Combination regimens with PD-1/PD-L1 immune checkpoint inhibitors for gastrointestinal malignancies

PD-1/PD-L1 axis: implications in immune regulation, cancer progression, and translational applications

The PD-1/PD-L1 axis is a complex signaling pathway that has an important role in the immune system cells. Programmed cell death protein 1 (PD-1) acts as an immune checkpoint on the T lymphocytes, B lymphocytes, natural killer (NK), macrophages, dendritic cells (DCs), monocytes, and myeloid cells. Its ligand, the programmed cell death 1 ligand (PD-L1), is expressed in the surface of the antigen-presenting cells (APCs). The binding of both promotes the downregulation of the T cell response to ensure the activation to prevent the onset of chronic immune inflammation. This axis in the tumor microenvironment (TME) performs a crucial role in the tumor progression and the escape of the tumor by neutralizing the immune system, the engagement of PD-L1 with PD-1 in the T cell causes dysfunctions, neutralization, and exhaustion, providing the tumor mass production. This review will provide a comprehensive overview of the functions of the PD-1/PD-L1 system in immune function, cancer, and the potential therapeutic implications of the PD-1/PD-L1 pathway for cancer management.

An investigator-initiated clinical study in patients with refractory or recurrent solid tumors: 'R-ISV-FOLactis' trial

Aim: In situ vaccination, a kind of therapeutic cancer vaccine, can be realized by radiotherapy and intratumoral immune injection. This study combines intratumoral injection, radiotherapy and PD-1 blockade for synergistic antitumor effect. Materials & methods: Patients with advanced solid tumors who are unresponsive or intolerant to standard treatment will be treated with hypofractionated radiotherapy, intratumoral injection of FOLactis, PD-1 blockade. The primary end point is to observe the efficacy and safety, with the secondary end point to evaluate abscopal effects and the correlation between the immunological rationale and efficacy. Discussion: The combined regimen will be utilized to trigger antitumor immunity and is expected to be feasible and effective and provide a novel option for the comprehensive treatment of cancer.Clinical Trial Registration: ChiCTR2200060660 (ChiCTR.gov.cn).

Efficacy and biomarker analysis of second-line nab-paclitaxel plus sintilimab in patients with advanced biliary tract cancer

Biliary tract cancer (BTC) is a highly aggressive malignancy with limited second-line therapy. We conducted this phase 2 trial to evaluate the efficacy and safety of second-line nab-paclitaxel plus sintilimab in advanced BTC. Histologically confirmed advanced BTC patients with documented disease progression after first-line chemotherapy were enrolled. Subjects received nab-paclitaxel 125 mg/m2 on days 1 and 8 plus sintilimab 200 mg on day 1, administered every 3 weeks. The primary end point was the objective response rate (ORR). The secondary end points were progression-free survival (PFS), overall survival (OS), and adverse reactions. Simultaneously, next-generation sequencing, programmed cell death ligand 1 immunohistochemistry and multiplex immunofluorescence of tumor-infiltrating lymphocytes were applied to explore potential biomarkers. Twenty-six subjects were consecutively enrolled. The ORR was 26.9% (7/26), including two complete responses and five partial responses, which met the primary end point. The disease control rate was 61.5% (16/26). The median PFS was 169 days (about 5.6 months, 95% confidence interval [CI] 60-278 days). The median OS was 442 days (about 14.7 months, 95% CI 298-586 days). Grade 3 treatment-related adverse events (TRAEs) were mainly anemia (27%), leukopenia (23%), neutropenia (19%), and peripheral sensory neuropathy (8%). No grade 4 or 5 TRAEs occurred. Biomarker analysis suggested that positive PD-L1 and high proportions of CD8+ T-cell infiltration were correlated with improved clinical outcome. Nab-paclitaxel plus sintilimab is a potentially effective and tolerable second-line regimen for advanced BTC that deserves to be studied in large-scale trials. PD-L1 status and CD8+ T cell infiltration might be promising biomarkers for efficacy prediction.

SIRPG expression positively associates with an inflamed tumor microenvironment and response to PD-1 blockade

BACKGROUND

This study aimed to investigate the relationship between signal regulatory protein gamma (SIRPG) and tumor immune microenvironment phenotypes or T cell mediated-adaptive antitumor immunity, and its predictive value for response to PD-1 blockade in cancers.

METHODS

Pan-cancer analysis of SIRPG expression and immune deconvolution was performed using transcriptomic data across 33 tumor types. Transcriptomic and clinical data from 157 patients with non-small-cell lung cancer (NSCLC) and melanoma received PD-1 blockade were analyzed. Expression characteristics of SIRPG were investigated using single-cell RNA sequencing (scRNA-seq) data of 103,599 cells. The effect of SIRPG expression was evaluated via SIRPG knockdown or overexpression in Jurkat T cells.

RESULTS

The results showed that most cancers with high SIRPG expression had significantly higher abundance of T cells, B cells, NK cells, M1 macrophages and cytotoxic lymphocytes and increased expression level of immunomodulatory factors regulating immune cell recruitment, antigen presentation, T cell activation and cytotoxicity, but markedly lower abundance of neutrophils, M2 macrophages, and myeloid-derived suppressor cells. High SIRPG expression was associated with favorable response to PD-1 blockade in both NSCLC and melanoma. scRNA-seq data suggested SIRPG was mainly expressed in CD8+ exhausted T and CD4+ regulatory T cells, and positively associated with immune checkpoint expression including PDCD1 and CTLA4. In vitro test showed SIRPG expression in T cells could facilitate expression of PDCD1 and CTLA4.

CONCLUSION

High SIRPG expression is associated with an inflamed immune phenotype in cancers and favorable response to PD-1 blockade, suggesting it would be a promising predictive biomarker for PD-1 blockade and novel immunotherapeutic target.

Neoadjuvant immunotherapy based on PD-1/L1 inhibitors for gastrointestinal tumors: a review of the rationale and clinical advances

The landscape of current tumor treatment has been revolutionized by the advent of immunotherapy based on PD-1/PD-L1 inhibitors. Leveraging its capacity to mobilize systemic antitumor immunity, which is primarily mediated by T cells, there is growing exploration and expansion of its potential value in various stages of clinical tumor treatment. Neoadjuvant immunotherapy induces a robust immune response against tumors prior to surgery, effectively facilitating tumor volume reduction, early eradication or suppression of tumor cell activity, and control of potential metastatic spread, to improve curative surgical resection rates, and prevent tumor recurrence. This review delineates the theoretical basis of neoadjuvant immunotherapy from preclinical research evidence, discusses specific challenges in clinical application, and provides a comprehensive overview of clinical research progress in neoadjuvant immunotherapy for gastrointestinal tumors. These findings suggest that neoadjuvant immunotherapy has the potential to ameliorate immunosuppressive states and enhance cytotoxic T cell function while preserving lymphatic drainage in the preoperative period. However, further investigations are needed on specific treatment regimens, suitable patient populations, and measurable endpoints. Despite numerous studies demonstrating the promising efficacy and manageable adverse events of neoadjuvant immunotherapy in gastrointestinal tumors, the availability of high-quality randomized controlled trials is limited, which highlights the necessity for further research.

Immune checkpoint inhibitors in gastrointestinal malignancies: an Umbrella review

In the Modern era, immune checkpoint inhibitors (ICIs) have been the cornerstone of success in the treatment of several malignancies. Despite remarkable therapeutic advances, complex matrix together with significant molecular and immunological differences have led to conflicting outcomes of ICI therapy in gastrointestinal (GI) cancers. As far we are aware, to date, there has been no study to confirm the robustness of existing data, and this study is the first umbrella review to provide a more comprehensive picture about ICIs' efficacy and safety in GI malignancies. Systematic search on PubMed, Scopus, Web of Science, EMBASE, and Cochrane library identified 14 meta-analyses. The pooled analysis revealed that ICIs application, especially programmed death-1 (PD-1) inhibitors such as Camrelizumab and Sintilimab, could partially improve response rates in patients with GI cancers compared to conventional therapies. However, different GI cancer types did not experience the same efficacy; it seems that hepatocellular carcinoma (HCC) and esophageal cancer (EC) patients are likely better candidates for ICI therapy than GC and CRC patients. Furthermore, application of ICIs in a combined-modal strategy are perceived opportunity in GI cancers. We also assessed the correlation of PD-L1 expression as well as microsatellite status with the extent of the response to ICIs; overall, high expression of PD-L1 in GI cancers is associated with better response to ICIs, however, additional studies are required to precisely elaborate ICI responses with respect to microsatellite status in different GI tumors. Despite encouraging ICI efficacy in some GI cancers, a greater number of serious and fatal adverse events have been observed; further highlighting the fact that ICI therapy in GI cancers is not without cost, and further studies are required to utmost optimization of this approach in GI cancers.

