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The progression of osteoarthritis (OA) requires the involvement of inflammation, in which chondrocyte damage plays a significant role. Hydroxysafflor yellow A (HSYA), the main active component in the medical and edible dual‐purpose plant safflower, has previously shown anti‐inflammatory effects in various diseases. However, the specific impact of HSYA on OA remains unclear. Here, we investigate the potential role and underlying mechanism of HSYA in chondrocyte damage during the progression of OA. The viability of C28/I2 and iCell‐0092a chondrocytes was measured by CCK8 assay at different concentrations (2.5, 10, 40, and 160 μM). The gene expression of the extracellular matrix was revealed by q‐PCR 24 h after IL‐1β treatment. ROS production and levels of pro‐inflammatory cytokines in C28/I2 cells treated with HSYA were measured by immunoflurescence stating and q‐PCR. The impact of HSYA on the extracellular matrix and inflammation in IL‐1β‐induced OA were detected by western blot, q‐PCR, and immunofluorescence staining. We assessed the effect of HSYA and NF‐κB signaling pathway‐related genes by bioinformatics analysis and conducted molecular docking to assess the interaction of HSYA with a combined protein residue molecule ligand. Western blot was employed to investigate NF‐κB transcription factors in chondrocyte metabolism. HSYA was found to reduce excessive ROS production induced by IL‐1β stimuli, inhibit the expression of matrix metalloproteinase 13, interleukin 6, and tumor necrosis factor‐α, and increase the expression of Type II collagen and SRY‐box transcription factor 9 (p <.05). Mechanistically, HSYA interacted with nuclear factor κB, inhibiting the nuclear translocation and phosphorylation level of NF‐κB p65, and decreasing the phosphorylation and degradation of IκBα (p <.05). In conclusion, HSYA ameliorates inflammation and cartilage damage in OA by inhibiting the NF‐κB pathway, suggesting its potential application as a therapeutic agent for OA treatment. [ABSTRACT FROM AUTHOR]

The geroscience hypothesis proposes that addressing the biology of aging could directly prevent the onset or mitigate the severity of multiple chronic diseases. Understanding the interplay between key aspects of the biological hallmarks of aging is essential in delivering the promises of the geroscience hypothesis. Notably, the nucleotide nicotinamide adenine dinucleotide (NAD) interfaces with several biological hallmarks of aging, including cellular senescence, and changes in NAD metabolism have been shown to be involved in the aging process. The relationship between NAD metabolism and cellular senescence appears to be complex. On the one hand, the accumulation of DNA damage and mitochondrial dysfunction induced by low NAD+ can promote the development of senescence. On the other hand, the low NAD+ state that occurs during aging may inhibit SASP development as this secretory phenotype and the development of cellular senescence are both highly metabolically demanding. However, to date, the impact of NAD+ metabolism on the progression of the cellular senescence phenotype has not been fully characterized. Therefore, to explore the implications of NAD metabolism and NAD replacement therapies, it is essential to consider their interactions with other hallmarks of aging, including cellular senescence. We propose that a comprehensive understanding of the interplay between NAD boosting strategies and senolytic agents is necessary to advance the field. [ABSTRACT FROM AUTHOR]

Introduction. Pseudoangiomatous stromal hyperplasia (PASH) presenting as gigantomastia is rare in pregnancy but can result in severe clinical consequences for both mother and fetus. Case Presentation. A 43-year-old female with a history of biopsy-proven bilateral PASH presented at 22 3/7 weeks gestation with massive bilateral breast enlargement that was symptomatic. After multidisciplinary care, she underwent bilateral mastectomies and delivered at term with no additional complications. Conclusion. Pregnant women who undergo mastectomies for PASH-induced gigantomastia during their second trimesters will likely recover quickly, and fetal risks are low. Given the rarity of this breast entity, management guidelines are sparse. Our case report is an effort to comprehensively review this condition and share the clinical recommendations made by our institution's multidisciplinary team. [ABSTRACT FROM AUTHOR]

