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1.
Biomed Rep ; 20(1): 4, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38124767

ABSTRACT

Nutmeg is the seed derived from Myristica fragrans. Nutmeg seeds contain alkylbenzene derivatives such as myristicin, which are toxic to the human organism, and lignan compounds such as nectandrin B, which possess anti-aging and anti-diabetic properties. However, the anti-adipogenic, prolipolytic and anti-inflammatory effects of lignan-enriched nutmeg extract (LNX) on preadipocytes remain unclear. In the present study, the effects of LNX on lipid accumulation, glycerol release and inflammatory cyclooxygenase-2 (COX-2) expression in differentiated 3T3-L1 preadipocytes were investigated. Oil red O staining demonstrated that treatment with LNX resulted in a concentration-dependent reduction in lipid accumulation in differentiating 3T3-L1 preadipocytes without affecting cell growth. Mechanistically, LNX treatment at 6 µg/ml led to a reduction in phosphorylation levels of signal transducer and activator of transcription 3 (STAT3), whereas it did not influence the peroxisome proliferator-activated receptor gamma (PPAR-γ) and CCAAT enhancer binding protein alpha (C/EBP-α) expression levels during 3T3-L1 preadipocyte differentiation. In addition, LNX treatment at 6 µg/ml led to a decrease in fatty acid synthase (FAS) expression levels on day (D) 2, but not D5 and D8, during preadipocyte differentiation. Treatment with LNX at 6 µg/ml did not affect the expression levels of perilipin A during preadipocyte differentiation. In differentiated 3T3-L1 adipocytes, LNX treatment at 6 µg/ml did not stimulate glycerol release and hormone-sensitive lipase phosphorylation, which are known lipolysis hallmarks. Furthermore, LNX treatment at the doses tested had no effect on tumor necrosis factor alpha-induced COX-2 expression in 3T3-L1 preadipocytes. Collectively, these results demonstrated that LNX has an anti-adipogenic effect on differentiating 3T3-L1 preadipocytes, which is mediated by the downregulation of STAT3 phosphorylation and FAS expression.

2.
ACS Nano ; 17(3): 2629-2638, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36688595

ABSTRACT

Vertical type II van der Waals heterobilayers of transition metal dichalcogenides (TMDs) have attracted wide attention due to their distinctive features mostly arising from the emergence of intriguing electronic structures that include moiré-related phenomena. Owing to strong spin-orbit coupling under a noncentrosymmetric environment, TMD heterobilayers host nonequivalent +K and -K valleys of contrasting Berry curvatures, which can be optically controlled by the helicity of optical excitation. The corresponding valley selection rules are well established by not only intralayer excitons but also interlayer excitons. Quite intriguingly, here, we experimentally demonstrate that unusual valley switching can be achieved using the lowest-lying intralayer excitons in H-type heterobilayer WS2/MoS2 prepared by one-step growth. This TMD combination provides an ideal case for interlayer coupling with an almost perfect lattice match, thereby also in the momentum space between +K and -K valleys in the H-type heterostructure. The underlying valley-switching mechanism can be understood by bright-to-dark conversion of initially created electrons in the valley of WS2, followed by interlayer charge transfer to the opposite valley in MoS2. Our suggested model is also confirmed by the absence of valley switching when the lowest-lying excitons in MoS2 are directly generated in the heterobilayer. In contrast to the H-type case, we show that no valley switching is observed from R-type heterobilayers prepared by the same method, where interlayer charge transfer does not occur between the opposite valleys. We compare the case with the series of valley polarization data from other heterobilayer combinations obtained under different excitation energies and temperatures. Our valley switching mechanism can be utilized for valley manipulation by controlling the excitation photon energy together with the photon helicity in valleytronic devices derived from H-type TMD heterobilayers.

