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91.
92.

Background

Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of metastatic renal cell carcinoma (mRCC). We aimed to assess the association between the baseline values and treatmentrelated modifications of total serum cholesterol (C), triglycerides (T), body mass index (BMI), fasting blood glucose level (FBG) and blood pressure (BP) levels and the outcome of patients treated with everolimus for mRCC.

Methods

177 patients were included in this retrospective analysis. Time to progression (TTP), clinical benefit (CB) and overall survival (OS) were evaluated.

Results

Basal BMI was significantly higher in patients who experienced a CB (p=0,0145). C,T and C+T raises were significantly associated with baseline BMI (p=0.0412, 0.0283 and 0.0001). Median TTP was significantly longer in patients with T raise compared to patients without T (10 vs 6, p=0.030), C (8 vs 5, p=0.042) and C+T raise (10.9 vs 5.0, p=0.003). At the multivariate analysis, only C+T increase was associated with improved TTP (p=0.005). T raise (21.0 vs 14.0, p=0.002) and C+T increase (21.0 vs 14.0, p=0.006) were correlated with improved OS but were not significant at multivariate analysis.

Conclusion

C+T raise is an early predictor for everolimus efficacy for patients with mRCC.  相似文献   
93.
The direct correlation between teratological cases and phytoplasma infections was ascertained in spontaneous and cultivated plant species. Plants, belonging to 31 species and 12 families, showing symptoms of growth abnormalities were collected and analysed. Attempted detection of Rhodococcus fascians by isolation, PCR indexing and 16S rRNA sequencing from fasciated tissues allowed to exclude its presence. Nested PCR by universal primers and 16S rRNA sequence analyses indicated the presence of phytoplasmas, belonging to six groups, in the 44% of symptomatic samples. Among the infected species, Austrocylindropuntia exaltata, Opuntia subulata, Euphorbia characias, Euphorbia dendroides, Euphorbia linifolia, Euphorbia myrsinites, Rumex buchephalophorus, Linaria multicaulis and Fedia cornucopiae represent new phytoplasma hosts world-wide. Moreover this is the first report of phytoplasma belonging to subgroup 16SrRNA II-I in Italy. These findings together with the known erratic distribution in plant tissues of these phloem-restricted prokaryotes indicate a close correlation between fasciation and similar growth disorders and phytoplasma infections.  相似文献   
94.
Development of cervical cancer is directly associated with integration of human papillomavirus (HPV) genomes into host chromosomes and subsequent modulation of HPV oncogene expression, which correlates with multi-layered epigenetic changes at the integrated HPV genomes. However, the process of integration itself and dysregulation of host gene expression at sites of integration in our model of HPV16 integrant clone natural selection has remained enigmatic. We now show, using a state-of-the-art ‘HPV integrated site capture’ (HISC) technique, that integration likely occurs through microhomology-mediated repair (MHMR) mechanisms via either a direct process, resulting in host sequence deletion (in our case, partially homozygously) or via a ‘looping’ mechanism by which flanking host regions become amplified. Furthermore, using our ‘HPV16-specific Region Capture Hi-C’ technique, we have determined that chromatin interactions between the integrated virus genome and host chromosomes, both at short- (<500 kbp) and long-range (>500 kbp), appear to drive local host gene dysregulation through the disruption of host:host interactions within (but not exceeding) host structures known as topologically associating domains (TADs). This mechanism of HPV-induced host gene expression modulation indicates that integration of virus genomes near to or within a ‘cancer-causing gene’ is not essential to influence their expression and that these modifications to genome interactions could have a major role in selection of HPV integrants at the early stage of cervical neoplastic progression.  相似文献   
95.
96.
Emerging evidence suggests that metformin, a widely used anti-diabetic drug, may be useful in the prevention and treatment of different cancers. In the present study, we demonstrate that metformin directly inhibits the enzymatic function of hexokinase (HK) I and II in a cell line of triple-negative breast cancer (MDA-MB-231). The inhibition is selective for these isoforms, as documented by experiments with purified HK I and II as well as with cell lysates. Measurements of 18F-fluoro-deoxyglycose uptake document that it is dose- and time-dependent and powerful enough to virtually abolish glucose consumption despite unchanged availability of membrane glucose transporters. The profound energetic imbalance activates phosphorylation and is subsequently followed by cell death. More importantly, the “in vivo” relevance of this effect is confirmed by studies of orthotopic xenografts of MDA-MB-231 cells in athymic (nu/nu) mice. Administration of high drug doses after tumor development caused an evident tumor necrosis in a time as short as 48 h. On the other hand, 1 mo metformin treatment markedly reduced cancer glucose consumption and growth. Taken together, our results strongly suggest that HK inhibition contributes to metformin therapeutic and preventive potential in breast cancer.  相似文献   
97.
