IL-2 regulates tumor-reactive CD8+ T cell exhaustion by activating the aryl hydrocarbon receptor.

CD8+ T cell exhaustion dampens antitumor immunity. Although several transcription factors have been identified that regulate T cell exhaustion, the molecular mechanisms by which CD8+ T cells are triggered to enter an exhausted state remain unclear. Here, we show that interleukin-2 (IL-2) acts as an environmental cue to induce CD8+ T cell exhaustion within tumor microenvironments. We find that a continuously high level of IL-2 leads to the persistent activation of STAT5 in CD8+ T cells, which in turn induces strong expression of tryptophan hydroxylase 1, thus catalyzing the conversion to tryptophan to 5-hydroxytryptophan (5-HTP). 5-HTP subsequently activates AhR nuclear translocation, causing a coordinated upregulation of inhibitory receptors and downregulation of cytokine and effector-molecule production, thereby rendering T cells dysfunctional in the tumor microenvironment. This molecular pathway is not only present in mouse tumor models but is also observed in people with cancer, identifying IL-2 as a novel inducer of T cell exhaustion.

S-15 in combination of Akt inhibitor promotes the expansion of CD45RA-CCR7+ tumor infiltrating lymphocytes with high cytotoxic potential and downregulating PD-1+Tim-3+ cells as well as regulatory T cells.

BACKGROUND: Autologous tumor-infiltrating lymphocytes (Tils) immunotherapy is a promising treatment in patients with advanced hepatocellular cancer. Although Tils treatment has shown great promise, their persistence and the efficacy after adoptive-transfer are insufficient and remain a challenge. Studies have demonstrated that IL-15 and Akt inhibitor can regulate T cell differentiation and memory. Here, we constructed S-15 (Super human IL-15), a fusion protein consisting of human IL-15, the sushi domain of the IL-15 receptor α chain and human IgG-Fc. Herein we compared the effects of S-15 with IL-2 or in combination with Akti on the expansion and activation of Tils. METHODS: Hepatocellular cancer tissues were obtained from 6 patients, Tils were expanded using IL-2, IL-2/S-15, IL-2/Akti or in combination IL-2/S-15/Akti. At day 10, anti-CD3 antibody was added to the culture media and expanded to day 25. The composition, exhaustion and T-cell differentiation markers (CD45RA/CCR7) were analyzed by flow cytometry. RESULTS: We found that IL-2/S-15/Akti expanded Tils and showed the highest percentage of central memory CD45RA-CCR7+ phenotype prior to anti-CD3 antibody activation and after anti-CD3 antibody activation. T cells cultured with IL-2/S-15/Akti exhibited a mixture of CD4+, CD8+, and CD3+CD4-CD8- T cells; S-15 in combination with Akt inhibitor downregulated the expression of PD-1+Tim-3+ on Tils and decreased the Tregs in Tils. Additionally, the Tils expanded in the presence of the Akt inhibitor and S-15 showed enhanced antitumor activity as indicated by the increase in IFN-γ producing tumor infiltrating CD8+ T cells and without comprising the Tils expansion. CONCLUSION: Our study elucidates that IL-2/S-15/Akti expanded Tils and represent a viable source for the cellular therapy for patients with hepatocellular cancer.

Sulforaphene induces apoptosis and inhibits the invasion of esophageal cancer cells through MSK2/CREB/Bcl-2 and cadherin pathway in vivo and in vitro.

