Comparison of Tumor Non-specific and PD-L1 Specific Imaging by Near-Infrared Fluorescence/Cerenkov Luminescence Dual-Modality In-situ Imaging.

Background: Labeled antibodies are excellent imaging agents in oncology to non-invasively visualize cancer-related antigens expression levels. However, tumor tracer uptake (TTU) of specific antibodies in-vivo may be inferior to non-specific IgG in some cases. Objectives: To explore factors affecting labeled antibody visualization by PD-L1 specific and non-specific imaging of nude mouse tumors. Methods: TTU was observed in RKO model on Cerenkov luminescence (CL) and near-infrared fluorescence (NIRF) imaging of radionuclide 131I or NIRF dyes labeled Atezolizumab and IgG. A mixture of NIRF dyes labeled Atezolizumab and 131I-labeled IgG was injected, and TTU was observed in the RKO and HCT8 model by NIRF/CL dual-modality in-situ imaging. TTU were observed by 131I-labeled Atezolizumab and IgG in-vitro distribution. Results: Labeled IgG concentrated more in tumors than Atezolizumab. NIRF/CL imaging in 24 to 168 h showed that TTU gradually decreased over time, which decreased more slowly on CL imaging compared to NIRF imaging. The distribution data in-vitro showed that TTU of 131I-labeled IgG was higher than that of 131I-labeled Atezolizumab at any time point. Conclusion: Non-specific IgG may not be suitable as a control for Atezolizumab in comparing tumor PD-L1 expression in nude mice via labeled antibody optical imaging under certain circumstances.

Pathogenicity of functionally activated PD-1+CD8+ cells and counterattacks by muscular PD-L1 through IFNγ in myositis.

Programmed-cell-death 1 (PD-1) expression is associated not only with T-cell activation but with exhaustion. Specifically, PD-1+ T cells present an exhausted phenotype in conditions of chronic antigen exposure, such as tumor microenvironments and chronic viral infection. However, the immune status regarding exhaustion of PD-1+CD8+ T cells in chronic autoimmune diseases including idiopathic inflammatory myopathies (IIMs) remains unclear. We aimed to clarify the role of PD-1+CD8+ T cells and PD-1 ligand (PD-L1) in IIMs. We showed that PD-1+ cells infiltrated into PD-L1-expressing muscles in patients with IIMs and immune checkpoint inhibitor-related myopathy. According to the peripheral blood immunophenotyping, the PD-1+CD8+ cell proportions were comparable between the active and inactive patients. Of note, PD-1+CD8+ cells in the active patients highly expressed cytolytic molecules, indicating their activation, while PD-1-CD8+ cells expressed low levels of cytolytic molecules in the active and inactive patients. A part of PD-1+CD8+ cells expressed the HMG-box transcription factor TOX highly and presented the exhausted phenotype in the active patients. Among PD-1+CD4+ T cells, PD-1highCXCR5-CD45RO+CD4+ peripheral helper T cells were increased in the active patients. PD-L1-deficient mice developed severer C-protein-induced myositis (CIM), a model of polymyositis, with abundant infiltration of PD-1+CD8+ cells expressing cytolytic molecules than wild-type mice, indicating pathogenicity of the PD-1+CD8+ cells and the protective role of PD-L1. The deficiency of IFNγ, a general PD-L1-inducer, impaired muscular PD-L1 expression and exacerbated CIM, indicating IFNγ-dependent muscular PD-L1 regulation. IFNγ-induced PD-L1 on myotubes was protective in an established muscle injury model. In conclusion, PD-1+CD8+ T cells rather than PD-1-CD8+ T cells were a pathogenic subset of IIMs. Muscular PD-L1 was regulated by IFNγ and exerted protective properties in IIMs.

Difference between Keratinized- and Non-Keratinized-Originating Epithelium in the Process of Immune Escape of Oral Squamous Cell Carcinoma.