Objective: Our aim was to explore whether general practitioners (GPs) communicate with cancer patients on complementary and integrative medicine (CIM) in a patient‐centred and case‐specific manner. Methods: We designed two cases of standardised breast cancer patients and allocated 29 GPs to hold a consultation either with Case 1 or Case 2. Case 1 presented with fears of possible physical side effects of hormone treatment. Case 2 feared a loss in social functioning because of nausea and emesis as possible side effects of chemotherapy. Consultations were audiotaped and analysed using the Roter Interaction Analysis System (RIAS). We analysed whether recommended CIM treatments and GPs' focus on psychosocial or medical and therapy‐related content differed according to whether they were counselling Case 1 or Case 2. Results: In consultations with Case 1, GPs rather focused on medical and therapy‐related content and most often recommended mistletoe, diets and sports. In contrast, GPs focused on psychosocial content and they most often recommended methods of self‐care when counselling Case 2. Conclusion: The GPs in our sample reacted case‐specifically to the patients' interest in CIM. Such responsive and patient‐centred communication is a valuable resource but is often time‐consuming. Adequate training and reimbursement should therefore be considered for GPs. [ABSTRACT FROM AUTHOR]

Ischemic stroke (IS) is one of the leading causes of disability and mortality worldwide. This study aims to find the crucial exosomal miRNAs associated with IS by using bioinformatics methods, reveal potential biomarkers for IS, and investigate the association between the identified biomarker and immune cell pattern in the peripheral blood of IS patients. In this study, 3 up-regulated miRNAs (hsa-miR-15b-5p, hsa-miR-184, and hsa-miR-16-5p) miRNAs in the serum exosomes between IS patients and healthy controls from GEO database (GSE199942) and 25 down-regulated genes of peripheral blood mononuclear cells of IS patients from GSE22255 were obtained with the help of the R software. GO annotation and KEGG pathway enrichment analysis showed that the 25 down-regulated genes were associated with coenzyme metabolic process and were mainly enriched in the N-glycan biosynthesis pathway. Furthermore, we performed the LASSO algorithm to narrow down the above 25 intersected genes, and identified 8 key genes which had a good diagnostic value in discriminating IS patients from the healthy controls analyzed with ROC curve. CIBERSORT algorithm indicated that the abundance of M0 macrophages and resting mast cells was significantly lower than that of the control group. The spearman correlation analysis showed that STT3A was negatively correlated with the proportion of follicular helper T cells, activated NK cells and resting dendritic cells. Finally, GSE117064 showed that has-miR-16-5p was more advantageous for diagnosing stroke. In conclusion, hsa-miR-15b-5p, hsa-miR-184, and hsa-miR-16-5p are identified as specific related exosomal miRNAs for IS patients. These genes may provide new targets for the early identification of IS. [ABSTRACT FROM AUTHOR]

Introduction. Breast cancer is considered nowadays the most prevalent cancer worldwide. The molecular era has successfully divided breast cancer into subtypes based on the various hormonal receptors. These molecular subtypes play a major role in determining the neoadjuvant chemotherapy to be administered. It was noted that the use of neoadjuvant chemotherapy was associated with higher achievement of pathological complete response. The aim of the study was to determine the predictive role of breast cancer subtypes in the efficacy and prognosis of neoadjuvant chemotherapy regimens. Methods. Combining dose dense anthracycline-based, regular dose anthracycline-based, and nonanthracycline-based chemotherapy, we observed data from 87 patients with breast cancer who received surgery after administration of neoadjuvant chemotherapy at our institution between January 2015 and July 2018. The patients were classified into luminal A, luminal B, HER2 overexpression, and triple negative breast cancer as well as low Ki67 (≤14%) and high Ki67 (>14%) expression groups using immunohistochemistry. Pathologic complete response was the only neoadjuvant chemotherapy outcome parameter. To evaluate variables associated with pathologic complete response, we used univariate analyses followed by multivariate logistic regression. Results. 87 patients with breast cancer were classified into different subtypes according to the 12th St. Gallen International Breast Cancer Conference. The response rate to neoadjuvant chemotherapy was significantly different (p = 0.046) between the subgroups. There were significant correlations between pathological complete response (pCR) and ER status (p < 0.0001), HER2 (p = 0.013), molecular subtypes (p = 0.018), T stage (p = 0.024), N stage before chemotherapy (p = 0.04), and type of chemotherapy (p = 0.029). Luminal B type patients had the lowest pCR, followed by luminal A type patients. Conclusion. Evaluating molecular subtype's significance in breast cancer prognosis warrants additional studies in our region with extensive data about patient-specific neoadjuvant chemotherapy regimens. Our study was able to reproduce results complementary to those present in the literature in other outcomes. [ABSTRACT FROM AUTHOR]

