Programmed Cell Death 1 Antibody Research Articles

SHISA3 Reprograms Tumor-Associated Macrophages Toward an Antitumoral Phenotype and Enhances Cancer Immunotherapy.

The main challenge for immune checkpoint blockade (ICB) therapy lies in immunosuppressive tumor microenvironment (TME). Repolarizing M2-like tumor-associated macrophages (TAMs) into inflammatory M1 phenotype is a promising strategy for cancer immunotherapy. Here, this study shows that the tumor suppressive protein SHISA3 regulates the antitumor functions of TAMs. Local delivery of mRNA encoding Shisa3 enables cancer immunotherapy by reprogramming TAMs toward an antitumoral phenotype, thus enhancing the efficacy of programmed cell death 1 (PD-1) antibody. Enforced expression of Shisa3 in TAMs increases their phagocytosis and antigen presentation abilities and promotes CD8+ T cell-mediated antitumor immunity. The expression of SHISA3 is induced by damage/pathogen-associated molecular patterns (DAMPs/PAMPs) in macrophages via nuclear factor-κB (NF-κB) transcription factors. Reciprocally, SHISA3 forms a complex with heat shock protein family A member 8 (HSPA8) to activate NF-κB signaling thus maintaining M1 polarization of macrophages. Knockout Shisa3 largely abolishes the antitumor efficacy of combination immunotherapy with Toll-like receptor 4 (TLR4) agonist monophosphoryl lipid A (MPLA) and PD-1 antibody. It further found that higher expression of SHISA3 in antitumoral TAMs is associated with better overall survival in lung cancer patients. Taken together, the findings describe the role of SHISA3 in reprogramming TAMs that ameliorate cancer immunotherapy.

HSPA4 upregulation induces immune evasion via ALKBH5/CD58 axis in gastric cancer

IntroductionGastric cancer (GC) is one of the leading causes of cancer-related death worldwide. Recently, targeted therapies including PD1 (programmed cell death 1) antibodies have been used in advanced GC patients. However, identifying new biomarker for immunotherapy is still urgently needed. The objective of this study is to unveil the immune evasion mechanism of GC cells and identify new biomarkers for immune checkpoint blockade therapy in patients with GC.MethodsCoimmunoprecipitation and meRIP were performed to investigate the mechanism of immune evasion of GC cells. Cocuture system was established to evaluate the cytotoxicity of cocultured CD8+ T cells. The clinical significance of HSPA4 upregulation was analyzed by multiplex fluorescent immunohistochemistry staining in GC tumor tissues.ResultsHistone acetylation causes HSPA4 upregulation in GC tumor tissues. HSPA4 upregulation increases the protein stability of m6A demethylase ALKBH5. ALKBH5 decreases CD58 in GC cells through m6A methylation regulation. The cytotoxicity of CD8+ T cells are impaired and PD1/PDL1 axis is activated when CD8+ T cells are cocultured with HSPA4 overexpressed GC cells. HSPA4 upregulation is associated with worse 5-year overall survival of GC patients receiving only surgery. It is an independent prognosis factor for worse survival of GC patients. In GC patients receiving the combined chemotherapy with anti-PD1 immunotherapy, HSPA4 upregulation is observed in responders compared with non-responders.ConclusionHSPA4 upregulation causes the decrease of CD58 in GC cells via HSPA4/ALKBH5/CD58 axis, followed by PD1/PDL1 activation and impairment of CD8+ T cell’s cytotoxicity, finally induces immune evasion of GC cells. HSPA4 upregulation is associated with worse overall survival of GC patients with only surgery. Meanwhile, HSPA4 upregulation predicts for better response in GC patients receiving the combined immunotherapy.

Circular RNA circNCOA3 promotes tumor progression and anti-PD-1 resistance in colorectal cancer.

