Durvalumab after chemoradiotherapy in non-small cell lung cancer with EGFR mutation: A real-world study (HOT2101)

Durvalumab has been administered to patients with unresectable stage III non-small cell lung cancer (NSCLC). However, it remains unclear whether durvalumab benefits these patients with epidermal growth factor receptor (EGFR) mutation. We conducted a retrospective, multicenter study of patients with EGFR mutation who received chemoradiotherapy (CRT) between June 2018 and March 2021. We assessed patient characteristics, efficacy of durvalumab, and durvalumab safety before and after targeted therapy. We collected data on a total of 673 patients, of whom 401 (59.6%) underwent EGFR mutation testing. Fifty-one patients were EGFR positive and 311 were EGFR negative. In the EGFR-positive group, there were higher proportions of females, never-smokers, and patients with adenocarcinoma histology. Of the 51 patients in the positive group and 311 in the negative group who received CRT, 45 (88.2%) and 247 (79.4%) received durvalumab, with median progression-free survival of 23.0 and 24.2 months in the positive and negative groups, respectively (hazard ratio 1.03; 95% confidence interval: 0.64-1.67). The main adverse event was pneumonitis (positive group: 62.2%; 4.4% grade 3; negative group: 62.3%; 6.9% grade 3). No treatment-related deaths were observed. Of the 45 patients in the positive group who received durvalumab, 14 (31.1%) received targeted therapy after durvalumab at the data cutoff. One patient discontinued targeted therapy after developing pneumonitis. In patients with unresectable stage III NSCLC with EGFR mutation, durvalumab after CRT is potentially safe and effective. This may be a suitable treatment sequence for these patients.

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.

Extended ICI treatment after first-line chemoimmunotherapy could predict the clinical benefit of ramucirumab plus docetaxel in advanced non-small lung cancer: Post hoc analysis from NEJ051 (REACTIVE study)

BACKGROUND

The factors that predict the clinical response to ramucirumab plus docetaxel (RD) after first-line chemoimmunotherapy are unresolved. We explored whether the therapeutic efficacy of prior chemoimmunotherapy could predict the outcome of RD as sequential therapy in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Our study comprised 288 patients with advanced NSCLC who received RD as the second-line treatment after first-line chemoimmunotherapy at 62 Japanese institutions. Chemoimmunotherapy consisted of a platinum-based regimen and immune checkpoint inhibitors (ICIs). The association between several variables and the therapeutic outcome of RD was determined via logistic regression analysis.

RESULTS

Of the 288 patients, 225 (78.1%) received maintenance therapy and 108 (37.5%) received both ICI treatment for >180 days and maintenance therapy. All of 108 patients having ICIs for >180 days received maintenance therapy. Univariate analysis identified performance status, histology (adenocarcinoma), maintenance therapy, and ICI treatment >180 days as significant predictors of better progression-free survival (PFS) and overall survival (OS) after RD administration. Multivariate analysis confirmed that these factors independently predicted favorable PFS and OS. The therapeutic response and PD-L1 expression were not closely associated with outcome after RD treatment. In particular, maintenance therapy >4 cycles was more predictive of the better prognosis for RD treatment.

CONCLUSION

Extended ICI treatment after chemoimmunotherapy and maintenance therapy enhanced the efficacy of second-line RD treatment in patients with advanced NSCLC.

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.

Inhibition of non-homologous end joining mitigates paclitaxel resistance resulting from mitotic slippage in non-small cell lung cancer

Mitotic slippage, which enables cancer cells to bypass cell death by transitioning from mitosis to the G1 phase without undergoing normal cytokinesis, is one likely mechanism of paclitaxel (PTX) resistance. DNA double-strand breaks (DSBs) in the G1 phase are mainly repaired through non-homologous end joining (NHEJ). Therefore, inhibiting NHEJ could augment the PTX-induced cytotoxicity by impeding the repair of PTX-induced DSBs during the G1 phase following mitotic slippage. We aimed to evaluate the effects of NHEJ inhibition on mitotic slippage after PTX treatment in non-small cell lung cancer (NSCLC). H1299, A549, H1975, and H520 NSCLC cell lines were employed. In addition, A-196 and JQ1 were used as NHEJ inhibitors. H1299 cells were PTX-resistant and exhibited an increased frequency of mitotic slippage upon PTX treatment. NHEJ inhibitors significantly augmented the PTX-induced cytotoxicity, DSBs, and apoptosis in H1299 cells. The newly generated PTX-resistant cells were even more prone to mitotic slippage following PTX treatment and susceptible to the combined therapy. Docetaxel further demonstrated synergistic effects with the NHEJ inhibitor in PTX-resistant cells. NHEJ inhibition may overcome intrinsic or acquired PTX resistance resulting from mitotic slippage by synergistically increasing the cytotoxic effects of antimitotic drugs in NSCLC.

A novel eukaryotic RdRP-dependent small RNA pathway represses antiviral immunity by controlling an ERK pathway component in the black-legged tick

Small regulatory RNAs (sRNAs) are involved in antiviral defense and gene regulation. Although roles of RNA-dependent RNA Polymerases (RdRPs) in sRNA biology are extensively studied in nematodes, plants and fungi, understanding of RdRP homologs in other animals is still lacking. Here, we study sRNAs in the ISE6 cell line, which is derived from the black-legged tick, an important vector of human and animal pathogens. We find abundant classes of ~22nt sRNAs that require specific combinations of RdRPs and sRNA effector proteins (Argonautes or AGOs). RdRP1-dependent sRNAs possess 5'-monophosphates and are mainly derived from RNA polymerase III-transcribed genes and repetitive elements. Knockdown of some RdRP homologs misregulates genes including RNAi-related genes and the regulator of immune response Dsor1. Sensor assays demonstrate that Dsor1 is downregulated by RdRP1 through the 3'UTR that contains a target site of RdRP1-dependent repeat-derived sRNAs. Consistent with viral gene repression by the RNAi mechanism using virus-derived small interfering RNAs, viral transcripts are upregulated by AGO knockdown. On the other hand, RdRP1 knockdown unexpectedly results in downregulation of viral transcripts. This effect is dependent on Dsor1, suggesting that antiviral immunity is enhanced by RdRP1 knockdown through Dsor1 upregulation. We propose that tick sRNA pathways control multiple aspects of immune response via RNAi and regulation of signaling pathways.

