Positive cross talk between FOXL2 and antimüllerian hormone regulates ovarian reserve

OBJECTIVE

To demonstrate interregulation between FOXL2 and antimüllerian hormone (AMH) in ovarian folliculogenesis.

DESIGN

Cell culture and animal study.

SETTING

University research laboratory.

ANIMAL(S)

Five-week-old B6C3F1 mice.

INTERVENTIONS(S)

Molecular analysis and in vivo mouse experiment were performed to demonstrate that AMH is a target gene of FOXL2 in the ovary.

MAIN OUTCOME MEASURE(S)

To determine whether FOXL2 transactivates AMH, luciferase reporter assay, electrophoretic mobility shift assay, and chromatin immuniprecipitation were conducted. Using an in vivo nucleic acid delivery system, the expression of AMH and/or FOXL2 was modulated in the mouse, and the ovaries were histologically analyzed.

RESULT(S)

AMH is an endogenous target gene of FOXL2. In contrast, mutated FOXL2s found in premature ovarian failure patients were defective in their ability to activate AMH transcription in human granulosa cells. In vivo mouse gene delivery experiments revealed that Amh-knockdown accelerated follicle growth; however, the acceleration was prevented by ectopic expression of FOXL2.

CONCLUSION(S)

AMH and FOXL2 collaboratively work to reserve ovarian follicles.

A multiepitope of XBP1, CD138 and CS1 peptides induces myeloma-specific cytotoxic T lymphocytes in T cells of smoldering myeloma patients

We evaluated a cocktail of HLA-A2-specific peptides including heteroclitic XBP1 US184-192 (YISPWILAV), heteroclitic XBP1 SP367-375 (YLFPQLISV), native CD138260-268 (GLVGLIFAV) and native CS1239-247 (SLFVLGLFL), for their ability to elicit multipeptide-specific cytotoxic T lymphocytes (MP-CTLs) using T cells from smoldering multiple myeloma (SMM) patients. Our results demonstrate that MP-CTLs generated from SMM patients' T cells show effective anti-MM responses including CD137 (4-1BB) upregulation, CTL proliferation, interferon-γ production and degranulation (CD107a) in an HLA-A2-restricted and peptide-specific manner. Phenotypically, we observed increased total CD3(+)CD8(+) T cells (>80%) and cellular activation (CD69(+)) within the memory SMM MP-CTL (CD45RO(+)/CD3(+)CD8(+)) subset after repeated multipeptide stimulation. Importantly, SMM patients could be categorized into distinct groups by their level of MP-CTL expansion and antitumor activity. In high responders, the effector memory (CCR7(-)CD45RO(+)/CD3(+)CD8(+)) T-cell subset was enriched, whereas the remaining responders' CTL contained a higher frequency of the terminal effector (CCR7(-)CD45RO(-)/CD3(+)CD8(+)) subset. These results suggest that this multipeptide cocktail has the potential to induce effective and durable memory MP-CTL in SMM patients. Therefore, our findings provide the rationale for clinical evaluation of a therapeutic vaccine to prevent or delay progression of SMM to active disease.

Andrographolide inhibits HMGB1-induced inflammatory responses in human umbilical vein endothelial cells and in murine polymicrobial sepsis

AIM

Nuclear DNA-binding protein high-mobility group box 1 (HMGB1) protein acts as a late mediator of severe vascular inflammatory conditions, such as septic shock, upregulating pro-inflammatory cytokines. Andrographolide (AG) is isolated from the plant of Andrographis paniculata and used as a folk medicine for treatment of viral infection, diarrhoea, dysentery and fever. However, the effect of AG on HMGB1-induced inflammatory response has not been studied.

METHODS

Firstly, we accessed this question by monitoring the effects of post-treatment AG on lipopolysaccharide (LPS) and caecal ligation and puncture (CLP)-mediated release of HMGB1 and HMGB1-mediated regulation of pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and septic mice.

RESULTS

Post-treatment AG was found to suppress LPS-mediated release of HMGB1 and HMGB1-mediated cytoskeletal rearrangements. AG also inhibited HMGB1-mediated hyperpermeability and leucocyte migration in septic mice. In addition, AG inhibited production of tumour necrosis factor-α (TNF-α) and activation of AKT, nuclear factor-κB (NF-κB) and extracellular-regulated kinases (ERK) 1/2 by HMGB1 in HUVECs. AG also induced downregulation of CLP-induced release of HMGB1, production of interleukin (IL) 1β/6/8 and mortality.

