The bispecific anti-CD3 × anti-CD155 antibody mediates T cell immunotherapy for human prostate cancer

Bispecific antibody targeting CD155 mediates T-cell immunotherapy against human gynecological malignancies

T cells are crucial regulators in cancer treatment due to their cytotoxic ability. Recently, immunotherapies based on bispecific antibodies (Bi-Ab) have achieved remarkable effects in cancer treatment, attributed to their capability of recruiting and activating T cells to kill tumors. In the present study, we investigated whether CD155 is an effective target for T-cell-mediated immunotherapy against human gynecological malignancies. We demonstrated that CD155 is expressed on common gynecological tumor cells, including cervical, uterine, and ovarian cancers. Next, we evaluated the specific cytotoxic activity of T cells armed with CD155Bi-Ab (CD155Bi-T cells) against tumor cells. Compared with control T cells treated with separate anti-CD155 and anti-CD3 mAbs, CD155Bi-T cells exhibited significant cytotoxicity against CD155-positive gynecological tumor cells. Specifically, in the luciferase assay, the cytotoxicity of CD155Bi-T cells was 2.67-fold higher than that of control T cells at an effector/target ratio of 5:1, indicating a significant enhancement in tumor-killing activity. This enhanced cytotoxic activity was further supported by increased expression of activation markers (CD69 and 4 - 1BB), higher production of T-cell-derived cytokines (IL- 2, IFN-γ, and TNF-α), and elevated levels of the cell-killing mediators (perforin and granzyme B). Taken together, our findings demonstrate that CD155 is a promising target for gynecological tumors, and CD155Bi-T cells hold significant potential for immunotherapy against CD155+ gynecological malignancies.

LBP-CD155 Liposome Nanovaccine Efficiently Resist Colorectal Cancer and Enhance ICB Therapy

Background

Colorectal cancer (CRC) is a highly malignant and aggressive gastrointestinal tumor. Due to its weak immunogenicity and limited immune, cell infiltration lead to ineffective clinical outcomes. Therefore, to improve the current prophylaxis and treatment scheme, offering a favorable strategy efficient against CRC is urgently needed.

Methods

Here, we developed a nanovaccine (LBP-CD155L NVs) loaded with CD155 gene in liposome, which was modified by Lycium barbarum polysaccharides (LBP) through electrostatic interaction. The nanovaccine was characterized by transmission electron microscopy and Zetasizer. It was evaluated in vitro, where NVs facilitated the endocytosis and maturation of DCs, and in vivo, where NVs improved the efficacy of prophylaxis and therapy. In addition, further confirmed the mechanisms by how TLR4 and MGL synergistic pathway endow the nanovaccines towards dendritic cells (DCs). Finally, the safety and tumor immunosuppressive microenvironment were evaluated in the CRC tumor-bearing mouse model.

Results

We successfully developed a nanovaccine that facilitates the endocytosis and maturation of DCs via a synergistic pathway involving TLR4 and MGL, which endow the nanovaccines towards dendritic cells (DCs) and promote the differentiation, thereby enhancing the cytotoxicity of CD8+T cells. Consequently, LBP-CD155L NVs can potentiate the efficacy of prophylactic and therapeutic administration in a mouse CRC model, as evidenced by decreased infiltration of myeloid-derived suppressor cells (MDSCs) and Tregs, reprogrammed the macrophage phenotypes, which promoted polarization from M2-like macrophages to M1-like macrophages, increased infiltration of effector T cells. Prophylactic and therapeutic combination regimens with anti-PD-1 treatment demonstrate synergism that stimulates T-cell infiltration into tumors and counteracts immunosuppression, leading to remarkable tumor remission and enhancing the efficacy of immune checkpoint therapy in solid tumors.

Conclusion

Our work provided that LBP-CD155L NVs may serve as a promising tool for reversing tumor immunosuppressive microenvironment and enhancing ICB therapy in CRC.

