Effects of calcitriol upon TGF-βs and their receptors in trophoblast cells

Calcitriol levels increase during pregnancy, contributing to the hormonal and immunological balance, but its deficiency has been associated with problems during this period. Meanwhile, transforming growth factors-β (TGF-βs) play an important role in the maintenance of fetal-maternal immune tolerance; however, exacerbated concentrations of this growth factor are associated with complicated pregnancies. Therefore, we studied the effects of calcitriol on TGF-βs and their receptors in trophoblast cells. Term placentas from uncomplicated pregnancies after cesarean sections were used for cell cultures. Basal gene expression and the effect of calcitriol upon TGF-β1, TGF-β2, TGF-β3, and their receptors TGF-βR1 and TGF-βR2 were assessed using real-time PCR from trophoblast cells. The presence of TGF-β1, 2, 3, and TGF-βR1 were evaluated by immunofluorescence, and the protein abundance and secretion of TGF-β1 were assessed by Western blot and ELISA, respectively. Basal gene expression of TGF-β1 in trophoblast from term placentas was higher than TGF-β2 and TGF-β3, while TGF-βR2 was higher than TGF-βR1. The presence and cellular localization of TGF-β1, 2, 3, and TGF-βR1 were detected in the cytoplasm of syncytiotrophoblast, with TGF-β1 showing the highest intensity. Calcitriol significantly inhibited gene expression of TGF-β1, TGF-β2, and TGF-βR1. Likewise, calcitriol decreased the secretion and abundance of TGF-β1. In conclusion, results indicate that calcitriol is a regulator of TGF-βs in cultured trophoblast cells from term placentas and therefore may be an important player in the development of healthy pregnancies.

Transcriptional landscape of human trophoblast cells treated with calcitriol and TGF-β1

Calcitriol and transforming growth factor beta 1 (TGF-β1) are unrelated molecules that regulate biological processes according to the genetic target, cell type, and context. Several studies have shown independent effects of calcitriol and TGF-βs on the placenta, but there is no information regarding the impact of their combination on these cells. Therefore, this study analyzed the effects of calcitriol, TGF-β1, and their combination in primary cultures of human trophoblast cells using a whole genome expression microarray. Data analysis revealed a set of differentially expressed genes induced by each treatment. Enrichment pathway analysis identified modulatory effects of calcitriol on genes related to metabolic processes such as vitamin D, steroid, and fat-soluble vitamins as well as antimicrobial and immune responses. In relation to TGF-β1, the analysis showed a few differentially expressed genes that were mainly associated with the neutrophil immune response. Lastly, the analysis revealed that the combination of calcitriol and TGF-β1 up-regulated genes involving both immunologic processes and the biosynthesis of unsaturated fatty acids, eicosanoids, and lipoxins, among others. In contrast, pathways down-regulated by the combination were mostly associated with the catabolic process of acylglycerols and peptides, PPAR signaling pathway, cellular response to low-density lipoprotein stimulus, renin angiotensin system and digestion, mobilization and transport of lipids. Consistent with these results, the combined treatment on human trophoblast cells induced the accumulation of intracellular neutral lipid droplets and stimulated both gene and protein expression of 15-hydroxyprostaglandin dehydrogenase. In conclusion, the results revealed that differentially expressed genes induced by the combination modified the transcriptional landscape compared to each treatment alone, mainly altering the storage, activity and metabolism of lipids, which might have an impact on placental development.

Gene Expression Changes in the Ovary Mediate Non-Anovulatory Mechanisms of Contraception with Levonorgestrel

BACKGROUND

Emergency contraception with levonorgestrel (LNG) is a viable option to prevent unintended pregnancies. Although the efficacy of LNG as an anovulatory agent decreases as treatment approaches ovulation, it still provides some contraceptive benefits.

AIM

To better understand the contraceptive mechanisms of LNG in ovulatory subjects.

METHODS

We conducted a study on Wistar rats that received a single dose of LNG (0.01 or 0.05 mg/kg) on the morning of proestrus before ovulation and evaluated its effects on ovarian gene expression, ovulation, and implantation.

RESULTS

Our findings showed changes in the expression of genes involved in follicular development and oocyte quality. Pregnancy rates - as an indicator of ovulation - and embryo implantation were significantly lower than those in the control group.

CONCLUSIONS

This study suggests that LNG alters regulatory factors in the ovary that are essential for the development of competent fertilizable oocytes, highlighting the non-anovulatory mechanisms by which levonorgestrel may regulate fertility and suggesting that it could be a novel observation that contributes to the understanding of emergency contraception in humans.

Analytical reference framework to analyze non-COVID-19 events

BACKGROUND

The COVID-19 pandemic has disrupted the healthcare system, leading to delays in detection of other non-COVID-19 diseases. This paper presents ANE Framework (Analytics for Non-COVID-19 Events), a reliable and user-friendly analytical forecasting framework designed to predict the number of patients with non-COVID-19 diseases. Prior to 2020, there were analytical models focused on specific illnesses and contexts. Then, most models have focused on understanding COVID-19 behavior. There is a lack of analytical frameworks that enable disease forecasting for non-COVID-19 diseases.

METHODS

The ANE Framework utilizes time series analysis to generate forecasting models. The framework leverages daily data from official government sources and employs SARIMA models to forecast the number of non-COVID-19 cases, such as tuberculosis and suicide attempts.

RESULTS

The framework was tested on five different non-COVID-19 events. The framework performs well across all events, including tuberculosis and suicide attempts, with a Mean Absolute Percentage Error (MAPE) of up to 20% and the consistency remains independent of the behavior of each event. Moreover, a pairwise comparison of averages can lead to over or underestimation of the impact. The disruption caused by the pandemic resulted in a 17% gap (2383 cases) between expected and reported tuberculosis cases, and a 19% gap (2464 cases) for suicide attempts. These gaps varied between 20 and 64% across different cities and regions. The ANE Framework has proven to be reliable for analyzing several diseases and exhibits the flexibility to incorporate new data from various sources. Regular updates and the inclusion of new associated data enhance the framework's effectiveness.

CONCLUSIONS

Current pandemic shows the necessity of developing flexible models to be adapted to different illness data. The framework developed proved to be reliable for the different diseases analyzed, presenting enough flexibility to update with new data or even include new data from different databases. To keep updated on the result of the project allows the inclusion of new data associated with it. Similarly, the proposed strategy in the ANE framework allows for improving the quality of the obtained results with news events.

Dynamic curvature sensing using time expanded ΦOTDR

Shape sensing can be accomplished using optical fiber sensors through different interrogation principles such as fiber Bragg gratings, optical frequency-domain reflectometry (OFDR), or optical time-domain reflectometry (OTDR). These techniques are either not entirely distributed, have poor performance in dynamic sensing, or are only valid for few-meter-long fibers. Here, we present a system able to perform distributed curvature sensing with a range of 125 m, 10-cm resolution, and a sampling rate of 50 Hz. This is done by interrogating three cores of a multi-core fiber (MCF) with the novel, to the best of our knowledge, time-expanded phase-sensitive (TE-Φ)OTDR technique. This system fills a performance gap in fiber shape sensors, opening the door to applications in civil engineering, medicine, or seismology.

