PubMed HealthSearch

SEARCH · PubMed Health

Results for “Genes, Neoplasm”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Analysis of rat repetitive DNA sequences.

Parameters of repetitive sequence organization have been measured in the rat genome. Experiments using melting, hydroxylapatite binding, and single strand specific nuclease digestion have been used to measure the number, length, and arrangement of repeated DNA sequences. Renaturation and melting or S1 nuclease digestion of 1.0 kbp DNA fragment show about 20% of rat DNA sequences are 3000-fold repeated. Renatured duplexes from 4.0 kbp DNA fragments display two repetitive size fractions after nuclease digestion. About 60% of the repeated sequences are 0.2-0.4 kbp long while the remainder are longer than 1.5 kbp. The arrangement of the repeated sequences has been measured by hydroxylapatite fractionation of DNA fragments of varying lengths bearing a repeated sequence. Repeated DNA sequences are interspersed among 2.5 kbp long nonrepeated sequences throughout more than 70% of the rat genome. There are approximately 350 different 3000-fold short repeated sequences in the rat interspersed among 600,000 nonrepeated DNA sequences.

Animals

Passage of phenotypes of chemically transformed cells via transfection of DNA and chromatin.

DNA was prepared from 15 different mouse and rat cell lines transformed by chemical carcinogens in vitro and in vivo. These DNAs were applied to NIH3T3 mouse fibroblast cultures by using the calcium phosphate transfection technique. DNAs of five donor lines were able to induce foci on the recipient monolayers. Ten other donor DNAs yielded few or no foci. DNAs from control, nontransformed parental cell lines induced few or no foci. Chromosomes were transfected from one donor whose naked DNA was unable to induce foci, and morphologic transformation of recipients was observed. These experiments prove that in five of these cell lines the chemically induced phenotype is encoded in DNA, and the sequences specifying the transformed phenotype behave as a dominant allele in the NIH3T3 recipient cells. The sequences encoding the transformation are likely found on a single fragment of DNA.

Alleles

Single-cell multimodal profiling of pan-cancer cell lines uncovers gene regulatory principles underlying intrinsic cell states and environmental features.

Cancer arises from genetic and epigenetic alterations that reshape chromatin, transcriptional regulation, and malignant cell states. To chart cancer-intrinsic regulatory programs, we build a pan-cancer single-cell atlas of 60 cancer cell lines spanning 16 tissue origins and 20 cancer types, comprising 240,957 snRNA-seq and 223,347 snATAC-seq profiles. Integrative analyses reveal cell-state heterogeneity, core gene-regulatory networks, and a conserved EMT axis transcending tissue of origin; copy-number analysis identifies transcription factor amplification and hyperactivation as drivers of state reprogramming. Comparing cutaneous melanoma with acral melanoma, a rare subtype underrepresented in previous studies, uncovers a universal inflammation-suppressive program in acral and an inflamed landscape in cutaneous melanoma, with JAK-STAT activity as the central discriminator. Integrating data across models and patient cohorts links tumor-intrinsic regulation to microenvironmental composition and therapeutic response. By profiling rare alongside common subtypes, this atlas offers a resource for mapping pan-cancer and subtype-specific regulatory programs shaping cell-state plasticity.

Humans

The offonome reveals on and off states of gene expression near the detection limit of RNA-seq.

RNA-seq, widely used for gene expression profiling, provides nucleotide level genome coverage and summary gene expression values. Generally, low-expressed genes are ignored due to their unfavorable signal-to-noise ratio, however, these genes may offer crucial information, such as detecting rare cells in bulk tissues. In this study, we applied an approach that transforms the expression levels of low-expressed genes into a robust dichotomized on/off state by leveraging similarities in transcript coverage shape. Applied to three human cancer cohorts from the Cancer Genome Atlas (TCGA), chosen based on tissue morphology and anatomic site, we identified genes, the "offonome" near the detection limit, consistently or occasionally off across samples. Genes in the offonome spectrum proved useful for supervised and unsupervised applications, including characterizing oncogenic pathways, and identifying rare populations of cells in bulk tissue. Interrogating the offonome is relevant to bulk tumor analyses like TCGA, potentially expediting gene investigation in low-input situations like single cell RNA-seq.

Humans

1-Mb resolution array-based comparative genomic hybridization using a BAC clone set optimized for cancer gene analysis.

Array-based comparative genomic hybridization (aCGH) is a recently developed tool for genome-wide determination of DNA copy number alterations. This technology has tremendous potential for disease-gene discovery in cancer and developmental disorders as well as numerous other applications. However, widespread utilization of a CGH has been limited by the lack of well characterized, high-resolution clone sets optimized for consistent performance in aCGH assays and specifically designed analytic software. We have assembled a set of approximately 4100 publicly available human bacterial artificial chromosome (BAC) clones evenly spaced at approximately 1-Mb resolution across the genome, which includes direct coverage of approximately 400 known cancer genes. This aCGH-optimized clone set was compiled from five existing sets, experimentally refined, and supplemented for higher resolution and enhancing mapping capabilities. This clone set is associated with a public online resource containing detailed clone mapping data, protocols for the construction and use of arrays, and a suite of analytical software tools designed specifically for aCGH analysis. These resources should greatly facilitate the use of aCGH in gene discovery.

