Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01034 (cystatin C)
 3,397 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

DNA isolated from cell line Mel Swift, a human melanoma cell line, transforms NIH3T3 cells. Southern blot analysis of DNA from secondary foci revealed conserved 8.8- and 7.8-kilobase EcoRI fragments which hybridized with a human repetitive sequence clone, blur 8. The activated transforming gene was identified as N-ras, and the 8.8-kilobase EcoRI fragment from a secondary transformant was cloned. Synthetic 17-mer oligonucleotides which spanned either the normal codon 61 (CAA) or a mutant codon 61 (AAA) were used for hybridization. Cloned N-ras from melanoma cell line Mel Swift hybridized to the mutant (AAA) oligonucleotide. From this we predicted a glutamine-to-lysine substitution in amino acid 61, a change confirmed by conventional sequencing of the first and second exons of N-ras from cell line Mel Swift. Transfection experiments showed that only those recombinant clones with the mutation in position 61 were biologically active.
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PMID:Activation of N-ras in a human melanoma cell line. 388 33

Although increased expression of cysteine proteinases has been shown to be correlated with increased metastasis for a wide variety of tumours, the contribution of cysteine proteinases to the metastatic spread of tumour cells is not well understood. In order to examine this question we have overexpressed a specific cysteine proteinase inhibitor, cystatin C, by stable transfection of B16F10 melanoma. Increased expression of cystatin C inhibited motility and in vitro invasiveness of B16 melanoma by 50% in both stimulated (autocrine motility factor, laminin) and unstimulated cells. These results suggest that cysteine proteinases are involved in B16 melanoma motility and invasion.
Melanoma Res 1997 Apr
PMID:Inhibition of motility and invasion of B16 melanoma by the overexpression of cystatin C. 916 74

The levels of cathepsins (Cats) B, H, and L and their inhibitors stefin A and cystatin C were determined in the sera of 43 patients with metastatic melanoma, in 54 patients with treated cutaneous melanoma with no evidence of metastatic disease, and in 30 healthy blood donors, using quantitative ELISAs. The levels of Cats B and H and cystatin C were significantly higher within the group of metastatic melanoma patients compared with the healthy controls. The median Cat B was 4.8 versus 3.6 ng/ml (P < 0.013), the median Cat H was 13.7 versus 4.9 ng/ml (P < 0.0001), and the median cystatin C was 470 versus 320 ng/ml (P < 0.02). Cat H was also significantly increased within the group of melanoma patients with no metastasis, with a median of 9.6 ng/ml. Cat B was found to correlate with Cat L (r = 0.36; P < 0.02) and cystatin C (r = 0.41; P < 0.008). The serum level of Cat H was significantly increased in patients showing no response to the chemoimmunotherapy as compared to the level in responders. Metastatic melanoma patients with high contents of Cat B and Cat H experienced significantly shorter overall survival rates than the patients with low levels of each enzyme (Cat B: P < 0.003 and relative risk, 2.5; Cat H: P < 0.006 and relative risk, 2.4, using medians as cutoff values). The other potential factors for prognosis for this group of patients revealed moderate (histological type and age) or no (tumor thickness, sex, and lymph node metastasis) prognostic significance. Similarly, no difference in survival was found for stefin A, cystatin C, and Cat L. These results suggest that the serum levels of Cats B and H could serve as prognostic factors for patients with advanced melanoma.
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PMID:Cathepsins B, H, and L and their inhibitors stefin A and cystatin C in sera of melanoma patients. 981 68

Eighteen human congenital melanocytic naevi (CMN) from 17 patients were screened for activating point mutations in the oncogenes N-ras and CDK4 and for sequence variants in the MC1R gene by combined RFLP-PCR/SSCP analysis. In addition, all lesions were screened for deletions and point mutations in the tumour suppressor genes p53 and p16INK4a (CDKN2A) by combined multiplex PCR/SSCP analysis. Positive screening data were specified by sequencing of the corresponding PCR product. Activating point mutations in the N-ras gene (nine CAA (Gln) to AAA (Lys) transversions and one CAA (Gln) to CGA (Arg) transition at codon 61) were detected at high frequency (56%). Furthermore, three missense mutations (V92M) and two silent mutations (CGA (Arg) to CGG (Arg), codon 213, exon 6) were found in the MC1R and p53 genes, respectively. No mutations were found in p16 or CDK4. The activated N-ras oncogene, which is also found in human cutaneous melanomas, may constitute a potential risk factor for melanoma formation within CMN.
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PMID:Mutational analysis of the N-ras, p53, p16INK4a, CDK4, and MC1R genes in human congenital melanocytic naevi. 1046 11

