Cell fate following irradiation of MDA-MB-231 and MCF-7 breast cancer cells pre-exposed to the setrahydroisoquinoline sulfamate microtubule disruptor STX3451

The compound STX3451 is not commercially available.SUPPLEMENTARY MATERIAL : TABLE S1: Data analysis comparing flow cytometric quantification of individual cell cycle phases across 24-h and 48-h timelines. TABLE S2: Data analysis of flow cytometric quantification of the cell cycle distribution in MCF-7 cells exposed to STX3451 and radiation. TABLE S3: Statistical analysis of cell cycle distribution in MCF-7 cells exposed to STX3451 and radiation. TABLE S4: Data analysis comparing flow cytometric quantification of individual cell cycle phases across 24-h and 48-h timelines in MDA-MB-231 cells. TABLE S5: Statistical analysis of cell cycle progression in MDA-MB-231 cells exposed to STX3451 and radiation. TABLE S6: Statistical analysis of cell cycle distribution in MDA-MB-231 cells exposed to STX3451 and radiation. TABLE S7: Annexin-V analysis of MCF-7 cells 48-h. TABLE S8: Annexin-V statistical analysis of MDA-MB-231 48-h. TABLE S9: Colony formation in MCF-7 cells. TABLE S10: Colony formation in MDA-MB-231 cells. TABLE S11: The total number of Mn in MCF-7 cells that were terminated 2- and 24-h after radiation. TABLE S12: The total number of Mn in MDA-MB-231 cells terminated 2- and 24-h after radiation. TABLE S13: Number of Mn per cell in MCF-7 cells terminated 2-h after radiation. TABLE S14: Number of Mn per cell in MCF-7 cells terminated 24-h after radiation. TABLE S15: Number of Mn per cell in MDA-MB-231 cells terminated 2-h after radiation. TABLE S16: The number of Mn per cell in MDA-MB-231 cells that were terminated 24-h after radiation. TABLE S17: Superoxide detection in MCF-7 cells treated with the various modalities. TABLE S18: Superoxide detection in pre-sensitized MDA-MB-231 cells. TABLE S19: Statistical analysis of ATM expression in combination treated MCF-7 and MDA-MB-231 cells 2- and 24-h post-radiation. TABLE S20: Nontumored animal toxicity assay; VIDEO S1: not applicable.Atetrahydroisoquinoline (THIQ) core is able tomimic theAand B rings of 2-methoxyestradiol (2ME2), an endogenous estrogen metabolite that demonstrates promising anticancer properties primarily by disrupting microtubule dynamic instability parameters, but has very poor pharmaceutical properties that can be improved by sulfamoylation. The non-steroidal THIQ-based microtubule disruptor 2-(3-bromo-4,5-dimethoxybenzyl)-7-methoxy-6-sulfamoyloxy-1,2,3,4-tetrahydroisoquinoline (STX3451), with enhanced pharmacokinetic and pharmacodynamic profiles, was explored for the first time in radiation biology. We investigated whether 24 h pre-treatment with STX3451 could pre-sensitize MCF-7 and MDA-MB-231 breast cancer cells to radiation. This regimen showed a clear increase in cytotoxicity compared to the individual modalities, results that were contiguous in spectrophotometric analysis, flow cytometric quantification of apoptosis induction, clonogenic studies and microscopy techniques. Drug pre-treatment increased radiation-induced DNA damage, with statistically more double-strand (ds) DNA breaks demonstrated. The latter could be due to the induction of a radiation-sensitive metaphase block or the increased levels of reactive oxygen species, both evident after compound exposure. STX3451 pre-exposure may also delay DNA repair mechanisms, as the DNA damage response element ataxia telangiectasia mutated (ATM) was depressed. These in vitro findings may translate into in vivo models, with the ultimate aim of reducing both radiation and drug doses for maximal clinical effect with minimal adverse effects.The Research Committee of the University of Pretoria, the Struwig-Germeshuysen Trust, the Cancer Association of South Africa (CANSA), the National Research Foundation (NRF) and the Research Development Programme of the University of Pretoria (RDP-UP).https://www.mdpi.com/journal/moleculesam2023Physiolog

