Association of genetic disorders and congenital malformations with premature ovarian insufficiency: a nationwide register-based study

STUDY QUESTION

Are genetic disorders and congenital malformations associated with premature ovarian insufficiency (POI)?

SUMMARY ANSWER

A wide range of genetic disorder and congenital malformation diagnoses are associated with POI, especially early onset POI.

WHAT IS KNOWN ALREADY

POI is known to be associated with some genetic disorders, such as Turner syndrome and Fragile X premutation. Multiple genetic syndromes, such as ataxia teleangiectasia and galactosemia, have also been associated with an increased risk of POI, and many of these genetic syndromes manifest with various congenital malformations. In previous studies, a genetic aetiology has been found for 7-15% of POI cases.

STUDY DESIGN, SIZE, DURATION

This population-based study included 5011 women diagnosed with POI in 1988-2017. The data were collected from various national registries and covers women with POI nationwide.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We identified 5011 women diagnosed with POI from 1988 to 2017 from the drug reimbursement registry of the Social Insurance Institution of Finland. Women with surgical POI (bilateral oophorectomy for benign indications) were not included. We selected four population controls per woman with POI matched by month and year of birth and municipality of residence. Diagnostic codes for genetic disorders and congenital malformations (GD/CM) for the cases and controls were searched from the Hospital Discharge Register. Binary logistic regression was used to compare the odds for GD/CM among cases and controls. To minimize bias, for the statistical analyses, we excluded diagnoses which were reported <2 years prior to the index date.

MAIN RESULTS AND THE ROLE OF CHANCE

Of the women with POI, 15.9% (n = 797) had at least one diagnostic code for GD or CM. The odds ratio (OR) for Turner syndrome was 275 (95% CI 68.1-1110), and for other sex chromosome abnormalities, it was 12.7 (95% CI 4.1-39.1). For autosomal single gene disorders, the OR was 16.5 (95% CI 6.2-43.7). Women with POI had a higher odds of having a GD/CM diagnosis in all categories. The OR for GD/CM diagnoses was highest among the youngest POI patients (10-14 years old, OR 24.1, 95% CI 15.1-38.2). The odds of having POI were higher the more GD or CM diagnoses a woman had.

LIMITATIONS, REASONS FOR CAUTION

Some women with POI might not have sought help for their symptoms and therefore remain undiagnosed. Due to the register-based nature of our study, we did not have access to more specific genetic diagnoses than international classification of diseases offers.

WIDER IMPLICATIONS OF THE FINDINGS

GD/CM diagnoses were strongly associated with POI, especially when POI was diagnosed at a young age. The risk of POI was highest in women with multiple GD/CM diagnoses. Early onset POI can be a sign of underlying genetic disorder or congenital anomaly, and this should serve as a reminder for clinicians to consider further examinations. To avoid unnecessary delay in the diagnosis of POI and starting relevant hormone replacement therapy treatment, clinicians should be aware of these associations.

STUDY FUNDING/COMPETING INTEREST(S)

Oulu University Hospital financially supported this work. H.S. has received personal grants from the Finnish Menopause Society, Oulu Medical Research Foundation, and Finnish Research Foundation of Gynaecology and Obstetrics. S.S. has received grants from the Finnish Menopause Society, the Finnish Medical Foundation, and the Juho Vainio Foundation. None of the authors have any competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

BMI in childhood and adolescence is associated with impaired reproductive function-a population-based cohort study from birth to age 50 years

STUDY QUESTION

What is the association between childhood and adolescent BMI and reproductive capacity in women?

SUMMARY ANSWER

Adolescent girls with obesity had an increased risk of infertility and childlessness in adulthood independently of their marital status or the presence of polycystic ovary syndrome (PCOS).

WHAT IS KNOWN ALREADY

Girls with obesity (BMI (kg/m2)>95th percentile) more often exhibit menstrual irregularities and infertility problems as compared to those with normal weight, and premenarcheal girls with obesity have an increased risk of childlessness and infertility in adulthood. Follow-up studies on the relation between childhood and adolescence growth patterns and fertility or parity throughout the reproductive life span are limited.

