Short-term outcomes of laparoscopic and robotic distal gastrectomy for gastric cancer: Real-world evidence from a large-scale inpatient database in Japan

BACKGROUND AND OBJECTIVES

Robotic distal gastrectomy (RDG) has been widely performed throughout Japan since it became insured in 2018. This study aimed to evaluate the short-term outcomes of RDG and laparoscopic distal gastrectomy (LDG) for gastric cancer using real-world data.

METHODS

A total of 4161 patients who underwent LDG (n = 3173) or RDG (n = 988) for gastric cancer between April 2018 and October 2022 were identified through the Japanese Diagnosis Procedure Combination Database, which covers 42 national university hospitals. The primary outcome was postoperative in-hospital mortality rate. The secondary outcomes were postoperative complication rates, time to diet resumption, and postoperative length of stay (LOS).

RESULTS

In-hospital mortality and postoperative complication rates in the RDG group were comparable with those in the LDG group (0.1% vs. 0.0%, p = 1.000, and 8.7% vs. 8.2%, p = 0.693, respectively). RDG was associated with a longer duration of anesthesia (325 vs. 262 min, p < 0.001), similar time to diet resumption (3 vs. 3 days, p < 0.001), and shorter postoperative LOS (10 vs. 11 days, p < 0.001) compared with LDG.

CONCLUSIONS

RDG was performed safely and provided shorter postoperative LOS, since it became covered by insurance in Japan.

Glutamate-Sensing Genes Are Conserved among Populations Compared to Glutamate Metabolism Genes

INTRODUCTION

Glutamate is a representative taste molecule with an umami flavor and is a major nutrient found abundantly in nature. Furthermore, it plays a significant role in the human body as a key metabolic intermediate and neurotransmitter. Therefore, the divergence of glutamate functions among populations during their evolution is of particular interest with a hypothesis that the genetic variation can lead to understanding divergence in taste perception. To elucidate variation in glutamate applications and to deepen our understanding of taste perception, we examined the nucleotide diversity of genes associated with glutamate sensing and metabolism among human populations.

METHODS

We first established 67 genes related to glutamate sensing and metabolism based on the database and literature survey. Then, for those genes, we used a population genomics approach based on ten populations over 76,156 human genomes in the gnomAD database.

RESULTS

Statistical tests of means and medians of the minor allele frequencies did not show any significant difference among populations. However, we observed substantial differences between two functional groups, glutamate sensing and glutamate metabolism, in populations of Latino/admixed American, Ashkenazi Jewish, and Others. Interestingly, we could find significant differences between the African population and the East Asian population at the single nucleotide polymorphism level of glutamate metabolism genes, but no clear differences were noted in glutamate-sensing genes. These suggest that glutamate-sensing genes are under the functional constraint compared to glutamate metabolism genes.

CONCLUSION

Thus, glutamate-sensing genes and metabolism genes have a contrasting mode of the evolution, and glutamate-sensing genes are conservatively evolved, indicating its functional importance.

Increased mitochondria are responsible for the acquisition of gemcitabine resistance in pancreatic cancer cell lines

Pancreatic ductal adenocarcinoma has a particularly poor prognosis as it is often detected at an advanced stage and acquires resistance to chemotherapy early during its course. Stress adaptations by mitochondria, such as metabolic plasticity and regulation of apoptosis, promote cancer cell survival; however, the relationship between mitochondrial dynamics and chemoresistance in pancreatic ductal adenocarcinoma remains unclear. We here established human pancreatic cancer cell lines resistant to gemcitabine from MIA PaCa-2 and Panc1 cells. We compared the cells before and after the acquisition of gemcitabine resistance to investigate the mitochondrial dynamics and protein expression that contribute to this resistance. The mitochondrial number increased in gemcitabine-resistant cells after resistance acquisition, accompanied by a decrease in mitochondrial fission 1 protein, which induces peripheral mitosis, leading to mitophagy. An increase in the number of mitochondria promoted oxidative phosphorylation and increased anti-apoptotic protein expression. Additionally, enhanced oxidative phosphorylation decreased the AMP/ATP ratio and suppressed AMPK activity, resulting in the activation of the HSF1-heat shock protein pathway, which is required for environmental stress tolerance. Synergistic effects observed with BCL2 family or HSF1 inhibition in combination with gemcitabine suggested that the upregulated expression of apoptosis-related proteins caused by the mitochondrial increase may contribute to gemcitabine resistance. The combination of gemcitabine with BCL2 or HSF1 inhibitors may represent a new therapeutic strategy for the treatment of acquired gemcitabine resistance in pancreatic ductal adenocarcinoma.

[A Case of Conversion Surgery after Nivolumab Monotherapy as Third-Line Therapy for Advanced Gastric Cancer]

A 79-year-old man with unresectable advanced gastric cancer due to invasion to the pancreas and positive lavage cytology( T4b, N+, M1, CY1, cStage ⅣB; Japanese classification of gastric carcinoma, 15th edition)received standard chemotherapy, including 6 courses of S-1 plus cisplatin as first-line therapy and 2 courses of paclitaxel plus ramucirumab followed by 6 courses of paclitaxel monotherapy as second-line therapy. The primary lesion became PD with these treatments. Subsequently, nivolumab monotherapy was introduced as third-line therapy. After 9 courses, the primary tumor shrunk, and lavage cytology turned to negative on diagnostic laparoscopy. We judged that the tumor was resectable, and the patient underwent radical total gastrectomy and D2 lymphadenectomy as conversion surgery. The pathological stage was ypT3(SS), N0, M0, CY0, and the therapeutic effect was Grade 1b. R0 resection was accomplished. He has been alive without recurrence for 18 months after resection without adjuvant chemotherapy.

Cetuximab Enhances the Efficacy of MRTX1133, a Novel KRASG12D Inhibitor, in Colorectal Cancer Treatment

BACKGROUND/AIM

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) has remained undruggable for decades. KRAS has predominantly been used to evaluate the applicability of anti-Epidermal Growth Factor Receptor (EGFR) antibody drugs. However, various KRAS inhibitors have recently emerged. Unfortunately, KRAS inhibitors have not been effective against colorectal cancer. Therefore, this study aimed to determine the effects of MRTX1133, a novel KRASG12D inhibitor, in combination with an anti-EGFR antibody, cetuximab, on signal transduction and cell proliferation.

MATERIALS AND METHODS

The KRASG12D-mutated LS513 and KRAS wild-type CACO-2 human colon cancer cell lines were utilized. The KRASG12D mutation was stably transduced into the CACO-2 cells using a retrovirus. We evaluated the effects of the drugs using the CCK-8 assay and assessed the activity of proteins related to the MAPK pathway using western blotting.

RESULTS

We demonstrated that the administration of MRTX1133, a novel KRASG12D inhibitor, to KRASG12D-mutated colorectal cancer cells led to feedback activation of the ERK pathway via EGFR activation, inducing drug resistance. Intriguingly, when MRTX1133 was used in combination with cetuximab, KRASG12D-mutant colorectal cancer growth was effectively inhibited, both in vitro and in vivo.

CONCLUSION

The combination of MRTX1133 and cetuximab serves as a potential and promising therapeutic approach for colorectal cancer with KRASG12D mutation. KRASG12D is a frequent genetic mutation not only in colorectal cancer, but also in pancreatic and lung cancer, and the results of this study open new avenues for potential treatment of many cancer patients.

Impact of Oophorectomy on Survival and Improving Nutritional Status in Ovarian Metastasis from Colorectal Adenocarcinoma

INTRODUCTION

Ovarian metastasis of colorectal cancer is known to have a poor prognosis. This study aimed to elucidate the characteristics of patients who underwent oophorectomy for ovarian metastasis from colorectal cancer.

METHODS

This retrospective study included 16 patients who underwent oophorectomy for colorectal cancer metastasis to the ovary from January 2004 to December 2017. Improvement in patient's symptoms and pre- and postoperative changes in various nutritional and inflammatory indicators were assessed. Survival analysis and identification of prognostic factors were conducted with a median follow-up of 40.7 (5-109) months.

RESULTS

Of 16 patients, 12 had (75%) synchronous and 4 (25%) had metachronous metastasis. Fourteen patients were symptomatic but symptoms resolved postoperatively. Thirteen patients (81.3%) had ascites and 5 (31.3%) had pleural effusion on preoperative computed tomography that disappeared after surgery in all cases. The median value of prognostic nutritional factor was significantly increased postoperatively (36.0 [preoperatively] vs. 47.5, p < 0.0001). The median (interquartile range) values for lymphocyte-C-reactive protein ratio were 715.2 (110-2,607) preoperatively and 6,095.2 (1,612.3-14,431.8) postoperatively (p = 0.0214). The median survival of the entire cohort was 60.4 months. The 3-year survival rates for R0 + R1 and R2 cases were 83% and 24% (p = 0.018), respectively. Univariate analysis showed that R2 resection and low postoperative lymphocyte-C-reactive protein ratio were associated with poor prognosis.