The BLAST Survey of the Vela Molecular Cloud: Physical Properties of the Dense Cores in Vela-D

The Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) carried out a 250, 350 and 500 micron survey of the galactic plane encompassing the Vela Molecular Ridge, with the primary goal of identifying the coldest dense cores possibly associated with the earliest stages of star formation. Here we present the results from observations of the Vela-D region, covering about 4 square degrees, in which we find 141 BLAST cores. We exploit existing data taken with the Spitzer MIPS, IRAC and SEST-SIMBA instruments to constrain their (single-temperature) spectral energy distributions, assuming a dust emissivity index beta = 2.0. This combination of data allows us to determine the temperature, luminosity and mass of each BLAST core, and also enables us to separate starless from proto-stellar sources. We also analyze the effects that the uncertainties on the derived physical parameters of the individual sources have on the overall physical properties of starless and proto-stellar cores, and we find that there appear to be a smooth transition from the pre- to the proto-stellar phase. In particular, for proto-stellar cores we find a correlation between the MIPS24 flux, associated with the central protostar, and the temperature of the dust envelope. We also find that the core mass function of the Vela-D cores has a slope consistent with other similar (sub)millimeter surveys.Comment: Accepted for publication in the Astrophysical Journal. Data and maps are available at http://blastexperiment.info

Molecular insights into an ancient form of Paget’s disease of bone

Paget’s disease of bone (PDB) is a chronic skeletal disorder that can affect one or several bones in individuals over 55 years of age. PDB like changes have been reported in archaeological remains as old as Roman, although accurate diagnosis and natural history of the disease is lacking. Six skeletons from a collection of 130 excavated at Norton Priory in the North West of England, which dates to medieval times, show atypical and extensive pathological changes resembling contemporary PDB affecting up to 75% of individual skeletons. Disease prevalence in the remaining collection is high, at least 16% of adults, with age at death estimations as low as 35 years. Despite these atypical features, paleoproteomic analysis identified sequestosome 1 (SQSTM1) or p62, a protein central to the pathological milieu of PDB, as one of the few non69 collagenous human sequences preserved in skeletal samples. Targeted proteomic analysis detected >60% of the ancient p62 primary sequence with western blotting indicating p62 abnormalities including in dentition. Direct sequencing of ancient DNA excluded contemporary PDB associated SQSTM1 mutations. Our observations indicate that the ancient p62 protein is likely modified within its C-terminal ubiquitin associated (UBA) domain. Ancient microRNAs were remarkably preserved in an osteosarcoma from a skeleton with extensive disease, with miR-16 expression consistent with that reported in contemporary PDB associated bone tumours. Our work displays the use of proteomics to inform diagnosis of ancient disease such as atypical PDB, which has unusual features presumably potentiated by as yet unidentified environmental or genetic factors

Cell fate following radiation of MDA-MB-231 and MCF-7 breast cancer cells pre-exposed to a tetrahydroisoquinoline analogue

