Premature ovarian aging in BRCA carriers: a prototype of systemic precocious aging?

Somatic mutations in aging and disease

Time always leaves its mark, and our genome is no exception. Mutations in the genome of somatic cells were first hypothesized to be the cause of aging in the 1950s, shortly after the molecular structure of DNA had been described. Somatic mutation theories of aging are based on the fact that mutations in DNA as the ultimate template for all cellular functions are irreversible. However, it took until the 1990s to develop the methods to test if DNA mutations accumulate with age in different organs and tissues and estimate the severity of the problem. By now, numerous studies have documented the accumulation of somatic mutations with age in normal cells and tissues of mice, humans, and other animals, showing clock-like mutational signatures that provide information on the underlying causes of the mutations. In this review, we will first briefly discuss the recent advances in next-generation sequencing that now allow quantitative analysis of somatic mutations. Second, we will provide evidence that the mutation rate differs between cell types, with a focus on differences between germline and somatic mutation rate. Third, we will discuss somatic mutational signatures as measures of aging, environmental exposure, and activities of DNA repair processes. Fourth, we will explain the concept of clonally amplified somatic mutations, with a focus on clonal hematopoiesis. Fifth, we will briefly discuss somatic mutations in the transcriptome and in our other genome, i.e., the genome of mitochondria. We will end with a brief discussion of a possible causal contribution of somatic mutations to the aging process.

Reproductive outcomes in women with BRCA 1/2 germline mutations: A retrospective observational study and literature review

Objective

To evaluate the reproductive outcomes of patients bearing BRCA-1 and BRCA-2 mutations.

Methods

In this retrospective observational cohort study, we assessed data from BRCA-1 and BRCA-2 carriers, analyzing demographics, oncological history, and reproductive outcomes. Statistical analysis compared BRCA-1 and BRCA-2 carriers. A thorough review of the literature was carried out.

Results

Fifty-eight patients were included. BRCA-1 and BRCA-2 mutations were equally distributed. Eighty-nine pregnancies occurred in our series, hesitated in 73 live births and 19 miscarriages. Mean age at first and last pregnancy was 27.8 ± 4.8 and 31.6 ± 4.8 years old. Thirty-nine patients have had at least one live birth (67.2%). Mean number of live births was 1.9 ± 0.6. Live birth rate (LBR) was 81.1% and miscarriage rate was 32.8%. Spontaneous fertility was unaltered, as evidenced by high LBR. Subgroup analysis revealed no significant differences between BRCA-1 and BRCA-2 carriers.

Conclusions

Our results shows that spontaneous reproductive outcomes in BRCA-mutated patients are reassuring. Despite evidence indicating a decrease in ovarian reserve among BRCA patients, this factor seems to not impact spontaneous fertility negatively. Further research is needed, and individuals with BRCA mutations should consider early family planning and fertility preservation in case of partner absence.

Ovarian stimulation and oocyte cryopreservation in females with cancer

PURPOSE OF REVIEW

We reviewed the most recent developments including the safety and effectiveness data and success rates in individualized ovarian stimulation protocols for adult and postpubertal females with cancer.

RECENT FINDINGS

In women with breast cancer, aromatase inhibitor- and tamoxifen-supplemented stimulation protocols increase the margin of safety by limiting estrogen exposure. The outcomes of ovarian stimulation appear similar between cancer and noncancer populations, even with the recently developed random-start protocols, which allow initiation of ovarian stimulation anytime during the menstrual cycle. Based on lower anti-Mullerian hormone levels and primordial follicle density, carriers of BRCA pathogenic variants ( BRCApv ) have decreased ovarian reserve in comparison to women without those variants and may lose larger portion of their ovarian reserve post chemotherapy. Oocyte cryopreservation is also emerging as a suitable fertility preservation approach for selected postpubertal girls as young as 12 years of age.

SUMMARY

Individualized ovarian stimulation approaches combined with improvements in cryopreservation techniques increased the success and safety margin to preserve fertility with oocyte freezing. Women with BRCApv , on the other hand, may be at disadvantage as they have lower ovarian reserve and may lose larger portion of their ovarian reserve post chemotherapy compared to women who do not carry these variants.

BRCA Mutations-The Achilles Heel of Breast, Ovarian and Other Epithelial Cancers

Two related tumor suppressor genes, BRCA1 and BRCA2, attract a lot of attention from both fundamental and clinical points of view. Oncogenic hereditary mutations in these genes are firmly linked to the early onset of breast and ovarian cancers. However, the molecular mechanisms that drive extensive mutagenesis in these genes are not known. In this review, we hypothesize that one of the potential mechanisms behind this phenomenon can be mediated by Alu mobile genomic elements. Linking mutations in the BRCA1 and BRCA2 genes to the general mechanisms of genome stability and DNA repair is critical to ensure the rationalized choice of anti-cancer therapy. Accordingly, we review the literature available on the mechanisms of DNA damage repair where these proteins are involved, and how the inactivating mutations in these genes (BRCAness) can be exploited in anti-cancer therapy. We also discuss a hypothesis explaining why breast and ovarian epithelial tissues are preferentially susceptible to mutations in BRCA genes. Finally, we discuss prospective novel therapeutic approaches for treating BRCAness cancers.

