CHEMORESISTANCE RELATED TO HYPOXIA ADAPTATION IN MESOTHELIOMA CELLS FROM TUMOR SPHEROIDS.

BACKGROUND: Hypoxia has been noted as a key factor for induction and maintenance of cancer stemness thereby leading to therapy resistance. Three-dimensional (3D) spheroid models demonstrate a heterogeneity of hypoxic regions replicating the in vivo situation within tumors. Utilizing an established 3D spheroid model, we investigated whether extrinsic hypoxia reinforced chemoresistance in malignant pleural mesothelioma (MPM) spheroids. MATERIALS AND METHODS: Tumor spheres were generated from Meso-1 (a typical human MPM cell line) cells having high spheroid-forming ability. To induce hypoxia condition, we utilized a hypoxia chamber with regulation of O2 and CO2 levels. Cell viability was estimated by a WST-8 assay. Real-time polymerase chain reaction and Western blot were performed to evaluate the expression at mRNA and protein levels. RESULTS: Compared with cells cultured in the two-dimensional monolayer model, tumor sphere cells showed elevated mRNA levels of cancer stemness markers (CD26, CD44 and ABCG2) and protein levels of the stemness and hypoxia adaptation markers (ABCG2, ALDH1A1 and HIFs). Correlating with this, 3D spheroid cells were more resistant to permetrexed and topotecan than the two-dimensional cells, indicative of their potential for hypoxic adaptation. Furthermore, significantly stronger resistance to both chemotherapeutic agents was observed in spheroid cells upon hypoxic challenge compared to spheroid cells under normoxia. CONCLUSION: From the present data, it is concluded that hypoxia adaptation of MPM cells from tumor spheres could enhance their chemoresistance.

Juzentaihoto extract suppresses adipocyte hypertrophy and improves hyperglycemia in KKAy mice.

Juzentaihoto is a herbal medicine with reported anti-inflammatory effects, and it is predicted to improve inflammation and insulin sensitivity within obesity. In the present study, juzentaihoto hot water extract (JTT) was administered to obese type 2 diabetic model mice (KKAy) for 56 days. In addition, the effects of JTT on the adipose tissue, glucose metabolism, and blood lipids were evaluated for examining its impact on insulin sensitivity and obesity. As a result of JTT administration, KKAy mice exhibited suppressed adipocyte hypertrophy, decreased the mRNA levels of tumor necrosis factor α, and increased the mRNA levels of adiponectin in epididymal fat tissue. In addition, fasting blood glucose levels, blood triglyceride, and total cholesterol decreased. In summary, these data indicated that JTT administration suppressed the production of inflammatory cytokines and increased adiponectin levels in the adipose tissue. Therefore, with improved insulin sensitivity, blood glucose, and lipid decreased.

Effect of high ligation on survival of patients undergoing surgery for primary colorectal cancer and synchronous liver metastases.

BACKGROUND: Although R0 surgery is recommended for stage IV colorectal cancer, the degree of required lymphadenectomy has not been established. The aim of this study was to investigate the prognostic impact of high ligation (HL) of the feeding artery and the number of retrieved lymph nodes after R0 surgery for colorectal cancer and synchronous colorectal cancer liver metastasis (CRLM). METHODS: This was a multi-institutional retrospective analysis of patients with colorectal cancer and synchronous CRLM who had R0 surgery between January 1997 and December 2007. Clinical and pathological features were compared in patients who underwent HL and those who had a low ligation (LL). Kaplan-Meier analysis was performed to estimate the effect of HL on overall survival (OS). The impact of several risk factors on survival was analysed using the Cox proportional hazards model. RESULTS: Of 549 patients, 409 (74·5 per cent) had HL. Median follow-up was 51·4 months. HL significantly improved the 5-year OS rate (58·2 per cent versus 49·3 per cent for LL; P = 0·017). Multivariable analysis revealed HL to be a significant prognostic factor compared with LL (5-year mortality: hazard ratio (HR) 0·68, 95 per cent c.i. 0·51 to 0·90; P = 0·007). In subgroup analysis, the positive effect of HL on OS was greatest in patients with lymph node metastasis. CONCLUSION: HL of the feeding artery was associated with improved OS in patients with colorectal cancer and synchronous CRLM after R0 surgery.

