Soohyeon Lee

Continuous separation of breast cancer cells from blood samples using multi-orifice flow fractionation (MOFF) and dielectrophoresis (DEP)

Circulating tumor cells (CTCs) are highly correlated with the invasive behavior of cancer, so their isolations and quantifications are important for biomedical applications such as cancer prognosis and measuring the responses to drug treatments. In this paper, we present the development of a microfluidic device for the separation of CTCs from blood cells based on the physical properties of cells. For use as a CTC model, we successfully separated human breast cancer cells (MCF-7) from a spiked blood cell sample by combining multi-orifice flow fractionation (MOFF) and dielectrophoretic (DEP) cell separation technique. Hydrodynamic separation takes advantage of the massive and high-throughput filtration of blood cells as it can accommodate a very high flow rate. DEP separation plays a role in precise post-processing to enhance the efficiency of the separation. The serial combination of these two different sorting techniques enabled high-speed continuous flow-through separation without labeling. We observed up to a 162-fold increase in MCF-7 cells at a 126 µL min(-1) flow rate. Red and white blood cells were efficiently removed with separation efficiencies of 99.24% and 94.23% respectively. Therefore, we suggest that our system could be used for separation and detection of CTCs from blood cells for biomedical applications.

Phase III, Multicenter, Randomized Trial of Maintenance Chemotherapy Versus Observation in Patients With Metastatic Breast Cancer After Achieving Disease Control With Six Cycles of Gemcitabine Plus Paclitaxel As First-Line Chemotherapy: KCSG-BR07-02

PURPOSE The primary purpose of our study was to evaluate whether maintenance chemotherapy with paclitaxel/gemcitabine (PG) was superior to observation in improving progression-free survival (PFS) in patients with metastatic breast cancer (MBC) who achieved disease control with an initial six cycles of PG as their first-line treatment. PATIENTS AND METHODS The study was a prospective, randomized, multicenter, phase III trial. Patients MBC with who achieved disease control after six cycles of PG chemotherapy were randomly assigned to maintenance chemotherapy or observation until progression. RESULTS Of 324 patients from 10 centers enrolled, 231 patients with MBC exhibited disease control (complete response + partial response + stable disease) with first-line PG and were randomly assigned to maintenance chemotherapy (n = 116) or observation (n = 115). The median age was 48 years (range, 28 to 76 years), median follow-up was 33 months, and median number of chemotherapy cycles in the maintenance group after random assignment was six. The median PFS time after random assignment was longer in the maintenance group than in the observation group (7.5 v 3.8 months, respectively; P = .026). The median overall survival (OS) time was longer in the maintenance group than in the observation group (32.3 v 23.5 months, respectively; P = .047). The rate of grade 3 or higher neutropenia after random assignment was higher in the maintenance group than in the observation group (61% v 0.9%, respectively; P < .001). CONCLUSION In patients with MBC who achieved disease control with an initial six cycles of PG chemotherapy, maintenance PG chemotherapy resulted in better PFS and OS compared with observation.

Prognostic impact of FOXP3 expression in triple-negative breast cancer

Abstract Background. Forkhead Box Protein 3 (FOXP3) is a marker for immunosuppressive CD4+CD25+ regulatory T cells (Tregs). We investigated whether there were significant numbers of FOXP3-positive Tregs in triple-negative breast cancer (TNBC) using immunohistochemistry, and whether the presence of FOXP3-positive Tregs was associated with other prognostic factors, such as stage or histologic grade. We investigated the number of tumor-infiltrating FOXP3-positive Tregs in formalin-fixed TNBC specimens obtained from patients who received palliative treatment between 1999 and 2007. Material and methods. Immunohistochemistry was used to assess the number of CD4+, CD25+, and FOXP3+ Tregs in tumor tissue and normal breast tissue from 86 TNBC patients. Univariate and multivariate analyses evaluated outcomes according to the number of FOXP3-positive Tregs. Results. Of the 86 tumor specimens, 22 (25.6%) expressed more than 15 FOXP3-positive Tregs per 10 high power fields in the peritumoral area. On multivariate analysis, staining showing ≥ 15 FOXP3-positive Tregs was an independent prognostic factor for overall survival and progression free survival with hazard ratios of 2.4 (95% CI 1.0–5.6; p = 0.049) and 2.0 (95% CI 1.1–3.6; p = 0.032), respectively. In TNBC, FOXP3-positive Tregs had stronger prognostic significance than did FOXP3-negative Tregs. The finding of improved survival associated with highly infiltrating FOXP3-positive Tregs in TNBC contrasted with several other types of solid cancer. Conclusion. TNBC may be differently driven by FOXP3 via an immune mechanism. The inclusion of FOXP3+ Tregs may help to improve prognostication for TNBC.