BRCA, infertility, and fertility preservation: a review for counseling

BRCA mutations as a triggering factor in breast cancer have been reported to result in fertility problems and oocyte aging in young patients with cancer diagnosis. These patients are concerned about fertility problems and family planning before undergoing treatment modalities that may result in infertility. In this review, we conducted analysis of the literature on the association between BRCA mutations and infertility, possible fertility preservation options, and their safety and tried to gather results from different disciplines and points of view on the matter. Our aim is to provide a general summary of recent studies to provide further insight on the matter for counseling BRCA mutation carriers on fertility preservation methods and their implications.

Vasoactive intestinal peptide deficiency promotes ovarian dysfunction associated to a proinflammatory microenvironment reminiscent of premature aging

Complex immune regulation during pregnancy is required to ensure a successful pregnancy outcome. Vasoactive intestinal peptide (VIP) has local immunoregulatory effects on the ovary, uterus and maternal-fetal interface that favor a tolerogenic maternal microenvironment. Since the VIP Knockout (KO) mice are subfertile, we investigated the mechanisms underlying the effects of VIP deficiency on ovarian physiology and immune homeostasis. Therefore, we studied VIP KO, deficient (HT) and wild type (WT) female mice in estrus at 3 or 8 months of age. Young KO mice showed abnormal cycle timing and regularity associated with dysfunctional ovaries. Ovaries presented higher number of atretic follicles and reduced number of corpora lutea leading to a lower ovulation rates. Part of the VIP KO mice (25 %) failed to ovulate or ovulated oocytes incompetent to be fertilized (50 %). In particular, ovaries of young KO mice exhibited features of premature aging accompanied by a pro-inflammatory milieu with increased levels of IL-1β. A unique macrophage subpopulation identified as "foamy macrophages" was found. On the other hand, aged VIP KO females did not gain body weight probably due to the sustained production of E2. Finally, the adoptive transfer of FOXP3+ cells to infertile VIP KO females resulted in their selective recruitment to the ovary. It increased FOXP3/RORγt and TGFβ/IL-6 ratio improving ovarian microenvironment and pregnancy rate. The present results suggest that VIP contributes to ovarian homeostatic mechanisms required for a successful pregnancy.

Breaking the aging epigenetic barrier

Aging is an inexorable event occurring universally for all organisms characterized by the progressive loss of cell function. However, less is known about the key events occurring inside the nucleus in the process of aging. The advent of chromosome capture techniques and extensive modern sequencing technologies have illuminated a rather dynamic structure of chromatin inside the nucleus. As cells advance along their life cycle, chromatin condensation states alter which leads to a different epigenetic landscape, correlated with modified gene expression. The exact factors mediating these changes in the chromatin structure and function remain elusive in the context of aging cells. The accumulation of DNA damage, reactive oxygen species and loss of genomic integrity as cells cease to divide can contribute to a tumor stimulating environment. In this review, we focus on genomic and epigenomic changes occurring in an aged cell which can contribute to age-related tumor formation.

Bone health after RRBSO among BRCA1/2 mutation carriers: a population-based study

OBJECTIVE

Examine the risks of fractures and osteoporosis after risk-reducing bilateral salpingo-oophorectomy (RRBSO) among women with BRCA1/2 mutations.

METHODS

In this retrospective population-based study in British Columbia, Canada, between 1996 to 2017, we compared risks of osteoporosis and fractures among women with BRCA1/2 mutations who underwent RRBSO before the age of 50 (n=329) with two age-matched groups without known mutations: 1) women who underwent bilateral oophorectomy (BO) (n=3,290); 2) women with intact ovaries who had hysterectomy or salpingectomy (n=3,290). Secondary outcomes were: having dual-energy X-ray absorptiometry (DEXA) scan, and bisphosphonates use.

RESULTS

The mean age at RRBSO was 42.4 years (range, 26-49) and the median follow-up for women with BRCA1/2 mutations was 6.9 years (range, 1.1-19.9). There was no increased hazard of fractures for women with BRCA1/2 mutations (adjusted hazard ratio [aHR]=0.80; 95% confidence interval [CI]=0.56-1.14 compared to women who had BO; aHR=1.02; 95% CI=0.65-1.61 compared to women with intact ovaries). Among women who had DEXA-scan, those with BRCA1/2 mutations had higher risk of osteoporosis (aHR=1.60; 95% CI=1.00-2.54 compared to women who had BO; aHR=2.49; 95% CI=1.44-4.28 compared to women with intact ovaries). Women with BRCA1/2 mutations were more likely to get DEXA-scan than either control groups, but only 46% of them were screened. Of the women with BRCA1/2 mutations diagnosed with osteoporosis, 36% received bisphosphonates.

CONCLUSION

Women with BRCA1/2 mutations had higher risk of osteoporosis after RRBSO, but were not at increased risk of fractures during our follow-up. Low rates of DEXA-scan and bisphosphonates use indicate we can improve prevention of bone loss.

