<p>This study investigated the long-term stability of cytogenetic and morphological markers, including dicentric chromosomes (DC), unbalanced translocation (UT), balanced translocation (BT), and Pseudo Pelger-Huët Anomaly (PPHA), in a radiation worker exposed to an acute dose of 60Co-γ radiation. Initial dose assessment, one week after exposure via Thermoluminescent dosimeters (TLDs) and DC, yielded a physical dose of 438.8 mGy and a biological dose of 398 mGy respectively. A follow-up biodosimetry evaluation, conducted 24 years postexposure, yielded a dose estimate of 449 mGy on the basis of BT, closely matching the initial TLD measurement (+ 2.3% relative error). In contrast, the DC, UT, and micronuclei (MN) frequencies fell within the background range, confirming their instability over time. We also assessed the presence of PPHA in blood smears from the same volunteer. PPHA, a morphological marker of neutrophils originating exclusively in vivo from bone marrow progenitor cells, demonstrated a more than twofold increase in frequency compared to background levels, suggesting an association with radiation exposure. This is the first report of concurrent BT and PPHA persistence in the same individual, demonstrating the suitability of these biomarkers for retrospective detection of past radiation exposure. BT offered reliable dose reconstruction decades after exposure. We could not translate the PPHA yield into an absorbed dose, as no in-house dose‒response curve was established.No abstract available.</p>

Digital object identifier (DOI): 10.1038/s41598-025-14858-4

<p><strong>Background: </strong>Acute myeloid leukemia (AML) is a complicated disease with uncontrolled hematopoietic precursor proliferation induced by various genetic alterations. Runt-related transcription factor-1 (<em>RUNX1</em>) is commonly disrupted by chromosomal translocations in hematological malignancies.</p> <p><strong>Aim: </strong>To characterize <em>RUNX1</em> gene rearrangements and copy number variations in newly diagnosed adult AML patients, with an emphasis on the impact of clinical and laboratory features on the outcome.</p> <p><strong>Methods: </strong>Fluorescence in situ hybridization was used to test <em>RUNX1</em> gene alterations in 77 newly diagnosed adult AML cases. <em>NPM1</em>, <em>FLT3/ITD</em>, <em>FLT3/TKD</em>, and <em>KIT</em> mutations were tested by PCR. Prognostic clinical and laboratory findings were studied in relation to <em>RUNX1</em> alterations.</p> <p><strong>Results: </strong><em>RUNX1</em> abnormalities were detected by fluorescence in situ hybridization in 41.6% of patients: 20.8% had translocations, 22.1% had amplification, and 5.2% had deletion. Translocations prevailed in AML-M2 (<em>P</em> = 0.019) with a positive expression of myeloperoxidase (<em>P</em> = 0.031), whereas deletions dominated in M4 and M5 subtypes (<em>P</em> = 0.008) with a positive association with CD64 expression (<em>P</em> = 0.05). The modal chromosomal number was higher in cases having amplifications (<em>P</em> = 0.007) and lower in those with deletions (<em>P</em> = 0.008). <em>RUNX1</em> abnormalities were associated with complex karyotypes (<em>P</em> &lt; 0.001) and were mutually exclusive of <em>NPM1</em> mutations. After 44 months of follow-up, <em>RUNX1</em> abnormalities affected neither patients' response to treatment nor overall survival.</p> <p><strong>Conclusion: </strong><em>RUNX1</em> abnormalities were mutually exclusive of <em>NPM1</em> mutations. <em>RUNX1</em> abnormalities affected neither patients' response to treatment nor overall survival.</p>

The Emergence of Artificial Intelligence-Guided Karyotyping: A Review and Reflection.

