Interrupting specific hydrogen bonds between ELF3 and MED23 as an alternative drug resistance-free strategy for HER2-overexpressing cancers.

INTRODUCTION: HER2 overexpression induces cancer aggression and frequent recurrences in many solid tumors. Because HER2 overproduction is generally followed by gene amplification, inhibition of protein-protein interaction (PPI) between transcriptional factor ELF3 and its coactivator MED23 has been considered an effective but challenging strategy. OBJECTIVES: This study aimed to determine the hotspot of ELF3-MED23 PPI and further specify the essential residues and their key interactions in the hotspot which are controllable by small molecules with significant anticancer activity. METHODS: Intensive biological evaluation methods including SEAP, fluorescence polarization, LC-MS/MS-based quantitative, biosensor, GST-pull down assays, and in silico structural analysis were performed to determine hotspot of ELF3-MED23 PPI and to elicit YK1, a novel small molecule PPI inhibitor. The effects of YK1 on possible PPIs of MED23 and the efficacy of trastuzumab were assessed using cell culture and tumor xenograft mouse models. RESULTS: ELF3-MED23 PPI was found to be specifically dependent on H-bondings between D400, H449 of MED23 and W138, I140 of ELF3 for upregulating HER2 gene transcription. Employing YK1, we confirmed that interruption on these H-bondings significantly attenuated the HER2-mediated oncogenic signaling cascades and exhibited significant in vitro and in vivo anticancer activity against HER2-overexpressing breast and gastric cancers even in their trastuzumab refractory clones. CONCLUSION: Our approach to develop specific ELF3-MED23 PPI inhibitor without interfering other PPIs of MED23 can finally lead to successful development of a drug resistance-free compound to interrogate HER2 biology in diverse conditions of cancers overexpressing HER2.

Development of Population-Based Cancer Indicators and a Measurement of Cancer Care Continuum Using a Modified Delphi Method.

To identify population-based cancer indicators and construct monitoring systems for the entire lifecycle of cancer patients using a modified Delphi method. A modified Delphi method was used to identify the cancer indicators and measurement by scoping review and gray literature. The final list of cancer indicators was developed by consensus of 11 multidisciplinary experts over multiple rounds and rating scored the importance of each indicator on a 10-point scale. Frequency analysis was performed to rate with median scores ≥7 and finalized the list of indicators according to the priority. Initially, 254 indicators were identified, of which 94 were considered important and feasible. After two rounds of rating by the experts and panel discussions, 26 indicators were finalized in six domains: primary prevention (n = 7), secondary prevention (n = 11), treatment (n = 2), quality of life (n = 4), survivor management (n = 1), and end-of-life care (n = 1). The Donabedian model used for examining health services and the Institute of Medicine quality of healthcare domains were applied to the measurement system. Panel experts identified cancer indicators based on priorities with a high level of consensus, providing a scrupulous foundation for community-based monitoring of cancer patients.

Immunogenicity and safety of a novel recombinant protective antigen anthrax vaccine (GC1109), a randomized, single-blind, placebo controlled phase II clinical study.

BACKGROUND: The demand on effective and safe anthrax vaccine is increasing as a part of the preparedness for possible bioterrorism in the future. We performed a randomized, single-blind, placebo controlled phase II clinical study to evaluate the immunogenicity and safety of a novel recombinant protective antigen (rPA) anthrax vaccine, GC1109, in healthy adult volunteers. METHODS: Participants were randomized to experiment groups (0.3 mL, 0.5 mL, and 1.0 mL of GC1109) or placebo group (normal saline 0.5 mL) in 2:2:2:1 ratio. They received respective vaccines intramuscularly at 0, 4 and 8 weeks. Immunogenicity was evaluated by seroconversion rate and geometric mean titer (GMT) of lethal toxin neutralizing assay (TNA) and anti-PA IgG by ELISA. Safety was assessed by laboratory tests, and solicited and unsolicited adverse events on diary cards. RESULTS: 30, 29, 30 participants were randomized to 0.3, 0.5, and 1.0 mL of GC1109 groups, respectively, while 15 to placebo group. 92 participants received all three doses. In per-protocol analysis, TNA GMTs at week 12 were 296.5, 285.2, and 433.2 in the three groups, respectively. Seroconversion rates measured by ELISA were 100% at week 12 in the three groups. Local and systemic vaccine-related adverse events were frequent; however, most of them were mild, and no serious events were observed. CONCLUSIONS: A new rPA anthrax vaccine GC1109 was immunogenic after three doses of intramuscular administration, and was well-tolerated.

