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111.
前列腺癌是中国发病率增长最快的男性肿瘤,抗雄激素治疗耐药是导致前列腺癌患者预后差的主要原因。因此,解决耐药性难题是前列腺癌转化研究的关键问题。哺乳动物细胞利用泛素-蛋白酶体系统实现蛋白质的靶向降解。因此,前列腺癌中关键的癌基因如雄激素受体(AR)的上游泛素化调控因子(如去泛素化酶)是潜在的治疗靶点。然而,这些酶具有较广的底物谱系,存在脱靶的可能性。近来,基于泛素-蛋白酶体系统开发的蛋白质降解靶向嵌合体(proteolysis-targeting chimeras,PROTAC)技术是最具前景和革命性的新型抗癌药物研发技术,能够利用特定E3泛素连接酶对靶蛋白进行降解而不影响其他底物。与传统小分子抑制剂相比,PROTAC分子在克服耐药性以及针对不可成药的靶点方面拥有巨大优势。目前,针对AR的PROTAC降解剂已在II期临床取得了成功,靶向蛋白质泛素化及降解途径的新技术将有望为前列腺癌的临床治疗带来新的突破。  相似文献   
112.
胰腺癌症是最难诊断和治疗的恶性肿瘤之一,其特点是发病隐匿、进展迅速、预后差。目前,手术治疗仍然是首选治疗方法。然而由于缺乏早期症状,大约70%的患者在确诊时已经出现局部扩散或远端转移,从而无法进行手术治疗。由此看来,早期检测是提高患者治疗效果和预后的有效途径。临床上使用的成像方法 (CT、MRI、EUS等)通常无法检测早期病变,并且很容易受到操作员的影响。常规临床标志物如CA19-9、CA125、CA242和CEA受到限制,其敏感性或特异性不令人满意。因此,寻找新的具有高敏感性和特异性的标志物是实现胰腺癌早期检测的关键。近年来,对生物标志物的广泛研究主要集中在遗传学、转录组学和蛋白质组学上。特别是由microRNA(miRNA)、long non-coding RNA(lncRNA)和circRNA(circRNA)组成的非蛋白质编码RNA(non-protein coding RNA,ncRNA)为胰腺癌的早期检测提出了许多新思路。然而,其中绝大多数仍处于实验室研究阶段。而一项成熟的生物标志物研究应该整合基因组学、转录组学、蛋白质组学或代谢组学的数据,并结合患者的个体特征(如体重指数...  相似文献   
113.
为研究白花蛇舌草(Hedyotis diffusa)的化学成分,采用硅胶柱色谱、制备HPLC色谱等方法,从白花蛇舌草全草的70%乙醇提取物中分离得到9个化合物。根据理化性质及其波谱或光谱数据,结构分别鉴定为:豆甾醇(1)、β-谷甾醇(2)、rubiadin(3)、2,6-二羟基-1-甲氧基蒽醌(4)、β-谷甾醇-3-O-β-D-葡萄糖苷(5)、对香豆酸(6)、山奈酚(7)、槲皮素(8)和2-羟基-3-甲氧基-7-甲基蒽醌(9)。化合物4为新化合物;氯仿提取部位的Fr.4、Fr.4-2及Fr.4-4流分具有较强体外抗人子宫内膜癌Ishikawa细胞活性,其IC50值分别为52.8、78.1和27.5μg/mL。  相似文献   
114.
115.