<p>Artificial intelligence (AI) has entered the medical subspecialty of cytogenetics with the recent introduction of AI-guided karyotyping into the clinical laboratory. Karyotyping is an essential component of the cytogenetic analysis process; however, it is both labor-intensive and time-consuming. The introduction of AI algorithms into karyotyping software streamlines this process to provide accurate and abundant auto-karyotyped images for laboratory professionals to review and, also, alters the paradigm for chromosome analysis. Herein, we provide an overview of the AI-guided karyotyping products currently available for clinical use, discuss their utilization in the cytogenetics laboratory, and highlight changes AI-guided karyotyping has brought for early users. Finally, we reflect on our own laboratory observations and experience to discuss issues and practices that may need to adapt to best utilize this promising new technology.</p>

Digital object identifier (DOI): 10.3390/genes16060685

Successful pregnancy after preimplantation genetic testing for structural rearrangements in a couple with complex chromosome rearrangement and recurrent in vitro fertilization failures: a case report.

To present a case of a couple with 20 years of infertility and 10 recurrent in\u160?vitro fertilization (IVF) failures, identifying a paternal complex chromosome rearrangement using high-resolution karyotype together with preimplantation genetic testing for structural rearrangements (PGT-SR) and utilizing IVF-intracytoplasmic sperm injection to achieve a successful pregnancy. Case report. Al Ain Fertility Center, Abu Dhabi, United Arab Emirates. A 40-year-old male patient and a 37-year-old female patient with a history of infertility and recurrent IVF failures. In\u160?vitro fertilization-intracytoplasmic sperm injection with high-resolution karyotype and PGT-SR. Identification of chromosomal abnormalities, successful embryo development, pregnancy outcome, and newborn karyotyping. Karyotyping revealed a paternal complex chromosome rearrangement, t(3;4;12) (q21;q33;q21), and a chromosomal polymorphism in the female (1qh+). In\u160?vitro fertilization-intracytoplasmic sperm injection with PGT-SR produced one euploid/balanced female embryo from 20 embryos across 8 cycles. The patient conceived after hormone replacement therapy and frozen embryo transfer, resulting in an uneventful, full-term pregnancy and delivery of a healthy baby via C-section. Newborn karyotyping was normal (46,XX). High-resolution karyotype and PGT-SR should be offered to patients undergoing IVF, especially those with severe male factors, recurrent IVF failures, implantation failures, or recurrent pregnancy losses, to enhance the chances of a successful pregnancy.

Digital object identifier (DOI): 10.1016/j.xfre.2024.10.006

Spatial transcriptomics profiling of gallbladder adenocarcinoma: a detailed two-case study of progression from precursor lesions to cancer.

Most studies on tumour progression from precursor lesion toward gallbladder adenocarcinoma investigate lesions sampled from distinct patients, providing an overarching view of pathogenic cascades. Whether this reflects the tumourigenic process in individual patients remains insufficiently explored. Genomic and epigenomic studies suggest that a subset of gallbladder cancers originate from biliary intraepithelial neoplasia (BilIN) precursor lesions, whereas others form independently from BilINs. Spatial transcriptomic data supporting these conclusions are missing. Moreover, multiple areas with precursor or adenocarcinoma lesions can be detected within the same pathological sample. Yet, knowledge about intra-patient variability of such lesions is lacking. To characterise the spatial transcriptomics of gallbladder cancer tumourigenesis in individual patients, we selected two patients with distinct cancer aetiology and whose samples simultaneously displayed multiple areas of normal epithelium, BilINs and adenocarcinoma. Using GeoMx digital spatial profiling, we characterised the whole transcriptome of a high number of regions of interest (ROIs) per sample in the two patients (24 and 32 ROIs respectively), with each ROI covering approximately 200 cells of normal epithelium, low-grade BilIN, high-grade BilIN or adenocarcinoma. Human gallbladder organoids and cell line-derived tumours were used to investigate the tumour-promoting role of genes. Spatial transcriptomics revealed that each type of lesion displayed limited intra-patient transcriptomic variability. Our data further suggest that adenocarcinoma derived from high-grade BilIN in one patient and from low-grade BilIN in the other patient, with co-existing high-grade BilIN evolving via a distinct process in the latter case. The two patients displayed distinct sequences of signalling pathway activation during tumour progression, but Semaphorin 4\u160?A (SEMA4A) expression was repressed in both patients. Using human gallbladder-derived organoids and cell line-derived tumours, we provide evidence that repression of SEMA4A promotes pseudostratification of the epithelium and enhances cell migration and survival. Gallbladder adenocarcinoma can develop according to patient-specific processes, and limited intra-patient variability of precursor and cancer lesions was noticed. Our data suggest that repression of SEMA4A can promote tumour progression. They also highlight the need to gain gene expression data in addition to histological information to avoid understimating the risk of low-grade preneoplastic lesions.

