Alpha-crystallin B chains enhance cell migration in basal-like 2 triple-negative breast cancer cells

Triple-negative breast cancer (TNBC) can be divided into six subtypes. Among these subtypes, the basal-like 2 (BL2) subtype shows the lowest five-year survival rate and highest risk of metastasis. Alpha-crystallin B chains (αB-crystallin), a small heat shock protein that is known to be involved in breast cancer metastasis, is highly expressed in the basal-like subtype but not in the other non-basal subtypes. Thus, we hypothesized that αB-crystallin may be an important factor involved in the worse prognosis of the BL2 subtype compared with those of the other TNBC subtypes. Here, we examined the role of αB-crystallin in cell motility in two TNBC cell lines: HCC1806 (BL2 subtype) and, as control, MDA-MB-436 (mesenchymal stem-like subtype). HCC1806 showed greater cell migration capacity and a higher expression level of the gene encoding αB-crystallin (CRYAB) than did MDA-MB-436. Short interfering RNA-mediated silencing of CRYAB expression significantly reduced the cell migration capacity of HCC1806 cells, whereas it had no effect in MDA-MB-436 cells, indicating that αB-crystallin is essential for the migration of HCC1806 cells. Thus, high αB-crystallin expression may be a contributing factor to the poor prognosis of BL2 TNBC.

Progesterone receptor membrane component 2 expression leads to erlotinib resistance in lung adenocarcinoma cells

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) provide a favorable treatment outcome in patients with EGFR mutation-positive non-small cell lung cancer. However, most of such patients become resistant to EGFR-TKIs within a year. Thus, clarifying the mechanism of acquired resistance to EGFR-TKIs has been a research focus. Here, we demonstrated that the expression of progesterone receptor membrane component 2 (PGRMC2) was upregulated in an erlotinib-resistant cell line, PC9/ER, compared with the parental PC9 lung cancer cells. Our previous study showed that PGRMC1 is responsible for acquired resistance to erlotinib; however, PGRMC2 has not been discussed yet. Thus, the aim of this study was to determine the role of PGRMC2 in acquired resistance to erlotinib. Transfection with PGRMC2 siRNA significantly enhanced the sensitivity to erlotinib in PC9/ER cells. Furthermore, knockdown of PGRMC2 reduced the expression of p21, which is known as cell-cycle inhibitor and antiproliferative effector. These results suggest that PGRMC2 partially contributes to erlotinib resistance in PC9/ER cells, and that investigation into the effect of PGRMC2 on apoptosis and the cell cycle are warranted.

Ephrin type-A receptor 2 on tumor-derived exosomes enhances angiogenesis through the activation of MAPK signaling

Exosomes are potent players in the development of metastases and they play an important role in cancer angiogenesis and exacerbation. However, it is unclear how proteins on exosomes affect development of blood vessel networks. In this study, we focused on relationships between membrane proteins on exosomes and angiogenesis using human umbilical vein endothelial cells (HUVEC). Lung tumor cell-derived exosomes induced tube formation and growth of endothelial cells in vitro in a dose-dependent manner involving MAPK activation, but this was not seen in normal lung epithelial cells. Ephrin type-A receptor 2 (EphA2) was identified by proteomic analysis and an inhibition assays showed it is a major MAPK activator on exosomes. Thus EphA2 on exosomes participates in angiogenesis as a ligand of the ephrin signaling pathway. These results support the development of novel therapeutic strategies such as blockade of remote cancer communications through exosomes.

Gene Polymorphism of Tacrolimus-Metabolizing Enzymes Associated With Impaired Absorption of Tacrolimus Following Allogeneic Hematopoietic Stem Cell Transplantation: A Case Report

OBJECTIVE

To elucidate the mechanisms by which orally administered tacrolimus was not absorbed in a patient following allogeneic hematopoietic stem cell transplantation.

CLINICAL COURSE

A 17-year-old girl with acute myeloid leukemia underwent HLA-haploidentical peripheral blood stem cell transplantation following fludarabine, busulfan, and total-body irradiation. Graft-vs-host disease prophylaxis was post-transplant cyclophosphamide, followed by intravenous tacrolimus and mycophenolate mofetil. When tacrolimus was switched to oral administration, its blood level declined rapidly, resulting in development of acute graft-vs-host disease, which was ameliorated by switching back to intravenous administration.

METHODS/RESULTS

To elucidate if impaired tacrolimus absorption could be related to genetic polymorphism of tacrolimus-metabolizing enzymes, we analyzed gene polymorphisms of cytochrome P450 3A4, cytochrome P450 3A5, and multidrug resistance 1 (MDR1). The patient had wild-type cytochrome P450 3A4 (*1/*1) and variant-type cytochrome P450 3A5 (*3/*3), while MDR1 genes (2677A/G, 3435C/C) were wild-type.

