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At least 19 recordsLinked to original sources
PubMed1986

In vitro immune interferon induction during tumor evolution.

In a syngeneic C3H mammary adenocarcinoma model we studied gamma-interferon (gamma IFN) production during tumor evolution. The IFN production was induced by soluble tumor extracts on spleen cell cultures from tumor-bearing mice. A low level of IFN production was found in culture supernatants from small tumor-bearing mice (tumor diameter less than 10 mm, 12-15 days of tumor evolution). In advanced stages of tumor growth (diameter more than 15 mm, 20 days or more of tumor evolution), this ability was lost.

Adenocarcinoma↗
PubMed2025

Unraveling cellular dynamic changes in tumor evolution induced by long-term low dose-rate radiation.

BACKGROUND: In recent years, there has been a steady increase in professionals engaged in radioactive work. The biological impacts of long-term exposure to low dose-rate radiation remain elusive, as there is a dearth of systematic research in this field. METHODS: BEAS-2B cells were used to establish a cell model with continuous passaging after radiation exposure, which was subsequently subjected to in vivo tumorigenesis assays and in vitro malignant phenotype experiments. By scRNA-seq, we conducted copy number variation analysis, cell trajectory analysis, and cell communication analysis. Furthermore, we used FACS, molecular docking, multiplex immunohistochemistry, qRT-PCR, and co-immunoprecipitation to validate and further explore the molecular mechanisms driving tumor evolution. RESULTS: Long-term low dose-rate exposure is associated with a higher degree of malignancy, as evidenced by the induction of more CNV and EMT events, as well as the delayed activation of DNA repair pathways, which trigger increased genomic instability. The long-term low dose-rate specific ligand-receptor pair, ANGPTL4-SDC4, enhances cell malignancy by promoting angiogenesis in newly formed lung tumor cells. CONCLUSIONS: This study not only provides the first evidence and mechanistic explanation that long-term low dose-rate radiation leads to increased cellular malignancy but also offers valuable theoretical insights into the dynamic processes of early tumor evolution in lung cancer within the realm of tumor biology.

Humans↗
PubMed2026

Chromosome-scale genome remodeling in tumor evolution: Copy number alterations and structural variants as two sides of the same coin.

Chromosome-scale genomic rearrangements are a dominant force in tumor evolution. Copy-number alterations (CNAs) and structural variants (SVs) constitute two complementary axes of this process. Although detection technologies now deliver near-comprehensive catalogs, technical resolution has outpaced conceptual integration. In this review, we frame CNAs and SVs as inextricable facets of chromosomal aberrations. They reshape cancer genomes through altered gene dosage and three-dimensional regulatory rewiring. CNAs quantify the gene-dosage imbalance, yet arise through mechanistically distinct routes. Segmental CNAs typically require chromosomal breakage, and therefore often coincide with SV junctions. By contrast, whole-chromosome aneuploidy and whole-genome doubling (WGD) primarily reflect mitotic or cytokinetic failure and can occur without local breakpoints, while nevertheless reshaping the karyotypic landscape and seeding subsequent structural complexity. SVs, in turn, range from unbalanced events that alter copy number to ostensibly balanced exchanges that predominantly rewire regulatory architecture. Despite their diverse and sometimes catastrophic architectures, SVs are ultimately rooted in double-strand break formation and error-prone resolution. By integrating CNAs and SVs within a unified mechanistic and functional framework, we aim to convert catalogs into concepts and distill the organizing principles that govern tumor genome evolution.

Humans↗
PubMed2026

Tumor evolution shapes metastatic competence in colorectal cancer.

In this issue of Cancer Cell, Manca et al. investigate the genomic evolution and metastatic tropism of over 7,000 colorectal cancers. Integrating primary tumor location, genomic alterations, and clinical variables, they reveal how distinct patterns of tumor evolution shape metastatic competence and impact organ tropism, offering a framework to refine surveillance.

Humans↗
PubMed2025

SISTEM: simulation of tumor evolution, metastasis, and DNA-seq data under genotype-driven selection.