Digital object identifier (DOI): 10.1186/s12885-024-12770-0

Proximal 4p Deletion Syndrome in an Infant With Multiple Systemic Anomalies.

Contiguous gene deletion in the short arm of chromosome 4 is linked to various neurodevelopmental disorders. In this study, we conducted peripheral blood chromosome G-banding karyotyping and whole-exome sequencing (WES) on a proband presenting with anal atresia, global developmental delay, lymphocytosis, and other multisystem anomalies. Additionally, chromosome G-banding karyotyping was also carried out on the proband's parents and brother. The 7-month-old proband was found to have a 26.738\u8201?Mb 4p15.33-p14 deletion as identified by chromosome G-banding karyotyping and WES. We identified a patient with proximal 4p deletion syndrome by karyotype and WES analysis, which might explain some of his phenotypes. Our research enhances clinicians' knowledge of this rare condition, and offers valuable genetic counseling to the affected family. Further research is necessary to identify the causative gene or critical region associated with proximal 4p deletion syndrome.

Digital object identifier (DOI): 10.1002/mgg3.70005

CNV Analysis through Exome Sequencing Reveals a Large Duplication Involved in Sex Reversal, Neurodevelopmental Delay, Epilepsy and Optic Atrophy.

<p>Duplications on the short arm of chromosome X, including the gene NR0B1 , have been associated with gonadal dysgenesis and with male to female sex reversal. Additional clinical manifestations can be observed in the affected patients, depending on the duplicated genomic region. Here we report one of the largest duplications on chromosome X, in a Lebanese patient, and we provide the first comprehensive review of duplications in this genomic region. A 2-year-old female patient born to non-consanguineous Lebanese parents, with a family history of one miscarriage, is included in this study. The patient presents with sex reversal, dysmorphic features, optic atrophy, epilepsy, psychomotor and neurodevelopmental delay. Single nucleotide variants and copy number variants analysis were carried out on the patient through exome sequencing (ES). This showed an increased coverage of a genomic region of around 23.6 Mb on chromosome Xp22.31-p21.2 (g.7137718-30739112) in the patient, suggestive of a large duplication encompassing more than 60 genes, including the NR0B1 gene involved in sex reversal. A karyotype analysis confirmed sex reversal in the proband presenting with the duplication, and revealed a balanced translocation between the short arms of chromosomes X and 14:46, X, t(X;14) (p11;p11) in her/his mother. This case highlights the added value of CNV analysis from ES data in the genetic diagnosis of patients. It also underscores the challenges encountered in announcing unsolicited incidental findings to the family.</p>

Digital object identifier (DOI): 10.3390/genes15070901

Cohesin RAD21 Gene Promoter Methylation in Patients with Acute Myeloid Leukemia.

<p>Aberrant gene promoter methylation is one of the hallmarks of Acute Myeloid Leukemia (AML). RAD21 is an important gene, implicated in sister chromatids cohesion, DNA repair, the regulation of gene transcription, apoptosis and hematopoiesis. In this study, we investigate the possible implication of RAD21 promoter methylation in AML pathogenesis using a cohort of AML patients and a cohort of healthy individuals. RAD21 promoter methylation was found in 24% of patients and in none of the controls ( p = 0.023), indicating a possible contribution to AML development. Interestingly, a statistically higher frequency of RAD21 methylation was observed in patients with trisomy 8 (9/21, 42.9%, p = 0.021), while none of the patients with aberrations of chromosome 11 had RAD21 gene promoter methylation (0%, 0/11, p = 0.048). Patients with monosomal and complex karyotypes showed low frequencies of RAD21 methylation (7.7% and 15.4%, respectively) without reaching statistical significance. Moreover, ASXL1 mutations were not found to be associated with RAD21 methylation. This is the first study which provides evidence for a possible pathogenetic role of RAD21 promoter methylation in AML development and especially in AML with trisomy 8. Further studies of RAD21 promoter methylation in large series of different AML genetic subgroups may contribute to the elucidation of AML pathogenesis and to the identification of new epigenetic biomarkers with diagnostic and prognostic value.</p>

Digital object identifier (DOI): 10.3390/life14101311

Short Stature in Klinefelter Syndrome From Aggrecan Mutation.

