Celia Devenish

The alternative lengthening of telomeres pathway may operate in non-neoplastic human cells†

The alternative lengthening of telomeres (ALT) mechanism represents an alternative to the enzyme telomerase in the maintenance of mammalian telomeres in 25–60% of sarcomas and a minority of carcinomas (about 5–15%). ALT‐positive cells are distinguished by long and heterogeneous telomere length distributions by terminal restriction fragment (TRF) Southern blotting. Another diagnostic marker of ALT is discrete nuclear co‐localized signals of telomeric DNA and the promyelocytic leukaemia protein (PML), referred to as ALT‐associated PML bodies (APBs). Recently, we detected smaller sized co‐localized PML and telomere DNA (APB‐like) bodies in endothelial cells adjacent to astrocytoma tumour cells in situ. In this study, we examined a wide variety of non‐neoplastic tissues, and report that co‐localized signals of PML and telomere DNA are present in endothelial, stromal, and some epithelial cells. Co‐localized signals of PML and telomere DNA showed an increased frequency in non‐neoplastic cells with DNA damage. These results suggest that a mechanism similar to that in ALT‐positive tumours also operates in non‐neoplastic cells, which may be activated by DNA damage. Copyright

A clinicopathological study of episomal papillomavirus infection of the human placenta and pregnancy complications.

Viral infections are known to adversely affect pregnancy, but scant attention has been given to human papilloma virus (HPV) infection. We aimed to determine the molecular and histopathological features of placental HPV infection, in association with pregnancy complications including fetal growth restriction, pre-maturity, pre-eclampsia, and diabetes. Three hundred and thirty-nine placentae were selected based on the presence or absence of pregnancy complications. Five independent methods were used to identify HPV in the placenta, namely, immunohistochemistry for L1 viral capsid, in situ hybridization to high-risk HPV DNA, PCR, western blotting, and transmission electron microscopy. Pregnancy complications and uterine cervical smear screening results were correlated with placental HPV histopathology. In this study, which was deliberately biased towards complications, HPV was found in the decidua of 75% of placentae (253/339) and was statistically associated with histological acute chorioamnionitis (P<0.05). In 14% (35/253) of the HPV positive cases, HPV L1 immunoreactivity also occurred in the villous trophoblast where it was associated with a lymphohistiocytic villitis (HPV-LHV), and was exclusively of high-risk HPV type. HPV-LHV significantly associated with fetal growth restriction, preterm delivery, and pre-eclampsia (all P<0.05). All cases of pre-eclampsia (20/20) in our cohort had high-risk placental HPV. A further 55 cases (22%, 55/253) of HPV positive placentae had minimal villous trophoblast HPV L1 immunoreactivity, but a sclerosing pauci-immune villitis, statistically associated with diabetes (49.1%, 27/55, P<0.05). For women with placental HPV, 33% (69/207) had an HPV-related positive smear result before pregnancy compared with (9.4% 8/85) of women with HPV-negative placentae (P=0.0001). Our findings support further investigations to determine if vaccination of women and men will improve pregnancy outcomes.

A preliminary survey of Atopobium vaginae in women attending the Dunedin gynaecology out-patients clinic: Is the contribution of the hard-to-culture microbiota overlooked in gynaecological disorders?

Preliminary studies have indicated that the recently described bacterium Atopobium vaginae may have an association with bacterial vaginosis (BV). Fifty‐five women attending the gynaecology out‐patients clinic were tested for the presence of this micro‐organism, Gardnerella vaginalis, Mobiluncus and Bacteroides species by polymerase chain reaction (PCR)‐based assays. The frequency of detection was 40%. PCR detection of Gardnerella vaginalis with A. vaginae, occurred in 50% of A. vaginae‐positive cases. Due to the high detection rate of A. vaginae we believe that it is important to determine whether this and other hard‐to‐culture microorganisms have a role in gynaecological disorders.

Placental Hypomethylation Is More Pronounced in Genomic Loci Devoid of Retroelements

The human placenta is hypomethylated compared to somatic tissues. However, the degree and specificity of placental hypomethylation across the genome is unclear. We assessed genome-wide methylation of the human placenta and compared it to that of the neutrophil, a representative homogeneous somatic cell. We observed global hypomethylation in placenta (relative reduction of 22%) compared to neutrophils. Placental hypomethylation was pronounced in intergenic regions and gene bodies, while the unmethylated state of the promoter remained conserved in both tissues. For every class of repeat elements, the placenta showed lower methylation but the degree of hypomethylation differed substantially between these classes. However, some retroelements, especially the evolutionarily younger Alu elements, retained high levels of placental methylation. Surprisingly, nonretrotransposon-containing sequences showed a greater degree of placental hypomethylation than retrotransposons in every genomic element (intergenic, introns, and exons) except promoters. The differentially methylated fragments (DMFs) in placenta and neutrophils were enriched in gene-poor and CpG-poor regions. The placentally hypomethylated DMFs were enriched in genomic regions that are usually inactive, whereas hypermethylated DMFs were enriched in active regions. Hypomethylation of the human placenta is not specific to retroelements, indicating that the evolutionary advantages of placental hypomethylation go beyond those provided by expression of retrotransposons and retrogenes.