Clinical efficacy and safety evaluation of camrelizumab plus lenvatinib in adjuvant therapy after hepatocellular carcinoma surgery

Objective

To assess the efficacy and safety of camrelizumab plus different targeted drugs in adjuvant therapy after hepatocellular carcinoma (HCC) surgery.

Patients and methods

This retrospective cohort study included HCC patients who, after undergoing failed postoperative adjuvant lenvatinib therapy, received intravenous camrelizumab 200 mg every 3 weeks (C group, n = 97), camrelizumab plus oral apatinib 250 mg daily (C+A group, n = 125), camrelizumab plus oral lenvatinib 12 mg daily (for bodyweight ≥60 kg)/lenvatinib 8 mg daily (for bodyweight <60 kg) (C+L group, n = 120), or camrelizumab plus oral sorafenib 400 mg bi-daily (C+S group, n = 114) between October 2020 and October 2021. The outcomes including the objective response rate (ORR) and disease control rate (DCR) were evaluated by RECIST 1.1 and iRECIST. The median progression-free survival (mPFS), median overall survival (mOS), 6-month OS rate, 12-month OS rate, and adverse events were evaluated.

Results

As of 31 May 2022 with last follow-up time, the ORR was 17.2% for the C group, 44.6% for the C+A group, 47.9% for the C+L group, and 36.3% for the C+S group. The DCR was 72.0% for the C group, 81.8% for the C+A group, 85.5% for the C+L group, and 77.9% for the C+S group. The mPFS was 11.0 months (10.1-12.8) for the C group, 14.0 months (12.7-16.5) for the C+A group, 18.0 months (16.9-20.1) for the C+L group, and 12.0 months (9.7-14.4) for the C+S group. The mOS was 13.0 months (11.6-15.3) for the C group, 17.0 months (15.8-19.4) for the C+A group, 19.0 months (17.7-20.2) for the C+L group, and 15.0 months (14.1-17.3) for the C+S group. Grade 3 or 4 treatment-related adverse events occurred in 14 patients (14.4%) for the C group, 10 patients (8.0%) for the C+A group, 5 patients (4.2%) for the C+L group, and 11 patients (9.6%) for the C+S group. The most common adverse events were fatigue and transaminitis.

Conclusion

Camrelizumab combined with lenvatinib as adjuvant therapy showed promising efficacy and manageable safety in HCC patients. It might be a potential adjuvant therapy or second-line treatment for these patients.

A target map of clinical combination therapies in oncology: an analysis of clinicaltrials.gov

Combination therapies have taken center stage for cancer treatment, however, there is a lack of a comprehensive portrait to quantitatively map the current clinical combination progress. This study aims to capture clinical combination therapies of the validated FDA-approved new oncology drugs by a macro data analysis and to summarize combination mechanisms and strategies in the context of the existing literature. A total of 72 new molecular entities or new therapeutic biological products for cancer treatment approved by the FDA from 2017 to 2021 were identified, and the data on their related 3334 trials were retrieved from the database of ClinicalTrials.gov. Moreover, these sampled clinical trials were refined by activity status and combination relevance and labeled with the relevant clinical arms and drug combinations, as well as drug targets and target pairs. Combination therapies are increasingly prevalent in clinical trials of new oncology drugs. From retrospective work, existing clinical combination therapies in oncology are driven by different patterns (i.e., rational design and industry trends). The former can be represented by mechanism-based or structure-based combinations, such as targeting different domains of HER2 protein or in-series co-targeting in RAF plus MEK inhibitors. The latter is an empirically driven strategy, including redundant combinations in hot targets, such as PD-1/PD-L1, PI3K, CDK4/6, and PARP. Because of an explosion in the number of clinical trials and the resultant shortage of available patients, it is essential to rationally design drug combinations.

Kinome-wide CRISPR-Cas9 knockout screens revealed PLK1 as a therapeutic target for osteosarcoma

Osteosarcoma is the most common malignant bone tumor, tending to be aggressive and recurrent. The therapeutic development for treating osteosarcoma has been largely hampered by the lack of effective and specific targets. Using kinome-wide CRISPR-Cas9 knockout screens, we systematically revealed a cohort of kinases essential for the survival and growth of human osteosarcoma cells, in which Polo-like kinase 1 (PLK1) appeared as a specific prominent hit. PLK1 knockout substantially inhibited proliferation of osteosarcoma cells in vitro and the tumor growth of osteosarcoma xenograft in vivo. Volasertib, a potent experimental PLK1 inhibitor, can effectively inhibit the growth of the osteosarcoma cell lines in vitro. It can also disrupt the development of tumors in the patient-derived xenograft (PDX) models in vivo. Furthermore, we confirmed that the mode of action (MoA) of volasertib is primarily mediated by the cell-cycle arrest and apoptosis triggered by DNA damage. As PLK1 inhibitors are entering phase III clinical trials, our findings provide important insights into the efficacy and MoA of the relevant therapeutic approach for combating osteosarcoma.

GHRL as a prognostic biomarker correlated with immune infiltrates and progression of precancerous lesions in gastric cancer

Objective

Ghrelin is a protein that regulate appetite and energy balance in the human body, which is encoded by the ghrelin prepropeptide gene (GHRL). GHRL is linked with carcinogenesis and immune regulation. However, the correlation of GHRL to prognosis and tumor-infiltrating lymphocytes in gastric cancer (GC) remains unclear.

Methods

In this study, we assessed the transcriptional expression, prognosis, and different clinicopathological features about GHRL and the correlation between GHRL and tumor infiltration immune cells in GC patients based on the data published in the following databases: TIMER, GEPIA, GEO, STRING, UALCAN, TISIDB, and Kaplan-Meier Plotter. Furthermore, R software analysis for GC Correa' cascade was also provided. Finally, GHRL expression in GC tissues was assayed using quantitative real-time polymerase chain reaction and immunohistochemistry.

Results

We found that GHRL expression in GC samples was lower than in normal samples and verified by quantitative PCR (qPCR) and immunohistochemistry. However, sample type, cancer stage, and worse survival were correlated to high GHRL expression. We also found that the expression of GHRL in dysplasia was significantly lower than that in CNAG and in GC. High GHRL expression was connected with immunomodulators, chemokines, and infiltrating levels of B cells, CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells in GC.

Conclusions

GHRL is a prognostic biomarker for GC patients, and it is correlated with progression of precancerous lesions in GC. It might lead to poor prognosis by regulating tumor immune microenvironment. Studies are important to explore therapeutic targeting GHRL in the future.

Molecular Farming of Pembrolizumab and Nivolumab

Immune checkpoint inhibitors (ICIs) are a class of immunotherapy agents capable of alleviating the immunosuppressive effects exerted by tumorigenic cells. The programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint is one of the most ubiquitous checkpoints utilized by tumorigenic cells for immune evasion by inducing apoptosis and inhibiting the proliferation and cytokine production of T lymphocytes. Currently, the most frequently used ICIs targeting the PD-1/PD-L1 checkpoint include monoclonal antibodies (mAbs) pembrolizumab and nivolumab that bind to PD-1 on T lymphocytes and inhibit interaction with PD-L1 on tumorigenic cells. However, pembrolizumab and nivolumab are costly, and thus their accessibility is limited in low- and middle-income countries (LMICs). Therefore, it is essential to develop novel biomanufacturing platforms capable of reducing the cost of these two therapies. Molecular farming is one such platform utilizing plants for mAb production, and it has been demonstrated to be a rapid, low-cost, and scalable platform that can be potentially implemented in LMICs to diminish the exorbitant prices, ultimately leading to a significant reduction in cancer-related mortalities within these countries.

A bispecific antibody AP203 targeting PD-L1 and CD137 exerts potent antitumor activity without toxicity

BACKGROUND

Bispecific antibody has garnered considerable attention in the recent years due to its impressive preliminary efficacy in hematological malignancies. For solid tumors, however, the main hindrance is the suppressive tumor microenvironment, which effectively impedes the activation of infiltrating T cells. Herein, we designed a bispecific antibody AP203 with high binding affinity to PD-L1 and CD137 and assessed its safety and anti-tumor efficacy, as well as explored the mechanism of action.

METHODS

The optimal antibody binders against PD-L1 and CD137 were screened from the OmniMab phagemid library. The binding affinity of the constructed AP203 were evaluated using enzyme-linked immunosorbent assay (ELISA) and biolayer interferometry (BLI). T-cell stimulatory capacity was assessed using the allogeneic mixed lymphocyte reaction (MLR), antigen-specific recall response, and coculture with PD-L1-expressing cells. In vivo antitumor efficacy was evaluated using two models of tumor-xenografted humanized mice with profiling of tumor infiltrating lymphocytes (TILs). The possible toxicity of AP203 was examined using in vitro cytokine release assay by human PBMCs.