<p>Despite tall stature being a characteristic feature of Klinefelter syndrome, occasional cases of short stature have been reported. These cases are often attributed to GH deficiency. This case report details a unique case of a 16-year-old male with Klinefelter syndrome exhibiting proportionate short stature resulting from a heterozygous, likely pathogenic, variant in the ACAN gene c.7141G &gt; A (p.Asp2381Asn). This specific variant, previously identified once in a family with a recessive inheritance pattern is reported here for the first time in an individual with Klinefelter syndrome. This report emphasizes the importance of a thorough evaluation and consideration of genetic testing for an underlying diagnosis in short-statured individuals with Klinefelter syndrome. Timely detection would enable appropriate therapeutic interventions.</p>

Digital object identifier (DOI): 10.1210/jcemcr/luae170

<p>GBS read coverage analysis identified a Robertsonian chromosome from two Thinopyrum subgenomes in wheat, conferring leaf and stripe rust resistance, drought tolerance, and maintaining yield stability. Agropyron glael (GLAEL), a Thinopyrum intermedium\u8201?\u215?\u8201?Th. ponticum hybrid, serves as a valuable genetic resource for wheat improvement. Despite its potential, limited knowledge of its chromosome structure and homoeologous relationships with hexaploid wheat (Triticum aestivum) has restricted the full exploitation of GLAEL's genetic diversity in breeding programs. Here, we present the development of a 44-chromosome wheat/GLAEL addition line (GLA7). Multicolor genomic in situ hybridization identified one chromosome arm from the St subgenome of Th. intermedium, while the other arm remained unclassified. Genotyping-by-sequencing (GBS) read coverage analysis revealed a unique Robertsonian translocation between two distinct Thinopyrum subgenomes, identified as 4StS\u183?1J (vs)S. The GLA7 line demonstrated strong adult plant resistance to both leaf rust and stripe rust under natural and artificial infection conditions. Automated phenotyping of shoot morphological parameters together with leaf relative water content and yield components showed that the GLA7 line exhibited elevated drought tolerance compared to parental wheat genotypes. Three years of field trials showed that GLA7 exhibits similar agronomic performance and yield components to the wheat parents. This unique addition line holds promise for enhancing wheat's tolerance to multiple stresses through the introduction of new resistance genes, as well as its ability to mitigate the effects of temporary water limitation during flowering, all without negatively impacting wheat performance.</p>

Digital object identifier (DOI): 10.1007/s00122-024-04791-x

<p>Human induced pluripotent stem cells (iPSCs) are a valuable tool for studying human development and diseases. iPSCs can be generated by reprogramming from any somatic cells, however establishing primary cell cultures can involve invasive procedures (e.g., skin biopsy) and be labor-intensive. In this paper, we describe an efficient, reliable, and non-invasive method for cultivating primary urine-derived cells (UDCs) and efficiently reprogram them into iPSCs using a feeder-free and non-integrative system. This approach has several advantages: (i) UDCs collection and culture are non-invasive, straightforward, and do not require medical personnel; (ii) reprogramming UDCs using commercially available Sendai viruses is highly efficient and reliable; and (iii) iPSCs generated from UDCs demonstrate strong differentiation potential. To showcase the effectiveness of this method, we generated iPSC lines from UDCs of three control individuals and three patients with Fragile X syndrome.</p>

