Recycling of nutrient medium to improve productivity in large-scale microalgal culture using a hybrid electrochemical water treatment system.

Recycling and reusing of nutrient media in microalgal cultivation are important strategies to reduce water consumption and nutrient costs. However, these approaches have limitations, e.g., a decrease in biomass production, (because as reused media can inhibit biomass growth). To address these limitations, we applied a novel membrane filtration‒electrolysis‒ultraviolet hybrid water treatment method capable of laboratory-to-large-scale operation to increase biomass productivity and enable nutrient medium disinfection and recycling. In laboratory-scale experiments, electrolysis effectively remove the biological contaminants from the spent nutrient medium, resulting in a high on-site removal efficiency of dissolved organic carbon (DOC; 80.3 ± 5 %) and disinfection (99.5 ± 0.2 %). Compared to the results for the recycling of nutrient medium without water treatment, electrolysis resulted in a 1.5-fold increase in biomass production, which was attributable to the removal of biological inhibitors from electrochemically produced oxidants (mainly OCl-). In scaled-up applications, the hybrid system improved the quality of the recycled nutrient medium, with 85 ± 2 % turbidity removal, 75 ± 3 % DOC removal, and 99.5 ± 2 % disinfection efficiency, which was beneficial for biomass growth by removing biological inhibitors. After applying the hybrid water treatment method, we achieved a Spirulina biomass production of 0.47 ± 0.03 g L-1, similar to that obtained using a fresh medium (0.53 ± 0.02 g L-1). The on-site disinfection process described herein is practical and offers a cost-saving and environmental friendly alternative for nutrient medium recycling and reusing water in mass and sustainable cultivation of microalgae.

Yeast-Hydrolysate-Derived 1-Methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic Acid Inhibits Fat Accumulation during Adipocyte Differentiation.

This study aimed to investigate the impact of yeast hydrolysate (YH) on lipogenesis, elucidate its mechanistic action, and identify the active compounds responsible for its anti-adipogenic effects. YH (2 mg/mL) significantly reduced Oil Red O-stained lipids. YH (2 mg/mL) also downregulated C/EBPß and upregulated KLF2, both of which are early adipogenic factors. Moreover, YH (2 mg/mL) decreased C/EBPα, PPARγ, FABP4, FAS, ACC, and HMGCR mRNA expression. Additionally, YH significantly downregulated SEBP1c and SREBP2 and their target genes, which govern fatty acid and cholesterol metabolism; however, 2 mg/mL YH had a greater suppressive effect on SREBP1c than on SREBP2. YH (2 mg/mL) also significantly reduced the mRNA level of G6PD and malic enzyme, which are enzymes that synthesize NADPH for lipid synthesis, compared with the control. Furthermore, 1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid (MTCA) was identified as the active compound with anti-adipogenic effects using solvent fractionation and chromatographic analysis of YH, and 1.1 µg/mL MTCA significantly downregulated SREBP1c/SREBP2 mRNAs by 47.8% and 69.2%, respectively, along with the target genes FAS, ACC, and HMGCR by 79.0%, 77.0%, and 40.9%, respectively. Collectively, YH effectively suppressed adipogenic lipid storage by downregulating SREBP- and NADPH-synthesizing genes. These findings suggest that YH containing MTCA has the potential to act as an anti-obesity agent.

Primary Angiosarcoma of the Breast: A Single-Center Retrospective Study in Korea.

Due to the rarity of primary angiosarcoma of the breast, optimal management is based on expert opinion. The aim of this study was to review all primary angiosarcomas of the breast obtained from a single center in terms of clinicopathologic characteristics, treatment, and survival outcomes. From 1997 to 2020, 15 patients with primary angiosarcoma of the breast underwent either mastectomy or wide excision. We analyzed the clinicopathologic data to assess disease-free survival and overall survival. Fifteen women with primary angiosarcoma of the breast were identified. The mean age at diagnosis was 33 years (range: 14-63 years). The overall mean tumor size was 7.7 cm (range 3.5-20 cm). Upon histological grading, there were three cases of low grade, five intermediate grade, six high grade, and one unidentified grade. The five-year disease-free survival rate was 24.4%, and the five-year survival rate was 37.2%. The survival rate of the low-grade patient group was statistically higher than that of the intermediate- or high-grade patient groups (p = 0.024). Primary angiosarcoma of the breast is a rare aggressive tumor characterized by high grade and poor outcome. Histologic grade appears to be a reliable predictor of survival. There are no standard treatment guidelines; thus, optimal R0 surgical resection remains the best approach. The roles of neoadjuvant, adjuvant chemotherapy, and radiotherapy remain unclear.

