Derivation and assessment of a sex-specific fetal growth standard.

PURPOSE: To derive a prescriptive sex-specific fetal growth standard and assess clinical management and outcomes according to sex-specific growth status. MATERIALS AND METHODS: This was a secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b), a prospective observational study of 10,038 nulliparas from eight U.S. centers who underwent ultrasounds at 14-20 and 22-29 weeks with outcomes ascertained after delivery. From these, we selected a nested cohort of lower risk participants (excluded those with chronic hypertension, pre-gestational diabetes, suspected aneuploidy, and preterm delivery) to derive a sex-specific equation for expected fetal growth using fetal weights by ultrasound and at birth. We compared the male-female discrepancy in the rate of weight <10th (small for gestational age [SGA]) and >90th (large for gestational age [LGA]) percentiles between the sex-specific and sex-neutral (Hadlock) standards. Using the full unselected cohort, we then assessed outcomes and clinical management according to sex-specific SGA and LGA status. RESULTS: Overall, 7280 infants in the lower risk nested cohort were used to derive a sex-specific equation with fetal sex included as an equation intercept. The sex-neutral standard diagnosed SGA more often in female newborns (21% vs. 13%, p < .001) and LGA more often in male newborns (5% vs. 3%, p < .001). The sex-specific standard resolved these disparities (SGA: 9% vs. 10%, p = .23; LGA: 13% vs. 13%, p = .58). To approximate an unselected population, 1059 participants initially excluded for risk factors for abnormal growth were then included for our secondary objective (N = 8339). In this unselected cohort, 39% (95% CI 37.0-42.0%) of the 1498 newborns classified as SGA by the sex-neutral standard were reclassified as appropriate for gestational age (AGA) by the sex-specific standard. These reclassified newborns were more likely to be delivered for growth restriction despite having lower risk of morbidity (females) or comparable risk of morbidity (males) compared to newborns considered AGA by both methods. Of the 6485 newborns considered AGA by the sex-neutral standard, 737 (11.4%, 95% CI 10.6-12.2%) were reclassified as LGA by the sex-specific standard. These reclassified newborns had higher rates of cesarean for arrest of descent, cesarean for arrest of dilation, and shoulder dystocia than newborns considered AGA by both methods. None were reclassified from LGA to AGA by the sex-specific standard. CONCLUSION: The Hadlock sex-neutral standard generates sex disparities in SGA and LGA at birth. Our sex-specific standard resolves these disparities and has the potential to improve accuracy of growth pathology risk stratification.

Clinical Implications of Second and Third Trimester Surveillance Ultrasounds of Growth-Restricted Fetuses.

Objective We sought to investigate the positive predictive value of ultrasound-diagnosed fetal growth restriction (FGR) for estimating small for gestational age (SGA) at birth. Secondary objectives were to describe clinical interventions performed as a result of FGR diagnosis. Study Design This was a retrospective cohort of pregnancies diagnosed with FGR over 3 years at a single institution. Maternal demographics, antenatal and delivery data, and neonatal data were collected. Descriptive statistics and linear regression were conducted. Results We included 406 pregnancies with diagnosis of FGR in second or third trimester. Median birth weight percentile was 17 (interquartile range: 5-50) and only 35.0% of these fetuses were SGA at birth. The positive predictive value of a final growth ultrasound below the 10th percentile for SGA at birth was 56.9%. Patients averaged eight additional growth ultrasounds following FGR diagnosis. One hundred and fourteen (28.1%) received antenatal steroids prior to delivery, and 100% of those delivered after more than 7 days following administration. There were 6 fetal deaths and 14 neonatal deaths. Conclusion In the majority of cases, pregnancies diagnosed with FGR during screening ultrasounds resulted in normally grown neonates and term deliveries. These patients may be receiving unnecessary ultrasounds and premature courses of corticosteroids.

Knowledge of Obstetric and Neonatal Danger Signs among Community Health Workers in the Rongo Sub-County of Migori County, Kenya: Results of a Community-based Cross-Sectional Survey.

