Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

A long-term survival case of histiocytic sarcoma by surgery alone in a Japanese elderly breast tumor patient

INTRODUCTION

Histiocytic sarcoma (HS) is a rare hematologic malignancy. HS of the breast is extremely rare, and we present a case of an elderly patient with breast HS.

CASE PRESENTATION

An 81-year-old woman with unremarkable past medical and family histories presented to our hospital with a palpable mass in her right upper breast. She had noticed a mass in her right breast 3 months before her first visit. Physical examination revealed a mass measuring approximately 30 mm in the right upper quadrant of the breast; there were no cervical or axillary lymphadenopathies. Mammography revealed a high-concentration mass with unclear margins in the upper and outer breast. Ultrasound and magnetic resonance imaging (MRI) revealed a 31 × 23-mm nodule with a relatively clear margin and necrotic sign on the T2-intensified image. A mastectomy was performed upon the patient's request, and the surgical specimen revealed a 35-mm hemorrhagic mass. The lesion was estrogen receptor-, progesterone receptor-, and HER2/neu-negative. The Ki-67 labeling index was approximately 30%. The immunohistochemical panel showed immune reactivity for the histiocytic markers CD68, CD163, and CD206 and was immune-negative for B lineage, T lineage, Langerhans cells, and keratins. The diagnosis of HS was based on the morphological and immunophenotypic characteristics of the mass. The patient received no systemic therapy and survived for 50 months without recurrence.

CONCLUSIONS

Here, we report the case of an elderly patient with rare breast HS. Although the prognosis of HS seems poor, the breast HS was not as poor as expected, since it might have been discovered in the local region before it metastasized.

Use of a Baculovirus-Mammalian Cell Expression-System for Expression of Drug-Metabolizing Enzymes: Optimization of Infection With a Focus on Cytochrome P450 3A4

Heterologous expression systems are important for analyzing the effects of genetic factors including single nucleotide polymorphisms on the functions of drug-metabolizing enzymes. In this study, we focused on a baculovirus-mammalian cell (Bac-Mam) expression system as a safer and more efficient approach for this purpose. The baculovirus-insect cell expression system is widely utilized in large-scale protein expression. Baculovirus has been shown to also infect certain mammalian cells, although the virus only replicates in insect cells. With this knowledge, baculovirus is now being applied in a mammalian expression system called the Bac-Mam system wherein a gene-modified baculovirus is used whose promotor is replaced with one that can function in mammalian cells. We subcloned open-reading frames of cytochrome P450 3A4 (CYP3A4), UDP-glucuronosyltransferase (UGT) 1A1, and UGT2B7 into a transfer plasmid for the Bac-Mam system, and prepared recombinant Bac-Mam virus. The obtained virus was amplified in insect Sf9 cells and used to infect mammalian COS-1 cells. Expression of CYP3A4, UGT1A1, and UGT2B7 in COS-1 cell homogenates were confirmed by immunoblotting. Optimum infection conditions including the amount of Bac-Mam virus, culture days before collection, and concentration of sodium butyrate, an enhancer of viral-transduction were determined by monitoring CYP3A4 expression. Expressed CYP3A4 showed appropriate activity without supplying hemin/5-aminolevulinic acid or co-expressing with NADPH-cytochrome P450 reductase. Further, we compared gene transfer efficiency between the Bac-Mam system and an established method using recombinant plasmid and transfection reagent. Our results indicate that the Bac-Mam system can be applied to introduce drug-metabolizing enzyme genes into mammalian cells that are widely used in drug metabolism research. The expressed enzymes are expected to undergo appropriate post-translational modification as they are in mammalian bodies. The Bac-Mam system may thus accelerate pharmacogenetics and pharmacogenomics research.

Changes in Triple-Negative Breast Cancer Molecular Subtypes in Patients Without Pathologic Complete Response After Neoadjuvant Systemic Chemotherapy

PURPOSE

Lehmann et al have identified four molecular subtypes of triple-negative breast cancer (TNBC)-basal-like (BL) 1, BL2, mesenchymal (M), and luminal androgen receptor-and an immunomodulatory (IM) gene expression signature modifier. Our group previously showed that the response of TNBC to neoadjuvant systemic chemotherapy (NST) differs by molecular subtype, but whether NST affects the subtype was unknown. Here, we tested the hypothesis that in patients without pathologic complete response, TNBC subtypes can change after NST. Moreover, in cases with the changed subtype, we determined whether epithelial-to-mesenchymal transition (EMT) had occurred.

MATERIALS AND METHODS

From the Pan-Pacific TNBC Consortium data set containing TNBC patient samples from four countries, we examined 64 formalin-fixed, paraffin-embedded pairs of matched pre- and post-NST tumor samples. The TNBC subtype was determined using the TNBCtype-IM assay. We analyzed a partial EMT gene expression scoring metric using mRNA data.

RESULTS

Of the 64 matched pairs, 36 (56%) showed a change in the TNBC subtype after NST. The most frequent change was from BL1 to M subtypes (38%). No tumors changed from M to BL1. The IM signature was positive in 14 (22%) patients before NST and eight (12.5%) patients after NST. The EMT score increased after NST in 28 (78%) of the 36 patients with the changed subtype (v 39% of the 28 patients without change; P = .002254).

CONCLUSION

We report, to our knowledge, for the first time that the TNBC molecular subtype and IM signature frequently change after NST. Our results also suggest that EMT is promoted by NST. Our findings may lead to innovative adjuvant therapy strategies in TNBC cases with residual tumor after NST.

DAPL1 is a novel regulator of testosterone production in Leydig cells of mouse testis

Leydig cells in the testes produce testosterone in the presence of gonadotropins. Therefore, male testosterone levels must oscillate within a healthy spectrum, given that elevated testosterone levels augment the risk of cardiovascular disorders. We observed that the expression of death-associated protein-like 1 (DAPL1), which is involved in the early stages of epithelial differentiation and apoptosis, is considerably higher in the testes of sexually mature mice than in other tissues. Accordingly, Dapl1-null mice were constructed to evaluate this variation. Notably, in these mice, the testicular levels of steroidogenic acute regulatory protein (StAR) and serum testosterone levels were significantly elevated on postnatal day 49. The findings were confirmed in vitro using I-10 mouse testis-derived tumor cells. The in vivo and in vitro data revealed the DAPL1-regulated the expression of StAR involving altered transcription of critical proteins in the protein kinase A and CREB/CREM pathways in Leydig cells. The collective findings implicate DAPL1 as an important factor for steroidogenesis regulation, and DAPL1 deregulation may be related to high endogenous levels of testosterone.

