Activation of kinases signalling pathways contributes to various malignant phenotypes in human cancers, including breast tumour. To examine the possible activation of these signalling molecules, we examined the phosphorylation status in 12 protein kinases and transcription factors in normal primary human mammary epithelial cells, telomerase-immortalised human breast epithelial cell line, and two breast cancer lines, MDA-MB-468 and MCF-7, using Kinexus phosphorylated protein screening assays. The phosphorylation of FAK, mTOR, p70S6K, and PDK-1 were elevated in both breast cancer cell lines, whereas the phosphorylation of AKT, EGFR, ErbB2/ Her2, PDGFR, Shc, and Stat3 were elevated in only one breast cancer line compared to normal primary mammary epithelial cells and telomerase-immortalised breast epithelial cells. The same findings were confirmed by Western blotting and by kinase assays. We further substantiated the phosphorylation status of these molecules in tissue microarray slides containing 89 invasive breast cancer tissues as well as six normal mammary tissues with immunohistochemistry staining using phospho-specific antibodies. Consistent findings were obtained as greater than 70% of invasive breast carcinomas expressed moderate to high levels of phosphorylated PDK-1, AKT, p70S6K, and EGFR. In sharp contrast, phosphorylation of the same proteins was nearly undetectable or was at low levels in normal mammary tissues under the same assay. Elevated phosphorylation of PDK-1, AKT, mTOR, p70S6K, S6, EGFR, and Stat3 were highly associated with invasive breast tumours (Po0.05). Taken together, our results suggest that activation of these kinase pathways by phosphorylation may in part account for molecular pathogenesis of human breast carcinoma. Particularly, moderate to high level of PDK-1 phosphorylation was found in 86% of high-grade metastasised breast tumours. This is the first report demonstrating phosphorylation of PDK-1 is frequently elevated in breast cancer with concomitantly increased phosphorylation of downstream kinases, including AKT, mTOR, p70S6K, S6, and Stat3. This finding thus suggested PDK-1 may promote oncogenesis in part through the activation of AKT and p70S6K and rationalised that PDK-1 as well as downstream components of PDK-1 signalling pathway may be promising therapeutic targets to treat breast cancer. Breast cancer remains to be a major cause of death in women worldwide, despite improvements in cancer prevention, early detection, treatment, and understanding the molecular pathogenesis. It hence demands an urgent need to unveil the exact mechanism of oncogenesis and tumour progression, which may prelude the development of new strategies for treatment. Breast carcinoma emerges through multistep processes progressing from hyperplasia to premalignant change, in situ carcinoma, invasion, and distal metastasis, in concomitant with gain of oncogenic activities and loss of tumour suppressor gene functions.Protein kinases have been implicated in playing crucial roles in regulating cell growth, met...

Rhabdomyosarcoma (RMS) is the most common paediatric soft-tissue sarcoma including two major subtypes, alveolar rhabdomyosarcoma (ARMS) and embryonal rhabdomyosarcoma (ERMS). Increasing evidence suggests that oncogenesis of RMS involves multistages of signalling protein dysregulation which may include prolonged activation of serine/threonine kinases such as phosphoinositide-dependant kinase-1 (PDK-1) and AKT. To date, whether PDK-1/AKT pathway is activated in RMS is unknown. This study was to examine phosphorylation status of AKT and to evaluate a novel small molecular inhibitor, OSU-03012 targeting PDK-1 in RMS. We examined phosphorylation levels of AKT using ARMS and ERMS tissue microarray and immunohistochemistry staining. Our results showed phospho-AKT Thr308 level is elevated 42 and 35% in ARMS and ERMS, respectively. Phospho-AKT Ser473 level is also increased 43% in ARMS and 55% in ERMS. Furthermore, we showed that OSU-03012 inhibits cell viability and induces apoptosis in ARMS and ERMS cell lines (RH30, SMS-CTR), which express elevated phospho-AKT levels. Normal cells are much less sensitive to OSU-03012 and in which no detectable apoptosis was observed. This study showed, for the first time, that PDK-1/AKT pathway is activated in RMS and may play an important role in survival of RMS. PDK-1/AKT pathway may be an attractive therapeutic target for cancer intervention in RMS using OSU-03012.

A reduced content of functional collagenase observed in OSF mucosa of patients might be one mechanism responsible for collagen accumulation. Intervention of OSF by collagenase treatment at the early stage may reduce the incidence of developing oral carcinoma.

Cyclosporine A (CsA) may predispose to gingival overgrowth under inflammatory environments. The regulation of PAI-1 expression induced by CsA might be critically related with the intracellular glutathione and the ERK-MAPK pathway.

Hypophosphatemia developed in a normophosphatemic patient after 9 h of hemodialysis therapy (using a phosphate-free dialysate) administered for the treatment of ethylene glycol poisoning. The hypophosphatemia was promptly improved with additional hemodialysis treatment using a phosphorus-enriched dialysate.

We analyzed the replicon types, sizes, and restriction fragment length polymorphism (RFLP) typing of plasmids carrying extended-spectrum β-lactamase (ESBL) genes in Klebsiella pneumoniae isolates from Taiwan. Fifty-one Escherichia coli transconjugant strains with plasmids from ESBL-producing K. pneumoniae from the Taiwan Surveillance of Antimicrobial Resistance III Program in 2002 were included. All the 51 plasmids carried a bla gene, the majority of which were bla (28/51 [54.9%]). Plasmids ranged in size from 126 to 241 kb by S1 nuclease digestion and subsequent pulsed-field gel electrophoresis, and the most common plasmid size (37.3%) was 161-170 kb. The most common replicon type of plasmids was incompatibility group (Inc)A/C (60.8%). The IncA/C plasmids all carried bla (bla), and some also carried bla (bla) genes. All 51 plasmids could be typed with PstI, and 27 (52.9%) belonged to 10 clusters. Thirty-eight of the 51 plasmids were typable with BamHI, and 21 plasmids (55.3%) fell into 7 clusters. Plasmids in the same cluster belonged to the same incompatibility group, with the exception of cluster C6. In conclusion, IncA/C plasmids are the main plasmid type responsible for the dissemination of ESBL genes of K. pneumoniae from Taiwan. RFLP with PstI possessed better discriminatory power than that with BamHI and PCR-based replicon typing for ESBL-carrying plasmids in K. pneumoniae in this study. Greater than 50% of plasmids fell into clusters, and >60% of cluster-classified plasmids were present in clonally unrelated isolates, indicating that horizontal transfer of plasmids plays an important role in the spread of ESBL genes.

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