Giant lipid vesicles are topologically closed compartments bounded by semipermeable flexible shells, which isolate femto- to picoliter quantities of the aqueous core from the surrounding bulk. ...Although water equilibrates readily across vesicular walls (10–2–10–3 cm3 cm–2 s–1), the passive permeation of solutes is strongly hindered. Furthermore, because of their large volume compressibility (∼109–1010 N m–2) and area expansion (102–103 mN m–1) moduli, coupled with low bending rigidities (10–19 N m), vesicular shells bend readily but resist volume compression and tolerate only a limited area expansion (∼5%). Consequently, vesicles experiencing solute concentration gradients dissipate the available chemical energy through the osmotic movement of water, producing dramatic shape transformations driven by surface-area–volume changes and sustained by the incompressibility of water and the flexible membrane interface. Upon immersion in a hypertonic bath, an increased surface-area–volume ratio promotes large-scale morphological remodeling, reducing symmetry and stabilizing unusual shapes determined, at equilibrium, by the minimal bending-energy configurations. By contrast, when subjected to a hypotonic bath, walls of giant vesicles lose their thermal undulation, accumulate mechanical tension, and, beyond a threshold swelling, exhibit remarkable oscillatory swell–burst cycles, with the latter characterized by damped, periodic oscillations in vesicle size, membrane tension, and phase behavior. This cyclical pattern of the osmotic influx of water, pressure, membrane tension, pore formation, and solute efflux suggests quasi-homeostatic self-regulatory behavior allowing vesicular compartments produced from simple molecular components, namely, water, osmolytes, and lipids, to sense and regulate their microenvironment in a negative feedback loop.
A variety of cellular processes use liquid-liquid phase separation (LLPS) to create functional levels of organization, but the kinetic pathways by which it proceeds remain incompletely understood. ...Here in real time, we monitor the dynamics of LLPS of mixtures of segregatively phase-separating polymers inside all-synthetic, giant unilamellar vesicles. After dynamically triggering phase separation, we find that the ensuing relaxation-en route to the new equilibrium-is non-trivially modulated by a dynamic interplay between the coarsening of the evolving droplet phase and the interactive membrane boundary. The membrane boundary is preferentially wetted by one of the incipient phases, dynamically arresting the progression of coarsening and deforming the membrane. When the vesicles are composed of phase-separating mixtures of common lipids, LLPS within the vesicular interior becomes coupled to the membrane's compositional degrees of freedom, producing microphase-separated membrane textures. This coupling of bulk and surface phase-separation processes suggests a physical principle by which LLPS inside living cells might be dynamically regulated and communicated to the cellular boundaries.
The epidermal growth factor receptor (EGFR) signaling pathway is crucial for regulating tumorigenesis and cell survival and may be important in the development and progression of non-small cell lung ...cancer (NSCLC). We examined the impact of EGFR-tyrosine kinase inhibitors (TKIs) on progression-free survival (PFS) and overall survival (OS) in advanced NSCLC patients with and without EGFR mutations.
Randomized trials that compared EGFR-TKIs monotherapy or combination EGFR-TKIs-chemotherapy with chemotherapy or placebo were included. We used published hazard ratios (HRs), if available, or derived treatment estimates from other survival data. Pooled estimates of treatment efficacy of EGFR-TKIs for the EGFR mutation-positive (EGFRmut(+)) and EGFR mutation-negative (EGFRmut(-)) subgroups were calculated with the fixed-effects inverse variance weighted method. All statistical tests were two-sided.
We included 23 eligible trials (13 front-line, 7 second-line, 3 maintenance; n = 14570). EGFR mutation status was known in 31% of patients. EGFR-TKIs treatment prolonged PFS in EGFRmut(+) patients, and EGFR mutation was predictive of PFS in all settings: The front-line hazard ratio for EGFRmut(+) was 0.43 (95% confidence interval CI = 0.38 to 0.49; P < .001), and the front-line hazard ratio for EGFRmut(-) was 1.06 (95% CI = 0.94 to 1.19; P = .35; P interaction < .001). The second-line hazard ratio for EGFRmut(+) was 0.34 (95% CI = 0.20 to 0.60; P < .001), and the second-line hazard ratio for EGFRmut(-) was 1.23 (95% CI = 1.05 to 1.46; P = .01; P interaction < .001). The maintenance hazard ratio for EGFRmut(+) was 0.15 (95% CI = 0.08 to 0.27; P < .001), and the maintenance hazard ratio for EGFRmut(-) was 0.81 (95% CI = 0.68 to 0.97; P = .02; P interaction < .001). EGFR-TKIs treatment had no impact on OS for EGFRmut(+) and EGFRmut(-) patients.
