CRACM1 (Orai1) constitutes the pore subunit of CRAC channels that are crucial for many physiological processes 1-6 . A point mutation in CRACM1 has been associated with SCID disease in humans 2 . We have generated CRACM1 deficient mice using gene trap, where β-galactosidase (LacZ) activity identifies CRACM1 expression in tissues. We show here that the homozygous CRACM1 deficient mice are considerably smaller in size and are grossly defective in mast cell degranulation and cytokine secretion. FcεRI-mediated in vivo allergic reactions were also inhibited in CRACM1-/-mice. Other tissues expressing truncated CRACM1-LacZ fusion protein include skeletal muscles, kidney and regions in the brain and heart. Surprisingly, no CRACM1 expression was seen in the lymphoid regions of thymus. Accordingly, we found no defect in T cell development. Thus, our data reveal novel crucial roles for CRAC channels including a putative role in excitable cells.

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The progression of localized breast cancer to distant metastasis results in a poor prognosis and a high mortality rate. In this study, the contributions of miRNAs to tumor progression and the regulatory mechanisms leading to their expression alterations were investigated. Using highly lung-metastatic sub-lines from parental breast cancer cells, miRNA expression profiling revealed that the miR-17-92 cluster is significantly downregulated and the miR-18a-5p is the most evidently decreased. Ectopic expression and inhibition of miR-18a-5p demonstrated its capacity in suppressing migration and invasion of breast cancer cells. Further research identified sterol regulatory element binding transcription protein 1 (SREBP1), the master transcription factor that controls lipid metabolism, as a candidate target of miR-18a-5p. SREBP1 is overexpressed and strongly associated with worse clinical outcomes in breast cancer. Functionally SREBP1 promotes growth and metastasis of breast cancer both in vitro and in vivo. To unravel the underlying mechanism of SREBP1-mediated metastasis, mRNA profiling and subsequent gene set enrichment analyses (GSEA) were performed and SREBP1 was demonstrated to be significantly associated with epithelial-mesenchymal transition (EMT). Furthermore, SREBP1-mediated repression of E-cadherin was found to be deacetylation dependent and was augmented by recruiting Snail/HDAC1/2 repressor complex. In the light of these data, we propose that reduced expression of miR-18a-5p and concomitant overexpression of SREBP1 lead to induction of EMT states that in turn, promote breast cancer progression and metastasis. Taken together, our study reveals the crucial role of miR-18a-5p and SREBP1 in the EMT and metastasis, thus providing promising drug targets for tailored therapy in the advanced breast cancer setting.

Muscle atrophy in catabolic illnesses is due largely to accelerated protein degradation. Unfortunately, methods for detecting accelerated muscle proteolysis are cumbersome. The goal of this study was to develop a method for detecting muscle protein breakdown and assess the effectiveness of anticatabolic therapy. In rodent models of catabolic conditions, it was found that accelerated muscle protein degradation is triggered by activation of caspase-3. Caspase-3 cleaves actomyosin/myofibrils to form substrates for the ubiquitin-proteasome system and leaves a characteristic 14-kD actin fragment in the insoluble fraction of a muscle lysate. Muscle biopsies were obtained from normal adults and three groups of patients: 14 who were undergoing hip arthroplasty, 28 hemodialysis patients who were participating in exercise programs, and seven severely burned patients. In muscle of patients who were undergoing hip arthroplasty, the 14-kD actin fragment level was correlated (r ‫؍‬ 0.787, P < 0.01) with the fractional rate of protein degradation. In muscle of hemodialysis patients who were undergoing endurance exercise training, the 14-kD actin fragment decreased to values similar to levels in normal adults; strength training did not significantly decrease the actin fragment. Severely burned patients had increased muscle protein degradation and actin fragment levels, but the two measures were not significantly correlated. The experimental results suggest that the 14-kD actin fragment in muscle biopsies is increased in catabolic states and could be used in conjunction with other methods to detect and monitor changes in muscle proteolysis that occur in patients with mild or sustained increases in muscle proteolysis.