Cell Line, Tumor

Clinical and genetic features of Ph-negative myeloproliferative neoplasms with dual-driver gene positivity.

OBJECTIVES: To investigate the clinical laboratory characteristics and gene mutation features of dual-driver gene positivity in patients with Philadelphia chromosome-negative myeloproliferative neoplasm (Ph-negative MPN). METHODS: We conducted a retrospective analysis of clinical data and genetic test results from 203 newly diagnosed patients with Ph-negative MPN. Of these, 194 had single-driver gene positivity and 9 had dual-driver gene positivity. High-throughput sequencing was used to detect mutations in JAK2, CALR, and MPL. Clinical characteristics and gene mutation profiles were compared between the two patient groups. RESULTS: The incidence of dual-driver gene positivity was 4.4% (9/203), with the most common combinations being JAK2 with CALR (4 patients) and JAK2 with MPL (4 patients). Compared with the single-driver group, the dual-driver group had a significantly higher risk of bleeding [4.1% (8/194) vs. 33.3% (3/9), P = 0.008] and a higher proportion of uncommon mutations [3.6% (7/194) vs. 33.3% (3/9), P = 0.006]. No statistically significant differences were observed between the two groups regarding age, thrombosis incidence, splenomegaly, or routine blood test indicators. During follow-up, 1 patient in the dual-driver group died from cerebrovascular disease. No leukaemia transformation or disease-related deaths occurred among the remaining patients. DISCUSSION: The increased bleeding risk in dual-driver patients may be related to a higher proportion of CALR mutations, elevated platelet counts, and higher variant allele frequencies, though these findings require validation in larger cohorts due to the small sample size. The higher prevalence of uncommon mutations suggests a more complex mutational landscape in this subgroup. CONCLUSION: Patients with Ph-negative MPN and dual-driver gene positivity may have a higher risk of bleeding and a more complex gene mutation profile.

Humans

Fecal immunochemical tests from population-based colorectal cancer screening programs support prospective microbiome cohorts.

BACKGROUND: Large, prospective cohorts are needed to research the gut microbiome's role in colorectal cancer (CRC) risk. We evaluated the gut microbiome leveraging residual fecal immunochemical tests (FIT) from a CRC screening program in Turin, Italy, and conducted one of the largest population-based case-control studies across the adenoma-carcinoma sequence to date. METHODS: We extracted DNA from residual FIT stool, used whole-genome shotgun sequencing, and included those with CRC (N = 44), advanced adenomas (N = 269), early adenomas (N = 134), and FIT-negative controls (N = 478). Alpha diversity, beta diversity, and species, gene, and pathway relative abundances were estimated. Multivariable logistic regression models were used to estimate associations of these metrics with colorectal neoplasms. RESULTS: Alpha diversity was mostly inversely associated with colorectal neoplasms, particularly early adenomas (OR: 0.45, 95% CI: 0.25-0.80; P = 0.01). Presence of oral pathogens, including Parvimonas micra, was associated with higher odds of CRC. Furthermore, Escherichia coli and Bacteroides fragilis were strongly associated with higher odds of all colorectal neoplasms. Several genes and pathways were associated with colorectal neoplasms. CONCLUSIONS: Our findings align with smaller studies of the gut microbiome and colorectal neoplasms, supporting that CRC screening programs provide opportunities to prospectively study the gut microbiome's association with cancer risk in large populations.

Humans

Rat hepatoma cells nucleolar DNA. II. A possible model of nucleolar DNA organisation.

A model of nucleolar DNA organization has been established. Three clearly defined main components are found in ascites hepatoma cell nucleolar DNA by CsCl gradient analysis. A linear arrangement for nucleolar DNA and a model of DNA organization in the neighbourhood of a set of ribosomal genes, which may play a fundamental role in the elaboration of nucleolar chromatin tertiary structure, are presented.

Animals

Genetics of retinoblastoma.

Retinoblastoma may be due to (1) a somatic mutation, which is not hereditary, (2) a germinal mutation, which is dominantly inherited, and (3) a deletion of the long arm of chromosome 13. In unilateral cases of retinoblastoma, the risk for the offspring is 5-6%, as 10-15% of these cases are due to a germinal mutation. In all the bilateral cases and in the unilateral hereditary cases, the risk for the offspring or the sibs is 40-50% depending on the penetrance of the gene.

Chromosome Deletion

A very large repeating unit of mouse DNA containing the 18S, 28S and 5.8S rRNA genes.

