Reprogramming of pyrimidine nucleotide metabolism supports vigorous cell proliferation of normal and malignant T cells

ABSTRACT

Adult T-cell leukemia/lymphoma (ATL) is triggered by infection with human T-cell lymphotropic virus-1 (HTLV-1). Here, we describe the reprogramming of pyrimidine biosynthesis in both normal T cells and ATL cells through regulation of uridine-cytidine kinase 2 (UCK2), which supports vigorous proliferation. UCK2 catalyzes the monophosphorylation of cytidine/uridine and their analogues during pyrimidine biosynthesis and drug metabolism. We found that UCK2 was overexpressed aberrantly in HTLV-1-infected T cells but not in normal T cells. T-cell activation via T-cell receptor (TCR) signaling induced expression of UCK2 in normal T cells. Somatic alterations and epigenetic modifications in ATL cells activate TCR signaling. Therefore, we believe that expression of UCK2 in HTLV-1-infected cells is induced by dysregulated TCR signaling. Recently, we established azacitidine-resistant (AZA-R) cells showing absent expression of UCK2. AZA-R cells proliferated normally in vitro, whereas UCK2 knockdown inhibited ATL cell growth. Although uridine and cytidine accumulated in AZA-R cells, possibly because of dysfunction of pyrimidine salvage biosynthesis induced by loss of UCK2 expression, the amount of UTP and CTP was almost the same as in parental cells. Furthermore, AZA-R cells were more susceptible to an inhibitor of dihydroorotic acid dehydrogenase, which performs the rate-limiting enzyme of de novo pyrimidine nucleotide biosynthesis, and more resistant to dipyridamole, an inhibitor of pyrimidine salvage biosynthesis, suggesting that AZA-R cells adapt to UCK2 loss by increasing de novo pyrimidine nucleotide biosynthesis. Taken together, the data suggest that fine-tuning pyrimidine biosynthesis supports vigorous cell proliferation of both normal T cells and ATL cells.

Home transfusions are implemented using diverse approaches in Japan

BACKGROUND AND OBJECTIVES

Japan's ageing society has increased the need for home healthcare, including home transfusions. We hence aimed to elucidate the purpose and utilization of home transfusions in Japan, which has not been clarified to date.

MATERIALS AND METHODS

Clinics throughout Japan that provide home care and have experience in performing blood transfusions were surveyed. The study period was February to December 2019, and information of patients receiving home red blood cell transfusions, including patient background, pre-transfusion laboratory data and the purpose of the transfusions, was collected.

RESULTS

Haematological malignancies and solid tumours accounted for 70% of the patients' underlying diseases, with the former being significantly more common in urban areas. Regarding the purpose of the home transfusions, haematologists focused on symptom improvement, whereas gastroenterology surgeons focused on life support. Furthermore, maintenance of life was more likely to be the aim in the group of patients with the lowest level of activities of daily living. The main items that were significantly associated with a low haemoglobin level before transfusion included age ≥90 years and a gastroenterologist being the physician in charge.

CONCLUSION

Home transfusions were found to be performed in a restrictive and diverse manner in Japan. Life support is the second most common purpose of home transfusion in Japan, and optimizing effective home transfusion remains a challenge.

HTLV-1 cell-free DNA in plasma as a potential biomarker in HTLV-1 carriers and adult T-cell leukemia-lymphoma

Viral cell-free DNA (cfDNA) in plasma has been widely evaluated for detecting cancer and monitoring disease in virus-associated tumors. We investigated whether the amount of cfDNA of human T-cell leukemia virus type 1 (HTLV-1) correlates with disease state in adult T-cell leukemia-lymphoma (ATL). HTLV-1 cfDNA in aggressive ATL was significantly higher than that in indolent ATL and asymptomatic carriers. Notably, patients with lymphoma type represented higher HTLV-1 cfDNA amount than chronic and smoldering subtypes, though they had no abnormal lymphocytes in the peripheral blood. HTLV-1 cfDNA can be a universal biomarker that reflects the expansion of ATL clones.

Cancer progression by the okadaic acid class of tumor promoters and endogenous protein inhibitors of PP2A, SET and CIP2A

PURPOSE

Okadaic acid class of tumor promoters are transformed into endogenous protein inhibitors of PP2A, SET, and CIP2A in human cancers. This indicates that inhibition of PP2A activity is a common mechanism of cancer progression in humans. It is important to study the roles of SET and CIP2A vis-à-vis their clinical significance on the basis of new information gathered from a search of PubMed.

RESULTS AND DISCUSSION

The first part of this review introduces the carcinogenic roles of TNF-α and IL-1, which are induced by the okadaic acid class of compounds. The second part describes unique features of SET and CIP2A in cancer progression for several types of human cancer: (1) SET-expressing circulating tumor cells (SET-CTCs) in breast cancer, (2) knockdown of CIP2A and increased PP2A activity in chronic myeloid leukemia, (3) CIP2A and epidermal growth factor receptor (EGFR) activity in erlotinib sensitive- and resistant-non-small cell lung cancer, (4) SET antagonist EMQA plus radiation therapy against hepatocellular carcinoma, (5) PP2A inactivation as a common event in colorectal cancer, (6) prostate cancer susceptibility variants, homeobox transcription factor (HOXB13 T) and CIP2A T, and (7) SET inhibitor OP449 for pre-clinical investigation of pancreatic cancer. In the Discussion, the binding complex of SET is briefly introduced, and overexpression of SET and CIP2A proteins is discussed in relation to age-associated chronic inflammation (inflammaging).

CONCLUSION

This review establishes the concept that inhibition of PP2A activity is a common mechanism of human cancer progression and activation of PP2A activity leads to effective anticancer therapy.

Usefulness of blood biomarkers for predicting venous thromboembolism in Japanese patients with cancer

Prospective studies on risk factors for the occurrence of venous thromboembolism (VTE) in Asian patients with cancer are limited. Therefore, the present study assessed risk factors for VTE, including multiple blood biomarkers and risk scores consisting of several risk factors, in Japanese patients receiving anticancer drug therapy. In this single-center, prospective, observational study, 200 patients with six types of cancer were enrolled and followed for 1 year to observe the occurrence of symptomatic or asymptomatic VTE. The present study evaluated risk factors, Khorana and Vienna cancer and thrombosis study (CATS) scores at enrollment, and longitudinal data on various blood biomarkers. A Vienna CATS score of ≥3 was significantly associated with VTE occurrence (HR, 2.8; 95% CI, 0.9-8.7; P=0.045). In multivariable analysis, there was a significant association between VTE and the presence of pancreatic cancer (HR, 3.2; 95% CI, 1.1-8.8; P=0.028) and high soluble fibrin (HR, 3.7; 95% CI, 1.1-7.8; P=0.036). Covariate analysis using the propensity score also showed a significant association with hemoglobin dichotomized at <100 g/l (HR, 3.9; 95% CI, 1.1-14.0; P=0.034). Longitudinal data indicated that VTE was associated with soluble fibrin baseline values and an increase in D-dimer levels over time. The present results suggested that blood biomarkers are beneficial for predicting the risk of VTE in Japanese patients with cancer. The present study also provided novel evidence for the importance of measuring soluble fibrin in patients with cancer.

Anti-cancer effect of afatinib, dual inhibitor of HER2 and EGFR, on novel mutation HER2 E401G in models of patient-derived cancer

BACKGROUND

Precision medicine with gene panel testing based on next-generation sequencing for patients with cancer is being used increasingly in clinical practice. HER2, which encodes the human epidermal growth factor receptor 2 (HER2), is a potentially important driver gene. However, therapeutic strategies aimed at mutations in the HER2 extracellular domain have not been clarified. We therefore investigated the effect of EGFR co-targeted therapy with HER2 on patient-derived cancer models with the HER2 extracellular domain mutation E401G, based on our previous findings that this mutation has an epidermal growth factor receptor (EGFR)-mediated activation mechanism.