BACKGROUND: As a novel type of isothiocyanate derived from radish seeds from cruciferous vegetables, sulforaphene (SFE, 4-methylsufinyl-3-butenyl isothiocyanate) has various important biological effects, such as anti-oxidative and anti-bacterial effects. Recently, sulforaphene has attracted increasing attention for its anti-tumor effects and its ability to suppress the development of multiple tumors through different regulatory mechanisms. However, it has not yet been widely investigated for the treatment of esophageal cancer. METHODS: We observed an increased apoptosis in esophageal cancer cells on sulforaphene treatment through flow cytometry (FCM) analysis and transmission electron microscopy (TEM). Through mass spectrometry (MS) analysis, we further detected global changes in the proteomes and phosphoproteomes of esophageal cancer cells on sulforaphene treatment. The molecular mechanism of sulforaphene was verified by western blot,the effect and mechanism of SFE on esophageal cancer was further verified by patient-derived xenograft mouse model. RESULTS: We identified multiple cellular processes that were changed after sulforaphene treatment by proteomics. We found that sulforaphene could repress the phosphorylation of CREB through MSK2, leading to suppression of Bcl-2 and further promoted cell apoptosis. Additionally, we confirmed that sulforaphene induces tumor cell apoptosis in mice. Interestingly, we also observed the obvious inhibition of cell migration and invasion caused by sulforaphene treatment by inhibiting the expression of cadherin, indicating the complex effects of sulforaphene on the development of esophageal cancer. CONCLUSIONS: Our data demonstrated that sulforaphene induced cell apoptosis and inhibits the invasion of esophageal cancer through a mechanism involving the inhibition of the MSK2-CREB-Bcl2 and cadherin pathway. Sulforaphene could therefore serve as a promising anti-tumor drug for the treatment of esophageal cancer.

The retinoic acid derivative, ABPN, inhibits pancreatic cancer through induction of Nrdp1.

Combination chemotherapy for the treatment of pancreatic cancer commonly employs gemcitabine with an EGFR inhibitor such as erlotinib. Here, we show that the retinoic acid derivative, ABPN, exhibits more potent anticancer effects than erlotinib, while exhibiting less toxicity toward noncancerous human control cells. Low micromolar concentrations of ABPN induced apoptosis in BxPC3 and HPAC pancreatic cancer cell lines, concomitant with a reduction in phosphorylated EGFR as well as decreased ErbB3, Met and BRUCE protein levels. The degradation of ErbB3 is a result of proteasomal degradation, possibly due to the ABPN-dependent upregulation of Nrdp1. Administration of ABPN showed significant reductions in tumor size when tested using a mouse xenograft model, with higher potency than erlotinib at the same concentration. Analysis of the tumors demonstrated that ABPN treatment suppressed ErbB3 and Met and induced Nrdp1 in vivo. The data suggest that ABPN may be more suitable in combination chemotherapy with gemcitabine than the more widely used EGFR inhibitor, erlotinib.

Comprehensive multi-omics analysis of resectable locally advanced gastric cancer: Assessing response to neoadjuvant camrelizumab and chemotherapy in a single-center, open-label, single-arm phase II trial.

BACKGROUND: The current standard of care for locally advanced gastric cancer (GC) involves neoadjuvant chemotherapy followed by radical surgery. Recently, neoadjuvant treatment for this condition has involved the exploration of immunotherapy plus chemotherapy as a potential approach. However, the efficacy remains uncertain. METHODS: A single-arm, phase 2 study was conducted to evaluate the efficacy and tolerability of neoadjuvant camrelizumab combined with mFOLFOX6 and identify potential biomarkers of response through multi-omics analysis in patients with resectable locally advanced GC. The primary endpoint was the pathological complete response (pCR) rate. Secondary endpoints included the R0 rate, near pCR rate, progression-free survival (PFS), disease-free survival (DFS), and overall survival (OS). Multi-omics analysis was assessed by whole-exome sequencing, transcriptome sequencing, and multiplex immunofluorescence (mIF) using biopsies pre- and post-neoadjuvant therapy. RESULTS: This study involved 60 patients, of which 55 underwent gastrectomy. Among these, five (9.1%) attained a pathological complete response (pCR), and 11 (20.0%) reached near pCR. No unexpected treatment-emergent adverse events or perioperative mortality were observed, and the regimen presented a manageable safety profile. Molecular changes identified through multi-omics analysis correlated with treatment response, highlighting associations between HER2-positive and CTNNB1 mutations with treatment sensitivity and a favourable prognosis. This finding was further supported by immune cell infiltration analysis and mIF. Expression data uncovered a risk model with four genes (RALYL, SCGN, CCKBR, NTS) linked to poor response. Additionally, post-treatment infiltration of CD8+ T lymphocytes positively correlates with pathological response. CONCLUSION: The findings suggest the combination of PD-1-inhibitor and mFOLFOX6 showed efficacy and acceptable toxicity for locally advanced GC. Extended follow-up is required to determine the duration of the response. This study lays essential groundwork for developing precise neoadjuvant regimens.