ANTECEDENTES: Aunque se recomienda una cirugía R0 para el cáncer colorrectal (colorectal cancer, CRC) en estadio IV, no se ha establecido el grado de linfadenectomía requerida. El objetivo de este estudio fue investigar el impacto pronóstico de la ligadura alta (high ligation, HL) de la arteria que irriga el tumor y el número de ganglios linfáticos (lymph nodes, LN) identificados después de cirugía R0 en pacientes con cáncer colorrectal y metástasis hepáticas sincrónicas (colorectal cancer liver metastasis, CRLM). MÉTODOS: En este estudio se realizó un análisis retrospectivo multicéntrico de pacientes con CRC y CRLM sincrónicas en los que se realizó una cirugía R0 desde enero de 1997 hasta diciembre de 2007. Se compararon las características clínicas y patológicas entre los pacientes a los que, durante la cirugía R0, se practicó una HL frente a los que no se practicó esta técnica. El análisis de Kaplan-Meier se realizó para estimar el efecto de la HL en la supervivencia global (overall survival, OS). El impacto de varios factores de riesgo sobre la supervivencia se analizó utilizando el modelo de Cox de riesgo proporcional. RESULTADOS: Sobre un total de 549 pacientes, se realizó una HL en 409 (74,5%), y el período de seguimiento medio en esta cohorte fue de 51,4 meses. La HL mejoró significativamente la tasa de OS a los 5 años (HL 37,7% versus no HL 27,1%, P = 0,02). El análisis multivariable mostró que la HL era un factor pronóstico significativo en comparación con la no realización de una HL (cociente de riesgos instantáneos, hazard ratio, HR de muerte a 5 años = 0,68 (i.c. del 95% 0,51-0,90), P < 0,01)). En el análisis de subgrupos, el efecto positivo de la HL sobre la OS fue mayor en pacientes con metástasis ganglionares. CONCLUSIÓN: La ligadura alta de la arteria que irriga el tumor se asoció con una mejor OS en pacientes con CRC y CRLM sincrónicas después de una cirugía R0.

Complex evolution of the GSTM gene family involves sharing of GSTM1 deletion polymorphism in humans and chimpanzees.

BACKGROUND: The common deletion of the glutathione S-transferase Mu 1 (GSTM1) gene in humans has been shown to be involved in xenobiotic metabolism and associated with bladder cancer. However, the evolution of this deletion has not been investigated. RESULTS: In this study, we conducted comparative analyses of primate genomes. We demonstrated that the GSTM gene family has evolved through multiple structural variations, involving gene duplications, losses, large inversions and gene conversions. We further showed experimentally that the GSTM1 was polymorphically deleted in both humans and also in chimpanzees, through independent deletion events. To generalize our results, we searched for genic deletions that are polymorphic in both humans and chimpanzees. Consequently, we found only two such deletions among the thousands that we have searched, one of them being the GSTM1 deletion and the other surprisingly being another metabolizing gene, the UGT2B17. CONCLUSIONS: Overall, our results support the emerging notion that metabolizing gene families, such as the GSTM, NAT, UGT and CYP, have been evolving rapidly through gene duplication and deletion events in primates, leading to complex structural variation within and among species with unknown evolutionary consequences.

Non-traumatic hemorrhage is controlled with REBOA in acute phase then mortality increases gradually by non-hemorrhagic causes: DIRECT-IABO registry in Japan.