Immune checkpoint inhibitors (ICIs), including anti-programmed cell death 1 ligand 1 (PD-L1) antibodies, are significantly changing treatment strategies for human malignant diseases, including oral cancer. Cancer cells usually escape from the immune system and acquire proliferative capacity and invasive/metastatic potential. We have focused on the two immune checkpoints, PD-1/PD-L1 and CD47/SIRPα, in the tumor microenvironment of oral squamous cell carcinoma (OSCC), performed a retrospective analysis of the expression of seven immune-related factors (PD-L1, PD-1, CD4, CD8, CD47, CD56 and CD11c), and examined their correlation with clinicopathological status. As a result, there were no significant findings relating to seven immune-related factors and several clinicopathological statuses. However, the immune checkpoint-related factors (PD-1, PD-L1, CD47) were highly expressed in non-keratinized epithelium-originated tumors when compared to those in keratinized epithelium-originated tumors. It is of interest that immunoediting via immune checkpoint-related factors was facilitated in non-keratinized sites. Several researchers reported that the keratinization of oral mucosal epithelia affected the immune response, but our present finding is the first study to show a difference in tumor immunity in the originating epithelium of OSCC, keratinized or non-keratinized. Tumor immunity, an immune escape status of OSCC, might be different in the originating epithelium, keratinized or non-keratinized.

PD-L1 and CD8+ T cell evaluation in breast cancers and their correlation with clinicopathological parameters.

OBJECTIVE: To determine the immunohistochemical expression of Programmed cell Death Ligand 1 and intratumoural cluster of differentiation-8-positive T lymphocyte count in primary breast cancer cases, and to ascertain their association with different clinicopathological parameters. Methods: The cross-sectional study was conducted at the Pakistan Navy Station Shifa Hospital, Karachi, from January 2020 to December 2021, and comprised patients of breast cancer regardless of age. Representative tissue blocks, both prospective and from the 2019 institutional archives, were exposed to immunohistochemical staining with Programmed cell Death Ligand 1 and intratumoural cluster of differentiation-8-positive T lymphocyte antibodies. Pathological and clinical records were used for assessing clinicopathological parameters. Data was analysed using SPSS 23. RESULTS: Of the 70 women with mean age 52.04±12.54 years, 30(42.9%) expressed high Programmed cell Death Ligand 1 positivity, and 55(78.6%) revealed low intratumoural cluster of differentiation-8-positive T lymphocyte count, while 23 (32.9%), had both Programmed cell Death Ligand 1 high positivity and low intratumoural cluster of differentiation-8-positive T lymphocyte count. The association between Programmed cell Death Ligand 1 and intratumoural cluster of differentiation- 8-positive T lymphocytes was not significant (p=0.813). A strong significant association was observed between Programmed cell Death Ligand 1 expression and progesterone receptor negative status (p=0.008). No significant association was observed with any other clinicopathological parameter. CONCLUSIONS: Programmed cell Death Ligand 1 high positivity and low intratumoural cluster of differentiation-8-positive T lymphocyte count were together observed in one-third of the breast cancer cases. A strong significant association existed between Programmed cell Death Ligand 1 high positivity and progesterone receptor negative status.

Effectiveness of PD1/PD-L1 combined with anti-angiogenic drugs in patients with advanced nonsmall cell lung cancer: A systematic review and meta-analysis.

Background: Protein-1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) therapy have become an important treatment approach for patients with advanced nonsmall cell lung cancer (NSCLC), but primary or secondary resistance remains a challenge for some patients. PD-1/PD-L1 combined with anti-angiogenic drugs (AAs) in NSCLC patients have potential synergistic effects, and the survival benefit may vary based on a treatment order. To investigate the efficacy of PD-1/PD-L1 combined with AAs as the treatment for patients with advanced NSCLC. Materials and Methods: We comprehensively searched EMBASE, PubMed, Web of Science, CNKI, VIP, and Wanfang databases from January 2017 to September 2022. The Cochrane risk bias tool evaluated the quality of included randomized clinical trials. Newcastle-Ottawa-Scale score was used to evaluate the quality of retrospective studies. Publication bias was evaluated by funnel plot, Begg's test, and Egger's test. Results: Seventeen articles were finally selected, involving 5182 patients. Meta-analysis results showed that PD1/PD-L1 combined with AAs therapy significantly improved progression-free survival (PFS) (hazard ratio [HR] = 0.61, 95% confidence interval [CI]: 0.50-0.75, P < 0.00001), overall survival (OS) (HR = 0.79, 95% CI: 0.71-0.88, P < 0.00001), and objective response rate (ORR) (risk ratio = 0.88, 95% CI: 0.81-0.96, P = 0.004), with the statistically significant difference. The sensitivity analysis demonstrated the robustness of the PFS, ORR, and OS. Conclusion: The combination of PD-1/PD-L1 inhibitors with AAs in treating advanced patients has exhibited notable therapeutic advantages when contrasted with monotherapy. Specifically, the administration of PD-1/PD-L1 inhibitors in conjunction with AAs, or sequential treatment involving PD-1/PD-L1 followed by AAs, has shown enhanced therapeutic efficacy in this patient population.

