Oncostatin M: From Intracellular Signaling to Therapeutic Targets in Liver Cancer

Involvement of multiple epigenetic mechanisms by altered DNA methylation from the early stage of renal carcinogenesis before proliferative lesion formation upon repeated administration of ochratoxin A

Ochratoxin A (OTA) is a rat renal carcinogen that induces karyomegaly and micronuclei in proximal tubular epithelial cells (PTECs). We previously performed comprehensive gene profiling of alterations in promoter-region methylation and gene expression in PTECs of rats treated with OTA for 13 weeks. The OTA-specific gene profile was obtained by excluding genes showing expression changes similar to those upon treatment with 3-chloro-1,2-propanediol, a renal carcinogen not inducing karyomegaly. In this study, we validated the candidate genes using methylated DNA enrichment PCR and real-time RT-PCR, and identified Gen1, Anxa3, Cdkn1a, and Osm as genes showing OTA-specific epigenetic changes. These genes and related molecules were subjected to gene expression and immunohistochemical analyses in the PTECs of rats treated with OTA, other renal carcinogens, or non-carcinogenic renal toxicants for 4 or 13 weeks. Cdkn1a upregulation and increase of p21WAF1/CIP1+ karyomegalic PTECs were observed with OTA, matching the findings associated with micronucleus-inducing carcinogens. This suggested that the increase of p21WAF1/CIP1+ karyomegalic PTECs is linked to micronucleus formation, which in turn accelerates chromosomal instability. The upregulation of Cdkn1a-related genes with OTA suggests the acquisition of a senescence-associated secretory phenotype, which promotes the establishment of a carcinogenic environment. Meanwhile, OTA specifically caused a decrease of GEN1+ PTECs reflecting Gen1 downregulation and an increase of ANXA3+ PTECs reflecting Anxa3 upregulation, as well as Osm upregulation. OTA may efficiently disrupt pathways for repairing the DNA double-strand breaks that it itself causes, via Gen1 downregulation, and enhance cell proliferation through the upregulation of Anxa3 and Osm. This may exacerbate the chromosomal instability from the early stage of OTA-induced renal carcinogenesis before proliferative lesions form. OTA may cause renal carcinogenesis involving multiple epigenetic mechanisms.

Effects of Exercise-Induced Changes in Myokine Expression on the Tumor Microenvironment

In this narrative review, we summarize the direct and indirect effects that myokines have on the tumor microenvironment. We took studies of various cancer types and species into account. Systematic reviews and meta-analyses that matched the search terms were also considered. We searched databases for six months. As a narrative approach was chosen, no data was analyzed or reanalyzed. The goal of this narrative review is to create an overview on the topic to identify research gaps and answer the questions as to whether myokine expression may be relevant in cancer research in regard to the tumor microenvironment. Six commonly known myokines were chosen. We found strong links between the influence exercise has on interleukin-6, oncostatin M, secreted protein acidic and rich in cysteine, and irisin in the context of tumor progression and inhibition via interactions with the tumor microenvironment. It became clear that the effects of myokines on the tumor microenvironment can vary and contribute to disease progression or regression. Interactions among myokines and immune cells must also be considered and require further investigation. To date, no study has shown a clear connection, while multiple studies suggest further investigation of the topic, similar to the effects of exercise on myokine expression.

Potential involvement of oncostatin M in the immunosuppressive tumor immune microenvironment in hepatocellular carcinoma with vessels encapsulating tumor clusters

AIM

Vessels encapsulating tumor clusters (VETC) represents an adverse prognostic morphological feature of hepatocellular carcinoma (HCC), which is associated with an immunosuppressive tumor immune microenvironment (TIM). However, the underlying factors characterizing the TIM in HCC with a VETC pattern (VETC-positive HCC) remain uncertain. Oncostatin M (OSM), a pleiotropic cytokine of the interleukin-6 family, regulates various biological processes, including inflammation, proliferation, and invasiveness of tumor cells. We aimed to test a hypothesis that OSM is associated with the immunosuppressive TIM of VETC-positive HCC.