<p>Chronic lymphocytic leukemia (CLL) exhibits substantial variability in disease course. The mutational status of the B-cell receptor immunoglobulin heavy variable (IGHV) chain is a critical prognostic factor, categorizing patients into mutated (M-IGHV) and unmutated (U-IGHV) groups. Recently, a third subgroup with borderline mutational status (BL-IGHV) has been identified, comprising approximately 5% of CLL cases. This study retrospectively analyzes the outcomes of 30 BL-IGHV mutated patients among a cohort of 653 CLL patients, focusing on time to first treatment (TTFT) and overall survival (OS). BL-IGHV patients had a short TTFT similar to U-IGHV patients (median 30.2 vs. 34 months; p = 0.9). Conversely, the OS of BL-IGHV patients resembled M-IGHV patients (median NR vs. 258 months; p = 1). Despite a similar incidence in unfavorable prognostic factors, the TTFT was shorter compared to other published cohorts. However, striking similarities with other experiences suggest that BL-IGHV mutated patients share common biological characteristics, biased IGHV gene usage and BCR subset frequency. These findings also underscore the need for multicentric efforts aggregating data on BL-IGHV CLL in order to elucidate its disease course and optimize therapeutic approaches for this rare subgroup. Until then, predicting outcomes and optimal management of BL-IGHV CLL will remain challenging.</p>

<p>Advanced strategies to interconvert cell types provide promising avenues to model cellular pathologies and to develop therapies for neurological disorders. Yet, methods to directly transdifferentiate somatic cells into multipotent induced neural stem cells (iNSCs) are slow and inefficient, and it is unclear whether cells pass through a pluripotent state with full epigenetic reset. We report iNSC reprogramming from embryonic and aged mouse fibroblasts as well as from human blood using an engineered Sox17 (eSox17 ). eSox17 efficiently drives iNSC reprogramming while Sox2 or Sox17 fail. eSox17 acquires the capacity to bind different protein partners on regulatory DNA to scan the genome more efficiently and has a more potent transactivation domain than Sox2. Lineage tracing and time-resolved transcriptomics show that emerging iNSCs do not transit through a pluripotent state. Our work distinguishes lineage from pluripotency reprogramming with the potential to generate more authentic cell models for aging-associated neurodegenerative diseases.</p>

Digital object identifier (DOI): 10.1126/sciadv.adh2501

<p>The COVID-19 pandemic forced use of face masks up to billions of masks per day globally. Though an important and necessary measure for control of the pandemic, use of masks also poses some inherent risks. One of those risks is inhalation of microplastics released from the mask materials. Since most of the mask materials are made from plastic/polymers, they always have the potential to expose the user to fragmented microplastics. To estimate the amount of inhalable microplastic exuded from masks, an experiment simulating real-life scenario of mask usage was performed. The study included collection of microplastics oozed out from the masks on to a filter paper followed by staining and fluorescence detection of the total number of microplastics using a microscope. Both used and new masks were studied. Based on the emission wavelength, the microplastics were found to be belonging to three different categories, namely blue, green and red emitting microplastics respectively. The number of microplastic particles emitted per mask over a period of usage of 8 h was about 5000 to 9000 for new masks and about 6500 to 15,000 for used masks respectively. The estimation of polymer type of plastic in the mask fabrics was also carried out using Raman and FTIR spectroscopy.</p>

Digital object identifier (DOI): 10.1007/s11356-022-24702-1

<p>Karyotype divergence may strongly affect the degree of hybridization between species. Western Palearctic slow worms (Anguis) are legless liz- ards forming different types of secondary contact zones. To identify the level of chromosomal variation in slow worms, we examined karyotype in multiple populations of all species except one and Pseudopus apodus as an outgroup. We applied conventional and molecular cytogenetic methods and whole-chromosome painting using macrochromosome probes from Varanus komodoensis to interpret results within the evolu- tionary framework of the common clade Anguiformes. All Anguis species and P. apodus have conserved karyotype structures composed of 44 chromosomes. Despite the conserved chromosome morphology, the phylogenetically oldest Anguis cephallonica living in partial sympatry with Anguis graeca, and parapatric Anguis colchica vs. Anguis fragilis exhibit distinct patterns of constitutive heterochromatin distribution and telo- meric repeat accumulation. In contrast, the sister species A. colchica and A. graeca living in allopatry display highly similar karyotype features. Our findings thus indicate karyotype stasis in Anguis and Pseudopus for &gt; 20 Myr, with fixed species-specific differences present in sympatric and parapatric species. These differences in repetitive DNA patterns may play a role as intrinsic factors co-maintaining species divergence. They may also be used as cytotaxonomic markers to identify slow worm species in practice.</p>

