Immunologic mechanisms in RCC and allogeneic renal transplant rejection

Exploring the mechanism of BK polyomavirus-associated nephropathy through consensus gene network approach

BK polyomavirus-associated nephropathy occurs in kidney transplant recipients under immunosuppressive treatment. BK polyomavirus is implicated in cancer development and invasion, and case reports of renal cell carcinoma and urothelial carcinoma possibly associated with BK polyomavirus has been reported. Further, it has been suggested that the immune responses of KT-related diseases could play a role in the pathogenesis and progression of renal cell carcinoma. Thus, we thought to examine the relationship between BK polyomavirus-associated nephropathy and renal cell carcinoma in terms of gene expression. To identify the common and specific immune responses involved in kidney transplantation-related diseases with a specific focus on BK polyomavirus-associated nephropathy, we performed consensus weighted gene co-expression network analysis on gene profile datasets of renal biopsy samples from different institutions. After the identification of gene modules and validation of the obtained network by immunohistochemistry of the marker across kidney transplantation-related diseases, the relationship between prognosis of renal cell carcinoma and modules was assessed. We included the data from 248 patients and identified the 14 gene clusters across the datasets. We revealed that one cluster related to the translation regulating process and DNA damage response was specifically upregulated in BK polyomavirus-associated nephropathy. There was a significant association between the expression value of hub genes of the identified cluster including those related to cGAS-STING pathway and DNA damage response, and the prognosis of renal cell carcinoma. The study suggested the potential link between kidney transplantation-related diseases, especially specific transcriptomic signature of BK polyomavirus associated nephropathy and renal cell carcinoma.

Skin cancer outcomes and risk factors in renal transplant recipients: Analysis of organ procurement and transplantation network data from 2000 to 2021

Purpose

Posttransplant skin cancer is the most common malignancy after patients have undergone renal transplantation. Through comprehensive observation with a large sample size nationwide, understanding the risk factors and outcome of posttransplant skin cancer will help to develop appropriate patient surveillance and disease prevention strategies.

Materials and methods

This retrospective population-based cohort study was based on Organ Procurement and Transplantation Network data released in March 2021. Characteristics and outcomes, including patient survival and graft survival of recipients, were compared. Risk factors for posttransplant skin cancer, cancer onset momentum, and mortality were determined.

Results

A total of 199,564 renal transplant recipients were included. After renal transplantation, 7,334 (3.68%), 6,093 (3.05%), and 936 (0.47%) were diagnosed with squamous cell carcinoma, basal cell carcinoma, and melanoma, respectively. Skin cancer was the major cause of death (squamous cell carcinoma: 23.8%, basal cell carcinoma: 18%, and melanoma: 41.6%). Five-year survival rates ranked from best to worst were as follows: basal cell carcinoma (96.7 [95% confidence interval: 96.3-97.2]%), squamous cell carcinoma (94.1 [93.5-94.6]%), melanoma (89.7 [87.7-91.6]%), and cancer-free (87.4 [87.2-87.5]%) (p < 0.001 for all except melanoma vs. cancer-free, p = 0.534). Regarding graft survival, death-censored graft survival, posttransplant skin cancer, and melanoma were significantly better than the cancer-free group (p < 0.001). Independent risk factors for developing posttransplant skin cancer included older age, male sex, Caucasian race, pretransplant malignancy, polycystic kidney disease-induced end-stage renal disease (ESRD), retransplantation, private health insurance, T-cell depletion induction, and tacrolimus/mycophenolic acid use. Caucasian race and pretransplant malignancy were independent risk factors for posttransplant skin cancer onset momentum. Male sex, Caucasian race, pretransplant malignancy, hypertension- or diabetes-induced ESRD, retransplantation, diabetes history, deceased donor, cyclosporin, and mTOR inhibitor use were independent risk factors for posttransplant skin cancer mortality.

Conclusion

Although posttransplant skin cancer is a major cause of recipient death, information regarding its impact on patient and graft survival is limited. Given the differences regarding risk factors for posttransplant skin cancer incidence, onset momentum, and mortality, personalized approaches to screening may be appropriate to address the complex issues encountered by kidney transplant recipients.