Efficacy and safety of pembrolizumab monotherapy in patients with advanced thyroid cancer in the phase 2 KEYNOTE-158 study.

BACKGROUND: The authors report results from the thyroid carcinoma cohort of the multicohort phase 2 KEYNOTE-158 study (NCT02628067), which evaluated pembrolizumab monotherapy in patients with previously treated cancers. METHODS: Eligible patients had histologically and/or cytologically confirmed papillary or follicular thyroid carcinoma, failure of or intolerance to prior therapy, and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Patients received pembrolizumab (200 mg) every 3 weeks for up to 35 cycles. The primary end point was objective response rate (ORR) per RECIST v1.1 by independent central review. RESULTS: A total of 103 patients were enrolled and received pembrolizumab. Median duration from first dose to data cutoff (October 5, 2020) was 49.4 (range, 43.9-54.9) months. ORR was 6.8% (95% confidence interval [CI], 2.8%-13.5%), and median duration of response was 18.4 (range, 4.2-47.2+) months. ORR was 8.7% (95% CI, 2.4%-20.8%) among patients with programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥1 (n = 46) and 5.7% (95% CI, 1.2%-15.7%) among patients with PD-L1 CPS <1 (n = 53). Median overall survival and progression-free survival were 34.5 (95% CI, 21.2 to not reached) and 4.2 (95% CI, 3.9-6.2) months, respectively. Treatment-related adverse events occurred in 69.9% of patients (grade 3-5, 14.6%). CONCLUSIONS: Pembrolizumab demonstrated manageable toxicity and durable antitumor activity in a small subset of patients with advanced thyroid cancer. These results provide evidence of modest antitumor activity in this setting regardless of tumor PD-L1 expression. Future studies evaluating immune checkpoint inhibitors in patients with differentiated thyroid cancer should focus on biomarker-driven patient selection or combination of immune checkpoint inhibitors with other agents, in order to achieve higher response rates than observed in this study.

Expression pattern of PD-1/PD-L1 in primary liver cancer with clinical correlation.

Immunotherapy, including ICIs, has emerged as an invaluable treatment option for advanced PLC. Nevertheless, the expression patterns of PD-L1 and PD-1 in PLC remain incompletely understood. In this study, the expression pattern and clinical correlation of PD-L1 and PD-1 were analysed in 5245 PLC patients. The positivity rates of PD-L1 and PD-1 were very low in the patient PLCs, but the positivity rates of PD-L1 and PD-1 were higher in the ICC and cHCC-ICC than in HCC. The expression of PD-L1 and PD-1 correlated with the malignant phenotypes and clinicopathological characteristics of PLC. Interestingly, PD-1 positivity might serve as an independent prognostic factor. Based on a systematic analysis of a large amount of PLC tissues, we proposed a novel classification of PD-1/PD-L1 expression in HCC and ICC. In light of this stratification, we observed a close correlation between PD-L1 levels and PD-1 expression in HCC and ICC.

PD-L1 Exon 3 Is a Hidden Switch of Its Expression and Function in Oral Cancer Cells.

The interaction between programmed cell death 1 ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) protects tumor cells from immune surveillance. PD-L1 exon 3 is a potential alternative exon and encodes an Ig variable (IgV) domain. Here, we found that a lack of exon 3 leads to the significant loss of cellular membrane locations and the dramatically reduced protein expression of PD-L1, indicating that PD-L1 exon 3 is essential for its protein expression and translocation to the cell membrane. Notably, oral cancer cells show almost no exon 3 skipping to ensure the expression of the full-length, functional PD-L1 protein. We discovered two key exonic splicing enhancers (ESEs) for exon 3 inclusion. Two efficient antisense oligonucleotides (ASOs) were identified to block these two ESEs, which can significantly trigger exon 3 skipping and decrease the production of full-length, functional PD-L1 on the surface of cancer cells. Treatment of oral cancer cells with these ASOs significantly enhanced immune cells' suppression of cancer cell proliferation. Surprisingly, these two ASOs also significantly inhibited cell growth and induced cell pyroptosis in oral cancer cells. Altogether, the results of our study demonstrate the pivotal roles of exon 3 in PD-L1 expression and provide a novel anti-PD-L1 method.