RESULTS

AP203, which simultaneously targeted PD-L1 and costimulatory CD137, elicit superior agonistic effects over parental antibodies alone or in combination in terms of T cell activation, enhanced memory recall responses, and overcoming Treg-mediated immunosuppression (P < 0.05). The agonistic activity of AP203 was further demonstrated PD-L1-dependent by coculturing T cells with PD-L1-expressing cells. In vivo animal studies using immunodeficient or immunocompetent mice both showed a dose-related antitumor efficacy superior to parental antibodies in combination (P < 0.05). Correspondingly, AP203 significantly increased tumor infiltrating CD8 + T cells, while decreased CD4 + T cells, as well as Treg cells (P < 0.05), resulting in a dose-dependent increase in the CD8 + /CD4 + ratio. Moreover, either soluble or immobilized AP203 did not induce the production of inflammatory cytokines by human PBMCs.

CONCLUSIONS

AP203 exerts potent antitumor activity not only by blocking PD-1/PD-L1 inhibitory signaling, but also by activating CD137 costimulatory signaling in effector T cells that consequently counteracts Treg-mediated immunosuppression. Based on promising preclinical results, AP203 should be a suitable candidate for clinical treatment of solid tumors.

Targeting MYC in combination with epigenetic regulators induces synergistic anti-leukemic effects in MLLr leukemia and simultaneously improves immunity

MLL rearranged (MLLr) leukemias are associated with a poor prognosis and a limited response to conventional therapies. Moreover, chemotherapies result in severe side effects with significant impairment of the immune system. Therefore, the identification of novel treatment strategies is mandatory. Recently, we developed a human MLLr leukemia model by inducing chromosomal rearrangements in CD34+ cells using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9. This MLLr model authentically mimics patient leukemic cells and can be used as a platform for novel treatment strategies. RNA sequencing of our model revealed MYC as one of the most important key drivers to promote oncogenesis. However, in clinical trials the BRD4 inhibitor JQ-1 leading to indirect blocking of the MYC pathway shows only modest activity. We and others previously reported that epigenetic drugs targeting MAT2A or PRMT5 promote cell death in MLLr cells. Therefore, we use these drugs in combination with JQ-1 leading to augmented anti-leukemic effects. Moreover, we found activation of T, NK and iNKT cells, release of immunomodulatory cytokines and downregulation of the PD-1/PD-L1 axis upon inhibitor treatment leading to improved cytotoxicity. In summary, the inhibition of MYC and MAT2A or PRMT5 drives robust synergistic anti-leukemic activity in MLLr leukemia. Moreover, the immune system is concomitantly activated upon combinatorial inhibitor treatment, hereby further augmenting the therapeutic efficiency.

Photodynamic Opening of the Blood-Brain Barrier and the Meningeal Lymphatic System: The New Niche in Immunotherapy for Brain Tumors

Photodynamic therapy (PDT) is a promising add-on therapy to the current standard of care for patients with glioblastoma (GBM). The traditional explanation of the anti-cancer PDT effects involves the PDT-induced generation of a singlet oxygen in the GBM cells, which causes tumor cell death and microvasculature collapse. Recently, new vascular mechanisms of PDT associated with opening of the blood-brain barrier (OBBB) and the activation of functions of the meningeal lymphatic vessels have been discovered. In this review, we highlight the emerging trends and future promises of immunotherapy for brain tumors and discuss PDT-OBBB as a new niche and an important informative platform for the development of innovative pharmacological strategies for the modulation of brain tumor immunity and the improvement of immunotherapy for GBM.

Characteristics of appendicitis after immune checkpoint inhibitor therapy among cancer patients

PURPOSE

Immune checkpoint inhibitor (ICI) therapy has revolutionized cancer care but is associated with immune-related adverse events (irAEs). Recent case reports raised the concern that acute appendicitis may be an irAE. In this study, we sought to describe the disease course of post-ICI therapy appendicitis and its associated complications.

METHODS

Adult patients who had an International Classification of Diseases code for appendicitis within the first 2 years after initiating ICI therapy from January 2010 to April 2021 and who had imaging evidence of appendicitis were studied retrospectively.

RESULTS

13,991 patients were identified who had ICI exposure during the study period, 44 had codes for appendicitis, 10 of whom met the inclusion criteria. Their median age at the time of diagnosis was 59 years. The median time from ICI therapy initiation to appendicitis onset was 188 days. The most common presenting symptoms were abdominal pain (70%) and fever (40%). Abscesses were present in two patients, and a perforation was present in one. All 10 patients received broad-spectrum antibiotics. Five patients needed surgery or interventional radiology drainage. Nine patients had resolution of appendicitis symptoms after treatment.

CONCLUSION

Post-ICI therapy appendicitis is rare but presents similarly to and has similar complications rates as conventional appendicitis. Appendectomy remains the mainstay of treatment, but its use can be limited in cancer patients. The decision to continue ICI therapy remains at the discretion of the clinician. Further studies are needed to bring awareness to and advance the understanding of this clinical entity.

BET bromodomain inhibition rescues PD-1-mediated T-cell exhaustion in acute myeloid leukemia

Sustained expression of programmed cell death receptor-1 (PD-1) is correlated with the exhaustion of T cells, and blockade of the PD-1 pathway is an effective immunotherapeutic strategy for treating various cancers. However, response rates are limited, and many patients do not achieve durable responses. Thus, it is important to seek additional strategies that can improve anticancer immunity. Here, we report that the bromodomain and extraterminal domain (BET) inhibitor JQ1 inhibits PD-1 expression in Jurkat T cells, primary T cells, and T-cell exhaustion models. Furthermore, JQ1 dramatically impaired the expression of PD-1 and T-cell immunoglobulin mucin-domain-containing-3 (Tim-3) and promoted the secretion of cytokines in T cells from patients with acute myeloid leukemia (AML). In line with that, BET inhibitor-treated CD19-CAR T and CD123-CAR T cells have enhanced anti-leukemia potency and resistant to exhaustion. Mechanistically, BRD4 binds to the NFAT2 and PDCD1 (encoding PD-1) promoters, and NFAT2 binds to the PDCD1 and HAVCR2 (encoding Tim-3) promoters. JQ1-treated T cells showed downregulated NFAT2, PD-1, and Tim-3 expression. In addition, BET inhibitor suppressed programmed death-ligand 1 (PD-L1) expression and cell growth in AML cell lines and in primary AML cells. We also demonstrated that JQ1 treatment led to inhibition of leukemia progression, reduced T-cell PD-1/Tim-3 expression, and prolonged survival in MLL-AF9 AML mouse model and Nalm6 (B-cell acute lymphoblastic leukemia cell)-bearing mouse leukemia model. Taken together, BET inhibition improved anti-leukemia immunity by regulating PD-1/PD-L1 expression, and also directly suppressed AML cells, which provides novel insights on the multiple effects of BET inhibition for cancer therapy.

Lenvatinib Combined With a PD-1 Inhibitor as Effective Therapy for Advanced Intrahepatic Cholangiocarcinoma

Background: Lenvatinib combined with a PD-1 inhibitor has obtained a satisfactory antitumor effect in several solid tumors. However, the efficacy and tumor response of lenvatinib with a PD-1 inhibitor in advanced intrahepatic cholangiocarcinoma still need further exploration. Methods: This is a single-arm study for the assessment of the efficacy and tolerability of lenvatinib with a PD-1 inhibitor in intrahepatic cholangiocarcinoma patients who had chemotherapy failure. Efficacy was evaluated based on the Response Evaluation Criteria in Solid Tumors RECIST Version 1.1 (RECIST 1.1). Results: A total of 40 patients with advanced intrahepatic cholangiocarcinoma were enrolled after the chemorefractory effect. The median progression-free survival was 5.83 ± 0.76 months. The 3-month and 6-month progression-free survival rates were 80.0% and 32.5%, respectively. The median overall survival was 14.30 ± 1.30 months. The 12-month and 18-month overall survival rates were 61.4% and 34.7%. The 3-month RECIST 1.1 evaluation was that seven patients (17.5%) showed partial response, 23 patients (57.5%) had stable disease, and 10 patients (25.0%) had progressive disease. The objective response rate was 17.5%, and the disease control rate was 75.0%. All the recorded any-grade adverse events inducing treatment termination were controllable, and there were no AE-related deaths. Conclusion: Our study showed that a combination of lenvatinib with the PD-1 inhibitor could be an effective treatment for advanced intrahepatic cholangiocarcinoma after the chemorefractory effect.

Efficacy and Safety of Anti-PD1/PDL1 in Advanced Biliary Tract Cancer: A Systematic Review and Meta-Analysis

Background

Anti-programmed cell death protein 1 and its ligand (anti-PD1/PDL1) have been proposed as a promising therapeutic option for advanced biliary tract cancer (aBTC). Given the scarce quantitative analyses of anti-PD1/PDL1 in aBTC, we thus did a meta-analysis to assess the benefits and risks of this emerging treatment strategy in patients with aBTC.