Digital object identifier (DOI): 10.1093/zoolinnean/zlad153

<p><strong>Aims</strong><br /> Chromosomal banding analysis is the standard technique to identify cytogenetic abnormalities in both constitutional chromosomal disorders and hematological malignancies. Karyotyping is a laborious and manual technique. The development of image (metaphases) capture systems and software for karyotyping had a great impact on the routine of cytogenetic laboratories, and recently artificial intelligence (deep neural networks, DNN) has helped in the correct segmentation and chromosome classification, allowing the performance of karyotypes more quickly, with final supervision by experienced cytogeneticists. Some systems using AI are commercially available and our objective was to validate and implement one of these models in our laboratory and measure its productivity.<br /> <strong>Materials and methods</strong><br /> IA DNN –PC/GTX 1650 version 1.1.40 was configured in the automated metaphase image scanning equipment (Metafer), which uses the software for image analysis (Ikaros), all developed by Metasystems (Altlussheim, Germany). Sixteen machine learning models (classifiers) were tested for bone marrow (oncohematological karyotype) and another 16 for peripheral blood (constitutional karyotype), eight of them with the function of chromosome segmentation in metaphase (separation) and 8 of them with the function of classify chromosomes (chromosomal pairing). 55 metaphases from routine studies of bone marrow for hematological malignancies [300-400 bands, 8 with numerical (−Y, −7) or structural (20q−) chromosomal alterations] and 65 metaphases from PHA-stimulated peripheral blood [550 bands, 7 cases with multiple overlapping chromosomes and 9 with numerical (−X, +13, +21) chromosomal alterations]. The time for manual and automated analysis (time for segmentation + classification + review) was compared. The chromosomal mispairing was noted. Productivity was evaluated (percentage difference in seconds manual-automated analysis/ manual analysis in seconds ×100).<br /> <strong>Results</strong><br /> The average time for manual analysis of one metaphase in bone marrow samples was 74 ± 30 seconds (segmentation 34 seconds and classification 40 seconds) and in DNN it was 23 ± 19 seconds (segmentation 13 seconds, classification 10 seconds), with a gain of 51 ± 26 seconds and productivity gain of 68.6%, and mismatch of 1 ± 1.5 chromosomes. The average time for manual analysis of one metaphase in peripheral blood samples was 138 ± 56 seconds (segmentation 85 seconds and classification 52 seconds) and in DNN it was 29 ± 16 seconds (segmentation 15 seconds, classification 14 seconds), with a gain of 108 ± 49 seconds and productivity gain of 78.7%, and pairing error of 2.6 ± 2.<br /> <strong>Discussion</strong><br /> AI allowed a significantly gain in productivity and TAT reduction in karyotype, the constitutional from 21 days to 15 days and the oncohematological karyotype from 14 days to 7 days (5 days for acute leukemias at diagnosis).</p>

Digital object identifier (DOI): 10.1016/j.htct.2023.09.1510

<p>Detection and precise genomic mapping of balanced chromosomal abnormalities in patients with impaired fertility or a clinical phenotype represent a challenge for current cytogenomics owing to difficulties with precise breakpoint localization in the regions enriched for DNA repeats and high genomic variation in such regions. Here, we present a comprehensive cytogenomic approach to breakpoint mapping in a rare paracentric inversion on 10q (in a patient with oligoasthenoteratozoospermia and necrozoospermia) that does not affect other phenotype traits. Multicolor banding, chromosomal microarray analysis, chromosome microdissection with reverse painting, and single-copy sequencing of the rearranged chromosome were performed to determine the length and position of the inverted region as well as to rule out a genetic imbalance at the breakpoints. As a result, a paracentric 19.251 Mbp inversion at 10q22.2q23.3 was described. The most probable location of the breakpoints was predicted using the hg38 assembly. The problems of genetic counseling associated with enrichment for repeats and high DNA variability of usual breakpoint regions were discussed. Possible approaches for cytogenomic assessment of couples with balanced chromosome rearrangements and problems like reproductive failures were considered and suggested as useful part of effective genetic counseling.</p>

