Constitutive activation of mTORC1 signaling induced by biallelic loss-of-function mutations in SZT2 underlies a discernible neurodevelopmental disease

There have been increasing number of reports of SZT2-related neurological diseases, the main symptoms of which are epilepsy, developmental delay, macrocephaly and a dysmorphic corpus callosum. SZT2 functions as a regulator of mechanistic target of rapamycin complex 1 (mTORC1) signaling in cultured human cell lines and mouse tissues. However, it remains to be determined whether mutations in SZT2 in human patients alter mTORC1 signaling. In this study, we aimed to investigate the functional consequence of biallelic SZT2 variants in Epstein-Barr virus-induced lymphoblastoid cell lines (LCLs) established from two patients with a typical SZT2-related neurodevelopmental disease. Increased phosphorylation of S6 kinase and S6 was identified in patient-derived cell lines under amino acid-starved condition, suggestive of constitutive hyperactivation of mTORC1 signaling. This result was validated by constitutive lysosomal localization of mTOR in patients’ LCLs. Furthermore, patients’ LCLs display an excessive response to slight amino acid stimulation. Our data suggest the loss-of-function nature of SZT2 mutations in the patients, and consequent hyperactivation of mTORC1 signaling in response to both amino acid starvation and stimulation in their LCLs. By these functional analyses, the pathogenicity of newly identified SZT2 variants can be determined, allowing for more detailed characterization of genotype-phenotype correlations.

Ral GTPase Activation by Downregulation of RalGAP Enhances Oral Squamous Cell Carcinoma Progression

Ral small GTPases, consisting of RalA and RalB, are members of the Ras family. Their activity is upregulated by RalGEFs. Since several RalGEFs are downstream effectors of Ras, Ral is activated by the oncogenic mutant Ras. Ral is negatively regulated by RalGAP complexes that consist of a catalytic α1 or α2 subunit and its common partner β subunit and similarly regulate the activity of RalA as well as RalB in vitro. Ral plays an important role in the formation and progression of pancreatic and lung cancers. However, the involvement of Ral in oral squamous cell carcinoma (OSCC) is unclear. In this study, we investigated OSCC by focusing on Ral. OSCC cell lines with high Ral activation exhibited higher motility. We showed that knockdown of RalGAPβ increased the activation level of RalA and promoted the migration and invasion of HSC-2 OSCC cells in vitro. In contrast, overexpression of wild-type RalGAPα2 in TSU OSCC cells attenuated the activation level of RalA and inhibited cell migration and invasion. Real-time quantitative polymerase chain reaction analysis of samples from patients with OSCC showed that RalGAPα2 was downregulated in oral cancer tissues as compared with normal epithelia. Among patients with OSCC, those with a lower expression of RalGAPα2 showed a worse overall survival rate. A comparison of DNA methylation and histone modifications of the RalGAPα2 gene in OSCC cell lines suggested that crosstalk among DNA methylation, histone H4Ac, and H3K27me2 was involved in the downregulation of RalGAPα2. Thus, activation of Ral GTPase by downregulation of RalGAP expression via a potential epigenetic mechanism may enhance OSCC progression.

Severity of hot flushes is inversely associated with dietary intake of vitamin B6 and oily fish

Objectives: This study investigated the links between the severity of vasomotor symptoms (VMS) and the dietary consumption of a variety of nutrients. Method: A cross-sectional analysis of the first-visit records of 262 women aged 40-65 years was conducted. The severity of their hot flushes (HF) and night sweats (NS) and their dietary consumption of nutrients were evaluated using the Menopausal Health-Related Quality of Life Questionnaire and the brief-type self-administered Diet History Questionnaire, respectively. The relationships between severity of HF/NS and dietary intake were analyzed separately for 43 major nutrients. We then evaluated different food items as sources of the nutrients. Results: After adjustment for age, body mass index, menopausal status, and background factors significantly related to VMS, only vitamin B₆ (VB₆) was significantly related to severity of HF (adjusted odds ratio per 10 μg/MJ in VB₆ intake, 0.92; 95% confidence interval, 0.86-0.97). Moreover, a significant inverse relationship was found between the consumption of oily fish as a source of VB₆ and the severity of HF. Conclusions: VB₆ and oily fish intake is inversely associated with the severity of HF in middle-aged women. Therefore, increased intake of VB₆ could help attenuate HF.

