PLZF expression during colorectal cancer development and in normal colorectal mucosa according to body size, as marker of colorectal cancer risk

Immunometabolic Changes Following Gastric Bypass and Sleeve Gastrectomy: A Comparative Study

BACKGROUND

Immunometabolism is the interaction between immune system and nutrient metabolism. Severe obesity is considered a state of meta-inflammation associated with obesity that influences the development of chronic-degenerative diseases.

OBJECTIVE

We aimed to establish the immunometabolic differences in bariatric patients and to determine whether cellular immunity is associated with metabolic changes.

METHODOLOGY

We conducted an observational study in patients who underwent laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB). We explored the differences in the immunometabolic profile before and after surgery in the study group, by surgical technique, and we evaluated the changes in immunological variables as a function of metabolic variables with correlation analysis.

RESULTS

The follow-up rate was 88.7%. After the intervention, there were changes in cellular immunity, with a decrease in effector T lymphocytes (CD8+CD28-) and an increase in B lymphocytes, memory helper T cells, and cytotoxic T lymphocytes. LSG resulted in a greater decrease in (CD4+CD62-) T lymphocytes compared with LRYGB. Patients who underwent surgery with LRYGB presented greater clinical and metabolic improvements, as well as improvement of obesity-associated medical problems. Women who underwent LRYGB showed a greater reduction in fat-free mass compared with women who underwent LSG.

CONCLUSION

Bariatric surgery, mainly LRYGB, leads to immunometabolic changes and improves associated medical problems.

Natural Killer Cell Dysfunction in Obese Patients with Breast Cancer: A Review of a Triad and Its Implications

Natural killer cells (NK cells) are a crucial constituent of the innate immune system as they mediate immunity against viruses, bacteria, parasites, and most importantly, tumor cells. The exact mechanism of how the innate immune system and specifically NK cells interact with cancer cells is complex and is yet to be understood. Several factors that constitute the tumor microenvironment (TME) such as hypoxia and TGF-β are believed to play a role in the complex physiological reaction of NK cells to tumor cells. On the other hand, several risk factors are implicated in the development and progression of breast cancer, most importantly: obesity. Cytokines released from adipose tissue such as adipokines, leptin, and resistin, among others, are also believed to facilitate tumor progression. In this study, we aimed to build a triad of breast cancer, obesity, and NK cell dysfunction to elucidate a link between these pillars on a cellular level. Directing efforts towards solidifying the link between these factors will help in designing a targeted immunotherapy with a low side-effect profile that can revolutionize breast cancer treatment and improve survival in obese patients.

PLZF and PLZF-MAPK10 can predict the prognosis of postoperative patients with hepatocellular carcinoma

OBJECTIVE

The current study aimed to explore the expression level of promyelocytic leukaemia zinc finger (PLZF) in hepatocellular carcinoma tissues and to investigate the value of detecting the expression levels of PLZF and mitogen-activated protein kinase 10 (MAPK10) on predicting prognosis.

METHODS

This study selected data from 53 patients with HCC who had undergone hepatectomy in our hospital. The expressions of PLZF and MAPK10 in tumor tissues and normal tissues were compared and related clinical factors were analyzed. The clinical data including patient's gender, age, hepatitis B virus infection (HBV), alpha-fetoprotein levels (AFP), tumor size, TNM stage (AJCC), cirrhosis, portal vein tumor thrombus (PVTT), bile duct tumor thrombus (BDTT), and OS (Overall survival) was collected.

RESULTS

We found that PLZF expression was significantly down-regulated in HCC samples compared with that in adjacent non-tumor tissues (P=0.001). The expression level of PLZF was correlated with patients' gender (P=0.046), tumor stage (P=0.039), and OS (P=0.015). Moreover, the expression level of PLZF-MAPK10 (P-M protein) was correlated with gender (P=0.000) and tumor stage (P=0.045). Multivariate analyses showed that microsatellite nodules, PLZF, and P-M protein were independent risk factors of HCC prognosis. Postoperative patients with a normal expression level of PLZF and MAPK10 have a longer overall survival than those with abnormal levels (P=0.039).

CONCLUSION

PLZF expression was significantly down-regulated in HCC tissues and itself and PLZF-MAPK10 were both independent prognostic factors for the OS of patients with HCC.