CONCLUSION

Collectively, these results suggest that AG may be regarded as a candidate therapeutic agent for the treatment of vascular inflammatory diseases via inhibition of the HMGB1 signalling pathway.

Fluorescence imaging of nanoscale domains in polymer blends using stochastic optical reconstruction microscopy (STORM)

High-resolution fluorescence techniques that provide spatial resolution below the diffraction limit are attractive new methods for structural characterization of nanostructured materials. For the first time, we apply the super-resolution technique of Stochastic Optical Reconstruction Microscopy (STORM), to characterize nanoscale structures within polymer blend films. The STORM technique involves temporally separating the fluorescence signals from individual labeled polymers, allowing their positions to be localized with high accuracy, yielding a high-resolution composite image of the material. Here, we describe the application of the technique to demixed blend films of polystyrene (PS) and poly(methyl methacrylate) (PMMA), and find that STORM provides comparable structural characteristics as those determined by Atomic Force Microscopy (AFM) and scanning electron microscopy (SEM), but with all of the advantages of a far-field optical technique.

Antibiotic stress-induced modulation of the endoribonucleolytic activity of RNase III and RNase G confers resistance to aminoglycoside antibiotics in Escherichia coli

Here, we report a resistance mechanism that is induced through the modulation of 16S ribosomal RNA (rRNA) processing on the exposure of Escherichia coli cells to aminoglycoside antibiotics. We observed decreased expression levels of RNase G associated with increased RNase III activity on rng mRNA in a subgroup of E. coli isolates that transiently acquired resistance to low levels of kanamycin or streptomycin. Analyses of 16S rRNA from the aminoglycoside-resistant E. coli cells, in addition to mutagenesis studies, demonstrated that the accumulation of 16S rRNA precursors containing 3–8 extra nucleotides at the 5’ terminus, which results from incomplete processing by RNase G, is responsible for the observed aminoglycoside resistance. Chemical protection, mass spectrometry analysis and cell-free translation assays revealed that the ribosomes from rng-deleted E. coli have decreased binding capacity for, and diminished sensitivity to, streptomycin and neomycin, compared with wild-type cells. It was observed that the deletion of rng had similar effects in Salmonella enterica serovar Typhimurium strain SL1344. Our findings suggest that modulation of the endoribonucleolytic activity of RNase III and RNase G constitutes a previously uncharacterized regulatory pathway for adaptive resistance in E. coli and related gram-negative bacteria to aminoglycoside antibiotics.

MCL-1ES induces MCL-1L-dependent BAX- and BAK-independent mitochondrial apoptosis

MCL-1 (myeloid cell leukemia-1), a member of the BCL-2 family, has three splicing variants, antiapoptotic MCL-1L, proapoptotic MCL-1S, and MCL-1ES. We previously reported cloning MCL-1ES and characterizing it as an apoptotic molecule. Here, we investigated the molecular mechanism by which MCL-1ES promotes cell death. MCL-1ES was distinct from other proapoptotic BCL-2 members that induce apoptosis by promoting BAX or BAK oligomerization, leading to mitochondrial outer membrane permeabilization (MOMP), in that MCL-1ES promoted mitochondrial apoptosis independently of both BAX and BAK. Instead, MCL-1L was crucial for the apoptotic activity of MCL-1ES by facilitating its proper localization to the mitochondria. MCL-1ES did not interact with any BCL-2 family proteins except for MCL-1L, and antiapoptotic BCL-2 members failed to inhibit apoptosis induced by MCL-1ES. The BCL-2 homology 3 (BH3) domain of MCL-1ES was critical for both MCL-1ES association with MCL-1L and apoptotic activity. MCL-1ES formed mitochondrial oligomers, and this process was followed by MOMP and cytochrome c release in a MCL-1L-dependent manner. These findings indicate that MCL-1ES, as a distinct proapoptotic BCL-2 family protein, may be useful for intervening in diseases that involve uncontrolled MCL-1L.