Optical fiber point sensors based on forward Brillouin scattering

Forward Brillouin scattering interactions support the sensing and analysis of media outside the cladding boundaries of standard fibers, where light cannot reach. Quantitative point-sensing based on this principle has yet to be reported. In this work, we report a forward Brillouin scattering point-sensor in a commercially available, off-the-shelf multi-core fiber. Pump light at the inner, on-axis core of the fiber is used to stimulate a guided acoustic mode of the entire fiber cross-section. The acoustic wave, in turn, induces photoelastic perturbations to the reflectivity of a Bragg grating inscribed in an outer, off-axis core of the same fiber. The measurements successfully analyze refractive index perturbations on the tenth decimal point and distinguish between ethanol and water outside the centimeter-long grating. The measured forward Brillouin scattering linewidths agree with predictions. The acquired spectra are unaffected by forward Brillouin scattering outside the grating region. The results add point-analysis to the portfolio of forward Brillouin scattering optical fiber sensors.

Security Best Practices: A Critical Analysis Using IoT as a Case Study

Academic research has highlighted the failure of many Internet of Things (IoT) product manufacturers to follow accepted practices, while IoT security best practices have recently attracted considerable attention worldwide from industry and governments. Given current examples of security advice, confusion is evident from guidelines that conflate desired outcomes with security practices to achieve those outcomes. We explore a surprising lack of clarity, and void in the literature, on what (generically) best practice means, independent of identifying specific individual practices or highlighting failure to follow best practices. We consider categories of security advice, and analyze how they apply over the lifecycle of IoT devices. For concreteness in discussion, we use iterative inductive coding to code and systematically analyze a set of 1013 IoT security best practices, recommendations, and guidelines collated from industrial, government, and academic sources. Among our findings, of all analyzed items, 68% fail to meet our definition of an (actionable) practice, and 73% of all actionable advice relates to the software development lifecycle phase, highlighting the critical position of manufacturers and developers. We hope that our work provides a basis for the community to better understand best practices, identify and reach consensus on specific practices, and find ways to motivate relevant stakeholders to follow them.

Polycystic ovarian syndrome: signs and feedback effects of hyperandrogenism and insulin resistance

Polycystic ovary syndrome (PCOS) is a disease whose diagnosis is based on the detection of hyperandrogenism (HA) and ovulatory dysfunction. Women with PCOS frequently develop insulin resistance (IR), which generates a metabolic condition that involves a decrease in the action of insulin at the cellular level and is linked to compensatory hyperinsulinemia (HI). In PCOS, the ovary remains sensitive to the action of insulin. Additionally, it has been observed that the main effect of insulin in the ovary is the stimulation of androgen synthesis, resulting in HA, one of the fundamental characteristics of the PCOS. In this sense, the excess of androgens favors the development of IR, thus perpetuating the cycle of IR-HI-HA, and therefore PCOS. Moreover, mitochondrial dysfunction is present in PCOS patients and is a common feature in both IR and HA. This review places electron transfer as a key element in HA and IR development, with emphasis on the relationship between androgen biosynthesis and mitochondrial function. Indeed, metformin has been involved in repair mitochondrial dysfunction, decrease of oxidative stress, reduction of androgens levels and the enhancing of insulin sensitivity. Therefore, we propose that treatment with metformin could decrease HI and consequently HA, restoring, at least in part, the metabolic and hormonal disorders of PCOS.

Gene transcription profiling of astheno- and normo-zoospermic sperm subpopulations

Spermatozoa contain a repertoire of RNAs considered to be potential functional fertility biomarkers. In this study, the gene expression of human sperm subpopulations with high (F1) and low (F2) motility from healthy normozoospermic (N) and asthenozoospermic (A) individuals was evaluated using RNA microarray followed by functional genomic analysis of differentially expressed genes. Results from A–F1 versus N–F1, A–F2 versus N–F2, N–F1 versus N–F2, and A–F1 versus A–F2 comparisons showed a considerably larger set of downregulated genes in tests versus controls. Gene ontology (GO) analysis of A–F1 versus N–F1 identified 507 overrepresented biological processes (BPs), several of which are associated with sperm physiology. In addition, gene set enrichment analysis of the same contrast showed 110 BPs, 36 cellular components, and 31 molecular functions, several of which are involved in sperm motility. A leading-edge analysis of selected GO terms resulted in several downregulated genes encoding to dyneins and kinesins, both related to sperm physiology. Furthermore, the predicted activation state of asthenozoospermia was increased, while fertility, cell movement of sperm, and gametogenesis were decreased. Interestingly, several downregulated genes characteristic of the canonical pathway protein ubiquitination were involved in asthenozoospermia activation. Conversely, GO analysis of A–F2 versus N–F2 did not identify overrepresented BPs, although the gene set enrichment analysis detected six enriched BPs, one cellular component, and two molecular functions. Overall, the results show differences in gene transcription between sperm subpopulations from asthenozoospermic and normozoospermic semen samples and allowed the identification of gene sets relevant to sperm physiology and reproduction.

Regulation of anti-tumorigenic pathways by the combinatory treatment of calcitriol and TGF-β in PC-3 and DU145 cells

Calcitriol and transforming growth factors beta (TGF-β) are involved in several biological pathways such as cell proliferation, differentiation, migration and invasion. Their cellular effects could be similar or opposite depending on the genetic target, cell type and context. Despite the reported association of calcitriol deficiency and disruption of the TGF-β pathway in prostate cancer and the well-known independent effects of calcitriol and TGF-βs on cancer cells, there is limited information regarding the cellular effects of calcitriol and TGF-β in combination. In this study, we in vitro analyze the combinatory effects of calcitriol and TGF-β on cell growth and apoptosis using PC-3 and DU145 human prostate cancer cell lines. Using high-throughput microarray profiling of PC-3 cells upon independent and combinatory treatments, we identified distinct transcriptional landscapes of each intervention, with a higher effect established by the combinatorial treatment, following by TGF-β1 and later by calcitriol. A set of genes and enriched pathways converge among the treatments, mainly between the combinatory scheme and TGF-β1, but the majority were treatment-specific. Of note, CYP24A1, IGFBP3, CDKN1A, NOX4 and UBE2D3 were significantly up-regulated upon the combinatorial treatment whereas CCNA1, members of the CT45A and APOBEC3 family were down-regulated. By public RNA signatures, we were able to confirm the regulation by the co-treatment over cell proliferation and cell cycle. We finally investigated the possible clinical impact of genes modulated by the combinatorial treatment using benchmark prostate cancer data. This comprehensive analysis reveals that the combinatory treatment impairs cell growth without affecting apoptosis and their combinatory actions might synergize and improved their individual effects to reprogram prostate cancer signaling.

