Simple smoke ventilation method for uniportal video-assisted thoracoscopic surgery

Fogging of the thoracoscopic lens affects a surgeon’s ability to maintain a clear operating field. In uniportal video-assisted thoracoscopic surgery, the thoracoscopic lens tends to fog when the surgeon does not hold a suction instrument. Thus, a suction instrument needs to be held by the surgeon’s nondominant hand to remove surgical smoke, mist, and moisture. Here, we describe a simple, easy and cost-effective surgical smoke ventilation technique for uniportal video-assisted thoracoscopic surgery using a suction catheter to solve the problem. We present this technique and comment on its advantages, including decreased cost and improved surgical visualization.     

Phase IIb study of pembrolizumab combined with S‐1 + oxaliplatin or S‐1 + cisplatin as first‐line chemotherapy for gastric cancer

The KEYNOTE‐659 study evaluated the efficacy and safety of first‐line pembrolizumab plus S‐1 and oxaliplatin (SOX) (cohort 1) or S‐1 and cisplatin (SP) (cohort 2) for advanced gastric/gastroesophageal junction (G/GEJ) cancer in Japan. Herein, we update the results of cohort 1 and describe the results of cohort 2. This open‐label phase IIb study enrolled patients with advanced programmed death‐ligand 1 (PD‐L1)‐positive (combined positive score ≥ 1) human epidermal growth factor receptor 2 (HER2)‐negative G/GEJ adenocarcinoma. The primary end‐point was the objective response rate (ORR). Other end‐points were duration of response (DOR), disease control rate (DCR), progression‐free survival (PFS), overall survival (OS), and safety. One hundred patients were enrolled. In cohorts 1 and 2, median follow‐up time was 16.9 and 17.1 months; ORR (central review), 72.2% and 80.4%; DOR, 10.6 and 9.5 months; DCR (central review), 96.3% and 97.8%; median PFS (central review), 9.4 and 8.3 months; and median OS, 16.9 and 17.1 months, respectively. Treatment‐related adverse events (TRAEs) occurred in all patients, including peripheral sensory neuropathy (94.4%, cohort 1), decreased neutrophil count (82.6%, cohort 2), nausea (59.3% and 60.9% in cohorts 1 and 2), and decreased appetite (61.1% and 60.9% in cohorts 1 and 2). Grade 3 or higher TRAEs were reported by 59.3% (cohort 1) and 78.3% (cohort 2), including decreased platelet count (14.8%, cohort 1) and decreased neutrophil count (52.2%, cohort 2). Pembrolizumab in combination with SOX or SP showed favorable efficacy and safety in patients with PD‐L1‐positive, HER2‐negative G/GEJ adenocarcinoma.     

Japanese trial for classification of gestational trophoblastic disease

OBJECTIVE: To evaluate the clinical usefulness of the Japanese Diagnostic Score to differentiate choriocarcinoma clinically without histologic findings from persistent gestational trophoblastic disease (GTD). STUDY DESIGN: We reviewed the clinical records and histologic reports on all 809 patients with persistent GTD treated with surgery and chemotherapy in Japan. There were 347 cases of choriocarcinoma and 462 cases of invasive mole with histologic confirmation. We retrospectively applied the Japanese Diagnostic Score to all patients for detection of choriocarcinoma in persistent trophoblastic disease. RESULTS: The sensitivity of the score for choriocarcinoma was 92.2%. The specificity was 93.5%. This retrospective study showed that the accuracy of this scoring system to differentiate true malignant choriocarcinoma clinically from both low risk and high risk gestational trophoblastic neoplasia without histologic findings was 92.9%. CONCLUSION: Our trial to differentiate choriocarcinoma clinically from persistent GTD without histologic findings using a unique scoring system was successful. Proper management in the early stages strongly influences the outcome of these diseases. This scoring system should be very useful in comparing the incidence and survival rate of choriocarcinoma between nations.     

Inadequate tolerance induction may induce pre-eclampsia

The fetus is semi-allograft to the maternal host; therefore, a system of tolerance must be present during pregnancy. Epidemiological findings support a relationship between pre-eclampsia and the failure of tolerance induction. For induction of major histocompatibility complex (MHC) class I-specific tolerance, long-term exposure to seminal fluid, which contains paternal soluble MHC class I antigens, may induce paternal MHC class I-specific tolerance. Furthermore, soluble HLA-G1, which induces the deletion of CD8(+) T-cells, and the combination of maternal killer-immunoglobulin-like receptors (KIR) on NK cells and fetal HLA-C, which affects the balance between inhibition and activation signals of NK cells, regulatory CD8(+) T cells, and regulatory NK cells, may play very important roles in the induction of MHC class I-specific tolerance. On the other hand, exposure to sperm, which express paternal HLA-DR, and trophoblastic debris, which contain intracellular fetal HLA-DR, may induce paternal MHC class II-specific tolerance. In this process, CD4(+)CD25(+) regulatory T (Treg)-cells play central roles. In this review, we discuss the relationship between the risk of pre-eclampsia and tolerance induction.     