STUDY DESIGN, SIZE, DURATION

A prospective, population-based cohort study (the Northern Finland birth cohort 1966) was performed with 5889 women born in 1966 and followed from birth to age 50 years. Postal questionnaires at ages 31 and 46 years addressed questions on reproductive capacity evaluated by decreased fecundability, need for infertility assessment and treatment by 46 years of age. Childlessness and number of children by age 50 years were recovered from registers. Women who did not report ever having attempted to achieve pregnancy (n = 1507) were excluded. The final study population included 4382 women who attempted to achieve pregnancy before age 46 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data on BMI were collected by trained personnel at all stages. We assessed association with both prospectively measured BMI at various time points and with early adiposity phenotypes derived from linear mixed models including the timing and the BMI at adiposity peak (AP) and adiposity rebound (AR). Self-reported infertility assessments and treatments were assessed at ages 31 and 46 years. Data on deliveries were collected from the national birth register. Decreased fecundability was defined at age 31 years as time to achieve pregnancy over 12 months. Logistic regression analyses were conducted with adjustments for marital status, education level and smoking at age 31 years. Women with PCOS were excluded from stratification-based sensitivity analyses. Obesity at a specific age group was defined by having at least one BMI value above the 95th percentile during the related period.

MAIN RESULTS AND THE ROLE OF CHANCE

BMI at the age of AR (5-7 years) was not associated with fertility outcomes after adjustments, but girls with AR <5.1 years had a higher risk of remaining childless compared to girls with AR over 5.1 years (adjusted odds ratio (OR): 1.45 (1.10-1.92)). At ages 7-10 and 11-15 years, obesity was associated with decreased fecundability (adjusted OR 2.05 (1.26-3.35) and 2.04 (1.21-3.44), respectively) and a lower number of children. At age 11-15 years, both overweight and obesity were associated with a higher risk of childlessness (adjusted OR 1.56 (1.06-2.27), 1.77 (1.02-3.07), respectively), even after excluding women with PCOS. Underweight at age 11-15 years was associated with an increased risk for infertility treatment (adjusted OR 1.55 (1.02-2.36)) and a tendency for an increased risk for infertility assessment (adjusted OR 1.43 (0.97-2.10)) after excluding women with PCOS.

LIMITATIONS, REASON FOR CAUTION

Despite a high participation rate throughout the follow-up, some growth data for children over the different age groups were missing. Infertility outcomes were self-reported. A potential over-diagnosis of obesity may have reduced the significance of the association between childhood obesity and fertility outcomes, and the diagnosis of PCOS was self-reported.

WIDER IMPLICATIONS OF THE FINDINGS

This study supports previous results showing that girls with obesity in late childhood and in adolescence displayed reduced fertility and an increased risk of remaining childless in adulthood, independently of marital history and PCOS in adulthood. These findings corroborate the body of evidence for a causal relation between early adiposity and the reproductive functions in women. We recommend reinforcing the prevention of obesity in school-age girls to reduce the risk of impaired reproductive functions.

STUDY FUNDING/COMPETING INTEREST(S)

NFBC1966 received financial support from University of Oulu Grant no. 65354, Oulu University Hospital Grant no. 2/97, 8/97, Ministry of Health and Social Affairs Grant no. 23/251/97, 160/97, 190/97, National Institute for Health and Welfare, Helsinki Grant no. 54121, Regional Institute of Occupational Health, Oulu, Finland Grant no. 50621, 54231. The Finnish Medical Foundation, the North Ostrobothnia Regional Fund, the Academy of Finland (project grants 315921, 104781, 120315, 129269, 1114194, 24300796), Center of Excellence in Complex Disease Genetics and SALVE, the Sigrid Juselius Foundation, Biocenter Oulu, University Hospital Oulu and University of Oulu (75617), Jalmari ja Rauha Ahokkaan säätiö, The Finnish Medical Foundation, Medical Research Center Oulu, National Institute for Health Research (UK). M. R. J., S. S. and R. N. received funding by the Academy of Finland (#268336) and the European Union's Horizon 2020 research and innovation program (under Grant agreement no. 633595 for the DynaHEALTH action and GA 733206 for LifeCycle). The funders had no role in study design, in the collection, analysis and interpretation of the data, in the writing of the article and in the decision to submit it for publication. The authors have no conflict of interest to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Management of polycystic ovary syndrome in childhood and adolescence

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women. It may manifest as early as in the first decade of life. Most often it becomes clinically apparent during adolescence with maturation of the hypothalamic-pituitary-ovarian axis.

