High expression of interleukin-11 is an independent indicator of poor prognosis in clear-cell renal cell carcinoma

The role of interleukin-6 family cytokines in cancer cachexia

Cachexia is a wasting syndrome that manifests in more than half of all cancer patients. Cancer-associated cachexia negatively influences the survival of patients and their quality of life. It is characterized by a rapid loss of adipose and skeletal muscle tissues, which is partly mediated by inflammatory cytokines. Here, we explored the crucial roles of interleukin-6 (IL-6) family cytokines, including IL-6, leukemia inhibitory factor, and oncostatin M, in the development of cancer cachexia. These cytokines have been shown to exacerbate cachexia by promoting the wasting of adipose and muscle tissues, activating mechanisms that enhance lipolysis and proteolysis. Overlapping effects of the IL-6 family cytokines depend on janus kinase/signal transducer and activator of transcription 3 signaling. We argue that the blockade of these cytokine pathways individually may fail due to redundancy and future therapeutic approaches should target common downstream elements to yield effective clinical outcomes.

Exploring the role of interleukin 11 in cancer progression, patient survival, and therapeutic insights

BACKGROUND

The Interleukin (IL)-11 gene, which is one of the members of the cytokine family, has an oncogenic role in some cancers. The main goal of this study is to analyze IL-11 expression level in 14 prevalent cancers and highlights its role in patients' survival, drug resistance, and sensitivities. Also, an association of this gene with metastasis and inflammation pathways has been investigated.

METHODS AND RESULTS

Using the cancer genome atlas (TCGA) data, the level of IL-11 expression and its role in prognosis and survival rate were evaluated in 13 common cancers. Then, confirming the obtained in-silico outcomes, the relative expression level of this gene in colorectal cancer (CRC) samples and their adjusted tissues were assayed by the RT-qPCR method. Furthermore, to examine the association between IL-11 expression and drug resistance and sensitivity, PharmacoGX data was applied. The co-expression network was used to recognize the pathways in which IL-11 was involved. The results from the TCGA dataset indicated that the expression level of IL-11 increased significantly in 13 prevalence cancers compared to the control groups. Interestingly, this enhanced expression level is associated with a high rate of mortality in patients with bladder, stomach, colorectal, and endometrial cancers. Also, the co-expression network analysis showed a strong correlation between IL-11 and the genes of metastasis pathway and the genes related to the inflammation process. Finally, regarding drug sensitivity, IL-11 expression level can be introduced as a remarkable biomarker for cancer detection due to area under curve (AUC).

CONCLUSION

Altered expression of the IL-11 gene is observed in 13 common cancers and is associated with prognosis and mortality rate in patients. Moreover, this gene can be considered a prognostic biomarker in different types of cancer, such as CRC.

Interleukin-11/IL-11 Receptor Promotes Glioblastoma Cell Proliferation, Epithelial-Mesenchymal Transition, and Invasion

Glioblastoma is highly proliferative and invasive. However, the regulatory cytokine networks that promote glioblastoma cell proliferation and invasion into other areas of the brain are not fully defined. In the present study, we define a critical role for the IL-11/IL-11Rα signalling axis in glioblastoma proliferation, epithelial to mesenchymal transition, and invasion. We identified enhanced IL-11/IL-11Rα expression correlated with reduced overall survival in glioblastoma patients using TCGA datasets. Proteomic analysis of glioblastoma cell lines overexpressing IL-11Rα displayed a proteome that favoured enhanced proliferation and invasion. These cells also displayed greater proliferation and migration, while the knockdown of IL-11Rα reversed these tumourigenic characteristics. In addition, these IL-11Rα overexpressing cells displayed enhanced invasion in transwell invasion assays and in 3D spheroid invasion assays, while knockdown of IL-11Rα resulted in reduced invasion. Furthermore, IL-11Rα-overexpressing cells displayed a more mesenchymal-like phenotype compared to parental cells and expressed greater levels of the mesenchymal marker Vimentin. Overall, our study identified that the IL-11/IL-11Rα pathway promotes glioblastoma cell proliferation, EMT, and invasion.

Pharmacologic inhibition of IL11/STAT3 signaling increases MHC-I expression and T cell infiltration

BACKGROUND

Recent studies have discovered an emerging role of IL11 in various colitis-associated cancers, suggesting that IL11 mainly promotes tumor cell survival and proliferation in regulating tumorigenesis. Herein we aimed to reveal a novel function of IL-11 through STAT3 signaling in regulating tumor immune evasion.