Sulforaphene suppresses oesophageal cancer growth through mitogen- and stress-activated kinase 2 in a PDX mouse model.

BACKGROUND: Although sulforaphene has potential anticancer effects, little is known about its effect on oesophageal squamous cell carcinoma (ESCC) invasiveness. METHODS: To investigate whether sulforaphene inhibits the growth of oesophageal cancer cells, MTT and anchorage-independent cell growth assays were performed. Global changes in the proteome and phosphoproteome of oesophageal cancer cells after sulforaphene treatment were analysed by mass spectrometry (MS), and the underlying molecular mechanism was further verified by in vivo and in vitro experiments. RESULTS: Sulforaphene treatment markedly affected proteins that regulate several cellular processes in oesophageal cancer cells, and mitogen- and stress-activated kinase 2 (MSK2) was the main genetic target of sulforaphene in reducing the growth of oesophageal cancer cells. Sulforaphene significantly suppressed ESCC cell proliferation in vitro and reduced the tumour size in an oesophageal patient-derived xenograft (PDX) SCID mouse model. Furthermore, the binding of sulforaphane to MSK2 in vitro was verified using a cellular thermal dhift assay, and the effect of MSK2 knockdown on the ESCC phenotype was observed using a shMSK2 model. CONCLUSION: The results showed that sulforaphene suppresses ESCC growth in both human oesophageal squamous cells and PDX mouse model by inhibiting MSK2 expression, implicating sulforaphene as a promising candidate for ESCC treatment.

PGC-1α promotes colorectal carcinoma metastasis through regulating ABCA1 transcription.

Colorectal cancer (CRC) is a highly aggressive cancer in which metastasis plays a key role. However, the mechanisms underlying metastasis have not been fully elucidated. Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a regulator of mitochondrial function, has been reported as a complicated factor in cancer. In this study, we found that PGC-1α was highly expressed in CRC tissues and was positively correlated with lymph node and liver metastasis. Subsequently, PGC-1α knockdown was shown to inhibit CRC growth and metastasis in both in vitro and in vivo studies. Transcriptomic analysis revealed that PGC-1α regulated ATP-binding cassette transporter 1 (ABCA1) mediated cholesterol efflux. Mechanistically, PGC-1α interacted with YY1 to promote ABCA1 transcription, resulting in cholesterol efflux, which subsequently promoted CRC metastasis through epithelial-to-mesenchymal transition (EMT). In addition, the study identified the natural compound isoliquiritigenin (ISL) as an inhibitor that targeted ABCA1 and significantly reduced CRC metastasis induced by PGC-1α. Overall, this study sheds light on how PGC-1α promotes CRC metastasis by regulating ABCA1-mediated cholesterol efflux, providing a basis for further research to inhibit CRC metastasis.

Repurposing pentamidine for cancer immunotherapy by targeting the PD1/PD-L1 immune checkpoint.

Immunotherapy has emerged as an effective therapeutic approach to several cancer types. The reinvigoration of tumor-infiltrating lymphocyte-mediated immune responses via the blockade of immune checkpoint markers, such as program cell death-1 (PD-1) or its cognate ligand PD-L1, has been the basis for developing clinically effective anticancer therapies. We identified pentamidine, an FDA-approved antimicrobial agent, as a small-molecule antagonist of PD-L1. Pentamidine enhanced T-cell-mediated cytotoxicity against various cancer cells in vitro by increasing the secretion of IFN-γ, TNF-α, perforin, and granzyme B in the culture medium. Pentamidine promoted T-cell activation by blocking the PD-1/PD-L1 interaction. In vivo administration of pentamidine attenuated the tumor growth and prolonged the survival of tumor-bearing mice in PD-L1 humanized murine tumor cell allograft models. Histological analysis of tumor tissues showed an increased number of tumor-infiltrating lymphocytes in tissues derived from pentamidine-treated mice. In summary, our study suggests that pentamidine holds the potential to be repurposed as a novel PD-L1 antagonist that may overcome the limitations of monoclonal antibody therapy and can emerge as a small molecule cancer immunotherapy.

Predictive value of tumor-infiltrating lymphocytes detected by flow cytometry in colorectal cancer.

