University of South Florida

About: University of South Florida is a education organization based out in Tampa, Florida, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 34231 authors who have published 72644 publications receiving 2538044 citations. The organization is also known as: USF.

Persistent Activation of Stat3 Signaling Induces Survivin Gene Expression and Confers Resistance to Apoptosis in Human Breast Cancer Cells

Abstract: Purpose: Signal transducer and activator of transcription 3 (Stat3) protein is persistently activated in breast cancer and promotes tumor cell survival. To gain a better understanding of the role of constitutive Stat3 signaling in breast cancer progression, we evaluated the expression profile of potential Stat3-regulated genes that may confer resistance to apoptosis. Experimental Design: Stat3 signaling was blocked with antisense oligonucleotides in human MDA-MB-435s breast cancer cells and Affymetrix GeneChip microarray analysis was done. The candidate Stat3 target gene Survivin was further evaluated in molecular assays using cultured breast cancer cells and immunohistochemistry of breast tumor specimens. Results: Survivin, a member of the inhibitor of apoptosis protein family, was identified as a potential Stat3-regulated gene by microarray analysis. This was confirmed in Survivin gene promoter studies and chromatin immunoprecipitation assays showing that Stat3 directly binds to and regulates the Survivin promoter. Furthermore, direct inhibition of Stat3 signaling blocked the expression of Survivin protein and induced apoptosis in breast cancer cells. Direct inhibition of Survivin expression also induced apoptosis. Increased Survivin protein expression correlates significantly ( P = 0.001) with elevated Stat3 activity in primary breast tumor specimens from high-risk patients who were resistant to chemotherapy treatment. Conclusions: We identify Survivin as a direct downstream target gene of Stat3 in human breast cancer cells that is critical for their survival in culture. Our findings suggest that activated Stat3 signaling contributes to breast cancer progression and resistance to chemotherapy by, at least in part, inducing expression of the antiapoptotic protein, Survivin.

Surgical Complications Associated With Sentinel Lymph Node Biopsy: Results From a Prospective International Cooperative Group Trial

Abstract: Background: American College of Surgeons Oncology Group Z0010 is a prospective multicenter trial designed to evaluate the prognostic significance of micrometastases in the sentinel lymph nodes and bone marrow aspirates of women with early-stage breast cancer. Surgical complications associated with the sentinel lymph node biopsy surgical procedure are reported. Methods: Eligible patients included women with clinical T1/2N0M0 breast cancer. Surgical outcomes were available at 30 days and 6 months after surgery for 5327 patients. Patients who had a failed sentinel node mapping (n = 71, 1.4%) or a completion lymph node dissection (n = 814, 15%) were excluded. Univariate and multivariate analyses were performed to identify predictors for the measured surgical complications. Results: In patients who received isosulfan blue dye alone (n = 783) or a combination of blue dye and radiocolloid (n = 4192), anaphylaxis was reported in .1% of subjects (5 of 4975). Other complications included axillary wound infection in 1.0%, axillary seroma in 7.1%, and axillary hematoma in 1.4% of subjects. Only increasing age and an increasing number of sentinel lymph nodes removed were significantly associated with an increasing incidence of axillary seroma. At 6 months, 8.6% of patients reported axillary paresthesias, 3.8% had a decreased upper extremity range of motion, and 6.9% demonstrated proximal upper extremity lymphedema (change from baseline arm circumference of >2 cm). Significant predictors for surgical complications at 6 months were a decreasing age for axillary paresthesias and increasing body mass index and increasing age for upper extremity lymphedema. Conclusions: This study provides a prospective assessment of the sentinel lymph node biopsy procedure, as performed by a wide range of surgeons, demonstrating a low complication rate.

The neuropsychological impact of sports-related concussion: a meta-analysis.

Abstract: There is increasing interest in the potential neuropsychological impact of sports-related concussion. A meta-analysis of the relevant literature was conducted to determine the impact of sports-related concussion across six cognitive domains. The analysis was based on 21 studies involving 790 cases of concussion and 2014 control cases. The overall effect of concussion (d = 0.49) was comparable to the effect found in the non-sports-related mild traumatic brain injury population (d = 0.54; Belanger et al., 2005). Using sports-concussed participants with a history of prior head injury appears to inflate the effect sizes associated with the current sports-related concussion. Acute effects (within 24 hr of injury) of concussion were greatest for delayed memory, memory acquisition, and global cognitive functioning (d = 1.00, 1.03, and 1.42, respectively). However, no residual neuropsychological impairments were found when testing was completed beyond 7 days postinjury. These findings were moderated by cognitive domain and comparison group (control group versus preconcussion self-control). Specifically, delayed memory in studies utilizing a control group remained problematic at 7 days. The implications and limitations of these findings are discussed.