Background: Different genetic variants in hormone‐regulating pathways have been identified to influence the risk of breast cancer. This study aimed to evaluate the association of CYP19A1 rs10046 and rs700519 polymorphisms with the risk, clinicopathological factors and prognosis of breast cancer. Methods: In a case‐control study, rs10046 and rs700519 polymorphisms were genotyped using ARMS‐PCR and high‐resolution melting (HRM), respectively, in a total of 702 females. Statistical analysis and evaluation of haplotypes and linkage disequilibrium were performed using SPSS v16, PHASE and 2LD. Results: Although no association of rs700519 with breast cancer was observed, rs10046 in different genetic models as well as C‐C/C‐T and C‐C/C‐C diplotypes, revealed the association with the risk of breast cancer (p < 0.05). Moreover, the rs700519‐C allele was shown to be associated with longer overall survival. In contrast, the T‐T haplotype conferred s a shorter overall survival. rs700519‐C allele was also significantly associated with menarche age. Conclusion: Based on the identified independent association between CYP19A1 diplotypes and rs700519‐C allele with the risk and prognosis of the disease, the gene region and its genetic variants may have a diagnostic and prognostic role in breast cancer development. Further confirmation using other variants in this locus can validate these findings. [ABSTRACT FROM AUTHOR]

Bone mass increases after error‐loading, even in the absence of osteocytes. Loaded osteoblasts may produce a combination of growth factors affecting adjacent osteoblast differentiation. We hypothesized that osteoblasts respond to a single load in the short‐term (minutes) by changing F‐actin stress fiber distribution, in the intermediate‐term (hours) by signaling molecule production, and in the long‐term (days) by differentiation. Furthermore, growth factors produced during and after mechanical loading by pulsating fluid flow (PFF) will affect osteogenic differentiation. MC3T3‐E1 pre‐osteoblasts were either/not stimulated by 60 min PFF (amplitude, 1.0 Pa; frequency, 1 Hz; peak shear stress rate, 6.5 Pa/s) followed by 0–6 h, or 21/28 days of post‐incubation without PFF. Computational analysis revealed that PFF immediately changed distribution and magnitude of fluid dynamics over an adherent pre‐osteoblast inside a parallel‐plate flow chamber (immediate impact). Within 60 min, PFF increased nitric oxide production (5.3‐fold), altered actin distribution, but did not affect cell pseudopodia length and cell orientation (initial downstream impact). PFF transiently stimulated Fgf2, Runx2, Ocn, Dmp1, and Col1⍺1 gene expression between 0 and 6 h after PFF cessation. PFF did not affect alkaline phosphatase nor collagen production after 21 days, but altered mineralization after 28 days. In conclusion, a single bout of PFF with indirect associated release of biochemical factors, stimulates osteoblast differentiation in the long‐term, which may explain enhanced bone formation resulting from mechanical stimuli. [ABSTRACT FROM AUTHOR]

Purposes: Clinical trial education has not been extensively integrated into nursing education systems. Acute care nurses may lack sufficient knowledge when caring for admitted trial patients, which may negatively influence their attitudes toward clinical trials. The aim of this study was to explore ward‐based nurses' knowledge and attitudes toward clinical trials. Design and Methods: Ward‐based nurses working in medical, surgical, and intensive care units in a medical center in Taiwan were approached to complete a questionnaire. The questionnaire was developed by the research team and included four parts: demographics, experience with clinical trials, clinical trial knowledge, and attitudes toward clinical trials. Findings: A total of 161 nurses responded. Nearly 90% of the nurses accessed trial information in their workplace. Nearly 80% of the respondents had experience with caring for trial patients, but the mean score of clinical trial knowledge was 4.5 out of a possible score of 10. For attitudes toward clinical trials, the mean score for positive beliefs was 39.7, and the mean score for negative expectations was 42.5, both out of a possible score of 55. The results indicated that respondents typically tended to hold a negative attitude toward clinical trials, especially in regard to the side effects of study drugs and communication with investigators. Conclusions: Knowledge deficits of ward‐based nurses concerning trial participation is apparent. Continuing education for ward‐based nurses is necessary to promote implementation of clinical trials and reduce negative expectations related to clinical trials. Clinical Relevance: One way to improve nurses' knowledge is to integrate clinical trial education into nursing education systems, which will provide more channels through which nurses can understand how a trial works, including the risks, benefits, and participant protection. Through such educational initiatives, ward‐based nurses may develop more positive beliefs regarding clinical trials and provide higher quality clinical trial care to participants. [ABSTRACT FROM AUTHOR]

