Emerging treatments for HER2-positive early-stage breast cancer: Focus on neratinib

Over the last decades, a better understanding of breast cancer heterogeneity provided tools for a biologically based personalization of anticancer treatments. In particular, the overexpression of the human epidermal growth factor receptor 2 (HER2) by tumor cells provided a specific target in these HER2-positive tumors. The development of the monoclonal antibody trastuzumab, and its approval in 1998 for the treatment of patients with metastatic disease, radically changed the natural history of this aggressive subtype of breast cancer. These findings provided strong support for the continuous research in targeting the HER2 pathway and implementing the development of new anti-HER2 targeted agents. Besides trastuzumab, a series of other anti-HER2 agents have been developed and are currently being explored for the treatment of breast cancer patients, including those diagnosed with early-stage disease. Among these agents, neratinib, an oral tyrosine kinase inhibitor that irreversibly inhibits HER1, HER2, and HER4 at the intracellular level, has shown promising results, including when administered to patients previously exposed to trastuzumab-based treatment. This article aims to review the available data on the role of the HER2 pathway in breast cancer and on the different targeted agents that have been studied or are currently under development for the treatment of patients with early-stage HER2-positive disease with a particular focus on neratinib

Anti-Müllerian hormone as a marker of ovarian reserve and premature ovarian insufficiency in children and women with cancer: A systematic review

Background: Female patients undergoing anticancer treatment are at elevated risk of adverse ovarian outcomes including infertility and premature ovarian insufficiency (POI), which is associated with short- and long-term health risks. Anti-M\ufcllerian hormone (AMH) is a key biomarker of ovarian reserve, but its role prior to and after cancer treatment is less well understood. Objective and rationale: To conduct a systematic review evaluating AMH as a biomarker of ovarian reserve and POI before and after anticancer treatment, which has become a pressing clinical issue in reproductive medicine. There are a large number of observational studies, but differences in patient groups, cancer diagnoses and study design make this a confusing field that will benefit from a thorough and robust review. Search methods: A systematic literature search for AMH in women with cancer was conducted in PubMed, Embase and Cochrane Central Register of Controlled Trials up to 1 April 2021. Bias review was conducted using the Risk of Bias In Non-randomized Studies of Interventions (ROBINS-I) protocol along with qualitative assessment of quality. Exploratory subgroups were established based on age, cancer type and length of follow-up. Outcomes: Ninety-two publications (N = 9183 patients) were included in this analysis after quality and bias review. Reduced/undetectable AMH was consistently identified in 69/75 studies (92%) following chemotherapy or radiotherapy, with reductions ranging from 42% to concentrations below the limit of detection, and many reporting mean or median declines of 6590%. Where longitudinal data were analysed (42 studies), a majority (33/42 (79%)) of studies reported at least partial recovery of AMH at follow-up, however, effect estimates were highly variable, reflecting that AMH levels were strongly impacted by anticancer treatment (i.e. the chemotherapy regimen used and the number of treatment cycles need), with recovery and its degree determined by treatment regimen, age and pre-treatment AMH level. In 16/31 (52%) publications, oligo/amenorrhoea was associated with lower post-treatment AMH consistent with impending POI, although menstruation and/or pregnancy were reported in patients with low or undetectable AMH. Long-term (>5 years) follow-up of paediatric patients following cancer treatment also found significantly lower AMH compared with control groups in 14/20 (70%) of studies, with very variable effect sizes from complete loss of AMH to full recovery depending on treatment exposure, as in adult patients. Wider implications: AMH can be used to identify the damaging effect of cancer treatments on ovarian function. This can be applied to individual women, including pre-pubertal and adolescent girls, as well as comparing different treatment regimens, ages and pre-treatment AMH levels in populations of women. While there was evidence for its value in the diagnosis of POI after cancer treatment, further studies across a range of diagnoses/treatment regimens and patient ages are required to clarify this, and to quantify its predictive value. A major limitation for the use of AMH clinically is the very limited data relating post-treatment AMH levels to fertility, duration of reproductive lifespan or time to POI; analysis of these clinically relevant outcomes will be important in further research

Diagnostic and predictive accuracy of anti-Mullerian hormone for ovarian function after chemotherapy in premenopausal women with early breast cancer

