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Treatment of aplastic anaemia with antilymphocyte globulin and cyclosporin.

Improved survival of patients with aplastic anaemia (AA) has been reported over the last 20 years with immunosuppressive (IS) therapy using antilymphocyte globulin (ALG), and more recently cyclosporin (CSA). The antibody specificities of ALG have now been more clearly defined and are not only T cell directed but also include activities against B cells, NK cells and monocytes. Consequently, the effectiveness of ALG in AA may involve several different mechanisms, and may also help to explain the delayed response that occurs in AA. CSA increases the response rate to ALG in the first 3-6 months, but does not result in improved survival compared with ALG alone. Better supportive care has undoubtedly contributed to the improved survival of patients with time. Almost half the patients who do not respond to a first course of ALG can achieve a later response with a second course of ALG. Relapse occurs in 30% of patients, but up to 50% will respond again with a second course of ALG. Evaluation of the expression of (1) phosphatidylinositol-glycan (PIG)-anchored proteins on haemopoietic cells and (2) gamma-IFN in bone marrow mononuclear cells, may help to predict which patients are more likely to respond to IS therapy. Long term follow up of patients is required to assess the predictive value of X-inactivation DNA studies and PIG-protein expression for later clonal evolution.

Anemia, Aplastic↗

Integrative quantum and systems biology of cancer: From molecular fluctuations to ecological outcomes.

This review treats cancer as a multiscale adaptive system, asks what the framework must predict to be worth adopting, and separates at each scale what the evidence establishes from what is proposed. It is an expert narrative synthesis, not a systematic review, and states the limits of that design. Proton transfer and tautomeric shifts contribute to spontaneous mispairing but do not license claims of directed or non-random mutation: replication timing, three-dimensional chromatin organization, sequence context and known mutagenic processes explain most mutational heterogeneity, leaving any quantum contribution as a residual against that baseline. The Waddington quasi-potential is bounded: outside detailed balance the dynamics are not gradient-derivable and require a probability-flux term. Hysteresis, rate-limited bimodality and return to state after perturbation distinguish an attractor from a transcriptomic cluster. Single-cell karyotype and live-imaging evidence supports whole-genome doubling as an unstable intermediate of heterogeneous origin and context-dependent consequence, not a uniform adaptive strategy. Systems and synthetic biology, virtual cells and digital twins are assessed against benchmarks, not promise. Tissue-scale ecology is reported with the spatial measurements now quantifying it, including evidence that stromal niche construction is not uniformly tumor-supporting. RNA modification is a layer in its own right, showing that the interpretation of a regulatory signal, not its magnitude, is biologically decisive. A dedicated section states the framework's commitments, the observable and evidence at each scale, and what would falsify them, asking what this adds to somatic mutation theory with clonal evolution and plasticity.

Neoplasms↗

M-FISH in gastric lymphoma.

The majority of gastric B-cell lymphomas histologically are classified as low grade mucosa-associated lymphoid tissue (MALT lymphoma) and diffuse large B-cell lymphomas (DLBCL). There is evidence that the different histologic types are genetically heterogeneous, evolving through different pathogenetic pathways. Recurrent cytogenetic aberrations have been found in MALT lymphoma, whereas in DLBCL, limited cytogenetic data are available. We report here a DLBCL and a Burkitt-like gastric lymphoma case, cytogenetically studied by G-banding and M-FISH technique. In the first case, gains of chromosome 3, 7, 13, and 18 were found. An additional ring chromosome 1 identified as a clonal abnormality suggested clonal evolution. In the second case, trisomy 8, del(6)(q13), as well as t(8;14), t(1;5), and t(1;7), were observed. To our knowledge, cytogenetic data for gastric Burkitt-like lymphoma have not been reported, and M-FISH has not previously been used in the study of gastric lymphomas.

Aged↗

Karyotypic characterization of 64 nonmalignant thyroid goiters.

Cytogenetic analyses were performed on 64 nonmalignant thyroid goiters (11 common and 53 multinodular goiters) after short-term culture. The majority of goiters (67%) were characterized by a normal karyotype, but in 5 common (45%) and 16 nodular (30%) goiters, small clones with various numerical and/or structural aberrations were found, in addition to many normal cells. Trisomy or tetrasomy 7 was the most frequent numerical aberration, seen in five cases. Deletion of 18p11 was found in four cases, and in three of them as the sole change. Selection and clonal evolution of aneuploid cells present in nonmalignant goiters could underlie progression into adenoma formation.

