Synthesis, activity, and their relationships of 2,4-diaminonicotinamide derivatives as EGFR inhibitors targeting C797S mutation.

The C797S mutation is one of the major factors behind resistance to the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. Herein, we describe the discovery of the 2,4-diaminonicotinamide derivative 5j, which shows potent inhibitory activity against EGFR del19/T790M/C797S and L858R/T790M/C797S. We also report the structure-activity relationship of the 2,4-diaminonicotinamide derivatives and the co-crystal structure of 5j and EGFR del19/T790M/C797S.

Discovery of a potent, selective, and orally available EGFR C797S mutant inhibitor (DS06652923) with in vivo antitumor activity.

The C797S mutation is one of the major factors behind resistance to the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). Herein, we describe the discovery of DS06652923, a novel, potent, and orally available EGFR-triple-mutant inhibitor. Through scaffold hopping from the previously reported nicotinamide derivative, a novel biaryl scaffold was obtained. The potency was successfully enhanced by the introduction of basic substituents based on analysis of the docking study results. In addition, the difluoromethoxy group on the pyrazole ring improved the kinase selectivity by inducing steric clash with the other kinases. The most optimized compound, DS06652923, achieved tumor regression in the Ba/F3 allograft model upon its oral administration.

Detection of episodic nocturnal hypercapnia in patients with neurodegenerative disorders.

PURPOSE: Episodic nocturnal hypercapnia (eNH) in transcutaneous carbon dioxide pressure (PtcCO2) corresponding to rapid eye movement sleep hypoventilation is a useful biomarker for detecting nocturnal hypoventilation. However, the relationship between eNH and neurodegenerative diseases with sleep-related breathing disorders (SRBDs) is unknown. The aim of this study was to evaluate the relationship between eNH and nocturnal hypoventilation in neurodegenerative diseases. METHODS: Patients with neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), multiple system atrophy (MSA), Parkinson's disease, progressive supranuclear palsy, corticobasal syndrome, and idiopathic normal pressure hydrocephalus, were enrolled and received overnight PtcCO2 monitoring. The patients were divided into groups for eNH and sleep-associated hypoventilation (SH) prevalence analysis: A (ALS), B (MSA), and C (others). RESULTS: Among 110 patients, twenty-three (21%) and 10 (9%) of the patients met eNH and SH criteria, respectively. eNH and SH were significantly more frequent in groups A and B than in C. The prevalence of SH in the patients with eNH was 39% whereas most of patients with SH (90%) presented with eNH. Among patients with daytime carbon dioxide pressure in arterial blood ≤ 45 mmHg, eNH frequency was 13%, whereas none of the patients met SH criteria. The frequency of noninvasive positive pressure ventilation after PtcCO2 monitoring was significantly higher in those with than without eNH. CONCLUSIONS: eNH is common in patients with MSA and ALS who present with SRBD. eNH with overnight PtcCO2 monitoring is a useful biomarker to detect hypoventilation among neurodegenerative diseases with different SRBD mechanisms.

Discovery of EP300/CBP histone acetyltransferase inhibitors through scaffold hopping of 1,4-oxazepane ring.

EP300 and its paralog CBP play an important role in post-translational modification as histone acetyltransferases (HATs). EP300/CBP inhibition has been gaining attention as an anticancer treatment target in recent years. Herein, we describe the identification of a novel, highly selective EP300/CBP inhibitor, compound 11 (DS17701585), by scaffold hopping and structure-based optimization of a high-throughput screening hit 1. Compound 11 (DS17701585) shows dose-dependent inhibition of SRY-box transcription factor 2 (SOX2) mRNA expression in a human lung squamous cell carcinoma cell line LK2-xenografted mouse model.

The association between nutritional intake one week after admission and outcome in acute ischemic stroke patients.

