Phosphatidylinositol 3-kinase (PI3K) is a key player in cell-growth signaling in a number of lymphoid malignancies, but its role in diffuse large B-cell lymphoma (DLBCL) has not been fully elucidated. Therefore, we investigated the role of the PI3K/AKT pathway in a panel of 5 DLBCL cell lines and 100 clinical samples. Inhibition of PI3K by a specific inhibitor, LY294002, induced apoptosis in SUDHL4, SUDHL5, and SUDHL10 (LY-sensitive) cells, whereas SUDHL8 and OCI-LY19 (LYresistant) cells were refractory to LY294002-induced apoptosis. AKT was phosphorylated in 5 of 5 DLBCL cell lines and inhibition of PI3K caused dephosphorylation/inactivation of constitutively active AKT, FOXO transcription factor, and GSK3 in LY-sensitive cell lines. In addition, there was a decrease in the expression level of inhibitory apoptotic protein, XIAP, in the DLBCL cell lines sensitive to LY294002 after treatment. However, no effect was observed in XIAP protein levels in the resistant DLBCL cell lines following LY294002 treatment. Finally, using immunohistochemistry, p-AKT was detected in 52% of DLBCL tumors tested. Furthermore, in univariate analysis, high p-AKT expression was associated with short survival. In multivariate analysis, this correlation was no longer significant. Altogether, these results suggest that the PI3K/AKT pathway may be a potential target for therapeutic intervention in DLBCL. IntroductionB-cell lymphoma represents the malignant counterpart of normal B cells arrested at specific maturational stages. Diffuse large B-cell lymphoma (DLBCL) is considered to be the most common type of lymphoma in adults, accounting for 30% to 40% of cases of non-Hodgkin lymphoma. 1 Although patients with DLBCLs are potentially curable with combination chemotherapy, the disease proves fatal in approximately 50% of patients. 2 The cause of most DLBCLs remains unknown; however, dysregulation of apoptosis or defective repair plays a role in lymphogenesis. 3 A number of constitutively activated growth signaling pathways have frequently been observed in DLBCL including protein kinase AKT and nuclear factor B (NF-B) transcription factor. [4][5][6] Protein kinases have been implicated as having crucial roles in regulating cell growth, metabolic responses, cell proliferation, migration, and apoptosis, which altogether contribute to tumorigenesis. Constitutive activation of these protein kinases, mainly by phosphorylation, has been implicated as contributing to malignant phenotypes in a number of human cancers. [7][8][9] AKT is a serine threonine kinase that gets activated on growth factor and cytokine stimulation. When phosphoinositide-3,4,5-triphosphate (PIP 3 ) is generated by phosphatidylinositol 3Ј-kinase (PI3K) in response to an intracellular signal, it binds to the PH domain of AKT and translocates to the plasma membrane resulting in the activation of phosphoinositidedependent protein kinases (PDK1 and PDK2). Activated PDK1 and PDK2 phosphorylate at the Thr308 and Ser473 residues of the AKT kinase domain, resulting in its activation. ...

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Metaplastic carcinoma of the breast (MCB) is a rare form of cancer containing mixture of epithelial and mesenchymal elements in variable combinations. Few and conflicting clinical data are available in the literature addressing optimal treatment modalities, prognosis and outcome. A retrospective study was conducted to review all patients with MCB diagnosed and treated at King Faisal Specialist Hospital and Research Center between 1994-2004. The aim is to describe patient's clinicopathologic features and to analyze treatment results. Nineteen female patients were studied. The median age was 48 years (range, 14-58). The median tumor size was 9 cm (range, 3-18). Stage distribution was II in 8 patients, III in 9 and IV in 2. Nine cases were identified as purely epithelial and 10 (53%) as mixed epithelial and mesenchymal metaplasia. Hormone receptors were positive in only 2 patients. Modified radical mastectomy performed in 11 patients and 15 underwent axillary node dissection. Adjuvant chemotherapy was given to 9 patients and postoperative radiotherapy to 8. Twelve patients relapsed with median time of relapse of 12 months (range, 2-28). At a median follow-up of 21 months (range, 7-83), the 3-year event free survival (EFS) and overall survival for the patients diagnosed with loco-regional disease were 15% and 48% respectively. Tumor size correlated significantly with EFS. MCB is an aggressive form of breast cancer associated with poor outcome, high incidence of local recurrence and pulmonary metastases. The disease tends to be estrogen/progesterone receptor negative. Tumor size has an important impact on outcome. The best treatment approach is yet to be defined.

A bstractIntroduction and pur pose. Primary Ewing's sarcoma arising from the bones of the head and neck region is extremely rare representing only 1± 4% of all Ewing's sarcoma cases. Previous reports suggest a better prognosis for that particular anatomic site. The purpose of this study was to analyze the clinico-epidemiologic characteristics of that rare clinical presentation, as well as its patterns of failure and prognosis following treatment. M ater ials and methods. This study included a retrospective review of the medical records of patients with the diagnosis of Ewing's sarcoma of the head and neck region treated at King Faisal Specialist Hospital and Research Center between 1975 and Results . Out of a total number of 24 cases analyzed, there were 17 males and 7 fem ales with a ratio of 2.4:1. The m edian age at diagnosis was 16.5 years. A painful swelling was the m ost comm on clinical presentation. The m axilla was the m ost common site of presentation (9/24 cases). There were 3/24 cases who presented with metastatic disease at diagnosis. The m ajority of patients (16/24 cases) had a tum or size >10 cm . M ost patients were treated with systemic chem otherapy plus localized irradiation following an initial biopsy. W ith a m ean follow up of 3.4 years, the 5-year actuarial overall survival (OS) for the whole group was 53% , while the 5-year actuarial disease-free survival (DFS) was 30% . These ® gures were higher than those reported from our institution for young patients (£ 14 years treated for Ewing' s sarcom a in other anatom ic locations (30 % v 15% ). The response to chem otherapy was the only prognostic factor that affected both the OS and DFS. C onclusio n. The prognosis of Ewing's sarcoma of the head and neck region is slightly better than that of other anatomic sites. The response to systemic chem otherapy is one of the m ost important prognostic factors affecting both DFS and OS of Ewing's sarcoma of the head and neck. M ultimodality therapy consisting of an initial biopsy, aggressive combination chem otherapy and localized radiotherapy is the treatment of choice for Ewing's sarcoma of the head and neck region and m ay result in long-term survival.

This series characterized the clinicopathologic features and outcome of adult patients with early stage WR-NHLs. No survival difference was noted between stage I and stage II, and the outcome was favorable. Primary tonsillar site and the low-risk group of the modified IPI predicted favorable OS and EFS. CMT is probably superior to single modality treatment; however, prospective studies are warranted.