HLA-A Alleles and the Risk of Cervical Squamous Cell Carcinoma in Japanese Women

Background

We conducted a case-control study to examine the relationship between human leukocyte antigen-A (HLA-A) allele polymorphism and the pathogenesis of cervical neoplasia among Japanese women.

Methods

A total of 119 patients with invasive cervical squamous cell carcinoma were compared to 119 age- and menopausal status-matched non-cancer controls. Blood samples were taken from all cases and controls and lifestyle information was collected by means of a self-administered questionnaire. The estimated impact of HLA-A alleles on cervical cancer risk was evaluated by unconditional logistic regression models.

Results

The frequency of HLA-A*0206 among cases was significantly lower than among controls (P = 0.006). There was an inverse association between A*0206 and cervical cancer risk (odds ratio [OR] = 0.31, 95% confidence interval [95% CI] = 0.15 to 0.65, P = 0.002), and a positive association for HLA-A*2402 (OR = 1.76, 95% CI = 1.00 to 3.09, P = 0.048). After correction for multiple comparisons, A*0206 was significantly associated with reduced cervical cancer risk (corrected P = 0.036). Furthermore, the inverse association between A*0206 and cervical cancer risk was independent of smoking status (never smoker: OR = 0.37, 95% CI = 0.15 to 0.90; ever smoker: OR = 0.23, 95% CI = 0.06 to 0.89).

Conclusions

There was an inverse association between HLA-A*0206 and cervical cancer risk among Japanese women, which suggests that HLA-A polymorphism influences cervical cancer risk. Further investigation in other populations is thus warranted.Key words: cervical cancer, human leukocyte antigen, case-control study     

Development of the Japanese version of the Pediatric Quality of Life Inventory™ Brain Tumor Module

Background

The Pediatric Quality of Life Inventory? (PedsQL?) is a widely-used modular instrument for measuring health-related quality of life in children aged 2 to 18 years. The PedsQL? Brain Tumor Module is comprised of six scales: Cognitive Problems, Pain and Hurt, Movement and Balance, Procedural Anxiety, Nausea, and Worry. In the present study, we developed the Japanese version of the PedsQL? Brain Tumor Module and investigated its feasibility, reliability, and validity among Japanese children and their parents.

Methods

Translation equivalence and content validity were verified using the standard back-translation method and cognitive debriefing tests. Participants were recruited from 6 hospitals in Japan and the Children's Cancer Association of Japan, and questionnaires were completed by 137 children with brain tumors and 166 parents. Feasibility of the questionnaire was determined based on the amount of time required to complete the form and the percentage of missing values. Internal consistency was assessed using Cronbach's coefficient alpha. Test-retest reliability was assessed by retesting 22 children and 27 parents. Factorial validity was verified by exploratory factor analyses. Known-groups validity was described with regard to whole brain irradiation, developmental impairment, infratentorial tumors, paresis, and concurrent chemotherapy. Convergent and discriminant validity were determined using Generic Core Scales and State-Trait Anxiety Inventory for children.

Results

Internal consistency was relatively high for all scales (Cronbach's coefficient alpha > 0.70) except the Pain and Hurt scale for the child-report, and sufficient test-retest reliability was demonstrated for all scales (intraclass correlation coefficient = 0.45-0.95). Factorial validity was supported through exploratory factor analysis (factor-item correlation = 0.33-0.96 for children, 0.55-1.00 for parents). Evaluation of known-groups validity confirmed that the Cognitive Problems scale was sensitive for developmental impairment, the Movement and Balance scale for infratentorial tumors or paresis, and the Nausea scale for a patient currently undergoing chemotherapy. Convergent and discriminant validity with the PedsQL? Generic Core Scales and State-Trait Anxiety Inventory for children were acceptable.

Conclusions

The Japanese version of the PedsQL? Brain Tumor Module is suitable for assessing health-related quality of life in children with brain tumors in clinical trials and research studies.     