The high heterogeneity of tumor cells and the surrounding immune microenvironment affects the response to treatment in colorectal cancer (CRC) patients. Therefore, there is a need to identify new immune biomarkers to predict the treatment efficacy of CRC. This study aimed to explore the predictive value of tumor-infiltrating lymphocytes (TIL) for survival in CRC patients. Flow cytometry and gated analysis were performed to measure the TILs in tissue samples obtained from 536 CRC patients. The COX regression analysis showed that the CD8 + CD279+ cells had the highest impact of all evaluated TILs on postoperative disease-free survival (DFS) (P < 0.05). The optimal CD8 + CD279+ cutoff point for the prediction of survival was 12.2%. The Kaplan-Meier analysis showed significantly higher DFS in the high CD8 + CD279+ group compared with the low CD8 + CD279+ group (P < 0.05). CD8 + CD279+ cells were associated with DFS in CRC patients with the KARS mutation, MSI/MMR, perineural invasion, and those treated with neoadjuvant chemotherapy and other chemotherapeutic treatments (P < 0.05). After the multivariate adjustment, the expression of CD8 + CD279+ remained an independent risk factor for DFS. Overall, the CD8 + CD279+ cells were identified as an independent prognostic factor in CRC patients and could be used as a potential marker for postoperative DFS.

Oxethazaine inhibits esophageal squamous cell carcinoma proliferation and metastasis by targeting aurora kinase A.

Esophageal squamous cell carcinoma (ESCC), a malignant neoplasm with high incidence, is a severe global public health threat. The current modalities used for treating ESCC include surgery, chemotherapy, and radiotherapy. Although ESCC management and treatment strategies have improved over the last decade, the overall 5-year survival rate remains <20%. Therefore, the identification of novel therapeutic strategies that can increase ESCC patient survival rates is urgently needed. Oxethazaine, an amino-amide anesthetic agent, is mainly prescribed in combination with antacids to relieve esophagitis, dyspepsia, and other gastric disorders. In the present study, we found that oxethazaine inhibited the proliferation and migration of esophageal cancer cells. According to the results of in vitro screening and binding assays, oxethazaine binds directly to AURKA, suppresses AURKA activity, and inhibits the downstream effectors of AURKA. Notably, we found that oxethazaine suppressed tumor growth in three patient-derived esophageal xenograft mouse models and tumor metastasis in vivo. Our findings suggest that oxethazaine can inhibit ESCC proliferation and metastasis in vitro and in vivo by targeting AURKA.

A novel lncRNA MTAR1 promotes cancer development through IGF2BPs mediated post-transcriptional regulation of c-MYC.

Abnormal translation of the MYC proto-oncogene is a hallmark of the initiation and maintenance of tumorigenesis. However, the molecular mechanism underlying increased MYC protein levels in certain cancer types without a corresponding increase in MYC mRNA levels is unclear. Here, we identified a novel lncRNA, MTAR1, which is critical for post-transcriptional regulation of MYC-induced tumorigenesis. MTAR1 is essential for recruiting IGF2BPs into PABP1-mediated liquid-liquid phase separation (LLPS) complexes and facilitates IGF2BPs-mediated MYC mRNA translation. MTAR1 enhanced binding between IGF2BPs and PABP1, thereby promoting MYC mRNA stability and increased MYC mRNA translation. In summary, MTAR1 is a novel MYC-related lncRNA that contributes to tumor progression by enhancing MYC translation through mediating PABP1/IGF2BPs liquid-liquid phase separation.

A high interferon gamma signature of CD8+ T cells predicts response to neoadjuvant immunotherapy plus chemotherapy in gastric cancer.

Background: While the tumor microenvironment (TME) affects immune checkpoint blockade (ICB) efficacy, ICB also reshapes the characteristics of TME. Thus far, studies have focused on the TME evolution during neoadjuvant or adjuvant ICB therapy in gastric cancer (GC). However, the interaction between TME characteristics and neoadjuvant immunotherapy plus chemotherapy remains to be elucidated. Methods: We performed single-cell RNA sequencing on ten GC specimens pre- and post-neoadjuvant camrelizumab plus mFOLFOX6 to determine the impact of the TME on the efficacy of the combination therapy and the remodeling of TME by the therapy. Results: A high baseline interferon gamma (IFN-γ) signature in CD8+ T cells predicts better responses to the combination therapy. We also observed that the IFN-γ signature significantly decreased in multiple cell types, and the exhausted signature of CD8+ T cells was significantly suppressed during the neoadjuvant therapy. Conclusions: Our data reveal interactions between the TME and neoadjuvant immunotherapy plus chemotherapy in GC. Importantly, it also highlights the signature of CD8+ T cells in predicting response to the combination therapy in GC.

