Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal human malignancies, with an overall 5-year survival rate of <5%. Genetic analysis of PDAC patient samples has shown that specific disease-associated mutations are correlated with histologically defined stages of neoplastic progression in the ductal epithelium. Activating mutations in KRAS are almost uniformly present in early-stage disease, with subsequent inactivating mutations in p16(INK4A), p53, and SMAD4 occurring in more advanced lesions. In this study, we have tested whether the loss of Smad4 would cooperate with an activating Kras(G12D) mutation to promote progression to PDAC using the Pdx1-Cre transgenic system to activate Kras(G12D) and delete Smad4 in all pancreatic lineages including the ductal epithelium. Analysis of double-mutant mice showed that loss of Smad4 significantly accelerated the progression of pancreatic intraepithelial neoplasias (mPanIN) and promoted a high incidence of intraductal papillary mucinous neoplasia and active fibrosis compared with Pdx1-Cre;Kras(G12D) or Pdx1-Cre;Smad4(lox/lox) mice. Occasionally, double-mutant mice progressed to locally invasive PDAC with little evidence of metastases by 6 months of age and without the detectable loss of p53 or p16(Ink4A) expression or function. The loss of Smad4 only seemed to promote disease progression in the presence of the activated Kras(G12D) allele because we observed no abnormal pathology within the pancreata of 23 Pdx1-Cre;Smad4(lox/lox) animals that were analyzed up to 8 months of age. This indicates that Smad4 is dispensable for normal pancreatic development but is critical for at least partial suppression of multiple Kras(G12D)-dependent disease-associated phenotypes.
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PMID:Inactivation of Smad4 accelerates Kras(G12D)-mediated pancreatic neoplasia. 1780 24

Malignant melanoma originates in melanocytes, the pigment-producing cells of the skin and eye, and is one of the most deadly human cancers with no effective cure for metastatic disease. Like many other cancers, melanoma has both environmental and genetic components. For more than 20 years, the melanoma genome has been subject to extensive scrutiny, which has led to the identification of several genes that contribute to melanoma genesis and progression. Three molecular pathways have been found to be nearly invariably dysregulated in melanocytic tumors, including the RAS-RAF-MEK-ERK pathway (through mutation of BRAF, NRAS or KIT), the p16 INK4A-CDK4-RB pathway (through mutation of INK4A or CDK4) and the ARF-p53 pathway (through mutation of ARF or TP53). Less frequently targeted pathways include the PI3K-AKT pathway (through mutation of NRAS, PTEN or PIK3CA) and the canonical Wnt signaling pathway (through mutation of CTNNB1 or APC). Beyond the specific and well-characterized genetic events leading to activation of proto-oncogenes or inactivation of tumor suppressor genes in these pathways, systematic high-resolution genomic analysis of melanoma specimens has revealed recurrent DNA copy number aberrations as well as perturbations of DNA methylation patterns. Melanoma provides one of the best examples of how genomic analysis can lead to a better understanding of tumor biology. We review current knowledge of the genes involved in the development of melanoma and the molecular pathways in which these genes operate.
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PMID:The genome and epigenome of malignant melanoma. 1804 49