VTT, J.C. EM, G.W.M. LE, Irene H, Mariette G, J.T. VGR, Willem V, D. LK, J.M. BF, M.E. BA. The Impact of BRCA1- and BRCA2 Mutations on Ovarian Reserve Status

This study aimed to investigate whether female BRCA1- and BRCA2 mutation carriers have a reduced ovarian reserve status, based on serum anti-Mullerian hormone (AMH) levels, antral follicle count (AFC) and ovarian response to ovarian hyperstimulation. A prospective, multinational cohort study was performed between October 2014 and December 2019. Normo-ovulatory women, aged 18-41 years old, applying for their first PGT-cycle for reason of a BRCA mutation (cases) or other genetic diseases unrelated to ovarian reserve (controls), were asked to participate. All participants underwent a ICSI-PGT cycle with a long-agonist protocol for controlled ovarian hyperstimulation. Linear and logistic regression models were used to compare AMH, AFC and ovarian response in cases and controls. Sensitivity analyses were conducted on BRCA1- and BRCA2 mutation carrier subgroups. Thirty-six BRCA mutation carriers (18 BRCA1- and 18 BRCA2 mutation carriers) and 126 controls, with mean female age 30.4 years, were included in the primary analysis. Unadjusted median AMH serum levels (IQR) were 2.40 (1.80-3.00) ng/ml in BRCA mutation carriers and 2.15 (1.30-3.40) ng/ml in controls (p = 0.45), median AFC (IQR) was 15.0 (10.8-20.3) and 14.5 (9.0-20.0), p = 0.54, respectively. Low response rate was 22.6% among BRCA mutation carriers and 9.3% among controls, p = 0.06. Median number of retrieved oocytes was 9 (6-14) in carriers and 10 (7-13) in controls, p = 0.36. No substantial differences were observed between BRCA1- and BRCA2 mutation carriers. Based on several biomarkers, no meaningful differences in ovarian reserve status were observed in female BRCA mutation carriers compared to controls in the context of ICSI-PGT treatment.

Irinotecan (CPT-11) Treatment Induces Mild Gonadotoxicity

BACKGROUND

Gonadal toxicity following chemotherapy is an important issue among the population of young cancer survivors. The inhibitor of DNA topoisomerase I, irinotecan (CPT-11), is widely used for several cancer types. However, little is known about the effect of irinotecan on the fertility of both genders. Thus, the aim of the present study was to evaluate irinotecan gonadotoxicity, using a mouse model.

METHODS

Mature male and female mice were injected intraperitoneally with either saline (), irinotecan (100 mg/kg) or cyclophosphamide (100 mg/kg); and sacrificed one week or three months later for an acute or long-term toxicity assessment, respectively. We used thorough and advanced fertility assessment by already established methods: Gonadal and epididymal weights, as well as sperm count and sperm motility were determined; serum anti-Müllerian hormone (AMH) was measured by ELISA. Immunohistochemistry (Ki-67), immunofluorescence (PCNA, CD34), terminal transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) and computerized analysis were performed to examine gonadal proliferation, apoptosis and vascularization. qPCR was used to assess the amount of testicular spermatogonia (Id4 and Gafra1 mRNA) and ovarian primordial oocytes reserves (Sohlh2, Nobox and Figla mRNA).

RESULTS

Females: Irinotecan administration induced acute ovarian apoptosis and decreased vascularity, as well as a mild, statistically significant, long-term decrease in the number of growing follicles, ovarian weight, and ovarian reserve. Males: Irinotecan administration caused an acute testicular apoptosis and reduced testicular spermatogenesis, but had no effect on vascularity. Irinotecan induced long-term decrease of testicular weight, sperm count and testicular spermatogonia and caused elevated serum AMH.

CONCLUSION

Our findings imply a mild, though irreversible effect of irinotecan on mice gonads.

Ovarian reserve of women with and without BRCA pathogenic variants: A systematic review and meta-analysis

INTRODUCTION

Preliminary clinical evidence suggests a detrimental effect of pathogenic variants of BRCA1 and 2 genes on fertility outcome. This meta-analysis evaluates whether women carrying BRCA mutations (BRCAm) have decreased ovarian reserve, in terms of Anti-Muellerian Hormone (AMH), compared to women without BRCAm (wild-type).

MATERIAL AND METHODS

Systematic searches of PubMed, Medline, Scopus, Embase, Science Direct and the Cochrane Library from inception until July 2020 were conducted. All studies comparing AMH level in fertile age women, with and without BRCA pathogenic variants were considered. Sub-analyses were performed according to age, presence of breast cancer, and type of mutation.

RESULTS

Among 64 studies, 10 series were included. For the entire cohort, a trend of reduced AMH level were found between BRCAm carriers and women without pathogenic variants. BRCAm carriers aged 41-years or younger had lower AMH levels compared to 41-years or younger wild type women (OR: 0.73 [95%CI-1.12;-0.35]; p = 0.0002). This finding was confirmed for BRCA1m carriers (OR: 1 [95%CI-1.96;-0.05]; p = 0.004) whereas no difference was observed between BRCA2m carriers and wild type women. The same analysis on breast cancer patients with and without BRCAm achieved the same results.

CONCLUSION

Young BRCA1m carriers seem to have lower AMH level compared with wild type women and therefore a potential decreased ovarian reserve.

Reproductive issues in carriers of germline pathogenic variants in the BRCA1/2 genes: an expert meeting

BACKGROUND

Healthy individuals and patients with cancer who are carriers of germline pathogenic variants in the BRCA1/2 genes face multiple reproductive challenges that require appropriate counseling and specific expertise.

MAIN BODY

On December 5th-7th, 2019, patient advocates and physicians with expertise in the field of reproductive medicine, fertility preservation, and oncology were invited to "San Giuseppe Moscati" Hospital in Avellino (Italy) for a workshop on reproductive management of women with germline pathogenic variants in the BRCA1/2 genes. From the discussion regarding the current evidence and future prospective in the field, eight main research questions were formulated and eight recommendations were developed regarding fertility, fertility preservation, preimplantation genetic testing, and pregnancy in healthy carriers and patients with cancer.