Aim: Circular RNAs (circRNAs) have been found to be involved in tumor progression, but their role in colorectal cancer (CRC) immune escape remains to be elucidated. Methods: circRNAs differentially expressed in responsive and resistant CRC tissues to programmed cell death 1 (PD-1) antibody therapy were identified by microarray analysis. The clinical and pathological significance of circNCOA3 was validated in a separate cohort of CRC samples. The function of circNCOA3 was explored experimentally. RNA immunoprecipitation and luciferase activity assays were conducted to identify downstream targets of circNCOA3. Results: The circNCOA3 was markedly overexpressed in CRC samples resistant to PD-1 blockade. circNCOA3 expression was significantly correlated with adverse tumor phenotypes and poor outcomes in CRC patients. Knockdown of circNCOA3 expression markedly suppressed the proliferative and invasive capability of CRC cells. Moreover, knockdown of circNCOA3 increased the proportion of CD8+ T cells while decreasing the proportion of myeloid-derived suppressor cells (MDSCs). Knockdown of circNCOA3 inhibited tumor growth and increased the sensitivity to PD-1 antibody treatment in mouse tumor models. Further studies revealed that circNCOA3 acted as a competing endogenous RNA (ceRNA) for miR-203a-3p.1 to influence the level of CXCL1. Conclusion: Our findings indicate that circNCOA3 might be useful as a potential biomarker to predict the efficacy and prognosis of CRC patients treated with anti-PD-1 therapy.

Intratumor tertiary lymphatic structure evaluation predicts the prognosis and immunotherapy response of patients with colorectal cancer.

Immune checkpoint therapy, involving the programmed cell death 1 (PD-1) monoclonal antibody, has revolutionized the treatment of cancer. Tertiary lymphatic structure (TLS) serves as an immune indicator to predict the efficacy of PD-1 antibody therapy. However, there is no clear result whether the distribution, quantity, and maturity of TLS can be effective indicators for predicting the clinical efficacy of anti-PD1 immunotherapy in patients with colorectal cancer (CRC). Fifty-seven patients who underwent surgical resection and thirty-nine patients who received anti-PD-1 immunotherapy were enrolled in this retrospective study. Immunohistochemical staining and multiple fluorescence immunohistochemistry were used to evaluate the mismatch repair (MMR) subtypes and TLS distribution, quantity, and maturity, respectively. A comprehensive patient score system was built based on TLS quantity and maturity. We found that the proportion of patients with score >1 was much higher in the deficient mismatch repair(dMMR) group than in the proficient mismatch repair(pMMR) group, and this difference was mainly due to intratumoral TLS. Patient score, based on the TLS evaluation of whole tumor, peritumor, or intratumor, was used to evaluate the efficacy of anti-PD1 immunotherapy. Based only on the intratumor TLS evaluation, the proportion of patients with a score >1 was higher in the response (PR + CR) group than in the non-response (PD) group. Multivariate analysis revealed that patient scores were positively correlated with the clinical efficacy of immunotherapy. Further analysis of immune-related progression-free survival was performed in patients with CRC who received anti-PD-1 immunotherapy. Patients with score >1 based on the intratumor TLS evaluation had significantly better survival. These results suggest that the patient score based on intratumor TLS evaluation may be a good immune predictive indicator for PD-1 antibody therapy in patients with CRC.

Immunotherapy in Gastric Cancer: A Review

Globally, gastric cancer (GC) ranks fourth in terms of cancer-related mortality. Patients diagnosed with advanced gastric cancer (AGC) frequently have a median survival around 12-15 months, depending to the therapy. Immunotherapy is becoming an essential therapeutic strategy in medical oncology, and it is projected to make major advances to the way gastric cancer cure. The phase III ATTRACTION-2 showed that nivolumab, a monoclonal antibody targeting programmed cell death 1 (PD-1), substantially increased overall survival (OS) in patients with advanced gastric cancer (AGC) when given as a third- or later-line treatment, as compared to a placebo. Furthermore, nivolumab in combination with 5-fluorouracil and platinum as a first-line treatment increased OS in patients with human epidermal growth factor receptor-2 (HER2)-negative AGC in the international phase III CheckMate-649 investigation. Pembrolizumab, an additional anti PD-1 antibody, when used with trastuzumab and cytotoxic chemotherapy as first line treatment, demonstrated a substantial enhancement in the overall response rate among patients diagnosed with HER2-positive AGC. Hence, immune checkpoint inhibitors (ICIs) are crucial in the present management of GC. Current research is actively investigating alternative treatment following ICI combination therapy, including ICI rechallenge or combination therapy with drugs that have distinct mechanisms of action. Several clinical trials are presently being done to employ immunotherapy as a treatment option in the perioperative and postoperative settings for patients with early gastric cancer, based on the success of immunotherapy in treating advanced gastric cancer (AGC). This article gives an overview of the recent breakthroughs in immunotherapy.