Identifying tumor antigens and immune subtypes of renal cell carcinoma for immunotherapy development

Renal cell carcinoma (RCC) is one of the leading causes of death in men. Messenger ribonucleic acid (mRNA) vaccines may be an attractive means to achieve satisfactory results. Cancer immunotherapy is a promising cancer treatment strategy. However, immunotherapy is not widely used in renal cell carcinoma, as only a few patients show a positive response. The present study aimed to identify potential antigens associated with renal cell carcinoma to develop an anti-renal cell carcinoma mRNA vaccine. Moreover, the immune subtypes of renal cell carcinoma cells were determined. The Cancer Genome Atlas (TCGA) analysis revealed gene expression profiles and clinical information. Antigen-presenting cells infiltrated the immune system using Tumor Immune Estimation Resource (TIMER) tool (http://timer.cistrome.org/). GDSC (Genomics of Drug Sensitivity in Cancer) database were used to estimate drug sensitivity. The 13 immune-related genes discovery could be targets for immunotherapy in renal cell carcinoma patients, as they were associated with a better prognosis and a higher level of antigen-presenting cells. These immune subtypes have significant relationships with immunological checkpoints, immunogenic cell death regulators, and RCC prognostic variables. Furthermore, DBH-AS1 was identified as a potential antigen for developing an mRNA vaccine. The CCK8 assay demonstrated that the proliferative capacity of 786-O and Caki-1 cells overexpressing DBH-AS1 was higher than in the control group. In addition, transwell assay revealed that 786-O and Caki-1 cells overexpressing DBH-AS1 showed higher invasion capacity compared with control. This study provides a theoretical basis for the development of mRNA vaccines. Our findings suggest that DBH-AS1 could be potential antigens for developing RCC mRNA vaccines.

Profiling the Resident and Infiltrating Monocyte/Macrophages during Rejection following Kidney Transplantation

Immune tolerance research is essential for kidney transplantation. Other than antibody and T cell-mediated immune rejection, macrophage-mediated innate immunity plays an important role in the onset phase of transplantation rejection. However, due to the complexity of the kidney environment as well as its diversity and low abundance, studies pertaining to monocyte/macrophages in kidney transplantation require further elucidation. In this study, kidney samples taken from healthy human adults and biopsy specimens from patients undergoing rejection following kidney transplantation were analysed and studied. By conducting a single-cell RNA analysis, the type and status of monocyte/macrophages in kidney transplantation were described, in which monocyte/macrophages were observed to form two different subpopulations: resident and infiltrating monocyte/macrophages. Furthermore, previously defined genes were mapped to all monocyte/macrophage types in the kidney and enriched the differential genes of the two main subpopulations using gene expression databases. Considering that various cases of rejection may be of the monocyte/macrophage type, the present data may serve as a reference for studies regarding immune tolerance following kidney transplantation.

Active CMV and EBV infections in renal transplant recipients with unexplained fever and elevated serum creatinine

Proper identification of active cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are helpful for monitoring antiviral treatment in transplant recipients. Qualitative and quantitative CMV, EBV DNA PCR techniques in the context of serological tests are performed for early detection and differentiation of active and latent CMV and EBV infections in renal transplantation. Basically, 129 renal transplanted recipients monitored carefully and hospitalized for unexplained elevated creatinine levels or high fever and 21 of their donors were studied. CMV DNA was detected in 63.5% of the febrile episodes following transplantation and in 46.42% of readmitted patients using qualitative PCR method. In the first group, 15% of the patients and in the second group 42.85% of the patients had copy numbers more than cutoff point (900 copies/mL). Cutoff point had 100% sensitivity and 82.5% specificity for active and symptomatic CMV infection. Only 15.5% of the subjects were positive for EBV infection by qualitative PCR method. Among them 5% had >2000 copies/mL and were symptomatic. One subject with a history of three times hospitalization had higher EBV viral load and developed post-transplant lymphoproliferative disorder. CMV load was significantly correlated with elevated creatinine levels (OR = 3.1, p = 0.006), abnormal heart sounds (OR = 4.7; p = 0.02) and hypertension (OR = 3.6; p = 0.03). Only qRT-PCR could differentiate between latent and active infections and might be clinically useful for monitoring symptomatic CMV and EBV infections and initiation of the antiviral therapy. Elevated creatinine levels, hypertension, and abnormal heart sounds could be considered as main manifestations of HCMV infection in kidney recipients.