CONCLUSION

Several misconceptions about the topic persist among health care providers and patients often resulting in a discontinuous and suboptimal management. With the aim to offer patient-tailored counseling about reproductive issues, both awareness of current evidences and research should be promoted.

Risk of cardiovascular disease among women carrying BRCA mutations after risk-reducing bilateral salpingo-oophorectomy: A population-based study

OBJECTIVE

Examine the risk of cardiovascular disease (CVD) following risk reducing bilateral salpingo-oophorectomy (RRBSO) among women with BRCA mutations.

METHODS

In this retrospective population-based study in British Columbia, Canada, between 1996 and 2017, we compared the risk of CVD among women with known BRCA mutations who underwent RRBSO before the age of 50 (n = 360) with two groups of age-matched women without known BRCA mutations: 1) women who underwent bilateral oophorectomy (BO) for benign conditions (n = 3600); and, 2) women with intact ovaries who had hysterectomy or salpingectomy (n = 3600). Our primary outcome was CVD (a composite (any of) myocardial infarction, heart failure, and/or cerebrovascular disease). Secondary outcomes included a diagnostic code for predisposing conditions (hypertension, dyslipidemia, and/or diabetes mellitus), and use of cardioprotective medications (statins and/or beta-blockers).

RESULTS

We report no significant increased risk for CVD between women with BRCA mutations and women who underwent BO (aHR = 1.08, 95%CI: 0.72-1.62), but women with BRCA mutations were less likely to be diagnosed with predisposing conditions (aHR = 0.69, 95%CI: 0.55-0.85). Compared to women without BRCA mutations with intact ovaries who underwent hysterectomy or salpingectomy, women with BRCA mutations had significantly increased risk for CVD (aHR = 1.82, 95%CI: 1.18-2.79) and were less likely to be diagnosed with predisposing conditions (aHR = 0.78, 95%CI: 0.62-0.97) and to fill cardioprotective medications (aHR = 0.88, 95%CI: 0.64-1.22).

CONCLUSION

Our results suggest an opportunity for improved prevention of CVD in women with BRCA mutations after prophylactic oophorectomy. Despite the observed lower prevalence of predisposing conditions for CVD and lesser use of cardioprotective medications, this population did not have a lower rate of CVD.

Association of Germline BRCA Pathogenic Variants With Diminished Ovarian Reserve: A Meta-Analysis of Individual Patient-Level Data

PURPOSE

To determine whether germline BRCA (gBRCA) pathogenic variants are associated with decreased ovarian reserve.

MATERIALS AND METHODS

An individual patient-level data meta-analysis was performed using five data sets on 828 evaluable women who were tested for gBRCA. Of those, 250 carried gBRCA, whereas 578 had tested negative and served as controls. Of the women with gBRCA, four centers studied those affected with breast cancer (n = 161) and one studied unaffected individuals (n = 89). The data were adjusted for the center, age, body mass index, smoking, and oral contraceptive pill use before the final analysis. Anti-Müllerian hormone (AMH) levels in affected women were drawn before presystemic therapy.

RESULTS

The mean age of women with versus without gBRCA1/2 (34.1 ± 4.9 v 34.3 ± 4.8 years; P = .48) and with gBRCA1 versus gBRCA2 (33.7 ± 4.9 v 34.6 ± 4.8 years; P = .16) was similar. After the adjustments, women with gBRCA1/2 had significantly lower AMH levels compared with controls (23% lower; 95% CI, 4 to 38; P = .02). When the adjusted analysis was limited to affected women (157 with gBRCA v 524 without, after exclusions), the difference persisted (25% lower; 95% CI, 9 to 38; P = .003). The serum AMH levels were lower in women with gBRCA1 (33% lower; 95% CI, 12 to 49; P = .004) but not gBRCA2 compared with controls (7% lower; 95% CI, 31% lower to 26% higher; P = .64).

CONCLUSION

Young women with gBRCA pathogenic variants, particularly those affected and with gBRCA1, have lower serum AMH levels compared with controls. They may need to be preferentially counseled about the possibility of shortened reproductive lifespan because of diminished ovarian reserve.

BRCA 1, 2 mutation and earlier menopause. Could BRCA 1, 2 be used as predictor of menopause?

Many studies have shown that BRCA mutation is not only related to cancer but also to ovarian aging. Studies in both human and mice oocytes have shown that Double-strand breaks (DSBs) accumulate with age. Genome-wide association studies (GWAS) have found 44 genetic loci that are related to variations when a female is about to have menopause. BRCA1 is involved in these 44 loci that are associated with the age of menopause. This review has gathered all results of literature search about the association between BRCA genes and early menopause. The majority of the articles found that women with BRCA mutation have earlier menopause compared to non-carriers. In conclusion, in the near future BRCA1,2 genes could be used as predictive biomarkers of menopause.

Fertility treatments and breast cancer risk in Jewish Israeli BRCA mutation carriers

OBJECTIVE

To determine whether fertility treatments impact the risk of breast cancer in Jewish Israeli BRCA1/2 mutation carriers.

DESIGN

Historical cohort study.

SETTING

University-affiliated tertiary medical center.

