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Background. Radioimmunotherapy has become one of the most promising strategies for cancer treatment. Preclinical and clinical studies have demonstrated that antiangiogenic therapy can improve the efficacy of immunotherapy and sensitize radiotherapy through a variety of mechanisms. However, it is undefined whether angiogenesis inhibitors can enhance the effect of radioimmunotherapy. In this study, we aim to explore the role of anlotinib (AL3818) on the combination of radiotherapy and immune checkpoint inhibitors in Lewis lung carcinoma mouse. Methods. C57BL/6 mouse subcutaneous tumor model was used to evaluate the ability of different treatment regimens in tumor growth control. Immune response and immunophenotyping including the quantification and activation were determined by flow cytometry, multiplex immunofluorescence, and multiplex immunoassay. Results. Triple therapy (radiotherapy combined with anti-PD-L1 and anlotinib) increased tumor-infiltrating lymphocytes and reversed the immunosuppressive effect of radiation on the tumor microenvironment in mouse model. Compared with radioimmunotherapy, the addition of anlotinib also boosted the infiltration of CD8+ T cells and M1 cells and caused a decrease in the number of MDSCs and M2 cells in mice. The levels of IFN-gamma and IL-18 were the highest in the triple therapy group, while the levels of IL-23, IL-13, IL-1 beta, IL-2, IL-6, IL-10, and Arg-1 were significantly reduced. NF-κB, MAPK, and AKT pathways were downregulated in triple therapy compared with radioimmunotherapy. Thus, the tumor immune microenvironment was significantly improved. As a consequence, triple therapy displayed greater benefit in antitumor efficacy. Conclusion. Our findings indicate that anlotinib might be a potential synergistic treatment for radioimmunotherapy to achieve better antitumor efficacy in NSCLC patients by potentiating the tumor immune microenvironment.

The 1858C>T allele of the tyrosine phosphatase PTPN22 (causing amino acid substitution R620W in encoded protein lymphoid tyrosine phosphatase) is present in 5–10% of the North American population and is strongly associated with numerous autoimmune diseases. Although much research has been done to define how this allele potentiates autoimmunity, the influence PTPN22 and its proautoimmune allele have in tumor immunity is poorly defined. To interrogate the role this allele may have in the antitumor immune response, we used CRISPR/Cas9 to generate mice in which the ortholog of lymphoid tyrosine phosphatase, PEST domain–enriched protein (PEP), is mutated at position 619 to produce the relevant proautoimmune mutation (R619W). Results of this study show that mice homozygous for this alteration (PEP-619WW) resist tumor growth as compared with wild-type mice. Consistent with these results, tumors from PEP-619WW mice have more CD45 infiltrates containing more activated CD8 T cells and CD4 T cells. In addition, there are more conventional dendritic cell type 1 (cDC1) cells and fewer myeloid-derived suppressor cells in tumors from PEP-619WW mice. Interestingly, the tumor-infiltrating PEP-619WW cDC1 cells have decreased PD-L1 expression compared with cDC1 cells from PEP-wild-type mice. Taken together, our data show that the proautoimmune allele of Ptpn22 drives a strong antitumor response in innate and adaptive immune cells resulting in superior control of tumors.

Metastatic disease remains the leading cause of death in cancer and understanding the mechanisms involved in tumor progression continues to be challenging. This work investigates the role of manganese in tumor progression in an in vivo model of tumor growth. Our data revealed that manganese accumulates within primary tumors and secondary organs as manganese-rich niches. Consequences of such phenomenon were investigated, and we verified that short-term changes in manganese alter cell surface molecules syndecan-1 and β1-integrin, enhance collective cell migration and invasive behavior. Long-term increased levels of manganese do not affect cell growth and viability but enhance cell migration. We also observed that manganese is secreted from tumor cells in extracellular vesicles, rather than in soluble form. Finally, we describe exogenous glycosaminoglycans that counteract manganese effects on tumor cell behavior. In conclusion, our analyses describe manganese as a central element in tumor progression by accumulating in Mn-rich niches in vivo, as well as in vitro, affecting migration and extracellular vesicle secretion in vitro. Manganese accumulation in specific regions of the organism may not be a common ground for all cancers, nevertheless, it represents a new aspect of tumor progression that deserves special attention.

Purpose Mutation-specific T-cell response to epithelial cancers and T-cell-based immunotherapy has been successfully used to treat several human solid cancers. We aimed to investigate the anti-tumour effect of neo-antigen-reactive T(NRT) cells induced by RNA mutanome vaccine, which may serve as a feasible and effective therapeutic approach for lung cancer. Methods We predicted candidate neo-antigens according to the mutant gene analysis by sequencing the mouse Lewis cells and C57BL/6 mouse tail tissue. RNA vaccine was prepared with the neo-antigens as the template. We assessed antitumor efficacy, cytokine secretion and pathological changes after adoptive transfer of NRT cells in vitro and vivo experiments. Results We identified 10 non-synonymous somatic mutations and successfully generated NRT cells. The percentage of T-cell activation proportion was increased from 0.072% in conventional T cells to 9.96% in NRT cells. Interferon-γ secretion augmented from 17.8 to 24.2% as well. As an in vivo model, adoptive NRT cell infusion could promote active T-cell infiltration into the tumour tissue and could delay tumour progression. Conclusion NRT cells induced by RNA mutanome vaccine exert a significant anti-tumour effect in mouse lung cancer, and adoptive NRT cell therapy might be considered a feasible, effective therapeutic approach for lung cancer.

Rationale: Immune checkpoint inhibitors (ICIs) against the PD-1/PD-L1 pathway showed limited success in non-small cell lung cancer (NSCLC) patients, especially in those with activating epidermal growth factor receptor (EGFR) mutations. Elucidation of the mechanisms underlying EGFR-mediated tumor immune escape and the development of effective immune therapeutics are urgently needed. Immunoglobulin-like transcript (ILT) 4, a crucial immunosuppressive molecule initially identified in myeloid cells, is enriched in solid tumor cells and promotes the malignant behavior of NSCLC. However, the upstream regulation of ILT4 overexpression and its function in tumor immunity of NSCLC with EGFR activation remains unclear. Methods: ILT4 expression and EGFR phosphorylation in human NSCLC tissues and cell lines were analyzed using immunohistochemistry (IHC), real-time PCR, Western blotting, immunofluorescence, and flow cytometry. The molecular signaling for EGFR-regulated ILT4 expression was investigated using mRNA microarray and The Cancer Genome Atlas (TCGA) database analyses and then confirmed by Western blotting. The regulation of tumor cell proliferation and apoptosis by ILT4 was examined by CCK8 proliferation and apoptosis assays. The impact of ILT4 and PD-L1 on tumor-associated macrophage (TAM) recruitment and polarization was evaluated using Transwell migration assay, flow cytometry, enzyme linked immunosorbent assay (ELISA) and real-time PCR, while their impact on T cell survival and cytotoxicity was analyzed by CFSE proliferation assay, apoptotic assay, flow cytometry, ELISA and cytolytic assay. Tumor immunotherapy models targeting at paired Ig-like receptor B (PIR-B, an ortholog of ILT4 in mouse)/ILT4 and/or PD-L1 were established in C57BL/6 mice inoculated with stable EGFR- overexpressing Lewis lung carcinoma (LLC) cells and in humanized NSG mice inoculated with EGFR mutant, gefitinib-resistant PC9 (PC9-GR) or EGFR-overexpressing wild type H1299 cells. PIR-B and ILT4 inhibition was implemented by infection of specific knockdown lentivirus and PD-L1 was blocked using human/mouse neutralizing antibodies. The tumor growth model was established in NSG mice injected with PIR-B-downregulated LLC cells to evaluate the effect of PIR-B on tumor proliferation. The frequencies and phenotypes of macrophages and T cells in mouse spleens and blood were detected by flow cytometry while those in tumor tissues were determined by IHC and immunofluorescence. Results: We found that ILT4 expression in tumor cells was positively correlated with EGFR phosphorylation in human NSCLC tissues. Using NSCLC cell lines, we demonstrated that ILT4 was upregulated by both tyrosine kinase mutation-induced and epidermal growth factor (EGF)-dependent EGFR activation and subsequent AKT/ERK1/2 phosphorylation. Overexpressed ILT4 in EGFR-activated tumor cells induced TAM recruitment and M2-like polarization, which impaired T cell function. ILT4 also directly inhibited T cell proliferation, cytotoxicity, and IFN-γ expression and secretion. In EGFR-activated cell lines in vitro and in wild-type EGFR-activated C57BL/6 and humanized NSG immunotherapy models in vivo, either ILT4 (PIR-B) or PD-L1 inhibition enhanced anti-tumor immunity and suppressed tumor progression by counteracting TAM- and dysfunctional T cell- induced immuno-suppressive TME; the combined inhibition of both molecules showed the most dramatic tumor retraction. Surprisingly, in EGFR mutant, TKI resistant humanized NSG immunotherapy model, ILT4 inhibition alone rather than in combination with a PD-L1 inhibitor suppressed tumor growth and immune evasion. Conclusions: ILT4 was induced by activation of EGFR-AKT and ERK1/2 signaling in NSCLC cells. Overexpressed ILT4 suppressed tumor immunity by recruiting M2-like TAMs and impairing T cell response, while ILT4 inhibition prevented immunosuppression and tumor promotion. Furthermore, ILT4 inhibition enhanced the efficacy of PD-L1 inhibitor in EGFR wild-type but not in EGFR mutant NSCLC. Our study identified novel mechanisms for EGFR-mediated tumor immune escape, and provided promising immunotherapeutic strategies for patients with EGFR-activated NSCLC.

