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131.
In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2–3′UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.  相似文献   
132.
Accumulated evidence has shown that pre-eclampsia (PE) is related to both maternal and utero-placental antiangiogenesis and inflammation. Remarkably, an elevated cell-free fetal DNA (cffDNA) level has been found in maternal circulation; however, it remains unclear whether this DNA can induce activation of cytosolic DNA sensor signaling pathways and lead to the development of PE. In this study, we found that trophoblast cells constitutively expressed the cytosolic DNA sensors, absent in melanoma 2 (AIM2) and interferon-inducible protein 16 (IFI16). The cffDNA and pro-inflammatory and antiangiogenic factors were present at higher concentrations in PE compared with the control group and correlated with the severity of PE. DNA stimulation significantly increased the AIM2 and IFI16 levels, consistent with the elevated AIM2 and IFI16 expression in women with PE, and elicited increased production of AIM2-mediated interleukin IL-8 (IL-8), IL-6 and CC chemokine ligand 2 (CCL2) and IFI16-mediated sEndoglin, sFlt-1 and CXCL10. Furthermore, enhancement of the inflammatory response was found to be induced by DNA exposure, but DNA exposure did not induce PE-like symptoms in pregnant mice. It is possible that elevated cffDNA could reflect the degree of placental damage and trigger cytosolic DNA sensor activation, which disrupts the immunity balance and, consequently, contributes to inflammatory and antiangiogenic responses. In conclusion, the results of this study suggest that circulating cffDNA levels are increased in preeclamptic women and act through AIM2 and IFI16 activation to promote the production of pro-inflammatory and antiangiogenic factors, which correlate with the severity of the disease, and may offer insights into the etiology and pathogenesis of PE.  相似文献   
133.
We report a case of mucocutaneous phaeohyphomycosis caused by Exophiala spinifera. Crusty plaques and nodules were major clinical features. Histological examination revealed brown yeast-like cells and hyphae. Mycological and molecular data identified E. spinifera as etiologic agent. Oral itraconazole was effective, which was in accordance with the results of in vitro susceptibility testing. We speculated that her pregnancy may play a role of risk factor in the infection by E. spinifera.  相似文献   
134.
The intrinsic rate of increase (rm) has been considered as an important indicator of fitness in terrestrial ectotherms since long. It is actually an equivalent to the instantaneous growth rate of the exponential equation for describing the density-independent population growth. In terrestrial ectotherms, rm has been demonstrated to be temperature-dependent. The temperature at which rm was maximal, was considered to be the “optimal” temperature for fitness in Amarasekare and Savage (2012), but this definition needs further analysis. Only rm cannot provide thorough representation of fitness. Because body size can affect the competitive abilities in many terrestrial ectotherms, both population size and body size should be considered in measuring the fitness of ectotherms. The rule of “bigger is better” requires relatively low temperature to increase in body size, whereas relatively high temperature is required for a rapid increase in population size. Thus, there is presumably a trade-off in temperature for adjusting individual body size and population size to achieve maximum fitness. We hypothesized that this temperature could be reflected by the intrinsic optimum temperature for developmental rate in the Sharpe–Schoolfield–Ikemoto model, and it led to a temperature estimate around 20 °C. However, the traditional viewpoint based on the temperature corresponding to the maximal intrinsic rate of increase provides a temperature estimate around 30 °C. This study suggests that a low temperature around 20 °C might authentically represent the optimal ambient temperature for fitness in terrestrial ectotherms. It implies that thermal biologists who are interested in the effect of temperature on the fitness in terrestrial ectotherms should pay more attention to their performance at low temperature rather than high temperature.  相似文献   
135.

Background

The bone marrow (BM) of breast cancer patients harbors tumor-reactive memory T cells (TCs) with therapeutic potential. We recently described the immunologic effects of adoptive transfer of ex vivo restimulated tumor-reactive memory TCs from the BM of 12 metastasized breast cancer patients in a clinical phase-I study. In this trial, adoptive T cell transfer resulted in the occurrence of circulating tumor antigen-reactive type-1 TCs. We here describe the long-term clinical outcome and its correlation with tumor-specific cellular immune response in 16 metastasized breast cancer patients, including 12 included in the original study.

Methods

Sixteen metastatic breast cancer patients with preexisting tumor-reactive BM memory TCs were included into the study. The study protocol involved one transfusion of TCs which were reactivated in vitro with autologous dendritic cells pulsed with lysates of MCF-7 breast cancer cells as source of tumor antigens. The presence of tumor-reactive memory TCs was analyzed by IFN-γ ELISpot assays.

Results

Tumor-reactive memory TCs in the peripheral blood were induced de novo in 7/16 patients (44 %) after adoptive TC transfer. These patients were considered immunologic responders to the therapy. Positive adoptive immunotherapy (ADI) response was observed significantly more often in patients without bone metastases (p = 0.0051), in patients with high levels of tumor-reactive BM TCs prior to therapy (p = 0.036) and correlated significantly with the estimated numbers of transferred tumor-reactive TCs (p = 0.0021). After the treatment, we observed an overall median survival of 33.8 months in the total cohort with three patients alive at last follow-up and more than 7 years after ADI. Numbers of transferred tumor-reactive TCs correlated significantly with the overall survival of patients (p = 0.017). Patients with an immunologic response to ADI in the peripheral blood had a significantly longer median survival than nonresponders (median survival 58.6 vs. 13.6 months; p = 0.009).