Notch pathway regulates osimertinib drug‐tolerant persistence in EGFR ‐mutated non‐small cell lung cancer

Osimertinib is a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) that has shown marked antitumor activity in patients with EGFR-mutated non-small-cell lung cancer (NSCLC). However, these effects are transient and most patients develop resistance. Reversible drug-tolerant persister (DTP) cells are defined as a small subpopulation of cells with markedly reduced sensitivity and non-genetic acquired resistance to EGFR-TKIs. Notch is a transmembrane receptor that plays an important role in tumorigenesis. We previously reported that there is significant crosstalk between the Notch and EGFR pathways in NSCLC. Moreover, the Notch pathway is associated with resistance to previous-generation EGFR-TKIs. However, the role of Notch in osimertinib resistance is not fully understood. In this study, we evaluated whether Notch is involved in osimertinib resistance. We show that NOTCH1 and Notch target genes are upregulated in osimertinib DTP cells, and that the addition of a γ-secretase inhibitor (GSI), a Notch inhibitor, impairs drug-tolerant persistence in vitro and in vivo. Compared with osimertinib, combined GSI and osimertinib suppress phospho-ERK partly by enhancing DUSP1 expression. Furthermore, Notch1 and HES1 were upregulated after EGFR-TKI treatment in half of human EGFR-mutated NSCLC tumor tissues. These results suggest that the combination of GSI and osimertinib may be a potential therapy for EGFR-mutated NSCLC.

Atezolizumab plus bevacizumab versus lenvatinib or sorafenib in non-viral unresectable hepatocellular carcinoma: an international propensity score matching analysis

BACKGROUND

A growing body of evidence suggests that non-viral hepatocellular carcinoma (HCC) might benefit less from immunotherapy.

MATERIALS AND METHODS

We carried out a retrospective analysis of prospectively collected data from consecutive patients with non-viral advanced HCC, treated with atezolizumab plus bevacizumab, lenvatinib, or sorafenib, in 36 centers in 4 countries (Italy, Japan, Republic of Korea, and UK). The primary endpoint was overall survival (OS) with atezolizumab plus bevacizumab versus lenvatinib. Secondary endpoints were progression-free survival (PFS) with atezolizumab plus bevacizumab versus lenvatinib, and OS and PFS with atezolizumab plus bevacizumab versus sorafenib. For the primary and secondary endpoints, we carried out the analysis on the whole population first, and then we divided the cohort into two groups: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) population and non-NAFLD/NASH population.

RESULTS

One hundred and ninety patients received atezolizumab plus bevacizumab, 569 patients received lenvatinib, and 210 patients received sorafenib. In the whole population, multivariate analysis showed that treatment with lenvatinib was associated with a longer OS [hazard ratio (HR) 0.65; 95% confidence interval (CI) 0.44-0.95; P = 0.0268] and PFS (HR 0.67; 95% CI 0.51-0.86; P = 0.002) compared to atezolizumab plus bevacizumab. In the NAFLD/NASH population, multivariate analysis confirmed that lenvatinib treatment was associated with a longer OS (HR 0.46; 95% CI 0.26-0.84; P = 0.0110) and PFS (HR 0.55; 95% CI 0.38-0.82; P = 0.031) compared to atezolizumab plus bevacizumab. In the subgroup of non-NAFLD/NASH patients, no difference in OS or PFS was observed between patients treated with lenvatinib and those treated with atezolizumab plus bevacizumab. All these results were confirmed following propensity score matching analysis. By comparing patients receiving atezolizumab plus bevacizumab versus sorafenib, no statistically significant difference in survival was observed.

CONCLUSIONS

The present analysis conducted on a large number of advanced non-viral HCC patients showed for the first time that treatment with lenvatinib is associated with a significant survival benefit compared to atezolizumab plus bevacizumab, in particular in patients with NAFLD/NASH-related HCC.

Nonalcoholic steatohepatitis in hepatocarcinoma: new insights about its prognostic role in patients treated with lenvatinib

BACKGROUND

Hepatocellular carcinoma (HCC) treatment remains a big challenge in the field of oncology. The liver disease (viral or not viral) underlying HCC turned out to be crucial in determining the biologic behavior of the tumor, including its response to treatment. The aim of this analysis was to investigate the role of the etiology of the underlying liver disease in survival outcomes.

PATIENTS AND METHODS

We conducted a multicenter retrospective study on a large cohort of patients treated with lenvatinib as first-line therapy for advanced HCC from both Eastern and Western institutions. Univariate and multivariate analyses were performed.

RESULTS

Among the 1232 lenvatinib-treated HCC patients, 453 (36.8%) were hepatitis C virus positive, 268 hepatitis B virus positive (21.8%), 236 nonalcoholic steatohepatitis (NASH) correlate (19.2%) and 275 had other etiologies (22.3%). The median progression-free survival (mPFS) was 6.2 months [95% confidence interval (CI) 5.9-6.7 months] and the median overall survival (mOS) was 15.8 months (95% CI 14.9-17.2 months). In the univariate analysis for OS NASH-HCC was associated with longer mOS [22.2 versus 15.1 months; hazard ratio (HR) 0.69; 95% CI 0.56-0.85; P = 0.0006]. In the univariate analysis for PFS NASH-HCC was associated with longer mPFS (7.5 versus 6.5 months; HR 0.84; 95% CI 0.71-0.99; P = 0.0436). The multivariate analysis confirmed NASH-HCC (HR 0.64; 95% CI 0.48-0.86; P = 0.0028) as an independent prognostic factor for OS, along with albumin-bilirubin (ALBI) grade, extrahepatic spread, neutrophil-to-lymphocyte ratio, portal vein thrombosis, Eastern Cooperative Oncology Group (ECOG) performance status and alpha-fetoprotein. An interaction test was performed between sorafenib and lenvatinib cohorts and the results highlighted the positive predictive role of NASH in favor of the lenvatinib arm (P = 0.0047).

CONCLUSION

NASH has been identified as an independent prognostic factor in a large cohort of patients with advanced HCC treated with lenvatinib, thereby suggesting the role of the etiology in the selection of patients for tyrosine kinase treatment. If validated, this result could provide new insights useful to improve the management of these patients.