Cancer cachexia (CC) accounts for 20%–40% of cancer-related deaths. Mitochondrial aberrations have been shown to precede muscle atrophy in different atrophy models, including cancer. Therefore, this study investigated potential protection from the cachectic phenotype through overexpression of peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α). First, to establish potential of mitochondria-based approaches we showed that the mitochondrial antioxidant MitoTEMPO (MitoT) attenuates myotube atrophy induced by Lewis lung carcinoma (LLC) cell conditioned media. Next, cachexia was induced in muscle-specific PGC-1α overexpressing (MCK-PCG1α) or wildtype (WT) littermate mice by LLC implantation. MCK-PCG1α did not protect LLC-induced muscle mass loss. In plantaris, Atrogin mRNA content was 6.2-fold and ∼11-fold greater in WT-LLC vs WT-phosphate-buffered saline (PBS) for males and females, respectively ( p

Background Cancer is associated with muscle atrophy (cancer cachexia) that is linked to up to 40% of cancer‐related deaths. Oxidative stress is a critical player in the induction and progression of age‐related loss of muscle mass and weakness (sarcopenia); however, the role of oxidative stress in cancer cachexia has not been defined. The purpose of this study was to examine if elevated oxidative stress exacerbates cancer cachexia. Methods Cu/Zn superoxide dismutase knockout (Sod1KO) mice were used as an established mouse model of elevated oxidative stress. Cancer cachexia was induced by injection of one million Lewis lung carcinoma (LLC) cells or phosphate‐buffered saline (saline) into the hind flank of female wild‐type mice or Sod1KO mice at approximately 4 months of age. The tumour developed for 3 weeks. Muscle mass, contractile function, neuromuscular junction (NMJ) fragmentation, metabolic proteins, mitochondrial function, and motor neuron function were measured in wild‐type and Sod1KO saline and tumour‐bearing mice. Data were analysed by two‐way ANOVA with Tukey–Kramer post hoc test when significant F ratios were determined and α was set at 0.05. Unless otherwise noted, results in abstract are mean ±SEM. Results Muscle mass and cross‐sectional area were significantly reduced, in tumour‐bearing mice. Metabolic enzymes were dysregulated in Sod1KO mice and cancer exacerbated this phenotype. NMJ fragmentation was exacerbated in tumour‐bearing Sod1KO mice. Myofibrillar protein degradation increased in tumour‐bearing wild‐type mice (wild‐type saline, 0.00847 ± 0.00205; wildtype LLC, 0.0211 ± 0.00184) and tumour‐bearing Sod1KO mice (Sod1KO saline, 0.0180 ± 0.00118; Sod1KO LLC, 0.0490 ± 0.00132). Muscle mitochondrial oxygen consumption was reduced in tumour‐bearing mice compared with saline‐injected wild‐type mice. Mitochondrial protein degradation increased in tumour‐bearing wild‐type mice (wild‐type saline, 0.0204 ± 0.00159; wild‐type LLC, 0.167 ± 0.00157) and tumour‐bearing Sod1KO mice (Sod1KO saline, 0.0231 ± 0.00108; Sod1 KO LLC, 0.0645 ± 0.000631). Sciatic nerve conduction velocity was decreased in tumour‐bearing wild‐type mice (wild‐type saline, 38.2 ± 0.861; wild‐type LLC, 28.8 ± 0.772). Three out of eleven of the tumour‐bearing Sod1KO mice did not survive the 3‐week period following tumour implantation. Conclusions Oxidative stress does not exacerbate cancer‐induced muscle loss; however, cancer cachexia may accelerate NMJ disruption.

Background Conventional therapeutic approaches for tumor angiogenesis, which are primarily focused on the inhibition of active angiogenesis to starve cancerous cells, target the vascular endothelial growth factor signaling pathway. This aggravates hypoxia within the tumor core and ultimately leads to increased tumor proliferation and metastasis. To overcome this limitation, we developed nanoparticles with antiseptic activity that target tumor vascular abnormalities. Methods Ferritin-based protein C nanoparticles (PCNs), known as TFG and TFMG, were generated and tested in Lewis lung carcinoma (LLC) allograft and MMTV-PyMT spontaneous breast cancer models. Immunohistochemical analysis was performed on tumor samples to evaluate the tumor vasculature. Western blot and permeability assays were used to explore the role and mechanism of the antitumor effects of PCNs in vivo. For knocking down proteins of interest, endothelial cells were transfected with siRNAs. Statistical analysis was performed using one-way ANOVA followed by post hoc Dunnett’s multiple comparison test. Results PCNs significantly inhibited hypoxia and increased pericyte coverage, leading to the inhibition of tumor growth and metastasis, while increasing survival in LLC allograft and MMTV-PyMT spontaneous breast cancer models. The coadministration of cisplatin with PCNs induced a synergistic suppression of tumor growth by improving drug delivery as evidenced by increased blood prefusion and decreased vascular permeability. Moreover, PCNs altered the immune cell profiles within the tumor by increasing cytotoxic T cells and M1-like macrophages with antitumor activity. PCNs induced PAR-1/PAR-3 heterodimerization through EPCR occupation and PAR-1 activation, which resulted in Gα13-RhoA-mediated-Tie2 activation and stabilized vascular tight junctions via the Akt-FoxO3a signaling pathway. Conclusions Cancer treatment targeting the tumor vasculature by inducing antitumor immune responses and enhancing the delivery of a chemotherapeutic agent with PCNs resulted in tumor regression and may provide an effective therapeutic strategy.

Distant metastases occur when non-small cell lung cancer (NSCLC) is at late stages. Bone metastasis is one of the most frequent metastases of NSCLC and leads to poor prognosis. It has been reported that high expression of BMP2 in NSCLC correlates with poor survival, but whether BMP2 contributes to NSCLC bone metastasis remains largely unknown. The activation of BMP signalling is found in metastatic bone tumours of mice Lewis lung carcinoma and predicts poor survival in human NSCLC. BMP2 signalling activation can enhance bone metastasis of Lewis lung carcinoma. Moreover, BMP2 secreted by stroma fibroblasts can promote the migration and invasion of NSCLC cells. Besides, in combination with pre-osteoblast and LLCs, BMP2 could enhance the differentiation of macrophages into osteoclasts to play roles in the osteolytic mechanism of NSCLC bone metastasis. Interestingly, NSCLC cells can also enrich BMP2 to pre-osteoblasts to function in the osteoblastic mechanism. Our results firstly demonstrate the detailed mechanisms about what roles BMP2 signalling play in enhancing NSCLC bone metastases. These findings provide a new potential therapy choice for preventing bone metastases of NSCLC via the inhibition of BMP2 signalling.

One of prospective methods for immunotherapy of tumors is modulation via immunological checkpoints, specifically, via the PD-1(CD279)/PD-L1(CD274) system. Interactions between tumor cell receptor (CD279) and the ligand on lymphocytes (CD274) leads to lymphocyte inactivation, which allows tumor escape from the immune control. Experiments on C57BL/6 mice with Lewis lung carcinoma demonstrate the possibility of reducing the expression of CD279 and CD274 on the peripheral blood and tumor tissue lymphocytes under the effects of Tussilago farfara L. polysaccharides. This phenomenon can underlie the antitumor and antimetastatic effects of these substances.

Background Subcutaneous mouse tumour models are widely used for the screening of novel antitumour treatments, although these models are poor surrogate models of human cancers. Methods We compared the antitumour efficacy of the combination of ionising radiation (IR) with two DNA damage response inhibitors, the PARP inhibitor olaparib and the ATR inhibitor AZD6738 (ceralasertib), in subcutaneous versus orthotopic cancer models. Results Olaparib delayed the growth of irradiated Lewis lung carcinoma (LL2) subcutaneous tumours, in agreement with previous reports in human cell lines. However, the olaparib plus IR combination showed a very narrow therapeutic window against LL2 lung orthotopic tumours, with nearly no additional antitumour effect compared with that of IR alone, and tolerability issues emerged at high doses. The addition of AZD6738 greatly enhanced the efficacy of the olaparib plus IR combination treatment against subcutaneous but not orthotopic LL2 tumours. Moreover, olaparib plus AZD6738 administration concomitant with IR even worsened the response to radiation of head and neck orthotopic tumours and induced mucositis. Conclusions These major differences in the responses to treatments between subcutaneous and orthotopic models highlight the importance of using more pathologically relevant models, such as syngeneic orthotopic models, to determine the most appropriate therapeutic approaches for translation to the clinic.