Bispecific anti-CD3×anti-CD155 antibody mediates T-cell immunotherapy in human haematologic malignancies

T cells are important components in the cell-mediated antitumour response. In recent years, bispecific antibodies (Bi-Abs) have become promising treatments because of their ability to recruit T cells that kill tumours. Here, we demonstrate that CD155 is expressed in a wide range of human haematologic tumours and report on the ability of the bispecific antibody anti-CD3 x anti-CD155 (CD155Bi-Ab) to activate T cells targeting malignant haematologic cells. The specific cytolytic effect of T cells armed with CD155Bi-Ab was evaluated by quantitative luciferase assay, and the results showed that the cytolytic effect of these cells was accompanied by an increase in the level of the cell-killing mediator perforin. Moreover, compared with their unarmed T-cell counterparts, CD155Bi-Ab-armed T cells induced significant cytotoxicity in CD155-positive haematologic tumour cells, as indicated by lactate dehydrogenase assays, and these results were accompanied by increased granzyme B secretion. Furthermore, CD155Bi-Ab-armed T cells produced more T-cell-derived cytokines, including TNF-α, IFN-γ, and IL-2. In conclusion, CD155Bi-Ab enhances the ability of T cells to kill haematologic tumour cells, and therefore, CD155 may serve as a novel target for immunotherapy against haematologic malignancies.

Recent advances in the molecular targeted drugs for prostate cancer

CONTEXT

Prostate cancer (PCa) is the second largest male tumor in the world and one of the most common malignant tumors in the urinary system. In recent years, the incidence rate of PCa in China has been increasing year by year. Meanwhile, refractory hormone resistance and adverse drug reactions of advanced PCa cause serious harm to patients.

OBJECTIVE

The present study aims to systematically review the recent advances in molecularly targeted drugs for prostate cancer and to use the retrieval and analysis of the literature library to summarize the adverse effects of different drugs so as to maximize the treatment benefits of targeted therapies.

EVIDENCE ACQUISITION

We performed a systematic literature search of the Medline, EMBASE, PubMed, and Cochrane databases up to March 2022 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Medical Subject Heading (MeSH) terms and keywords such as (prostate cancer) AND (molecular target drugs) AND (side effect) were used. No language restrictions were set on the search process, and all these results were processed independently by two authors. Consensus was reached through discussion once met with any disagreements. The primary endpoint was differential features between different molecular targeted drugs. Secondary endpoints were side effects of different drugs on the body and corresponding prognostic values.

EVIDENCE SYNTHESIS

The Cochrane Collaboration risk of bias tool was used to assess the study quality in terms of sequence generation, allocation concealment, blinding, the completeness of outcome data, selective reporting and other biases. We retrieved 332 articles, of which 49 met the criteria for inclusion. Included studies show that prostatic tumor cells, tumor neovascularization and immune checkpoints are the main means for targeted therapy. Common drugs include 177 Lu-PSMA, Olaparib, Rucaparib, Bevacizumab, Pazopanib, Sorafenib, Cabozantinib, Aflibercept, Ipilimumab, Atezolizumab, Avelumab, Durvalumab. A series of publicly available data suitable for further analysis of side effects. An over-representation analysis of these datasets revealed reasonable dosage and usage is the key to controlling the side effects of targeted drugs. Important information such as the publication year, the first author, location and outcome observation of adverse effects was extracted from the original article. If the study data has some insufficient data, contacting the corresponding authors is necessary. All the studies included prospective nonrandomized and randomized research. Retrospective reviews were also screened according to the relevant to the purpose of this study. Meeting abstracts as well as letters to the editor and editorials were excluded.

STATISTICAL ANALYSIS

Data analysis was based on Cochrane's risk of bias tools to obtain the quality assessment. The included randomized studies used RoB2 and non-randomized ones corresponded to ROBINS-I. Standardized mean differences (SMD) were used to determine relative risk (RR) and side effects between groups. The eggers' test was used to check the publication bias from variable information in the included studies. All p < 0.05 were considered to be significant, and 95% was set as the confidence interval.

CONCLUSIONS

With the approval of a variety of targeted drugs, targeted therapy will be widely used in the treatment of advanced or metastatic prostate cancer. Despite the existence of adverse reactions related to targeted drug treatment, it is still meaningful to adjust the drug dosage or treatment cycle to reduce the occurrence of adverse reactions, improving the treatment benefits of patients.