METHODS

AOM/DSS model in Il11^-/- and Apc^min/+/Il11^-/- mice were used to detect tumor growth and CD8⁺ T infiltration. STAT1/3 phosphorylation and MHC-I, CXCL9, H2-K1 and H2-D1 expression were detected in MC38 cells and intestine organoids treated with/without recombinant IL11 to explore effect of IL11/STAT3 signaling, with IL11 mutein used to competitively inhibit IL11 and rescue inhibited STAT1 activation. Correlation between IL11 and CD8⁺ T infiltration was analyzed using TIMER2.0 website. IL11 expression and survival prognosis was analyzed in clinical data of patient cohort from Nanfang Hospital.

RESULTS

IL11 is highly expressed in CRC and indicates unfavorable prognosis. IL11 knockout increased CD8⁺ T cell infiltration and reduced intestinal and colon formation. Tumors were significantly suppressed while MHC-I and CXCL9 expression for CD8⁺ T infiltration were remarkably increased in the tumor tissues of Apc^min/+/Il11^-/- mice or Il11^-/- mice induced by AOM/DSS. IL11/STAT3 signaling downregulated MHC-I and CXCL9 by inhibiting IFNγ-induced STAT1 phosphorylation. IL11 mutein competitively inhibit IL11 to upregulate CXCL9 and MHC-I in tumor and attenuated tumor growth.

CONCLUSIONS

This study ascribes for a new immunomodulatory role for IL11 during tumor development that is amenable to anti-cytokine based therapy of colon cancer.

Gene Expression Changes in Cytokine and Chemokine Receptors in Association with Melanoma Liver Metastasis

Cytokines and chemokines (chemotactic cytokines) are soluble extracellular proteins that bind to specific receptors and play an integral role in the cell-to-cell signaling network. In addition, they can promote the homing of cancer cells into different organs. We investigated the potential relationship between human hepatic sinusoidal endothelial cells (HHSECs) and several melanoma cell lines for the expression of chemokine and cytokine ligands and receptor expression during the invasion of melanoma cells. In order to identify differences in gene expression related to invasion, we selected invasive and non-invasive subpopulations of cells after co-culturing with HHSECs and identified the gene expression patterns of 88 chemokine/cytokine receptors in all cell lines. Cell lines with stable invasiveness and cell lines with increased invasiveness displayed distinct profiles of receptor genes. Cell lines with increased invasive capacity after culturing with conditioned medium showed a set of receptor genes (CXCR1, IL1RL1, IL1RN, IL3RA, IL8RA, IL11RA, IL15RA, IL17RC, and IL17RD) with significantly different expressions. It is very important to emphasize that we detected significantly higher IL11RA gene expression in primary melanoma tissues with liver metastasis as well, compared to those without metastasis. In addition, we assessed protein expression in endothelial cells before and after co-culturing them with melanoma cell lines by applying chemokine and cytokine proteome arrays. This analysis revealed 15 differentially expressed proteins (including CD31, VCAM-1, ANGPT2, CXCL8, and CCL20) in the hepatic endothelial cells after co-culture with melanoma cells. Our results clearly indicate the interaction between liver endothelial and melanoma cells. Furthermore, we assume that overexpression of the IL11RA gene may play a key role in organ-specific metastasis of primary melanoma cells to the liver.

OShnscc: a novel user-friendly online survival analysis tool for head and neck squamous cell carcinoma based on RNA expression profiles and long-term survival information

Head and neck squamous cell carcinoma (HNSCC), as the most common type (>90%) of head and neck cancer, includes various epithelial malignancies that arise in the nasal cavity, oral cavity, pharynx, and larynx. In 2020, approximately 878 ‍ 000 new cases and 444 000 deaths linked to HNSCC occurred worldwide (Sung et al., 2021). Due to the associated frequent recurrence and metastasis, HNSCC patients have poor prognosis with a five-year survival rate of 40%-50% (Jou and Hess, 2017). Therefore, novel prognostic biomarkers need to be developed to identify high-risk HNSCC patients and improve their disease outcomes.

Immunogenomic Analyses of the Prognostic Predictive Model for Patients With Renal Cancer

Background

Renal cell carcinoma (RCC) is associated with poor prognostic outcomes. The current stratifying system does not predict prognostic outcomes and therapeutic benefits precisely for RCC patients. Here, we aim to construct an immune prognostic predictive model to assist clinician to predict RCC prognosis.