A two-component protein condensate of the EGFR cytoplasmic tail and Grb2 regulates Ras activation by SOS at the membrane

We reconstitute a phosphotyrosine-mediated protein condensation phase transition of the ∼200 residue cytoplasmic tail of the epidermal growth factor receptor (EGFR) and the adaptor protein, Grb2, on a membrane surface. The phase transition depends on phosphorylation of the EGFR tail, which recruits Grb2, and crosslinking through a Grb2-Grb2 binding interface. The Grb2 Y160 residue plays a structurally critical role in the Grb2-Grb2 interaction, and phosphorylation or mutation of Y160 prevents EGFR:Grb2 condensation. By extending the reconstitution experiment to include the guanine nucleotide exchange factor, SOS, and its substrate Ras, we further find that the condensation state of the EGFR tail controls the ability of SOS, recruited via Grb2, to activate Ras. These results identify an EGFR:Grb2 protein condensation phase transition as a regulator of signal propagation from EGFR to the MAPK pathway.

Recently, a class of phenomena known as protein condensation phase transitions has begun to emerge in biology. Originally identified in the context of nuclear organization (1) and gene expression (2), a distinct two-dimensional protein condensation on the cell membrane has now been discovered in the T cell receptor (TCR) signaling system involving the scaffold protein LAT (3–5). TCR activation results in phosphorylation of LAT on at least four distinct tyrosine sites, which subsequently recruit the adaptor protein Grb2 and the signaling molecule PLCγ via selective binding interactions with their SH2 domains. Additional scaffold and signaling molecules, including SOS, GADS, and SLP76, are recruited to Grb2 and PLCγ through further specific protein–protein interactions (6, 7). Multivalency among some of these binding interactions can crosslink LAT molecules in a two-dimensional bond percolation network on the membrane surface. The resulting LAT protein condensate resembles the nephrin:NCK:N-WASP condensate (8) in that both form on the membrane surface under control of tyrosine phosphorylation and exert at least one aspect of functional control over signaling output via a distinct type of kinetic regulatory mechanism (9–11). The basic molecular features controlling the LAT and nephrin protein condensates are common among biological signaling machinery, and other similar condensates continue to be discovered (12, 13). The LAT condensation shares downstream signaling molecules with the EGF-receptor (EGFR) signaling system, raising the question if EGFR may participate in a signaling-mediated protein condensation itself.EGFR signals to the mitogen-activated protein kinase (MAPK) pathway and controls key cellular functions, including growth and proliferation (14–16). EGFR is a paradigmatic model system in studies of signal transduction, and immense, collective scientific effort has revealed the inner workings of its signaling mechanism down to the atomic level (17). EGFR is autoinhibited in its monomeric form. Ligand-driven activation is achieved through formation of an asymmetric receptor dimer in which one kinase activates the other to phosphorylate the nine tyrosine sites in the C-terminal tails (17, 18). There is an obvious conceptual connection between EGFR and the LAT signaling system in T cells. The ∼200-residue–long cytoplasmic tail of EGFR resembles LAT in that both are intrinsically disordered and contain multiple sites of tyrosine phosphorylation that recruit adaptor proteins, including Grb2, upon receptor activation (19). Phosphorylation at tyrosine residues Y1068, Y1086, Y1148, and Y1173 in the EGFR tail creates sites to which Grb2 can bind via its SH2 domain. EGFR-associated Grb2 subsequently recruits SOS, through binding of its SH3 domains to the proline-rich domain of SOS. Once at the membrane, SOS undergoes a multistep autoinhibition-release process and begins to catalyze nucleotide exchange of RasGDP to RasGTP, activating Ras and the MAPK pathway (20).While these most basic elements of the EGFR activation mechanism are widely accepted, larger-scale features of the signaling complex remain enigmatic. A number of studies have reported higher-ordered multimers of EGFR during activation, including early observations by Förster Resonance Energy Transfer and fluorescence lifetime studies (21–23), as have more recent studies using single molecule (24, 25) and computational methods (26). Structural analyses and point mutation studies on EGFR have identified a binding interface enabling EGFR asymmetric dimers to associate (27), but the role of these higher-order assemblies remains unclear. At the same time, many functional properties of the signaling system remain unexplained as well. For example, EGFR is a frequently altered oncogene in human cancers, and drugs (including tyrosine kinase inhibitors) targeting EGFR signaling have produced impressive initial patient responses (28). All too often, however, these drugs fail to offer sustained patient benefits, in large part because of poorly understood resistance mechanisms (29). Physical aspects of the cellular microenvironment have been implicated as possible contributors to resistance development (30), and there is a growing realization that EGFR possesses kinase-independent (e.g., signaling independent) prosurvival functions in cancer cells (31). These points fuel speculation that additional layers of regulation over the EGFR signaling mechanism exist, including at the level of the receptor signaling complex itself.Here we report that EGFR undergoes a protein condensation-phase transition upon activation. We reconstituted the cytoplasmic tails of EGFR on supported bilayers and characterized the system behavior upon interaction with Grb2 and SOS, using total internal reflection fluorescence (TIRF) imaging. This experimental platform has been highly effective for revealing both phase-transition characteristics and functional signaling aspects of LAT protein condensates (4, 5, 10, 32–34). Published reports on the LAT system to date have emphasized SOS (or the SOS proline-rich [PR] domain) as a critical crosslinking element. Titrating the SOS PR domain into an initially homogeneous mixture of phosphorylated LAT and Grb2 revealed a sharp transition to the condensed phase, which we have also observed with the EGFR:Grb2:SOS system. Under slightly different conditions, however, we report observations of an EGFR:Grb2 condensation-phase transition without any SOS or other crosslinking molecule. We show that crosslinking is achieved through a Grb2–Grb2 binding interface. Phosphorylation on Grb2 at Y160 as well as a Y160E mutation [both reported to disrupt Grb2–Grb2 binding (35, 36)] were observed to prevent formation of EGFR condensates. We note that the evidence of Grb2–Grb2 binding we observed occurred in the context of EGFR-associated Grb2, which is localized to the membrane surface; free Grb2 dimers are not necessary.The consequence of EGFR condensation on downstream signaling is characterized by mapping the catalytic efficiency of SOS to activate Ras as a function of the EGFR condensation state. SOS is the primary Ras guanine nucleotide exchange factor (GEF) responsible for activating Ras in the EGFR-to-MAPK signaling pathway (37–40). At the membrane, SOS undergoes a multistep process of autoinhibition release before beginning to activate Ras. Once fully activated, SOS is highly processive, and a single SOS molecule can activate hundreds of Ras molecules before disengaging from the membrane (41–43). Autoinhibition release in SOS is a slow process, which necessitates that SOS be retained at the membrane for an extended time in order for Ras activation to begin (5, 10). This delay between initial recruitment of SOS and subsequent initiation of its Ras GEF activity provides a kinetic proofreading mechanism that essentially requires SOS to achieve multivalent engagement with the membrane (e.g., through multiple Grb2 or other interactions) in order for it to activate any Ras molecules.Experimental results described here reveal that Ras activation by SOS is strongly enhanced by EGFR condensation. Calibrated measurements of both SOS recruitment and Ras activation confirmed enhanced SOS catalytic activity on a per-molecule basis, in addition to enhanced recruitment to the condensates. These results suggest that a Grb2-mediated EGFR protein condensation-phase transition is a functional element controlling signal propagation from EGFR downstream to the MAPK signaling pathway.     

