Meta-Analysis of Nine Randomized Controlled Trials.

PURPOSE: This network meta-analysis (NMA) was conducted to compare the efficacy of immune checkpoint inhibitors in advanced non-small cell lung cancer (NSCLC) patients with liver metastases. MATERIALS AND METHODS: English literature was retrieved from the PubMed, American Society of Clinical Oncology, and European Society for Medical Oncology databases from January 2015 to January 2021. We pooled the overall survival (OS) and progression-free survival (PFS) hazard ratios (HRs) using an NMA and ranked treatments by the surface under the cumulative ranking curve. Publication bias was evaluated by Begg's and Egger's tests. STATA 15.0 was used for the sensitivity analysis, and the remaining statistical analyses were performed using R 4.0.2. RESULTS: Nine eligible phase III randomized controlled trials were included, including 1,141 patients with liver metastases. Pembrolizumab+chemotherapy ranked highest, followed by atezolizumab+bevacizumab+chemotherapy and nivolumab. However, no significant difference in OS rates was observed across these three treatments (HR, 0.98; 95% confidence interval [CI], 0.43 to 2.22 for pembrolizumab+chemotherapy vs. atezolizumab+bevacizumab+chemotherapy; HR, 0.91; 95% CI, 0.52 to 1.57 for pembrolizumab+chemotherapy vs. nivolumab). Regarding the PFS rate, atezolizumab+bevacizumab+chemotherapy and pembro-lizumab+chemotherapy ranked highest and no significant difference was observed between them (HR, 0.79; 95% CI, 0.36 to 1.70 for atezolizumab+bevacizumab+chemotherapy vs. pembrolizumab+chemotherapy). CONCLUSION: Pembrolizumab+chemotherapy, atezolizumab+bevacizumab+chemotherapy, and nivolumab were superior to other treatments in NSCLC patients with liver metastases. These new findings may help clinicians better select therapeutic strategies for NSCLC patients with liver metastases.

Fermentation supernatant of Staphylococcus aureus drives catabolism in chondrocytes via NF-κB signaling mediated increase of cholesterol metabolism.

Septic arthritis induced by Staphylococcus aureus (S. aureus) causes irreversible cartilage degradation and subsequent permanent joint dysfunction. Recently, cartilage degradation in osteoarthritis is recognized to be associated with metabolic disorders. However, whether cholesterol metabolism is linked to septic arthritis pathology remains largely unknown. Here, we found that exposure to fermentation supernatant (FS) of S. aureus in chondrocytes resulted in a significant increase in expression of key modulators involved in cholesterol metabolism, including lectin-type oxidized low density lipoprotein receptor 1 (LOX1), cholesterol 25-hydroxylase (CH25H), 25- hydroxycholesterol 7α-hydroxylase (CYP7B1) as well as retinoic acid-related orphan receptor alpha (RORα), a binding receptor for cholesterol metabolites. We further demonstrated that enhancement of CH25H/CYP7B1/RORα axis resulted from FS exposure was mediated by activation of NF-κB signaling, along with upregulation in catabolic factors including matrix metallopeptidases (MMP3 and MMP13), aggrecanase-2 (ADAMTS5), and nitric oxide synthase-2 (NOS2) in chondrocytes. Exogenous cholesterol acts synergistically with FS in activating NF-κB pathway and increases cholesterol metabolism. While, the addition of tauroursodeoxycholic acid (TUDCA) which promotes cholesterol efflux, resulted in remarkable reduction of intracellular cholesterol level and restoration of balance between anabolism and catabolism in FS treated chondrocytes. Collectively, our data indicated that, in response to FS of S. aureus, NF-κB signaling activation coupled with increased cholesterol metabolism to stimulate catabolic factors in chondrocytes, highlighting cholesterol metabolism as a potential therapeutic target for treating septic arthritis.

Effect of Community Screening on the Demographic Makeup and Clinical Severity of Glaucoma Patients Receiving Care in Urban China.

PURPOSE: To assess differences in clinical and demographic characteristics between glaucoma patients identified by community screening and those newly diagnosed in hospital in a Chinese setting. DESIGN: Prospective comparative cohort study. METHODS: A total of 373 patients identified with glaucoma among 27 000 persons undergoing community screening were enrolled as the Screening group. The Clinic group consisted of 119 consecutively presenting, newly diagnosed glaucoma patients in hospital. Primary outcomes were mean deviation (MD), visual field index (VFI) and pattern standard deviation (PSD) on Humphrey Field Analyzer, and intraocular pressure (IOP). Disease severity was categorized into 5 stages based on MD. RESULTS: A total of 89.6% (328/373) of Screening group patients had IOP < 21 mm Hg, compared to 48.7% (58/119) in the Clinic group (P < .001). The mean VFI, MD, and PSD were 76.4% ± 23.8%, -9.7 ± 7.3 dB, and 6.4 ± 3.4 dB in the Screening group and significantly worse in the Clinic group: 44.1% ± 32.0%, -19.8 ± 9.5 dB, and 7.6 ± 3.1 dB (P < .001 for MD and VFI, P = .001 for PSD). Nearly three quarters of Screening patients had early or moderate visual field loss (monocular), while nearly half of Clinic patients had severe loss at the time of diagnosis. Screening patients were significantly more likely to be older (P < .001) and female (P < .001) than Clinic patients. CONCLUSION: Glaucoma patients detected through community screening had significantly milder damage, and were more likely to include underserved groups (women, elderly) than those newly diagnosed in a clinic in this setting. Comparison with population studies suggests that cases of glaucoma with IOP < 21 mm Hg are severely underascertained in China, a situation that may be improved by screening.