Ponencia
Parity-modulated systemic inflammatory profile and its impact on ovarian and oviductal gene expression in estropausal mice
Autor
Chacon, Carlos
Lizama, Luis
Sarmiento-Godoy, Sebastián
Ampuero, Sandra
Marcelain, Katherine
Asaki, E
Powell, JI
Urzua-Tobar, Ulises De La Cruz
Institución
Resumen
Background: Natural ageing courses with a low-grade chronic inflammation that increases susceptibility to various diseases including cancer. Given the known epidemiologic relationship between parity records and ovarian cancer risk, we report here circulating levels of pro/anti-inflammatory molecules in virgin and multiparous C57/BL6 female mice by estropausal age (14 months old). In addition, whole-genome transcriptional profiles of aged ovaries and oviducts revealed differential expression of inflammation and innate immune response related genes that might support a pre-neoplastic condition in both organs. Methods: Two groups of C57BL6 female mice were maintained in divergent reproductive conditions (virgin vs multiparous), until estropause. From 10 months-old, circulating pituitary hormones and cytokines (39 analytes total) were measured in serum monthly using a bead-based multiplex assay. By 15 months old, a subgroup of mice was euthanized and RNA extracted from ovary and oviduct pairs, and a second subgroup was injected with malignant, tumor-inducing MOSE cells. Gene expression profiling was performed with Illumina bead-array technology (Mouse Ref-8 expression v.2). Microarray data was extracted with GenomeStudio v2011.1, uploaded to NCI´s mAdb (https://madb.nci.nih.gov/), filtered and quantile normalized. Significant genes after limma statistics (p<0.05, log2fc ±0.5) were analyzed by Gene Ontology, KEGG and BioCarta.
Results: Circulating levels of Cxcl1 (GRO1/KC), Cxcl5 (LIX/ENA78), Ccl3 (MIP1a/SCYA3), Csf3 (g-CSF) and IL2 were significantly different between conditions. Intraperitoneal injection of syngeneic, tumor-inducing MOSE cells led to an increase of Ccl11 (Eotaxin-1), IL7, Ccl5 (RANTES) and Cxcl10 (IP10/SCYB10) in multiparous mice whereas IL5, and IL12b increased in virgin mice. IL6, IL10, Vegfa, Lif and Cxcl10 were increased in ascitic fluid respect to serum in both groups. Genome-wide gene expression analysis resulted in 245 and 97 differentially expressed genes (DEG) between conditions in ovaries and oviducts, respectively. Notably, 35% of oviductal DEG were implicated in inflammation/innate immunity-related processes. Transcription factors Stat1, Irf7, Hoxb5 and Spdef, calgranulins A and B (S100a8/9) and hemoglobins Hba-a1 and Hbb-bt were predominantly expressed in multiparous oviducts while Cxcl17, Spp1 (Osteopontin), Mmp7, Jak1 and Ddx3x expression predominated in virgin oviducts. Ovarian DEG involved in cytokine signaling included Tnfrsf12a, Tnfrsf21, Ifi205, Ccl9, Csf2rb2 and Il20rb predominantly expressed in virgin ovaries. Furthermore, growth-promoting, prosurvival kinases Sphk1, Sgk1, Chek1, Nuak2, Rps6ka2 and Mapkapk3 also showed predominant expression in this reproductive condition. Conclusion: Despite multiparity protects against ovarian cancer, differential cytokine levels at estropausal age suggests a higher extent of chronic inflammation in this condition. Except for IL5, IL10, IL1a and IL12b, most of the cytokines showed an increased trend in multiparity that persisted after intraperitoneal tumor induction. Though gene expression results suggested elevated proinflammatory signaling in multiparous organs, exclusive overexpression of antioxidant genes (S100a8, S100a9, Hba-a1 and Hbb-bt) in this condition would partially counteract such tumor susceptible feature, particularly in the oviduct. Increased expressions of tumor-cytokine Spp1 in oviducts and of lipid-kinase Sphk1 in ovaries of virgin animals might constitute key mediators of a preneoplastic state in this reproductive condition as suggested by epidemiological studies.