Intratumoral CD14+ Cells and Circulating CD14+HLA-DRlo/neg Monocytes Correlate with Decreased Survival in Patients with Clear Cell Renal Cell Carcinoma

PURPOSE

Immunotherapeutic strategies to treat patients with renal cell carcinoma (RCC) offer new opportunities for disease management. Further improvements to immunotherapy will require additional understanding of the host response to RCC development.

EXPERIMENTAL DESIGN

Using a novel approach to understanding the immune status of cancer patients, we previously showed that patients with a certain immune profile had decreased overall survival. Here, we examine in more detail the phenotypic changes in peripheral blood and the potential consequences of these changes in RCC patients.

RESULTS

We found that CD14(+)HLA-DR(lo/neg) monocytes were the most predominant phenotypic change in peripheral blood of RCC patients, elevated nearly 5-fold above the average levels measured in healthy volunteers. Intratumoral and peritumoral presence of CD14 cells was an independent prognostic factor for decreased survival in a cohort of 375 RCC patients. The amount of peripheral blood CD14(+)HLA-DR(lo/neg) monocytes was found to correlate with the intensity of CD14 staining in tumors, suggesting that the measurement of these cells in blood may be a suitable surrogate for monitoring patient prognosis. The interaction of monocytes and tumor cells triggers changes in both cell types with a loss of HLA-DR expression in monocytes, increases of monocyte survival factors such as GM-CSF in tumors, and increased production of angiogenic factors, including FGF2.

CONCLUSIONS

Our results suggest a model of mutually beneficial interactions between tumor cells and monocytes that adversely affect patient outcome.

Red cell distribution width is associated with presence, stage, and grade in patients with renal cell carcinoma

It has been reported that red blood cell width (RDW) is a marker associated with the presence and adverse outcomes of various diseases. However, no data are available on the correlation of RDW with presence, stage, and grade in patients with renal cell carcinoma (RCC) yet. By retrospectively analyzing clinical and laboratory data at baseline of histologically confirmed RCC cases and controls, the present study demonstrated that the RDW values were significantly higher in patients with RCC than those in controls, and the baseline RDW value was independently associated with the presence of RCC. Besides, the data revealed a positive association between RCC stage and grade and the level of RDW. These findings may have important clinical implications due to future application using a RDW value in predicting RCC.

Dramatic early event in chronic allograft nephropathy: increased but not decreased expression of MMP-9 gene

OBJECTIVE

The infiltration of mononuclear cells and replication and migration of smooth muscle cells (SMCs) from media into the intima in the vascular wall are the cardinal pathological changes in the early stage of chronic allograft nephropathy (CAN). But the mechanism is unclear. Therefore we investigated the role of matrix metalloproteinase 9 (MMP-9) and its interaction with TGF-beta1, tubulointerstitial mononuclear cells infiltration and migration of SMCs in the early stage of CAN.

METHODS

Kidneys of Fisher (F334) rats were orthotopically transplanted into bilaterally nephrectomized Lewis (LEW) recipients. To suppress an initial episode of acute rejection, rats were briefly treated with cyclosporine A (1.5 mg/kg/day) for the first 10 days. Animals were harvested at 12 weeks after transplantation for histological, immunohistochemistry and molecular biological analysis.

RESULTS

The expression of MMP-9 was up-regulated in interstitium and vascular wall in the early stage of CAN, where there were interstitial mononuclear cells infiltration and SMCs migration and proliferation. Moreover the expression of MMP-9 were positively correlated with the degree of interstitial mononuclear cells infiltration, the quantity of SMCs in arteriolar wall, and also the increased TFG-beta1 expression in the tubulointerstitium and arteriolar wall.

CONCLUSIONS

MMP-9 may play an important role in the mechanism of pathological changes during the earlier period of CAN.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1582313332832700.

[Prostate carcinoma: vaccination as a new option for treatment]

Immune therapy and tumor cell vaccination is a challenging option in prostate cancer therapy, especially as side effects rarely occur. This review highlights recent developments in vaccination therapy of prostate cancer. The FDA approved antigen presenting cell vaccine Sipuleucel-T is described and new strategies of immune therapy like RNA and peptide vaccination are discussed in detail. Currently the effect of prostate cancer vaccination has still limitations, at least partially due to the immune suppressive effects of the tumor microenvironment and regulatory T cells, which suppress the immune effector function. To overcome these hurdles the concept of immune checkpoint modulation, which has the aim to break tolerance mechanisms, is discussed. Potential clinical therapies of checkpoint modulation are outlined.