Emerging immune therapy, such as with the anti–programmed cell death–1 (anti–PD-1) monoclonal antibody nivolumab, has shown efficacy in tumor suppression. Patients with terminal cancer suffer from cancer pain as a result of bone metastasis and bone destruction, but how PD-1 blockade affects bone cancer pain remains unknown. Here, we report that mice lacking Pdcd1 (Pd1(−/−)) demonstrated remarkable protection against bone destruction induced by femoral inoculation of Lewis lung cancer cells. Compared with WT mice, Pd1(−/−) mice exhibited increased baseline pain sensitivity, but the development of bone cancer pain was compromised in Pd1(−/−) mice. Consistently, these beneficial effects in Pd1(−/−) mice were recapitulated by repeated i.v. applications of nivolumab in WT mice, even though nivolumab initially increased mechanical and thermal pain. Notably, PD-1 deficiency or nivolumab treatment inhibited osteoclastogenesis without altering tumor burden. PD-L1 and CCL2 are upregulated within the local tumor microenvironment, and PD-L1 promoted RANKL-induced osteoclastogenesis through JNK activation and CCL2 secretion. Bone cancer upregulated CCR2 in primary sensory neurons, and CCR2 antagonism effectively reduced bone cancer pain. Our findings suggest that, despite a transient increase in pain sensitivity following each treatment, anti–PD-1 immunotherapy could produce long-term benefits in preventing bone destruction and alleviating bone cancer pain by suppressing osteoclastogenesis.

Tumor-treating fields (TTFields) are alternating electric fields in a specific frequency range (100–300 kHz) delivered to the human body through transducer arrays. In this study, we evaluated whether TTFields-mediated cell death can elicit antitumoral immunity and hence would be effectively combined with anti-PD-1 therapy. We demonstrate that in TTFields-treated cancer cells, damage-associated molecular patterns including high-mobility group B1 and adenosine triphosphate are released and calreticulin is exposed on the cell surface. Moreover, we show that TTFields treatment promotes the engulfment of cancer cells by dendritic cells (DCs) and DCs maturation in vitro, as well as recruitment of immune cells in vivo. Additionally, our study demonstrates that the combination of TTFields with anti-PD-1 therapy results in a significant decline of tumor volume and increase in the percentage of tumor-infiltrating leukocytes in two tumor models. In orthotopic lung tumors, these infiltrating leukocytes, specifically macrophages and DCs, showed elevated expression of PD-L1. Compatibly, cytotoxic T-cells isolated from these tumors demonstrated increased production of IFN-γ. In colon cancer tumors, T-cells infiltration was significantly increased following long treatment duration with TTFields plus anti-PD-1. Collectively, our results suggest that TTFields therapy can induce anticancer immune response. Furthermore, we demonstrate robust efficacy of concomitant application of TTFields and anti-PD-1 therapy. These data suggest that integrating TTFields with anti-PD-1 therapy may further enhance antitumor immunity, hence achieve better tumor control. Electronic supplementary material The online version of this article (10.1007/s00262-020-02534-7) contains supplementary material, which is available to authorized users.

Near-infrared photoimmunotherapy (NIR-PIT) is a newly developed and selective cancer treatment that induces necrotic and immunogenic cell death and utilizes a monoclonal antibody conjugated to a photo-absorber dye, IR700DX, activated by NIR light. Although CD44 is surface cancer marker associated with drug resistance, anti-CD44-IR700 NIR-PIT results in inhibited cell growth and prolonged survival in multiple tumor types. Meanwhile, anti-CD25-IR700–targeted NIR-PIT has been reported to achieve selective and local depletion of FOXP3(+)CD25(+)CD4(+) regulatory T cells (Tregs), which are primary immunosuppressive cells in the tumor microenvironment (TME), resulting in activation of local antitumor immunity. Combined NIR-PIT with CD44- and CD25-targeted agents has the potential to directly eliminate tumor cells and also amplify the immune response by removing FOXP3(+)CD25(+)CD4(+) Tregs from the TME. We investigated the difference in therapeutic effects of CD44-targeted NIR-PIT alone, CD25-targeted NIR-PIT alone, and the combination of CD44- and CD25-targeted NIR-PIT in several syngeneic tumor models, including MC38-luc, LL/2, and MOC1. The combined NIR-PIT showed significant tumor growth inhibition and prolonged survival compared with CD44-targeted NIR-PIT alone in all tumor models and showed prolonged survival compared with CD25-targeted NIR-PIT alone in MC38-luc and LL/2 tumors. Combined CD44/CD25 NIR-PIT also resulted in some complete remissions, whereas this was not achieved with either type of NIR-PIT alone. Therefore, combined NIR-PIT simultaneously targeting cancer antigens and immunosuppressive cells in the TME may be more effective than either type of NIR-PIT alone and may have potential to induce prolonged immune responses in treated tumors.

We studied specific antitumor activity of a liposomal drug based on tetra-3-phenylthiophthalocyanine aluminum hydroxide (lipophthalocyan) intended for photodynamic therapy. The optimal dose and protocol for photodynamic therapy with lipophthalocyan were chosen in experiments on mice: single intravenous dose of 6 mg/kg with a 5-h interval between administration and laser exposure and irradiation energy density of 400 J/cm2. A wide spectrum antitumor activity of lipophthalocyan was demonstrated in vivo for various transplantable mouse tumors (Lewis lung epidermoid carcinoma, S37 sarcoma, and colon adenocarcinoma AKATOL). The results show the possibility of using lipophthalocyan for photodynamic therapy of tumors of surface localization (skin and mucosa tumors).

This study was conducted to determine the antitumor effects and ability of an anlotinib (AL) hydrogel (AL–HA–Tyr) to reduce toxicity in a mouse model of Lewis lung cancer (LLC). We constructed a drug carrier system for AL, verified its effectiveness and systemic safety, and provided a preliminary experimental foundation for clinical carrier transformation. AL–HA–Tyr was prepared by encapsulating AL with hyaluronic acid–tyramine (HA–Tyr) conjugates. Colony and tube formation assays showed that AL–HA–Tyr restrained the proliferation of human umbilical vein endothelial cells (HUVECs) and LLC cells, respectively, in vitro, and that AL exerted significant anti-angiogenesis and anti-tumor effects. The invasion and migration of HUVECs and LLC cells were efficiently suppressed by AL according to transwell assays. HUVEC and LLC cell-cycle and apoptosis analysis clarified the direct anti-tumor effects of AL–HA–Tyr. Mice engrafted with LLC cells in vivo were administered oral saline, oral AL, or an intratumoral injection of HA–Tyr or AL–HA–Tyr. The results showed that AL–HA–Tyr obviously reduced visceral toxicity and decreased Ki67 and VEGF-A expression in tumor cells compared with AL. Furthermore, AL–HA–Tyr significantly prolonged the survival of tumor-bearing mice. Overall, AL–HA–Tyr enhanced antitumor effects and reduced toxicity in the LLC model. It provided a foundation for the clinical transformation of drug carrier systems.

Cisplatin resistance is a major barrier in the effective treatment of lung cancer. Cisplatin-resistant (CR) lung cancer cells do not primarily use glucose but rather consume amino acids such as glutamine and tryptophan (Trp) for survival. CR cells activate the kynurenine (KYN) pathway (KP) to cope with excessive reactive oxygen species (ROS) and maintain homeostasis for growth and proliferation. Consequently, indoleamine 2,3-dioxygenase-1 (IDO1) becomes an essential enzyme for CR cells' survival because it initiates and regulates the first step in the KP. Increased IDO1 activities and ROS levels are found in CR cells versus cisplatin-sensitive lung cancer. Importantly, significantly greater KYN/Trp ratio (P = 0.005) is detected in serum of patients who fail cisplatin when compared with naïve treatment. Knocking down IDO1 using shRNA or IDO1 inhibitors heightens ROS levels and results in a significant growth inhibitory effect only on CR cells and not on cisplatin-sensitive cells. Exposing CR cells to antioxidant (TIRON) results in suppression of IDO1 activity and confers resistance to IDO1 inhibition, indicating an interrelationship between ROS and IDO1. Because KYN plays a critical role in reprogramming naïve T cells to the immune-suppressive regulatory T-cell (T-reg) phenotype, we observed higher expression of TGFβ, FoxP3, and CD4+CD25+ in mice bearing CR tumors compared with tumors from cisplatin-sensitive counterparts. Implications: Findings suggest that the enzyme-inhibitory activity and antitumor efficacy of IDO1 inhibitors rely in part on ROS levels, arguing that IDO1 expression alone may be insufficient to determine the clinical benefits for this class of experimental cancer drugs. Importantly, IDO1 inhibitors may be more suitable to treat patients with lung cancer who failed cisplatin therapy than naïve treatment patients.