In efforts to reduce maternal and neonatal mortality, it is recommended that all pregnant women be counseled on signs of pregnancy related complications and neonatal illness. In resource limited settings, such counselling may be task-shifted to lay health workers. We conducted a community-based cross-sectional survey of community health workers/volunteers in North and East Kamagambo of the Rongo Sub- County of Migori County, Kenya, between January-April 2018. A survey tool was administered through face-to-face interviews to investigate the level of knowledge of obstetric and neonatal danger signs among community health workers in North Kamagambo after one year of participation in the Lwala program, as well as to evaluate baseline knowledge of community health volunteers in East Kamagambo at the beginning of Lwala's expansion and prior to their receiving training from Lwala. The North Kamagambo group identified more danger signs in each category. The percentage of participants with adequate knowledge in the pregnancy, postpartum, and neonatal categories was significantly higher in North Kamagambo than in East Kamagambo. Sixty percent of participants in North Kamagambo knew 3 or more danger signs in 3 or more categories, compared to 24% of participants in East Kamagambo. Location in North Kamagambo (OR 2.526, p=0.03) and a shorter time since most recent training (OR 2.291, p=0.025) were associated with increased knowledge. Our study revealed varying levels of knowledge among two populations of lay health workers. This study highlights the benefit of frequent trainings and placing greater emphasis on identified gaps in knowledge of the labor and postpartum periods.

Sensitization of Drug Resistant Cancer Cells: A Matter of Combination Therapy.

Cancer drug resistance is an enormous problem. It is responsible for most relapses in cancer patients following apparent remission after successful therapy. Understanding cancer relapse requires an understanding of the processes underlying cancer drug resistance. This article discusses the causes of cancer drug resistance, the current combination therapies, and the problems with the combination therapies. The rational design of combination therapy is warranted to improve the efficacy. These processes must be addressed by finding ways to sensitize the drug-resistant cancers cells to chemotherapy, and to prevent formation of drug resistant cancer cells. It is also necessary to prevent the formation of cancer progenitor cells by epigenetic mechanisms, as cancer progenitor cells are insensitive to standard therapies. In this article, we emphasize the role for the rational development of combination therapy, including epigenetic drugs, in achieving these goals.

Cancer Progenitor Cells: The Result of an Epigenetic Event?

The concept of cancer stem cells was proposed in the late 1990s. Although initially the idea seemed controversial, the existence of cancer stem cells is now well established. However, the process leading to the formation of cancer stem cells is still not clear and thus requires further research. This article discusses epigenetic events that possibly produce cancer progenitor cells from predisposed cells by the influence of their environment. Every somatic cell possesses an epigenetic signature in terms of histone modifications and DNA methylation, which are obtained during lineage-specific differentiation of pluripotent stem cells, which is specific to that particular tissue. We call this signature an epigenetic switch. The epigenetic switch is not fixed. Our epigenome alters with aging. However, depending on the predisposition of the cells of a particular tissue and their microenvironment, the balance of the switch (histone modifications and the DNA methylation) may be tilted to immortality in a few cells, which generates cancer progenitor cells.

The Effects of Histone Deacetylase Inhibitor and Calpain Inhibitor Combination Therapies on Ovarian Cancer Cells.

BACKGROUND: Ovarian cancer is difficult to treat due to absence of selective drugs and tendency of platinum drugs to promote resistance. Combination therapy using epigenetic drugs is predicted to be a beneficial alternative. MATERIALS AND METHODS: This study investigated the effects of combination therapies using two structurally different histone deacetylase (HDAC) inhibitors (HDACi), sodium butyrate and suberanilohydroxamic acid (SAHA), with the calpain inhibitor calpeptin on two characteristically different ovarian cancer cell lines, CAOV-3 and SKOV-3. RESULTS: Suboptimal doses of HDACi and calpeptin produced several effects. Growth inhibition was enhanced and the epigenetically silenced tumor suppressor genes ARHI, p21 and RARß2 were re-expressed. Methylation of specific CpG residues in ARHI were reduced. Cell-cycle progression was inhibited and apoptosis, as well as autophagy, were induced. The phosphorylation of ERK and Akt were differentially effected by these inhibitors. CONCLUSION: The re-expression of tumor suppressors may sensitize ovarian cancer cells, which then undergo apoptosis and autophagy for cell death.