A total of 171 Streptococcus pneumoniae isolates causing invasive disease were isolated from Chinese children. The serotype distribution and antimicrobial resistance were tested. The results suggested that the 7-valent pneumococcal conjugate vaccine has a preventive effect among children and that there should be long-term surveillance for serotype 19A.

Trastuzumab is a standard treatment for HER2-positive (HER2+) breast cancer, but some patients are refractory to the therapy. MicroRNAs (miRNAs) have been used to predict therapeutic effects for various cancers, but whether miRNAs can serve as biomarkers for HER2+ metastatic breast cancer (MBC) patients remains unclear. Using miRNA microarray, we identify 13 differentially expressed miRNAs in the serum of HER2+ MBC patients with distinct response to trastuzumab, and four miRNAs are selected to construct a signature to predict survival using LASSO model. Further, our data show that miR-940 is mainly released from the tumor cells and miR-451a, miR-16-5p and miR-17-3p are mainly from the immune cells. All these four miRNAs directly target signaling molecules that play crucial roles in regulating trastuzumab resistance. In summary, we develop a serum-based miRNA signature that potentially predicts the therapeutic benefit of trastuzumab for HER2+ MBC patients and warrants future validation in prospective clinical trials.

The GDP dissociation inhibitors (GDIs) are pivotal regulators of Rho GTPases, which are essential for tumor progression, particularly in the area of metastasis. One member of GDIs was identified as RhoGDI (Rho GDP-dissociation inhibitor alpha, or RhoGDIalpha), but little is known about this protein in tumors. In this study, we used comparative proteomic analysis to show that RhoGDI is markedly up-regulated in metastatic colorectal cancer (CRC). The elevated level of RhoGDI protein in metastatic CRC was confirmed by Western blot at the tissue ( n = 24) and cell ( n = 6) levels. Further, we analyzed RhoGDI protein expression in 126 clinicopathologically characterized CRC cases by immunohistochemistry. Statistical analysis showed that there were significant differences of RhoGDI overexpression in patients categorized according to tumor invasion ( p = 0.018), lymph node metastasis ( p = 0.001) and clinical stage ( p = 0.009). A trend was also identified between high expression of RhoGDI and shorter overall survival ( p = 0.013). In the present work, we also analyzed the effect of RhoGDI on CRC cell line. Gene transfection-mediated overexpression of RhoGDI in HT29 cells, containing a low detectable level of endogenous RhoGDI, resulted in a significant increase in cell proliferation and motility in vitro. These data suggest that RhoGDI may promote CRC progression and metastasis by stimulating tumor cell growth and migration.

Recurrent pregnancy loss (RPL) is a common fertility problem that affects 1%-2% of couples all over the world. Despite exciting discoveries regarding the important roles of the decidual natural killer cell (dNK) and regulatory T cell in pregnancy, the immune heterogeneity in patients with unexplained recurrent pregnancy loss (URPL) remains elusive. Here, we profiled the transcriptomes of 13,953 CD45+ cells from three normal and three URPL deciduas. Based on our data, the cellular composition revealed three major populations of immune cells including dNK cell, T cell, and macrophage, and four minor populations including monocytes, dendritic cell (DC), mast cell, and B cell. Especially, we identified a subpopulation of CSF1+ CD59+ KIRs-expressing dNK cells in normal deciduas, while the proportion of this subpopulation was decreased in URPL deciduas. We also identified a small subpopulation of activated dDCs that were accumulated mainly in URPL deciduas. Furthermore, our data revealed that in decidua at early pregnancy, CD8+ T cells exhibited cytotoxic properties. The decidual macrophages expressed high levels of both M1 and M2 feature genes, which made them unique to the conventional M1/M2 classification. Our single-cell data revealed the immune heterogeneity in decidua and the potentially pathogenic immune variations in URPL.