Faecal microbiota transplantation enhances efficacy of immune checkpoint inhibitors therapy against cancer

Even though immune checkpoint inhibitors(ICIs)are effective on multiple cancer types,there are still many non-responding patients.A possible factor put forward that may influence the efficacy of ICIs is the gut microbiota.Additionally,faecal microbiota transplantation may enhance efficacy of ICIs.Nevertheless,the data available in this field are insufficient,and relevant scientific work has just commenced.As a result,the current work reviewed the latest research on the association of gut microbiota with ICI treatments based on anti-programmed cell death protein 1 antibody and anti-cytotoxic T-lymphocyte-associated protein 4 antibody and explored the therapeutic potential of faecal microbiota transplantation in combination with ICI therapy in the future.

Immunotherapies for well-differentiated grade 3 gastroenteropancreatic neuroendocrine tumors:A new category in the World Health Organization classification

According to the 2019 World Health Organization(WHO)classification,welldifferentiated grade 3(G3)gastroenteropancreatic(GEP)neuroendocrine tumors(NETs)are a new category of cancer of the digestive system.G3 GEP-NET research and treatment are not as robust as those of lower grade(G1/2)NETs and poorly differentiated neuroendocrine carcinomas(NECs).Previously,the management of high-grade NETs was mainly based on NEC therapies,as highgrade NETs were classified as NECs under the previous WHO classification.Despite this,G3 GEP-NETs are significantly less responsive to platinum-based chemotherapy regimens than NECs,due to their distinct molecular pathogenesis and course of pathological grade transition.Patients with advanced G3 GEPNETs,who have progressed or are intolerant to chemotherapy regimens such as capecitabine plus temozolomide,have limited treatment choices.Immunotherapy has helped patients with a variety of cancers attain long-term survival through the use of immune checkpoint inhibitors.Immunotherapies,either alone or in combination with other therapies,do not have a clear function in the treatment of G3 GEP-NETs.Currently,the majority of immunotherapy studies,both prospective and retrospective,do not reliably differentiate G3 GEP-NETs from NECs.By contrast,a significant number of studies include non-GEP neuroendocrine neoplasms(NENs).Therefore,there is an urgent need to summarize and evaluate these data to provide more effective therapeutic approaches for patients with this rare tumor.The purpose of this mini-review was to screen and summarize information on G3 GEP-NETs from all studies on NENs immunotherapy.

Why natural killer cells in triple negative breast cancer?

The triple-negative subtype of breast cancer(TNBC)has the bleakest prognosis,owing to its lack of either hormone receptor as well as human epidermal growth factor receptor 2.Henceforth,immunotherapy has emerged as the front-runner for TNBC treatment,which avoids potentially damaging chemotherapeutics.However,despite its documented association with aggressive side effects and developed resistance,immune checkpoint blockade continues to dominate the TNBC immunotherapy scene.These immune checkpoint blockade drawbacks necessitate the exploration of other immunotherapeutic methods that would expand options for TNBC patients.One such method is the exploitation and recruitment of natural killer cells,which by harnessing the innate rather than adaptive immune system could potentially circumvent the downsides of immune checkpoint blockade.In this review,the authors will elucidate the advantageousness of natural killer cell-based immuno-oncology in TNBC as well as demonstrate the need to more extensively research such therapies in the future.

Expression of E2A in Mid-secretory Endometrium of Women Suffering from Recurrent Miscarriage

E2A is involved in promoting forkhead box P3（FOXP3） and retinoid-related orphan receptor gamma t（RORγt） gene transcription, which are pivotal transcription factors of T regulatory cells and Th17 cells, respectively. Little is known about the involvement of E2 A in pregnancy process. This study aimed to investigate the expression of E2 A, cytotoxic T-lymphocyte-associated protein 4（CTLA-4）, and Foxp3 in luteal phase endometrium of women suffering recurrent miscarriage（RM）（n=21） and control group（n=11） by immunohistochemistry, with the Vectra？ automated quantitative pathology imaging system for analysis. The percentage of E2 A＋ cells and CTLA-4＋ cells was significantly higher in the endometrium of women with RM than in the controls. There was positive correlation between E2 A and CTLA-4（r=0.523, P=0.002）, E2 A and FOXP3（r=0.380, P=0.032）, and FOXP3 and CTLA-4（r=0.625, P=0.000） in the mid-secretory phase of endometrium for all subjects. It was concluded that the abnormal expression of endometrial E2 A existed in mid-secretory endometrium of women with RM, and there was a positive correlation between E2 A and FOXP3, and E2 A and CTLA-4, suggesting the possible regulation role of E2 A involved in regulating endometrium receptivity.

Blood and Histopathological Biomarkers of Immune-related Adverse Effects of Treatment with Immune Checkpoint Inhibitors

Immune checkpoint inhibitors have been a recent major breakthrough in the management of tumors.They have broadened the scope of management in medical oncology,which has been heavily dependent on chemotherapy.Immune checkpoint inhibitors have renewed the hope of many patients for a more effective treatment.However,Immune checkpoint inhibitors are also associated with a variety of adverse effects,most commonly immunerelated adverse events,and these are often different from the known chemotherapy-induced toxicities.Hence,there is a need to identify specific biomarkers which are able to predict or diagnose these immune-related adverse events.