An organotin indomethacin derivative inhibits cancer cell proliferation and synergizes the antiproliferative effects of lapatinib in breast cancer cells

It is known that an inflammatory condition in different types of cancer provides a sustained microenvironment that favors tumor growth, invasion, and metastasis. Non-steroidal anti-inflammatory drugs such as indomethacin have demonstrated chemo-preventive, anti-proliferative and cytotoxic effects in a variety of tumors. The aim of this study was to investigate the effects of an organotin indomethacin derivative (OID) on the proliferation of breast and prostate cancer cell lines and the possible mechanisms of action of this compound. Different cancer cell lines were treated in the presence of OID and cell proliferation was measured by quantification of the DNA content, changes in the cell cycle profile and the activation of caspase 3 were evaluated by flow cytometry, interleukin 6 (IL-6) gene expression was evaluated by qPCR and protein expression was analyzed by ELISA and Western blot assays. OID inhibited the cell proliferation of a panel of cancer cell lines in a concentration-dependent manner. Moreover, the addition of OID to lapatinib treatment, targeted therapy for breast cancer, significantly enhanced its antiproliferative response. The effects on cell proliferation of these compounds involved, among others, the induction of apoptosis, the downregulation of IL-6 and a decrease of the MAPK activation pathway. Our results suggest that the use of OID alone or in combination with tyrosine kinase inhibitors could be considered as adjuvants in the treatment of cancer.

Multicore optical fiber shape sensors suitable for use under gamma radiation

We have designed and implemented a fiber optic shape sensor for high-energy ionizing environments based on multicore optical fibers. We inscribed two fiber Bragg gratings arrays in a seven-core optical fiber. One of the arrays has been inscribed in a hydrogen-loaded fiber and the other one in an unloaded fiber in order to have two samples with very different radiation sensitivity. The two samples were coiled in a metallic circular structure and were exposed to gamma radiation. We have analyzed the permanent radiation effects. The radiation-induced Bragg wavelength shift (RI-BWS) in the hydrogen-loaded fiber is near ten times higher than the one observed for the unloaded fiber, with a maximum wavelength shift of 415 pm. However, the use of the multiple cores permits to make these sensors immune to RI-BWS obtaining a similar curvature error in both samples of approximately 1 cm without modifying the composition of the fiber, pre-irradiation or thermal treatment.

Sampled true time delay line operation by inscription of long period gratings in few-mode fibers

We propose and experimentally demonstrate distributed microwave photonics signal processing over a few-mode fiber link by implementing 4-sample true time delay line operation. The inscription of a set of long period gratings at specific locations along the few-mode fiber allows the excitation of the higher-order modes while adjusting the individual sample group delays and amplitudes that are required for sampled true time delay line behavior. Since solely the injection of the fundamental mode at the few-mode fiber input is required, we render this signal processing system independent of any preceding fiber link that may be required in addition to distribute the signal. We experimentally validate the performance of the implemented true time delay line when applied to radiofrequency signal filtering.

Steroid hormones and pregnancy

Pregnancy is associated with physiological adjustments in order to allow adequate growth and fetal development. In particular, steroids are necessary to maintain in balance numerous functions during gestation. Steroidogenesis in the maternal, placental and fetal compartments and the biological effects of progestins and estrogens that play a pivotal role before and during pregnancy are described. Although it is well-known that androgens are considered as substrate for estrogens biosynthesis, their biosynthesis and functionality in placental and other tissues have been questioned. As compared with healthy pregnancy, steroid hormones levels have been found altered in complicated pregnancies and hormonal treatments have been used is some pathologies. Therefore, the aim of this work was to review the biosynthesis, function and regulation of progestins, androgens and estrogens during gestation. Furthermore, steroid hormones concentrations during healthy and complicated pregnancy as well hormonal therapies for the prevention of miscarriages and preterm deliveries are discussed in the present review.

A single preovulatory administration of ulipristal acetate affects the decidualization process of the human endometrium during the receptive period of the menstrual cycle

In order to get further information on the effects of ulipristal acetate (UPA) upon the process of decidualization of endometrium, a functional analysis of the differentially expressed genes in endometrium (DEG) from UPA treated-versus control-cycles of normal ovulatory women was performed. A list of 1183 endometrial DEG, from a previously published study by our group, was submitted to gene ontology, gene enrichment and ingenuity pathway analyses (IPA). This functional analysis showed that decidualization was a biological process overrepresented. Gene set enrichment analysis identified LIF, PRL, IL15 and STAT3 among the most down-regulated genes within the JAK STAT canonical pathway. IPA showed that decidualization of uterus was a bio-function predicted as inhibited by UPA. The results demonstrated that this selective progesterone receptor modulator, when administered during the periovulatory phase of the menstrual cycle, may affect the molecular mechanisms leading to endometrial decidualization in response to progesterone during the period of maximum embryo receptivity.

Few-mode fiber true time delay lines for distributed radiofrequency signal processing

We report, for the first time to our knowledge, distributed radiofrequency signal processing built upon true time delay operation on a step-index few-mode fiber. Two 3-sample configurations with different time delay properties are implemented over the same 60-meter 4-LP-mode fiber link. The inscription of a long period grating at a specific fiber position converts part of the LP₀₁ mode into the LP₀₂, permitting sample time delay engineering. Delay line performance is experimentally demonstrated when applied to radiofrequency signal filtering, example of fiber-distributed processing functionality exhibiting one order or magnitude gain in terms of compactness.

Characterization of a FBG sensor interrogation system based on a mode-locked laser scheme

This paper is focused on the characterization of a fiber Bragg grating (FBG) sensor interrogation system based on a fiber ring laser with a semiconductor optical amplifier as the gain medium, and an in-loop electro-optical modulator. This system operates as a switchable active (pulsed) mode-locked laser. The operation principle of the system is explained theoretically and validated experimentally. The ability of the system to interrogate an array of different FBGs in wavelength and spatial domain is demonstrated. Simultaneously, the influence of several important parameters on the performance of the interrogation technique has been investigated. Specifically, the effects of the bandwidth and the reflectivity of the FBGs, the SOA gain, and the depth of the intensity modulation have been addressed.