LAPTM4α is targeted from the Golgi to late endosomes/lysosomes in a manner dependent on the E3 ubiquitin ligase Nedd4-1 and ESCRT proteins

Lysosome-associated protein transmembrane 4α (LAPTM4α) is a four transmembrane-spanning protein primarily localized in endosomes and lysosomes and has several putative lysosomal targeting signals at its C-terminal cytoplasmic domain, including tyrosine-based motifs (YxxΦ) and PY motifs (L/PxxY). LAPTM4α has been previously shown to be ubiquitinated by the E3 ubiquitin ligase Nedd4-1 through binding to its PY motifs and sorted to lysosomes, however, the molecular mechanisms underlying the localization of LAPTM4α to endosomes/lysosomes have not yet been fully elucidated. In the present study, we show that LAPTM4α binds Nedd4-1 in a manner dependent on PY motifs, while the PY motifs and Nedd4-1 are not necessarily required for LAPTM4α ubiquitination. The binding of LAPTM4α with Nedd4-1, however, is necessary for an effective sorting of LAPTM4α from the Golgi to late endosomes/lysosomes. An unexpected finding is that LAPTM4α is localized in the lumen, but not in the limiting membrane, of late endosomes, and degraded in lysosomes over time. Interestingly, we further found that siRNA knockdown of endosomal sorting complexes required for transport (ESCRT) components that mediate sorting of ubiquitinated membrane proteins into intralumenal vesicles (ILVs) of endosomes selectively blocks the transport of LAPTM4α to endosomes. Collectively, these results suggest that trafficking of LAPTM4α from the Golgi to endosomes is promoted by the interaction with Nedd4-1, which further requires ESCRT components. Furthermore, our findings highlight a novel function for ESCRT proteins in mediating protein and/or vesicle trafficking from the Golgi to endosomes/lysosomes.

Ovarian reserve may influence the outcome of bone mineral density in patients with long-term use of dienogest

Objective:

Long-term administration of dienogest, which is known to have effect on bone mineral density, is frequently done in patients with endometriosis and adenomyosis, but a few studies focused on the bone mineral density changes after finishing the long-term therapy. This study aimed to reveal the factors that adversely affect lumbar bone mineral density.

Method:

Fifty-seven premenopausal women who visited our hospital were diagnosed as either endometriosis or adenomyosis, and they were treated by dienogest for more than 115 weeks (26.5 months). Based on a previous report, bone mineral density changes less than 2% was categorized as the osteopenic group ( n = 30), and the others were assigned to the unchanged group ( n = 27). Bone mineral density was measured at the lumbar spine using dual-energy X-ray absorptiometry. A representative ovarian reserve marker, endogenous estradiol levels, and follicle-stimulating hormone levels were measured over time and were compared between the osteopenic and unchanged groups.

Result:

Duration of dienogest intake was 59.5 months (osteopenic group) versus 57.5 months (unchanged group). These patients experienced ovarian surgeries in a similar frequency, but the ovarian reserve in osteopenic group was impaired as suggested by the decline of endogenous estradiol level during intake of dienogest compared to that of unchanged group ( p = 0.0146). Endogenous follicle-stimulating hormone level between osteopenic group and unchanged group did not reach statistically significant difference, although the osteopenic group showed relatively higher level.

Conclusion:

This study might suggest that decreased ovarian reserve as judged by endogenous estradiol level is a factor that negatively affect bone mineral density, and measurement of endogenous estradiol level during intake of dienogest could have a predictive meaning of future decreased bone mineral density level.

Prognostic impacts of prehospital age shock index in patients with acute myocardial infarction

Introduction

Early identification of high-risk patients is the cornerstone of managing patients with acute myocardial infarction (AMI). Age Shock index (ASI; age multiplied by the ratio of heart rate/systolic blood pressure) has been reported to be similar to Global Registry of Acute Coronary Events (GRACE) risk score for predicting mortality in patients with AMI. However, prognostic impacts of prehospital ASI (pre-ASI) in patients with AMI remain unknown.

Methods

We analyzed of 2578 AMI patients who underwent emergency primary percutaneous coronary intervention (PCI) from January 2013 to March 2018, using data from Mie ACS Registry, a prospective and multicenter registry in Japan. Pre-ASI was recorded by emergency medical services at the first contact with the patient before admission, and in-hospital ASI (in-ASI) was recorded prior to PCI at admission. The primary end point was defined as all-cause death.

Results

Median follow-up duration was 753 days (497–838 days). All-cause death was observed in 230 (8.9%) patients. The ROC-AUC (Receiver operating characteristic-area under the curve) of pre-ASI for all- cause death was 0.76 (p&lt;0.001), which was similar to that of in-ASI (0.78, p&lt;0.001) (p=0.25 for pre-ASI versus in-ASI). The cut-off value for pre-ASI and in-ASI was for the prediction of all-cause death was both 45 with a sensitivity of 0.66 and a specificity of 0.78, with a sensitivity of 0.68 and a specificity of 0.76 respectively. According to the Kaplan-Meier survival analysis by combination of pre-ASI≥45 and in-ASI≥45, the patients with pre-ASI≥45 and in-ASI≥45 showed significantly higher all-cause mortality compared to the patients with pre-ASI≥45 and in-ASI&lt;45, the patients with pre-ASI&lt;45 and in-ASI≥45, and the patients with pre-ASI&lt;45 and in-ASI&lt;45 (p&lt;0.001) (Figure). The addition of pre-ASI≥45 to in-ASI≥45 (global chi-squared score: 205) resulted in a significantly increased global chi-squared score, suggesting the incremental prognostic value of pre-ASI (267; p&lt;0.001). Multivariate cox proportional hazard regression analysis for all-cause mortality demonstrated pre-ASI≥45 was a significant independent predictor (HR: 4.86; 95% CI: 3.36 to 7.02, p&lt;0.001). It was strongest predictor compared to left ventricular ejection fraction&lt;40% (HR: 2.45; 95% CI 1.67 to 3.58, p&lt;0.001), hemodialysis (HR: 3.45; 95% CI 1.66 to 7.17, p=0.001), door to balloon time&gt;90 minutes (HR: 1.66; 95% CI 1.18 to 2.34, p=0.004).

