Abstract In one decade, immunotherapy based on immune checkpoint blockades (ICBs) has become a new pillar of cancer treatment following surgery, radiation, chemotherapy, and targeted therapies. However, not all cancer patients benefit from single or combination therapy with anti-CTLA-4 and anti-PD-1/PD-L1 monoclonal antibodies. Thus, an increasing number of immune checkpoint proteins (ICPs) have been screened and their effectiveness evaluated in preclinical and clinical trials. Lymphocyte activation gene-3 (LAG-3), T cell immunoglobulin and mucin-domain-containing-3 (TIM-3), and T cell immunoreceptor with immunoglobulin and tyrosine-based inhibitory motif (ITIM) domain (TIGIT) constitute the second wave of immunotherapy targets that show great promise for use in the treatment of solid tumors and leukemia. To promote the research and clinical application of ICBs directed at these targets, we summarize their discovery, immunotherapy mechanism, preclinical efficiency, and clinical trial results in this review.
Acute promyelocytic leukemia (APL) is characterized by the reciprocal translocation t(15;17), which fuses PML with retinoic acid receptor alpha (RARα). Although PML-RARα is crucially important for pathogenesis and responsiveness to treatment, the molecular and cellular mechanisms by which PML-RARα exerts its oncogenic potential have not been fully elucidated. Recent reports have suggested that long non-coding RNAs (lncRNAs) contribute to the precise control of gene expression and are involved in human diseases. Little is known about the role of lncRNA in APL. We analyzed NEAT1 expression in APL samples and cell lines by real-time quantitative reverse transcription-PCR (qRT-PCR). The expression of PML-RARα was measured by Western blot. Cell differentiation was assessed by measuring the surface CD11b antigen expression by flow cytometry analysis. We found that nuclear enriched abundant transcript 1 (NEAT1), a lncRNA essential for the formation of nuclear body paraspeckles, is significantly repressed in de novo APL samples compared with those of healthy donors. We further provide evidence that NEAT1 expression was repressed by PML-RARα. Furthermore, significant NEAT1 upregulation was observed during all-trans retinoic acid (ATRA)-induced NB4 cell differentiation. Finally, we demonstrate the importance of NEAT1 in myeloid differentiation. We show that reduction of NEAT1 by small interfering RNA (siRNA) blocks ATRA-induced differentiation. Our results indicate that reduced expression of the nuclear long noncoding RNA NEAT1 may play a role in the myeloid differentiation of APL cells.
Abstract Background Medical education in China is in a transitional period, from passive learning models to experiential education. We developed an experiential education method for radiology education. The aim of this study is to evaluate the effect of this method on undergraduate radiology education. Method With the help of the picture archiving and communication system (PACS) and RadiAnt DICOM Viewer, we developed an experiential education method that simulates similar working conditions for undergraduate medical students to formulate radiology diagnosis similar to clinical radiologists. A total of 101 students were allocated into either the experimental group or the control group. The final examination scores and a 5-point Likert scale self-assessment questionnaire of radiologic skills were collected from all the students as an objective assessment and a subjective assessment respectively. A questionnaire was also used to assess the satisfaction with the experiential model in the experimental group. Mann-Whitney U test was used to compare the ranked data, and t-tests were used to compare the numeric data. Results The experimental group demonstrated significantly higher scores (7.4±1.3) compared to the control group (6.7±1.5, p <0.05) in the question type “description and diagnosis”. The self-assessment questionnaire indicated that the experiential education was related to increased familiarity with the diagnosis thinking principle and the sequences and reconstruction methods of computer tomography (CT) imaging, which also strengthen participants’ self-confidence to perform future clinical work (p <0.05). The self-assessment questionnaire in the experimental group showed that the majority of students were satisfied with the organization (82.5%), interactivity (85%) and quality (85%) of the learning activity. Most students found this model of learning to be helpful for studying radiology (85%) and for understanding anatomy (90%). Conclusion Compared with the traditional radiology education approach, the experiential education method showed greater efficacy in improving students’ analysis and diagnostic skills and their self-confidence.