Cervical cancer is still an important cause of death in countries like Colombia. We aimed to determine whether socioeconomic status of residential address (SES) and type of health insurance affiliation (HIA) might be associated with cervical cancer survival among women in Bucaramanga, Colombia. All patients residing in the Bucaramanga Metropolitan Area diagnosed with invasive cervical cancer (ICD-0–3 codes C53.X) between 2008 and 2016 (n = 725) were identified through the population-based cancer registry, with 700 women having follow-up data for >5 years (date of study closure: Dec 31, 2021), yielding an overall 5-year survival estimate (95 % CI) of 56.4 % (52.7 – 60.0 %). KM estimates of 5-year overall survival were obtained to assess differences in cervical cancer survival by SES and HIA. Multivariable Cox-proportional hazards modeling was also conducted, including interaction effects between SES and HIA. Five-year overall survival was lower when comparing low vs. high SES (41.9 % vs 57.9 %, p < 0.0001) and subsidized vs. contributive HIA (45.1 % vs 63.0 %, p < 0.0001). Multivariable Cox modeling showed increased hazard ratios (HR) of death for low vs. high SES (HR = 1.78; 95 % CI = 1.18–2.70) and subsidized vs. contributive HIA (HR = 1.44; 95 % CI = 1.13–1.83). The greatest disparity in HR was among women of low SES affiliated to subsidized HIA (vs. contributive HIA and high SES) (HR=2.53; 95 % CI = 1.62–3.97). Despite Colombia’s universal healthcare system, important disparities in cervical cancer survival by health insurance affiliation and socioeconomic status remain.  相似文献   
116.
BackgroundBreast cancer screening programs were introduced in many countries worldwide following randomized controlled trials in the 1980s showing a reduction in breast cancer-specific mortality. However, their effectiveness remains debated and estimates vary. A breast cancer screening program was introduced in 2001 in Flanders, Belgium where high levels of opportunistic screening practices are observed. The effectiveness of this program was estimated by measuring its effect on breast cancer-specific mortality.MethodsWe performed a case-referent study to investigate the effect of participation in the Flemish population-based mammography screening program (PMSP) on breast cancer-specific mortality from 2005 to 2017. A multiple logistic regression model assessed the association between breast cancer-specific death and screening program participation status in the four years prior to (pseudo)diagnosis (yes/no), with adjustment for potential confounders (individual socio-economic position and calendar year of diagnosis) and stratified for age. In addition, we performed different sensitivity analyses.ResultsWe identified 1571 cases and randomly selected 6284 referents. After adjustment, women who participated in PMSP had a 51 % lower risk of breast cancer-specific mortality compared to those who did not (adjusted odds ratio [aOR] =0.49, 95 % CI: 0.44–0.55). Sensitivity analyses did not markedly change the estimated associations. Correction for self-selection bias reduced the effect size, but the estimate remained significant.ConclusionOur results indicate that in a context of high opportunistic screening rates, participation in breast cancer screening program substantially reduces breast cancer-specific mortality. For policy, these results should be balanced against the potential harms of screening, including overdiagnosis and overtreatment.  相似文献   
117.
BackgroundAn increasing trend of oropharyngeal cancer (OPC) has been reported in several countries with different demographic characteristics, and often attributed to increases in human papillomavirus (HPV) infection. The survival of patients with OPC has steadily improved, especially for those with positive HPV status. This study assessed the incidence, trends, and survival of OPC in Aotearoa New Zealand (NZ) by age at diagnosis, sex and ethnicity.MethodsThe study included all 2109 patients resident in NZ with a primary diagnosis of oropharyngeal squamous cell carcinoma from 2006 to 2020, identified from the National Cancer Registry. We assessed age-standardised incidence rate (ASR), annual percent change (APC) and overall and relative survival rates.ResultsThe average annual incidence of OPC was 2.2 per 100,000 population. There was a steady increase of 4.9% per year over 15 years. Although the incidence rates were higher in males over the study period, the overall rate of increase was similar in males (4.9%) and in females (4.3%). The incidence was highest in the 50–69-year group (8.8/100,000 population). This age group had an incidence that increased by 7.5% per year to 2018, and then declined. The main increase in rates was seen between the birth cohort of 1946–50 and that of 1956–60. The increase in incidence was seen in Māori and Pākehā/European populations, but no increase was seen in Pacific or Asian populations. The 5-year overall relative survival rate improved from 69% in 2006‐13 to 78% in 2014–20. Survival rates were lower in older patients, females, and Māori patients.ConclusionThis study confirmed a substantial increase in OPC incidence in NZ, with some evidence to suggest a recent slowing in this increase. Māori and Pākehā/European had the highest incidence, while Pacific and Asian populations showed the lowest rates and no increase over the study period. Survival rates have improved over time, but remained lower in some demographic groups.  相似文献   
118.