Predictive Value of Peripheral Blood Biomarkers in the Treatment of Lung Cancer Patients with Anti PD-1 Immunotherapy

The application of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) antibodies has greatly improved the clinical outcomes of lung cancer patients. Here, we retrospectively analyzed the efficacy of PD-1 antibody therapy in locally advanced non-surgical or metastatic lung cancer patients, and preliminarily explored the correlation between peripheral blood biomarkers and clinical responses. We conducted a single center study that included 61 IIIA-IV lung cancer patients who received PD-1 antibody treatment from March 2020 to December 2021, and collected the medical record data on PD-1 antibody first-line or second-line treatment. The levels of multiple Th1 and Th2 cytokines in the patient's peripheral blood serum, as well as the phenotype of peripheral blood T cells, were detected and analyzed. All the patients completed at least 2 cycles of PD-1 monoclonal antibody treatment. Among them, 42 patients (68.9%) achieved partial response (PR); 7 patients (11.5%) had stable disease (SD); and 12 patients (19.7%) had progressive disease (PD). The levels of peripheral blood interferon gamma (IFN-γ) (P=0.023), tumor necrosis factor α (TNF-α) (P=0.007) and interleukin 5 (IL-5) (P=0.002) before treatment were higher in patients of the disease control rate (DCR) (PR+SD) group than in the PD group. In addition, the decrease in absolute peripheral blood lymphocyte count after PD-1 antibody treatment was associated with disease progression (P=0.023). Moreover, the levels of IL-5 (P=0.0027) and IL-10 (P=0.0208) in the blood serum after immunotherapy were significantly increased compared to baseline. Peripheral blood serum IFN-γ, TNF-α and IL-5 in lung cancer patients have certain roles in predicting the clinical efficacy of anti-PD-1 therapy. The decrease in absolute peripheral blood lymphocyte count in lung cancer patients is related to disease progression, but large-scale prospective studies are needed to further elucidate the value of these biomarkers.

Brentuximab Vedotin Combined with Chemotherapy in the Treatment of Pediatric Patients with R/R Hodgkin Lymphoma: Results of a Real World Setting Study

INTRODUCTION: Hodgkin Lymphoma (HL) is a familiar malignant lymphoma of the lymphatic system that accounts for 10% of all lymphoma diagnoses and 5% of lymphoma-related deaths. According to statistics, the incidence of HL in children and adolescents (0-19 years old) in China is about 1.78/million, and an average of 569 new cases are estimated annually from 2019 to 2021 . Brentuximab vedotin (BV) is an antibody-drug conjugates (ADC) that selectively delivers monomethyl auristatin E, an antimicrotubule agent, into CD30-expressing cells. Most of the data on the efficacy and safety of BV came from prospective and retrospective studies in adults or foreign children, and there are insufficient data in Chinese children. The purpose of this study is to explore the efficacy and safety of BV Combined with chemotherapy in Chinese pediatric patients with refractory and/or relapsed Hodgkin's lymphoma. METHODS: Retrospective analysis of clinical data of 9 children with refractory and/or relapsed Hodgkin's lymphoma from October 2021 to May 2023 at Beijing Children's Hospital, Capital Medical University. Patients were classified according to: clinical stage(Ann Arbor stage), huge tumor, huge tumor in the mediastinum, symptoms of B, and whether multiple lymph nodes were involved. Among them, the low-risk group was IA, ⅡA without giant tumor. The middle risk group was IB and ⅢA without huge tumor. High-risk groups were patients with stage ⅡB, ⅢB, Ⅳ or (each stage) with large tumors, or children with > 4 lymph node regions. All patients received BV in combination with chemotherapy for at least 2 cycles, and patients were assessed for remission response according to the Revised Response Criteria for Malignant Lymphoma at the end of every 2 cycles and followed up until July 20, 2023. RESULTS: Totally 32 cycles of chemotherapy were recorded, including 36 doses of BV administration(Table 1). The overall response rate of the children after 2 cycles of treatment was 100%, and the complete response rate was 88.89%. After remission, 2 cases (P1, P2) were treated with BV single drug 1.8mg/kg, Q3W for 6 months, and 3 cases (P3, P4, P7) were treated with radiotherapy. Two patients (P5, P6) received sequential chemotherapy, and two patients (P8, P9) were followed by programmed cell death 1(PD-1) antibody maintenance treatment for 6 months. After receiving PD-1 antibody for 6 months, 1 patient (P9) was transferred to BV monotherapy for maintenance, with 18 times planned. 2 cases (P1, P2) were then treated with autologous stem cell transplantation. None of the children developed disease progression during treatment. All patients successfully completed all planned dosage of BV, and serious adverse events were dominated by grade 3 or higher hematocrit, none of which interfered with normal treatment. Interpretation. BV had demonstrated the better efficacy and tolerable safety profile in the treatment of refractory and/or relapsed Hodgkin's lymphoma in children. CONCLUSIONS: BV has been approved by National Medical Products Administration in China since 2020, the clinical cases are mostly from adult lymphoma patients, and children data of in China is rare. In this study, we retrospectively reviewed and analyzed the data of BV combined chemotherapy in the treatment of refractory and relapsed Hodgkin lymphoma from single center, and found that the treatment response was rapid, continuousand safe. However, this study is a single-center retrospective study with a small sample size So We are conducting a prospective study of BV in first-line Hodgkin lymphoma children patients in China and aiming to generate more data for this specific population.