Adult↗

High incidence and intraclonal heterogeneity of chromosome 11 aberrations in patients with newly diagnosed multiple myeloma detected by multiprobe interphase FISH.

In multiple myeloma, additional copies of chromosome 11 material, reported to confer an unfavorable prognosis, have been found in 20-45% of patients. To assess the incidence and extent of chromosome 11 aberrations, we performed interphase fluorescence in situ hybridization on CD138+ bone marrow plasma cells of 50 newly diagnosed myeloma patients, using seven locus-specific probes for chromosome 11, one for 13q14.3, and a probe set for translocation t(11;14). In 33 of 50 patients, chromosome 11 aberrations were found. Results indicated a marked intraclonal heterogeneity: in 13 patients, trisomy 11; in 10 patients, subclones with trisomy 11 and partial trisomies 11q coexisted; in 6 patients, only a partial trisomy 11q; and in 6 patients, a tetrasomy or partial tetrasomy 11. The coexistence of subclones with varying extent and copy numbers of chromosome 11 material indicates ongoing structural changes and clonal evolution. Hybridization results delineated 11q23 and 11q25 as the most frequently gained regions, which supports a relevant pathogenetic role of genes on 11q23 and 11q25. To confirm the high incidence of 11q23 gains, a further 50 patients (total n=100) were analyzed for 11q23 and 13q14.3. Myeloma with gains of 11q23 showed a low frequency of deletion 13q14.3 and may prove to be a distinct subgroup of this disease.

Adult↗

Complex chromosomal rearrangements in patients with chronic myeloid leukemia.

During progression of chronic myeloid leukemia (CML) from the chronic to the accelerated phase and/or blast crisis, clonal evolution with nonrandom secondary aberrations such as +8, +Ph, i(17q), +19, -Y, +21, +17, and -7 is frequently observed. Complex chromosomal rearrangements (CCR) are rather rare, and the significance and frequency of different anomalies are poorly understood. The aim of this study was to determine the chromosomes and chromosomal regions which are involved in CCR during progression of the disease and the frequency of nonrandom changes. Conventional cytogenetics, FISH, and multicolor FISH (mFISH) were used to study karyotypes of 18 CML patients with CCR ascertained by G-banding. Most often involved in CCR were chromosomes 2 (x6); 3, 7, and 17 (x5); 1 and 4 (x4); and 5, 6, 11, and 12 (x3); regions 1q, 2q, 5q, 7p, and 17p; and breakpoints 17p11.2 (x3) and 7p15 (x2). There were no recurrent complex translocations. The present findings demonstrate the very high instability of the genome of malignant cells at the chromosomal level. Precise determination of breakpoints involved in CCR can give new dimension to the understanding of genetic mechanisms which play role in progression of malignant disease.

Adult↗

Unusual complex hyperdiploid karyotypes in myelodysplastic syndromes.

Over an 18-year period, 10 myelodysplastic syndrome (MDS) patients with complex hyperdiploid karyotypes were identified. According to the FAB classification, the 10 patients were subclassified as three refractory anemias (RA), three refractory anemias with excess blasts (RAEB), two RAEB in transformation (RAEB-t), and two unclassified MDS. According to the WHO classification, the diagnoses were two RA, one refractory cytopenia with multilineage dysplasia, two RAEB-1, one RAEB-2, two unclassified MDS, and two acute myeloid leukemia. Six were secondary MDS. Four patients showed marked dyserythropoiesis; three of these were secondary MDS. The chromosome number ranged from 47 to 62, and clonal evolution or composite karyotypes were noted in 7 patients. Seven patients had at least one clone with >50 chromosomes. Recurrent defects included chromosome 5, 17, and 13 abnormalities. Notably, trisomy 8 and monosomy 7 were rare in that group of patients. Three of four patients with marked dyserythropoiesis shared abnormalities of both chromosomes 13 and 17.

