MiR‐222 inhibits apoptosis in porcine follicular granulosa cells by targeting the THBS1 gene

Apoptosis of granulosa cells affects follicular atresia and reproduction and is regulated by miRNAs and the expression of certain genes. For the present study, we investigated the regulatory relationship between microRNA‐222 (miR‐222) and THBS1 in porcine follicular granulosa cells (pGCs) and its effects on apoptosis to provide empirical data for developing methods to improve pig fecundity. Results revealed that miR‐222 promotes the proliferation of pGCs. MiRNA mimics and luciferase reporter assays revealed that miR‐222 functions as an anti‐apoptotic factor in pGCs. MiR‐222 mimics in pGCs result in the upregulation of the anti‐apoptotic BCL‐2 gene, down‐regulation of the proapoptotic caspase‐3 gene, and inhibition of apoptosis. MiR‐222 inhibitors reduced BCL‐2 and had no significant effect on caspase‐3. MiR‐222 mimics promoted estrogen levels. Inhibition of THBS1 inhibited pGC apoptosis. Transfection of THBS1‐siRNA reduced the proapoptotic BAX gene. MiR‐222 can directly target the 3′‐untranslated region of the THBS1 gene. MiR‐222 mimics suppressed THBS1 mRNA and proteins, but these were upregulated by the miR‐222 inhibitor. Transfection of THBS1‐siRNA resulted in the inhibition of the miR‐222 inhibitor, which suggests that miR‐222 inhibits pGC apoptosis by targeting THBS1. These findings suggest that miR‐222 and THBS1 play important roles in follicular atresia, ovarian development, and female reproduction.     

Immunohistochemical expression of MDR1‐Pgp 170 in canine cutaneous and oral melanomas: pattern of expression and association with tumour location and phenotype

Canine melanoma (CMM) more commonly affects the oral mucosa and the cutis. CMM shares several features with human melanomas (HMM), included resistance to a broad variety of antineoplastic chemotherapy agents. P‐glycoprotein 1 (Pgp) expression is a well‐recognized feature of multi‐drug resistance and the purpose of this study was to investigate its expression in treatment naïve CMM. We also investigated Pgp association with tumour location and histological features. Histology records of CMM were retrieved, including patients from 2012–2014. Twenty‐five cases of CMM were included in this study. Results revealed that Pgp is expressed in CMM and oral tumours were more likely to have a membranous Pgp expression (100%) than cutaneous tumours (66.6%) (P = 0.010). Cytoplasmic and nuclear Pgp expression could also be identified. Results of this study bring useful data that help in understanding one of the possible mechanisms responsible of intrinsic chemotherapy resistance in canine CMM.     

m‐carboxycinnamic acid bishydroxamide improves developmental competence,reduces apoptosis and alters epigenetic status and gene expression pattern in cloned buffalo (Bubalus bubalis) embryos

Incomplete or aberrant reprogramming of nuclear genome is one of the major problems in somatic cell nuclear transfer. In this study, we studied the effect of histone deacetylase inhibitor m‐carboxycinnamic acid bishydroxamide (CBHA) on in vitro development of buffalo embryos produced by Hand‐made cloning. Cloned embryos were treated with CBHA (0, 5, 10, 20 or 50 μM) for 10 hr from the start of reconstruction till activation. At 10 μM, but not at other concentrations examined, CBHA increased (p < .05) the blastocyst rate (63.77 ± 3.97% vs 48.63 ± 3.55%) and reduced (p < .05) the apoptotic index of the cloned blastocysts (8.91 ± 1.94 vs 4.36 ± 1.08) compared to untreated controls, to levels similar to those in IVF blastocysts (4.78 ± 0.74). CBHA treatment, at all the concentrations examined, increased (p < .05) the global level of H3K9ac in cloned blastocysts than in untreated controls to that observed in IVF blastocysts. Treatment with CBHA (10 μM) decreased (p < .05) the global level of H3K27me3 in cloned blastocysts than in untreated controls but it was still higher (p < .05) than in IVF blastocysts. CBHA (10 μM) treatment increased (p < .05) the relative expression level of pluripotency‐related genes OCT‐4 and NANOG, and anti‐apoptotic gene BCL‐XL, and decreased (p < .05) that of pro‐apoptotic gene BAX than in untreated controls but did not affect the relative expression level of apoptosis‐related genes p53 and CASPASE3 and epigenetics‐related genes DNMT1, DNMT3a and HDAC1. These results suggest that treatment of cloned embryos with 10 μM CBHA improves the blastocyst rate, reduces the level of apoptosis and alters the epigenetic status and gene expression pattern.