Methods

PubMed, Embase, the Cochrane Library, Web of Science, and meeting resources were searched for relevant studies. The main endpoints were median progression-free survival (mPFS), median overall survival (mOS), objective response rate (ORR), disease control rate (DCR), any-grade adverse events (AEs), and grade 3-4 AEs.

Results

Twenty-eight studies with 1,338 participants were included. The best curative effect was found in the anti-PD1/PDL1 combined with anti-CTLA4 and chemotherapy group (mPFS: 12.4 months; mOS: 16.0 months; ORR: 45.1%; DCR: 95.0%), followed by the anti-PD1/PDL1 plus chemotherapy group (mPFS: 8.2 months; mOS: 14.8 months; ORR: 36.3%; DCR: 84.6%), the anti-PD1/PDL1 plus antiangiogenesis group (mPFS: 4.9 months; mOS: 10.2 months; ORR: 17.5%; DCR: 68.7%), the anti-PD1/PDL1 plus anti-cytotoxic T lymphocyte antigen 4 (anti-CTLA4) group (mPFS: 2.9 months; mOS: 8.3 months; ORR: 9.9%; DCR: 36.8%), and the anti-PD1/PDL1 monotherapy group (mPFS: 2.5 months; mOS: 7.6 months; ORR: 6.8%; DCR: 34.7%). Compared with anti-PD1-containing regimens, anti-PDL1-containing regimens achieved preferable mPFS (11.1 vs. 3.8 months), mOS (12.2 vs. 9.8 months), and ORR (23.7% vs. 17.4%), despite a similar DCR (61.1% vs. 61.3%). The mPFS, mOS, ORR, and DCR were 10.6 months, 15.8 months, 42.3%, and 88.6% of first-line anti-PD1/PDL1 and 3.0 months, 9.1 months, 11.6%, and 51.1% of second-line therapy or beyond, respectively. There were 80.6% and 34.0% of the patients suffering any-grade AEs and grade 3-4 AEs. Anti-PD1/PDL1 monotherapy might be considered as a safer alternative than combination regimens. Meanwhile, obvious toxicities in the first-line setting could not be neglected.

Conclusions

Anti-PD1/PDL1 showed encouraging efficacy and acceptable safety profile in aBTC and, thus, could be an alternative treatment.

The Role of NcRNAs to Regulate Immune Checkpoints in Cancer

At present, the incidence of cancer is becoming more and more common, but its treatment has always been a problem. Although a small number of cancers can be treated, the recurrence rates are generally high and cannot be completely cured. At present, conventional cancer therapies mainly include chemotherapy and radiotherapy, which are the first-line therapies for most cancer patients, but there are palliatives. Approaches to cancer treatment are not as fast as cancer development. The current cancer treatments have not been effective in stopping the development of cancer, and cancer treatment needs to be imported into new strategies. Non-coding RNAs (ncRNAs) is a hot research topic at present. NcRNAs, which include microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), participate in all aspects of cancer biology. They are involved in the progression of tumors into a new form, including B-cell lymphoma, glioma, or the parenchymal tumors such as gastric cancer and colon cancer, among others. NcRNAs target various immune checkpoints to affect tumor proliferation, differentiation, and development. This might represent a new strategy for cancer treatment.

Prognostic factors of recurrent intrahepatic cholangiocarcinoma after hepatectomy: A retrospective study

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is a highly malignant tumour. Hepatectomy is an effective treatment for early ICC, but postoperative recurrence greatly affects patient survival. Studies on recurrent ICC after hepatectomy are lacking.

AIM

To investigate the clinical characteristics of patients with recurrent ICC after hepatectomy, analyse prognostic factors and explore diagnosis and treatment strategies.

METHODS

A retrospective analysis was performed on all ICC patients undergoing hepatectomy from January 2013 to August 2021. Patients with postoperative recurrence were selected according to the inclusion and exclusion criteria. Cumulative overall survival was plotted by the Kaplan-Meier method, and differences were assessed by univariate survival analysis using the log-rank test. Multivariate analysis of cumulative survival was performed using the Cox proportional risk model.

RESULTS

During the 8-year study period, 103 patients underwent ICC-related hepatectomy, and 54 exhibited postoperative recurrence. The median disease-free survival (DFS) was 6 mo, the median overall survival (OS) was 9 mo, and the cumulative OS rates at 1, 2 and 3 years after the operation were 40.7%, 14.8% and 7.4%, respectively. The median OS after recurrence was 4 mo, and the cumulative OS rates at 1, 2 and 3 years after recurrence were 16.1%, 6.7% and 3.4%, respectively. Multivariate analysis showed that alcohol consumption [hazard ratio (HR) = 4.64, 95% confidence interval (CI): 1.53-14.04, P = 0.007] and DFS < 6 mo (HR = 3.47, 95%CI: 1.59-7.60, P = 0.002) were independent risk factors for the cumulative survival of patients with recurrence, while treatment after recurrence (HR = 0.21, 95%CI: 0.08-0.55, P = 0.001) was an independent protective factor. The median OS time of patients receiving multimodality therapy after recurrence of ICC was 7 mo, which was significantly higher than that of patients receiving only local therapy (3 mo), patients receiving systematic therapy (4 mo) and patients receiving the best supportive therapy (1 mo). Patients with recurrent ICC who received multimodality therapy had a significantly better long-term survival after recurrence than those who did not (P = 0.026).

CONCLUSION

The prognosis of patients with recurrence after ICC-related hepatectomy is poor. Alcohol consumption and DFS < 6 mo are independent risk factors in terms of the cumulative survival of patients with recurrence, while treatment after recurrence is an independent protective factor. Multimodality therapy can effectively improve the prognosis of patients.

Safety and efficacy of atezolizumab with obinutuzumab and bendamustine in previously untreated follicular lymphoma

Obinutuzumab (G) chemoimmunotherapy demonstrated improved progression-free survival (PFS) vs rituximab-based chemoimmunotherapy in patients with previously untreated follicular lymphoma (FL) in the GALLIUM trial. Atezolizumab (atezo) is a programmed death-ligand 1 inhibitor with a complementary mechanism of action to G by restoring cytotoxic T-cell function. We evaluated the safety and efficacy of atezo-G-bendamustine in patients with previously untreated FL in a phase Ib/II trial (#NCT02596971). A safety run-in phase was followed by an expansion phase with atezo-G-bendamustine induction and atezo-G maintenance for ≤24 months. Forty patients with previously untreated FL were enrolled and treated with atezo-G-bendamustine. The primary endpoint, complete response (CR) rate, assessed by an independent review committee (IRC; modified Lugano 2014 criteria) was 75.0% (95% confidence interval [CI], 61.3% to 85.8%). Three-year investigator-assessed PFS and overall survival rates were 80.9% (95% CI, 63.9% to 90.5%) and 89.3% (95% CI, 73.9% to 95.9%), respectively. At baseline, 21/40 patients had circulating lymphoma-specific clonotypes and underwent repeat testing at end of induction; all were minimal residual disease negative (10-5 sensitivity), with 16 (76.2%) CRs, 3 (14.3%) partial responses, and 2 (9.5%) with stable disease (IRC assessed). Grade 5 (fatal) adverse events (AEs) were reported in 5 patients. The efficacy of atezo-G-bendamustine in previously untreated FL did not appear superior to G-bendamustine efficacy as seen in the GALLIUM trial, and the addition of atezo to G-bendamustine was associated with an increased risk of AEs. Particularly due to the unfavorable safety profile, this regimen cannot be recommended in patients with previously untreated FL. This trial was registered at www.clinicaltrials.gov as #NCT02596971.

Camrelizumab Combined With Gemcitabine and Albumin-Bound Paclitaxel for Neoadjuvant Therapy in the Treatment of Progressive Gallbladder Cancer: A Case Report

Background

The roles of immune checkpoint inhibitors in the treatment of gallbladder cancer are still unclear and challenged by controversial findings. Recent research has shown that immune checkpoint inhibitors in combination with chemotherapy may alleviate disease progression.

Case Summary

A 45-year-old female patient with gallbladder cancer accompanied by multiple abdominal lymph node metastasis was treated with camrelizumab combined with paclitaxel for injection (albumin-bound) and gemcitabine (AG) to downstage the tumor before a radical surgery could be performed. The postoperative quality of life was superior to the preoperative level.

Conclusion

Camrelizumab + AG offers a new therapeutic option for gallbladder cancer with multiple abdominal lymph node metastasis, which, however, warrants further validation in clinical trials.