Chemotherapy and radiation, together with surgery, remain the mainstays of cancer therapeutics. There remains a need to identify agents which circumvent multidrug resistance, radioresistance and minimise the side effect profile of the treatment modalities. To increase the efficacy of 2-Methoxyestradiol (2ME2) as an anticancer agent, a sulfamoylated analogue was designed to retain the functional groups of the parent compound presented on a non-steroidal scaffold. A tetrahydroisoquinoline (THIQ) core was used to mimic the A- and B rings of 2ME2. In this study, 2-(3-Bromo-4,5-dimethoxybenzyl)-7-methoxy-6-sulfamoyloxy-1,2,3,4-tetrahydroisoquinoline (STX3451) was used to pre-treat MDA-MB-231- and MCF-7 breast cancer cells before radiation in order to investigate the cell fate as a result of this combination treatment. The concentration at which growth cell proliferation was inhibited by 50% (GI50) was determined via spectrophotometric analysis of crystal violet (CV) staining. Thereafter, cells were exposed to 0.07 μM STX3451 for 24-hours prior to a single dose of 6 Gray (Gy) radiation. In order to determine the temporal intracellular events in response to the combination parallel to the individual treatment controls, experiments were terminated 2-, 24-, or 48-hours after radiation. Cell cycle progression and induction of apoptosis were investigated via flow cytometric analysis. Morphological changes were investigated using light microscopy. The extent of radiation-induced deoxyribonucleic acid (DNA) damage was assessed via micronuclei (Mn) quantification. Early in vitro response to the combination therapy included quantification of reactive oxygen species (ROS) generation using flow cytometric analysis of hydroethidine (HE) staining. DNA-damage repair signalling as a response to the treatments was investigated by semi-quantitative analysis of ataxia-telangiectasia mutated (ATM) expression using Western blots. Long-term cellular survival was assessed via clonogenic studies. Cytotoxicity studies on both cell lines revealed half maximum growth inhibitory concentration (GI50) values in the micromolar range. MCF-7 and MDA-MB-231 cells displayed a metaphase block, with a concurrent decrease in viability and an increase in apoptosis in response to the iv combination treatment, a phenomenon that was attributed to the STX3451 pre-treatment and the radiation. On microscopy, an increased number of rounded cells were observed in response to combination treatment. Both cell lines displayed significantly more Mn formation in response to the combination treatment when compared to the experimental controls. MCF-7 cells exposed to the combination treatment resulted in significantly more ROS generation 48-hours after radiation, in alignment with the drug control. ATM expression was suppressed in response to the combination-and compound-only treated MDA-MB-231- and MCF-7 cells, which indicates possible suppression of the DNA damage response (DDR). Both MCF-7 and MDA-MB-231 cells displayed a significant decrease in long-term cell survival in response to combination treatment when compared to experimental controls. In conclusion, STX3451 demonstrated potential radiosensitizing effects in breast cancer cells. By increasing DNA damage, inhibiting expression of the essential DNA damage repair protein ATM, and decreasing the long-term viability of breast cancer cells, this combination treatment shows promise in reducing the amount of radiation required to treat breast cancer. Future studies should involve senescence-associated β-galactosidase detection to determine whether these cells undergo senescence in response to STX3451 and radiation combination treatment.Dissertation (MSc (Human Physiology))--University of Pretoria, 2021.PhysiologyMSc (Human Physiology)Unrestricte

Automation and artificial intelligence in radiation therapy treatment planning

Automation and artificial intelligence (AI) is already possible for many radiation therapy planning and treatment processes with the aim of improving workflows and increasing efficiency in radiation oncology departments. Currently, AI technology is advancing at an exponential rate, as are its applications in radiation oncology. This commentary highlights the way AI has begun to impact radiation therapy treatment planning and looks ahead to potential future developments in this space. Historically, radiation therapist's (RT's) role has evolved alongside the adoption of new technology. In Australia, RTs have key clinical roles in both planning and treatment delivery and have been integral in the implementation of automated solutions for both areas. They will need to continue to be informed, to adapt and to transform with AI technologies implemented into clinical practice in radiation oncology departments. RTs will play an important role in how AI-based automation is implemented into practice in Australia, ensuring its application can truly enable personalised and higher-quality treatment for patients. To inform and optimise utilisation of AI, research should not only focus on clinical outcomes but also AI's impact on professional roles, responsibilities and service delivery. Increased efficiencies in the radiation therapy workflow and workforce need to maintain safe improvements in practice and should not come at the cost of creativity, innovation, oversight and safety.</p