Background. Circulating angiogenic cells (CAC) have been identified as important regulators of vascular biology. However, there is still considerable debate about the genotype and function of CAC. Methods and Results. Data from publicly available gene expression data sets were used to analyse the transcriptome of in vitro cultured CAC (CACiv). Genes and pathways of interest were further evaluated using qPCR comparing CACiv versus CD14+ monocytic cells. The CACiv transcriptome strongly related to tissue macrophages, and more specifically to regulatory M2c macrophages. The cytokine expression profile of CACiv was predominantly immune modulatory and resembled the cytokine expression of tumor-associated macrophages (TAM). Pathway analysis revealed previously unrecognized biological processes in CACiv, such as riboflavin metabolism and liver X receptor (LXR)/retinoid X receptor (RXR) and farnesoid X receptor (FXR)/retinoid X receptor (RXR) pathways. Analysis of endothelial-specific genes did not show evidence for endothelial transdifferentiation. Conclusions. CACiv are genotypically similar to regulatory M2c macrophages and lack signs of endothelial differentiation. [ABSTRACT FROM AUTHOR]

Objectives: Successful breastfeeding, crucial for a child's development, depends on a woman's ability to initiate lactation, milk yield, and composition. Those traits differ among women, but the cause and physiological mechanisms responsible for this variation are not fully understood yet. Growing evidence shows that lactation and milk composition vary among women and depend on maternal traits. The aim of this study was to test whether breast volume and its changes during pregnancy are related to the nutritional quality of breastmilk and to breastfeeding dynamics. Material and Methods: Almost 93 pregnant women (mean age: 29.67 ± 3.65), participated in the longitudinal study. Breast measurement was performed at each pregnancy trimester using 3D scanning. Milk samples were collected in the beginning of the second month of lactation from 69 women. Milk macronutrient and calorie content were measured. Women were also interviewed on breastfeeding time and frequency. Results: Breast volume changes during pregnancy were not related to the probability of establishing successful lactation, milk calorie, fat and protein content. We found a negative correlation between milk lactose content and breast volume in the second and third trimester but not with breast volume change. Maternal breast volume in pregnancy was also positively related to the total breastfeeding time (per 24 hr). Conclusions: The results are in line with the notion that milk macronutrient content tends to be weakly associated with various maternal factors and adverse conditions. However, maternal breast volume and its changes during pregnancy are related with time spent breastfeeding per day, what suggests a positive correlation between breast volume in pregnancy and milk yield. [ABSTRACT FROM AUTHOR]

Despite recent advances in chemotherapy and surgical resection, the 5-year survival rate of esophageal cancer still remains at the low level. Therefore, it is very important to discover a new agent to improve the life expectancy of patients with esophageal cancer. Dihydroartemisinin (DHA), a semisynthetic derivative of artemisinin, has recently exhibited promising anticancer activity against various cancer cells. But so far, the specific mechanism remains unclear. We have previously demonstrated that DHA reduced viability of esophageal cancer cells in a dose-dependent manner in vitro and induced cell cycle arrest and apoptosis. Here, we extended our study to further observe the efficacy of DHA on esophageal cancer cells in vivo. In the present study, for the first time, we found that DHA significantly inhibits cell proliferation in xenografted tumor compared with the control. The mechanism was that DHA induced cell apoptosis in both human esophageal cancer cell lines Eca109 and Ec9706 in vivo in a dose-dependent manner. The results suggested that DHA was a promising agent against esophageal cancer in the clinical treatment. [ABSTRACT FROM AUTHOR]

Drought stress significantly declines crop yield. Efficient soil moisture management and its consequent effects on metabolic changes which happen in response to drought stress are important in dry regions agriculture. This research was performed to evaluate yield, yield components, and oil accumulation in safflower (Carthamus tinctorius L.) cultivars seed in response to water deficit conditions. A field experiment was conducted at the Research Farm of the College of Agriculture, Tabriz University during two growing seasons of 2014 and 2015. The treatments were arranged as split plots based on randomized complete block design with three replicates. Irrigation treatments (irrigation after 70, 100, 130, and 160 mm evaporation from class A pan) were assigned to the main plots and spring safflower cultivars (Faraman, Goldasht, Sina, and Soffeh) were allocated to the subplots. Safflower seeds were harvested in 5-d intervals at seven stages during development and maturity period. The result showed that Sina cultivar had the highest seed yield per unit area. Maximum oil percentage of safflower seeds was obtained at 1 to 12 d after plant physiological maturity. Water stress caused seed oil percentage decline across all cultivars. Sina and Faraman cultivars had higher oil percentage across all irrigation treatments. The highest oil and seed yield per unit area under both full and limited irrigation conditions was produced by Sina cultivar. Drought stress decreased seed yield, yield components, and oil content across all safflower cultivars, however, the extent of the damage was limited due to cultivar genetic characteristics and ecological origin. [ABSTRACT FROM AUTHOR]