Conclusions

High pre-ASI predict increase mortality and assessment of both high pre-ASI and high in-ASI enhance risk stratification in patients with AMI. Early recognizing high pre-ASI may help us make better strategies and improve prognosis for high-risk AMI patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

The carboxyl-terminal di-lysine motif is essential for catalytic activity of UDP-glucuronosyltransferase 1A9

UDP-Glucuronosyltransferase (UGT) is a type I membrane protein localized to the endoplasmic reticulum (ER). UGT has a di-lysine motif (KKXX/KXKXX) in its cytoplasmic domain, which is defined as an ER retention signal. However, our previous study has revealed that UGT2B7, one of the major UGT isoform in human, localizes to the ER in a manner that is independent of this motif. In this study, we focused on another UGT isoform, UGT1A9, and investigated the role of the di-lysine motif in its ER localization, glucuronidation activity, and homo-oligomer formation. Immunofluorescence microscopy indicated that the cytoplasmic domain of UGT1A9 functioned as an ER retention signal in a chimeric protein with CD4, but UGT1A9 itself could localize to the ER in a di-lysine motif-independent manner. In addition, UGT1A9 formed homo-oligomers in the absence of the motif. However, deletion of the di-lysine motif or substitution of lysines in the motif for alanines, severely impaired glucuronidation activity of UGT1A9. This is the first study that re-defines the cytoplasmic di-lysine motif of UGT as an essential peptide for retaining glucuronidation capacity.

Lysosomal integral membrane protein LGP85 (LIMP-2) is ubiquitinated at the N-terminal cytoplasmic domain

LGP85/LIMP-2 is a type III transmembrane glycoprotein of lysosomes, which traverses the membrane twice with an N-terminal uncleaved signal sequence and C-terminal hydrophobic domain. In addition to functioning as a receptor for a lysosomal enzyme β-glucocerebrosidase and for several enteroviruses, LGP85 plays a key role in the biogenesis and maintenance of endosomal/lysosomal compartments (ELCs). Our previous studies have demonstrated that overexpression of rat LGP85 into COS cells results in the enlarged ELCs, from where membrane trafficking is impaired. We show here that rat LGP85 is polyubiquitinated at the N-terminal short cytoplasmic domain that comprises of only three amino acid residues, alanine, arginine, and cysteine. Replacement of either arginine or cysteine with alanine within the N-terminal cytoplasmic domain did not influence the ubiquitination of LGP85, thereby indicating that ubiquitin (Ub) is conjugated to the α-NH2 group of the N-terminal alanine residue. Furthermore, we were able to define a domain necessary for ubiquitination in a region ranging from the amino acids 156 to 255 within the lumenal domain of LGP85. This is the first report showing that the integral lysosomal membrane protein LGP85 is ubiquitinated.

BRCAness as an Important Prognostic Marker in Patients with Triple-Negative Breast Cancer Treated with Neoadjuvant Chemotherapy: A Multicenter Retrospective Study

Triple-negative breast cancer (TNBC) has several subtypes. The identification of markers associated with recurrence and poor prognosis in patients with TNBC is urgently needed. BRCAness is a set of traits in which BRCA1 dysfunction, arising from gene mutation, methylation, or deletion, results in DNA repair deficiency. In the current study, we evaluated the clinical significance and prognosis of BRCAness in a multicenter retrospective study. Ninety-four patients with TNBC treated with neoadjuvant chemotherapy were enrolled from three university hospitals for this retrospective study. BRCAness was evaluated in 94 core needle biopsy (CNB) specimens prior to neoadjuvant chemotherapy and 49 surgical specimens without pathological complete response (pCR). The samples were assessed using multiplex ligation-dependent probe amplification, and the amplicons were scored. Of the 94 patients, 51 had BRCAness in CNB specimens. There were no significant differences in pCR rates or recurrence between the BRCAness and non-BRCAness groups. Among surgical specimens, the BRCAness group had a significantly shorter recurrence-free survival and overall survival compared with the non-BRCAness group. The BRCAness of surgical specimens was found to be an important marker to predict prognosis in patients with TNBC after neoadjuvant chemotherapy. A clinical trial to assess the clinical impact of carboplatin with BRCAness is planned.

The number of FoxP3-positive tumor-infiltrating lymphocytes in patients with synchronous bilateral breast cancer

PURPOSE

In breast cancer, FoxP3-positive tumor-infiltrating lymphocytes (FoxP3+ TILs) vary depending on lymph node status, histological grade, and subtype. All these studies have compared the numbers of FoxP3+ TILs among different hosts, but recruitment of FoxP3+ TILs might depend on each individual's immune environment and each tumor's biological characteristics. In the present study, FoxP3+ TIL numbers were investigated in patients with synchronous bilateral breast cancer (SBBC) to determine the factors that affect FoxP3+ TIL recruitment in the same anti-tumor immune environment.

METHODS

Patients diagnosed with SBBC who underwent curative surgery at two institutions were enrolled in this study. Patients who underwent primary systemic therapy or who were diagnosed with ductal carcinoma in situ or who had distant metastases at diagnosis were excluded. The average numbers of Foxp3+ TILs were determined from the scores of five high-power microscopic fields (HPF). The associations between Foxp3+ TIL numbers and the clinicopathological features of bilateral breasts in a single individual were examined.

RESULTS

Nuclear grade (NG) (p = 0.007) and subtype (p = 0.03), but not size (p = 0.18) and axillary lymph node (p = 0.23) were significantly associated with increase of FoxP3 + TIL numbers by univariate analysis. Further, only NG was a statistically significant clinicopathological factor for change in the number of FoxP3+ TILs by multivariate analysis (p = 0.046) CONCLUSIONS: There was no relationship between FoxP3+ TIL numbers and cancer progression as reflected in tumor size and axillary lymph node in patients with SBBC. Aggressive biological factors, especially high NG, were significantly related to enhanced recruitment of FoxP3+ TILs.