EGFR-TKIs therapy statistically significantly delays disease progression in EGFRmut(+) patients but has no demonstrable impact on OS. EGFR mutation is a predictive biomarker of PFS benefit with EGFR-TKIs treatment in all settings. These findings support EGFR mutation assessment before initiation of treatment. EGFR-TKIs should be considered as front-line therapy in EGFRmut(+) advanced NSCLC patients.
The response of lipid bilayers to osmotic stress is an important part of cellular function. Recent experimental studies showed that when cell-sized giant unilamellar vesicles (GUVs) are exposed to ...hypotonic media, they respond to the osmotic assault by undergoing a cyclical sequence of swelling and bursting events, coupled to the membrane’s compositional degrees of freedom. Here, we establish a fundamental and quantitative understanding of the essential pulsatile behavior of GUVs under hypotonic conditions by advancing a comprehensive theoretical model of vesicle dynamics. The model quantitatively captures the experimentally measured swell-burst parameters for single-component GUVs, and reveals that thermal fluctuations enable rate-dependent pore nucleation, driving the dynamics of the swell-burst cycles. We further extract constitutional scaling relationships between the pulsatile dynamics and GUV properties over multiple timescales. Our findings provide a fundamental framework that has the potential to guide future investigations on the nonequilibrium dynamics of vesicles under osmotic stress.
When a dry mass of certain amphiphiles encounters water, a spectacular interfacial instability ensues: It gives rise to the formation of ensembles of fingerlike tubular protrusions called myelin ...figurestens of micrometers wide and tens to hundreds of micrometers longrepresenting a novel class of nonequilibrium higher-order self-organization. Here, we report that when phase-separating mixtures of unsaturated lipid, cholesterol, and sphingomyelin are hydrated, the resulting myelins break symmetry and couple their compositional degrees of freedom with the extended myelinic morphology: They produce complementary, interlamellar radial gradients of concentrations of cholesterol (and sphingomyelin) and unsaturated lipid, which stands in stark contrast to interlamellar, lateral phase separation in equilibrated morphologies. Furthermore, the corresponding gradients of molecule-specific chemistries (i.e., cholesterol extraction by methyl-β-cyclodextrin and GM1 binding by cholera toxin) produce unusual morphologies comprising compositionally graded vesicles and buckled tubes. We propose that kinetic differences in the information processing of hydration characteristics of individual molecules while expending energy dictate this novel behavior of lipid mixtures undergoing hydration.
HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a tumoricidal protein-lipid complex with broad effects against cancer cells of different origin. The therapeutic potential is emphasized ...by a high degree of specificity for tumor tissue. Here we review early studies of HAMLET, in collaboration with the Orrenius laboratory, and some key features of the subsequent development of the HAMLET project. The early studies focused on the apoptotic response that accompanies death in HAMLET treated tumor cells and the role of mitochondria in this process. In subsequent studies, we have identified a sequence of interactions that starts with the membrane integration of HAMLET and the activation of ion fluxes followed by HAMLET internalization, progressive inhibition of MAPK kinases and GTPases and sorting of HAMLET to different cellular compartments, including the nuclei. Therapeutic efficacy of HAMLET has been demonstrated in animal models of glioblastoma, bladder cancer and intestinal cancer. In clinical studies, HAMLET has been shown to target skin papillomas and bladder cancers. The findings identify HAMLET as a new drug candidate with promising selectivity for cancer cells and a strong therapeutic potential.