Low-level laser therapy (LLLT) is known to enhance mitochondrial electron transfer and ATP production; thus, this study asked whether LLLT could stimulate the oxidative burst in human neutrophils (PMN) and improve their ability to kill microorganisms. Blood from healthy human subjects was collected and PMN were isolated from the samples. PMN were treated in vitro with 660 nm or 780 nm CW laser light at 40 mW power and increasing energies up to 19.2 J and were subsequently incubated with Candida albicans cells. Generation of hydroxyl radicals, hypochlorite anions and superoxide anions by PMN were checked using fluorescent probes and chemiluminescence assays; a microbicidal activity assay against C. albicans was also performed. LLLT excited PMN to a higher functional profile, which was translated as superior production of reactive oxygen species (ROS) and increased fungicidal capacity. The most efficacious energy was 19.2 J and, interestingly, the 660 nm light was even more efficacious than 780 nm at increasing the respiratory burst of PMN and the fungicidal capacity. [ABSTRACT FROM AUTHOR]

We recently showed that it is possible to compromise tumor vessel function and, as a consequence, suppress growth of aggressive preclinical tumors by immunizing against the tumor vascular markers extra domain-A (ED-A) or -B (ED-B) of fibronectin, using a fusion protein consisting of the ED-A or ED-B peptide fused to bacterial thioredoxin. To address the mechanism behind fusion protein-induced immunization and the specific contribution of the different vaccine constituents to elicit an anti-self-antibody response, we immunized mice with modified or unmodified self-antigens, combined with different adjuvant components, and analyzed antibody responses by ELISA in sera. Several essential requirements to circumvent tolerance were identified: (1) a potent pattern recognition receptor agonist like an oligonucleotide containing unmethylated cytosine and guanine dinucleo-tides (CpG); (2) a depot adjuvant to keep the CpG at the site of injection; and (3) the presence of foreign sequences in the vaccine protein. Lack of either of these factors abolished the anti-self-response (P= 0.008). In mice genetically deficient for type IIFN signaling, there was a 60% reduction in the anti-self-response compared with wild-type (P= 0.011), demonstrating a key role of this pathway in CpG-induced circumvention of self-tolerance. Identification of these mechanistic requirements to generate a potent anti-self-immune response should significantly aid the design of efficient, specific, and safe therapeutic cancer vaccines. [ABSTRACT FROM AUTHOR]

Dopachrome tautomerase ( DCT) is involved in the formation of the photoprotective skin pigment eumelanin and has also been shown to have a role in response to apoptotic stimuli and oxidative stress. The effect of DCT on UVR DNA damage responses and survival pathways in human melanocytic cells was examined by knockdown experiments using melanoma cells, neonatal foreskin melanoblasts ( MB) in monoculture and in co-culture with human keratinocytes. MB cell strains genotyped as either MC1R WT or MC1R RHC homozygotes, which are known to be deficient in DCT, were transduced with lentivirus vectors for either DCT knockdown or overexpression. We found melanoma cell survival was reduced by DCT depletion and by UVR over time. UVR-induced p53 and pp53-Ser15 levels were reduced with DCT depletion. Knockdown of DCT in MC1R WT and MC1R RHC MB cells reduced their survival after UVR exposure, whereas increased DCT protein levels enhanced survival. DCT depletion reduced p53 and pp53-Ser15 levels in WM266-4 melanoma and MC1R WT MB cells, while MC1R RHC MB cells displayed variable levels. Both MC1R WT and RHC genotypes of MB cells were responsive to UVR at 3 h with increases in both p53 and pp53-Ser15 proteins. MC1R WT MB cell strains in coculture with keratinocytes have an increased cell survival after UVR exposure when compared to those in monoculture, a protective effect which appears to be conferred by the keratinocytes. [ABSTRACT FROM AUTHOR]

