Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We performed the immunohistochemical staining for six G1 check point cell cycle proteins to study their expression patterns and roles in the gastric carcinogenesis. We studied 76 cases of paraffin blocks that included the sections of 18 tubular adenomas (TA), 38 early gastric carcinomas (EGC) (20 cases of mucosal type, nine cases of submucosal type with no nodal metastasis, nine cases of submucosal type with nodal metastasis), 20 advanced gastric carcinomas (AGC) (ten cases with no nodal metastasis, ten cases with nodal metastasis). We found that abnormal expression of p16 and p27 increased with the progression of tubular adenomas to advanced gastric cancers. Inverse relationship between pRb and p16 proteins was found in a small portion of the gastric tumors. Expressions of pRb and cdk4 were consistently high in benign and malignant gastric tumors. Expression of cyclin D1 and cyclin E rather decreased with the tumor progression. In conclusion, losses of p16 and p27 seem to play a significant role during the gastric carcinogenesis, and the G1 checkpoint cell cycle proteins such as pRb, cdk4, cyclin D1, and cyclin E variably participate in the gastric carcinogenesis and metastasis by the mechanisms which are yet unknown; thus, further studies need to be performed to elucidate the mechanisms.
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PMID:Loss of p16 and p27 is associated with progression of human gastric cancer. 1077 41

p27(Kip1) is a cyclin-dependent kinase inhibitor that negatively regulates cell proliferation. This study was designed to evaluate the roles of p27(Kip1) in gallbladder carcinogenesis and the prognostic value of p27(Kip1) in patients with gallbladder carcinoma. p27(Kip1) expression was examined immunohistochemically in surgically resected specimens of 8 normal epithelia, 8 adenomyomatosis lesions, 6 precancerous adenomas, and 37 carcinomas of the gallbladder. Decreased p27(Kip1) expression (<50% nuclear staining) was observed in 16 of the 37 (43%) gallbladder carcinomas, but not in any specimen of normal epithelium, adenomyomatosis, or adenoma. The fact that all of the adenomas showed normal p27(Kip1) expression suggests that decreased p27(Kip1) expression is probably not an early event in gallbladder carcinogenesis. Decreased p27(Kip1) expression was significantly associated with less marked tumor cell differentiation (P =.017), lymphatic invasion (P =.046), lymph node metastasis (P =.007), and advanced TNM stage (stage IV vs. stage I, P =.026; stage IV vs. stage II, P =.005). This suggests that down-regulation of p27(Kip1) expression is a late event in gallbladder carcinogenesis, possibly promoting tumor progression and metastasis. Kaplan-Meier curves showed that decreased p27(Kip1) expression was significantly associated with shorter overall survival (P =.001) in patients with gallbladder carcinomas who had undergone radical surgery. Cox's proportional hazards model revealed decreased p27(Kip1) expression to be an independent predictor for death (P =.034; risk ratio, 3.9; 95% confidence interval, 1.1-13.7). In conclusion, decreased p27(Kip1) expression significantly correlates with tumor progression and predicts poor prognosis in gallbladder carcinomas.
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PMID:p27(Kip1) expression in normal epithelia, precancerous lesions, and carcinomas of the gallbladder: association with cancer progression and prognosis. 1079 81

The biological activity of two novel 14-epi-analogues of 1,25(OH)2D3, 19-nor-14-epi-23-yne-1,25(OH)2D3 (TX 522) and 19-nor-14,20-bisepi-23-yne-1,25(OH)2D3 (TX 527), is described. Both analogues were at least 10 times more potent than 1,25(OH)2D3 in inhibiting in vitro cell proliferation and had much lower in vivo calcemic effects than 1,25(OH)2D3. Treatment with 1,25(OH)2D3, TX 522, or TX 527 in vitro was accompanied by an accumulation of cells in the G1 phase of the cell cycle. Protein levels of cyclin C and cyclin D1 in in vitro cultures of MCF-7 cells were down-regulated to 50 and 30%, respectively, of control levels at 72 and 120 h after stimulation. Protein levels of p21 and p27 at 72 h were significantly enhanced by 1,25(OH)2D3 and TX 522 but surprisingly not by TX 527. The inability of TX 527 to up-regulate p21 seemed to be cell type specific because p21 was induced in other cell types. Diminished phosphorylation of the retinoblastoma protein after treatment with 1,25(OH)2D3, TX 522, or TX 527 may ultimately contribute to the growth inhibition caused by these compounds. According to the data presented, the induction of apoptosis seemed not to be a major mechanism responsible for the growth-inhibitory effect of 1,25(OH)2D3 and analogues. Both 14-epianalogues significantly retarded tumor progression (40% reduced compared with control mice) in an in vivo model of MCF-7 breast cancer cells established in nude mice. In conclusion, these novel analogues have the eligible profile to be tested as therapeutic agents for the treatment of hyperproliferative diseases such as breast cancer.
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PMID:Two novel 14-Epi-analogues of 1,25-dihydroxyvitamin D3 inhibit the growth of human breast cancer cells in vitro and in vivo. 1082 40