Metabolic dysfunction and insulin resistance are emerging as hallmarks of cancer and cachexia, and impair cancer prognosis. Yet, the molecular mechanisms underlying impaired metabolic regulation are not fully understood. To elucidate the mechanisms behind cancer-induced insulin resistance in muscle, we isolated extensor digitorum longus (EDL) and soleus muscles from Lewis Lung Carcinoma tumor-bearing mice. Three weeks after tumor inoculation, muscles were isolated and stimulated with or without a submaximal dose of insulin (1.5 nM). Glucose transport was measured using 2-[3H]Deoxy-Glucose and intramyocellular signaling was investigated using immunoblotting. In soleus muscles from tumor-bearing mice, insulin-stimulated glucose transport was abrogated concomitantly with abolished insulin-induced TBC1D4 and GSK3 phosphorylation. In EDL, glucose transport and TBC1D4 phosphorylation were not impaired in muscles from tumor-bearing mice, while AMPK signaling was elevated. Anabolic insulin signaling via phosphorylation of the mTORC1 targets, p70S6K thr389, and ribosomal-S6 ser235, were decreased by cancer in soleus muscle while increased or unaffected in EDL. In contrast, the mTOR substrate, pULK1 ser757, was reduced in both soleus and EDL by cancer. Hence, cancer causes considerable changes in skeletal muscle insulin signaling that is dependent on muscle-type, which could contribute to metabolic dysregulation in cancer. Thus, the skeletal muscle could be a target for managing metabolic dysfunction in cancer.

Only a subpopulation of non-small cell lung cancer (NSCLC) patients responds to immunotherapies, highlighting the urgent need to develop therapeutic strategies to improve patient outcome. We develop a chemical positive modulator (HEI3090) of the purinergic P2RX7 receptor that potentiates αPD-1 treatment to effectively control the growth of lung tumors in transplantable and oncogene-induced mouse models and triggers long lasting antitumor immune responses. Mechanistically, the molecule stimulates dendritic P2RX7-expressing cells to generate IL-18 which leads to the production of IFN-γ by Natural Killer and CD4+ T cells within tumors. Combined with immune checkpoint inhibitor, the molecule induces a complete tumor regression in 80% of LLC tumor-bearing mice. Cured mice are also protected against tumor re-challenge due to a CD8-dependent protective response. Hence, combination treatment of small-molecule P2RX7 activator followed by immune checkpoint inhibitor represents a strategy that may be active against NSCLC., A limited percentage of patients with non-small cell lung cancer respond to immunotherapy. Here the authors show that HEI3090, a chemical positive modulator of the purinergic P2RX7 receptor, promotes IL-18 mediated anti-tumor immune responses and sensitizes lung cancer to anti-PD-1 therapy in preclinical models.

Although the main focus of immuno-oncology has been manipulating the adaptive immune system, tumor associated macrophages (TAMs) are the main infiltrating component in the tumor microenvironment (TME) and play a critical role in cancer progression. TAMs are mainly divided into two different subtypes: macrophages with antitumor or killing activity are called M1 while tumor-promoting or healing macrophages are named M2. Therefore, controlling the polarization of TAMs is an important strategy for cancer treatment, but there is no particularly effective means to regulate the polarization process. Here, combined systems pharmacology targets and pathways analysis strategy, we uncovered Scutellariae Radix (SR) has the potential to regulate TAMs polarization to inhibit the growth of non-small cell lung cancer (NSCLC). Firstly, systems pharmacology approach was used to reveal the active components of SR targeting macrophages in TME through compound target prediction and target-microenvironment phenotypic association analysis. Secondly, in vitro experiment verified that WBB (wogonin, baicalein and baicalin), major active ingredients of SR are significantly related to macrophages and survival, initiated macrophages programming to M1-like macrophages to promoted the apoptosis of tumor cells. Finally, we evidenced that WBB effectively inhibited tumor growth in LLC (Lewis lung carcinoma) tumor-bearing mice and increased the infiltration of M1-type macrophages in TME. Overall, the systems pharmacology strategy offers a paradigm to understand the mechanism of polypharmacology of natural products targeting TME.

Nanotechnology has emerged as a promising solution to permanent elimination of cancer. However, nanoparticles themselves lack specificity to tumors. Due to enhanced migration to tumors, mesenchymal stem cells (MSCs) were suggested as cell-mediated delivery vehicles of nanoparticles. In this study, we have constructed a complex composed of photoluminescent quantum dots (QDs) and a photosensitizer chlorin e6 (Ce6) to obtain multifunctional nanoparticles, combining cancer diagnostic and therapeutic properties. QDs serve as energy donors-excited QDs transfer energy to the attached Ce6 via Forster resonance energy transfer, which in turn generates reactive oxygen species. Here, the physicochemical properties of the QD-Ce6 complex and singlet oxygen generation were measured, and the stability in protein-rich media was evaluated, showing that the complex remains the most stable in protein-free medium. In vitro studies on MSC and cancer cell response to the QD-Ce6 complex revealed the complex-loaded MSCs' potential to transport theranostic nanoparticles and induce cancer cell death. In vivo studies proved the therapeutic efficacy, as the survival of tumor-bearing mice was statistically significantly increased, while tumor progression and metastases were slowed down.

The combination of radiotherapy (RT) with immunotherapy represents a promising treatment modality for non-small cell lung cancer (NSCLC) patients. As only a minority of patients shows a persistent response today, a spacious optimization window remains to be explored. Previously we showed that fractionated RT can induce a local immunosuppressive profile. Based on the evolving concept of an immunomodulatory role for vagal nerve stimulation (VNS), we tested its therapeutic and immunological effects alone and in combination with fractionated RT in a preclinical-translational study. Lewis lung carcinoma-bearing C57Bl/6 mice were treated with VNS, fractionated RT or the combination while a patient cohort with locally advanced NSCLC receiving concurrent radiochemotherapy (ccRTCT) was enrolled in a clinical trial to receive either sham or effective VNS daily during their 6 weeks of ccRTCT treatment. Preclinically, VNS alone or with RT showed no therapeutic effect yet VNS alone significantly enhanced the activation profile of intratumoral CD8+ T cells by upregulating their IFN-γ and CD137 expression. In the periphery, VNS reduced the RT-mediated rise of splenic, but not blood-derived, regulatory T cells (Treg) and monocytes. In accordance, the serological levels of protumoral CXCL5 next to two Treg-attracting chemokines CCL1 and CCL22 were reduced upon VNS monotherapy. In line with our preclinical findings on the lack of immunological changes in blood circulating immune cells upon VNS, immune monitoring of the peripheral blood of VNS treated NSCLC patients (n=7) did not show any significant changes compared to ccRTCT alone. As our preclinical data do suggest that VNS intensifies the stimulatory profile of the tumor infiltrated CD8+ T cells, this favors further research into non-invasive VNS to optimize current response rates to RT-immunotherapy in lung cancer patients.

Natural polysaccharides have shown promising effects on the regulation of immunity in animals. In this study, we examined the immune stimulatory effect of intranasally administered Codium fragile polysaccharides (CFPs) in mice. Intranasal administration of CFPs in C57BL/6 mice induced the upregulation of surface activation marker expression in macrophages and dendritic cells (DCs) in the mediastinal lymph node (mLN) and the production of interleukin-6 (IL-6), IL-12p70, and tumor necrosis factor-α in bronchoalveolar lavage fluid. Moreover, the number of conventional DCs (cDCs) was increased in the mLNs by the upregulation of C-C motif chemokine receptor 7 expression, and subsets of cDCs were also activated following the intranasal administration of CFP. In addition, the intranasal administration of CFPs promoted the activation of natural killer (NK) and T cells in the mLNs, which produce pro-inflammatory cytokines and cytotoxic mediators. Finally, daily administration of CFPs inhibited the infiltration of Lewis lung carcinoma cells into the lungs, and the preventive effect of CFPs on tumor growth required NK and CD8 T cells. Furthermore, CFPs combined with anti-programmed cell death-ligand 1 (PD-L1) antibody (Ab) improved the therapeutic effect of anti-PD-L1 Ab against lung cancer. Therefore, these data demonstrated that the intranasal administration of CFP induced mucosal immunity against lung cancer.

Significance Strongly implicated in effective antitumor immune responses, tumor mutation–derived antigens, or neoantigens, are one of the main targets for cancer vaccines despite uncertainty of the efficacy of this approach. Using a high-throughput screening method, we identify an endogenously immunogenic neoantigen in a commonly used mouse lung tumor model. We also found that the endogenous CD8 T cells specific for this neoantigen expand greatly upon treatment with immune checkpoint inhibitors or vaccination despite the lack of associated tumor regression in this model. In addition to informing neoantigen vaccination strategies and providing an accessible system for testing alternative therapeutics, our results provide insights into the mechanisms for the lack of response observed for a majority of patients treated with checkpoint blockade immunotherapies., Neoantigen-specific T cells are strongly implicated as being critical for effective immune checkpoint blockade treatment (ICB) (e.g., anti–PD-1 and anti–CTLA-4) and are being targeted for vaccination-based therapies. However, ICB treatments show uneven responses between patients, and neoantigen vaccination efficiency has yet to be established. Here, we characterize neoantigen-specific CD8+ T cells in a tumor that is resistant to ICB and neoantigen vaccination. Leveraging the use of mass cytometry combined with multiplex major histocompatibility complex (MHC) class I tetramer staining, we screened and identified tumor neoantigen–specific CD8+ T cells in the Lewis Lung carcinoma (LLC) tumor model (mRiok1). We observed an expansion of mRiok1-specific CD8+ tumor-infiltrating lymphocytes (TILs) after ICB targeting PD-1 or CTLA-4 with no sign of tumor regression. The expanded neoantigen-specific CD8+ TILs remained phenotypically and functionally exhausted but displayed cytotoxic characteristics. When combining both ICB treatments, mRiok1-specific CD8+ TILs showed a stem-like phenotype and a higher capacity to produce cytokines, but tumors did not show signs of regression. Furthermore, combining both ICB treatments with neoantigen vaccination did not induce tumor regression either despite neoantigen-specific CD8+ TIL expansion. Overall, this work provides a model for studying neoantigens in an immunotherapy nonresponder model. We showed that a robust neoantigen-specific T-cell response in the LLC tumor model could fail in tumor response to ICB, which will have important implications in designing future immunotherapeutic strategies.