Cells of colonic mucosa are sensitive to the Smad-mediated growth-inhibitory effect of transforming growth factor-beta1 (TGF-beta1). Another important cell growth inhibitor is the polyunsaturated lipid peroxidation end product, 4-hydroxynonenal (HNE), which triggers apoptosis through c-Jun N-terminal kinase (JNK) activation. Interestingly, a close association between TGF-beta1 and HNE was found in the progression of human colon cancer, with concentration of both molecules inversely related to the malignancy. We investigated the cross talk between Smads and JNK signal transduction pathways in inducing apoptosis. To this purpose TGF-beta1 and HNE were added singly or in combination to CaCo-2 human colon adenocarcinoma cells. The cotreatment induced a marked enhancement of apoptosis and of JNK and Smad4 activities much more than either individual molecule. Cell preincubation with the JNK inhibitor SP600125 significantly prevented JNK and Smad4 enhancement and, subsequently, the cooperative proapoptotic effect was abolished. The primary role of JNK activity in TGF-beta1/HNE cooperative signaling was fully confirmed in a second set of experiments by using JNKi I, a more selective kinase inhibitor. Hence, in tumor cells becoming resistant to TGF-beta1-mediated growth inhibition, increased induction of the remaining TGF-beta1 pathways by interaction with other antiproliferative molecules, such as HNE, could help in inhibiting tumor growth.  相似文献   
98.
The expansion of a polymorphic CAG repeat in the HD gene encoding huntingtin has been identified as the major cause of Huntington’s disease (HD) and determines 42–73% of the variance in the age-at-onset of the disease. Polymorphisms in huntingtin interacting or associated genes are thought to modify the course of the disease. To identify genetic modifiers influencing the age at disease onset, we searched for polymorphic markers in the GRIK2, TBP, BDNF, HIP1 and ZDHHC17 genes and analysed seven of them by association studies in 980 independent European HD patients. Screening for unknown sequence variations we found besides several silent variations three polymorphisms in the ZDHHC17 gene. These and polymorphisms in the GRIK2, TBP and BDNF genes were analysed with respect to their association with the HD age-at-onset. Although some of the factors have been defined as genetic modifier factors in previous studies, none of the genes encoding GRIK2, TBP, BDNF and ZDHHC17 could be identified as a genetic modifier for HD.Electronic Supplementary Material Supplementary material is available to authorised users in the online version of this article at .  相似文献   
99.
Compelling evidence indicates that some endocrine disrupters (EDs), acting as selective estrogen-receptor modulators, interfere with osteoblast differentiation and function. Hence, we investigated whether four EDs [bisphenol-A (BSP), benzophenone-3 (BP3), resveratrol and silymarin] affect differentiation and growth of rat calvarial osteoblast-like (ROB) cells in primary in vitro culture. ROB cells were cultured for up 30 days in a medium supplemented with fetal calf serum (FCS), and conventional RT-PCR detected the expression of collagen-1alpha and osteonectin mRNAs through the entire culture period. Real time-PCR demonstrated that at days 2 and 7 of culture the expressions of collagen-1alpha and osteonectin were very low, and underwent a 192- and a 334-fold increase, respectively, at day 21 of culture. In contrast, osteocalcin expression remained unchanged from days 2 to 21 of culture. EIA showed that ROB cells secreted sizeable amounts of osteocalcin and osteopontin between days 13 and 15 of culture. EDs were added at day 13 of culture at concentrations ranging from 10(-10) to 10(-6) M, being the culture medium deprived of FCS, and their effects were tested 48 h later. None of EDs was found to affect osteocalcin and osteopontin secretion from ROB cells, suggesting that their effects were tested at a relatively earlier stage of culture, when ROB cell differentiation into osteoblats is not fully accomplished, and/or the presence of estrogens contained in FCS is needed for EDs to exert their osteoblast-differentiation modulating action. BSP and BP3, but not resveratrol and silymarin, decreased proliferative activity of cultured ROB cells, a cytotoxic effect conceivably independent of their estrogen-receptor modulating activity.  相似文献   
100.
Morphology of extant felids is regarded as highly conservative. Most previous studies have focussed on skull morphology, so a vacuum exists about morphofunctional variation in postcranium and its role in structuring ensembles of felids in different continents. The African felid ensemble is particularly rich in ecologically specialized felids. We studied the ecomorphology of this ensemble using 31 cranial and 93 postcranial morphometric variables measured in 49 specimens of all 10 African species. We took a multivariate approach controlling for phylogeny, with and without body size correction. Postcranial and skull + postcranial analyses (but not skull‐only analyses) allowed for a complete segregation of species in morphospace. Morphofunctional factors segregating species included body size, bite force, zeugopodial lengths and osteological features related to parasagittal leg movement. A general gradient of bodily proportions was recovered: lightly built, long‐legged felids with small heads and weak bite forces vs. the opposite. Three loose groups were recognized: small terrestrial felids, mid‐to‐large sized scansorial felids and specialized Acinonyx jubatus and Leptailurus serval. As predicted from a previous study, the assembling of the African felid ensemble during the Plio‐Pleistocene occurred by the arrival of distinct felid lineages that occupied then vacant areas of morphospace, later diversifying in the continent.  相似文献   
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