Efficacy of EGFR Tyrosine Kinase Inhibitors in Non-small Cell Lung Cancer Patients Harboring Different Types of EGFR Mutations:A Retrospective Analysis

With the development of molecular pathology, many types of epidermal growth factor receptor（EGFR） mutations have been identified. The efficacy of EGFR tyrosine kinase inhibitors（EGFR-TKIs） in non-small cell lung cancer（NSCLC） patients with different types of EGFR mutations, especially in patients with single rare mutations or complex mutations（co-occurrence of two or more different mutations）, has not been fully understood. This study aimed to examine the efficacy of EGFR-TKIs in NSCLC patients with different types of EGFR mutations. Clinical data of 809 NSCLC patients who harbored different types of EGFR mutations and treated from January 2012 to October 2016 at Renmin Hospital and Zhongnan Hospital, Wuhan, were retrospectively reviewed. The clinical characteristics of these patients and the efficacy of EGFR-TKIs were analyzed. Among these patients, 377 patients had only the EGFR del-19 mutation, 362 patients the EGFR L858R mutation in exon 21, 33 patients single rare mutations and 37 patients complex mutations. Among these 809 patients, 239 patients were treated with EGFR-TKIs. In all the 239 patients, the disease control rate（DCR） was 93.7% with two patients（0.2%） achieving complete response（CR）, the median progression free survival（PFS） was 13.0 months（95% confidence interval [CI], 11.6–14.4 months）, and the median overall survival（OS） was 55.0 months（95% CI, 26.3–83.7 months）. Subgroup analysis revealed that the DCR in patients harboring single rare or complex mutations of EGFR was significantly lower than in those with del-19 or L858 R mutation（P〈0.001）. Patients with classic mutations（del-19 and/or L858 R mutations） demonstrated longer PFS（P〈0.001） and OS（P=0.017） than those with uncommon mutations（single rare and/or complex mutations）. Furthermore, the patients with single rare mutations had shorter median OS than in those with other mutations. Multivariate Cox regression analysis identified that the type of EGFR mutations was an independent risk factor for PFS（hazard ratio [HR]=0.308, 95% CI, 0.191–0.494, P〈0.001） and OS（HR=0.221, 95% CI, 0.101–0.480, P〈0.001）. The results suggest that the single rare or complex EGFR mutations confer inferior efficacy of EGFR-TKIs treatment to the classic mutations. The prognosis of the single rare EGFR mutations is depressing. EGFR-TKIs may be not a good choice for NSCLC patients with single rare mutations of EGFR. Further studies in these patients with uncommon mutations（especially for the patients with single rare mutations） are needed to determine a better precision treatment.

CRYSTAL STRUCTURE OF THE COMPLEX OF MUNG BEAN TRYPSIN INHIBITOR LYSINE ACTIVE FRAGMENT WITH BOVINE TRYPSIN AT 1.8 A RESOLUTION

The structure of the complex of mung bean trypsin inhibitor lysine active fragment with bovine trypsin has been determined at a resolution of 1.8 A by A-ray crystallographic analysis and the complex model refined by restrained least-squares minimization with the data between 10 and 1.8 resolution.The current conventional R factor is 17.3%,and the model con- tains 1648 protein atoms,219 inhibitor atoms and 126 water molecules.The most prominent feature of the inhibitor fragment is that it does not contain any alpha-helices.Most of the chain fold in an irregular fashion.The seven residues of the binding segment of the inhibitor lysine active frag- ment are in specific contact with bovine trypsin.The binding interaction and geometry around the reactive site are similar to that observed in other studies of trypsin-inhibitor complexes.

Metal complexes of anthranilic acid derivatives: A new class of noncompetitive α-glucosidase inhibitors

Metal complexes of anthranilic acid derivatives that constitute a novel class of non-sugar-type α- glucosidase inhibitors were synthesized and assessed in vitro for inhibitory activity. All of the AgO） complexes （9-16） inhibited α-glucosidase at the nanomolar scale, while 3,5-dichloroanthranilic acid silver（1） （9） was the most potent （ICso = 3.21 nmol/L）. Analysis of the kinetics of enzyme inhibition indicated that the mechanism of the newly prepared silver complexes was noncompetitive. The structure-activity relationships were also analyzed, and thev are discussed in this report.

Mitochondrial complex Ⅰ as a therapeutic target for Alzheimer’s disease

Alzheimer’s disease(AD),the most prominent form of dementia in the elderly,has no cure.Strategies focused on the reduction of amyloid beta or hyperphosphorylated Tau protein have largely failed in clinical trials.Novel therapeutic targets and strategies are urgently needed.Emerging data suggest that in response to environmental stress,mitochondria initiate an integrated stress response(ISR)shown to be beneficial for healthy aging and neuroprotection.Here,we review data that implicate mitochondrial electron transport complexes involved in oxidative phosphorylation as a hub for small molecule-targeted therapeutics that could induce beneficial mitochondrial ISR.Specifically,partial inhibition of mitochondrial complex I has been exploited as a novel strategy for multiple human conditions,including AD,with several small molecules being tested in clinical trials.We discuss current understanding of the molecular mechanisms involved in this counterintuitive approach.Since this strategy has also been shown to enhance health and life span,the development of safe and efficacious complex Ⅰ inhibitors could promote healthy aging,delaying the onset of age-related neurodegenerative diseases.

Mitochondrial dysfunction in Parkinson’s disease

Parkinson’s disease(PD)is the second most common neurodegenerative disease,which is characterized by loss of dopaminergic(DA)neurons in the substantia nigra pars compacta and the formation of Lewy bodies and Lewy neurites in surviving DA neurons in most cases.Although the cause of PD is still unclear,the remarkable advances have been made in understanding the possible causative mechanisms of PD pathogenesis.Numerous studies showed that dysfunction of mitochondria may play key roles in DA neuronal loss.Both genetic and environmental factors that are associated with PD contribute to mitochondrial dysfunction and PD pathogenesis.The induction of PD by neurotoxins that inhibit mitochondrial complex I provides direct evidence linking mitochondrial dysfunction to PD.Decrease of mitochondrial complex I activity is present in PD brain and in neurotoxin-or genetic factorinduced PD cellular and animal models.Moreover,PINK1 and parkin,two autosomal recessive PD gene products,have important roles in mitophagy,a cellular process to clear damaged mitochondria.PINK1 activates parkin to ubiquitinate outer mitochondrial membrane proteins to induce a selective degradation of damaged mitochondria by autophagy.In this review,we summarize the factors associated with PD and recent advances in understanding mitochondrial dysfunction in PD.