Insulin secretion and sensitivity before and after surgical treatment for aldosterone-producing adenoma

AIM

Primary aldosteronism, which is usually caused by an aldosterone-producing tumour, affects glucose metabolism. The effects of this condition on insulin secretion and insulin sensitivity have remained unclear, however. To gain insight into the influence of primary aldosteronism on glucose tolerance, various parameters related to insulin secretion or insulin sensitivity in patients with an aldosterone-producing tumour were comprehensively analyzed.

METHODS

To assess 14 patients with an aldosterone-producing tumour, hyperglycaemic and hyperinsulinaemic-euglycaemic clamp tests as well as oral glucose tolerance tests (OGTTs) were performed before and after tumour excision. Time between presurgical analysis and surgery was 27-559 (194±132) days, and 14-142 (51±38) days between surgery and postsurgical analysis. Various parameters related to insulin secretion or sensitivity as determined by OGTT as well as hyperglycaemic and hyperinsulinaemic-euglycaemic clamp analyses were evaluated.

RESULTS

Surgical treatment of tumours ameliorated hypokalaemia and reduced plasma aldosterone levels. First and second phases of insulin secretion during the hyperglycaemic clamp, as well as the insulinogenic index and total insulin secretion measured during OGTT, were also improved after surgery. In addition, the insulin sensitivity index determined during the hyperinsulinaemic-euglycaemic clamp was reduced after surgery.

CONCLUSION

Primary aldosteronism impairs insulin secretion.

Investigation of the Endoplasmic Reticulum Localization of UDP-Glucuronosyltransferase 2B7 with Systematic Deletion Mutants

UDP-Glucuronosyltransferase (UGT) plays an important role in the metabolism of endogenous and exogenous compounds. UGT is a type I membrane protein, and has a dilysine motif (KKXX/KXKXX) in its C-terminal cytoplasmic domain. Although a dilysine motif is defined as an endoplasmic reticulum (ER) retrieval signal, it remains a matter of debate whether this motif functions in the ER localization of UGT. To address this issue, we generated systematic deletion mutants of UGT2B7, a major human isoform, and compared their subcellular localizations with that of an ER marker protein calnexin (CNX), using subcellular fractionation and immunofluorescent microscopy. We found that although the dilysine motif functioned as the ER retention signal in a chimera that replaced the cytoplasmic domain of CD4 with that of UGT2B7, UGT2B7 truncated mutants lacking this motif extensively colocalized with CNX, indicating dilysine motif-independent ER retention of UGT2B7. Moreover, deletion of the C-terminal transmembrane and cytoplasmic domains did not affect ER localization of UGT2B7, suggesting that the signal necessary for ER retention of UGT2B7 is present in its luminal domain. Serial deletions of the luminal domain, however, did not affect the ER retention of the mutants. Further, a cytoplasmic and transmembrane domain-deleted mutant of UGT2B7 was localized to the ER without being secreted. These results suggest that UGT2B7 could localize to the ER without any retention signal, and lead to the conclusion that the static localization of UGT results from lack of a signal for export from the ER.

Abstract P4-02-05: Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy

Background: TNBC molecular subtype classification updated by Lehmann et al. includes 4 subtypes: basal-like 1 and 2 (BL1), (BL2), mesenchymal (M), and luminal androgen receptor (LAR), and as a modifier of these subtypes, an Immunomodulatory (IM) gene expression signature. However, molecular subtypes have not been linked to morphological features of TNBC. Apocrine carcinoma has been proposed as a TNBC category that expresses androgen receptor. LAR-subtype TNBC has a poor response to neoadjuvant systemic therapy (NST). We hypothesized that defining the apocrine-featured TNBC by morphology and molecular subtype predict the prognosis of patients with residual disease after NST. Methods: We created the Pan-Pacific TNBC Consortium dataset, which contains paired samples of matched pre and post-NST TNBC tumors from 4 institutions. All patients received NST and didn't have a pathological complete response (pCR). Three pathologists examined hematoxylin and eosin-stained slides of 86 pre-NST samples and determined (1) the presence of apocrine differentiation, (2) the level of tumor-infiltrating lymphocytes (TILs), (3) the histological grade (HG), and (4) the rate of necrosis. These morphological features were compared among the subtypes. For a sample to be considered apocrine positive, apocrine differentiation had to be identified by 2 or more pathologists. Fisher's exact test was used to test the association of subtypes and morphological features. The log-rank test was used to compare disease-free survival (DFS). Results: Twelve of 24 (50%) apocrine-positive tumor samples were LAR subtype, and12 of 17 (70%) LAR-subtype tumor samples exhibited apocrine differentiation. The other subtypes showed following: BL1, 11/44 (25%); BL2, 0/7 (0%); M, 1/10 (10%); unclassified, 0/8 (0%). The median follow-up time was 22 months. In all populations, 2-year DFS rates were higher in patients with apocrine-positive tumors than in those whose tumors did not exhibit apocrine differentiation (P = .027; 2-year DFS, 85% vs 54%). The LAR subtype was also associated with lower HG, although LAR tumors had a similar prognosis to the other subtypes. In the combined analysis of subtypes and apocrine differentiation, patients with apocrine-positive LAR tumors had a higher 2-year DFS rate than did those with apocrine-negative LAR tumors (P = .044; 2-year DFS, 88% vs. 30%). However, patients with apocrine-positive BL1 tumors had no better DFS than did those with apocrine-negative BL1 tumors (P = .133). TIL levels and the presence of the IM signature were positively associated (P = .01), and apocrine differentiation positivity tended to be negatively associated with TIL level (P = .06). Neither TIL level nor IM signature was associated with survival. Conclusion: Apocrine differentiation was associated with the LAR subtype of TNBC and better prognosis in patients who did not have a pCR. The LAR subtype alone did not predict DFS; however, LAR tumors with apocrine differentiation had a better prognosis than did LAR tumors without apocrine differentiation. Using a combination of morphologic and genomic testing may be helpful in determining the prognosis of patients with apocrine-positive TNBC tumors who have residual disease after NST.