Methods

Herein, an immune prognostic signature was developed, and its predictive ability was confirmed in the kidney renal clear cell carcinoma (KIRC) cohorts based on The Cancer Genome Atlas (TCGA) dataset. Several immunogenomic analyses were conducted to investigate the correlations between immune risk scores and immune cell infiltrations, immune checkpoints, cancer genotypes, tumor mutational burden, and responses to chemotherapy and immunotherapy.

Results

The immune prognostic signature contained 14 immune-associated genes and was found to be an independent prognostic factor for KIRC. Furthermore, the immune risk score was established as a novel marker for predicting the overall survival outcomes for RCC. The risk score was correlated with some significant immunophenotypic factors, including T cell infiltration, antitumor immunity, antitumor response, oncogenic pathways, and immunotherapeutic and chemotherapeutic response.

Conclusions

The immune prognostic, predictive model can be effectively and efficiently used in the prediction of survival outcomes and immunotherapeutic responses of RCC patients.

What Mediates Fibrosis in the Tumor Microenvironment of Clear Renal Cell Carcinoma

Previous studies have demonstrated that direct targeting of interstitial cancer-associated fibroblasts (CAF) and tumor fibrosis alone seemed to be an unpromising treatment option for malignant tumors. Therefore, it is necessary to further explore the mechanism of the influence of collagen and tumor fibrosis on the biological behavior of malignant tumors. The current study aimed to explore the effect of intratumor fibrosis on the prognosis of renal clear cell carcinoma (ccRCC) and its mechanism. With the bioinformatic analysis of The Cancer Genome Atlas (TCGA) database (n = 537), the study showed that high Collagen type I α 1 (COL1A1) mRNA expression indicated the poor prognosis of ccRCC patients compared with low expression ones. We further used the Two-photon-excited fluorescence (TPEF)/second harmonic generation (SHG) microscopy to determine the intratumor fibrosis of 68 patients with surgical resection of ccRCC and confirmed that a high fibrosis level in the tumor was associated with a poor prognosis compared with patients with low expression (Progression-Free Survival: p = 0.030). We further measured the protein chips of 640 cytokines in ccRCC specimens and found that several cytokines, including prolactin (PRL), were associated with the degree of fibrosis in the tumor, as confirmed by the prolactin receptor (PRLR) immunohistochemical method. In addition, the study showed that PRLR expression decreased significantly in the ccRCC compared with adjacent normal tissue (p < 0.05). Our research shows that low expression of PRLR predicted the poor survival of the patient. We used the Cell Counting Kit-8 experiment, the transwell and the plate clone formation assay to evaluate the role of PRL in the 7860 and the ACHN cell lines. We found that PRL promoted ccRCC cell proliferation and migration. JAK-STAT3 activation was found in the high prolactin expression group by mass spectrum analysis. This study delineated the fibrosis-based tumor microenvironment characteristics of ccRCC. PRL/PRLR may be involved in the fibrosis process and are essential prognostic risk factors for ccRCC.

Clinical Significance and Immunologic Landscape of a Five-IL(R)-Based Signature in Lung Adenocarcinoma

Interleukins (ILs) and interleukin receptors (ILRs) play important role in the antitumor immune response. However, the expression signature and clinical characteristics of the IL(R) family in lung adenocarcinoma (LUAD) remains unclear. The main purpose of this study was to explore the expression profile of IL(R) family genes and construct an IL(R)-based prognostic signature in LUAD. Five public datasets of 1,312 patients with LUAD were enrolled in this study. Samples from The Cancer Genome Atlas (TCGA) were used as the training set, and samples from the other four cohorts extracted from Gene Expression Omnibus (GEO) database were used as the validation set. Additionally, the profile of IL(R) family signature was explored, and the association between this signature and immunotherapy response was also analyzed. Meanwhile, the prognostic value was compared between this IL(R)-based signature and different immunotherapy markers. A signature based on five identified IL(R)s (IL7R, IL5RA, IL20RB, IL11, IL22RA1) was constructed using the TCGA dataset through univariate/multivariable Cox proportional hazards regression and least absolute shrinkage and selection operator (LASSO) Cox analysis. These cases with LUAD were stratified into high- and low-risk group according to the risk score. This signature showed a strong prognostic ability, which was verified by the five independent cohorts and clinical subtypes. The IL(R)-based models presented unique characteristics in terms of immune cell infiltration and immune inflammation profile in tumor microenvironment (TME). Biological pathway analysis confirmed that high-risk patients showed significant T- and B-cell immunosuppression and rapid tumor cell proliferation. More importantly, we researched the relationship between this IL(R)-based signature and immune checkpoints, tumor mutation burden (TMB), tumor purity and ploidy, and tumor immune dysfunction and exclusion (TIDE) score, which confirmed that this signature gave the best prognostic value. We first provided a robust prognostic IL(R)-based signature, which had the potential as a predictor for immunotherapy response to realize individualized treatment of LUAD.