Recurrent Gallbladder Carcinoma With pMMR/MSS Achieved a Complete Response Following Camrelizumab Combined With Apatinib: A Case Report

Gallbladder carcinoma (GBC) with proficient mismatch repair (pMMR)/microsatellite stable (MSS) is associated with limited response to programmed death-1 (PD-1) inhibitor monotherapy. Limited data of PD-1 blockade combined with anti-angiogenic therapy in GBC are reported. One recurrent GBC patient with pMMR/MSS was treated with camrelizumab plus apatinib. After 4 cycles of combination therapy, the patient achieved a durable complete response with manageable toxicity. The next-generation sequencing and immunohistochemistry analysis showed that tumor mutation burden (TMB) was 7.26 mutants/Mb and PD-L1 expression was 10% (tumor proportion score) and 20% (immune proportion score). This case suggests that camrelizumab in combination with apatinib may be an effective treatment option for GBC patients with pMMR/MSS status, who have moderate expression of TMB and PD-L1. Additionally, TMB and PD-L1 expression may serve as potential biomarkers for predicting PD-1 inhibitor response of GBC. Furthermore, this needs to be verified in future studies.

Effects of combined chemotherapy and anti-programmed cell death protein 1 treatment on peripheral neuropathy and neuroinflammation in mice

ABSTRACT

A modern approach for cancer treatment is the use of immunotherapy, and particularly immune checkpoint inhibitors, such as anti-programmed cell death protein 1 (PD-1), alone and in combination with chemotherapy. The PD-1 pathway plays a crucial role in inhibiting immune responses and recently has been shown to modulate neuronal activity. However, the impact of PD-1 blockade on the development of chemotherapy-induced peripheral neuropathy is currently unknown. In this study, we show that C57BL/6 mice treated with the chemotherapeutic drug paclitaxel or cotherapy (paclitaxel and anti-PD-1), but not with anti-PD-1 alone, exhibited increased mechanical sensitivity of the hind paw. Both chemotherapy and immunotherapy caused a reduction in neurite outgrowth of dorsal root ganglion (DRG) explants derived from treated mice, whereas only paclitaxel reduced the neurite outgrowth after direct in vitro treatment. Mice treated with anti-PD-1 or cotherapy exhibited distinct T-cell changes in the lymph nodes and increased T-cell infiltration into the DRG. Mice treated with paclitaxel or cotherapy had increased macrophage presence in the DRG, and all treated groups presented an altered expression of microglia markers in the dorsal horn of the spinal cord. We conclude that combining anti-PD-1 immunotherapy with paclitaxel does not increase the severity of paclitaxel-induced peripheral neuropathy. However, because anti-PD-1 treatment caused significant changes in DRG and spinal cord immunity, caution is warranted when considering immune checkpoint inhibitors therapy in patients with a high risk of developing neuropathy.

Immune-checkpoint inhibitors in pituitary malignancies

To date, there are no standardized systemic treatment options for patients with metastatic pituitary carcinoma progressed to chemo and radiation therapy. Immune-checkpoint inhibitors (ICIs) have been successfully assessed in other solid malignancies and could be a concrete hope for these patients. We performed a critical review of the literature aimed to evaluate studies assessing ICIs in pituitary malignancies. We also conducted research about published translational data assessing immune-contexture in these malignancies. Some preliminary reports reported a successful administration of pembrolizumab or the combination between nivolumab and ipilimumab in patients with metastatic ACTH-secreting pituitary carcinomas. Translational data suggest that adenomas secreting growth hormone and ACTH have a suppressed immune-microenvironment, which could be more likely to benefit from ICIs. Immune-checkpoint inhibitors can be an effective treatment in patients with pituitary carcinoma and maybe also recurrent adenoma. Tumors secreting growth hormone and ACTH are more likely to benefit from ICIs due to a different immune-microenvironment.

Clinical and prognostic implications of an immune-related risk model based on TP53 status in lung adenocarcinoma

TP53 mutation is the most widespread mutation in lung adenocarcinoma (LUAD). Meanwhile, p53 (encoded by TP53) has recently been implicated in immune responses. However, it is still unknown whether TP53 mutation remodels the tumour microenvironment to influence tumour progression and prognosis in LUAD. In this study, we developed a 6‐gene immune‐related risk model (IRM) to predict the survival of patients with LUAD in The Cancer Genome Atlas (TCGA) cohort based on TP53 status, and the predictive ability was confirmed in 2 independent cohorts. TP53 mutation led to a decreased immune response in LUAD. Further analysis revealed that patients in the high‐index group had observably lower relative infiltration of memory B cells and regulatory T cells and significantly higher relative infiltration of neutrophils and resting memory CD4⁺ T cells. Additionally, the IRM index positively correlated with the expression of critical immune checkpoint genes, including PDCD1 (encoding PD‐1) and CD274 (encoding PD‐L1), which was validated in the Nanjing cohort. Furthermore, as an independent prognostic factor, the IRM index was used to establish a nomogram for clinical application. In conclusion, this IRM may serve as a powerful prognostic tool to further optimize LUAD immunotherapy.

Anti-Cancer Activity of Phytochemicals Targeting Hypoxia-Inducible Factor-1 Alpha

Hypoxia-inducible factor-1 alpha (HIF-1α) is overexpressed in cancer, leading to a poor prognosis in patients. Diverse cellular factors are able to regulate HIF-1α expression in hypoxia and even in non-hypoxic conditions, affecting its progression and malignant characteristics by regulating the expression of the HIF-1α target genes that are involved in cell survival, angiogenesis, metabolism, therapeutic resistance, et cetera. Numerous studies have exhibited the anti-cancer effect of HIF-1α inhibition itself and the augmentation of anti-cancer treatment efficacy by interfering with HIF-1α-mediated signaling. The anti-cancer effect of plant-derived phytochemicals has been evaluated, and they have been found to possess significant therapeutic potentials against numerous cancer types. A better understanding of phytochemicals is indispensable for establishing advanced strategies for cancer therapy. This article reviews the anti-cancer effect of phytochemicals in connection with HIF-1α regulation.

Advances of Tumorigenesis, Diagnosis at Early Stage, and Cellular Immunotherapy in Gastrointestinal Malignancies

Globally, in 2018, 4.8 million new patients have a diagnosis of gastrointestinal (GI) cancers, while 3.4 million people died of such disorders. GI malignancies are tightly relevant to 26% of the world-wide cancer incidence and occupies 35% of all cancer-associated deaths. In this article, we principally investigated molecular and cellular mechanisms of tumorigenesis in five major GI cancers occurring at esophagus, stomach, liver, pancreas, and colorectal region that illustrate high morbidity in Eastern and Western countries. Moreover, through this investigation, we not only emphasize importance of the tumor microenvironment in development and treatment of malignant tumors but also identify significance of M2PK, miRNAs, ctDNAs, circRNAs, and CTCs in early detection of GI cancers, as well as systematically evaluate contribution of personalized precision medicine including cellular immunotherapy, new antigen and vaccine therapy, and oncolytic virotherapy in treatment of GI cancers.

Strategies to Overcome Failures in T-Cell Immunotherapies by Targeting PI3K-δ and -γ

PI3K-δ and PI3K-γ are critical regulators of T-cell differentiation, senescence, and metabolism. PI3K-δ and PI3K-γ signaling can contribute to T-cell inhibition via intrinsic mechanisms and regulation of suppressor cell populations, including regulatory T-cells and myeloid derived suppressor cells in the tumor. We examine an exciting new role for using selective inhibitors of the PI3K δ- and γ-isoforms as modulators of T-cell phenotype and function in immunotherapy. Herein we review the current literature on the implications of PI3K-δ and -γ inhibition in T-cell biology, discuss existing challenges in adoptive T-cell therapies and checkpoint blockade inhibitors, and highlight ongoing efforts and future directions to incorporate PI3K-δ and PI3K-γ as synergistic T-cell modulators in immunotherapy.

Breast cancer immunotherapy: Current and novel approaches

The crucial role of the immune system in the progression/regression of breast cancer (BC) should always be taken into account. Various immunotherapy approaches have been investigated for BC, including tumor-targeting antibodies (bispecific antibodies), adoptive T cell therapy, vaccines, and immune checkpoint blockade such as anti-PD-1. In addition, a combination of conventional chemotherapy and immunotherapy approaches contributes to improving patients' overall survival rates. Although encouraging outcomes have been reported in most clinical trials of immunotherapy, some obstacles should still be resolved in this regard. Recently, personalized immunotherapy has been proposed as a potential complementary medicine with immunotherapy and chemotherapy for overcoming BC. Accordingly, this review discusses the brief association of these methods and future directions in BC immunotherapy.