CONCLUSIONS

Oophorectomy for ovarian metastasis from colorectal cancers was safely performed. It improved the patients' symptoms and nutritional status and may result in improved prognosis.

High SLC20A1 Expression Indicates Poor Prognosis in Prostate Cancer

BACKGROUND/AIM

High expression of solute carrier family 20 member 1 (SLC20A1) indicates poor clinical outcomes for patients with breast cancer subtypes treated with endocrine therapy and radiotherapy. However, the association between SLC20A1 expression and clinical outcomes in prostate cancer remains to be determined.

MATERIALS AND METHODS

Open-source datasets (The Cancer Genome Atlas prostate, Stand Up to Cancer-Prostate Cancer Foundation Dream Team, and The Cancer Genome Atlas PanCancer Atlas) were downloaded and analyzed. SLC20A1 expression was analyzed in prostate cancer and normal prostate tissue. Survival analysis using Kaplan-Meier curves and Cox regression analysis were performed to examine patient prognosis, as well as the effects of endocrine therapy and radiotherapy on high SLC20A1 expression in patients with prostate cancer.

RESULTS

SLC20A1 was higher in prostate cancer than in normal prostate tissues. High SLC20A1 expression predicted poor disease-free and progression-free survival. Following endocrine therapy, no significant difference in prognosis was observed between patients with high SLC20A1 and those with low SLC20A1 expression. However, following radiotherapy, high SLC20A1 expression tended to be associated with a poor clinical outcome.

CONCLUSION

SLC20A1 may serve as a prognostic biomarker for prostate cancer, and the recommended treatment for patients with high SLC20A1 expression is endocrine therapy.

MEK inhibitor and anti-EGFR antibody overcome sotorasib resistance signals and enhance its antitumor effect in colorectal cancer cells

The Kirsten rat sarcoma (KRAS) oncogene was "undruggable" until sotorasib, a KRAS^G12C selective inhibitor, was developed with promising efficacy. However, inhibition of mutant KRAS in colorectal cancer cells (CRC) is ineffective due to feedback activation of MEK/ERK downstream of KRAS. In this study, we screened for combination therapies of simultaneous inhibition to overcome sotorasib resistance using our previously developed Mix Culture Assay. We evaluated whether there was an additive effect of sotorasib administered alone and in combination with two or three drugs: trametinib, a MEK inhibitor, and cetuximab, an anti-epidermal growth factor receptor (EGFR) antibody. The MAPK pathway was reactivated in KRAS^G12C-mutated cell lines treated with sotorasib alone. Treatment with KRAS and MEK inhibitors suppressed the reactivation of the MAPK pathway, but upregulated EGFR expression. However, the addition of cetuximab to this combination suppressed EGFR reactivation. This three-drug combination therapy resulted in significant growth inhibition in vitro and in vivo. Our data suggest that reactive feedback may play a key role in the resistance signal in CRC. Simultaneously inhibiting KRAS, MEK, and EGFR is a potentially promising strategy for patients with KRAS^G12C-mutated CRC.

Optimal Administration of Glycyrrhizin Avoids Pharmacokinetic Interactions With High-dose Methotrexate and Exerts a Hepatoprotective Effect

BACKGROUND/AIM

Glycyrrhizin (GZ) is widely used to treat high-dose methotrexate (MTX)-induced liver dysfunction. However, in a previous in vivo study, we showed that simultaneous administration of both drugs increased the plasma concentration of MTX and exacerbated hepatic injuries. In this study, we investigated the optimal dosing interval in rats to avoid the interaction between high-dose MTX and GZ and to demonstrate the inherent hepatoprotective effect of GZ.

MATERIALS AND METHODS

Male Wistar rats were treated with high-dose MTX (2,000 mg/kg) alone, with concomitant administration of 100 mg/kg GZ or GZ administered 3, 6, and 24 h before MTX administration. Plasma concentrations of MTX, alanine aminotransferase, aspartate aminotransferase, and total bilirubin were measured.

RESULTS

The plasma concentration and half-life of methotrexate were significantly increased after concomitant administration of GZ, or when GZ was administered 3 h before MTX administration, compared with MTX alone, increasing hepatic enzyme levels. However, when GZ was administered 6 and 24 h before MTX administration, the levels were not significantly different from those of MTX alone and showed a tendency to decrease MTX-induced liver injury. These results suggest that the pharmacokinetic interaction between GZ and MTX could be avoided and the hepatoprotective effect of GZ could be achieved by an optimal dosing regimen, using the half-life of GZ as an indicator.

CONCLUSION

When using high-dose MTX in combination with GZ, the administration intervals should be considered to avoid unwanted interactions and to achieve the GZ hepatoprotective effect.

Importance of intraoperative indocyanine green imaging in the management of non-occlusive mesenteric ischemia: a case report

BACKGROUND

Non-obstructive intestinal ischemia (NOMI) is caused by intestinal vascular spasm and has a poor prognosis if not diagnosed and treated early. Indocyanine green (ICG) fluorescence imaging has been reported to be useful for the intraoperative assessment of the extent of intestinal resection required for NOMI. Few reports have described massive intestinal bleeding after conservative management of NOMI. We report a case of NOMI with massive postoperative bleeding from the site of an ICG contrast defect found before the initial surgery.

CASE PRESENTATION

A 47-year-old woman with hemodialysis-dependent chronic kidney disease presented complaining of severe abdominal pain. A computed tomography scan showed portal gas and dilation of the small intestine, leading to a diagnosis of NOMI and subsequent emergency surgery. At the time of initial surgery, the contrast effect of ICG was slightly reduced, showing a granular distribution in the ascending colon to cecum (fine grain pattern) and significantly reduced in parts of the terminal ileum except around blood vessels (perivascular pattern). However, there was no obvious gross necrosis of the serosal surface, and the intestinal tract was not resected. The acute postoperative course was uneventful; however, the patient went into shock on the 24th postoperative day due to massive, small intestinal bleeding, and emergency surgery was performed. The bleeding originated from the section of the ileum that had complete loss of ICG contrast effect before the initial surgery. A right hemicolectomy with the terminal ileum resection was performed, and an ileo-transverse anastomosis was performed. The second post-operative course was uneventful.

CONCLUSIONS

We report a case of delayed hemorrhage of the ileum shown to have poor blood flow on ICG imaging at the initial surgery. Intraoperative ICG fluorescence imaging is useful in assessing the degree of intestinal ischemia for NOMI. When patients with NOMI are followed up without surgery, complications such as bleeding should be noted.

RhoA G17E/Vav1 Signaling Induces Cancer Invasion via Matrix Metalloproteinase-9 in Gastric Cancer

BACKGROUND

RAS homolog family member A (RhoA), a member of the Rho family of small GTPases, and Vav1, a guanine nucleotide exchange factor for Rho family GTPases, have been reported to activate pathways related to the actin cytoskeleton and regulation of cell shape, attachment, and motility. The interaction between these molecules in lymphoma is involved in malignant signaling, but its function in epithelial malignancy is unknown. Here, we investigated the malignant signal of mutant RhoA in gastric cancer and demonstrated the potential of RhoA G17E/Vav1 as a therapeutic target for diffuse gastric cancer.

METHODS

The RhoA mutants R5W, G17E, and Y42C were retrovirally transduced into the gastric cancer cell line MKN74. The stably transduced cells were used for morphology, proliferation, and migration/invasion assays in vitro. MKN74 cells stably transduced with ectopic wild-type RhoA and mutant RhoA (G17E) were used in a peritoneal xenograft assay.

RESULTS

The RhoA mutations G17E and Y42C induced morphological changes in MKN74. G17E induced Vav1 expression at the mRNA and protein levels and promoted the migration and invasion of MKN74. An RNA interference assay of Vav1 revealed that RhoA G17E enhanced cancer cell invasion via Vav1. Furthermore, immunoprecipitation revealed that Vav1 and RhoA G17E specifically bind and function together through matrix metalloproteinase -9. In a peritoneal xenograft model of nude mice, RhoA G17E promoted peritoneal dissemination, whereas Vav1 knockdown suppressed it.

CONCLUSION

Overall, our findings indicate that RhoA G17E is associated with Vav1 and promoted cancer invasion via matrix metalloproteinase -9 in gastric cancer cells. Thus, RhoA G17E/Vav1 signaling in diffuse gastric cancer may be a useful therapeutic target.