Abstract Background Medical education in China is in a transitional period changing from passive learning to experiential education models. We have modified an experiential education method for radiology education. The aim of this study is to evaluate the effect of this method on undergraduate radiology education. Methods With the help of the picture archiving and communication system (PACS) and RadiAnt DICOM Viewer, we have modified an experiential education method that simulates similar working conditions for undergraduate medical students to take on the role as clinical radiologists and formulate radiology diagnosis. A total of 101 students were allocated into either the experiential education group [Office1] or the control group. The final examination scores and a 5-point Likert scale self-assessment questionnaire of radiologic skills were collected from all the students as an objective assessment and a subjective assessment respectively. A questionnaire was also used to assess the satisfaction with the experiential model in the experiential education group. Mann-Whitney U test was used to compare the ranked data, and t -tests were used to compare the numeric data. Results The experiential education group demonstrated significantly higher scores (7.4±1.3) in the short answer type questions on imaging “description and diagnosis” when compared to the control group (6.7±1.5, p <0.05). The self-assessment questionnaire indicated that the experiential education corresponded to an increased familiarity with the diagnostic principles, the imaging sequences and reconstruction methods of computer tomography (CT), which also strengthen participants’ confidence to perform future clinical work (p <0.05). The self-assessment questionnaire from the experiential education group showed great satisfaction with the organization (82.5%), interactivity (85%) and quality (85%) of the learning activity in majority of students. Most students found this model of learning to be helpful for studying radiology (85%) and for understanding anatomy (90%). Conclusion Compared with the traditional radiology education approach, the experiential education model showed greater efficacy in improving students’ analytical and diagnostic skills as well as clinical confidence.
T cell immunity plays a central role in the body's defense system, including maintaining homeostasis and preventing tumorigenesis and viral infection. Immune system functions degenerate with age, leading to immune senescence. Physiologically, immune senescence is characterized by a decrease in T cell receptor diversity, naive T cell deficiency, and alterations in T cell immune-related miRNAs. However, little is known about the characteristics of T cell immunosenescence in Chinese individuals.A significant decrease in the miR-17, miR-92a, and miR-181a levels in PBMCs was detected with age. The miR-92a and miR-181a levels were upregulated in CBMCs when comparing healthy individuals to group I (0~9 years), whereas miR-17 was downregulated. The sjTREC level in PBMCs was negatively correlated with age, and a sharp decrease in sjTRECs was found between groups I and II (10~19 years). Twenty-four TCR Vβ subfamilies could be detected in most samples, and most displayed polyclonality, while skewed expression of the Vβ subfamilies as well as an increased oligoclonal tendency was found with age. Similarly, the frequencies of the TCR Vγ and Vδ subfamilies decreased with age, and the alteration in clonality appeared to be stable at different ages.We made the novel observation of T cell immunosenescence with age in Chinese individuals, which may provide information for immune targets to enhance the T cell immune response in immunotherapy settings for elderly patients.
Abstract Background & Aims The prevalence of hepatitis delt virus (HDV) far exceeds our expected level, there remains a lack of reliable quantitative assays for HDV RNA detection. We sought to develop a new method based on digital droplet PCR (ddPCR) for HDV RNA quantitative detection. Methods With plasmid (pMD19T) containing HDV full-genome, we determined the method for ddPCR-based HDV RNA quantification. To compare various assays for HDV detection, 30 cases diagnosed hepatitis D and 14 controls were examined by ELISA, RT-PCR and ddPCR. 728 HBV-related patients including 182 chronic hepatitis B (CHB), 182 liver cirrhosis (LC), 182 hepatocellular carcinoma (HCC) and 182 liver failure (LF) were screened for HDV infection. Results The limit of detection of ddPCR for HDV is significantly low, which lower limit of detection (LLoD) and lower limit of quantitation (LLoQ) to be 5.51 copies/reaction (95% CI: 1.15–6.4*105) and 0.18 copies/reaction (95% CI: 0.0012151- 0.76436), respectively. Among the 44 samples, ELISA detected 30 cases positive for anti-HDV, ddPCR reported 24 samples and RT-PCR reported 10 samples positive for HDV RNA. Moreover, the positive rates of anti-HDV IgG were 1.1%, 3.3%, 2.7% and 7.1% in patients with CHB, LC, HCC, and LF; the detection rates of RT-PCR in HDV RNA were 0%, 16.67%, 15.4% and 20%, however, the detection rates of ddPCR were 0%, 33.33%, 30.77% and 60%. Conclusion We establish a high sensitivity and high specificity quantitative HDV RNA detection method based on ddPCR compared to RT-PCR. HBV-related end-stage liver disease, especially liver failure, are associated with a remarkably high rate of HDV infection.