SUMMARY: SISTEM is a software package and mathematical framework for simulating tumor evolution and cell migrations at single-cell resolution. Unlike existing frameworks which simulate cancer cell populations under the neutral coalescent or using simple birth-death models, SISTEM simulates tumor populations under somatic clonal selection using an agent-based framework. SISTEM can generate mutation profiles, read counts, and DNA sequencing reads along with ground truth cell lineages and migration graphs under a number of easily customizable mutation and selection models. For improved realism, SISTEM allows for cell fitness to be driven by genomic events of various scales including single nucleotide variants, segmental gains and losses, whole-chromosomal and chromosome-arm aberrations, and whole-genome duplications. SISTEM also includes numerous migration models to simulate metastatic cancers, facilitating the exploration and evaluation of diverse migration patterns. AVAILABILITY AND IMPLEMENTATION: SISTEM is written in Python and is freely available open-source under GNU GPLv3 from: https://github.com/samsonweiner/sistem.

Software↗
PubMed2005

Heterogeneous tumor evolution initiated by loss of pRb function in a preclinical prostate cancer model.

Because each change in the evolution of a cancer is predicated on the effects of previous events, a full understanding of selective changes and their effect on tumor progression can only be understood in the context of appropriate initiating events. Here, we define the effect of pRb function inactivation in prostate epithelium on both the initiation of prostate cancer and the establishment of selective pressures that lead to diminished Pten function and tumor evolution. Using genetically engineered mice, we show that inactivation of the pRb family proteins (Rb/p107/p130) induces epithelial proliferation and apoptosis and is sufficient to produce prostatic intraepithelial neoplasia (PIN) lesions. Over time, adenocarcinomas develop in all mice with no evidence of neuroendocrine tumors. Apoptosis is dependent on Pten function and not p53, unlike other epithelial cell types tested previously. Consequently, Pten hemizygosity reduces apoptosis by 50%, accelerating progression to adenocarcinomas with heterogeneous composition. Heterogeneity is associated with concurrent Pten haploinsufficiency and focal selective progression to complete Pten loss, which yields distinct tumor properties. Given that this analysis models the apparent timing of highly penetrant events in human prostate cancer, observed effects may recapitulate the natural evolution of prostate cancer development.

Adenocarcinoma↗
PubMed1977

Immune surveillance against virus-induced tumors and nonrejectability of spontaneous tumors: contrasting consequences of host versus tumor evolution.

Spontaneous tumours are defined as tumors that develop in the absence of all experimental interference. In contrast to the widely documented, strong rejection reactions against most virus-induced tumors, spontaneous tumors evoke little or no detectable rejection reaction in intact or preimmunized syngeneic hosts. The difference can be viewed in relation to the contrasting natural history of the two conditions. Spontaneous tumors evolve in several steps, as a fule. "Tumor progression" is a microevolutionary process at the level of the somatic tissue where successive clonal variants replace each other. Each new variant gains the upper hand due to its greater independence of some restricting host mechanism. Independence of immune restrictions must be part of this process. Host selection for immune resistance apparently plays no major role here, presumably because most of the naturally occurring tumors arise after the host has passed the peak of its reproductive period. Protection against the oncogenic effects of ubiquitous tumor viruses is, on the other hand, the result of host selection for immune mechanisms favoring prompt rejection of virus-transformed cells. This is neither synonymous with nor related to protection against the viral infection per se, which is frequently successful and usually quite harmless. A certain relationship can be perceived between the degree of viral ubiquity and the strength of immune protection against the corresponding tumor cells. Natural selection for host recognition of commonly occurring, virally induced changes in neoplastic cell membranes can be surmised to occur, at least in part, by the fixation of appropriate immune responsiveness (Ir) genes. The role of Ir genes for tumor recognition can be approached by the genetic analysis of the F1 hybrid resistance effect. Unresponsiveness to spontaneous tumors may be overcome by target-cell modification, e.g., by chemical coupling, somatic cell hybridization, or viral "xenogenization".

