Role of vaccine therapy for renal cell carcinoma in the era of targeted therapy

Current Progress in the Science of Novel Adjuvant Nano-Vaccine-Induced Protective Immune Responses

Vaccinations are vital as they protect us from various illness-causing agents. Despite all the advancements in vaccine-related research, developing improved and safer vaccines against devastating infectious diseases including Ebola, tuberculosis and acquired immune deficiency syndrome (AIDS) remains a significant challenge. In addition, some of the current human vaccines can cause adverse reactions in some individuals, which limits their use for massive vaccination program. Therefore, it is necessary to design optimal vaccine candidates that can elicit appropriate immune responses but do not induce side effects. Subunit vaccines are relatively safe for the vaccination of humans, but they are unable to trigger an optimal protective immune response without an adjuvant. Although different types of adjuvants have been used for the formulation of vaccines to fight pathogens that have high antigenic diversity, due to the toxicity and safety issues associated with human-specific adjuvants, there are only a few adjuvants that have been approved for the formulation of human vaccines. Recently, nanoparticles (NPs) have gain specific attention and are commonly used as adjuvants for vaccine development as well as for drug delivery due to their excellent immune modulation properties. This review will focus on the current state of adjuvants in vaccine development, the mechanisms of human-compatible adjuvants and future research directions. We hope this review will provide valuable information to discovery novel adjuvants and drug delivery systems for developing novel vaccines and treatments.

Vaccination against Cancer or Infectious Agents during Checkpoint Inhibitor Therapy

The use of immune checkpoint inhibitors (ICI) has substantially increased the overall survival of cancer patients and has revolutionized the therapeutic situation in oncology. However, not all patients and cancer types respond to ICI, or become resistant over time. Combining ICIs with therapeutic cancer vaccines is a promising option as vaccination may help to overcome resistance to immunotherapies while immunotherapies may increase immune responses to the particular cancer vaccine by reinvigorating exhausted T cells. Thus, it would be possible to reprogram a response with appropriate vaccines, using a particular cancer antigen and a corresponding ICI. Target populations include currently untreatable cancer patients or those who receive treatment regimens with high risk of serious side effects. In addition, with the increased use of ICI in clinical practice, questions arise regarding safety and efficacy of administration of conventional vaccines, such as influenza or COVID-19 vaccines, during active ICI treatment. This review discusses the main principles of prophylactic and therapeutic cancer vaccines, the potential impact on combining therapeutic cancer vaccines with ICI, and briefly summarizes the current knowledge of safety and effectiveness of influenza and COVID-19 vaccines in ICI-treated patients.

New treatment modalities with vaccine therapy in renal cell carcinoma

The aim of implementing vaccine therapy is to activate immune response against malignant cells by overcoming the tolerance triggered by the tumor. These treatments are effective using the immune response against cancer. Not every type of cancer is suitable for vaccine therapies. For a vaccine therapy to be implemented, cancer should be immunogenic and contain tissue-specific proteins, should have a slow progression, and treatments should be feasible. For that reason, studies regarding urological cancers are mostly focused on the kidneys and the prostate. Vaccine therapies used in renal cell carcinoma (RCC) can be categorized under the following titles: autologous tumor cells, dendritic cells, genetically modified tumor cells, and protein/peptide. Although there are old studies on the implementation of vaccine therapies in RCC, researches have only been intensified recently. In addition to their effective potential for lengthening general survival, decreasing tumor burden and cancer development in long term, vaccine treatments are especially effective in metastatic RCC patients. We think that vaccine treatments would be applied more in near future since RCC are immunogenic. In this compilation, we will discuss vaccine therapies used in RCC, which urologists are not so familiar with, in the light of the up-to-date literature.