Massive Hemorrhage Due to Cervical Endometriotic Cyst Rupture: Two Case Reports and a Literature Review

BACKGROUND Endometriosis is defined as the growth of ectopic endometrial tissue beyond the uterine cavity, and endometriosis on the uterine cervix is a rare variant. Although asymptomatic patients with cervical endometriosis or those with minor symptoms are treated conservatively, there are reports of life-threatening hemorrhage due to cervical endometriosis. Here, we report 2 cases of massive genital bleeding caused by cervical endometriotic cysts and we performed a literature review. CASE REPORT Case 1: A 32-year-old woman presented to our hospital due to massive genital bleeding on her 11th day of menstruation. An arterial hemorrhage in a cervical endometriotic cyst was suspected. As pressure hemostasis proved difficult, urgent uterine artery embolization (UAE) by interventional radiology was performed. Angiography during the UAE showed extravascular leakage from the branch of the left uterine artery. After embolization, hemostasis was achieved. No further genital bleeding was observed, and transvaginal ultrasound showed the cyst has continued to shrink for 9 months after the UAE with sequential dienogest, a progesterone receptor agonist, treatment. Case 2: A 43-year-old woman presented to our hospital with increasing massive genital bleeding after completing a 12-day course of 0.5 mg of norgestrel and 0.05 mg of ethinyl estradiol as a treatment for irregular intermenstrual bleeding. We suspected cervical endometriotic cyst rupture on imaging and performed an urgent laparoscopic total hysterectomy. In the excised uterine specimen, a cystic lesion that contained old, blood-like fluid was macroscopically observed in the cervix and was diagnosed pathologically as endometriosis. CONCLUSIONS Cervical endometriotic cyst rupture is rare; however, it should be kept in mind as a differential diagnosis when treating massive genital bleeding because urgent intervention is sometimes required to control the bleeding.

Clinical and pathological analysis of companion diagnostic testing of microsatellite instability-high for pembrolizumab in gynaecologic malignancy

BACKGROUND

Microsatellite instability-high is a known biomarker for anti-PD-1/PD-L1 immune checkpoint therapy. It is also a known tumour feature of Lynch syndrome, detected most frequently in endometrial cancer. However, it remains unclear how microsatellite instability testing is carried out in the clinical field.

METHODS

Ninety-nine patients with gynaecological malignant tumours who underwent microsatellite instability testing as a companion diagnosis for pembrolizumab and 16 patients who previously underwent microsatellite instability testing as a screening for Lynch syndrome were recruited. Clinical information, microsatellite instability status, outcomes, genetic assessments and information about cancer tissue were retrospectively analysed.

RESULTS

Ninety-nine patients had 101 gynaecologic malignant tumours including 26 endometrial, 38 ovarian and 28 cervical cancers, 9 with other tumours including 2 synchronous endometrial and ovarian cancers. All tissue samples were successfully tested, even though some were ≥10-year-old samples. Three cases (3.0%, 3/99) showed microsatellite instability-high; all cases were endometrial cancers with one case of synchronous endometrial and ovarian cancer [11.5% (3/26) in endometrial cancer, 2.6% (1/38) in ovarian cancer], and there was no microsatellite instability-high in cervical and other cancers. One of the endometrial cancer patients received pembrolizumab treatment, but finally died of cancer. Two other cases underwent genetic testing; both were diagnosed as Lynch syndrome. Six cases (37.5%) showed microsatellite instability-high in screening for Lynch syndrome.

CONCLUSIONS

Microsatellite instability-high was less commonly detected as a companion diagnosis for pembrolizumab in unselected gynaecologic patients. Genetic counselling should be always provided along with treatment selection.

Caste development and sex ratio of the Ryukyu drywood termite Neotermes sugioi and its potential mechanisms

Sex allocation is one of the most studied traits in evolutionary biology because its theoretical predictions match the empirical data. Here, using the Ryukyu dry-wood termite Neotermes sugioi, we investigated several factors that could bias the sex allocation in three populations (Okinawa, Ishigaki/Iriomote, and Yonaguni). Our survey showed that there were more queen-only colonies than king-only colonies in these populations, suggesting a longer lifespan of the queens than that of the kings. In this condition, sex-asymmetric reproductive value (SRV) theory predicts female bias, because even after the short-lived kings die, the long-lived queens can continue reproduction with their sons. However, sex allocation in this species seemed to be biased toward males. Furthermore, we examined the possibility of intrasexual competition among siblings (ICS). If ICS is the cause of the bias, the allocation is expected to change depending on the total investment in sexual offspring. However, the biomass of both male and female alates increased linearly with the increase in the total biomass of the alates in these populations. Thus, neither the SRV nor the ICS theory could explain the male-biased sex ratio of N. sugioi. On the basis of these results, we discuss the remaining possibilities in this species.

Abstract 1991: Notch pathway regulates proliferation of osimertinib drug-tolerant cells in epidermal growth factor receptor mutated non-small cell lung cancer

Background: Osimertinib is a third generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), which has shown remarkable antitumor activity in EGFR mutated patients with or without T790M mutation associated with previous-generation EGFR TKIs. But these effects are transient and the majority of patients develop resistance. A recently identified reversibly drug tolerant (DT) cells are defined as a small subpopulation of cells with remarkably reduced sensitivity to targeted drugs and noticed as non-genetic acquired resistance to EGFR-TKI. Notch is a transmembrane receptor that plays an important role in tumorigenesis. Notch pathway is associated with the resistance to previous-generation EGFR TKIs, however, the role of Notch is not fully understood in osimertinib treatment. In this study, we evaluated whether Notch was involved in resistance mechanism to osimertinib, using osimertinib DT cells and osimertinib resistant cells.

Methods: We isolated osimertinib resistant cells by stepwise exposure of human non-small cell lung cancer (NSCLC) cells with EGFR mutations (PC-9 cells and H1975 cells) to osimertinib (0.5-5 μmol/L). The osimertinib resistant cells were examined for EGFR mutations by direct sequencing, each time the concentration of osimertinib was increased. In resistant cells, original EGFR mutations were continuously observed without other new EGFR mutations. We isolated DT cells by exposure of human NSCLC cells with EGFR mutations (PC-9 cells and H1975 cells) to osimertinib (3 μmol/L) or combination of osimertinib and γ-secretase inhibitor (GSI) (1 μmol/L) for 9 days. The proteins of EGFR, ERK1/2, AKT, Notch1, HES1 and HEY were examined using western blot. The cytotoxic effect of osimertinib and GSI was evaluated using MTT assay and clonogenic assay in vitro.