Epithelial ovarian cancers may represent secondary manifestations of occult extraovarian carcinomas. Such tumors may be misdiagnosed as primary ovarian carcinomas clinically and pathologically. In a recent study, several cases of cervical cancer metastases with primary manifestation as mucinous or endometrioid ovarian carcinomas were described. In all cases, human papillomavirus (HPV) DNA and diffuse p16 immunostaining were detected in the ovarian tumor tissues. To estimate the frequency of occult metastatic endocervical adenocarcinomas in a series of mucinous or endometrioid ovarian carcinomas, 24 ovarian cancers with mucinous and 50 with endometrioid differentiation from the Arbeitsgemeinschaft Gynaekologische Onkologie OVAR-3 database were analyzed for HPV and p16 positivity. The p16 immunostaining was performed using the p16 histology kit (Dako, Glostrup, Denmark), and both nuclear and cytoplasmic staining results were considered positive. Human papillomavirus polymerase chain reaction analysis was performed using 2 consensus primer systems (GP5/GP6 and PGMY09/11) and HPV-16- and HPV-18-specific primers from the L1 and the E6 regions. Six (8%) of 74 tumors were p16-negative, 13 (18%) of 74 showed single positive cells, 28 (38%) of 74 showed focal homogeneous staining, and 27 (36%) of 74 showed complete diffuse staining. In several independent amplifications of different regions of the HPV genome, none of the 73 tumors available for analysis showed the presence of HPV DNA. No ovarian metastases of endocervical adenocarcinomas were found among mucinous and endometrioid adenocarcinomas from a large chemotherapy trial of advanced stage ovarian carcinomas. The p16 staining detected in many primary ovarian adenocarcinomas in the present series seems independent from HPV oncogene activity.
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PMID:No metastatic cervical adenocarcinomas in a series of p16INK4a-positive mucinous or endometrioid advanced ovarian carcinomas: an analysis of the AGO Ovarian Cancer Study Group. 1815 69

The Wild-type p53-induced phosphatase 1, Wip1 (or PPM1D), is unusual in that it is a serine/threonine phosphatase with oncogenic activity. A member of the type 2C phosphatases (PP2Cdelta), Wip1 has been shown to be amplified and overexpressed in multiple human cancer types, including breast and ovarian carcinomas. In rodent primary fibroblast transformation assays, Wip1 cooperates with known oncogenes to induce transformed foci. The recent identification of target proteins that are dephosphorylated by Wip1 has provided mechanistic insights into its oncogenic functions. Wip1 acts as a homeostatic regulator of the DNA damage response by dephosphorylating proteins that are substrates of both ATM and ATR, important DNA damage sensor kinases. Wip1 also suppresses the activity of multiple tumor suppressors, including p53, ATM, p16(INK4a) and ARF. We present evidence that the suppression of p53, p38 MAP kinase, and ATM/ATR signaling pathways by Wip1 are important components of its oncogenicity when it is amplified and overexpressed in human cancers.
Cancer Metastasis Rev 2008 Jun
PMID:The type 2C phosphatase Wip1: an oncogenic regulator of tumor suppressor and DNA damage response pathways. 1826 45

Recent evidence demonstrates that senescence acts as a barrier to tumorigenesis in response to oncogene activation. Using a mouse model of breast cancer, we tested the importance of the senescence response in solid cancer and identified genetic pathways regulating this response. Mammary expression of activated Ras led to the formation of senescent cellular foci in a majority of mice. Deletion of the p19(ARF), p53, or p21(WAF1) tumor suppressors but not p16(INK4a) prevented senescence and permitted tumorigenesis. Id1 has been implicated in the control of senescence in vitro, and elevated expression of Id1 is found in a number of solid cancers, so we tested whether overexpression of Id1 regulates senescence in vivo. Although overexpression of Id1 in the mammary epithelium was not sufficient for tumorigenesis, mice with expression of both Id1 and activated Ras developed metastatic cancer. These tumors expressed high levels of p19(Arf), p53, and p21(Waf1), demonstrating that Id1 acts to make cells refractory to p21(Waf1)-dependent cell cycle arrest. Inactivation of the conditional Id1 allele in established tumors led to widespread senescence within 10 days, tumor growth arrest, and tumor regression in 40% of mice. Mice in which Id1 expression was inactivated also exhibited greatly reduced pulmonary metastatic load. These data demonstrate that established tumors remain sensitive to senescence and that Id1 may be a valuable target for therapy.
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PMID:Id1 cooperates with oncogenic Ras to induce metastatic mammary carcinoma by subversion of the cellular senescence response. 1837 7