Emerging immunotherapeutic strategies targeting telomerases in genitourinary tumors

Telomerase activity and telomere length are essential for the pathogenesis of several human diseases, including genitourinary tumors. Telomerase constitutes a complex system that includes human telomerase reverse transcriptase (hTERT), human telomerase RNA component (hTR) and telomerase associated protein 1 (TEP1), which are overexpressed in tumor cells compared to normal cells and are involved in the carcinogenesis and progression of renal cell carcinoma (RCC), bladder (BC) and prostate cancer (PCa). In addition, telomerase degraded peptide fragments expressed on the surface of tumor cells lead to their recognition by immune cells. On this scenario, in vitro and in vivo studies have shown effective anti-tumor activity of hTERT-tailored strategies in genitourinary tumors, including active immunotherapy with hTERT-peptide vaccines and passive immunotherapy with hTERT-transduced T cell infusion. This review emphasizes the role of telomerase in the carcinogenesis and progression of genitourinary tumors, thus underlying the potential of emerging telomerase-tailored immunotherapies in these patients.

Immunomonitoring reveals interruption of anergy after vaccination in a case of type-2-papillary renal cell carcinoma

With the enormous and growing interest in the clinical application of immunotherapy, we are currently facing the need to accurately monitor the immune function of cancer patients. Here, we describe changes in the immune status of a patient with metastatic type-2-papillary renal cell carcinoma, before and after surgery and subsequent immunotherapy with a dendritic cell-tumor cell hybrid vaccine. Through the accurate assessment of monocyte-derived dendritic cells (Mo-DCs) function, we show that Mo-DCs were freed from tumor-induced maturation blockage by tumor resection surgery, while Mo-DCs-tumor induced suppression and anergy were only interrupted by the vaccination treatment. Our data suggest that the evaluation of Mo-DCs' function may provide a powerful and precise tool to monitor immune restoration in cancer patients.

Expression and prognostic role of MEKK3 and pERK in patients with renal clear cell carcinoma

Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is an important serine/threonine protein kinase and a member of the MAPK family. MEKK3 can effectively activate the MEK/ERK signaling pathway and promote an autocrine growth loop critical for tumor genesis, cell proliferation, terminal differentiation, apoptosis and survival. To explore the relationship between MEKK3 and cell apoptosis, clinicopathology and prognosis, we characterize the expression of MEKK3, pERK and FoxP3 in the renal clear cell carcinoma (RCCC). Protein expression was detected by tissue microarray and immunochemistry in 46 cases of RCCC and 28 control cases. Expression levels of CD3+ ,CD3+CD4+,CD3+CD8+,CD4+CD25+, CD4+CD25+ FoxP3+ were assessed by flow cytometry and analyzed for their association with pathological factors, correlation and prognosis in RCCC. Expression of MEKK3, pERK and FoxP3 was significantly up-regulated in RCCC as compared to control levels (p<0.01), associated with pathological grade (p<0.05)and clinical stage (p<0.05). CD4+CD25+ Foxp3+ Treg cells were also significantly increased in RCCC patients (p<0.05). Cox multivariate regression analysis showed that MEKK3, pERK expression and patholigical stage were independent prognostic factors in patients with RCCC (p<0.05). MEKK3 can be used as an important marker of early diagnosis and prognostic evaluation in RCCC. It may be associated with imbalance of anti-tumor immunity and overexpression of pERK. Expression of MEKK3 and pERK are significantly increased in RCCC, with protein expression and clinical stage acting as independent prognostic factors.

Nuclear Receptor 4A1 (NR4A1) as a Drug Target for Renal Cell Adenocarcinoma

The orphan nuclear receptor NR4A1 exhibits pro-oncogenic activity in cancer cell lines. NR4A1 activates mTOR signaling, regulates genes such as thioredoxin domain containing 5 and isocitrate dehydrogenase 1 that maintain low oxidative stress, and coactivates specificity protein 1 (Sp1)-regulated pro-survival and growth promoting genes. Transfection of renal cell carcinoma (RCC) ACHN and 786-O cells with oligonucleotides that target NR4A1 results in a 40–60% decrease in cell proliferation and induction of apoptosis. Moreover, knockdown of NR4A1 in RCC cells decreased bcl-2, survivin and epidermal growth factor receptor expression, inhibited of mTOR signaling, induced oxidative and endoplasmic reticulum stress, and decreased TXNDC5 and IDH1. We have recently demonstrated that selected 1,1-bis(3'-indolyl)-1-(p-substituted phenyl)methane (C-DIM) compounds including the p-hydroxyphenyl (DIM-C-pPhOH) and p-carboxymethyl (DIM-C-pPhCO₂Me) analogs bind NR4A1 and act as antagonists. Both DIM-C-pPhOH and DIM-C-pPhCO₂Me inhibited growth and induced apoptosis in ACHN and 786-O cells, and the functional and genomic effects of the NR4A1 antagonists were comparable to those observed after NR4A1 knockdown. These results indicate that NR4A1 antagonists target multiple growth promoting and pro-survival pathways in RCC cells and in tumors (xenograft) and represent a novel chemotherapy for treating RCC.