Extracellular vesicle derived miR-544 downregulates expression of tumor suppressor promyelocytic leukemia zinc finger resulting in increased peritoneal metastasis in gastric cancer

Peritoneal metastasis (PM) is the main cause of poor prognosis in patients with advanced gastric cancer (GC). Increasing evidence has suggested that cancer-associated EVs in body fluids may assist in the diagnosis and treatment of GC. Here, we investigated the role of GC-derived EVs in PM development. Our results demonstrate that expression of the tumor suppressor promyelocytic leukemia zinc finger (PLZF) is decreased in GC tissues and PM lesions from GC patients. PLZF suppression promoted migration and invasion of peritoneal mesothelial HMrSV5 cells, while PLZF overexpression suppressed HMrSV5 cell migration and invasion. Microarray analysis revealed significantly upregulated expression of several miRNAs in EVs isolated from GC patients with PM, including miR-544. The increased miR-544 expression was confirmed in GC tissues and PM-derived EVs. Transfection with miR-544 reduced PLZF expression in HMrSV5 cells, while miR-544 inhibition increased PLZF expression. Incubation of GC cells with peritoneal mesothelial HMrSV5 cells showed that miR-544 could be transferred from GC-derived EVs to peritoneal cells, where it suppressed the PLZF expression. These findings indicate that EV-mediated transfer of miR-544 decreases the PLZF expression in PM lesions, which suggests miR-544 could potentially serve as a diagnostic biomarker and therapeutic target for treatment of GC patients.

Characterization of natural killer cells in colorectal tumor tissue of rats fed a control diet or a high-fat diet

BACKGROUND

Obesity is a major public health problem with an increasing prevalence reaching pandemic levels. The incidence and mortality for colorectal cancer is augmented in overweight and obese individuals. Previous studies demonstrated an impaired number, phenotype and functionality of natural killer (NK) cells under obese conditions. So far, the influence of obesity on NK cells in colorectal cancer tissue remained unclear. Therefore, the aim of the study was to investigate the occurrence and localization of NK cells in colorectal tumors of normal weight and diet-induced obese rats.

METHODS

Wistar rats were fed a normal-fat diet (control) or a high-fat diet (HFD) to induce obesity. In half of the experimental groups azoxymethane (AOM) was injected to induce colorectal cancer. Tumors in colon and rectum were histopathologically classified in adenomas and adenocarcinomas and immunohistologically stained with the rat NK cell marker CD161. Occurrence and localization of NK cells were analyzed and quantified in the tunica mucosa and tunica submucosa of colorectal adenomas and the tunica submucosa of colorectal adenocarcinomas.

RESULTS

NK cells are localized in the tunica mucosa and the tunica submucosa of colorectal tumors with NK cell accumulations as follicle-like aggregates especially in regions of the lamina muscularis mucosae and the lamina propria mucosae of the tunica mucosa as well as in regions of the tunica submucosa adjacent to the lamina muscularis mucosae. Although not statistically significant, the CD161 staining was clearly reduced in the tunica mucosa of colorectal tumors of rats fed a HFD compared to rats fed a control diet. Moreover, the CD161 staining in the tunica mucosa was positively correlated with the final body weight of AOM-treated rats independent of the supplied diet.

DISCUSSION

For the first time, these results provide information about the localization and quantity of NK cells in colorectal tumor tissue of rats fed a control diet or high-fat diet. The slight reduction of NK cell number in colorectal tissue of rats fed a high-fat diet may contribute to an impaired tumor defense and the increased colorectal tumor outcome in diet-induced obese rats.

Obesity-Associated Alterations of Natural Killer Cells and Immunosurveillance of Cancer

Obesity is accompanied by a systemic chronic low-grade inflammation as well as dysfunctions of several innate and adaptive immune cells. Recent findings emphasize an impaired functionality and phenotype of natural killer (NK) cells under obese conditions. This review provides a detailed overview on research related to overweight and obesity with a particular focus on NK cells. We discuss obesity-associated alterations in subsets, distribution, phenotype, cytotoxicity, cytokine secretion, and signaling cascades of NK cells investigated in vitro as well as in animal and human studies. In addition, we provide recent insights into the effects of physical activity and obesity-associated nutritional factors as well as the reduction of body weight and fat mass on NK cell functions of obese individuals. Finally, we highlight the impact of impaired NK cell physiology on obesity-associated diseases, focusing on the elevated susceptibility for viral infections and increased risk for cancer development and impaired treatment response.

Promyelocytic leukemia zinc finger triggers ATP-binding cassette subfamily E member 1-mediated growth inhibition in breast cancer cells

The promyelocytic leukemia zinc finger (PLZF) protein is a transcription factor that is involved in a number of biological processes, including those regulating cellular growth; however, little is known regarding how it achieves its inhibitory effect in different cell and tissue types. It has previously been demonstrated that PLZF expression levels become diminished during the oncogenic transformation of certain tissue types and thus, may serve as a hallmark for tumor aggressiveness. To examine this in breast cancer, survival curves from available oncology databases were analyzed and demonstrated that PLZF expression was positively associated with increased survival in patients with breast cancer. The mRNA and protein levels of PLZF were also revealed to be associated with the tumorigenicity of four breast cancer cell lines. Since ATP-binding cassette subfamily E member 1 (ABCE1), also known as RNase L inhibitor, has been determined to be a target gene of PLZF, the present study also investigated whether the tumor suppressive effect of PLZF was associated with ABCE1 expression. PLZF was revealed to downregulate the expression of ABCE1 in vitro, which relieved the inhibitory effect of ABCE1 on the ribonuclease L enzyme. Finally, it was concluded that PLZF expression caused an ABCE1-mediated increase in cellular cytotoxicity, as demonstrated by a reduction in the proliferation rate of breast cancer cell lines. The results of the present study are important for understanding how PLZF exerts its final inhibitory actions in breast cancer cells, and potentially in other solid tumors, through the modulation of immunological pathways.