5-Fluorouracil, mitomycin-c, and polysaccharide-k versus uracil-ftorafur and polysaccharide-K as adjuvant chemoimmunotherapy for patients with locally advanced gastric cancer with curative resection.

BACKGROUND: Despite the small but significant survival benefit of adjuvant chemotherapy in locally advanced gastric cancer (LAGC), the optimal regimen remains to be determined. We conducted a randomized trial comparing oral (PO) chemoimmunotherapy (CITX) with intravenous (IV) CITX in LAGC patients (stages IB-IIIB) with curative resection (≥ D2 dissection). METHODS: The patients were randomized to the IV (5-fluorouracil 500 mg/m(2) weekly for 24 weeks, mitomycin-C 8 mg/m(2) every 6 weeks × 4) or the PO (uracil-ftorafur (UFT) 400-600 mg/day for 12 months) group. Patients in both groups received PO polysaccharide-K (3 g/day for 4 months). The planned number of patients was 368 for proving the non-inferiority of PO CITX compared to IV CITX for overall survival. RESULTS: The trial was closed prematurely after enrolling 82 patients (44 in the IV group, 38 in the PO group). With a median follow-up of 82 months, there were no significant differences in the 5-year disease-free survival (73% vs. 55%, p = 0.358) and overall survival (77% vs. 66%, p = 0.159) between the 2 groups. The IV group demonstrated a higher incidence of grade 2 or 3 neutropenia, thrombocytopenia, and vomiting. CONCLUSIONS: PO CITX with UFT appeared to be at least non-inferior to 5-fluorouracil and mitomycin-C CITX, with lower toxicity in the adjuvant treatment for LAGC.

A Korean female patient with thiamine-responsive pyruvate dehydrogenase complex deficiency due to a novel point mutation (Y161C)in the PDHA1 gene.

Pyruvate dehydrogenase complex (PDHC) deficiency is mostly due to mutations in the X-linked E1alpha subunit gene (PDHA1). Some of the patients with PDHC deficiency showed clinical improvements with thiamine treatment. We report the results of biochemical and molecular analysis in a female patient with lactic acidemia. The PDHC activity was assayed at different concentrations of thiamine pyrophosphate (TPP). The PDHC activity showed null activity at low TPP concentration (1 x 10(-3) mM), but significantly increased at a high TPP concentration (1 mM). Sequencing analysis of PDHA1 gene of the patient revealed a substitution of cysteine for tyrosine at position 161 (Y161C). Thiamine treatment resulted in reduction of the patient's serum lactate concentration and dramatic clinical improvement. Biochemical, molecular, and clinical data suggest that this patient has a thiamine-responsive PDHC deficiency due to a novel mutation, Y161C. Therefore, to detect the thiamine responsiveness it is necessary to measure activities of PDHC not only at high but also at low concentration of TPP.

Chaperone-like activities of alpha-synuclein: alpha-synuclein assists enzyme activities of esterases.

Alpha-synuclein, a major constituent of Lewy bodies (LBs), has been implicated to play a critical role in the pathogenesis of Parkinson's disease (PD), although the physiological function of alpha-synuclein has not yet been known. Here we have shown that alpha-synuclein, which has no well-defined secondary or tertiary structure, can protect the enzyme activity of microbial esterases against stress conditions such as heat, pH, and organic solvents. In particular, the flexibility of alpha-synuclein and its C-terminal region seems to be important for complex formation, but the structural integrity of the C-terminal region may not be required for stabilization of enzyme activity. In addition, atomic force microscopy (AFM) and in vivo enzyme assays showed highly specific interactions of esterases with alpha-synuclein. Our results indicate that alpha-synuclein not only protects the enzyme activity of microbial esterases in vitro, but also can stabilize the active conformation of microbial esterases in vivo.