Effect of providing risk information on undergoing cervical cancer screening: a randomized controlled trial

Background

In Japan, the cervical cancer screening rate is extremely low. Towards improving the cervical cancer screening rate, encouraging eligible people to make an informed choice, which is a decision-making process that relies on beliefs informed by adequate information about the possible benefits and risks of screening, has attracted increased attention in the public health domain. However, there is concern that providing information on possible risks of screening might prevent deter from participating.

Methods

In total, 1,912 women aged 20–39 years who had not participated in screening in the fiscal year were selected from a Japanese urban community setting. Participants were randomly divided into 3 groups. Group A received a printed reminder with information about the possible benefits of screening, group B received a printed reminder with information about possible benefits and risks, and group C received a printed reminder with simple information only (control group).

Results

Out of 1,912 participants, 169 (8.8%) participated in cervical cancer screening. In the intervention groups, 137 (10.9%) participated in cervical cancer screening, compared to only 32 (4.9%) of the control group (p < 0.001). In addition, logistic regression analysis revealed that there was no significant difference in screening rate between group A and group B (p = 0.372).

Conclusions

Providing information on the possible risks of screening may not prevent people from taking part in cervical cancer screening among a Japanese non-adherent population.     

Phospholamban p.Arg14del Cardiomyopathy: A Japanese Case Series

Phospholamban p.Arg14del is reported to cause hereditary cardiomyopathy with malignant ventricular tachycardia (VT) and advanced heart failure. However, the clinical courses of Japanese cardiomyopathy patients with phospholamban p.Arg14del remain uncharacterized. We identified five patients with this variant. All patients were diagnosed with dilated cardiomyopathy (DCM), developed end-stage heart failure and experienced VT requiring implantable cardioverter defibrillator discharge. Four patients survived after implantation of a left ventricular assist device (LVAD), while one patient who refused LVAD implantation died of heart failure. Based on the severe course of the disease, we propose genetic screening for phospholamban p.Arg14del in DCM patients.