Chronic moderate ethanol intake differentially regulates vitamin D hydroxylases gene expression in kidneys and xenografted breast cancer cells in female mice

Factors affecting vitamin D metabolism may preclude anti-carcinogenic effects of its active metabolite calcitriol. Chronic ethanol consumption is an etiological factor for breast cancer that affects vitamin D metabolism; however, the mechanisms underlying this causal association have not been fully clarified. Using a murine model, we examined the effects of chronic moderate ethanol intake on tumoral and renal CYP27B1 and CYP24A1 gene expression, the enzymes involved in calcitriol synthesis and inactivation, respectively. Ethanol (5% w/v) was administered to 25-hydroxyvitamin D₃-treated or control mice during one month. Afterwards, human breast cancer cells were xenografted and treatments continued another month. Ethanol intake decreased renal Cyp27b1 while increased tumoral CYP24A1 gene expression.Treatment with 25-hydroxyvitamin D₃ significantly stimulated CYP27B1 in tumors of non-alcohol-drinking mice, while increased both renal and tumoral CYP24A1. Coadministration of ethanol and 25-hydroxyvitamin D₃ reduced in 60% renal 25-hydroxyvitamin D₃-dependent Cyp24a1 upregulation (P<0.05). We found 5 folds higher basal Cyp27b1 than Cyp24a1 gene expression in kidneys, whereas this relation was inverted in tumors, showing 5 folds more CYP24A1 than CYP27B1. Tumor expression of the calcitriol target cathelicidin increased only in 25-hydroxyvitamin D₃-treated non-ethanol drinking animals (P<0.05). Mean final body weight was higher in 25-hydroxyvitamin D₃ treated groups (P<0.001). Overall, these results suggest that moderate ethanol intake decreases renal and tumoral 25-hydroxyvitamin D₃ bioconversion into calcitriol, while favors degradation of both vitamin D metabolites in breast cancer cells. The latter may partially explain why alcohol consumption is associated with vitamin D deficiency and increased breast cancer risk and progression.

Multicore fiber-Bragg-grating-based directional curvature sensor interrogated by a broadband source with a sinusoidal spectrum

A simple, spectral-drift-insensitive interrogation scheme for a multicore fiber Bragg grating (FBG)-based directional curvature sensor is proposed. The basic principle is to transform the wavelength shift of FBGs into the reflected power variation, which is accomplished by utilizing a broadband source with a sinusoidal spectrum. The closed-form expression of the relationship between the reflected power of the FBG and the corresponding peak wavelength is derived for the first time, to the best of our knowledge; therefore, the peak wavelength of the FBG can be precisely interrogated by using a single photodiode. The experimental results show that, with respect to conventional wavelength measurement by an optical spectrum analyzer, the demodulated wavelength error by our proposed interrogation scheme is within ±20  pm. The proposed scheme is further extended to interrogate the direction and curvature using a multicore FBG-based curvature sensor; the interrogated curvature with an error less than 8% is achieved.

Strategies for the quality assessment of the health care service providers in the treatment of Gastric Cancer in Colombia

BACKGROUND

While, at its inception in 1993, the health care system in Colombia was publicized as a paradigm to be copied across the developing world, numerous problems in its implementation have led to, what is now, an inefficient and crisis-ridden health system. Furthermore, as a result of inappropriate tools to measure the quality of the health service providers, several corruption scandals have arisen in the country. This study attempts to tackle this situation by proposing a strategy for the quality assessment of the health service providers (Entidades Promotoras de Salud, EPS) in the Colombian health system. In particular, as a case study, the quality of the treatment of stomach cancer is analyzed.

METHODS

The study uses two complementary techniques to address the problem. These techniques are applied based on data of the treatment of gastric cancer collected on a nation-wide scale by the Colombian Ministry of Health and Welfare. First, Data Envelopment Analysis (DEA) and the Malmquist Index (MI) are used to establish the most efficient EPS's within the system, according to indicators such as opportunity indicators. Second, sequential clustering algorithm, related to process mining a field of data mining, is used to determine the medical history of all patients and to construct typical care pathways of the patients belonging to efficient and inefficient EPS's. Lastly, efforts are made to identify traits and differences between efficient and inefficient EPS's.

RESULTS

Efficient and inefficient EPS were identified for the years 2010 and 2011. Additionally, a Malmquist Index was used to calculate the relative changes in the efficiency of the health providers. Using these efficiency rates, the typical treatment path of patients with gastric cancer was found for two EPSs: one efficient and another inefficient. Finally, the typical traits of the care pathways were established.

CONCLUSIONS

Combining DEA and process mining proved to be a powerful approach understanding the problem and gaining valuable insight into the inner workings of the Colombian Health System, especially in terms of the treatment process performed by health care providers in critical illnesses such as cancer. However, no sufficiently compelling results were found to establish the contribution of such a combination to evaluate the quality in the delivery of health services.

Ulipristal acetate administration at mid-cycle changes gene expression profiling of endometrial biopsies taken during the receptive period of the human menstrual cycle

The aim of this study was to analyze the effects of mid-cycle administration of Ulipristal acetate (UPA) on gene expression in endometrial biopsies taken during the receptive phase of the cycle. Fourteen healthy menstruating women were studied during 14 control non-treated and 12 treated cycles with a single dose of 30 mg UPA when follicle diameter reached 20 mm. Ovulation in both treated and control cycles was confirmed by serial determinations of serum LH, progesterone and vaginal ultrasound. An endometrial biopsy at day LH+7, in each cycle, was taken for RNA microarray and qPCR analysis or prepared for histological and immunohistochemistry studies. Functional analysis of differentially expressed genes showed the presence of changes compatible with a non-receptive endometrial phenotype, further confirmed by qPCR and immunohistochemistry. This study suggests the effects of UPA on endometrial receptivity, offering a plausible explanation for the higher contraceptive efficacy of this method compared to that of levonorgestrel.

Tilted fiber Bragg gratings in multicore optical fibers for optical sensing

We have inscribed a tilted fiber Bragg grating (TFBG) in selected cores of a multicore optical fiber. The presence of the TFBG permits to couple light from the incident-guided mode to the cladding modes and to the neighbor cores, and this interaction can be used for optical sensing. We measured different magnitudes: strain, curvature magnitude and direction, and external refractive index. The curvature results show a linear dependence of the maximum crosstalk with the curvature magnitude with a sensitivity of 2.5  dB/m^-1 as the curvature magnitude increases and at the same time a wavelength shift of 70  pm/m^-1. Changes in the external refractive index gradually vanish the cladding modes resonances and the crosstalk between the different cores, obtaining a reduction of the 90% of the optical spectra integral area for refractive indexes between 1.398 and 1.474.

A time-course regulatory and kinetic expression study of steroid metabolizing enzymes by calcitriol in primary cultured human placental cells

1,25-dihydroxivitamin D₃ (calcitriol), is a secoesteroid involved in several placental functions. In particular, we and others showed that calcitriol regulates peptides, proteins, cytokines and hormones production in human trophoblastic cells. On the other hand, calcitriol modifies the activity and expression of some steroidogenic enzymes, a process that is considered tissue-specific. However, the effects of calcitriol on the expression of enzymes involved in the synthesis of sex steroids in placental tissue have not yet been entirely studied. The aim of the present study was to investigate the effects of calcitriol upon gene expression of several steroid enzymes such as cytochrome P450scc (CYP11A1), type 1 3β-hydroxysteroid dehydrogenase(3β-HSDI), 17β-HSD3, 17α-hydroxylase/17,20 lyase (CYP17A1) and aromatase (CYP19A1) in primary cultures of human placental cells. Cell cultures were performed using placentas obtained immediately after delivery by caesarean section from normotensive healthy women and calcitriol effects were evaluated, at level of transcription, by qPCR. The results showed that: 1) from basal expression values of the five genes studied, 3β-HSDI was the most expressed gene (P<0.05); 2) basal expression of all enzymes was significantly higher in cultured syncytiotrophoblast than in cytotrophoblasts (P<0.05); 3) the presence of calcitriol in cultured trophoblast cells generally resulted in a stimulatory effect of CYP11A1, CYP19A1 and 17β-HSD3 gene expression at 3h of treatment whereas 3β-HSDI was induced at 6h (P<0.05). However, a time-dependent variable was also observed; 4) protein expression of CYP11A1 and 3β-HSDI were not modified significantly by calcitriol, however that of CYP19A1 was regulated in similar fashion as gene expression. In conclusion, calcitriol affected in a time-dependent manner the expression of steroids metabolizing enzymes in human placental cell cultures.