Abstract: The formation of new blood vessels (angiogenesis) is required for the growth of most tumors. The tumor microenvironment also induces lymphangiogenic factors that promote metastatic spread. Anti-angiogenic therapy targets the mechanisms behind the growth of the tumor vasculature. During the past two decades, several strategies targeting blood and lymphatic vessels in tumors have been developed. The blocking of vascular endothelial growth factor (VEGF)/VEGF receptor-2 (VEGFR-2) signaling has proven effective for inhibition of tumor angiogenesis and growth, and inhibitors of VEGF-C/VEGFR-3 involved in lymphangiogenesis have recently entered clinical trials. However, thus far anti-angiogenic treatments have been less effective in humans than predicted on the basis of pre-clinical tests in mice. Intrinsic and induced resistance against anti-angiogenesis occurs in patients, and thus far the clinical benefit of the treatments has been limited to modest improvements in overall survival in selected tumor types. Our current knowledge of tumor angiogenesis is based mainly on experiments performed in tumor-transplanted mice, and it has become evident that these models are not representative of human cancer. For an improved understanding, angiogenesis research needs models that better recapitulate the multistep tumorigenesis of human cancers, from the initial genetic insults in single cells to malignant progression in a proper tissue environment. To improve anti-angiogenic therapies in cancer patients, it is necessary to identify additional molecular targets important for tumor angiogenesis, and to get mechanistic insight into their interactions for eventual combinatorial targeting. The recent development of techniques for manipulating the mammalian genome in a precise and predictable manner has opened up new possibilities for the generation of more reliable models of human cancer that are essential for the testing of new therapeutic strategies. In addition, new imaging modalities that permit visualization of the entire mouse tumor vasculature down to the resolution of single capillaries have been developed in pre-clinical models and will likely benefit clinical imaging. [Copyright &y& Elsevier]

Because melanomas are intrinsically resistant to conventional radiotherapy and chemotherapy, many alternative treatment approaches have been developed such as biochemotherapy and immunotherapy. The most common cause of multidrug resistance (MDR) in human cancers is the expression and function of one or more TP- inding assette (ABC) transporters that efflux anticancer drugs from cells. Melanoma cells express a group of ABC transporters (such as ABCA9, ABCB1, ABCB5, ABCB8, ABCC1, ABCC2, and ABCD1) that may be associated with the resistance of melanoma cells to a broad range of anticancer drugs and/or of melanocytes to toxic melanin intermediates and metabolites. In this review, we propose a model (termed the ABC-M model) in which the intrinsic MDR of melanoma cells is at least in part because of the transporter systems that may also play a critical role in reducing the cytotoxicity of the melanogenic pathway in melanocytes. The ABC-M model suggests molecular strategies to reverse MDR function in the context of the melanogenic pathway, which could open therapeutic avenues towards the ultimate goal of circumventing clinical MDR in patients with melanoma. [ABSTRACT FROM AUTHOR]

Abstract: The value of identifying women with an inherited predisposition to epithelial ovarian cancer has become readily apparent with the identification of the BRCA1, and BRCA2 genes. Women who inherit a deleterious mutation in either of these genes have a very high lifetime risk of ovarian cancer (10–60%) and to some extent, increased risks of fallopian tube and peritoneal cancer. These highly lethal cancers are almost completely prevented by prophylactic salpingoophorectomy. BRCA1/2 mutation testing has become the accepted standard of care in families with a strong history of breast and/or ovarian cancer. This approach has the potential to reduce ovarian cancer mortality by about 10%. Although the ability to perform genetic testing for BRCA1 and 2 represents a significant clinical advance, the frequency of mutations in these high penetrance ovarian cancer susceptibility genes is low in most populations. There is evidence to suggest that ovarian cancer susceptibility might be affected by common low penetrance genetic polymorphisms like it was shown for several common disorders like diabetes or breast cancer. Although such polymorphisms would increase risk to a lesser degree, they could contribute to the development of a greater proportion of ovarian cancers by virtue of their higher frequencies in the population. It has been shown that the most powerful approach to studying low penetrance genes is an association study rather than a linkage study design. This review describes the efforts that have been made in this field by individual case–control studies and through multi-center collaborations as part of international consortia such as the Ovarian Cancer Association Consortium (OCAC). [Copyright &y& Elsevier]

GD3 ganglioside induces apoptosis in several cell types, but the molecular events through which this occurs are largely unknown. We investigated the apoptotic effects of GD3 expression using U-1242 MG glioblastoma cells, as these cells synthesize almost exclusively GM3 and GM2 but not GD3. To express GD3 under the control of the TetOn system with minimum leakage, we modified the system by constructing a single tri-cistronic retrovirus vector containing three genes separated by two internal ribosome entry sites: (a) transcriptional silencer, tTS; (b) mutant of reverse transcriptional activator, rtTA2(S)-M2 (provided by H. Bujard, Heidelberg, Germany); and (c) enhanced green fluorescent protein (EGFP), as an indicator of the tri-cistronic gene expression. Using flow cytometry, we selected glioma cells (U1242MG-GD3 clone) that express high levels of GD3 in response to doxycycline. Expression of GD3 was associated with apoptosis as verified by annexin-V binding, TdT-mediated dUTPnick end-labelling assay (TUNEL) , and EGFP degradation. GD3-induced apoptosis occurred via caspase-8 activation, as GD3 caused cleavage of caspase-8 and inhibition of caspase-8 activation by zlETD-fmk minimized GD3-induced apoptosis. [ABSTRACT FROM AUTHOR]