OBJECTIVES: Although associations between malnutrition status at stroke admission and poor stroke outcomes have been established, the effect of nutritional intake during the acute phase remains unclear. We aimed to evaluate the associations between nutritional intake one week after admission and the outcome at three months among acute ischemic stroke (AIS) patients. MATERIALS AND METHODS: Consecutive AIS patients were investigated. Nutritional status at admission was evaluated using the Controlling Nutritional Status score, calculated from the serum albumin, lymphocyte count, and total cholesterol. We retrospectively evaluated nutritional intake (energy and protein) one week after admission, and the cutoff value of each nutritional intake level for good outcome was defined as the modified Rankin Scale 0-2 at three months after stroke onset using the receiver operating characteristic curve. RESULTS: Of the 205 patients, 146 patients had good outcomes. Mild initial neurological symptoms and good nutritional status at admission were associated with good outcome. The cutoff value of good outcome for protein intake was 0.812 g/kg/day (sensitivity: 0.884, specificity: 0.509) and that for energy intake was 19.0 kcal/kg/day (sensitivity: 0.918, specificity: 0.424). Those nutritional intake indicators were independently associated with good outcome after adjusting for baseline confounders, including stroke severity and nutritional status at admission (protein intake: odds ratio (OR), 4.04; 95% confidence intervals (CIs), 1.14-13.1, and energy intake: OR, 5.00; 95% CIs, 1.41-17.8, respectively). CONCLUSIONS: Adequate nutritional intake at one week after admission was independently associated with good outcome regardless of the nutritional status at admission or stroke severity.

4-Pyridone-3-carboxylic acid as a benzoic acid bioisostere: Design, synthesis, and evaluation of EP300/CBP histone acetyltransferase inhibitors.

Histone acetyltransferases (HATs) play a crucial role in post-translational modification. Among them, overexpression, mutation, or hyperfunction of EP300/CBP has been associated with various cancers. In this study, we identified the novel compound 2-chloro-5-[5-[(E)-[1-(3-chlorophenyl)-3-methyl-5-oxo-pyrazol-4-ylidene]methyl]-2-furyl]benzoic acid (1) as an EP300 HAT inhibitor via virtual screening. Further research has been focused on the design, synthesis, and in vitro biological evaluation of virtual hit derivatives. The studies revealed that 4-pyridone-3-carboxylic acid derivatives exhibited bioisosterism of benzoic acid. Replacement proved effective, providing compounds with similar EP300 HAT-inhibitory activity and improved cell growth-inhibitory activity compared to the benzoic acid analogs. Through these studies, we identified a potent and selective EP300/CBP HAT inhibitor.

Explosive lithium production in the classical nova V339 Del (Nova Delphini 2013).

The origin of lithium (Li) and its production process have long been uncertain. Li could be produced by Big Bang nucleosynthesis, interactions of energetic cosmic rays with interstellar matter, evolved low-mass stars, novae, and supernova explosions. Chemical evolution models and observed stellar Li abundances suggest that at least half the Li may have been produced in red giants, asymptotic giant branch (AGB) stars, and novae. No direct evidence, however, for the supply of Li from evolved stellar objects to the Galactic medium has hitherto been found. Here we report the detection of highly blue-shifted resonance lines of the singly ionized radioactive isotope of beryllium, (7)Be, in the near-ultraviolet spectra of the classical nova V339 Del (Nova Delphini 2013) 38 to 48 days after the explosion. (7)Be decays to form (7)Li within a short time (half-life of 53.22 days). The (7)Be was created during the nova explosion via the alpha-capture reaction (3)He(α,γ)(7)Be (ref. 5). This result supports the theoretical prediction that a significant amount of (7)Li is produced in classical nova explosions.

Cardiology consultation in oncology practice: a 5-year survey.

OBJECTIVE: Onco-cardiology services are expanding rapidly in Japan. To provide a better service, it is important to consider the needs of oncologists. However, little is known regarding specific needs for which oncologists should consult cardiologists to manage cardiovascular problems of their patients. We analysed cardiology consultations sought by oncologists to evaluate the role of cardiologists in cancer treatment. METHOD: We retrospectively investigated consecutive 2064 cardiology consultations of cancer patients in the University of Tsukuba Hospital, Tsukuba, Japan, between January 2014 and December 2018. RESULTS: The most common timing of cardiology consultation was before the commencement of cancer treatment (n = 1355; 65.7%), followed by after the commencement of cancer treatment (n = 686; 33.2%). Among the 361 consultations before the administration of anticancer drugs, 235 (65.1%) were for anthracycline-based regimens. There were 506 (24.5%) consultations for the management of cardiovascular emergencies developing after the commencement of cancer treatment; venous thromboembolism was the most frequent (n = 125; 24.7%), followed by atrial fibrillation (n = 110; 21.7%) and heart failure (n = 74; 14.6%). There were marked differences in the types of cardiovascular emergencies depending on the type of cancer. CONCLUSIONS: This survey revealed the various cardiovascular problems for which oncologists sought interventions by cardiologists. A multidisciplinary approach in an onco-cardiology service is essential to achieve optimal long-term outcomes.