Differential apoptotic and proliferative activities of wild-type FOXL2 and blepharophimosis-ptosis-epicanthus inversus syndrome (BPES)-associated mutant FOXL2 proteins

FOXL2 is an essential transcription factor that is required for proper development of the ovary and eyelid. Mutations in FOXL2 cause an autosomal dominant genetic disorder, blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). BPES type I patients have eyelid malformation and premature ovarian failure leading to infertility, whereas women with type II BPES are fertile or subfertile. In the present study, we evaluated and compared apoptotic and antiproliferative activities of wild-type (WT) and mutant FOXL2 proteins found in BPES type I and II in human granulosa cell tumor-derived KGN cells. Ectopic expression of WT FOXL2 induced apoptosis and inhibited cell cycle progression in human granulosa cells. In contrast, mutated FOXL2s found in BPES type I significantly reduced these activities, whereas mutated FOXL2s in BPES type II showed intermediate activities. Furthermore, mutant FOX L2 proteins were defective in activating transcription of target genes including Caspase 8, TNF-R1, FAS, p21, and BMP4, which regulate apoptosis, proliferation, and differentiation of granulosa cells. Thus, decreased apoptotic and antiproliferative activities caused by mutant forms of FOXL2 found in BPES patients may at least partially contribute to the pathophysiology of ovarian dysfunction.

Inhibition of Xenograft tumor growth by gold nanoparticle-DNA oligonucleotide conjugates-assisted delivery of BAX mRNA

Use of non-biological agents for mRNA delivery into living systems in order to induce heterologous expression of functional proteins may provide more advantages than the use of DNA and/or biological vectors for delivery. However, the low efficiency of mRNA delivery into live animals, using non-biological systems, has hampered the use of mRNA as a therapeutic molecule. Here, we show that gold nanoparticle-DNA oligonucleotide (AuNP-DNA) conjugates can serve as universal vehicles for more efficient delivery of mRNA into human cells, as well as into xenograft tumors generated in mice. Injections of BAX mRNA loaded on AuNP-DNA conjugates into xenograft tumors resulted in highly efficient mRNA delivery. The delivered mRNA directed the efficient production of biologically functional BAX protein, a pro-apoptotic factor, consequently inhibiting tumor growth. These results demonstrate that mRNA delivery by AuNP-DNA conjugates can serve as a new platform for the development of safe and efficient gene therapy.

Note: Near-field imaging of thermal radiation at low temperatures by passive millimeter-wave microscopy

Imaging of thermal radiation with a spatial resolution below the diffraction limit is demonstrated with a passive millimeter-wave microscope. This technique utilizes a sensitive radiometric receiver in combination with a scanning near-field microscope. Experiments were performed at 50 GHz (λ = 6 mm) with sample temperatures ranging from room temperature down to 160 K, and the performance was shown to be superior to that achieved with passive imaging systems in the infrared region. The images are affected by non-uniformities in the transmission of thermal radiation from the sample to the receiver via the near-field probe and the reflection of thermal radiation back to the receiver from the probe. The effects of these non-uniformities were successfully removed using a sample image acquired by active measurements using a vector network analyzer.

Two-stage anaerobic fluidized-bed membrane bioreactor treatment of settled domestic wastewater

A two-stage anaerobic fluidized-bed membrane bioreactor (SAF-MBR) system was applied for the treatment of primary-settled domestic wastewater that was further pre-treated by either 10 μm filtration or 1 mm screening. While the different pre-treatment options resulted in different influent qualities, the effluent qualities were quite similar. In both cases at a total hydraulic retention time of 2.3 h and 25 °C, chemical oxygen demand and biochemical oxygen demand (BOD5) removals were 84-91% and 92-94%, with effluent concentrations lower than 25 and 7 mg/L, respectively. With a membrane flux of 6-12 L/m(2)/h, trans-membrane pressure remained below 0.2 bar during 310 d of continuous operation without need for membrane chemical cleaning or backwashing. Biosolids production was estimated to be 0.028-0.049 g volatile suspended solids/g BOD5, which is far less than that with comparable aerobic processes. Electrical energy production from combined heat and power utilization of the total methane produced (gaseous and dissolved) was estimated to be more than sufficient for total system operation.