Short-course radiotherapy combined with chemotherapy and PD-1 inhibitor in low-lying early rectal cancer: study protocol for a single-arm, multicentre, prospective, phase II trial (TORCH-E)

IntroductionCurrent standard treatment for patients with early rectal cancer is radical surgical resection. Although radical surgery provides effective local tumour control, it also increases the mortality risk and considerable adverse...

Endostatin in combination with PD-1 antibody plus chemotherapy as first-line regimen for EGFR/ALK-negative, advanced or metastatic non-small cell lung cancer: A real-world study.

e20564 Background: In recent years, treatment for advanced or metastatic NSCLC has been significantly improved with the emergence of a combination strategy of immunotherapy with antiangiogenic drugs plus chemotherapy. Although endostatin (an antiangiogenic agent) combined with chemotherapy has been approved by the China Food and Drug Administration in treatment-naïve and re-treatment NSCLC patients, the clinical evidence supporting its combination with programmed cell death-1 (PD-1) antibody for advanced or metastatic NSCLC is still insufficient. Therefore, we aimed to evaluate the effectiveness and safety of endostatin combined with PD-1 antibody plus chemotherapy as the first-line treatment for locally advanced or distant metastatic NSCLC with EGFR/ALK-negative. Methods: This was a retrospective, singer-center, real-world study conducted between June 2018 and December 2021. The primary endpoint was progression-free survival (PFS); the secondary endpoints were objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety. Results: Overall, 68 patients were included. The median PFS and OS were 22.0 months (95% confidence interval [CI]: 16.6-27.4 months) and 31.0 months (95% CI: 23.4 months-not reached [NR]), respectively, with a median follow-up of 21.4 months (range, 8.3-44.4 months). At the data cutoff, 33 patients (48.5%) remained progression-free and 24 patients (35.3%) had died. Short-term clinical efficacy was assessed after 2 consecutive treatment cycles, with an ORR of 72.06% (complete response [CR], n = 3; partial response [PR], n = 46) and a DCR of 95.59% (CR, n = 3; PR, n = 46; stable disease, n = 16). Further subgroup analysis determined that a significantly better ORR (89.2% vs. 51.6%), median PFS (23.4 vs. 13.2 months), and median OS (NR vs. 18.0 months) for patients with stage Ⅲ B/Ⅲ C vs. stage Ⅳ NSCLC (all p ≤ 0.001). Besides, the median PFS (8.0 months vs. 22.5 months, p = 0.004) and OS (13.0 vs. 31.0 months, p = 0.027) of patients with brain metastasis were significantly shorter than those without brain metastasis. The ORR in patients who had a PD-L1 tumor proportion score (TPS) of < 1%, 1%-49%, ≥ 50%, and unknown were 50%, 50%, 75.0%, and 86.1%, respectively ( p = 0.025). All patients (100%) experienced treatment-related adverse events (AEs). The majority of AEs were grade 1 or 2 (57/68, 83.82%). Conclusions: In the real-world scenario, endostatin combination with PD-1 antibody plus chemotherapy obtained encouraging efficacy and favorable safety in advanced or metastatic NSCLC. The combination strategy in this study furnished beneficial evidence for the treatment of advanced or metastatic NSCLC and is essential for determining the best treatment option.

Surgically Derived Cancer Cell Membrane-Coated R837-Loaded Poly(2-Oxazoline) Nanoparticles for Prostate Cancer Immunotherapy.