Gastric glomus tumor resection using laparoscopic endoscopic cooperative surgery: A case report

Gastric glomus tumors are rare submucosal mesenchymal neoplasms that are difficult to diagnose preoperatively. We present a case of a 60-year-old woman who was diagnosed with a gastric glomus tumor using endoscopic ultrasonography-guided fine-needle aspiration biopsy. The tumor was successfully resected with laparoscopic endoscopic cooperative surgery (LECS). LECS could be an effective method for the resection of gastric glomus tumors.

Risk factors for umbilical incisional hernia after laparoscopic colorectal surgery

BACKGROUND

Laparoscopic colorectal surgery (LCRS) requires a small laparotomy at the umbilicus. The wound is small and inconspicuous, but if the patient develops an umbilical incisional hernia (UIH), the wound is visible and the patient suffers from symptoms of discomfort. However, the incidence of UIH after LCRS and its risk factors are not well understood. The purpose of this study was to investigate the risk factors for UIH after LCRS for colorectal cancer.

METHODS

This was a single-centre retrospective study of 135 patients with colorectal cancer, conducted at our hospital from April 2013 to March 2019. The diagnosis of UIH was based on computed tomography and physical examination findings. Preoperative patient data such as enlargement of the umbilical orifice (EUO), subcutaneous fat thickness (SFT) and intraperitoneal thickness (IPT) were collected and analysed using univariate and multivariate analyses for the presence of risk factors for UIH.

RESULTS

A total of 135 patients who underwent LCRS were analysed. The incidence of UIH was 20.7%. Univariate analysis revealed significantly high body mass index (BMI) ≥ 25 (P = 0.032), EUO (P < 0.001), SFT ≥18 mm (P = 0.011), and IPT ≥61 mm (P < 0.01) in the UIH group. Multivariate analysis revealed significant differences in EUO (P < 0.001), SFT ≥18 mm (P = 0.046) and IPT ≥61 mm (P = 0.022).

CONCLUSION

EUO was the most important risk factor for UIH, followed by IPT and SFT. These findings are predictive indicators of the development of UIH after LCRS and can be assessed objectively and easily with preoperative computed tomography.

Predicting new-onset heart failure hospitalization of patients with atrial fibrillation: development and external validations of a risk score

Background

Atrial fibrillation (AF) is a well-known risk factor for heart failure (HF), and HF development as a complication of AF is associated with a decline in the quality of life and poor prognosis. However, unlike thrombotic events, incidence of HF in patients with AF has not changed for decades, and a preventive strategy has yet to be developed.

Purpose

We sought to develop a risk model for new-onset HF admission in patients with AF and without a history of HF. Additionally, we attempted to externally validate the developed risk model.

Methods

We utilized two multicenter, prospective, observational registries of AF and analyzed the patients without a history of AF. One of which is defined as a derivation cohort, which included 2,857 patients, and the other is defined as a validation cohort, which included 2,516 patients. We developed a risk model by selecting variables with regularized regression and weighing coefficients by Cox regression analysis with the derivation cohort. The external validity was tested in the validation cohort.

Results

During the follow-up period, 148 patients (5.2%) in the derivation cohort and 104 patients (4.1%) in the validation cohort developed HF during the median follow-up period of 1,396 (interquartile range [IQR]: 1,078–1,820) days and 1,168 (IQR: 844–1,309) days, respectively. In the derivation cohort, four predictors (age, hemoglobin, serum creatinine, and log-transformed brain natriuretic peptide) were identified as potential risk factors for HF development. The developed risk model showed good discrimination and calibration in both the derivation (area under the curve [AUC], 0.77 [95% confidence interval (CI) 0.73–0.81]; Hosmer-Lemeshow test, P=0.257) and validation cohorts (AUC: 0.76 [95% CI 0.72–0.81]; Hosmer-Lemeshow test, P=0.475). Considering death not due to HF as a competing risk, the cumulative incidence curves for HF admission stratified by the risk score were generated, which showed higher HF hospitalization rate for the higher risk score categories.

Conclusion

The newly developed risk model with four readily available clinical characteristics and biomarkers performed well in the prediction of new-onset HF admission of patients with AF in both derivation and validation cohort.

Funding Acknowledgement

Type of funding sources: None.

High-frequency ultrasound exposure improves depressive-like behavior in an olfactory bulbectomized rat model of depression

OBJECTIVES

According to previous studies, ultrasound exposure appears to be a noninvasive method for modulating brain activity related to cognition and consciousness; however, its effects on emotional states remain unclear. Therefore, an animal model is required in which the effects and effect mechanisms of ultrasound exposure can be investigated. Thus, we used olfactory bulbectomized rats as an animal model of depression and investigated their emotional state following ultrasound exposure.

METHODS

In male Wistar/ST olfactory bulbectomized rats, hyperemotionality was evaluated according to hyperemotionality scoring and the scores before and after 24-h ultrasound exposure were compared. Elevated plus maze (EPM) tests were also conducted after 24-h ultrasound exposure, and blood samples were collected in which plasma corticosterone concentrations were measured.

RESULTS

Following exposure to high-frequency (~50 kHz) ultrasound vocalizations (USVs) associated with the pleasant emotions of rats, the hyperemotionality scores of olfactory bulbectomized rats were significantly reduced. Additionally, the latency of the first entry into the open arm of the EPM was significantly decreased in USV-exposed olfactory bulbectomized rats, as were their plasma corticosterone levels. Furthermore, artificial ultrasound (50 kHz) at a similar frequency to that of USV also significantly decreased the hyperemotionality score of olfactory bulbectomized rats.

CONCLUSIONS

Ultrasound exposure improved depressive-like behavior in olfactory bulbectomized rats and reduced their plasma corticosterone levels. Thus, we recommend the use of olfactory bulbectomized rats as an animal model for investigating the effects and effect mechanisms of ultrasound exposure.

High SLC20A1 Expression Is Associated With Poor Prognosis for Radiotherapy of Estrogen Receptor-positive Breast Cancer

BACKGROUND/AIM

Radiotherapy is one of the main treatments for estrogen receptor-positive (ER+) breast cancer. However, in some ER+ breast cancer cases, radiotherapy is insufficient to inhibit progression and there is a lack of markers to predict radiotherapy insensitivity. Solute carrier family 20 member 1 (SLC20A1) is a sodium/inorganic phosphate symporter, which has been proposed to be a viable prognostic marker for luminal A and B types of ER+ breast cancer. The present study examined the possibility of SLC20A1 as a novel biomarker for the prediction of radiotherapy efficiency.

PATIENTS AND METHODS

The Molecular Taxonomy of Breast Cancer International Consortium dataset was downloaded from cBioportal and the prognosis of patients with high SLC20A1 expression (SLC20A1 ^high ) was compared with that of patients with low SLC20A1 expression, without or with radiotherapy and tumor stages I, II, and III, using the Kaplan-Meier method and multivariate Cox regression analyses of disease-specific and relapse-free survival.

RESULTS

Patients in the SLC20A1 ^high group with radiotherapy showed poor clinical outcomes in both luminal A and luminal B breast cancers. Furthermore, in luminal A breast cancer at tumor stage I, patients in the SLC20A1 ^high  group with radiotherapy also showed poor clinical outcomes. Therefore, these results suggest that radiotherapy is insufficient for patients in the SLC20A1 ^high group for both luminal A and B types, and especially for the luminal A type at tumor stage I.

CONCLUSION

SLC20A1 can be used as a prognostic marker for the prediction of the efficacy of radiotherapy for luminal A and luminal B breast cancers.

Repeat procedures and reconnection rates after cryoballoon PVI with phrenic nerve injury

Funding Acknowledgements

Type of funding sources: None.

Aims

Cryoballoon (CB) based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury which is leading to premature abortion of the freeze cycle. Here we analysed repeat procedures and reconnection rates after CB-based PVI and phrenic nerve injury in a large-scale population. Due to the fact that the freezing process was prematurely interrupted the data may offer unique findings in optimizing the CB dosing protocols.

Methods and Results

In the YETI registry a total of 17356 patients underwent CB-based PVI in 33 centers and 731 (4.2%) patients experienced phrenic nerve injury. A total of 111 / 731 (15.2%) patients received a repeat procedure utilizing a 3D mapping system due to AF recurrence. In 94/111 (84.7%) of patients data on repeat procedures was available. During their initial PVI procedures, phrenic nerve injury occurred during treatment of RSPV (n=80), RIPV (n=13) and LSPV (n=1). A total of 89/94 (94.7%) target PVs have been isolated during the initial PVI (RSPV: 75/80, 94%; RIPV: 13/13; 100%; LSPV: 1/1; 100%). The mean freezing time was 127±46s and the mean minimal temperature was -49±7°C. During the repeat procedures 67 of initially 89 isolated PVs showed persistent isolation (75%, for RSPV: 55/75; 73%; RIPV: 11/13; 85%; LSPV: 1/1; 100%).