[Consistency comparison of programmed cell death 1-ligand 1 in different immuno-histochemical staining methods].

OBJECTIVE: To compare the consistency of programmed cell death 1-ligand 1 (PD-L1, clone E1L3N, 22C3, SP263) in different immunohistochemical staining methods. METHODS: The first step was to select the optimal process: The PD-L1(clone E1L3N) antibody recommended process, self-built process ①, self-built process ② and self-built process ③ were used to perform immunohistochemical staining in 5 cases of tonsil tissue. The quality of all slides was scored by expert pathologists (0-6 points). The process with the highest score was selected. The second step was to compare the consistency between the optimal procedure and the two standard procedures. Thirty-two cases of lung non-small cell carcinoma diagnosed by pathology in Peking University First Hospital in the past two years were randomly selected. The 32 cases were stained in parallel with the SP263 and 22C3 standard procedures, and all stained slides were scored by specialized pathologists for tumor proportion score (TPS). The scoring results were grouped according to < 1%, ≥1% to < 10%, ≥10% to < 50%, and ≥50%. The consistency of PD-L1 detection antibody clone E1L3N and 22C3, E1L3N and SP263 staining results was analyzed. RESULTS: Tonsil stained slides scores (0-6 points) were as follows: The recommended protocol was 5, 5, 5, 5 and 5. The self-built process ① was 5, 6, 6, 5 and 6. The self-built process ② was 4, 4, 4, 4 and 4.The self-built process ③ was 3, 3, 3, 3 and 3. The self-built process ① was the best with the highest score. The TPSs of 32 non small cell lung carcinoma (NSCLC) cases were as follows: Of self-built process ①, 6 cases were lower than 1%, 5 cases were from 1% to 10%, 10 cases were from 10% to 50%, and 11 cases were higher than 50%; of 22C3 standard procedure, 5 cases were lower than 1%, 3 cases were from 1% to 10%, 13 cases were from 10% to 50%, 11 cases were higher than 50%; of SP263 standard procedure, 7 cases were lower than 1%, 4 cases were from 1% to 10%, 11 cases were from 10% to 50%, 10 cases were higher than 50%. The results of the consistency test were as follows: The κ value for self-built process ① and 22C3 standard procedure was 0.736 (P < 0.001), the agreement was good; the κ value for self-built process ① and SP263 standard procedure was 0.914 (P < 0.001), the agreement was very good. CONCLUSION: The immunostaining using PD-L1(E1L3N) with validated self-built staining protocol ① by Ventana Benchmark GX platform can obtain high quality of slides, and the TPSs based on these slides are in good agreement with 22C3 and SP263 standard procedures.

[Thoracic SMARCA4-deficient undifferentiated tumor-pathological diagnosis and combined immune checkpoint inhibitor treatment].

We explored clinicopathological features and treatment strategies for thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT). Thoracic SMARCA4-UT is a new entity recently acknowledged in the 2021 edition of World Health Organization Classification of Thoracic Tumors, and doctors are relatively unfamiliar with its diagnosis, treatment, and prognosis. Taking a case of SMARCA4-UT treated in Peking University First Hospital as an example, this multi-disciplinary discussion covered several hot issues on diagnosing and treating thoracic SMARCA4-UT, including histological features, immu- nohistochemical and molecular phenotype, immune checkpoint inhibitor (ICI) therapy, and pathological assessment of neoadjuvant therapy response. The patient was an older man with a long history of smoking and was admitted due to a rapidly progressing solid tumor in the lower lobe of the right lung. Histologically, tumor cells were epithelioid, undifferentiated, diffusely positive for CD34, and partially positive for SALL4.The expression of BRG1 protein encoded by SMARCA4 gene was lost in all of tumor cells, and next-generation sequencing(NGS)confirmed SMARCA4 gene mutation (c.2196T>G, p.Y732Ter). The pathological diagnosis reached as thoracic SMARCA4-UT, and the preoperative TNM stage was T1N2M0 (ⅢA). Tumor proportion score (TPS) detected by immunohistochemistry of programmed cell death 1-ligand 1 (PD-L1, clone SP263) was 2%. Tumor mutation burden (TMB) detected by NGS of 1 021 genes was 16. 3/Mb. Microsatellite detection showed the tumor was microsatellite stable (MSS). Neo-adjuvant therapy was implemented with the combined regimen of chemotherapy and ICI. Right lower lobectomy was performed through thoracoscopy after the two weeks' neoadjuvant. The pathologic assessment of lung tumor specimens after neoadjuvant therapy revealed a complete pathological response (CPR). The post-neoadjuvant tumor TNM stage was ypT0N0M0. Then, five cycles of adjuvant therapy were completed. Until October 2022, neither tumor recurrence nor metastasis was detected, and minimal residual disease (MRD) detection was negative. At present, it is believed that if BRG1 immunohistochemical staining is negative, regardless of whether SMARCA4 gene mutation is detected, it should be classified as SMARCA4-deficient tumors. SMARCA4-deficient tumors include a variety of carcinomas and sarcomas. The essential criteria for diagnosing SMARCA4-UT includes loss of BRG1 expression, speci-fic histological morphology, and exclude other common thoracic malignant tumors with SMARCA4-deficiency, such as squamous cell carcinoma, adenocarcinoma and large cell carcinoma. SMARCA4-UT is a very aggressive malignant tumor with a poor prognosis. It has almost no targeted therapy mutations, and little response to chemotherapy, but ICI is currently the only effective drug. The successful diagnosis and treatment for this case of SMARCA4-UT should enlighten significance for various kinds of SMARCA4-deficient tumors.