In vivo growth of subclones derived from Lewis lung carcinoma is determined by the tumor microenvironment.

Heterogeneity is a fundamental feature of human tumors and plays a major role in drug resistance and disease progression. In the present study, we selected single-cell-derived cell lines (SCDCLs) derived from Lewis lung carcinoma (LLC1) cells to investigate tumorigenesis and heterogeneity. SCDCLs were generated using limiting dilution. Five SCDCLs were subcutaneously injected into wild-type C57BL/6N mice; however, they displayed significant differences in tumor growth. Subclone SCC1 grew the fastest in vivo, whereas it grew slower in vitro. The growth pattern of SCC2 was the opposite to that of SCC1. Genetic differences in these two subclones showed marked differences in cell adhesion and proliferation. Pathway enrichment results indicate that signal transduction and immune system responses were the most significantly altered functional categories in SCC2 cells compared to those in SCC1 cells in vitro. The number and activation of CD3+ and CD8+ T cells and NK cells in the tumor tissue of tumor-bearing mice inoculated with SCC2 were significantly higher, whereas those of myeloid cells were significantly lower, than those in the SCC1 and LLC1 groups. Our results suggest that the in vivo growth of two subclones derived from LLC1 was determined by the tumor microenvironment rather than their intrinsic proliferative cell characteristics.

Xanthine oxidoreductase promotes the progression of colitis-associated colorectal cancer by causing DNA damage and mediating macrophage M1 polarization.

In addition to its pivotal role in purine metabolism, xanthine oxidoreductase (XOR) is one of the key enzymes involved in superoxide radical generation. Oxidative stress has been implicated in the etiology of colorectal cancer, but the contribution of XOR remains unclear. Here we investigated the role of XOR in colitis-associated colorectal cancer (CAC) and the underlying mechanisms. Using clinical samples, we demonstrated that XOR up-regulation was an early event in colonic carcinogenesis. Pharmacological inhibition of XOR effectively delayed the progression of CAC. Moreover, XOR activity positively correlated with tumor necrosis factor-alpha (TNFα) protein levels. Mechanistically, TNFα may activate XOR transcription via activator protein-1 and, thus, promote endogenous hydrogen peroxide generation, resulting in oxidative DNA damage in colon cancer cells. On the other hand, XOR may regulate the TNFα mRNA transcripts by mediating LPS-induced macrophage M1 polarization. Collectively, XOR promotes tumor development by programming the tumor microenvironment and stimulates CAC progression via DNA damage-induced genetic instability.

Simultaneous delivery of anti-miRNA and docetaxel with supramolecular self-assembled "chitosome" for improving chemosensitivity of triple negative breast cancer cells.

At present, treating of triple negative breast cancer (TNBC) mainly depends on chemotherapy with more toxic side effects, but the effect is limited and it is highly prone to drug resistance. Gene therapy using anti-microRNAs maybe one of alternative therapeutic strategies. Due to the poor cell permeability and significant in vivo decomposition rate of anti-microRNAs, which limits their clinical application, we developed a core-shell supramolecular nanovector of "chitosome" that were self-assembled from the synthetic amphiphilic chitosan derivatives. The constructed chitosomes could co-load hydrophilic anti-miR-21 and hydrophobic docetaxel (DTX) into one combo nanocarrier with entrapment efficiency of more than 80%, as well as spherical morphology and average particle size of 90 nm. In comparison with the naked ones, anti-miR-21 encapsulated with chitosomes showed significantly increased cellular transfection and stability against degradation by nuclease in serum. Compared with DTX or anti-miR-21 formulations used alone, the co-delivery of the two drugs with the combo chitosome obtained improved chemosensitivity of TNBC cells to DTX treatment through their synergistic mechanisms. Taken together, the developed chitosome could be a promising candidate for simultaneous delivery of insoluble chemotherapeutic drugs and gene agents for TNBC therapy. Graphical abstract.