Obesity and breast cancer risk for pre- and postmenopausal women among over 6 million Korean women.

PURPOSE: To examine the association between obesity measured by body mass index (BMI) and waist circumference (WC) according to menopausal status in Korean women. METHODS: We identified 6,467,388 women, using the Korean National Health Insurance System Cohort. Cox-proportional hazard models were used to generate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for breast cancer risk in relation to BMI and WC. RESULTS: In postmenopausal women, the risk of breast cancer increased with BMI. Compared to women with a BMI of 18.5-23 kg/m two, the risk of invasive breast cancer was lower in patients with BMI < 18.5 (aHR 0.82, 95% CI 0.75-0.89), while it increased linearly in those with BMI 23-25 (1.11, 1.08-1.14), BMI 25-30 (1.28, 1.25-1.32), and BMI ≥ 30 (1.54,1.47-1.62). In contrast, the risk of breast cancer decreased with BMI in premenopausal women. Compared to women with a BMI of 18.5-23, the risk of IBC was similar in those with a BMI < 18.5 (1.02, 0.94-1.11) and BMI 23-25 (1.01, 0.97-1.05), but was significantly lower in those with a BMI 25-30 (0.95, 0.91-0.98) and BMI ≥ 30 (0.90, 0.82-0.98). A relative increase with BMI was less profound for carcinoma in situ in postmenopausal women, and a relative decrease was more profound in premenopausal women. An analysis using WC showed almost identical results. CONCLUSIONS: There was a positive relationship between obesity and breast cancer in postmenopausal women, and an inverse association in premenopausal women.

A train the trainer program for healthcare professionals tasked with providing psychosocial support to breast cancer survivors.

BACKGROUND: The objective of this study is to develop, implement, and evaluate a training program for healthcare providers to improve ability to provide psychosocial support to breast cancer survivors in Korea. METHODS: Based on a needs assessment survey and in-depth interviews with breast cancer survivors, a multidisciplinary team developed two-day intensive training program as well as education materials and counseling notes. Participants' overall satisfaction was evaluated after the training. RESULTS: The training program included a total of 16 lectures held over the course of seven sessions. Forty-one nurses and 3 social workers participated in the training program. Mean age was 37.5(± 6.4) years, and on average, they had 11.1 (± 5.6) years of experience. Participants' overall satisfaction was good as following: program contents (4.04), trainee guidebook (3.82), location and environment (4.10), and program organization (4.19). Among the participants, 31 (70.4%) received certification after submitting real consultation cases after the training. CONCLUSION: Two day intensive training can provide a comprehensive and coordinated education to healthcare professionals for implementing survivorship care with an emphasis on psychosocial support. Furthermore, the program should resume as a periodic continuing education course for healthcare providers. Similar education for graduate students in oncology nursing would be beneficial.

Who are happy survivors? Physical, psychosocial, and spiritual factors associated with happiness of breast cancer survivors during the transition from cancer patient to survivor.

OBJECTIVE: This study aims to evaluate physical, psychosocial, and spiritual factors associated with happiness in breast cancer survivors during the reentry period. METHODS: It is a cross-sectional study with 283 nonmetastatic breast cancer survivors who completed treatment within 1 year. We included survivors who completed questionnaires on happiness and health-related quality of life (QoL) 2 years after cancer diagnosis. Happiness and QoL was measured using the Subjective Happiness Scale and EORTC QLQ-C30, respectively. Multivariable logistic regression was used to find factors associated with happiness. RESULTS: The mean age of the study participants was 48.5 ± 7.8 years. Among the 283 survivors, 14.5%, 43.8%, 32.5%, and 2.1% reported being "very happy," "happy," "neutral," and "not happy at all," respectively. Happy survivors reported a better general health status and QoL (67.6 vs 49.6; P < .01), and fewer symptoms compared to unhappy survivors. Happy survivors were more likely to feel certain about the future (27.2% vs 11.9%, P < .01), have a strong purpose in life (22.4% vs 9.3%, P < .01), and feel hopeful (36.4% vs 8.5%, P < .01) compared to unhappy survivors. In a multivariate model, having purpose (OR = 2.50, 95% CI 1.42-4.40) and hope (OR = 4.07, 95% CI 2.23-7.45) in life were found to be associated with happiness. CONCLUSIONS: During the reentry period, breast cancer survivors who are hopeful and have a clear purpose in life are more likely to be happy than those who are not. Setting proper life goals might be beneficial to help breast cancer survivors who experience persistent QoL issues.

