Engineering PD-1-targeted small protein variants for in vitro diagnostics and in vivo PET imaging

BACKGROUND

Programmed cell death 1 (PD-1) belongs to immune checkpoint proteins ensuring negative regulation of the immune response. In non-small cell lung cancer (NSCLC), the sensitivity to treatment with anti-PD-1 therapeutics, and its efficacy, mostly correlated with the increase of tumor infiltrating PD-1+ lymphocytes. Due to solid tumor heterogeneity of PD-1+ populations, novel low molecular weight anti-PD-1 high-affinity diagnostic probes can increase the reliability of expression profiling of PD-1+ tumor infiltrating lymphocytes (TILs) in tumor tissue biopsies and in vivo mapping efficiency using immune-PET imaging.

METHODS

We designed a 13 kDa β-sheet Myomedin scaffold combinatorial library by randomization of 12 mutable residues, and in combination with ribosome display, we identified anti-PD-1 Myomedin variants (MBA ligands) that specifically bound to human and murine PD-1-transfected HEK293T cells and human SUP-T1 cells spontaneously overexpressing cell surface PD-1.

RESULTS

Binding affinity to cell-surface expressed human and murine PD-1 on transfected HEK293T cells was measured by fluorescence with LigandTracer and resulted in the selection of most promising variants MBA066 (hPD-1 KD = 6.9 nM; mPD-1 KD = 40.5 nM), MBA197 (hPD-1 KD = 29.7 nM; mPD-1 KD = 21.4 nM) and MBA414 (hPD-1 KD = 8.6 nM; mPD-1 KD = 2.4 nM). The potential of MBA proteins for imaging of PD-1+ populations in vivo was demonstrated using deferoxamine-conjugated MBA labeled with 68Galium isotope. Radiochemical purity of 68Ga-MBA proteins reached values 94.7-99.3% and in vitro stability in human serum after 120 min was in the range 94.6-98.2%. The distribution of 68Ga-MBA proteins in mice was monitored using whole-body positron emission tomography combined with computerized tomography (PET/CT) imaging up to 90 min post-injection and post mortem examined in 12 mouse organs. The specificity of MBA proteins was proven by co-staining frozen sections of human tonsils and NSCLC tissue biopsies with anti-PD-1 antibody, and demonstrated their potential for mapping PD-1+ populations in solid tumors.

CONCLUSIONS

Using directed evolution, we developed a unique set of small binding proteins that can improve PD-1 diagnostics in vitro as well as in vivo using PET/CT imaging.

Surface PD-1 expression in T cells is suppressed by HNRNPK through an exonic splicing silencer on exon 3

OBJECTIVE

Immunotherapy targeting programmed cell death 1 (PDCD1 or PD-1) and its ligands has shown remarkable promise and the regulation mechanism of PD-1 expression has received arising attention in recent years. PDCD1 exon 3 encodes the transmembrane domain and the deletion of exon 3 produces a soluble protein isoform of PD-1 (sPD-1), which can enhance immune response by competing with full-length PD-1 protein (flPD-1 or surface PD-1) on T cell surface. However, the mechanism of PDCD1 exon 3 skipping is unclear.

METHODS

The online SpliceAid program and minigene expression system were used to analyze potential splicing factors involved in the splicing event of PDCD1 exon 3. The potential binding motifs of heterogeneous nuclear ribonucleoprotein K (HNRNPK) on exon 3 predicted by SpliceAid were mutated by site-directed mutagenesis technology, which were further verified by pulldown assay. Antisense oligonucleotides (ASOs) targeting the exonic splicing silencer (ESS) on PDCD1 exon 3 were synthesized and screened to suppress the skipping of exon 3. The alternative splicing of PDCD1 exon 3 was analyzed by semiquantitative reverse transcription PCR. Western blot and flow cytometry were performed to detect the surface PD-1 expression in T cells.

RESULTS

HNRNPK was screened as a key splicing factor that promoted PDCD1 exon 3 skipping, causing a decrease in flPD-1 expression on T cell membrane and an increase in sPD-1 expression. Mechanically, a key ESS has been identified on exon 3 and can be bound by HNRNPK protein to promote exon 3 skipping. Blocking the interaction between ESS and HNRNPK with an ASO significantly reduced exon 3 skipping. Importantly, HNRNPK can promote exon 3 skipping of mouse Pdcd1 gene as well.

CONCLUSIONS

Our study revealed a novel evolutionarily conserved regulatory mechanism of PD-1 expression. The splicing factor HNRNPK markedly promoted PDCD1 exon 3 skipping by binding to the ESS on PDCD1 exon 3, resulting in decreased expression of flPD-1 and increased expression of sPD-1 in T cells.

CDK12 inhibition upregulates ATG7 triggering autophagy via AKT/FOXO3 pathway and enhances anti-PD-1 efficacy in colorectal cancer

As the world's fourth most deadly cancer, colorectal cancer (CRC) still needed the novel therapeutic drugs and target urgently. Although cyclin-dependent kinase 12 (CDK12) has been shown to be implicated in the malignancy of several types of cancer, its functional role and mechanism in CRC remain largely unknown. Here, we found that suppression of CDK12 inhibited tumor growth in CRC by inducing apoptosis. And CDK12 inhibition triggered autophagy by upregulating autophagy related gene 7 (ATG7) expression. Inhibition of autophagy by ATG7 knockdown and chloroquine (CQ) further decreased cell viability induced by CDK12 inhibition. Further mechanism exploration showed that CDK12 interacted with protein kinase B (AKT) regulated autophagy via AKT/forkhead box O3 (AKT/FOXO3) pathway. FOXO3 transcriptionally upregulated ATG7 expression and autophagy when CDK12 inhibition in CRC. Level of CDK12 and p-FOXO3/FOXO3 ratio were correlated with survival in CRC patients. Moreover, CDK12 inhibition improved the efficacy of anti-programmed cell death 1(PD-1) therapy in CRC murine models by enhancing CD8 + T cells infiltration. Thus, our study founded that CDK12 inhibition upregulates ATG7 triggering autophagy via AKT/FOXO3 pathway and enhances anti-PD-1 efficacy in CRC. We revealed the roles of CDK12/FOXO3/ATG7 in regulating CRC progression, suggesting potential biomarkers and therapeutic target for CRC.

Immune signature of small bowel adenocarcinoma and the role of tumor microenvironment

In this editorial we comment on the article published "Clinical significance of programmed cell death-ligand expression in small bowel adenocarcinoma is determined by the tumor microenvironment". Small bowel adenocarcinoma (SBA) is a rare gastrointestinal neoplasm and despite the small intestine's significant surface area, SBA accounts for less than 3% of such tumors. Early detection is challenging and the reason arises from its asymptomatic nature, often leading to late-stage discovery and poor prognosis. Treatment involves platinum-based chemotherapy with a 5-fluorouracil combination, but the lack of effective chemotherapy contributes to a generally poor prognosis. SBAs are linked to genetic disorders and risk factors, including chronic inflammatory conditions. The unique characteristics of the small bowel, such as rapid cell renewal and an active immune system, contributes to the rarity of these tumors as well as the high intratumoral infiltration of immune cells is associated with a favorable prognosis. Programmed cell death-ligand 1 (PD-L1) expression varies across different cancers, with potential discrepancies in its prognostic value. Microsatellite instability (MSI) in SBA is associated with a high tumor mutational burden, affecting the prognosis and response to immunotherapy. The presence of PD-L1 and programmed cell death 1, along with tumor-infiltrating lymphocytes, plays a crucial role in the complex microenvironment of SBA and contributes to a more favorable prognosis, especially in the context of high MSI tumors. Stromal tumor-infiltrating lymphocytes are identified as independent prognostic indicators and the association between MSI status and a favorable prognosis, emphasizes the importance of evaluating the immune status of tumors for treatment decisions.

Molecular Imaging of PD-1 Unveils Unknown Characteristics of PD-1 Itself by Visualizing "PD-1 Microclusters"

Programmed cell death-1 (PD-1) is one of the most famous coinhibitory receptors that are expressed on effector T cells to regulate their function. The PD-1 ligands, PD-L1 and PD-L2, are expressed by various cells throughout the body at steady state and their expression was further regulated within different pathological conditions such as tumor-bearing and chronic inflammatory diseases. In recent years, immune checkpoint inhibitor (ICI) therapies with anti-PD-1 or anti-PD-L1 has become a standard treatment for various malignancies and has shown remarkable antitumor effects. Since the discovery of PD-1 in 1992, a huge number of studies have been conducted to elucidate the function of PD-1. Herein, this paper provides an overview of PD-1 biological findings and sheds some light on the current technology for molecular imaging of PD-1.

PD-L1-expressing cancer-associated fibroblasts induce tumor immunosuppression and contribute to poor clinical outcome in esophageal cancer

The programmed cell death 1 protein (PD-1)/programmed cell death ligand 1 (PD-L1) axis plays a crucial role in tumor immunosuppression, while the cancer-associated fibroblasts (CAFs) have various tumor-promoting functions. To determine the advantage of immunotherapy, the relationship between the cancer cells and the CAFs was evaluated in terms of the PD-1/PD-L1 axis. Overall, 140 cases of esophageal cancer underwent an immunohistochemical analysis of the PD-L1 expression and its association with the expression of the α smooth muscle actin, fibroblast activation protein, CD8, and forkhead box P3 (FoxP3) positive cells. The relationship between the cancer cells and the CAFs was evaluated in vitro, and the effect of the anti-PD-L1 antibody was evaluated using a syngeneic mouse model. A survival analysis showed that the PD-L1+ CAF group had worse survival than the PD-L1- group. In vitro and in vivo, direct interaction between the cancer cells and the CAFs showed a mutually upregulated PD-L1 expression. In vivo, the anti-PD-L1 antibody increased the number of dead CAFs and cancer cells, resulting in increased CD8+ T cells and decreased FoxP3+ regulatory T cells. We demonstrated that the PD-L1-expressing CAFs lead to poor outcomes in patients with esophageal cancer. The cancer cells and the CAFs mutually enhanced the PD-L1 expression and induced tumor immunosuppression. Therefore, the PD-L1-expressing CAFs may be good targets for cancer therapy, inhibiting tumor progression and improving host tumor immunity.

