Unraveling radiation-induced skeletal muscle damage: Insights from a 3D human skeletal muscle organoid model.

BACKGROUND: Three-dimensional (3D) organoids derived from human pluripotent stem cells (hPSCs) have revolutionized in vitro tissue modeling, offering a unique opportunity to replicate physiological tissue organization and functionality. This study investigates the impact of radiation on skeletal muscle response using an innovative in vitro human 3D skeletal muscle organoids (hSMOs) model derived from hPSCs. METHODS: The hSMOs model was established through a differentiation protocol faithfully recapitulating embryonic myogenesis and maturation via paraxial mesodermal differentiation of hPSCs. Key skeletal muscle characteristics were confirmed using immunofluorescent staining and RT-qPCR. Subsequently, the hSMOs were exposed to a clinically relevant dose of 2 Gy of radiation, and their response was analyzed using immunofluorescent staining and RNA-seq. RESULTS: The hSMO model faithfully recapitulated embryonic myogenesis and maturation, maintaining key skeletal muscle characteristics. Following exposure to 2 Gy of radiation, histopathological analysis revealed deficits in hSMOs expansion, differentiation, and repair response across various cell types at early (30 min) and intermediate (18 h) time points post-radiation. Immunofluorescent staining targeting γH2AX and 53BP1 demonstrated elevated levels of foci per cell, particularly in PAX7+ cells, during early and intermediate time points, with a distinct kinetic pattern showing a decrease at 72 h. RNA-seq data provided comprehensive insights into the DNA damage response within the hSMOs. CONCLUSIONS: Our findings highlight deficits in expansion, differentiation, and repair response in hSMOs following radiation exposure, enhancing our understanding of radiation effects on skeletal muscle and contributing to strategies for mitigating radiation-induced damage in this context.

In vitro modeling of skeletal muscle ischemia-reperfusion injury based on sphere differentiation culture from human pluripotent stem cells.

Skeletal muscle ischemia-reperfusion (IR) injury poses significant challenges due to its local and systemic complications. Traditional studies relying on two-dimensional (2D) cell culture or animal models often fall short of faithfully replicating the human in vivo environment, thereby impeding the translational process from animal research to clinical applications. Three-dimensional (3D) constructs, such as skeletal muscle spheroids with enhanced cell-cell interactions from human pluripotent stem cells (hPSCs) offer a promising alternative by partially mimicking human physiological cellular environment in vivo processes. This study aims to establish an innovative in vitro model, human skeletal muscle spheroids based on sphere differentiation from hPSCs, to investigate human skeletal muscle developmental processes and IR mechanisms within a controlled laboratory setting. By eticulously recapitulating embryonic myogenesis through paraxial mesodermal differentiation of neuro-mesodermal progenitors, we successfully established 3D skeletal muscle spheroids that mirror the dynamic colonization observed during human skeletal muscle development. Co-culturing human skeletal muscle spheroids with spinal cord spheroids facilitated the formation of neuromuscular junctions, providing functional relevance to skeletal muscle spheroids. Furthermore, through oxygen-glucose deprivation/re-oxygenation treatment, 3D skeletal muscle spheroids provide insights into the molecular events and pathogenesis of IR injury. The findings presented in this study significantly contribute to our understanding of skeletal muscle development and offer a robust platform for in vitro studies on skeletal muscle IR injury, holding potential applications in drug testing, therapeutic development, and personalized medicine within the realm of skeletal muscle-related pathologies.

Event-related potential response to drivers' facial expressions in an online car-hailing scene.