Bioengineering bacterial encapsulin nanocompartments as targeted drug delivery system

The development of Drug Delivery Systems(DDS)has led to increasingly efficient therapies for the treatment and detection of various diseases.DDS use a range of nanoscale delivery platforms produced from polymeric of inorganic materials,such as micelles,and metal and polymeric nanoparticles,but their variant chemical composition make alterations to their size,shape,or structures inherently complex.Genetically encoded protein nanocages are highly promising DDS candidates because of their modular composition,ease of recombinant production in a range of hosts,control over assembly and loading of cargo molecules and biodegradability.One example of naturally occurring nanocompartments are encapsulins,recently discovered bacterial organelles that have been shown to be reprogrammable as nanobioreactors and vaccine candidates.Here we report the design and application of a targeted DDS platform based on the Thermotoga maritima encapsulin reprogrammed to display an antibody mimic protein called Designed Ankyrin repeat protein(DARPin)on the outer surface and to encapsulate a cytotoxic payload.The DARPin9.29 chosen in this study specifically binds to human epidermal growth factor receptor 2(HER2)on breast cancer cells,as demonstrated in an in vitro cell culture model.The encapsulin-based DDS is assembled in one step in vivo by co-expressing the encapsulin-DARPin9.29 fusion protein with an engineered flavin-binding protein mini-singlet oxygen generator(MiniSOG),from a single plasmid in Escherichia coli.Purified encapsulin-DARPin_miniSOG nanocompartments bind specifically to HER2 positive breast cancer cells and trigger apoptosis,indicating that the system is functional and specific.The DDS is modular and has the potential to form the basis of a multi-receptor targeted system by utilising the DARPin screening libraries,allowing use of new DARPins of known specificities,and through the proven flexibility of the encapsulin cargo loading mechanism,allowing selection of cargo proteins of choice.

Up-regulation of indoleamine 2,3-dioxygenase 1(IDO1)expression and catalytic activity is associated with immunosuppression and poor prognosis in penile squamous cell carcinoma patients

Background: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp)catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of IDO1 in penilesquamous cell carcinoma (PSCC) and explored their clinical significance.Methods: IDO1 expression level, serum concentrations of Trp and kynurenine (Kyn)were examined in 114 PSCC patients by immunohistonchemistry and solid-phaseextraction-liquid chromatography-tandem mass spectrometry. The survival was analyzed using Kaplan-Meier method and the log-rank test. Hazard ratio of death was analyzed via univariate and multivariate Cox regression. Immune cell types were definedby principal component analysis. The correlativity was assessed by Pearson’s correlation analysis.Results: The expression level of IDO1 in PSCC cells was positively correlatedwith serum Kyn concentration and Kyn/Trp radio (KTR;both P < 0.001) but negatively correlated with serum Trp concentration (P = 0.001). Additionally, IDO1 upregulation in cancer cells and the increase of serum KTR were significantly associated with advanced N stage (both P < 0.001) and high pathologic grade (P = 0.008and 0.032, respectively). High expression level of IDO1 in cancer cells and serumKTR were associated with short disease-specific survival (both P < 0.001). However, besides N stage (hazard radio [HR], 6.926;95% confidence interval [CI],2.458-19.068;P < 0.001) and pathologic grade (HR, 2.194;95% CI, 1.021-4.529;P = 0.038), only serum KTR (HR, 2.780;95% CI, 1.066-7.215;P = 0.036) was anindependent predictor for PSCC prognosis. IDO1 expression was positively correlated with the expression of interferon-𝛾 (IFN𝛾, P < 0.001) and immunosuppressivemarkers (programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4 and programmed death-ligand 1 and 2;all P < 0.05), and the infiltration ofimmune cells (including cytotoxic T lymphocytes, regulatory T lymphocytes, tumorassociated macrophages, and myeloid-derived suppressor cells;all P < 0.001) inPSCC tissues. Furthermore, the expression of IDO1 was induced by IFN𝛾 in a dosedependent manner in PSCC cells.Conclusions: IFN𝛾-induced IDO1 plays a crucial role in immunoediting andimmunosuppression in PSCC. Additionally, serum KTR, an indicator of IDO1catabolic activity, can be utilized as an independent prognostic factor for PSCC.

Immune checkpoint:The novel target for antitumor therapy

Inhibitory checkpoint molecules include programmed cell death-1(PD-1),programmed cell death ligand-1(PD-L1),cytotoxic T lymphocyte antigen-4(CTLA-4),human endogenous retrovirus-H Long terminal repeat-associating 2(HHLA2),B7 homolog 4 protein(B7-H4),T cell membrane protein-3(TIM-3)and Lymphocyte-activation gene 3(LAG-3),which are up-regulated during tumorigenesis.These pathways are essential to down-regulate the immune system by blocking the activation of T cells.In recent years,immune checkpoint blockers(ICBs)against PD-1,PD-L1,CTLA-4 or TIM-3 has made remarkable progress in the clinical application,revolutionizing the treatment of malignant tumors and improving patients’overall survival.However,the efficacy of ICBs in some patients does not seem to be good enough,and more immune-related adverse events(irAEs)will inevitably occur.Therefore,biomarkers research provides practical guidance for clinicians to identify patients who are most likely to benefit from or exhibit resistance to particular types of immune checkpoint therapy.There are two points in general.On the one hand,given the spatial and temporal differential expression of immune checkpoint molecules during immunosuppression process,it is essential to understand their mechanisms to design the most effective individualized therapy.On the other hand,due to the lack of potent immune checkpoints,it is necessary to combine them with novel biomarkers(such as exosomes and ctDNA)and other anticancer modalities(such as chemotherapy and radiotherapy).