Elucidation of the pathogenic mechanism and potential treatment strategy for a female patient with spastic paraplegia derived from a single-nucleotide deletion in PLP1

Pelizaeus-Merzbacher disease (PMD) is an X-linked recessive disorder caused by abnormalities in the gene PLP1. Most females harboring heterozygous PLP1 abnormalities are basically asymptomatic. However, as a result of abnormal patterns of X-chromosome inactivation, it is possible for some female carriers to be symptomatic. Whole-exome sequencing of a female patient with unknown spastic paraplegia was performed to obtain a molecular diagnosis. As a result, a de novo heterozygous single-nucleotide deletion in PLP1 [NM_000533.5(PLP1_v001):c.783del; p.Thr262Leufs*20] was identified. RNA sequencing was performed in a patient-derived lymphoblastoid cell line, confirming mono-allelic expression of the mutated allele and abnormal inactivation of the wild-type allele. The patient-derived lymphoblastoid cell line was then treated with VX680 or 5azadC, which resulted in restored expression of the wild-type allele. These two agents thus have the potential to reverse inappropriately-skewed inactivation of the X-chromosome.

Evaluation of the compliance with antiemetic guidelines for prevention of chemotherapy-induced nausea and vomiting in patients with hematologic malignancy

To assess compliance with the Japanese antiemetic guidelines for chemotherapy-induced nausea and vomiting (CINV), the frequencies of CINV occurrence and use of antiemetic rescue medications were examined in patients with hematological malignancy. A total of 40 patients with hematologic malignancy were eligible in this study. This study was performed in the Department of Hematology, Kyushu University Hospital, as a subgroup analysis from a nationwide, multicenter prospective cohort study conducted by the CINV Study Group of Japan. In the patients with hematological malignancy, the guideline compliance rate was 45 %. Five patients (22.7 %) experienced vomiting during the observation period after receiving non-guideline-consistent antiemetic prophylaxis, whereas no patient experienced vomiting after receiving guideline-consistent antiemetic prophylaxis. The study was not sufficiently powered to reach a statistical significance in its frequency of occurrence between the compliance and non-compliance groups. In the entire study period, 8 out of 40 patients required rescue medication, but there was no association between the status of compliance and the antiemetic guidelines. A total of 22 (55.0 %) patients achieved complete response, which was defined as no vomiting and no use of antiemetic rescue medication, during the study period. The rate of compliance with the prophylactic antiemetic treatment guidelines seemed to be low in patients with hematological malignancy, although the status of the guideline compliance did not always influence the antiemetic effects.

Safety and efficacy of nivolumab in combination with S-1/capecitabine plus oxaliplatin in patients with previously untreated, unresectable, advanced, or recurrent gastric/gastroesophageal junction cancer: interim results of a randomized, phase II trial (ATTRACTION-4)

BACKGROUND

Nivolumab is approved as an option for third- or later-line treatment of advanced gastric/gastroesophageal junction (G/GEJ) cancer in several countries after ATTRACTION-2. To further improve the therapeutic efficacy of first-line therapy, exploration of a nivolumab-chemotherapy combination is warranted. In part 1 (phase II) of ATTRACTION-4, the safety and efficacy of nivolumab combined with S-1 plus oxaliplatin (SOX) or capecitabine plus oxaliplatin (CapeOX) as first-line therapy for unresectable advanced or recurrent human epidermal growth factor receptor 2 (HER2)-negative G/GEJ cancer were evaluated.

PATIENTS AND METHODS

Patients were randomized (1 : 1) to receive nivolumab (360 mg intravenously every 3 weeks) plus SOX (S-1, 40 mg/m2 orally twice daily for 14 days followed by 7 days off; oxaliplatin, 130 mg/m2 intravenously on day 1 every 3 weeks) or CapeOX (capecitabine, 1000 mg/m2 orally twice daily for 14 days followed by 7 days off; oxaliplatin, 130 mg/m2 intravenously on day 1 every 3 weeks) until disease progression, unacceptable toxicity, or consent withdrawal.

RESULTS

Of 40 randomized patients, 39 (nivolumab plus SOX, 21; nivolumab plus CapeOX, 18) and 38 (21 and 17, respectively) comprised the safety and efficacy populations, respectively. Most frequent (>10%) grade 3/4 treatment-related adverse events were neutropenia (14.3%) in the nivolumab plus SOX group, and neutropenia (16.7%), anemia, peripheral sensory neuropathy, decreased appetite, type 1 diabetes mellitus, and nausea (11.1% each) in the nivolumab plus CapeOX group. No treatment-related death occurred. Objective response rate was 57.1% (95% confidence interval 34.0-78.2) with nivolumab plus SOX and 76.5% (50.1-93.2) with nivolumab plus CapeOX. Median overall survival was not reached (NR) in both groups. Median progression-free survival was 9.7 months (5.8-NR) and 10.6 months (5.6-12.5), respectively.