METHODS

A total of 397 consecutive HCC patients with curative-intent hepatectomy were included. OSM-positive cells and inflammatory cells including CD4-, CD8-, CD163-, and FOXP3-positive cells were immunohistochemically evaluated. We compared VETC-positive and VETC-negative HCCs in terms of the number of these cells.

RESULTS

We found the VETC pattern in 62 patients (15.6%). Our analysis revealed a significant decrease in the expression of arginase-1, a marker associated with mature hepatocyte differentiation, in VETC-positive HCC (p = 0.046). The number of tumor-infiltrating OSM-positive cells was significantly low in VETC-positive HCC (p = 0.0057). Notably, in VETC-positive HCC, the number of OSM-positive cells was not associated with vascular invasion, whereas in VETC-negative HCC, an increase in the number of OSM-positive cells was associated with vascular invasion (p = 0.042).

CONCLUSIONS

We identified an association between a decrease in OSM-positive cells and the VETC pattern. Additionally, our findings indicate that VETC-positive HCC is characterized by low hepatocyte differentiation and OSM-independent vascular invasion. These findings highlight the potential interaction between VETC-positive HCC cells and their TIM through the reduction of OSM-expressing cells.

Oxidative Stress and Redox-Dependent Pathways in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a primary liver tumor that accounts for 2% of all cancer-related deaths worldwide yearly. It can arise from cholangiocytes of biliary tracts, peribiliary glands, and possibly from progenitor cells or even hepatocytes. CCA is characterized by high chemoresistance, aggressiveness, and poor prognosis. Potentially curative surgical therapy is restricted to a small number of patients with early-stage disease (up to 35%). Accumulating evidence indicates that CCA is an oxidative stress-driven carcinoma resulting from chronic inflammation. Oxidative stress, due to enhanced reactive oxygen species (ROS) production and/or decreased antioxidants, has been recently suggested as a key factor in cholangiocyte oncogenesis through gene expression alterations and molecular damage. However, due to different experimental models and conditions, contradictory results regarding oxidative stress in cholangiocarcinoma have been reported. The role of ROS and antioxidants in cancer is controversial due to their context-dependent ability to stimulate tumorigenesis and support cancer cell proliferation or promote cell death. On these bases, the present narrative review is focused on illustrating the role of oxidative stress in cholangiocarcinoma and the main ROS-driven intracellular pathways. Heterogeneous data about antioxidant effects on cancer development are also discussed.

Correlation Between Oncostatin M and Acute Ischemic Stroke: A Case-Control Study

BACKGROUND

The expression of oncostatin M (OSM) has been studied in various diseases related to inflammatory response, but its implementation in acute ischemic stroke (AIS) remains to be explored.  Objective: The objective of this study is to assess the correlation between serum OSM expression and various aspects of AIS in a clinical setting.

MATERIALS AND METHOD

A single-centered case-control study was performed in the First Affiliate Hospital of Chongqing Medical University from October 2020 to March 2021. A total of 134 patients were enrolled in the AIS group and 34 healthy individuals were enrolled in the control group. Physical examinations were performed and venous blood samples were collected. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum OSM. Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, National Institutes of Health Stroke Scale (NIHSS) score, magnetic resonance imaging (MRI) scan, and modified Rankin scale (mRS) were used to assess the classification, etiology, severity, and prognosis of the AIS group. Assessments were done to analyze serum OSM expression based on sensitivity, etiology, severity, prognosis, and several risk factors of AIS. Regression models, correlation, and sensitivity tests were performed to explore the correlation of OSM expression with various aspects of AIS.

RESULTS

There was a statistically significant elevation of serum OSM expression in the AIS group (P<0.001). All AIS subgroups showed elevation in OSM level and statistically significant results were reflected in three subgroups. The area under the curve to differentiate AIS patients and control by serum OSM level was 0.747 (P<0.001), with the optimal cut-off value showing sensitivity at 58.82% and specificity at 75.37%. The elevation of serum OSM expression was proportional with severity, not proportional to the volume of infarct, and less elevated in the favorable outcome group. Serum OSM correlation with several risk factors of AIS was statistically significant in age, low-density lipoprotein, non-high-density lipoprotein, prothrombin time, and systolic blood pressure.