METHODS

We generated a xenograft (PDX) and a cancer tissue-originated spheroid (CTOS) from a patient's cancer containing an amplified HER2 E401G mutation. With these platforms, we compared the efficacy of afatinib, a tyrosine kinase inhibitor having anti-HER2 and anti-EGFR activity, with two other therapeutic options: lapatinib, which has similar properties but weaker EGFR inhibition, and trastuzumab plus pertuzumab, for which evidence exists of treatment efficacy against cancers with wild-type HER2 amplification. Similar experiments were also performed with H2170, a cell line with wild-type HER2 amplification, to contrast the characteristics of these drug's efficacies against HER2 E401G.

RESULTS

We confirmed that PDX and CTOS retained morphological and immunohistochemical characteristics and HER2 gene profiles of the original tumor. In both PDX and CTOS, afatinib reduced tumor size more than lapatinib or trastuzumab plus pertuzumab. In addition, afatinib treatment resulted in a statistically significant reduction in HER2 copy number at the end of treatment. On the other hand, in H2170 xenografts with wild-type HER2 amplification, trastuzumab plus pertuzumab was most effective.

CONCLUSIONS

Afatinib, a dual inhibitor of HER2 and EGFR, showed a promising effect on cancers with amplified HER2 E401G, which have an EGFR-mediated activation mechanism. Analysis of the activation mechanisms of mutations and development of therapeutic strategies based on those mechanisms are critical in precision medicine for cancer patients.

Management system of home transfusion in Japan: A nationwide survey in 2019

BACKGROUND AND OBJECTIVES

In Japan, there are various opinions on the pros and cons of home transfusion because of safety concerns. We hence aimed to elucidate the safety and availability of home transfusion in Japan, which has not been clarified to date.

MATERIALS AND METHODS

Clinics throughout Japan that provide home care and have experience in performing blood transfusions were surveyed. The analysis period was February to December 2019. Basic information about the clinics, their collaboration system with core hospitals, storage method of red blood cells (RBCs) and the system for the management of patient information regarding transfusion reactions were investigated.

RESULTS

Detailed information was obtained regarding the implementation of home transfusions by 51 clinics. The proportion of home care clinics performing home transfusions was 17.6%, and they were more frequently performed in urban regions. Approximately half of the clinics collaborated with a core hospital for emergency responses to transfusion reactions. At 84% of the clinics, RBC units were stored in refrigerators that were not exclusively allocated to blood storage. Nurses and family members were involved as patient attendants in 83% and 77% of the home transfusions, respectively. No serious transfusion reactions were reported among the 150 patients in 2019, nor the 623 patients up to 2018.

CONCLUSION

From data on its availability and safety, home transfusions are considered to be in the developing phase in Japan. Increased cooperation between hospitals and clinics is crucial towards improving the home transfusion system in Japan in the future.

Clinical utility of comprehensive genomic profiling in Japan: Result of PROFILE-F study

Introduction

Clinical sequencing has provided molecular and therapeutic insights into the field of clinical oncology. However, despite its significance, its clinical utility in Japanese patients remains unknown. Here, we examined the clinical utility of tissue-based clinical sequencing with FoundationOne® CDx and FoundationOne® Heme. Between August 2018 and August 2019, 130 Japanese pretreated patients with advanced solid tumors were tested with FoundationOne® CDx or FoundationOne® Heme.

Results

The median age of 130 patients was 60.5 years (range: 3 to 84 years), and among them, 64 were males and 66 were females. Major cancer types were gastrointestinal cancer (23 cases) and hepatic, biliary, and pancreatic cancer (21 cases). A molecular tumor board had been completed on all 130 cases by October 31, 2019. The median number of gene alterations detected by Foundation testing, excluding variants of unknown significance (VUS) was 4 (ranged 0 to 21) per case. Of the 130 cases, one or more alterations were found in 123 cases (94.6%), and in 114 cases (87.7%), actionable alterations with candidates for therapeutic agents were found. In 29 (22.3%) of them, treatment corresponding to the gene alteration was performed. Regarding secondary findings, 13 cases (10%) had an alteration suspected of a hereditary tumor. Of the 13 cases, only one case received a definite diagnosis of hereditary tumor.

Conclusions

Our study showed that clinical sequencing might be useful for detecting gene alterations in various cancer types and exploring treatment options. However, many issues still need to be improved.

Correlation of Strain Classification with IR Biotyper and Molecular Epidemiological Method of Pseudomonas aeruginosa

INTRODUCTION

From 2018, IR Biotyper (IRBT; Bruker Daltonik GmbH, Germany) based on the Fourier transform infrared spectrophotometer has begun to be introduced as a new strain classification method in the field of clinical microbiological examination. We compared it with molecular epidemiology method to evaluate the usefulness of strain classification by IRBT.

METHOD

Homology of strain classification with molecular epidemiology method (Multilocus Sequencing Typing; MLST and PCR-based ORF Typing; POT) for 48 strains of Pseudomonas aeruginosa with different detection times from multiple institutions to evaluate the accuracy of IRBT was compared.

RESULTS

IRBT used "KBM" SCD agar medium for preculture and was classified into 12 types when classified by Cut-off value 0.181, 8 types by MLST, and 13 types by POT. In the Adjusted Wallace between IRBT and molecular epidemiology method, MLST was 0.458 (95% CI; 0.295 to 0.620) and POT was 0.330 (95% CI; 0.135 to 0.525), indicating a discrepancy in strain classification.

CONCLUSION

No correlation was found between IRBT and the classification results by the molecular epidemiology method. In the molecular epidemiology method, strains are classified by matching only specific gene regions, but IRBT irradiates a sample with an infrared laser and classifies the strains according to the difference in absorption spectrum according to the molecular structure, so the measurement principle is different. When classifying strains by IRBT, it is desirable to grasp the clinical information of the detected strains and to target multiple strains isolated at the same facility at the same time.

HTLV-1 infection promotes excessive T cell activation and transformation into adult T cell leukemia/lymphoma

Human T cell leukemia virus type 1 (HTLV-1) mainly infects CD4+ T cells and induces chronic, persistent infection in infected individuals, with some developing adult T cell leukemia/lymphoma (ATL). HTLV-1 alters cellular differentiation, activation, and survival; however, it is unknown whether and how these changes contribute to the malignant transformation of infected cells. In this study, we used single-cell RNA-sequencing and T cell receptor-sequencing to investigate the differentiation and HTLV-1-mediated transformation of T cells. We analyzed 87,742 PBMCs from 12 infected and 3 uninfected individuals. Using multiple independent bioinformatics methods, we demonstrated the seamless transition of naive T cells into activated T cells, whereby HTLV-1-infected cells in an activated state further transformed into ATL cells, which are characterized as clonally expanded, highly activated T cells. Notably, the greater the activation state of ATL cells, the more they acquire Treg signatures. Intriguingly, the expression of HLA class II genes in HTLV-1-infected cells was uniquely induced by the viral protein Tax and further upregulated in ATL cells. Functional assays revealed that HTLV-1-infected cells upregulated HLA class II molecules and acted as tolerogenic antigen-presenting cells to induce anergy of antigen-specific T cells. In conclusion, our study revealed the in vivo mechanisms of HTLV-1-mediated transformation and immune escape at the single-cell level.

