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101.
周期蛋白依赖性激酶4/6(cyclin-dependent kinase 4/6,CDK4/6) 是一类丝氨酸/苏氨酸激酶,通过与细胞周期蛋白D(cyclin D)结合,调节视网膜母细胞瘤蛋白(Rb)的磷酸化状态,Rb磷酸化后与E2F转录因子分离,释放的E2F可以自由激活一系列基因表达,参与DNA复制和细胞分裂,从而介导细胞G1/S期转换,影响细胞周期的进程。近年研究发现CDK4/6在多种肿瘤发生和发展过程中起着核心作用,已成为临床多种肿瘤治疗的重要分子靶点。本文将对CDK4/6与肿瘤的关系以及CDK4/6抑制剂临床应用的最新研究进展做一综述。 相似文献
102.
In nature, calcium deposition is a common biological process in mammals that shapes mechanical structures and creates the functions of bones and teeth, and causes calculi formation. Spontaneous tumor calcification and regional lymph node calcification in colorectal cancer, lung cancer, and glioblastoma have been proven to be benign prognostic factors in the clinic. In line with this concept, we introduce the idea and lead the compound development of artificially inducing bionic calcification around the surface of cancer cells. This process is shown to have excellent effects in the inhibition of growth and metastases of cervical, breast, and lung tumors, as well as superb performance in early-stage diagnosis. Therefore, we predict that this concept may open the door for cancer targeting calcification therapy and diagnosis and provide an outlook for a new avenue in anticancer drug development. 相似文献
103.
Xinxin Huang Juncheng Hao Yan Qin Tan Tao Zhu Vijay Pandey Peter E. Lobie 《International journal of molecular sciences》2022,23(5)
Patients with epithelial ovarian cancer (EOC) are often diagnosed at an advanced stage due to nonspecific symptoms and ineffective screening approaches. Although chemotherapy has been available and widely used for the treatment of advanced EOC, the overall prognosis remains dismal. As part of the intrinsic defense mechanisms against cancer development and progression, immune cells are recruited into the tumor microenvironment (TME), and this process is directed by the interactions between different chemokines and their receptors. In this review, the functional significance of CXC chemokine ligands/chemokine receptors (CXCL/CXCR) and their roles in modulating EOC progression are summarized. The status and prospects of CXCR/CXCL-based theranostic strategies in EOC management are also discussed. 相似文献
104.
Michele Iuliani Sonia Simonetti Giulia Ribelli Andrea Napolitano Umile Giuseppe Longo Bruno Vincenzi Paolo Orsaria Vincenzo Denaro Giuseppe Tonini Daniele Santini Pantano Francesco 《International journal of molecular sciences》2022,23(5)
The CDK4/6 inhibitors (CDKi) palbociclib, ribociclib, and abemaciclib are currently approved in combination with anti-estrogen therapy for the treatment of advanced and/or metastatic hormone receptor-positive/HER2-neu-negative breast cancer patients. Given the high incidence of bone metastases in this population, we investigated and compared the potential effects of palbociclib, ribociclib, and abemaciclib on the breast cancer bone microenvironment. Primary osteoclasts (OCs) and osteoblasts (OBs) were obtained from human monocyte and mesenchymal stem cells, respectively. OC function was evaluated by tartrate-resistant acid phosphatase assay and real-time PCR; OB activity was assessed by an alizarin red assay. OB/breast cancer co-culture models were generated via the seeding of MCF-7 cells on a layer of OBs, and tumor cell proliferation was analyzed using flow cytometry. Here, we showed that ribociclib, palbociclib, and abemaciclib exerted similar inhibitory effects on the OC differentiation and expression of bone resorption markers without affecting OC viability. On the other hand, the three CDKi did not affect the ability of OB to produce bone matrix, even if the higher doses of palbociclib and abemaciclib reduced the OB viability. In OB/MCF-7 co-culture models, palbociclib demonstrated a lower anti-tumor effect than ribociclib and abemaciclib. Overall, our results revealed the direct effects of CDKi on the tumor bone microenvironment, highlighting differences potentially relevant for clinical practice. 相似文献
105.
Stefan Weinschenk Carsten Weiss Justus Benrath Volker von Baehr Thomas Strowitzki Manuel Feißt 《International journal of molecular sciences》2022,23(6)
Background. Local anesthetics (LAs) have potent anti-inflammatory properties. Inflammatory down-regulation is crucial in diseases with overactive immune reactions, such as acute respiratory distress syndrome (ARDS) and chronic inflammation. We investigated the influence of four LAs, procaine, lidocaine, mepivacaine, and bupivacaine, on the reduction of tumor necrosis factor-alpha (TNF-α) secretion in lipopolysaccharide (LPS)-activated human leucocytes. Methods. Blood samples of 28 individuals were stimulated with LPS. The reduction of TNF-α production by each of the four LAs added (0.5 mg/mL) was measured and correlated with biometric variables. A response was defined as reduction to <85% of initial levels. Results. All four LAs down-regulated the TNF-α secretion in 44–61%: Bupivacaine (44.4%), lidocaine (61.5%), mepivacaine (44.4%), and procaine (50% of the individuals, “responders”). The TNF-α secretion was reduced to 67.4, 68.0, 63.6, and 67.1% of the initial values in responders. The effects in both patients and healthy persons were the same. Interindividual responses to LAs were not correlated with the duration or type of complaints, basal TNF-α serum level, sex, BMI, or age of responders. Conclusions. Four clinically relevant LAs (amid-LA and ester-LA) attenuate the inflammatory response provoked by LPS. They are potential candidates for drug repositioning in treating overactive immune reactions and chronic inflammation. 相似文献
106.
