Causal pathways in lymphoid leukemia: the gut microbiota, immune cells, and serum metabolites.

Background: We employed Mendelian randomization (MR) to investigate the causal relationship between the gut microbiota and lymphoid leukemia, further exploring the causal relationships among immune cells, lymphoid leukemia, and potential metabolic mediators. Methods: We utilized data from the largest genome-wide association studies to date, encompassing 418 species of gut microbiota, 713 types of immune cells, and 1,400 serum metabolites as exposures. Summary statistics for lymphoid leukemia, acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL) were obtained from the FinnGen database. We performed bidirectional Mendelian analyses to explore the causal relationships among the gut microbiota, immune cells, serum metabolites, and lymphoid leukemia. Additionally, we conducted a two-step mediation analysis to identify potential intermediary metabolites between immune cells and lymphoid leukemia. Results: Several gut microbiota were found to have causal relationships with lymphoid leukemia, ALL, and CLL, particularly within the Firmicutes and Bacteroidetes phyla. In the two-step MR analysis, various steroid hormone metabolites (such as DHEAS, pregnenolone sulfateprogestogen derivatives, and androstenediol-related compounds) were identified as potential intermediary metabolites between lymphoid leukemia and immune cells. In ALL, the causal relationship between 1-palmitoyl-2-docosahexaenoyl-GPE (16:0/22:6) and ALL was mediated by CD62L-plasmacytoid DC%DC (mediated proportion=-2.84%, P=0.020). In CLL, the causal relationship between N6,n6,n6-trimethyllysine and CLL was mediated by HLA DR+ CD8br AC (mediated proportion=4.07%, P=0.021). Conclusion: This MR study provides evidence supporting specific causal relationships between the gut microbiota and lymphoid leukemia, as well as between certain immune cells and lymphoid leukemia with potential intermediary metabolites.

The association of appendectomy with prognosis and tumor-associated macrophages in patients with colorectal cancer.

The vermiform appendix plays an important role in colorectal immunity and the homeostasis of the gut microbiome. We aimed to evaluate the prognostic value of prior appendectomy for patients with colorectal cancer (CRC). This study revealed that prior appendectomy is an independent risk factor for the prognosis of patients with CRC, based on a multicentral CRC cohort. We further demonstrated that appendectomy induced a poor prognosis of CRC through the depletion of M1 macrophage cells in AOM-induced mice, which was confirmed in age-, sex-, and location-matched patients' cohorts and orthotopic model models with the CT26 cell line. Poor responses to anti-PD-1 immunotherapy were detected in patients with CRC with appendectomy, and cetuximab is an effective treatment for patients with appendectomy-associated colorectal cancer (APD-CRC) to improve their prognosis. Our study will provide a reference for developing treatment plans for a considerable number of patients with APD-CRC, which is of great clinical significance.

Mendelian randomization analysis reveals the combined effects of epigenetics and telomere biology in hematologic cancers.

BACKGROUND: Telomere shortening and epigenetic modifications are key factors in aging and hematologic diseases. This study investigates the relationship of telomere length and epigenetic age acceleration (EAA) with hematologic cancers, blood cells, and biochemical markers through the epigenetic clocks. METHODS: This study primarily utilizes genome-wide association studies of populations of European descent as instrumental variables, exploring the causal relationships between exposures and outcomes through a bidirectional two-sample Mendelian randomization (MR) approach. MR techniques include inverse variance weighted (IVW), MR Egger, and weighted median modes. Heterogeneity and pleiotropy in MR are assessed using Cochran's Q test and the MR Egger intercept, with the robustness of the conclusions further validated by multivariable MR (MVMR). RESULTS: Our research shows that longer telomere lengths significantly increase the risk of multiple myeloma, leukemia, and lymphoma (OR > 1, P < 0.05) and establish a causal relationship between telomere length and red blood cell indices such as RBC (OR = 1.121, PIVW = 0.034), MCH (OR = 0.801, PIVW = 2.046e-06), MCV (OR = 0.801, PIVW = 0.001), and MCHC (OR = 0.813, PIVW = 0.002). Additionally, MVMR analysis revealed an association between DNA methylation PhenoAge acceleration and alkaline phosphatase (OR = 1.026, PIVW = 0.007). CONCLUSION: The study clarifies the relationships between telomere length, EAA, and hematological malignancies, further emphasizing the prognostic significance of telomere length and EAA. This deepens our understanding of the pathogenesis of hematological diseases, which can inform risk assessment and therapeutic strategies.

