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Scientific Reports Jan 2021Glioblastoma (GBM) is the most aggressive brain primary malignancy. Toll-like receptor 4 (TLR4) has a dual role in cell fate, promoting cell survival or death depending...
Glioblastoma (GBM) is the most aggressive brain primary malignancy. Toll-like receptor 4 (TLR4) has a dual role in cell fate, promoting cell survival or death depending on the context. Here, we analyzed TLR4 expression in different grades of astrocytoma, and observed increased expression in tumors, mainly in GBM, compared to non-neoplastic brain tissue. TLR4 role was investigated in U87MG, a GBM mesenchymal subtype cell line, upon LPS stimulation. p65 nuclear translocation was observed in late phase, suggesting TLR4-non-canonical pathway activation. In fact, components of ripoptosome and inflammasome cascades were upregulated and they were significantly correlated in GBMs of the TCGA-RNASeq dataset. Moreover, an increased apoptotic rate was observed when the GBM-derived U87MG cells were co-treated with LPS and Temozolomide (TMZ) in comparison to TMZ alone. Increased TLR4 immunostaining was detected in nuclei of U87MG cells 12 h after LPS treatment, concomitant to activation of DNA repair genes. Time-dependent increased RAD51, FEN1 and UNG expression levels were confirmed after LPS stimulation, which may contribute to tumor cell fitness. Moreover, the combined treatment with the RAD51 inhibitor, Amuvatinib in combination with, TMZ after LPS stimulation reduced tumor cell viability more than with each treatment alone. In conclusion, our results suggest that stimulation of TLR4 combined with pharmacological inhibition of the DNA repair pathway may be an alternative treatment for GBM patients.
Topics: Active Transport, Cell Nucleus; Brain Neoplasms; Cell Line, Tumor; Cell Nucleus; DNA Repair; DNA, Neoplasm; Female; Glioblastoma; Humans; Male; Neoplasm Proteins; Signal Transduction; Toll-Like Receptor 4; Transcription Factor RelA
PubMed: 33446690
DOI: 10.1038/s41598-020-79356-1 -
Cancers Jan 2022Tumors deploy various immune-evasion mechanisms that create a suppressive environment and render effector T-cells exhausted and inactive. Therefore, a rational...
Tumors deploy various immune-evasion mechanisms that create a suppressive environment and render effector T-cells exhausted and inactive. Therefore, a rational utilization of checkpoint inhibitors may alleviate exhaustion and may partially restore antitumor functions. However, in high-tumor-burden models, the checkpoint blockade fails to maintain optimal efficacy, and other interventions are necessary to overcome the inhibitory tumor stroma. One such strategy is the use of radiotherapy to reset the tumor microenvironment and maximize systemic antitumor outcomes. In this study, we propose the use of anti-PD1 and anti-TIGIT checkpoint inhibitors in conjunction with our novel RadScopal technique to battle highly metastatic lung adenocarcinoma tumors, bilaterally established in 129Sv/Ev mice, to mimic high-tumor-burden settings. The RadScopal approach is comprised of high-dose radiation directed at primary tumors with low-dose radiation delivered to secondary tumors to improve the outcomes of systemic immunotherapy. Indeed, the triple therapy with RadScopal + anti-TIGIT + anti-PD1 was able to prolong the survival of treated mice and halted the growth of both primary and secondary tumors. Lung metastasis counts were also significantly reduced. In addition, the low-dose radiation component reduced TIGIT receptor (PVR) expression by tumor-associated macrophages and dendritic cells in secondary tumors. Finally, low-dose radiation within triple therapy decreased the percentages of TIGIT exhausted T-cells and TIGIT regulatory T-cells. Together, our translational approach provides a new treatment alternative for cases refractory to other checkpoints and may bring immunotherapy into a new realm of systemic disease control.
PubMed: 35008385
DOI: 10.3390/cancers14010221 -
Journal of Nanobiotechnology Sep 2022While improvements in immunoradiotherapy have significantly improved outcomes for cancer patients, this treatment approach has nevertheless proven ineffective at...
BACKGROUND
While improvements in immunoradiotherapy have significantly improved outcomes for cancer patients, this treatment approach has nevertheless proven ineffective at controlling the majority of malignancies. One of the mechanisms of resistance to immunoradiotherapy is that immune cells may be suppressed via the myriad of different immune checkpoint receptors. Therefore, simultaneous blockade of multiple immune checkpoint receptors may enhance the treatment efficacy of immunoradiotherapy.
METHODS
We combined NBTXR3-enhanced localized radiation with the simultaneous blockade of three different checkpoint receptors: PD1, LAG3, and TIGIT, and tested the treatment efficacy in an anti-PD1-resistant lung cancer model in mice. 129 Sv/Ev mice were inoculated with fifty thousand αPD1-resistant 344SQR cells in the right leg on day 0 to establish primary tumors and with the same number of cells in the left leg on day 4 to establish the secondary tumors. NBTXR3 was intratumorally injected into the primary tumors on day 7, which were irradiated with 12 Gy on days 8, 9, and 10. Anti-PD1 (200 µg), αLAG3 (200 µg), and αTIGIT (200 µg) were given to mice by intraperitoneal injections on days 5, 8, 11, 14, 21, 28, 35, and 42.