Cancer cell membranes (CCMs) are widely used as sources of tumor-associated antigens (TAAs) for the development of cancer vaccines. To improve the CCM-associated cancer vaccine efficiency, personalized cancer vaccines and effective delivery systems are required. In this study, we employed surgically harvested cancer tissues to prepare personalized CCMs for use as TAAs. Thioglycolic-acid-grafted poly(2-methyl-2-oxazoline)-block-poly(2-butyl-2-oxazoline-co-2-butenyl-2-oxazoline) (PMBEOx-COOH) was synthesized to load imiquimod (R837) efficiently. The personalized CCMs were then coated onto R837-loaded PMBEOx-COOH nanoparticles (POxTA NPs/R837) to obtain surgically derived CCM-coated POxTA NPs (SCNPs/R837). SCNPs/R837 efficiently travelled to the draining lymph nodes and were taken up and presented by plasmacytoid dendritic cells to elicit enhanced antitumor immune responses. When combined with programmed cell death-1 antibodies, SCNPs/R837 exhibited high efficiency corresponding to antitumor progression. Therefore, SCNP/R837 might represent a promising personalized cancer vaccine with significant potential for cancer immunotherapy.

Disrupted BRCA1-PALB2 interaction induces tumor immunosuppression and T-lymphocyte infiltration in HCC through cGAS-STING pathway.

BRCA1 (BRCA1 DNA repair associated) and PALB2 (partner and localizer of BRCA2) interact with each other to promote homologous recombination and DNA double-strand breaks repair. The disruption of this interaction has been reported to play a role in tumorigenesis. However, its precise function in HCC remains poorly understood. We demonstrated that mice with disrupted BRCA1-PALB2 interaction were more susceptible to HCC than wild-type mice. HCC tumors arising from these mice showed plenty of T-lymphocyte infiltration and a better response to programmed cell death 1 (PD-1) antibody treatment. Mechanistically, disruption of the BRCA1-PALB2 interaction causes persistent high level of DNA damage in HCC cells, leading to activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in both malignant hepatocytes and M1 macrophages in the tumor microenvironment. The activated cGAS-STING pathway induces programmed cell death 1 ligand 1 expression via the STING-interferon regulatory factor 3 (IRF3)-signal transducer and activator of transcription 1 pathway, causing immunosuppression to facilitate tumorigenesis and tumor progression. Meanwhile, M1 macrophages with an activated cGAS-STING pathway could recruit T lymphocytes through the STING-IRF3 pathway, leading to T-lymphocyte infiltration in tumors. After normalizing immune responses by PD-1 antibody treatment, the infiltrating T lymphocytes attack tumor cells rapidly and effectively. This study reveals that persistent DNA damage caused by a defective BRCA pathway induces tumor immunosuppression and T-lymphocyte infiltration in HCC through the cGAS-STING pathway, providing insight into tumor immune microenvironment remodeling that may help improve HCC response to PD-1 antibody treatment.

Nomogram for predicting prognosis of patients with metastatic melanoma after immunotherapy: A Chinese population-based analysis.

Previous studies indicated the evidence that baseline levels of thyroid antibodies, thyroid status, and serum lactate dehydrogenase (LDH) and M stage may influence the prognosis of patients with advanced or metastatic melanoma treated with immune checkpoint inhibitors that targets programmed cell death-1 (PD-1) or programmed death ligand 1, which reported that dramatic improvements in survival rates were observed; however, the presence of controversy has prevented consensus from being reached. Study objectives were to develop a nomogram to identify several prognostic factors in Chinese patients with metastatic melanoma receiving immunotherapy. This retrospective study included 231 patients from Sun Yat-sen University Cancer Center, and patients were split into internal cohort (n = 165) and external validation cohort (n = 66). We developed a nomogram for the prediction of response and prognosis on the basis of the levels of serum thyroid peroxidase antibody (A-TPO), free T3 (FT3), and LDH and M stage that were measured at the baseline of anti-PD-1 infusion. In addition, the follow-up lasted at least until 5 years after the treatment or mortality. RECIST v1.1 was used to classify treatment responses. Chi-square test showed that PD-1 antibody was more effective in patients with melanoma with high level baseline FT4 or earlier M stage. A multivariate Cox analysis showed that baseline FT3 (P = 0.009), baseline A-TPO (P = 0.016), and LDH (P = 0.013) levels and M stage (P < 0.001) independently predicted overall survival (OS) in patients with melanoma. The above factors are integrated, and a prediction model is established, i.e., nomogram. Survival probability area-under-the-curve values of 1, 2, and 3 years in the training, internal validation, and external validation cohorts showed the prognostic accuracy and clinical applicability of nomogram (training: 0.714, 0.757, and 0.764; internal validation: 0.7171963, 0.756549, and 0.7651486; external validation: 0.748, 0.710, and 0.856). In addition, the OS of low-risk (total score ≤ 142.65) versus high-risk (total score > 142.65) patients varied significantly in both training group (P < 0.0001) and external validation cohort (P = 0.0012). According to this study, baseline biomarkers are associated with response to immunotherapy and prognosis among patients with metastatic melanoma. Treatment regimens can be tailor-made on the basis of these biomarkers.