Dynamic m6A mRNA methylation reveals the involvement of AcALKBH10 in ripening-related quality regulation in kiwifruit.

Kiwifruit ripening is a complex and highly coordinated process that occurs in conjunction with the formation of fruit edible quality. The significance of epigenetic changes, particularly the impact of N6-methyladenosine (m6A) RNA modification on fruit ripening and quality formation, has been largely overlooked. We monitored m6A levels and gene expression changes in kiwifruit at four different stages using LC-MS/MS, MeRIP, RNA-seq, and validated the function of AcALKBH10 through heterologous transgenic expression in tomato. Notable m6A modifications occurred predominantly at the stop codons and the 3' UTRs and exhibited a gradual reduction in m6A levels during the fruit ripening process. Moreover, these m6A modifications in the aforementioned sites demonstrated a discernible inverse relationship with the levels of mRNA abundance throughout the ripening process, suggesting a repression effect of m6A modification in the modulation of kiwifruit ripening. We further demonstrated that AcALKBH10 rather than AcECT9 predominantly regulates m6A levels in ripening-related genes, thereby exerting the regulatory control over the ripening process and the accumulation of soluble sugars and organic acids, ultimately influencing fruit ripening and quality formation. In conclusion, our findings illuminate the epi-regulatory mechanism involving m6A in kiwifruit ripening, offering a fresh perspective for cultivating high-quality kiwifruit with enhanced nutritional attributes.

MT1E in AML: A Gateway to Understanding Regulatory Cell Death and Immunotherapeutic Responses.

Regulated cell death (RCD) plays a crucial role in the initiation and progression of tumors, particularly in acute myeloid leukemia (AML). This study investigates the prognostic importance of RCD-related genes in AML and their correlation with immune infiltration.We combined TCGA and GTEx data, analyzing 1488 RCD-related genes, to develop a predictive model using LASSO regression and survival analysis. The model's accuracy was validated against multiple databases, examining immune cell infiltration, therapy responses, and drug sensitivity among risk groups. RT-qPCR confirmed MT1E expression in AML patients and healthy bone marrow. CCK8 and Transwell assays measured cell proliferation, adhesion, migration, and invasion, while flow cytometry and Western blotting assessed apoptosis and protein expression.We developed a prognostic model using 10 RCD methods, which demonstrated strong predictive ability, showing an inverse correlation between age and risk scores with survival in AML patients. Functional enrichment analysis of the model is linked to immune modulation pathways. RT-qPCR revealed significantly lower MT1E expression in AML versus healthy bone marrow (p<0.05). Consequently, experiments were designed to assess the function of MT1E overexpression.Findings indicated that MT1E overexpression showed it significantly reduced THP-1 cell proliferation and adhesion(p<0.001), decreased migration(p<0.001) and invasiveness(p<0.05), and increased apoptosis(p<0.05), with a notable rise in Caspase3 expression.A novel AML RCD risk model was developed, showing promise as a prognostic marker for evaluating outcomes and immune therapy effectiveness. Insights into MT1E's impact on AML cell proliferation and apoptosis open possibilities for improving patient outcomes and devising personalized treatment strategies.

Effect of high-fat diet on cerebral pathological changes of cerebral small vessel disease in SHR/SP rats.