Functional inactivation of the tumour suppressor protein p16(INK4a) constitutes a key event in the multistep process of pancreatic ductal cell transformation. However, the significance of p16 inactivation for complex and tissue-specific aspects of pancreatic cancer progression, such as angiogenesis and metastasis, is less understood. Here, we inducibly re-expressed p16 in vivo in an orthotopic model of pancreatic cancer and examined the impact on these clinically relevant aspects of pancreatic cancer tumour biology. Consistent with previous work in subcutaneous xenograft models, we found p16 capable of reducing primary tumour growth. In addition, p16 restitution resulted in a marked reduction of tumour angiogenesis, largely accounted for by a p16-dependent inhibition of lymphangiogenesis. In excellent agreement with the antilymphangiogenic effect, re-expression of p16 almost completely prevented lymph node metastases of MiaPaca-2 pancreatic tumours. To our knowledge, this is the first report that experimentally links the tumour suppressor p16 to the process of lymphangiogenesis.
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PMID:Inducible re-expression of p16 in an orthotopic mouse model of pancreatic cancer inhibits lymphangiogenesis and lymphatic metastasis. 1857 84

Chondrosarcomas are highly resistant to conventional radiation and chemotherapy, and surgical removal is the only option for curative treatment. Consequently, there is nothing to offer patients with inoperable tumours and metastatic disease. The aim of this study is to investigate genes involved in cell cycle control: CDK4, CDKN2A/p16, cyclin D1, p21, p53, MDM2 and c-MYC, which may point towards new therapeutic strategies. The pRb pathway was targeted using CDKN2A/p16 overexpressing vectors and shRNA against CDK4 in chondrosarcoma cell lines OUMS27, SW1353, and CH2879. Cell survival and proliferation were assessed. CDK4, MDM2 and c-MYC expression levels were investigated by qPCR and immunohistochemistry (IHC) in 34 fresh frozen and 90 FFPE samples of enchondroma and chondrosarcoma patients. On a subset of 29 high-grade chondrosarcomas IHC for cyclin D1, p21 and p53 was performed. The overexpression of CDKN2A/p16 and knockdown of CDK4 by shRNA in OUMS27, SW1353 and CH2879 resulted in a significant decrease in cell viability and proliferation and a decreased ability to form colonies in vitro. Expression of CDK4 and MDM2 was associated with high-grade chondrosarcoma both at the mRNA and protein level. Combining these results with the expression of cyclin D1 and the previously shown loss of CDKN2A/p16 expression show that the majority (96%; 28/29) of high-grade chondrosarcomas contain alterations in the pRb pathway. This suggests a role for the use of CDK4 inhibitors as a treatment of metastatic or inoperable high-grade chondrosarcoma.
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PMID:Central chondrosarcoma progression is associated with pRb pathway alterations: CDK4 down-regulation and p16 overexpression inhibit cell growth in vitro. 1862 51

We have investigated the frequency of methylation of several tumour suppressor genes in uveal melanoma. As the loss of one copy of chromosome 3 (monosomy 3), which is found in about half of these tumours, is tightly associated with metastatic disease, a special emphasis was laid on genes located on this chromosome, including the fragile histidine triad (FHIT), von Hippel-Lindau (VHL), beta-catenin (CTNNB1), activated leukocyte cell adhesion molecule (ALCAM) and retinoic acid receptor-beta2 (RARB) genes. In addition, the methylation patterns of the CpG-rich regions 5' of the E-cadherin (CDH1), p16/cyclin-dependent kinase inhibitor 2 A (CDKN2A) and retinoblastoma (RB1) genes were analysed by bisulphite genomic sequencing or methylation-specific PCR (MSP). Furthermore, the SNRPN and D15S63 loci, which are located in the imprinted region of chromosome 15, were included in the study. Aberrant methylation was detected in nine of 40 tumours analysed: The imprinted SNRPN and D15S63 loci were hypermethylated in three tumours, all of which retained both copies of chromosome 3. Methylated RARB alleles were detected in three tumours, whereas in three other tumours CDKN2A was found to be methylated. As we did not find RARB and CDKN2A preferentially methylated in tumours with monosomy 3, which is a significant predictor of metastatic disease, we suggest that these genes may play a causative role in the formation of uveal melanoma but not in the development of metastases.
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PMID:Methylation analysis of several tumour suppressor genes shows a low frequency of methylation of CDKN2A and RARB in uveal melanomas. 1862 84