The PTEN tumor suppressor gene is frequently inactivated in human prostate cancers, particularly in more advanced cancers, suggesting that the AKT/protein kinase B (PKB) kinase, which is negatively regulated by PTEN, may be involved in human prostate cancer progression. We now show that AKT activation and activity are markedly increased in androgen-independent, prostate-specific antigen-positive prostate cancer cells (LNAI cells) established from xenograft tumors of the androgen-dependent LNCaP cell line. These LNAI cells show increased expression of integrin-linked kinase, which is putatively responsible for AKT activation/Ser-473 phosphorylation, as well as for increased phosphorylation of the AKT target protein, BAD. Furthermore, expression of the p27(Kip1) cell cycle regulator was diminished in LNAI cells, consistent with the notion that AKT directly inhibits AFX/Forkhead-mediated transcription of p27(Kip1). To assess directly the impact of increased AKT activity on prostate cancer progression, an activated hAKT1 mutant was overexpressed in LNCaP cells, resulting in a 6-fold increase in xenograft tumor growth. Like LNAI cells, these transfectants showed dramatically reduced p27(Kip1) expression. Together, these data implicate increased AKT activity in prostate tumor progression and androgen independence and suggest that diminished p27(Kip1) expression, which has been repeatedly associated with prostate cancer progression, may be a consequence of increased AKT activity.
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PMID:Increased AKT activity contributes to prostate cancer progression by dramatically accelerating prostate tumor growth and diminishing p27Kip1 expression. 1082 91

p27(Kip1) (p27), a cyclin-dependent kinase inhibitor, has an important role in the progression of cells from G(1) into S phase of the cell cycle. p27 may act as a tumor suppressor, and several reports suggest that loss of its expression in breast carcinoma is related to tumor progression and poor prognosis. We evaluated p27 immunohistochemical expression in 512 consecutive cases of breast carcinoma with 9 years of median-term follow-up. p27 expression was heterogeneous and frequently less intense than in normal cells. Low p27 expression (<50% of reacting cells) was associated with grade III tumors, N0 status, estrogen receptor-negative status, and low cyclin D1 expression. In the whole series of cases, p27 expression did not predict outcome. In node-negative cases (249 patients), high p27 expression indicated poor prognosis. p27 was not prognostically relevant in the group of 223 patients with pT1 disease or in the group of 154 patients <50 years of age. We also investigated the prognostic value of the combined expression of p27 and cyclin D1, but no differences in survival were seen in this bivariate analysis.
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PMID:p27(kip1) expression in breast carcinomas: an immunohistochemical study on 512 patients with long-term follow-up. 1086 99

p27 KIP1 is a cyclin dependent kinase inhibitor, which may act as a potential suppressor gene. Several lines of evidence support the hypothesis that reduced p27 KIP1 expression is related to uncontrolled cell proliferation and tumorigenesis. Low immunohistochemical expression of p27 KIP1 in human neoplasm seems related to tumor progression and poor prognosis. In breast cancer, low p27 is associated with high tumour grade and loss of oestrogen receptor, and it has been suggested that low p27 KIP1 is a powerful and independent prognostic marker of poor clinical outcome. There are however some discrepant results: a few studies, some of which conducted on large series of patients, do not support an independent role of p27 KIP1 as a prognostic marker. We are indeed faced with an intriguing hypothesis, but many more studies are needed to evaluate the real value of p27 KIP1 as a prognostic marker.
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PMID:p27 Expression, a cyclin dependent kinase inhibitor in breast carcinoma. 1093 89