PATIENT(S)

A total of 1,824 Jewish Israeli BRCA1/2 mutation carriers from a single center were stratified into 1,492 (81.8%) carriers who were not treated for infertility and 332 (18.2%) carriers who underwent fertility treatment with clomiphene citrate (n = 134), gonadotropin (n = 119), in vitro fertilization (n = 183), or a combination of treatments (n = 89).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Hazard ratios (HR) and 95% confidence intervals (CI) for the association of breast cancer with fertility treatment and other hormonal and reproductive variables.

RESULT(S)

Breast cancer was diagnosed in 687 BRCA1/2 mutation carriers. Multivariate analysis, either of the whole group or stratified by each gene, showed no association between fertility treatment and breast cancer risk, regardless of the type of treatment (clomiphene citrate: HR 0.77, 95% CI 0.49-1.19; gonadotropin: HR 0.54, 95% CI 0.28-1.01; in vitro fertilization: HR 0.65, 95% CI 0.39-1.08; and combined treatments: HR 1.23, 95% CI 0.49-3.06). An increased breast cancer risk was associated with paternal origin of the mutation (HR 1.43, 95% CI 1.17-1.75) and use of oral contraceptives for >5 years (HR 1.62, 95% CI 1.27-2.06) in both BRCA1 and BRCA2 mutation carriers. Ovarian cancer risk was decreased with the use of any oral contraceptive (HR 0.61; 95% CI 0.46-0.82).

CONCLUSION(S)

Fertility treatment for BRCA1/2 mutation carriers is not associated with a discernible increase in breast cancer risk.

The effects of recombinant klotho in cisplatin-induced ovarian failure in mice

AIM

To investigate whether recombinant klotho given concomitantly with cisplatin is effective in preventing cisplatin-induced ovarian damage.

METHODS

Thirty-two adult female mice were divided into four groups. Saline was given to the first group, cisplatin to the second group, recombinant mouse klotho to the third group, and recombinant mouse klotho + cisplatin to the fourth group. The removed ovarian tissues were examined and groups were compared histologically and immunohistochemical examination for antimullerian hormone (AMH), superoxide dismutase (SOD) and catalase expression were done. Glutathione peroxidase (GPx) and glutathione reductase (GR) activities were measured by ELISA.

RESULTS

Ovarian tissue weight, primary and secondary follicle counts were higher in cisplatin + recombinant klotho group compared to cisplatin group in our study (respectively p < 0.0001, p < 0.0001, and p = 0.010). Injury scores (stromal congestion, edema and infiltration, follicular degeneration scores and edema in corpus luteum scores) were similar between cisplatin and cisplatin + recombinant klotho groups (all p > 0.05). AMH staining intensities were similar between cisplatin and cisplatin + recombinant klotho groups (p = 0.925). There was no difference between the groups in terms of SOD, GPx, and GR (p > 0.05).

CONCLUSIONS

The recombinant klotho administered before cisplatin could partially protect the ovarian tissue from cisplatin-induced ovarian damage considering that there was no difference in histologic injury score parameters, AMH staining intensity and oxidative stress markers between cisplatin and cisplatin plus klotho groups except that klotho preserved follicules to some extent. The antioxidant mechanism of action of klotho may not be the primary protection mechanism in cisplatin induced ovarian injury.

Splicing alterations in healthy aging and disease

Alternative RNA splicing is a key step in gene expression that allows generation of numerous messenger RNA transcripts encoding proteins of varied functions from the same gene. It is thus a rich source of proteomic and functional diversity. Alterations in alternative RNA splicing are observed both during healthy aging and in a number of human diseases, several of which display premature aging phenotypes or increased incidence with age. Age-associated splicing alterations include differential splicing of genes associated with hallmarks of aging, as well as changes in the levels of core spliceosomal genes and regulatory splicing factors. Here, we review the current known links between alternative RNA splicing, its regulators, healthy biological aging, and diseases associated with aging or aging-like phenotypes. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > Splicing Regulation/Alternative Splicing.

Splicing alterations in healthy aging and disease

Alternative RNA splicing is a key step in gene expression that allows generation of numerous messenger RNA transcripts encoding proteins of varied functions from the same gene. It is thus a rich source of proteomic and functional diversity. Alterations in alternative RNA splicing are observed both during healthy aging and in a number of human diseases, several of which display premature aging phenotypes or increased incidence with age. Age-associated splicing alterations include differential splicing of genes associated with hallmarks of aging, as well as changes in the levels of core spliceosomal genes and regulatory splicing factors. Here, we review the current known links between alternative RNA splicing, its regulators, healthy biological aging, and diseases associated with aging or aging-like phenotypes. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > Splicing Regulation/Alternative Splicing.

Preimplantation genetic testing for carriers of BRCA1/2 pathogenic variants

The detection of germline BRCA1/2 pathogenic variant has relevant implications for the patients and their family members. Family planning, prophylactic surgery and the possibility of preimplantation genetic testing for monogenic disorders (PGT-M) to avoid transmittance of pathogenic variants to the offspring are relevant topics in this setting. PGT-M is valuable option for BRCA carriers, but it remains a controversial and underdiscussed topic. Although the advances in PGT technologies have improved pregnancy rate, there are still several important challenges associated with its use. The purpose of this review is to report the current evidence on PGT-M for BRCA1/2 carriers, ethical concerns and controversy associated with its use, reproductive implications of BRCA pathogenic variants, underlying areas in which an educational effort would be beneficial as well as possibilities for future research efforts in the field.

