Relative biological effectiveness of clinically relevant photon energies for the survival of human colorectal, cervical, and prostate cancer cell lines.

Objective:Relative biological effectiveness (RBE) differs between radiation qualities. However, an RBE of 1.0 has been established for photons regardless of the wide range of photon energies used clinically, the lack of reproducibility in radiobiological studies, and outdated reference energies used in the experimental literature. Moreover, due to intrinsic radiosensitivity, different cancer types have different responses to radiation. This study aimed to characterize the RBE of clinically relevant high and low photon energiesin vitrofor three human cancer cell lines: HCT116 (colon), HeLa (cervix), and PC3 (prostate).Approach:Experiments were conducted following dosimetry protocols provided by the American Association of Physicists in Medicine. Cells were irradiated with 6 MV x-rays, an192Ir brachytherapy source, 225 kVp and 50 kVp x-rays. Cell survival post-irradiation was assessed using the clonogenic assay. Survival fractions were fitted using the linear quadratic model, and the survival curves were generated for RBE calculations.Main results:The cell killing was more efficient with decreasing photon energy: the HCT116 RBESF0.1for 6 MV x-rays,192Ir, and 50 kVp x-rays using 225 kVp x-rays as the reference were 0.89 ± 0.03, 0.95 ± 0.03, and 1.24 ± 0.04; the HeLa RBESF0.1were 0.95 ± 0.04, 0.97 ± 0.05, and 1.09 ± 0.03, and the PC3 RBESF0.1were 0.84 ± 0.01, 0.84 ± 0.01, and 1.13 ± 0.02, respectively. HeLa and PC3 cells had varying radiosensitivity when irradiated with 225 and 50 kVp x-rays.Significance:This difference supports the notion that RBE may not be 1.0 for all photons through experimental investigations that employed precise dosimetry. It highlights that different cancer types may not have identical responses to the same irradiation quality. Additionally, the RBE of clinically relevant photons was updated to the reference energy of 225 kVp x-rays.

DNA break clustering as a predictor of cell death across various radiation qualities: influence of cell size, cell asymmetry, and beam orientation.

Cosmic radiation, composed of high charge and energy (HZE) particles, causes cellular DNA damage that can result in cell death or mutation that can evolve into cancer. In this work, a cell death model is applied to several cell lines exposed to HZE ions spanning a broad range of linear energy transfer (LET) values. We hypothesize that chromatin movement leads to the clustering of multiple double strand breaks (DSB) within one radiation-induced foci (RIF). The survival probability of a cell population is determined by averaging the survival probabilities of individual cells, which is function of the number of pairwise DSB interactions within RIF. The simulation code RITCARD was used to compute DSB. Two clustering approaches were applied to determine the number of RIF per cell. RITCARD outputs were combined with experimental data from four normal human cell lines to derive the model parameters and expand its predictions in response to ions with LET ranging from ~0.2 keV/µm to ~3000 keV/µm. Spherical and ellipsoidal nuclear shapes and two ion beam orientations were modeled to assess the impact of geometrical properties on cell death. The calculated average number of RIF per cell reproduces the saturation trend for high doses and high-LET values that is usually experimentally observed. The cell survival model generates the recognizable bell shape of LET dependence for the relative biological effectiveness (RBE). At low LET, smaller nuclei have lower survival due to increased DNA density and DSB clustering. At high LET, nuclei with a smaller irradiation area-either because of a smaller size or a change in beam orientation-have a higher survival rate due to a change in the distribution of DSB/RIF per cell. If confirmed experimentally, the geometric characteristics of cells would become a significant factor in predicting radiation-induced biological effects. Insight Box: High-charge and energy (HZE) ions are characterized by dense linear energy transfer (LET) that induce unique spatial distributions of DNA damage in cell nuclei that result in a greater biological effect than sparsely ionizing radiation like X-rays. HZE ions are a prominent component of galactic cosmic ray exposure during human spaceflight and specific ions are being used for radiotherapy. Here, we model DNA damage clustering at sub-micrometer scale to predict cell survival. The model is in good agreement with experimental data for a broad range of LET. Notably, the model indicates that nuclear geometry and ion beam orientation affect DNA damage clustering, which reveals their possible role in mediating cell radiosensitivity.

