MicroRNA‐375‐3p enhances chemosensitivity to 5‐fluorouracil by targeting thymidylate synthase in colorectal cancer

Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU.     

Hair shaft miRNA‐221 levels as a new tumor marker of malignant melanoma

miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.     

二肽基肽酶Ⅳ抑制剂P32/98

二肽基肽酶Ⅳ(DPPⅣ)涉及2型糖尿病病理过程中的信号传导过程,其抑制剂能够增强胰岛素样多肽(GIP)和胰高血糖素样肽片段(GLP)的活性,并能提高葡萄糖耐受水平.动物实验研究表明,糖尿病模型大鼠口服DPPⅣ抑制剂P32/98,能降低DPPⅣ的活性,改善糖耐受性以及增加胰岛素的敏感性.临床试验进一步揭示,P32/98的安全性和耐受性良好,能明显改善受试者糖耐受性和胰岛素应答水平.     

Enzyme-linked Immunosorbent Assay of Pro-gastrin-releasing Peptide for Small Cell Lung Cancer Patients in Comparison with Neuron-specific Enolase Measurement

Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.     

Blood endotyping distinguishes the profile of vitiligo from that of other inflammatory and autoimmune skin diseases

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Linking DJ-1 to neurodegeneration offers novel insights for understanding the pathogenesis of Parkinson’s disease

Rare monogenic forms of Parkinson's disease (PD) are promoting our understanding of the molecular pathways involved in the common, non-Mendelian forms of the disease. Here, we focus on PARK7, an autosomal recessive form of early-onset parkinsonism caused by mutations in the DJ-1 gene. We first review the genetics of this form and the rapidly expanding knowledge about the structure and biochemical properties of the DJ-1 protein. We also discuss how DJ-1 dysfunction might lead to neurodegeneration, and the implications of this novel piece of information for the pathogenesis of the common PD forms. Although much work remains to be done to clarify the biology of DJ-1, its proposed activity as a molecular chaperone and/or as oxidative sensor appear intriguing in the light of the current theories on the pathogenesis of PD.     

CD98 regulates the phosphorylation of HER2 and a bispecific anti-HER2/CD98 antibody inhibits the growth signal of human breast cancer cells

Human epidermal growth factor receptor (HER) family proteins are currently major targets of therapeutic monoclonal antibodies against various epithelial cancers. However, the resistance of cancer cells to HER family-targeted therapies, which may be caused by cancer heterogeneity and persistent HER phosphorylation, often reduces overall therapeutic effects. We herein showed that a newly discovered molecular complex between CD98 and HER2 affected HER function and cancer cell growth. The immunoprecipitation of the HER2 or HER3 protein from lysates of SKBR3 breast cancer (BrCa) cells revealed the HER2-CD98 or HER3-CD98 complex. The knockdown of CD98 by small interfering RNAs inhibited the phosphorylation of HER2 in SKBR3 cells. A bispecific antibody (BsAb) that recognized the HER2 and CD98 proteins was constructed from a humanized anti-HER2 (SER4) IgG and an anti-CD98 (HBJ127) single chain variable fragment, and this BsAb significantly inhibited the cell growth of SKBR3 cells. Prior to the inhibition of AKT phosphorylation, BsAb inhibited the phosphorylation of HER2, however, significant inhibition of HER2 phosphorylation was not observed in anti-HER2 pertuzumab, trastuzumab, SER4 or anti-CD98 HBJ127 in SKBR3 cells. The dual targeting of HER2 and CD98 has potential as a new therapeutic strategy for BrCa.