Round block technique without cerclage in breast-conserving surgery.

BACKGROUND: Round block technique is a unique breast resection through periareolar doughnut incision. However, it is more technically challenging and time consuming. We simplified the procedure by exclusion of round block cerclage. The purpose of this study was to introduce our round block technique without cerclage and to evaluate the results of oncological and cosmetic outcomes. METHODS: A total of 92 patients with centrally located breast cancer were treated with breast-conserving surgery using round block technique at Samsung Medical Center from July 2009 to May 2012. All patients had a small breast defect with excised breast volume less than 20 % compared to the total breast volume. We minimized the extent of skin removal and used simple interrupted inverted intradermal sutures without cerclage in doughnut closure. Patient's cosmetic satisfaction was assessed by subjective questionnaires at least 6 months after the operation. RESULTS: The median size of tumors was 1.7 cm (range 0.5-5.0 cm). The average distance of the tumors from the nipple was 2.0 cm (range 0.0-4.0 cm) on sonogram and most of the tumors were located upper breast (82.6 %). The median operative time was 101.5 min (range 55-180), including axillary surgeries. Median follow-up was 12.0 months (range 2-36), and none of patients have developed local recurrence. Up to the longest 3 years of follow-up, favorable cosmetic results have been found in patients treated with round block technique. CONCLUSIONS: Round block without cerclage is technically easy and feasible for centrally located breast tumors with favorable cosmetic results.

Analysis of the effect of breast magnetic resonance imaging on the outcome in women undergoing breast conservation surgery with radiation therapy.

BACKGROUND: It remains uncertain whether MRI identification of additional foci of disease leads to improved outcome. We undertook a study to evaluate the influence of breast MRI on early and long-term outcome. METHODS: Among 1,271 patients undergone breast cancer surgery between January 2005 and December 2006, 785 patients were attempted for BCS. Operative approach and radiologic findings were compared according to MRI use. We reselected 615 patients with unilateral early-stage breast cancer treated with BCS including RT. We compared the histopathologic characteristics and outcomes according to MRI use. RESULTS: In patients attempted for BCS (n = 785), re-excision rates were not significantly different according to MRI use (P = 1.000). Conversion to mastectomy or bilateral cancer surgery were higher in MRI group (P = 0.002). The IBTR rate was higher in the non-MRI group (P = 0.020). Difference in contralateral cancer rate and total recurrence rates failed to reach statistical significance (P = 0.168, 0.383, respectively). Multivariate study after adjustment showed no difference in recurrence rates and IBTR rates between the two groups (hazard ratios 1.34, 6.37 Ps = 0.385, 0.076). CONCLUSION: Use of MRI in patients with early-stage breast cancer did not result in improvement of a patient's outcome.

Comparison between screen-detected and symptomatic breast cancers according to molecular subtypes.

Breast cancer screening programs make it possible to detect early cancer, thus reducing breast cancer mortality. We studied the clinicopathologic characteristics and prognosis of screen-detected invasive breast cancer compared with symptomatic breast cancer. And we compared the result according to molecular subtypes (luminal A, luminal B, Her2, and triple negative), with the goal of identifying the role of screening in each subtypes. From January 2002 to June 2008, 3,141 patients who underwent surgery for the treatment of invasive ductal carcinoma at Samsung Medical Center were included. Among them, 1,025 patients were screen-detected, and 2,116 patients who were screened over 2 years or never were symptomatic. We retrospectively reviewed the clinical and pathologic data. Screen-detected breast cancer was associated with older age, smaller tumor size, more hormone-receptor positive, less lymph node involvement, earlier stage, and reduced mortality compared with symptomatic breast cancer (P < 0.001). According to the molecular subtype, luminal A was most common (63.6%) and showed the most obvious survival benefit in screen-detected tumors in comparison with symptomatic tumors (5-year OS: 99.7 vs. 96.5%, 5-year DFS: 96.4 vs. 90.7%). Screen detection was independently associated with improved overall and disease-free survival outcomes after adjustment for covariates (HR 0.32, P = 0.035; HR 0.58, P = 0.020, respectively) only in the luminal A subtype. Differences in pathological features such as tumor size, nodal status, grade, and age at diagnosis with different molecular subtype distributions may explain the survival advantage of patients with screen-detected breast cancer. Screening programs seem to have a different efficacy depending on the molecular subtype of the breast cancer, especially in the luminal A subtype, for which screen detection acts as an independent prognostic factor itself.