DUSP6 is a novel transcriptional target of p53 and regulates p53-mediated apoptosis by modulating expression levels of Bcl-2 family proteins

p53 regulates various cellular responses through transcriptional regulation of distinct sets of target genes. Dual specificity phosphatase 6 (DUSP6) is a cytosolic phosphatase that inactivates the extracellular-signal-regulated kinase 1/2 (ERK1/2). This study demonstrates that p53 transactivates DUSP6 in human colorectal HCT116 cells to regulate ERK1/2 in p53-mediated cell death. DUSP6 is transactivated by p53 overexpression and genotoxic agents, and chromatin immunoprecipitation revealed two p53-binding sites in the DUSP6 promoter responsible for DUSP6 induction. Expression of shDUSP6 inhibited 5'-FU-induced cell death, whereas overexpression of DUSP6 increased susceptibility to 5'-FU. 5'-FU treatment dephosphorylated ERK in a DUSP6-dependent manner, resulting in destabilization of Bcl-2 and stabilization of Bad. These results provide insights on the modulatory role of p53 in the survival pathway by up-regulating DUSP6.

Disturbed relaxin signaling pathway and testicular dysfunction in mouse offspring upon maternal exposure to simazine

Simazine is a triazine herbicide that is being widely applied worldwide and commonly detected in surface and groundwater. Despite its popular use in controlling weeds and algae, very limited information is available regarding its toxicity. In the present study, pregnant mice were orally exposed to low doses (0, 5, 50, or 500 µg/kg body weight per day) of simazine during gestation and lactation, during which no overt maternal toxic response was detected, and their offspring was assessed. Simazine-exposed male offspring showed decreased body, testicular, and epididymis weight, increased testicular apoptosis, and decreased sperm concentrations. Differentially-expressed genes in the testes of male offspring exposed to simazine were identified by DNA microarray, revealing 775 upregulated and 791 downregulated genes; among these, the relaxin-family peptide receptor 1 (Rxfp1), which is the receptor for relaxin hormone, was significantly downregulated. In addition, the expression of target genes in the relaxin pathway, including nitric oxide synthase 2 (Nos2) and Nos3, was significantly decreased in simazine-exposed F1 testes. Moreover, simazine inhibited NO release, and knockdown of Rxfp1 blocked the inhibitory action of simazine on NO production in testicular Leydig cells. Therefore, the present study provides a better understanding of the toxicities associated with the widely used herbicide simazine at environmentally relevant doses by demonstrating that maternal exposure interferes with the pleotropic relaxin-NO signaling pathway, impairing normal development and reproductive activity of male offspring.

Effective delivery of anti-miRNA DNA oligonucleotides by functionalized gold nanoparticles

MicroRNAs (miRNAs) are gaining recognition as essential regulators involved in many biological processes, and they are emerging as therapeutic targets for treating disease. Here, we introduce a method for effective delivery of anti-miRNA oligonucleotides (AMOs) using functionalized gold nanoparticles (AuNPs). To demonstrate the ability of AMOs to silence miRNA, we selected miR-29b, which is known to downregulate myeloid cell leukemia-1 (MCL-1), a factor responsible for promoting cell survival. We first generated AuNPs coated with cargo DNA, which was then coupled to complementary DNA linked to an antisense miR-29b sequence. When the AuNPs were delivered into HeLa cells, MCL-1 protein and mRNA levels were increased significantly. Furthermore, apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) was inhibited, proving that AMOs targeting miR-29b were effectively delivered by our innovative AuNP. In addition, we provided evidence that AuNP could deliver other AMOs against miR-21 into two independent cell lines, KGN and 293T, suggesting that the AuNP conjugates can be versatile for any AMO and cell type.

Modulation of biological processes in the nucleus by delivery of DNA oligonucleotides conjugated with gold nanoparticles

The development of a method that can efficiently deliver nucleic acids into the nucleus of living systems remains one of the key challenges for experimental and therapeutic use of nonbiological gene delivery agents. In the current study, we demonstrate a functionalized gold nanoparticle (AuNP) that can serve as a universal carrier for the delivery of DNA oligonucleotides (oligos) into the nucleus. We designed various types of DNA oligos to redirect alternative splicing of pre-mRNAs, such as MCL-1 and BCL-6, and to sequester transcriptional factors, including estrogen receptor α and p53. We successfully delivered the oligos into the nucleus, resulting in the targeted effects. In addition, injection of the antisense DNAs into a xenograft tumor in a mouse model system resulted in inhibited development of the tumor by redirecting the alternative splicing of the pre-mRNA. Our findings show that these nanoconjugates efficiently load and deliver antisense DNAs to redirect gene splicing or double-stranded DNAs to decoy gene transcription by transcriptional factors into mammalian cells and in vivo animals. Therefore, our lego-like AuNP gene delivery system can be used universally to control different biological processes by modulating nuclear gene expression events in living systems.