Antimicrobial susceptibility surveillance of bacterial isolates recovered in Japan from odontogenic infections in 2013.

We report on the findings of the first antimicrobial susceptibility surveillance study in Japan of isolates recovered from odontogenic infections. Of the 38 facilities where patients representing the 4 groups of odontogenic infections were seen, 102 samples were collected from cases of periodontitis (group 1), 6 samples from pericoronitis (group 2), 84 samples from jaw inflammation (group 3) and 54 samples from phlegmon of the jaw bone area (group 4) for a total of 246 samples. The positivity rates of bacterial growth on culture were 85.3%, 100%, 84% and 88.9%, respectively, for groups 1, 2, 3 and 4. Streptococcus spp. isolation rates according to odontogenic infection group were 22% (group 1), 17.7% (group 3) and 20.7% (group 4). Anaerobic isolation rates were 66.9% (group 1), 71.8% (group 3) and 68.2% (group 4). Drug susceptibility tests were performed on 726 strains excluding 121 strains that were undergrown. The breakdown of the strains subjected to testing was 186 Streptococcus spp., 179 anaerobic gram-positive cocci, 246 Prevotella spp., 27 Porphyromonas spp., and 88 Fusobacterium spp. The isolates were tested against 30 antimicrobial agents. Sensitivities to penicillins and cephems were good except for Prevotella spp. The low sensitivities of Prevotella spp is due to ß-lactamase production. Prevotella strains resistant to macrolides, quinolones, and clindamycin were found. No strains resistant to carbapenems or penems were found among all strains tested. No anaerobic bacterial strain was resistant to metronidazole. Antimicrobial susceptibility testing performed on the S. anginosus group and anaerobic bacteria, which are the major pathogens associated with odontogenic infections, showed low MIC90 values to the penicillins which are the first-line antimicrobial agents for odontogenic infections; however, for Prevotella spp., penicillins combined with ß-lactamase inhibitor showed low MIC90 values.

A Multicenter Retrospective Study of Elective Neck Dissection for T1-2N0M0 Tongue Squamous Cell Carcinoma: Analysis Using Propensity Score-Matching.

BACKGROUND: This multicenter retrospective study aimed to determine whether elective neck dissection (END) can be performed for T1-2N0M0 tongue cancer. METHODS: Patients with T1-2N0M0 tongue squamous cell carcinoma who received treatment between January 2000 and December 2012 were enrolled at 14 multicenter study sites. The 5-year overall survival (OS) and 5-year disease-specific survival (DSS) were compared between the propensity score-matched END and observation (OBS) groups. RESULTS: The results showed that the OS rates among the 1234 enrolled patients were 85.5% in the END group and 90.2% in the OBS group (P = 0.182). The DSS rates were 87.0% in the END group and 94.3% in the OBS group (P = 0.003). Among the matched patients, the OS rates were 87.1% in the END group and 76.2% in the OBS group (P = 0.0051), and the respective DSS rates were 89.2% and 82.2% (P = 0.0335). CONCLUSION: This study showed that END is beneficial for T1-2N0M0 tongue cancer. However, END should be performed for patients with a tumor depth of 4-5 mm or more, which is the depth associated with a high rate of lymph node metastasis. The use of END should be carefully considered for both elderly and young patients.

Antithrombotic Therapy Strategy for Cancer-Associated Ischemic Stroke: A Case Series of 26 Patients.