Role of TNF-α-Inducing Protein Secreted by Helicobacter pylori as a Tumor Promoter in Gastric Cancer and Emerging Preventive Strategies

The tumor necrosis factor-α (TNF-α)-inducing protein (tipα) gene family, comprising Helicobacter pylori membrane protein 1 (hp-mp1) and tipα, has been identified as a tumor promoter, contributing to H. pylori carcinogenicity. Tipα is a unique H. pylori protein with no similarity to other pathogenicity factors, CagA, VacA, and urease. American H. pylori strains cause human gastric cancer, whereas African strains cause gastritis. The presence of Tipα in American and Euro-Asian strains suggests its involvement in human gastric cancer development. Tipα secreted from H. pylori stimulates gastric cancer development by inducing TNF-α, an endogenous tumor promoter, through its interaction with nucleolin, a Tipα receptor. This review covers the following topics: tumor-promoting activity of the Tipα family members HP-MP1 and Tipα, the mechanism underlying this activity of Tipα via binding to the cell-surface receptor, nucleolin, the crystal structure of rdel-Tipα and N-terminal truncated rTipα, inhibition of Tipα-associated gastric carcinogenesis by tumor suppressor B-cell translocation gene 2 (BTG2/TIS21), and new strategies to prevent and treat gastric cancer. Thus, Tipα contributes to the carcinogenicity of H. pylori by a mechanism that differs from those of CagA and VacA.

Clinical significance of soluble CADM1 as a novel marker for adult T-cell leukemia/lymphoma

Adult T-cell leukemia/leukemia (ATLL) is an aggressive peripheral T-cell malignancy, caused by infection with the human T-cell leukemia virus type 1 (HTLV-1). We recently showed that the cell adhesion molecule 1 (CADM1), a member of the immunoglobulin superfamily, is specifically and consistently overexpressed in ATLL cells, and functions as a novel cell surface marker. In this study, we first show that a soluble form of CADM1 (sCADM1) is secreted from ATLL cells by mainly alternative splicing. After developing the Alpha linked immunosorbent assay (AlphaLISA) for sCADM1, we show that plasma sCADM1 concentrations gradually increased during disease progression from indolent to aggressive ATLL. Although other known biomarkers of tumor burden such as soluble interleukin-2 receptor α (sIL-2Rα) also increased with sCADM1 during ATLL progression, multivariate statistical analysis of biomarkers revealed that only plasma sCADM1 was selected as a specific biomarker for aggressive ATLL, suggesting that plasma sCADM1 may be a potential risk factor for aggressive ATLL. In addition, plasma sCADM1 is a useful marker for monitoring response to chemotherapy as well as for predicting relapse of ATLL. Furthermore, the change in sCADM1 concentration between indolent and aggressive type ATLL was more prominent than the change in the percentage of CD4⁺CADM1⁺ ATLL cells. As plasma sCADM1 values fell within normal ranges in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients with higher levels of serum sIL-2Rα, the measurement of sCADM1 may become a useful tool to discriminate between ATLL and other inflammatory diseases, including HAM/TSP.

Diagnostic Accuracy of FibroScan and Factors Affecting Measurements

Evaluating liver steatosis and fibrosis is important for patients with non-alcoholic fatty liver disease. Although liver biopsy and pathological assessment is the gold standard for these conditions, this technique has several disadvantages. The evaluation of steatosis and fibrosis using ultrasound B-mode imaging is qualitative and subjective. The liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) determined using FibroScan are the evidence-based non-invasive measures of liver fibrosis and steatosis, respectively. The LSM and CAP measurements are carried out simultaneously, and the median values of more than ten valid measurements are used to quantify liver fibrosis and steatosis. Here, we demonstrate that the reliability of the LSM depends on the interquartile range to median ratio (IQR/Med), but CAP values do not depend on IQR/Med. In addition, the LSM is affected by inflammation, congestion, and cholestasis in addition to fibrosis, while CAP values are affected by the body mass index in addition to steatosis. We also show that the M probe provides higher LSM values but lower CAP values than the XL probe in the same population. However, there was no statistically significant difference between the diagnostic accuracies of the two probes. These findings are important to understand the reliability of FibroScan measurements and the factors influencing measurement values for all patients.

Rapid detection method of carbapenemase-producing Enterobacteriaceae by MALDI-TOF MS with imipenem/cilastatin (KB) disc and zinc sulfate solution

INTRODUCTION

Carbapenemase-producing Enterobacteriaceae (CPE) is a major global health threat, and development of rapid detection methods is desired. Here, we established a cost-effective and relatively rapid CPE detection method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

METHODS

We examined 134 CPE strains (IMP-type, NDM-type, VIM-type, KPC-type, OXA-48-like-type, and GES-type) and 107 non-CPE strains, previously confirmed by genetic tests. The proposed MALDI-TOF MS method involves mixing of a carbapenem drug [here, the commercially available imipenem (IPM) KB disc] and the bacterial strains to be tested, and the consequent drug hydrolysis owing to bacterial carbapenemase activity is confirmed by a waveform spectrum before and after 2 h of the mixing. As metallo-beta-lactamases require zinc in their active site, the false-negatives obtained from our method were cultured in presence of zinc sulfate solution and tested again.

RESULTS

Based on the presence or absence of the IPM (+cyano-4-hydroxy-cinnamic acid)-specific waveform peak near 489.45 m/z (±500 ppm), the detection sensitivity and specificity of our method for CPE were determined to be 94.8% and 91.6%, respectively. Seven false-negatives of IMP-type (4), VIM-type (2), and GES-type (1) were found, of which the IMP- and VIM-types tested positive as CPE after culture with zinc sulfate solution. Thus, the overall detection sensitivity improved to 99.3%.

CONCLUSION

Our study proposes a new approach for CPE detection using MALDI-TOF MS. Moreover, we propose cultivation of test strains with zinc sulfate solution for efficient detection of IMP-type CPE, not only for MALDI-TOF MS, but also for other detection methods.

Diagnostic accuracy of FibroScan-AST score to identify non-alcoholic steatohepatitis with significant activity and fibrosis in Japanese patients with non-alcoholic fatty liver disease: Comparison between M and XL probes

AIM

Recently, FibroScan-AST (FAST) score was reported to be effective for identifying non-alcoholic steatohepatitis (NASH) with significant activity and fibrosis in non-alcoholic fatty liver disease (NAFLD). The aim of this study was to confirm the diagnostic accuracy of FAST score of Japanese patients and compare the cut-off values and diagnostic accuracy between the FibroScan M and XL probes.

METHODS

Eighty-two and 84 patients were included the verification and validation sets, respectively. All patients were diagnosed with NAFLD by biopsy by two central expert pathologists. Liver stiffness measurements and controlled attenuation parameter were carried out, and diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

No significant difference existed in FAST score between the M and XL probes (0.489 vs. 0.483, P = 0.187). No significant difference existed in the area under the ROC between the two probes (M, 0.7598; XL, 0.7614; P = 0.958). According to the Youden index, the cut-off value using the M probe was 0.57 with 68.2% sensitivity and 78.3% specificity. For the XL probe, the cut-off value was 0.56 with 68.2% sensitivity and 73.3% specificity. To obtain sensitivity and specificity values higher than 90%, cut-off values of 0.35 and 0.66 were chosen for the M probe and 0.32 and 0.63 were chosen for the XL probe.

CONCLUSIONS

There was no significant difference in diagnostic accuracy of FAST score between the FibroScan M and XL probes. The FAST score can be used to identify NASH with significant risk in Japanese patients regardless of probe selection.

Development of an application for management of drug holidays in perioperative periods

Before surgery and other invasive treatments, decisions must be made on whether to discontinue drugs and provide appropriate drug holidays especially for antithrombotic drugs, and this is made difficult by the large number of available drugs and associated guidelines. We have therefore developed an online application for perioperative drug discontinuation and resumption management, named Saga Application for Management of Drug Holidays in PeriOperative Periods (SAMPOP).Multidisciplinary medical staff at Saga University Hospital (SUH) worked together to build an evidence-based Perioperative Drug Discontinuation Management Database (PDDMD) and developed the user-friendly SAMPOP online application via preliminary verification at SUH. From September 2018 to February 2020, 420 medical staff at SUH, including physicians, nurses, and pharmacists, installed and tested SAMPOP.Rate per surgical procedure for forgetting to discontinue antithrombotic drugs preoperatively decreased from 0.18% to 0.09% as of August 2019, 12 months after the introduction of SAMPOP (P = .1359). In addition, six months later, it decreased further to 0.03% as of February 2020 (P = .0436). Forgetting to resume antithrombotic drugs postoperatively decreased from 0.20% to 0.02% as of August 2019, 12 months after the introduction of SAMPOP (P = .0008). There was no case of forgetting to resume the medication in the last 6 months.SAMPOP may be useful for management of drug holidays in the clinic and warrants further evaluation of its safety and efficacy.