Results: The phosphorylation of EGFR was decreased and Notch1 expression was increased in resistant cells compared to the parental cells. Combination of osimertinib and GSI inhibited the proliferation of parental cells compared to osimertinib or GSI single treatment, but did not reduce the viability of resistant cells. DT cells were highly insensitive to osimertinib compared with their parental cells. Continuous administration of osimertinib and GSI delayed the proliferation and colony formation of DT cells compared to osimertinib alone. The phosphorylation of EGFR, ERK1/2, and AKT was decreased and Notch1 expression was increased in DT cells compared to the parental cells. Although up-regulated Notch1 in DT cells was inhibited when GSI was administered together with osimertinib, phosphorylation of EGFR, ERK1/2 and AKT was unchanged, suggesting that other bypass pathways might be suppressed by GSI.

Conclusions: Combination of osimertinib and GSI delays proliferation of DT cells in EGFR mutated NSCLC by modulating Notch pathway.

Citation Format: Hirofumi Takahashi, Jun Sakakibara-Konishi, Shotaro Ito, Kosuke Tsuji, Eiki Kikuchi, Junko Kikuchi, Naofumi Shinagawa, Satoshi Konno. Notch pathway regulates proliferation of osimertinib drug-tolerant cells in epidermal growth factor receptor mutated non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1991.

Dynamics of the Chemically Driven Densification of Barium Titanate Using Molten Hydroxides

Molten hydroxides, often used for crystal growth and nanoparticle synthesis, have recently been applied for the single step densification of several inorganic materials under moderate uniaxial pressures and 1000 °C below their usual sintering temperatures. The latter approach, termed cold sintering process (CSP), is a mechanochemically driven process that enables the densification of inorganic materials through a dissolution-precipitation creep mechanism. In this study, we report the main densification mechanisms of BaTiO₃ in a NaOH-KOH eutectic mixture. A chemical insight at the atomistic level, investigated by ReaxFF molecular dynamics simulations, offers plausible ionic complex formation scenarios and reactions at the BaTiO₃/molten hydroxide interface, enabling the dissolution-precipitation reactions and the subsequent cold sintering of BaTiO₃.

Inhibition of fibrotic changes in infrapatellar fat pad alleviates persistent pain and articular cartilage degeneration in monoiodoacetic acid-induced rat arthritis model

OBJECTIVE

We have reported that fibrotic changes in infrapatellar fat pad (IFP) after acute joint inflammation are closely associated with persistent pain in rats. In this study, to examine the effects of anti-fibrotic treatment on persistent pain, we used C-type natriuretic peptides (CNP) at the recovery phase after acute joint inflammation.

DESIGN

Thirty-two male Wistar rats were used in this study. Monoiodoacetic acid (MIA) was injected intra-articularly to induce IFP fibrosis and persistent pain. CNP was injected after acute inflammatory phase in the same knee joint. Time-course pain-avoidance behavior tests and histological analyses were performed to examine the effects of CNP.

RESULTS

Histological evaluations indicated that intra-articular injection of CNP inhibited fibrotic changes in IFP after acute inflammation. Incapacitance tests indicated that MIA injection into rat knee joint quickly decreased the percent weight on ipsilateral limb. In the vehicle group, the decrease was maintained up to day 28, suggesting that pain persistence occurred after acute inflammation (Day 0/Day 28, Est Dif -8.15, CI -10.78∼-5.53, Linear mixed-effect model). In contrast, the pain was alleviated in the CNP group after day 14 (Day0/Day 14, -0.51, -2.62-1.59). In addition, we observed significant improvement in the degree of articular cartilage degeneration at day 14 in the CNP group (OARSI score: vehicle 16.14 ± 4.37 vs CNP 6.87 ± 3.44, P < 0.01; Wilcoxon rank sum test).

CONCLUSION

Fibrotic changes in IFP may play important roles in both persistent pain and articular cartilage degeneration.

Evaluation of preoperative prediction of intestinal invasion in patients with ovarian cancer

Objective

To optimize prediction for intestinal invasion of epithelial ovarian cancer. It is important to achieve debulking surgery to improve prognosis in ovarian cancer; intestinal resection is adopted if the cancer is invaded and resectable, but the preoperative evaluation method of intestinal invasion is still controversial.

Methods

Patients (n = 174) who underwent primary debulking surgery for epithelial ovarian cancer were recruited for retrospective study; 28 and 146 patients were classified into the invasion and non‐invasion groups, whether they needed intestinal resection or not. We collected clinical data including evaluation of computed tomography (CT), magnetic resonance imaging (MRI), and barium contrast radiography, and analyzed their accuracy.

Results

The sensitivity and specificity for intestinal invasion were 33.3% and 98.6%, 42.9% and 98.6%, and 66.7% and 93.9% in CT, MRI, and barium contrast radiography, respectively. CT and MRI combined showed a sensitivity of 58.3% and specificity of 96.9%; all three methods combined was the most sensitive combination, showing a sensitivity of 79.2% and specificity of 90.8%.

Conclusion

Combination of CT, MRI, and barium contrast radiography predicts intestinal invasion with the highest sensitivity. These three modalities, however, could not predict all intestinal invasion. Patients should be informed of the possibility of unexpected extensive resection.

Combination of CT, MRI, and barium contrast radiography give the best prediction of intestinal invasion in ovarian cancer.

Proposal of COVID-19 Clinical Risk Score for the management of suspected COVID-19 cases: a case control study

BACKGROUND

No clinical scoring system has yet been established to estimate the likelihood of coronavirus disease (COVID-19) and determine the suitability of diagnostic testing in suspected COVID-19 patients.

METHODS

This was a single-center, retrospective, observational study of patients with suspected COVID-19 and confirmed COVID-19. Patient background, clinical course, laboratory and computed tomography (CT) findings, and the presence of alternative diagnoses were evaluated. Clinical risk scores were developed based on clinical differences between patients with and without COVID-19.