Comparison of calcitriol versus cholecalciferol therapy in addition to oral calcium after total thyroidectomy with central neck lymph node dissection: a prospective randomized study.

BACKGROUND: The purpose of this study was to determine the effectiveness of oral calcium plus vitamin D supplementation and to compare the effects of cholecalciferol versus calcitriol treatments on postoperative hypocalcemia. METHODS: After total thyroidectomy with central neck dissection, 306 patients were divided into 4 groups according to "routine use versus on-demand use" and "cholecalciferol versus calcitriol." RESULTS: Hypocalcemic symptoms developed in 101 patients (33.0%). Hypocalcemia developed less frequently in patients receiving routine supplementation regardless of vitamin D type. However, routine supplementation did not prevent severe hypocalcemia. In patients receiving on-demand supplements, calcitriol was more effective and faster acting than was cholecalciferol. CONCLUSION: Routine oral calcium and vitamin D supplements are beneficial after total thyroidectomy with central neck lymph node dissection with no difference between cholecalciferol and calcitriol. If taken after the onset of hypocalcemia, however, calcitriol along with calcium carbonate seems to be more effective than is cholecalciferol with calcium carbonate.

Is robotic surgery superior to endoscopic and open surgeries in thyroid cancer?

BACKGROUND: Endoscopic thyroidectomies have been performed using various approaches, and indications have expanded with the development of new surgical techniques and instruments. Endoscopic thyroid surgery using bilateral axillo-breast approaches have excellent cosmetic results and a symmetrical, optimal operative view. However, because of the two-dimensional view and the nonflexible instruments, these approaches are not easy to use in performing a central lymph node dissection (CND). Robotic surgery has drawn attention as a potentially safe and effective method for treating thyroid cancer. The aim of the present study was to determine whether robotic surgery is superior to endoscopic and open surgery through comparing technical aspects and surgical outcomes. METHODS: From October 2008 to December 2009, 302 patients had total thyroidectomies and CND with cancer less than 1 cm. Patients were divided into three groups according to operation methods (open group; n = 138), (endo group; n = 95), (robot group; n = 69). RESULTS: Young patients preferred the robotic and endoscopic surgery. The number of retrieved lymph nodes in the open group (4.8 ± 2.8) was not different from the robot group (4.7 ± 2.7) and the endo group (4.6 ± 3.7). The operative time of the robot group was longer than the open and the endo group. The total drain amount in the robot group was more than the open and endo groups; however, there was no difference in the length of hospitalization and complication rates. There were no differences between the open (0.8 ± 2.0) and robot groups (0.8 ± 1.4), but the endo group (2.4 ± 6.3) showed higher postoperative serum thyroglobulin off thyroid hormone (Off-Tg) when compared to the open and robot groups. CONCLUSIONS: Robotic surgery was equal to open surgery except with respect to operative time and was superior to endoscopic surgery in Off-Tg levels presenting completeness of the operation in thyroid cancer surgery. Because it has excellent cosmetic results and various technical advantages, it should be considered in young, low-risk patients with thyroid carcinoma less than 1 cm.

Radioguided surgery using an intraoperative PET probe for tumor localization and verification of complete resection in differentiated thyroid cancer: a pilot study.