Impact of dietary ingredients on radioprotection and radiosensitization: a comprehensive review.

Radiation exposure poses significant health risks, particularly in radiotherapy and nuclear accidents. Certain dietary ingredients offer potential radioprotection and radiosensitization. In this review, we explore the impact of dietary ingredients, including vitamins, minerals, antioxidants, and other bioactive compounds, on radiation sensitivity and their potential for radioprotection. Radiosensitizers reoxygenate hypoxic tumor cells, increase the radiolysis of water molecules, and regulate various molecular mechanisms to induce cytotoxicity and inhibit DNA repair in irradiated tumor cells. Several dietary ingredients, such as vitamins C, E, selenium, and phytochemicals, show promise in protecting against radiation by reducing radiation-induced oxidative stress, inflammation, and DNA damage. Radioprotectors, such as ascorbic acid, curcumin, resveratrol, and genistein, activate and modulate various signaling pathways, including Keap1-Nrf2, NF-κB, PI3K/Akt/mammalian target of rapamycin (mTOR), STAT3, and mitogen-activated protein kinase (MAPK), in response to radiation-induced oxidative stress, regulating inflammatory cytokine expression, and promoting DNA damage repair and cell survival. Conversely, natural dietary radiosensitizers impede these pathways by enhancing DNA damage and inducing apoptosis in irradiated tumor cells. Understanding the molecular basis of these effects may aid in the development of effective strategies for radioprotection and radiosensitization in cancer treatment. Dietary interventions have the potential to enhance the efficacy of radiation therapy and minimize the side effects associated with radiation exposure.

Human NGF "Painless" Ocular Delivery for Retinitis Pigmentosa: An In Vivo Study.

Retinitis pigmentosa (RP) is a family of genetically heterogeneous diseases still without a cure. Despite the causative genetic mutation typically not expressed in cone photoreceptors, these cells inevitably degenerate following the primary death of rods, causing blindness. The reasons for the "bystander" degeneration of cones are presently unknown but decrement of survival factors, oxidative stress, and inflammation all play a role. Targeting these generalized biological processes represents a strategy to develop mutation-agnostic therapies for saving vision in large populations of RP individuals. A classical method to support neuronal survival is by employing neurotrophic factors, such as NGF. This study uses painless human NGF (hNGFp), a TrkA receptor-biased variant of the native molecule with lower affinity for nociceptors and limited activity as a pain inducer; the molecule has identical neurotrophic power of the native form but a reduced affinity for the p75NTR receptors, known to trigger apoptosis. hNGFp has a recognized activity on brain microglial cells, which are induced to a phenotype switch from a highly activated to a more homeostatic configuration. hNGFp was administered to RP-like mice in vivo with the aim of decreasing retinal inflammation and also providing retinal neuroprotection. However, the ability of this treatment to counteract the bystander degeneration of cones remained limited.

Biophysical modeling of low-energy ion irradiations with NanOx.