Xiaohui Si Lu Xiao Christine E. Brown Dongrui Wang 《International journal of molecular sciences》2022,23(6)
Immunotherapy using chimeric antigen receptor (CAR) T cells is a rapidly emerging modality that engineers T cells to redirect tumor-specific cytotoxicity. CAR T cells have been well characterized for their efficacy against B cell malignancies, and rigorously studied in other types of tumors. Preclinical evaluation of CAR T cell function, including direct tumor killing, cytokine production, and memory responses, is crucial to the development and optimization of CAR T cell therapies. Such comprehensive examinations are usually performed in different types of models. Model establishment should focus on key challenges in the clinical setting and the capability to generate reliable data to indicate CAR T cell therapeutic potency in the clinic. Further, modeling the interaction between CAR T cells and tumor microenvironment provides additional insight for the future endeavors to enhance efficacy, especially against solid tumors. This review will summarize both in vitro and in vivo models for CAR T cell functional evaluation, including how they have evolved with the needs of CAR T cell research, the information they can provide for preclinical assessment of CAR T cell products, and recent technology advances to test CAR T cells in more clinically relevant models. 相似文献
107.
108.
本文基于热断层的思想,提出了用于分析人体内热源信息的一种新的热像图分析方法。通过建立有内热源的热传导微分方程,得出方程的解。再结合实际,应用叠加原理将体表的正常体温和异常热源的温度叠加起来,得出了有内热源的体表温度分布表达式,利用该表达式对红外热像图上可能的病变区域的温度数据进行了分析处理。处理过程中选择了两个参考变量:热源的深度h和热源的发热强度q。深度h对应于肿瘤解剖位置的深度,发热强度q对应于肿瘤的性质:良、恶性的判断。临床病例证明,这两个参数对肿瘤的定性、定位是很有效的。 相似文献
109.
Joanna Bogusiewicz Bogumia Kupcewicz Paulina Zofia Goryska Karol Jaroch Krzysztof Goryski Marcin Birski Jacek Furtak Dariusz Paczkowski Marek Harat Barbara Bojko 《International journal of molecular sciences》2022,23(7)
The development of a fast and accurate intraoperative method that enables the differentiation and stratification of cancerous lesions is still a challenging problem in laboratory medicine. Therefore, it is important to find and optimize a simple and effective analytical method of enabling the selection of distinctive metabolites. This study aims to assess the usefulness of solid-phase microextraction (SPME) probes as a sampling method for the lipidomic analysis of brain tumors. To this end, SPME was applied to sample brain tumors immediately after excision, followed by lipidomic analysis via liquid chromatography-high resolution mass spectrometry (LC-HRMS). The results showed that long fibers were a good option for extracting analytes from an entire lesion to obtain an average lipidomic profile. Moreover, significant differences between tumors of different histological origin were observed. In-depth investigation of the glioma samples revealed that malignancy grade and isocitrate dehydrogenase (IDH) mutation status impact the lipidomic composition of the tumor, whereas 1p/19q co-deletion did not appear to alter the lipid profile. This first on-site lipidomic analysis of intact tumors proved that chemical biopsy with SPME is a promising tool for the simple and fast extraction of lipid markers in neurooncology. 相似文献
110.
Jingwei Shi Xiao Shen Qi Kang Xing Yang Maximilian Denzinger Marko Kornmann Benno Traub 《International journal of molecular sciences》2022,23(7)
In search of new therapies for pancreatic cancer, cytokine pathways have attracted increasing interest in recent years. Cytokines play a vital role in the crosstalk between tumour cells and the tumour microenvironment. The related inflammatory cytokines IL-4 and IL-13 can regularly be detected at increased levels in the microenvironment of pancreatic cancer. They share a receptor heterodimer consisting of IL-4Rα and IL-13Rα1. While IL-4Rα induces a more oncogenic phenotype, the role of IL-13Rα1 was yet to be determined. ShRNA-based knockdown of IL-13Rα1 was performed in Capan-1 and MIA PaCa-2. We assessed cell growth and migratory capacities under the influence of IL-13Rα1. Pathway alterations were detected by immunoblot analysis. We now have demonstrated that the loss of IL-13Rα1 induces apoptosis in pancreatic cancer cells. This was associated with an epithelial-to-mesenchymal transition. Loss of IL-13Rα1 also abolished the effects of exogenous IL-4 and IL-13 stimulation. Interestingly, in wild type cells, cytokine stimulation caused a similar increase in migratory capacities as after IL-13Rα1 knockdown. Overall, our results indicate the vital role of IL-13Rα1 in the progression of pancreatic cancer. The differential expression of IL-4Rα and IL-13Rα1 has to be taken into account when considering a cytokine-targeted therapy in pancreatic cancer. 相似文献