Anti-HER2/neu Antibody Reduces Chemotherapy-Induced Ovarian Toxicity-From Bench to Bedside

Background: Trastuzumab, a humanized anti-human epidermal growth factor receptor 2 (HER2/neu) antibody, is considered a standard treatment in addition to chemotherapy in the adjuvant setting for HER2/neu-positive breast cancer, yet its impact on fertility and ovarian reserve remains obscure. We aimed to study the effect of anti-HER2/neu on chemotherapy-induced ovarian toxicity in both clinical and preclinical settings. Methods: We prospectively enrolled breast cancer patients below the age of 42 years who were treated with chemotherapy with or without trastuzumab into the study. Anti-Müllerian hormone (AMH) was measured 6 and 12 months post-chemotherapy as an ovarian reserve indicator. In the animal model, pubertal mice were injected with cyclophosphamide or paclitaxel with or without anti-HER2/neu, or saline, and sacrificed 1 week or 3 months later. Ovarian apoptosis, proliferation and vascularity were measured by immunohistochemistry and ovarian reserve was measured by morphometric analysis and serum-AMH. Results: Thirty-three patients with early breast cancer were enrolled into the study. Nineteen patients had HER2/neu negative cancer and were treated with chemotherapy and 14 had HER2/neu positive cancer and were treated with chemotherapy and trastuzumab. In all patients, AMH levels declined to undetectable values immediately post-treatment, but regained for 57.1% of the HER2/neu positive cohort and 36.8% of the negative cohort (p < 0.05). In the preclinical setting, anti-HER2/neu antibody, in combination with chemotherapy, displayed lessened ovarian and vascular damage. Conclusions: Our results indicate that trastuzumab may alleviate chemotherapy-induced ovarian toxicity that may be mediated via its effect on ovarian vasculature.

BRCA-related ATM-mediated DNA double-strand break repair and ovarian aging

BACKGROUND

Oocyte aging has significant clinical consequences, and yet no treatment exists to address the age-related decline in oocyte quality. The lack of progress in the treatment of oocyte aging is due to the fact that the underlying molecular mechanisms are not sufficiently understood. BRCA1 and 2 are involved in homologous DNA recombination and play essential roles in ataxia telangiectasia mutated (ATM)-mediated DNA double-strand break (DSB) repair. A growing body of laboratory, translational and clinical evidence has emerged within the past decade indicating a role for BRCA function and ATM-mediated DNA DSB repair in ovarian aging.

OBJECTIVE AND RATIONALE

Although there are several competing or complementary theories, given the growing evidence tying BRCA function and ATM-mediated DNA DSB repair mechanisms in general to ovarian aging, we performed this review encompassing basic, translational and clinical work to assess the current state of knowledge on the topic. A clear understanding of the mechanisms underlying oocyte aging may result in targeted treatments to preserve ovarian reserve and improve oocyte quality.

SEARCH METHODS

We searched for published articles in the PubMed database containing key words, BRCA, BRCA1, BRCA2, Mutations, Fertility, Ovarian Reserve, Infertility, Mechanisms of Ovarian Aging, Oocyte or Oocyte DNA Repair, in the English-language literature until May 2019. We did not include abstracts or conference proceedings, with the exception of our own.

OUTCOMES

Laboratory studies provided robust and reproducible evidence that BRCA1 function and ATM-mediated DNA DSB repair, in general, weakens with age in oocytes of multiple species including human. In both women with BRCA mutations and BRCA-mutant mice, primordial follicle numbers are reduced and there is accelerated accumulation of DNA DSBs in oocytes. In general, women with BRCA1 mutations have lower ovarian reserves and experience earlier menopause. Laboratory evidence also supports critical role for BRCA1 and other ATM-mediated DNA DSB repair pathway members in meiotic function. When laboratory, translational and clinical evidence is considered together, BRCA-related ATM-mediated DNA DSB repair function emerges as a likely regulator of ovarian aging. Moreover, DNA damage and repair appear to be key features in chemotherapy-induced ovarian aging.

WIDER IMPLICATIONS

The existing data suggest that the BRCA-related ATM-mediated DNA repair pathway is a strong candidate to be a regulator of oocyte aging, and the age-related decline of this pathway likely impairs oocyte health. This knowledge may create an opportunity to develop targeted treatments to reverse or prevent physiological or chemotherapy-induced oocyte aging. On the immediate practical side, women with BRCA or similar mutations may need to be specially counselled for fertility preservation.

The Emerging Key Role of Klotho in the Hypothalamus-Pituitary-Ovarian Axis

The hypothalamus-pituitary-ovary axis is the most important system for regulating female reproductive endocrine function. Its dysfunction would lead to the abnormal secretion of gonadotropin-releasing hormone, follicle-stimulating hormone, or luteinizing hormone, and eventually result in the occurrence of reproductive disease, such as congenital hypogonadotropic hypogonadism, polycystic ovary syndrome, and premature ovarian failure. Recently, an anti-aging gene, Klotho, has gained broad attention in female reproductive diseases. Reports have shown that Klotho is closely correlated to the hypothalamus-pituitary-ovary axis and plays a key role in the development and progression of reproductive diseases. With this issue, we generally review the physiological and pathological role of Klotho in the hypothalamus-pituitary-ovary axis. We also review the underlying mechanisms of Klotho in promoting and preventing female reproductive diseases, which involve the dysfunction of the fibroblast growth factor-Klotho endocrine system, the abnormal signaling regulation of Wnt-β-catenin and insulin-like growth factor-1, the accumulation of oxidative stress, and the inhibition of autophagy, eventually affecting the genesis, development, ovulation, or atresia of follicles. The present review would provide new insights and potential therapeutic target strategies for clinical strategies.