The incidence of cutaneous malignant melanoma is undergoing a dramatic increase in persons with light-color skin in all parts of the world. The prognosis for individuals with advanced disease is dismal due to the lack of effective treatment options. Thus, there is a need for new approaches to control tumor progression. Epidemiological, experimental, and mechanistic data implicate omega-6 polyunsaturated fatty acids (PUFAs) as stimulators and long-chain omega-3 PUFAs as inhibitors of development and progression of a range of human cancers, including melanoma. The aim of this study was to assess the mechanisms by which docosahexaenoic acid (DHA), an omega-3 PUFA, affects human melanoma cells. Exponentially growing melanoma cell lines were exposed in vitro to DHA and then assessed for (a) inhibition of cell growth; (b) expression of cyclins and cyclin-dependent kinase inhibitors in individual cells by flow cytometry and immunocytochemistry using specific monoclonal antibodies to cyclin D1, cyclin E, p21WAF1/CIP1, or p27(KIP1); and (c) expression of total pRb(T) independent of phosphorylation state and hypophosphorylated pRb(P-) in fixed cells by flow cytometry and immunocytochemistry using specific monoclonal antibodies to pRb(T) or pRb(P-), respectively. After treatment with increasing concentrations of DHA, cell growth in a majority of melanoma cell lines (7 of 12) was inhibited, whereas in 5 of 12 cell lines, cell growth was minimally affected. Two melanoma cell lines were examined in detail, one resistant (SK-Mel-29) and one sensitive (SK-Mel-110) to the inhibitory activity of DHA. SK-Mel-29 cells were unaffected by treatment with up to 2 microg/ml DHA whether grown in the absence or presence of 1% fetal bovine serum (FBS). No appreciable change was observed in cell growth, cell cycle distribution, the status of pRb phosphorylation, cyclin D1 expression, or the levels of the cyclin-dependent kinase inhibitors p21 and p27. In contrast, SK-Mel-110 cell growth was inhibited by DHA with the cells accumulating either in G1 or S phase: 0% in SK-Mel-29 versus 13.3 or 41.2% in SK-Mel-110 in the absence or presence of FBS, respectively. In the absence of serum, considerable death occurred by apoptosis. In addition, DHA treatment resulted in increasing numbers of SK-Mel-110 cells (from 12 to >40%) expressing hypophosphorylated pRb, whereas the levels of cyclin D1 and p21 changed little. Expression of p27 in these cells increased >2.5 times when grown in the absence of FBS but not in the presence of 1% FBS. Thus, we show for the first time that DHA inhibits the growth of cultured metastatic melanoma cells. Furthermore, growth inhibition correlates with a quantitative increase in hypophosphorylated pRb in the representative sensitive melanoma cell line SK-Mel-110. Although multiple factors influence pRb phosphorylation, it appears that both cyclin D1 and p21 expression do not change in the presence of DHA, although p27 was strikingly increased in SK-Mel-110 cells in the absence of FBS. The fact that pRb became hypophosphorylated after exposure to DHA suggests a cross-talk mechanism between fatty acid metabolism and the pRb pathway. Determining the mechanism by which PUFAs can inhibit melanoma growth will be an important first step in the rational use of PUFAs as antitumor agents.
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PMID:Cell cycle arrest and apoptosis of melanoma cells by docosahexaenoic acid: association with decreased pRb phosphorylation. 1094 21