Animals↗
PubMed1986

Cytogenetic heterogeneity: its role in tumor evolution.

There is ample evidence that cytogenetic heterogeneity characterizes human solid tumors, despite the opposing influences of clonal origin and selection for tumor-specific chromosome aberrations. Different chromosome patterns are found within individual tumors and among phenotypically similar tumors. Some tumor cell populations contain mixtures of diploid and cytogenetically aberrant cells; others display multiple aberrant clones. The extent and biological significance of chromosomal heterogeneity is contrasted between examples of leukemias and of selected solid tumors (mainly of breast and central nervous system origin). Increasing degrees of chromosomal aberration appear correlated with increasingly malignant biological properties of tumors. Genic and chromosomal instability are potential sources for genetic diversity within all tumors. However, variations in local selective forces and differential survival within an expanding solid lesion may contribute to maintenance of a mixed cell population within the primary tumor. In turn, the resulting heterogeneity may permit selection and increase of aberrant cells that are responsible for tumor progression and metastasis.

Brain Neoplasms↗
PubMed1997

Patterns of cytokine evolution (tumor necrosis factor-alpha and interleukin-6) after septic shock, hemorrhagic shock, and severe trauma.

OBJECTIVE: To compare the patterns of evolution of two proinflammatory cytokines (tumor necrosis factor [TNF]-alpha and interleukin-6 [IL-6]) in two major clinical entities associated with systemic inflammatory response: septic shock and multiple trauma (with and without hemorrhagic shock). DESIGN: Prospective study of two cohorts of patients. SETTING: Critical care unit and Emergency Center of a university hospital. PATIENTS: Twenty-five nontrauma patients with septic shock and 60 multiple trauma patients (of whom eight patients were resuscitated from hemorrhagic shock). INTERVENTIONS: Serial blood samples were collected in each patient for determination of serum cytokine concentrations. Samples were obtained over 7 days in septic shock patients and 11 days in trauma patients. Standard resuscitation techniques were used in each patient. Clinical and laboratory data were prospectively collected. MEASUREMENTS AND MAIN RESULTS: High concentrations of circulating TNF-alpha and IL-6 were found in patients with septic shock. High IL-6 concentrations, but normal TNF-alpha concentrations were detected in trauma patients. At study entry, TNF-alpha concentrations were higher in nonsurvivor septic shock than in nonsurvivor trauma patients (42 +/- 7 vs 13 +/- 2 pg/mL; p < .001). During the whole study period, nonsurvivor septic shock patients maintained higher TNF-alpha concentrations than nonsurvivor trauma patients (p < .001). In survivors in both groups, normal values for TNF-alpha were detected during the whole study period. At study entry, IL-6 concentrations were significantly higher in nonsurvivor septic shock patients than in nonsurvivor trauma patients (15,627 +/- 4336 vs. 317 +/- 124 pg/mL; p < .0001). During the whole study period, much higher concentrations of IL-6 were detected in septic shock patients than in trauma patients (p < .0001). In survivors, at study entry, IL-6 concentrations were much higher in septic shock patients than in trauma patients (3947 +/- 1410 vs. 247 +/- 41 pg/mL; p < .001). Higher IL-6 concentrations were maintained throughout the study period in septic shock patients than in trauma patients (p < .001). In septic shock patients, changes in both TNF-alpha and IL-6 were correlated with outcome, higher values being found in patients likely to die. Neither TNF-alpha nor IL-6 values were of any significant value in predicting outcome of trauma patients. When septic shock patients were compared with traumatized patients resuscitated from hemorrhagic shock, the former had much higher concentrations of both TNF-alpha and IL-6 throughout the study period (p < .01 to p < .00001). Increased IL-6 values were an indicator of the development of a nosocomial infection in trauma patients. In five trauma patients who developed a nosocomial pneumonia during the study period, the IL-6 concentration was 433 +/- 385 pg/mL before the onset of pneumonia, then peaked at 3970 +/- 1478 pg/mL on day 7, and returned to baseline (219 +/- 58 pg/mL) on day 11. CONCLUSIONS: In septic shock patients, high amounts of circulating TNF-alpha and IL-6 are found and then correlate with fatal outcome. In trauma patients (even those patients resuscitated from hemorrhagic shock), much less increased concentrations of IL-6 are detected while normal TNF-alpha circulating concentrations are measured. In these patients, cytokine concentrations do not correlate with outcome. This finding suggests a much higher degree of activation of the immunoinflammatory cascade in septic shock than in multiple trauma patients. Increased IL-6 values are an indicator of the development of a nosocomial infection in trauma patients.