RESULTS

Among 110 patients suspected of having COVID-19, 60.9% underwent polymerase chain reaction (PCR) testing based on the judgment of physicians. Two patients were found to have COVID-19. The clinical characteristics of 108 non-COVID-19 patients were compared with those of 23 confirmed COVID-19 patients. Patients with COVID-19 were more likely to have a history of high-risk exposures and an abnormal sense of taste and smell. The COVID-19 group had significantly higher rates of subnormal white blood cell counts, lower eosinophil counts, and lower procalcitonin levels than the non-COVID-19 group. When blood test results, CT findings, and the presence of alternative diagnoses were scored on an 11-point scale (i.e., "COVID-19 Clinical Risk Score"), the COVID-19 group scored significantly higher than the non-COVID-19 group, more than four points in the COVID-19 group. All non-COVID patients who did not undergo PCR had a score of 4 or less.

CONCLUSIONS

The COVID-19 Clinical Risk Score may enable the risk classification of patients suspected of having COVID-19 and can help in decision-making in clinical practice, including appropriateness of diagnostic testing. Further studies and prospective validation with an increased sample size are required.

Evaluation of safety and diagnostic performance for flexible hysteroscopy in 1591 outpatient cases

BACKGROUND

To date, only few large studies are available concerning the safety and diagnostic concordance rates of outpatient flexible hysteroscopy. In our institution, outpatient hysteroscopy has been routinely and educationally applied Kosuke Tsuji to intrauterine lesions; thus, we retrospectively investigated the institution's outpatient flexible hysteroscopy cases.

METHODS

A total of 1591 cases of outpatient flexible hysteroscopy conducted at our institution in 2012-2016 were retrospectively analyzed in terms of their clinical background, complications and diagnostic concordance rates.

RESULTS

A total of 1591 cases included 546 cases of benign tumors (317 endometrial polyps, 168 myomas and 61 endometrial hyperplasia), 361 cases of atypical endometrial hyperplasia, 571 cases of endometrial cancers and 113 cases of other diagnoses. No major complications, including uterine perforation, occurred. However, one patient (0.06%) was diagnosed with septic shock caused by intrauterine infection that required prolonged immunosuppressive drug administration. Meanwhile, 335 patients diagnosed with benign tumors through outpatient flexible hysteroscopy underwent operation, and the diagnostic concordance rate was 74.6% (250 cases). However, this rate included 14 cases (4.2%) diagnosed with malignant tumors postoperatively. In preoperative endometrial cancer cases, the sensitivity and specificity for cervical invasion diagnosis were 39.4 and 90.8%, respectively. In addition, only one patient manifested positive ascites cytology intraoperatively, possibly caused by outpatient hysteroscopy.

CONCLUSIONS

Outpatient flexible hysteroscopy is highly safe, with a slight negligible effect on ascites cytology. However, the diagnosis should be determined by multidisciplinary approaches, as hysteroscopy alone can miss malignancy.

Impact of the COVID-19 epidemic at a high-volume facility in gynecological oncology in Tokyo, Japan: a single-center experience

BACKGROUND

The number of cases of novel coronavirus disease 2019 (COVID-19) in Japan have risen since the first case was reported on January 24, 2020, and 6225 infections have been reported as of June 30, 2020. On April 8, 2020, our hospital began screening patients via pre-admission reverse transcriptase-polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and chest computed tomography (CT). Although no patients exhibited apparent pneumonia, treatment delay or changes in treatment plans were required for a few patients based on the results of screening tests. During an emerging infectious disease pandemic, the likelihood of being infected, as well as the disease itself, affects clinical decision making in several ways. We summarized and presented our experience.

CASE PRESENTATION

After the introduction of pre-admission screening, RT-PCR and CT were performed in 200 and 76 patients, respectively, as of June 30, 2020. The treatment of five patients, including two patients with cervical cancer, two patients with ovarian tumors, and one patient with ovarian cancer, was affected by the results. Two asymptomatic RT-PCR-positive patients did not develop COVID-19, but their treatment was delayed until the confirmation of negative results. The other three patients were RT-PCR-negative, but abnormal CT findings suggested the possibility of COVID-19, which delayed treatment. The patients receiving first-line preoperative chemotherapy for ovarian cancer had clinically evident exacerbations because of the treatment delay.

CONCLUSION

During the epidemic phase of an emerging infectious disease, we found that COVID-19 has several other effects besides its incidence. The postponing treatment was the most common, therefore, treatment of ovarian tumors and ovarian cancer was considered to be the most likely to be affected among gynecological diseases. Protocols that allow for easy over-diagnosis can be disadvantageous, mainly because of treatment delays, and therefore, the protocols must be developed in light of the local infection situation.

Hysteroscopic Photodynamic Diagnosis Using 5-Aminolevulinic Acid: A High-Sensitivity Diagnostic Method for Uterine Endometrial Malignant Diseases

STUDY OBJECTIVE

To examine the diagnostic accuracy of hysteroscopic photodynamic diagnosis (PDD) using 5-aminolevulinic acid (5ALA) in patients with endometrial cancer and premalignant atypical endometrial hyperplasia.

DESIGN

A single-center, open-label, exploratory intervention study.

SETTING

University Hospital in Japan.

PATIENTS

Thirty-four patients who underwent hysteroscopic resection in the Department of Obstetrics and Gynecology at Keio University Hospital.

INTERVENTIONS

Patients were given 5ALA orally approximately 3 hours before surgery and underwent observation of the uterine cavity and endometrial biopsy using 5ALA-PDD during hysteroscopic resection. Specimens were diagnosed histopathologically and the diagnostic sensitivity and specificity of hysteroscopic 5ALA-PDD for malignancy in the uterine cavity was determined. Red (R), blue (B), and green (G) intensity values were determined from PDD images, and the relationships of histopathological diagnosis with these values were used to develop a model for objective diagnosis of uterine malignancy.

MEASUREMENTS AND MAIN RESULTS

Three patients were excluded from the study because of failure of the endoscope system. A total of 113 specimens were collected endoscopically. The sensitivity and specificity of 5ALA-PDD for diagnosis of malignancy in the uterine cavity were 93.8% and 51.9%, respectively. The R/B ratio in imaging analysis was highest in malignant lesions, followed by benign lesions and normal uterine tissue, with significant differences among these groups (p <.05). The R/B and G/B ratios were used in a formula for prediction of malignancy based on logistic regression and the area under the receiver operating characteristic curve for this formula was 0.838. At a formula cutoff value of 0.220, the sensitivity and specificity for diagnosis of malignant disease were 90.6% and 65.4%, respectively.