Hybrid paclitaxel and gold nanorod-loaded human serum albumin nanoparticles for simultaneous chemotherapeutic and photothermal therapy on 4T1 breast cancer cells

The use of human serum albumin nanoparticles (HSAPs) as a drug carrier system for cancer treatment has proven successful through current marketable clinical formulations. Despite this success, there is a current lack of multifunctional HSAPs, which offer combinational therapies of more than one proven technique. Gold nanorods (AuNRs) have also shown medicinal promise due to their photothermal therapy capabilities. In this study, a desolvation and cross-linking approach was employed to successfully encapsulate gold nanorods into HSAPs simultaneously with the chemotherapeutic drug paclitaxel (PAC); forming PAC-AuNR-HSAPs with desirable overall particle sizes of 299 ± 6 nm. The loading efficiency of paclitaxel into PAC-AuNR-HSAPs reached up to 3 μg PAC/mg HSA. The PAC-AuNR-HSAPs experienced photothermal heating; with the bulk particle solution reaching up to 46 °C after 15 min of near-IR laser exposure. This heat increase marked the successful attainment of the temperature necessary to cause severe cellular hyperthermia and necrosis. The encasement strategy facilitated a colloidal hybrid treatment system capable of enhanced permeability and retention effects, photothermal ablation of cancer cells, and release of the active paclitaxel of up to 188 ng (from PAC-AuNR-HSAPs created with 30 mg HSA) in a single 15 min irradiation session. When treated with PAC-AuNR-HSAPs containing 20 μg PAC/mL particle solution, 4T1 mouse breast cancer cells experienced ∼82% cell death without irradiation and ∼94% cell death after just one irradiation session. The results for PAC-AuNR-HSAPs were better than that of free PAC, which only killed ∼77% of the cells without irradiation and ∼80% with irradiation. The hybrid particle system also lends itself to future customizable external functionalities via conjugated targeting ligands, such as antibodies. Internal entrapment of patient tailored medication combinations are also possible with this combination treatment platform, which may result in improved quality of life for those undergoing treatment.

The expression and role of MEKK3 in renal clear cell carcinoma

To explore the relationship between Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3(MEKK3) and cell apoptosis, clinicopathology, and prognosis, we characterize the expression of MEKK3, survivin and stat3 in renal clear cell carcinoma (RCCC). The expressions were measured by RT-PCR and Western blot from 15 cases of RCCC and 15 cases of control group (CG). Protein expression was detected by tissue microarray and immunochemistry in 98 cases of RCCC, 28 cases of CG. Expression patterns were analyzed for their association with pathological factors, correlation and prognosis in RCCC. Expression of MEKK3, survivin and stat3 mRNA was significantly higher in RCCC than in CG (P < 0.01). MEKK3, survivin and stat3 expression differed significantly between pathological grade (P < 0.05) and clinical stage (P < 0.05). MEKK3 expression was positively correlated with survivin and stat3 (P < 0.01). Furthermore, we investigated the role of MEKK3 in RCCC using the technique of RNA silencing via small interfering (siRNA) in ACHN cells. The results indicated that the targeted depletion of MEKK3 caused a dramatic massive apoptotic cell death. Kaplan-Meier survival analysis showed that MEKK3 and survivin expression, pathological grade, and clinical stage reduced cumulative survival. Cox multivariate regression analysis showed that MEKK3, survivin, and clinical staging were independent prognostic factors in renal cancer (P < 0.05). MEKK3 can be used as an important marker of prognostic evaluation in RCCC. The mechanism may be closely related to cell apoptosis. Targeted therapy of MEKK3 may provide a new strategy for treatment of chemotherapeutic-resistant tumors.