Wu C-S, Yu C-L, Wu C-S, Lan C-CE, Yu H-S. Narrow-band ultraviolet-B stimulates proliferation and migration of cultured melanocytes.Narrow-band ultraviolet-B (UVB) radiation is an effective treatment for vitiligo vulgaris. However, the mechanisms of narrow-band UVB in inducing repigmentation of vitiligo lesions are not thoroughly clarified. The purpose of our study was to investigate the effects of narrow-band UVB irradiation on melanocyte proliferation and migrationin vitro. Our results showed that the cell counts as well as[3H]thymidine uptake of melanocytes were significantly enhanced by narrow-band UVB-irradiated keratinocyte supernatants. In these supernatants, a significant increase in basic fibroblast growth factor (bFGF) and in endothelin-1 (ET-1) release was observed. bFGF is a natural mitogen for melanocytes, whereas ET-1 can stimulate DNA synthesis in melanocytes. This stimulatory effect of melanocyte proliferation by supernatants derived from narrow-band UVB-irradiated keratinocytes was significantly reduced by a selective endothelin-B (ET-B) receptor antagonist (BQ788), suggesting an essential role of ET-1 on melanocyte proliferation. Our results of time-lapse microphotography revealed a stimulatory effect of narrow-band UVB irradiation on melanocyte migration. Focal adhesion kinase (FAK) plays a pivotal role in cell migration. Phosphorylated FAK (p125FAK) expression on melanocyte was enhanced by narrow-band UVB irradiation. In this study, narrow-band UVB irradiation stimulated a significant increase in matrix metalloproteinase-2 (MMP-2) activity in melanocyte supernatants. Narrow-band UVB-irradiation-induced migration of melanocytes was significantly annihilated by the addition of p125FAK inhibitor (herbimycin-A) or MMP-2 inhibitor (GM6001). These results suggest that p125FAK and MMP-2 activity play important roles in narrow-band UVB-induced migration of melanocytes. Our results provide a theoretical basis for the effectiveness of narrow-band UVB irradiation in treating vitiligo. [ABSTRACT FROM AUTHOR]

Tau is a microtubule-associated protein whose transcript undergoes complex regulated splicing in the mammalian nervous system. In humans, exon 10 of the gene is an alternatively spliced cassette which is adult-specific and which codes for a microtubule binding domain. Mutations that affect splicing of exon 10 have been shown to cause inherited frontotemporal dementia (FTDP). In this study, we reconstituted naturally occurring exon 10 FTDP mutants and classified their effects on its splicing. We also carried out a comprehensive survey of the influence of splicing regulators on exon 10 inclusion and tentatively identified the site of action for several of these factors. Lastly, we identified the domains of regulators SWAP and hnRNPG, which are required for regulation of exon 10 splicing. [ABSTRACT FROM AUTHOR]

Tumour growth and metastasis involve the degradation of extracellular matrix components by matrix degrading enzymes produced by tumour cells and stromal fibroblasts. In this study, fibroblasts were obtained from biopsies on the border (TB) and 1 cm distant from the melanoma (TD) and cultured separately. Similar studies were performed with fibroblasts surrounding melanocytic nevi as control. The expression of matrix metalloproteinase-1 (MMP-1) mRNA and tissue matrix metalloproteinase inhibitor 1 (TIMP-1) were studied by Northern blot analysis. The activation antigen intercellular adhesion molecule-1 (ICAM-1) in TB- and TD-fibroblasts was investigated by flow cytometry. In melanoma, TB-fibroblasts showed an increased expression of MMP-1 mRNA mainly in fibroblasts obtained from tumours with extended invasive growth demonstrated by Clark level whereas the expression of the major specific inhibitor TIMP-1 was unaltered. In contrast, fibroblasts surrounding benign melanocytic nevi did not express elevated levels of MMP-1. The upregulation of MMP-1 in TB-fibroblasts compared to TD-fibroblasts was maintained during cultivation. Furthermore, MMP-1 mRNA expression and MMP-1 total protein amount in normal fibroblasts were increased by melanoma cell conditioned medium. We demonstrated an increased expression of ICAM-1 in TB-fibroblasts compared to TD-fibroblasts in vitro depending on the amount of inflammatory infiltrate in situ. The differences of ICAM expression disappeared during continued cell culture. These results support the idea that fibroblasts surrounding melanoma are activated and are possibly involved in the degradation of matrix proteins surrounding the tumour. [ABSTRACT FROM AUTHOR]