Conclusion

In metastasized breast cancer patients, adoptive transfer of BM TCs can induce the presence of tumor antigen-reactive type-1 TCs in the peripheral blood. Patients with immunologic response after ADI show a significantly longer overall survival. Patients with bone metastases significantly less frequently respond to the treatment and, therefore, might not be optimal candidates for ADI. Although the present study does not yet prove the therapeutic effect of ADI, these findings shed light on the relation between immune response and cancer prognosis and suggest that transfer of reactivated BM TCs might bear therapeutic potential.  相似文献   
136.
Human DOC-2/DAB2 interactive protein (hDAB2IP) gene is a novel member of the Ras GTPase-activating family and has been demonstrated to be a tumor-suppressor gene that inhibits cell survival and proliferation and induces cell apoptosis. It was reported that the expression level of hDAB2IP in gastric cancer tissue was highly correlated with tumor progression, however, whether hDAB2IP genetic variants are associated with the risk of gastric cancer remains yet unknown. In this case–control study, we conducted a genetic analysis for hDAB2IP variants in 311 patients with gastric cancer and 425 controls from the Chinese Han population. We found that the SNP rs2243421 of hDAB2IP gene with the minor allele C significantly revealed strong association with decreased gastric cancer susceptibility (P = 0.007, adjusted odds ratio [OR] = 0.734, 95%CI = 0.586–0.919). Haplotypes rs2243421 and rs10985332 (HaploType: CC, P = 0.012, aOR = 0.760) and haplotypes rs2243421 and rs555996 (HaploType: CG, P = 0.034, aOR = 0.788) represented the decreased risk of gastric cancer, respectively. On the contrary, rs2243421 and rs555996 showed an elevated susceptibility (HaploType: TG, P = 0.010, aOR = 1.320). Our results for the first time provided new insight into susceptibility factors of hDAB2IP gene variants in carcinogenesis of gastric cancer.  相似文献   
137.
138.
Insulin-like peptide 3 (INSL3) is a reproduction-related peptide hormone belonging to the insulin/relaxin superfamily, which mediates testicular descent in the male fetus, suppresses male germ cell apoptosis and promotes oocyte maturation in adults by activating the relaxin family peptide receptor 2 (RXFP2). To establish an ultrasensitive receptor-binding assay for INSL3−RXFP2 interaction studies, in the present work we labeled a recombinant INSL3 peptide with a newly developed nanoluciferase (NanoLuc) reporter through a convenient chemical conjugation approach, including the introduction of an active disulfide bond to INSL3 by chemical modification and engineering of a 6× His-Cys-NanoLuc carrying a unique exposed cysteine at the N-terminus. The bioluminescent NanoLuc-conjugated INSL3 retained high binding affinity with the target receptor RXFP2 (Kd = 2.0 ± 0.1 nM, n = 3) and was able to sensitively monitor the receptor-binding of a variety of ligands, representing a novel ultrasensitive tracer for non-radioactive receptor-binding assays. Our present chemical conjugation approach could readily be adapted for conjugation of NanoLuc with other proteins, even other macrobiomolecules, for various highly sensitive bioluminescent assays.  相似文献   
139.
Previous study in our laboratory confirmed that a novel polypeptide, CS5931 derived from Ciona savignyi possesses potent antitumor activity. In the present study, the full length cDNA of CS5931 precursor, termed Cs-pgrn-1 was cloned. The complete cDNA sequence of this gene consists of 685 bp containing an open reading frame (ORF) of 522 bp (173 amino acid residues). In silico analysis revealed that the polypeptide consists of two identical domains, similar with granulin (GRN) found in other species, and each of the domain encodes a polypeptide identical with CS5931. Phylogenetic analysis confirmed that CS5931 shares high homology with Ciona intestinalis GRN and is conserved during evolution. The polypeptide also shows high similarity with human GRN A, B, and C. Prediction of 3D protein structure revealed the 3D structure of CS5931 is very similar with human GRN A. The CS5931 was expressed using a prokaryotic expression system and the purified polypeptide inhibited the growth of several tumor cell lines in vitro via apoptotic pathway. Our study revealed that CS5931 has the potential to be developed as a novel antitumor agent.  相似文献   
140.
The over-expression of tissue factor (TF) and its roles in colon cancer progression have attracted much attention. However, the mechanisms regulating TF expression have not yet been shown in detail. In this study, we over-expressed miR-19a, miR20a and miR-106b in colon cancer cells, and evaluated their impact on TF expression and cellular function. We provide evidence demonstrating that miR-19a inhibited TF expression in vitro. Luciferase reporter assay confirmed that TF was a direct target of miR-19a because the miR-19a mediated repression of luciferase activity was abolished by mutation of the putative binding site. Moreover, miR-19a suppressed colon cancer cell migration and invasion. This effect was due to the indirect down-regulation of matrix metalloproteinase 9. Finally, we investigated the relevance of TF and miR-19a expression in a total of 48 paired colon cancer samples and revealed that miR-19a was inversely correlated with TF expression in stages I and II cases. Therefore, our results suggested that miR-19a was capable of suppressing TF expression in vitro and inhibiting cell migration and invasion. Although it was not the unique mechanism responsible for the expression of TF in vivo, miR-19a was inversely correlated with TF expression in early stage colon cancer patients.  相似文献   
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