PURPOSE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is now a feasible and less invasive resuscitation procedure. This study aimed to compare the clinical course of trauma and non-trauma patients undergoing REBOA. METHODS: Patient demographics, etiology, bleeding sites, hemodynamic response, length of critical care, and cause of death were recorded. Characteristics and outcomes were compared between non-trauma and trauma patients. Kaplan-Meier survival analysis was then conducted. RESULTS: Between August 2011 and December 2015, 142 (36 non-trauma; 106 trauma) cases were analyzed. Non-traumatic etiologies included gastrointestinal bleeding, obstetrics and gynecology-derived events, visceral aneurysm, abdominal aortic aneurysm, and post-abdominal surgery. The abdomen was a common bleeding site (69%), followed by the pelvis or extra-pelvic retroperitoneum. None of the non-trauma patients had multiple bleeding sites, whereas 45% of trauma patients did (P < 0.001). No non-trauma patients required resuscitative thoracotomy compared with 28% of the trauma patients (P < 0.001). Non-trauma patients presented a lower 24-h mortality than trauma patients (19 vs. 51%, P = 0.001). The non-trauma cases demonstrated a gradual but prolonged increased mortality, whereas survival in trauma cases rapidly declined (P = 0.009) with similar hospital mortality (68 vs. 64%). Non-trauma patients who survived for 24 h had 0 ventilator-free days and 0 ICU-free days vs. a median of 19 and 12, respectively, for trauma patients (P = 0.33 and 0.39, respectively). Non-hemorrhagic death was more common in non-trauma vs. trauma patients (83 vs. 33%, P < 0.001). CONCLUSIONS: Non-traumatic hemorrhagic shock often resulted from a single bleeding site, and resulted in better 24-h survival than traumatic hemorrhage among Japanese patients who underwent REBOA. However, hospital mortality increased steadily in non-trauma patients affected by non-hemorrhagic causes after a longer period of critical care.

The use of aortic balloon occlusion in traumatic shock: first report from the ABO trauma registry.

PURPOSE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique for temporary stabilization of patients with non-compressible torso hemorrhage. This technique has been increasingly used worldwide during the past decade. Despite the good outcomes of translational studies, clinical studies are divided. The aim of this multicenter-international study was to capture REBOA-specific data and outcomes. METHODS: REBOA practicing centers were invited to join this online register, which was established in September 2014. REBOA cases were reported, both retrospective and prospective. Demographics, injury patterns, hemodynamic variables, REBOA-specific data, complications and 30-days mortality were reported. RESULTS: Ninety-six cases from 6 different countries were reported between 2011 and 2016. Mean age was 52 ± 22 years and 88% of the cases were blunt trauma with a median injury severity score (ISS) of 41 (IQR 29-50). In the majority of the cases, Zone I REBOA was used. Median systolic blood pressure before balloon inflation was 60 mmHg (IQR 40-80), which increased to 100 mmHg (IQR 80-128) after inflation. Continuous occlusion was applied in 52% of the patients, and 48% received non-continuous occlusion. Occlusion time longer than 60 min was reported as 38 and 14% in the non-continuous and continuous groups, respectively. Complications, such as extremity compartment syndrome (n = 3), were only noted in the continuous occlusion group. The 30-day mortality for non-continuous REBOA was 48%, and 64% for continuous occlusion. CONCLUSIONS: This observational multicenter study presents results regarding continuous and non-continuous REBOA with favorable outcomes. However, further prospective studies are needed to be able to draw conclusions on morbidity and mortality.

18F-fluorodeoxyglucose specimen-positron emission mammography delineates tumour extension in breast-conserving surgery: Preliminary results.