Funding: This work was undertaken in part in the MRC Centre for Reproductive Health, (supported by MRC grant MR/N022556/1).Purpose Accurate diagnosis and prediction of loss of ovarian function after chemotherapy for premenopausal women with early breast cancer (eBC) is important for future fertility and clinical decisions regarding the need for subsequent adjuvant ovarian suppression. We have investigated the value of anti-mullerian hormone (AMH) as serum biomarker for this. Methods AMH was measured in serial blood samples from 206 premenopausal women aged 40–45 years with eBC, before and at intervals after chemotherapy. The diagnostic accuracy of AMH for loss of ovarian function at 30 months after chemotherapy and the predictive value for that of AMH measurement at 6 months were analysed. Results Undetectable AMH showed a high diagnostic accuracy for absent ovarian function at 30 months with AUROC 0.89 (96% CI 0.84–0.94, P < 0.0001). PPV of undetectable AMH at 6 months for a menopausal estradiol level at 30 months was 0.77. In multivariate analysis age, pre-treatment AMH and FSH, and taxane treatment were significant predictors, and combined with AMH at 6 months, gave AUROC of 0.90 (95% CI 0.86–0.94), with PPV 0.79 for loss of ovarian function at 30 months. Validation by random forest models with 30% data retained gave similar results. Conclusions AMH is a reliable diagnostic test for lack of ovarian function after chemotherapy in women aged 40–45 with eBC. Early analysis of AMH after chemotherapy allows identification of women who will not recover ovarian function with good accuracy. These analyses will help inform treatment decisions regarding adjuvant endocrine therapy in women who were premenopausal before starting chemotherapy.Publisher PDFPeer reviewe

Clinical behavior and outcomes of breast cancer in young women with germline BRCA pathogenic variants

Young breast cancer (BC) patients carrying a germline BRCA pathogenic variant (mBRCA) have similar outcomes as non-carriers. However, the impact of the type of gene (BRCA1 vs. BRCA2) and hormone receptor status (positive [HR+] vs. negative [HR 12]) on clinical behavior and outcomes of mBRCA BC remains largely unknown. This is an international, multicenter, hospital-based, retrospective cohort study that included mBRCA patients diagnosed, between January 2000 and December 2012, with stage I\u2013III invasive early BC at age 6440 years. From 30 centers worldwide, 1236 young mBRCA BC patients were included. Among 808 and 428 patients with mBRCA1 or mBRCA2, 191 (23.6%) and 356 (83.2%) had HR+tumors, respectively (P < 0.001). Median follow-up was 7.9 years. Second primary BC (P = 0.009) and non-BC malignancies (P = 0.02) were more frequent among mBRCA1 patients while distant recurrences were less frequent (P = 0.02). Irrespective of hormone receptor status, mBRCA1 patients had worse disease-free survival (DFS; adjusted HR = 0.76, 95% CI = 0.60\u20130.96), with no difference in distant recurrence-free interval (DRFI) and overall survival (OS). Patients with HR+ disease had more frequent distant recurrences (P < 0.001) and less frequent second primary malignancies (BC: P = 0.005; non-BC: P = 0.18). No differences in DFS and OS were observed according to hormone receptor status, with a tendency for worse DRFI (adjusted HR = 1.39, 95% CI = 0.94\u20132.05) in patients with HR+ BC. Type of mBRCA gene and hormone receptor status strongly impact BC clinical behavior and outcomes in mBRCA young patients. These results provide important information for patients\u2019 counseling on treatment, prevention, and surveillance strategies

Pharmacological and nutritional targeting of voltage-gated sodium channels in the treatment of cancers

International audienc

Alloying ZnS in the hexagonal phase to create high-performing transparent conducting materials