Elevated expression of B7 homolog 4 is associated with disease progression in upper urinary tract urothelial carcinoma.

BACKGROUND: B7 homolog 4 (B7-H4) is a negative regulator of immune responses, but its immunoregulatory role in the tumor microenvironment of upper urinary tract urothelial carcinoma (UTUC) remains unclear. METHODS: We measured the immunohistochemical expression of B7-H4, CD8 and T cell intracellular antigen 1 (TIA-1), a marker of activated CD8, in 133 patients with UTUC who underwent nephroureterectomy. We also studied the relationship between B7-H4, CD8 and TIA-1 expression and clinicopathological characteristics. RESULTS: B7-H4 was mainly expressed on the surface in tumor cells, while CD8 and TIA-1 were often expressed in tumor-infiltrating lymphocytes. Elevated expression of B7-H4 in tumor cells was associated with a poorer histological grade, higher pT stage, regional lymph node metastasis, lymphovascular invasion, poorer response of recurrent metastatic lesions to systemic chemotherapy and shorter overall survival. Expression of CD-8 or TIA-1 alone did not correlate directly with clinicopathological characteristics, but among the patients with higher B7-H4 expression in the primary tumors, those with higher CD8 or TIA-1 expression had a better response to systemic chemotherapy, and longer survival, than these with lower CD8 or TIA-1 expression. Cox multivariate regression analysis revealed that higher expression of B7-H4 was associated with shorter overall survival. CONCLUSIONS: These findings suggest that B7-H4 expression in the tumor microenvironment influences the progression of UTUC through cancer immunity and metabolic activity. Tumor cell-associated B7-H4 might be a potential target for cancer immunotherapies.

Research progress in the role of CD38 in clinical tumor treatment. / CD38åœ¨ä¸´åºŠè‚¿ç˜¤æ²»ç–—ä¸­ä½œç”¨çš„ç ”ç©¶è¿›å±•.

Tumor is one of the ten leading causes of death in the world. Traditional tumor treatments include surgery, radiation therapy, and chemotherapy. With the development of immune checkpoint blockade therapy targeting the programmed death 1/programmed cell death 1 ligand 1 (PD-1/PD-L1) axis, the number of cancers in solid tumors has increased. Changes in the immunometabolic microenvironment have been shown to be important regulators of innate suppression of immune cell function and acquired resistance to immunotherapy. As a new target, CD38 is an enzyme that produces immunosuppressive metabolites (such as adenosine), which can be used in combination with immunotherapy to improve the clinical efficacy of tumor therapy, and can also be used as an indicator for understanding tumor immunotherapy response.

The polymorphism rs975484 in the protein arginine methyltransferase 1 gene modulates expression of immune checkpoint genes in hepatocellular carcinoma.