[Correlation analysis of one-year postoperative mortality,preoperative serum indexes and postoperative nutrition guidance in elderly hip fracture patients].

OBJECTIVE: To analyze the influence of preoperative serum nutritional indexes and postoperative nutritional guidance on 1-year mortality in elderly patients with hip fracture. METHODS: From January 2015 to December 2017, 396 elderly patients with hip fracture were included in the study, including 267 females and 129 males, aged 68 to 80(75.48±2.62) years; the course of disease was 2 to 10 (6.12±1.35) days;all patients were followed up for 1-year, and were divided into death group and survival group according to whether the patients died or not. Multivariate logistic regression model was used to analyze the influencing factors of 1 year mortality. RESULTS: Duringthe follow-up, 4 patients lost contact and were treated as shedding, among which 67 patients died and 325 patients survived. The age, male patients, patients with more than three basic diseases, American Society of Anesthesiologists grade Ⅲ-Ⅳ and patients with postoperative complications in the death group were significantly higher than those in the survival group (all P<0.05). There was no significant difference in body mass index(BMI), number of smokers, fracture type and operation type (all P>0.05). The serum albumin (ALB), prealbumin (PA), lymphocyte (LYM), lymphocyte percentage(LYM%), hemoglobin(HB), transferrin(TRF), total protein(TP) in the death group were significantly lower than those in the survival group (t=5.884, 5.826, 2.020, 5.665, 4.726, 4.935, 2.862;all P<0.05). The number of patients receiving nutritional guidance in the death group was significantly less than that in the survival group (χ2=12.597, P= 0.000). There were no significant difference on white blood cell(WBC) and red blood cell(RBC) between two groups. Multivariate logistic regression analysis showed that old age, male and not receiving significant nutritional guidance were independent risk factors for 1 year mortality of elderly patients with hip fracture (OR=1.309, 43.548, 6.032;all P<0.05);high serum ALB, PA, HB, LYM% levels and combined with two or less basic diseases were protective factors (OR=0.958, 0. 913, 0.985, 0.954, 0.832; all P<0.05). CONCLUSION: Advanced age, male and multiple underlying diseases were independent risk factors for 1-year mortality in elderly patients with hip fracture, while higher preoperative nutritional level and routine nutritional guidance were protective factors.

Feasibility of reduced-dose posttransplant cyclophosphamide and cotransplantation of peripheral blood stem cells and umbilical cord-derived mesenchymal stem cells for SAA.

Posttransplant cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis is an effective strategie for patients receiving matched sibling donor hematopoietic stem cell transplantation (MSD-HSCT) and haploidentical HSCT (haplo-HSCT). We evaluated the effectiveness and safety of reduced-dose cyclophosphamide, 20 mg/kg for 13 patients in MSD-HSCT cohort and 25 mg/kg for 22 patients in haplo-HSCT cohort, on days + 3, + 4 combined with cotransplantation of peripheral blood stem cells (PBSCs) and human umbilical cord-derived mesenchymal stem cells (UC-MSCs) for severe aplastic anemia (SAA). In MSD-PTCy cohort, the times to neutrophil and platelet engraftment were significantly shorter than those in the MSD-control cohort (P < 0.05). The cumulative incidence of acute GVHD (aGVHD) at day + 100 (15.4%) was lower than that in the MSD-control cohort (P = 0.050). No patient developed chronic GVHD (cGVHD). The 1-year overall survival (OS) and event-free survival (EFS) rates were 100% and 92.3%. In haplo-PTCy cohort, the times to neutrophil and platelet engraftment were significantly shorter than those in the haplo-control cohort (P < 0.05). The cumulative incidences of aGVHD at day + 100 and 1-year cGVHD were 31.8% and 18.2%, and the 1-year OS and EFS rates were 81.8% and 66.9%. Reduced-dose PTCy and cotransplantation of PBSCs and UC-MSCs is an acceptable alternative to patients with SAA.

A Small Molecule Antagonist of PD-1/PD-L1 Interactions Acts as an Immune Checkpoint Inhibitor for NSCLC and Melanoma Immunotherapy.