The balloon-borne large aperture sub-millimeter telescope

The balloon-borne large aperture sub-millimeter telescope (BLAST) is a new instrument to study galaxies at high redshift and to help answer questions about our galaxy and star formation. BLAST will fly from a long duration balloon. The telescope design incorporates a 2-m primary mirror with large-format bolometer arrays operating at 250, 350 and 500 μm with 149, 88 and 43 detectors, respectively. By providing the first sensitive large-area (10 deg2) sub-mm surveys at these wavelengths, BLAST will address some of the most important galactic and cosmological questions regarding the formation and evolution of stars, galaxies and clusters. Galactic and extragalactic BLAST surveys will do the following: (i) identify large numbers of high-redshift galaxies; (ii) measure photometric redshifts, rest-frame far-infrared luminosities and star formation rates thereby constraining the evolutionary history of the galaxies that produce the far-infrared and sub-mm background; (iii) measure cold pre-stellar sources associated with the earliest stages of star and planet formation; (iv) make high-resolution maps of diffuse galactic emission over a wide range of galactic latitudes. The BLAST long duration balloon experiment will also provide catalogues of 3000–5000 extragalactic sub-mm sources and a 100 deg2 sub-mm galactic plane survey which will serve as a legacy to be followed at other wavelengths and resolutions, including sub-arcsecond imaging with the Atacama Large Millimeter Array

BLAST: Balloon-Borne Large Aperture Submillimeter Telescope

BLAST is the Balloon-borne Large-Aperture Sub-millimeter Telescope. It will fly from a Long Duration Balloon (LDB) platform from Antarctica. The telescope design incorporates a 2 m primary mirror with large-format bolometer arrays operating at 250, 350 and 500 microns. By providing the first sensitive large-area (10 sq. deg.) sub-mm surveys at these wavelengths, BLAST will address some of the most important galactic and cosmological questions regarding the formation and evolution of stars, galaxies and clusters. Galactic and extragalactic BLAST surveys will: (i) identify large numbers of high-redshift galaxies; (ii) measure photometric redshifts, rest-frame FIR luminosities and star formation rates thereby constraining the evolutionary history of the galaxies that produce the FIR and sub-mm background; (iii) measure cold pre-stellar sources associated with the earliest stages of star and planet formation; (iv) make high-resolution maps of diffuse galactic emission over a wide range of galactic latitudes. In addition to achieving the above scientific goals, the exciting legacy of the BLAST LDB experiment will be a catalogue of 3000-5000 extragalactic sub-mm sources and a 100 sq. deg. sub-mm galactic plane survey. Multi-frequency follow-up observations from SIRTF, ASTRO-F, and Herschel, together with spectroscopic observations and sub-arcsecond imaging from ALMA are essential to understand the physical nature of the BLAST sources

BLAST - A New Balloon-Borne Submillimeter Telescope

BLAST the Balloon-borne Large Aperture Sub-millimeter Telescope, will have three bolometer arrays operating at 250, 350, and 500 pm, with 149, 88, and 43 detectoi-s respectively. The arrays will be cooled to 300 rnK so that the receiver's noise (NEFD) will be dominated by photon shot noise and atmospheric emission. Because of the high (35 km) altitude of balloon observations, atmospheric noise will be low and we expect NEFDs less than 241 mJy/H:1 2 in all channels. A 2.0 m diameter spherical mirror will give diffraction limited resolutions of 30, 41, and 59" respectively. The first test flight, planned for early 2003, will last 6-24 hours across North America. Long-duration balloon flights from Antarctica will begin in late 2003 and will last 14 days. BLAST will yield data on astronomical problems as close as nearby stars and as far away as the beginnings of the Universe

Extragalactic Submillimetric Surveys with BLAST

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has recently conducted an extragalactic submillimetric survey of the Chandra Deep Field South region of unprecedented size, depth, and angular resolution in three wavebands centered at 250, 350, and 500 µm. BLAST wavelengths are chosen to study the Cosmic Infrared Background near its peak at 200 µm. We find that most of the CIB at these wavelengths is contributed by galaxies detected at 24 µm by the MIPS instrument on Spitzer, and that the source counts distribution shows a population with strongly evolving density and luminosity. These results anticipate what can be expected from the surveys that will be conducted with the SPIRE instrument on the Herschel space observatory