3.
Nat Commun ; 12(1): 6453, 2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34753923

ABSTRACT

Anisotropic triangular antiferromagnets can host two primary spin excitations, namely, spinons and triplons. Here, we utilize polarization-resolved Raman spectroscopy to assess the statistics and dynamics of spinons in Ca3ReO5Cl2. We observe a magnetic Raman continuum consisting of one- and two-pair spinon-antispinon excitations as well as triplon excitations. The twofold rotational symmetry of the spinon and triplon excitations are distinct from magnons. The strong thermal evolution of spinon scattering is compatible with the bosonic spinon scenario. The quasilinear spinon hardening with decreasing temperature is envisaged as the ordering of one-dimensional topological defects. This discovery will enable a fundamental understanding of novel phenomena induced by lowering spatial dimensionality in quantum spin systems.

4.
ACS Appl Mater Interfaces ; 13(48): 57588-57596, 2021 Dec 08.
Article in English | MEDLINE | ID: mdl-34797625

ABSTRACT

Noncentrosymmetric transition-metal dichalcogenides, particularly their 3R polymorphs, provide a robust setting for valleytronics. Here, we report on the selective growth of monolayers and bilayers of MoS2, which were acquired from two closely but differently oriented substrates in a chemical vapor deposition reactor. It turns out that as-grown bilayers are predominantly 3R-type, not more common 2H-type, as verified by microscopic and spectroscopic characterization. As expected, the 3R bilayer showed a significantly higher valley polarization compared with the centrosymmetric 2H bilayer, which undergoes efficient interlayer scattering across contrasting valleys because of their vertical alignment of the K and K' points in momentum space. Interestingly, the 3R bilayer showed even higher valley polarization compared with the monolayer counterpart. Moreover, the 3R bilayer reasonably maintained its valley efficiency over a very wide range of excitation power density from ∼0.16 kW/cm2 to ∼0.16 MW/cm2 at both low and room temperatures. These observations are rather surprising because valley dephasing could be more efficient in the bilayer via both interlayer and intralayer scatterings, whereas only intralayer scattering is allowed in the monolayer. The improved valley polarization of the 3R bilayer can be attributed to its indirect-gap nature, where valley-polarized excitons can relax into the valley-insensitive band edge, which otherwise scatter into the contrasting valley to effectively cancel out the initial valley polarization. Our results provide a facile route for the growth of 3R-MoS2 bilayers that could be utilized as a platform for advancing valleytronics.

5.
Sci Rep ; 11(1): 21202, 2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34707186

ABSTRACT

Gallium Telluride (GaTe), a layered material with monoclinic crystal structure, has recently attracted a lot of attention due to its unique physical properties and potential applications for angle-resolved photonics and electronics, where optical anisotropies are important. Despite a few reports on the in-plane anisotropies of GaTe, a comprehensive understanding of them remained unsatisfactory to date. In this work, we investigated thickness-dependent in-plane anisotropies of the 13 Raman-active modes and one Raman-inactive mode of GaTe by using angle-resolved polarized Raman spectroscopy, under both parallel and perpendicular polarization configurations in the spectral range from 20 to 300 cm-1. Raman modes of GaTe revealed distinctly different thickness-dependent anisotropies in parallel polarization configuration while nearly unchanged for the perpendicular configuration. Especially, three Ag modes at 40.2 ([Formula: see text]), 152.5 ([Formula: see text]), and 283.8 ([Formula: see text]) cm-1 exhibited an evident variation in anisotropic behavior as decreasing thickness down to 9 nm. The observed anisotropies were thoroughly explained by adopting the calculated interference effect and the semiclassical complex Raman tensor analysis.

6.
Sci Rep ; 11(1): 7843, 2021 Apr 12.
Article in English | MEDLINE | ID: mdl-33846520

ABSTRACT

Van der Waals (vdW) heterostructures, consisting of a variety of low-dimensional materials, have great potential use in the design of a wide range of functional devices thanks to their atomically thin body and strong electrostatic tunability. Here, we demonstrate multi-functional indium selenide (InSe)/black phosphorous (BP) heterostructures encapsulated by hexagonal boron nitride. At a positive drain bias (VD), applied on the BP while the InSe is grounded, our heterostructures show an intermediate gate voltage (VBG) regime where the current hardly changes, working as a ternary transistor. By contrast, at a negative VD, the device shows strong negative differential transconductance characteristics; the peak current increases up to ~5 µA and the peak-to-valley current ratio reaches 1600 at VD = -2 V. Four-terminal measurements were performed on each layer, allowing us to separate the contributions of contact resistances and channel resistance. Moreover, multiple devices with different device structures and contacts were investigated, providing insight into the operation principle and performance optimization. We systematically investigated the influence of contact resistances, heterojunction resistance, channel resistance, and the thickness of BP on the detailed operational characteristics at different VD and VBG regimes.