Progression to metastasis has been correlated with increased cysteine proteinase activity for a number of tumour types. One mechanism of cysteine proteinase regulation in normal cells is by natural protease inhibitors, the cystatins. Here we further characterize a transfected cell line showing increased cystatin C transcription driven by cytomegalovirus (CMV) promoter/enhancer sequences. Properties of this cystatin C altered cell line such as growth in vitro, lung colonization after tail vein injection in mice, production of cystatin, and cysteine proteinase inhibitor activities were examined. Although there was no difference between the growth rate of the cystatin transfected cell line and that of the control, there was a substantial difference in metastatic ability. No increase was noted in cystatin C secretion into the media for the cystatin C transfected cell line compared with the control transfected cell line. There was, however, a difference in cysteine protease inhibitor activity in the cell-free extracts. These results show that alteration of cystatin C levels by overexpression in B16 melanoma alters properties associated with metastasis.
Melanoma Res 1999 Aug
PMID:Inhibition of B16 melanoma metastasis by overexpression of the cysteine proteinase inhibitor cystatin C. 1050 55

Cathepsins B, H and L have been shown to participate in processes of tumor growth, vascularization, invasion and metastasis. Their levels in tumor tissue extracts can provide useful clinical information to predict disease-free and overall survival in breast, lung, colorectal, brain and head and neck cancer patients. Recently we have found that both cysteine cathepsins and their endogenous protein inhibitors stefins and cystatin C can also predict prognosis when measured extracellularly. In melanoma and colorectal cancer patients high serum levels of cathepsins B and H correlated with shorter survival. Similarly, increased extracellular levels of stefins A and B and cystatin C correlated significantly with high risk of adverse outcome in cancer patients. However, the cathepsin B/cystatin C complex was found to be less abundant in sera of patients with malignant tumors than in those with benign diseases or in healthy controls, suggesting an imbalance between the enzyme and its inhibitor in cancer patients.
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PMID:Cysteine proteinases and their inhibitors in extracellular fluids: markers for diagnosis and prognosis in cancer. 1076 47

We have analyzed the expression of the CDKN1A (p21(CIP1)), CDKN1B (p27(Kip1)), TP53, RB1 and MDM2 proteins and tumor cell proliferation by immunohistochemical staining in 59 cases of metastatic melanoma. The genomic status of the CDKN2A (INK4-ARF, p16/p14(ARF)), CDKN2B (p15) and CDKN2C (p18) genes was determined by PCR-SSCP (single-strand conformation polymorphism) in 46 of these cases. These results were correlated with various clinico-pathological parameters, including the outcome of combined chemoimmunotherapy. We found positive correlations between the expression of CDKN1A and MDM2 (r = 0.5063, P = 0.001), between the expression of CDKN1B and RB1 (r = 0.5026, P = 0.001), and between RB1 expression and tumor cell proliferation (0.5564, P<0.001). Two mutations in the CDKN2A (p16) gene were detected, including a novel base change AAC-->ATC (Asn to Ile) at codon 71, that also changes the codon 85 of the alternative reading frame gene p14(ARF) from CAA to CAT (Gln to His). Homozygous deletion at exon 2 of the CDKN2A (INK4-ARF) gene was detected in six cases. In seven cases, the 540C-->G polymorphism in the 3'UTR of the CDKN2A (p16) gene was found in linkage disequilibrium with the 74C-->A polymorphism in intron 1 of the CDKN2B gene (P < 0.0001). These cases had significantly lower expression of the TP53 protein (P = 0.0032). Both 540C-->G and 580C-->T polymorphisms in the 3'UTR of the CDKN2A (p16) gene were associated with significantly shorter progression time from primary to metastatic disease (P = 0.0071). We conclude, that although none of the analyzed cell cycle regulators could be singled out as a major prognostic factor, G(1)/S checkpoint abnormalities remain one of the most significant factors in the development of malignant melanoma.
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PMID:Analysis of G(1)/S checkpoint regulators in metastatic melanoma. 1086 49