Citation Format: Masuda H, Miura S, Harano K, Wang Y, Hirota Y, Matsunaga Y, Lim B, Lucci A, Parinyanitikul N, Lee HJ, Gong G, Rao A, Seitz RS, Morris SW, Hout DR, Nakamura S, Tripathy D, Harada O, Krishnamurthy S, Ueno NT. Apocrine morphology and LAR molecular subtype predict prognosis of TNBC patients with residual disease after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-02-05.

Genetic variations in triple-negative breast cancers undergoing neo-adjuvant chemotherapy

Aim: Triple negative breast cancer (TNBC) is known as aggressive subtype and have no identified targeted therapies. We examined the relationship of neoadjuvant chemotherapy response to genetic variations of TNBC.

Methods: The tumors used in this study were collected from Showa University Hospital, Japan. Thirteen formalin-fixed paraffin-embedded tumors from Japanese TNBC patients who underwent neoadjuvant chemotherapy were used for analysis. Of these, eight surgically resected tumors showed progressive disease and/or recurrence after treatment (PD/REC), and biopsy tissues from five patients showing pathological complete response (pCR) were analyzed. DNA extracted from tissue sample were analyzed. The Miseq system and Trusight Tumor Sequence panel kit were used to sequence 174 amplicons over 82 exons of 26 cancer-related genes to identify genetic mutations.

Results: Seven somatic non-synonymous variants were detected in three genes (FOXL2, PIK3CA, and TP53) in all five pCR patients, and six somatic non-synonymous variants in two genes (PTEN and TP53) were detected in six of eight PD/REC patients. Eight of 13 TNBC tumors were found to have TP53 pathogenic variants, in both pCR and PD/REC cases.

Conclusion: Although TP53 variation was detected in both pCR and PD/REC cases, each location and type of the variant were different. We could not identify genetic mutations associated with chemotherapy response and recurrence.

Raman spectroscopy for the diagnosis of unlabeled and unstained histopathological tissue specimens

AIM

To investigate the possibility of diagnosing gastric cancer from an unstained pathological tissue using Raman spectroscopy, and to compare the findings to those obtained with conventional histopathology.

METHODS

We produced two consecutive tissue specimens from areas with and without cancer lesions in the surgically resected stomach of a patient with gastric cancer. One of the two tissue specimens was stained with hematoxylin and eosin and used as a reference for laser irradiation positioning by the spectroscopic method. The other specimen was left unstained and used for Raman spectroscopy analysis.

RESULTS

A significant Raman scattering spectrum could be obtained at all measurement points. Raman scattering spectrum intensities of 725 cm^-1 and 782 cm^-1, are associated with the nucleotides adenine and cytosine, respectively. The Raman scattering spectrum intensity ratios of 782 cm^-1/620 cm^-1, 782 cm^-1/756 cm^-1, 782 cm^-1/1250 cm^-1, and 782 ​​cm^-1/1263 cm^-1 in the gastric adenocarcinoma tissue were significantly higher than those in the normal stomach tissue.

CONCLUSION

The results of this preliminary experiment suggest the feasibility of our spectroscopic method as a diagnostic tool for gastric cancer using unstained pathological specimens.

Abstract P3-05-17: The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer

Background

Evasion of the immune system is one of the hallmarks of malignant tumors, and recently blocking of such evasion has been used in clinical practice for the treatment of some types of cancers. Recruitment of regulatory T cells (Tregs), which express the specific marker Foxp3, is an established mechanism of escaping from the immune system. In breast cancer, it has been reported that the number of Tregs differs widely among breast cancer subtypes, and that patients who have many Tregs around the tumor tend to have a poor prognosis. However, the factors that are important for the recruitment of Tregs are not well known. Thus, factors that depend on the host (e.g., age or comorbidity), on the tumor (e.g., subtype, grade, or stage), or on measurement error might be the cause of the observed differences in the number of Tregs. In this study, we investigated the numbers of Tregs in simultaneous bilateral breast cancer patients in order to determine the factors that influence the recruitment of Tregs, while excluding differences in individuals as much as possible.

Material and methods

Patients who had breast cancer in both breasts and who underwent simultaneous surgery between January 2005 and September 2015 at two institutions were enrolled in this study. Patients who underwent primary systemic therapy who were diagnosed with ductal carcinoma in situ, or who were stage IV were excluded. The average numbers of Foxp3-positive (Foxp3+cells) were determined from scores of five high-power fields (HPFs). The association between the difference in Foxp3+ cell number between each breast in a single individual and clinicopathological features was examined.

Results

Seventy patients were included in this study. Their ages ranged from 39-85 (median 54) years old. Ninety five percent of the tumors were invasive ductal carcinoma non-special type. Eighty eight (62.9%), 43 (30.7%), and 9 (6.4%) of the tumors were T1, T2, and ≥T3, respectively, and 102 (72.9%) of the tumors were node-negative. Regarding nuclear grade (NG), 104 (74.3%), 21 (22.1%), and 7 (5%) of the tumors were NG1, 2, and 3, respectively. As for subtype, 124 (88.6%), 9 (6.4%), and 7 (5%) were ER-positive and HER2-negative(ER+/HER2-), ER-positive or negative and HER2-negative(ER±/HER2+), and ER-negative and HER2-negative(ER-/HER2-), respectively. The numbers of Foxp3+ cells ranged from 0 to 39.8 (median 3.3)/HPF, and difference in Foxp3+ cell number between each breast in a single individual ranged from 0 to 34 (median 3.9)/HPF.

Differences in tumor size and node status in individuals did not impact on the number of Foxp3+ cells. However, the number of Foxp3+ cells in tumors that were NG3 (P=0.00098) or ER±/HER2+ or ER-/HER2- type (P=0.00586) were statistically significantly increased compared with tumors that were NG1/2 or ER+/HER2- type in the same host.

Furthermore, the difference of Foxp3+ cells between each tumor in a single individual were quite small regarding tumor size and node status in 53 patients who had similar NG and subtype tumors in both breasts.

Conclusions

The number of Foxp3+ cells showed no relationship with tumor size, or lymph node status in simultaneous bilateral breast cancer patients. High NG, ER±/HER2+ or ER-/HER2- type of the tumor were involved with enhancement of the recruitment of Tregs.