7.
Article in English | MEDLINE | ID: mdl-33466893

ABSTRACT

BACKGROUND: The demand for implementing a new listing scheme to expedite patient access to novel oncology drugs has increased in South Korea. This study was conducted to compare the prices of anticancer drugs between eight countries and to explore the feasibility of a 'pre-listing and post-evaluation' scheme to expedite patient access to oncology drugs. METHODS: This study included 34 anticancer drugs, which were reimbursed between 1 January 2007 and 31 December 2017. The unit price and sales volume of the study drugs were collected from eight countries and IQVIA data, respectively. The prices were adjusted to estimate the ex-factory prices using the discount/rebate rate suggested by the Health Insurance Review Agency (HIRA). The four price indices of Laspeyres, Paasche, Fisher, and the unweighted index were calculated using the price in each country, the average price, and lowest price among the study countries. Each currency was converted using the currency exchange rate and purchasing power parity (PPP). The budget impact of implementing the proposed pre-listing and post-evaluation scheme on payers was calculated. RESULTS: Based on the currency exchange rate, anticancer drug prices were higher in other countries (index range: 1.05-2.78) compared to Korea. The prices in Korea were similar to countries with the lowest prices. When the PPP was applied, prices were higher in the US, Germany, Italy, and Japan than in Korea (range: 1.10-2.13); however, the prices were lower in the UK, France, and Switzerland than in Korea (range: 0.72-0.99). The financial burden of implementing the pre-listing and post-evaluation scheme was calculated at 0.83% of the total anticancer drug sales value in Korea from 2013-2017. CONCLUSIONS: The prices of anticancer drugs in Korea were similar to the lowest prices among the seven other study countries. A pre-listing and post-evaluation scheme should be considered to improve patient access to novel anticancer drugs by reducing the reimbursement review time and uncertainties.


Subject(s)
Antineoplastic Agents , Drug Costs , France , Germany , Humans , Italy , Japan , Republic of Korea , Switzerland
8.
Phys Chem Chem Phys ; 22(14): 7597-7605, 2020 Apr 14.
Article in English | MEDLINE | ID: mdl-32226986

ABSTRACT

The long stagnation of the photo-conversion efficiency of kesterites below 13% is a source of frustration in the scientific community. In this study, we investigated the effects of sodium on the passivation of grain boundaries and defects in Cu2ZnSnSe4 (CZTSe) grown on a soda-lime glass (SLG) and borosilicate (BS) glass. Because BS glass does not inherently contain sodium, we placed a thin layer of NaF between CZTSe and Mo. The composition of the samples is Cu-poor and Zn-rich. The distribution of sodium and its contributions to phase formation and defects were examined by cross-sectional energy-dispersive X-ray profiling, Raman scattering spectroscopy and imaging, surface potential and photoluminescence. From the experimental results, it can be strongly claimed that sodium ions segregate predominantly near the grain boundaries and reduce CuZn-related defects. These local surface imaging analyses provided the exact locations of the secondary phases. In particular, the photo-assisted scanning probe method enabled us to observe the changes in the optoelectrical properties of the thin films and the carrier behavior within the materials. Further studies with distinct alkali ions and optimal processing conditions will pave a way to improve the performance of kesterite solar cells.