A20 is a dual inhibitor of NF-κB activation and apoptosis in the tumor necrosis factor receptor 1 signaling pathway, and both are related to tumorigenesis. A20 is frequently inactivated by deletions and/or mutations in several B and T cell lymphoma subtypes; however, knowledge of the role of A20 in B-cell acute lymphoblastic leukemia (B-ALL) remains limited. In this study, we characterized the A20 gene expression pattern, the expression level of its upstream regulating factor MALT1, and its downstream target NF-κB in adult B-ALL.The expression level of MALT1, A20 and NF-κB1 was detected in peripheral blood mononuclear cells (PBMCs) from 20 patients with adult B-ALL (including 12 de novo B-ALL and 8 refractory/relapse B-ALL cases), and nine patients with B-ALL in complete remission (CR) using real-time PCR. Sixteen healthy individuals served as controls.Significant A20 overexpression was found in the B-ALL (median: 13.489) compared with B-ALL CR (median: 3.755) (P = 0.003) patients and healthy individuals (median: 8.748) (P = 0.002), while there was no significant difference in A20 expression between B-ALL CR patients and healthy individuals (P = 0.107). Interestingly, the A20 expression level in the B-ALL samples was relatively different with approximately 50% of the B-ALL cases showing a relatively high A20 expression level, while the remaining 50% cases demonstrated slight upregulation or a similar expression level as the healthy controls. However, there was no significant difference in the A20 expression level between de novo B-ALL (median 12.252) and refractory/relapse B-ALL patients (median 21.342) (P = 0.616). Similarly, a significantly higher expression level of NF-κB1 was found in the B-ALL (median 1.062) patients compared with healthy individuals (median 0.335) (P < 0.0001), while the NF-κB1 expression level was downregulated in the B-ALL CR group (median 0.339), which was significantly lower than that in those with B-ALL (P = 0.001). Moreover, the MALT1 expression level in B-ALL was upregulated (median 1.938) and significantly higher than that in healthy individuals (median 0.677) (P = 0.002) and B-ALL CR patients (median 0.153) (P = 0.008). The correlation of the expression levels of all three genes was lost in B-ALL.We found that MALT1-A20-NF-κB is overexpressed in adult B-ALL, which may be related to the pathogenesis of B-ALL, and this pathway may be considered a potentially attractive target for the development of B-ALL therapeutics.
Acute myeloid leukemia (AML) is a malignant clonal tumor originating from immature myeloid hematopoietic cells in the bone marrow with rapid progression and poor prognosis. Therefore, an in-depth exploration of the pathogenesis of AML can provide new ideas for the treatment of AML. In recent years, it has been found that exosomes play an important role in the pathogenesis of AML. Exosomes are membrane-bound extracellular vesicles (EVs) that transfer signaling molecules and have attracted a large amount of attention, which are key mediators of intercellular communication. Extracellular vesicles not only affect AML cells and normal hematopoietic cells but also have an impact on the bone marrow microenvironment and immune escape, thereby promoting the progression of AML and leading to refractory relapse. It is worth noting that exosomes and the various molecules they contain are expected to become the new markers for disease monitoring and prognosis of AML, and may also function as drug carriers and vaccines to enhance the treatment of leukemia. In this review, we mainly summarize to reveal the role of exosomes in AML pathogenesis, which helps us elucidate the application of exosomes in AML diagnosis and treatment.
T-cell receptor (TCR) repertoire analyses have been widely used to identify T cell populations of interest in cancer and autoimmunity and for characterizing immune repertoire reconstitution after hematopoietic stem cell transplantation (HSCT). Several decades of development and progress have led to the use of techniques for evaluating TCR repertoires in a more comprehensive, unbiased and fast manner, and the mechanisms of T cell immune reconstitution after HSCT and the new approaches used for recovering T cell repertoire diversity post HSCT have been more exhaustively documented to some degree. To better understand and characterize this progress, here we review recent studies on TCR repertoire diversity recovery in patients with leukemia and autoimmune disease who have received HSCT, impact factors and improvements in approaches for TCR repertoire recovery after HSCT.