BRCA1/2 genes mutations, ovarian reserve and female reproductive outcomes: a systematic review of the literature

INTRODUCTION

BRCA1 and BRCA2 genes mutations seems to impact female fertility, in addition to increasing the risk of ovarian and breast cancer. Several studies had investigated this issue but data available are still controversial. In order to clarify the role of BRCA1 and BRCA2 mutations in female fertility and ovarian function we carried out a systematic review of the literature with the aim to establish a possible management's strategy of these patients.

EVIDENCE ACQUISITION

A review of current literature regarding BRCA mutation (BRCAm) and fertility was conducted using the PubMed tool to select remarkable articles with the keywords "BRCA1/2 gene," "BRCA1/2 mutation," "anti-Müllerian hormone," "female fertility," "ovarian reserve" and "premature ovarian failure."

EVIDENCE SYNTHESIS

In current literature there are controversial findings about the relation between BRCA genes mutations and lifespan of female reproductive age. Several studies showed an higher risk of premature ovarian insufficiency of BRCAs mutations carriers, according to lower serum AMH level, primordial follicle count, or fewer oocyte yield after ovarian stimulation; on the other hand more recent studies reported not significant differences in serum AMH level or in reproductive outcomes between mutated and non-mutated BRCA patients. For this reason, currently there is not a strict recommendation for routine evaluation of fertility in female carriers of BRCA mutations. Nevertheless, the strong advice to complete childbearing by age 40 and then to undergo a risk-reducing salpingo-oophorectomy and the increased risk of infertility as a result of anticancer treatment in breast cancer BRCAm patients, make the issue of fertility and pregnancy planning in these women worthy of consideration.

CONCLUSIONS

A dedicated counseling to discuss these issues, eventually associated with a personalized assessment of serum AMH or antral follicle count in order to have a panoramic view of ovarian reserve, may be useful in the management of these patients.

Effects of fasting on the expression pattern of FGFs in different skeletal muscle fibre types and sexes in mice

Fibroblast growth factors (FGFs) belong to a large family comprising 22 FGF polypeptides that are widely expressed in tissues. Most of the FGFs can be secreted and involved in the regulation of skeletal muscle function and structure. However, the role of fasting on FGF expression pattern in skeletal muscles remains unknown. In this study, we combined bioinformatics analysis and in vivo studies to explore the effect of 24-h fasting on the expression of Fgfs in slow-twitch soleus and fast-twitch tibialis anterior (TA) muscle from male and female C57BL/6 mice. We found that fasting significantly affected the expression of many Fgfs in mouse skeletal muscle. Furthermore, skeletal muscle fibre type and sex also influenced Fgf expression and response to fasting. We observed that in both male and female mice fasting reduced Fgf6 and Fgf11 in the TA muscle rather than the soleus. Moreover, fasting reduced Fgf8 expression in the soleus and TA muscles in female mice rather than in male mice. Fasting also increased Fgf21 expression in female soleus muscle and female and male plasma. Fasting reduced Fgf2 and Fgf18 expression levels without fibre-type and sex-dependent effects in mice. We further found that fasting decreased the expression of an FGF activation marker gene-Flrt2 in the TA muscle but not in the soleus muscle in both male and female mice. This study revealed the expression profile of Fgfs in different skeletal muscle fibre types and different sexes and provides clues to the interaction between the skeletal muscle and other organs, which deserves future investigations.

Aromatase Inhibitors for Ovarian Stimulation in Patients with Breast Cancer

BACKGROUND

Breast cancer is the most common malignancy diagnosed in women, and its treatment has a high probability of loss of fertility. Oocyte vitrification is the most commonly used technique to preserve fertility before starting oncological treatment. Aromatase inhibitors induce hypoestrogenemia while promoting the release of gonadotropins and constitute an alternative drug for ovarian stimulation in patients with breast cancer.

OBJECTIVE

In this mini-review, we update and describe the current status of aromatase inhibitor use in controlled ovarian stimulation for oocyte vitrification in patients with breast cancer.

RESULTS

Aromatase inhibitors are commonly used in combination with gonadotropins for ovarian stimulation in patients with breast cancer who preserve their fertility through oocyte vitrification. They achieve similar ovarian responses as conventional ovarian stimulation protocols in regards to the number of oocytes, and no additional complications after their use have been reported. Furthermore, aromatase inhibitors seem to be safe not only for offspring, as no more congenital defects occur in newborns from pregnancies achieved after their use, but also for the patients, as no more malignancy recurrence or increased mortality was found in cohort studies.

CONCLUSION

Aromatase inhibitors are elective drugs for ovarian stimulation in patients with breast cancer who decide to preserve their fertility through oocyte vitrification.