BACKGROUND: Targeted radiotherapies with low-energy ions show interesting possibilities for the selective irradiation of tumor cells, a strategy particularly appropriate for the treatment of disseminated cancer. Two promising examples are boron neutron capture therapy (BNCT) and targeted radionuclide therapy with α $\alpha$ -particle emitters (TAT). The successful clinical translation of these radiotherapies requires the implementation of accurate radiation dosimetry approaches able to take into account the impact on treatments of the biological effectiveness of ions and the heterogeneity in the therapeutic agent distribution inside the tumor cells. To this end, biophysical models can be applied to translate the interactions of radiations with matter into biological endpoints, such as cell survival. PURPOSE: The NanOx model was initially developed for predicting the cell survival fractions resulting from irradiations with the high-energy ion beams encountered in hadrontherapy. We present in this work a new implementation of the model that extends its application to irradiations with low-energy ions, as the ones found in TAT and BNCT. METHODS: The NanOx model was adapted to consider the energy loss of primary ions within the sensitive volume (i.e., the cell nucleus). Additional assumptions were introduced to simplify the practical implementation of the model and reduce computation time. In particular, for low-energy ions the narrow-track approximation allowed to neglect the energy deposited by secondary electrons outside the sensitive volume, increasing significantly the performance of simulations. Calculations were performed to compare the original hadrontherapy implementation of the NanOx model with the present one in terms of the inactivation cross sections of human salivary gland cells as a function of the kinetic energy of incident α $\alpha$ -particles. RESULTS: The predictions of the previous and current versions of NanOx agreed for incident energies higher than 1 MeV/n. For lower energies, the new NanOx implementation predicted a decrease in the inactivation cross sections that depended on the length of the sensitive volume. CONCLUSIONS: We reported in this work an extension of the NanOx biophysical model to consider irradiations with low-energy ions, such as the ones found in TAT and BNCT. The excellent agreement observed at intermediate and high energies between the original hadrontherapy implementation and the present one showed that NanOx offers a consistent, self-integrated framework for describing the biological effects induced by ion irradiations. Future work will focus on the application of the latest version of NanOx to cases closer to the clinical setting.

Therapeutic Correlation of TLR-4 Mediated NF-κB Inflammatory Pathways in Ischemic Injuries.

Ischemia-reperfusion (I/R) injury refers to the tissue damage that happens when blood flow returns to tissue after a period of ischemia. I/R injuries are implicated in a large array of pathological conditions, such as cerebral, myocardial, renal, intestinal, retinal and hepatic ischemia. The hallmark of these pathologies is excessive inflammation. Toll-like receptors (TLRs) are recognized as significant contributors to inflammation caused by pathogens and, more recently, inflammation caused by injury. TLR-4 activation initiates a series of events that results in activation of nuclear factor kappa-B (NF-κB), which stimulates the production of pro-inflammatory cytokines and chemokines, exacerbating tissue injury. Therefore, through a comprehensive review of current research and experimentation, this investigation elucidates the TLRs signalling pathway and the role of TLR-4/NF-κB in the pathophysiology of I/R injuries. Furthermore, this review highlights the various pharmacological agents (TLR-4/NF-κB inhibitors) with special emphasis on the various ischemic injuries (cerebral, myocardial, renal, intestinal, retinal and hepatic). Future research should prioritise investigating the specific molecular pathways that cause TLR-4/NF-κBmediated inflammation in ischemic injuries. Additionally, efforts should be made to enhance treatment approaches in order to enhance patient outcomes.

Effect of photobiomodulation therapy with 660 and 980 nm diode lasers on differentiation of periodontal ligament mesenchymal stem cells.

This study aimed to compare the effects of photobiomodulation therapy (PBMT) with 660 and 980 nm diode lasers on differentiation of periodontal ligament mesenchymal stem cells (PDLMSCs). In this in vitro, experimental study, PDLMSCs were obtained from the Iranian Genetic Bank and cultured in osteogenic medium. They were then subjected to irradiation of 660 and 980 nm diode lasers, and their viability was assessed after one, two, and three irradiation cycles using the methyl thiazolyl tetrazolium (MTT) assay. The cells also underwent DAPI staining, cell apoptosis assay by using the Annexin V/PI, Alizarin Red staining, and real-time polymerase chain reaction (PCR) for assessment of the expression of osteogenic genes. Data were analyzed by two-way ANOVA. The two laser groups had no significant difference in cell apoptosis according to the results of DAPI staining. Both laser groups showed higher cell viability in the MTT assay at 4 and 6 days compared with the control group. Annexin V/PI results showed higher cell viability in both laser groups at 4 days compared with the control group. Rate of early and late apoptosis was lower in both laser groups than the control group at 4 days. Necrosis had a lower frequency in 980 nm laser group than the control group on day 6. Alizarin Red staining showed higher cell differentiation in both laser groups after 3 irradiation cycles than the control group. The highest expression of osteopontin (OPN), osteocalcin (OCN), and Runt-related transcription factor 2 (RUNX2) was noted in 660 nm laser group with 3 irradiation cycles at 14 days, compared with the control group. PBMT with 660 and 980 nm diode lasers decreased apoptosis and significantly increased PDLMSC differentiation after 3 irradiation cycles.