The apolipoprotein A-I level is downregulated in the granulosa cells of patients with polycystic ovary syndrome and affects steroidogenesis

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder found in women. The etiology of PCOS is still not clear, and there are no available studies on the proteome analysis of granulosa cells (GCs) in PCOS patients. To identify the pathogenic mechanisms and potential diagnostic markers for PCOS, we conducted proteomic profiling of GCs in PCOS patients by two-dimensional gel electrophoresis and liquid chromatography coupled with mass spectrometry (LC-MS/MS) analyses. The proteomic analysis yielded eight downregulated and 12 upregulated proteins in PCOS patients, among which apolipoprotein A-I (ApoA-I) showed significant downregulation in PCOS patients as confirmed by Western blotting. Knockdown of ApoA-I decreased the number of transcripts of steroidogenic enzymes in a granulosa cell line (KGN), while its overexpression generally increased the level of expression of these enzymes. Furthermore, modulation of the expression level of ApoA-I in the granulosa cells altered progesterone production. Therefore, this study suggests that ApoA-I can be useful as a granulosa cell biomarker of PCOS patients and that downregulated ApoA-I may be related to the disturbed production of steroid hormones in PCOS patients.

Absence of a FOXL2 mutation (402C→G) in the blood of adult-type granulosa cell tumor patients possessing the FOXL2 mutation

Recently, a new mutation in FOXL2, c.402C→G leading to a p.C134W change, was reported to be found in 97% of adult-type ovarian granulosa cell tumors (GCTs) tested. In the current study, we compared the FOXL2 sequences of genomic DNA isolated from both GCT and blood. Although the GCTs of patients possessed the FOXL2 mutation, their FOXL2 nucleotide sequences of genomic DNA isolated from matching blood samples lacked the 402C→G mutation. Therefore, we confirmed that the nucleotide alteration of FOXL2 is due to a somatic mutation and demonstrated that sequencing of blood DNA for the detection of the FOXL2 mutation is not a useful method for the diagnosis of GCT.

Association of endothelial nitric oxide synthase polymorphisms with coronary artery disease in Korean individuals with or without diabetes mellitus

Polymorphisms of the endothelial nitric oxide synthase (eNOS) gene have been implicated in various diseases, but their roles as risk factors in type 2 diabetes mellitus (T2DM) with regard to coronary artery disease (CAD) are largely unknown. Therefore, we investigated the association of the genotypes and haplotypes of eNOS polymorphisms in CAD with T2DM. A case-control study was performed to evaluate the genotypes and haplotypes of the eNOS polymorphisms (-786T>C, 4a4b and 894G>T) in 192 CAD patients and 196 controls. The same population was also re-organized upon the status of T2DM. The genotypes of eNOS -786T>C, 4a4b and 894G>T polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism. We found that eNOS -786TC+CC and 4a4b+4a4a genotypes were significantly prevalent in the diabetic controls and the diabetic CAD patients compared to the non-diabetic controls or non-diabetic CAD patients, respectively. The frequency of the -786C-4a-894G haplotype was significantly greater in the diabetic CAD patients (p=0.001) and diabetic controls (p=0.023) compared to the non-diabetic controls, whereas the haplotype of -786T-4b-894G was less prevalent in the diabetic CAD patients compared to the non-diabetic controls (p=0.018). Significant associations of the genotypes and the haplotypes were consistently observed in the T2DM group compared to non-DM group, regardless of CAD status. Our finding suggests that the eNOS -786T>C and 4a4b polymorphisms and the -786C-4a-894G haplotype are risk factors for T2DM, whereas the haplotype of -786T-4b-894G has a protective effect against the development of T2DM.

Delivery of shRNA using gold nanoparticle-DNA oligonucleotide conjugates as a universal carrier

The efficient delivery of nucleic acids into mammalian cells is a central aspect of research involving cell biology and medical applications, including the clinical treatment of genetic disorders. We report an efficient small hairpin RNA (shRNA) delivery system that utilizes a single species of gold nanoparticle-DNA oligonucleotide conjugate (AuNP-DNA oligo) as a universal carrier. In vitro synthesized shRNA that is specific to the p53 gene was efficiently delivered into HEK293 and HeLa human cell lines using an AuNP-DNA oligo. The delivery resulted in an 80-90% knockdown of p53 expression. The same AuNP-DNA oligo was also efficient for the delivery of another shRNA, which is specific to the Mcl-1 gene, as well as the repression of MCL-1 expression. The knockdown efficiency of shRNA that was delivered using an AuNP-DNA oligo was comparable with that of a liposome-based shRNA delivery method. Our results offer an alternate delivery system for shRNA that can be used on any gene of interest.