Alloyed zinc sulfide (ZnS) has shown promise as a relatively inexpensive and earth-abundant transparent conducting material (TCM). Though Cu-doped ZnS has been identified as a high-performing p-type TCM, the corresponding n-doped ZnS has, to date, been challenging to synthesize in a controlled manner; this is because the dopant atoms compete with hole-inducing zinc vacancies near the conduction band minimum as the most thermodynamically stable intrinsic point defects. We thus aim to identify the most promising n-type ZnS-based TCM, with the optimal combination of physical stability, transparency, and electrical conductivity. Using a relatively new method for calculating the free energy of both the sphalerite (cubic) and wurtzite (hexagonal) phases of undoped and doped ZnS, we find that doped ZnS is more stable in the hexagonal structure. This, for the first time, fundamentally explains previous experimental observations of the coexistence of both phases in doped ZnS; hence, it profoundly impacts future work on sulfide TCMs. We also employ hybrid density functional theory calculations and a new carrier transport model, AMSET (ab initio model for mobility and Seebeck coefficient using the Boltzmann transport equation), to analyze the defect physics and electron mobility of the different cation- (B, Al, Ga, In) and anion-doped (F, Cl, Br, I) ZnS, in both the cubic and hexagonal phases, at various dopant compositions, temperatures, and carrier concentrations. Among all doped ZnS candidates, Al-doped ZnS (AZS) exhibits the highest dopant solubility, largest electronic band gap, and highest electrical conductivity of 3830, 1905, and 321 S cm(-1), corresponding to the possible carrier concentrations of n = 10(21), 10(20), and 10(19) cm(-3), respectively, at the optimal 6.25% dopant concentration of Al and the temperature of 300 K

Sodium channel current loss of function in induced pluripotent stem cell-derived cardiomyocytes from a Brugada syndrome patient

Brugada syndrome predisposes to sudden death due to disruption of normal cardiac ion channel function, yet our understanding of the underlying cellular mechanisms is incomplete. Commonly used heterologous expression models lack many characteristics of native cardiomyocytes and, in particular, the individual genetic background of a patient. Patient-specific induced pluripotent stem (iPS) cell-derived cardiomyocytes (iPS-CM) may uncover cellular phenotypical characteristics not observed in heterologous models. Our objective was to determine the properties of the sodium current in iPS-CM with a mutation in SCN5A associated with Brugada syndrome. Dermal fibroblasts from a Brugada syndrome patient with a mutation in SCN5A (c.1100G>A, leading to Nav1.5_p.R367H) were reprogrammed to iPS cells. Clones were characterized and differentiated to form beating clusters and sheets. Patient and control iPS-CM were structurally indistinguishable. Sodium current properties of patient and control iPS-CM were compared. These results were contrasted with those obtained in tsA201 cells heterologously expressing sodium channels with the same mutation. Patient-derived iPS-CM showed a 33.1-45.5% reduction in INa density, a shift in both activation and inactivation voltage-dependence curves, and faster recovery from inactivation. Co-expression of wild-type and mutant channels in tsA201 cells did not compromise channel trafficking to the membrane, but resulted in a reduction of 49.8% in sodium current density without affecting any other parameters. Cardiomyocytes derived from iPS cells from a Brugada syndrome patient with a mutation in SCN5A recapitulate the loss of function of sodium channel current associated with this syndrome; including pro-arrhythmic changes in channel function not detected using conventional heterologous expression system

SCN3A ‐related neurodevelopmental disorder: A spectrum of epilepsy and brain malformation

Objective Pathogenic variants in SCN3A , encoding the voltage‐gated sodium channel subunit Nav1.3, cause severe childhood‐onset epilepsy and malformation of cortical development. Here, we define the spectrum of clinical, genetic, and neuroimaging features of SCN3A ‐related neurodevelopmental disorder. Methods Patients were ascertained via an international collaborative network. We compared sodium channels containing wild‐type vs. variant Nav1.3 subunits co‐expressed with β1 and β2 subunits using whole‐cell voltage clamp electrophysiological recordings in a heterologous mammalian system (HEK‐293 T cells). Results Of 22 patients with pathogenic SCN3A variants, most had treatment‐resistant epilepsy beginning in the first year of life (16/21, 76%; median onset, 2 weeks), with severe or profound developmental delay (15/20; 75%). Many, but not all (15/19; 79%), exhibited malformations of cortical development. Pathogenic variants clustered in transmembrane segments 4–6 of domains II‐IV. Most pathogenic missense variants tested (10/11; 91%) displayed gain of channel function, with increased persistent current and/or a leftward shift in the voltage dependence of activation, and all variants associated with malformation of cortical development exhibited gain of channel function. One variant (p.Ile1468Arg) exhibited mixed effects, with gain and partial loss of function. Two variants demonstrated loss of channel function. Interpretation Our study defines SCN3A‐ related neurodevelopmental disorder along a spectrum of severity, but typically including epilepsy and severe or profound developmental delay/intellectual disability. Malformations of cortical development are a characteristic feature of this unusual channelopathy syndrome, present in over 75% of affected individuals. Gain of function at the channel level in developing neurons is likely an important mechanism of disease pathogenesis