Cerebral small vessel diseases (CSVD) are neurological disorders associated with microvessels, manifested pathologically as white matter (WM) changes and cortical microbleeds, with hypertension as a risk factor. Additionally, a high-fat diet (HFD) can affect peripheral vessel health. Our study explored how HFD affects cerebral small vessels in normotensive WKY, hypertensive SHR, and SHR/SP rats. The MRI results revealed that HFD specifically increased WM hyperintensity in SHR/SP rats. Pathologically, it increased WM pallor and vacuolation in SHR and SHR/SP rats. Levels of blood-brain barrier (BBB) protein claudin 5 were decreased in SHR and SHR/SP compared to WKY, with HFD having minimal impact on these levels. Conversely, collagen IV levels remained consistent among the rat strains, which were increased by HFD. Consequently, HFD caused vessel leakage in all rat strains, particularly within the corpus callosum of SHR/SP rats. To understand the underlying mechanisms, we assessed the levels of hypoxia-inducible factor-1α (HIF-1α), Gp91-phox, and neuroinflammatory markers astrocytes, and microglia were increased in SHR and SHR/SP compared to WKY and were further elevated by HFD in all rat strains. Gp91-phox was also increased in SHR and SHR/SP compared to WKY, with HFD causing an increase in WKY but little effect in SHR and SHR/SP. In conclusion, our study demonstrates that HFD, in combined with hypertension, intensifies cerebral pathological alterations in CSVD rats. This exacerbation involves increased oxidative stress and HIF-1α in cerebral vessels, triggering neuroinflammation, vascular basement membrane remodeling, IgG leakage, and ultimately WM damage.

Oceanospirillum sediminis sp. nov., Isolated From Coastal Sediment in the Yellow Sea.

A novel Gram-negative, motile, aerobic, spiral-shaped bacterium designated D5T, was isolated from a coastal sediment collected in the Yellow Sea. Optimal growth occurred at 30 °C, pH 7.0-8.0 and in the presence of 1-3% (w/v) NaCl. Strain D5T contained ubiquinone 8 (Q-8) as the predominant respiratory quinone. The major fatty acids (> 10%) were C16:0, C16:1 ω7c/C16:1 ω6c and C18:1w7c/C18:1w6c. The main polar lipids were phosphatidylglycerol and phosphatidylethanolamine. The draft genome is 5.6 Mb in length, and DNA G + C content is 47.2 mol%. 16S rRNA gene sequences showed that strain D5T is most closely related to Oceanospirillum beijerinckii NBRC 15445T (97.8%, sequence similarity). However, the digital DNA-DNA hybridization (dDDH) value and average nucleotide identity (ANI) between strain D5T and O. beijerinckii is only 27.8% and 77.1%. Phylogenetic trees based on 16S rRNA gene sequences and whole genomes all indicated that strain D5T formed a separate branch in the genus Oceanospirillum. Combined results of the polyphasic analyses suggested that strain D5T represents a novel species in the genus Oceanospirillum, for which the name Oceanospirillum sediminis sp. nov. is proposed. The type strain is D5T (= MCCC 1K06061T = KCTC 62987T).

Association Between Types of Posterior Staphyloma and Refractive Error After Cataract Surgery for High Myopia.

Purpose: To investigate the association between different types of posterior staphyloma (PS) and refractive error (RE) after cataract surgery in patients with high myopia. Methods: This retrospective study included 113 eyes of 113 highly myopic patients with PS. PS was detected using a wide-field fundus imaging system. PS was classified into wide macular, narrow macular, and other types. RE equaled the actual spherical equivalent (SE) minus the targeted SE values 3 months after cataract surgery. Results: The rates of wide macular, narrow macular, and other types of PS were 46.02, 39.82, and 14.16%, respectively. There were no significant differences in best corrected distance visual acuity (BCDVA) or SE among the three classifications of PS before cataract surgery (P > 0.05). However, postoperative BCDVA and SE were significantly different among the three types of PS patients (P < 0.05). The average RE values were 0.98 ± 1.00 D, 0.19 ± 0.87 D, 0.13 ± 0.59 D, respectively; the statistical differences of RE were <0.01, <0.01, and 0.81 (wide macular vs. narrow macular, wide macular vs. other types, narrow macular vs. other types), respectively. Multivariate linear regression analysis revealed that higher hyperopia RE after surgery was associated with wide macular staphyloma (P < 0.001), more myopic SE (P = 0.003), and increased BCDVA (P = 0.002) before surgery. Conclusions: Wide macular PS may be associated with more hyperopic RE; it may serve as a critical biomarker of hyperopic RE after cataract surgery in highly myopic patients.