Spatial Division Multiplexed Microwave Signal processing by selective grating inscription in homogeneous multicore fibers

The use of Spatial Division Multiplexing for Microwave Photonics signal processing is proposed and experimentally demonstrated, for the first time to our knowledge, based on the selective inscription of Bragg gratings in homogeneous multicore fibers. The fabricated devices behave as sampled true time delay elements for radiofrequency signals offering a wide range of operation possibilities within the same optical fiber. The key to processing flexibility comes from the implementation of novel multi-cavity configurations by inscribing a variety of different fiber Bragg gratings along the different cores of a 7-core fiber. This entails the development of the first fabrication method to inscribe high-quality gratings characterized by arbitrary frequency spectra and located in arbitrary longitudinal positions along the individual cores of a multicore fiber. Our work opens the way towards the development of unique compact fiber-based solutions that enable the implementation of a wide variety of 2D (spatial and wavelength diversity) signal processing functionalities that will be key in future fiber-wireless communications scenarios. We envisage that Microwave Photonics systems and networks will benefit from this technology in terms of compactness, operation versatility and performance stability.

Evidence of sexual dimorphism in placental vitamin D metabolism: Testosterone inhibits calcitriol-dependent cathelicidin expression

Male fetus and neonates show increased immune vulnerability compared to females, which results in a higher risk of perinatal infections. These differences could partially be due to sex steroids differential modulation of vitamin D metabolism; since calcitriol, the most active vitamin D metabolite, regulates immune responses and transcriptionally induces the antimicrobial peptide cathelicidin in the human placenta. Calcitriol availability depends on CYP27B1 and CYP24A1 expression, the cytochromes involved in its synthesis and degradation, respectively. However, the effects of testosterone upon these enzymes and the final biological outcome upon the calcitriol-dependent immune-target cathelicidin in the placenta have not been studied. In this study we show that testosterone significantly inhibited CYP27B1 while stimulated CYP24A1 gene expression in cultured trophoblasts. These effects were accompanied by CREB activation through cAMP-independent and androgen receptor-dependent mechanisms. Male placental cotyledons showed reduced basal CYP27B1 and cathelicidin gene expression compared to females (P<0.05). Testosterone concentration was higher in the cord blood of male neonates (P=0.007), whereas cathelicidin levels were lesser compared to females (P=0.002). Altogether our results suggest that male placentas produce less cathelicidin due to decreased calcitriol bioavailability. We propose that the observed sex-dependent differences in placental vitamin D metabolism contribute in fetal responses to infections and could partially explain why the increased male fetuses immune vulnerability. Moreover, gestational hyperandrogenemia could adversely affect placental vitamin D metabolism independently of fetal sex.

All-Optical Fiber Hanbury Brown &Twiss Interferometer to study 1300 nm single photon emission of a metamorphic InAs Quantum Dot

New optical fiber based spectroscopic tools open the possibility to develop more robust and efficient characterization experiments. Spectral filtering and light reflection have been used to produce compact and versatile fiber based optical cavities and sensors. Moreover, these technologies would be also suitable to study N-photon correlations, where high collection efficiency and frequency tunability is desirable. We demonstrated single photon emission of a single quantum dot emitting at 1300 nm, using a Fiber Bragg Grating for wavelength filtering and InGaAs Avalanche Photodiodes operated in Geiger mode for single photon detection. As we do not observe any significant fine structure splitting for the neutral exciton transition within our spectral resolution (46 μeV), metamorphic QD single photon emission studied with our all-fiber Hanbury Brown & Twiss interferometer could lead to a more efficient analysis of entangled photon sources at telecom wavelength. This all-optical fiber scheme opens the door to new first and second order interferometers to study photon indistinguishability, entangled photon and photon cross correlation in the more interesting telecom wavelengths.

Synthesis and biological activity of two pregnane derivatives with a triazole or imidazole ring at C-21

Pregnane derivatives are studied as agents for the treatment of different hormone-dependent diseases. The biological importance of these steroids is based on their potential use against cancer. In this study, we report the synthesis, characterization and biological activity of two pregnane derivatives with a triazole (3β-hydroxy-21-(1H-1,2,4-triazol-1-yl)pregna-5,16-dien-20-one; T-OH) or imidazole (3β-hydroxy-21-(1H-imidazol-1-yl)pregna-5,16-dien-20-one; I-OH) moieties at C-21. These derivatives were synthesized from 16-dehydropregnenolone acetate. The activity on cell proliferation of the compounds was measured on three human cancer cells lines: prostate cancer (PC-3), breast cancer (MCF7) and lung cancer (SK-LU-1). The cytotoxic and antiproliferative effects of T-OH and I-OH were assessed by using SBR and XTT methods, respectively. The gene expressions were evaluated by real time PCR. In addition, results were complemented by docking studies and transactivation assays using an expression vector to progesterone and androgen receptor. Results show that the two compounds inhibited the three cell lines proliferation in a dose-dependent manner. Compound I-OH downregulated the gene expression of the cyclins D1 and E1 in PC-3 and MFC7 cells; however, effect upon Ki-67, EAG1, BIM or survivin genes was not observed. Docking studies show poor interaction with the steroid receptors. Nevertheless, the transactivation assays show a weak antagonist effect of I-OH on progesterone receptor but not androgenic or antiandrogenic actions. In conclusion, the synthesized compounds inhibited cell proliferation as well as genes key to cell cycle of PC-3 and MCF7 cell lines. Therefore, these compounds could be considered a good starting point for the development of novel therapeutic alternatives to treat cancer.

Enhancement of the sensitivity of a temperature sensor based on fiber Bragg gratings via weak value amplification

We present a proof-of-concept experiment aimed at increasing the sensitivity of Fiber-Bragg-gratings temperature sensors by making use of a weak-value-amplification scheme. The technique requires only linear optics elements for its implementation and appears as a promising method for increasing the sensitivity than state-of the-art sensors can currently provide. The device implemented here is able to generate a shift of the centroid of the spectrum of a pulse of ∼0.035  nm/°C, a nearly fourfold increase in sensitivity over the same fiber-Bragg-grating system interrogated using standard methods.