OBJECTIVES: We aimed to determine whether high-resolution specimen-positron emission mammography (PEM) using fluorodeoxyglucose (18F-FDG) can reveal extension of breast cancer in breast-conserving surgery (BCS), and assess the safety of radiation exposure to medical staff. METHODS: Sixteen patients underwent positron emission tomography, and then BCS with intraoperative frozen section analysis on the same day. Resected specimens with remaining 18F-FDG accumulation were scanned by high-resolution PEM. At least 1 day after surgery, tumour extension was evaluated by three independent experienced readers and by binarized images from the specimen-PEM data. Intraoperative exposure of medical staff to 18F-FDG was measured. RESULTS: Specimen-PEM evaluations of binarized images and the three investigators detected all (100 %, 12/12) invasive lesions and 94.4 % (17/18) of in situ lesions using both methods. The positive predictive value of the accumulated lesions was 74.4 % (29/39) for the binarized images and 82.9 % (29/35) for the three investigators. Analysis of intraoperative frozen sections detected 100 % (2/2) of the margin-positive cases, also detected by both specimen-PEM evaluation methods with no false-positive margin cases. The mean exposure of the medical staff to 18F was 18 µSv. CONCLUSIONS: Specimen-PEM detected invasive and in situ lesions with high accuracy and allowable radiation exposure. KEY POINTS: • Specimen-PEM detected invasive and in situ lesions with high accuracy. • Specimen-PEM predicted complete resection with the same accuracy as frozen section analysis. • Breast-conserving surgery after fluorodeoxyglucose injection was performed with low medical staff exposure.

Significance of measurement of serum trough level and anti-drug antibody of adalimumab as personalised pharmacokinetics in patients with Crohn's disease: a subanalysis of the DIAMOND trial.

BACKGROUND: Significance of monitoring adalimumab trough levels and anti-adalimumab antibodies (AAA) for disease outcome in Crohn's disease (CD) patients remained unclear. AIM: To evaluate the association of adalimumab trough levels and AAA at week 26 with clinical remission at week 52, the effect of azathiopurine on AAA and factors influencing trough levels in CD patients in the DIAMOND trial. METHODS: We performed this study using adalimumab trough levels, AAA at week 26 and 6-thioguanine nucleotide (TGN) in red blood cells at week 12. A multiple regression model and receiver operating analysis was performed to identify factors influencing adalimumab trough levels and AAA, and adalimumab thresholds for predicting disease activity. RESULTS: There was a significant difference of adalimumab trough level at week 26 between patients with disease remission and without at week 52 (7.7 ± 3.3 µg/mL vs 5.4 ± 4.3 µg/mL: P <.001). Adalimumab trough level of 5.0 µg/mL yielded optimal sensitivity and specificity for remission prediction (80.2% and 55.6%, respectively). AAA development at week 26 significantly affected remission at week 52 (P = .021), which was strongly associated with adalimumab trough levels. Female gender and increasing body weight were independently associated with low adalimumab trough levels, and female gender was associated with AAA development. A cut-off 6TGN level of >222.5 p mol/8 ×108 RBCs yielded sensitivity (100%) and specificity (60.6%) for AAA negativity. CONCLUSION: Adalimumab trough levels and AAA occurrence were significantly associated with clinical remission. Higher 6TGN affected AAA negativity. The combination therapy is beneficial in some relevant aspects for CD patients. (UMIN Registration No. 000005146).

Prediction of muscle strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs.

INTRODUCTION: Oncological margins and prognosis are the most important factors for operative planning of soft tissue sarcomas, but prediction of postoperative function is also necessary. The purpose of this study was to predict the knee flexion strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs. MATERIALS AND METHODS: Seventeen patients underwent knee flexor muscle resection for soft tissue sarcoma of the lower limbs between 1991 and 2015. The type of resected muscles was surveyed, knee flexion strength (ratio of affected to unaffected side) was evaluated using the Biodex System isokinetic dynamometer, and differences between the type of resected muscles were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and Short Form 8 (SF-8) were used to assess postoperative function and examine correlations with flexion strength. The cutoff value for flexion strength to predict good postoperative results was calculated by a receiver operating characteristic (ROC) curve and Fisher's exact test. RESULTS: Median flexion strength decreased in the resection of sartorius (97.8%), gracilis (95.4%), gastrocnemius (85.2%; interquartile range (IQR): 85.0-86.2), medial hamstrings (semimembranosus and semitendinosus, 76.2%; IQR: 73.3-78.0), lateral hamstrings (long and short head of biceps femoris, 66.1%; IQR: 65.9-70.4), and bilateral hamstrings (27.3%; IQR: 26.6-31.5). A significant difference was observed between lateral and bilateral hamstrings resection (P=0.049). Flexion strength was associated with lower functional scales (MSTS score, P=0.021; TESS, P=0.008; EQ-5D, P=0.034). Satisfactory function was obtained at a flexion strength cutoff value of 65.7%, and strength remained above the cutoff value up to unilateral hamstrings resection. DISCUSSION: Greater knee flexor muscles resection can result in functional deficits that are associated with decreased flexion strength. If continuity of unilateral hamstrings is maintained, good postoperative results can be expected. LEVEL OF EVIDENCE: IV, retrospective study.