RESULTS
This nanoparticle-mediated combination therapy is effective at controlling the growth of irradiated and distant unirradiated tumors, enhancing animal survival, and is the only one that led to the destruction of both tumors in approximately 30% of the treated mice. Corresponding with this improved response is robust activation of the immune response, as manifested by increased numbers of immune cells along with a transcriptional signature of both innate and adaptive immunity within the tumor. Furthermore, mice treated with this combinatorial therapy display immunological memory response when rechallenged by the same cancer cells, preventing tumor engraftment.
CONCLUSION
Our results strongly attest to the efficacy and validity of combining nanoparticle-enhanced radiotherapy and simultaneous blockade of multiple immune checkpoint receptors and provide a pre-clinical rationale for investigating its translation into human patients.
Topics: Animals; Antigens, CD; Antineoplastic Agents; Humans; Lung Neoplasms; Mice; Nanoparticles; Radioimmunotherapy; Receptors, Immunologic; Treatment Outcome; Lymphocyte Activation Gene 3 Protein
PubMed: 36123677
DOI: 10.1186/s12951-022-01621-4 -
Journal of Nanobiotechnology Dec 2021Combining radiotherapy with PD1 blockade has had impressive antitumor effects in preclinical models of metastatic lung cancer, although anti-PD1 resistance remains...
A radioenhancing nanoparticle mediated immunoradiation improves survival and generates long-term antitumor immune memory in an anti-PD1-resistant murine lung cancer model.
BACKGROUND
Combining radiotherapy with PD1 blockade has had impressive antitumor effects in preclinical models of metastatic lung cancer, although anti-PD1 resistance remains problematic. Here, we report results from a triple-combination therapy in which NBTXR3, a clinically approved nanoparticle radioenhancer, is combined with high-dose radiation (HDXRT) to a primary tumor plus low-dose radiation (LDXRT) to a secondary tumor along with checkpoint blockade in a mouse model of anti-PD1-resistant metastatic lung cancer.
METHODS
Mice were inoculated with 344SQR cells in the right legs on day 0 (primary tumor) and the left legs on day 3 (secondary tumor). Immune checkpoint inhibitors (ICIs), including anti-PD1 (200 μg) and anti-CTLA4 (100 μg) were given intraperitoneally. Primary tumors were injected with NBTXR3 on day 6 and irradiated with 12-Gy (HDXRT) on days 7, 8, and 9; secondary tumors were irradiated with 1-Gy (LDXRT) on days 12 and 13. The survivor mice at day 178 were rechallenged with 344SQR cells and tumor growth monitored thereafter.
RESULTS
NBTXR3 + HDXRT + LDXRT + ICIs had significant antitumor effects against both primary and secondary tumors, improving the survival rate from 0 to 50%. Immune profiling of the secondary tumors revealed that NBTXR3 + HDXRT + LDXRT increased CD8 T-cell infiltration and decreased the number of regulatory T (Treg) cells. Finally, none of the re-challenged mice developed tumors, and they had higher percentages of CD4 memory T cells and CD4 and CD8 T cells in both blood and spleen relative to untreated mice.
CONCLUSIONS
NBTXR3 nanoparticle in combination with radioimmunotherapy significantly improves anti-PD1 resistant lung tumor control via promoting antitumor immune response.
Topics: Animals; Drug Resistance, Neoplasm; Female; Immune Checkpoint Inhibitors; Immunologic Memory; Lung Neoplasms; Mice; Nanoparticles; Neoplasms, Experimental; Radiation-Sensitizing Agents; Radioimmunotherapy
PubMed: 34895262
DOI: 10.1186/s12951-021-01163-1 -
Biomedicine & Pharmacotherapy =... Oct 2019Multidrug resistance protein 1 (MRP1/ABCC1) actively transports a variety of drugs, toxic molecules and important physiological substrates across the plasma membrane. It...