Interval- and cycle-dependent combined effect of STING agonist loaded lipid nanoparticles and a PD-1 antibody

Programmed cell death 1 (PD-1) blockade combination to other drugs have attracted the interest of scientists for treating tumors resistant to PD-1 blockade. In this study, the impact of the interval, order of administration, and number of cycles of immunotherapeutic combination of stimulator of interferon genes (STING) pathway agonist loaded lipid nanoparticle (STING-LNP) and PD-1 antibody for inducing the optimal combined antitumor activity against a melanoma lung metastasis is reported. One cycle had no effect, but two and three cycles resulted in a combinedantitumor effect. The interval between the administration was found to influence the induction of the combined effect. The second and third doses increased the gene expression of the NK cell activation marker, interferon γ (IFN-γ), PD-1 and a ligand of PD-1 (PD-L1), whereas the first dose failed. NK cells in the lung showed an increase in the expression of the activation markers and PD-1 after the second dose. The combined antitumor effect of this combination therapy against melanoma lung metastasis model could be dependent on the interval as well as the number of doses of STING-LNP.These findings suggest the importance of the protocol setting when combining a nano system loaded with an immune adjuvant and PD-1 antibody.

TIRA study: A phase III, multicenter, randomized controlled study of toripalimab plus radical chemoradiotherapy with or without concurrent cisplatin in patients with high-risk locoregionally advanced nasopharyngeal carcinoma.

TPS6101 Background: Patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) suffer a high risk of distant metastasis and require guideline-recommended multimodality therapy. However, cisplatin-based concurrent chemotherapy leads to a high incidence of severe toxicities and low patient compliance, consequently limiting survival improvement. Toripalimab, an immune checkpoint inhibitor targeting programmed cell death 1 (PD-1), has a novel anti-cancer mechanism and mild toxicity spectrum. Robust evidence showed that given toripalimab + gemcitabine-cisplatin (GP) chemotherapy regimen, the median progression-free survival could be markedly improved in patients with recurrent and metastatic NPC. Besides, PD-1 antibody + radiotherapy is also regarded as a promising therapeutic strategy due to the synergistic effect. Therefore, we hypothesized that the de-intensification strategy using toripalimab + induction chemotherapy (IC) followed by radiotherapy alone would obtain equivalent survival and low toxicity in patients with LA-NPC compared with toripalimab + IC followed by concurrent chemoradiotherapy. Methods: TheTIRA study is a multicenter, randomized, controlled, open-label, phase III study. Since August 2021, we have been recruiting high-risk LA-NPC patients (stage III-IVa, except T3-4N0M0 &amp; T3N1M0) from 12 Chinese centers. Our target sample size is temporarily set at 494 patients with 247 for each arm. Patients will be 1:1 ratio randomized to the experimental or control arm. Patients in the experimental arm will receive induction-concurrent toripalimab (240 mg, d1, Q3W × 6 cycle) with IC (gemcitabine 1000 mg/m2, d1 &amp; d8 + cisplatin 80 mg/m2, d1, Q3W × 3 cycle) + intensity-modulated radiotherapy (IMRT, 70 Gy in 33 fractions), and thereafter adjuvant toripalimab (240 mg, d1, Q3W × 11 cycle). Patients in the controlled arm will receive an additional concurrent cisplatin (100 mg/m2, d1, Q3W × 2 cycle). The primary endpoint is the 3-year failure-free survival. Secondary endpoints include 3-year overall survival, 3-year distant metastasis-free survival, 3-year locoregional recurrence-free survival, quality-of-life assessment according to the systems of the European Organization for Research and Treatment of Cancer and the Functional Assessment of Cancer Therapy, and safety profile. Exploratory analysis will be performed for potential biomarkers of survival prediction including PD-L1 expression and tumor-infiltrating lymphocytes. Clinical trial information: NCT04907370.

Intratumoral Anti-PD-1 Nanoformulation Improves Its Biodistribution.