BACKGROUND: The risk of complications from thromboembolism is increased for patients with malignancy. Cancer-associated stroke is also a serious issue with regard to the management of patients with cancer because stroke incidence often causes disabilities that affect daily life and cancer treatment strategy. METHODS: Between March 2011 and September 2017, 328 patients with acute ischemic stroke were registered to our hospital. RESULTS: Of these patients, 26 (7.9%) had a cancer-associated stroke diagnosis, namely, Trousseau syndrome. After ischemic stroke onset, malignancy treatment was changed to palliative treatment for 11 patients. Eighteen patients died 1 year after ischemic stroke onset, and 15 of these patients underwent cancer treatment according to the best supportive care policy. Of those who died, 8 underwent anticoagulation therapy. We described the clinical courses of 3 cases among 26 cases with Trousseau syndrome. Two cases took direct oral anticoagulants (DOACs) due to cancer-associated venous thromboembolism before stroke onset, and there has been no stroke recurrence with subcutaneous unfractionated heparin. In the third case, when cancer activity was suppressed, we changed DOACs from subcutaneous unfractionated heparin and continued DOACs without thromboembolic events. CONCLUSIONS: There is insufficient evidence regarding cases for which DOACs would be suitable for the prevention of thromboembolism and regarding its long-term efficacy and safety in patients with cancer. As it stands, heparin treatment, which has multifaceted antithrombotic actions, may be suitable for cancer-associated stroke prevention.

[Clinical Study to Determine the Dose Intensity of BEP Chemotherapy for Ovarian Malignant Germ Cell Tumors].

A standard regimen for ovarian malignant germ cell tumors is bleomycin, etoposide, cisplatin(BEP)chemotherapy. Adherence to a treatment schedule of every 21 days has been reported to be important. However, the incidence of febrile neutropenia( FN)and the optimaluse of granulocyte-colony stimulating factor(G-CSF)are unclear because of the low incidence of ovarian malignant germ cell tumors. We experienced 2 cases of ovarian malignant germ cell tumors that received BEP therapy after fertility-conserving surgery. In 1 case, we delayed drug administration in the first cycle because of FN. However, in order to maintain dose intensity(DI), we performed chemotherapy every 21 days by shortening the rest period. Myelosuppression may be severe in the first cycle of BEP therapy; however, it may be possible to adhere to the treatment schedule by using primary prophylactic administration of G-CSF.

Bystander killing effect of DS-8201a, a novel anti-human epidermal growth factor receptor 2 antibody-drug conjugate, in tumors with human epidermal growth factor receptor 2 heterogeneity.

Antibody-drug conjugates deliver anticancer agents selectively and efficiently to tumor tissue and have significant antitumor efficacy with a wide therapeutic window. DS-8201a is a human epidermal growth factor receptor 2 (HER2)-targeting antibody-drug conjugate prepared using a novel linker-payload system with a potent topoisomerase I inhibitor, exatecan derivative (DX-8951 derivative, DXd). It was effective against trastuzumab emtansine (T-DM1)-insensitive patient-derived xenograft models with both high and low HER2 expression. In this study, the bystander killing effect of DS-8201a was evaluated and compared with that of T-DM1. We confirmed that the payload of DS-8201a, DXd (1), was highly membrane-permeable whereas that of T-DM1, Lys-SMCC-DM1, had a low level of permeability. Under a coculture condition of HER2-positive KPL-4 cells and negative MDA-MB-468 cells in vitro, DS-8201a killed both cells, whereas T-DM1 and an antibody-drug conjugate with a low permeable payload, anti-HER2-DXd (2), did not. In vivo evaluation was carried out using mice inoculated with a mixture of HER2-positive NCI-N87 cells and HER2-negative MDA-MB-468-Luc cells by using an in vivo imaging system. In vivo, DS-8201a reduced the luciferase signal of the mice, indicating suppression of the MDA-MB-468-Luc population; however, T-DM1 and anti-HER2-DXd (2) did not. Furthermore, it was confirmed that DS-8201a was not effective against MDA-MB-468-Luc tumors inoculated at the opposite side of the NCI-N87 tumor, suggesting that the bystander killing effect of DS-8201a is observed only in cells neighboring HER2-positive cells, indicating low concern in terms of systemic toxicity. These results indicated that DS-8201a has a potent bystander effect due to a highly membrane-permeable payload and is beneficial in treating tumors with HER2 heterogeneity that are unresponsive to T-DM1.

Novel antibody drug conjugates containing exatecan derivative-based cytotoxic payloads.