Aged↗

Differential 14-3-3 sigma DNA methylation and expression in c-myc- and activated H-ras-transformed cells under r- and K-selection.

We cloned rat 14-3-3 sigma, a mediator of p53 tumor suppressor, as a target of K-selection. 14-3-3 sigma expression is suppressed with DNA methylation in breast cancers while its overexpression with hypomethylation is frequent in pancreatic cancers. These opposite findings were recapitulated through r- and K-selection of transformed rat embryo fibroblasts. 14-3-3 sigma expression was suppressed with DNA methylation after r-selection and the gene was overexpressed and demethylated in K-selected cells. 5-aza-2'-deoxycytidine recovered 14-3-3 sigma expression in r-selected cells. The presence of heterogeneous methylation patterns and expression levels before selection suggests that different 14-3-3 sigma expression levels play a role as a prerequisite for selection and clonal evolution.

14-3-3 Proteins↗

Molecular Landscape and Advanced Diagnostic Technologies for BRAF Mutations in Cancer: From Quantitative PCR and ddPCR to CRISPR-Based Platforms.

BRAF mutations are key oncogenic alterations across multiple malignancies, including melanoma, thyroid carcinoma, colorectal cancer, non-small cell lung cancer, glioma, and hairy cell leukemia. The most prevalent variant, BRAF-V600E, induces constitutive activation of the MAPK signaling pathway, promoting tumor progression and influencing therapeutic responsiveness. Accurate detection of BRAF alterations is therefore essential for molecular classification, prognostic assessment, treatment selection, and resistance surveillance. This review summarizes the molecular heterogeneity of BRAF mutations and critically evaluates current diagnostic methodologies. Conventional approaches such as allele-specific PCR and Sanger sequencing are compared with advanced quantitative platforms, including high-resolution melting analysis, droplet digital PCR, and next-generation sequencing, with emphasis on analytical sensitivity, mutation coverage, and clinical applicability. Emerging technologies such as CRISPR-based assays, rolling circle amplification systems, and nanoparticle-based biosensors and point-of-care diagnostic platforms are also discussed for their potential to enhance ultra-sensitive detection, particularly in liquid biopsy settings. These emerging tools are highlighted for their potential to enable ultra-sensitive, rapid, and decentralized mutation detection, particularly in liquid biopsy settings. Key challenges, including intratumoral heterogeneity, low allele-frequency variants, FFPE-associated artifacts, and clonal evolution under therapeutic pressure, are examined within a translational framework. In addition, we examine critical barriers to clinical implementation, including standardization, cost, and global accessibility of molecular diagnostics, and outline potential solutions through scalable technologies and decentralized testing strategies. We propose that optimal BRAF testing requires a mutation subclass-informed and clinically integrated strategy combining comprehensive baseline profiling with longitudinal molecular monitoring. Future diagnostic paradigms will likely integrate multi-omics data and artificial intelligence (AI)-assisted interpretation to refine precision oncology implementation. Looking forward, we propose that optimal BRAF testing will require integration of multi-omics profiling with AI-assisted interpretation, enabling automated variant classification, real-time clinical decision support, and improved prediction of therapeutic response and resistance.

Humans↗

Liquid biopsy: a new window on the BRCA genes.

The Breast Cancer Susceptibility Gene (BRCA)-associated tumors represent a constantly evolving and intriguing scenario in oncology, in which the availability of novel systemic treatment, mainly including the poly (ADP-ribose) polymerase (PARP) inhibitors, has enabled an improved survival benefit in clinical subgroups. The expanding regulatory approvals of PARP inhibitors have inevitably reshaped the clinical indications for BRCA testing, moving the BRCA1/2 profiling from the traditional and preventive workflows to therapeutic paths. Despite advances in technology and treatment, substantial limitations remain in current genetic and genomic tools for the detection of deleterious BRCA1/2 variants. Germline and tumor tissue testing provide only a snapshot of a patient's disease, failing to capture the dynamic and longitudinal aspects of tumor clonal evolution. In this scenario, liquid biopsy (LB) profiling of BRCA1/2 genes, primarily as circulating tumor DNA, represents a highly active area of research potentially affecting many aspects of cancer screening, diagnosis, and monitoring in individuals who are carriers of BRCA1/2 deleterious variants. Beyond the attractive potential to surrogate the tumor tissue testing, to overcome the cancer spatial and temporal heterogeneity, and to monitor the tumor mutational profile over time, accurately detecting all clinically relevant BRCA genetic variants and epigenetic modifications using LB remains technically challenging.