CONCLUSION

To our knowledge, this is the first study of the diagnostic accuracy of 5ALA-PDD for malignancies in the uterine cavity. Hysteroscopic 5ALA-PDD had higher sensitivity and identifiability of lesions. These findings suggest that hysteroscopic 5ALA-PDD may be useful for diagnosis of minute lesions.

Lung metastasis from gastric cancer presenting as diffuse ground-glass opacities

Most metastatic lung tumors display well-defined, round, multiple nodular shadows, whereas the presence of diffuse ground-glass opacities on chest computed tomography generally suggests non-malignant conditions. Here, we report an unusual case of pulmonary metastasis from gastric cancer in which diffuse ground-glass opacities were observed in all lung segments. A 59-year-old man with a 3-month history of worsening chest pain and shortness of breath was referred to the pulmonary clinic. Chest computed tomography revealed low attenuation areas, suggesting emphysema, along with diffuse ground-glass opacities and interlobular septal thickening in both lungs. A transbronchial lung biopsy specimen revealed signet-ring cell carcinoma infiltrating the alveolar septa. Immunohistochemical staining of the cancer cells was positive for CDX-2, cytokeratin 7, and cytokeratin 20, and negative for surfactant apoprotein-A, TTF-1, and Napsin A. Gastrointestinal endoscopy revealed an ulcerative tumor in the stomach, and a biopsy from the tumor demonstrated malignant cells with similar morphology and immunophenotypes as those in the lungs. The final diagnosis was diffuse lung metastasis from gastric cancer. Our case shows that although multiple, well-defined nodules are typically considered to be the classic presentation of pulmonary metastasis, clinicians should also be aware of the possibility of pulmonary metastasis presenting as diffuse ground-glass opacities.

Upregulation of IGF2R evades lysosomal dysfunction-induced apoptosis of cervical cancer cells via transport of cathepsins

Cervical cancer is the most common gynecological malignancy in the world; however, the survival rates of advanced-stage and recurrent cervical cancer patients remain poor. The multifaced protein insulin-like growth factor 2 receptor (IGF2R) has various ligands, represented as IGF-2 and mannose-6-phosphate (M6P)-tagged proteins. Regarding its antagonistic activity as an IGF1R signal, IGF2R is currently considered a tumor suppressor gene, whereas its significance as an M6P receptor is still unclear. Here, on the basis of transcriptome analysis of TCGA and GEO open datasets, we show that IGF2R is upregulated and correlated with poor prognosis in cervical cancer. Several experiments using cervical cancer cell lines revealed that IGF2R depletion induced apoptosis, decreased cell viability, and increased vulnerability to certain anticancer drug cisplatin. In contrast to its negligible impact in IGF1R signaling, loss of IGF2R disrupted the Golgi-to-lysosome transport of M6P-tagged cathepsins, resulting in decreased lysosomal activity, with their abnormal accumulation and dysfunction of both autophagy and mitophagy, which cause the accumulation of misfolded proteins and production of reactive oxygen species. Taken together, IGF2R has an oncogenic role through transportation of M6P-tagged cargo in cervical cancer and can be used as a predictive biomarker for prognostic classification.

Determination of Total Dietary Fiber in Selected Foods Containing Resistant Maltodextrin by Enzymatic-Gravimetric Method and Liquid Chromatography: Collaborative Study

A method was developed for determination of total dietary fiber (TDF) in foods containing resistant maltodextrin (RMD) which includes nondigestible carbohydrates that are not fully recovered as dietary fiber by conventional TDF methods such as AOAC 985.29 or 991.43. Because the average molecular weight (MW) of RMD is 2000 daltons, lower MW soluble dietary fiber components do not precipitate in 78% ethanol; therefore, RMD is not completely quantitated as dietary fiber by current AOAC methods. The accuracy and precision of the method was evaluated through an AOAC collaborative study. Ten laboratories participated and assayed 12 test portions (6 blind duplicates) containing RMD. The 6 test pairs ranged from 1.5 to 100% RMD. The method consisted of the following steps: (1) The insoluble dietary fiber (IDF) and high MW soluble dietary fiber (HMWSDF) were determined by AOAC 985.29. (2) Ion exchange resins were used to remove salts and proteins contained in the AOAC 985.29 filtrates (including ethanol and acetone). (3) The amount of low MWRMD (LMWRMD) in the filtrates were determined by liquid chromatography. (4) The TDF was calculated by summation of the IDF, HMWSDF, and LMWRMD fractions having nondigestible carbohydrates with a degree of polymerization of 3 and higher. Repeatability standard deviations (RSDr) were 1.33–7.46%, calculated by including outliers, and 1.33–6.10%, calculated by not including outliers. Reproducibility standard deviations (RSDR) were 2.48–9.39%, calculated by including outliers, and 1.79–9.39%, calculated by not including outliers. This method is recommended for adoption as Official First Action.

Primary malignant melanoma of the uterine cervix or vagina which were successfully treated with nivolumab

Primary malignant melanomas (MM) originating from the gynecological tract are rare. They respond poorly to immunotherapy when compared with cutaneous MM. This study reports two cases. The first is of a 54-year-old woman with a cervical amelanotic polypoid mass who was diagnosed as having stage IB1 cervical melanoma according to the International Federation of Gynecology and Obstetrics system. At 17 months post-surgery, a computed tomography examination revealed recurrence of a 68 mm pelvic tumor. The second case is of a 37-year-old woman with a 7 cm hemorrhagic mass on the vaginal wall. The patient was diagnosed as having stage IV vaginal melanoma according to the American Joint Committee on Cancer definition. Both patients received nivolumab therapy, programmed cell death receptor 1 monoclonal antibodies, and the tumors almost disappeared. These cases may add the possibility of using colposcopy with narrow-band imaging and positron-emission tomography to diagnose and evaluate primary MM.