BACKGROUND: The major concerns in the surgical treatment of extensive or recurrent thyroid cancer include the difficulty of precise intraoperative and real-time tumor localization, the possibility of missing small metastatic lymph nodes during the operation, the need for reoperation due to recurrence, and complications. The usefulness and feasibility of an intraoperative PET probe have been reported for many other cancers; however, a standard, radioguided, operative protocol using a PET probe in thyroid cancer has not been established. The purpose of the current study was to evaluate the feasibility of an intraoperative PET probe with respect to precise tumor localization, verification of complete resection, and a decrease in unnecessary reoperations and complications. METHODS: This was a prospective, controlled study. Inclusion criteria were thyroid cancer requiring a total thyroidectomy with a modified radical neck dissection (MRND) and recurrent thyroid cancer after thyroid surgery. The types of procedures included total thyroidectomy with MRND, selective neck dissection (SND), and excision of recurrent thyroid masses. The PET probe NodeSeeker(®) is a high-energy gamma probe seeking 511 keV photons. Operative exploration was carried out between 2 and 6 h after injection of (18)F-FDG. The surgeon calculated the target-to-background ratio (T/B ratio) by checking the 10-sec accumulated count using the PET probe. We performed a re-exploration if the T/B ratio was >1.3 in the operative bed. RESULTS: Twelve patients underwent PET probe-guided operation. SNDs, mass excisions, total thyroidectomy with MRND, and MRND were performed on 7, 4, and 1 patient, respectively. All tumors were localized by the PET probe precisely in real time, and the lesions not observed on preoperative PET were detected by the PET probe in 7 patients. Furthermore, additional lymph nodes that were not identified on preoperative ultrasonography were detected in 1 patient. The mean T/B ratio of thyroid carcinoma was 1.51 ± 0.53 (range, 1.17-4.03) and the postoperative serum thyroglobulin off thyroid hormone was <2.0 ng/ml. CONCLUSION: Radioguided surgery using an intraoperative PET probe in thyroid cancer appears to be a useful method for real-time tumor localization, verification of complete excision, and minimization of the possibility of residual cancer. Therefore, an intraoperative PET probe in thyroid cancer may decrease unnecessary reoperations and complications due to persistent disease.

Temperature gradient interaction chromatography of polymers: A molecular statistical model.

A new model describing the retention in temperature gradient interaction chromatography of polymers is developed. The model predicts that polymers might elute in temperature gradient interaction chromatography in either an increasing or decreasing order or even nearly independent of molar mass, depending on the rate of the temperature increase relative to the flow rate. This is in contrast to solvent gradient elution, where polymers elute either in order of increasing molar mass or molar mass independent. The predictions of the newly developed model were verified with the literature data as well as new experimental data.

12-O-Tetradecanoyl phorbol-13-acetate (TPA)-induced growth arrest is increased by silibinin by the down-regulation of cyclin B1 and cdc2 and the up-regulation of p21 expression in MDA-MB231 human breast cancer cells.

TPA is a potent regulator of cell growth, including cell proliferation and differentiation. In this study, we determined the effect of silibinin on TPA-induced growth arrest in breast cancer cells. Silibinin increased growth arrest of the G2/M phase in a dose-dependent fashion. Silibinin decreased the basal level of cyclin B1 and cdc2 expression, which is involved in S phase and G2/M transition. In addition, TPA-induced G2/M phase arrest was increased by silibinin. Under the same conditions, TPA-induced down-regulation of cyclin B1 and cdc2 was decreased by silibinin. In contrast, TPA-induced p21 expression was further increased by silibinin. To determine the regulatory mechanism of TPA-induced growth arrest, we pretreated cells with various inhibitors, such as UO126, SB203580, and LY294002. Interestingly, TPA-induced growth arrest was significantly increased by LY294002, but not by UO126 and SB203580. In addition, TPA-induced down-regulation of cyclin B1 was inhibited by LY294002; however, the basal level of p21 was increased by TPA and TPA-induced p21 expression was further increased by LY294002. Finally, adenoviral constitutively active-Akt (Ad-CA-Akt) overexpression regulated the up-regulation of cyclin B1 and the down-regulation of p21. Therefore, we have demonstrated that silibinin has an additive effect on TPA-induced growth arrest through the PI-3-kinase/Akt-dependent pathway.

Effect of film thickness on the phase behaviors of diblock copolymer thin film.

A phase diagram was constructed for a polystyrene-block-polyisoprene (PS-b-PI, M(W) = 32 700, f(PI) = 0.670) in thin films on Si wafer as a function of film thickness over the range of 150-2410 nm (7-107L(0) (L(0): domain spacing)). The PS-b-PI exhibits a variety of ordered phases from hexagonally perforated lamellar (HPL) via double gyroid (DG) to hexagonally packed cylinder (HEX) before going to the disordered (DIS) phase upon heating. The morphology of the PS-b-PI in thin film was investigated by grazing incidence small-angle X-ray scattering, transmission electron microscopy, and transmission electron microtomography. In thin film, the phase transition temperature is difficult to be determined unequivocally with in situ heating processes since the phase transition is slow and two phases coexist over a wide temperature range. Therefore, in an effort to find an "equilibrium" phase, we determined the long-term stable phase formed after cooling the film from the DIS phase to a target temperature and annealing for 24 h at the temperature. The temperature windows of stable ordered phases are strongly influenced by the film thickness. As the film thickness decreases, the temperature window of layer-like structures such as HPL and HEX becomes wider, whereas that of the DG stable region decreases. For the films thinner than 160 nm (8L(0)), only the HPL phase was found. In the films exhibiting DG phase, a perforated layer structure at the free surface was found, which gradually converts to the internal DG structure. The relief of interfacial tension by preferential wetting appears to play an important role in controlling the morphology in very thin films.