Conclusion

In patients initially treated by CB-based PVI with interruption of the freezing due to phrenic nerve injury, a high rate of durable isolated PVs has been detected at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures

The function of SARS-CoV-2 spike protein is impaired by disulfide-bond disruption with mutation at cysteine-488 and by thiol-reactive N-acetyl-cysteine and glutathione

Viral spike proteins play important roles in the viral entry process, facilitating attachment to cellular receptors and fusion of the viral envelope with the cell membrane. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein binds to the cellular receptor angiotensin converting enzyme-2 (ACE2) via its receptor-binding domain (RBD). The cysteine residue at position 488, consisting of a disulfide bridge with cysteine 480 is located in an important structural loop at ACE2-binding surface of RBD, and is highly conserved among SARS-related coronaviruses. We showed that the substitution of Cys-488 with alanine impaired pseudotyped SARS-CoV-2 infection, syncytium formation, and cell-cell fusion triggered by SARS-CoV-2 spike expression. Consistently, in vitro binding of RBD and ACE2, spike-mediated cell-cell fusion, and pseudotyped viral infection of VeroE6/TMPRSS2 cells were inhibited by the thiol-reactive compounds N-acetylcysteine (NAC) and a reduced form of glutathione (GSH). Furthermore, we demonstrated that the activity of variant spikes from the SARS-CoV-2 alpha and delta strains were also suppressed by NAC and GSH. Taken together, these data indicate that Cys-488 in spike RBD is required for SARS-CoV-2 spike functions and infectivity, and could be a target of anti-SARS-CoV-2 therapeutics.

Involvement of autophagy in the maintenance of rat intervertebral disc homeostasis: an in-vitro and in-vivo RNA interference study of Atg5

OBJECTIVE

In the largest avascular low-nutrient intervertebral disc, resident cells would utilize autophagy, a stress-response survival mechanism by self-digestion and recycling wastes. Our goal was to elucidate the involvement of autophagy in disc homeostasis through RNA interference of autophagy-related gene 5 (Atg5).

DESIGN

In vitro, small interfering RNAs (siRNAs) targeting autophagy-essential Atg5 were transfected into rat disc cells. Cell viability with levels of autophagy including Atg5 expression, apoptosis, and senescence was assessed under serum starvation and/or pro-inflammatory interleukin-1 beta (IL-1β) stimulation. In vivo, time-course autophagic flux was monitored following Alexa Fluor® 555-labeled Atg5-siRNA injection into rat tail discs. Furthermore, 24-h temporary static compression-induced disruption of Atg5 siRNA-injected discs was observed by radiography, histomorphology, and immunofluorescence.

RESULTS

In disc cells, three different Atg5 siRNAs consistently suppressed autophagy with Atg5 protein knockdown (mean 44.4% [95% confidence interval: -51.7, -37.1], 51.5% [-80.5, -22.5], 62.3% [-96.6, -28.2]). Then, Atg5 knockdown reduced cell viability through apoptosis and senescence not in serum-supplemented medium (93.6% [-0.8, 21.4]) but in serum-deprived medium (66.4% [-29.8, -8.6]) further with IL-1β (44.5% [-36.9, -23.5]). In disc tissues, immunofluorescence detected intradiscal signals for the labeled siRNA even at 56-d post-injection. Immunoblotting found 56-d autophagy suppression with prolonged Atg5 knockdown (33.2% [-52.8, -5.3]). With compression, Atg5 siRNA-injected discs presented radiographic height loss ([-43.9, -0.8]), histological damage ([-5.5, -0.2]), and immunofluorescent apoptosis ([2.2, 22.2]) and senescence ([4.1, 19.9]) induction compared to control siRNA-injected discs at 56 d.

CONCLUSIONS

This loss-of-function study suggests Atg5-dependent autophagy-mediated anti-apoptosis and anti-senescence. Autophagy could be a molecular therapeutic target for degenerative disc disease.

Alfaxalone improved in acute stress-induced tactile hypersensitivity and anxiety-like behavior in mice

Stress has been shown to affect brain activity and exert potent and complex modulatory effects on pain. Several behavioral tests have shown that acute stress produces hyperalgesia, depending on the stress conditions. In the present study, we investigated the effects of single restraint stress on the tactile threshold and anxiety sensitivity in mice. Mice were evaluated for the tactile threshold using von Frey filaments and for anxiety sensitivity using the elevated plus maze (EPM) test. Tactile thresholds were lowered by both 2 and 4 hour of restraint stress, but anxiety-like behaviors were observed only after 4 hour of restraint stress in the EPM test. In addition, we found that alfaxalone, which is a positive allosteric modulator of the γ-aminobutyric acid (GABA)_A receptor, prevented restraint stress-induced hyperalgesia-like and anxiety-like behaviors. These results indicate that GABAergic function appears to be critical in the regulation of physical stress-induced hyperalgesia and anxiety.

A case of appendiceal ganglioneuroma in neurofibromatosis type 1

BACKGROUND

Neurofibromatosis type 1 is an autosomal dominant inherited disease associated with multiple skin neurofibromas or other neurogenic tumors, such as nodular plexiform neurinoma or cerebrospinal tumor. Gastrointestinal stromal tumors are often complicated in patients with neurofibromatosis type 1, although involvement of the appendix is rare, and there have been few reports of appendiceal ganglioneuroma.

CASE PRESENTATION

The patient was a 29-year-old man diagnosed with neurofibromatosis type 1 based on physical findings and his family history. During the follow-up of neurofibromatosis, computed tomography was performed to detect neurological tumors, such as neurofibromas in the brain, spinal cord, and gastrointestinal tract. Computed tomography showed a markedly thickened appendix wall, and an appendiceal tumor was suspected. Laparoscopic appendectomy was performed, and a 50 × 35 mm appendiceal submucosal tumor was resected with a negative resection margin. At histopathological examination, the tumor was diagnosed as ganglioneuroma; it showed short spindle-shaped cells and ganglion cells diffusely infiltrated into the proper muscle layer and fibrous tissue that grew around nerve cells. The patient was discharged on the 5th postoperative day without postoperative complications and was doing well at 13 months following the operation.

CONCLUSIONS

Gastrointestinal stromal tumor and neurofibroma are the most common gastrointestinal tumors associated with neurofibromatosis type 1, but ganglioneuroma of the appendix is rare. Appendiceal neurogenic tumors should be considered in patients with neurofibromatosis type 1, and surgical resection is necessary because of the risk of malignancy.

Identification of novel heat shock-induced long non-coding RNA in human cells

The heat-shock response is a crucial system for survival of organisms under heat stress. During heat-shock stress, gene expression is globally suppressed, but expression of some genes, such as chaperone genes, is selectively promoted. These selectively activated genes have critical roles in the heat-shock response, so it is necessary to discover heat-inducible genes to reveal the overall heat-shock response picture. The expression profiling of heat-inducible protein-coding genes has been well-studied, but that of non-coding genes remains unclear in mammalian systems. Here, we used RNA-seq analysis of heat shock-treated A549 cells to identify seven novel long non-coding RNAs that responded to heat shock. We focussed on CTD-2377D24.6 RNA, which is most significantly induced by heat shock, and found that the promoter region of CTD-2377D24.6 contains the binding site for transcription factor HSF1 (heat shock factor 1), which plays a central role in the heat-shock response. We confirmed that HSF1 knockdown cancelled the induction of CTD-2377D24.6 RNA upon heat shock. These results suggest that CTD-2377D24.6 RNA is a novel heat shock-inducible transcript that is transcribed by HSF1.