Fgf9 promotes incisor dental epithelial stem cell survival and enamel formation.

BACKGROUND: Understanding the role of cytokines in tooth development is critical for advancing dental tissue engineering. Fibroblast growth factor 9 (FGF9) is the only FGF consistently expressed throughout dental epithelial tissue, from the initiation of tooth bud formation to tooth maturation. However, mice lacking Fgf9 (Fgf9-/-) surprisingly show no obvious abnormalities in tooth development, suggesting potential compensation by other FGFs. Here we report findings from an Fgf9S99N mutation mouse model, a loss-of-function mutation with a dominant negative effect. Our study reveals that Fgf9 is crucial for dental epithelial stem cell (DESC) survival and enamel formation. METHODS: To dissect the role of Fgf9 in tooth development, we performed the micro-CT, histomorphological analysis and gene expression assay in mice and embryos with S99N mutation. In addition, we assessed the effect of FGF9 on the DESC survival and dental epithelial differentiation by DESC sphere formation assay and tooth explant culture. Cell/tissue culture methods, gene expression analysis, specific inhibitors, and antibody blockage analysis were employed to explore how Fgf9 regulates enamel differentiation and DESC survival through both direct and indirect mechanisms. RESULTS: The Fgf9S99N mutation in mice led to reduced ameloblasts, impaired enamel formation, and increased apoptosis in the cervical loop (CL). DESC sphere culture experiments revealed that FGF9 facilitated DESC survival via activating ERK/CREB signaling, without affecting cell proliferation. Furthermore, in vitro tissue culture experiments demonstrated that FGF9 promoted enamel formation in a manner dependent on the presence of mesenchyme. Interestingly, FGF9 stimulation inhibited enamel formation in isolated enamel epithelia and DESC spheres. Further investigation revealed that FGF9 supports DESC survival and promotes amelogenesis by stimulating the secretion of FGF3 and FGF10 in dental mesenchymal cells via the MAPK/ERK signaling pathway. CONCLUSIONS: Our study demonstrates that Fgf9 is essential for DESC survival and enamel formation. Fgf9 performs as a dual-directional regulator of the dental enamel epithelium, not only inhibiting DESC differentiation into ameloblasts to preserve the stemness of DESC, but also promoting ameloblast differentiation through epithelial-mesenchymal interactions.

First independent validation of the proton-boron capture therapy concept.

Boron has been suggested to enhance the biological effectiveness of proton beams in the Bragg peak region via the p + 11B → 3α nuclear capture reaction. However, a number of groups have observed no such enhancement in vitro or questioned its proposed mechanism recently. To help elucidate this phenomenon, we irradiated DU145 prostate cancer or U-87 MG glioblastoma cells by clinical 190 MeV proton beams in plateau or Bragg peak regions with or without 10B or 11B isotopes added as sodium mercaptododecaborate (BSH). The results demonstrate that 11B but not 10B or other components of the BSH molecule enhance cell killing by proton beams. The enhancement occurs selectively in the Bragg peak region, is present for boron concentrations as low as 40 ppm, and is not due to secondary neutrons. The enhancement is likely initiated by proton-boron capture reactions producing three alpha particles, which are rare events occurring in a few cells only, and their effects are amplified by intercellular communication to a population-level response. The observed up to 2-3-fold reductions in survival levels upon the presence of boron for the studied prostate cancer or glioblastoma cells suggest promising clinical applications for these tumour types.