Tumor immune microenvironment and nivolumab efficacy in EGFR mutation-positive non-small-cell lung cancer based on T790M status after disease progression during EGFR-TKI treatment.

BACKGROUND: The efficacy of programmed death-1 blockade in epidermal growth factor receptor gene (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) patients with different mechanisms of acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) is unknown. We retrospectively evaluated nivolumab efficacy and immune-related factors in such patients according to their status for the T790M resistance mutation of EGFR. PATIENTS AND METHODS: We identified 25 patients with EGFR mutation-positive NSCLC who were treated with nivolumab after disease progression during EGFR-TKI treatment (cohort A). Programmed death-ligand 1 (PD-L1) expression and tumor-infiltrating lymphocyte (TIL) density in tumor specimens obtained after acquisition of EGFR-TKI resistance were determined by immunohistochemistry. Whole-exome sequencing of tumor DNA was carried out to identify gene alterations. The relation of T790M status to PD-L1 expression or TIL density was also examined in an independent cohort of 60 patients (cohort B). RESULTS: In cohort A, median progression-free survival (PFS) was 2.1 and 1.3 months for T790M-negative and T790M-positive patients, respectively (P = 0.099; hazard ratio of 0.48 with a 95% confidence interval of 0.20-1.24). Median PFS was 2.1 and 1.3 months for patients with a PD-L1 expression level of ≥1% or <1%, respectively (P = 0.084; hazard ratio of 0.37, 95% confidence interval of 0.10-1.21). PFS tended to increase as the PD-L1 expression level increased with cutoff values of ≥10% and ≥50%. The proportion of tumors with a PD-L1 level of ≥10% or ≥50% was higher among T790M-negative patients than among T790M-positive patients of both cohorts A and B. Nivolumab responders had a significantly higher CD8+ TIL density and nonsynonymous mutation burden. CONCLUSION: T790M-negative patients with EGFR mutation-positive NSCLC are more likely to benefit from nivolumab after EGFR-TKI treatment, possibly as a result of a higher PD-L1 expression level, than are T790M-positive patients.

Clinical significance of the radiological severity score in Mycobacterium avium complex lung disease patients.

SETTING: Practical methods for assessing the radiographic findings of Mycobacterium avium complex lung disease (MAC-LD) have not been established. OBJECTIVE: To identify a correlation between the radiological score and semi-quantitative culture results of respiratory samples, and to assess the prognostic impact of this radiological score in MAC-LD patients. DESIGN: We retrospectively studied 218 MAC-LD patients. Radiographic findings were classified as nodule (N), infiltration shadow (I), cavity (C) and bronchiectasis (E), scored individually according to the area occupied on six lung field divisions, and added to give the radiological severity score. RESULTS: The radiological score positively correlated with the semi-quantitative culture score (P = 0.003). In univariate analysis, the radiological score was a significant negative prognostic factor for overall survival. On multivariate analysis, factors I, C and E were independent negative prognostic factors for overall survival. We compared the prognostic value of the total score of all four factors and the three significant factors (I, C and E) using receiver operating characteristic curve analysis; the corresponding areas under the curves were respectively 0.628 and 0.763 (P < 0.001). CONCLUSIONS: The radiological score correlates with prognosis. The combined score of factors I, C and E may more accurately predict prognosis in MAC-LD patients.

Liver transection using indocyanine green fluorescence imaging and hepatic vein clamping.