Ethylene response factor AcERF91 affects ascorbate metabolism via regulation of GDP-galactose phosphorylase encoding gene (AcGGP3) in kiwifruit.

Kiwifruit is known as 'the king of vitamin C' because of the high content of ascorbic acid (AsA) in the fruit. Deciphering the regulatory network and identification of the key regulators mediating AsA biosynthesis is vital for fruit nutrition and quality improvement. To date, however, the key transcription factors regulating AsA metabolism during kiwifruit developmental and ripening processes remains largely unknown. Here, we generated a putative transcriptional regulatory network mediating ascorbate metabolism by transcriptome co-expression analysis. Further studies identified an ethylene response factor AcERF91 from this regulatory network, which is highly co-expressed with a GDP-galactose phosphorylase encoding gene (AcGGP3) during fruit developmental and ripening processes. Through dual-luciferase reporter and yeast one-hybrid assays, it was shown that AcERF91 is able to bind and directly activate the activity of the AcGGP3 promoter. Furthermore, transient expression of AcERF91 in kiwifruit fruits resulted in a significant increase in AsA content and AcGGP3 transcript level, indicating a positive role of AcERF91 in controlling AsA accumulation via regulation of the expression of AcGGP3. Overall, our results provide a new insight into the regulation of AsA metabolism in kiwifruit.

Neuroprotective effects of verbascoside against Alzheimer's disease via the relief of endoplasmic reticulum stress in Aß-exposed U251 cells and APP/PS1 mice.

BACKGROUND: Endoplasmic reticulum (ER) stress is involved in the progression of Alzheimer's disease (AD). Verbascoside (VB), an active phenylethanoid glycoside that was first isolated from Verbascum sinuatum (the wavyleaf mullein), possesses anti-inflammatory, antioxidative, and anti-apoptotic effects. The purpose of this study was to elucidate the beneficial effects of VB in amyloid ß (Aß)1-42-damaged human glioma (U251) cells and in APPswe/PSEN1dE9 transgenic (APP/PS1) mice. METHODS: U251 cells were co-incubated with 10 µM of Aß1-42 and treated with VB. The protective effects of VB were investigated by using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide assay, flow cytometry, fluorescence staining, and transmission electron microscopy. APP/PS1 transgenic mice were treated for 6 weeks with VB. Learning and memory were evaluated using a Morris water maze test. Immunohistochemistry, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling, thioflavin-S staining, and proteomics analysis were performed to study the potential neuroprotective mechanism. Enzyme-linked immunosorbent assays and western blot were performed to analyze altered protein levels of brain lysates in APP/PS1 mice and/or Aß1-42-damaged U251 cells. RESULTS: In Aß1-42-damaged U251 cells, VB significantly improved cell viability, inhibited apoptosis, reduced calcium accumulation and the intracellular concentrations of reactive oxygen species, and improved the morphology of mitochondria and ER. In APP/PS1 mice, 6-week administration of VB significantly improved memory and cognition. VB inhibited apoptosis, reduced the deposition of Aß, reduced the formation of neurofibrillary tangles formed by hyperphosphorylated tau protein, and downregulated the expression levels of 4-hydroxynonenal and mesencephalic astrocyte-derived neurotrophic factor in the brains of APP/PS1 mice. Proteomics analysis of mouse hippocampus suggested that the neuroprotective effect of VB may be related to the reduction of ER stress. This was indicated by the fact that VB inhibited the three branches of the unfolded protein response, thereby attenuating ER stress and preventing apoptosis. CONCLUSIONS: The results confirmed that VB possesses significant neuroprotective effects, which are related to the reduction of ER stress. These findings support the status of VB as a potentially effective treatment for AD and warrant further research.

Antibacterial effects of a polypeptide-enriched extract of Rana chensinensis via the regulation of energy metabolism.

