Epigenomic control of gonadotrophin‐releasing hormone neurone development and hypogonadotrophic hypogonadism

Mammalian reproductive success depends on gonadotrophin‐releasing hormone (GnRH) neurones to stimulate gonadotrophin secretion from the anterior pituitary and activate gonadal steroidogenesis and gametogenesis. Genetic screening studies in patients diagnosed with Kallmann syndrome (KS), a congenital form of hypogonadotrophic hypogonadism (CHH), identified several causal mutations, including those in the fibroblast growth factor (FGF) system. This signalling pathway regulates neuroendocrine progenitor cell proliferation, fate specification and cell survival. Indeed, the GnRH neurone system was absent or abrogated in transgenic mice with reduced (ie, hypomorphic) Fgf8 and/or Fgf receptor (Fgfr) 1 expression, respectively. Moreover, we found that GnRH neurones were absent in the embryonic olfactory placode of Fgf8 hypomorphic mice, the putative birthplace of GnRH neurones. These observations, together with those made in human KS/CHH patients, indicate that the FGF8/FGFR1 signalling system is a requirement for the ontogenesis of the GnRH neuronal system and function. In this review, we discuss how epigenetic factors control the expression of genes such as Fgf8 that are known to be critical for GnRH neurone ontogenesis, fate specification, and the pathogenesis of KS/CHH.     

Population pharmacokinetics of vactosertib,a new TGF-β receptor type Ι inhibitor,in patients with advanced solid tumors

Cancer Chemotherapy and Pharmacology - Vactosertib, a novel inhibitor of transforming growth factor-β type Ι receptor, is under development for the treatment of various cancers. The...     

Characterization of infections and hypogammaglobulinemia treated with the combination of pertuzumab and trastuzumab

We update a patient series that reported a high incidence of infection with Gram-positive cocci in women treated with the combination of pertuzumab and trastuzumab and further characterize this clinical problem. Treating physicians and advanced practice partners identified women who developed infections while on treatment with pertuzumab and trastuzumab alone or in combination with chemotherapy and enrolled them onto this registry trial. Between March, 2014 and May, 2017, 48 patients with HER2-positive breast cancers were reported to have 59 individual infections. The median age was 48 years. Twenty-four patients received neoadjuvant therapy, 17 were treated for metastatic disease, and 7 were treated in the adjuvant setting. Pertuzumab and trastuzumab were combined with carboplatin and docetaxel in 24 (49%) patients, docetaxel in 10 (21%), nab-paclitaxel in 12 (24%), and without other agents in 2 (4%). Granulocyte growth factors were administered in 24 (49%) patients and no patients were documented to be neutropenic. Folliculitis developed in 25 (52%) patients and was counted as a single infection. Abscesses developed at a number of sites in 24 (49%) patients, including a septic knee requiring total knee replacement. Paronychia occurred in 7 (15%) patients, and 5 (10%) developed cellulitis. When cultures were obtained, Gram-positive cocci were consistently identified. Hypogammaglobulinemia was documented in 14 (36%) of the 33 patients tested. Our data continue to support an increased risk of infections with Gram-positive cocci as a potentially serious adverse event in women treated with pertuzumab and trastuzumab.     

Vitamin E and cancer prevention: Studies with different forms of tocopherols and tocotrienols

α-Tocopherol (α-T) is the major form of vitamin E (VE) in animals and has the highest activity in carrying out the essential antioxidant functions of VE. Because of the involvement of oxidative stress in carcinogenesis, the cancer prevention activity of α-T has been studied extensively. Lower VE intake or nutritional status has been shown to be associated with increased cancer risk, and supplementation of α-T to populations with VE insufficiency has shown beneficial effects in lowering the cancer risk in some intervention studies. However, several large intervention studies with α-T conducted in North America have not demonstrated a cancer prevention effect. More recent studies have centered on the γ- and δ-forms of tocopherols and tocotrienols (T3). In comparison with α-T, these forms have much lower systemic bioavailability but have shown stronger cancer-preventive activities in many studies in animal models and cell lines. γ-T3 and δ-T3 generally have even higher activities than γ-T and δ-T. In this article, we review recent results from human and laboratory studies on the cancer-preventive activities of different forms of tocopherols and tocotrienols, at nutritional and pharmacological levels. We aim to elucidate the possible mechanisms of the preventive actions and discuss the possible application of the available information for human cancer prevention by different VE forms.     

TP53 alterations in relapsed childhood acute lymphoblastic leukemia

TP53 alterations are frequent relapse‐acquired mutations in childhood acute lymphoblastic leukemia (ALL). The present study evaluated the clinical significance of relapsed childhood ALL in Taiwan. Diagnostic and/or relapsed bone marrow or peripheral blood was obtained from 111 children with relapsed ALL who were initially treated by using Taiwan Pediatric Oncology Group (TPOG) ALL protocols from January 1997 to May 2018. Mutations were detected by PCR and sequencing, as well as by multiplex ligation‐dependent probe amplification to detect copy number alterations. Copy number and/or sequence alterations of TP53 were detected in 29% (28 of 98) and in 46% (6 of 13) of patients with relapsed B‐cell and T‐cell ALL, respectively. This incidence was much higher than that in several similar studies conducted in Caucasian populations. Seventy percent of all TP53 alterations were gained at relapse in 67 matched samples by back‐tracking matched diagnostic samples. TP53 alterations were associated with lower 5‐year event‐free survival (EFS) and overall survival (OS) rates (P = .013 and P = .0002, respectively). Multivariate analysis confirmed the prognostic significance of TP53 alterations. Forty‐five patients received hematopoietic stem‐cell transplantations post‐relapse. Patients with TP53 alterations (14/45) had inferior 5‐year EFS and OS than patients without TP53 alterations after transplantation (P = .002 and P = .001, respectively). The significance of these TP53 alterations for patients who received transplantations was confirmed by multivariate analysis. In conclusion, TP53 alterations were enriched and useful as prognostic markers in relapsed childhood ALL.