Expression of Receptor Tyrosine Kinases on Peripheral Blood Mononuclear Cells and Tumor-Infiltrating Lymphocytes in Patients with Renal Cell Carcinoma and Healthy Donors

Evaluation of the clinical significance of lymphocyte subsets and myeloid suppressor cells in patients with renal carcinoma

PURPOSE

The purpose of this study was to analyze the expression patterns of immune cells in renal cancer patients, including myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), CD3 + /CD4 + T cells, CD3 + / CD8 + T cells, and CD3- CD16 + CD56 + cells. In addition, this study will explore the correlation between these immune markers and the progression of renal cell carcinoma and evaluate their potential application in predicting the therapeutic effect of renal cell carcinoma.

METHODS

In this study, 80 renal cancer patients who received treatment in our hospital from October 2022 to December 2023 were selected as the research object and 50 healthy people who underwent a physical examination at the same time were selected as the control group. All participants had a 3 ml venous blood sample taken in the morning on an empty stomach. All patients with renal cell carcinoma have been confirmed by histopathological diagnosis. Clinicopathological data including age, gender, BMI, clinical stage, tumor size and pathological type were collected.MDSC, Treg, CD3 + /CD4 + T cells, CD3 + /CD8 + T cells, the ratio of CD3 + /CD4 + T cells/CD3 + /CD8 + T cell and the expression level of CD3-CD16 + CD56 + cells were detected by flow cytometry.

RESULTS

Through the detection of flow cytometry, we observed that there was no significant difference in gender, age, BMI and other baseline characteristics between renal cancer patients and healthy controls, and the P value was greater than 0.05. However, in the analysis of peripheral blood immune cell subsets, including CD3 + /CD4 + , CD3 + /CD8 + , CD3 + /CD4 + /CD3 + /CD8 + ratio, NK cells, regulatory T cells (T-reg), polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) and mononuclear myeloid-derived suppressor cells (M-MDSC) were significantly different between renal cell carcinoma group and normal control group (P < 0.05). Specifically, the expression levels of CD3 + /CD4 + and CD3 + /CD8 + cells in renal cancer patients were lower than those in normal subjects, while the expression levels of T-reg, PMN-MDSC and M-MDSC were relatively high. (2) In the flow cytometry analysis, the expression level of immune cell subsets in the peripheral blood of renal cancer patients was detected.The results showed that there was no significant correlation between the expression of CD3 + /CD4 + , CD3 + /CD8 + , CD3 + /CD4 + /CD3 + /CD8 + ratio, NK cells, T-reg cells, PMN-MDSC and M-MDSC and the sex, age, BMI and pathological type of the patients. These differences were not statistically significant (P > 0.05).At the same time, CD3 + /CD8 + T cells, the ratio of CD3 + /CD4 + /CD3 + /CD8 + and the expression level of NK cells were not significantly correlated with tumor size and clinical stage (P > 0.05). However, the expression levels of CD3 + /CD4 + cells, M-MDSC, PMN-MDSC, and T-reg cells were statistically significantly different with tumor size and clinical stage (P < 0.05).There was a significant difference between these indexes and lymph node metastasis (P < 0.05). (3) The results of Logistic regression analysis showed that the low expression of CD3 + /CD4 + lymphocytes and the high expression of T-reg, PMN-MDSC and M-MDSC in peripheral blood may be related to the clinical stage of renal cell carcinoma.

CONCLUSION

(1) Compared with healthy individuals, patients with renal cell carcinoma showed a significant decrease in CD3 + /CD4 + T cells, CD3 + /CD8 + T cells and CD3-CD16 + CD56 + cells, while the CD4 + /CD8 + ratio increased. In addition, the number of PMN-MDSC, M-MDSC and T-reg cells was significantly increased compared with the normal population, indicating that the immune system function of patients was impaired. (2) The expression levels of CD3 + /CD4 + , PMN-MDSC, M-MDSC and T-reg were different in tumor size and clinical stage. Specifically, the expression levels of PMN-MDSC, M-MDSC, and T-reg increased correspondingly with the increase in tumor diameter and the progression of the clinical stage.