The majority of human melanomas harbor activating mutations in either the BRAF or NRAS gene. To date, the role of oncogenic NRAS in melanoma remains poorly defined and no current therapies are directed at specifically suppressing oncogenic NRAS in human melanoma tumors. The aim of our study, therefore, was to investigate the effects of suppressing oncogenic NRAS in human melanoma cell lines in vitro. Using both small interfering RNA- and plasmid based-RNA interference techniques, oncogenic NRAS was specifically suppressed in 2 human melanoma cell lines, 224 and BL, which harbor a codon 61 CAA (glutamine) to CGA (arginine) NRAS mutation. Suppression of oncogenic NRAS in these cell lines resulted in increased apoptosis. Furthermore, in 224 cells we demonstrated decreased phosphorylation of extracellular signal-regulated kinase (ERK) and Akt, and reduced expression of NF-kappaB and cyclin D1 in the N-Ras signaling pathway. In contrast, RNA interference directed at wild-type (WT) NRAS had no significant effect on apoptosis of 224 cells or 2 human melanoma cell lines (A375 and 397) containing WT NRAS but a codon 600 GTG (valine) to GAG (glutamate) mutation in BRAF. These data suggest that oncogenic NRAS is important for avoidance of apoptosis in melanomas that harbor the codon 61 NRAS mutation and emphasizes oncogenic NRAS as a therapeutic target in patients with tumors that harbor this mutation.
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PMID:Suppression of oncogenic NRAS by RNA interference induces apoptosis of human melanoma cells. 1568 5

BACKGROUND: Tumor metastasis is a frequent cause of treatment failure for cancer patients. A key feature of metastatic cancer cells is their invasive ability. Cysteine proteases contribute to invasive properties of many cancer cell types. To analyze the contribution of cysteine proteases to metastasis we have over-expressed in B16 melanoma cells the natural cysteine protease inhibitor, cystatin C. We measured in vitro invasion of cystatin over-expression clones with Boyden chamber type assays. Tail-vein injections of cells were used to compare lung tumor colonization. Subcutaneous tumor growth and tumor cell metastasis from primary tumors were also analyzed. Apoptosis of tumor cells was measured in lung tissues following melanoma cell injection. RESULTS: Results show the in vitro invasion of cystatin C over-expressing cells was dramatically inhibited. Lung tumor colonization was also reduced. Increased tumor cell apoptosis was found to be an important factor and may be related to the reduced tumor burden noted in this system of melanoma metastasis. CONCLUSION: Cysteine proteases therefore, may be a target for future anti-metastatic therapies.
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PMID:Late stage inhibition of hematogenous melanoma metastasis by cystatin C over-expression. 1590 19

The ratio between proteases and their inhibitors is unbalanced in cancer. The cysteine protease inhibitor cystatin C is internalized by some cancer cells, which affects cellular properties. Here we aimed to investigate if uptake of cystatin C and the related inhibitor cystatin E/M occur in melanoma cell lines and to evaluate to what extent the uptake affects the legumain activity that is typically increased in melanoma. First we studied the basic expression, secretion, and intracellular content of all type 2 cystatins as well as expression and activity of their possible target enzymes legumain and cathepsin B in MDA-MB-435S, A375, and C8161 melanoma cells. Legumain activity was measureable in all cell lines, and of the potential legumain inhibitors, cystatin C, E/M, and F, cystatin C was the one mainly produced. All cells internalized cystatin C added to culture media, leading to increased intracellular cystatin C levels by 120-200%. Cystatin E/M was internalized as well but at a modest rate. The effects on intracellular legumain activity were nevertheless pronounced, probably because the cells lacked this inhibitor, and its affinity for legumain is 100-fold higher than that of cystatin C. Likewise, the low-degree uptake resulted in reduced migration and invasion of A375 cells in Matrigel to an extent comparable with the W106F variant of cystatin C with optimal uptake properties and resulting in much higher intracellular levels. Thus, cystatin E/M appears to be a good candidate to efficiently down-regulate the increased legumain activity, possibly important for the malignant phenotype of melanoma cells.
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PMID:Low-level internalization of cystatin E/M affects legumain activity and migration of melanoma cells. 2863 39


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