9.
J Ginseng Res ; 44(1): 50-57, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32148389

ABSTRACT

BACKGROUND: The cellular senescence of primary cultured cells is an irreversible process characterized by growth arrest. Restoration of senescence by ginsenosides has not been explored so far. Rg3(S) treatment markedly decreased senescence-associated ß-galactosidase activity and intracellular reactive oxygen species levels in senescent human dermal fibroblasts (HDFs). However, the underlying mechanism of this effect of Rg3(S) on the senescent HDFs remains unknown. METHODS: We performed a label-free quantitative proteomics to identify the altered proteins in Rg3(S)-treated senescent HDFs. Upregulated proteins induced by Rg3(S) were validated by real-time polymerase chain reaction and immunoblot analyses. RESULTS: Finally, 157 human proteins were identified, and variable peroxiredoxin (PRDX) isotypes were highly implicated by network analyses. Among them, the mitochondrial PRDX3 was transcriptionally and translationally increased in response to Rg3(S) treatment in senescent HDFs in a time-dependent manner. CONCLUSION: Our proteomic approach provides insights into the partial reversing effect of Rg3 on senescent HDFs through induction of antioxidant enzymes, particularly PRDX3.

10.
ACS Appl Mater Interfaces ; 12(2): 2490-2496, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31840505

ABSTRACT

Steam generation by eco-friendly solar energy has immense potential in terms of low-cost power generation, desalination, sanitization, and wastewater treatment. Herein, highly efficient steam generation in a bilayer solar steam generator (BSSG) is demonstrated, which is comprised of a large-area SnSe-SnSe2 layer deposited on a glassy carbon foam (CF). Both CF and SnSe-SnSe2 possess high photothermal conversion capabilities and low thermal conductivities. The combined bilayer system cumulatively converts input solar light into heat through phonon-assisted transitions in the indirect band gap SnSe-SnSe2 layer, together with trapping of sunlight via multiple scattering due to the porous morphology of the CF. This synergistic effect leads to efficient broadband solar absorption. Moreover, the low out-of-plane thermal conductivities of SnSe-SnSe2 and CF confine the generated heat at the evaporation surface, resulting in a significant reduction of heat losses. Additionally, the hydrophilic nature of the acid-treated CF offers effective water transport via capillary action, required for efficient solar steam generation in a floating form. A high evaporation rate (1.28 kg m-2 h-1) and efficiency (84.1%) are acquired under 1 sun irradiation. The BSSG system shows high recyclability, stability, and durability under repeated steam-generation cycles, which renders its practical device applications possible.

11.
Small ; 15(38): e1901793, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31379110

ABSTRACT

Band-like transport behavior of H-doped transition metal dichalcogenide (TMD) channels in field effect transistors (FET) is studied by conducting low-temperature electrical measurements, where MoTe2 , WSe2 , and MoS2 are chosen for channels. Doped with H atoms through atomic layer deposition, those channels show strong n-type conduction and their mobility increases without losing on-state current as the measurement temperature decreases. In contrast, the mobility of unintentionally (naturally) doped TMD FETs always drops at low temperatures whether they are p- or n-type. Density functional theory calculations show that H-doped MoTe2 , WSe2 , and MoS2 have Fermi levels above conduction band edge. It is thus concluded that the charge transport behavior in H-doped TMD channels is metallic showing band-like transport rather than thermal hopping. These results indicate that H-doped TMD FETs are practically useful even at low-temperature ranges.

12.
Nanotechnology ; 30(38): 384001, 2019 Sep 20.
Article in English | MEDLINE | ID: mdl-31181554

ABSTRACT

High quality gallium sulfide II (GaS) and gallium sulfide III ([Formula: see text]) thin films on [Formula: see text]/Si substrates were simultaneously grown by using physical vapor deposition with GaS powder as a single precursor. By controlling the substrate temperature, we can selectively grow either GaS or Ga2S3 thin films on SiO2/Si substrates. Relatively high and low substrate temperature conditions resulted in Ga2S3 and GaS thin films, respectively. The synthesized thin films were characterized by x-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and x-ray photoelectron spectroscopy analyses.