Is the CRAFITY score a superior predictor of prognosis and adverse events in hepatocellular carcinoma patients treated with locoregional-immunotherapy?

BACKGROUND

The level of C‑reactive protein (CRP) and alpha‑fetoprotein (AFP) in immunotherapy (CRAFITY) score was associated with the prognosis of hepatocellular carcinoma (HCC) patients treated with immunotherapy. Based on the CRAFITY score, this study aimed to investigate the efficacy and safety of locoregional-immunotherapy for treating HCC patients.

METHODS

HCC patients who received locoregional-immunotherapy were consecutively recruited at Sun Yat-sen University Cancer Center in 2019. CRAFITY 0 score was defined as the AFP level below 100 ng/ml and a CRP level of less than 1 mg/dl, CRAFITY 1 score was defined as the AFP level of at least 100 ng/ml or the CRP level of at least 1 mg/dl, and CRAFITY 2 score was defined as both the AFP level over 100 ng/ml and the CRP level of more than 1 mg/dl. The primary outcomes were progression-free survival (PFS) and overall survival (OS). The second outcomes were tumor response rate and treatment-related adverse events (AEs).

RESULTS

The median PFS for HCC patients with the CRAFITY 0 score was not estimable. The PFS was 11.0 months [95% confidence interval (CI) 7.2-14.9] and 6.0 months (95% CI 4.2-7.8) for patients with CRAFITY 1 and 2 scores, respectively, with a significant difference between the two groups (p < 0.001). HCC patients with CRAFITY 0, 1, and 2 scores had 3 years OS rates of 63.8%, 60.8%, and 32.1%, respectively, with statistical differences among the three groups (p < 0.001). Patients with the CRAFITY 2 score were more likely to experience fever than those with other scores (p < 0.05). A greater CRAFITY score was correlated with a higher incidence of grade 3 and above liver injury (p < 0.01).

CONCLUSIONS

The CRAFITY score is a superior predictor of prognosis and treatment-related AEs in HCC patients treated with locoregional-immunotherapy.

The immune checkpoint protein PD-1: Its emerging regulatory role in memory T cells

Immunological memory helps the body rapidly develop immune defense when it re-encounters a bacterial or viral strain or encounters a similar mutation in healthy cells. The immune checkpoint molecule programmed cell death 1 (PD-1) influences memory T cell differentiation. However, the mechanism by which PD-1 regulates the development and maintenance of memory T cells and its impact on memory T cells function remain unclear. In this review, we first discuss the structure and function of PD-1 and then summarize the roles of PD-1 as a marker of tumor memory T cells and in tumor immunotherapy. We also discuss the potential mechanisms through which PD-1 regulates memory T cells development and maintenance during immune diseases such as viral infection-mediated diseases, psoriasis, and rheumatoid arthritis, and list the effects of PD-1 on memory T cells in pregnancy and their function in maternal-fetal immune balance. A complete understanding of how PD-1 influences the development, maintenance, and function of memory T cells will provide new insights into the prevention and treatment of immune-related diseases.

Stereotactic body radiotherapy combined with sintilimab in patients with recurrent or oligometastatic hepatocellular carcinoma: A phase II clinical trial

BACKGROUND

Stereotactic body radiotherapy (SBRT) and programmed cell death 1 inhibitors have shown potential in treating hepatocellular carcinoma (HCC) in retrospective studies.

AIM

To evaluate the efficacy of combining SBRT with sintilimab for patients with recurrent or oligometastatic HCC.

METHODS

This trial involved patients with recurrent or oligometastatic HCC intravenously treated with SBRT plus sintilimab every 3 wk for 12 mo or until disease progression. The primary endpoint was progression-free survival (PFS).

RESULTS

Twenty-five patients were enrolled from August 14, 2019, to August 23, 2021. The median treatment duration was 10.2 (range, 0.7-14.6) months. SBRT was delivered at a median dose of 54 (range, 48-60) Gy in 6 (range, 6-10) fractions. The median follow-up time was 21.9 (range, 10.3-39.7) mo, and 32 targeted lesions among 25 patients were evaluated for treatment response according to the Response Evaluation Criteria in Solid Tumors version 1.1. The median PFS was 19.7 mo [95% confidence interval (CI): 16.9-NA], with PFS rates of 68% (95%CI: 52-89) and 45.3% (95%CI: 28-73.4) at 12 and 24 mo, respectively. The median overall survival (OS) was not reached, with OS rates of 91.5% (95%CI: 80.8-100.0) and 83.2% (95%CI: 66.5-100.0) at 12 and 24 mo, respectively. The 1- and 2-year local control rate were 100% and 90.9% (95%CI: 75.4%-100.0%), respectively. The confirmed objective response rate and disease control rate was 96%, and 96%, respectively. Most adverse events were graded as 1 or 2, and grade 3 adverse events were observed in three patients.

CONCLUSION

SBRT plus sintilimab is an effective, well-tolerated treatment regimen for patients with recurrent or oligometastatic HCC.

Association of programmed cell death 1 (PD-1) gene polymorphism (rs10204525) with COVID-19 severity and mortality: A case-control study in the Iranian population

BACKGROUND

Programmed cell death 1 (PD-1), as a negative immune regulator, regulates the activation of T cells and maintains the immune system's homeostasis. Previous studies suggest that the effective immune response against COVID-19 contributes to the outcome of the disease. The present study aims to evaluate whether the PD-1 rs10204525 polymorphism is associated with PDCD-1 expression and COVID-19 severity and mortality in the Iranian population.

METHODS

The PD-1 rs10204525 was genotyped in 810 COVID-19 patients and 164 healthy individuals as a control group using Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Moreover, we assessed the expression of PDCD-1 in peripheral blood nuclear cells by real-time PCR.

RESULTS

Regarding disease severity and mortality, no significant differences were detected between study groups in alleles and genotypes frequency distribution under different inheritance models. We found that the expression of PDCD-1 was significantly lower in COVID-19 patients with AG and GG genotypes than in the control group. Regarding disease severity, mRNA levels of PDCD-1 were significantly lower in moderate and critical patients carrying AG genotype than in control (P = 0.005 and P = 0.002, respectively) and mild (P = 0.014 and P = 0.005, respectively) individuals. Additionally, the severe and critical patients with GG genotype displayed a significantly lower level of PDCD-1 compared with the control (P = 0.002 and P < 0.001, respectively), mild (P = 0.004 and P < 0.001, respectively), and moderate (P = 0.014 and P < 0.001, respectively) ones. Regarding disease mortality, the expression of PDCD-1 was significantly lower in non-survivor COVID-19 patients with GG genotype than in survivors.

CONCLUSION

Considering the lack of significant differences in PDCD-1 expression in different genotypes in the control group, lower expression of PDCD-1 in COVID-19 patients carrying the G allele suggests the impact of this single-nucleotide polymorphism on the transcriptional activity of PD-1.

Adjuvant anti-PD-1 antibody for hepatocellular carcinoma with high recurrence risks after hepatectomy

BACKGROUND AND PURPOSE

The clinical role of postoperative adjuvant therapy in hepatocellular carcinoma (HCC) is still unclear. The purpose of our study was to explore the clinical value of postoperative adjuvant anti-programed cell death 1 antibody (PA-PD-1) on the prognosis of HCC patients with high relapse risks after surgery.

PATIENTS AND METHODS

Data of consecutive HCC patients with high recurrence risks treated with liver resection at our center during January 2019 and March 2021 were prospectively collected. Baseline differences were balanced between HCC patients with (PA-PD-1 group) or without PA-PD-1 (non-PD-1 group) after hepatectomy by propensity-score matching (PSM). Between these two groups, we compared overall survival (OS) and recurrence-free survival (RFS). Independent prognostic risk factors for OS and RFS were confirmed by Cox regression analysis, and subgroup analysis was also performed.

RESULTS

47 pairs of patients with or without PD-1 treatment after hepatectomy were matched. After PSM, the 1-year and 2-year RFS was 58.4% and 44.1% in the PA-PD-1 group, and 34.0% and 21.3% in the non-PD-1 group (p = 0.008). The OS at 1 year and 2 years was 91.2% and 91.2% in the PA-PD-1 group, compared with 85.1% and 61.7% in the non-PD-1 group (p = 0.024). Multivariable analyses demonstrated that PA-PD-1 was an independent protective predictor associated with RFS and OS. Through subgroup analysis, we concluded that HCC patients with portal venous tumor thrombus (PVTT) or tumor size ≥ 5 cm significantly benefited from PA-PD-1 therapy in RFS and OS.

CONCLUSIONS

Adjuvant anti-PD-1 antibody can effectively improve the survival outcomes of HCC patients with high relapse risks after hepatectomy in this prospective observational study. This finding should be confirmed by results of the ongoing phase 3 randomized controlled trials.