Recognizing facial expressions is crucial for adaptive social interaction. Prior empirical research on facial expression processing has primarily focused on isolated faces; however, facial expressions appear embedded in surrounding scenes in everyday life. In this study, we attempted to demonstrate how the online car-hailing scene affects the processing of facial expression. This study examined the processing of drivers' facial expressions in scenes by recording event-related potentials, in which neutral or happy faces embedded in online car-hailing orders were constructed (with type of vehicle, driver rating, driver surname, and level of reputation controlled). A total of 35 female volunteers participated in this experiment and were asked to judge which facial expressions that emerged in scenes of online car-hailing were more trustworthy. The results revealed an interaction between facial expression scenes, brain areas, and electrode sites in the late positive potential, which indicated that happy faces elicited larger amplitudes than did neutral ones in the parietal areas and that scenes with happy facial expressions had shorter latencies than did those with neutral ones. As expected, the late positive potential evoked by happy facial expressions in a scene was larger than that evoked by neutral ones, which reflected motivated attention and motivational response processes. This study highlights the importance of scenes as context in the study of facial expression processing.

Real-world overall survival of patients receiving cetuximab in later lines of treatment for metastatic colorectal cancer.

Aim: To examine characteristics of and treatment duration and real-world overall survival (rwOS) in patients receiving cetuximab as second-line (2L) or third-line (3L) treatment for metastatic colorectal cancer. Materials & methods: This was a retrospective study of 1096 and 684 patients in 2L and 3L cohorts, respectively. Results: The most common cetuximab-based regimens were cetuximab + folinic acid, fluorouracil and irinotecan (2L: 44%; 3L: 32%) and cetuximab + irinotecan (2L: 28%; 3L: 35%). Kaplan-Meier survival estimates and stepwise Cox regression model analysis demonstrated median treatment duration and rwOS of 3.7 and 14.4 months, respectively, in patients receiving treatment in the 2L cohort. In the 3L cohort, treatment duration was 3.3 months and rwOS was 12.0 months. Conclusion: This large real-world study provides evidence of rwOS in patients with metastatic colorectal cancer receiving cetuximab-based regimens as 2L or 3L treatment.

In this retrospective study, the authors examined baseline characteristics of and treatment duration and real-world overall survival (rwOS) in 1096 and 684 patients with metastatic colorectal cancer receiving cetuximab as second-line (2L) and third-line (3L) treatment, respectively. The most common cetuximab-based regimens were cetuximab + folinic acid, fluorouracil and irinotecan (2L: 44%; 3L: 32%) and cetuximab + irinotecan (2L: 28%; 3L: 35%). Median treatment duration and rwOS were 3.7 and 14.4 months, respectively, in patients receiving treatment in the 2L cohort. In the 3L cohort, median treatment duration was 3.3 months and rwOS was 12.0 months. This large real-world study provides evidence of rwOS in patients with metastatic colorectal cancer receiving cetuximab-based regimens as 2L or 3L treatment.

Canonical Wnt signaling works downstream of iron overload to prevent ferroptosis from damaging osteoblast differentiation.

Excessive iron has emerged in a large population of patients suffering from degenerative or hematological diseases with a common outcome, osteoporosis. However, its underlying mechanism remains to be clarified in order to formulate effective prevention and intervention against the loss of bone-forming osteoblasts. We show herein that increased intracellular iron by ferric ammonium citrate (FAC) mimicking the so-called non-transferrin bound iron concentrations leads to ferroptosis and impaired osteoblast differentiation. FAC upregulates the expression of Trfr and DMT1 genes to increase iron uptake, accumulating intracellular labile ferrous iron for iron overload status. Then, the excessive ferrous iron generates reactive oxygen species (ROS) and lipid peroxidation products (LPO), causing ferroptosis with its typical mitochondrial morphological changes, such as shrinkaged and condensed membrane with diminution and loss of crista and outer membrane rupture. We further examined that ferroptosis is the main cause responsible for FAC-disrupted osteoblast differentiation, although apoptosis and senescence are concurrently induced as well. Mechanistically, we revealed that iron dose-dependently down-regulates the expression of Wnt target genes and inhibits the transcription of Wnt reporter TopFlash construct, so as to inhibit the canonical Wnt signaling. Wnt agonist, ferroptosis inhibitor, or antioxidant melatonin reverses iron-inhibited canonical Wnt signaling to restore osteoblast differentiation by reducing ROS and LPO production to prevent ferroptosis notably without reducing iron overload. This study proposes a working model against excessive iron-induced osteoporosis: iron chelator deferoxamine or the above three drugs prevent ferroptosis, restore traditional Wnt signaling to maintain osteoblast differentiation no matter whether iron overload is removed or not. Additionally, iron chelator should be used to a suitable extent because iron itself is necessary for osteogenic differentiation.

