PubMed · 16368384
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
Frederic Grannis. 2006. Invited commentary.. https://doi.org/10.1016/j.athoracsur.2005.08.038
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The EGF/IGF growth factors are potent mitogens that regulate cell proliferation and cell survival and are involved in prostate cancer development. Using laser microdissection technology and real-time PCR, together with immunohistochemistry, we have explored the growth factor and integrin dependent PI3-kinase/PTEN/Akt signalling pathway in prostate cell lines and tumour samples by analysing EGF-R, IGF1-R, ILK, beta3 integrin, PTEN and p-Akt protein expression. We provide evidence that loss of PTEN expression rather than upregulated EGF/IGF1 receptor expression was responsible for increased p-Akt in neoplastic prostate cells. We therefore compared PTEN expression in patient biopsies at first time diagnosis recruited prospectively (Study I, 112 patients) and patients with confirmed metastasis recruited retrospectively from the Luxembourg cancer registry (Study II, 42 patients). In Study I, loss of PTEN expression at first time diagnosis was found in 26 of 112 patients (23%). In Study II, 25 of the 42 patients (59%) with lymph node metastasis had complete loss of PTEN expression in both the neoplastic glands of the prostate and the invasive prostate cancer cells in the lymph node, and of these 13 (52%) exhibited already loss of PTEN expression at first diagnosis. These findings demonstrate that loss of PTEN expression is an important factor in progression towards metastatic disease and could potentially serve as an early prognostic marker for prostate cancer metastasis.
BACKGROUND AND OBJECTIVES: Tissue factor (TF), which normally safeguards vascular integrity by inducing hemostasis upon injury, has received widespread attention in the pathogenesis of cancer progression and metastasis. Aberrantly expressed TF in cancer cells has been reported to be associated with advanced stages of malignancy in various cancers. METHODS: The expression of TF and microvessel density (MVD) were immunohistochemically evaluated in 207 gastric cancers, and their relationship with clinicopathological features was examined. RESULTS: TF was preferentially expressed (41.8%) in intestinal-type cancer at a significantly higher rate than that in diffuse-type cancer (12.1%, P<0.0001). The expression of TF was associated with advanced stage of disease and showed a positive correlation with a higher rate of lymphatic and venous invasion and lymphatic metastasis in intestinal-type, but not in diffuse-type carcinoma. Moreover, TF expression was associated with high MVD in the tumor and a worse outcome only in intestinal-type carcinoma. CONCLUSIONS: TF may be critically involved in tumor progression in intestinal-type, but not in diffuse-type, gastric carcinoma. The difference in clinical features between these two histological types might be partially dependent on TF expression profile.
microRNAs are functional, 22 nt, noncoding RNAs that negatively regulate gene expression. Disturbance of microRNA expression may play a role in the initiation and progression of certain diseases. A microRNA expression signature has been identified that is associated with pancreatic cancer. This has been accomplished with the application of real-time PCR profiling of over 200 microRNA precursors on specimens of human pancreatic adenocarcinoma, paired benign tissue, normal pancreas, chronic pancreatitis and nine pancreatic cancer cell lines. Hierarchical clustering was able to distinguish tumor from normal pancreas, pancreatitis and cell lines. The PAM algorithm correctly classified 28 of 28 tumors, 6 of 6 normal pancreas and 11 of 15 adjacent benign tissues. One hundred microRNA precursors were aberrantly expressed in pancreatic cancer or desmoplasia (p < 0.01), including microRNAs previously reported as differentially expressed in other human cancers (miR-155, miR-21, miR-221 and miR-222) as well as those not previously reported in cancer (miR-376a and miR-301). Most of the top aberrantly expressed miRNAs displayed increased expression in the tumor. Expression of the active, mature microRNA was validated using a real-time PCR assay to quantify the mature microRNA and Northern blotting. Reverse transcription in situ PCR showed that three of the top differentially expressed miRNAs (miR-221, -376a and -301) were localized to tumor cells and not to stroma or normal acini or ducts. Aberrant microRNA expression may offer new clues to pancreatic tumorigenesis and may provide diagnostic biomarkers for pancreatic adenocarcinoma.