Post-traumatic arterial priapism: Colour Doppler examination and superselective arterial embolization

Purpose : To evaluate selective embolization for management of post-traumatic priapism and colour Doppler sonography for the diagnosis of the causative lesion and for planning embolization. Materials and Methods : Six male patients with post-traumatic priapism underwent selective angiography and embolization. Colour Doppler sonography with grey-scale was performed in all six patients before angiography. Results : Selective angiography showed intracavernosal arteriovenous fistulas in all patients and pseudoaneurysm of the cavernosal artery (or common penile artery) in three patients. After successful embolization, detumescence was achieved in all patients. Colour Doppler sonography enabled localization and characterization of the lesion causing priapism in four patients. Grey-scale ultrasonography showed the dilated cavernosal sinuses in all patients. Conclusion : Angiography with selective embolization is safe and effective method to correct post-traumatic priapism. Colour Doppler sonography with grey scale is a useful preangiographic study, as it allows for characterization and localization of the causative lesion except lesions at the proximal cavernosal or distal penile artery near the symphysis pubis.

Anaplastic Lymphoma Kinase Gene Copy Number Gain in Inflammatory Breast Cancer (IBC): Prevalence, Clinicopathologic Features and Prognostic Implication

Background Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer, and its molecular pathogenesis still remains to be elucidated. This study aimed to evaluate the prevalence and implication of anaplastic lymphoma kinase (ALK) copy number change in IBC patients. Methods We retrospectively collected formalin-fixed, paraffin-embedded tumor tissues and medical records of IBC patients from several institutes in Korea. ALK gene copy number change and rearrangement were assessed by fluorescence in situ hybridization (FISH) assay, and ALK expression status was evaluated by immunohistochemical (IHC) staining. Results Thirty-six IBC patients including those with HER2 (+) breast cancer (16/36, 44.4%) and triple-negative breast cancer (13/36, 36.1%) were enrolled in this study. ALK copy number gain (CNG) was observed in 47.2% (17/36) of patients, including one patient who harbored ALK gene amplification. ALK CNG (+) patients showed significantly worse overall survival compared to ALK CNG (-) patients in univariate analysis (24.9 months vs. 38.1 months, p = 0.033). Recurrence free survival (RFS) after curative mastectomy was also significantly shorter in ALK CNG (+) patients than in ALK CNG (-) patients (n = 22, 12.7 months vs. 43.3 months, p = 0.016). Multivariate Cox regression analysis with adjustment for HER2 and ER statuses showed significantly poorer RFS for ALK CNG (+) patients (HR 5.63, 95% CI 1.11–28.44, p = 0.037). Conclusion This study shows a significant presence of ALK CNG in IBC patients, and ALK CNG was associated with significantly poorer RFS.

FOXP3 Expression Is Related to High Ki-67 Index and Poor Prognosis in Lymph Node-Positive Breast Cancer Patients

Background: Recent preclinical studies have shown that Forkhead box protein 3 (FOXP3) is an important tumor suppressor gene. The clinical and prognostic implication of FOXP3 expression in breast cancer cells still remains controversial. Methods: We evaluated the FOXP3 expression status of 183 patients who underwent curative surgery for breast cancer using the immunohistochemical assay of tissue microarray. Results: We found FOXP3 expression in 51 out of 183 (27.9%) surgically resected breast cancer tumors, and 33 patients were scored as weak positive and 18 as strong positive. FOXP3-positive tumors were associated with significantly higher nuclear grade, higher histologic grade and a more negative estrogen receptor status. The FOXP3 expression level was independently associated with high Ki-67 index in a logistic regression model. In the node-positive subgroup, strong FOXP3 positivity was related to poor disease-free survival and disease-specific survival compared to FOXP3-negative patients, whereas there was no survival difference between FOXP3-negative and FOXP3-weak-positive patients. Multivariate analysis with adjustment for patient age and human epidermal growth factor receptor 2 status demonstrated significantly poor survival of FOXP3-strong-positive patients in node-positive patients. Conclusion: Our results suggest that strong FOXP3 expression in breast cancer cells is associated with poor prognosis and high Ki-67 index.