Intratumoral administration of immune checkpoint inhibitors, such as programmed cell death-1 antibodies (aPD-1), is a promising approach toward addressing both the low patients' responses and high off-target toxicity, but good preclinical results have not translated in phase I clinical studies as significant off-target toxicities were observed. We hypothesized that the nanoformulation of aPD-1 could alter both their loco-regional and systemic distribution following intratumoral administration. To test this hypothesis, we developed an aPD-1 nanoformulation (aPD-1 NPs) and investigated its biodistribution following intratumoral injection in an orthotopic mice model of head and neck cancer. Biodistribution analysis demonstrated a significantly lower distribution in off-target organs of the nanoformulated aPD-1 compared to free antibodies. On the other hand, both aPD-1 NPs and free aPD-1 yielded a significantly higher tumor and tumor draining lymph node accumulation than the systemically administrated free aPD-1 used as the current clinical benchmark. In a set of comprehensive in vitro biological studies, aPD-1 NPs effectively inhibited PD-1 expression on T-cells to a similar extent to free aPD-1 and efficiently potentiated the cytotoxicity of T-cells against head and neck cancer cells in vitro. Further studies are warranted to assess the potential of this intratumoral administration of aPD-1 nanoformulation in alleviating the toxicity and enhancing the tumor efficacy of immune checkpoint inhibitors.

Therapeutic Efficacy of an Oncolytic Influenza Virus Carrying an Antibody Against Programmed Cell Death 1 in Hepatocellular Carcinoma.

Oncolytic virus therapy is a promising novel immunotherapy. In this report, we engineered a novel oncolytic influenza virus (IV) carrying an antihuman programmed cell death 1 (PD-1) monoclonal antibody utilizing reverse genetics. A reassortant chimeric IV, named rFlu-huPD1, was synthesized as follows: the heavy chain of the PD-1 antibody was encoded on the PB1 fragment, and the light chain of the PD-1 antibody was encoded on the polymerase acid protein fragment. rFlu-huPD1 antibodies were produced in infected ovalantoic eggs and could replicate to high titers. Moreover, selective cytotoxicity of rFlu-huPD1 was upregulated in multiple hepatocellular carcinoma (HCC) cell lines compared with a control, as determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, the activation of T cells in the spleen of tumor-bearing BALB/c mice treated with rFlu-huPD1 was observed, especially cytotoxic CD8+ T cell activation in vivo. In addition, in a patient-derived xenograft liver cancer mouse model, tumor growth was reduced and the overall survival of the mice was increased by intratumoral injections with rFlu-huPD1 compared with wild-type PR8 virus. Taken together, these findings provide evidence for the utility of a combination of oncolytic IVs expressing PD-1 inhibitors for use in HCC virotherapy.

Conditional Deletion of Pdcd1 Identifies the Cell-Intrinsic Action of PD-1 on Functional CD8 T Cell Subsets for Antitumor Efficacy.

Programmed cell death-1 (PD-1) blockade has a profound effect on the ability of the immune system to eliminate tumors, but many questions remain about the cell types involved and the underlying mechanisms of immune activation. To shed some light on this, the cellular and molecular events following inhibition of PD-1 signaling was investigated in the MC-38 colon carcinoma model using constitutive (PD-1 KO) and conditional (PD1cKO) mice and in wild-type mice treated with PD-1 antibody. The impact on both tumor growth and the development of tumor immunity was assessed. In the PD-1cKO mice, a complete deletion of Pdcd1 in tumor-infiltrating T cells (TILs) after tamoxifen treatment led to the inhibition of tumor growth of both small and large tumors. Extensive immune phenotypic analysis of the TILs by flow and mass cytometry identified 20-different T cell subsets of which specifically 5-CD8 positive ones expanded in all three models after PD-1 blockade. All five subsets expressed granzyme B and interferon gamma (IFNγ). Gene expression analysis of the tumor further supported the phenotypic analysis in both PD-1cKO- and PD-1 Ab-treated mice and showed an upregulation of pathways related to CD4 and CD8 T-cell activation, enhanced signaling through costimulatory molecules and IFNγ, and non-T-cell processes. Altogether, using PD-1cKO mice, we define the intrinsic nature of PD-1 suppression of CD8 T-cell responses in tumor immunity.

CHI3L1 regulates PD-L1 and anti-CHI3L1-PD-1 antibody elicits synergistic antitumor responses.