Efficacy and mechanism of action of the tyrosine kinase inhibitors gefitinib, lapatinib and neratinib in the treatment of HER2-positive breast cancer: preclinical and clinical evidence

An increasing number of tumors, including breast cancer, overexpress proteins of the epidermal growth factor receptor (EGFR) family. The interaction between family members activates signaling pathways that promote tumor progression and resistance to treatment. Human epidermal growth factor receptor type II (HER2) positive breast cancer represents a clinical challenge for current therapy. It has motivated the development of novel and more effective therapeutic EGFR family target drugs, such as tyrosine kinase inhibitors (TKIs). This review focuses on the effects of three TKIs mostly studied in HER2- positive breast cancer, lapatinib, gefitinib and neratinib. Herein, we discuss the mechanism of action, therapeutic advantages and clinical applications of these TKIs. To date, TKIs seem to be promising therapeutic agents for the treatment of HER2-overexpressing breast tumors, either as monotherapy or combined with other pharmacological agents.

Vitamin D and Inflammatory Cytokines in Healthy and Preeclamptic Pregnancies

Preeclampsia is a pregnancy disease characterized by hypertension and proteinuria. Among several disorders, the imbalance of inflammatory cytokines and the alteration of vitamin D metabolism have been reported in preeclampsia. The effects of calcitriol upon inflammatory cytokines has been demonstrated. In healthy pregnant women there is a shift toward a Th2 cytokine profile, which is necessary for an adequate pregnancy outcome. As compared with normal pregnancy, high pro-inflammatory and low anti-inflammatory cytokine levels have been observed in preeclamptic women. Preeclampsia has been associated with low calcitriol levels and vitamin D deficiency is correlated with a higher risk of the development of this disease. It has been demonstrated that placenta is a source as well as the target of calcitriol and cytokines and placental dysfunction has been associated with preeclampsia. Therefore, the present manuscript includes a review about serum calcitriol levels in non-pregnant, pregnant, and preeclamptic women as well as a review on the fetoplacental vitamin D metabolism in healthy and preeclamptic pregnancies. In addition, circulating and fetoplacental inflammatory cytokines in healthy and preeclamptic pregnancies are reviewed. Finally, the effects of calcitriol upon placental pro-inflammatory cytokines are also explored. In conclusion, maternal and placental calcitriol levels are low in preeclampsia which may explain, at least in part, high pro-inflammatory cytokine levels in this disease.

IL-10 inhibits while calcitriol reestablishes placental antimicrobial peptides gene expression

IL-10 and calcitriol help to achieve a successful pregnancy by suppressing active maternal immunity; however, these factors exert opposite effects upon microbial infections. In the skin and immune cells, IL-10 downregulates β-defensins while calcitriol induces cathelicidin gene expression in various tissues including placenta. Though, the regulation of human placental β-defensins by IL-10 and calcitriol has not been studied. Therefore, we explored the regulation of these antimicrobial peptides expression in cultured placental cells by calcitriol and IL-10 alone and combined. Real time PCR showed that calcitriol stimulated, while IL-10 inhibited, β-defensins and cathelicidin gene expression (P<0.05). In coincubations studies, calcitriol was able to maintain antimicrobial peptides gene expression above control values, overriding IL-10 inhibitory effects. Calcitriol downregulated endogenous IL-10 secretion. Interestingly, calcitriol and TNF-α cooperatively enhanced β-defensins, while TNF-α reduced basal and calcitriol-stimulated cathelicidin gene expression. In summary, calcitriol and IL-10 exerted opposite effects on antimicrobial peptides expression in the human placenta, suggesting that unbalanced production of IL-10 and calcitriol could be deleterious to innate immune responses during gestation. Our results suggest that calcitriol enhancement of placental defenses involves two mechanisms: (1) downregulation of IL-10 secretion and (2) direct upregulation of β-defensins and cathelicidin gene expression. Considering that IL-10 and calcitriol differentially regulate the innate immune response in the placenta, in the case of an infection, calcitriol might restrict IL-10 permissive actions towards microbial invasion while restrains inflammation, allowing for pregnancy to continue in quiescence. These results strongly advice maternal vitamin D sufficiency during pregnancy.

Time and frequency pump-probe multiplexing to enhance the signal response of Brillouin optical time-domain analyzers

A technique to enhance the response and performance of Brillouin distributed fiber sensors is proposed and experimentally validated. The method consists in creating a multi-frequency pump pulse interacting with a matching multi-frequency continuous-wave probe. To avoid nonlinear cross-interaction between spectral lines, the method requires that the distinct pump pulse components and temporal traces reaching the photo-detector are subject to wavelength-selective delaying. This way the total pump and probe powers launched into the fiber can be incrementally boosted beyond the thresholds imposed by nonlinear effects. As a consequence of the multiplied pump-probe Brillouin interactions occurring along the fiber, the sensor response can be enhanced in exact proportion to the number of spectral components. The method is experimentally validated in a 50 km-long distributed optical fiber sensor augmented to 3 pump-probe spectral pairs, demonstrating a signal-to-noise ratio enhancement of 4.8 dB.

In vivo dual targeting of the oncogenic Ether-à-go-go-1 potassium channel by calcitriol and astemizole results in enhanced antineoplastic effects in breast tumors

Background

The oncogenic ether-à-go-go-1 potassium channel (EAG1) activity and expression are necessary for cell cycle progression and tumorigenesis. The active vitamin D metabolite, calcitriol, and astemizole, a promising antineoplastic drug, target EAG1 by inhibiting its expression and blocking ion currents, respectively. We have previously shown a synergistic antiproliferative effect of calcitriol and astemizole in breast cancer cells in vitro, but the effect of this dual therapy in vivo has not been studied.

Methods

In the present study, we explored the combined antineoplastic effect of both drugs in vivo using mice xenografted with the human breast cancer cell line T-47D and a primary breast cancer-derived cell culture (MBCDF). Tumor-bearing athymic female mice were treated with oral astemizole (50 mg/kg/day) and/or intraperitoneal injections of calcitriol (0.03 μg/g body weight twice a week) during 3 weeks. Tumor sizes were measured thrice weekly. For mechanistic insights, we studied EAG1 expression by qPCR and Western blot. The expression of Ki-67 and the relative tumor volume were used as indicators of therapeutic efficacy.

Results

Compared to untreated controls, astemizole and calcitriol significantly reduced, while the coadministration of both drugs further suppressed, tumor growth (P < 0.05). In addition, the combined therapy significantly downregulated tumoral EAG1 and Ki-67 expression.

Conclusions

The concomitant administration of calcitriol and astemizole inhibited tumor growth more efficiently than each drug alone, which may be explained by the blocking of EAG1. These results provide the bases for further studies aimed at testing EAG1-dual targeting in breast cancer tumors expressing both EAG1 and the vitamin D receptor.