Does pre-operative breast magnetic resonance imaging in addition to mammography and breast ultrasonography change the operative management of breast carcinoma?

Magnetic resonance imaging (MRI) has been used for the local staging of breast cancer, especially to determine the extent of multiple lesions and to identify occult malignancies. The aim of this study was to evaluate the effect of pre-operative MRI on the surgical treatment of breast cancer. Between January 2006 and May 2007, 535 newly diagnosed breast cancer patients who planned to undergo breast conserving surgery had clinical examinations, bilateral mammography, breast ultrasonography, and breast MRI. The radiologic findings and clinicopathologic data were reviewed retrospectively. Ninety-eight (18.3%) patients had additional lesions, shown as suspicious lesions on breast MRI, but not detected with conventional methods. Eighty-four (15.7%) of these patients had a change in surgical treatment plans based on the MRI results. Forty-seven (8.8%) of the 84 patients had additional malignancies;the other 37 patients (6.9%) had benign lesions. The positive predictive value for MRI-based surgery was 56.0% (47 of 84 patients). During the period of study, the use of pre-operative MRI was increased with time (OR 1.20; 95% CI 1.16-1.23; P < 0.001), but the mastectomy rate did not change significantly (OR 0.98; 95% CI 0.95-1.00; P = 0.059). Multiple factors were analyzed to identify the patients more likely to undergo appropriate and complete surgery based on the additional findings of the pre-operative MRI, but the results were not statistically significant. This research suggests that a pre-operative MRI can potentially lower the rate of incompletely excised malignancies by identifying additional occult cancer prior to surgery and does not lead to an increase in the mastectomy rate; however, because some benign lesions are indistinguishable from suspicious or malignant lesions, excessive surgical procedures are unnecessarily performed in a significant portion of patients. In the future, the criteria for the use of MRI in local staging of breast cancer should be established.

Silibinin prevents TPA-induced MMP-9 expression by down-regulation of COX-2 in human breast cancer cells.

ETHNOPHARMACOLOGICAL RELEVANCE: The expression of matrix metalloproteinase-9 (MMP-9) and cyclooxygenase-2 (COX-2) are pivotal steps in breast cancer pathogenesis. In a previous study, we reported that silibinin suppresses TPA-induced MMP-9 expression through the Raf/MEK/ERK pathway. AIMS OF THE STUDY: Herein we determined the co-relationship between MMP-9 and COX-2, as well as the effect of silibinin on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and COX-2 expression in the human breast cancer cells, MCF-7 and MDA-MB231. METHODS: The toxicity of silibinin was evaluated by Quick Cell Proliferation Assay Kit II. MMP-9 and COX-2 expression were analyzed by Zymography and Western blotting, respectively. Adenoviral constitutively active (CA)-MEK was used to activate MEK/ERK pathway. RESULTS: The expression of MMP-9 and COX-2 in response to TPA was increased, whereas TPA-induced MMP-9 and COX-2 expression was decreased by silibinin. Our results showed that TPA-induced MMP-9 expression was inhibited by celecoxib in a dose-dependent fashion, but not MMP-1-expression. Both MMP-9 and COX-2 expression were significantly increased by CA-MEK overexpression. In contrast, TPA-induced MMP-9 and COX-2 expression was decreased by UO126 (MEK 1/2 inhibitor). CONCLUSION: Silibinin down-regulates TPA-induced MMP-9 expression through inhibition of COX-2 expression in breast cancer cells.

EGF-induced MMP-9 expression is mediated by the JAK3/ERK pathway, but not by the JAK3/STAT-3 pathway in a SKBR3 breast cancer cell line.