Cell cycle progression is facilitated by cyclin-dependent kinases that are activated by cyclins including cyclin D1 and inactivated by cyclin-dependent kinase inhibitors (CDKIs) such as p27. Our previous studies have demonstrated decreased p27 expression in both papillary and more aggressive carcinomas of the thyroid compared to thyroid adenoma and almost similar level of cyclin D1 expression between thyroid adenoma and papillary carcinoma. These results indicate that CDKIs may have an important role in the carcinogenesis of the thyroid and that they probably have a limited role in malignant progression of the thyroid cancer. The role of cyclin D1 in malignant progression of thyroid carcinoma has yet to be established. We studied the expression of cyclin D1 by immunohistochemistry in 34 cases of conventional papillary carcinoma (CPC), 10 cases of minimally invasive follicular carcinoma (MIFC), and 32 cases of more aggressive thyroid carcinoma (ATC), which included 11 tall cell variants, one columnar cell variant of papillary carcinoma, seven insular carcinomas, and 13 anaplastic carcinomas. Cyclin D1 staining was classified by staining score as 0, negative; 1+, less than 25%; 2+, 25 to 50%; and 3+, more than 50% tumor cells staining positive. Kruskal-Wallis one-way ANOVA and Wilcoxon Rank Sum/Mann-Whitney U Test was used to assess the difference in the expression of cyclin D1 between the study groups. Twenty-eight out of the 34 CPCs were cyclin D1 positive, 24 (70%) were 1+, 3 (9%) were 2+, and one (3%) were 3+ positive. Seven of 10 MIFCs were cyclin D1 positive, five (71%) were 1+, and the remaining two (29%) were 2+ positive. On the other hand, 28 of 32 ATCs showed cyclin D1 immunostaining. Of these, three (9%) were 1+, five (13%) were 2+, and 20 (63%) were 3+ positive. This study demonstrates a significant overexpression of cyclin D1 in ATC compared CPC (P < .001) and MIFC (P < .005), suggesting that the cyclin D1 expression may play a role in tumor progression and may have prognostic significance in thyroid cancer.
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PMID:The role of cell cycle regulatory protein, cyclin D1, in the progression of thyroid cancer. 1095 55

Biological markers that are predictive of recurrence and progression of superficial bladder tumors must provide additional information to that provided by multiplicity, size and grade. Field anomalies in normal appearing urothelium of patients with papillary superficial transitional cell carcinoma have been associated with tumor antigens and chromosome 9 deletions. Also, primary tumors with chromosome 9 deletions are associated with a higher risk of recurrence. Abnormal expression of p53, p21 and Ki-67 cell cycle markers have little predictive value for recurrence. However, p53 overexpression or mutation and decreased expression of p27 are associated with cancer progression and survival. New markers, such as mutations in the fibroblast growth factor receptor 3 gene (found in 30% of tumors), anomalies of the PTEN gene and vascular endothelial growth factor expression, may have potential and require further evaluation. Molecular fingerprints of superficial tumors with distinct clinical behavior are being rapidly unravelled. Large-scale clinical studies are urgently needed to provide supportive evidence for their incorporation in clinical management.
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PMID:Can biological markers predict recurrence and progression of superficial bladder cancer? 1100 49

We describe here two patients with mantle cell lymphoma (MCL) who after a few years, developed to the diffuse large cell lymphoma (DLCL)( anaplastic centrocytic lymphoma) growing in a diffuse sheets without the classical MCL component. In both the initial and second biopsy specimens, in each case, tumor cells were positive for cyclin D1, sIgM, sIgD, and CD5, but were negative for CD10 and CD23. In a study of immunoglobulin heavy chain (IgH) gene rearrangement, using the polymerase chain reaction (PCR) method, the products obtained from each paired biopsy tissue sample were the same size, and in one case had an identical sequence to the non-mutated VH gene. Immunohistochemistry was used to examine the expression of p53, p27(Kip1) and cyclin E. Interestingly, there was clear overexpression of p53 protein in case 1 but not in case 2, compared with other typical MCL cases. The expression of p27(Kip1) in the second biopsies of each case was decreased compared with those in the initial biopsies. In case 2, however, p27(Kip1) was clearly expressed in the first and second biopsies, in contrast to other typical MCL cases. Thus these 2 cases demonstrate not only that the variant form of MCL may arise de novo, but also that MCL may transform to DLCL at the time of relapse. Although the mechanism of tumor progression/transformation is still poorly understood, the overexpression of p53 or p27(Kip1) may be linked to a cellular mechanism involved in the development of the variant form of MCL.
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PMID:Expression of Cell Cycle Regulating Proteins in an Unusual Transformation of Mantle Cell Lymphoma. 1104 6


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