Trastuzumab conjugates consisting of exatecan derivatives were prepared and their biological activities and physicochemical properties were evaluated. The ADCs showed strong efficacy and a low aggregation rate. The exatecan derivatives were covalently connected via a peptidyl spacer (Gly-Gly-Phe-Gly), which is assumed to be stable in circulation, and were cleaved by lysosomal enzymes following ADC internalization into tumor tissue. These anti-HER2 ADCs exhibited a high potency, specifically against HER2-positive cancer cell lines in vitro. The ADCs, bearing exatecan derivatives which have more than two methylene chains, exhibited superior cytotoxicity. It was speculated that steric hindrance of the cleavable amide moiety could be involved in the drug release. The adequate alkyl lengths of exatecan derivatives (13, 14, 15) were from two to four in terms of aggregation rate. The ADC having a hydrophilic moiety showed good efficacy in a HER2-positive and Trastuzumab-resistant breast carcinoma cell model in mice.

Prevalences of Peripheral Arterial Disease Diagnosed by Computed Tomography Angiography in Patients with Acute Ischemic Stroke.

BACKGROUND: Few studies have examined the prevalence of peripheral arterial disease (PAD) with the use of computed tomography angiography (CTA) in patients with acute ischemic stroke (AIS), although several reports have examined its prevalence using an ankle brachial index (ABI). We aimed to determine the prevalence of PAD indicated by CTA in patients with AIS and to clarify the prevalence of PAD in each clinical ischemic stroke subtype. METHODS: We included 199 consecutive patients with AIS admitted to our hospital and divided them into PAD and non-PAD groups according to the CTA findings. RESULTS: Of the 199 patients, 40 (20.1%) had PAD; 27 (67.5%) of the PAD patients were asymptomatic. The prevalence of abnormal ABI (≤.9) was 12.2%. Patients with PAD were older (78.3 ± 10.2 versus 71.5 ± 10.9, P <.001) and had a significantly lower ABI value (.89 ± .24 versus 1.15 ± .09, P <.001) and higher prevalence of diabetes mellitus (50.0% versus 31.4%, P = .028), atrial fibrillation (40.0% versus 16.4%, P = .001), coronary artery disease (32.5% versus 8.2%, P <.001), and intracranial arterial stenosis (47.5% versus 28.9%, P = .025) than patients without PAD. The prevalence of cerebral microbleeds was not different between patients with PAD and those without PAD (25.6% versus 25.4%, P = .985). The prevalence of PAD among ischemic stroke subtypes was highest in patients with cardioembolic infarction (40.5%). CONCLUSIONS: Almost one fourth of the AIS patients examined had PAD on CTA. Cardioembolic infarction patients showed the highest prevalence of PAD among the clinical ischemic subtypes, suggesting the coexistence of atheromatous diseases and atrial fibrillation.

Warfarin-Resistant Deep Vein Thrombosis during the Treatment of Acute Ischemic Stroke in Lung Adenocarcinoma.

CASE REPORT: A 66-year-old man with acute ischemic stroke in the setting of lung adenocarcinoma developed acute-onset deep vein thrombosis (DVT) of the lower limbs after changing to warfarin from a heparin combination. The diagnosis of warfarin-resistant DVT was established based on the laboratory data and clinical evaluation. Heparin administration resulted in good control of thrombin regulation. Cancer patients are at high risk of venous thromboembolism, and the combination of these 2 conditions is known as Trousseau's syndrome. CONCLUSION: Our report suggests that heparin administration may provide good control of thromboembolic events, although there is no established medical treatment to extend the survival of patients with Trousseau's syndrome.

Discovery of DS-5272 as a promising candidate: A potent and orally active p53-MDM2 interaction inhibitor.

We have published p53-MDM2 interaction inhibitors possessing a novel dihydroimidazothiazole scaffold. Although our lead compound 1 showed strong antitumor activity with single oral administration on a xenograft model using MV4-11 cells harboring wild-type p53, it needed a higher dose (200mg/kg) for distinct efficacy. We executed further optimization with the aim of improvement of potency and physicochemical properties. Thus optimal compounds were furnished by introducing fluorine moieties onto the phenyl ring at the C-6 position and the pyrrolidine part at the C-2 substituent; and modifying the terminal piperazine to 4,7-diazaspiro[2,5]octane variants. Furthermore, replacing 4-chlorophenyl on the C-5 position with pyridyl variant decreased nonspecific cytotoxicity significantly. Our exploration afforded DS-5272 indicating excellent antitumor efficacy from a dose of 25mg/kg on SJSA-1 xenografted models with high safety and good PK profiles, which has appropriate potency as a clinical candidate.