The Evolution of Epigenetics: From Prokaryotes to Humans and Its Biological Consequences.

The evolution process includes genetic alterations that started with prokaryotes and now continues in humans. A distinct difference between prokaryotic chromosomes and eukaryotic chromosomes involves histones. As evolution progressed, genetic alterations accumulated and a mechanism for gene selection developed. It was as if nature was experimenting to optimally utilize the gene pool without changing individual gene sequences. This mechanism is called epigenetics, as it is above the genome. Curiously, the mechanism of epigenetic regulation in prokaryotes is strikingly different from that in eukaryotes, mainly higher eukaryotes, like mammals. In fact, epigenetics plays a significant role in the conserved process of embryogenesis and human development. Malfunction of epigenetic regulation results in many types of undesirable effects, including cardiovascular disease, metabolic disorders, autoimmune diseases, and cancer. This review provides a comparative analysis and new insights into these aspects.

A Comparative Analysis of Genetic and Epigenetic Events of Breast and Ovarian Cancer Related to Tumorigenesis.

Breast cancer persists as the most common cause of cancer death in women worldwide. Ovarian cancer is also a significant source of morbidity and mortality, as the fifth leading cause of cancer death among women. This reflects the continued need for further understanding and innovation in cancer treatment. Though breast and ovarian cancer usually present as distinct clinical entities, the recent explosion of large-scale -omics research has uncovered many overlaps, particularly with respect to genetic and epigenetic alterations. We compared genetic, microenvironmental, stromal, and epigenetic changes common between breast and ovarian cancer cells, as well as the clinical relevance of these changes. Some of the most striking commonalities include genetic alterations of BRCA1 and 2, TP53, RB1, NF1, FAT3, MYC, PTEN, and PIK3CA; down regulation of miRNAs 9, 100, 125a, 125b, and 214; and epigenetic alterations such as H3K27me3, H3K9me2, H3K9me3, H4K20me3, and H3K4me. These parallels suggest shared features of pathogenesis. Furthermore, preliminary evidence suggests a shared epigenetic mechanism of oncogenesis. These similarities, warrant further investigation in order to ultimately inform development of more effective chemotherapeutics, as well as strategies to circumvent drug resistance.

EMT and tumor metastasis.

EMT and MET comprise the processes by which cells transit between epithelial and mesenchymal states, and they play integral roles in both normal development and cancer metastasis. This article reviews these processes and the molecular pathways that contribute to them. First, we compare embryogenesis and development with cancer metastasis. We then discuss the signaling pathways and the differential expression and down-regulation of receptors in both tumor cells and stromal cells, which play a role in EMT and metastasis. We further delve into the clinical implications of EMT and MET in several types of tumors, and lastly, we discuss the role of epigenetic events that regulate EMT/MET processes. We hypothesize that reversible epigenetic events regulate both EMT and MET, and thus, also regulate the development of different types of metastatic cancers.

Use of epigenetic drugs in disease: an overview.

Epigenetic changes such as DNA methylation and histone methylation and acetylation alter gene expression at the level of transcription by upregulating, downregulating, or silencing genes completely. Dysregulation of epigenetic events can be pathological, leading to cardiovascular disease, neurological disorders, metabolic disorders, and cancer development. Therefore, identifying drugs that inhibit these epigenetic changes are of great clinical interest. In this review, we summarize the epigenetic events associated with different disorders and diseases including cardiovascular, neurological, and metabolic disorders, and cancer. Knowledge of the specific epigenetic changes associated with these types of diseases facilitates the development of specific inhibitors, which can be used as epigenetic drugs. In this review, we discuss the major classes of epigenetic drugs currently in use, such as DNA methylation inhibiting drugs, bromodomain inhibitors, histone acetyl transferase inhibitors, histone deacetylase inhibitors, protein methyltransferase inhibitors, and histone methylation inhibitors and their role in reversing epigenetic changes and treating disease.

Drug resistance in cancer: an overview.