BRCA1/2↗

Rectal adenocarcinoma with choriocarcinomatous differentiation: clinical and genetic aspects.

Nongestational choriocarcinomas are rare tumors. In the gastrointestinal tract, they are characterized by a biphasic tumor growth with separated areas of adenocarcinomatous and choriocarcinomatous differentiation. We here report a case of a combined adenocarcinoma-choriocarcinoma of the rectum. The tumor showed an aggressive clinical behavior with metastasis to the liver and lungs. A transient partial remission was achieved after 4 cycles of cisplatinum, etoposide, and ifosfamide chemotherapy, with normalization of serum beta-human chorionic gonadotropin levels. At this time, viable residual choriocarcinoma cells were found in surgically resected lung metastasis. The patient succumbed 8 months after initial diagnosis to a rapid abdominal relapse. We used comparative genomic hybridization (CGH) and fluorescence in situ hybridization to elucidate the genetic relationship of adenocarcinoma and choriocarcinoma in this neoplasm. We found genetic changes characteristic for colorectal adenocarcinomas, a loss of chromosomal regions 8p21-pter as well as 18q21-pter, and a gain of 5p and 20q, in both tumor parts. This provides evidence for the common origin of both components. A differential pattern of additional genetic changes suggests a clonal evolution from a common ancestor cell. In contrast to findings from a comparative study on a choriocarcinoma of the renal pelvis, we did not find an amplification of the germ cell cancer-associated chromosomal region 12p11.2-p12.1 in the areas of choriocarcinoma but found instead a loss of Xp11.3-pter. To our knowledge, this is the first report of a CGH comparison of the adenocarcinomatous and choriocarcinomatous tumor parts in a nongestational choriocarcinoma of the gastrointestinal tract.

Adenocarcinoma↗

Molecular evidence for progression of nephrogenic metaplasia of the urinary bladder to clear cell adenocarcinoma.

Nephrogenic metaplasia or nephrogenic adenoma of the urinary tract may present a diagnostic challenge in surgical pathology practice. Previous case reports suggest the possibility of nephrogenic metaplasia progressing to clear cell adenocarcinoma, but a malignant potential of nephrogenic metaplasia is generally not acknowledged. A case of a 70-year-old female patient with multiple recurrences of nephrogenic metaplasia of the urinary bladder and subsequent development of clear cell adenocarcinoma is described. Immunohistochemical studies help to differentiate the 2 entities. Results of molecular studies, particularly comparative genomic hybridization analysis, suggest clonal evolution of nephrogenic metaplasia to clear cell adenocarcinoma in this case.

Adenocarcinoma, Clear Cell↗

"Acute myelogenous leukemia like" translocations in CML blast crisis: two new cases of inv(16)/t(16;16) and a review of the literature.

We describe two patients with CML blast crisis with clonal evolution affecting 16q22 (t(16;16)(p13;q22) and inv(16)(p13;q22), abnormalities of core binding factor, usually found in de novo acute myeloid leukemia (AML)). The bone marrow of both cases showed myelomonocytic (M4) differentiation and eosinophilia. Both patients had prominent extramedullary disease and had poor response to treatment. A literature search focused on patients with CML and additional chromosome changes more typical of AML, revealed that the morphology of the blasts correlated with the finding typical of the underlying "AML" cytogenetic abnormality and an overall very poor clinical outcome, even in the groups with "favorable" AML type translocations.

Blast Crisis↗

Development of cancer chemopreventive drugs based on mechanistic approaches.