Regulation of CYP27B1 and CYP24A1 gene expression by recombinant pro-inflammatory cytokines in cultured human trophoblasts

Placenta is an important source of endocrine and immunological factors. During pregnancy, calcitriol, the active metabolite of vitamin D, is also metabolized by decidua and placental tissue by means of CYP27B1 and CYP24A1 for synthesis and inactivation of calcitriol respectively. Calcitriol production is regulated by several factors in a tissue-specific manner. However, the association of pro-inflammatory cytokines on calcitriol metabolism has not been studied in human placenta. The aim of the present study was to investigate the effects of TNF-α, INF-γ, IL-6 and IL-1β upon CYP27B1 and CYP24A1 gene expression in primary cultures of human placental cells. Placentas were obtained immediately after delivery by cesarean section from normotensive women. Cytokine effects upon mRNA of CYPs in enriched trophoblastic cell preparations were evaluated by using qPCR. The results showed that incubation of trophoblasts in the presence of each cytokine resulted in a significant increase of both CYPs expression. Interestingly, TNF-α increased significantly the ratio of CYP24A1/CYP27B1 gene expression, while IFN-γ preferentially induced CYP27B1, whereas IL-1β and IL-6 stimulated gene expression of both CYPs in the same proportion. The results suggest that cytokines among other factors regulate calcitriol metabolism in human placenta; specifically, INF-γ may contribute to calcitriol production while TNF-α favors its catabolism.

Temperature gradient sensor based on a long-fiber Bragg grating and time-frequency analysis

A photonic sensor based on a 10-cm-long fiber Bragg grating (FBG) is presented and experimentally validated that is dedicated to detect the presence and the position of a temperature gradient. The system is based on the measurement of the central frequency distribution of the grating based on time-frequency domain analysis. A short optical pulse, having duration much shorter than the transit time along the grating, is coupled into the FBG, and the back-reflected pulse is scanned by means of an oscilloscope. A spatial resolution of 1 mm, given by half the input pulse duration, is achieved. The proposed sensor is based on a simple configuration and presents a sensing range of 10 cm, which could be further enhanced by fabricating a longer grating.

Calcitriol reduces thrombospondin-1 and increases vascular endothelial growth factor in breast cancer cells: implications for tumor angiogenesis

Calcitriol, a potent antineoplastic vitamin D metabolite, inhibits proliferation, induces apoptosis and slows the growth of tumors. Calcitriol also may exert either antiangiogenic or proangiogenic effects depending on the tissue. Vascular endothelial growth factor (VEGF) and thrombospondin-1 (Tsp-1) are key factors involved in promoting and inhibiting angiogenesis, respectively. The effects of calcitriol on Tsp-1 have not been studied in the mammary gland, while VEGF regulation is not clear, since opposite outcomes have been demonstrated. Therefore, the present study was undertaken to investigate the effects of calcitriol on VEGF and Tsp-1 expression in primary breast tumor-derived cells and a panel of established breast cancer cell lines. In vivo studies in athymic mice were also performed in order to gain further insight into the biological effects of calcitriol on angiogenesis. Real time-PCR and ELISA analyses showed that calcitriol stimulated VEGF mRNA expression and protein secretion while elicited the opposite effect on Tsp-1 in 7 out of 8 cell lines studied, independently of the cell phenotype (P<0.05 in n=5). In vivo, calcitriol significantly inhibited the relative tumoral volume after 4 weeks of treatment; however, serum VEGF was higher in calcitriol-treated animals compared to controls (P<0.05). The integrated fluorescence intensity analysis of CD31, a vessel marker, showed that xenografted breast cancer cells developed tumors with similar vascular density regardless of the treatment. Nevertheless, larger necrotic areas were observed in the tumors of calcitriol-treated mice compared to controls. Since the antineoplastic activity of calcitriol has been consistently demonstrated in several studies including this one, our results suggest that the antitumoral effect of calcitriol in vivo involve different mechanisms not necessarily related to the inhibition of tumor vascularization. Overall, our findings indicate that calcitriol can impact the angiogenic process in breast cancer by regulating VEGF and Tsp-1 expression. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

Placental calcitriol synthesis and IGF-I levels in normal and preeclamptic pregnancies

Placenta is an extrarenal source of calcitriol and pregnancy is associated with increased maternal serum levels of this hormone. It has been reported that insulin-like growth factor I (IGF-I) stimulates placental calcitriol synthesis and that circulating levels of both hormones are low in preeclampsia. Since calcitriol production has not been determined in placental homogenates in preeclampsia, the aim of the present study was to establish if placental calcitriol synthesis and IGF-I concentration are altered in this tissue obtained from preeclamptic pregnancies. Placental samples were obtained from 8 preeclamptic (PE group) and 8 normotensive (NT group) pregnant women. Calcitriol synthesis was determined using [(3)H]-25(OH)D3 (2.94nM) as precursor and [(3)H]-1,25(OH)2D3 produced was calculated as the percentage of radioactivity co-eluting with unlabelled 1,25(OH)2D3 after two successive high pressure liquid chromatographies. Placental IGF-I levels were determined by RIA. In addition, maternal and umbilical calcitriol and IGF-I levels were also determined in these 2 groups using radioreceptor assay and RIA, respectively. The results of the present study showed that placentas from both groups were able to convert [(3)H]-25(OH)D3 into more polar metabolites. In the PE group, placental [(3)H]-1,25(OH)2D3 synthesis was significantly lower than in the NT group (19.6±6.2 vs 29.9±8.1fmoles/200mg wet weight, P=0.013). Regarding IGF-I, its levels were significantly lower in placentas of the PE group than in the NT group (15.2±3.9 vs 21.6±4.9ng/g wet weight, P=0.012). Maternal and umbilical calcitriol levels were significantly lower in the PE than in the NT group (P<0.001). In the PE group, serum IGF-I levels were significantly lower only in the maternal circulation (P<0.05). In conclusion, placental calcitriol synthesis and IGF-I levels are low in preeclampsia which may contribute to decreased local placental functions related to these two hormones and/or to decreased maternal and fetal pool of 1,25(OH)2D3 during preeclamptic pregnancies. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

Calcitriol restores antiestrogen responsiveness in estrogen receptor negative breast cancer cells: a potential new therapeutic approach

BACKGROUND

Approximately 30% of breast tumors do not express the estrogen receptor (ER) α, which is necessary for endocrine therapy approaches. Studies are ongoing in order to restore ERα expression in ERα-negative breast cancer. The aim of the present study was to determine if calcitriol induces ERα expression in ER-negative breast cancer cells, thus restoring antiestrogen responses.

METHODS

Cultured cells derived from ERα-negative breast tumors and an ERα-negative breast cancer cell line (SUM-229PE) were treated with calcitriol and ERα expression was assessed by real time PCR and western blots. The ERα functionality was evaluated by prolactin gene expression analysis. In addition, the effects of antiestrogens were assessed by growth assay using the XTT method. Gene expression of cyclin D1 (CCND1), and Ether-à-go-go 1 (EAG1) was also evaluated in cells treated with calcitriol alone or in combination with estradiol or ICI-182,780. Statistical analyses were determined by one-way ANOVA.

