While the cell wall strictly controls cell size and morphology in bacteria, spheroplasts lack cell walls and can become enlarged in growth medium under optimal conditions. Optimal conditions depend on the bacterial species. We frequently observed extreme enlargement of spheroplasts of the radiation-resistant bacterium Deinococcus grandis in Difco Marine Broth 2216, but not in TGY broth (a commonly used growth medium for Deinococcus). Thorough investigation of media components showed that the presence of Mg or Ca promoted extreme spheroplast enlargement, synthesizing the outer membrane. Our findings strongly suggest that Mg or Ca enlarges spheroplasts, which could change the lipid composition of the spheroplast membrane.

Although advanced lipidomics technology facilitates quantitation of intracellular lipid components, little is known about the regulation of lipid metabolism in cancer cells. Here, we show that disruption of the Gdpd3 gene encoding a lysophospholipase D enzyme significantly decreased self-renewal capacity in murine chronic myelogenous leukaemia (CML) stem cells in vivo. Sophisticated lipidomics analyses revealed that Gdpd3 deficiency reduced levels of certain lysophosphatidic acids (LPAs) and lipid mediators in CML cells. Loss of Gdpd3 also activated AKT/mTORC1 signalling and cell cycle progression while suppressing Foxo3a/β-catenin interaction within CML stem cell nuclei. Strikingly, CML stem cells carrying a hypomorphic mutation of Lgr4/Gpr48, which encodes a leucine-rich repeat (LRR)-containing G-protein coupled receptor (GPCR) acting downstream of Gdpd3, displayed inadequate disease-initiating capacity in vivo. Our data showing that lysophospholipid metabolism is required for CML stem cell maintenance in vivo establish a new, biologically significant mechanism of cancer recurrence that is independent of oncogene addiction.

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We have investigated dihydropyrimidine dehydrogenase expression as a prognostic marker in breast cancer. A total of 119 women with breast cancer undergoing surgery between 1985 and 1996 were included in this study. Eighty-seven patients were treated with postoperative chemotherapy including 5-fluorouracil or 5-fluorouracil derivatives. Fifty-nine (50%) of 119 patients were determined to be immunostaining-positive for dihydropyrimidine dehydrogenase. There was no significant difference between dihydropyrimidine dehydrogenase staining and tumour size, lymph node status, clinical stage, oestrogen receptor status, histologic grade, or 5-fluorouracil administration. When evaluated in patients treated with 5-fluorouracil or 5-fluorouracil derivatives, patients with dihydropyrimidine dehydrogenase-positive tumours had a significantly (P50.05) poorer disease-free survival compared to those with dihydropyrimidine dehydrogenase-negative tumour. No conclusion can be drawn about the prognostic impact of dihydropyrimidine dehydrogenase status in patients who were not treated with 5-fluorouracil regimes due to the small number of such cases in this series. Lymph node and dihydropyrimidine dehydrogenase status were independent prognostic factors for diseasefree survival, and lymph node status for overall survival using multivariate analysis. In conclusion, dihydropyrimidine dehydrogenase is a possible prognostic factor in patients with breast cancer treated with 5-fluorouracil or 5-fluorouracil derivatives.

Background: The standard of care for unresectable, locally advanced non-small cell lung cancer (LA-NSCLC) is chemoradiotherapy (CRT) followed by durvalumab, based on the PACIFIC trial. Disease progression and pneumonitis were reported as the main reasons to preclude the initiation of durvalumab in multiple retrospective studies. However, the transition rate and the reasons for failure to proceed to consolidation therapy with durvalumab after CRT were not evaluated prospectively. Although phase II studies in Japan have shown high efficacy and tolerability of CRT with cisplatin + S-1 (SP), no prospective study using durvalumab after SP-based CRT has yet been reported. We therefore conducted a phase II study to verify the efficacy and safety of durvalumab following SP-based CRT. In this interim analysis, we report the transition rate and the reasons for its failure. Methods: In treatment-naïve LA-NSCLC, cisplatin (60 mg/m2, day 1) and S-1 (80–120 mg/body, days 1–14) were administered with two 4-week cycles with concurrent thoracic radiotherapy (60 Gy) followed by durvalumab every 2 weeks for up to 12 months. The primary endpoint was 12 month progression-free survival rate. Results: Fifty-nine patients were enrolled, of whom 86.4% (51/59) proceeded to durvalumab. All of them initiated durvalumab within 42 days after CRT [median 18 days (range: 3–38)], including 27.5% (14/51) in <14 days. Common reasons for failure to proceed to durvalumab were disease progression (2/59, 3.4%) and adverse events (6/59, 10.2%). Among the latter cases, four resumed treatment and proceeded to durvalumab within 42 days on off-protocol. The objective response rate and the disease control rate were 62.7% and 93.2%, respectively. The incidences of ⩾grade 3 pneumonitis, febrile neutropenia, and esophagitis were 0%, 8.5%, and 3.4%, respectively. Conclusion: Regarding durvalumab after CRT, this interim analysis of the SAMURAI study clarified the high transition rate, early introduction, and reasons for failure to proceed to consolidation therapy, which were not determined in the PACIFIC trial. Trial registration: Japan Registry of Clinical Trials, jRCTs031190127, registered 1 November, 2019, https://jrct.niph.go.jp/latest-detail/jRCTs031190127 .