13.
Obstet Gynecol Sci ; 61(5): 590-597, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30254995

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the clinicopathological features of minimal deviation adenocarcinoma (MDA) and to analyze its prognostic factors. METHODS: We retrospectively analyzed the medical records of 17 patients who were diagnosed with MDA at a single institution between January 2005 and December 2015. RESULTS: The median age of the patients was 47.7 years (33-75 years). MDA was diagnosed in 7 patients (41.2%) before performing definitive surgery. Stage IB disease was diagnosed in 12 patients (70.6%) and advanced stage disease (stage II: 3, stage III: 2) in 5. MDA was incidentally diagnosed following hysterectomy for benign conditions in 6 patients. Adjuvant therapy was administered to 13 patients (76.5%). During median follow-up over 33.6 months (7-99 months), 11 patients (64.7%) showed no evidence of disease, 6 (35.3%) showed persistent or recurrent disease and 5 died of the disease. Peutz-Jeghers syndrome was not suspected in any patient, and no mutation was detected in the 3 patients who underwent genetic testing. Univariate analysis showed that advanced stage disease (P=0.016) and lymphovascular space invasion (P=0.002) demonstrated a statistically significant association with poor overall survival (OS) rates. Advanced stage disease continued to show a significant association with poor OS rates (hazard ratio, 2.92; 95% confidence interval, 1.097-7.746; P=0.032) even after multivariate analysis. CONCLUSION: Early diagnosis is important to manage MDA. Clinicians should consider MDA among the differential diagnoses in patients with a suspicious clinical presentation even with negative cervical screening tests.

15.
J Gynecol Oncol ; 29(4): e43, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29770616

ABSTRACT

OBJECTIVE: The aim of the present study was to assess the frequency of germline mutations in patients with peritoneal carcinoma (PC) or the fallopian tube carcinoma (FTC), using a multi-gene panel. METHODS: Twenty-six patients diagnosed with either PC or FTC between January 2013 and December 2016 were recruited consecutively. Germline DNA was sequenced using a 6-gene next generation sequencing (NGS) panel following genetic counseling. Surgico-medical information was obtained from hospital records. Genetic variations were detected using the panel and were cross-validated by Sanger direct sequencing. RESULTS: Germline BRCA1/2 mutations were identified in 6 patients (23.1%). Four were detected in patients with PC and 2 were in FTC patients. No mutations were detected in TP53, PTEN, CDH1, or PALB2. We identified 11 variant of uncertain significance (VUS) in 9 patients; 2 in BRCA1, 3 in BRCA2, 2 in TP53, and 4 in CDH1. We also detected a CDH1 c.2164+16->A VUS in 3 patients. CONCLUSION: The prevalence of germline BRCA1/2 mutations in patients with PC or FTC is comparable to that of BRCA1/2 mutations in epithelial ovarian cancer patients.


Subject(s)
Genes, BRCA1 , Genes, BRCA2 , Germ-Line Mutation , Peritoneal Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Cohort Studies , Fallopian Tube Neoplasms/genetics , Female , Humans , Middle Aged , Neoplasm Staging , Sequence Analysis, DNA
16.
Int J Gynecol Cancer ; 28(2): 308-315, 2018 02.
Article in English | MEDLINE | ID: mdl-29240602

ABSTRACT

OBJECTIVE: The aim of the present study was to investigate unclassified variants (UVs) in BRCA1 and 2 of Korean patients with ovarian cancer. METHODS: We retrospectively analyzed 138 patients diagnosed with ovarian/fallopian tubal/peritoneal cancer between January 2013 and January 2016, whose BRCA genetic test results and clinical characteristics were available for review. Patient peripheral blood lymphocyte specimens were assessed for BRCA mutations and variations by direct sequencing. Identified UVs were classified according to several algorithms. RESULTS: The results of genetic testing revealed 31 (22.5%, 31/138) pathogenic BRCA mutations (24 BRCA1, 7 BRCA2 mutations). The BRCA1 c.390C>A mutation was observed in 4 patients (12.9%, 4/31). Thirty-four (24.6%, 34/138) BRCA UVs were identified in 33 patients. Of these, the BRCA1 c.4883T>C and BRCA2 c.8187G>T variants were each detected in 4 patients (4/34, 11.8%). According to the used algorithms and cosegregation test, the BRCA1 c.5339T>C and BRCA2 c.8437_8439delGGA variants were both predicted to be likely pathogenic. CONCLUSIONS: The 2 identified likely pathogenic UVs require further verification with clinical evidence. Clarifying the clinical significance of UVs is an increasingly important step for cancer treatment in the current era of precision medicine.