Clinical impact of the CONUT score in patients with multiple myeloma

Novel anti-myeloma drugs have significantly improved the overall survival (OS) of patients with multiple myeloma (MM). However, not all MM patients treated with these drugs show survival benefits, and biologic and genetic prognostic factors are insufficient to predict the response to treatment. Decreasing treatment-related complications is important to improve the efficacy of treatment in patients with MM. The Controlling Nutritional Status (CONUT) score is a screening method for poor nutritional status, which is associated with poor prognosis in several cancers because it increases the rate of treatment-related complications. We retrospectively analyzed the OS of 64 patients with symptomatic MM and evaluated the correlation between the CONUT score and patient prognosis in MM. The median age at diagnosis was 66 years, and multivariate analysis showed that a high CONUT score (≥ 5; hazard ratio, 3.937; 95% confidence interval, 1.214-12.658; P = 0.022) was an independent prognostic risk factor. Subgroup analysis was performed according to patient age because the choice of treatment strategy, particularly autologous peripheral blood stem cell transplantation (auto-PBSCT), can vary depending on age in MM patients. Younger patients (< 65 years old) who received auto-PBSCT and had a lower CONUT score (0-3) showed a significantly better survival outcome than those with a higher CONUT score (≥ 4) (median OS, not reached vs. 64.1 months; P = 0.011). The CONUT score is simple to calculate and provides a useful prognostic indicator in patients with MM, especially transplant-eligible patients.

Primary Chest Wall MYC/BCL6 Double-hit Lymphoma with t (3;7) (q27;p12) and t (8;14) (q24;q32) Translocations

Primary chest wall lymphoma is rare and typically associated with chronic pleural inflammation. Double-hit lymphoma (DHL), which is defined as aggressive mature B-cell lymphoma with MYC and BCL2 or BCL6 rearrangements, is a highly aggressive malignancy that tends to have extranodal involvement and is resistant to standard immunochemotherapy. We herein report a 55-year-old man with no history of chronic pleural inflammation, diagnosed with primary chest wall DHL with MYC/BCL6 rearrangement, and harboring a unique BCL6 translocation, t (3;7) (q27;p12). After six courses of intensive chemotherapy, he has achieved complete remission. To our knowledge, this is the first case report of primary chest wall DHL.

Abstract 855: Analysis of a novel variant of HER2 detected by clinical sequencing in cancer of unknown primary

A patient with cancer of unknown primary underwent an NGS-based multiplex gene assays (OncoPrime). As a result, a novel variant of HER2 (E401G) which is a missense alteration located in the extracellular domain of the HER2 protein was detected. This alteration has not been reported (COSMIC, Nov 2018) and its effect on protein function is unknown. Sanger sequencing using genomic DNA from peripheral blood sample showed that the variant was a somatic variant. HER2 E401G variant was confirmed by Sanger sequencing using genomic DNA extracted from the formalin-fixed paraffin-enbedded tumor tissues. In spite of somatic variant, the variant allele frequency was relatively high (55.8%). This result suggested the amplification of HER2 gene, FISH analysis confirmed the copy number gain of HER2 gene (21 copies). The prediction tools in silico (SIFT, PolyPhen-2 and PROVEAN) suggested pathogenicity of the variant, so we are now performing the functional analysis of the mutant HER2 protein. Many variants of unknown significance have been identified through clinical sequencing, establishing a database of integrated information of variant is essential to implement precision medicine of oncology. This study was approved by the Ethics Committee and the patient provided written informed consent for the use of genomic and clinical data for research purposes.

Citation Format: Yohei Harada, Tomomi Kashiwada, Akemi Sato, Tomonori Abe, Chiho nakashima, Eisaburo Sueoka, Shinya Kimura, Naoko Sueoka-Aragane. Analysis of a novel variant of HER2 detected by clinical sequencing in cancer of unknown primary [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 855.

Abstract 420: Characteristics of circulating tumor DNA in lung cancer patients

Liquid biopsy using circulating tumor DNA (ctDNA) has been spread world-wide. We established fully automatic sensitive mutation detection system, mutation-biased PCR and quenched probe system (MBP-QP) method, and accomplished multicenter prospective study to investigate the utility of ctDNA in lung cancer patients who acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI). The results of the clinical study showed that ctDNA was frequently detected in lung cancer patients with distant metastasis, and detection of ctDNA was associated with poor prognosis. To investigate the significance of these clinical data, we analyzed biological and clinical characteristics of ctDNA. We examined 130 plasma samples from 92 lung cancer patients in addition to 18 benign pulmonary disease patients and 20 healthy individuals at Saga University Hospital.Circulating free DNA (cfDNA) was extracted from 1000μl plasma by automated DNA extraction system using cellulose magnetic beads. The DNA concentration was quantified by Quantus®, the fluorescent measurement of dsDNA intercalated dye, and the DNA size distribution was analyzed by Bioanalyzer®, capillary electrophoresis system. We found difference of cfDNA size distribution between lung cancer patients and healthy individuals: former showed two peaks of 5kb and 170bp, and latter showed single peak of 170bp. The DNA concentration was higher in lung cancer patients compared to those in benign pulmonary disease patients and healthy individuals. Among lung cancer patients, DNA concentration was increased in those with advanced stages, especially in presence of metastasis. In addition, 5 kb fragments DNA was significantly increased in these cases compared to 170 bp fragments DNA. To investigate which fragment contained tumor-derived DNA, 170 bp and 5 kb fragments were separately isolated, and EGFR mutation, L858R was examined. L858R was detected in both ctDNA fragments, 170 bp and 5 kb, indicating that both sized DNA fragments contain tumor-derived DNA. In order to evaluate DNA resolution, we measured the concentrations of DNase1 and DNase1L3 in plasma, but no significant difference was observed among three groups. Although the 170 bp fragments DNA are well known as an apoptotic product, the origin of 5 kb long fragments DNA has not been clarified. We hypothesized that long fragment DNA has a mechanism to escape from DNase, extracellular vesicles or DNA associated protein. In order to examine that, We analyze whether long fragment DNA is associated with extracellular vesicles or DNA associated protein.

Citation Format: Tomonori Abe, Chiho Nakashima, Akemi Sato, Yohei Harada, Eisaburo Sueoka, Shinya Kimura, Naoko Aragane. Characteristics of circulating tumor DNA in lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 420.

Community-acquired Disseminated Exophiala dermatitidis Mycosis with Necrotizing Fasciitis in Chronic Graft-versus-host Disease

We herein report a case of systemic phaeohyphomycosis by Exophiala dermatitidis (E. dermatitidis) with chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). The patient had been taking oral corticosteroids for years to control the GVHD. Yeast-like fungi were identified in a blood culture, so treatment with micafungin (150 mg/day) was begun, with no improvement. The patient passed away on hospital Day 12. A sequence analysis of rRNA revealed the isolate to be E. dermatitidis. This report brings attention to an emerging mycosis of community-acquired Exophiala species infection in the very-late phase after allogenic HSCT in patients with chronic GVHD.