Diagnostic value of lower extremity ultrasonographic nerve enlargement for differentiating demyelinating Charcot-Marie-Tooth disease from chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: We previously reported that nerve enlargement assessment by nerve ultrasonography of the intermediate upper limb is applicable for distinguishing demyelinating Charcot-Marie-Tooth disease (CMT) from chronic inflammatory demyelinating polyneuropathy (CIDP). However, differences in the severity and distribution patterns of lower extremity nerve enlargement have not been established for either disease. Therefore, we examined the utility of lower extremity nerve ultrasonography for differentiating between CMT and CIDP. METHODS: Twelve patients with demyelinating CMT and 17 patients with CIDP were evaluated. The median, ulnar, tibial, and fibular nerves were evaluated in three regions: the distal upper extremity, intermediate upper extremity, and lower extremity. Of the 14 selected screening sites, the number of sites that exhibited nerve enlargement (enlargement site number, ESN) in each region was determined. RESULTS: The screening ESNs in the intermediate region and lower extremities were greater in patients with demyelinating CMT than in patients with CIDP and greater than the ESN in the distal region (p = 0.010, p = 0.001, and p = 0.101, respectively). The ESNs in the intermediate region and lower extremities significantly differed among patients with typical CIDP, CIDP variants, and demyelinating CMT (p = 0.084 and p < 0.001). Among the 14 selected screening sites, the combined upper and lower extremity ESNs exhibited the highest AUC (0.92; p < 0.001). CONCLUSIONS: Combining the upper and lower extremities for ultrasonographic nerve measurement more accurately distinguishes CIDP from demyelinating CMT.

Metastatic Maxillary Gingival Angiosarcoma with Aggressive Growth: A Case Report.

Angiosarcoma is a rare malignant tumor of endothelial origin. It is an aggressive neoplasm with early metastasis and poor prognosis and accounts for approximately 2% of all soft tissue sarcomas. Primary tumors arising in the oral cavity account for only 1% of all angiosarcomas. Here, we report a rare case of metastatic angiosarcoma of the gingiva originating from a primary mediastinal lesion. The patient was an 83-year-old man who presented with a maxillary interincisor tumor; it was a painless mass with rounded superficial necrosis measuring 23 mm× 17 mm on the labial side and 20 mm× 17 mm on the palatal side. The histopathological diagnosis was of an epithelioid angiosarcoma. Imaging revealed lesions in the mediastinum, lungs, liver, and skin. The primary lesion was considered a mediastinal lesion. As the tumor had spread throughout the body, palliative therapy was administered. However, the patient's general condition deteriorated rapidly, and he died 3 weeks after the first visit. Identifying oral metastatic malignancies may result in detection of malignant tumors at other sites; thus, oral and maxillofacial surgeons must maintain a heightened awareness of angiosarcoma.

Lead optimization of novel p53-MDM2 interaction inhibitors possessing dihydroimidazothiazole scaffold.

With the aim of discovering potent inhibitors of the p53-MDM2 interaction and thus obtaining a potent anticancer drug, we have pursued synthesis and optimization of dihydroimidazothiazole derivatives, which have been discovered via scaffold hopping by mimicing the mode of interaction between MDM2 and Nutlins. Upon the discovery we encountered a problem involving the chemical instability of the scaffold, that is, susceptibility to oxidation which led to imidazothiazole. In order to solve this problem and to obtain further potent compounds, we executed medicinal research and thus furnished the optimal compounds by incorporating the methyl group onto the C-6 position to avoid the oxidation, and by modifying the C-2 moiety of the additional proline motif, which furnished high potency. The incorporation of the pyrrolidine moiety at the C-2 position raised another hydrophobic interaction site with MDM2 protein, which was generated by the induced-fitting observed by co-crystal structure analysis. These optimal molecules showed significant improvement in potency when compared with the early lead (+)-1 or Nutlin-3a.