Cancers have the ability to develop resistance to traditional therapies, and the increasing prevalence of these drug resistant cancers necessitates further research and treatment development. This paper outlines the current knowledge of mechanisms that promote or enable drug resistance, such as drug inactivation, drug target alteration, drug efflux, DNA damage repair, cell death inhibition, and the epithelial-mesenchymal transition, as well as how inherent tumor cell heterogeneity plays a role in drug resistance. It also describes the epigenetic modifications that can induce drug resistance and considers how such epigenetic factors may contribute to the development of cancer progenitor cells, which are not killed by conventional cancer therapies. Lastly, this review concludes with a discussion on the best treatment options for existing drug resistant cancers, ways to prevent the formation of drug resistant cancers and cancer progenitor cells, and future directions of study.

Genetic and epigenetic aspects of breast cancer progression and therapy.

Although breast cancer is a heterogeneous disease that is challenging to characterize and treat, the recent explosion of genetic and epigenetic research may help improve these endeavors. In the present review, we use genetic diversity to characterize and classify different types of breast cancer. We also discuss genetic and epigenetic changes that are involved in the development of different breast cancer types and examine how these changes affect prognosis. It appears that while a combination of mutations and copy number changes determine the type of breast cancer, epigenetic alterations may be the primary initiators of cancer development. Understanding these critical biomarkers and molecular changes will advance our ability to effectively treat breast cancer. Next, we examine potential drug therapies directed at epigenetic changes, as such epigenetic drug treatments may prove useful for treating patient-specific tumors, breast cancer progenitor cells, and drug-resistant cells. Lastly, we discuss on mechanisms of carcinogenesis, including a novel hypothesis outlining the role of epigenetics in the development of cancer progenitor cells and metastasis. Overall, breast cancer subtypes may have a similar epigenetic signal that promotes cancer development, and treatment may be most effective if both epigenetic and genetic differences are targeted.

Demethylation and re-expression of epigenetically silenced tumor suppressor genes: sensitization of cancer cells by combination therapy.

Epigenetic regulation in eukaryotic and mammalian systems is a complex and emerging field of study. While histone modifications create an open chromatin conformation allowing for gene transcription, CpG methylation adds a further dimension to the expression of specific genes in developmental pathways and carcinogenesis. In this review, we will highlight DNA methylation as one of the distinct mechanisms for gene silencing and try to provide insight into the role of epigenetics in cancer progenitor cell formation and carcinogenesis. We will also introduce the concept of a dynamic methylation-demethylation system and the potential for the existence of a demethylating enzyme in this process. Finally, we will explain how re-expression of epigenetically silenced tumor suppressor genes could be exploited to develop effective drug therapies. In particular, we will consider how a combination therapy that includes epigenetic drugs could possibly kill cancer progenitor cells and reduce the chance of relapse following chemotherapy.

Anti-breast cancer effects of histone deacetylase inhibitors and calpain inhibitor.

Development of new breast cancer therapies is needed, particularly as cells become refractory or develop increased drug resistance. In an effort to develop such treatments, class I and II histone deacetylases (HDACs), alone and in combination with other cytotoxic agents, are currently in clinical trial. Herein, we discuss the effects of histone deacetylase inhibitors (HDACi) when used in combination with calpeptin, an inhibitor of the regulatory protease, calpain. We present results of study in two breast cancer cells lines with distinct characteristics: MDA-MB-231 and MCF-7. When used in combination with calpeptin, two chemically distinct HDACi significantly inhibited growth and increased cell death by inducing cell-cycle arrest and apoptosis. MCF-7 cells exhibited a greater proportion of arrest at the G(1) phase, whereas triple-negative MDA-MB-231 cells exhibited increased cell cycle arrest at the S phase. Methylation of the imprinted and silenced proapoptoic tumor suppressor gene aplasia Ras homolog member I (ARHI) was reduced in both cell lines after treatment with HDACi. However, it was only re-expressed on such treatment in MDA-MB-231 cells, suggesting that re-expression operates under differential mechanisms in these two cell lines. Collectively, these results showed that the combination of HDACi and calpeptin inhibited the growth of two distinctly different types of breast cancer cells and could have wide clinical applications, though the mechanisms of inhibition are possibly different.