The improper usage of antibiotics is known to cause widespread antibiotic resistance. In this study, the antibacterial effects of a polypeptide-enriched extract from the skin of the amphibian Rana chensinensis (RCP) were evaluated against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacterium Staphylococcus aureus and the fungus Candida albicans. The mechanisms underlying these effects were also studied, and the minimum inhibitory concentration of RCP was determined for each species. Analyses of the levels of adenosine triphosphates (ATPases), including Na+/K+-ATPase and Ca2+-ATPase, and scanning electron microscopy confirmed that RCP damaged the microbial cell walls and membranes. RCP perturbed microbial metabolism and particularly affected the tricarboxylic acid cycle (TCA), suggesting that this agent downregulated the levels of succinate dehydrogenase, malate dehydrogenase and ATPase activity in cells. Furthermore, RCP caused the leakage of genetic material from all four microbial strains. In conclusion, RCP effectively inhibited the growth of Gram-negative and Gram-positive bacteria and a fungal species by disrupting energy metabolic processes.

Possible mechanisms of the antimicrobial effects of polypeptide­enriched Gastrodia elata Blume extracts.

The present study aimed to evaluate the antimicrobial activity and the possible mechanisms of activity of polypeptide­enriched Gastrodia elata extracts (GEP) against the gram­negative bacteria Escherichia coli and Pseudomonas aeruginosa, the gram­positive bacterium Staphylococcus aureus and the fungus Candida albicans. The antimicrobial activity of GEP was first confirmed by determining the minimum inhibitory concentration by growth curve analysis. GEP was found to damage the cell wall and membrane of the microorganisms tested, as revealed by the morphological changes visible through scanning electron microscopy, and by the observed leakage of alkaline phosphatase and ß­galactosidase from cells. GEP was demonstrated to perturb the metabolism of the microorganisms, especially the tricarboxylic acid cycle, as indicated by the reduced intracellular activity of succinate dehydrogenase, malate dehydrogenase and ATPases, including the Na+/K+­ATPase and the Ca2+­ATPase. In addition, GEP caused the leakage of the genetic material of the bacteria and the fungus, as indicated by the increased OD260. The results of the present study indicated that GEP may exert its antimicrobial activity by damaging cell walls and membranes, causing the leakage of genetic material, and by perturbing cellular metabolism.

Construction of DOX/APC co-loaded BiOI@CuS NPs for safe and highly effective CT imaging and chemo-photothermal therapy of lung cancer.

Recently, a variety of nanoparticles have been widely used as imaging agents or carriers for the diagnosis and therapy of lung cancer. However, their poor imaging effect, high toxicity, pro-inflammatory effect and ineffective treatment are still a great challenge. In this work, we reported a novel kind of BiOI@CuS nanoparticle to achieve safe and effective therapy of lung cancer by co-loading hydrochloric acid doxorubicin (DOX) and aspirin phenacetin and caffeine (APC). The nanoparticles can effectively relieve inflammatory reactions induced by photo-thermal therapy (PTT). In vitro and in vivo assays showed that DOX/APC co-loaded BiOI@CuS exhibited an effective chemo-photothermal comprehensive therapy effect and good CT imaging capability. Consequently, this multifunctional nanosystem provides a versatile and promising platform in the imaging and treatment of lung cancer in further applications.

Candida albicans vaginitis in a murine model is reduced by polypeptide-enriched Gastrodia elata extracts.

Aim: The primary objective of this study was to evaluate the effects of polypeptide-enriched Gastrodia elata extracts (GE) on vulvovaginal candidiasis (VVC). Materials & methods: A VVC model induced by Candida albicans (C. albicans) infection was successfully developed in BALB/c mice. After treatment, the colony-forming unit (CFU) of vaginal lavage was measured by plating. The extent of the inflammatory response was assessed by hematoxylin-eosin (H&E) staining and enzyme-linked immunosorbent assay (ELISA). Results: GE had an inhibitory effect on the proliferation of C. albicans and inflammatory reaction. Meanwhile, it had a potentially beneficial effect on the growth of Lactobacillus. Conclusion: These results showed the potential application of GE as an antifungal agent in VVC treatment.