Current status of cancer immunotherapy with immune checkpoint inhibitors

The clinical outcome in advanced cancer has improved since the development of targeted therapies and immune checkpoint inhibitors. We can expect better overall survival after a combination treatment with these therapeutic agents. Classical cytotoxic chemotherapeutic agents directly kill tumor cells by destroying the cell structure and DNA of tumor cells or inhibiting their metabolism. Targeted therapy also directly affects tumor cells by inhibiting the cell growth signaling system. Conversely, immune checkpoint inhibitors can enhance immune responses by using the host immune system in the tumor microenvironment, leading to the direct killing of tumor cells. Therefore, immune checkpoint inhibitors are less toxic and have longer response durations. Even in solid tumors with nonimmunogenic backgrounds, cytotoxic chemotherapy or targeted treatment can induce immune responses to place the tumor microenvironment in an immunogenic state. Synergistic anticancer effects can be expected when immune checkpoint inhibitors are added during this state. Moreover, drug resistance may be overcome by combination therapies. If patients with cancer are treated with a combination of these therapeutic agents and the characteristics of each tumor are identified with data from next generation sequencing, personalized treatments can be tailored, making it possible to control cancers as a curable disease just like other benign chronic diseases.

Cell-free DNA copy number variations predict efficacy of immune checkpoint inhibitor-based therapy in hepatobiliary cancers

Background

This study was designed to screen potential biomarkers in plasma cell-free DNA (cfDNA) for predicting the clinical outcome of immune checkpoint inhibitor (ICI)-based therapy in advanced hepatobiliary cancers.

Methods

Three cohorts including 187 patients with hepatobiliary cancers were recruited from clinical trials at the Peking Union Medical College Hospital. Forty-three patients received combination therapy of programmed cell death protein 1 (PD-1) inhibitor with lenvatinib (ICI cohort 1), 108 patients received ICI-based therapy (ICI cohort 2) and 36 patients received non-ICI therapy (non-ICI cohort). The plasma cfDNA and blood cell DNA mutation profiles were assessed to identify efficacy biomarkers by a cancer gene-targeted next-generation sequencing panel.

Results

Based on the copy number variations (CNVs) in plasma cfDNA, the CNV risk score model was constructed to predict survival by using the least absolute shrinkage and selection operator Cox regression methods. The results of the two independent ICI-based therapy cohorts showed that patients with lower CNV risk scores had longer overall survival (OS) and progression-free survival (PFS) than those with high CNV risk scores (log-rank p<0.01). In the non-ICI cohort, the CNV risk score was not associated with PFS or OS. Furthermore, the results indicated that 53% of patients with low CNV risk scores achieved durable clinical benefit; in contrast, 88% of patients with high CNV risk scores could not benefit from combination therapy (p<0.05).

Conclusions

The CNVs in plasma cfDNA could predict the clinical outcome of the combination therapy of PD-1 inhibitor with lenvatinib and other ICI-based therapies in hepatobiliary cancers.

The Efficacy and Safety of Apatinib Plus Camrelizumab in Patients With Previously Treated Advanced Biliary Tract Cancer: A Prospective Clinical Study

Background

PD-1/L1 inhibitor-based immunotherapy is currently under investigation in biliary tract cancer (BTC). Apatinib combined with camrelizumab has achieved promising results in various tumor types. The aim of this study was to assess the safety and efficacy of apatinib plus camrelizumab for advanced biliary tract cancer patients who have received previously treatments.

Methods

This prospective, non-randomized, open-label trial was conducted at Peking Union Medical College Hospital (PUMCH). All included patients received apatinib orally at 250 mg per a day and camrelizumab intravenously at 200 mg every three weeks until disease progression or intolerable toxicity occurred. Efficacy was evaluated based on the Response Evaluation Criteria in Solid Tumors RECIST Version 1.1 (RECIST 1.1). Adverse events (AEs) were assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE version 4.0).

Results

A total of 22 patients were consecutively enrolled from 1st December, 2018 until 1st August, 2020. Among 21 patients for whom we could conduct efficacy evaluations, no patients achieved a complete response (CR), 4 patients (19%) achieved partial response (PR), and 11 patients had stable disease with a disease control rate of 71.4%. The median overall survival was 13.1 months (95% CI, 8.1-18.2), and the median progression-free survival was 4.4 months (95% CI, 2.4-6.3). All patients experienced treatment related AEs, and grade 3 or 4 AEs occurred in 14 (63.6%) of 22 patients. No treatment related deaths were observed.

Conclusions

This is the first report focusing on the efficacy and safety of camrelizumab plus apatinib in pretreated biliary tract cancer patients. The finding suggests this regimen has favorable therapeutic effects with relatively manageable toxicity. Further trials with a control arm are required to investigate.

Clinical Trial Registration

identifier NCT04642664.

Current and Future Perspectives of PD-1/PDL-1 Blockade in Cancer Immunotherapy

Cancer immunotherapy, which reactivates weakened immune cells of cancer patients, has yielded great success in recent years. Among immunotherapeutic agents, immune checkpoint inhibitors have been of particular interest and have gained approval by the FDA for treatment of cancers. Immune checkpoint blockade through targeting programmed cell death protein-1 (PD-1) has demonstrated promising antitumor effects in cancer immunotherapy of many different solid and hematologic malignancies. However, despite promising results, a favorable response is observed only in a fraction of patients, and there is still lack of a single therapy modality with curative ability. In this paper, we review the current and future perspectives of PD-1/L1 blockade in cancer immunotherapy, with a particular focus on predictive biomarkers of response to therapy. We also discuss the adverse events associated with PD-1/L1/2 inhibitors, ranging from severe life-threatening conditions such as autoimmune myocarditis to mild and moderate reactions such as skin rashes, and explore the potential strategies for improving the efficacy of immunotherapy with PD-1/L1 checkpoint inhibitors.

Development of a Metastasis-Related Immune Prognostic Model of Metastatic Colorectal Cancer and Its Usefulness to Immunotherapy

Background: Post-surgical recurrence of the metastatic colorectal cancer (mCRC) remains a challenge, even with adjuvant therapy. Moreover, patients show variable outcomes. Here, we set to identify gene models based on the perspectives of intrinsic cell activities and extrinsic immune microenvironment to predict the recurrence of mCRC and guide the adjuvant therapy.

Methods: An RNA-based gene expression analysis of CRC samples (total = 998, including mCRCs = 344, non-mCRCs = 654) was performed. A metastasis-evaluation model (MEM) for mCRCs was developed using the Cox survival model based on the prognostic differentially expressed genes between mCRCs and non-mCRCs. This model separated the mCRC samples into high- and low-recurrence risk clusters that were tested using machine learning to predict recurrence. Further, an immune prognostic model (IPM) was built using the COX survival model with the prognostic differentially expressed immune-related genes between the two MEM risk clusters. The ability of MEM and IPM to predict prognosis was analyzed and validated. Moreover, the IPM was utilized to evaluate its relationship with the immune microenvironment and response to immuno-/chemotherapy. Finally, the dysregulation cause of IPM three genes was analyzed in bioinformatics.

Results: A high post-operative recurrence risk was observed owing to the downregulation of the immune response, which was influenced by MEM genes (BAMBI, F13A1, LCN2) and their related IPM genes (SLIT2, CDKN2A, CLU). The MEM and IPM were developed and validated through mCRC samples to differentiate between low- and high-recurrence risk in a real-world cohort. The functional enrichment analysis suggested pathways related to immune response and immune system diseases as the major functional pathways related to the IPM genes. The IPM high-risk group (IPM-high) showed higher fractions of regulatory T cells (Tregs) and smaller fractions of resting memory CD4+ T cells than the IPM-low group. Moreover, the stroma and immune cells in the IPM-high samples were scant. Further, the IPM-high group showed downregulation of MHC class II molecules. Additionally, the Tumor Immune Dysfunction and Exclusion (TIDE) algorithm and GDSC analysis suggested the IPM-low as a promising responder to anti-CTLA-4 therapy and the common FDA-targeted drugs, while the IPM-high was non-responsive to these treatments. However, treatment using anti-CDKN2A agents, along with the activation of major histocompatibility complex (MHC) class-II response might sensitize this refractory mCRC subgroup. The dysfunction of MEIS1 might be the reason for the dysregulation of IPM genes.

Conclusions: The IPM could identify subgroups of mCRC with a distinct risk of recurrence and stratify the patients sensitive to immuno-/chemotherapy. Further, for the first time, our study highlights the importance of MHC class-II molecules in the treatment of mCRCs using immunotherapy.

Clinical efficacy of immune checkpoint inhibitors in patients with brain metastases

Brain metastases (BMs) represent a negative prognostic factor for patients with solid malignancies. BMs are generally approached with loco-regional treatments and the blood-brain barrier limits the efficacy of some systemic drugs. The aim of this review is to summarize current knowledge about the role of immune checkpoint inhibitors for the management of brain metastases in patients with solid malignancies. We performed a review of available literature. Immune checkpoint inhibitors represent the standard treatment for several advanced solid malignancies. However, with the exception of melanoma their clinical role in other solid malignancies is not completely clear due to the exclusion of patients with BM from approval clinical trials. Immune-checkpoint inhibitors may be an effective treatment of brain metastases of melanoma while their clinical role on brain metastases from other solid malignancies is uncertain.