RESULTS

Calcitriol was able to induce the expression of a functional ERα in ER-negative breast cancer cells. This effect was mediated through the vitamin D receptor (VDR), since it was abrogated by a VDR antagonist. Interestingly, the calcitriol-induced ERα restored the response to antiestrogens by inhibiting cell proliferation. In addition, calcitriol-treated cells in the presence of ICI-182,780 resulted in a significant reduction of two important cell proliferation regulators CCND1 and EAG1.

CONCLUSIONS

Calcitriol induced the expression of ERα and restored the response to antiestrogens in ERα-negative breast cancer cells. The combined treatment with calcitriol and antiestrogens could represent a new therapeutic strategy in ERα-negative breast cancer patients.

Time resolved emission at 1.3 μm of a single InAs quantum dot by using a tunable fibre Bragg grating

Photoluminescence and time resolved photoluminescence from single metamorphic InAs/GaAs quantum dots (QDs) emitting at 1.3 μm have been measured by means of a novel fibre-based characterization set-up. We demonstrate that the use of a wavelength tunable fibre Bragg grating filter increases the light collection efficiency by more than one order of magnitude as compared to a conventional grating monochromator. We identified single charged exciton and neutral biexciton transitions in the framework of a random population model. The QD recombination dynamics under pulsed excitation can be understood under the weak quantum confinement potential limit and the interaction between carriers at the wetting layer and QD states.

Long fiber Bragg grating sensor interrogation using discrete-time microwave photonic filtering techniques

A novel technique for interrogating photonic sensors based on long fiber Bragg gratings (FBGs) is presented and experimentally demonstrated, dedicated to detect the presence and the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics (MWP) filters. The long FBGs are used as quasi-distributed sensors. Several hot-spots can be detected along the FBG with a spatial accuracy under 0.5 mm using a modulator and a photo-detector (PD) with a modest bandwidth of less than 1 GHz. The proposed interrogation system is intrinsically robust against environmental changes.

Associations between insulin-like growth factor I, vascular endothelial growth factor and its soluble receptor 1 in umbilical serum and endothelial cells obtained from normotensive and preeclamptic pregnancies

The aim of this study was to investigate the associations between insulin-like growth factor I (IGF-I) with vascular endothelial growth factor (VEGF) and its soluble receptor 1 (sFlt-1) in umbilical serum and to study the effects of IGF-I upon sFlt-1 synthesis in human umbilical vein endothelial cells (HUVEC) in normotensive (NT) and preeclamptic (PE) pregnancies. As compared with the NT group, umbilical serum IGF-I and VEGF levels were lower in the PE group, while sFlt-1 concentrations were higher. Levels of sFlt-1 correlated with IGF-I in the NT group and with VEGF in the PE group. Basal concentration of sFlt-1 in HUVEC culture media was higher in the PE group. IGF-I stimulated sFlt-1 synthesis only in the NT group. In summary, umbilical serum sFlt-1 is associated with IGF-I in normotensive pregnancy and with VEGF in preeclampsia. IGF-I stimulates sFlt-1 synthesis in endothelial cells in normotensive but not in PE pregnancies.

Time-frequency analysis of long fiber Bragg gratings with low reflectivity

A new technique to investigate the spatial distribution of the reflection spectrum along fabricated long weak fiber Bragg gratings (FBG) is experimentally demonstrated, together with its potential applications for distributed fiber sensing and broadband signal processing. A short pulsed coherent light signal is launched into a FBG and the signal frequency is scanned through the FBG reflection spectrum. When the pulse duration is set much shorter than the transit time through the grating a time-resolved reflected signal can be obtained for each signal frequency. It informs about the distribution of the refractive index periodic perturbation along the entire FBG length, hence the uniformity or frequency chirp information of the fabricated FBG. This technique has been implemented to demonstrate a distributed temperature sensing system with high spatial resolution and to also realize a robust all-fiber tunable delay line for broadband signals.

The glycan structure in recombinant human FSH affects endocrine activity and global gene expression in human granulosa cells

The aim of this study was to analyse the biological response to different recombinant human FSH (rhFSH) glycosylation variants on the endocrine activity and gene expression at whole-genome scale in human granulosa-like tumor cell line, KGN. The effects of differences in rhFSH sialylation and oligosaccharide complexity were determined on steroid hormone and inhibin production. A microarray approach was used to explore gene expression patterns induced by rhFSH glycosylation variants. Set enrichment analysis revealed that hormone sialylation and oligosaccharide complexity in rhFSH differentially affected the expression of genes involved in essential biological processes and molecular functions of KGN cells. The relevance of rhFSH oligosaccharide structure on steroidogenesis was confirmed assessing gene expression by real time-PCR. The results demonstrate that FSH oligosaccharide structure affects expression of genes encoding proteins, growth factors and hormones essential for granulosa cells function.

Abstract P6-04-29: Vitamin D induces expression of estrogen receptor and restores endocrine therapy response in estrogen receptor-negative breast cancer

Background: Approximately 30% of all breast tumors do not express estrogen receptor (ER) and patients with these tumors present poor prognosis and respond poorly to hormone therapy. Calcitriol through its vitamin D receptor (VDR) exerts antiproliferative, apoptotic and pro-differentiating effects in cancer. Calcitriols effects upon ER expression in breast cancer cells is controversial. Therefore, in order to clarify this issue, the aim of the present study was to determine if calcitriol induces ERα expression in ERα-negative breast cancer cells and could restore antiestrogen responses. The evaluation of calcitriol effects was performed in terms of proliferation and regulation of the following genes: Cyclin D1, involved in cell cycle, and Ether-à-go-go 1 (Eag1), related to cell proliferation and tumor progression.

Methods: Cultured cells derived from ERα-negative breast tumors and an established ERα-negative breast cancer cell line (SUM 229) were used in this study. These cells were treated with calcitriol and reverse transcription-PCR or western blotting analyses were performed to assess ERα expression. Growth assays with XTT were used to evaluate the antiproliferative response to the antiestrogens fulvestran and tamoxifen. Gene expression analysis for Cyclin D1 and Eag1 was evaluated by real time PCR in cells treated simultaneously with calcitriol plus estradiol or fulvestran.

Results: The treatment with calcitriol in ER-negative breast cancer cells resulted in the induction of ERα. This effect was specifically mediated through the vitamin D3 receptor (VDR), since the VDR antagonist TEI-9647 effectively inhibited the ability of calcitriol to stimulate ERα gene expression. Consequently, the induction of ERα by calcitriol restores the response to antiestrogens in breast cancer cells by inhibiting cell proliferation. Co-treatment of calcitriol and antiestrogens down-regulated Cyclin D1 and Eag1 gene expression.

Conclusion: Calcitriol induced the expression of ERα and restored antiestrogenic responses in ERα-negative breast cancer cells. Moreover, fulvestran down regulated mRNA expression of Cyclin D1 and Eag1 when ERα-negative cells were pre-treated with calcitriol. These results suggest that the combined treatment with calcitriol and antiestrogens could be a new therapeutic strategy for ERα-negative breast cancer patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-29.