Citation Format: Goto R, Hirota Y, Aruga T, Horiguchi S, Tazawa S, Nakamura S, Takimoto M. The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-05-17.

Abstract P4-01-09: γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) is promising fluorescence probe for rapid diagnosis of breast cancer; - The feasibility study of real time imaging for breast cancer examination -

【Background and Aim】

To date, fluorescence imaging has been used gradually for real time diagnosis in various clinical situations. Evaluation of margin on surgical specimens is essential to decide whether additional resection should be performed for breast cancer surgery. In the same context, rapid assessment of biopsy specimen is crucial because when they do not contain any part of the lesions, re-examination should be need.

A fluorescence probe named γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) was rapidly activated by an enzyme, γ-glutamyltransferase (GGT). It was overexpressed in variety of cancers so promising for clinical use. The aim of this study is to examine the usefulness of the probe for breast cancer detection.

【Material and Methods】

We investigated the patients of breast cancer or benign disease who received examination consecutively from March 2015 to February 2016 in our hospital. The samples were obtained by core needle biopsy (CNB) or vacuum-assisted breast biopsy (VAB).We sprayed the probe on these samples immediately after examination and shoot images by CCD camera. To evaluate the fluorescence intensity along the time, we used a filtered CCD camera that could detect specifically gGlu-HMRG color (Discovery® INDEC Medical Systems Inc.). The images were automatically obtained every 30 seconds for 10 minutes after adding the probe on the specimens.

The average value of the image in each region of interest (ROI) was analyzed using image analysis program Image J (https://imagej.nih.gov/ij/).

We investigated the change of fluorescence intensity with the passage of time. We also compared the fluorescence intensity of malignant lesions with benign ones, and analyzed whether the fluorescence intensity could distinguish the malignant lesions from benign ones.

【Result】

We obtained 362 samples from96 tumors. Fifty-six tumors with 215 samples were benign, while 40 tumors with 147samples are malignant histologically.

The fluorescence was immediately observed after sprayed the probe. The intensity had been increasing in proportion to time. The malignant specimens were rapidly increasing; in contrast, the benign ones were slowly. For example, when it took 60 seconds after spraying the probe that the intensity increase up to some level in malignant specimens, while benign one took 240 seconds up to the same level on average.

Comparing the malignant lesions with benign ones after sprayed 120 seconds, the fluorescence intensity was higher in malignant specimens than benign ones (average fluorescence intensity; benign 0.9, malignant 2.3 p=0.0138). By ROC analysis whether the fluorescence intensity could distinguish the malignant lesions from benign, AUC, sensitivity and specificity was 0.63, 70% and 57%, respectively (cut off 0.2).

【Conclusion】

The probe was contributory to distinguish malignant and benign lesions and may be useful for the rapid diagnosis of CNB in practice. We are now trying to seek a more accurate probe to differentiate benign and malignant lesion as a next step.

Citation Format: Takamaru T, Akashi ST, Kuwayama T, Sawada T, Hirota Y, Urano Y, Nakamura S. γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) is promising fluorescence probe for rapid diagnosis of breast cancer; - The feasibility study of real time imaging for breast cancer examination - [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-09.

Decreased Perfusion in Myocardial Region of Normal Donor Artery Secondary to Collateral Development

Thirty-one patients suffering from single vessel exertional angina with collaterals (Group A) were evaluated by stress 201T1 myocardial emission CT (T1-SPECT) with 16 controls of severely stenotic single vessel exertional angina without collaterals (Group B). Group A included 21 patients (68%) who showed an extensive perfusion defect in double artery myocardial regions, including the normal donor artery myocardial region (DMR). However, there were no such cases in Group B, giving a significant difference between these 2 groups (p < 0.001). Four patients in Group A, having a perfusion defect both in DMR and in the collateral dependent myocardial region (CMR) underwent a successful percutaneous transluminal coronary angioplasty (PTCA) with disappearance of collaterals. T1-SPECT findings after PTCA showed no perfusion defect either in CMR or in DMR. This has been explained on the basis that the coronary collaterals stole blood and produced perfusion defect in DMR.

Mitophagy is primarily due to alternative autophagy and requires the MAPK1 and MAPK14 signaling pathways

In cultured cells, not many mitochondria are degraded by mitophagy induced by physiological cellular stress. We observed mitophagy in HeLa cells using a method that relies on the pH-sensitive fluorescent protein Keima. With this approach, we found that mitophagy was barely induced by carbonyl cyanide m-chlorophenyl hydrazone treatment, which is widely used as an inducer of PARK2/Parkin-related mitophagy, whereas a small but modest amount of mitochondria were degraded by mitophagy under conditions of starvation or hypoxia. Mitophagy induced by starvation or hypoxia was marginally suppressed by knockdown of ATG7 and ATG12, or MAP1LC3B, which are essential for conventional macroautophagy. In addition, mitophagy was efficiently induced in Atg5 knockout mouse embryonic fibroblasts. However, knockdown of RAB9A and RAB9B, which are essential for alternative autophagy, but not conventional macroautophagy, severely suppressed mitophagy. Finally, we found that the MAPKs MAPK1/ERK2 and MAPK14/p38 were required for mitophagy. Based on these findings, we conclude that mitophagy in mammalian cells predominantly occurs through an alternative autophagy pathway, requiring the MAPK1 and MAPK14 signaling pathways.