In lung cancer, several potential mechanisms of intrinsic and acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been explored, including mesenchymal-epithelial transition factor (MET) signaling pathway activation. On the other hand, vascular endothelial growth factor (VEGF) production of EGFR-mutated lung cancer cells is stimulated by predominantly activated MET signaling pathway. Therefore, the inhibition of VEGF axis as the downstream target of MET signaling pathway seems promising. Here, for the first time, we report the potential efficacy of combination therapy with bevacizumab and erlotinib in an EGFR-mutated NSCLC patient with MET amplification who showed intrinsic resistance to initial EGFR-TKI therapy. The patient was a 60-year-old male smoker, showing performance status (PS) 2, who presented with stage IV lung adenocarcinoma (cT4N2M1a) harboring the EGFR exon 19 deletion mutation. He was started on gefitinib at 250 mg/day. However, by 28 days, his symptoms further deteriorated along with the increased tumor size, resulting in PS 3. Then, repeat biopsy was performed, showing the positive MET amplification and the preserved EGFR exon 19 deletion mutation. Therefore, on the basis of the potential efficacy for activated MET signaling pathway as well as the confirmed safety by the known phase II trial for EGFR-mutated patients, the patient was started on combination therapy with bevacizumab at 15 mg/kg every 3 weeks plus erlotinib at 150 mg/day. By 21 days, his symptoms gradually improved along with the decreased tumor size, resulting in better PS with no severe toxicities.

Background: Neutrophil-to-lymphocyte ratio (NLR) has recently attracted attention as a prognostic predictor in patients with non-small cell lung cancer (NSCLC) who receive immune checkpoint inhibitors (ICIs). However, the utility of NLR in relation to cytotoxic anticancer drugs or molecular targeted drugs remains unclear. We determined if NLR could predict the treatment efficacy and prognosis in NSCLC patients who receive cytotoxic anticancer drugs or molecular targeted drugs, as well as ICIs, in a crosssectional manner.Methods: Of 658 patients with advanced NSCLC who received first-line systemic treatment in our hospital between 2008 and 2019, 312 who met the analytical criteria were included in the study. We retrospectively analyzed the ability of NLR with a cut-off value of 5 to predict time to treatment failure (TTF) and overall survival (OS) in patients who received the following treatments: first-line treatment with molecular targeted drugs (mt group, n=100); first-line treatment with cytotoxic anticancer drugs (wt group, n=212); and firstline treatment with cytotoxic anticancer drugs followed by ICIs (ICI group, n=58).Results: In the high-and low-NLR mt subgroups, median TTFs were 6.7 and 14.9 months (P<0.01), respectively, and median survival times (MSTs) were 17.8 and 39.1 months (P<0.01), respectively. In the high-and low-NLR wt subgroups, median TTFs were 1.5 and 5.8 months (P<0.01), and MSTs were 6.3 and 20.7 months (P<0.01), respectively. In the high-and low-NLR ICI subgroups, median TTFs were 1.3 and 6.8 months (P<0.01), and MSTs were 9.2 and 25.8 months (P<0.01), respectively. Multivariate analysis identified NLR as a significant independent predictor of TTF [hazard ratio (HR) 1.89, P=0.01; HR 2.51,

Rationale: Polysorbate 80 (PS80) is an amphipathic, nonionic surfactant commonly used in pharmaceutical protein formulations and is composed of fatty acid (FA) esters of polyethoxylated sorbitan. However, commercial PS80 products contain substantial amounts of by-products. The development of simple and reliable methods for PS80 component analysis is challenging given the inherent heterogeneity. Method:We developed a comprehensive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to profile the components of PS80. Semicomprehensive LC-MS/MS analyses of 11 subspecies in three commercial PS80 products were performed to estimate the average degree of polymerization of the ethylene oxide units (Avg-n) in the molecules. Furthermore, three subspecies (polyoxyethylene sorbitan monoester, polyoxyethylene isosorbide monoester, and polyoxyethylene monoester) were analyzed to estimate the composition ratios of the seven ester-bonded FAs present in PS80. Results:The Avg-n values of five polyoxyethylene sorbitan esters (none, mono, di, tri, and tetra), three polyoxyethylene isosorbide esters (none, mono, and di), and three polyoxyethylene esters (none, mono, and di) were 26. 5-30.6, 12.1-14.6, and 11.4-15.8, respectively. These values were comparable regardless of the number of esterbonded FAs. Each product had a similar FA composition ratio regardless of the differences in the subspecies. However, the obtained C18:2 values were higher than those reported in the product certificates. Conclusion:The proposed LC-MS/MS method evaluated the overall PS80 components, revealing the possibility of underestimation of ester-bonded linoleic acid using the conventional gas chromatography-mass spectrometry method. The similarity of Avg-n values and FA compositions among subspecies suggested the high reliability of these results, indicating that the presented approach may help in the quality control of PS80 formulations.Polysorbate 80 (PS80, often referred to by its commercial name, Tween 80) is an amphipathic, nonionic surfactant commonly used in pharmaceutical protein formulations to protect proteins from denaturation, aggregation, and surface adsorption. 1-3 PS80 is composed of fatty acid (FA) esters of polyethoxylated sorbitan.Polysorbates are typically synthesized in three steps (Figure 1A): first, the chemical dehydration of sorbitol, forming sorbitol monoanhydride (sorbitan) and sorbitol dianhydride (isosorbide);