The concept of the okadaic acid class of tumor promoters is revived in endogenous protein inhibitors of protein phosphatase 2A, SET and CIP2A, in human cancers

PURPOSE

The okadaic acid class of tumor promoters, which are inhibitors of protein phosphatases 1 and 2A (PP1 and PP2A), induced tumor promotion in mouse skin, rat glandular stomach, and rat liver. Endogenous protein inhibitors of PP2A, SET and CIP2A, were up-regulated in various human cancers, so it is vital to review the essential mechanisms of tumor promotion by the okadaic acid class compounds, together with cancer progression by SET and CIP2A in humans.

RESULTS AND DISCUSSION

The first part of this review introduces the okadaic acid class compounds and the mechanism of tumor promotion: (1) inhibition of PP1 and PP2A activities of the okadaic acid class compounds; (2) some topics of tumor promotion; (3) TNF-α gene expression as a central mediator in tumor promotion; (4) exposure to the okadaic acid class of tumor promoters in relation to human cancer. The second part emphasizes the overexpression of SET and CIP2A in cancer progression, and the anticancer activity of SET antagonists as follows: (5) isolation and characterization of SET; (6) isolation and characterization of CIP2A; (7) progression of leukemia with SET; (8) progression of breast cancer with SET and CIP2A; (9) progression of lung cancer with SET; (10) anti-carcinogenic effects of SET antagonists OP449 and FTY720; and also (11) TNF-α-inducing protein of Helicobacter pylori, which is a clinical example of the okadaic acid pathway.

CONCLUSIONS

The overexpression of endogenous protein inhibitors of PP2A, SET and CIP2A, is tightly linked to the progression of various human cancers, as well as Alzheimer's disease.

Investigation of appropriate pre-analytical procedure for circulating free DNA from liquid biopsy

Liquid biopsy with circulating free DNA (cfDNA) is a recommended alternative method of re-biopsy. Quality control with cfDNA is indispensable for precise examinations, and it is desirable to achieve high-quality cfDNA separation. We investigated two issues: the influence of pre-analytical procedures on cfDNA analysis performed as a routine procedure in a standard clinical laboratory, and the extent of deterioration of cfDNA quality due to long-term storage. Comparisons among blood collection tube types, storage temperatures, and periods of blood separation were performed in terms of cfDNA quantification, cfDNA size distribution, and detection of EGFR mutations. Quality of cfDNA was better with collection tubes containing 3.2% sodium citrate than with those containing EDTA 2K, and was maintained with storage at 4° C for up to 72 h after blood collection, equivalent to results with cell-stabilizing blood collection tubes. Analysis of cfDNA stored for 7 years showed that samples with low allele frequency (AF) deteriorated more readily than samples with high AF. Despite the same storage period and extraction method, AF of plasma stored for 7 years was remarkably lower than that of cfDNA. However, deterioration due to long-term plasma storage was overcome by changing the DNA extraction method from a silica membrane spin column to a cellulose magnetic beads system. These results can guide the establishment of standardized pre-analytical procedures for liquid biopsy with cfDNA.

Identification of the BRAF V600E mutation in Japanese patients with hairy cell leukemia and related diseases using a quenching probe method

Hairy cell leukemia (HCL) is a rare B-cell lymphoid malignancy that is difficult to distinguish from other morphological variants. The frequency of HCL has not been determined accurately in Japan. Recent studies revealed that the BRAF V600E mutation is the causal genetic event in HCL. We assessed the BRAF mutation in Japanese patients with HCL and related diseases using the quenching probe (QP) method, a single-nucleotide polymorphism detection system, and evaluated the incidence rate of HCL among Japanese patients with chronic lymphocytic leukemia, and related diseases. We identified 18 cases (33.3%) harboring the BRAF mutation among 54 patients diagnosed with, or suspected of having HCL. Of BRAF V600E-positive patients, 7 were only detected using the QP method, not by direct sequencing, whereas 11 were positive using both tests. In a larger cohort of Japanese patients diagnosed with chronic lymphoid leukemia or related diseases, the frequency of HCL was 4%. Patients with the BRAF V600E mutation had a significantly higher frequency of neutropenia, thrombocytopenia, and elevated soluble interleukin-2 receptor and common B-cell surface markers than patients without the mutation. Our results confirm that BRAF V600E-positive HCL is a relatively rare disorder in the Japanese leukemia patient population.

Incidence of aspiration pneumonia during hospitalization in Japanese hospitalized cases did not increase whereas concern factors were exacerbated in a time-dependent manner: analysis of Diagnosis Procedure Combination (DPC) data

This study aimed i) to investigate about items with high relevance for aspiration pneumonia during hospitalization among cases evaluated using Diagnosis Procedure Combination data, and ii) to determine whether the concern factors for aspiration pneumonia during hospitalization were exacerbated with the trend of the time. The Diagnosis Procedure Combination data were gathered from 2010 through to 2015 with 63,390 cases at Saga University Hospital. The occurrence of concern factors of aspiration pneumonia during hospitalization were compared in the two time periods set (2010-2012 and 2013-2015). The concern factors included: male, age, dysphagia at admission and during hospitalization, use and days in the emergency care unit or high care unit, use of the intensive care unit, and use of an ambulance. Age, dysphagia, and use of the intensive care unit were time-dependently exacerbated. The incidence of aspiration pneumonia during hospitalization in hospitalized cases did not differ between years 2010-2012 and 2013-2015. Aspiration pneumonia during hospitalization complicated with surgery and number days in the emergency care unit or high care unit diminished in years 2013-2015. Despite an increased concern of aspiration pneumonia during hospitalization, the complication rate of aspiration pneumonia during hospitalization did not increase.

Abstract 3646: Investigation of origin of circulating free DNA: Is exosomal DNA the carrier

The usefulness of circulating free DNA (cfDNA) for analysis of genetic alterations is largely accepted. We accomplished multicenter prospective study to investigate sequential change of cfDNA in lung cancer patients who acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors. The detection frequency was elevated as cancer progressed, and the prognosis of the patients in which cfDNA was detected was poorer than those not detected. These results suggest that appearance of cfDNA was associated with tumor progression. To verify that, animal experiment using immunodeficient mice, NOJ mice, was performed. After transplantation with human lung cancer cell line, H1975 carrying EGFR L858R, and T790M, into dorsal flanks of these mice, systemic metastasis occurred. cfDNA was sequentially analyzed, resulting that the amount of cfDNA was correlated with tumor burden and metastatic status. In spite of these results, origin, kinetics or possible function on tumor progression of cfDNA has not been elucidated. We have reported there were large sized DNA fragments, around 5 Kb, which is longer than 170 bp of cfDNA conventionally detected in peripheral blood of advanced cancer patients. Exosomes, extracellular vesicles detected in peripheral blood has been reported to be involved in tumor progression through vesicle-mediated communication. In general, exosomes deliver protein, lipid and RNA, and few DNA was contained. However, some researchers reported a large proportion of cfDNA was localized in exosomes. To investigate the origin and localization of cfDNA in peripheral blood, we analyzed relationship between cfDNA and exosomal DNA. We isolated both of cfDNA and exosomal DNA simultaneously, from plasma of healthy individuals and advanced non-small cell lung cancer patients, and compared the DNA yield, DNA size distribution and EGFR mutation detection rate. Localization of DNA in exosome is also investigated using fluorescent dye. We used Total Exosome Isolation Kit® from plasma with/without proteinase K for isolation of exosome from 200 uL plasma, and extracted DNA using Maxwell RSC® circulating cell free DNA cartridge. The proportion of exosomal DNA /cfDNA (e/c DNA ratio) varied individually, but e/c DNA ratio was lower in plasma from cancer patients than healthy individuals. However, large sized fragments of cfDNA were observed in exosomal DNA in lung cancer patients. These results suggest that exosomal DNA might have some interaction with large sized cfDNA fragments observed in plasma isolated from advanced cancer patients.