An Optimized Peptide Antagonist of CXCR4 Limits Survival of BCR-ABL1-Transformed Cells in Philadelphia-Chromosome-Positive B-Cell Acute Lymphoblastic Leukemia.

Philadelphia-chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) is characterized by reciprocal chromosomal translocation between chromosome 9 and 22, leading to the expression of constitutively active oncogenic BCR-ABL1 fusion protein. CXC chemokine receptor 4 (CXCR4) is essential for the survival of BCR-ABL1-transformed mouse pre-B cells, as the deletion of CXCR4 induces death in these cells. To investigate whether CXCR4 inhibition also effectively blocks BCR-ABL1-transformed cell growth in vitro, in this study, we explored an array of peptide-based inhibitors of CXCR4. The inhibitors were optimized derivatives of EPI-X4, an endogenous peptide antagonist of CXCR4. We observed that among all the candidates, EPI-X4 JM#170 (referred to as JM#170) effectively induced cell death in BCR-ABL1-transformed mouse B cells but had little effect on untransformed wild-type B cells. Importantly, AMD3100, a small molecule inhibitor of CXCR4, did not show this effect. Treatment with JM#170 induced transient JNK phosphorylation in BCR-ABL1-transformed cells, which in turn activated the intrinsic apoptotic pathway by inducing cJun, Bim, and Bax gene expressions. Combinatorial treatment of JM#170 with ABL1 kinase inhibitor Imatinib exerted a stronger killing effect on BCR-ABL1-transformed cells even at a lower dose of Imatinib. Surprisingly, JM#170 actively killed Sup-B15 cells, a BCR-ABL1+ human ALL cell line, but had no effect on the BCR-ABL1- 697 cell line. This suggests that the inhibitory effect of JM#170 is specific for BCR-ABL1+ ALL. Taken together, JM#170 emerges as a potent novel drug against Ph+ ALL.

Cryopreservation of human teeth using vitrification method with cryoprotectant cocktails and N-acetylcysteine for banking and clinical applications.

Preserving freshly-extracted healthy human teeth offers an optional resource for potential tooth transplantation and cell therapy. This study aimed to assess the impact of vitrification, utilizing a blend of cryoprotectant agents and N-acetylcysteine (NAC), on the cryopreservation of periodontal ligament tissues, and investigate the underlying mechanisms of NAC on the tooth cryopreservation. Periodontal ligament cells were isolated from freshly-extracted healthy human permanent teeth, and cell sheets of PDLCs were fabricated. The samples including cell sheets, freshly-extracted human and rat teeth were cryopreserved with or without NAC for three months. The viability, ROS level, gene expressions and microstructure of PDLCs within cell sheets were assessed. The expression of SOD-2, Caspase3, LC3A/B and Catalase were evaluated through western blotting. Histological assessments of cryopreserved cell sheets and teeth were conducted. PDLCs were isolated from cryopreserved teeth, and their immunophenotype and differentiation ability were evaluated. The data was analyzed using one-way analysis of variance. The vitrification method showed good performance in preserving the viability and differentiation potential of PDLCs. Cryopreservation supplemented with NAC improved the survival rate of PDLCs, enhanced osteogenic differentiation ability, upregulated the expression of SOD-2 and Catalase, and inhibited cell apoptosis. Additionally, mRNA sequencing analysis revealed a significant activation of the PI3K-AKT pathway following cryopreservation via vitrification. Adding a PI3K-AKT activator improved the survival rates of PDLCs post-cryopreservation. The vitrification strategy combining various CPAs and NAC proved to be feasible for tooth cryopreservation. Targeting the PI3K-AKT pathway may improve the efficacy of tooth cryopreservation.

Transglutaminase 2 Regulates HSF1 Gene Expression in the Acute Phase of Fish Optic Nerve Regeneration.