CONCLUSION

Wild-type MDR1 gene product P-glycoprotein expressed in the intestine reduces drug absorption from the gastrointestinal tract and may have contributed to low blood levels of tacrolimus in this patient when tacrolimus was orally administered.

Nationwide observational study of mortality from complicated intra-abdominal infections and the role of bacterial cultures

BACKGROUND

The benefit of taking intra-abdominal cultures during source control procedures in patients with complicated intra-abdominal infection (CIAI) is unknown. The aim of this study was to evaluate whether intra-abdominal cultures reduce the mortality rate of CIAI.

METHODS

The Japanese Diagnosis Procedure Combination database was used to identify adult patients with CIAI who had undergone source control procedures on the first day of admission to hospital between April 2014 and March 2016. In-hospital mortality was compared between patients who did and those who did not have intra-abdominal cultures taken. A generalized linear mixed-effect logistic regression model and a random intercept per hospital were used to adjust for baseline confounders and institutional differences. Subgroup analyses were also performed according to disease cause, site of onset and severity of CIAI.

RESULTS

Intra-abdominal cultures were taken from 16 303 of 41 495 included patients. Multivariable logistic regression analysis showed that patients with intra-abdominal cultures had a significantly lower mortality than those without (odds ratio 0·85, 95 per cent c.i. 0·77 to 0·95). Subgroup analyses revealed statistically significant differences in mortality between patients with and without cultures among those with lower intestinal perforation, biliary tract infection/perforation, healthcare-associated CIAI and high-risk community-acquired CIAI.

CONCLUSIONS

Intra-abdominal cultures obtained during source control procedures may reduce in-hospital mortality, especially in patients with lower intestinal perforation, biliary tract infection/perforation, or healthcare-associated or high-risk community-acquired CIAI.

New precise measurements of muonium hyperfine structure at J-PARC MUSE

High precision measurements of the ground state hyperfine structure (HFS) of muonium is a stringent tool for testing bound-state quantum electrodynamics (QED) theory, determining fundamental constants of the muon magnetic moment and mass, and searches for new physics. Muonium is the most suitable system to test QED because both theoretical and experimental values can be precisely determined. Previous measurements were performed decades ago at LAMPF with uncertainties mostly dominated by statistical errors. At the J-PARC Muon Science Facility (MUSE), the MuSEUM collaboration is planning complementary measurements of muonium HFS both at zero and high magnetic field. The new high-intensity muon beam that will soon be available at H-Line will provide an opportunity to improve the precision of these measurements by one order of magnitude. An overview of the different aspects of these new muonium HFS measurements, the current status of the preparation for high-field measurements, and the latest results at zero field are presented.

Hepatotoxicity, nephrotoxicity, and drug/chemical interaction toxicity of platinum nanoparticles in mice

Nanomaterials are frequently used in microelectronics, cosmetics, and sunscreens. Platinum reagents are commonly used in disease diagnosis, cosmetics, and the food industry. Although research into the development of nanomaterialbased drug delivery systems has yielded promising results, the toxicity of these materials is not fully understood. We investigated the toxicity and drug interactions of 1- and 8-nm diameter platinum nanoparticles (nPt1 and nPt8, respectively) in mice. Acute hepato-renal toxicity of intravenously administered platinum nanoparticles was evaluated biochemically and histologically. Dose-dependent increases in serum markers of hepato-renal function (serum aminotransferases and blood urea nitrogen) were observed following administration of nPt1, whereas nPt8 had no effect, even at 20 mg/kg. Moreover, nPt1 induced interleukin (IL)-6 and IL-1β production 3 and 6 hours after administration. The effect of nPts on drug-induced toxicity was evaluated in mice injected intraperitoneally with carbon tetrachloride or cisplatin, with or without intravenous administration of platinum nanoparticles. All treatments in the absence of nanoparticles were non-lethal and resulted in moderate toxicity. However, exacerbated toxicity was observed in mice injected with carbon tetrachloride or cisplatin together with nPt1, but not in mice co-injected with nPt8. We found that nPt1 cause hepato-renal damage, and the effect is enhanced by chemical inducers of hepatotoxicity and nephrotoxicity. This is the first report demonstrating that nPt1 not only are hepatotoxic and nephrotoxic but also exacerbate drug toxicity. These findings will be useful for future nanotechnology and nanoscience research.