Distinctive genomic characteristics in POLE/POLD1-mutant cancers can potentially predict beneficial clinical outcomes in patients who receive immune checkpoint inhibitor

Background

Mutations in POLE /POLD1 proofreading domain can cause deficiencies in DNA repair, conferring ultramutated cancer phenotypes. Preliminary clinical studies have revealed an association between POLE/POLD1 mutations and beneficial clinical outcomes to immune checkpoint inhibitor (ICI) therapy This study aims to investigate the genomic characteristics of POLE/POLD-mutant tumors and the prognostic value of POLE/POLD mutation for ICI treatment.

Methods

Genomic data of 21,074 patients with 23 cancer types were retrieved from Burning Rock variant database (BR VarDB). The prevalence and spectra of POLE and POLD1 mutations were assessed and compared with that in The Cancer Genome Atlas (TCGA) samples. The correlations of POLE/POLD1 mutation with tumor mutational burden (TMB) and microsatellite instability (MSI) were investigated. The prognostic value of POLE/POLD1 mutations was also explored in 2,487 ICI-treated patients from published studies.

Results

BR VarDB samples displayed a similar mutational prevalence of POLE (3.2% vs. 3.2%) and POLD1 (1.4% vs. 1.6%, P=0.248) versusTCGA samples, but a slightly lower frequency of POLE and POLD1 co-mutations (0.21% vs. 0.43%, P<0.001). POLE/POLD1-mutant tumors harbored increased TCT→TAT and TCG→TTG transversions, and genomic signatures associated with DNA mismatch repair (MMR) deficiency and ultra-hypermuation. Furthermore, tumors with POLE/POLD1 proofreading mutation showed a significantly higher TMB than tumors with non-proofreading mutations (P<0.01), although both possessed a higher TMB than POLE/POLD1 wild-type (WT) tumors (P<0.0001 and P<0.0001, respectively). MSI was commonly observed in tumors harboring dominant clone of POLE/POLD1 mutation (10.2%), but occurred rarely in POLE/POLD1 WT tumors (0.5%) and tumors with accumulating sub-cloned POLE/POLD1 mutation (0%). Survival analysis revealed that POLE/POLD1 mutation was not independently correlated with longer survival after adjusting for TMB and other factors (HR =0.86, P=0.372). However, patients harboring POLE/POLD1 mutation demonstrated a higher response rate than patients with POLE/ POLD1 WT tumors (35.2% vs. 19.6%, P=0.0165).

Conclusions

We delineated distinctive genomic characteristics in POLE/POLD1-mutant tumors, suggesting the potential predictive role of POLE/POLD1 mutations, especially those in the proofreading domain, for beneficial outcomes of immunotherapy. Our results also suggest that MSI caused by a loss-of-function mutation in the MMR pathway tends to result from POLE/POLD1 proofreading deficiency in POLE/POLD1-mutant tumors with MSI.

Intrahepatic cholangiocarcinoma: Morpho-molecular pathology, tumor reactive microenvironment, and malignant progression

Intrahepatic cholangiocarcinoma (iCCA) is a relatively rare, but highly lethal and biologically complex primary biliary epithelial cancer arising within liver. After hepatocellular carcinoma, iCCA is the second most common primary liver cancer, accounting for approximately 10-20% of all primary hepatic malignancies. Over the last 10-20 years, iCCA has become the focus of increasing concern largely due to its rising incidence and high mortality rates in various parts of the world, including the United States. The challenges posed by iCCA are daunting and despite recent progress in the standard of care and management options for iCCA, the prognosis for this cancer continues to be dismal. In an effort to provide a framework for advancing our understanding of iCCA malignant aggressiveness and therapy resistance, this review will highlight key etiological, biological, molecular, and microenvironmental factors hindering more effective management of this hepatobiliary cancer. Particular focus will be on critically reviewing the cell origins and morpho-molecular heterogeneity of iCCAs, providing mechanistic insights into high risk fibroinflammatory cholangiopathies associated with iCCA development, and notably discussing the deleterious role played by the tumor reactive desmoplastic stroma in regulating iCCA malignant progression, lymphangiogenesis, and tumor immunobiology.

RNA sequencing: new technologies and applications in cancer research

Over the past few decades, RNA sequencing has significantly progressed, becoming a paramount approach for transcriptome profiling. The revolution from bulk RNA sequencing to single-molecular, single-cell and spatial transcriptome approaches has enabled increasingly accurate, individual cell resolution incorporated with spatial information. Cancer, a major malignant and heterogeneous lethal disease, remains an enormous challenge in medical research and clinical treatment. As a vital tool, RNA sequencing has been utilized in many aspects of cancer research and therapy, including biomarker discovery and characterization of cancer heterogeneity and evolution, drug resistance, cancer immune microenvironment and immunotherapy, cancer neoantigens and so on. In this review, the latest studies on RNA sequencing technology and their applications in cancer are summarized, and future challenges and opportunities for RNA sequencing technology in cancer applications are discussed.

The Extrinsic and Intrinsic Roles of PD-L1 and Its Receptor PD-1: Implications for Immunotherapy Treatment

Programmed death-ligand 1 (PD-L1) is an immune checkpoint inhibitor that binds to its receptor PD-1 expressed by T cells and other immune cells to regulate immune responses; ultimately preventing exacerbated activation and autoimmunity. Many tumors exploit this mechanism by overexpressing PD-L1 which often correlates with poor prognosis. Some tumors have also recently been shown to express PD-1. On tumors, PD-L1 binding to PD-1 on immune cells promotes immune evasion and tumor progression, primarily by inhibition of cytotoxic T lymphocyte effector function. PD-1/PD-L1-targeted therapy has revolutionized the cancer therapy landscape and has become the first-line treatment for some cancers, due to their ability to promote durable anti-tumor immune responses in select patients with advanced cancers. Despite this clinical success, some patients have shown to be unresponsive, hyperprogressive or develop resistance to PD-1/PD-L1-targeted therapy. The exact mechanisms for this are still unclear. This review will discuss the current status of PD-1/PD-L1-targeted therapy, oncogenic expression of PD-L1, the new and emerging tumor-intrinisic roles of PD-L1 and its receptor PD-1 and how they may contribute to tumor progression and immunotherapy responses as shown in different oncology models.

Phase I, first-in-human trial of programmed cell death receptor-1 (PD-1) inhibitor, JTX-4014, in adult patients with advanced, refractory, solid tumors

Background

Inhibition of programmed cell death receptor protein-1 (PD-1) has proven to be a highly effective strategy for immunotherapy of cancer. Approvals of both PD-1 and PD-L1 inhibitors [PD-(L)1i] in multiple tumor types are evidence of the durable benefits they provide to patients with cancer. In this first-in-human trial, we assessed the safety and tolerability of JTX-4014, a fully human antibody targeting PD-1.

Methods

JTX-4014 was administered to 18 patients with multiple solid tumor types who had not previously received a PD-(L)1i. The primary objectives were to evaluate the safety and tolerability of JTX-4014 and determine the maximum tolerated dose (MTD) and recommended phase II dose (RP2D). Secondary objectives included evaluation of the pharmacokinetics (PK) of JTX-4014, anti-drug antibodies (ADA) against JTX-4014, and clinical activity.

Results

JTX-4014 was well tolerated and no new safety signals were identified as compared with other PD-1is. The MTD was not reached and the RP2D was selected, based on PK modelling and supportive safety data, to be 500 mg every 3 weeks or 1000 mg every 6 weeks. Clinical activity, based on RECIST v1.1 criteria, demonstrated an overall response rate of 16.7% (n = 3) with one complete and two partial responses and a disease control rate of 44.4% (n = 8). The responses occurred at different doses in patients with PD-L1 positive tumors and in tumor types that are not typically PD-1i responsive.

Conclusions

Further development of JTX-4014 is warranted as a monotherapy or in combination with other innovative cancer therapies.

Trial registration number

NCT03790488, December 31 2018.

TRPM8 facilitates proliferation and immune evasion of esophageal cancer cells

Esophageal cancer is seen with increasing incidence, but the underlying mechanism of esophageal cancer is still unknown. Transient receptor potential melastatin (TRPM) is non-selective cation channels. It has been verified that TRPM channels play crucial roles in development and progression of multiple tumors. Increasing studies have shown that TRPM8, a member of TRPM channels, promotes growth of tumors. However, it is still unclear whether TRPM8 has biological effect on esophageal cancer. In the current work, we found that TRPM8 was overexpressed in esophageal cancer samples and cell lines. Further investigation revealed that TRPM8 promoted proliferation of esophageal cancer cells. Next, the co-incubation assay including EC109 cells and CD8⁺ T cells revealed that TRPM8 overexpression and TRPM8 agonist reduced the cytotoxic effect of CD8⁺ T cell on esophageal cancer cells. Finally, we explored the mechanism and found that calcineurin-nuclear factor of activated T cells 3 (NFATc3) pathway contributed to the expression of programmed death ligand 1 (PD-L1) induced by TRPM8 overexpression and TRPM8 agonist, which might lead to immune evasion of esophageal cancer cells. These findings uncovered the crucial role of TRPM8 in the pathogenesis of esophageal cancer.