Anal squamous cell carcinoma and its precursor lesions are increasing in incidence in the United States and Europe. This trend predates human immunodeficiency virus/acquired immune deficiency syndrome and has been associated with persistent high-risk human papilloma virus (HPV) genotype infection, previous lower genital tract dysplasia/carcinoma, high frequency anoreceptive intercourse, heavy cigarette smoking, immunosuppression in solid organ transplant and immune disorders, and human immunodeficiency virus seropositivity. Screening protocols for at-risk patients are under active investigation and pathologists are often asked to assess anal canal and perianal biopsies for the presence of dysplasia and/or invasive carcinoma. Because underdiagnosis and overdiagnosis of anal cancer and precancer may lead to inappropriate treatment, it is important for the pathologist to be aware of current screening strategies, specific risk lesions, and the role of pathology in initial diagnosis and evaluation of anal biopsy and/or resection specimens. Standardized histologic criteria and uniform terminology should be used for reporting all anal canal and perianal squamous intraepithelial lesions. HPV subtyping, anal cytology, and recently identified biomarkers, such as p16 and Becton Dickinson ProEx C may provide additional information in problematic cases, but it is important to be aware of the limitations of these assays. HPV has been linked to all the major histologic subtypes of anal carcinoma (eg, basaloid, cloacogenic, transitional, etc.) and this association is strongest for anal canal lesions. With the possible exception of the microcystic pattern, histologic subtype does not seem to predict prognosis; and anal squamous cell carcinomas should be classified as either keratinizing or nonkeratinizing. Poorly differentiated squamous cell carcinomas have a worse prognosis and should be distinguished from poorly differentiated adenocarcinoma, melanoma, and neuroendocrine tumors. Very well differentiated squamous cell carcinoma with pushing margins (so-called giant condyloma of Buschke and Lowenstein) should be classified as verrucous carcinoma; this tumor shows aggressive local infiltration but does not metastasize. As all anal condylomata may harbor foci of high-grade dysplasia or invasive carcinoma, careful sectioning and complete histologic examination is required.
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PMID:Diagnostic problems in anal pathology. 1872

Gastrointestinal stromal tumors (GISTs) are characterized by alterations in genes involved in cell cycle regulation. Although p16 (INK4A) have been extensively investigated in GISTs, there are still discrepancies regarding its prognostic value. Therefore, we evaluated the clinical occurrence, diagnostic and prognostic value of p16 staining in GIST. One hundred one patients (54 women and 47 men) with a mean age of 64.1 years (range, 17-94 years) were surgically treated for a GIST within a 10-year period. Of these patients, 28 (28%) were affected by metastases (mean follow-up, 4.5 years). In 36 patients (36%), GIST occurred coincidentally with other malignancies. Expression of c-kit was confirmed in 97 GIST patients (96%). In patients with high-risk GIST, the expression of p16 expression was highly predictive for poor prognosis, i.e., the development of recurrence or metastases (P = .006) and poor survival (P = .004). In addition, the expression of p16 was highly predictive for reduction of the survival in patients who were affected by metastases or recurrence (P = .041). The disease-specific and disease-free 1-, 3-, and 5-year survival rate was 96%, 90%, and 85% and 81%, 77%, and 72%, respectively. Primary tumor state, tumor size, and high-risk classification were confirmed as relevant predictors for unfavorable prognosis in GIST (P < .001). Our results indicate that in high-risk GIST and in patients with recurrence or metastases, the expression of p16 is highly predictive for poor outcome. Thus, in addition to high-risk classification, p16 expression might be an indicator for "very high risk GIST."
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PMID:p16 expression differentiates high-risk gastrointestinal stromal tumor and predicts poor outcome. 1881 51


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