CLINICAL FEATURES

Typical features in adolescence include irregular menstrual cycles, acne, hirsutism, obesity and signs of insulin resistance such as acanthosis nigricans. Biochemical hyperandrogenism and polycystic ovaries are often present. However, some adolescents have no evidence of clinical and biochemical hyperandrogenism despite dysfunctional polycystic ovaries.

PATHOGENESIS

The pathogenesis of PCOS is uncertain, however, both genetic and environmental factors play a role, resulting in key features of the syndrome; disordered gonadotropin release, dysregulated steroidogenesis, ovarian and adrenal hyperandrogenism and hyperinsulinism. PCOS is often accompanied by metabolic syndrome, with abnormalities in lipid and glucose metabolism.

TREATMENT

Treatment of PCOS is symptomatic. Lifestyle changes are a first-line intervention, however, increasing evidence suggests that metformin and estrogen-progestin combination pill may be beneficial.

CONCLUSIONS

PCOS is a lifelong condition that carries long-term health risks. Several risk factors for PCOS have been identified and clinicians should be alert for this condition already in childhood and adolescence. Early intervention and counseling might be the key for prevention of co-morbidities of PCOS.

Bruton's tyrosine kinase together with PI 3-kinase are part of Toll-like receptor 2 multiprotein complex and mediate LTA induced Toll-like receptor 2 responses in macrophages

Lipoteichoic acid (LTA) of Gram-positive bacteria initiates innate immune responses via Toll-like receptor-2 (TLR2), resulting in the activation of intracellular signaling and production of inflammatory cytokines in macrophages. Although Bruton's tyrosine kinase (Btk) is biologically important molecule implicated in immune regulation and recently in TLR signaling its importance for LTA-TLR2 mediated responses has not been evaluated. In this study, we detected Btk in the LTA signaling complex with TLR2 and PI 3-kinase (PI3K). The constitutive interaction of these proteins was mediated via PI3K Src homology (SH3) -domain. Both Btk and PI3K were activated by LTA stimulation and the LTA induced cytokine expression was differentially modulated by these kinases. LTA induced the activation of nuclear factor kappaB (NFkappaB), however, only Btk inhibition affected the LTA induced Ser536 phosphorylation and DNA-binding of NFkappaB. In conclusion, our results demonstrate that Btk and PI3K occupy important roles in TLR2-induced activation of macrophages, resulting in selective regulation of cytokines.

The adaptor protein Crk connects multiple cellular stimuli to the JNK signaling pathway

c-Jun N-terminal kinases (JNKs) are potently activated by a number of cellular stimuli. Small GTPases, in particular Rac, are responsible for initiating the activation of the JNK pathways. So far, the signals leading from extracellular stimuli to the activation of Rac have remained elusive. Recent studies have demonstrated that the Src homology 2 (SH2)- and Src homology 3 (SH3)-containing adaptor protein Crk is capable of activating JNK when ectopically expressed. We found here that transient expression of Crk induces JNK activation, and this activation was dependent on both the SH2- and SH3-domains of Crk. Expression of p130(Cas) (Cas), a major binding protein for the Crk SH2-domain, also induced JNK activation, which was blocked by the SH2-mutant of Crk. JNK activation by Cas and Crk was effectively blocked by a dominant-negative form of Rac, suggesting for a linear pathway from the Cas-Crk-complex to the Rac-JNK activation. Many of the stimuli that activate the Rac-JNK pathway enhance engagement of the Crk SH2-domain. JNK activation by these stimuli, such as epidermal growth factor, integrin ligand binding and v-Src, was efficiently blocked by dominant-negative mutants of Crk. A dominant-negative form of Cas in turn blocked the integrin-, but not epidermal growth factor - nor v-Src-mediated JNK activation. Together, these results demonstrate an important role for Crk in connecting multiple cellular stimuli to the Rac-JNK pathway, and a role for the Cas-Crk complex in integrin-mediated JNK activation.