Cancer immunotherapy by immune checkpoint blockade and its advanced application using bio-nanomaterials

Cancer is the second leading cause of death worldwide. Traditional approaches, such as surgery, chemotherapy, and radiotherapy have been the main cancer therapeutic modalities in recent years. Cancer immunotherapy is a novel therapeutic modality that potentiates the immune responses of patients against malignancy. Immune checkpoint proteins expressed on T cells or tumor cells serve as a target for inhibiting T cell overactivation, maintaining the balance between self-reactivity and autoimmunity. Tumors essentially hijack the immune checkpoint pathway in order to survive and spread. Immune checkpoint inhibitors (ICIs) are being developed as a result to reactivate the anti-tumor immune response. Recent advances in nanotechnology have contributed to the development of successful, safe, and efficient anticancer drug systems based on nanoparticles. Nanoparticle-based cancer immunotherapy overcomes numerous challenges and offers novel strategies for improving conventional immunotherapies. The fundamental and physiochemical properties of nanoparticles depend on various cancer therapeutic strategies, such as chemotherapeutics, nucleic acid-based treatments, photothermal therapy, and photodynamic agents. The review discusses the use of nanoparticles as carriers for delivering immune checkpoint inhibitors and their efficacy in cancer combination therapy.

Analysis of PD-1, PD-L1, and T-cell infiltration in angiosarcoma pathogenetic subgroups

Angiosarcoma (AS) is a rare malignancy with a poor prognosis. It can develop spontaneously or due to previous radiotherapy (RT), ultraviolet (UV) radiation, or lymphoedema (Stewart Treves AS). Novel therapeutic approaches are needed, but progress is hindered because of the heterogeneity and rarity of AS. In order to explore the potential of immune checkpoint inhibition (ICI), we investigated the protein expression of programmed cell death 1 (PD-1), programmed death-ligand 1 (PD-L1), and CD8 + T cells in 165 AS cases in relation to AS subgroups based on clinical classification and in relation to whole-genome methylation profiling based clusters (A1, A2, B1, B2). High PD-L1 and PD-1 expression were predominantly shown in UV-associated, visceral, and soft tissue AS. RT-associated AS showed predominantly high PD-1 expression. CD8 + T cell infiltration was present in the majority of AS samples. Within the UV-associated AS, two different clusters can be distinguished by DNA methylation profiling. Cases in cluster A1 showed higher PD-1 (p = 0.015), PD-L1 (p = 0.015), and CD8 + T cells (p = 0.008) compared to those in cluster B2, suggesting that these UV-AS tumors are more immunogenic than B2 tumors showing a difference even within one subgroup. In soft tissue AS, combined PD-1 and PD-L1 expression showed a trend toward poor survival (p = 0.051), whereas in UV-associated AS, PD-1 expression correlated with better survival (p = 0.035). In conclusion, we show the presence of PD-1, PD-L1, and CD8 + T cells in the majority of AS but reveal differences between and within AS subgroups, providing prognostic information and indicating to be predictive for ICI.

Sulforaphane enhances the antitumor response of chimeric antigen receptor T cells by regulating PD-1/PD-L1 pathway

BACKGROUND

Chimeric antigen receptor T (CAR-T) cell therapy has limited effects in the treatment of solid tumors. Sulforaphane (SFN) is known to play an important role in inhibiting tumor growth, but its effect on CAR-T cells remains unclear. The goal of the current study was to determine whether combined CAR-T cells and SFN could provide antitumor efficacy against solid tumors.

METHODS

The effect of combined SFN and CAR-T cells was determined in vitro using a co-culture system and in vivo using a xenograft mouse model. We further validated the effects of combination therapy in patients with cancer.

RESULTS

In vitro, the combination of SFN and CAR-T cells resulted in enhanced cytotoxicity and increased lysis of tumor cells. We found that SFN suppressed programmed cell death 1 (PD-1) expression in CAR-T cells and potentiated antitumor functions in vitro and in vivo. As a ligand of PD-1, programmed cell death ligand 1 (PD-L1) expression was also decreased in tumor cells after SFN treatment. In addition, β-TrCP was increased by SFN, resulting in higher activation of ubiquitination-mediated proteolysis of PD-L1, which induced PD-L1 degradation. The combination of SFN and CAR-T cell therapy acted synergistically to promote better immune responses in vivo compared with monotherapy. In clinical treatments, PD-1 expression was lower, and proinflammatory cytokine levels were higher in patients with various cancers who received CAR-T cells and took SFN orally than that in the control group.

CONCLUSION

SFN improves the cytotoxicity of CAR-T cells by modulating the PD-1/PD-L1 pathway, which may provide a promising strategy for the combination of SFN with CAR-T cells for cancer immunotherapy.

PD1/PDL1 expression is associated with increased TIM3 expression and tumor-infiltrating T lymphocytes in fibroblastic tumors

PURPOSE

The combined therapy of inhibiting T cell immunoglobulin domain and mucin domain 3 (TIM3) and programmed cell death 1/programmed death-ligand 1 (PD1/PDL1) has shown encouraging therapeutic effects in some solid tumors. However, the expression of PD1/PDL1 and TIM3 in fibroblastic tumors is ill defined, which has limited the application of these immune checkpoint inhibitors in such tumors.

METHODS

Immunostaining of 68 tissue microarray cores of fibroblastic tumors, including intermediate dermatofibrosarcoma protuberans and malignant myxofibrosarcoma and adult-type fibrosarcoma, was used to determine the expression of PD1, PDL1 and TIM3, as well as their relationship with the accumulation of tumor-infiltrating T lymphocytes (TILs).

RESULTS

Both PD1 and PDL1 expression was only observed in a small proportion of fibroblastic tumors, whereas TIM3 was expressed in almost all tumors. However, only the positive expression of PDL1 was related to tumors with high grade and staging. A considerable number of TILs, including CD4- and CD8A-positive T cells and a small group of FoxP3-positive T cells, was also observed in most tumors. The density of TIM3 was positively correlated with that of TILs. Furthermore, higher densities of TIM3, CD4, CD8A and FoxP3 were observed in PD1 and PDL1 double-positive fibroblastic tumors.

CONCLUSIONS

This study indicates that TILs with high expression of TIM3 may contribute to immunosuppression in the tumor microenvironment of fibroblastic tumors. Patients with fibroblastic tumors with high expression of PD1/PDL1 and TIM3 may therefore benefit from combination therapy with PD1/PDL1 and TIM3 inhibitors.

Research progress regarding programmed cell death 1/programmed cell death ligand 1 inhibitors combined with targeted therapy for treating hepatocellular carcinoma

In recent years, a number of targeted therapeutic agents have achieved success in phase III trials in patients with advanced hepatocellular carcinoma (HCC), including sorafenib, lenvatinib, and regorafenib. Immunotherapy is considered to be an effective treatment for advanced HCC. Immune checkpoint inhibitors targeting programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) are important antitumor immunotherapy agents that represent breakthroughs in the treatment of advanced HCC. However, treating advanced HCC is still a great challenge, and the need for new treatments remains urgent. This review briefly summarizes the research progress in the use of PD-1/PD-L1 inhibitors combined with targeted therapy for treating HCC.

Programmed cell death-ligand 1 (PD-L1)+ tumour cells and low-reacting programmed cell death 1 (PD1)+ tumour-infiltrating lymphocytes predict poor prognosis in Epstein-Barr virus+ diffuse large B-cell lymphoma

Epstein-Barr virus (EBV)⁺ diffuse large B-cell lymphoma (DLBCL) has specific tumour cell characteristics, and these patients have worse outcomes than EBV-negative DLBCL patients. We compared 38 EBV⁺ DLBCL patients with 43 methotrexate-associated EBV⁺ B-cell lymphoproliferative disorders (MTX⁺/EBV⁺ BLPDs) and 30 non-germinal centre (GC) subtype DLBCL. Lymphoma cells of the EBV⁺ DLBCL group were positive for BCL2 in 17 patients (44.7%), CMYC in 23 patients (60.5%), and p53 in 33 patients (86.8%), which was significantly higher than in the MTX⁺/EBV⁺ BLPD group (P < 0.05), and were positive for CD30 in 29 patients (76.3%), compared with two in non-GC subtype DLBCL (6.7%) (P < 0.0001). Significantly more EBV⁺ DLBCL patients (n = 16, 42.1%) had programmed cell death-ligand 1 (PD-L1)⁺ tumour cells than patients with non-GC subtype DLBCL (n = 5, 16.7%; P = 0.024), and PD-L1⁺ tumour cells were more common in advanced stages than in early stages (P = 0.048). Twenty-five EBV⁺ DLBCL patients (69.4%) had few reactive PD1⁺ tumour-infiltrating lymphocytes (TILs), compared with 12 patients with MTX⁺/EBV⁺ BLPDs (37.5%) (P = 0.008). In the EBV⁺ DLBCL group, CD30, BCL2, CMYC, and p53 expression was not related to patient prognosis. Poor outcomes were associated with PD-L1⁺ tumour cells (P = 0.001) and low-reacting PD1⁺ TILs (P = 0.02), while their combination conferred a worse outcome (P < 0.0001). Immune evasion by PD-L1⁺ tumour cells and exhaustion of PD1⁺ TILs may occur in EBV⁺ DLBCL patients, and PD-L1/PD1 interactions may influence tumour progression and poor prognosis.

Histone Deacetylase as a Valuable Predictive Biomarker and Therapeutic Target in Immunotherapy for Non-Small Cell Lung Cancer

Purpose

Histone deacetylase inhibitors (HDACis) are epigenetic regulators and used clinically for hematopoietic malignancies. Recently, HDACis have received attention as a factor that modulates the immune system. In this study, the role of histone deacetylase (HDAC) expression as a predictive marker in lung cancer patients who were treated with immune checkpoint inhibitors (ICIs) and the role of HDACi and ICI combination treatment in the mouse tumor model were analyzed.