One of the most important medical practices of the 21st century is the chemoprevention of cancer. Much progress has been made in this new emerging field, but much work remains before widespread use and practice of cancer prevention becomes commonplace. Cancer chemoprevention includes the concepts of inhibition, reversal, and retardation of the cancer process. The process of carcinogenesis requires 20-40 years to reach invasive cancer. This process follows multiple, diverse, and complex pathways in a stochastic process, called clonal evolution. Many of these pathways appear amenable to inhibition, reversal, or retardation at various points. It is urgent that we identify key pathways in the evolution of the cancer cell, which can be exploited to prevent this carcinogenesis process. Basic researchers are identifying many genetic lesions and epigenetic processes associated with the progression of precancer to invasive disease. These precancer lesions are also called intraepithelial neoplasia (IEN). Many of these early precancerous lesions favor cell division over quiescence and protect cells against apoptosis when signals are present. Many oncogenes, which are active during early development, are reactivated in adulthood by aberrant gene promoting errors. Normal regulatory genes can become mutated, making them insensitive to normal regulatory signals. Tumor suppressor genes are deleted or mutated rendering them inactive. These are several of a wide range of defects in cellular machinery, which can lead to evolution of the cancer phenotype. Errors may not have to appear in a defined order for cells to progress along the cancer pathway. To conquer this diverse disease, it is necessary to attack multiple key pathways at once for a predetermined period of time. Agent combination prevention strategies are, therefore, essential to decrease cancer morbidity. Each cancer type, organ location, or individual genetic background may require a custom combination of prevention strategies to be successful.

Anticarcinogenic Agents↗

Structural complexity and mechanistic diversity of MECOM rearrangements in myeloid neoplasms.

Rearrangements involving MECOM at chromosome 3q26.2 are recurrent in myeloid neoplasms, classically represented by inv(3)(q21q26.2) and t(3;3)(q21;q26.2), which reposition the GATA2-distal haematopoietic enhancer and drive aberrant EVI1 overexpression. However, the full structural and mechanistic diversity of MECOM rearrangements (MECOM-r) is yet to be explored. We retrospectively analysed 97 cases with cytogenetically defined MECOM-r and identified 12 with complex rearrangements using GTG-banded karyotyping and tri-colour interphase/metaphase fluorescence in situ hybridisation analyses. These 12 cases demonstrated remarkable structural heterogeneity. The abnormalities encompassed translocations, inversions, insertions, duplications, and deletions, which often coexisted within the same specimen as multiple rearranged subclones. Insertional events emerged as a distinct mechanism of MECOM activation. These encompassed insertions of MYNN and/or MECOM into chromosomes 1 and 6, insertion of chromosome 8 segment into MECOM, and inverted insertions between homologous chromosome 3 segments. Recurrent breakpoints at 3q21 across multiple cases, together with localised copy number imbalances frequently involving the MYNN and GOLIM4 loci at 3q26.2, underscore the architectural fragility of these two regions. Co-occurring abnormalities such as -5/del(5q), -7/del(7q), and TP53 loss were common, reflecting a permissive genomic background for chromosomal reassembly. Our findings expand the mechanistic landscape of MECOM-r beyond canonical inv(3)/t(3;3), establishing 3q21 and 3q26.2 as structural 'hotspots' and genomic instability hubs. Distinct from fusion-driven oncogenes such as KMT2A, MECOM activation results from enhancer hijacking and regional structural remodelling, leading to EVI1 overexpression and clonal evolution in myeloid malignancies.

Humans↗

Integrated morphologic, immunophenotypic, and molecular profiling of advanced upper tract urothelial carcinoma across tumor compartments supports biopsy-based testing.