A novel anti-FGFR1 monoclonal antibody OM-RCA-01 exhibits potent antitumor activity and enhances the efficacy of immune checkpoint inhibitors in lung cancer models

Background

Fibroblast growth factor receptor 1 (FGFR1) plays a crucial role in carcinogenesis. Exploring the combination of the novel humanized monoclonal anti-FGFR1 antibody OM-RCA-01 and immunotherapy was intriguing due to involvement of FGFR1 in mechanisms of resistance to checkpoint inhibitors.

Materials and methods

Lung cancer A549, exhibiting distinct levels of FGFR1 expression, were cultured in basic FGF medium with OM-RCA-01 supplementation. The efficacy of antibody monotherapy was validated in a lung cancer xenograft study. To investigate whether OM-RCA-01 could enhance the efficacy of immunotherapy in vitro and in vivo, mixed lymphocyte reaction/Staphylococcal enterotoxin B assays and FGFR1/programmed death-ligand 1-positive patient-derived xenograft model were established.

Results

The antibody effectively suppressed receptor phosphorylation, resulting in inhibited cell proliferation. OM-RCA-01 led to a substantial delay in tumor growth compared to non-specific immunoglobulin G in a xenograft study. The median tumor volume was 1048.5 mm3 and 2174 mm3 in the study and vehicle groups, respectively, representing a twofold difference in favor of the anti-FGFR1 antibody. In vitro, the combination of nivolumab and OM-RCA-01 resulted in higher levels of interferon gamma and interleukin-2 release compared with nivolumab alone. In vivo, pembrolizumab in combination with OM-RCA-01 produced a greater inhibitory effect on tumor growth compared with vehicle and pembrolizumab alone. The curve plateaued, indicating minimal tumor growth from day 16 onwards in the combination group. The OM-RCA-01 demonstrated no toxicity, even at therapeutic doses or higher doses.

Conclusions

Our preclinical studies demonstrate that OM-RCA-01 exhibits robust activity with minimal toxicity. Combining an anti-FGFR1 antibody with a checkpoint inhibitor may enhance the efficacy of both drugs. However, further studies are needed to elucidate the mechanism of this interaction.

Assessment of the Circulating PD-1 and PD-L1 Levels and P53 Expression as a Predictor of Relapse in Pediatric Patients with Wilms Tumor and Hypernephroma

Background/Objectives: Wilms tumor (WT) is the most common form of pediatric renal tumor, accounting for over 90% of cases followed by hypernephroma. Some pediatric patients with WT (10%) experience relapse or metastasis and have poor survival rates. PD-L1 assists cancer cells in escaping damage from the immune system. P53 mutations are found in relapsed WT tumor samples. We hypothesized that testing circulating PD-1 and PD-L1 and P53 expression levels could offer a simple method to predict patient relapse and explore novel treatments for pediatric WTs and hypernephroma. Methods: Flow cytometric detection of cPD-1, cPD-L1, and P53 expression in relapsed and in-remission WT and hypernephroma before and after one year of chemotherapy was performed. Results: Our data shows increased levels of cPD-L1 in relapsed pediatric patients with WT or hypernephroma before and after chemotherapy. There were also slight and significant increases in cPD-1 levels in relapsed groups before chemotherapy. Additionally, we observed significant decreases in P53 expression after one year of chemotherapy in relapsed pediatric patients. Conclusions: Our study found that circulating PD-L1 can be used as a predictor marker for WT and hypernephroma relapse. In conclusion, these circulating markers can assist in monitoring relapse in WT and hypernephroma patients without the need for several biopsies.

Nivolumab: 5 Years Since FDA Approval of the First Checkpoint Inhibitor for Renal Cell Carcinoma

On November 23, 2015, the US Food and Drug Administration (FDA) approved nivolumab for the treatment of metastatic renal cell carcinoma (RCC), thus opening a new era of immunotherapy for this tumor. This review summarizes the 5-year experience of studying and using nivolumab in RCC patients.