Materials and Methods

The overall response rate (ORR) and progression-free survival (PFS) were analyzed by the expression of HDAC. In vitro assay, the mRNA and protein expression levels of cytokines and programmed death-ligand 1 (PD-L1) were analyzed after HDACi treatment. In vivo assay, TC-1 tumor-bearing mice were treated with HDACi and mouse programmed cell death 1 (PD-1) inhibitor.

Results

The HDAC6 low expression group showed high ORR and prolonged PFS. When the selective HDAC6 inhibitor was administered to the A549 cell line, the levels of interleukin-1β and interleukin-6 decreased and the expression of PD-L1 was reduced. Mice that received both the mouse PD-1 inhibitor and pan-HDACi had a smaller tumor size than that of the mice from the control group. Moreover, mice treated with the mouse PD-1 inhibitor and pan-HDACi generated greater numbers of E7-specific CD8⁺ T cells.

Conclusion

HDAC6 expression can predict the prognosis of non–small cell lung cancer patients who were treated with ICIs. Furthermore, co-treatment with HDACi and PD-1 inhibitor was shown to decrease the tumor growth rate and create a favorable tumor microenvironment for cytotoxic T lymphocytes in the TC-1 mouse model.

PD-1 Involvement in Peripheral Blood CD8+ T Lymphocyte Dysfunction in Patients with Acute-on-chronic Liver Failure

BACKGROUND AND AIMS

Programmed cell death-1 (PD-1) plays an important role in downregulating T lymphocytes but the mechanisms are still poorly understood. This study aimed to explore the role of PD-1 in CD8⁺ T lymphocyte dysfunction in hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF).

METHODS

Thirty patients with HBV-ACLF and 30 healthy controls (HCs) were recruited. The differences in the numbers and functions of CD8⁺ T lymphocytes, PD-1 and glucose transporter-1 (Glut1) expression from the peripheral blood of patients with HBV-ACLF and HCs were analyzed. In vitro, the CD8⁺ T lymphocytes from HCs were cultured (HC group) and the CD8⁺ T lymphocytes from ACLF patients were cultured with PD-L1-IgG (ACLF+PD-1 group) or IgG (ACLF group). The numbers and functions of CD8⁺ T lymphocytes, PD-1 expression, glycogen uptake capacity, and Glut1, hexokinase-2 (HK2), and pyruvate kinase (PKM2) expression were analyzed among the HC group, ACLF group and ACLF+ PD-1group.

RESULTS

The absolute numbers of CD8⁺ T lymphocytes in the peripheral blood from patients with HBV-ACLF were lower than in the HCs (p<0.001). The expression of PD-1 in peripheral blood CD8⁺ T lymphocytes was lower in HCs than in patients with HBV-ACLF (p=0.021). Compared with HCs, PD-1 expression was increased (p=0.021) and Glut1 expression was decreased (p=0.016) in CD8⁺ T lymphocytes from the HBV-ACLF group. In vitro, glycogen uptake and functions of ACLF CD8⁺ T lymphocytes were significantly lower than that in HCs (p=0.017; all p<0.001). When PD-1/PD-L1 was activated, the glycogen uptake rate and expression levels of Glut1, HK2, and PKM2 showed a decreasing trend (ACLF+PD-1 group compared to ACLF group , all p<0.05). The functions of CD8⁺ T lymphocytes in the ACLF+PD-1 group [using biomarkers of Ki67, CD69, IL-2, interferon-gamma, and tumor necrosis factor-alpha- were lower than in the ACLF group (all p<0.05).

CONCLUSIONS

CD8⁺ T lymphocyte dysfunction is observed in patients with HBV-ACLF. PD-1-induced T lymphocyte dysfunction might involve glycolysis inhibition.

Programmed cell death 1 (PD-1) receptor and programmed death ligand 1 (PD-L1) gene expression in primary breast cancer

PURPOSE

The interaction of the programmed cell death 1 (PD-1) receptor on tumor-infiltrating lymphocytes with programmed death ligand 1 (PD-L1) on tumor cells downregulates anti-tumor immunity. This study evaluated associations between PD-1 and PD-L1 expression in primary breast cancer, clinical characteristics, and patient outcomes.

METHODS

Microarray data from the Investigation of Serial Studies to predict your therapeutic response with imaging and molecular analysis (I-SPY 1) study (n = 149) was used to evaluate PD-1 and PD-L1 expression. Associations with clinical features and chemotherapy response were determined using Kruskal-Wallis and Wilcoxon rank sum tests, respectively. Recurrence-free survival (RFS) associations were determined with the Cox proportional hazard model. Associations of PD-1 and PD-L1 and selected genes associated with breast cancer, as well as a predictor of olaparib response (PARPi-7), were determined in I-SPY 1 and 2 other datasets: METABRIC (n = 1992) and TCGA (n = 817), using Pearson correlations.

RESULTS

In I-SPY 1, PD-1 expression was higher in triple-negative breast cancer (TNBC) and HER2 + breast cancer (p = 0.003), and grade 2/3 tumors (p = 0.043), and was associated with pathologic complete response (p = 0.006). PD-L1 expression in the lowest quintile was associated with worse RFS, even after subtype adjustment (HR 2.33, p = 0.01). PD-1 and PD-L1 gene expression correlated with the expression of immune-related genes and PARPi-7.

CONCLUSIONS

PD-1 expression is higher in breast cancers with aggressive features such as TNBC. Low PD-L1 expression may be an adverse prognostic factor. PD-1 and PD-L1 gene expression correlates with the expression of immune-related and DNA damage repair genes.

Programmed cell death 1 as prognostic marker and therapeutic target in upper gastrointestinal cancers

Gastrointestinal (GIs) cancers are among the most common causes of cancer related death, and hence the importance for the identification of novel prognostic/predictive biomarkers for detection of patients at an early stage, and for using these to identify novel targeted therapies to improve the efficacy of existing chemotherapeutic regimens. Programmed cell death 1 has been reported as a potential target in several malignancies, and targeting agents are being developed, some already approved by FDA, such as: pembrolizumab, Atezolizumab, Nivolumab. Pembrolizumab that have been approved for the treatment of metastatic non-small cell lung cancer. Here we provide an overview of the mechanism of action PD-1/PD-L1, prognostic value and current progress in clinical trials using PD-1/PD-L1 inhibitors, and the resistant mechanisms at underlie the inhibitory effect of these agents in the treatment of gastrointestinal cancers.

[Progress of PD-1/PD-L1 inhibitors in the treatment of small-cell lung cancer]

Small cell lung cancer (SCLC) is a neuroendocrine tumor, which accounts for about 15% of all lung cancers. SCLC is characterized by rapid growth and tendency to widespread metastasis at the initial stage. Although high response rates to first-line chemotherapy are observed, most patients relapse less than few months. In the past 5 years, some clinical trials found that the immune checkpoint inhibitors (ICIs) were effective in SCLC, especially programmed cell death 1/ligand 1 (PD-1/L1). Given this situation, the treatment patterns of SCLC have changed. This article briefly reviews the researches and studies of ICIs in the treatment of SCLC to provide reference to the clinicians.

Predicting hyperprogressive disease in patients with advanced hepatocellular carcinoma treated with anti-programmed cell death 1 therapy

BACKGROUND

Hyperprogressive disease (HPD) is a new progressive pattern in patients with advanced hepatocellular carcinoma (HCC) treated with programmed cell death 1 (PD-1) inhibitors. We aimed to investigate risk factors associated with HPD in advanced HCC patients undergoing anti-PD-1 therapy.

METHODS

A total of 69 patients treated with anti-PD-1 therapy between March 2017 and January 2020 were included. HPD was determined according to the time to treatment failure, tumour growth rate, and tumour growth rate ratio. Univariate and multivariate analyses were performed to identify clinical variables significantly associated with HPD. A risk model was constructed based on clinical variables with prognostic significance for HPD.

FINDINGS

Overall, 10 (14·49%) had HPD. Haemoglobin level, portal vein tumour thrombus, and Child-Pugh score were significantly associated with HPD. The risk model had an area under the curve of 0·931 (95% confidence interval, 0·844-1·000). Patients with HPD had a significantly shorter overall survival (OS) than that of the patients with non-HPD (p < 0·001). However, there was no significant difference in OS between PD (progressive disease) patients with and without HPD (p = 0·05).

INTERPRETATION

We identified three clinical variables as risk factors for HPD, providing an opportunity to aid the pre-treatment evaluation of the risk of HPD in patients treated with immunotherapy.

FUNDING

This study was funded by the National Natural Science Foundation of China (81571664, 81871323, and 81801665); National Natural Science Foundation of Guangdong Province (2018B030311024); Scientific Research General Project of Guangzhou Science Technology and Innovation Commission (201707010,328); and China Postdoctoral Science Foundation (2016M600145).

Clinical and pathological significance of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer

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PD-L1 expression in HGSOC requires further study with modern antibody reagents and platforms.

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The association of PD-L1 positive cases with CD8+ immune cells is more prominent.

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The checkpoint value in HGSOC is not yet clear, but there is an importance meaningful when the threshold is ≥5%.

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PD-L1 expression shows two immunohistochemical staining patterns, patchy/diffuse and patchy/focal.