Aberrantly Expressed Genes and miRNAs in Slow Transit Constipation Based on RNA-Seq Analysis

Background

This study aims to identify the key genes and miRNAs in slow transit constipation (STC).

Methods

MRNA and miRNA expression profiling were obtained. Differentially expressed genes (DEGs) and miRNAs were identified followed by the regulatory network construction. Functional annotation analysis and protein-protein interaction (PPI) network were conducted. The electronic validation was performed.

Results

Hsa-miR-2116-3p, hsa-miR-3622a-5p, hsa-miR-424-5p, and hsa-miR-1273-3p covered most DEGs. HLA-DRB1, HLA-DRB5, C3, and ICAM were significantly involved in staphylococcus aureus infection. The PPI network generated several hub proteins including ZBTB16, FBN1, CCNF, and CDK1. Electronic validation of HLA-DRB1, PTGDR, MKI67, BIRC5, CCNF, and CDK1 was consistent with the RNA-sequencing analysis.

Conclusion

Our study might be helpful in understanding the pathology of STC at the molecular level.

Functional analysis of Cullin 3 E3 ligases in tumorigenesis

Cullin 3-RING ligases (CRL3) play pivotal roles in the regulation of various physiological and pathological processes, including neoplastic events. The substrate adaptors of CRL3 typically contain a BTB domain that mediates the interaction between Cullin 3 and target substrates to promote their ubiquitination and subsequent degradation. The biological implications of CRL3 adaptor proteins have been well described where they have been found to play a role as either an oncogene, tumor suppressor, or can mediate either of these effects in a context-dependent manner. Among the extensively studied CRL3-based E3 ligases, the role of the adaptor protein SPOP (speckle type BTB/POZ protein) in tumorigenesis appears to be tissue or cellular context dependent. Specifically, SPOP acts as a tumor suppressor via destabilizing downstream oncoproteins in many malignancies, especially in prostate cancer. However, SPOP has largely an oncogenic role in kidney cancer. Keap1, another well-characterized CRL3 adaptor protein, likely serves as a tumor suppressor within diverse malignancies, mainly due to its specific turnover of its downstream oncogenic substrate, NRF2 (nuclear factor erythroid 2-related factor 2). In accordance with the physiological role the various CRL3 adaptors exhibit, several pharmacological agents have been developed to disrupt its E3 ligase activity, therefore blocking its potential oncogenic activity to mitigate tumorigenesis.

Role of PLZF as a tumor suppressor in prostate cancer

The promyelocytic leukemia zinc finger (PLZF), also known as ZBTB16 (Zinc Finger And BTB Domain Containing 16), is a transcription factor involved in the regulation of diverse biological processes, including cell proliferation, differentiation, organ development, stem cell maintenance and innate immune cell development. A number of recent studies have now implicated PLZF in cancer progression as a tumor suppressor. However, in certain cancer types, PLZF may function as an oncoprotein. Here, we summarize our current knowledge on the role of PLZF in various cancer types, in particular prostate cancer, including its deregulation, genomic alterations and potential functions in prostate cancer progression.

Correlation of tumor-associated macrophages and NK cells with bladder cancer size and T stage in patients with solitary low-grade urothelial carcinoma

OBJECTIVE

The aim of the present study was to correlate the level of tumor-infiltrating immune cells with bladder cancer size and T category in patients with solitary low-grade non-muscle invasive bladder cancer (NMIBC).

PATIENTS AND METHODS

Between 1996 and 2006, 115 patients with solitary low-grade NMIBC after transurethral resection of the bladder without adjuvant therapy were retrospectively identified from the institutional database. Tumor specimens were retrieved and tissue microarrays were constructed. Immunhistochemical staining for tumor-infiltrating immune cells with anti-CD3, CD4, CD8, CD20, CD56, CD68, and granzyme B (Gr B) was performed.

RESULTS

Immune cells were predominantly observed within the cancer stroma. Statistically significant higher levels of CD56 cells in small tumors and CD68 cells in T1 tumors (p = 0.0310, 0.0151, respectively) were established.

CONCLUSION

The current study propose a possible correlation of CD56+ and CD68+ cells with bladder cancer size and stage in patients with solitary low-grade NMIBC.