Defining treatment regimens and lines of therapy using real-world data in oncology.

Retrospective observational research relies on databases that do not routinely record lines of therapy or reasons for treatment change. Standardized approaches to estimate lines of therapy were developed and evaluated in this study. A number of rules were developed, assumptions varied and macros developed to apply to large datasets. Results were investigated in an iterative process to refine line of therapy algorithms in three different cancers (lung, colorectal and gastric). Three primary factors were evaluated and included in the estimation of lines of therapy in oncology: defining a treatment regimen, addition/removal of drugs and gap periods. Algorithms and associated Statistical Analysis Software (SAS®) macros for line of therapy identification are provided to facilitate and standardize the use of real-world databases for oncology research.

Lay abstract Most, if not all, real-world healthcare databases do not contain data explaining treatment changes, requiring that rules be applied to estimate when treatment changes may reflect advancement of underlying disease. This study investigated three tumor types (lung, colorectal and gastric cancer) to develop and provide rules that researchers can apply to real-world databases. The resulting algorithms and associated SAS^® macros from this work are provided for use in the Supplementary data.

Patient Experience After Receiving a Diagnosis of Gastric Cancer in the USA.

PURPOSE: This study investigated the patient perspective during cancer treatment and throughout the survivorship period and to understand how the patient experience may be related to choices for the treatment of gastric cancer. METHODS: Eligible patients in the Vector Oncology electronic medical records database were ≥18 years of age, diagnosed with gastric cancer, and received active treatment. Quality of life (QOL) was collected using the Patient Care Monitor (PCM). Time to deterioration in QOL and overall survival were measured, adjusting for demographic and baseline clinical characteristics. Logistic regression model and classification and regression trees (CART) were used to identify factors associated with treatment choice. RESULTS: There were 776 patients in this study, of whom 301 (38.8%) reported QOL data. Most patients reported problems on all PCM subscales; problems were more common during the treatment period. Median time to deterioration of PCM subscales ranged from 42 days for treatment side effects to 331 days for impaired performance. Median survival was low: 6.9 and 5.5 months from the start of first- and second-line therapy, respectively. The choices made between therapeutic options were primarily associated with the site at which the oncologist practiced. CONCLUSIONS: Patients with gastric cancer report a considerable number of concerns on all subscales of the PCM, particularly during active treatment periods. The treatment heterogeneity and relative lack of clinical and symptom- or QOL-related factors associated with treatment choice suggest a gap in evidence that must be filled.

Current and projected patient and insurer costs for the care of patients with non-small cell lung cancer in the United States through 2040.

AIMS: The objective of this study was to quantify the current and to project future patient and insurer costs for the care of patients with non-small cell lung cancer in the US. MATERIALS AND METHODS: An analysis of administrative claims data among patients diagnosed with non-small cell lung cancer from 2007-2015 was conducted. Future costs were projected through 2040 based on these data using autoregressive models. RESULTS: Analysis of claims data found the average total cost of care during first- and second-line therapy was $1,161.70 and $561.80 for patients, and $45,175.70 and $26,201.40 for insurers, respectively. By 2040, the average total patient out-of-pocket costs are projected to reach $3,047.67 for first-line and $2,211.33 for second-line therapy, and insurance will pay an average of $131,262.39 for first-line and $75,062.23 for second-line therapy. LIMITATIONS: Claims data are not collected for research purposes; therefore, there may be errors in entry and coding. Additionally, claims data do not contain important clinical factors, such as stage of disease at diagnosis, tumor histology, or data on disease progression, which may have important implications on the cost of care. CONCLUSIONS: The trajectory of the cost of lung cancer care is growing. This study estimates that the cost of care may double by 2040, with the greatest proportion of increase in patient out-of-pocket costs. Despite the average cost projections, these results suggest that a small sub-set of patients with very high costs could be at even greater risk in the future.