We investigated programmed cell death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer (HGSOC) and its relationship to tumor infiltrating lymphocytes (TIL) and prognosis. Formalin fixed paraffin embedded (FFPE) samples of 94 HGSOC cases were included in the study. Immunohistochemical analysis (CD3, CD4, CD8, PD-1 and PD-L1) was performed. Samples were analyzed for expression of immune proteins in the peritumoral stromal and intratumoral areas, scored, and expression was correlated with overall survival, stage, and age. PD-L1 staining ratio with a score greater than 0 was found to have lower survival. There were two positive staining patterns, patchy/diffuse and patchy/focal patterns, in 24 (25.5%) cases. Considering the threshold value ≥5%, we demonstrated that the PD-L1 positive cancer cell membrane immunoreactivity rate and patchy/diffuse PD-L1 expression were 9.6% (n = 9). There was statistically significant relationship between high PD-1 scores and PD-L1 cases of ≥ 5%. A statistically significant difference was found between PD-L1 staining and survival in patients with a threshold ≥ 5%. However an appropriate rate for treatment was determined in 9.6% cases. There was a statistically significant correlation between PD-1 positive TIL score and intratumoral CD3, peritumoral stromal CD3, intratumoral CD4 and intratumoral CD8 positive cells. Survival was lower in cases with higher PD-L1 positive stromal TIL score.

Clinical utility of pretreatment Glasgow prognostic score in non-small-cell lung cancer patients treated with immune checkpoint inhibitors

OBJECTIVES

Immune checkpoint inhibitors (ICIs) have become one of the standard therapies in non-small-cell lung cancer (NSCLC). Although inflammatory indices, including Glasgow prognostic score (GPS), modified Glasgow prognostic score (mGPS), and C-reactive protein/albumin ratio (CAR) were reported to be reliable predictors for survival in cancer patients, their clinical utility in NSCLC patients treated with ICIs is unknown.

MATERIALS AND METHODS

Advanced or recurrent NSCLC patients (n = 304) treated with ICI monotherapy at the National Hospital Organization Kyushu Cancer Center and Kyushu University Hospital between January 2016 and December 2019 were analyzed. Information on patient demographics, GPS, mGPS, and CAR at diagnosis were collected. The time-dependent area under curves (AUCs) of receiver operating characteristic curves for the prediction of overall survival (OS) for each factor were compared.

RESULTS

Of the three indices, GPS was the most significantly correlated with the degree of disease control rate (DCR) (DCR of GPS of 0, 1, and 2: 63.6 %, 49.4 %, and 41.4 %, respectively). The time-dependent AUC values of GPS for the prediction of OS were superior to those of mGPS and CAR (time-dependent AUC values of GPS, mGPS, and CAR for the prediction of 1-year OS: 0.7005, 0.6736, and 0.6565, respectively). GPS was significantly correlated with performance status (PS) (P <  0.0001) and clinical stage (P =  0.0139). GPS in combination with PS effectively predicted survival at 1 year ranging from 83.5 % (GPS = 0, PS = 0) to 25.0 % (GPS = 2, PS = 2, 3). A multivariable analysis revealed that GPS was an independent predictor of PFS and OS (P =  0.0009 and P =  0.0100, respectively).

CONCLUSIONS

We report for the first time that GPS represents a simple and useful prognostic factor in NSCLC patients treated with ICIs and should be validated prospectively.

Anti-pituitary antibodies as a marker of autoimmunity in pituitary glands

Autoimmunity contributes to the pathogenesis of hypophysitis, a chronic inflammatory disease in the pituitary gland. Although primary hypophysitis is rare, the number of pituitary dysfunction cases induced by immune checkpoint inhibitors (ICIs) is increasing. While it is difficult to prove the involvement of autoimmunity in the pituitary glands, circulating anti-pituitary antibodies (APAs) can be measured by indirect immunofluorescence and used as a surrogate marker of pituitary autoimmunity. APAs are present in several pituitary diseases, including lymphocytic adenohypophysitis, lymphocytic infundibulo-neurohypophysitis (LINH), IgG4-related hypophysitis, and pituitary dysfunction induced by ICIs. Mass spectrometry analysis of antigens targeted by APAs clarified rabphilin-3A as an autoantigen in LINH. This demonstrates that APAs can be applied as a probe to identify novel autoantigens in other pituitary autoimmune diseases, including pituitary dysfunction induced by ICIs, which can aid in biomarker discovery.

A case with life-threatening secondary sclerosing cholangitis caused by nivolumab

Immune checkpoint inhibitor (ICI) therapy has potent anti-cancer effects but is associated with immune-related adverse events (irAEs). We present a case who developed secondary sclerosing cholangitis following treatment with nivolumab for non-small cell lung cancer who did not respond to immunosuppressive treatments and died of liver failure. A 75 year-old male with lung cancer who had been treated with nivolumab for non-small cell lung cancer developed Grade 3 liver injury with significant elevation of hepatobiliary enzymes. Magnetic resonance cholangiopancreatography (MRCP) revealed diffuse dilatation of the common bile duct and multifocal stenosis with prestenotic dilatation from the perihilar to intrahepatic bile duct, consistent with sclerosing cholangitis. Histological findings represented an infiltration of mainly CD8-positive T cells around the bile ducts in the liver. Despite treatments with ursodeoxycholic acid, prednisolone, and mycophenolate mofetil, the sclerosing cholangitis did not improve, and the patient died due to liver failure and aggravation of lung cancer. These findings suggest that immune checkpoint inhibitors may lead to resistance to immunosuppressive treatment as well as pose a risk of life-threatening sclerosing cholangitis.

[Present and Future of Efficacy Biomarkers in Immune Checkpoint Inhibitors of Small Cell Lung Cancer]

近年来，免疫治疗在小细胞肺癌领域取得了令人瞩目的突破，为患者带来生存获益。然而，现有的临床研究结果表明试验组通常在治疗开始3个月-6个月以后方可看出获益的趋势，因此如何筛选优势人群是免疫治疗研究的重点。目前已有的临床试验对生物标记物进行了不断地探索，但结果不尽一致。我们亟需有力可靠的疗效预测指标有效地筛选优势人群、扩大受益群体。故本文将对小细胞肺癌免疫治疗疗效预测指标的现状及未来的发展前进方向展开阐述。

Clinical burden of immune checkpoint inhibitor-induced pneumonitis

Immune checkpoint inhibitors (ICIs) have been a breakthrough in medical oncology. However, many patients experience a novel type of adverse drug reaction that has a unique clinical presentation, called immune-related adverse events (irAEs). A breakdown of self-tolerance and an exaggerated autoimmune reaction by the host are assumed to be the underlying mechanisms. Therefore, special attention to the optimal diagnosis and management is required. Among the various effects of irAE, pneumonitis has been recognized as an important manifestation because of its high morbidity and mortality. As the application of ICIs is expanding to a wider variety of tumor types, as well as its use with cytotoxic agents and radiation, clinicians are highly likely to encounter this complication. In this review, we will summarize the current understanding of the underlying mechanisms, incidence, risk factors, optimal diagnostic workup, and management of ICI-related pneumonitis (IRP). We will also review fundamental information on drug-induced lung toxicity in the oncology setting. In addition, research perspectives focused on better risk stratification and management to avoid serious complications in the future are presented.

PD-L1 expression in tongue squamous cell carcinoma

PURPOSE

Immune checkpoint proteins programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are important therapeutic targets for head and neck cancer. This large-scale case study aimed to analyze tongue squamous cell carcinomas (SCCs) and evaluate the correlation between PD-L1 expression and clinical prognosis. So far, this study is the largest case study on PD-L1 expression in tongue SCCs.

METHODS

This is a case-control study that analyzed 121 tongue SCCs. Paraffin-embedded sections and clinical data were obtained retrospectively and immunohistochemistry with PD-L1 was performed.

RESULTS

11.6% contained ≥ 50% of PD-L1-positive cells, 57.1% of these cases had a poor prognosis with nodal metastasis. Among cases of T1/2 primary lesions with nodal metastasis, cases of high PD-L1 expression had a significantly shorter disease-free survival than cases of no PD-L1 expression (p = 0.018). The hazard ratio for high PD-L1 expression was 3.21 (95 per cent CI, 1.26-8.72) compared with no PD-L1 expression after adjusting for other factors.

CONCLUSIONS

These data indicate that PD-L1 upregulation in tongue SCCs is associated with a more advanced stage and shorter disease-free survival. PD-1/PD-L1 inhibitors might hence constitute potential adjuvant therapy for tongue SCCs with PD-L1 upregulation.

Association of serine/threonine kinase 11 mutations and response to programmed cell death 1 inhibitors in metastatic gastric cancer

Programmed cell death 1 (PD-1) inhibitors have shown therapeutic efficacy in metastatic gastric cancer (mGC). However, no predictive biomarkers have been established in mGC. Inactivating mutations in serine/threonine kinase 11 (STK11) are associated with poor response to PD-1 inhibitors in KRAS-mutant lung adenocarcinoma. Therefore, we hypothesized that STK11 inactivating mutations would be associated with inferior clinical response to PD-1 inhibitors in mGC. We analyzed 59 mGC patients who had been treated with PD-1 inhibitors and whose tumors had been analyzed by targeted high-throughput sequencing. STK11 mutations were identified in 30 (50.8%) patients, and were all missense mutations. Three patients (5.1%) had STK11 gene amplification and mutation, simultaneously. Patients with STK11 mutations had prolonged overall survival (median: 19.0 vs 11.6 months, p = 0.15), and progression-free survival (4.2 vs 1.9 months, p = 0.06) when treated with PD-1 inhibitors, but these differences were not statistically significant. Patients with STK11 inactivating mutations without STK11 gene amplification had significantly prolonged progression-free survival compared to patients with wild type STK11 or STK11 gene amplification (4.8 vs 1.0 months, p = 0.04). However, in multivariate Cox regression analysis with high microsatellite instability (MSI-H), the number of tumor mutations, PD Ligand-1 (PD-L1)+, Epstein-Barr virus positivity (EBV)+, and type of PD-1 inhibitor used (pembrolizumab vs nivolumab), only MSI-H and PD-L1+ were significantly associated with longer progression-free survival. In mGC, the presence of STK11 mutation was not predictive of the response to PD-1 inhibitors. Instead, patients with MSI-H or PD-L1+ tumors displayed superior clinical responses to PD-1 inhibitors.