Reproductive interference in live-bearing fish: the male guppy is a potential biological agent for eradicating invasive mosquitofish

The eradication of invasive exotic species is desirable but often infeasible. Here, we show that male guppies are a potential biological agent for eradicating invasive mosquitofish through the mechanism of reproductive interference, which is defined as any sexual behavior erratically directed at a different species that damages female and/or male fitness. Together with decades of data on species distribution, our field surveys suggest that mosquitofish initially became established on Okinawa Island before being replaced by the more recently introduced guppies. More importantly, our laboratory experiments suggest that reproductive interference was one of the mechanisms underlying this species exclusion, and that in this case, the negative effects were asymmetric, i.e., they only impacted mosquitofish. Reproductive interference may offer a safer and more convenient method of biological control than the traditional sterile male release method because radiation is not necessary.

Atypical endometrial hyperplasia diagnosed by hysteroscopic photodynamic diagnosis using 5-aminolevulinic acid

Endometrial cancer is diagnosed by endometrial biopsy, imaging and hysteroscopy, but it is sometimes difficult to find small lesions. 5-aminolevulinic acid (5ALA) forms protoporphyrin IX, which accumulates in tumors and fluoresces upon light irradiation. 5ALA is used for photodynamic diagnosis (PDD) for detecting malignant diseases. A 60-year-old female was suspected to have endometrial cancer by magnetic resonance imaging. Endometrial biopsy was performed repeatedly, but no malignant lesion was detected. We performed hysteroscopic 5ALA-PDD and could detect a small lesion. The lesion was excised and diagnosed as atypical endometrial hyperplasia histopathologically. This is the first report that showed hysteroscopic 5ALA-PDD can contribute to diagnosis of early-stage neoplastic lesion in the uterine cavity.

Warburg effect in Gynecologic cancers

Mammalian cells produce energy by oxidative phosphorylation under aerobic conditions. However, in the 1920s, Otto Warburg reported the so-called "Warburg effect" in which cancer cells produce ATP that is biased toward glycolysis rather than mitochondrial oxidative phosphorylation not only in anaerobic environment but also in aerobic environment. Glucose is converted into lactate without going into mitochondria after being metabolized in glycolysis. Compared with oxidative phosphorylation, the glycolysis has a faster ATP production rate but it is very inefficient, resulting in cancer cells consuming a large amount of glucose. Increased glucose metabolism has become a biomarker for cancer cells and has led to the development of positron emission tomography with fluorodeoxyglucose. Till date, the Warburg effect has been an inefficient system for cancer cells with regard to efficient energy production, but since the consumption of oxygen can be suppressed as the tumor grows in mass, it is thought that the Warburg effect is advantageous in this situation wherein the tumor can increase despite the lack of vessels. In addition, an increased lactate by the glycolysis causes acidosis in the microenvironment of tissues, which is thought to damage the surrounding normal tissues and favor the invasion and metastasis of cancer. Thus, Warburg effect is one of the key mechanisms for cancer development and will be the next promising target. In this review, we introduce key players that can be targeted in the Warburg effect and outline the prospects of treatment, targeting the Warburg effect in gynecological cancer.

Transcriptome characterization of male accessory glands in ants to identify molecules involved in their reproductive success

In insects, seminal fluid proteins that are produced by male accessory glands and transferred to females during mating have key functions in sperm competition and sperm physiology that lead to male reproductive success. In ants, male reproductive success also depends on the longevity of sperm stored in the queen's spermatheca because their sexual offspring are usually produced only after a prolonged storage period. We identified genes that were up-regulated in the male accessory glands relative to the bodies of Crematogaster osakensis to characterize the reproductive molecules associated with male reproductive success in ants. We found novel genes that had no hits in a homology search and that were predominantly expressed in the accessory glands. These reproductive proteins may have evolved under rapid positive selection for reproductive success in the species. Furthermore, we discovered that three spermatheca-specific genes of C. osakensis queens were also enriched in the accessory glands relative to the bodies of males. These genes may be important for maintaining the sperm quality continuously from ejaculation by males to prolonged storage by queens. This research provides crucial information about the molecular mechanisms of sperm maintenance and sexual selection in ants, and also insight into the evolution of reproductive strategies in insects.

Screening for Lynch syndrome using risk assessment criteria in patients with ovarian cancer

Objective

Lynch syndrome is a cancer predisposition syndrome caused by germline mutation of DNA mismatch repair (MMR) genes. Lynch syndrome only causes about 0.4% of cases of ovarian cancer, which suggests that universal screening may not be cost-efficient. However, the frequency of Lynch syndrome in ovarian cancer is unclear in the Asian population. The goal of the study was to investigate a screening strategy using family history.

Methods

The subjects were 129 patients with ovarian cancer. Clinical and family history were collected using a self-administered questionnaire, and Society of Gynecologic Oncology (SGO) criteria 2007 and PREMM₅ were used for risk assessment. Microsatellite instability, immunohistochemistry, and methylation of MMR genes were analyzed.

Results

Of the 129 cases, 25 (19.4%) met the SGO criteria, and 4 of these 25 had MSI-high and MMR deficiency. Two cases had loss of MSH2 and MSH6, indicating MSH2 mutation, and the other two had loss of MLH1 and PMS2, including one without MLH1 methylation indicating MLH1 mutation. These results show that screening using family history can detect Lynch syndrome in 12.0% (3/25) of ovarian cancer cases. The 3 cases were positive for PREMM₅, but negative for Amsterdam II criteria and revised Bethesda guidelines. Genetic testing in one case with MSH2 and MSH6 deficiency confirmed the diagnosis of Lynch syndrome with MSH2 mutation.

Conclusion

This is the first study of screening for Lynch syndrome in ovarian cancer using clinical and family history in an Asian population. This approach may be effective for diagnosis in these patients.