NF-kB decoy oligodeoxynucleotide preserves disc height in a rabbit anular-puncture model and reduces pain induction in a rat xenograft-radiculopathy model

While it is known that the degenerated intervertebral disc (IVD) is one of the primary reasons for low-back pain and subsequent need for medical care, there are currently no established effective methods for direct treatment. Nuclear factor-κB (NF-κB) is a transcription factor that regulates various genes' expression, among which are inflammatory cytokines, in many tissues including the IVD. NF-κB decoy is an oligodeoxynucleotide containing the NF-κB binding site that entraps NF-κB subunits, resulting in suppression of NF-κB activity. In the present preclinical study, NF-κB decoy was injected into degenerated IVDs using the rabbit anular-puncture model. In terms of distribution, NF-κB decoy persisted in the IVDs up to at least 4 weeks after injection. The remaining amount of NF-κB decoy indicated that it fit a double-exponential-decay equation. Investigation of puncture-caused degeneration of IVDs showed that NF-κB decoy injection recovered, dose-dependently, the reduced disc height that was associated with reparative cell cloning and morphological changes, as assessed through histology. Gene expression, by quantitative real-time polymerase chain reaction (qRT-PCR), showed that NF-κB decoy attenuated inflammatory gene expression, such as that of interleukin-1 and tumor necrosis factor-α, in rabbit degenerated IVDs. NF-κB decoy also reduced the pain response as seen using the "pain sensor" nude rat xenograft-radiculopathy model. This is the first report demonstrating that NF-κB decoy suppresses the inflammatory response in degenerated IVDs and restores IVD disc height loss. Therefore, the intradiscal injection of NF-κB decoy may have the potential as an effective therapeutic strategy for discogenic pain associated with degenerated IVDs.

Usefulness of a 3D-printing air sampler for capturing live airborne bacteria and exploring the environmental factors that can influence bacterial dynamics

We created a handmade 3D-printed air sampler to effectively collect live airborne bacteria, and determined which environmental factors influenced the bacteria. Bacterial colony forming units (CFUs) in the air samples (n=37) were monitored by recording the environmental changes occurring over time, then determining the presence/absence of correlations among such changes. The bacterial CFUs changed sharply and were significantly correlated with the DNA concentrations, indicating that the captured bacteria made up most of the airborne bacteria. Spearman's rank correlation analysis revealed significant correlations between the bacterial CFU values and some environmental factors (humidity, wind speed, insolation, and 24-h rainfall). Similarly the significant associations of CFU with humidity and wind speed were also found by multiple regression analysis with box-cox transformation. Among our panel of airborne bacteria (952 strains), 70 strains were identified as soil-derived Bacillus via the production of Escherichia coli- and Staphylococcus aureus-growth inhibiting antibiotics and by 16S rDNA typing. Soil-derived protozoa were also isolated from the air samples. We conclude that the airborne bacteria mainly derived from soil can alter in number according to environmental changes. Our sampler, which was created by easy-to-customize 3D printing, is a useful device for understanding the dynamics of live airborne bacteria.

Concomitant Use of High-dose Methotrexate and Glycyrrhizin Affects Pharmacokinetics of Methotrexate, Resulting in Hepatic Toxicity

BACKGROUND/AIM

High-dose methotrexate is a therapy for acute leukemia, malignant lymphoma, and osteosarcoma. Glycyrrhizin has been used to treat hepatic dysfunction caused by high-dose methotrexate. However, few studies have investigated the interaction between glycyrrhizin and high-dose methotrexate.

MATERIALS AND METHODS

Male Wistar rats were treated with high-dose methotrexate (500 or 1,000 mg/kg) alone, or with co-administration of 100 mg/kg glycyrrhizin. Plasma concentrations of methotrexate, alanine aminotransferase, aspartate aminotransferase, and total bilirubin were measured.

RESULTS

At both methotrexate doses, the blood concentration of methotrexate was significantly increased and total clearance was significantly reduced using co-administration of glycyrrhizin compared with methotrexate alone, which led to increased levels of hepatic enzymes. These results suggest that glycyrrhizin significantly increases the plasma level and delays the clearance of methotrexate, resulting in hepatic toxicity.

CONCLUSION

The concomitant use of methotrexate and glycyrrhizin should be considered with caution.

Vitamin D Deficiency-induced Osteomalacia in a Patient with Anorexia Nervosa

A 48-year-old woman with a 9-year-history of anorexia nervosa (AN) was admitted complaining of generalized bone pain. Blood tests showed hypocalcemia and hyperphosphatasemia, and a radiological survey revealed multiple rib fractures, suggesting complication with osteomalacia. Two years earlier, she had undergone subtotal colectomy for colon cancer. Her serum 25-hydroxy vitamin D concentration was below the detectable level. In addition to a poor nutritional intake and insufficient sun exposure, malabsorption of fat-soluble substances in the intestine and phosphate loss from the kidneys might have contributed to the development of her osteomalacia.

Drug sensitivity profile of minor KRAS mutations in colorectal cancer using mix culture assay: The effect of AMG-510, a novel KRAS G12C selective inhibitor, on colon cancer cells is markedly enhanced by the combined inhibition of MEK and BCL-XL

Colorectal cancer with a Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) gene mutation is considered to be resistant to anti-EGFR agents. G12D is the most common KRAS mutation in colorectal cancer, followed by G12V and G13D. According to clinical and basic research data, patients with colorectal cancer exhibiting G12D and G12V KRAS mutations are resistant to anti-EGFR agents; however, this is not true of G13D and other minor mutations, which are still not well understood. The current study focused on minor KRAS mutations (G12A, G12C, G12S, Q61H and A146T) and evaluated whether these were resistant to anti-EGFR antibodies using a mix culture assay. The results demonstrated that all KRAS mutations, including minor mutations, were resistant to two anti-EGFR agents: Cetuximab and panitumumab. The combined effect of MEK and BCL-XL inhibition on colorectal cancer cells with KRAS minor mutations were subsequently evaluated. The combined effect of MEK and BCL-XL inhibitors was confirmed in all KRAS minor mutations. The sensitivity of AMG510, a novel KRAS G12C selective inhibitor, was also assessed. The mix culture assay revealed that AMG510 selectively exerted an antitumor effect on colon cancer cells with a G12C KRAS mutation. The combination of MEK and BCL-XL inhibition markedly enhanced the effect of AMG510 in colon cancer cells. The current study suggested that AMG510 may have potential clinical use in combination with MEK and BCL-XL inhibitors in the treatment of patients with colorectal cancer exhibiting the G12C KRAS mutation.

Expressions of conventional vitellogenin and vitellogenin-like A in worker brains are associated with a nursing task in a ponerine ant

In eusocial insect colonies, non-reproductive workers often perform different tasks. Tasks of an individual worker are shifted depending on various factors, e.g., age and colony demography. Although a vitellogenin (Vg) gene play regulatory roles in both reproductive and non-reproductive division of labours in a honeybee, it has been shown that the insect Vg underwent multiple gene duplications and sub-functionalisation, especially in apical ant lineages. The regulatory roles of duplicated Vgs were suggested to change evolutionarily among ants, whereas such roles in phylogenetically basal ants remain unclear. Here, we examined the expression patterns of conventional Vg (CVg), Vg-like A, Vg-like B and Vg-like C, as well as Vg receptor, during the task shift in an age-dependent manner and under experimental manipulation of colony demography in a primitive ant Diacamma sp. Expressions of CVg and Vg-like A in a brain were associated with a nursing task. It is suggested that associations of brain expressions of these Vgs with worker tasks were acquired in the basal ant lineage, and that such Vg functions could have sub-functionalised in the derived ant lineage.

Respiratory Sarcopenia and Sarcopenic Respiratory Disability: Concepts, Diagnosis, and Treatment

The condition of muscle fiber atrophy and weakness that occurs in respiratory muscles along with systemic skeletal muscle with age is known as respiratory sarcopenia. The Japanese Working Group of Respiratory Sarcopenia of the Japanese Association of Rehabilitation Nutrition narratively reviews these areas, and proposes the concept and diagnostic criteria. We have defined respiratory sarcopenia as "whole-body sarcopenia and low respiratory muscle mass followed by low respiratory muscle strength and/or low respiratory function." Respiratory sarcopenia can be caused by various factors such as aging, decreased activity, undernutrition, disease, cachexia, and iatrogenic causes. We have also created an algorithm for diagnosing respiratory sarcopenia. Respiratory function decreases with age in healthy older people, along with low respiratory muscle mass and strength. We have created a new term, "Presbypnea," meaning a decline in respiratory function with aging. Minor functional respiratory disability due to aging, such as that indicated by a modified Medical Research Council level 1 (troubled by shortness of breath when hurrying or walking straight up hill), is an indicator of presbypnea. We also define sarcopenic respiratory disability as "a disability with deteriorated respiratory function that results from respiratory sarcopenia." Sarcopenic respiratory disability is diagnosed if respiratory sarcopenia is present with functional disability. Cases of respiratory sarcopenia without functional disability are diagnosed as "at risk of sarcopenic respiratory disability." Functional disability is defined as a modified Medical Research Council grade of 2 or more. Rehabilitation nutrition, treatment that combines rehabilitation and nutritional management, may be adequate to prevent and treat respiratory sarcopenia and sarcopenic respiratory disability.

