DNA Methylation-Based Panel Predicts Survival of Patients With Clear Cell Renal Cell Carcinoma and Its Correlations With Genomic Metrics and Tumor Immune Cell Infiltration

Epigenetic regulation and therapeutic targets in the tumor microenvironment

The tumor microenvironment (TME) is crucial to neoplastic processes, fostering proliferation, angiogenesis and metastasis. Epigenetic regulations, primarily including DNA and RNA methylation, histone modification and non-coding RNA, have been generally recognized as an essential feature of tumor malignancy, exceedingly contributing to the dysregulation of the core gene expression in neoplastic cells, bringing about the evasion of immunosurveillance by influencing the immune cells in TME. Recently, compelling evidence have highlighted that clinical therapeutic approaches based on epigenetic machinery modulate carcinogenesis through targeting TME components, including normalizing cells' phenotype, suppressing cells' neovascularization and repressing the immunosuppressive components in TME. Therefore, TME components have been nominated as a promising target for epigenetic drugs in clinical cancer management. This review focuses on the mechanisms of epigenetic modifications occurring to the pivotal TME components including the stroma, immune and myeloid cells in various tumors reported in the last five years, concludes the tight correlation between TME reprogramming and tumor progression and immunosuppression, summarizes the current advances in cancer clinical treatments and potential therapeutic targets with reference to epigenetic drugs. Finally, we summarize some of the restrictions in the field of cancer research at the moment, further discuss several interesting epigenetic gene targets with potential strategies to boost antitumor immunity.

SPI1 is a prognostic biomarker of immune infiltration and immunotherapy efficacy in clear cell renal cell carcinoma

BACKGROUND

Spi-1 proto-oncogene (SPI1), which encodes an ETS-domain transcription factor, can activate gene expression in myeloid and lymphoid lineages. The role of SPI1 in the tumor immune microenvironment in clear cell renal cell carcinoma (ccRCC) remains unknown. In this study, we investigated the possible role of SPI1 in ccRCC using an independent cohort and a comprehensive bioinformatics analysis.

MATERIALS AND METHODS

Quantitative real-time PCR, western blot and immunohistochemistry assays were used to compare the SPI1 expression levels between ccRCC tissues and normal tissues, analyze the relationships between SPI1 and CD68, CD8, CD4 expression levels, and explore the link between SPI1 and the efficacy of immunotherapy in our cohort. Tumor Immune Estimation Resource, UALCAN, cBioPortal, TISIDB database, and LinkedOmics database were used in our study.

RESULTS

SPI1 expression level was higher in ccRCC bulk tissues than in normal bulk tissues. SPI1 was an independent prognostic factor for poor overall survival and progression-free survival in patients with ccRCC. SPI1 expression was strongly related to the infiltration of immune cells and immune-related molecules. SPI1 was more highly expressed in tumor-infiltrating immune cells rather than in cancer cells. Non-responders to immunotherapy against ccRCC were more likely to express higher SPI1 levels than responders. Genes co-expressed with SPI1 primarily correlated with immune-related pathways.

CONCLUSIONS

SPI1 expression in tumor bulk tissues is associated with disease progression and poor prognosis, as well as high expression levels of immune markers and infiltration of immune cells. SPI1 can be used as a prognostic biomarker to monitor and evaluate immunotherapy efficacy.

Focus on the Dynamics of Neutrophil-to-Lymphocyte Ratio in Cancer Patients Treated with Immune Checkpoint Inhibitors: A Meta-Analysis and Systematic Review

Background: A number of studies have reported an association between the dynamics of neutrophil-to-lymphocyte ratio (NLR) and clinical efficacy in patients treated with immune checkpoint inhibitors (ICIs), but there is still a lack of a meta-analysis or systematic review. Methods: PubMed, Embase, Web of Science, and the Cochrane Library were searched until September 2022 for studies reporting on the association between the change in NLR after ICI treatment and clinical outcomes. Outcome measures of interest included: change in NLR before and after treatment, overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Results: A total of 4154 patients in 38 studies were included. The pooled percentage of patients with increased NLR was 49.7% (95CI%: 43.7−55.8%). Six studies discussing the change in NLR in patients with different tumor responses all showed that the NLR level in patients without response to immunotherapy may increase after ICI treatment. The upward trend in NLR was associated with shorter OS (pooled HR: 2.05, 95%CI: 1.79−2.35, p < 0.001) and PFS (pooled HR: 1.89, 95%CI: 1.66−2.14, p < 0.001) and higher ORR (pooled OR: 0.27, 95%CI: 0.19−0.39, p < 0.001), and downward trend in NLR was associated with longer OS (pooled HR: 0.49, 95%CI: 0.42−0.58, p < 0.001) and PFS (pooled HR: 0.55, 95%CI: 0.48−0.63, p < 0.001) and lower ORR (pooled OR: 3.26, 95%CI: 1.92−5.53, p < 0.001). In addition, post-treatment high NLR was associated with more impaired survival than baseline high NLR (pooled HR of baseline high NLR: 1.82, 95%CI: 1.52−2.18; pooled HR of post-treatment high NLR: 2.93, 95%CI: 2.26−3.81), but the NLR at different time points may have a similar predictive effect on PFS (pooled HR of baseline high NLR: 1.68, 95%CI: 1.44−1.97; pooled HR of post-treatment high NLR: 2.00, 95%CI: 1.54−2.59). Conclusions: The NLR level of tumor patients after ICI treatment is stable overall, but the NLR level in patients without response to immunotherapy may increase after ICI treatment. Patients with an upward trend in NLR after ICI treatment were associated with worse clinical outcomes; meanwhile, the downward trend in NLR was associated with better clinical outcomes. Post-treatment high NLR was associated with more impaired survival than baseline high NLR.

CD86 Molecule Might Be a Novel Immune-Related Prognostic Biomarker for Patients With Bladder Cancer by Bioinformatics and Experimental Assays

As one of the most common malignancies in the urinary system, bladder cancer (BC) occupies a high mortality and recurrence rate. BC carries an ominous prognosis. Thus, we aimed to identify a novel immune-related prognostic biomarker and therapeutic target for immunotherapy in the present study. We first constructed a co-expression network based on immune-related genes (IRGs). Two key modules showed high association with the clinical feature interested us most were further identified. Forty-five IRGs were screened out and regarded as hub genes in the co-expression network. We further constructed a protein-protein interaction (PPI) network, and five independent methods were used for hub gene identification. Three hub genes were identified in the present study. CD86 molecule (CD86) was screened out by performing overall survival (OS) analysis. Subsequent analyses by using some bioinformatics and experimental assays confirmed that CD86 was an immune-related prognostic biomarker, which might be a novel target for immunotherapy in BC. A small molecule drug named suloctidil was also identified, which showed potential for BC treatment.