A versatile theranostic nanoplatform based on mesoporous silica.

A versatile of mesoporous silica is designed and operated, including ion doping, surface modify and pore adsorption, based on aqueous well-dispersed. Thus, a multifunctional theranostic nanoplatform is obtained through endowing some functional materials. Detailedly, Gd ions is introduced to mesoporous silica (GM nanoparticles) via a co-assemble process, which is used as prime carrier with MRI. Furthermore, the surface graft of hyaluronic acid (HA) molecule makes contribution to lymph system-targeted delivery (GMH nanoparticles). Additionally, the introduction of functional molecules including Iopamidol (IGMH nanoparticles) and DOX (DGMH nanoparticles) could combine the diagnosis and therapy with CT and sustained drug release. We present evidence that the IGMH and DGMH nanoparticles are highly targeted to lymph system in vitro and in vivo, and highlight CT and MR imaging of IGMH nanoparticles in lymph system, and chemotherapy and MR imaging of DGMH nanoparticles in lymph cancer. Our results provide a new universal manufacture for mesoporous silica to obtain a multifunctional theranostic nanoplatform, has great potential for use in biological applications.

Overexpression of Collapsin Response Mediator Protein 1 Inhibits Human Trophoblast Cells Proliferation, Migration, and Invasion.

Collapsin response mediator protein 1 (CRMP-1) is widely expressed in the nervous system and has tumor suppressive effects. Our previous studies have demonstrated that CRMP-1 was expressed in the trophoblasts of the whole stage of pregnancy with significantly increasing expression in the placenta of early-onset preeclampsia. Preeclampsia, especially early onset, is strongly associated with the dysfunction of trophoblast including proliferation, apoptosis, migration, and invasion. In this study, we found an inhibitory effect of CRMP-1 on proliferation, migration, invasion, and an enhanced effect on apoptosis in human trophoblast cell lines HTR-8/SVneo and JEG-3 by MTT assay, colony formation assay, cell viability assay, caspase 3/7 activity assay, scratch wound assay, and Matrigel Transwell assay. Overexpression of CRMP-1 in trophoblast cells led to downregulate expression of matrix metalloproteinase 2 and 9. The expression of CRMP-1 was detected by real-time quantitative polymerase chain reaction and Western blot analysis. Thus, we suggested that CRMP-1 might have implications for the pathogenesis of preeclampsia by regulating the biological behavior of trophoblast cells.

Massive expansion and differential evolution of small heat shock proteins with wheat (Triticum aestivum L.) polyploidization.

Wheat (Triticum aestivum), one of the world's most important crops, is facing unprecedented challenges due to global warming. To evaluate the gene resources for heat adaptation in hexaploid wheat, small heat shock proteins (sHSPs), the key plant heat protection genes, were comprehensively analysed in wheat and related species. We found that the sHSPs of hexaploid wheat were massively expanded in A and B subgenomes with intrachromosomal duplications during polyploidization. These expanded sHSPs were under similar purifying selection and kept the expressional patterns with the original copies. Generally, a strong purifying selection acted on the α-crystallin domain (ACD) and theoretically constrain conserved function. Meanwhile, weaker purifying selection and strong positive selection acted on the N-terminal region, which conferred sHSP flexibility, allowing adjustments to a wider range of substrates in response to genomic and environmental changes. Notably, in CI, CV, ER, MI and MII subfamilies, gene duplications, expression variations and functional divergence occurred before wheat polyploidization. Our results indicate the massive expansion of active sHSPs in hexaploid wheat may also provide more raw materials for evolving functional novelties and generating genetic diversity to face future global climate changes, and highlight the expansion of stress response genes with wheat polyploidization.

Roles of Rap1 signaling in tumor cell migration and invasion.