Protein arginine methyltransferase 1 (PRMT1) is a key regulator of hepatic immune responses. Recently, we reported that PRMT1 regulates the tumor immune response in hepatocellular carcinoma (HCC). Here we found that PRMT1 expression in human HCC correlates with that of programmed cell death 1 ligand 1 (PD-L1), PD-L2, and other checkpoint genes. PRMT1 deletion in mice reduced PD-L1 and PD-L2 expression in tumors and reduced the efficiency of PD-1 antibody treatment in a diethylnitrosamine-induced HCC mouse model, suggesting that PRMT1 regulates the hepatic immune checkpoint. Mice had reduced PD-L1 and PD-L2 expression when PRMT1 was specifically deleted in tumor cells or macrophages, but PRMT1 deletion in dendritic cells did not alter PD-L1 and PD-L2 expression. rs975484 is a common polymorphism in the human PRMT1 gene promoter, and we found that it alters PRMT1 expression in blood monocytes and tumor-associated macrophages in human HCC. PRMT1 expression was higher in individuals with a GG genotype than in individuals with a CC genotype, and heterozygous carriers had intermediate expression. Luciferase reporter assays indicated that this differential expression is due to an extra C/EBPß-binding site in the PRMT1 promoter of individuals carrying the minor G allele. The rs975484 genotype also correlated with PRMT1 target expression in HCC. Individuals with the GG genotype had significantly higher levels of the PRMT1 targets PD-L1, PD-L2, and VISTA than those with the CC genotype. We conclude that PRMT1 critically controls immune checkpoints in mice and humans and that the PRMT1 polymorphism rs975484 affects checkpoint gene expression in HCC.

Loss of NFKB1 Results in Expression of Tumor Necrosis Factor and Activation of Signal Transducer and Activator of Transcription 1 to Promote Gastric Tumorigenesis in Mice.

BACKGROUND & AIMS: Activity of nuclear factor κB transcription factors and signaling via signal transducer and activator of transcription (STAT) are frequently altered in gastric cancer cells. Mice lacking NFKB1 (Nfkb1-/- mice) develop invasive gastric cancer, and their gastric tissues have increased levels of cytokines, such as interleukin (IL) 6, IL22, IL11, and tumor necrosis factor (TNF), as well as increased activation of STAT1. We investigated whether these cytokines were required for STAT1 activation in gastric tissues of mice and critical for gastric tumorigenesis. METHODS: We crossed Nfkb1-/- mice with Il6-/-, Il22-/-, Il11Rα-/-, and Tnf-/- mice. Stomach tissues from compound mutant mice were analyzed by histology, immunoblotting, and RNA sequencing. Lymphoid, myeloid, and epithelial cells were isolated from stomachs, and the levels of cytokines were determined by flow cytometric analysis. RESULTS: Nfkb1-/- mice developed gastritis, oxyntic atrophy, gastric dysplasia, and invasive tumors, whereas Nfkb1-/-Stat1-/- mice did not, even when followed for as long as 2 years. The levels of Il6, Il11, Il22, and Tnf messenger RNA were increased in the body and antrum of the stomachs from Nfkb1-/- mice, from 3-6 months of age. However, Nfkb1-/-Il6-/-, Nfkb1-/-Il22-/-, and Nfkb1-/-Il11Rα-/- mice still developed gastric tumors, although the absence of IL11 receptor (IL11R) significantly reduced development of invasive gastric tumors. Stomachs from Nfkb1-/-Tnf-/- mice exhibited significantly less gastritis and oxyntic atrophy and fewer tumors than Nfkb1-/- mice. This correlated with reduced activation of STAT1 and STAT3 and fewer numbers of T cells and B cells infiltrating the gastric body. Loss of STAT1 or TNF significantly reduced expression of PD-L1 on epithelial and myeloid (CD11b+) cells in the gastric mucosa of Nfkb1-/- mice-indeed, to the levels observed on the corresponding cells from wild-type mice. CONCLUSIONS: In studies of gastric tumor development in knockout mice, we found that loss of NFKB1 causes increased expression of TNF in the stomach and thereby drives activation of STAT1, resulting in an inflammatory immune response and the development of gastric cancer. IL11R appears to be required for the progression of gastric tumors to the invasive stage. These findings suggest that inhibitors of TNF, and possibly also inhibitors of IL11/IL11Rα, might be useful in the treatment of gastric cancer.

Efficacies of programmed cell death 1 ligand 1 blockade in non-small cell lung cancer patients with acquired resistance to prior programmed cell death 1 inhibitor and development of diabetic ketoacidosis caused by two different etiologies: a retrospective case series.