BACKGROUND: Three-dimensional (3D) imaging has facilitated liver resection with excision of hepatic veins by estimating the liver volume of portal and hepatic venous territories. However, 3D imaging cannot be used for real-time navigation to determine the liver transection line. This study assessed the value of indocyanine green (ICG) fluorescence imaging with hepatic vein clamping for navigation during liver transection. METHODS: Consecutive patients who underwent liver resection with excision of major hepatic veins between 2012 and 2013 were evaluated using ICG fluorescence imaging after clamping veins and injecting ICG. Regional fluorescence intensity (FI) values of non-veno-occlusive regions (FINon ), veno-occlusive regions (FIVO ) and ischaemic regions (FIIS ) were calculated using luminance analysing software. RESULTS: Of the 21 patients, ten, four and seven underwent limited resection, monosegmentectomy/sectionectomy and hemihepatectomy respectively, with excision of major hepatic veins. Median veno-occlusive liver volume was 80 (range 30-458) ml. Fluorescence imaging visualized veno-occlusive regions as territories with lower FI compared with non-veno-occlusive regions, and ischaemic regions as territories with no fluorescence after intravenous ICG injection. Median FIIS /FINon was lower than median FIVO /FINon (0·22 versus 0·59; P = 0·002). There were no deaths in hospital or within 30 days, and only one major complication. CONCLUSION: ICG fluorescence imaging with hepatic vein clamping visualized non-veno-occlusive, veno-occlusive and ischaemic regions. This technique may guide liver transection by intraoperative navigation, enhancing the safety and accuracy of liver resection.

Optimization of steroid injection intervals for prevention of stricture after esophageal endoscopic submucosal dissection: A randomized controlled trial.

BACKGROUND: Esophageal endoscopic submucosal dissection enables en bloc resection of large superficial esophageal cancer; however, this procedure may induce severe stricture. Intralesional steroid injection is an effective treatment for prevention of stricture after endoscopic resection; however, there have been no studies assessing the duration of such treatment. The aim of this study was to reduce treatment duration and to evaluate the effectiveness of weekly and biweekly steroid injections in preventing esophageal stricture after endoscopic resection. PATIENTS METHOD: We performed a randomized controlled trial comparing patients receiving weekly or biweekly intralesional triamcinolone injections. Patients with a mucosal defect greater than 75% (3/4) of the luminal circumference after esophageal endoscopic submucosal dissection for superficial esophageal cancers were enrolled. The primary endpoint was the duration of steroid injection treatment. RESULTS: The median duration of treatment was 37.0 days in the weekly group and 34.2 days in the biweekly group (P = 0.059). Among patients with a mucosal defect larger than 50 mm, there was a significant difference in the median duration of treatment between the weekly and biweekly groups (42.5 days vs 29.0 days, P = 0.013). CONCLUSION: Biweekly steroid injection of triamcinolone reduces treatment duration, particularly in those with mucosal defects larger than 50 mm. (Acta gastro-enterol. belg., 2016, 79, 315-320).

Changes in tumor expression of HER2 and hormone receptors status after neoadjuvant chemotherapy in 21,755 patients from the Japanese breast cancer registry.

