Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The GIMAP (GTPase of the immunity-associated protein) gene family includes seven functional members residing on human chromosome 7. GIMAP genes encode GTP-binding proteins that share a unique primary structure and whose function is largely unknown. However, gene ablation studies reveal that Gimap4 plays an important role in regulating the apoptosis of T cells. In a pilot microarray analysis on six cases of non-small cell lung cancer (NSCLC), we discovered that the expression of GIMAP family members, but not the neighboring non-GIMAP genes, was uniformly lower in the tumor tissues, compared to that in the adjacent nontumor tissues. This finding was subsequently confirmed by quantitative PCR assays in a total of twenty NSCLCs, and we found that GIMAP6 and GIMAP8 showed striking reduction of gene expression in the tumors. In contrast, GIMAP8 mRNA level was abnormally elevated in the adjacent nontumor tissues as compared to that in the control lung tissues. Such reciprocal expression of GIMAPs suggests that this unique gene family might contribute to the pathogenesis of and immune reactions to NSCLC.
Lung Cancer 2008 Dec
PMID:Dysregulation of GIMAP genes in non-small cell lung cancer. 1846 27

Currently, serum biomarkers might usually be thought not to be used for early detection of lung cancer by some researchers. In this study, we used a highly optimized ClinProt-matrix-assisted laser desorption/ionization time-of flight mass spectrometer (MALDI-TOF-MS) to screen non-small cell lung carcinoma (NSCLC) markers in serum. A training set of spectra derived from 45 NSCLC patients, 24 patients with benign lung diseases (BLDs) and 21 healthy individuals, was used to develop a proteomic pattern that discriminated cancer from non-cancer effectively. A test set, including 74 cases (29 NSCLC patients and 45 controls), was used to validate this pattern. After cross-validation, the classifier showed sensitivity and specificity, 86.20% and 80.00%, respectively. Remarkably, 100% of early stage serum samples could be correctly classified as lung cancer. Furthermore, the differential peptides of 1865Da and 4209Da were identified as element of component 3 and eukaryotic peptide chain release factor GTP-binding subunit ERF, respectively. The patterns we described and peptides we identified may have clinical utility as surrogate markers for detection and classification of NSCLC.
 ...
PMID:Biomarker discovery and identification from non-small cell lung cancer sera. 2119 79

Folate, an important nutrient in the human diet, has been implicated in cancer, but its role in metastasis is not established. We have shown previously that the withdrawal of medium folate leads to the inhibition of migration and invasion of A549 lung carcinoma cells. Here we have demonstrated that medium folate regulates the function of Rho GTPases by enabling their carboxyl methylation and translocation to plasma membrane. Conversely, the lack of folate leads to the retention of these proteins in endoplasmic reticulum. Folate also promoted the switch from inactive (GDP-bound) to active (GTP-bound) GTPases, resulting in the activation of downstream kinases p21-activated kinase and LIM kinase and phosphorylation of the actin-depolymerizing factor cofilin. We have further demonstrated that in A549 cells two GTPases, RhoA and Rac1, but not Cdc42, are immediate sensors of folate status: the siRNA silencing of RhoA or Rac1 blocked effects of folate on cofilin phosphorylation and cellular migration and invasion. The finding that folate modulates metastatic potential of cancer cells was confirmed in an animal model of lung cancer using tail vein injection of A549 cells in SCID mice. A folate-rich diet enhanced lung colonization and distant metastasis to lymph nodes and decreased overall survival (35 versus 63 days for mice on a folate-restricted diet). High folate also promoted epithelial-mesenchymal transition in cancer cells and experimental mouse tumors. Our study provides experimental evidence for a mechanism of metastasis promotion by dietary folate and highlights the interaction between nutrients and metastasis-related signaling.
...
PMID:Rho GTPases RhoA and Rac1 mediate effects of dietary folate on metastatic potential of A549 cancer cells through the control of cofilin phosphorylation. 2508 46