Smoking during pregnancy causes double-strand DNA break damage to the placenta

Despite the adverse effects of smoking, many pregnancies are exposed to tobacco smoke. Recent studies have investigated whether smoking damages placental DNA by measuring DNA adducts. This study investigated whether a more severe lesion, double-strand DNA breaks, was also present in the tobacco smoking-exposed placenta. Term placentae from women who smoked during their entire pregnancies (n = 52), from those who had ceased smoking for at least 4 weeks before delivery (previous smokers, n = 34), and from nonsmoking women (n = 150) were examined using the DNA double-strand break marker phosphorylated γ H2AX. The extent of DNA damage was assessed according to cell type and additional markers were applied for cell fate (apoptosis and DNA repair), and function (human chorionic gonadotropin, human placental lactogen, and glucose transporter 1), to characterize the effect of the DNA damage on placental integrity. Marked phosphorylated γ H2AX-positive cells occurred in the villous syncytiotrophoblast and syncytial knot nuclei in placentae from smokers (P < .001). Phosphorylated γ H2AX foci did not colocalize with the DNA repair protein 53BP1, and damaged nuclei had a marked reduction in expression of human chorionic gonadotropin, human placental lactogen, and glucose transporter 1. Minimal DNA damage, similar to nonsmokers, was present in previous smokers including those that had ceased smoking for just over 4 weeks before delivery. In summary, smoking during pregnancy was associated with marked double-strand DNA break damage to the syncytiotrophoblast. We suggest that smoking cessation is important to prevent additional DNA damage and to facilitate DNA repair.

A survey of New Zealand RANZCOG Fellows on their use of the levonorgestrel intrauterine device in adolescents

Background: The levonorgestrel intrauterine device (LNG‐IUD) is an established treatment for adult women. Although it is being used in adolescents, there is little published research in this age group to date. Recent reviews and editorials have challenged the long‐held views that intrauterine devices should not be used in young women.

Is there a correlation between bacterial vaginosis and preterm labour in women in the Otago region of New Zealand

Context:  While an association between bacterial vaginosis and preterm labour has been established, the relative contribution of this condition remains controversial.

Loss of ATRX and DAXX expression identifies poor prognosis for smooth muscle tumours of uncertain malignant potential and early stage uterine leiomyosarcoma

Uterine smooth muscle tumours of uncertain malignant potential (STUMP) are diagnostically and clinically challenging. The alternative lengthening of telomeres (ALT) telomere maintenance mechanism is associated with poor survival in soft tissue leiomyosarcoma. Time to first recurrence and survival were known for 18 STUMP and 43 leiomyosarcomata (LMS). These were screened for ALT telomere maintenance by the presence of ALT‐associated PML bodies (APBs) and for changes associated with the ALT phenotype, namely aberrant p53 expression, isocitrate dehydrogenase 1 mutation (R132H substitution) expression, mutant ATRX (αthalassemia/mental retardation syndrome X‐linked) expression and mutant DAXX (death‐domain‐associated protein) expression by immunohistochemistry (IHC). Overexpression of p16INK4A was examined immunohistologically in a subset of cases. Many of the tumours associated with death or recurrence demonstrated APBs commensurate with ALT telomere maintenance. However, all uterine STUMP (4/4), and vaginal STUMP (2/2) patients, and almost all LMS patients (88.4%, 23/26, including 90% (9/10) of stage 1 LMS cases), who had died of disease or who had recurrent disease, displayed loss of ATRX or DAXX expression. Loss of ATRX or DAXX expression identified poor prognosis (95% CI 2.1 to 40.8, p < 0.003), in the LMS group. Thus, loss of ATRX or DAXX expression in uterine smooth muscle tumours identifies a clinically aggressive molecular subtype of early stage LMS and when histopathological features are problematic such as in STUMP. As ATRX and DAXX IHC is readily performed in diagnostic laboratories these are potentially useful for routine histopathological classification and management.

Association of prior HPV vaccination with reduced preterm birth: A population based study

BACKGROUND Emerging evidence suggests that HPV infection is associated with negative pregnancy outcomes such as preterm birth (PTB), and pre-eclampsia. We aimed to determine if prior HPV vaccination reduced adverse pregnancy outcomes. METHODS A New Zealand population-based retrospective study linking first pregnancy outcome data (2008-2014 n = 35,646) with prior quadrivalent HPV vaccination status. Primary outcomes were likelihood (odds ratios, ORs) of PTB, pre-eclampsia, and stillbirth. Exposure groups were based on HPV vaccination. Adjusted ORs were calculated for each outcome, controlling for mothers age at delivery, ethnicity, socioeconomic status, health board region at time of delivery, and body mass index and smoking status at time of registration with maternity care provider. RESULTS Mothers mean age at delivery was 19 (SD 2.1) years. Of 34,994 the pregnancies included in the final study analyses 62.3% of women were unvaccinated, 11.0% vaccinated with one or two doses and 27.7% vaccinated with three doses prior to pregnancy. PTB (OR: 0.87; CI 0.78, 0.96)) was significantly lower for women who previously received the HPV vaccine. A dose response effect was found with each successive dose received decreasing the likelihood of PTB. No associations between the vaccinated and unvaccinated groups were shown for pre-eclampsia or stillbirth. CONCLUSIONS Prior receipt of the quadrivalent HPV vaccine was associated with a significant reduction in PTB (13%); suggesting that HPV vaccination may be effective in reducing PTB. The potential global public health impact is considerable and there is urgency to undertake further research to replicate and explore these findings.

Periconceptional folic acid use among women giving birth at Queen Mary Maternity Hospital in Dunedin

Background:  The New Zealand Ministry of Health advises that all women planning a pregnancy take a folic acid supplement to reduce the risk of having a neural tube defect (NTD)‐affected pregnancy. There is little information available to determine if women are following this advice.