Rapid regression of microsatellite instability-high/programmed cell death ligand 1-negative recurrent endometrial carcinoma by immune checkpoint blockade with pembrolizumab: A case report and literature review

In a 53-year-old woman who had a surgical diagnosis of grade 3 endometrioid carcinoma (pT1aN0M0, FIGO 1A), adjuvant chemotherapy with paclitaxel and carboplatin was initiated. However, after the completion of fourth cycle, the patient refused to continue the treatment. At 12 months after surgery, local recurrence was noted near the left posterior portion of the vaginal stump. External radiotherapy to the pelvic cavity achieved marked reduction of the tumor. At 12 months after radiotherapy, regrowth of the tumor was noted. Although the tumor was negative for programmed cell death ligand 1, after the identification of a high level of microsatellite instability, treatment with pembrolizumab, an immune checkpoint inhibitor, was initiated. After 2 cycles of treatment, the recurrent tumor markedly regressed. Four months later, a complete metabolic response was confirmed by positron emission tomography, without any immune-related adverse events; at the time of writing, this has been maintained for 9 months.

Clinical Characteristics and Treatment of Immune-Related Adverse Events of Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) have been changing the paradigm of cancer treatment. However, immune-related adverse effects (irAEs) have also increased with the exponential increase in the use of ICIs. ICIs can break up the immunologic homeostasis and reduce T-cell tolerance. Therefore, inhibition of immune checkpoint can lead to the activation of autoreactive T-cells, resulting in various irAEs similar to autoimmune diseases. Gastrointestinal toxicity, endocrine toxicity, and dermatologic toxicity are common side effects. Neurotoxicity, cardiotoxicity, and pulmonary toxicity are relatively rare but can be fatal. ICI-related gastrointestinal toxicity, dermatologic toxicity, and hypophysitis are more common with anti- CTLA-4 agents. ICI-related pulmonary toxicity, thyroid dysfunction, and myasthenia gravis are more common with PD-1/PD-L1 inhibitors. Treatment with systemic steroids is the principal strategy against irAEs. The use of immune-modulatory agents should be considered in case of no response to the steroid therapy. Treatment under the supervision of multidisciplinary specialists is also essential, because the symptoms and treatments of irAEs could involve many organs. Thus, this review focuses on the mechanism, clinical presentation, incidence, and treatment of various irAEs.

Clinical Characteristics and Treatment of Immune-Related Adverse Events of Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs) have been changing the paradigm of cancer treatment. However, immune-related adverse effects (irAEs) have also increased with the exponential increase in the use of ICIs. ICIs can break up the immunologic homeostasis and reduce T-cell tolerance. Therefore, inhibition of immune checkpoint can lead to the activation of autoreactive T-cells, resulting in various irAEs similar to autoimmune diseases. Gastrointestinal toxicity, endocrine toxicity, and dermatologic toxicity are common side effects. Neurotoxicity, cardiotoxicity, and pulmonary toxicity are relatively rare but can be fatal. ICI-related gastrointestinal toxicity, dermatologic toxicity, and hypophysitis are more common with anti- CTLA-4 agents. ICI-related pulmonary toxicity, thyroid dysfunction, and myasthenia gravis are more common with PD-1/PD-L1 inhibitors. Treatment with systemic steroids is the principal strategy against irAEs. The use of immune-modulatory agents should be considered in case of no response to the steroid therapy. Treatment under the supervision of multidisciplinary specialists is also essential, because the symptoms and treatments of irAEs could involve many organs. Thus, this review focuses on the mechanism, clinical presentation, incidence, and treatment of various irAEs.

Isolated ACTH deficiency during single-agent pembrolizumab for squamous cell lung carcinoma: a case report

Background

The programmed cell death 1 (PD-1) inhibitor pembrolizumab is a promising agent for treatment of several different malignancies, but as with all immunotherapy there is a potential risk of immune-related adverse events. Adrenocorticotropic hormone (ACTH) deficiency and hypophysitis have been reported in patients treated with a different PD-1 inhibitor, nivolumab. However, clinical characteristics of these side effects associated with pembrolizumab have yet to be described in detail.

Case presentation

An 85-year-old Japanese woman was diagnosed with advanced squamous cell lung cancer. The patient was treated with 200 mg pembrolizumab every three weeks as first-line therapy. Routine examination including thyroid function, complete blood count, serum cortisol and sodium levels before each pembrolizumab infusion had shown no significant changes up to the eighth cycle. However, 8 days after the eighth cycle of single-agent pembrolizumab, she presented with rapidly worsening general fatigue and appetite loss over two days. Laboratory data revealed a low serum cortisol level (0.92 μg/dL) with inappropriately low ACTH (8.3 pg/mL), hyponatremia (122 mmol/L) and hypoglycemia (68 mg/dL). Standard-dose short ACTH testing showed an unsatisfactory cortisol response, indicating adrenal insufficiency. Pituitary magnetic resonance imaging showed diffuse substantial gadolinium enhancement, T2 hyperintensity, loss of pituitary bright spot, but no pituitary enlargement. Serum cortisol and ACTH levels were low throughout the day, and urinary free cortisol excretion fell below the lower normal limit. There was no ACTH and cortisol response in the corticotropin-releasing hormone test, despite significant responses of other anterior pituitary hormones to their corresponding challenge tests. Thus, isolated ACTH deficiency was diagnosed, and hypophysitis was suspected as the etiology. After administration of 15 mg/day hydrocortisone, the patient’s debilitation, hyponatremia, and hypoglycemia swiftly disappeared.

Conclusion

This is a case of isolated ACTH deficiency possibly due to hypophysitis in a patient with advanced lung cancer, in whom recent routine examinations had shown unremarkable results. We therefore conclude that isolated ACTH deficiency can suddenly arise during pembrolizumab monotherapy, albeit probably only rarely. Caution should be exercised to make sure that adrenal insufficiency is recognized immediately in order to achieve swift recovery by steroid replacement.

Malignant Melanoma in People Living with HIV/AIDS: Can We Know More, Can We Do Better?

Thanks to the advancement in understanding of molecular mechanisms driving immune surveillance, we have now approached a revolutionary era for the treatment of malignant melanoma (MM). Meanwhile, people living with HIV/AIDS (PLWHA) are aging and non-AIDS-related cancers have become a leading cause of death. Both HIV infection and melanoma share common immune-pathological pathways: immune checkpoints are being targeted for melanoma immunotherapy and investigated as a "shock and kill" strategy for latency reversion among HIV-positive individuals. Nevertheless, a substantial lack of information exists on epidemiology, clinical features, and management of MM in HIV, due to compartmentalized approaches and poor awareness about the problem. In this narrative review, we aimed at analyzing available data regarding MM in PLWHA to point out key knowledge gaps and future opportunities from an integrated dermatology, oncology, and infectious diseases standpoint. To date, a strong association between HIV infection and MM risk still needs to be effectively demonstrated; nevertheless, once this cancer has developed in HIV-positive people, it shows more aggressive course, worse prognosis, and seemingly peculiar clinical and histological features. Despite these challenges, a syndemic framework should lead us toward a tailored and multidisciplinary approach not to miss valuable opportunities from the worst situations including the enrolment of HIV-positive patients in the ongoing trials with immune checkpoint inhibitors.

Association Between Skin Reaction and Clinical Benefit in Patients Treated with Anti-Programmed Cell Death 1 Monotherapy for Advanced Non-Small Cell Lung Cancer

BACKGROUND

Anti-programmed cell death 1 antibody is a standard therapy for advanced non-small cell lung cancer (NSCLC). However, immune-related adverse events (irAEs), such as skin reactions, are frequently observed. Although skin reactions are associated with clinical efficacy in melanoma, this association in advanced NSCLC and predictors of irAEs remain unclear. Accordingly, this study identified potential correlations of skin reactions with clinical efficacy and clinical predictors of development of skin reactions.

SUBJECTS, MATERIALS, AND METHODS

We retrospectively surveyed patients with advanced NSCLC who received nivolumab or pembrolizumab monotherapy at Sendai Kousei Hospital (n = 155) during January 2016 to April 2018. Treatment efficacy was evaluated in patients with and without skin reactions, and associated predictive markers were determined. A 6-week landmark analysis was conducted to assess the clinical benefit of early skin reactions.

RESULTS

Skin reactions were observed in 51 patients with a median time to onset of 6.4 weeks. The overall response rate (ORR) was significantly higher in patients with skin reactions (57% vs. 19%, p < .001). Median progression-free survival (PFS) durations of 12.9 and 3.5 months and overall survival durations of not reached and 11.4 months were observed in patients with and without skin reactions, respectively. In the 6-week landmark analysis, the ORR was significantly higher in patients with skin reactions, and skin reactions were significantly associated with increased PFS. A multivariate analysis identified pre-existing rheumatoid factor (RF) as an independent predictor of skin reactions.

CONCLUSION

Skin reactions appeared beneficial in patients treated with nivolumab/pembrolizumab for advanced NSCLC and could be predicted by pre-existing RF. Further large-scale validations studies are warranted.

IMPLICATIONS FOR PRACTICE

This single-institutional medical record review that included 155 patients with advanced non-small cell lung cancer who were treated with nivolumab or pembrolizumab monotherapy revealed that overall response rate and progression-free survival were significantly better in patients with skin reactions. Pre-existing rheumatoid factor was an independent predictor of skin reactions.