CONCLUSION

Serum OSM was expressed differently in correlation with various aspects of AIS. Our findings supported the initial hypothesis that OSM is correlated with various aspects of AIS in humans.

Identification of genes showing altered DNA methylation and gene expression in the renal proximal tubular cells of rats treated with ochratoxin A for 13 weeks

Ochratoxin A (OTA) is a mycotoxin that causes renal carcinogenicity following the induction of karyomegaly in proximal tubular cells after repeated administration to rats. Here, we performed gene profiling regarding altered DNA methylation and gene expression in the renal tubules focusing on the mechanism of OTA-induced carcinogenesis. For this purpose, OTA or 3-chloro-1,2-propanediol (3-MCPD), a renal carcinogen not inducing karyomegaly, was administered to rats for 13 weeks, and DNA methylation array and RNA sequencing analyses were performed on proximal tubular cells. Genes for which OTA altered the methylation status and gene expression level, after excluding genes showing similar expression changes by 3-MCPD, were subjected to confirmation analysis of the transcript level by real-time reverse-transcription PCR. Gene Ontology (GO)-based functional annotation analysis of validated genes revealed a cluster of hypermethylated and downregulated genes enriched under the GO term "mitochondrion," such as those associated with metabolic reprogramming in carcinogenic process (Clpx, Mrpl54, Mrps34, and Slc25a23). GO terms enriched for hypomethylated and upregulated genes included "response to arsenic-containing substance," represented by Cdkn1a involved in cell cycle arrest, and "positive regulation of IL-17 production," represented by Osm potentiating cell proliferation promotion. Other genes that did not cluster under any GO term included Lrrc14 involved in NF-κB-mediated inflammation, Gen1 linked to DNA repair, Has1 related to chromosomal aberration, and Anxa3 involved in tumor development and progression. In conclusion, a variety of genes engaged in carcinogenic processes were obtained by epigenetic gene profiling in rat renal tubular cells specific to OTA treatment for 13 weeks.

Regulation of tumor angiogenesis by the crosstalk between innate immunity and endothelial cells

Endothelial cells and immune cells are major regulators of cancer progression and prognosis. Endothelial cell proliferation and angiogenesis are required for providing nutrients and oxygen to the nascent tumor and infiltration of immune cells to the tumor is dependent on endothelial cell activation. Myeloid cells and innate lymphocytes have an important role in shaping the tumor microenvironment by crosstalking with cancer cells and structural cells, including endothelial cells. Innate immune cells can modulate the activation and functions of tumor endothelial cells, and, in turn, endothelial cell expression of adhesion molecules can affect immune cell extravasation. However, the mechanisms underlying this bidirectional crosstalk are not fully understood. In this review, we will provide an overview of the current knowledge on the pathways regulating the crosstalk between innate immune cells and endothelial cells during tumor progression and discuss their potential contribution to the development of novel anti-tumor therapeutic approaches.

Oncostatin M Contributes to Airway Epithelial Cell Dysfunction in Chronic Rhinosinusitis with Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a typical type-2 inflammation involving several cytokines and is associated with epithelial cell dysfunction. Oncostatin M (OSM) (belonging to the interleukin(IL)-6 family) could be a key driver of epithelial barrier dysfunction. Therefore, we investigated the presence of OSM and IL-6 and the expression pattern of tight junctions (TJs) in the nasal tissue of CRSwNP patients and controls using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Then, their potential role in the epithelial barrier was evaluated in vitro in 27 different primary cultures of human nasal epithelial cells (HNECs) by measuring TJ expression and transepithelial electric resistance (TEER) with or without OSM or IL-6 (1, 10, and 100 ng/mL). The effect on ciliary beating efficiency was evaluated by high-speed videomicroscopy and on repair mechanisms with a wound healing model with or without OSM. OSM and IL-6 were both overexpressed, and TJ (ZO-1 and occludin) expression was decreased in the nasal polyps compared to the control mucosa. OSM (100 ng/mL) but not IL-6 induced a significant decrease in TJ expression, TEER, and ciliary beating efficiency in HNECs. After 24 h, the wound repair rate was significantly higher in OSM-stimulated HNECs at 100 ng/mL. These results suggest that OSM could become a new target for monoclonal antibodies.