CONCLUSION

Nivolumab combined with SOX/CapeOX was well tolerated and demonstrated encouraging efficacy for unresectable advanced or recurrent HER2-negative G/GEJ cancer. ATTRACTION-4 has proceeded to part 2 (phase III) to compare nivolumab plus SOX/CapeOX versus placebo plus SOX/CapeOX.

CLINICALTRIALS.GOV ID

NCT02746796.

Simultaneous measurement of patient dose and distribution of indoor scattered radiation during digital breast tomosynthesis

INTRODUCTION

Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.

METHODS

We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.

RESULTS

We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.

CONCLUSION

By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with metastatic oesophageal cancer: a JSMO-ESMO initiative endorsed by CSCO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of oesophageal cancer was published in 2016, and covered the management and treatment of local/locoregional disease, limited disease, locally advanced disease and the management of advanced/metastatic disease. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting immediately after the JSMO Annual Meeting in 2018. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic oesophageal cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic oesophageal cancer representing the oncological societies of Japan (JSMO), China (CSCO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with metastatic gastric cancer: a JSMO-ESMO initiative endorsed by CSCO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of gastric cancer (GC) was published in 2016, and covered the management and treatment of local, locoregional, locally advanced and metastatic disease. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and The Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting immediately after the JSMO Annual Meeting in 2018. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic GC in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic GC representing the oncological societies of Japan (JSMO), China (CSCO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Catalytic enhancement on Ti–Zr complex oxide particles for electrochemical hydrogenation of oxalic acid to produce an alcoholic compound by controlling electronic states and oxide structures

Ti_0.9Zr_0.1O₂ complex oxide particles exhibit superior catalytic performances for the direct power storage into glycolic acid via electroreduction of oxalic acid due to favorable crystallinity.

MYCN de novo gain-of-function mutation in a patient with a novel megalencephaly syndrome

BACKGROUND

In this study, we aimed to identify the gene abnormality responsible for pathogenicity in an individual with an undiagnosed neurodevelopmental disorder with megalencephaly, ventriculomegaly, hypoplastic corpus callosum, intellectual disability, polydactyly and neuroblastoma. We then explored the underlying molecular mechanism.

METHODS

Trio-based, whole-exome sequencing was performed to identify disease-causing gene mutation. Biochemical and cell biological analyses were carried out to elucidate the pathophysiological significance of the identified gene mutation.

RESULTS

We identified a heterozygous missense mutation (c.173C>T; p.Thr58Met) in the MYCN gene, at the Thr58 phosphorylation site essential for ubiquitination and subsequent MYCN degradation. The mutant MYCN (MYCN-T58M) was non-phosphorylatable at Thr58 and subsequently accumulated in cells and appeared to induce CCND1 and CCND2 expression in neuronal progenitor and stem cells in vitro. Overexpression of Mycn mimicking the p.Thr58Met mutation also promoted neuronal cell proliferation, and affected neuronal cell migration during corticogenesis in mouse embryos.

CONCLUSIONS

We identified a de novo c.173C>T mutation in MYCN which leads to stabilisation and accumulation of the MYCN protein, leading to prolonged CCND1 and CCND2 expression. This may promote neurogenesis in the developing cerebral cortex, leading to megalencephaly. While loss-of-function mutations in MYCN are known to cause Feingold syndrome, this is the first report of a germline gain-of-function mutation in MYCN identified in a patient with a novel megalencephaly syndrome similar to, but distinct from, CCND2-related megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome. The data obtained here provide new insight into the critical role of MYCN in brain development, as well as the consequences of MYCN defects.

Network meta-analysis of the relative efficacy of bariatric surgeries for diabetes remission

BACKGROUND

Bariatric surgery leads to a higher remission rate for type 2 diabetes mellitus than non-surgical treatment. However, it remains unsolved which surgical procedure is the most efficacious. This network meta-analysis aimed to rank surgical procedures in terms of diabetes remission.