The organization of the 18S, 28S and 5.8S rRNA genes in the mouse has been elucidated by mapping with restriction endonucleases Eco RI, Hind III and Bam HI. Ribosomal DNA fragments were detected in electrophoretically fractionated digests of total nuclear DNA by in situ hybridization with radioiodinated rRNAs or with complementary RNA synthesized directly on rRNA templates. A map of the rDNA which includes 13 restriction sites was constructed from the sizes of rDNA fragments and their labeling by different probes The map indicates that the rRNA genes lie within remarkably large units of reiterated DNA, at least 44,000 base pairs long. At least two, and possibly four, classes of repeating unit can be distinguished, the heterogeneity probably residing in the very large nontranscribed spacer region. The 5.8S rRNA gene lies in the transcribed region between the 18S and 28S genes.

Animals

Overexpression of a subset of long intergenic noncoding RNAs in uterine serous carcinoma predicts poor prognosis.

The evaluation and prediction of uterine serous carcinoma (USC), a type of endometrial cancer that is more severe than endometrioid adenocarcinoma, remain challenging. Long noncoding RNAs (lncRNAs) are frequently dysregulated in human cancers. This study assessed the expression patterns and prognostic values of long intergenic noncoding RNAs (lincRNAs) in USC. RNA sequencing, copy number variation (CNV), and clinical data from The Cancer Genome Atlas were used to investigate various lncRNAs in endometrial cancer. LincRNAs, a major subclass of lncRNAs, exhibit specific expression patterns modulated by CNVs and act as predictors of poor prognosis, survival, and recurrence in USC. Functional analyses were conducted to investigate the roles of lncRNAs in USC. Finally, the expression of these lincRNAs was verified in 32 pairs of USCs collected from the hospital over 3 years. A series of lincRNAs were found to be specifically expressed in USC compared with other lncRNAs and regulated by CNV. Moreover, these specific upregulated lincRNAs, particularly ENSG00000281406, ENSG00000226791, ENSG00000269903, and ENSG00000204277, demonstrated poor prognoses for survival and recurrence in USC. Functionally, our analysis showed that ENSG00000281406 positively correlated with the Wnt signaling pathway, whereas ENSG00000226791, ENSG00000269903, and ENSG00000204277 negatively correlated with the T-cell receptor signaling pathway. Importantly, we confirmed that ENSG00000204277 negatively correlated with CD8+ T-cell immune infiltration in USC. Our results highlight that these lincRNAs can serve as new biomarkers for the prognostic prediction of USC. In particular, ENSG00000204277 may be used as a therapeutic target for USC.

Humans

Genetic problems in tumours of the gastrointestinal tract.

The role of heredity in the production of gastrointestinal tumours is reviewed. The rare forms showing Mendelian inheritance are described, with special reference to oesophageal cancer and to familial polyposis of the colon. The high risks in these disorders are contrasted with the generally low risks to family members for the common cancers of the digestive tract. The part played by genetic factors in production of the premalignant state is critically discussed, with emphasis on gastric and hepatic cancer. The various experimental genetic approaches to the causation and early detection of cancer are outlined, and it is concluded that both genetic and environmental factors should be considered together when the etiology is being investigated.

Africa

NR3C1 Modulates Wnt Signalling to Influence the Invasiveness and Immune Features of Nonfunctioning Invasive Pituitary Adenomas.

Pituitary adenomas (PAs) are common intracranial tumours, and invasiveness in nonfunctioning invasive pituitary adenomas (NIPAs) predicts poor prognosis. The molecular mechanisms driving this phenotype remain unclear. This study explored the role of nuclear receptor subfamily 3 group C member 1 (NR3C1) in NIPA invasiveness and its regulation of Wnt signalling. mRNA expression profiles of 32 PA samples were generated by RNA-seq, and proteomic data from 19 samples were obtained by mass spectrometry. Immune-related differentially expressed genes (DEGs) were retrieved from GeneCards. Weighted gene coexpression network analysis identified modules and hub genes linked to invasiveness, while machine learning methods (support vector machine, LASSO, random forest) prioritised key genes. Gene set enrichment analysis (GSEA) assessed pathways associated with candidate gene expression. NR3C1 expression and function were validated by immunohistochemistry, Western blotting and invasion assays. Integration of transcriptomic, proteomic and immune-related datasets yielded 11 overlapping genes, with NR3C1 emerging as the top candidate. NR3C1 was significantly upregulated in NIPAs and demonstrated good discriminatory power by ROC analysis. GSEA associated high NR3C1 expression with Wnt pathway activation. Functional experiments confirmed that NR3C1 overexpression enhances the invasive capacity of PA cells. NR3C1 promotes the invasive phenotype of NIPAs by activating Wnt signalling. These findings suggest NR3C1 as a potential biomarker and therapeutic target for invasive pituitary adenomas.

Humans