A functionalized gold nanoparticles-assisted universal carrier for antisense DNA

In this study, single-stranded DNA functionalized gold nanoparticles (AuNP GDS) were proved to be efficient gene delivery systems for oligo antisense DNAs specific to any gene of interest without affecting normal cell physiology.

Positional effects of polymorphisms in probe-target sequences on genoplot images of oligonucleotide microarrays

Single nucleotide polymorphisms (SNPs) present in probe-target sequences (SPTS) have been shown to be associated with abnormal genoplot images. We explored the effects of SPTS positions on genoplot images using a data set from a genome-wide association study typed on an Illumina Human Hap300 platform. We screened the physical genomic positions of 308,330 autosomal probes to identify SPTS candidates deposited in dbSNP. The genoplot images across 293 individuals were inspected further in SNPs bearing an SPTS candidate. We identified 35,185 SNPs bearing a single SPTS candidate, including 264 SNPs showing abnormal genoplot images. The frequencies of SPTS at distances within 10 bases from the target SNP were significantly higher in the 264 SNPs showing abnormal genoplot images, than in the remaining 34,921 SNPs (49.62 vs 12.87%; Fisher exact test; P = 2.2 x 10(-16)). Of these 264 SNPs, we randomly selected 20 SNPs and resequenced them in 97 individuals. An SPTS within 10 bases of the target SNP was confirmed in all 20 SNPs, except for one SNP with a small deletion (7 bases) in the probe-target sequence. Taken together, these results suggest an association of a proximal SPTS with an abnormal genoplot image, which could result in spurious genotype detections, highlighting the importance of minimizing systematic errors in microarray experiments.

FOXL2 interacts with steroidogenic factor-1 (SF-1) and represses SF-1-induced CYP17 transcription in granulosa cells

Mutations in FOXL2 are responsible for blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) type I, in which affected women exhibit premature ovarian failure. FOXL2-null mice showed defects in granulosa cell development during folliculogenesis. We screened a rat ovarian yeast two-hybrid cDNA library to identify FOXL2-interacting proteins and found steroidogenic factor-1 (SF-1). Here, we show that human FOXL2 and SF-1 proteins interact in human granulosa cells and that FOXL2 negatively regulates the transcriptional activation of a steroidogenic enzyme, CYP17, by SF-1. Furthermore, FOXL2 mutants found in blepharophimosis-ptosis-epicanthus inversus syndrome type I patients lost the ability to repress CYP17 induction mediated by SF-1. Chromatin immunoprecipitation and EMSA results further revealed that FOXL2 inhibited the binding of SF-1 to the CYP17 promoter, whereas the FOXL2 mutants failed to block this interaction. Therefore, this study identifies a novel regulatory role for FOXL2 on a key steroidogenic enzyme and provides a possible mechanism by which mutations in FOXL2 disrupt normal ovarian follicle development.

Impact of Primary Site Surgical Resection on Survival in Stage IV Breast Cancer

Background: Currently, primary treatments for stage IV breast cancer are radiation and systemic therapy which include chemotherapy, endocrine therapy and targeted therapy. Surgical resection of primary tumor is usually done for tumor-related complications. A recent review suggested that surgery may improve long-term survival in stageIV breast cancer patients. We evaluated the impact of primary site surgical resection on survival in such patients.Material and Methods: We reviewed the records of stage IV breast cancer patients treated at Seoul National University Hospital between 1992 and 2008. Clinical and tumor characteristics, systemic and local treatments were compared for the surgically versus nonsurgically treated patients.Results: Of 199 patients identified, 111(55.8%) recevied surgical excision of their primary tumor and 88(44.2%) did not. The mean survival of surgically treated patients was 67 months versus 52 months for patients those who did not(p=0.0276). In multivariate analysis, after adjustment for ER status, visceral metastasis, number of metastatic sites and herceptin treatment, surgery remained an independent factor associated with improved survival(HR 0.547[95%CI 0.359-0.971] p=0.001).Discussion: Surgical resection of the primary tumor in stage IV breast cancer patient was independently associated with improved survival, even after adjustment for other factors associated with survival. Randomized prospective trials are needed to validate these findings.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3117.