Adult↗
PubMed2004

Cryoablation of benign breast tumors: evolution of technique and technology.

We report on improvements in cryoprobe design and techniques of cryoablation as a minimally invasive alternative to open surgery for the treatment of benign breast tumors. In the study, which was conducted in 12 centers, 124 lesions in 102 patients were monitored for a period of 12 months after cryoablation. Two different treatment techniques were used: Double HI FREEZE and Tailored Freeze. In patients treated with the Tailored Freeze technique significantly better results were recorded 12 months after the procedure: the median reduction in tumor volume was 91%, 73% of all tumors treated were nonpalpable, 84% of lesions less than 2.5 cm in maximum diameter were nonpalpable, and none of the 31 mammograms performed yielded abnormal findings. Patient satisfaction was good to excellent in 92% of the patients. The safety profile of this technique was excellent; all complications were minor. Evolution of cryoablation freezing techniques, coupled with improvements in cryoprobe design, has resulted in significant improvements in both safety and effectiveness.

Adult↗
PubMed2026

Competing subclones and fitness diversity shape tumor evolution across cancer types.

MOTIVATION: Intratumor heterogeneity arises from ongoing somatic evolution and complicates cancer diagnosis, prognosis, and treatment. Reconstructing evolutionary dynamics typically requires spatiotemporal samples, which are often unavailable in clinical settings. Computational approaches that can infer tumor evolutionary history from single-timepoint bulk sequencing data remain limited. RESULTS: We present estimating evolutionary events through single-timepoint sequencing (TEATIME), a novel computational framework that models tumors as mixtures of two competing cell populations: an ancestral clone with baseline fitness and a derived subclone with elevated fitness. Using cross-sectional bulk sequencing data, TEATIME estimates mutation rates, timing of subclone emergence, relative fitness, and number of generations of growth. To quantify intratumor fitness asymmetries, we introduce a novel metric-fitness diversity-which captures the imbalance between competing cell populations and serves as a measure of functional intratumor heterogeneity. Applying TEATIME to 33 tumor types from The Cancer Genome Atlas, we revealed divergent as well as convergent evolutionary patterns. Notably, we found that immune-hot microenvironments constraint subclonal expansion and limit fitness diversity. Moreover, we detected temporal dependencies in mutation acquisition, where early driver mutations in ancestral clones epistatically shape the fitness landscape, predisposing specific subclones to selective advantages. These findings underscore the importance of intratumor competition and tumor-microenvironment interactions in shaping evolutionary trajectories, driving intratumor heterogeneity. Lastly, we demonstrate that TEATIME-derived evolutionary parameters and fitness diversity offer novel prognostic insights across multiple cancer types. AVAILABILITY AND IMPLEMENTATION: R implementation of TEATIME is available on GitHub (https://github.com/liliulab/TEATIME) and Zenodo (https://zenodo.org/records/17422174).

Neoplasms↗
PubMed1999

A study of loss of heterozygosity at 70 loci in anaplastic astrocytoma and glioblastoma multiforme with implications for tumor evolution.