Small cell lung cancer (SCLC) accounts for approximately 13% of all lung cancer cases. Small cell lung cancer is characterized by frequent relapse, and current treatments lack tumor specificity. ...Arginine is a non‐essential amino acid for human normal cells but critical to some tumor cells that cannot synthesize arginine. Therefore, arginine deprivation has become a potential therapeutic option for selected tumors. BCT‐100 is a pegylated arginase that has documented anticancer activity in arginine auxotrophic tumors, such as melanoma, hepatocellular carcinoma, and acute myeloid leukemia. One of the resistance mechanisms to arginase treatment is overexpression of argininosuccinate synthetase (ASS1) and ornithine transcarbamylase (OTC), two important enzymes in the urea cycle. We selected 9 SCLC and 1 non‐small cell lung carcinoma cell lines to determine the growth inhibition effects of BCT‐100 and established that cell lines with low expression of ASS1 and OTC are relatively sensitive to BCT‐100 treatment. Knocking down OTC in a H841 cell line could potentiate its sensitivity to BCT‐100 treatment. Arginine concentration was sharply decreased, accompanied by apoptosis through oxidative stress as well as G1 cell cycle arrest. In addition, BCT‐100 showed an anticancer effect on H446 and H510A xenograft models by lowering arginine levels and inducing apoptosis.
BCT‐100 is one type of pegylated recombinant human arginase. BCT‐100 showed an anticancer effect against small cell lung cancer through oxidative stress, apoptosis, and cell cycle arrest.
•Tuberculosis and lung cancer can co-exist especially in endemic areas.•Previous tuberculosis is a risk factor for development of lung cancer.•Diagnosis of co-existent tuberculosis and lung cancer ...requires clinical, radiological and microbiological evidence.•Co-existent granulomatous inflammation in resected lung cancer does not necessarily indicate tuberculosis.•Treatment of tuberculosis during systemic anticancer therapy can be challenging.
Tuberculosis (TB) and lung cancer are important global health threats, each accounting for 1.6 million deaths yearly. The incidence of both conditions remains high in many developing countries, especially in East Asia. There is now epidemiologic evidence that pre-existing TB poses an increased lung cancer risk. The clinical diagnosis of co-existent TB and lung cancer relies on symptoms of infection, typical radiological features and microbiological confirmation, and remains a challenge in both early and late stage lung cancer. The presence of histological granulomatous inflammation in resected lung specimens is not exclusively indicative of TB. The widely accepted systemic chemotherapy and immunotherapy for treating lung cancer are highly relevant to the occurrence of TB and its management. This review addresses the clinical approach to the diagnosis and treatment of TB that co-exists with lung cancer.
The phase III randomized PROFILE 1014 study demonstrated superiority of crizotinib to first-line chemotherapy in prolonging progression-free survival (PFS) in previously untreated patients with ALK ...receptor tyrosine kinase gene (ALK)-positive advanced nonsquamous NSCLC. This result was consistent with that in the smaller subset of East Asian patients in PROFILE 1014. The subsequent study reported here prospectively evaluated crizotinib in a larger East Asian patient population.
In this open-label phase III study (PROFILE 1029), patients were randomized 1:1 to receive orally administered crizotinib 250 mg twice daily continuously (3-week cycles) or intravenously administered chemotherapy (pemetrexed 500 mg/m2, plus cisplatin 75 mg/m2, or carboplatin at a dose to produce area under the concentration–time curve of 5–6 mg·min/mL) every 3 weeks for a maximum of six cycles. PFS confirmed by independent radiology review was the primary end point.
Crizotinib significantly prolonged PFS (hazard ratio, 0.402; 95% confidence interval CI: 0.286–0.565; p < 0.001). The median PFS was 11.1 months with crizotinib and 6.8 months with chemotherapy. The objective response rate was 87.5% (95% CI: 79.6–93.2%) with crizotinib versus 45.6% (95% CI: 35.8–55.7%) with chemotherapy (p < 0.001). The most common adverse events were increased transaminase levels, diarrhea, and vision disorders with crizotinib and leukopenia, neutropenia, and anemia with chemotherapy. Significantly greater improvements from baseline in patient-reported outcomes were seen in crizotinib-treated versus chemotherapy-treated patients.
First-line crizotinib significantly improved PFS, objective response rate, and patient-reported outcomes compared with standard platinum-based chemotherapy in East Asian patients with ALK-positive advanced NSCLC, which is similar to the results from PROFILE 1014. The safety profiles of crizotinib and chemotherapy were consistent with those previously published.
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