YTHDF2 correlates with tumor immune infiltrates in lower-grade glioma

Immunotherapy is an effective treatment for many cancer types. However, YTHDF2 effects on the prognosis of different tumors and correlation with tumor immune infiltration are unclear. Here, we analyzed The Cancer Genome Atlas and Gene Expression Omnibus data obtained through various web-based platforms. The analyses showed that YTHDF2 expression and associated prognoses may depend on cancer type. High YTHDF2 expression was associated with poor overall survival in lower-grade glioma (LGG). In addition, YTHDF2 expression positively correlated with expression of several immune cell markers, including PD-1, TIM-3, and CTLA-4, as well as tumor-associated macrophage gene markers, and isocitrate dehydrogenase 1 in LGG. These findings suggest that YTHDF2 is a potential prognostic biomarker that correlates with LGG tumor-infiltrating immune cells.

The Latest Findings of PD-1/PD-L1 Inhibitor Application in Gynecologic Cancers

Gynecologic cancers account for approximately 11% of the newly diagnosed cancers in women in the United States and for 18% globally. The presence of tumor-infiltrating lymphocytes (TILs) influences the clinical outcome of cancer patients and immune checkpoint inhibitors (ICIs), including anti programmed cell death protein-1 (anti-PD-1), anti-programmed death-ligand 1 (anti-PD-L1), and anticytotoxic T-lymphocyte antigen 4 (anti-CTLA-4), which have been approved for treating different types of malignancies. Antibodies targeting the PD-1/PD-L1 checkpoint have shown dynamic and durable tumor regressions, suggesting a rebalancing of the host-tumor interaction. There are several the US food and drug administration (FDA)-approved ICIs targeting PD-1, including pembrolizumab and nivolumab, as well as those targeting PD-L1, including avelumab, atezolizumab, and durvalumab for melanoma, renal cell cancer, colorectal cancer, head and neck cancer, cervix cancer, urothelial cancer, and lung cancer. Current pre-clinical and clinical studies assessing PD-1/PD-L1 inhibitors in several gynecologic cancers have reported significant antitumor activity. In this review, we investigate pre-clinical and clinical studies that describe the safety and efficacy of anti-PD-1/PD-L1 antibodies, with a particular focus on ongoing clinical trials, analyzing the oncological outcome and adverse effects of ICIs in gynecologic cancers.

Comparing the efficacy and safety of second-line therapies for advanced hepatocellular carcinoma: a network meta-analysis of phase III trials

BACKGROUND

The prospect for targeted therapies in advanced hepatocellular carcinoma (HCC) has dramatically changed since several recent clinical trials have yielded promising results. The number of second-line therapies is increasing, though the consequent challenge is to consider differences between these interventions. This is a comparative investigation of presently approved second-line drugs for HCC based on findings from phase III randomized controlled trials.

METHODS

Data related to treatment efficacy including overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were extracted and compared using a Bayesian approach. Adverse events (AEs) and the rate of discontinuation due to AEs were assessed and compared with provide a more complete understanding. OS and PFS in patients with alpha fetoprotein (AFP) values greater than 400 were compared and ranked as a subgroup.

RESULTS

A total of five trials involving 2571 patients were included. The comparison suggests that regorafenib and cabozantinib significantly prolong OS compared with placebo. The rate of AEs and treatment discontinuation did not significantly differ, although the types of AEs varied substantially. Subgroup analysis did not highlight a significant OS difference between regorafenib [hazard ratio (HR) 0.68; 95% confidence interval (CI) 0.50-0.92], cabozantinib (HR 0.71; CI 0.54-0.94) and ramucirumab (HR 0.69; CI 0.57-0.84). Conclusion: Among the four second-line HCC therapies compared, regorafenib and cabozantinib appear to be better choices in terms of OS. Cabozantinib, regorafenib and ramucirumab have similar levels of efficacy for those with AFP >400, although ramucirumab has fewer side effects. No significant difference was observed in AEs, but some AEs related to each of these interventions should be given further consideration.

Trial watch: IDO inhibitors in cancer therapy

Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first, rate-limiting step of the so-called “kynurenine pathway”, which converts the essential amino acid L-tryptophan (Trp) into the immunosuppressive metabolite L-kynurenine (Kyn). While expressed constitutively by some tissues, IDO1 can also be induced in specific subsets of antigen-presenting cells that ultimately favor the establishment of immune tolerance to tumor antigens. At least in part, the immunomodulatory functions of IDO1 can be explained by depletion of Trp and accumulation of Kyn and its derivatives. In animal tumor models, genetic or pharmacological IDO1 inhibition can cause the (re)activation of anticancer immune responses. Similarly, neoplasms expressing high levels of IDO1 may elude anticancer immunosurveillance. Therefore, IDO1 inhibitors represent promising therapeutic candidates for cancer therapy, and some of them have already entered clinical evaluation. Here, we summarize preclinical and clinical studies testing IDO1-targeting interventions for oncologic indications.

Chimeric antigen receptor T cells targeting PD-L1 suppress tumor growth

Background

Chimeric antigen receptor T cells (CAR-T cells) therapy has been well recognized for treating B cell-derived malignancy. However, the efficacy of CAR-T cells against solid tumors remains dissatisfactory, partially due to the heterogeneity of solid tumors and T cell exhaustion in tumor microenvironment. PD-L1 is up-regulated in multiple solid tumors, resulting in T cell exhaustion upon binding to its receptor PD-1.

Methods

Here, we designed a dominant-negative form of PD-1, dPD1z, a vector containing the extracellular and transmembrane regions of human PD-1, and a CAR vector against PD-L1, CARPD-L1z, a vector employs a high-affinity single-chain variable fragment (scFv) against human PD-L1. These two vectors shared the same intracellular structure, including 4-1BB and TLR2 co-stimulatory domains, and the CD3ζ signaling domain.

Results

dPD1z T and CARPD-L1z T cells efficiently lysed PD-L1⁺ tumor cells and had enhanced cytokine secretion in vitro and suppressed the growth of non-small cell lung cancer (NSCLC), gastric cancer and hepatoma carcinoma in patient-derived xenograft (PDX). However, the combination of anti-mesothelin CAR-T cells (CARMSLNz T) with dPD1z T or CARPD-L1z T cells did not repress tumor growth synergistically in PDX, as CARMSLNz T cells upregulated PD-L1 expression upon activation and were subsequently attacked by dPD1z T or CARPD-L1z T cells.

Conclusions

In conclusion, we demonstrate CAR-T cells targeting PD-L1 were effective for suppressing the growth of multiple types of solid tumors in PDX models though their safety needs to be carefully examined.

Regulation of PD-1 in T cells for cancer immunotherapy

Study of the molecular mechanisms underlying cancer immune escape is one of the core issues in immuno-oncology research. Cancer cells can evade T cell cytotoxicity by exploiting the upregulation of T cell inhibitory receptors on T cells and their ligands on cancer cells. These upregulated proteins include the inhibitory receptor programmed cell-death protein 1 (PD-1) and its ligand programmed cell death 1 ligand 1 (PD-L1), which can induce T cell exhaustion and reduce T cell activation. Characterizing PD-1 regulation will help to elucidate the molecular mechanisms underlying T cell exhaustion and improve cancer treatment. Recent studies have found that tumor cells regulate PD-1 during gene transcription, post-transcriptional regulation, and post-translational modification and influence the effects of the anticancer immune response by targeting PD-1. In this review,we summarize the mechanisms of PD-1 regulation in T cells.

The role of cancer-derived microRNAs in cancer immune escape

During malignant transformation, accumulated somatic mutations endow cancer cells with increased invasiveness and immunogenicity. Under selective pressure, these highly immunogenic cancer cells develop multiple strategies to evade immune attack. It has been well established that cancer cells could downregulate the expression of major histocompatibility complex, acquire alterations in interferon pathway, and upregulate the activities of immune checkpoint pathways. Besides, cancer cells secret numerous cytokines, exosomes, and microvesicles to regulate the functions and abundances of components in the tumor microenvironment including immune effector cells and professional antigen presentation cells. As the vital determinant of post-transcriptional regulation, microRNAs (miRNAs) not only participate in cancer initiation and progression but also regulate anti-cancer immune response. For instance, some miRNAs affect cancer immune surveillance and immune escape by interfering the expression of immune attack-associated molecules. A growing body of evidence indicated that cancer-derived immune modulatory miRNAs might be promising targets to counteract cancer immune escape. In this review, we summarized the role of some miRNAs in cancer immune escape and discussed their potential clinical application as treatment targets.