Expression of Membranous CD155 Is Associated with Aggressive Phenotypes and a Poor Prognosis in Patients with Bladder Cancer

Objective: To investigate the relationship between clinicopathological findings and membranous CD155 (mCD155) or cytoplasmic CD155 (cCD155) expression in bladder cancer (BC). Methods: We retrospectively analyzed 103 patients with BC who underwent radical cystectomy between 1990 to 2015 at Kitasato University Hospital. Immunohistochemical staining was performed to evaluate CD155 expression in tumor cells. Cases with > 10% expression on the membrane or cytoplasm of tumor cells were positive. The Fisher′s exact test was used for categorical variables and the Kaplan−Meier method was used for survival outcomes. Univariate and multivariate Cox regression hazard models were used to evaluate the survival risk factors. Results: Cases that were mCD155-positive were associated with high-grade tumors (p = 0.02), nodal status (p < 0.01), and pT stage (p = 0.04). No association with any clinicopathological factor was observed in the cCD155 cases. Kaplan−Meier analysis showed that mCD155-positive cases had shorter periods of recurrence-free survival (p = 0.015) and cancer-specific survival (p = 0.005). Only nodal status was an independent predictor for both cancer-specific survival and recurrence-free survival in multivariate analysis (p = 0.02 and p < 0.01, respectively). Conclusion: mCD155 expression may be a marker of an aggressive phenotype and a poor prognosis in patients with BC.

Interaction Between Modern Radiotherapy and Immunotherapy for Metastatic Prostate Cancer

Prostate cancer is the most frequently diagnosed cancer in men and a leading cause of cancer-related death. In recent decades, the development of immunotherapies has resulted in great promise to cure metastatic disease. However, prostate cancer has failed to show any significant response, presumably due to its immunosuppressive microenvironment. There is therefore growing interest in combining immunotherapy with other therapies able to relieve the immunosuppressive microenvironment. Radiation therapy remains the mainstay treatment for prostate cancer patients, is known to exhibit immunomodulatory effects, depending on the dose, and is a potent inducer of immunogenic tumor cell death. Optimal doses of radiotherapy are thus expected to unleash the full potential of immunotherapy, improving primary target destruction with further hope of inducing immune-cell-mediated elimination of metastases at distance from the irradiated site. In this review, we summarize the current knowledge on both the tumor immune microenvironment in prostate cancer and the effects of radiotherapy on it, as well as on the use of immunotherapy. In addition, we discuss the utility to combine immunotherapy and radiotherapy to treat oligometastatic metastatic prostate cancer.

Clinical Research on the Mechanisms Underlying Immune Checkpoints and Tumor Metastasis

This study highlights aspects of the latest clinical research conducted on the relationship between immune checkpoints and tumor metastasis. The overview of each immune checkpoint is divided into the following three sections: 1) structure and expression; 2) immune mechanism related to tumor metastasis; and 3) clinical research related to tumor metastasis. This review expands on the immunological mechanisms of 17 immune checkpoints, including TIM-3, CD47, and OX-40L, that mediate tumor metastasis; evidence shows that most of these immune checkpoints are expressed on the surface of T cells, which mainly exert immunomodulatory effects. Additionally, we have summarized the roles of these immune checkpoints in the diagnosis and treatment of metastatic tumors, as these checkpoints are considered common predictors of metastasis in various cancers such as prostate cancer, non-Hodgkin lymphoma, and melanoma. Moreover, certain immune checkpoints can be used in synergy with PD-1 and CTLA-4, along with the implementation of combination therapies such as LIGHT-VTR and anti-PD-1 antibodies. Presently, most monoclonal antibodies generated against immune checkpoints are under investigation as part of ongoing preclinical or clinical trials conducted to evaluate their efficacy and safety to establish a better combination treatment strategy; however, no significant progress has been made regarding monoclonal antibody targeting of CD28, VISTA, or VTCN1. The application of immune checkpoint inhibitors in early stage tumors to prevent tumor metastasis warrants further evidence; the immune-related adverse events should be considered before combination therapy. This review aims to elucidate the mechanisms of immune checkpoint and the clinical progress on their use in metastatic tumors reported over the last 5 years, which may provide insights into the development of novel therapeutic strategies that will assist with the utilization of various immune checkpoint inhibitors.

