Immunotherapy has been introduced into cancer treatment methods, but different problems have restricted the efficacy of these protocols in clinical trials such as the presence of various immunomodulatory factors in the tumor microenvironment. Adenosine is an immunosuppressive metabolite produced by the tumor to promote growth, invasion, metastasis, and immune evasion. Many studies about adenosine and its metabolism in cancer have heightened interest in pursuing this treatment approach. It seems that targeting the adenosine pathway in combination with immunotherapy may lead to efficient antitumor response. In this review, we provide information on the roles of both adenosine and CD73 in the immune system and tumor development. We also describe recent studies about combination therapy with both purinergic inhibitors and other immunotherapeutic methods.
Adenosine ; Immune Evasion ; Immune System ; Immunotherapy ; Metabolism ; Neoplasm Metastasis ; Tumor Microenvironment

The interactions between B7 molecules and CD28-family receptors are crucial in the regulation of adaptive cellular immunity. In cancer, the aberrant expression of co-inhibitory B7 molecules has been attributed to reduced anti-tumor immunity and cancer immune evasion, prompting the development of cancer therapeutics that can restore T cell function. Murine tumor models have provided significant support for the targeting of multiple immune checkpoints involving CTLA-4, PD-1, ICOS, B7-H3 and B7-H4 during tumor growth, and clinical studies investigating the therapeutic effects of CTLA-4 and PD-1 blockade have shown exceptionally promising results in patients with advanced melanoma and other cancers. The expression pattern of co-inhibitory B7 ligands in the tumor microenvironment has also been largely correlated with poor patient prognosis, and recent evidence suggests that the presence of several B7 molecules may predict the responsiveness of immunotherapies that rely on pre-existing tumor-associated immune responses. While monotherapies blocking T cell co-inhibition have beneficial effects in reducing tumor burden, combinatorial immunotherapy targeting multiple immune checkpoints involved in various stages of the anti-tumor response has led to the most substantial impact on tumor reduction. In this review, we will examine the contributions of B7- and CD28-family members in the context of cancer development, and discuss the implications of current human findings in cancer immunotherapy.
B7 Antigens ; Humans ; Immune Evasion ; Immunity, Cellular ; Immunotherapy* ; Ligands ; Melanoma ; Prognosis ; Tumor Burden ; Tumor Microenvironment

OBJECTIVETo investigate the role of B7-H1 expression in IL-10 production, the B7-H1 and IL-10 expression levels in pancreatic carcinoma tissues and to analyze the correlation between B7-H1 expression and IL-10 level.

METHODSThe mRNA and protein levels expressions of B7-H1 and IL-10 in 35 cases of pancreatic cancer and corresponding paracarcinoma tissues and 5 cases of normal pancreas tissues were detected by RT-PCR, Western blot and immunohistochemistry respectively.

RESULTSThe findings for the first time provided the evidences that there was a clear trend for B7-H1 and IL-10 expressions to be most highly expressed in carcinoma tissue, intermediately expressed in paracarcinoma tissue, and expressed at the lowest level in normal pancreatic tissue at mRNA and protein levels. Moreover, there were statistically significant differences in B7-H1 and IL-10 expression between pancreatic carcinoma tissues, corresponding paracarcinoma tissues and normal pancreatic tissues at mRNA and protein levels (P < 0.05). Furthermore, the immunohistochemistry indicated that there were high expression levels of B7-H1 (60.5% +/- 12.7%) and IL-10 (65.3% +/- 16.2%) in pancreatic carcinoma tissues while there were no significant expressions in normal pancreatic tissues. Meanwhile, correlation analysis revealed that B7-H1 expression was significant associated with IL-10 level in tumor tissues at mRNA (P = 0.008, r = 0.841) and protein levels (P = 0.007, r = 0.838).

CONCLUSIONSOver-expression of B7-H1 may be responsible for the increasing IL-10 production in pancreatic cancer, which caused reduced immune response to tumor cells and contributed to pancreatic carcinoma escape from immune attack.