Background To block repairs of DNA damages, especially the DNA double strand break (DSB) repair, can be used to induce cancer cell death. DSB repair depends on a sequential activation of DNA repair factors that may be potentially targeted for clinical cancer therapy. Up to now, many protein components of DSB repair complex remain unclear or poorly characterized. In this study, we discovered that Transglutaminase 2 (TG2) acted as a new component of DSB repair complex. Methods A bioinformatic analysis was performed to identify DNA damage relative genes from dataset from The Cancer Genome Atlas. Immunofluorescence and confocal microscopy were used to monitor the protein localization and recruitment kinetics. Furthermore, immunoprecipitation and mass spectrometry analysis were performed to determine protein interaction of both full-length and fragments or mutants in distinct domain. In situ lung cancer model was used to study the effects cancer therapy in vivo. Results After DSB induction, cytoplasmic TG2 was extensively mobilized and translocated into nucleus after phosphorylated at T162 site by DNA-PKcs. Nuclear TG2 quickly accumulated at DSB sites and directly interacting with Topoisomerase IIα (TOPOIIα) with its TGase domain to promote DSB repair. TG2 deficient cells lost capacity of DSB repair and become susceptible to ionizing radiation. Specific inhibition of TG2-TOPOIIα interaction by glucosamine also significantly inhibited DSB repair, which increased sensitivity in lung cancer cells and engrafted lung cancers. Conclusions These findings elucidate new mechanism of TG2 in DSB repair trough directly interacting with TOPOIIα, inhibition of which provided potential target for overcoming cancer resistance.

It has been recently reported that CD38 expressed on tumor cells of multiple murine and human origins could be upregulated in response to PD-L1 antibody therapy, which led to dysfunction of tumor-infiltrating CD8+ T immune cells due to increasing the production of adenosine. However, the role of tumor expressed-CD38 on neoplastic formation and progression remains elusive. In the present study, we aimed to delineate the molecular and biochemical function of the tumor-associated CD38 in lung adenocarcinoma progression. Our clinical data showed that the upregulation of tumor-originated CD38 was correlated with poor survival of lung cancer patients. Using multiple in vitro assays we found that the enzymatic activity of tumor expressed-CD38 facilitated lung cancer cell migration, proliferation, colony formation, and tumor development. Consistently, our in vivo results showed that inhibition of the enzymatic activity or antagonizing the enzymatic product of CD38 resulted in the similar inhibition of tumor proliferation and metastasis as CD38 gene knock-out or mutation. At biochemical level, we further identified that cADPR, the mainly hydrolytic product of CD38, was responsible for inducing the opening of TRPM2 iron channel leading to the influx of intracellular Ca2+ and then led to increasing levels of NRF2 while decreasing expression of KEAP1 in lung cancer cells. These findings suggested that malignant lung cancer cells were capable of using cADPR catalyzed by CD38 to facilitate tumor progression, and blocking the enzymatic activity of CD38 could be represented as an important strategy for preventing tumor progression.

Background Chronic alcohol consumption enhances cancer-associated cachexia, which is one of the major causes of decreased survival. The precise molecular mechanism of how alcohol consumption enhances cancer-associated cachexia, especially skeletal muscle loss, remains to be elucidated. Methods We used a mouse model of chronic alcohol consumption, in which 20% (w/v) alcohol was provided as sole drinking fluid, and Lewis lung carcinoma to study the underlying mechanisms. Results We found that alcohol consumption up-regulated the expression of MAFbx, MuRF-1, and LC3 in skeletal muscle, suggesting that alcohol enhanced ubiquitin-mediated proteolysis and LC3-mediated autophagy. Alcohol consumption enhanced phosphorylation of Smad2/3, p38, and ERK and decreased the phosphorylation of FOXO1. These are the signaling molecules governing protein degradation pathways. Moreover, alcohol consumption slightly up-regulated the expression of insulin receptor substrate-1, did not affect phosphatidylinositol-3 kinase, but decreased the phosphorylation of Akt and mammalian target of rapamycin (mTOR), and down-regulated the expression of Raptor and p70 ribosomal kinase S6 kinase, suggesting that alcohol impaired protein synthesis signaling pathway in skeletal muscle of tumor-bearing mice. Alcohol consumption enhanced the expression of myostatin in skeletal muscle, plasma, and tumor, but did not affect the expression of myostatin in non-tumor-bearing mice. In TNFα knockout mice, the effects of alcohol-enhanced expression of myostatin and protein degradation-related signaling molecules, and decreased protein synthesis signaling in skeletal muscle were abolished. Consequently, alcohol consumption neither affected cancer-associated cachexia nor decreased the survival of TNFα KO mice bearing cachectic cancer. Conclusions Chronic alcohol consumption enhances cancer-associated skeletal muscle loss through suppressing Akt/mTOR-mediated protein synthesis pathway and enhancing protein degradation pathways. This process is initiated by TNFα and mediated by myostatin.

Various immune cells are recruited in the tumor microenvironment. It is well established that cellular immune responses, such as cytotoxic or suppressive activities, play an important role in regulating tumor growth and metastasis. However, the contribution of humoral immune responses against tumors is poorly understood. Fc receptors constitute critical elements for the up- or downregulation of immune responses through immune complexes. Here, we examined the potential role of the inhibitory Fc receptor, Fcγ receptor IIB (FcγRIIB), in tumor immunity using a mouse model. Our findings indicated that tumor-specific antibodies are induced in tumor-bearing mice and control tumor immunity. FcγRIIB deletion significantly improved both cellular and humoral immunity against tumors and delayed tumor growth. These findings indicated that spontaneous antibodies against tumors create a suppressive tumor microenvironment through FcγRIIB signaling, thus suggesting an attractive therapeutic target for cancer immunotherapy.

Honokiol, a biphenolic neolignan with inappreciable toxicity isolated from Magnolia officinalis, has been reported to have antiangiogenic and antitumor properties in several tumor cell lines and tumor xenograft models. In our previous study, structural modification by chemical synthesis has been carried out to develop novel honokiol derivatives to improve antitumor activity and clarify the structure-activity relationship. Honokiol analogs, especially 3,5'-diformylated honokiol HK-(CHO)2, have been found to moderately block the newly grown segmental vessels from the dorsal aorta in the transgenic zebrafish-based assay, show antiangiogenic property, and exert medium cytotoxicity against two lung cell lines (Lewis lung carcinoma LL/2 cells and human non-small-cell lung cancer A549 cells). However, the in-vitro and in-vivo antitumor effects of formylated honokiol derivatives against lung carcinoma remained poorly understood. In the study, two formylated honokiol derivatives also showed potent antitumor effects in the Lewis lung carcinoma cells, K-ras-dirived lung adenocarcinoma mice, and a mouse lung tumor xenograft model, with HK-(CHO)2 being most efficacious. The potential mechanism was inhibiting cell proliferation and inducing apoptosis in lung cancer by the regulation of vascular endothelial growth factor A expression. These results further suggested that HK-(CHO)2 might be potential candidates for the treatment of lung carcinoma.

Myeloid-derived suppressor cells (MDSC) can suppress immunity and promote tumorigenesis, and their abundance is associated with poor prognosis. In this study, we show that SUMO1/sentrin-specific peptidase 1 (SENP1) regulates the development and function of MDSC. SENP1 deficiency in myeloid cells promoted MDSC expansion in bone marrow, spleen, and other organs. Senp1−/− MDSC showed stronger immunosuppressive activity than Senp1+/+ MDSC; we observed no defects in the differentiation of myeloid precursor cell in Senp1−/− mice. Mechanistically, SENP1-mediated regulation of MDSC was dependent on STAT3 signaling. We identified CD45 as a specific STAT3 phosphatase in MDSC. CD45 was SUMOylated in MDSC and SENP1 could deconjugate SUMOylated CD45. In Senp1−/− MDSC, CD45 was highly SUMOylated, which reduced its phosphatase activity toward STAT3, leading to STAT3-mediated MDSC development and function. These results reveal a suppressive function of SENP1 in modulating MDSC expansion and function via CD45–STAT3 signaling axis. Significance: These findings show that increased SUMOylation of CD45 via loss of SENP1 suppresses CD45-mediated dephosphorylation of STAT3, which promotes MDSC development and function, leading to tumorigenesis.