Aptamers (Apts) are synthetic nucleic acid ligands that can be engineered to target various molecules, including amino acids, proteins, and pharmaceuticals. Through a series of adsorption, recovery, and amplification steps, Apts are extracted from combinatorial libraries of synthesized nucleic acids. Using aptasensors in bioanalysis and biomedicine can be improved by combining them with nanomaterials. Moreover, Apt-associated nanomaterials, including liposomes, polymeric, dendrimers, carbon nanomaterials, silica, nanorods, magnetic NPs, and quantum dots (QDs), have been widely used as promising nanotools in biomedicine. Following surface modifications and conjugation with appropriate functional groups, these nanomaterials can be successfully used in aptasensing. Advanced biological assays can use Apts immobilized on QD surfaces through physical interaction and chemical bonding. Accordingly, modern QD aptasensing platforms rely on interactions between QDs, Apts, and targets to detect them. QD-Apt conjugates can be used to directly detect prostate, ovarian, colorectal, and lung cancers or simultaneously detect biomarkers associated with these malignancies. Tenascin-C, mucin 1, prostate-specific antigen, prostate-specific membrane antigen, nucleolin, growth factors, and exosomes are among the cancer biomarkers that can be sensitively detected using such bioconjugates. Furthermore, Apt-conjugated QDs have shown great potential for controlling bacterial infections such as Bacillus thuringiensis, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Campylobacter jejuni, Staphylococcus aureus, and Salmonella typhimurium. This comprehensive review discusses recent advancements in the design of QD-Apt bioconjugates and their applications in cancer and bacterial theranostics.  相似文献   
119.
Pancreatic cancer is a highly aggressive form of cancer with a poor prognosis, partly due to ‘austerity’, a phenomenon of tolerance to nutrient deprivation and survival in its hypovascular tumor microenvironment. Anti-austerity agents which preferentially diminish the survival of cancer cells under nutrition starvation is regarded as new generation anti-cancer agents. This study investigated the potential of Piper longum constituents as anti-austerity agents. The ethanolic extract of Piper longum was found to have preferential cytotoxicity towards PANC-1 human pancreatic cancer cells in a nutrient-deprived medium (NDM). Further investigation led to the identification of pipernonaline ( 3 ) as the lead compound with the strongest anti-austerity activity, inducing cell death and inhibiting migration in a normal nutrient medium, as well as strongly inhibiting the Akt/mTOR/autophagy pathway. Therefore, pipernonaline ( 3 ) holds promise as a novel antiausterity agent for the treatment of pancreatic cancer.  相似文献   
120.
Long non-coding RNAs (lncRNA) have an extensive role in the progression and chemoresistance of gastric cancer (GC). Deeply study the regulatory role of lncRNAs could provide potential therapeutic targets. The aim of this study is to explore the regulatory role of HOTAIR in the progression and oxaliplatin resistance of GC. The expression of HOTAIR in GC and cell lines were detected by using qRT-PCR. Cell proliferation and apoptosis were analysed by CCK-8, EdU incorporation and flow cytometry. Luciferase reporter assay was used to identify the interaction between HOTAIR and ABCG2 (ATP-binding cassette (ABC) superfamily G member 2, ABCG2) via miR-195-5p. The regulatory functions were verified by using molecular biology experiments. HOTAIR was significantly overexpressed in GC and associated with poor prognosis. Knock-down of HOTAIR inhibited the GC cells proliferation and oxaliplatin resistance, while overexpression of HOTAIR showed opposite functions. Further studies found that HOTAIR acted as a competing endogenous RNA (ceRNA) to absorb miR-195-5p and elevated the expression of ABCG2, which leads to resistance of GC cells to oxaliplatin. Taken together, our findings demonstrated that HOTAIR regulates ABCG2 induced resistance of GC to oxaliplatin through miR-195-5p signalling and illustrate the great potential of developing new therapeutic targets for GC patients.  相似文献   
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