METHODS AND FINDINGS

We electronically searched for randomized controlled trials in which at least one surgical treatment was included among multiple arms and the diabetes remission rate was included in study outcomes. A random-effects network meta-analysis was performed within a frequentist framework. The hierarchy of treatments was expressed as the surface under the cumulative ranking curve value. Results of the analysis of 25 eligible randomized controlled trials that covered non-surgical treatments and eight surgical procedures (biliopancreatic diversion [BPD], BPD with duodenal switch, Roux-en Y gastric bypass, mini gastric bypass [mini-GBP], laparoscopic adjustable gastric banding, laparoscopic sleeve gastrectomy, greater curvature plication and duodenal-jejunal bypass) showed that BPD and mini-GBP had the highest surface under the cumulative ranking curve values among the eight surgical treatments.

CONCLUSION

Current network meta-analysis indicated that BPD or mini-GBP achieved higher diabetes remission rates than the other procedures. However, the result needs to be interpreted with caution considering that these procedures were in the minority of bariatric surgeries.

Ultrahigh-Precision Measurement of the n=2 Triplet P Fine Structure of Atomic Helium Using Frequency-Offset Separated Oscillatory Fields

For decades, improved theory and experiment of the n=2 ^{3}P fine structure of helium have allowed for increasingly precise tests of quantum electrodynamics, determinations of the fine-structure constant α, and limitations on possible beyond-the-standard-model physics. Here we use the new frequency-offset separated-oscillatory-fields technique to measure the 2^{3}P_{2}→2^{3}P_{1} interval. Our result of 2 291 176 590(25) Hz represents a major step forward in precision for helium fine-structure measurements.

Longitudinal Findings of MRI and PET in West Syndrome with Subtle Focal Cortical Dysplasia

BACKGROUND AND PURPOSE

Despite the development of neuroimaging, identification of focal cortical dysplasia remains challenging. The purpose of this study was to show the longitudinal changes of MR imaging and FDG-PET in patients with West syndrome and subtle focal cortical dysplasia.

MATERIALS AND METHODS

Among 52 consecutive patients with West syndrome, 4 were diagnosed with subtle focal cortical dysplasia on 3T MR imaging. MR imaging and PET findings were evaluated longitudinally at onset and at 12 and 24 months of age.

RESULTS

At the onset of West syndrome, MR imaging demonstrated focal signal abnormalities of the subcortical white matter in 2 patients. In the other 2 patients, focal subcortical high-intensity signals became visible on follow-up T2WI as myelination progressed. PET at onset showed focal cortical hypometabolism in 3 patients, with 1 of these patients also having focal hypermetabolism and 1 having normal findings. On PET at 24 months, hypometabolism persisted in 2 patients and disappeared in 1, and hypermetabolism disappeared in 1. In 1 patient with normal MR imaging and PET findings at onset, focal hyperintensity and hypometabolism first appeared at 24 months of age. The findings on MR imaging and PET in these patients evolved differently with brain maturation and the clinical course.

CONCLUSIONS

Subtle focal cortical dysplasia can be undetectable on MR imaging at the onset of West syndrome and is not always accompanied by hypometabolism or hypermetabolism on PET. Longitudinal MR imaging and PET studies may be useful for detecting such lesions. Even in West syndrome with a congenital structural abnormality, PET findings evolve differently with brain maturation and the clinical condition.

Layer thickness dependence of the terahertz emission based on spin current in ferromagnetic heterostructures

The emission with a bandwidth of 1.5 terahertz based on the spin current in the ferromagnetic heterostructure Co/Pt is demonstrated. The spin transient launched by the NIR femtosecond laser pulse in the Co/Pt is converted into the in-plane charge current due to the inverse spin Hall effect, which gives rise to the terahertz emission towards free space. The dependence of the terahertz emission on the Pt-layer thickness is investigated. To optimize the geometry structure of the new type of emitter, we developed the theoretical model by carefully analyzing the spin transport. Our model reveals the importance to take into account the interfacial spin loss. It can be used to analyze more complex heterostructures.

Comparison of antiemetic effects of granisetron and palonosetron in patients receiving bendamustine-based chemotherapy