To explore AG490 (the inhibitor of Janus kinase (JAK) 2/signal transducer and activator of transcription (STAT) 3 pathway) in cisplatin (DDP)-induced acute kidney injury (AKI) in mice with lung cancer. Mice were randomly divided into normal, model, AG490, DDP and DDP + AG490 groups. The lung cancer models were established except for Normal group. The levels of blood urea nitrogen (BUN) and creatinine and the status of oxidative stress were detected. Then, histological changes were assessed by HE and PAS staining and apoptosis by TUNEL experiment. The molecule expressions were detected by qRT-PCR and western blot, and immunohistochemistry, respectively. DDP inhibited the tumor growth in mice with lung cancer, which was further promoted by the combination with AG490. Mice in the DDP group had elevated levels of BUN and creatinine than those in the Normal group with the increased inflammatory cytokines (TNF-α, IL-6, MCP-1 and CXCL-1) and malondialdehyde (MDA) level and the decreased glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). In addition, DDP could activate the JAK2/STAT3 pathway to promote the apoptosis by upregulating Bax, cleaved caspase-9 and cleaved caspase-3 while downregulating the Bcl-2 in the kidney tissues. DDP + AG490 group showed the alleviated AKI and the improvements in oxidative stress, inflammatory responses and apoptosis in the kidney tissues, as compared to DDP group. AG490 alleviated DDP-induced AKI in lung cancer mice with improved oxidative stress and inflammation, and the suppression of JAK2/STAT3 pathway.

The unbalanced production of pro- and antiangiogenic factors in tumors can lead to aberrant vasculature morphology, angiogenesis, and disease progression. In this study, we report that disease progression in various murine models of solid tumors is associated with increased cleavage of full-length chromogranin A (CgA), a circulating vasoregulatory neurosecretory protein. Cleavage of CgA led to the exposure of the highly conserved PGPQLR site, which corresponds to residues 368–373 of human CgA1-373, a fragment that has proangiogenic activity. Antibodies against this site, unable to bind full-length CgA, inhibited angiogenesis and reduced tumor perfusion and growth. The PGPQLR sequence of the fragment, but not of the precursor, bound the VEGF-binding site of neuropilin-1; the C-terminal arginine (R373) of the sequence was crucial for binding. The proangiogenic activity of the CgA1-373 was blocked by anti-neuropilin-1 antibodies as well as by nicotinic acetylcholine receptor antagonists, suggesting that these receptors, in addition to neuropilin-1, play a role in the proangiogenic activity of CgA1-373. The R373 residue was enzymatically removed in plasma, causing loss of neuropilin-1 binding and gain of antiangiogenic activity. These results suggest that cleavage of the R373R374 site of circulating human CgA in tumors and the subsequent removal of R373 in the blood represent an important “on/off” switch for the spatiotemporal regulation of tumor angiogenesis and may serve as a novel therapeutic target. Significance: This work reveals that the interaction between fragmented chromogranin A and neuropilin-1 is required for tumor growth and represents a novel potential therapeutic target.

Lung cancer is currently the leading cause of cancer-related mortality with very limited effective therapy. Screening of a variety of traditional Chinese medicines (TCMs) for their capacity to inhibit the proliferation of human lung cancer A549 cells and to induce the in vitro maturation of human DCs led to the identification of cryptotanshinone (CT), a compound purified from the TCM Salvia miltiorrhiza Bunge. Here, CT was shown to inhibit the proliferation of mouse Lewis lung carcinoma (LLC) cells by upregulating p53, downregulating cyclin B1 and Cdc2, and, consequently, inducing G2/M cell-cycle arrest of LLC cells. In addition, CT promoted maturation of mouse and human DCs with upregulation of costimulatory and MHC molecules and stimulated DCs to produce TNFα, IL-1β, and IL-12p70, but not IL-10 in vitro. CT-induced maturation of DCs depended on MyD88 and also involved the activation of NF-κB, p38, and JNK. CT was effective in the treatment of LLC tumors and, when used in combination with low doses of anti-PD-L1, cured LLC-bearing mice with the induction of subsequent anti-LLC long-term specific immunity. CT treatment promoted T-cell infiltration and elevated the expression of genes typical of Th1 polarization in LLC tumor tissue. The therapeutic effect of CT and low doses of anti-PD-L1 was reduced by depletion of CD4 and CD8 T cells. This paper provides the first report that CT induces immunological antitumor activities and may provide a new promising antitumor immunotherapeutic. Electronic supplementary material The online version of this article (10.1007/s00262-019-02326-8) contains supplementary material, which is available to authorized users.

The aim of this study was to explore the synergistic anti-tumor effects of cytarabine hyaluronic acid-tyramine (Ara-HA-Tyr) hydrogel conjugates and radiotherapy (RT) in the Lewis lung cancer (LLC) xenograft model, and the mechanisms involved. The radiotherapy sensitization ratio (SER) of 0.5 μg cytarabine (Ara-C) was 1.619 in the LLC cells. Ara-HA-Tyr was prepared by encapsulating Ara-C into hyaluronic acid-tyramine (HA-Tyr) conjugates. The hydrogels were formed through the oxidative coupling of tyramines by hydrogen peroxide (H2O2) and horseradish peroxidase (HRP). Mice engrafted with the LLC cells were given intra-tumoral injections of saline, Ara-C or Ara-HA-Tyr, with or without RT. The combination of Ara-HA-Tyr and RT increased survival compared to free Ara-C and RT (p

Oestrogen signalling pathways are emerging targets for lung cancer therapy. Unravelling the contribution of oestrogens in lung cancer development is a pre-requisite to support the development of sex-based treatments and identify patients who could potentially benefit from anti-oestrogen treatments. In this study, we highlight the contribution of lymphatic and blood endothelia in the sex-dependent modulation of lung cancer. The orthotopic graft of syngeneic lung cancer cells into immunocompetent mice showed that lung tumours grow faster in female mice than in males. Moreover, oestradiol (E2) promoted tumour development, increased lymph/angiogenesis and VEGFA and bFGF levels in lung tumours of females through an oestrogen receptor (ER) alpha-dependent pathway. Furthermore, while treatment with ERb antagonist was inefficient, ERa antagonist (MPP) and tamoxifen decreased lung tumour volumes, altered blood and lymphatic vasculature and reduced VEGFA and bFGF levels in females, but not in males. Finally, the quantification of lymphatic and blood vasculature of lung adenocarcinoma biopsies from patients aged between 35 and 55 years revealed more extensive lymphangiogenesis and angiogenesis in tumour samples issued from women than from men. In conclusion, our findings highlight an E2/ERa-dependent modulation of lymphatic and blood vascular components of lung tumour microenvironment. Our study has potential clinical implication in a personalised medicine perspective by pointing to the importance of oestrogen status or supplementation on lung cancer development that should be considered to adapt therapeutic strategies., info:eu-repo/semantics/published

Non-small cell lung cancer (NSCLC) has become one of the most general malignancies in the world and has been shown to be the leading cause of cancer-related deaths. Traditional Chinese medicine (TCM) is considered to be a useful medicine for survival, and has been used in Asia for thousands of years. Hedyotis diffusa Willd (HDW) is an important folk herb that is used in clinical treatment of various cancers in various Chinese medicine prescriptions. However, its underlying mechanism of action remains unclear. Presently, we used an innovative system-pharmacology platform to systematically uncover the pharmacological mechanisms of HDW in the treatment of NSCLC from molecules, targets, and pathway levels. The results show that HDW treatment of NSCLC may activate immunity, achieve anti-inflammatory, anti-proliferative and anti-migration therapeutic effects by regulating multiple pathways. This research provides a new idea for understanding the mechanism of TCM and promotes to develop potential drugs from HDW in modern medicine.

We compared the therapeutic efficacy of two recently developed experimental anticancer technologies: 1) in situ vaccination based on local immunotherapy with CpG oligonucleotides and anti-OX40 antibodies to activate antitumor immune response and 2) "Karanahan" technology [from the Sanskrit kāraṇa ('source') + han ('to kill')] based on the combined injection of cyclophosphamide and double-stranded DNA to eradicate cancer stem cells.The anticancer approaches were compared on three types of mouse malignant tumors with different grades of immunogenicity: weakly immunogenic carcinoma Krebs-2, moderately immunogenic Lewis carcinoma, and highly immunogenic A20 В-cellular lymphoma.Our results indicated that in situ vaccination was the most effective against the highly immunogenic tumor А20. In addition, "Karanahan" demonstrated high efficiency in all types of tumors, regardless of their immunogenicity or size."Karanahan" therapy showed higher efficacy relative to in situ vaccination with CpG oligonucleotides and anti-OX40 antibodies.