BACKGROUND: We investigate rates of pathologic complete response (pCR) and tumor expression of ER, PgR, HER2 discordance after neoadjuvant chemotherapy using Japanese breast cancer registry data. PATIENTS AND METHODS: Records of more than 300,000 breast cancer cases treated at 800 hospitals from 2004 to 2013 were retrieved from the breast cancer registry. After data cleanup, we included 21,755 patients who received neoadjuvant chemotherapy and had no distant metastases. pCR was defined as no invasive tumor in the breast detected during surgery after neoadjuvant chemotherapy. HER2 overexpression was determined immunohistochemically and/or using fluorescence in situ hybridization. RESULTS: pCR was achieved in 5.7% of luminal tumors (n = 8730), 24.6% of HER2-positive tumors (n = 4403), and 18.9% of triple-negative tumors (n = 3660). Among HER2-positive tumors, pCR was achieved in 31.6% of ER-negative tumors (n = 2252), 17.0% of ER-positive ones (n = 2132), 31.4% of patients who received trastuzumab as neoadjuvant chemotherapy (n = 2437), and 16.2% of patients who did not receive trastuzumab (n = 1966). Of the 2811 patients who were HER2-positive before treatment, 601 (21.4%) had HER2-negative tumors after neoadjuvant chemotherapy, whereas 340 (3.4%) of the 9947 patients with HER2-negative tumors before treatment had HER2-positive tumors afterward. Of the 10,973 patients with ER-positive tumors before treatment, 499 (4.6%) had ER-negative tumors after neoadjuvant chemotherapy, whereas 519 (9.3%) of the 5607 patients who were ER-negative before treatment had ER-positive tumors afterward. CONCLUSION: We confirmed that loss of HER2-positive status can occur after neoadjuvant treatment in patients with primary HER2-positive breast cancer. We also confirmed that in practice, differences in pCR rates between breast cancer subtypes are the same as in clinical trials. Our data strongly support the need for retest ER, PgR, HER2 of surgical sample after neoadjuvant therapy in order to accurately determine appropriate use of targeted therapy.

Lower expression of activating transcription factors 3 and 4 correlates with shorter progression-free survival in multiple myeloma patients receiving bortezomib plus dexamethasone therapy.

Bortezomib (BTZ), a proteasome inhibitor, is widely used in the treatment of multiple myeloma (MM), but a fraction of patients respond poorly to this agent. To identify factors predicting the duration of progression-free survival (PFS) of MM patients on BTZ treatment, the expression of proteasome and endoplasmic reticulum (ER) stress-related genes was quantified in primary samples from patients receiving a combination of BTZ and dexamethasone (BD). Fifty-six MM patients were stratified into a group with PFS<6 months (n=33) and a second group with PFS⩾6 months (n=23). Of the 15 genes analyzed, the expression of activating transcription factor 3 (ATF3) and ATF4 was significantly lower in patients with shorter PFS (P=0.0157 and P=0.0085, respectively). Chromatin immunoprecipitation analysis showed that these ATFs bind each other and transactivate genes encoding the pro-apoptotic transcription factors, CHOP and Noxa, which promote ER stress-associated apoptosis. When either ATF3 or ATF4 expression was silenced, MM cells partially lost sensitivity to BTZ treatment. This was accompanied by lower levels of Noxa, CHOP and DR5. Thus low basal expression of ATF3 and ATF4 may attenuate BTZ-induced apoptosis. Hence, ATF3 and ATF4 could potentially be used as biomarkers to predict efficacy of BD therapy in patients with MM.

Exposure to an atomic bomb explosion is a risk factor for in-hospital death after esophagectomy to treat esophageal cancer.

Esophagectomy, one of the most invasive of all gastrointestinal operations, is associated with a high frequency of postoperative complications and in-hospital mortality. The purpose of the present study was to determine whether exposure to the atomic bomb explosion at Hiroshima in 1945 might be a preoperative risk factor for in-hospital mortality after esophagectomy in esophageal cancer patients. We thus reviewed the outcomes of esophagectomy in 31 atomic bomb survivors with esophageal cancer and 96 controls (also with cancer but without atomic bomb exposure). We compared the incidences of postoperative complications and in-hospital mortality. Of the clinicopathological features studied, mean patient age was significantly higher in atomic bomb survivors than in controls. Of the postoperative complications noted, atomic bomb survivors experienced a longer mean period of endotracheal intubation and higher incidences of severe pulmonary complications, severe anastomotic leakage, and surgical site infection. The factors associated with in-hospital mortality were exposure to the atomic bomb explosion, pulmonary comorbidities, and electrocardiographic abnormalities. Multivariate analysis revealed that exposure to the atomic bomb explosion was an independent significant preoperative risk factor for in-hospital mortality. Exposure to the atomic bomb explosion is thus a preoperative risk factor for in-hospital death after esophagectomy to treat esophageal cancer.