The programmed cell death 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) axis is vital for immune resistance during tumor development, while PD-L1 inhibitors can also inhibit the PD-L1/B7-1 (CD80) interaction, indicating one of the molecular differences between PD-1 and PD-L1 inhibitors. However, the clinical benefits of PD-L1 inhibitors in patients previously treated with PD-1 inhibitors remain unknown. In this study, we retrospectively analyzed the clinical data of eight patients with non-small cell lung cancer who received the PD-L1 inhibitor atezolizumab and previously treated with the PD-1 inhibitor nivolumab. The median progression-free survival was 2.1 months (1.8-18.7 months), and 4 of 8 patients achieved at least stable disease. In two of these patients, atezolizumab treatment resulted in longer progression-free survival (PFS) compared with that of nivolumab. Conversely, one patient exhibited grade 4 diabetic ketoacidosis (DKA) within 2 weeks after the initial administration of atezolizumab. Another patient had developed type 1 diabetes mellitus (T1DM) during the prior nivolumab treatment and then developed DKA due to an infection after the initiation of atezolizumab. Both of them had high-risk human leukocyte antigen-DR/DQ types relevant to T1DM. These results demonstrate the potential efficacy of PD-L1 inhibitors to some tumors that have acquired resistance to PD-1 inhibitors and suggest that appropriate managements are required for not only a newly onset of T1DM but also blood glucose control after the development of T1DM during a reiteration of the PD-1/PD-L1 blockade.

Analysis of Several Pathways for Efficient Killing of Prostate Cancer Stem Cells: A Central Role of NF-κB RELA.

Prostate cancer is a common cause of death worldwide. Here, we isolated cancer stem cells (CSCs) from four adenocarcinomas of the prostate (Gleason scores from 3 + 3 up to 4 + 5). CSCs were characterized by the expression of the stem cell markers TWIST, the epithelial cell adhesion molecule (EPCAM), the transcription factors SNAI1 (SNAIL) and SNAI2 (SLUG) and cancer markers such as CD44 and prominin-1 (CD133). All investigated CSC populations contained a fraction highly positive for aldehyde dehydrogenase (ALDH) function and displayed robust expressions of programmed cell death 1 (PD-1) ligands. Furthermore, we investigated immunotherapeutic approaches but had no success even with the clinically used PD-1 inhibitor pembrolizumab. In addition, we studied another death-inducing pathway via interferon gamma signaling and detected high-level upregulations of human leukocyte antigen A (HLA-A) and beta 2-microglobulin (B2M) with only moderate killing efficacy. To examine further killing mechanisms in prostate cancer stem cells (PCSCs), we analyzed NF-κB signaling. Surprisingly, two patient-specific populations of PCSCs were found: one with canonical NF-κB signaling and another one with blunted NF-κB activation, which can be efficiently killed by tumor necrosis factor (TNF). Thus, culturing of PCSCs and analysis of respective NF-κB induction potency after surgery might be a powerful tool for optimizing patient-specific treatment options, such as the use of TNF-inducing chemotherapeutics and/or NF-κB inhibitors.

[Kidney injury associated with antitumor therapy: focus on the adverse events of modern immuno-oncological drugs].

Immune checkpoint inhibitors (ICIs), including cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) and programmed death protein 1 (PD-1) or its ligand (PD-L1), are a new generation of immuno-oncological drugs that to date have demonstrated efficacy in a number of malignancies. The mechanism of ICT inhibitors action consist in the potentiation of the immune response by eliminating the tumor cells inhibitory effect on the T-lymphocytes activation. However, excessive immune system activation can cause the development of a special class of immune-related adverse events (irAEs) involved a wide variety of organs and systems, including the kidneys. Despite the fact that immuno-mediated kidney injury caused by ICI therapy develops quite rarely, it can be serious and determine the patient's prognosis, which necessitates early diagnosis and timely start of treatment. In this regard, awareness of the manifestations of ICI-associated renal irAEs is particularly relevant not only for oncologists and for nephrologists, but for doctors of other specialties. In this review, we elucidated the main variants of immuno-mediated kidney injury caused by ICI therapy, discussed possible predictors and mechanisms of their development, and considers the general principles of diagnosis and management of patients according to the severity of irAEs.

Association of cancer progression with elevated expression of programmed cell death protein 1 ligand 1 by upper tract urothelial carcinoma and increased tumor-infiltrating lymphocyte density.