Oncogenic forms of Cbl abrogate the anchorage requirement but not the growth factor requirement for proliferation

Recent studies have demonstrated that Cbl, the 120 kDa protein product of the c-cbl proto-oncogene, becomes tyrosine phosphorylated in response to stimulation of growth factor receptors and upon integrin-mediated cell adhesion. As a result, Cbl forms complexes with SH2 and SH3 domain-containing proteins, pointing to its role in signal transduction. The cellular form of Cbl can be rendered into transforming by naturally occurring or engineered mutations to its amino acid sequence. To gain insight into the mechanisms how oncogenic forms of Cbl render cells tumorigenic and what the function of the cellular Cbl might be, we have undertaken an analysis of NIH3T3 cells transfected with wild-type and oncogenic forms of Cbl. We demonstrate that unlike cellular Cbl, the mutant forms of Cbl are tyrosine phosphorylated in an adhesion-independent manner and interact with and activate SH2-containing signaling molecules in both suspended and adherent cells. Our data further show that oncogenic forms of Cbl induce anchorage-independent but serum-dependent growth. These results support the view that transformation by oncogenic forms of Cbl results from constitutive activation of integrin-dependent, rather than growth factor-dependent signaling events and, as a corollary, suggest that cellular Cbl might be a functionally important mediator of integrin signaling.

Epidermal growth factor modulates tyrosine phosphorylation of p130Cas. Involvement of phosphatidylinositol 3'-kinase and actin cytoskeleton

Epidermal growth factor (EGF) treatment of Rat-1 cells expressing human EGF receptor results in the modification of the tyrosine phosphorylation of the p130 Crk-associated substrate (Cas), a novel signaling molecule residing in focal adhesions. At low, mitogenic concentrations (<10 ng/ml), EGF treatment induced a rapid and transient tyrosine phosphorylation of Cas and promoted the formation of a Cas-adapter protein Crk complex in intact cells. The increase in tyrosine phosphorylation of Cas paralleled an increase in the cellular content of actin stress fibers and occurred via a pathway that depended on the integrity of the cytoskeleton. Further, phosphatidylinositol 3'-kinase activity was found to be required for the EGF-stimulated Cas phosphorylation and actin polymerization. At high concentrations (>30 ng/ml), EGF treatment resulted in the tyrosine dephosphorylation of Cas in a time-dependent manner with a concomitant decrease in the length and number of actin stress fibers. Thus, Cas exhibits an unusual bell-shaped dose-response curve in response to EGF stimulation. These results demonstrate a novel signaling role for EGF in inducing changes in tyrosine phosphorylation of Cas and Cas-Crk complex formation and suggest that Cas could be a signaling component in EGF-mediated signal transduction.

The proto-oncogene product p120(cbl) links c-Src and phosphatidylinositol 3'-kinase to the integrin signaling pathway

Integrin-mediated cell adhesion triggers intracellular signaling cascades, including tyrosine phosphorylation of intracellular proteins. We show in this report that p120(cbl) (Cbl), the 120-kDa c-cbl proto-oncogene product, becomes tyrosine-phosphorylated during integrin-mediated macrophage cell adhesion to extracellular matrix substrata and anti-integrin antibodies. This tyrosine phosphorylation does not occur when cells attach to polylysine, to which cells adhere in a nonspecific fashion. It also does not take place when adhesion-induced reorganization of the cytoskeleton is inhibited with cytochalasin D. In contrast to the rapid and transient tyrosine phosphorylation of Cbl by CSF-1 stimulation, tyrosine phosphorylation of Cbl by cell attachment was gradual and persistent. Tyrosine-phosphorylated Cbl was found to form complexes with the SH2 domain-containing signaling proteins Src and phosphatidylinositol 3-kinase; in vitro kinase assays demonstrated that these kinases were active in the Cbl complexes following integrin ligand binding. Furthermore, Cbl was found to translocate to the plasma membrane in response to cell adhesion to fibronectin. These observations suggest that Cbl serves as a docking protein and may transduce signals to downstream signaling pathways following integrin-mediated cell adhesion in macrophages.