Fish retinal ganglion cells (RGCs) can regenerate after optic nerve lesions (ONLs). We previously reported that heat shock factor 1 (HSF1) and Yamanaka factors increased in the zebrafish retina 0.5-24 h after ONLs, and they led to cell survival and the transformation of neuro-stem cells. We also showed that retinoic acid (RA) signaling and transglutaminase 2 (TG2) were activated in the fish retina, performing neurite outgrowth 5-30 days after ONLs. In this study, we found that RA signaling and TG2 increased within 0.5 h in the zebrafish retina after ONLs. We examined their interaction with the TG2-specific morpholino and inhibitor due to the significantly close initiation time of TG2 and HSF1. The inhibition of TG2 led to the complete suppression of HSF1 expression. Furthermore, the results of a ChIP assay with an anti-TG2 antibody evidenced significant anti-TG2 immunoprecipitation of HSF1 genome DNA after ONLs. The inhibition of TG2 also suppressed Yamanaka factors' gene expression. This rapid increase in TG2 expression occurred 30 min after the ONLs, and RA signaling occurred 15 min before this change. The present study demonstrates that TG2 regulates Yamanaka factors via HSF1 signals in the acute phase of fish optic nerve regeneration.

51Cr Red Blood Cells in the Study of Hematologic Disease: A Historical Review.

The early years of nuclear medicine included the development and clinical use of several in vitro or nonimaging procedures. The use of radionuclides as replacements for nonradioactive dyes brought improved accuracies and less subjective measurements to indicator dilution studies of body compartments such as the gastrointestinal system, lungs, urinary system, and vascular space. A popular nuclear medicine procedure was the radionuclide dilution method for quantitation of whole-blood volume or red blood cell volume or mass using 51Cr-labeled red blood cells-an important diagnostic element in patients suspected of having polycythemia vera, congestive heart failure, hypertension, shock, syncope, and other abnormal blood volume disorders. The radionuclide dilution method led to improved evaluation of red blood cell survival, which is important for clinical treatment planning in anemia and confirmation of splenic sequestration of damaged red blood cells. Although it was discovered that 51Cr was a chemically stable radiolabel of red blood cells after binding to intracellular hemoglobin, few nuclear medicine departments offered the clinical study for referring physicians because it required laboratory expertise for technologists, patient coordination, and a time-consuming procedure. The introduction of improved methods that are less time-consuming and have clinically acceptable results, along with the discontinuation of the sodium chromate 51Cr injection radiopharmaceutical by manufacturers, has consigned 51Cr red blood cells for red blood cell volume, mass, or survival evaluation to the list of retired nuclear medicine studies.

Isolation and Culture of Adult Rat Dorsal Root Ganglion Neurons for the In Vitro Analysis of Peripheral Nerve Degeneration and Regeneration.

Isolation and culture of dorsal root ganglion (DRG) neurons from adult animals is a useful experimental system for evaluating neural plasticity after axonal injury, as well as the neurological dysfunction resulting from aging and various types of disease. In this chapter, we will introduce a detailed method for the culture of mature rat DRG neurons. About 30-40 ganglia are dissected from a rat and mechanically and enzymatically digested. Subsequently, density gradient centrifugation of the digested tissue using 30% Percoll efficiently eliminates myelin debris and non-neuronal cells, to afford neuronal cells with a high yield and purity.

The effect of hydrogen peroxide and subsequent resveratrol application to CAD-CAM blocks on the cell viability of fibroblasts.