Cancer immunoediting consists of three sequential phases: elimination, equilibrium, and escape. For colorectal adenoma-carcinoma sequence, the adenoma dysplastic progression may represent an equilibrium phase and the cancer stage as escape phase. Immune system eliminates transformed enterocytes by destroying them at first, sculpts them at the same time and selects the variants subsequently that are no longer recognized and insensitive to immune effectors, and finally induces immunosuppressive state within the tumor microenvironment that facilitates immune escape and tumor outgrowth. Immunosuppression and inflammation are the two crucial features of Pi (Spleen)-deficiency. Classic quotations, immune evidence and clinical observations suggest that Spleen (but not other organs) deficiency is the key pathogenesis of colorectal cancer (CRC) microenvironment. Weakness of old age, immunosuppressive cytokines from chronic inflammation, tumor-derived immunosuppressive factors and surrendered immune cells-regulatory T cells, myeloid-derived suppressor cells and tumor associated macrophages (TAMs) constitutes CRC microenvironment of Pi-deficiency. Furthermore, excess in superficiality, such as phlegm stagnation, blood stasis and toxin accumulation are induced by chronic inflammation on the basis of asthenia in origin, an immunosuppressive state. Great masters of Chinese medicine emphasize that strengthen Pi is the chief therapeutic principle for CRC which receives good therapeutic effects. So, Pi-deficiency based syndrome is the pivotal pathogenesis of tumor microenvironment. The immunosuppressive microenvironment facilitates immune escape which play an important role in the transition from adenoma to adenocarcinoma. There are some signs that strengthen Pi based treatment has potential capacity to ameliorate tumor environment. It might be a novel starting point to explore the mechanism of strengthen Pi based therapy in the prevention and treatment of CRC through regulation of tumor environment and immunoediting.
Colorectal Neoplasms ; immunology ; Humans ; Immune Evasion ; Immunosuppression ; Spleen ; immunology ; Syndrome ; Tumor Microenvironment ; immunology

Pseudorabies is an economically important disease in a variety ot animals caused by pseudorabies virus. Since 2011, pseudorabies outbreaks occurred in many regions of China. Related researches on this virus become a hot topic in virology and veterinary. One of the difficulties for pseudorabies prevention and control is innate immune evasion. Explorations on this issue are conducive to the development of vaccine and drugs. Therefore, this review summarized the recent research progress on the mechanisms of pseudorabies virus innate immune evasion. Theoretical direction was provided on effetive prevention and control of pseudorabies owing to this review.
Animals ; Herpesvirus 1, Suid ; genetics ; immunology ; Humans ; Immune Evasion ; Immunity, Innate ; Pseudorabies ; immunology ; virology

Head and neck squamous cell carcinoma (HNSCC), an aggressive malignancy, is characterized by high morbidity and low survival rates with limited therapeutic options outside of regional surgery, conventional cytotoxic chemotherapy, and irradiation. Increasing studies have supported the synergistic role of the tumor microenvironment (TME) in cancer advancement. The immune system, in particular, plays a key role in surveillance against the initiation, development, and progression of HNSCC. The understanding of how neoplastic cells evolve and evade the immune system whether through self-immunogenicity manipulation, or expression of immunosuppressive mediators, provides the foundation for the development of advanced therapies. Furthermore, the crosstalk between cancer cells and the host immune system have a detrimental effect on the TME promoting angiogenesis, proliferation, and metastasis. This review provides a recent insight into the role of the key inflammatory cells infiltrating the TME, with a focus on reviewing immunological principles related to HNSCC, as cancer immunosurveillance and immune escape, including a brief overview of current immunotherapeutic strategies and ongoing clinical trials.
Head and Neck Neoplasms/therapy* ; Humans ; Immune Evasion ; Squamous Cell Carcinoma of Head and Neck ; Tumor Microenvironment