Programmed cell death 1 gene polymorphism as a possible risk for systemic lupus erythematosus in Egyptian females

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with a suggested genetic basis. The newly identified human programmed cell death 1 gene could be associated with SLE susceptibility. We aimed to investigate the association between programmed cell death 1 polymorphism (PD1.3G/A (rs11568821) and PD1.5C/T (rs2227981)) with the risk of SLE in the Egyptian female population. This retrospective case-control study included 150 Egyptian females; 70 patients diagnosed to have SLE and 80 age-matched healthy controls. The two single nucleotide polymorphisms of the pdcd1 gene were genotyped by allelic discrimination through TaqMan real-time polymerase chain reaction. The PD1.3GG genotype and G allele as well as the PD1.5CC genotype were significantly more frequent in SLE patients (67.1%; p = 0.023, 82.1%; p = 0.0021, 62.9%; p = 0.0287 respectively). The GC haplotype was the most common haplotype among SLE patients (70.77%) with a reported significant linkage disequilibrium between the two studied polymorphisms (p = 0.0041). Although most of the studies showed significant association of SLE with the minor alleles, we reported a significant association between the dominant genotypes (PD1.3GG and PD1.5CC) as well as the major G allele with the risk of SLE among Egyptian females.

Unbalanced expression of membrane-bound and soluble inducible costimulator and programmed cell death 1 in patients with myasthenia gravis

This study aimed to investigate the possible functions and mechanisms of positive and negative costimulatory molecules in the pathological process of myasthenia gravis (MG). The expression levels of membrane-bound inducible costimulator (ICOS) and programmed cell death 1 (PD-1) in peripheral blood T cells, their corresponding ligands ICOSL and PDL-1 on B cells, and their soluble forms (sICOS, sPD-1, sICOSL, and sPDL-1) in plasma were detected in patients with untreated-stage MG (USMG) and remission-stage MG (RSMG). The results showed that the expression levels of membrane-bound ICOS and PD-1 in the peripheral blood T cells of the USMG group and their corresponding ligands ICOSL and PD-L1 on B cells were significantly increased compared to those in the RSMG group and healthy controls (HCs). The levels of sICOSL and sPD-1 were significantly upregulated in USMG patients compared to those in the RSMG and HC groups, while the levels of sICOS and sPD-L1 were not different. The expression of PD-L1 on CD19⁺ B cells was positively correlated with the concentrations of AchR Ab in the USMG group. The expression of ICOS and PD-1 in CD4⁺ T cells and the expression of ICOSL and PD-L1 on CD19⁺ B cells were positively correlated with the quantitative myasthenia gravis (QMG) scores in the USMG group. Also, in the USMG group, the plasma levels of sICOSL and sPD-1 were positively correlated with the QMG scores. In addition, the percentage of peripheral blood follicular helper T (Tfh) cells in the USMG group was positively correlated with ICOS and PD-1 expression on CD4⁺ T cells and ICOSL and PD-L1 expression on CD19⁺ B cells. There were positive correlations between sICOSL and sPD-1 levels and the percentage of peripheral blood Tfh cells and plasma interleukin-21 (IL-21) levels in the USMG group. The results suggest that the positive ICOS/ICOSL and negative PD-1/PD-L1 costimulatory molecule pairs participate in the pathological process of MG. Abnormal sICOSL and sPD-1 expression might interfere with the normal signal transduction of ICOS and PD-1 on Tfh cells, causing excessive activation of Tfh cells and promotion of disease progression. sICOSL and sPD-1 have potential value in monitoring MG disease states.

Natural Killer Cells and Thyroid Diseases

Abnormal production of thyroid hormone is one of the common endocrine disorders, and thyroid hormone production declines with age. The aging process also negatively affects the immune system. An interaction between endocrine system and the immune system has been proposed to be bidirectional. Emerging evidence suggests an interaction between a lymphocyte population, called natural killer (NK) cells and thyroid gland function. Here, we review the relationship between NK cells and thyroid function and disease.

Inflammatory myopathy associated with PD-1 inhibitors

OBJECTIVE

To characterize the inflammatory myopathy associated with programmed cell death 1 inhibitors (PD-1 myopathy).

METHODS

We studied 19 Japanese patients with PD-1 myopathy (13 men and 6 women, mean age 70 years), who were referred to Keio University. As control groups, we used 68 patients with anti-signal recognition particle antibodies, 51 patients with anti-aminoacyl transfer RNA synthetase antibodies and 460 healthy subjects.

RESULTS

In regard to muscle-disease severity, 10 patients showed a mild form of disease and 9 patients showed a severe form. Non-small cell lung cancer was the most common underlying cancer. PD-1 inhibitor consisted of 11 nivolumab and 8 pembrolizumab. PD-1 myopathy occurred 29 days on average after the first administration of PD-1 inhibitor. The initial manifestation of muscle weakness was ptosis in 10 patients, 15 patients had ptosis, 13 diplopia, 8 facial muscle weakness, 10 bulbar symptoms, 13 limb weakness, 14 neck weakness, 4 cardiac involvement, 6 respiratory involvement and 16 myalgia. Ocular, facial, cardiac and respiratory involvement and myalgia were more frequently observed than controls. Serum creatine kinase was increased to 5247 IU/L on average. Autoantibodies related to inflammatory myopathy were negative, while anti-striational antibodies were found in 13 (68%) patients. HLA-C*12:02 alleles were more frequently detected than healthy controls. Muscle pathology was characterized by multifocal necrotic myofibers with endomysial inflammation and expression of MHC class I. Immunosuppressive therapy with corticosteroids was generally effective for muscle weakness.

CONCLUSIONS

Based on our clinical, histological and immunological findings, PD-1 myopathy is a discrete subset of inflammatory myopathy.

The Cancer Immunogram as a Framework for Personalized Immunotherapy in Urothelial Cancer

CONTEXT

The abysmal outlook of urothelial cancer (UC) has changed with the introduction of immunotherapy. Still, many patients do not respond and distinctive biomarkers are currently lacking. The rise of this novel armamentarium of immunotherapy treatments, in combination with the complex biology of an immunological tumor response, warrants the development of a comprehensive framework that can provide an overview of important immunological processes at play in individual patients.

OBJECTIVE

To develop a comprehensive framework based on tumor- and host-specific parameters to understand immunotherapy response in UC. This framework can inform rational, biology-driven clinical trials and ultimately guide us toward individualized patient treatment.

EVIDENCE ACQUISITION

A literature review was conducted on UC immunotherapy, clinical trial data, and biomarkers of response to checkpoint inhibition.

EVIDENCE SYNTHESIS

Here, we propose a UC immunogram, based on currently available clinical and translational data. The UC immunogram describes several tumor- and host-specific parameters that are required for successful immunotherapy treatment. These seven parameters are tumor foreignness, immune cell infiltration, absence of inhibitory checkpoints, general performance and immune status, absence of soluble inhibitors, absence of inhibitory tumor metabolism, and tumor sensitivity to immune effectors.

CONCLUSIONS

Longitudinal integration of individual patient parameters may ultimately lead to personalized and dynamic immunotherapy, to adjust to the Darwinian forces that drive tumor evolution. Incorporating multiparameter biomarkers into quantitative predictive models will be a key challenge to integrate the immunogram into daily clinical practice.

PATIENT SUMMARY

Here, we propose the urothelial cancer immunogram, a novel way of describing important immunological characteristics of urothelial cancer patients and their tumors. Seven characteristics determine the chance of having an immunological tumor response. Using this immunogram, we aim to better understand why some patients respond to immunotherapy and some do not, to ultimately improve anticancer therapy.

PD-1 and PD-L1 Protein Expression Predict Survival in Completely Resected Lung Adenocarcinoma

BACKGROUND

We assessed the prognostic value of programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) in patients with completely resected lung adenocarcinoma.

PATIENTS AND METHODS

PD-1 and PD-L1 expression was determined using immunohistochemistry in formalin-fixed paraffin-embedded surgical specimens and correlated with the clinicopathologic features and survival of 161 patients with lung adenocarcinoma.

RESULTS

PD-1 expression on immune cells was observed in 71 of 159 evaluable tumor samples (45%) and was not significantly associated with the clinicopathologic features. Multivariate analyses identified PD-1 expression as an independent prognostic factor for recurrence (adjusted hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.36-0.95; P = .03) and death (adjusted HR, 0.48; 95% CI, 0.27-0.86; P = 0.01). PD-L1 expression on tumor cells was seen in 59 of 161 cases (37%) and correlated with KRAS mutation status (P = .02) and type of surgery (P = .01). PD-L1 expression was not associated with recurrence-free survival in the patients (adjusted HR, 0.90; 95% CI, 0.55-1.48; P = .68) but correlated with longer overall survival (adjusted HR, 0.54; 95% CI, 0.30-0.97; P = .04).

CONCLUSION

PD-1 and PD-L1 expression was associated with favorable overall survival in patients with completely resected adenocarcinoma of the lung.

Advances in immuno-oncology biomarkers for gastroesophageal cancer: Programmed death ligand 1, microsatellite instability, and beyond

Blockade of the programmed death ligand 1 (PD-L1) and programmed cell death 1 (PD-1) receptor axis represents an effective form of cancer immunotherapy. Preclinical evidence initially suggested that gastric and gastroesophageal junction (GEJ) cancers are potentially immunotherapy-sensitive tumors. Early phase clinical trials have demonstrated promising antitumor activity with PD-1/PD-L1 blockade in advanced or metastatic gastric/GEJ cancer. Microsatellite instability (MSI) and PD-L1 expression have been shown to predict higher response to PD-1 inhibitors as highlighted by the recent approvals of pembrolizumab in treatment-refractory solid tumors with MSI status and the third-line or greater treatment of PD-L1 positive advanced gastric/GEJ cancers. However, predictive and prognostic biomarkers remain an ongoing need. In this review, we detail the preclinical evidence and early tissue biomarker analyses illustrating potential predictive biomarkers to PD-1/PD-L1 blockade in gastric/GEJ cancer. We also review the clinical development of PD-1/PD-L1 inhibitors in gastric/GEJ cancer and highlight several areas in need of future investigation in order to optimize the efficacy of PD-1/PD-L1 blockade in gastric/GEJ cancer.

