Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA.
Transforming growth factor  (TGF-) initiates multiple signal pathways and activates many downstream kinases. Here, we determined that TGF-1 bound cell surface hyaluronidase Hyal-2 on microvilli in type II TGF- receptor-deficient HCT116 cells, as determined by immunoelectron microscopy. This binding resulted in recruitment of proapoptotic WOX1 (also named WWOX or FOR) and formation of Hyal-2⅐WOX1 complexes for relocation to the nuclei. TGF-1 strengthened the binding of the catalytic domain of Hyal-2 with the N-terminal Tyr-33-phosphorylated WW domain of WOX1, as determined by time lapse fluorescence resonance energy transfer analysis in live cells, co-immunoprecipitation, and yeast twohybrid domain/domain mapping. In promoter activation assay, ectopic WOX1 or Hyal-2 alone increased the promoter activity driven by Smad. In combination, WOX1 and Hyal-2 dramatically enhanced the promoter activation (8 -9-fold increases), which subsequently led to cell death (>95% of promoter-activated cells). TGF-1 supports L929 fibroblast growth. In contrast, transiently overexpressed WOX1 and Hyal-2 sensitized L929 to TGF-1-induced apoptosis. Together, TGF-1 invokes a novel signaling by engaging cell surface Hyal-2 and recruiting WOX1 for regulating the activation of Smad-driven promoter, thereby controlling cell growth and death. Transforming growth factor  (TGF-)4 plays a dual role in cell growth and tumorigenesis (1, 2). TGF- inhibits mammary epithelial cell growth. In contrast, invasive cancer cells frequently overproduce TGF- to promote growth and metastasis (1, 2). The underlying mechanism is largely unknown. TGF- induces the development of metastatic phenotypes, i.e. stimulation of epithelial-mesenchymal transitions in cancerous mammary epithelial cells (1, 2). These cells are normally devoid of functional type II TGF- receptor (TRII), suggesting that TGF- binds to an alternative receptor for signaling.Hyaluronan is the major components of pericellular coat and plays a key role in affecting cell morphology, communication, and behavior (3-5). Up-regulation of hyaluronan and hyaluronidases Hyal-1, Hyal-2, and PH-20 is associated with cancer metastasis (3-5). Hyaluronidases counteract the activity of TGF-1 (6 -8). TGF-1 suppresses the proliferation of normal epithelial cells, whereas PH-20 blocks the TGF-1 effect (6). Hyal-1 and Hyal-2 enhance the cytotoxic function of TNF and block TGF-1-mediated protection of murine L929 fibroblasts from TNF cytotoxicity (6 -8).Hyaluronidases PH-20, Hyal-1, and Hyal-2 induce the expression of tumor suppressor WW domain-containing oxidoreductase, known as WWOX, FOR or WOX1 (8 -11). Human WWOX gene is located on a chromosomal fragile site 16q23 and encodes WWOX/FOR/WOX1 and isoforms (9, 10, 12-16). The full-length 46-kDa WOX1 possesses two N-terminal WW domains (containing conserved tryptophan residues), a nuclear localization sequence between the WW domains, and a C-terminal short chain alcohol dehydrogenase/reductase domain. Numerous exogenous stimuli, including sex stero...
Aristolochic acid (AA), a natural product of Aristolochia plants found in herbal remedies and health supplements, is a group 1 carcinogen that can cause nephrotoxicity and upper urinary tract urothelial cell carcinoma (UTUC). Whole-genome and exome analysis of nine AA-associated UTUCs revealed a strikingly high somatic mutation rate (150 mutations/Mb), exceeding smoking-associated lung cancer (8 mutations/Mb) and ultraviolet radiation-associated melanoma (111 mutations/Mb). The AA-UTUC mutational signature was characterized by A:T to T:A transversions at the sequence motif A[C|T]AGG, located primarily on nontranscribed strands. AA-induced mutations were also significantly enriched at splice sites, suggesting a role for splice-site mutations in UTUC pathogenesis. RNA sequencing of AA-UTUC confirmed a general up-regulation of nonsense-mediated decay machinery components and aberrant splicing events associated with splice-site mutations. We observed a high frequency of somatic mutations in chromatin modifiers, particularly KDM6A, in AA-UTUC, demonstrated the sufficiency of AA to induce renal dysplasia in mice, and reproduced the AA mutational signature in experimentally treated human renal tubular cells. Finally, exploring other malignancies that were not known to be associated with AA, we screened 93 hepatocellular carcinoma genomes/exomes and identified AA-like mutational signatures in 11. Our study highlights an unusual genome-wide AA mutational signature and the potential use of mutation signatures as "molecular fingerprints" for interrogating high-throughput cancer genome data to infer previous carcinogen exposures.
BACKGROUND & AIMS Gastric cancer (GC) is a heterogeneous disease comprising multiple subtypes that each have distinct biological properties and effects in patients. We sought to identify new, intrinsic subtypes of GC by gene expression analysis of a large panel of GC cell lines. We tested if these subtypes might be associated with differences patient survival times and responses to various standard-of-care cytotoxic drugs. METHODS We analyzed gene expression profiles for 37 GC cell lines to identify intrinsic GC subtypes. These subtypes were validated in primary tumors from 521 patients in 4 independent cohorts, where the subtypes were determined by either expression profiling or subtype-specific immunohistochemical markers (LGALS4, CDH17). In vitro sensitivity to 3 chemotherapy drugs (5-FU, cisplatin, oxaliplatin) was also assessed. RESULTS Unsupervised cell line analysis identified 2 major intrinsic genomic subtypes (G-INT and G-DIF), that had distinct patterns of gene expression. The intrinsic subtypes, but not subtypes based on Lauren’s histopathologic classification, were prognostic of survival, based on univariate and multivariate analysis in multiple patient cohorts. The G-INT cell lines were significantly more sensitive to 5-FU and oxaliplatin, but more resistant to cisplatin, than the G-DIF cell lines. In patients, intrinsic subtypes were associated with survival time following adjuvant, 5-FU based therapy. CONCLUSIONS Intrinsic subtypes of GC, based on distinct patterns of expression, are associated with patient survival and response to chemotherapy. Classification of GC based on intrinsic subtypes might be used to determine prognosis and customize therapy.
IntroductionZinc finger-like protein that regulates apoptosis (Zfra) is a naturally occurring 31-amino-acid protein. Synthetic peptides Zfra1–31 and Zfra4–10 are known to effectively block the growth of many types of cancer cells.MethodsTen-month-old triple-transgenic (3×Tg) mice for Alzheimer's disease (AD) received synthetic Zfra peptides via tail vein injections, followed by examining restoration of memory deficits.ResultsZfra significantly downregulated TRAPPC6AΔ, SH3GLB2, tau, and amyloid β (Αβ) aggregates in the brains of 3×Tg mice and effectively restored their memory capabilities. Zfra inhibited melanoma-induced neuronal death in the hippocampus and plaque formation in the cortex. Mechanistically, Zfra blocked the aggregation of amyloid β 42 and many serine-containing peptides in vitro, suppressed tumor necrosis factor–mediated NF-κB activation, and bound cytosolic proteins for accelerating their degradation in ubiquitin/proteasome-independent manner.DiscussionZfra peptides exhibit a strong efficacy in blocking tau aggregation and amyloid Αβ formation and restore memory deficits in 3×Tg mice, suggesting its potential for treatment of AD.
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