Evasion of the immune response is a hallmark of cancer, and programmed cell death 1 (PD-1) and PD-1 ligand 1 (PD-L1) are major mediators of this immunosuppression. Chitinase 3-like 1 (CHI3L1) is induced in many cancers, where it portends a poor prognosis and contributes to tumor metastasis and spread. However, the mechanism(s) that CHI3L1 uses in metastasis have not been defined. Here we demonstrate that CHI3L1 regulates the expression of PD-L1, PD-L2, PD-1, LAG3, and TIM3 and plays a critical role in melanoma progression and lymphatic spread. CHI3L1 also contributed to IFN-γ-stimulated macrophage PD-L1 expression, and RIG-like helicase innate immunity suppressed CHI3L1, PD-L1, and melanoma progression. Individual antibodies against CHI3L1 or PD-1 had discrete antitumor effects and additive antitumor responses in metastasis models and T cell-tumor cell cocultures when administered simultaneously. Synergistic cytotoxic tumor cell death was seen in T cell-tumor cell cocultures, and significantly enhanced antitumor responses were seen in in vivo tumor models treated with bispecific antibodies that simultaneously target CHI3L1 and PD-1. CHI3L1 contributes to tumor progression by stimulating the PD-1/PD-L1 axis and other checkpoint molecules. The simultaneous targeting of CHI3L1 and the PD-1/PD-L1 axis with individual and, more powerfully, with bispecific antibodies represents a promising therapy for pulmonary metastasis and progression.

The Programmed Cell Death Ligand-1/Programmed Cell Death-1 Pathway Mediates Pregnancy-Induced Analgesia via Regulating Spinal Inflammatory Cytokines.

BACKGROUND:The maternal pain threshold gradually increases during pregnancy, especially in late pregnancy. A series of mechanisms underlying pregnancy-induced analgesia have been reported. However, these mechanisms are still not completely clear, and the underlying molecular mechanisms need further investigation. We examined the relationship between the antinociceptive effect and the expression level of programmed cell death ligand-1 (PD-L1) during pregnancy and further observed the changes in pain thresholds and expression levels of cytokines in late-pregnant mice before and after blockade of PD-L1 or programmed cell death-1 (PD-1).METHODS:Part 1: Female mice were assigned to 3 groups (nonpregnant, late-pregnant, and postpartum). Part 2: Late-pregnant mice were assigned to 3 treatment groups (control [phosphate buffer solution], RMP1-14 [mouse anti–PD-1 antibody], and soluble PD-1 [sPD-1]). Behavioral testing (mechanical and thermal) and tissue (serum and spinal cord) analysis were performed on all groups. PD-L1, interleukin (IL)-10, tumor necrosis factor-α (TNF-α), and IL-6 expression levels in tissue were examined via reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blot analysis.RESULTS:The mechanical and thermal pain thresholds were significantly increased in late pregnancy and decreased after delivery. PD-L1 expression was also elevated in late pregnancy and decreased after delivery. In addition, in the late stage of gestation, the maternal inflammatory microenvironment was dominated by anti-inflammatory factors. After administration of RMP1-14 or sPD-1, the pain thresholds of late-pregnant mice were significantly reduced. In late-pregnant mice, the high level of IL-10 was obviously reduced, and the low levels of TNF-α and IL-6 were elevated.CONCLUSIONS:The PD-L1/PD-1 pathway mediates pregnancy-induced analgesia, partially via the regulation of cytokines.

SY23-4 Combination therapy with immune checkpoint inhibitor and targeted agents in metastatic TNBC and HR-positive breast cancer

In recent years, immune checkpoint inhibitors targeting the programmed cell death-1 (PD-1) pathway have been developed for various cancer types. The IMpassion 130 study demonstrated the efficacy and safety of atezolizumab, a programmed cell death ligand-1 (PD-L1) antibody, plus nab-paclitaxel for patients with PD-L1-positive triple-negative breast cancer (TNBC). However, IMpassion 131 study did not demonstrate the efficacy of atezolizumab plus paclitaxel for patients with PD-L1-positive TNBC. Now the discussion of optimal combination strategy is getting more interesting and challenging. On the other hand, hormone receptor-positive BC and PD-L1-negative TNBC are less sensitive than PD-L1-positive TNBC to immune checkpoint inhibitors. Novel combinations of multiple classes of drugs are under evaluation. Anti-VEGF antibody or in combination with PD-1 antibody is evaluated in various cancer types, and the strategy is also promising in hormone receptor-positive BC and PD-L1-negative TNBC. Combination therapy of CDK4/6 inhibitor and PD-1/L-1 antibody is also a potential strategy in hormone receptor(HR)-positive, HER2-negative metastatic BC. We discuss future perspective of immunotherapy in combination with targeted agents in metastatic TNBC and also HR-positive breast cancer.