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1.  Prolonged Treatment Time Deteriorates Positioning Accuracy for Stereotactic Radiosurgery 
PLoS ONE  2015;10(4):e0123359.
The accuracy of radiation delivery is increasingly important as radiotherapy technology continues to develop. The goal of this study was to evaluate intrafractional motion during intracranial radiosurgery and the relationship between motion change and treatment time.
Methods and Materials
A total of 50 treatment records with 5988 images, all acquired during treatments with the CyberKnife Radiosurgery System, were retrospectively analyzed in this study. We measured translation and rotation motion including superior-inferior (SI), right-left (RL), anterior-posterior (AP), roll, tilt and yaw. All of the data was obtained during the first 45 minutes of treatment. The records were divided into 3 groups based on 15-min time intervals following the beginning of treatment: group A (0-15 min), group B (16-30 min) and group C (31-45 min). The mean deviations, systematic errors, random errors and margin for planning target volume (PTV) were calculated for each group.
The mean deviations were less than 0.1 mm in all three translation directions in the first 15 minutes. Greater motion occurred with longer treatment times, especially in the SI direction. For the 3D vector, a time-dependent change was observed, from 0.34 mm to 0.77 mm (p=0.01). There was no significant correlation between the treatment time and deviations in the AP, LR and rotation axes. Longer treatment times were associated with increases in systematic error, but not in random error. The estimated PTV margin for groups A, B and C were 0.86 / 1.14 / 1.31 mm, 0.75 / 1.12 / 1.20 mm, and 0.43 / 0.54 / 0.81 mm in the SI, RL, and AP directions, respectively.
During intracranial radiosurgery, a consistent increase in the positioning deviation over time was observed, especially in the SI direction. If treatment time is greater than 15 minutes, we recommend increasing the PTV margins to ensure treatment precision.
PMCID: PMC4404334  PMID: 25894841
2.  Clinicopathologic features and responses to radiotherapy of myeloid sarcoma 
To evaluate clinicopathological features, radiotherapeutic parameters, and their associations with responses to radiotherapy (RT) in patients with myeloid sarcoma (MS).
We reviewed 20 patients receiving RT for MS lesions (in 43 RT courses) and analyzed the patients’ clinicopathologic features and radiotherapeutic parameters, and their associations with complete responses (CR) to RT using Fisher’s exact test and univariate logistic regression analysis. Generalized Estimating Equation was used to analyze all 43 irradiated lesions and account for the correlations in RT responses among lesions from the same patient.
We found that the underlying hematological diseases of the evaluated patients were acute myeloid leukemia (AML) in 14 patients (70%), chronic myeloid leukemia in 4 patients (20%), myelodysplastic syndrome with AML transformation in one patient (5%), and de novo MS in one patient (5%). Most patients (55%) received RT for MS at the time of relapse following bone marrow transplantation (BMT). The most common cytogenetic abnormality was t(8;21)(q22;q22). The median RT dose of 20 Gy (range 6–35 Gy), administered in 1.5-3.5 Gy fractions, provided a 63% CR rate. RT dose, sex, cytogenetics, and bone marrow status at the time of RT had no significant effect on CR. Younger age (<50 y, P = 0.06), BMT prior to RT (P = 0.05), and underlying AML (P = 0.05) were marginally associated with higher CR to RT.
Our results indicate that a modest RT dose (20-30 Gy) achieves good local control of MS. Age, previous BMT, and underlying hematologic disease can affect RT response.
PMCID: PMC4016483  PMID: 24148102
Chloroma; Granulocytic sarcoma; Myeloid sarcoma; Extramedullary leukemia; Radiotherapy
3.  14-3-3ζ Overexpression Defines High Risk for Breast Cancer Recurrence and Promotes Cancer Cell Survival 
Cancer research  2009;69(8):3425-3432.
The ubiquitously expressed 14-3-3 proteins are involved in numerous important cellular functions. The loss of 14-3-3σ is a common event in breast cancer; however, the role of other 14-3-3s in breast cancer is unclear. Recently, we found that 14-3-3ζ overexpression occurs in early stage breast diseases and contributes to transformation of human mammary epithelial cells. Here, we show that 14-3-3ζ overexpression also persisted in invasive ductal carcinoma and contributed to the further progression of breast cancer. To examine the clinical impact of 14-3-3ζ overexpression in advanced stage breast cancer, we performed immunohistochemical analysis of 14-3-3ζ expression in primary breast carcinomas. 14-3-3ζ overexpression occurred in 42% of breast tumors and was determined to be an independent prognostic factor for reduced disease-free survival. 14-3-3ζ overexpression combined with ErbB2 overexpression and positive lymph node status identified a subgroup of patients at high risk for developing distant metastasis. To investigate whether 14-3-3ζ overexpression causally promotes breast cancer progression, we overexpressed 14-3-3ζ by stable transfection or reduced 14-3-3ζ expression by siRNA in cancer cell lines. Increased 14-3-3ζ expression enhanced anchorage independent growth and inhibited stress-induced apoptosis, whereas downregulation of 14-3-3ζ reduced anchorage independent growth and sensitized cells to stress-induced apoptosis via the mitochondrial apoptotic pathway. Transient blockade of 14-3-3ζ expression by siRNA in cancer cells effectively reduced the onset and growth of tumor xenografts in vivo. Therefore, 14-3-3ζ overexpression is a novel molecular marker for disease recurrence in breast cancer patients and may serve as an effective therapeutic target in patients whose tumors overexpress 14-3-3ζ.
PMCID: PMC2671640  PMID: 19318578
14-3-3ζ; breast cancer; apoptosis resistance; disease recurrence; prognostic marker

Results 1-3 (3)