Advanced Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with a poor prognosis. The anti-malaria compounds dihydroartemisinin (DHA) have shown to regulate multiple targets and signaling pathways in cancers, but a global view of its mechanism of action remains elusive. In present study, we integrated network pharmacology and in vitro and in vivo experimental models to investigate the mechanisms of DHA in preventing NSCLC proliferation. We first proved that DHA inhibits the growth of lung cancer via inducing cell apoptosis and cell cycle arrest, then we integrated information from publicly available databases to predict interactions between DHA and its potential targets in NSCLC, as well as the signaling pathways involved. In this way we identified 118 common targets of DHA and NSCLC, and further analyzed with the correlation between these targets by KEGG and GO analysis. Our data indicate that mTOR/HIF-1α signaling is one of potential critical pathways involved in DHA-induced tumor inhibition in NSCLC. Finally, the data from human and mouse lung cancer cell lines and in mouse Lewis lung cancer models showed that DHA does decrease the expression level of mTOR and HIF-1α which supported the potential roles of mTOR/HIF-1α Signaling in NSCLC and deserves further investigation.

Highlight We report that gastric cancer patients exhibiting high levels of heparanase 2 (Hpa2) survive longer. Similarly, mice administrated with gastric carcinoma cells engineered to overexpress Hpa2 produced smaller tumors and survived longer than mice administrated with control cells. These beneficial effects were found to associate with increased phosphorylation of AMP-activated protein kinase (AMPK) that play an instrumental role in cell metabolism and is situated at the center of a tumor suppressor network. We also found that MG132, an inhibitor of the proteasome that results in proteotoxic stress, prominently enhances Hpa2 expression. Notably, Hpa2 induction by MG132 appeared to be mediated by AMPK, thus establishing a loop that feeds itself where Hpa2 enhances AMPK phosphorylation that, in turn, induces Hpa2 expression, possibly leading to attenuation of gastric tumorigenesis., Heparanase is highly implicated in tumor metastasis due to its capacity to cleave heparan sulfate and, consequently, remodel the extracellular matrix underlying epithelial and endothelial cells. In striking contrast, only little attention was given to its close homolog, heparanase 2 (Hpa2), possibly because it lacks heparan sulfate-degrading activity typical of heparanase. We subjected sections of gastric carcinoma to immunostaining and correlated Hpa2 immunoreactivity with clinical records, including tumor grade, stage and patients' status. We over-expressed Hpa2 in gastric carcinoma cell lines and examined their tumorigenic properties in vitro and in vivo. We also evaluated the expression of Hpa2 by gastric carcinoma cells following inhibition of the proteasome, leading to proteotoxic stress, and the resulting signaling responsible for Hpa2 gene regulation. Here, we report that gastric cancer patients exhibiting high levels of Hpa2 survive longer. Similarly, mice administrated with gastric carcinoma cells engineered to over-express Hpa2 produced smaller tumors and survived longer than mice administrated with control cells. This was associated with increased phosphorylation of AMP-activated protein kinase (AMPK), a kinase that is situated at the center of a tumor suppressor network. We also found that MG132, an inhibitor of the proteasome that results in proteotoxic stress, prominently enhances Hpa2 expression. Notably, Hpa2 induction by MG132 appeared to be mediated by AMPK, and AMPK was found to induce the expression of Hpa2, thus establishing a loop that feeds itself where Hpa2 enhances AMPK phosphorylation that, in turn, induces Hpa2 expression, leading to attenuation of gastric tumorigenesis. These results indicate that high levels of Hpa2 in some tumors are due to stress conditions that tumors often experience due to their high rates of cell proliferation and high metabolic demands. This increase in Hpa2 levels by the stressed tumors appears critically important for patient outcomes.

Aging is a complex physiological process that leads to the progressive decline of metabolic and immune function, among other biological mechanisms. As global life expectancy increases, it is important to understand determinants of healthy aging—including environmental and genetic factors—and thus slow the onset or progression of age-related disease. Environmental enrichment (EE) is a housing environment wherein laboratory animals engage with complex physical and social stimulation. EE is a prime model to understand environmental influences on aging dynamics, as it confers an antiobesity and anticancer phenotype that has been implicated in healthy aging and health span extension. Although EE is frequently used to study malignancies in young mice, fewer studies characterize EE-cancer outcomes in older mice. Here, we used young (3-month-old) and aged (14-month-old) female C57BL/6 mice to determine whether EE would be able to mitigate age-related deficiencies in metabolic function and thus alter Lewis lung carcinoma (LLC) growth. Overall, EE improved metabolic function, resulting in reduced fat mass, increased lean mass, and improved glycemic processing; many of these effects were stronger in the aged cohort than in the young cohort, indicating an age-driven effect on metabolic responses. In the aged-EE cohort, subcutaneously implanted LLC tumor growth was inhibited and tumors exhibited alterations in various markers of apoptosis, proliferation, angiogenesis, inflammation, and malignancy. These results validate EE as an anticancer model in aged mice and underscore the importance of understanding environmental influences on cancer malignancy in aged populations. Prevention Relevance: Environmental enrichment (EE) serves as a model of complex physical and social stimulation. This study validates EE as an anticancer intervention paradigm in aged mice and underscores the importance of understanding environmental influences on cancer malignancy in aged populations.

Veglia et al. characterize the heterogeneity of polymorphonuclear neutrophils (PMNs) in the tumor microenvironment, spleen, and peripheral blood. The identification of neutrophil populations with potent immune suppressive activity opens selective targeting opportunities., In this study, using single-cell RNA-seq, cell mass spectrometry, flow cytometry, and functional analysis, we characterized the heterogeneity of polymorphonuclear neutrophils (PMNs) in cancer. We describe three populations of PMNs in tumor-bearing mice: classical PMNs, polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), and activated PMN-MDSCs with potent immune suppressive activity. In spleens of mice, PMN-MDSCs gradually replaced PMNs during tumor progression. Activated PMN-MDSCs were found only in tumors, where they were present at the very early stages of the disease. These populations of PMNs in mice could be separated based on the expression of CD14. In peripheral blood of cancer patients, we identified two distinct populations of PMNs with characteristics of classical PMNs and PMN-MDSCs. The gene signature of tumor PMN-MDSCs was similar to that in mouse activated PMN-MDSCs and was closely associated with negative clinical outcome in cancer patients. Thus, we provide evidence that PMN-MDSCs are a distinct population of PMNs with unique features and potential for selective targeting opportunities.

BackgroundModulation and depletion strategies of regulatory T cells (Tregs) constitute valid approaches in antitumor immunotherapy but suffer from severe adverse effects due to their lack of selectivity for the tumor-infiltrating (ti-)Treg population, indicating the need for a ti-Treg specific biomarker.MethodsWe employed single-cell RNA-sequencing in a mouse model of non-small cell lung carcinoma (NSCLC) to obtain a comprehensive overview of the tumor-infiltrating T-cell compartment, with a focus on ti-Treg subpopulations. These findings were validated by flow cytometric analysis of both mouse (LLC-OVA, MC38 and B16-OVA) and human (NSCLC and melanoma) tumor samples. We generated two CCR8-specific nanobodies (Nbs) that recognize distinct epitopes on the CCR8 extracellular domain. These Nbs were formulated as tetravalent Nb-Fc fusion proteins for optimal CCR8 binding and blocking, containing either an antibody-dependent cell-mediated cytotoxicity (ADCC)-deficient or an ADCC-prone Fc region. The therapeutic use of these Nb-Fc fusion proteins was evaluated, either as monotherapy or as combination therapy with anti-programmed cell death protein-1 (anti-PD-1), in both the LLC-OVA and MC38 mouse models.ResultsWe were able to discern two ti-Treg populations, one of which is characterized by the unique expression of Ccr8 in conjunction with Treg activation markers. Ccr8 is also expressed by dysfunctional CD4+ and CD8+ T cells, but the CCR8 protein was only prominent on the highly activated and strongly T-cell suppressive ti-Treg subpopulation of mouse and human tumors, with no major CCR8-positivity found on peripheral Tregs. CCR8 expression resulted from TCR-mediated Treg triggering in an NF-κB-dependent fashion, but was not essential for the recruitment, activation nor suppressive capacity of these cells. While treatment of tumor-bearing mice with a blocking ADCC-deficient Nb-Fc did not influence tumor growth, ADCC-prone Nb-Fc elicited antitumor immunity and reduced tumor growth in synergy with anti-PD-1 therapy. Importantly, ADCC-prone Nb-Fc specifically depleted ti-Tregs in a natural killer (NK) cell-dependent fashion without affecting peripheral Tregs.ConclusionsCollectively, our findings highlight the efficacy and safety of targeting CCR8 for the depletion of tumor-promoting ti-Tregs in combination with anti-PD-1 therapy.

Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a repair enzyme for 3'-end DNA lesions, predominantly stalled DNA-topoisomerase 1 (Top1) cleavage complexes. Tdp1 is a promising target for anticancer therapy based on DNA damage caused by Top1 poisoning. Earlier, we have reported about usnic acid enamine derivatives that are Tdp1 inhibitors sensitizing tumor cells to the action of Top1 poison (Zakharenko in J Nat Prod 79:2961-2967, 2016). In the present work, we showed a sensitizing effect of an enamine derivative of usnic acid (when administered intragastrically) on Lewis lung carcinoma in mice in combination with topotecan (TPT, Top1 poison used in the clinic). In the presence of the usnic acid derivative, both the volume of the primary tumor and the number of metastases significantly diminished. The absence of acute toxicity of this compound was demonstrated, as was the importance of the method of its administration for the manifestation of the sensitizing properties.