Citation Format: Chiho Nakashima, Tomonori Abe, Akemi Sato, Tomomi Nakamura, Kazutoshi Komiya, Eisaburo Sueoka, Shinya Kimura, Naoko Sueoka-Aragane. Investigation of origin of circulating free DNA: Is exosomal DNA the carrier [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3646.

Cancer Prevention with Green Tea and Its Principal Constituent, EGCG: from Early Investigations to Current Focus on Human Cancer Stem Cells

Cancer preventive activities of green tea and its main constituent, (-)-epigallocatechin gallate (EGCG) have been extensively studied by scientists all over the world. Since 1983, we have studied the cancer chemopreventive effects of EGCG as well as green tea extract and underlying molecular mechanisms. The first part of this review summarizes ground-breaking topics with EGCG and green tea extract: 1) Delayed cancer onset as revealed by a 10-year prospective cohort study, 2) Prevention of colorectal adenoma recurrence by a double-blind randomized clinical phase II trial, 3) Inhibition of metastasis of B16 melanoma cells to the lungs of mice, 4) Increase in the average value of Young's moduli, i.e., cell stiffness, for human lung cancer cell lines and inhibition of cell motility and 5) Synergistic enhancement of anticancer activity against human cancer cell lines with the combination of EGCG and anticancer compounds. In the second part, we became interested in cancer stem cells (CSCs). 1) Cancer stem cells in mouse skin carcinogenesis by way of introduction, after which we discuss two subjects from our review on human CSCs reported by other investigators gathered from a search of PubMed, 2) Expression of stemness markers of human CSCs compared with their parental cells, and 3) EGCG decreases or increases the expression of mRNA and protein in human CSCs. On this point, EGCG inhibited self-renewal and expression of pluripotency-maintaining transcription factors in human CSCs. Human CSCs are thus a target for cancer prevention and treatment with EGCG and green tea catechins.

Deep sequencing of the T cell receptor visualizes reconstitution of T cell immunity in mogamulizumab-treated adult T cell leukemia

Although the anti-CCR4 antibody mogamulizumab (moga) shows striking antitumor activity against adult T cell leukemia (ATL), it can also cause fatal immunological pathology such as severe skin rash and graft-versus-host disease, which might be attributed to depletion of CCR4⁺ regulatory T cells. We previously showed that next generation sequencing enables precise analysis of the T cell receptor (TCR) repertoire, and we here used the technique to reveal the immunological dynamics in moga-treated ATL patients. Treatment with moga resulted in remarkable reduction or elimination of clonal cells, and enhanced reconstitution of non-tumor polyclonal CD4⁺ T cells and oligoclonal CD8⁺ T cells. Interestingly, cutaneous T cells infiltrating moga-related skin rashes did not share the same major clones in peripheral blood, which minimizes the possibility of cross-reaction. Thus, deep sequencing of the TCR can reveal the immune reconstitution of moga-treated ATL and provides powerful insights into its mode of action.

Abstract 2751: Automatic DNA extraction system can improve the EGFR point mutation detection rate of liquid biopsy

The usefulness of liquid biopsy to detect mutations from cancer patients has been well recognized today. However, because the mutation detection rates from plasma DNA were relatively lower than those of tissue re-biopsy, its clinical utility has not been confirmed yet. As previously we reported, we have developed fully automatic high-sensitive point mutation detecting system named mutation-biased PCR and quenched probe (MBP-QP) system for liquid biopsy. Recently, the importance of pre-analytical procedures for plasma DNA anazysis has been highlighted. In this study, we examined whether the automatic DNA extraction system can improve the mutation detection rate in our MBP-QP system. Sixty-one plasma samples were obtained from advanced non-small cell lung cancer patients, and plasma DNA extraction was performed from 200μl plasma by manually (200-M), and 200μl (200-A), 1000μl (1000-A) plasma by automatically. We used silica membrane spin column system for manual DNA extraction, and magnet beads system for automatic DNA extraction procedure. The median DNA concentrations quantified by quantitative real-time PCR of 200-M, 200-A, 1000-A were 4.92, 6.00, 20.1 ng/mL plasma, respectively. In terms of the epidermal growth factor receptor (EGFR) L858R point mutation detection, the sensitivity of 200-M, 200-A, 1000-A were 36.6%, 58.5%, 77.5%, that of the specificity were 93.3%, 100%, 96.7%, and the concordance rates were 60.6%, 76.1%, 85.7%, respectively. The size distribution of automatically extracted plasma DNA represented two peaks characteristics at 170 bp and 5 kb. In this study, we indicate the automatic DNA extraction can improve mutation detection rates in plasma DNA.

Citation Format: Chiho Nakashima, Akemi Sato, Tomonori Abe, Tomomi Nakamura, Kazutoshi Komiya, Eisaburo Sueoka, Shinya Kimura, Naoko Sueoka-Aragane, Junichi Kato, Mitsuharu Hirai. Automatic DNA extraction system can improve the EGFR point mutation detection rate of liquid biopsy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2751. doi:10.1158/1538-7445.AM2017-2751

Plasma T790M and HGF as potential predictive markers for EGFR-TKI re-challenge

Re-challenge with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) has been suggested to potentially improve survival in certain populations of patients with advanced lung cancer, but predictive markers for the success of EGFR-TKI re-challenge have not been identified. The present study analyzed 16 re-challenges with EGFR-TKI undertaken in 12 patients with lung adenocarcinoma by investigating T790M and hepatocyte growth factor (HGF) in plasma coupled with clinical characteristics. EGFR mutations in plasma DNA were detected using the wild inhibiting PCR and quenched probe system for exon 19 deletions, and T790M and L858R were detected using the mutation-biased PCR and quenched probe system. HGF levels in the plasma were measured by enzyme-linked immunosorbent assay, and the ratio of HGF levels prior to re-challenge to those prior to the previous EGFR-TKI treatment was calculated. Two re-challenges demonstrated partial response, six remained as stable disease and eight had progressive disease (PD). A total of 4 of the 5 patients with a history of T790M positivity based on plasma DNA levels had PD. A total of 7 of the 8 patients who had ≥1.5-fold elevation of HGF prior to re-challenge with EGFR-TKI suffered PD. Elevation of the HGF ratio to ≥1.5 was significantly associated with poor response to EGFR-TKI re-challenge. Having no history of T790M and an HGF ratio <1.5 was significantly associated with a positive response to EGFR-TKI re-challenge. A combination of T790M detection and HGF quantification using plasma is a potentially useful assay system for predicting the effect of EGFR-TKI re-challenge. Future prospective studies are required to confirm the predictive validity of these markers.

[Japanese Biobanks: Current Status, Problems, and Future Challenges]

A biobank is a facility that collects and manages biological specimens such as tissues, cells, and blood de- rived from living organisms. In addition to these materials, the biobank can also be used for storing urine, body fluid, DNA, and intracellular structures like exosomes. The initial objective of stocking these materials was mainly for research purposes, such as searching for biomarkers and genes responsible for diseases, but due to the rapid clinical application of molecular-targeted therapy and personalized medicine based on genetic information, biobanking is now becoming one of the fundamental efforts indispensable for clinical practice. In Japan, the importance of stocks of biological samples has been recognized for a long time, and biobanking was implemented in various medical institutions alone or in several medical departments, but recently the organization of biobanks has been developed and they are carrying out activities according to each purpose. 1. Biobank as a national project Biobank, Japan 2. National Center Biobank Network NCBN 3. Biobanks operated by each institution other than those mentioned above As a part of Japan's research strategy, the Japan Agency for Medical Research and Development (AMED) has promoted the "Genomic medicine realization project", and the construction of medical biobanks is one of the major projects in the strategy. In this special issue, the current status of biobanks is introduced and problems and future challenges as a national project are discussed.