Declining BRCA-Mediated DNA Repair in Sperm Aging and its Prevention by Sphingosine-1-Phosphate

Recent data suggest that paternal age can have major impact on reproductive outcomes, and with increased age, there is increased likelihood of chromosomal abnormalities in the sperm. Here, we studied DNA damage and repair as a function of male aging and assessed whether sphingosine-1-phosphate (S1P), a ceramide-induced death inhibitor, can prevent sperm aging by enhancing DNA double-strand breaks (DSB) repair. We observed a significant increase in DNA damage with age and this increase was associated with a decline in the expression of key DNA DSB repair genes in mouse sperm. The haploinsufficiency of BRCA1 male mice sperm showed significantly increased DNA damage and apoptosis, along with decreased chromatin integrity when compared to similar age wild type (WT) mice. Furthermore, haploinsufficiency of BRCA1 male mice had lower sperm count and smaller litter size when crossed with WT females. The resulting embryos had a higher probability of growth arrest and reduced implantation. S1P treatment decreased genotoxic-stress-induced DNA damage in sperm and enhanced the expressions of key DNA repair genes such as BRCA1. Co-treatment with an ATM inhibitor reversed the effects of S1P, implying that the impact of S1P on DNA repair is via the ATM-mediated pathway. Our findings indicate a key role for DNA damage repair mechanism in the maintenance of sperm integrity and suggest that S1P can improve DNA repair in sperm. Further translational studies are warranted to determine the clinical significance of these findings and whether S1P can delay male reproductive aging. There is mounting evidence that sperm quality declines with age, similar to that of the oocyte. However, the reasons behind this decline are poorly understood and there is no medical intervention to improve sperm quality. Our study suggests a strong role for DNA damage repair in maintenance of sperm quality, and for the first time, a potential pharmaceutical approach to prevent sperm aging.

Association of BRCA Mutations and Anti-müllerian Hormone Level in Young Breast Cancer Patients

Background: Several preclinical and clinical studies have suggested that BRCA-mutation carriers may have decreased ovarian reserve. However, data in this area are limited and inconsistent, especially in young breast cancer patients. Objective: This study evaluated the association between BRCA mutation status and serum anti-Müllerian hormone (AMH) level in young, reproductive-aged patients with breast cancer. Materials and Methods: Patients ≤ 40 years of age with breast cancer and who had known BRCA status and baseline serum AMH level at Samsung Medical Center, Seoul, Korea, were considered for inclusion. A total of 52 BRCA mutation carriers (27 BRCA1 and 25 BRCA2) and 264 non-carriers were selected for analyses. The serum level of AMH was compared according to presence of a BRCA mutation, and linear and logistic regression analyses were performed to evaluate the association between BRCA mutation and serum AMH level. Results: No difference was found in clinical characteristics between BRCA-mutation carriers and non-carriers. Subjects with any BRCA mutation had a significantly lower median AMH than those without a mutation (2.60 vs. 3.85 ng/mL, 32% reduction, P = 0.004). Linear regression analysis showed a significant negative association between BRCA mutation and AMH level. In addition, logistic regression demonstrated non-significantly increased odds of mutation carriers having AMH < 1.2 ng/mL. However, no difference was found between BRCA1/2 mutations. Conclusions: Breast cancer patients with BRCA mutation have significantly lower serum AMH level. Fertility preservation should be considered more aggressively in young breast cancer patients with BRCA mutation.

Protective effects of mangafodipir against chemotherapy-induced ovarian damage in mice

BACKGROUND

Given the seriousness of chemotherapy-induced ovarian injury in female cancer patients, the preservation of fertility, including through the use of cryopreservation technology and pharmaceuticals, requires investigation. Previous studies have shown that damage to the ovaries is related to oxidative stress caused by anticancer drugs. Therefore, superoxide dismutase (SOD) may represent a key factor in the pharmacological protection of the ovaries. The aim of our study was to identify the effects of mangafodipir, a manganese chelate and SOD-mimetic, on suppression of apoptosis in granulosa cells and primordial follicle activation induced by anticancer drugs.

METHODS

Cell viability assays using methyltrichlorosilane solutions and immunoblotting for cleaved caspase-3 were performed in in vitro experiments with the simultaneous addition of mangafodipir to human non-luteinized granulosa cell line (HGrC) cultures treated with hydrogen peroxide (H₂O₂), cisplatin, or paclitaxel. Count and morphological analyses of follicles at each developing stage in the ovaries and immunohistochemistry for cleaved caspase-3, Ki67 and 4-hydroxynonenal, a marker for oxidative stress, were also performed using mangafodipir-injected 6-week-old female ICR mice treated with cisplatin or paclitaxel. Further, mangafodipir was injected into 6-week-old female BALB/c mice inoculated with ES-2 to analyze whether mangafodipir inhibits the anti-tumor effects of cisplatin or paclitaxel treatment.

RESULTS

Mangafodipir attenuated apoptosis induced by H₂O₂ and anticancer drugs in vitro. Mangafodipir also decreased the expression of 4-hydroxynonenal and reduced cisplatin- and paclitaxel-induced apoptosis in granulosa cells in vivo. In addition, mangafodipir inhibited the loss of primordial follicles. Tumor xenograft studies in mice showed that mangafodipir did not affect anticancer drug antitumor effects.

CONCLUSIONS

Oxidative stress might be one of the mechanisms of cisplatin- and paclitaxel-induced the loss of primordial follicles. Mangafodipir can reduce cisplatin- and paclitaxel-induced apoptosis in granulosa cells and primordial follicle activation partially via its SOD activity. At the same time, mangafodipir might have other potential mechanisms to inhibit the activation of primordial follicles. Further, mangafodipir attenuated the ovarian damage caused by cisplatin and paclitaxel without affecting their antitumor activities. Mangafodipir, therefore, though its efficacy might be limited, may be a new option for the preservation of fertility during anticancer treatment.