Cardioprotection using strain-guided management of potentially cardiotoxic cancer therapy: 1 year results of the SUCCOUR trial

Background

Conventional criteria for diagnosis of chemotherapy-related cardiac dysfunction (CTRCD) are dependent on the recognition of heart failure (HF) symptoms and/or changes in LVEF. However, the low sensitivity of EF for minor changes in LV function may delay initiation of cardio-protective therapy (CPT). Global longitudinal strain (GLS) is a robust and sensitive marker of LV dysfunction (LVD), but existing observational data are insufficient to justify changing the diagnostic criteria for CTRCD.

Purpose

To identify whether GLS guidance of CPT would improve cardiac function of at risk patients undergoing potentially cardiotoxic chemotherapy, compared with usual care.

Methods

In this international multicenter prospective randomized controlled trial, 331 pts from 23 international sites taking anthracyclines with another risk factor for HF were randomly allocated into 166 undergoing GLS-guided (CPT for &gt;12% relative reduction in GLS using Echopac software) and 165 EF-guided (CPT for &gt;10% absolute reduction of EF). Pts were followed over 1 year for the primary end-point (ΔEF) with 3D echo (3DE); 2D echo (2DE) was used when 3D images were unsuitable for measurement. Development of CTRCD (EF reduction of 10% to &lt;55%) was a secondary endpoint.

Results

Of 331 randomized patients, 24 withdrew before follow-up imaging was performed (2 died, and rest withdrew or were lost to follow-up). Among 307 patients (age 54±12 years, 94% women) with follow-up 1.0±0.2 years, 277 had breast cancer, 30 had lymphoma/leukemia. HF risk factors were prevalent: 89 (29%) had hypertension and 39 (13%) had diabetes mellitus. The most common chemotherapy regimen during this study was the combination of anthracycline and trastuzumab. The baseline 3D LVEF was 61±5%, and GLS was −20.8±3.2%. At 1 year follow-up, 31 (10%) met CTRCD and was reduced in the GLS-guided arm (Table 1), although new LV dysfunction (EF&lt;55%) and change of EF were not different.

Conclusion

In this international multicentre trial, the incidence of CTRCD was reduced by strain-guided cardioprotection. Although the final EF and the number of pts developing EF &lt;55% was not altered by strain-guided therapy, this reduces meaningful reduction of EF to the abnormal range. The results support the use of GLS in surveillance for CTRCD.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): General Electric Medical Systems

Exposure of the cryptic de-adhesive site FNIII14 in fibronectin molecule and its binding to membrane-type eEF1A induce migration and invasion of cancer cells via β1-integrin inactivation

Cell migration is a highly coordinated process that involves not only integrin-mediated adhesion but also de-adhesion. We previously found that a cryptic de-adhesive site within fibronectin molecule, termed FNIII14, weakens cell adhesion to the extracellular matrix by inactivating β1-integrins. Surprisingly, eukaryotic translation elongation factor-1A (eEF1A), an essential factor during protein biosynthesis, was identified as a membrane receptor that mediates the de-adhesive effect of FNIII14. Here, we demonstrate that FNIII14-mediated de-adhesion causes enhanced migration and invasion in two types of highly invasive/metastatic cancer cells, resulting in the initiation of metastasis. Both in vitro migration and invasion of highly invasive human melanoma cell line, Mum2B, were inhibited by a matrix metalloproteinase (MMP)-2/9 inhibitor or a function-blocking antibody against FNIII14 (anti-FNIII14 Ab), suggesting that MMP-mediated exposure of the cryptic de-adhesive site FNIII14 was responsible for Mum2B cell migration and invasion. The MMP-induced FNIII14 exposure was also shown to be functional in the migration and invasion of highly metastatic mouse breast cancer cell line 4T1. Overexpression and knockdown experiments of eEF1A in Mum2B cells revealed that the migration and invasion were dependent on the membrane levels of eEF1A. In vivo experiments using tumor xenograft mouse models derived from Mum2B and 4T1 cell lines showed that the anti-FNIII14 Ab has a significant anti-metastatic effect. Thus, these results provide novel insights into the regulation of cancer cell migration and invasion and suggest promising targets for anti-metastasis strategies.

Effects of PCSK9 inhibitor on adverse limb outcomes in patients with critical limb ischemia

Background

The proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9-I), evolocumab, reduced the risk of cardiovascular event in patients with peripheral artery disease in FOURIER trial. However, the effects of evolocumab on favorable limb outcomes in patients with critical limb ischemia (CLI) is still unclear.

Purpose

The aim of this study was to evaluate the impacts of evolocumab on favorable limb outcomes and lipid profile in patients with CLI.

Methods

This was a single center, prospective observational study. A total of 39 patients with CLI were enrolled between November 2016 to May 2019. The subjects were divided into 2 groups based on evolocumab administration: evolocumab-treated group: E group (mean 69.4±11.7 years, n=14) and evolocumab non-treated group: Non-E group (mean 74.0±8.8 years, n=25). Baseline characteristics were assessed at admission. Lipid profile was evaluated at admission, 1, 3, 6, 12 and 18 months. The primary outcome was defined 18-month amputation-free survival (AFS). The secondary outcomes were defined 18-month overall survival (OS) and wound-free limb salvage. Mean follow-up period was 18±11 months.

Results

The patients in E group had greater reduction in levels of LDL cholesterol and non-HDL cholesterol than those in Non-E group over time. The reduction in MDA-LDL level was maintained at 1, 3, 6, 12 months, respectively. The 18-month AFS rate in the E-group was significantly higher than those in the Non-E group (log-rank p=0.02). The patients receiving evolocumab had a lower hazard regarding AFS (hazard ratio, 0.12; 95% confidence interval, 0.02–0.94; P=0.043) and a higher proportion of wound-free limb salvage at 12 months (E group [92%] vs Non-E group [57%], P=0.034) and 18 months (92% vs 52%, P=0.03). Otherwise, evolocumab administration was not associated with 18-month OS (log-rank p=0.053).

Conclusions

Evolocumab administration may be associated with the favorable outcome of 18-month AFS in the patients with CLI. Additionally, long-term administration of evolocumab over 12 months may improve wound-free limb salvage.

Effects of evolocumab on limb outcomes

Funding Acknowledgement

Type of funding source: None

Selection of and Retention in Surgical Specialty during Early Career in Japan

The number of surgeons is decreasing in Japan. We investigated the trend and factors influencing surgeons' selection of and retention in surgical specialty. In 2016, we obtained data of biennial surveys conducted by the government, and analyzed the annual data of doctors up to the latest available survey at that time (survey, 1994-2014; medical license acquisition, 1993-2014). The rate of selecting surgery by male and female doctors during early career (first three surveys after acquiring medical license) decreased from 28.1% in 1994 to 21.3% in 2010 (first to nineth survey). Female surgeons increased from 7.8% in 1993 to 12.4% in 2003, but decreased from 12.5% in 2006 to 10.7% in 2010. Total number of surgeons declined throughout the period. In females, the rate of selecting surgery tended to increase at the beginning of the new training system in 2004, but declined slightly thereafter. The retention rate in those who selected surgery at least once by the third survey (1998) after acquiring medical license in 1993 showed a downward trend. The retention rate in females declined continuously to 48.4% in 2002, stabilized thereafter, and then increased from 47.6% in 2006 to 50.8% in 2014. The retention rate after 10 years (1993-2003) was almost stable (72.4%) in males, but increased to 57.5% in females, and the gender difference tended to decrease. Younger doctors tend to value their private life, and may not choose or continue to practice surgery unless working conditions in surgery improve and income is commensurate with their work.