A higher incidence of cleavage failure in oocytes containing smooth endoplasmic reticulum clusters

PURPOSE

In human oocytes, sERCs are one of the dysmorphic phenotypes that have been reported. Significantly reduced pregnancy rates and a comparatively higher number of abnormities in live births appear to be associated with the presence of sERCs in oocytes. However, some reports have shown that healthy babies can be born, without any reduced pregnancy rates, from oocytes observed to contain sERCs. Thus, the clinical and scientific significance of oocytes that harbor sERCs remains controversial.

METHODS

The presence of sERCs was evaluated using a time-lapse system while studying the dynamic changes within oocytes and embryos. Logistic regression analysis was carried out to explore the independent variables for meiotic and mitotic cleavage failure..

RESULTS

The incidence of mitotic cleavage failure and the incidence of meiotic cleavage failure during the second polar body extrusion in oocytes with sERCs were found to be significantly higher than that in oocytes without sERCs. Furthermore, ICSI was found to have a greater frequency of meiotic failure than IVF.

CONCLUSIONS

In cases of cleavage failure, an embryonic cell could become tetraploid and may induce abnormal chromosomal configurations. Some cells exposed to cleavage failure may become trophectoderm cells and form placental abnormalities. Even if they develop into trophectoderm cells, the ICM can be susceptible to further cleavage failure and may in turn cause further aneuploidy. For these reasons, it is important to monitor pregnancies and births derived from oocytes that contained sERCs.

Successful T-cell Replete Hematopoietic Stem Cell Boost Without Conditioning for Late Graft Failure

Late graft failure is a rare but significant complication after allogeneic stem cell transplantation, which is often complicated by severe infections. We report a case of late graft failure, which was successfully treated with a T-cell replete hematopoietic stem cell boost without conditioning that induced rapid engraftment and relieved the patient of infection. Discontinuation of immunosuppressants and nilotinib administration suppressed the host cells. Achieving full donor chimerism allowed us to administer a peripheral blood stem cell boost without conditioning.

Generation of a sensitive TNFR2-specific murine assays system

Tumor necrosis factor (TNF)/TNF receptors (TNFR1/TNFR2) are considered to be potential drug targets to treat refractory diseases, including autoimmune diseases and malignant tumors. However, their specific functions, especially in the case of TNFR2, are poorly understood. In this study, we constructed a mouse TNFR2 (mTNFR2)-mediated biological assay system that shows no effects of mouse TNFR1 (mTNFR1) in order to screen mTNFR2-selective stimulating agents. Mouse TNFR1(-/-)R2(-/-) preadipocytes were transfected with the gene encoding the mTNFR2/mouse Fas (mFas) chimeric receptor in which the extracellular and transmembrane domains of mTNFR2 were fused to the intracellular domain of mFas. Our results demonstrated that this cell line exhibits highly sensitive mTNFR2-mediated cytotoxic effects. We propose that this mTNFR2-mediated biological assay system would be a useful tool to screen for mTNFR2-selective stimulating agents.

Acute type A aortic dissection repair with mild-to-moderate hypothermic circulatory arrest and selective cerebral perfusion

AIM

The purpose of this study was to evaluate surgical results of aortic repair with antegrade selective cerebral perfusion (ASCP) and mild-to-moderate hypothermia (MH) from 28 to 31°C comparing with previous series with hypothermia from 20°C to 27 °C.

METHODS

Between 2000 and 2011, 109 consecutive patients underwent surgical repair for acute type A aortic dissection with circulatory arrest and ASCP and MH in our institution. Mean patient age was 67±11 years old. Total arch replacement was performed in 85 patients (78%). Thirty (27%) patients had shock status preoperatively. The patients were divided into two different subsets, which is group A (circulatory arrest at less than 27.9 °C, N.=70), and group B (at more than 28 °C, N.=39).

RESULTS

The mean extra-corporeal circulation time was 185±47 minutes in group A and 155±38 minutes in group B (P<0.001). The hospital mortality was 11.4% in group A and 10.3% in group B (P>0.05). Permanent neurological deficit occurred in 10 patients (14.3%) in group A, and in 5 (12.8%) in group B (P>0.05). Two (2.8%) paraplegia occurred in group A, and none in group B (P>0.05). The incidence of renal failure requiring hemodialysis was 17.1% in group A and 7.7% in group B, (P>0.05). Respiratory failure after surgery occurred in 27.1% of patients in group A, and 5.1% in group B (P=0.005).

CONCLUSION

Circulatory arrest at more than 28 °C offered sufficient cerebral and distal organ protection for acute type A aortic dissection.