Digital object identifier (DOI): 10.3390/biomedicines10123255

<p>Karyotype analysis has a great impact on the diagnosis, treatment and prognosis in hematologic neo-plasms. The identification and characterization of chromosomes is a challenging process and needs experienced personal. Artificial intelligence provides novel support tools. However, their safe and reliable application in diagnostics needs to be evaluated. Here, we present a novel laboratory approach to identify chromosomes in cancer cells using a convolutional neural network (CNN). The CNN identified the correct chromosome class for 98.8% of chromosomes, which led to a time saving of 42% for the karyotyping workflow. These results demonstrate that the CNN has potential application value in chromosome classification of hematologic neoplasms. This study contributes to the development of an automatic karyotyping platform.</p>

Digital object identifier (DOI): https://doi.org/10.1016/j.cancergen.2021.11.005

<p>Protontherapy is a rapidly expanding radiotherapy modality where accelerated proton beams are used to precisely deliver the dose to the tumor target but is generally considered ineffective against radioresistant tumors. Proton-Boron Capture Therapy (PBCT) is a novel approach aimed at enhancing proton biological effectiveness. PBCT exploits a nuclear fusion reaction between low-energy protons and B atoms, i.e. p+ B→ 3α (p-B), which is supposed to produce highly-DNA damaging α-particles exclusively across the tumor-conformed Spread-Out Bragg Peak (SOBP), without harming healthy tissues in the beam entrance channel. To confirm previous work on PBCT, here we report new in-vitro data obtained at the 62-MeV ocular melanoma-dedicated proton beamline of the INFN-Laboratori Nazionali del Sud (LNS), Catania, Italy. For the first time, we also tested PBCT at the 250-MeV proton beamline used for deep-seated cancers at the Centro Nazionale di Adroterapia Oncologica (CNAO), Pavia, Italy. We used Sodium Mercaptododecaborate (BSH) as B carrier, DU145 prostate cancer cells to assess cell killing and non-cancer epithelial breast MCF-10A cells for quantifying chromosome aberrations (CAs) by FISH painting and DNA repair pathway protein expression by western blotting. Cells were exposed at various depths along the two clinical SOBPs. Compared to exposure in the absence of boron, proton irradiation in the presence of BSH significantly reduced DU145 clonogenic survival and increased both frequency and complexity of CAs in MCF-10A cells at the mid- and distal SOBP positions, but not at the beam entrance. BSH-mediated enhancement of DNA damage response was also found at mid-SOBP. These results corroborate PBCT as a strategy to render protontherapy amenable towards radiotherapy-resilient tumor. If coupled with emerging proton FLASH radiotherapy modalities, PBCT could thus widen the protontherapy therapeutic index.</p>

Digital object identifier (DOI): 10.3389/fonc.2021.682647

<p>Telomeres are nucleoprotein complexes protecting chromosome ends in most eukaryotic organisms. In addition to chromosome ends, telomeric-like motifs can be accumulated in centromeric, pericentromeric and intermediate (i.e., between centromeres and telomeres) positions as so-called interstitial telomeric repeats (ITRs). We mapped the distribution of (TTAGGG) repeats in the karyotypes of 30 species from nine families of turtles using fluorescence in situ hybridization. All examined species showed the expected terminal topology of telomeric motifs at the edges of chromosomes. We detected ITRs in only five species from three families. Combining our and literature data, we inferred seven independent origins of ITRs among turtles. ITRs occurred in turtles in centromeric positions, often in several chromosomal pairs, in a given species. Their distribution does not correspond directly to interchromosomal rearrangements. Our findings support that centromeres and non-recombining parts of sex chromosomes are very dynamic genomic regions, even in turtles, a group generally thought to be slowly evolving. However, in contrast to squamate reptiles (lizards and snakes), where ITRs were found in more than half of the examined species, and birds, the presence of ITRs is generally rare in turtles, which agrees with the expected low rates of chromosomal rearrangements and rather slow karyotype evolution in this group.</p>

Digital object identifier (DOI): 10.3390/genes11060657