Different Cytokine and Chemokine Expression Patterns in Malignant Compared to Those in Nonmalignant Renal Cells

Pleiotropic Devitalization of Renal Cancer Cells by Non-Invasive Physical Plasma: Characterization of Molecular and Cellular Efficacy

Renal cell carcinoma (RCC) is the third most common urological tumor and has an extremely poor prognosis after metastasis has occurred. Therapeutic options are highly restricted, primarily due to resistance to classical chemotherapeutics. The development of new, innovative therapeutic procedures is thus of great urgency. In the present study, the influence of non-invasive physical plasma (NIPP) on malignant and non-malignant renal cells is characterized. The biological efficacy of NIPP has been demonstrated in malignant renal cell lines (786-O, Caki-1) and non-malignant primary human renal epithelial cells (HREpC). The cell responses that were experimentally examined were cell growth (cell number determination, calculation of growth rate and doubling time), cell motility (scratch assay, invasiveness assay), membrane integrity (uptake of fluorescent dye, ATP release), and induction of apoptosis (TUNEL assay, caspase-3/7 assay, comet assay). A single NIPP treatment of the malignant cells significantly inhibited cell proliferation, invasiveness, and metastasis. This treatment has been attributed to the disruption of membrane functionality and the induction of apoptotic mechanisms. Comparison of NIPP sensitivity of malignant 786-O and Caki-1 cells with non-malignant HREpC cells showed significant differences. Our results suggest that renal cancer cells are significantly more sensitive to NIPP than non-malignant renal cells. Treatment with NIPP could represent a promising innovative option for the therapy of RCC and might supplement established treatment procedures. Of high clinical relevance would be the chemo-sensitizing properties of NIPP, which could potentially allow a combination of NIPP treatment with low-dose chemotherapy.

Multiregional single-cell proteogenomic analysis of ccRCC reveals cytokine drivers of intratumor spatial heterogeneity

Intratumor heterogeneity (ITH) represents a major challenge for anticancer therapies. An integrated, multidimensional, multiregional approach dissecting ITH of the clear cell renal cell carcinoma (ccRCC) tumor microenvironment (TME) is employed at the single-cell level with mass cytometry (CyTOF), multiplex immunofluorescence (MxIF), and single-nucleus RNA sequencing (snRNA-seq) and at the bulk level with whole-exome sequencing (WES), RNA-seq, and methylation profiling. Multiregional analyses reveal unexpected conservation of immune composition within each individual patient, with profound differences among patients, presenting patient-specific tumor immune microenvironment signatures despite underlying genetic heterogeneity from clonal evolution. Spatial proteogenomic TME analysis using MxIF identifies 14 distinct cellular neighborhoods and, conversely, demonstrated architectural heterogeneity among different tumor regions. Tumor-expressed cytokines are identified as key determinants of the TME and correlate with clinical outcome. Overall, this work signifies that spatial ITH occurs in ccRCC, which may drive clinical heterogeneity and warrants further interrogation to improve patient outcomes.

Localized PD-1 Blockade in a Mouse Model of Renal Cell Carcinoma

Herein we report the impact of localized delivery of an anti-mouse PD-1-specific monoclonal antibody (aPD1) on Renca tumors in the resulting T cell responses and changes in broader immune gene expression profiles. Renca is a BALB/c mice syngeneic tumor that has been used to model human renal cell carcinoma In this study, T cell subsets were examined in tumors and draining lymph nodes of mice treated with localized PD-1 with and without the addition of adenosine deaminase (ADA), an enzyme that catabolizes adenosine (ADO), identified as an immune checkpoint in several types of human cancers. The biologics, aPD1, or aPD1 with adenosine deaminase (aPD1/ADA), were formulated with the self-assembling peptides Z15_EAK to enhance retention near the tumor inoculation site. We found that both aPD1 and aPD1/ADA skewed the local immune milieu towards an immune stimulatory phenotype by reducing Tregs, increasing CD8 T cell infiltration, and upregulating IFNɣ. Analysis of tumor specimens using bulk RNA-Seq confirmed the impact of the localized aPD1 treatment and revealed differential gene expressions elicited by the loco-regional treatment. The effects of ADA and Z15_EAK were limited to tumor growth delay and lymph node enlargement. These results support the notion of expanding the use of locoregional PD-1 blockade in solid tumors.