Subject(s)
BRCA1 Protein/genetics , BRCA2 Protein/genetics , Mutation , Ovarian Neoplasms/genetics , Adult , Aged , Aged, 80 and over , DNA Mutational Analysis , Female , Genetic Predisposition to Disease , Genetic Testing , Humans , Middle Aged , Ovarian Neoplasms/epidemiology , Polymorphism, Single Nucleotide , Republic of Korea/epidemiology , Retrospective Studies , Young Adult
17.
Arthroscopy ; 33(10): 1884-1895, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28655477

ABSTRACT

PURPOSE: To evaluate the surgical treatment of the discoid lateral meniscus (DLM) with long-term follow-up and to search which factors are related to good clinical or radiological outcomes. METHODS: Search was performed using a MEDLINE, EMBASE, and Cochrane database, and each of the selected studies was evaluated for methodological quality using a risk of bias (ROB) covering 7 criteria. Clinical and radiological outcomes with more than 5 years of follow-up were evaluated after surgical treatment of DLM. They were analyzed according to the age, follow-up period, kind of surgery, DLM type, and alignment. RESULTS: Eleven articles (422 DLM cases) were included in the final analysis. Among 7 criteria, 3 criteria showed little ROB in all studies. However, 4 criteria showed some ROB ("Yes" in 63.6% to 81.8%). The minimal follow-up period was 5.5 years (weighted mean follow-up: 9.1 years). Surgical procedures were performed with open or arthroscopic partial central meniscectomy, subtotal meniscectomy, total meniscectomy, or partial meniscectomy with repair. The majority of the studies showed good clinical results. Mild joint space narrowing was reported in the lateral compartment, but none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy could be related to degenerative change. The majority of the complications was osteochondritis dissecans at the lateral femoral condyle (13 cases) and reoperation was performed by osteochondritis dissecans (4 cases), recurrent swelling (2 cases), residual symptom (1 case), stiffness (1 case), and popliteal stenosis (1 case). CONCLUSIONS: Good clinical results were obtained with surgical treatment of symptomatic DLM. The progression of degenerative change was minimal and none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy were possible risk factors for degenerative changes. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.


Subject(s)
Knee Joint/surgery , Menisci, Tibial/abnormalities , Menisci, Tibial/surgery , Age Factors , Humans , Osteochondritis Dissecans/etiology , Osteochondritis Dissecans/surgery , Postoperative Complications , Recurrence , Risk Factors
18.
Obstet Gynecol Sci ; 60(3): 289-295, 2017 May.
Article in English | MEDLINE | ID: mdl-28534015

ABSTRACT

OBJECTIVE: To compare the oncologic and obstetric outcomes in reproductive-age females with borderline ovarian tumors (BOTs) treated with cyst enucleation (CE) or unilateral salpingo-oophorectomy (USO). METHODS: The medical records of patients with BOTs treated between 1998 and 2014 were retrospectively reviewed. The recurrence rates in the USO and CE groups were compared, and the postoperative obstetric outcomes were assessed via telephone survey. RESULTS: Eighty-nine patients with BOTs underwent USO, and 19 underwent CE. Of these, six patients had recurrent BOTs. The recurrence rate was significantly lower in the USO group (3/89, 3.4%) than in the CE group (3/19, 15.8%) (P=0.032). All patients with recurrent disease were successfully treated with further surgery. Of the 76 patients interviewed by telephone, 71 (93.4%) resumed regular menstruation after surgery. Twenty-six of the 32 patients (81.3%) who attempted to conceive had successful pregnancies. USO (19/24, 79.2%), like CE (7/8, 87.5%), resulted in favorable pregnancy rates for patients with BOTs. CONCLUSION: USO is a suitable fertility-preserving surgery for women with BOTs. CE is also an acceptable option for select patients.