Intracellular Dynamics and Fate of a Humanized Anti-Interleukin-6 Receptor Monoclonal Antibody, Tocilizumab

Tocilizumab (TCZ), a humanized anti-interleukin-6 (IL-6) receptor (IL-6R) monoclonal antibody, abrogates signal transducer protein gp130-mediated IL-6 signaling by competitively inhibiting the binding of IL-6 to the receptor, and shows clinical efficacy in autoimmune and inflammatory diseases. Despite accumulating evidence for therapeutic efficacy, the behavior and fate of TCZ at the cellular level remain largely unknown. To address this, we evaluated the endocytosis and intracellular trafficking of IL-6R in HeLa cells. The results of our study provide evidence that IL-6R is constitutively internalized from the cell surface by ligand or TCZ binding and the expression of gp130 in an independent manner and is targeted via endosomes without being significantly directed to the recycling pathway to, and degraded in, lysosomes. Furthermore, the cytoplasmic tail of IL-6R is required for constitutive endocytosis of the receptor, which is mediated by the clathrin and AP-2 complex. We further demonstrate that FcRn, whose function is to regulate the serum persistence of IgG, is confined primarily to early/recycling endosomes and rapidly transits between these compartments and late endosomes/lysosomes without being degraded. Importantly, the expression of FcRn induces the segregation of TCZ from IL-6R, resulting in extensive colocalization of TCZ and FcRn in IL-6R-depleted endosomal compartments. Collectively, our results suggest that FcRn can accelerate the retrieval of the internalized TCZ, not only from endosomes but also from lysosomes. Our findings provide new insight into the mechanism by which the antibody internalized into cells is rescued from lysosomal degradation and into how its serum levels are maintained.

Ultrastructural and immunohistochemical studies on myocardial biopsies from a patient with eosinophilic endomyocarditis

Right ventricular endomyocardial biopsy specimens from a 13-year-old boy with hypereosinophilia were studied by light and electron microscopy using the EG2 monoclonal antibody, which recognizes a common epitope of eosinophil cationic protein and eosinophil protein-X. Although the endocardial layer was of normal thickness, many eosinophils, mononuclear cells, and free eosinophil granules were observed in the endocardium and in the vicinity of degenerated myocardial cells. Under electron microscopy, many of the specific granules in and out of eosinophils had lost their crystalloid internae and displayed reversed density, and there were many degranulated eosinophils with reduced number of granules. Immunohistochemically, large amounts of eosinophil cationic protein and protein-X were observed within cardiocytes when many of them were degenerated. Deposits of the proteins were also found in some small vessels. On electron microscopy, accumulations of gold particles, which bind to eosinophil cationic protein and protein-X, were seen in association with specific granules and on the myofilaments in both degenerated and normal-appearing cardiocytes. The presence of eosinophil cationic proteins within cardiocytes may play an important role in the pathogenesis of eosinophilic endomyocardial disease.

IQ is an independent predictor of glycated haemoglobin level in young and middle-aged adults with intellectual disability

AIMS

Here we examined whether intellectual disability is independently associated with hyperglycaemia.

METHODS

We recruited 233 consecutive young and middle-aged adults with intellectual disability. After exclusion of subjects on medication for metabolic diseases or with severe intellectual disability (IQ < 35), 121 subjects were divided by IQ into a group with moderate intellectual disability (35 ≤ IQ ≤ 50), a mild intellectual disability group (51 ≤ IQ ≤ 70) and a borderline group (IQ > 70).

RESULTS

HbA1c level was higher in subjects with moderate intellectual disability (42 ± 9 mmol/mol; 6.0 ± 0.8%) than those in the borderline group (36 ± 4 mmol/mol; 5.5 ± 0.3%) and mild intellectual disability group (37 ± 5 mmol/mol; 5.5 ± 0.5%) groups. HbA1c level was correlated with age, BMI, blood pressure, serum triglycerides and IQ in simple linear regression analysis. Multiple regression analysis indicated that IQ, age, BMI and diastolic blood pressure were independent explanatory factors of HbA1c level.

CONCLUSIONS

An unfavourable effect of intellectual disability on lifestyle and untoward effect of hyperglycaemia on cognitive function may underlie the association of low IQ with hyperglycaemia.

Tor and the Sin3-Rpd3 complex regulate expression of the mitophagy receptor protein Atg32 in yeast

When mitophagy is induced in Saccharomyces cerevisiae, the mitochondrial outer membrane protein ScAtg32 interacts with the cytosolic adaptor protein ScAtg11. ScAtg11 then delivers the mitochondria to the pre-autophagosomal structure for autophagic degradation. Despite the importance of ScAtg32 for mitophagy, the expression and functional regulation of ScAtg32 are poorly understood. In this study, we identified and characterized the ScAtg32 homolog in Pichia pastoris (PpAtg32). Interestingly, we found that PpAtg32 was barely expressed before induction of mitophagy and was rapidly expressed after induction of mitophagy by starvation. Additionally, PpAtg32 was phosphorylated when mitophagy was induced. We found that PpAtg32 expression was suppressed by Tor and the downstream PpSin3-PpRpd3 complex. Inhibition of Tor by rapamycin induced PpAtg32 expression, but could neither phosphorylate PpAtg32 nor induce mitophagy. Based on these findings, we conclude that the Tor and PpSin3-PpRpd3 pathway regulates PpAtg32 expression, but not PpAtg32 phosphorylation.

Age-related disruption of autophagy in dermal fibroblasts modulates extracellular matrix components

Autophagy is an intracellular degradative system that is believed to be involved in the aging process. The contribution of autophagy to age-related changes in the human skin is unclear. In this study, we examined the relationship between autophagy and skin aging. Transmission electron microscopy and immunofluorescence microscopy analyses of skin tissue and cultured dermal fibroblasts derived from women of different ages revealed an increase in the number of nascent double-membrane autophagosomes with age. Western blot analysis showed that the amount of LC3-II, a form associated with autophagic vacuolar membranes, was significantly increased in aged dermal fibroblasts compared with that in young dermal fibroblasts. Aged dermal fibroblasts were minimally affected by inhibition of autophagic activity. Although lipofuscin autofluorescence was elevated in aged dermal fibroblasts, the expression of Beclin-1 and Atg5-genes essential for autophagosome formation-was similar between young and aged dermal fibroblasts, suggesting that the increase of autophagosomes in aged dermal fibroblasts was due to impaired autophagic flux rather than an increase in autophagosome formation. Treatment of young dermal fibroblasts with lysosomal protease inhibitors, which mimic the condition of aged dermal fibroblasts with reduced autophagic activity, altered the fibroblast content of type I procollagen, hyaluronan and elastin, and caused a breakdown of collagen fibrils. Collectively, these findings suggest that the autophagy pathway is impaired in aged dermal fibroblasts, which leads to deterioration of dermal integrity and skin fragility.