Immune checkpoint inhibitors, such as monoclonal antibodies targeting programmed death 1 (PD-1) and programmed death ligand-1 (PD-L1), have achieved enormous success in the treatment of several cancers. However, monoclonal antibodies are expensive to produce, have poor tumor penetration, and may induce autoimmune side effects, all of which limit their application. Here, we demonstrate that PDI-1 (also name PD1/PD-L1 inhibitor 1), a small molecule antagonist of PD-1/PD-L1 interactions, shows potent anti-tumor activity in vitro and in vivo and acts by relieving PD-1/PD-L1-induced T cell exhaustion. We show that PDI-1 binds with high affinity to purified human and mouse PD-1 and PD-L1 proteins and is a competitive inhibitor of human PD-1/PD-L1 binding in vitro. Incubation of ex vivo activated human T cells with PDI-1 enhanced their cytotoxicity towards human lung cancer and melanoma cells, and concomitantly increased the production of granzyme B, perforin, and inflammatory cytokines. Luciferase reporter assays showed that PDI-1 directly increases TCR-mediated activation of NFAT in a PD-1/PD-L1-dependent manner. In two syngeneic mouse tumor models, the intraperitoneal administration of PDI-1 reduced the growth of tumors derived from human PD-L1-transfected mouse lung cancer and melanoma cells; increased and decreased the abundance of tumor-infiltrating CD8+ and FoxP3+ CD4+ T cells, respectively; decreased the abundance of PD-L1-expressing tumor cells, and increased the production of inflammatory cytokines. The anti-tumor effect of PDI-1 in vivo was comparable to that of the anti-PD-L1 antibody atezolizumab. These results suggest that the small molecule inhibitors of PD-1/PD-L1 may be effective as an alternative or complementary immune checkpoint inhibitor to monoclonal antibodies.

ASPM promotes hepatocellular carcinoma progression by activating Wnt/ß-catenin signaling through antagonizing autophagy-mediated Dvl2 degradation.

Hepatocellular carcinoma (HCC) is one of the most fatal cancers worldwide. In this article, we show that expression of abnormal spindle-like microcephaly-associated protein (ASPM) is up-regulated in liver cancer samples, and this up-regulation is significantly associated with tumor aggressiveness and reduced survival times of patients. Down-regulation of ASPM expression inhibits the proliferation, invasion, migration and epithelial-to-mesenchymal transition of HCC cells in vitro and inhibits tumor formation in nude mice. ASPM interacts with disheveled-2 (Dvl2) and antagonizes autophagy-mediated Dvl2 degradation by weakening the functional interaction between Dvl2 and the lipidated form of microtubule-associated proteins 1A/1B light chain 3A (LC3II), thereby increasing Dvl2 protein abundance and leading to Wnt/ß-catenin signaling activation in HCC cells. Thus, our results define ASPM as a novel oncoprotein in HCC and indicate that disruption of the Wnt-ASPM-Dvl2-ß-catenin signaling axis might have potential clinical value.

Pyruvate kinase M2 is a marker of poor prognosis in lung adenocarcinoma but not lung squamous cell carcinoma.

BACKGROUND: To explore the pyruvate kinase M2 (PKM2) expression profile as a prognostic marker of lung adenocarcinoma (LUAD) as well as lung squamous cell carcinoma (LUSC). METHODS: Retrospective bioinformatics analysis of data from the Cancer Genome Atlas-Lung Cancer dataset and the Human Protein Atlas was performed. PKM2 mRNA expression was monitored using the Kaplan-Meier Plotter online database. GraphPad Prism 6.0 and the SPSS 19.0 software package were used for statistical analysis. RESULTS: PKM2 expression was found to be significantly higher in both LUAD and LUSC than in normal controls. Although increased PKM2 expression in LUAD was correlated with poor overall survival (OS) [hazard ratio (HR): 2.128; 95% CI: 1.754-3.653; P<0.001], recurrence-free survival (RFS) (HR: 1.524; 95% CI: 1.069-2.499; P=0.0237), and progression-free survival (PFS) (HR: 2.18; 95% CI: 1.58-3; P<0.001), no such associations were found in LUSC. CONCLUSIONS: PKM2 is a potential prognostic biomarker for LUAD but not for LUSC.