[Clinical Hematology for Specialists of Clinical Laboratory Medicine]

The knowledge and skills of clinical hematology necessary for clinical laboratory medicine are different from the knowledge required for the hematological specialists or general physicians. A wide range of knowledge and comprehensive skills to connect the sub-specialty and hematological specialist are required. To do so, comprehensive understanding such as, (1) how to assess the results of blood testing in a relative- ly frequent disease, (2) understanding of specific diseases that require rapid clinical judgment and consulta- tion, (3) the latest diagnostic techniques, including genetic diagnosis, (4) the knowledge of companion diag- nostic techniques necessary for molecular targeted therapy and molecular immunotherapy, are required. However, it is not easy to understand the rapid progress in diagnostic techniques and treatment strategies even in hematological specialists. Therefore, the following points are presented in the seminar; understand- ing of boundary for normal and abnormal findings, evaluation criteria for rapid assessment and report, the feature of hematological malignancies tight cooperation is needed with hematological specialist. In this paper, the role of the specialists on clinical laboratory medicine as a "mediator" in the clinical hema- tology is summarized, especially in anemia and coagulation disorders. [Review].

Torin2 Potentiates Anticancer Effects on Adult T-Cell Leukemia/Lymphoma by Inhibiting Mammalian Target of Rapamycin

BACKGROUND

Torin2 is a second-generation ATP-competitive inhibitor of the mammalian target of rapamycin (mTOR). Dysregulation of mTOR signaling pathway, consisting of mTOR complexes mTORC1 and mTORC2, is a promising therapeutic target in some human malignancies. We examined antitumor effects of Torin2 in adult T-cell leukemia/lymphoma (ATL)-related cell lines compared to those of rapamycin, a classical mTOR inhibitor.

MATERIALS AND METHODS

Cell growth was monitored by detecting viable cells with Cell Counting Kit-8 or trypan blue. Cell cycle was studied by flow cytometric analysis. The phosphorylation status of proteins in the mTOR signaling pathway was examined by western blot analysis.

RESULTS

Torin2 exhibited greater efficacy in cell growth inhibition than rapamycin, associated with a strong reduction of phosphorylated v-akt murine thymoma viral oncogene homolog (AKT) (Ser 473), that is downstream of mTORC2.

CONCLUSION

Since mTORC2 activates AKT, Torin2 might inhibit both mTORC1 and mTORC2, resulting in stronger growth inhibition of ATL cells.

2-Hydroxypropyl-β-Cyclodextrin Acts as a Novel Anticancer Agent

2-Hydroxypropyl-β-cyclodextrin (HP-β-CyD) is a cyclic oligosaccharide that is widely used as an enabling excipient in pharmaceutical formulations, but also as a cholesterol modifier. HP-β-CyD has recently been approved for the treatment of Niemann-Pick Type C disease, a lysosomal lipid storage disorder, and is used in clinical practice. Since cholesterol accumulation and/or dysregulated cholesterol metabolism has been described in various malignancies, including leukemia, we hypothesized that HP-β-CyD itself might have anticancer effects. This study provides evidence that HP-β-CyD inhibits leukemic cell proliferation at physiologically available doses. First, we identified the potency of HP-β-CyD in vitro against various leukemic cell lines derived from acute myeloid leukemia (AML), acute lymphoblastic leukemia and chronic myeloid leukemia (CML). HP-β-CyD treatment reduced intracellular cholesterol resulting in significant leukemic cell growth inhibition through G₂/M cell-cycle arrest and apoptosis. Intraperitoneal injection of HP-β-CyD significantly improved survival in leukemia mouse models. Importantly, HP-β-CyD also showed anticancer effects against CML cells expressing a T315I BCR-ABL mutation (that confers resistance to most ABL tyrosine kinase inhibitors), and hypoxia-adapted CML cells that have characteristics of leukemic stem cells. In addition, colony forming ability of human primary AML and CML cells was inhibited by HP-β-CyD. Systemic administration of HP-β-CyD to mice had no significant adverse effects. These data suggest that HP-β-CyD is a promising anticancer agent regardless of disease or cellular characteristics.

[Results of Training for Personnel Involved in Blood-Transfusion Testing Outside of Regular Work Hours at Saga University Hospital]

Laboratory testing prior to blood transfusion outside of regular hours in many hospitals and clinics is frequently conducted by technicians without sufficient experience in such testing work. To obtain consistent test results regardless of the degree of laboratory experience with blood transfusion testing, the number of facilities introducing automated equipment for testing prior to blood transfusion is increasing. Our hospital's blood transfusion department introduced fully automated test equipment in October of 2010 for use when blood transfusions are conducted outside of regular hours. However, excessive dependence on automated testing can lead to an inability to do manual blood typing or cross-match testing when necessitated by breakdowns in the automated test equipment, in the case of abnormal specimen reactions, or other such case. In addition, even outside of normal working hours there are more than a few instances in which transfusion must take place based on urgent communications from clinical staff, with the need for prompt and flexible timing of blood transfusion test and delivery of blood products. To address this situation, in 2010 we began training after-hours laboratory personnel in blood transfusion testing to provide practice using test tubes manually and to achieve greater understanding of blood transfusion test work (especially in cases of critical blood loss). Results of the training and difficulties in its implementation for such after-hours laboratory personnel at our hospital are presented and discussed in this paper. [Original]

Abstract 5250: Analysis of circulating plasma DNA on metastatic animal model using human lung cancer cell lines

Circulating plasma DNA (cpDNA) has been widely applied to detecting molecular alterations of cancers. However, the mechanisms regarding how tumor derived DNA is released into peripheral blood have not been clarified. In this study, we established animal model with highly metastasis, and analysis relationship between the amount of cpDNA derived from tumor and tumor progression. We recently established a system for monitoring EGFR mutation, T790M using mutation-biased PCR and quenched probe (MBP-QP) method. T790M is a gatekeeper mutation of EGFR, which appears in half of lung cancer patients treated with EGFR tyrosine kinase inhibitors (EGFR-TKI). Because the system is highly sensitive, it was able to successfully detect T790M using circulating plasma DNA (cpDNA). Using this system, we performed a prospective, multicenter, observational study, and showed usefulness of this method for monitoring acquired resistance to EGFR-TKI. In this study, we applied the technique to monitor metastasis in an animal model. To establish an animal model reflecting human metastatic lung cancers, we used NOD/SCID/Jak3null (NOJ) mice, which exhibit deficiencies in NK cell activity, macrophage and dendritic cell function, and complement activation, as well as T and B cell deficiencies. After screening twenty human lung cancer cell lines through expression patterns of E-cadherin and vimentin according to epithelial mesenchymal transition features, an H1975 cell line carrying EGFR mutations, L858R and T790M, was selected for investigation. After inoculation of the cells into the dorsal flanks, metastatic status was monitored. The frequency of metastasis to axillary and abdominal lymph nodes was 79% (11/14), and that to lung and liver occurred in 64% (9/14). Peritoneal dissemination with ascites was also observed in 29% (4/14). In total, one or more of these types of metastasis was observed in 93% (13/14) of the mice. We confirmed the existence of H1975 cells in metastatic lesions by detection of T790M and L858R using MBP-QP system. Next, we investigated the relationship between tumor progression and amount of EGFR mutations with cpDNA analyzed from the area under the mutation peak. The frequency of metastasis increased with time concomitant with increasing detection of EGFR mutations using plasma DNA. Tumor volume of the primary lesion was significantly correlated with area under the mutation peak, whereas that of metastatic lesions for T790M was not. Regardless of tumor volume of metastatic lesions, area under the mutation peak was relatively high. This animal model should be useful to investigate further the mechanisms of circulating tumor derived DNA in peripheral blood and could be applicable to a preclinical trial for a novel anti-cancer agent targeted at metastasis.