Abstract: Tau is a microtubule-associated protein whose transcript undergoes complex regulated splicing in the mammalian nervous system. Exon 10 of the gene is an alternatively spliced cassette that is adult-specific and that codes for a microtubule binding domain. Recently, mutations that affect splicing of exon 10 have been shown to cause inherited frontotemporal dementia (FTDP). In this study, we establish the endogenous expression patterns of exon 10 in human tissue; by reconstituting naturally occurring FTDP mutants in the homologous context of exon 10, we show that the cis determinants of exon 10 splicing regulation include an exonic silencer within the exon, its 5′ splice site, and the relative affinities of its flanking exons to it. By cotransfections in vivo, we demonstrate that several splicing regulators affect the ratio of tau isoforms by inhibiting exon 10 inclusion. [ABSTRACT FROM AUTHOR]

Recent investigations indicate that malignant melanoma cells can produce distinct cytokines While differences in the production of single cytokines have been observed among different melanoma cell lines, the extent of variability in the production of single and multiple cytokines between individual melanoma cell lines has not been as thoroughly investigated. A heterogeneity in melanoma cell cytokine production could have important implications for the biology of this aggressive neoplasm since certain cytokines may act as autocrine growth factors or be potent modulators of host immune response to the developing tumor. The purpose of this study is to assess the cytokine production profile of two widely available human melanoma cell lines, A375 and G361. The A375 cell line constitutively expressed the mRNA for IL-1&alfa;, IL-1β and PDGF-A, with increased expression of these cytokines after induction with PMA, GM-CSF mRNA was expressed by the A375 melanoma line only after induction with PMA. No IL-6 mRNA was detected in the A375 melanoma cell line. The cell culture supernatants from the A375 cells likewise contained a parallel increase in IL-1 activity as determined in the D10 bioassay and secreted GM-CSF and PDGF-AA as measured by ELISA. In contrast, the G361 cell line did not express IL-1, GM-CSF or PDGF-A mRNA (constitutively or after PMA induction) but expressed only IL-6 mRNA and secreted IL-6 activity after PMA induction. These results demonstrate a significant heterogeneity in the production of IL-1&alfa; IL-1β IL-6 GM-CSF, and PDGF in two distinct melanoma cell lines. This study demonstrates that individual melanoma cell lines express and secrete multiple cytokines both constitutively and after stimulation with PMA. The immunomodulating and mitogenic properties of these melanoma-derived cytokines may have implications in determining the biologic behavior of different malignant melanomas. [ABSTRACT FROM AUTHOR]

Presents a developmental biological study on the link between transcriptional and post-transcription process as they relate to the function of proteins. Description of proteins involved in both process; Methods and materials used in the study; Influence of promoters on post-transcriptional occurrences.

Reports on the short half-life of urokinase-type plasminogen activator (uPA) messenger RNA (mRNA) in LLC-PK cells. Finding the uPA mRNA is stable in breast cancer MDA-Mb-231 cells; Comparison of the stability of hybrid globin mRNA containing different parts of uPA mRNA in its 3' untranslated region; Cytoplasmic protein identified; Presence of regulatory sequences in the mRNA molecule responsible for its metabolism.

A co-culture system of melanocytic cells and keratinocytes was used to examine dendricity and dopachrome tautomerase (DCT) responses in low penetrant 'r' homozygote and 'R / +' heterozygote MC1R variant allele expressing cells compared to that of wild-type (WT) cells. The V60L-/- homozygote r variant cells showed similar responses to ligand as WT MC1R strains, while V92M-/- homozygote r variant cells were generally shown to have greater dendricity and express higher DCT than the WT cells, even at basal levels. The R151C+/ - heterozygote cells showed similar responses to WT cells, while the R160W+/- and D294H+/- variant cells were reduced in their responses to NDP-MSH, but still had an active cAMP response with forskolin treatment. These responses are consistent with the dominant negative effect of these alleles on the MC1R WT allele that has previously been demonstrated genetically and biochemically. [ABSTRACT FROM AUTHOR]