The antiemetic effects and safety of granisetron and palonosetron against chemotherapy-induced nausea and vomiting (CINV) were retrospectively evaluated in patients with non-Hodgkin lymphoma receiving bendamustine-based chemotherapy. A total of 61 patients were eligible for this study. Before starting the bendamustine-based chemotherapy, granisetron or palonosetron were intravenously administered with or without aprepitant and/or dexamethasone. The proportions of patients with complete control (CC) during the overall (during the 6 days after the start of the chemotherapy), acute (up to 2 days), and delayed (3 to 6 days) phases were assessed. CC was defined as complete response with only grade 0-1 nausea, no vomiting, and no use of antiemetic rescue medication. Granisetron or palonosetron alone were administered to 9 and 19 patients, respectively. Aprepitant and/or dexamethasone were combined with granisetron and palonosetron in 28 and 5 patients, respectively. Acute CINV was completely controlled in all patients. Both granisetron monotherapy and palonosetron combination therapy could provide good control of delayed CINV, although the CC rates during the delayed and overall phases were not significantly different among mono- and combination therapy of the antiemetics. There was no significant difference in the frequencies of adverse drug events between the granisetron and palonosetron treatment groups. The present study showed that the antiemetic efficacy and safety of granisetron-based therapy were non-inferior to those of palonosetron-based therapy. Taken together with treatment costs, granisetron monotherapy would be adequate to prevent CINV in patients with non-Hodgkin lymphoma receiving bendamustine-based chemotherapy.

Comparison of pregnancy outcomes following fresh and electively frozen single blastocyst transfer in natural cycle and clomiphene-stimulated IVF cycles

STUDY QUESTION

Are there any differences in live birth rates (LBR) following fresh blastocyst transfer in natural or clomiphene-stimulated cycles, or after elective blastocyst freezing in clomiphene-stimulated cycles followed by thawing and transfer at different time-points?

SUMMARY ANSWER

Clomiphene citrate (CC) administration adversely affected the LBR after single fresh blastocyst transfer (SBT) in CC cycles compared with that in natural cycles, while this adverse effect of CC is not present when a single vitrified-warmed blastocyst transfer (SVBT) is performed in subsequent natural ovulatory cycles, regardless of the duration between CC administration and the day of SVBT.

WHAT IS KNOWN ALREADY

CC affects uterine receptivity associated with a thinning of the uterine endometrium through an antioestrogenic effect. However, the duration that this adverse effect of CC on uterine endometrium persists after initial use is still unknown.

STUDY DESIGN, SIZE, DURATION

A retrospective cohort study of 157 natural cycle IVFs followed by SBT and 1496 minimal ovarian stimulation with CC IVF cycles followed by SBT (n = 24) or SVBT (n = 1472) from January 2010 to December 2014 was conducted. SVBT cycles were classified into two groups according to the period between the last day of CC administration and the day of SVBT (A: ≤60 d and B: ≥61 d). All groups were then compared based on pregnancy outcomes (natural-SBT group: n = 157, CC-SBT group: n = 24, SVBT-A: n = 1143, SVBT-B: n = 329).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women were aged 30–39 years at oocyte retrieval. In SVBT cycles, blastocysts were vitrified and warmed using a Cryotop safety kit. SVBT was performed in subsequent natural ovulatory cycles. The main outcomes were LBR and neonatal outcome, and both were compared among the groups.

MAIN RESULTS AND THE ROLE OF CHANCE

The LBR in the CC-SBT group (29.2%, 7/24) was significantly lower compared with the natural-SBT (56.1%, 88/157) (P = 0.01) and SVBT-A (50.0%, 572/1143) (P = 0.04), but not SVBT-B (47.4%, 156/329), groups. Furthermore, multivariate logistic regression analysis revealed that the LBR was comparable among the natural-SBT and SVBT groups, but was significantly lower in the CC-SBT group (adjusted odds ratio: 0.324, 95% CI: 0.119–0.800, P = 0.01). No significant differences among all groups were observed for gestational age (P = 0.19), birthweight (P = 0.41) and incidence of malformation (P = 0.53).

LIMITATIONS, REASONS FOR CAUTION

In this study we analysed a biased sample, based on clinical judgement regarding endometrial thickness, and the study was limited by its retrospective nature. The low statistical power caused by the group size disparity was also a limitation, especially in the CC-SBT group. Although the outcome showing inferiority of CC-SBT compared to natural-SBT is consistent with general findings in the literature, further large-scale clinical studies, ideally RCTs, are necessary to validate our results and clarify the prolonged effect of CC in SVBT cycles on pregnancy and neonatal outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Our observation suggests that CC administered in minimal ovarian stimulation cycles affects adversely the pregnancy outcomes when SBT is performed. Therefore, for a CC-based minimal stimulation IVF cycle, we suggest that frozen embryo transfer should be performed in a subsequent natural ovulatory cycle to avoid the possibility of implantation failure associated with CC administration.

STUDY FUNDING/COMPETING INTERESTS

The authors have no conflicts of interest to declare. No external funding was either sought or obtained.