Cancers that arise from astrocytes in the adult CNS present as either anaplastic astrocytomas (AAs) or as more aggressive glioblastomas multiforme (GBMs). GBMs either form de novo or progress from AAs. We proposed to examine the molecular genetic relationship between these CNS tumors by conducting a genome-wide allelic imbalance analysis that included 70 loci on examples of AA and GBM. We found significant loss of heterozygosity (LOH) at 13 discrete chromosomal loci in both AAs and GBMs. Loss was significant in both AAs and GBMs at 9 of these loci. AAs show the highest rates of LOH at chromosomes 1p, 4q, 6p, 9p, 11p, 11q, 13q, 14q, 15p, 17p, 17q, and 19q. GBMs showed the greatest losses at 1p, 6q, 8p, 9p, 10p, 10q, 11p, 13q, 17p, 17q, 18p, 18q, and 19q. GBMs also demonstrated significant amplification at the epidermal growth factor receptor locus (7p12). These data suggest that there are three classes of loci involved in glioma evolution. First are loci that are likely involved in early events in the evolution of both AAs and GBMs. The second class consists of AA-specific loci, typified by higher LOH frequency than observed in GBMs (4q, 6p, 17p, 17q, 19q). The third class consists of GBM-specific loci (6q, 8p, 10, 18q). Damage at these loci may either lead to de novo GBMs or permit existing AAs to progress to GBMs. Glioma-related LOH profiles may have prognostic implications that could lead to better diagnosis and treatment of brain cancer patients.

Astrocytoma↗
PubMed1995

[Renal-cell adenocarcinoma as an incidental finding. Its diagnosis and tumor evolution].

OBJECTIVES: We attempted to determine whether or not incidental renal cell carcinoma had a better prognosis. METHODS: We reviewed 53 cases of renal cell carcinoma that had been surgically treated over the periods 1985-1988 and 1989-1993. The form of presentation, stage of the incidental tumors, sex, compromised side and the diagnostic imaging technique utilized were analyzed. RESULTS: GI pathology most frequently led to the diagnosis of the tumor. Tumor stages were A or B with a slightly higher prevalence for the incidental tumors. However, the prognosis was not better than that of clinically suspected renal cell carcinoma. The male to female ratio was 1.17:1, the mean age was 63 years, the tumors were frequently right-sided and ultrasound was superior in the diagnosis of incidental tumors. CONCLUSIONS: No prognostic difference was observed between clinically suspected and incidental renal cell carcinoma of the same tumor stage.

Adult↗
PubMed1993

A general model of carcinogenesis (I)--Tumor evolution and gene deletion.

Carcinogenesis is functionally a deletion alteration rather than addition of genetic information. Repressor genes may be more sensitive to 'neutral' mutations of DNA than those of structural genes, since selection pressure for deletion of repressors is extremely low in multicellular organisms. Dysfunction of repressors caused by genomic mutation induces autonomic expression of structural genes which is programmed a priori in each cell. Tumor progression can be explained by this deletion model with abnormal DNA repair. Alteration of DNA repairing units may be the initial mutation in carcinogenesis.

Animals↗
PubMedDate not supplied

[Hartmann's procedure in colorectal tumors. Evolutions of the indications in a series of 46 patients].

The Authors report a retrospective study of 46 cases of Hartmann's operation in order to analyze the changing indications to this procedure in the management of colo-rectal cancer. The Hartmann's is operation has been performed in 46 out of 723 patients (6.4%) with colorectal cancer treated surgically from 1973 to 1997. Data concerning the indications have been analyzed in two consecutive periods, from 1973 to 1985 and from 1986 to 1997, respectively. In the first period, the procedure has been performed in patients with neoplastic perforation (40% of Hartmann's cases), and in an elective basis in patients with locally invasive tumor or intra-abdominal metastasis (20%). Indications for the procedure in the period 1986-1997 have been locally invasive tumor and/or distant metastasis (52.8% of Hartmann's procedures), neoplastic perforation (22.2%), high surgical anaesthesiologic risk (22.2%) or intestinal obstruction (2.8%). In the second period it has been noted a decrease of the number of patients that underwent Hartmann's procedure for bowel obstruction, and an increase in the number of cases in which the operation was performed for neoplastic perforation, for local and/or distant diffusion, or for high surgical risk.

Aged↗