KRAS is one of the most frequently mutated oncogenes in human non-small cell lung cancers (NSCLCs). RAS proteins trigger multiple effector signalling pathways including the highly conserved RAF-MAPK pathway. CRAF, a direct RAS effector protein, is required for KRAS-mediated tumourigenesis. Thus, the molecular mechanisms driving the activation of CRAF are intensively studied. Prohibitin 1 (PHB1) is an evolutionarily conserved adaptor protein and interaction of CRAF with PHB1 at the plasma membrane is essential for CRAF activation. Here, we demonstrate that PHB1 is highly expressed in NSCLC patients and correlates with poor survival. Targeting of PHB1 with two chemical ligands (rocaglamide and fluorizoline) inhibits epidermal growth factor (EGF)/RAS-induced CRAF activation. Consistently, treatment with rocaglamide inhibited proliferation, migration and anchorage-independent growth of KRAS-mutated lung carcinoma cell lines. Surprisingly, rocaglamide treatment inhibited Ras-GTP loading in KRAS-mutated cells as well as in EGF-stimulated cells. Rocaglamide treatment further prevented the oncogenic growth of KRAS-driven lung cancer allografts and xenografts in mouse models. Our results suggest rocaglamide as a RAS inhibitor and that targeting plasma membrane-associated PHB1 with chemical ligands would be a viable therapeutic strategy to combat KRAS-mediated NSCLCs.
 ...
PMID:Targeting prohibitins with chemical ligands inhibits KRAS-mediated lung tumours. 2884 16

The tumor suppressor p53 protein is either lost or mutated in about half of all human cancers. Loss of p53 function is well known to influence cell spreading, migration and invasion. While expression of mutant p53 is not equivalent to p53 loss, mutant p53 can acquire new functions to drive cell spreading and migration via different mechanisms. In our study, we found that mutant p53 significantly increased cell spreading and migration when comparing with p53-null cells. RNA-Seq analysis suggested that Rho GTPase activating protein 44 (ARHGAP44) is a new target of mutant p53, which suppressed ARHGAP44 transcription. ARHGAP44 has GAP activity and catalyze GTP hydrolysis on Cdc42. Higher level of GTP-Cdc42 was correlated with increase expression of mutant p53 and reduced ARHGAP44. Importantly, wt-ARHGAP44 but not mutant ARHGAP44 (R291A) suppressed mutant p53 mediated cell spreading and migration. Bioinformatics analysis indicated lower expression of ARHGAP44 in lung carcinoma compared with normal tissues, which was verified by RT-qPCR using specimens from patients. More interestingly, ARHGAP44 mRNA level was lower in tumors with mutant p53 than those with normal p53. Collectively, our results disclose a new mechanism by which mutant p53 stimulates cell spreading and migration.
 ...
PMID:Mutant p53 promotes cell spreading and migration via ARHGAP44. 2852 13

The RAS oncogenes are frequently mutated in human cancers and among the three isoforms (KRAS, HRAS and NRAS), KRAS is the most frequently mutated oncogene. Here, we demonstrate that a subset of flavaglines, a class of natural anti-tumour drugs and chemical ligands of prohibitins, inhibit RAS GTP loading and oncogene activation in cells at nanomolar concentrations. Treatment with rocaglamide, the first discovered flavagline, inhibited the nanoclustering of KRAS, but not HRAS and NRAS, at specific phospholipid-enriched plasma membrane domains. We further demonstrate that plasma membrane-associated prohibitins directly interact with KRAS, phosphatidylserine and phosphatidic acid, and these interactions are disrupted by rocaglamide but not by the structurally related flavagline FL1. Depletion of prohibitin-1 phenocopied the rocaglamide-mediated effects on KRAS activation and stability. We also demonstrate that flavaglines inhibit the oncogenic growth of KRAS-mutated cells and that treatment with rocaglamide reduces non-small-cell lung carcinoma (NSCLC) tumour nodules in autochthonous KRAS-driven mouse models without severe side effects. Our data suggest that it will be promising to further develop flavagline derivatives as specific KRAS inhibitors for clinical applications.
 ...
PMID:A subset of flavaglines inhibits KRAS nanoclustering and activation. 3250 Dec 81


<< Previous 1 2