19.
Sci Rep ; 6: 39334, 2016 12 23.
Article in English | MEDLINE | ID: mdl-28008951

ABSTRACT

Insulin-like growth factor-binding protein 5 (IGFBP-5) plays a role in cell growth, differentiation, and apoptosis. In this study, we found that IGFBP5 was markedly downregulated in ovarian cancer tissue. We investigated the functional significance of IGFBP-5 as a tumor suppressor. To determine functional regions of IGFBP-5, truncation mutants were prepared and were studied the effect on tumor growth. Expression of C-terminal region of IGFBP-5 significantly decreased tumor growth in an ovarian cancer xenograft. A peptide derived from the C-terminus of IGFBP-5 (BP5-C) was synthesized to evaluate the minimal amino acid motif that retained anti-tumorigenic activity and its effect on angiogenesis was studied. BP5-C peptide decreased the expression of VEGF-A and MMP-9, phosphorylation of Akt and ERK, and NF-kB activity, and inhibited angiogenesis in in vitro and ex vivo systems. Furthermore, BP5-C peptide significantly decreased tumor weight and angiogenesis in both ovarian cancer orthotopic xenograft and patient-derived xenograft mice. These results suggest that the C-terminus of IGFBP-5 exerts anti-cancer activity by inhibiting angiogenesis via regulation of the Akt/ERK and NF-kB-VEGF/MMP-9 signaling pathway, and might be considered as a novel angiogenesis inhibitor for the treatment of ovarian cancer.


Subject(s)
Insulin-Like Growth Factor Binding Protein 5/metabolism , Neovascularization, Pathologic , Ovarian Neoplasms/pathology , Animals , DNA Mutational Analysis , Disease Models, Animal , Female , Heterografts , Humans , Insulin-Like Growth Factor Binding Protein 5/genetics , Mice , Neoplasm Transplantation , Sequence Deletion , Signal Transduction
20.
Int J Gynecol Cancer ; 26(8): 1515-20, 2016 10.
Article in English | MEDLINE | ID: mdl-27465902

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the clinicopathologic features of placental site trophoblastic tumors (PSTTs) in Korea. METHODS/MATERIALS: Twenty patients given a diagnosis of PSTT in Korea (1990-2013) were evaluated retrospectively, including 14 patients identified through a literature review and 6 patients identified through a medical chart review of a single institution. The analysis included patient age, antecedent pregnancies, time since antecedent pregnancy, presenting symptoms, serum ß-human chorionic gonadotropin level, International Federation of Gynecology and Obstetrics stage, treatment, outcome, and follow-up. RESULTS: The mean age of the 20 patients was 32 years (range, 25-53 years). The antecedent pregnancies included 8 term pregnancies, 8 abortions, and 2 molar pregnancies. The time since the antecedent pregnancy was less than 1 year in 16 patients (80%). Nineteen patients (95%) presented with abnormal vaginal spotting or amenorrhea. Serum ß-human chorionic gonadotropin levels ranged from normal to 13,480 mIU/mL, although most patients (80%) had a level less than 1000 mIU/mL. Seventeen patients (85%) presented with stage I disease. Ten patients (50%) underwent hysterectomy, and 14 patients (70%) were treated with chemotherapy with or without hysterectomy. In 11 evaluated patients, the median mitotic count index was 3.4 (0.4-10) per 10 high-power fields. The median follow-up time was 17 months (range, 1-68 months). There was no recurrence or death from disease. CONCLUSIONS: Korean patients with PSTT often have early-stage disease, which has a favorable prognosis even with fertility-preserving therapy. However, international studies are necessary to determine the optimal treatment and prognostic factors.


Subject(s)
Trophoblastic Tumor, Placental Site/pathology , Adult , Female , Humans , Middle Aged , Pregnancy , Republic of Korea , Retrospective Studies
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