Ras-associated protein-1 (Rap1), a small GTPase in the Ras-related protein family, is an important regulator of basic cellular functions (e.g., formation and control of cell adhesions and junctions), cellular migration, and polarization. Through its interaction with other proteins, Rap1 plays many roles during cell invasion and metastasis in different cancers. The basic function of Rap1 is straightforward; it acts as a switch during cellular signaling transduction and regulated by its binding to either guanosine triphosphate (GTP) or guanosine diphosphate (GDP). However, its remarkably diverse function is rendered by its interplay with a large number of distinct Rap guanine nucleotide exchange factors and Rap GTPase activating proteins. This review summarizes the mechanisms by which Rap1 signaling can regulate cell invasion and metastasis, focusing on its roles in integrin and cadherin regulation, Rho GTPase control, and matrix metalloproteinase expression.

KiSS­1­mediated suppression of the invasive ability of human pancreatic carcinoma cells is not dependent on the level of KiSS­1 receptor GPR54.

The onset of local invasion and lymphatic metastasis in pancreatic cancer limits survival following surgical intervention and additional therapies. Reduced expression of KiSS­1 in pancreatic cancer is associated with cancer metastasis. Previous studies have indicated that kisspeptin, the KiSS­1 peptide, is able to bind to its receptor­GPR54 (hOT7T175) and suppress the migration of PANC­1 pancreatic cancer cells. Whether the metastatic suppression of KiSS­1 is dependent on the levels of GPR54 in pancreatic cancer cell lines remains unclear. Human BxPC­3 pancreatic carcinoma cells are highly differentiated without exhibiting metastasis, however PANC­1 pancreatic carcinoma cells are poorly differentiated and exhibit local and lymph node metastasis. Compared with primary cultured trophoblasts, BxPc­3 and PANC­1 cells were observed to express low levels of KiSS­1 mRNA and protein, measured using reverse transcription­quantitative polymerase chain reaction and western blotting, respectively. However, greater mRNA and protein expression levels of GPR54 were observed in PANC­1 cells compared with BxPc­3 cells. An MTT assay was used to investigate the effect of KiSS­1 on BxPc­3 and PANC­1 cell proliferation. There were no significant differences in proliferation following transfection with KiSS­1 in BxPc­3 and PANC­1 cells compared with the controls (P>0.05). A Transwell assay with chambers coated with Matrigel was used to evaluate the in vitro invasive ability of BxPc­3 and PANC­1 cells, with the invasion index of BxPc­3 and PANC­1 cells significantly reduced following 48 h of KiSS­1 overexpression (P<0.05). The mRNA and protein expression levels of KiSS­1 were significantly increased in BxPc­3 and PANC­1 cells 48 h subsequent to transfection with KiSS­1 (P<0.05), while GPR54 expression was not altered (P>0.05). KiSS­1 is a metastasis suppressor gene of pancreatic cancer, and this suppression is not dependent on the expression levels of GPR54. Therefore, KiSS­1 is potentially a novel target for gene therapy.

Dietary fiber intake and pancreatic cancer risk: a meta-analysis of epidemiologic studies.

Evidence on the association between dietary fiber intake and pancreatic cancer risk has been controversial. Therefore, we carried out this meta-analysis to summarize available evidence from epidemiologic studies on this point. Relevant studies were identified by searching PubMed, Embase and Web of Science databases as well as by reviewing the rence lists of relevant articles. Random or fixed-effects model was used to calculate the summary risk estimates and 95% confidence intervals (CIs). This meta-analysis included one cohort and thirteen case-control studies which involving a total of 3287 subjects with pancreatic cancer. After summarizing the risk estimates of these studies, we yielded a significant association between dietary fiber intake and pancreatic cancer risk among case-control studies (odds ratio = 0.54; 95%CI = 0.44-0.67; I(2) = 41.4%; P = 0.043) but a non-significant result in cohort study (hazard ratio = 1.01; 95%CI = 0.59-1.74). Additionally, significant inverse associations were observed when we carried out the stratify analyses by the study characteristics and adjustment for potential confounders among case-control studies. Given only one cohort study included in the present meta-analysis, further prospective-designed studies should validate our findings and report more detail results, including those for subtypes of fiber, the risk estimates which corrected the impact of measurement errors and fully adjust for the potential confounders.