The aim is to assess viability of fibroblasts exposed to 2 CAD-CAM blocks and a nanohybrid resin after application of hydrogen peroxide (HP) and resveratrol with 2 extraction media at 24 h, 48 h, and 72 h. Eighteen specimens were obtained from Lava Ultimate (LU), Vita Enamic (VE), and Grandio (GR). Specimens of each material were divided into 3 groups (material only, bleached, resveratrol applied) for 2 extraction media as artificial saliva (AS) and phosphate buffer saline (PBS) (n = 3). For bleached group, 40% HP was applied to specimens for 20 min twice. For resveratrol group, 0.5 µM resveratrol was applied after bleaching for 10 min. Mouse fibroblast cells were exposed to extracts of each group. The viability of cells was determined with MTT assay at 24 h, 48 h, and 72 h. Cell viability data (%) were analyzed statistically using one-way ANOVA, and post hoc Tukey test. Bleached materials showed the lowest cell viability (PBS; p < 0.01/ AS; p < 0.001). There is no statistically significant difference between resveratrol applied and bleached groups (PBS; p = 0.14/ AS; p = 0.072). Regardless of period of time and procedure, GR showed lower viable cell numbers than LU and VE (p < 0.001). Viable cell numbers were higher at 24 h than at 72 h (p < 0.001). There was no statistically difference between AS and PBS (p > 0.05). For all materials, the application of resveratrol did not affect the cell viability which decreased after bleaching over time. The decrease in nanohybrid resin was more critical than hybrid CAD-CAM blocks. The type of extraction media had no effect on cell viability results.

Focal adhesion kinase signaling - tumor vulnerabilities and clinical opportunities.

Focal adhesion kinase (FAK; encoded by PTK2) was discovered over 30 years ago as a cytoplasmic protein tyrosine kinase that is localized to cell adhesion sites, where it is activated by integrin receptor binding to extracellular matrix proteins. FAK is ubiquitously expressed and functions as a signaling scaffold for a variety of proteins at adhesions and in the cell cytoplasm, and with transcription factors in the nucleus. FAK expression and intrinsic activity are essential for mouse development, with molecular connections to cell motility, cell survival and gene expression. Notably, elevated FAK tyrosine phosphorylation is common in tumors, including pancreatic and ovarian cancers, where it is associated with decreased survival. Small molecule and orally available FAK inhibitors show on-target inhibition in tumor and stromal cells with effects on chemotherapy resistance, stromal fibrosis and tumor microenvironment immune function. Herein, we discuss recent insights regarding mechanisms of FAK activation and signaling, its roles as a cytoplasmic and nuclear scaffold, and the tumor-intrinsic and -extrinsic effects of FAK inhibitors. We also discuss results from ongoing and advanced clinical trials targeting FAK in low- and high-grade serous ovarian cancers, where FAK acts as a master regulator of drug resistance. Although FAK is not known to be mutationally activated, preventing FAK activity has revealed multiple tumor vulnerabilities that support expanding clinical combinatorial targeting possibilities.

Biological resilience in health and disease.

All living organisms - from single-celled prokaryotes through to invertebrates and humans - are frequently exposed to numerous challenges during their lifetime, which could damage their molecular and cellular contents and threaten their survival. Nevertheless, these diverse organisms are, on the whole, remarkably resilient to potential threats. Recent years have seen rapid advances in our mechanistic understanding of this emerging phenomenon of biological resilience, which enables cells, tissues and whole organisms to bounce back from challenges or stress. In this At a Glance article, I discuss current knowledge on the diverse molecular mechanisms driving biological resilience across scales, with particular focus on its dynamic and adaptive nature. I highlight emerging evidence that loss of biological resilience could underly numerous pathologies, including age-related frailty and degenerative disease. Finally, I present the multi-disciplinary experimental approaches that are helping to unravel the causal mechanisms of resilience and how this emerging knowledge could be harnessed therapeutically in the clinic.

Alpha-synuclein shapes monocyte and macrophage cell biology and functions by bridging alterations of autophagy and inflammatory pathways.