In Vitro and in Vivo Grafting of Xeno Pig Fetal Liver Fragments Using Ultrafiltration Membrane

Transplantation of xeno fetal liver fragments (FLF) could be an alternative or supplementary therapy for acute and chronic liver failure not resolved by routine medical therapies. However, the xenografts themselves are rejected by the host immune system. To overcome these problems, immunoisolate capsules with various cutoff points, from 50,000 (YM30) to 500,000 (ZM500) were tested for their protective effects on FLF graft survival. In an in vitro study, the capsule with the smallest cutoff size (YM30) had an excellent protective effect on the grafts it contained, and showed the lowest GOT values in the culture supernatant and the normal histological structure. In an in vivo study using rats, the same capsule enabled a FLF graft to survive as long as 21 days, even with severe IgG deposition on and within the graft. In another in vivo study, which used beagle dog, however, it did not improve the natural course of survival of the graft, which had totally degenerated by day 7. In conclusion, 1) Immunocapsules, especially those with the smallest cutoff values, impeded the infiltration of the (xeno) humoral attacking factor, but the blocking effect was not complete, as shown by the immunoglobulin (IgG) deposit on the grafts they contained. 2) The FLFs with capsules survived longer than those without capsules—only in rats, not in beagles. This difference may be attributable to the difference of the extent of humoral or nutritional response to the xenografts.

Dielectric relaxation and localized electron hopping in colossal dielectric (Nb,In)-doped TiO2 rutile nanoceramics

The large dielectric relaxation and the frequency-dependent a.c. conductance were successfully explained by a modified electron hopping model.

Monoiodoacetic acid induces arthritis and synovitis in rats in a dose- and time-dependent manner: proposed model-specific scoring systems

OBJECTIVE

In a rat monoiodoacetic acid (MIA)-induced arthritis model, the amount of MIA commonly used was too high, resulting in rapid bone destruction. We examined the effect of MIA concentrations on articular cartilage and infrapatellar fat pad (IFP). We also established an original system for "macroscopic cartilage and bone score" and "IFP inflammation score" specific to the rat MIA-induced arthritis model.

DESIGN

Male Wistar rats received a single intra-articular injection of MIA in the knee. The amount of MIA was 0.1, 0.2, 0.5, and 1 mg respectively. Articular cartilage was evaluated at 2-12 weeks. IFP was also observed at 3-14 days.

RESULTS

Macroscopically, low MIA doses induced punctate depressions on the cartilage surface, and cartilage erosion proceeded slowly over 12 weeks, while higher MIA doses already induced cartilage erosion at 2 weeks, followed by bone destruction. MIA macroscopic cartilage and bone score, OARSI histological score, and Mankin score increased in a dose- and time-dependent manner. The IFP inflammation score peaked at 5 days in low dose groups, then decreased, while in high dose groups, the IFP score continued to increase over 14 days due to IFP fibrosis.

CONCLUSIONS

Punctate depressions, cartilage erosion, and bone destruction were observed in the MIA-induced arthritis model. The macroscopic cartilage and bone scoring enabled the quantification of cartilage degeneration and demonstrated that MIA-induced arthritis progressed in a dose- and time-dependent manner. IFP inflammation scores revealed that 0.2 mg MIA induced reversible synovitis, while 1 mg MIA induced fibrosis of the IFP body.

Not single but periodic injections of synovial mesenchymal stem cells maintain viable cells in knees and inhibit osteoarthritis progression in rats

OBJECTIVE

We investigated the effects of single or repetitive intra-articular injections of synovial mesenchymal stem cells (MSCs) on a rat osteoarthritis (OA) model, and elucidated the behaviors and underlying mechanisms of the stem cells after the injection.

DESIGN

One week after the transection of the anterior cruciate ligament (ACL) of wild type Lewis rats, one million synovial MSCs were injected into the knee joint every week. Cartilage degeneration was evaluated with safranin-o staining after the first injection. To analyze cell kinetics or MSC properties, luciferase, LacZ, and GFP expressing synovial MSCs were used. To confirm the role of MSCs, species-specific microarray and PCR analyses were performed using human synovial MSCs.

RESULTS

Histological analysis for femoral and tibial cartilage showed that a single injection was ineffective but weekly injections had significant chondroprotective effects for 12 weeks. Histological and flow-cytometric analyses of LacZ and GFP expressing synovial MSCs revealed that injected MSCs migrated mainly into the synovium and most of them retained their undifferentiated MSC properties though the migrated cells rapidly decreased. In vivo imaging analysis revealed that MSCs maintained in knees while weekly injection. Species-specific microarray and PCR analyses showed that the human mRNAs on day 1 for 21 genes increased over 50-fold, and increased the expressions of PRG-4, BMP-2, and BMP-6 genes encoding chondroprotective proteins, and TSG-6 encoding an anti-inflammatory one.

CONCLUSION

Not single but periodic injections of synovial MSCs maintained viable cells without losing their MSC properties in knees and inhibited osteoarthritis (OA) progression by secretion of trophic factors.

Valence and electronic trap states of manganese in SrTiO3-based colossal permittivity barrier layer capacitors

Valence and trap level of manganese in the (Mn, Nb)-doped SrTiO₃ internal barrier layer capacitor was revealed by EELS and Q-DLTS, explaining macroscopic properties.

Synovial mesenchymal stem cells promote healing after meniscal repair in microminipigs

OBJECTIVE

The induction of synovial tissue to the meniscal lesion is crucial for meniscal healing. Synovial Mesenchymal stem cells (MSCs) are an attractive cell source because of their high proliferative and chondrogenic potentials. We examined whether transplantation of synovial MSCs promoted healing after meniscal repair of extended longitudinal tear of avascular area in a microminipig model.

DESIGN

Longitudinal tear lesion was made in medial menisci and sutured in both knees, and then a synovial MSC suspension was administered for 10 min only in unilateral knee. The sutured meniscus was evaluated morphologically and biomechanically at 2, 4, and 12 weeks. The behavior of transplanted MSCs was also examined.

RESULTS

The meniscal healing at 12 weeks was significantly better in the MSC group than in the control group; macroscopically, histologically and by T1rho mapping analysis. Transmission electron microscopic analysis demonstrated that the meniscus lesion was occupied by dense collagen fibrils only in the MSC group. Biomechanical analysis revealed that the tensile strength to failure of the meniscus higher in the MSC group than in the control group in each microminipig. Synovial tissue covered better along the superficial layer from the outer zone into the lesion of the meniscus in the MSC group at 2 and 4 weeks in each microminipig. Synovial MSCs labeled with ferucarbotran were detected in the meniscus lesion and adjacent synovium by MRI at 2 weeks.

CONCLUSION

Transplantation of synovial MSCs promoted healing after meniscal repair with induction of synovium into the longitudinal tear in the avascular zone of meniscus in pigs.