Depleting Tumor Cells Expressing Immune Checkpoint Ligands-A New Approach to Combat Cancer

Antibodies against inhibitory immune checkpoint molecules (ICPMs), referred to as immune checkpoint inhibitors (ICIs), have gained a prominent place in cancer therapy. Several ICIs in clinical use have been engineered to be devoid of effector functions because of the fear that ICIs with preserved effector functions could deplete immune cells, thereby curtailing antitumor immune responses. ICPM ligands (ICPMLs), however, are often overexpressed on a sizeable fraction of tumor cells of many tumor types and these tumor cells display an aggressive phenotype with changes typical of tumor cells undergoing an epithelial-mesenchymal transition. Moreover, immune cells expressing ICPMLs are often endowed with immunosuppressive or immune-deviated functionalities. Taken together, these observations suggest that compounds with the potential of depleting cells expressing ICPMLs may become useful tools for tumor therapy. In this article, we summarize the current state of the art of these compounds, including avelumab, which is the only ICI targeting an ICPML with preserved effector functions that has gained approval so far. We also discuss approaches allowing to obtain compounds with enhanced tumor cell-depleting potential compared to native antibodies. Eventually, we propose treatment protocols that may be applied in order to optimize the therapeutic efficacy of compounds that deplete cells expressing ICPMLs.

Bispecific Antibodies in Prostate Cancer Therapy: Current Status and Perspectives

Prostate carcinoma (PC) is the second most common cancer in men. When the disease becomes unresponsive to androgen deprivation therapy, the remaining treatment options are of limited benefit. Despite intense efforts, none of the T cell-based immunotherapeutic strategies that meanwhile have become a cornerstone for treatment of other malignancies is established in PC. This refers to immune checkpoint inhibition (CI), which generally reinforces T cell immunity as well as chimeric antigen receptor T (CAR-T) cells and bispecific antibodies (bsAbs) that stimulate the T cell receptor/CD3-complex and mobilize T cells in a targeted manner. In general, compared to CAR-T cells, bsAb would have the advantage of being an "off the shelf" reagent associated with less preparative effort, but at present, despite enormous efforts, neither CAR-T cells nor bsAbs are successful in solid tumors. Here, we focus on the various bispecific constructs that are presently in development for treatment of PC, and discuss underlying concepts and the state of clinical evaluation as well as future perspectives.

Overcoming Challenges for CD3-Bispecific Antibody Therapy in Solid Tumors

Immunotherapy of cancer with CD3-bispecific antibodies is an approved therapeutic option for some hematological malignancies and is under clinical investigation for solid cancers. However, the treatment of solid tumors faces more pronounced hurdles, such as increased on-target off-tumor toxicities, sparse T-cell infiltration and impaired T-cell quality due to the presence of an immunosuppressive tumor microenvironment, which affect the safety and limit efficacy of CD3-bispecific antibody therapy. In this review, we provide a brief status update of the CD3-bispecific antibody therapy field and identify intrinsic hurdles in solid cancers. Furthermore, we describe potential combinatorial approaches to overcome these challenges in order to generate selective and more effective responses.

Immunotherapy as a Precision Medicine Tool for the Treatment of Prostate Cancer

Prostate cancer (PCa) is the most frequently diagnosed type of cancer among Caucasian males over the age of 60 and is characterized by remarkable heterogeneity and clinical behavior, ranging from decades of indolence to highly lethal disease. Despite the significant progress in PCa systemic therapy, therapeutic response is usually transient, and invasive disease is associated with high mortality rates. Immunotherapy has emerged as an efficacious and non-toxic treatment alternative that perfectly fits the rationale of precision medicine, as it aims to treat patients on the basis of patient-specific, immune-targeted molecular traits, so as to achieve the maximum clinical benefit. Antibodies acting as immune checkpoint inhibitors and vaccines entailing tumor-specific antigens seem to be the most promising immunotherapeutic strategies in offering a significant survival advantage. Even though patients with localized disease and favorable prognostic characteristics seem to be the ones that markedly benefit from such interventions, there is substantial evidence to suggest that the survival benefit may also be extended to patients with more advanced disease. The identification of biomarkers that can be immunologically targeted in patients with disease progression is potentially amenable in this process and in achieving significant advances in the decision for precision treatment of PCa.