Prediction of outcomes for patients with brain parenchymal metastases from breast cancer (BC): a new BC-specific prognostic model and a nomogram

The purpose of this study is to validate the recently published Breast-Graded Prognostic Assessment (GPA) and propose a new prognostic model and nomogram for patients with brain parenchymal metastases (BM) from breast cancer (BC). We retrospectively investigated 171 consecutive patients who received a diagnosis of BM from BC during 2000-2008. We appraised the recently proposed Sperdutos BC-specific GPA in training cohort through Kaplan-Meier survival curve using log-rank test and area under the curve for the BC-GPA predicting overall survival at 1 year and developed a new nomogram to predict outcomes using multivariate Cox-regression analysis. By putting the Sperdutos Breast-GPA together with our nomogram, we developed a new prognostic model. We validated our new prognostic model with an independent external patient cohort from 2 institutes for the same period. On the basis of our Cox-regression analysis, therapeutic effect of trastuzumab and status of extracranial systemic disease control were incorporated into our new prognostic model in addition to Karnofsky performance status, age, and hormonal status. Our new prognostic model showed significant discrimination in median survival time, with 3.7 months for class I (n = 15), 7.8 months for class II (n = 82), 10.7 months for class III (n = 42), and 19.2 months for class IV (n = 32; P < .0001). The new prognostic model accurately predicted survival among patients with BC from BM in an external validation cohort (P < .0001). We propose a new prognostic model and a nomogram reflecting the different biological features of BC, including treatment effect and status of extracranial disease control, which was excellently validated in an independent external cohort.

Treatment of recurrent hepatocellular carcinoma after liver transplantation

Aim:  Liver transplantation (LT) is a curative treatment for localized hepatocellular carcinoma (HCC), but the recurrence rate after LT is about 10–20%, with a dismal prognosis. Little data exist as to the natural history, treatment outcome and optimal treatment of recurrent HCC after LT. We reviewed various treatment modalities given to patients with recurrent HCC after LT.

Extraosseous osteosarcoma: Single institutional experience in Korea

Aim:  Extraosseous osteosarcoma (EOO) is a rare soft tissue form of osteosarcoma without involvement of the skeletal system. Due to the rarity of disease, its clinical features and optimal treatment are yet to be defined.

Psychosocial Impact of Cancer Patients on Their Family Members

Purpose A population-based study was conducted in order to examine the characteristics of family members of cancer patients in comparison with the general population and also to evaluate the psychosocial impact of cancer patients on their family members. Materials and Methods From the Fourth Korea National Health and Nutrition Examination Surveys (KNHANES IV) (2007-2009) dataset, we identified 460 cancer patients and then selected family members of these patients who were aged 20 years or older (n=565). The control group was sampled from members of families without a cancer patient with matching for sex and age (n=2,260). Serial conditional logistic regression models were used for comparison of characteristics between family members of cancer patients and subjects in the control group. Results Family members of cancer patients were less employed (57.9% vs. 63.0%, p<0.001), more functionally limited (20.2% vs. 16.5%, p=0.032), and had lower self-rated health (p=0.023) compared with sex and age-matched control subjects. They also had a significantly higher level of stress (79.7% vs. 76.1%, p=0.008), history of depression (12.9% vs. 10.2%, p=0.035), and current depressive symptoms (5.5% vs. 3.5%, p=0.038). However, higher physical activity was reported in family members of cancer patients (13.6% vs. 9.6%, p=0.003) than in control subjects. The presence of a cancer patient in the family showed an association with current depressive symptoms (odds ratio, 1.62; 95% confidence interval, 1.05 to 2.48; p=0.028), however, the association was no longer significant after adjustment for household income, education level, and employment status (p=0.304). Conclusion Family members of cancer patients are more susceptible to depression, probably due to adverse change in socioeconomic status. Use of multidisciplinary approaches for promotion of psychological health and well-being is essential.