Low‑dose trametinib and Bcl‑xL antagonist have a specific antitumor effect in KRAS‑mutated colorectal cancer cells

KRAS‑mutant colorectal cancer (CRC) is a highly malignant cancer with a poor prognosis, however specific therapies targeting KRAS mutations do not yet exist. Anti‑epidermal growth factor receptor (EGFR) agents, including cetuximab and panitumumab, are effective for the treatment of certain patients with CRC. However, these anti‑EGFR treatments have no effect on KRAS‑mutant CRC. Therefore, new therapeutic strategies targeting KRAS‑mutant CRC are urgently needed. To clarify the direct effect of KRAS gene mutations, the present study transduced mutant forms of the KRAS gene (G12D, G12V and G13D) into CACO‑2 cells. A drug‑screening system (Mix Culture assay) was then applied, revealing that the cells were most sensitive to the MEK inhibitor trametinib among tested drugs, Cetuximab, Panitumumab, Regorafenib, Vemurafenib, BEZ‑235 and Palbociclib. Trametinib suppressed phosphorylated ERK (p‑ERK) expression and inhibited the proliferation of KRAS‑mutant CACO‑2 cells. However, low‑dose treatment with trametinib also increased the expression of the anti‑apoptotic protein Bcl‑xL in a dose‑dependent manner, leading to drug resistance. To overcome the resistance of KRAS‑mutant CRC to apoptosis, the combination of trametinib and the Bcl‑xL antagonist ABT263 was assessed by in vitro and in vivo experiments. Compared with the effects of low‑dose trametinib monotherapy, combination treatment with ABT263 had a synergistic effect on apoptosis in mutant KRAS transductants in vitro. Furthermore, in vivo combination therapy using low‑dose trametinib and ABT263 against a KRAS‑mutant (G12V) xenograft synergistically suppressed growth, with an increase in apoptosis compared with the effects of trametinib monotherapy. These data suggest that a low dose of trametinib (10 nM), rather than the usual dose of 100 nM, in combination with ABT263 can overcome the resistance to apoptosis induced by Bcl‑xL expression, which occurs concurrently with p‑ERK suppression in KRAS‑mutant cells. This strategy may represent a promising new approach for treating KRAS‑mutant CRC.

Amyloid Signature Proteins in Feline Amyloidosis

In human amyloidoses, amyloid signature proteins (ASPs), such as serum amyloid P component (SAP) and apolipoprotein E (ApoE), are deposited in tissues together with amyloid fibrils and are implicated in the pathogenesis of amyloidosis. Few reports describe ASPs in animals. In this study, we examined feline amyloidosis and performed immunohistochemical and proteomic analyses of SAP, ApoE, apolipoprotein A-I (ApoAI) and apolipoprotein A-IV (ApoAIV). Ten cases of systemic amyloidosis, three cases of amyloid-producing odontogenic tumour and three cases of islet amyloidosis were used for immunohistochemistry (IHC) and/or proteomic analyses. IHC showed that ApoE was present in amyloid deposits in all samples. ApoAI and ApoAIV differed in the degree of co-deposition with amyloid depending on the type of amyloid and the affected organ. SAP was negative in all amyloid deposits. Proteomic analysis showed that ApoE was present in all samples, but ApoAI and ApoAIV were detected only in some samples and SAP was not detected in any samples. The observation that ApoE was detected in all types of amyloid suggests the involvement of ApoE in the development of feline amyloidosis. ASPs in feline amyloidosis are significantly different from those in human amyloidosis, suggesting that the involvement of ASPs in the pathological condition differs between animal species.

6121Phrenic nerve injury during pulmonary vein isolation using the second-generation cryoballoon: characteristics and follow-up - The YETI registry

Background

Second-generation cryoballoon (CB2) based pulmonary vein isolation (PVI) has emerged as a safe and effective treatment option for symptomatic atrial fibrillation (AF). Although published complication rates of CB2 based-PVI are relatively low and several safety algorithms have been implemented in the protocols the most frequent complication is right-sided phrenic nerve injury (PNI). The reported incidence of PNI varies from 2–5% of patients. However data on PNI characteristics as well as follow-up is sparse.

Purpose

We aimed to evaluate the incidence, characteristics and outcome of PNI during after CB2 based-PVI in a large patients population.

Methods and results

From July 2012 to November 2018 a total of 13693 patients received CB2 or CB3 (third-generation) based-PVI in 23 EP centers (Germany: 12, China: 1, Turkey: 3, Japan: 3, USA: 1, Austria: 1, Poland: 1, Swizerland: 1). A total of 596 (4.4%) of patients experienced PNI during treatment of the right superior (84%) right inferior (15%) right middle (0.3%) (and left superior (0.3%) pulmonary veins. The mean time to PNI was 127±51 seconds and the mean temperature at the time of PNI was −49±7 °C. The target PV was isolated at time of PNI in 84% of cases. The applications were interrupted using double-stop technique in (71%). In 212/306 (52%) a CMAP was utilized.

At the end of the procedure PNI persistent in 45% of patients. Fluoroscopic or sonographic evaluation of PNI was performed 1–3 days after the procedure and revealed persistent PNI in 35% of patients. Dyspnea before discharge was reported in 18% of patients with persistent PNI. Patients follow up at 1–3, and 6–12 months included fluoroscopy and a visit in an outpatient clinic. After 1–3 months 18% of patients showed persistent PNI including 13% of patients complaining of dyspnea. After 6–12 months of follow-up including fluoroscopic evaluation PNI was persistent in 1.8% of patients while dyspnea was reported by 1.7% patients. Only 0.08% of the overall population of 13693 patients showed permanent and symptomatic PNI.

Conclusion

The incidence of PNI during CB2-based PVI is low. About 55% of PNI recovered until the end of the procedure. Most of PNI recovered within 12 months. Symptomatic permanent PNI is very rare in patients after CB2/CB3-based PVI.

P3389Angioscopic differences in quality and quantity of neointima in patients experiencing an acute coronary syndrome treated with bare metal, first-, second-, and third generation drug-eluting stents

Background

Although drug-eluting stents (DES) have substantially reduced the need for early target lesion revascularization (TLR) compared with bare-metal stents (BMS) by inhibiting neointima hyperplasia, early generation DES have been associated with an increased risk of very late stent failure (VLSF) due to stent thrombosis and TLR after 1 year. Although the incidence of VLSF is reduced with newer generation DES, VLSF remains an unresolved problem and its mechanisms are not fully explored.

Purpose

The purpose of this study was to evaluate quality and quantity of neointima and presence of thrombus by using coronary angioscopy at long-term follow-up in patients who experienced an acute coronary syndrome (ACS) treated with BMS and DES on dual antiplatelet therapy.

Methods

Coronary angioscopy was performed at 6 and 10 months after BMS and DES implantation, respectively, in ACS patients. We assessed neointimal coverage (NC) of the stent struts, yellow color grade (YG) of stented segment and the existence of thrombus. Angioscopic NC was defined as follows: grade 0= fully visible struts; grade 1= visible struts through thin neointima; grade 2= no visible struts. We determined maximum (Max-NC) and minimum coverage (Min-NC) grades and the dominant NC grades. YG was classified into 4 grades (0= white; 1= slight yellow; 2= yellow; 3= intensive yellow). The obtained findings were compared with BMS, first-generation (1st-) DES, second-generation (2nd-) DES and third-generation (3rd-) DES.

Results

A total of 212 patients were enrolled: BMS (n=127), 1st DES (n=26, sirolimus-eluting stent), 2nd-DES (n=38, permanent polymer everolimus-eluting stent), and 3rd-DES (n=21, bioresorbable polymer everolimus-eluting stent). Max-NC and Min-NC grade were significantly lower with 1st- and 2nd-DES than with BMS and 3rd-DES (Figure). The same trend was also observed in the dominant NC grades. There was a lower trend of YG in BMS and 3rd-DES than in 1st or 2nd-DES (Figure). The presence of thrombus was significantly lower in 3rd-DES in comparison with BMS, 1st-, and 2nd-DES (3rd-DES 0%, BMS 20.5%, 1st-DES 24%, 2nd-DES 13.5%, P=0.01).

Figure 1

Conclusion

Patients treated with 3rd-DES have higher NC grade, lower incidence of intrastent thrombus, and lower YG than in 1st and 2nd-DES. These findings may explain the lower incidence of VLSF associated with these newer generation stent platforms.

P5641Impact of lethal arrhythmias on medical castration in patients with prostate cancer

Background

Prostate cancer is the most common non-cutaneous malignancy in men and has been steadily rising in an aging society. Medical castration had been widely applied as a treatment for prostate cancer. Sex steroid hormones regulate cardiac ion channels. However, the proarrhythmic properties of medical castration have not been reported.

Methods

This prospective observational study consisted of 149 patients (75±6 years) who underwent hormonal therapy using gonadotropin-releasing hormone with or without anti-androgen for prostate cancer. The changes of electrocardiogram (ECG) findings during the therapy and the associations of ECG findings with lethal arrhythmias were studied.

Results

QT (394±32 to 406±39 ms, p<0.001) and QTc intervals (416±27 to 439±31 ms, p<0.001) significantly prolonged during the therapy as compared to baseline. Heart rate significantly increased during the therapy as compared to baseline (68±11 to 71±14 / min, p=0.006). PQ interval and QRS duration were similar before and during the therapy. During the hormonal therapy, 2 patients (1.3%) presented with torsades de pointes and ventricular fibrillation. The first patient was 71 year-old and the second patient was 70 year-old. The period of the therapy was 6 and 45 months, respectively. Both patients had no structural heart disease. The magnitude of QTc interval change during the therapy as compared to baseline (Δ QTc interval) was significantly greater in patients with VF than those without (p<0.001), however the magnitude of Δ heart rate, Δ PQ interval, and Δ QRS duration were similar between the 2 groups.