Multidrug resistance protein 1 (MRP1/ABCC1) actively transports a variety of drugs, toxic molecules and important physiological substrates across the plasma membrane. It can confer broad-spectrum multidrug resistance and can decrease the bioavailability of many important drugs. Substrates of MRP1 include anti-cancer agents, antibiotics, antivirals, antidepressants and anti-inflammatory drugs. Using calcein as a fluorescent reporter in a high content uptake assay, we recently reported the identification of 12 MRP1 inhibitors after screening an anti-cancer library of 386 compounds. Here, we describe the development of a new high content imaging-based uptake assay using doxorubicin as a fluorescent reporter. Screening the same anti-cancer library of 386 compounds, the new assay identified a total of 28 MRP1 inhibitors including 16 inhibitors that have not been previously reported as inhibitors of MRP1. Inhibition of MRP1 activity was confirmed using flow cytometry and confocal microscopy-based transport assays. Six drugs (afatinib, celecoxib, doramapimod, mifepristone, MK-2206 and rosiglitazone) were evaluated for their ability to reverse resistance of MRP1-overexpressing H69AR lung cancer cells against vincristine, doxorubicin and etoposide. Mifepristone and doramapimod were most effective in reversal of resistance against vincristine while mifepristone and rosiglitazone were most successful in resensitizing H69AR cells against doxorubicin. Furthermore, resistance towards etoposide was completely reversed in the presence of celecoxib or doramapimod. Selected drugs were also evaluated for resistance reversal in HEK cells that overexpress P-glycoprotein or breast cancer resistance protein. Our results indicate mifepristone and doramapimod as pan inhibitors of these three drug transporters while celecoxib exhibited selective MRP1 inhibition. Together, our findings signify the importance of MRP1 in drug discovery and demonstrate the effectiveness and value of doxorubicin-based high content screening approach. Anti-cancer agents that exhibit MRP1 inhibition may be used to reverse multidrug resistance or to improve the efficacy and reduce the toxicity of various cancer chemotherapies. On the other hand, anti-cancer drugs that did not interact with MRP1 carry a low risk for developing MRP1-mediated resistance.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Antineoplastic Agents; Biological Assay; Cell Line, Tumor; Doxorubicin; Drug Resistance, Neoplasm; Fluoresceins; Fluorescent Dyes; HEK293 Cells; High-Throughput Screening Assays; Humans; Multidrug Resistance-Associated Proteins; Protein Transport; Reproducibility of Results
PubMed: 31401398
DOI: 10.1016/j.biopha.2019.109289 -
Journal For Immunotherapy of Cancer Sep 2019Preclinical evidence suggests that low-dose radiation may overcome the inhibitory effects of the tumor stroma and improve a tumor's response to immunotherapy, when...
BACKGROUND
Preclinical evidence suggests that low-dose radiation may overcome the inhibitory effects of the tumor stroma and improve a tumor's response to immunotherapy, when combined with high-dose radiation to another tumor. The aim of this study was to evaluate tumor responses to this combination in a clinical setting.
METHODS
A post-hoc analysis of 3 ongoing immunoradiation trials was performed. Twenty-six (of 155) patients received low-dose radiation (1-20 Gy total), either as scatter from high-dose radiation or from intentional treatment of a second isocenter with low-dose radiation, were evaluated for response. The low-dose lesions were compared to lesions that received no radiation (< 1 Gy total). Response rates, both defined as complete and partial responses as defined by RECIST criteria were used to compare lesion types.
RESULTS
The 26 patients had a total of 83 lesions for comparison (38 receiving low-dose, 45 receiving no-dose). The average dose given to low-dose lesions was 7.3 Gy (1.1-19.4 Gy), and the average time to response was 56 days. Twenty-two out of 38 (58%) low-dose lesions met the PR/CR criteria for RECIST compared with 8 out of 45 (18%) no-dose lesions (P = 0.0001). The median change for longest diameter size for low-dose lesions was - 38.5% compared to 8% in no-dose lesions (P < 0.0001). Among the low-dose lesions that had at least one no-dose lesion within the same patient as a control (33 and 45 lesions respectively), 12 low-dose lesions (36%) responded without a corresponding response in their no-dose lesions; Conversely, two (4%) of the no-dose lesions responded without a corresponding response in their low-dose lesion (P = 0.0004).
CONCLUSIONS
Low-dose radiation may increase systemic response rates of metastatic disease treated with high-dose radiation and immunotherapy.
Topics: Adult; Aged; Aged, 80 and over; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Combined Modality Therapy; Dose-Response Relationship, Radiation; Female; Follow-Up Studies; Humans; Immunotherapy; Male; Middle Aged; Neoplasms; Prognosis; Prospective Studies; Radiosurgery; Randomized Controlled Trials as Topic; Retrospective Studies; Survival Rate; Young Adult
PubMed: 31484556
DOI: 10.1186/s40425-019-0718-6 -
Cancer Apr 2019
Topics: Anthracyclines; Antibodies, Monoclonal, Humanized; Antineoplastic Agents, Immunological; Antineoplastic Combined Chemotherapy Protocols; Benzodiazepinones; Carboplatin; Clinical Decision-Making; Disease Progression; Etoposide; Humans; Immunoconjugates; Irinotecan; Liver Neoplasms; Lung Neoplasms; Molecular Targeted Therapy; Neoplasm Recurrence, Local; Nivolumab; Paclitaxel; Piperazines; Pyrimidines; Salvage Therapy; Small Cell Lung Carcinoma; Temozolomide; Thiourea; Topotecan
PubMed: 30561759
DOI: 10.1002/cncr.31849