Introduction: Abnormal spreading of alpha-synuclein (αS), a hallmark of Parkinson's disease, is known to promote peripheral inflammation, which occurs in part via functional alterations in monocytes/macrophages. However, underlying intracellular mechanisms remain unclear. Methods: Herein we investigate the subcellular, molecular, and functional effects of excess αS in human THP-1 monocytic cell line, THP-1-derived macrophages, and at least preliminarily, in primary monocyte-derived macrophages (MDMs). In cells cultured w/wo recombinant αS (1 µM) for 4 h and 24 h, by Confocal microscopy, Western Blot, RT-qPCR, Elisa, and Flow Cytometry we assessed: i) αS internalization; ii) cytokine/chemokine expression/secretion, and C-C motif chemokine receptor 2 (CCR2) levels; iii) autophagy (LC3II/I, LAMP1/LysoTracker, p62, pS6/total S6); and iv) lipid droplets (LDs) accumulation, and cholesterol pathway gene expression. Transwell migration assay was employed to measure THP-1 cell migration/chemotaxis, while FITC-IgG-bead assay was used to analyze phagocytic capacity, and the fate of phagocytosed cargo in THP-1-derived macrophages. Results: Extracellular αS was internalized by THP-1 cells, THP-1-derived macrophages, and MDMs. In THP1 cells, αS induced a general pro-inflammatory profile and conditioned media from αS-exposed THP-1 cells potently attracted unstimulated cells. However, CCL2 secretion peaked at 4 h αS, consistent with early internalization of its receptor CCR2, while this was blunted at 24 h αS exposure, when CCR2 recycled back to the plasma membrane. Again, 4 h αS-exposed THP-1 cells showed increased spontaneous migration, while 24 h αS-exposed cells showed reduced chemotaxis. This occurred in the absence of cell toxicity and was associated with upregulation of autophagy/lysosomal markers, suggesting a pro-survival/tolerance mechanism against stress-related inflammation. Instead, in THP-1-derived macrophages, αS time-dependently potentiated the intracellular accumulation, and release of pro-inflammatory mediators. This was accompanied by mild toxicity, reduced autophagy-lysosomal markers, defective LDs formation, as well as impaired phagocytosis, and the appearance of stagnant lysosomes engulfed with phagocytosed cargo, suggesting a status of macrophage exhaustion reminiscent of hypophagia. Discussion: In summary, despite an apparently similar pro-inflammatory phenotype, monocytes and macrophages respond differently to intracellular αS accumulation in terms of cell survival, metabolism, and functions. Our results suggest that in periphery, αS exerts cell- and context-specific biological effects bridging alterations of autophagy, lipid dynamics, and inflammatory pathways.

Priming mesenchymal stem cells to develop "super stem cells".

The stem cell pre-treatment approaches at cellular and sub-cellular levels encompass physical manipulation of stem cells to growth factor treatment, genetic manipulation, and chemical and pharmacological treatment, each strategy having advantages and limitations. Most of these pre-treatment protocols are non-combinative. This editorial is a continuum of Li et al's published article and Wan et al's editorial focusing on the significance of pre-treatment strategies to enhance their stemness, immunoregulatory, and immunosuppressive properties. They have elaborated on the intricacies of the combinative pre-treatment protocol using pro-inflammatory cytokines and hypoxia. Applying a well-defined multi-pronged combinatorial strategy of mesenchymal stem cells (MSCs), pre-treatment based on the mechanistic understanding is expected to develop "Super MSCs", which will create a transformative shift in MSC-based therapies in clinical settings, potentially revolutionizing the field. Once optimized, the standardized protocols may be used with slight modifications to pre-treat different stem cells to develop "super stem cells" with augmented stemness, functionality, and reparability for diverse clinical applications with better outcomes.

Detection and clinical application of red blood cell survival. / çº¢ç»†èƒžå¯¿å‘½çš„æ£€æµ‹åŠå ¶ä¸´åºŠåº”ç”¨.

There are 2 techniques for detecting red blood cell survival (RBCS) detection techniques: red blood cell labeling test and carbon monoxide (CO) breath test. The former has disadvantages such as long measurement times and complicated procedures, while the latter is simple, convenient, moderately priced, and capable of dynamically monitoring changes in RBCS before and after treatment. Currently, the CO breath test is gradually being implemented in clinical practice. RBCS is not only applied to hematologic diseases such as multiple myeloma, myelodysplastic syndromes, lymphoma, and thalassemia, but also to non-hematologic diseases like type 2 diabetes and chronic kidney disease. It can assist in diagnosis, guide treatment, evaluate drug treatment efficacy, and predict disease progression.