Citation Format: Naoko Aragane, Akemi Sato, Naomi Kobayashi, Eisaburo Sueoka, Seiji Okada, Shinya Kimura. Analysis of circulating plasma DNA on metastatic animal model using human lung cancer cell lines. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5250. doi:10.1158/1538-7445.AM2015-5250

Abstract LB-027: Inhibition of mammalian target of rapamycin by Torin2, an ATP-competitive inhibitor, induces growth inhibition in adult T cell leukemia

Adult T cell leukemia (ATL) is one of the aggressive malignant lymphomas induced by the infection of human T-cell Lymphotropic virus-1. Advanced stages of ATL patients still have a poor prognosis and novel therapeutic approaches are needed. Since mammalian target of rapamycin (mTOR) is a key molecule in cell growth and survival in a number of hematological malignancies, we here focused on mTOR signaling pathway consisting from mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). It has been already reported that inhibition of mTOR with rapamycin, a classical mTOR inhibitor, or its derivatives induces growth inhibition in ATL cells, and we found that Torin2, a second generation ATP-competitive mTOR inhibitor, has more beneficial effects than rapamycin does. Although Torin2 showed weaker growth inhibitory effect against ATL cell lines than rapamycin did at low concentrations (&lt; 10 nM), its effect exceeded at higher concentrations (&gt; 10nM) in CCK-8 assay and Trypan blue staining assay. To understand differences of mechanism of action between Torin2 and rapamycin, we first studied apoptosis and cell cycle arrest of the ATL cell line stained with annexin-FITC; Although both Torin2 and rapamycin caused G1 cell cycle arrest, a small number of ATL cells died in apoptotic manner at higher concentration of Torin2 but not of rapamycin. It is important to note that inhibition of mTOR pathway with rapamycin induced feedback activation of Akt (phosphorylation of Akt at Ser471), down stream of mTORC2, at high concentrations (&gt; 50 nM) but Torin2 inhibited phosphorylation of Akt dose-dependently. Based on these results, we think Torin2 inhibits mTORC1 and mTORC2 followed by G1 cell cycle arrest, however rapamycin inhibits only mTORC1 and it induces feedback activation of Akt at high concentration resulting in resistance to apoptotic cell death. Thus, inhibition of mTOR pathway with Torin2 is new potent therapeutic approach in the treatment of ATL.

Citation Format: Tatsuro Watanabe, Naoko Aragane, Eisaburo Sueoka. Inhibition of mammalian target of rapamycin by Torin2, an ATP-competitive inhibitor, induces growth inhibition in adult T cell leukemia. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-027. doi:10.1158/1538-7445.AM2015-LB-027

Primary cancer prevention by green tea, and tertiary cancer prevention by the combination of green tea catechins and anticancer compounds

Green tea is a daily beverage, a non-oxidized non-fermented product containing at least four green tea catechins. Considering our first results when repeated applications of (-)-epigallocatechin gallate (EGCG) prevented tumor promotion in mouse skin, we have continued to look at green tea as a possible cancer preventive agent. 1) The 10-year prospective cohort study by Drs. K. Nakachi and K. Imai revealed that drinking 10 Japanese-size cups (120 mL/cup) of green tea per day delayed cancer onset in humans by 7.3 years among females and by 3.2 years among males. The delay of cancer onset is of course significant evidence of primary cancer prevention in humans. 2) In collaboration with Dr. H. Moriwaki’s group we successfully presented a prototype of tertiary cancer prevention showing that 10 Japanese-size cups of green tea daily, supplemented with tablets of green tea extract (G.T.E), reduced recurrence of colorectal adenomas in polypectomy patients by 51.6% (from 31% to 15%). 3) In 1999, we first reported that the combination of green tea catechins and non-steroidal anti-inflammatory drugs showed synergistic anticancer effects in both in vitro and in vivo experiments, along with elucidation of the mechanism. 4) Further studies by other investigators have revealed that various combinations of EGCG or green tea extract and anticancer compounds inhibit tumor volume in xenograft mouse models implanted with various human cancer cell lines. Green tea is a cancer preventive, and green tea catechins act as synergists with anticancer compounds.

Highlights of the Twelfth Japan-Korea Joint Symposium on Cancer and Ageing Research

INTRODUCTION

This paper reports the highlights of the presentation at the Twelfth Japan-Korea Joint Symposium on Cancer and Ageing Research was held at the auditorium of Saitama Cancer Center in Saitama, Japan, in June 19-21, 2014.

RESULTS

Thirty-two oral presentations were delivered on various themes, such as therapeutic agents, cancer stem cells, EMT signaling, molecular epidemiology, cellular senescence, and clinical research, to more than 80 participants. The significance of translational research was emphasized in clinical sessions by physicians. A special session, "Thinking about Scientific Philosophy," featured presentations by distinguished scientists from Japan and Korea.

CONCLUSION

We really feel that this meeting of minds has a unique and creative purpose, and a role of a prototype for Joint Symposia in Asian countries. The next Symposium is anticipated in 2016 in Jeju, Korea.

Synergistic enhancement of anticancer effects on numerous human cancer cell lines treated with the combination of EGCG, other green tea catechins, and anticancer compounds

PURPOSE

In 2008, we reported that 10 Japanese-size cups of green tea daily, supplemented with tablets of green tea extract (GTE), reduced the recurrence of colorectal adenoma by 51.6% in patients after polypectomy. Based on these results, we paid special attention to Japanese cancer patients, who consume green tea every day and are administered anticancer drugs. This encouraged us to study whether the combination of green tea catechins and anticancer drugs has the potential to enhance the efficacy of the drugs.

RESULTS AND DISCUSSION

The combination of GTE and NSAIDs synergistically inhibited tumor development in rodents through the activation of the GADD153-DR5-TRAIL apoptotic pathway. Since then, this study was further extended by various investigators to the combinations of EGCG and other green tea catechins with anticancer compounds, the latter of which include NSAIDs, phytochemicals, and anticancer drugs. In order to demonstrate whether diversity of the combinations would generally induce synergistic anticancer effects on numerous human cancer cell lines, we studied the results of 42 in vitro combination experiments and the synergistic inhibition of tumor volume of 13 combination experiments using xenograft mouse models, which were previously reported by other investigators. The various combinations of EGCG and anticancer compounds induced similar synergistic anticancer effects for both in vitro and in vivo experiments, and showed an average reduction in tumor volume by 70.3%. Considering the evidence showing that treatment with EGCG inhibited self-renewal of cancer stem cells, the combination shows a great advantage.

CONCLUSION

Green tea is a cancer preventive for humans, showing a new trend of green tea catechins as synergists with anticancer compounds.

Correlation between plasma DNA and tumor status in an animal model

Overcoming metastasis is one of the most important issues with lung cancer. Since metastasis arises through complex steps, a suitable animal model is indispensable for investigation of metastasis. To establish an animal model reflecting human metastatic lung cancers, we used NOD/SCID/Jak3null (NOJ) mice, which exhibit deficiencies in NK cell activity, macrophage and dendritic cell function, and complement activation, as well as T and B cell deficiencies. After screening twenty human lung cancer cell lines through expression patterns of E-cadherin and vimentin according to epithelial mesenchymal transition features, an H1975 cell line carrying EGFR mutations, L858R and T790M, was selected for investigation. Inoculation of the cells into the dorsal flanks caused systemic metastases after one month in lymph nodes, liver, lung, and peritoneum, suggesting that metastases occurred both lymphogenically and hematogenously. We confirmed the existence of H1975 cells in metastatic lesions by detection of T790M and L858R using the mutation-biased PCR and quenching probe (MBP-QP) system previously established in our laboratory. In addition, tumor-derived plasma DNA could be detected using the MBP-QP method. The amount of tumor-derived DNA was associated with tumor volume, whereas an unrelated large amount of tumor-derived DNA was circulating in the presence of metastasis. We present a novel animal model with systemic metastasis with human lung cancer cells. The amount of tumor derived DNA would be related with tumor volume and tumor progression such as metastasis.