Conclusions

Medical castration significantly prolonged QT/QTc interval and could be a trigger of lethal arrhythmias in patients with prostate cancer.

P6339Sequential organ failure assessment score on admission predicts long-time mortality of the patients with acute heart failure

Background

Despite the remarkable advances in the treatment options of acute heart failure (HF), prognosis assessment remains an ongoing challenge. Previous studies revealed only a moderate accuracy of models predicting mortality. Sequential Organ Failure Assessment (SOFA) Score are widely used in the intensive care unit (ICU) to predict outcome and predicted higher long-time mortality in unselected patients in cardiac ICU. In addition, the American Heart Association Get With the Guidelines–Heart Failure (GWTG-HF) risk score allows for risk stratification of 30-day outcome for patients hospitalized with HF. The purpose of this study was to evaluate whether SOFA score on admission is useful for long-time mortality prediction in acute HF patients and also to assess the discriminative performance as compared with GWTG-HF risk score.

Methods

This was a single-centre, retrospective cohort study. Between January 2007 and December 2016, we screened eligible 661 consecutive patients with acute HF administered at our hospital. SOFA score on admission of 294 patients was able to calculate retrospectively. We enrolled 269 patients who could complete follow up evaluation for more than 1 year. Endpoint was all-cause mortality after admission. Additive information of SOFA score was evaluated by area under the curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI) and decision curve analysis (DCA).

Results

The 269 patients were included in this study (78.5±10.9 years; 136 men; left ventricular ejection fraction [EF], 49.8±16.6%) during a mean follow-up of 32.1±22.3 months. Patients with all-cause death had higher SOFA score (4.2±2.3 versus 2.8±1.8, p<0.001; AUC, 0.689) and GWTG-HF risk score (44.0±7.6 versus 38.1±7.9, P<0.001, AUC, 0.692).

Kaplan-Meier survival analysis demonstrated higher SOFA scores (P<0.001) and GWTG-HF risk scores (P<0.001) appears to be related to increase probabilities of all cause death. A multivariate Cox proportional hazard model were made with adjustment for SOFA score, GWTG-HF risk score, age, gender and ejection fraction. As a result, SOFA score (hazard ratio [HR] 1.227; 95% confidence interval [CI], 1.130 to 1.326; P<0.001), GWTG-HF (HR, 1.054; 95% CI, 1.029 to 1.078; P<0.001) and age (HR, 1.069; 95% CI 1.048 to 1.092; P<0.001) were independent predictors of all cause death and HR of SOFA score was the highest in these parameters. Incorporating SOFA score into GWTG-HF score yielded a significant NRI (0.528 (95% CI 0.291 to 0.765) and IDI (0.046 (95% CI 0.020 to 0.072). In DCA, compared with the reference model, the net benefit for SOFA score model was greater across the range of threshold probabilities.

Conclusions

The SOFA score, simple and validated mortality risk score can predict long-term all-cause mortality in patients with acute HF. Discriminative performance metrics such as NRI, IDI and DCA were improved on incorporation of the SOFA score for prediction of mortality.

Pharmacological inhibition of mTORC1 but not mTORC2 protects against human disc cellular apoptosis, senescence, and extracellular matrix catabolism through Akt and autophagy induction

OBJECTIVE

The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that integrates nutrients to execute cell growth. We hypothesized that mTOR is influential in the intervertebral disc-largest avascular, low-nutrient organ. Our objective was to identify the optimal mTOR inhibitor for treating human degenerative disc disease.

DESIGN

mTOR complex 1 (mTORC1) regulates p70/ribosomal S6 kinase (p70/S6K), negatively regulates autophagy, and is controlled by Akt. Akt is controlled by phosphatidylinositol 3-kinase (PI3K) and mTOR complex 2 (mTORC2). mTORC1 inhibitors-rapamycin, temsirolimus, everolimus, and curcumin, mTORC1&mTORC2 inhibitor-INK-128, PI3K&mTOR inhibitor-NVP-BEZ235, and Akt inhibitor-MK-2206-were applied to human disc nucleus pulposus (NP) cells. mTOR signaling, autophagy, apoptosis, senescence, and matrix metabolism were evaluated.

RESULTS

mTORC1 inhibitors decreased p70/S6K but increased Akt phosphorylation, promoted autophagy with light chain 3 (LC3)-II increases and p62/sequestosome 1 (p62/SQSTM1) decreases, and suppressed pro-inflammatory interleukin-1 beta (IL-1β)-induced apoptotic terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positivity (versus rapamycin, 95% confidence interval (CI) -0.431 to -0.194; temsirolimus, 95% CI -0.529 to -0.292; everolimus, 95% CI -0.477 to -0.241; curcumin, 95% CI -0.248 to -0.011) and poly (ADP-ribose) polymerase (PARP) and caspase-9 cleavage, senescent senescence-associated beta-galactosidase (SA-β-gal) positivity (versus rapamycin, 95% CI -0.437 to -0.230; temsirolimus, 95% CI -0.534 to -0.327; everolimus, 95% CI -0.485 to -0.278; curcumin, 95% CI -0.210 to -0.003) and p16/INK4A expression, and catabolic matrix metalloproteinase (MMP) release and activation. Meanwhile, dual mTOR inhibitors decreased p70/S6K and Akt phosphorylation without enhanced autophagy and suppressed apoptosis, senescence, and matrix catabolism. MK-2206 counteracted protective effects of temsirolimus. Additional disc-tissue analysis found relevance of mTOR signaling to degeneration grades.

CONCLUSION

mTORC1 inhibitors-notably temsirolimus with an improved water solubility-but not dual mTOR inhibitors protect against inflammation-induced apoptosis, senescence, and matrix catabolism in human disc cells, which depends on Akt and autophagy induction.

Efficacy and safety of concurrent anti-Cancer and anti-tuberculosis chemotherapy in Cancer patients with active Mycobacterium tuberculosis: a retrospective study

Background

In our previous study, colorectal cancer (CRC) patients with active Mycobacterium tuberculosis (MTB) tolerated concurrent anti-cancer chemotherapy (anti-CCT) and anti-MTB chemotherapy. In this study, we retrospectively confirmed the efficacy and safety of concurrent chemotherapy in a greater number of patients with different types of malignancies.

Methods

We enrolled 30 patients who were treated concurrently with anti-CCT and anti-MTB regimens between January 2006 and February 2016. Cancer and MTB treatments were administered according to the approved guidelines.

Results

Patient demographics included: men/woman: 24/6; median age: 66.5 years; Eastern Cooperative Oncology Group performance status 0–1/2/3–4: 24/4/2; Stage IIB–IIIC/IV/recurrence: 6/22/2; lung cancer (LC)/CRC/other: 15/10/5; and MTB diagnosis (before or during anti-CCT): 20/10 (LC: 8/7; CRC: 8/2; other: 4/1). For anti-CCT, 23 patients received two cytotoxic agents with or without targeted agents and 7 patients received a single cytotoxic or targeted agent. The overall response rate was 36.7%. Regarding anti-MTB chemotherapy, 22 patients received a daily drug combination containing isoniazid, rifampicin, and ethambutol, plus pyrazinamide in 15 of the 22 patients, followed by daily isoniazid and rifampicin; the remaining 8 patients received other combinations. Hematological adverse events of Grade ≥ 3 were observed in 19 (67.9%) of 28 patients; laboratory data were lost for the remaining 2. Grade 3 lymphopenia and higher were significantly more frequent in LC compared to other malignancies (P < 0.005). Non-hematological adverse events of Grade ≥ 3 were observed in 5 (16.7%) of 30 patients. One CRC patient experienced Grade 3 hemoptysis and another 2 experienced Grade 3 anaphylaxis. One patient with cholangiocellular carcinoma and gastric cancer experienced Grade 3 pseudomembranous colitis as a result of a Clostridium difficile infection. One patient (3.3%) died of pemetrexed-induced pneumonitis. The success of the anti-MTB chemotherapy was 70.0%. There were no MTB-related treatment failures. The median overall survival (months, 95.0% confidence interval) was 10.5 (8.7–36.7), 8.7 (4.7–10.0), 36.7 (minimum 2.2), and 14.4 (minimum 9.6) for all patients combined, LC, CRC, and Other malignancies, respectively. LC patients experienced delayed MTB diagnosis and shorter overall survival.

Conclusions

Concurrent chemotherapy is effective and safe for treating cancer patients with active MTB.