Poly-(ADP-Ribose)-Polymerase inhibitors (PARPi) were reported as radiosensitizers in non-small cell lung cancer (NSCLC) with wide-type epidermal growth factor receptor (EGFR), but the effects of radiation combined with PARPi were not investigated in EGFR-mutated NSCLC. Moreover, the underlying mechanisms were not well examined. This study aimed to study the efficacy of radiation combined with niraparib in EGFR-mutated NSCLC and explore their influence on the immune system.Clone formation and apoptosis assay were conducted to explore the effects of niraparib and radiation. Immunofluorescence was conducted to detect the double-strand DNA breaks. Real-time PCR and immunoblotting were employed to evaluate the activation of STING/TBK1/TRF3 pathway and the expression levels of interferon β, CCL5 and CXCL10. Immunocompetent mice model bearing with subcutaneous Lewis lung cancer was established to confirm the results in vivo.Niraparib and radiation were synergistic to inhibit tumor both in vitro and in vivo. Radiation plus niraparib could activate anti-tumor immunity, which appeared as increased CD8PARPi not only as a radiosensitizer inhibited EGFR-mutated NSCLC tumor growth, but also cooperated with radiation to promote anti-tumor immune responses.

Purpose Harnessing the immune-stimulatory effects of radiation by combining it with immunotherapy is a promising new treatment strategy. However, more studies characterizing immunotherapy and radiation dose scheduling for the optimal therapeutic effect is essential for designing clinical trials. Methods and Materials A new ablative radiation dosing scheme, personalized ultrafractionated stereotactic adaptive radiation therapy (PULSAR), was tested in combination with α-PD-L1 therapy in immune-activated and resistant syngeneic immunocompetent mouse models of cancer. Specifically, tumor growth curves comparing immunotherapy and radiation therapy dose sequencing were evaluated in immunologically cold and hot tumor models. The response relative to cytotoxic killer T cells was evaluated using an α-CD8 depleting antibody, and immunologic memory was tested by tumor rechallenge of cured mice. Results We report that both radiation and immunotherapy sequencing, as well as radiation therapy fraction spacing, affect the combination treatment response. Better tumor control was achieved by giving α-PD-L1 therapy during or after radiation, and spacing fractions 10 days apart (PULSAR) achieved better tumor control than traditional daily fractions. We showed that CD8+ depleting antibody abrogated tumor control in the PULSAR combination treatment, and certain treatment schedules induced immunologic memory. Conclusions These results illustrate that radiation therapy dosing and scheduling affect tumor control, in combination with checkpoint blockade therapies. PULSAR-style radiation dosing is more complementary in combination with single-agent immunotherapy than traditional daily fractions in this preclinical model. Preclinical investigation could prove helpful in designing clinical trials investigating combination therapy.

Lung cancer is the leading cause of cancer-related deaths. While the recent use of immune checkpoint inhibitors significantly improves patient outcomes, responsiveness remains restricted to a small proportion of patients. Conventional dendritic cells (DCs) play a major role in anticancer immunity. In mice, two subpopulations of DCs are found in the lung: DC2s (CD11b+Sirpα+) and DC1s (CD103+XCR1+), the latest specializing in the promotion of anticancer immune responses. However, the impact of lung cancer on DC populations and the consequent influence on the anticancer immune response remain poorly understood. To address this, DC populations were studied in murine models of Lewis Lung Carcinoma (LLC) and melanoma-induced lung metastasis (B16F10). We report that direct exposure to live or dead cancer cells impacts the capacity of DCs to differentiate into CD103+ DC1s, leading to profound alterations in CD103+ DC1 proportions in the lung. In addition, we observed the accumulation of CD103loCD11b+ DCs, which express DC2 markers IRF4 and Sirpα, high levels of T-cell inhibitory molecules PD-L1/2 and the regulatory molecule CD200. Finally, DC1s were injected in combination with an immune checkpoint inhibitor (anti-PD-1) in the B16F10 model of resistance to the anti-PD-1 immune checkpoint therapy; the co-injection restored sensitivity to immunotherapy. Thus, we demonstrate that lung tumor development leads to the accumulation of CD103loCD11b+ DCs with a regulatory potential combined with a reduced proportion of highly-specialized antitumor CD103+ DC1s, which could promote cancer growth. Additionally, promoting an anticancer DC signature could be an interesting therapeutic avenue to increase the efficacy of existing immune checkpoint inhibitors.

BACKGROUND Inhibition of aerobic glycolysis of cancer cells is considered a promising therapeutic strategy for the treatment of neoplasms. Some inhibitors of energy metabolism can affect not only tumor cells but also the functional polarization of tumor-associated macrophages, which may either enhance the antitumor effect of such agents or impair their antitumor efficacy. AIM To investigate the effect of oxamate, a lactate dehydrogenase (LDH) inhibitor, on the polarization of peritoneal macrophages (PMP) in both intact mice and mice with transplanted Lewis lung carcinoma (LLC). MATERIALS AND METHODS The low-metastatic LLC variant, LLC/R9, was transplanted to female C57Bl/6 mice. Sodium oxamate was used as the test agent at concentrations of 0.02, 0.2, and 2 mg/ml. Macrophage polarization in tumor-bearing mice was estimated on day 23 after tumor transplantation by assessing nitric oxide (NO) production and arginase activity as functional indices of PMPs polarization. RESULTS Oxamate can affect the functional polarization of PMPs in both intact mice and animals with transplanted LLC/R9. Oxamate in all studied concentrations changed the markers of PMPs polarization in intact mice (decreasing NO levels and activating arginase activity) that indicated the stimulation of M2 polarization. In tumor-bearing animals, stimulation of M2 polarization is observed at low concentrations of oxamate (0.02 mg/ml), but its high concentrations (2.0 mg/ml) causes M1 polarization, which is characterized by three-fold increase in the level of NO and a decrease in the level of arginase activity. CONCLUSION Oxamate, an inhibitor of LDH, can stimulate M2 polarization of peritoneal macrophages of mice bearing LLC in a dose-dependent manner.

Tumor-associated macrophages (TAMs) can dampen the antitumor activity of T cells, yet the underlying mechanism remains incompletely understood. Here, we show that C1q

A major mechanism through which neutrophils have been suggested to modulate tumor progression involves the interaction and subsequent modulation of other infiltrating immune cells. B cells have been found to infiltrate various cancer types and play a role in tumor immunity, offering new immunotherapy opportunities. Nevertheless, the specific impact of tumor-associated neutrophils (TAN) on B cells has largely been overlooked. In the current study, we aimed to characterize the role of TANs in the recruitment and modulation of B cells in the tumor microenvironment (TME). We showed that TANs actively participate in the recruitment of B cells to the TME and identified TNFα as the major cytokine mediating B-cell chemotaxis by TANs. The recruitment of CD45+B220+CD138− splenic B cells by TANs in vitro resulted in B-cell phenotypic modulation, with 68.6% ± 2.1% of the total migrated B cells displaying a CD45−B220+CD138+ phenotype, which is typical for plasma cells. This phenotype mirrored the large proportion (54.0% ± 6.1%) of CD45−B220+CD138+ intratumoral B cells (i.e., plasma cells) in Lewis lung carcinoma tumors. We next confirmed that the differentiation of CD45+B220+CD138− B cells to functionally active CD45−B220+CD138+ plasma cells required contact with TANs, was independent of T cells, and resulted in IgG production. We further identified membranal B-cell activating factor (BAFF) on TANs as a potential contact mechanism mediating B-cell differentiation, as blocking BAFF-receptor (BAFF-R) significantly reduced IgG production by 20%. Our study, therefore, demonstrates that TANs drive the recruitment and modulation of B cells into plasma cells in the TME, hence opening new avenues in the targeting of the immune system in cancer.

Engineering T cells to express chimeric antigen receptors (CARs) specific for antigens on hematological cancers has yielded remarkable clinical responses, but with solid tumors, benefit has been more limited. This may reflect lack of suitable target antigens, immune evasion mechanisms in malignant cells, and/or lack of T cell infiltration into tumors. An alternative approach, to circumvent these problems, is targeting the tumor vasculature rather than the malignant cells directly. CLEC14A is a glycoprotein selectively overexpressed on the vasculature of many solid human cancers and is, therefore, of considerable interest as a target antigen. Here, we generated CARs from 2 CLEC14A-specific antibodies and expressed them in T cells. In vitro studies demonstrated that, when exposed to their target antigen, these engineered T cells proliferate, release IFN-γ, and mediate cytotoxicity. Infusing CAR engineered T cells into healthy mice showed no signs of toxicity, yet these T cells targeted tumor tissue and significantly inhibited tumor growth in 3 mouse models of cancer (Rip-Tag2, mPDAC, and Lewis lung carcinoma). Reduced tumor burden also correlated with significant loss of CLEC14A expression and reduced vascular density within malignant tissues. These data suggest the tumor vasculature can be safely and effectively targeted with CLEC14A-specific CAR T cells, offering a potent and widely applicable therapy for cancer., T cells expressing a chimeric antigen receptor specific for the tumor vascular marker CLEC14A inhibited tumor growth in three mouse cancer models.