OBJECTIVE: To investigate the mechanisms of anti-apoptosis and immune evasion in drug-resistant leukemia cells mediated by STAT3, further to explore the possible mechanism of leukemia relapse caused by minimal residual. METHODS: Drug-resistance leukemia cell line was established by transfecting pcDNA3.1-STAT3 into K562 cells (K562/STAT3). The expression of STAT3, BAX and NKG2D ligands (MICA and ULBP1) in K562/-cells, K562/STAT3 were detected by Western blot and/or RQ-PCR. Cells apoptosis and the killing effect of NK cells on leukemia cells were detected by flow cytometry. RESULTS: The expression of the total STAT3, STAT3 phosphorylation in K562/STAT3 was significantly increased, and P-gp mRNA expression was increased also significantly (P<0.005). In K562/STAT3 cells, the expression of pro-apoptotic BAX (P=0.005) was significantly lower, and the number of apoptotic cells (P=0.002) induced by adriamycin was significantly decreased as compared with those in K562/- cells. After K562/STAT3 cells were treated by STAT3 inhibitor (SH-4-54), the expression of BAX mRNA (P=0.017) was significantly higher and the number of apoptotic cells (P=0.005) was significantly increased. The MICA and ULBP1 mRNA expression in K562/STAT3 cells was significantly lower than that in K562/- cells, and also for MICA and ULBP1 protein (MICA and ULPB1 mRNA: P<0.0001, MICA protein: P=0.001, ULPB1 protein: P=0.022). After K562/STAT3 cells were treated with STAT3 inhibitor (SH-4-54), the expression of MICA mRNA and protein was increased (mRNA: P=0.001, protein: P=0.002), but ULBP1 mRNA and protein showed no significantly change (mRNA: P=0.137, protein: P=0.1905). The cytotoxicity of NK cells to K562/STAT3 cells was susceptible as compared with K562/- (P=0.002), but the cytotoxicity of K562/STAT3 cells to NK cell could be recovered by STAT3 inhibitor (P=0.006). CONCLUSION STAT3 phosphorylation can inhibits cell apoptosis and promotes cell immune escape. STAT3 inhibitors can promote the apoptosis of leukemia cells and increase their sensitivity to NK cells.
Apoptosis ; Humans ; Immune Evasion ; K562 Cells ; Killer Cells, Natural ; Leukemia ; Pharmaceutical Preparations ; STAT3 Transcription Factor

Since December 2019, the novel coronavirus (severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) has spread to many countries around the world, developing into a global pandemic with increasing numbers of deaths reported worldwide. To data, although some vaccines have been developed, there are no ideal drugs to treat novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)). By examining the structure of the coronavirus and briefly describing its possible pathogenesis based on recent autopsy reports conducted by various teams worldwide, this review analyzes the possible structural and functional changes of the human body upon infection with SARS-CoV-2. We observed that the most prominent pathological changes in COVID-19 patients are diffuse alveolar damage (DAD) of the lungs and microthrombus formation, resulting in an imbalance of the ventilation/perfusion ratio and respiratory failure. Although direct evidence of viral infection can also be found in other organs and tissues, the viral load is relatively small. The conclusion that the injuries of the extra-pulmonary organs are directly caused by the virus needs further investigation.
COVID-19/physiopathology* ; Human Body ; Humans ; Immune Evasion ; Lung/virology* ; Viral Load

Adult ; Aged ; Aged, 80 and over ; Bone Marrow Cells ; physiology ; Female ; Humans ; Immune Evasion ; Male ; Middle Aged ; Myelodysplastic Syndromes ; etiology ; immunology

Contagious ecthyma (also known as orf) is an acute skin zoonosis caused by orf virus (ORFV), which affects sheep, goats and humans. As one of the typical species of the Parapoxvirus genus of the Poxviridae family, orf virus has distinctive and unique characteristics of these species. A range of immuno-modulatory/pathogenesis -related genes acquired by virus that function is to limit (at least transiently) the effectiveness of host immunity during its evolution. This review is aimed to describe the latest progress on the molecular characteristics of ORFV, and upon which we analyzed molecular mechanism of the immune escape designed and a set of strategies developed for ORFV to effective against immune clearance of the host. Known as an essential component in evolutionary system, host is regulated by ORFV for using in population evolution. By the ORFV evolutional immune regulation components and its effect approach, we can understand the viral biological characteristics of ORFV, and it is helpful for us to further study the counter-measures of this disease.
Animals ; Ecthyma, Contagious ; immunology ; virology ; Gene Expression Regulation, Viral ; Immune Evasion ; Orf virus ; genetics ; immunology ; Viral Proteins ; genetics ; immunology