The number of epidermal growth factor receptors (EGFRs) and their ligands are highly expressed in malignant tumor cells. The EGF signaling pathway is also activated in up to one-third of patients with breast cancer. In this study, we investigated the novel function of the JAK3 inhibitor, WHI-P131, on EGF-induced MMP-9 expression and the regulatory mechanism of EGF-induced MMP-9 expression in SKBR3 cells. We observed that EGF increased MMP-9 mRNA and protein expression in a dose-dependent manner. EGF also induced the phosphorylation of EGFR, ERK, and STAT-3, and these effects were inhibited by the EGFR inhibitor, AG1478.To investigate the involvement of the STAT-3 pathway on EGF-induced MMP-9 expression, we pretreatedSKBR3 cells with JAK1, JAK2, and JAK3 inhibitors prior to EGF treatment. The results showed that the JAK3 inhibitor, WHI-P131, as well as JAK3 siRNA transfection, but not the JAK1 and JAK2 inhibitors, significantly decreased EGF-induced MMP-9 expression. In addition, EGF-induced STAT-3 phosphorylation was only inhibited by WHI-P131. We then transfected cells with adenoviral STAT-3 (Ad-STAT-3), followed by treatment with EGF. Interestingly, EGF-induced MMP-9 expression was decreased by Ad-STAT-3 overexpression in a dose-dependent manner, while it was significantly increased by STAT-3 siRNA transfection. Our results also showed that basal levels of MMP-9 expression were significantly increased by constitutive active-MEK (CAMEK)overexpression. EGF-induced ERK phosphorylation was prevented by WHI-P131, but not by JAK1 andJAK2 inhibitors. On the other hand, EGF-induced MMP-9 expression was decreased by the MEK1/2 inhibitor,UO126. Therefore, for the first time, we suggest that the JAK3 inhibitor, WHI-P131, inhibits EGF-induced STAT-3 phosphorylation as well as ERK phosphorylation. The JAK3/ERK pathway may play an important role in EGFinduced MMP-9 expression in SKBR3 cells.

Two-dimensional liquid chromatography analysis of synthetic polymers using fast size exclusion chromatography at high column temperature.

In recent years, two-dimensional liquid chromatography (2D-LC) has been used increasingly for the analysis of synthetic polymers. A 2D-LC analysis provides richer information than a single chromatography analysis at the cost of longer analysis time. The time required for a comprehensive 2D-LC analysis is essentially proportional to the analysis time of the second dimension separation. Many of 2D-LC analyses of synthetic polymers have employed size exclusion chromatography (SEC) for the second-dimension analysis due to the relatively short analysis time in addition to the wide use in the polymer analysis. Nonetheless, short SEC columns are often used for 2D-LC analyses to reduce the separation time, which inevitably deteriorates the resolution. In this study, we demonstrated that high temperature SEC can be employed as an efficient second-LC in the 2D-LC separation of synthetic polymers. By virtue of high temperature operation (low solvent viscosity and high diffusivity of the polymer molecules), a normal length SEC column can be used at high flow rate with little loss in resolution.

Silibinin prevents TPA-induced MMP-9 expression and VEGF secretion by inactivation of the Raf/MEK/ERK pathway in MCF-7 human breast cancer cells.

Matrix metalloproteinase-9 (MMP-9) and vascular endothelial growth factor (VEGF) expression are pivotal steps in cancer metastasis. Herein, we investigated the effect of silibinin, a major constituent (flavanolignan) of the fruits of Silybum marianum, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and VEGF expression in MCF-7 human breast cancer cells. The expression of MMP-9 and VEGF in response to TPA was increased, whereas TPA-induced MMP-9 and VEGF expression was decreased by silibinin. To investigate the regulatory mechanism of silibinin on TPA-induced MMP-9 and VEGF expression, we pretreated cells with various inhibitors, such as UO126 (MEK1/2 inhibitor), SP600125 (JNK inhibitor), and SB203580 (p38 inhibitor). Interestingly, TPA-induced MMP-9 expression was significantly inhibited by UO126, but not by SP600125 and SB203580. In addition, we pretreated cells with 100 microM silibinin prior to TPA treatment. TPA-induced MEK and ERK phosphorylation was significantly decreased by silibinin in MCF7 cells. TPA-induced VEGF expression was also suppressed by UO126. On the other hand, we found that adenoviral constitutive active-MEK (Ad-CA-MEK) significantly increased MMP-9 and VEGF expression. Taken together, we suggest that the inhibition of TPA-induced MMP-9 and VEGF expression by silibinin is mediated by the suppression of the Raf/MEK/ERK pathway in MCF-7 breast cancer cells.