BACKGROUND: Increased expression of programmed cell death 1 ligand 1 (PD-L1) by tumor cells is thought to be a mechanism through which solid cancers promote immune tolerance. However, the association between PD-L1 expression and the prognosis of upper urinary tract urothelial carcinoma (UTUC) remains unknown. METHODS: We examined immunohistochemical PD-L1 expression and the tumor-infiltrating lymphocyte density (TILD) in 79 patients with UTUC who underwent nephroureterectomy. We classified the tumors into four types based on the combination of PD-L1 expression and TILD, and studied the clinicopathological characteristics of these four tumor types. RESULTS: Elevated expression of PD-L1 by tumor cells and a higher TILD were associated with a worse histological grade, higher pT stage, and higher peripheral blood neutrophil-to-lymphocyte ratio. Elevated expression of PD-L1 by tumor cells, a higher TILD, and type I, III, or IV tumors with elevated expression of either PD-L1 or TILD showed a positive correlation with poorer differentiation and local invasion. These three variables were associated with shorter progression-free survival and overall survival in univariate analysis, but only the latter was an independent determinant according to multivariate analysis. The patients who had type II tumors with lower PD-L1 expression and a lower TILD showed more favorable survival than the other three groups. CONCLUSIONS: These findings suggest that PD-L1 expression and TILs in the tumor microenvironment influence the progression of UTUC. Accordingly, it is important to understand the immunologic characteristics of the tumor microenvironment to develop more effective treatment strategies for this cancer.

Prognostic significance of pre- and post-treatment PD-L1 expression in patients with primary high-grade non-muscle-invasive bladder cancer treated with BCG immunotherapy.

PURPOSE: Programmed cell death-1 ligand-1 (PD-L1) expression has been associated with prognostic implications in urologic malignancies. We aimed to investigate prognostic significance of pre- and post-treatment PD-L1 expression in patients treated with BCG for high-grade non-muscle-invasive bladder cancer (NMIBC). METHODS: We reviewed a total of 141 high-grade NMIBC cases treated with transurethral resection + ≥ 6 BCG instillations between 2004 and 2017. PD-L1 immunohistochemistry (IHC) scoring was done on 0-3 scale, and cut-off for positive and high-level PD-L1 expression was set to ≥ 1% and ≥ 5% staining of tumor-infiltrating immune cells (IC), respectively. Clinicopathologic characteristics and oncologic outcomes [recurrence-free (RFS) and progression-free survival (PFS)] were compared, stratified by PD-L1 positivity. The prognostic role of PD-L1 was assessed using Kaplan-Meier, and univariate and multivariate Cox regression analyses. RESULTS: Pre-treatment, 46.2% and 6.8% of high-grade NMIBC demonstrated positive and high-level PD-L1 expression, respectively. Positive PD-L1 expression was associated with submucosal invasion and refractory-tumor recurrence. PD-L1 expression was not associated with RFS or PFS in regression analysis. Post-treatment, 55.1% and 11.6% of recurrent tumors demonstrated positive and high-level PD-L1 expression, respectively. Down-regulation of PD-L1 expression was noted in patients with refractory recurrence (p = 0.012). CONCLUSION: Pre-treatment PD-L1 expression was associated with unfavorable pathological features in primary high-grade NMIBC and its expression level after BCG immunotherapy was significantly decreased in patients with refractory recurrence. PD-L1 expression did not have prognostic value for PFS or RFS; therefore, further research is necessary to identify novel biomarkers for prediction of disease outcomes in high-grade NMIBC.

Induction of PD-L1 by Nitric Oxide via JNK Activation in A172 Glioblastoma Cells.

Glioblastoma comprises 54% of all the gliomas derived from glial cells and are lethally malignant tumors of the central nervous system (CNS). Glioma cells disrupt the blood-brain barrier, leading to access of circulating immune cells to the CNS. Blocking the interaction between programmed cell death 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) enhances T-cell responses against tumor cells, and inhibition of the PD-1/PD-L1 pathway is used as immunotherapy for cancer, including glioblastoma. Nitric oxide (NO) has multiple physiological roles, such as immune modulation and neural transmission in the CNS. Moreover, it has both tumor-promoting and tumor-suppressive functions. We examined the effects of NOC-18, an NO donor, on the expression of PD-L1 in A172 glioblastoma cells. NOC-18 increased PD-L1 expression in A172 glioblastoma cells. Moreover, this increase is regulated via the c-Jun N-terminal kinase pathway.