Upper tract urothelial carcinoma (UTUC) is an aggressive malignancy with limited molecular characterization in advanced disease. FGFR3 alterations are well established in low-grade urothelial carcinoma, but their prevalence, stability, and biological significance in locally advanced and metastatic UTUC remain only partially defined. We performed an integrated morphologic, immunohistochemical, and molecular analysis of 24 locally advanced and/or metastatic UTUC from 20 patients. FGFR3 status was assessed by RT-PCR across multiple tumor compartments, including biopsies, primary tumors, lymph-node metastases, and distant metastatic sites. Immunohistochemistry included CK20, CK5, GATA3, p53, and mismatch repair proteins. Targeted next-generation sequencing (NGS) was used to characterize co-occurring genomic alterations and to assess concordance with p53 immunophenotype. FGFR3 alterations were identified in 50% of patients and in 54.2% of analyzed tumors. FGFR3 status showed high intra-patient stability, with concordance between primary tumors and distant metastases in 90% of cases, whereas concordance with lymph node metastases was lower (50%), suggesting site-specific clonal divergence. Despite advanced stage, 92.3% of FGFR3-altered tumors displayed papillary urothelial carcinoma morphology, and most showed a luminal immunophenotype (61.5% by CK20/CK5 and 69.2% by GATA3/CK5). Targeted NGS revealed additional pathogenic alterations in 75% of patients, most frequently involving RTK/RAS/MAPK signaling (70%), cell-cycle regulation (25%), and PI3K/AKT pathway components (10%). TP53 mutations co-occurred with FGFR3 alterations in 60% of FGFR3-mutated patients and showed 90.4% concordance with p53 immunohistochemistry. Finally, a few cases exhibited complex, multi-site FGFR3 mutational patterns, consistent with intratumoral clonal evolutions. In conclusion, FGFR3 alterations are frequent and remarkably stable in advanced UTUC, even in high-grade and metastatic disease. These findings support the reliability of FGFR3 testing on limited diagnostic material and reinforce its relevance for therapeutic stratification. UTUC emerges as a molecularly dynamic disease in which early oncogenic drivers such as FGFR3 continue to shape tumor biology and therapeutic vulnerability at advanced stages.

Humans↗

Cytogenetic and molecular genetic characterization of immortalized human ovarian surface epithelial cell lines: consistent loss of chromosome 13 and amplification of chromosome 20.

OBJECTIVES: This study aimed at identifying the genetic events involved in immortalization of ovarian epithelial cells, which might be important steps in ovarian carcinogenesis. METHODS: The genetic profiles of five human ovarian surface epithelial (HOSE) cell lines immortalized by retroviral transfection of the human papillomavirus (HPV) E6/E7 genes were thoroughly characterized by chromosome banding and fluorescence in situ hybridization (FISH), at various passages pre- and post-crisis. RESULTS: In pre-crisis, most cells had simple, non-clonal karyotypic changes. Telomere association was the commonest aberration, suggesting that tolermase dysfunction might be an important genetic event leading to cellular crisis. After immortalization post-crisis, however, the karyotypic patterns were non-random. Loss of genetic materials was a characteristic feature. The commonest numerical aberrations were -13, -14, -16, -17, -18, and +5. Among them, loss of chromosome 13 was common change observed in all lines. The only recurrent structural aberration was homogeneously staining regions (hsr) observed in three lines. FISH and combined binary ratio labeling (COBRA)-FISH showed in two cases that the hsrs were derived from chromosome 20. Clonal evolution was observed in four of the lines. In one line, hsr was the only change shared by all subclones, suggesting that it might be a primary event in cell immortalization. CONCLUSION: The results of the present study suggested that loss of chromosome 13 and the amplification of chromosome 20 might be early genetic events involved in ovarian cell immortalization, and might be useful targets for the study of genomic aberrations in ovarian carcinogenesis.

Cell Line, Transformed↗

Gain of 1q is associated with adverse outcome in favorable histology Wilms' tumors.

Although several genes/genetic loci involved in the etiology of Wilms' tumor have been identified, little is known of the molecular changes associated with relapse. We therefore undertook an analysis by comparative genomic hybridization (CGH) of 58 tumor samples of favorable histology Wilms' tumor taken at initial diagnosis and/or relapse. Tumors with anaplastic histology were excluded as this is known to be associated with p53 mutation and a poor prognosis. A control group of 21 Wilms' tumors that did not relapse was also analyzed. The overall frequency of gains or losses of genetic material detected by CGH was similar in both groups (77% in relapsing tumors and 70% in the nonrelapse group) as was the median number of changes per tumor (relapse group: n = 4, range, 1 to 19; nonrelapse group: n = 3, range, 1 to 8). However, gain of 1q was significantly more frequent in the relapse series [27 of 46 (59%) versus 5 of 21 (24%), P: = 0.019]. In 12 matched tumor pairs, the CGH profiles, including 1q gain, were similar at diagnosis and relapse, with little evidence for further copy number changes being involved in clonal evolution. The results suggest that 1q gain at diagnosis could be used to identify patients with favorable histology Wilms' tumor at increased risk of relapse who might benefit from early treatment intensification.

Chromosome Aberrations↗