[Association of PD-1, TIM-3 and TREM-1 single nucleotide polymorphisms with pulmonary tuberculosis susceptibility]

Objective: To investigate the association of programmed cell death 1(PD-1), T cell immunoglobulin mucin 3 (TIM-3) and triggering receptor expressed on myeloid cells-1 (TREM-1) genes polymorphisms with pulmonary tuberculosis susceptibility. Methods: In this case-control study, peripheral venous blood of 100 pulmonary tuberculosis patients (pulmonary tuberculosis group) in the Jintan People's Hospital of Changzhou and of community physical examination volunteers (health control group) was collected from Mar 2015 to Sep 2016. A total of 66 single nucleotide polymorphisms (SNP) in PD-1, TIM-3 and TREM1 sequences were selected and SNP genotype and allele frequency were analyzed using the next-generation sequencing technology. Association of these SNP with pulmonary tuberculosis susceptibility was investigated using linkage disequilibrium (LD) analysis and genetic models. Results: Among these 66 SNP, 24 SNP with Hardy-Weinberg equilibrium P (HWE-P) value <0.001 or minimum allele frequency (MAF) <0.05 were kicked out. The remaining 42 SNP were analyzed with LD analysis and genetic models. There was no significant difference in genotype frequencies between pulmonary tuberculosis group and health control group (all P>0.05). Five SNP (rs41435650, rs28539662, rs13023138, rs75565781, rs36084323) in PD-1 were identified in a significant haplotype (TACGC) between pulmonary tuberculosis group and health control group (P=0.014). Among these haplotypes, strong LD was observed between rs28539662 and rs75565781 (r(2)=0.871), as well as rs36084323 (r(2)=0.864). Rs75565781 showed highest correlation with rs36084323 (r(2)=0.966). Conclusion: These SNP in PD-1, TIM-3 and TREM-1 genes are not associated with the susceptibility of pulmonary tuberculosis.

Bullous Pemphigoid as an Adverse Reaction to Pembrolizumab: Two Case Reports

Checkpoint inhibitors are novel and promising treatment options for different types of cancer. Programmed cell death 1 (PD-1) inhibitors, such as pembrolizumab, have been shown to significantly raise the survival rates of disseminated malignant melanoma (MM). Autoimmune adverse reactions are very common in checkpoint inhibitors. We present 2 cases of bullous pemphigoid, as adverse reactions to pembrolizumab-treated MM.

Docetaxel Down-Regulates PD-1 Expression via STAT3 in T Lymphocytes

BACKGROUND

Lung tumor is a major cause of cancer incidence and patient death. Chemotherapy is the primary therapy used to treat lung cancer. In addition to direct cytotoxic effect on tumor cells, chemotherapeutic drugs activate immune responses to exert antitumor function. Here, the effects of docetaxel on the inhibitory molecules, programmed cell death 1 (PD-1), cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), and T-cell immunoglobulin and mucin domain 3 (TIM-3) in T lymphocytes were explored in patients with lung adenocarcinoma.

PATIENTS AND METHODS

Peripheral blood mononuclear cells were isolated from lung adenocarcinoma patients receiving cisplatin-docetaxel chemotherapy. By flow cytometry and PCR, the expressions of CTLA-4, PD-1 and TIM-3 in T cell subsets were analyzed. Health subjects were used as control group.

RESULTS

During chemotherapy, suppressive markers were down-regulated in peripheral CD4⁺ and CD8⁺ T cells from patients with partial remission or stable disease. Additionally, interferon-γ production was also augmented during this period. In vitro assay showed that docetaxel reduced the expression of PD-1 on T-cell subsets without altering cell death. Further tests in Jurkat T cells demonstrated that docetaxel activated signal transduction and activator of transcription 3 (STAT3) signaling to suppress PD-1 expression, whereas STAT3 inhibition reversed the down-regulation of PD-1.

CONCLUSION

Our data support the hypothesis that chemotherapeutic drugs are not only purely cytotoxic but are also immune modulators.

Expression of programmed cell death 1/programmed cell death ligand 1 in the tumor microenvironments of primary gastrointestinal diffuse large B cell lymphomas

BACKGROUND

Gastrointestinal diffuse large B cell lymphoma (GI DLBCL) is the most common gastrointestinal lymphoma. However, there has not been a comprehensive investigation into the expression patterns of programmed cell death 1 (PD-1) and programmed cell death ligand 1(PD-L1) in GI DLBCL tissues.

METHODS

PD-1 protein expression in tumor-infiltrating lymphocytes (TILs) was evaluated by immunohistochemical staining, and expression of PD-L1 was evaluated by using PD-L1/PAX5 immunohistochemical double staining in 92 GI DLBCL specimens.

RESULTS

The prevalence of positive PD-L1 expression (PD-L1 + ) in GI DLBCL cells and positive PD-L1 expression in non-cancer cells of the GI DLBCL microenvironment (microenvironmental PD-L1, mPD-L1) were 11.96% (11 of 92) and 41.98% (34 of 81), respectively. PD-L1 expression in GI DLBCL was significantly associated with involvement of extranodal sites ≥ 2 (P = 0.034) and mPD-L1 expression was significantly associated with ECOG performance status (score ≥ 2) (P = 0.041). PD-L1 expression and mPD-L1 expression had no prognostic significance (P > 0.05) on disease outcome. PD-1+ TILs were significantly lower in patients with extranodal site involvement (P = 0.011) and the quantity of PD-1 + TILs correlated positively with the level of PDL1 expression in non malignant microenvironment cells (P = 0.001). Patients with high levels of PD-1+ TILs had better prognosis (P = 0.0005).

CONCLUSIONS

The expression patterns of PD-L1 in patients with GI DLBCL are different from patients with common DLBCL. Immunotherapies that target the PD-1/PD-L1 pathway may have therapeutic potential in GI DLBCL.

Efficacy and safety of nivolumab in previously treated patients with non-small cell lung cancer: A multicenter retrospective cohort study

INTRODUCTION

Nivolumab has been shown to be effective and safe in previously treated patients with advanced non-small cell lung cancer (NSCLC). However, little is known regarding its performance in real-world (i.e., non-trial) settings. Furthermore, nivolumab efficacy is unknown in patients who are ineligible for clinical trials or who are categorized into small subgroups in such trials.

METHODS

We conducted a 15-center, observational, retrospective cohort study of patients with advanced NSCLC who received nivolumab monotherapy between January and December 2016.

RESULTS

Of 613 patients included in our study, 141 had poor performance status (PS) and 106 were EGFR mutation - or ALK rearrangement-positive. The response and disease control rates were 20% and 44%, respectively; the estimated 1-year progression-free survival (PFS) was 18%. Multivariate analysis identified never smoking, poor PS, and EGFR mutation/ALK rearrangement as independent negative predictors of PFS. The most frequently reported grade ≥3 adverse event was pneumonitis (5% of patients). Severe pneumonitis (grade ≥3) occurred significantly earlier than mild pneumonitis (1.6 vs. 2.3 months, P = 0.031). Patients with pneumonitis achieved higher response rates and longer PFS than those without (37% vs. 18%, and 5.8 vs. 2.1 months, respectively; P = 0.002).

CONCLUSIONS

Smoking status, PS, and EGFR mutation/ALK rearrangement were independent predictors of PFS. Our study elucidated nivolumab's efficacy in previously underreported patient populations; i.e., those with poor PS and/or with driver oncogenes. We also found that pneumonitis is not infrequent, and carries key implications for outcomes. These data should be useful for improving the clinical courses of nivolumab-treated patients with NSCLC.

Decreased T helper 17 cells in tuberculosis is associated with increased percentages of programmed death ligand 1, T helper 2 and regulatory T cells

Background

Tuberculosis (TB) is one of the most common infectious diseases worldwide. During active tuberculosis, T helper (Th) 17 cells are decreased, however the association with inhibitory immune regulation is unclear.

Methods

We enrolled 27 patients with TB and 20 age- and sex-matched controls and studies their lymphocyte status. Peripheral blood lymphocytes were isolated and programmed death-1 (PD-1) and programmed death ligand 1 (PD-L1) were measured on Th17 cells by using flow cytometry after the cells were stimulated with phorbol 12-myristate 13-acetate and ionomycin for 6 h. In addition, Th2 and regulatory T cells were measured and analyzed.

Results

The TB group had lower levels of Th17 cells but higher levels of Th2 and Treg cells than the controls. In Th17 cells, the percentage of PD-L1 was higher in the TB group than that in the controls. In Th2 and Treg cells, the percentage of cytotoxic T-lymphocyte associated protein 4 (CTLA-4) was lower in the TB group and PD-1 was higher in Treg cells in the TB group. In the patients with extra-pulmonary TB, levels of Th1, Th2 and T17 cells were lower than those with pulmonary TB. The percentage of PD-1 on Th1 lymphocytes positively correlated with radiographic score.

Conclusions

Lower level of Th17 in TB patients may be associated with increased percentage of PD-L1 and increasing levels of Th2 and Treg cells which influenced by CTLA-4.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-017-0580-3) contains supplementary material, which is available to authorized users.