TAM-ing the CIA-Tumor-Associated Macrophages and Their Potential Role in Unintended Side Effects of Therapeutics for Cancer-Induced Anemia

Cancer-induced anemia (CIA) is a common consequence of neoplasia and has a multifactorial pathophysiology. The immune response and tumor treatment, both intended to primarily target malignant cells, also affect erythropoiesis in the bone marrow. In parallel, immune activation inevitably induces the iron-regulatory hormone hepcidin to direct iron fluxes away from erythroid progenitors and into compartments of the mononuclear phagocyte system. Moreover, many inflammatory mediators inhibit the synthesis of erythropoietin, which is essential for stimulation and differentiation of erythroid progenitor cells to mature cells ready for release into the blood stream. These pathophysiological hallmarks of CIA imply that the bone marrow is not only deprived of iron as nutrient but also of erythropoietin as central growth factor for erythropoiesis. Tumor-associated macrophages (TAM) are present in the tumor microenvironment and display altered immune and iron phenotypes. On the one hand, their functions are altered by adjacent tumor cells so that they promote rather than inhibit the growth of malignant cells. As consequences, TAM may deliver iron to tumor cells and produce reduced amounts of cytotoxic mediators. Furthermore, their ability to stimulate adaptive anti-tumor immune responses is severely compromised. On the other hand, TAM are potential off-targets of therapeutic interventions against CIA. Red blood cell transfusions, intravenous iron preparations, erythropoiesis-stimulating agents and novel treatment options for CIA may interfere with TAM function and thus exhibit secondary effects on the underlying malignancy. In this Hypothesis and Theory, we summarize the pathophysiological hallmarks, clinical implications and treatment strategies for CIA. Focusing on TAM, we speculate on the potential intended and unintended effects that therapeutic options for CIA may have on the innate immune response and, consequently, on the course of the underlying malignancy.

Role of the BMP6 protein in breast cancer and other types of cancer

The BMP6 protein (Bone Morphogenetic Protein 6) is part of the superfamily of transforming growth factor-beta (TGF-β) ligands, participates in iron homeostasis, inhibits invasion by increasing adhesions and cell-cell type interactions and induces angiogenesis directly on vascular endothelial cells. BMP6 is coded by a tumor suppressor gene whose subexpression is related to the development and cancer progression; during neoplastic processes, methylation is the main mechanism by which gene silencing occurs. This work presents a review on the role of BMP6 protein in breast cancer (BC) and other types of cancer. The studies carried out to date suggest the participation of the BMP6 protein in the epithelial-mesenchymal transition (EMT) phenotype, cell growth and proliferation; however, these processes are affected in a variable way in the different types of cancer, the methylated CpG sites in BMP6 gene promoter, as well as the interaction with other proteins could be the cause of such variation.

Determination of In Vitro Membrane Permeability by Analysis of Intracellular and Extracellular Fluorescein Signals in Renal Cells

BACKGROUND/AIM

The structural integrity of the eukaryotic cytoplasmic membrane is of crucial importance for its cell biological function and thus for the survival of the cell. Physical and chemical noxae can interact in various ways with components of the cytoplasmic membrane, influence its permeability and thus mediate toxic effects. In the study presented, changes in membrane permeability were quantified by intracellular accumulation of a fluorescent dye and by the release of the fluorescent dye from dye-loaded cells.

MATERIALS AND METHODS

Non-malignant (RC-124) and malignant (786-O, Caki-1) renal cells were permeabilized with different concentrations of Triton X-100. The permeability of the membrane was determined at the single-cell level by the uptake of the dye into the cell inner by flow cytometry. In addition, a fluorescence plate reader was used to detect and quantify the release of the dye into the cell culture supernatant.

RESULTS

Both malignant and non-malignant cells showed a dose-dependent alteration of membrane permeability after treatment with Triton X-100. In the presence of the fluorescent dye, significantly more dye was introduced into the permeabilized cells compared to control incubations. Vice versa, Triton X-100-treated and dye-loaded cells released significantly more dye into the cell culture supernatant.

CONCLUSION

The combination of measurement of intracellular accumulated and extracellular released dye can quantifiably detect changes in membrane permeability due to cell-membrane damage. The combination of two different measurement methods offers additional value in reliable detection of membrane-damaging, potentially toxic influences.