Lympho-Vascular Invasion by Detecting D2-40 Was the Potent Prognostic Predictor in Breast Cancer Patients

(Introduction) Distant metastasis and recurrence are the major factors of prognosis in breast cancer patients. Both of lymphovascular invasion (LVI) and blood vascular invasion (BVI) are known to be the important route for metastasis to regional lymph nodes and systemic metastasis. Despite the importance of vascular invasion as a prognostic factor, the application of vascular invasion as a histopathologic criterion is controversial. The aims of this study were to distinguish between LVI and BVI for the role of prognosis and recurrence in breast cancer patients by using an endothelial subtype specific immunohitochemical stain (podoplanin, D2-40 and CD31)Methods) Sections from 80 paraffin-embedded archival specimens of invasive breast cancer were stained for expression of podoplanin, D2-40, and CD31. The results of immunohistochemical staining were correlated with clinicopathologic features, such as tumor size, the status of lymph node metastases, estrogen receptor status, progesterone receptor status and HER2 expression, and recurrence. The patients with ductal carcinoma in situ and stage 4 breast cancer were excluded.Results) A significant correlation was found in the higher expression of D2-40, and lymph node metastasis. (P=0.02) We found a significant correlation between the expression of D2-40 and the recurrence of breast cancer. (P=0.04) However, there was no significant correlation between BVI and recurrence. A poorer disease free survival was shown in the higher expression of D2-40. (P<0.01) In multivariate analysis, the higher expression of D2-40 revealed a significant association with decreased disease-free survival.Conclusion) The higher expression of D2-40 was the more prognostic predictor than blood vascular invasion in breast cancer patients.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6171.

Escherichia coli ribonuclease III activity is downregulated by osmotic stress: consequences for the degradation of bdm mRNA in biofilm formation

During the course of experiments aimed at identifying genes with ribonuclease III (RNase III)-dependent expression in Escherichia coli, we found that steady state levels of bdm mRNA were dependent on cellular concentrations of RNase III. The half-lives of adventitiously overexpressed bdm mRNA and the activities of a transcriptional bdm'-'cat fusion were observed to be dependent on cellular concentrations of RNase III, indicating the existence of cis-acting elements in bdm mRNA responsive to RNase III. In vitro and in vivo cleavage analyses of bdm mRNA identified two RNase III cleavage motifs, one in the 5'-untranslated region and the other in the coding region of bdm mRNA, and indicated that RNase III cleavages in the coding region constitute a rate-determining step for bdm mRNA degradation. We also discovered that downregulation of the ribonucleolytic activity of RNase III is required for the sustained elevation of RcsB-induced bdm mRNA levels during osmotic stress and that cells overexpressing bdm form biofilms more efficiently. These findings indicate that the Rcs signalling system has an additional regulatory pathway that functions to modulate bdm expression and consequently, adapt E. coli cells to osmotic stress.

Sumoylation of forkhead L2 by Ubc9 is required for its activity as a transcriptional repressor of the Steroidogenic Acute Regulatory gene

Forkhead L2 (FOXL2) is a member of the forkhead/hepatocyte nuclear factor 3 (FKH/HNF3) gene family of transcription factors and acts as a transcriptional repressor of the Steroidogenic Acute Regulatory (StAR) gene, a marker of granulosa cell differentiation. FOXL2 may play a role in ovarian follicle maturation and prevent premature follicle depletion leading to premature ovarian failure. In this study, we found that FOXL2 interacts with Ubc9, an E2-conjugating enzyme that mediates sumoylation, a key mechanism in transcriptional regulation. FOXL2 and Ubc9 are co-expressed in granulosa cells of small and medium ovarian follicles. FOXL2 is sumoylated by Ubc9, and this Ubc9-mediated sumoylation is essential to the transcriptional activity of FOXL2 on the StAR promoter. As FOXL2 is endogenous to granulosa cells, we generated a stable cell line expressing FOXL2 and found that activity of the StAR promoter in this cell line is greatly decreased in the presence of Ubc9. The sumoylation site was identified at lysine 25 of FOXL2. Mutation of lysine 25 to arginine leads to loss of transcriptional repressor activity of FOXL2. Taken together, we propose that Ubc9-mediated sumoylation at lysine 25 of FOXL2 is required for transcriptional repression of the StAR gene and may be responsible for controlling the development of ovarian follicles.