An empirical model for gas phase acidity and basicity estimation.

Gas phase acidity and basicity estimation models have been developed for acidic and basic functional groups of amino acid side-chains and also for a number of small organic molecules. The acidic functional groups include aliphatic and aromatic alcohol, and aliphatic and aromatic carboxylic acid, and the basic functional groups include aliphatic, aromatic and hetero-aromatic amines, and also pyridino-, pyrazolo- and imidazolo-groupings. The models are described in terms of a linear combination of descriptors that highly influence reactivity at the reaction centres of the functional groups. In order to describe the chemical environments of the deprotonating and protonating sites, atomic descriptors such as the effective atomic electronegativity and effective atomic polarizability of the atoms in the reaction field and the electrostatic potentials at the reaction sites have been introduced. The coefficient of determination (r(2)) of each model is above 0.8, apart from the imidazole model. The models are readily applicable, ranging from simple organic molecules to proteins.

Intratumoral concentration of estrogens and clinicopathological changes in ductal carcinoma in situ following aromatase inhibitor letrozole treatment.

BACKGROUND: Estrogens have important roles in ductal carcinoma in situ (DCIS) of the breast. However, the significance of presurgical aromatase inhibitor treatment remains unclear. Therefore, we examined intratumoral concentration of estrogens and changes of clinicopathological factors in DCIS after letrozole treatment. METHODS: Ten cases of postmenopausal oestrogen receptor (ER)-positive DCIS were examined. They received oral letrozole before the surgery, and the tumour size was evaluated by ultrasonography. Surgical specimens and corresponding biopsy samples were used for immunohistochemistry. Snap-frozen specimens were also available in a subset of cases, and used for hormone assays and microarray analysis. RESULTS: Intratumoral oestrogen levels were significantly lower in DCIS treated with letrozole compared with that in those without the therapy. A great majority of oestrogen-induced genes showed low expression levels in DCIS treated with letrozole by microarray analysis. Moreover, letrozole treatment reduced the greatest dimension of DCIS, and significantly decreased Ki-67 and progesterone receptor immunoreactivity in DCIS tissues. CONCLUSION: These results suggest that estrogens are mainly produced by aromatase in DCIS tissues, and aromatase inhibitors potently inhibit oestrogen actions in postmenopausal ER-positive DCIS through rapid deprivation of intratumoral estrogens.

Identification of Toyocamycin, an agent cytotoxic for multiple myeloma cells, as a potent inhibitor of ER stress-induced XBP1 mRNA splicing.

The IRE1α-XBP1 pathway, a key component of the endoplasmic reticulum (ER) stress response, is considered to be a critical regulator for survival of multiple myeloma (MM) cells. Therefore, the availability of small-molecule inhibitors targeting this pathway would offer a new chemotherapeutic strategy for MM. Here, we screened small-molecule inhibitors of ER stress-induced XBP1 activation, and identified toyocamycin from a culture broth of an Actinomycete strain. Toyocamycin was shown to suppress thapsigargin-, tunicamycin- and 2-deoxyglucose-induced XBP1 mRNA splicing in HeLa cells without affecting activating transcription factor 6 (ATF6) and PKR-like ER kinase (PERK) activation. Furthermore, although toyocamycin was unable to inhibit IRE1α phosphorylation, it prevented IRE1α-induced XBP1 mRNA cleavage in vitro. Thus, toyocamycin is an inhibitor of IRE1α-induced XBP1 mRNA cleavage. Toyocamycin inhibited not only ER stress-induced but also constitutive activation of XBP1 expression in MM lines as well as primary samples from patients. It showed synergistic effects with bortezomib, and induced apoptosis of MM cells including bortezomib-resistant cells at nanomolar levels in a dose-dependent manner. It also inhibited growth of xenografts in an in vivo model of human MM. Taken together, our results suggest toyocamycin as a lead compound for developing anti-MM therapy and XBP1 as an appropriate molecular target for anti-MM therapy.