Casein kinase 2 is essential for mitophagy

Mitophagy is a process that selectively degrades mitochondria. When mitophagy is induced in yeast, the mitochondrial outer membrane protein Atg32 is phosphorylated, interacts with the adaptor protein Atg11 and is recruited into the vacuole with mitochondria. We screened kinase-deleted yeast strains and found that CK2 is essential for Atg32 phosphorylation, Atg32-Atg11 interaction and mitophagy. Inhibition of CK2 specifically blocks mitophagy, but not macroautophagy, pexophagy or the Cvt pathway. In vitro, CK2 phosphorylates Atg32 at serine 114 and serine 119. We conclude that CK2 regulates mitophagy by directly phosphorylating Atg32.

The effect of alcohol intake and the use of oral corticosteroids on the risk of idiopathic osteonecrosis of the femoral head

The systemic use of steroids and habitual alcohol intake are two major causative factors in the development of idiopathic osteonecrosis of the femoral head (ONFH). To examine any interaction between oral corticosteroid use and alcohol intake on the risk of ONFH, we conducted a hospital-based case-control study of 71 cases with ONFH (mean age 45 years (20 to 79)) and 227 matched controls (mean age 47 years (18 to 79)). Alcohol intake was positively associated with ONFH among all subjects: the adjusted odds ratio (OR) of subjects with ≥ 3032 drink-years was 3.93 (95% confidence interval (CI) 1.18 to 13.1) compared with never-drinkers. When stratified by steroid use, the OR of such drinkers was 11.1 (95% CI 1.30 to 95.5) among those who had never used steroids, but 1.10 (95% CI 0.21 to 4.79) among those who had. When we assessed any interaction based on a two-by-two table of alcohol and steroid use, the OR of those non-drinkers who did use steroids was markedly elevated (OR 31.5) compared with users of neither. However, no further increase in OR was noted for the effect of using both (OR 31.6). We detected neither a multiplicative nor an additive interaction (p for multiplicative interaction 0.19; synergy index 0.95), suggesting that the added effect of alcohol may be trivial compared with the overwhelming effect of steroids in the development of ONFH.

Cite this article: Bone Joint J 2013;95-B:320–5.

Parental employment, income, education and allergic disorders in children: a prebirth cohort study in Japan

SETTING

Epidemiological evidence on the relationship between socio-economic status and allergic disorders has been inconsistent.

OBJECTIVES

We examined the associations between maternal employment, maternal job type, household income, and paternal and maternal educational levels and the risk of allergic disorders in Japanese children aged 4.5 years.

DESIGN

Subjects were 480 mother-child pairs. Definitions of wheeze and eczema symptoms were based on criteria of the International Study of Asthma and Allergies in Childhood. Data on self-reported doctor-diagnosed asthma and atopic eczema were available.

RESULTS

Compared with children whose mothers had received less than 13 years of education, those with mothers with ≥15 years of education had a significantly increased risk of wheeze and doctor-diagnosed asthma: the adjusted ORs were respectively 2.41 (95%CI 1.18-5.17) and 2.70 (95%CI 1.03-8.08). Fifteen years or more of paternal education was independently associated with an increased risk of eczema, but not of doctor-diagnosed atopic eczema (adjusted OR 1.89, 95%CI 1.07-3.42). Mother's employment, mother's job type and household income were not related to any of the outcomes.

CONCLUSIONS

Higher maternal educational level may increase the risk of wheeze and asthma, while higher paternal educational level may increase the risk of eczema.

Mitophagy plays an essential role in reducing mitochondrial production of reactive oxygen species and mutation of mitochondrial DNA by maintaining mitochondrial quantity and quality in yeast

In mammalian cells, the autophagy-dependent degradation of mitochondria (mitophagy) is thought to maintain mitochondrial quality by eliminating damaged mitochondria. However, the physiological importance of mitophagy has not been clarified in yeast. Here, we investigated the physiological role of mitophagy in yeast using mitophagy-deficient atg32- or atg11-knock-out cells. When wild-type yeast cells in respiratory growth encounter nitrogen starvation, mitophagy is initiated, excess mitochondria are degraded, and reactive oxygen species (ROS) production from mitochondria is suppressed; as a result, the mitochondria escape oxidative damage. On the other hand, in nitrogen-starved mitophagy-deficient yeast, excess mitochondria are not degraded and the undegraded mitochondria spontaneously age and produce surplus ROS. The surplus ROS damage the mitochondria themselves and the damaged mitochondria produce more ROS in a vicious circle, ultimately leading to mitochondrial DNA deletion and the so-called "petite-mutant" phenotype. Cells strictly regulate mitochondrial quantity and quality because mitochondria produce both necessary energy and harmful ROS. Mitophagy contributes to this process by eliminating the mitochondria to a basal level to fulfill cellular energy requirements and preventing excess ROS production.

Dietary patterns and risk of Parkinson's disease: a case-control study in Japan

BACKGROUND

Nearly all epidemiologic studies examining the association between the risk of Parkinson's disease (PD) and diet have focused on single foods and specific nutrients. However, epidemiologic evidence for the association of dietary pattern with PD, namely the measurement of overall diet by considering the cumulative effects of nutrients is extremely limited. We conducted a hospital-based case-control study in Japan to examine the relationship between dietary patterns and the risk of PD.

METHODS

Patients with PD diagnosed using the UK PD Society Brain Bank criteria (n = 249) and controls without neurodegenerative diseases (n = 368) were recruited. At the time of recruitment, dietary intake during the preceding 1 month was assessed using a validated, self-administered diet history questionnaire. Dietary patterns from 33 predefined food groups (energy-adjusted food g/day) were extracted by factor analysis.

RESULTS

Three dietary patterns were identified: 'Healthy', 'Western' and 'Light meal' patterns. After adjustment for potential non-dietary confounding factors, the Healthy pattern, characterized by a high intake of vegetables, seaweed, pulses, mushrooms, fruits and fish, was inversely associated with the risk of PD with a border-line significance (P for trend = 0.06). Multivariate Odds ratio (95% confidence intervals) for PD in the highest quartile of the Healthy pattern was 0.54 (0.32-0.92) compared with the lowest quartile. No associations with PD were detected for the other two dietary patterns.

CONCLUSION

In this case-control study in Japan, a dietary pattern consisting of high intakes of vegetables, fruits and fish may be associated with a decreased risk of PD.