The HIF target MAFF promotes tumor invasion and metastasis through IL11 and STAT3 signaling

Hypoxia plays a critical role in tumor progression including invasion and metastasis. To determine critical genes regulated by hypoxia that promote invasion and metastasis, we screen fifty hypoxia inducible genes for their effects on invasion. In this study, we identify v-maf musculoaponeurotic fibrosarcoma oncogene homolog F (MAFF) as a potent regulator of tumor invasion without affecting cell viability. MAFF expression is elevated in metastatic breast cancer patients and is specifically correlated with hypoxic tumors. Combined ChIP- and RNA-sequencing identifies IL11 as a direct transcriptional target of the heterodimer between MAFF and BACH1, which leads to activation of STAT3 signaling. Inhibition of IL11 results in similar levels of metastatic suppression as inhibition of MAFF. This study demonstrates the oncogenic role of MAFF as an activator of the IL11/STAT3 pathways in breast cancer.

Hypoxia plays a critical role in tumor progression including invasion and metastasis. Here, the authors screened several hypoxia inducible genes and identified the oncogenic role of MAFF in breast cancer metastasis and that it activates IL11/STAT3 pathway.

miR-204-5p regulates cell proliferation, invasion, and apoptosis by targeting IL-11 in esophageal squamous cell carcinoma

Esophageal cancer (EC) is the world's eighth most common malignant neoplasm and is ranked as the sixth leading cause of death related to cancer. Aberrant microRNA (miRNA) expression has been reported to be associated with esophageal squamous cell carcinoma. However, the molecular mechanism of miR-204-5p in esophageal squamous cell carcinoma (ESCC) is not clear. Therefore, the aim of this study was to investigate the potential role of miR-204-5p in ESCC. In the present study, we found that miR-204-5p could affect ESCC proliferation, invasion, apoptosis, and cell cycle in cell and mouse models. A dual-luciferase reporter assay showed that miR-204-5p expression was negatively correlated with interleukin-11 (IL-11) expression. IL-11 overexpression reversed the suppressive effects of miR-204-5p in the cell lines. These results indicated that miR-204-5p functions as a tumor suppressor by directly targeting IL-11 in ESCC.

Increased interleukin-11 levels in thoracic aorta and plasma from patients with acute thoracic aortic dissection

BACKGROUND

Interleukin (IL) 11 is closely related to tumor and hematological system diseases. Recent studies have demonstrated that IL-11 also participates in cardiovascular diseases, including ischemia-reperfusion mediated heart injury and acute myocardial infarction. This study aimed to investigate whether IL-11 is involved in acute thoracic aortic dissection (TAD).

METHODS

Aortic tissue samples from normal donors and acute TAD patients were collected, and the expression of IL-11 in all aortic tissue was analyzed. In addition, blood samples from patients with chest pain were collected and divided into a non-AD (NAD) group and a TAD group according to the results of computed tomography angiography of the thoracic aorta. The plasma IL-11, IL-17 and interferon (IFN) γ in all blood samples were measured.

RESULTS

Compared with aortic tissue of normal controls, IL-11 was significantly increased in aortic tissue of acute TAD patients, especially in the torn section. The IL-11 was derived from aorta macrophages in TAD. In addition, the plasma IL-11, IL-17 and IFN-γ were significantly higher in acute TAD patients than in NAD patients, and the correlation analysis showed that IL-11 levels were positively correlated with levels of IFN-γ, IL-17, glucose, systolic blood pressure, diastolic blood pressure, white blood cells, C-reactive proteins and D-dimers. Binary logistic regression analyses showed that elevated IL11 in patients who may have diagnostic value of TAD, but less that D-dimer.

CONCLUSION

IL-11 was increased in thoracic aorta and plasma of TAD patients and may be a promising biomarker for diagnosis in patients with TAD.

IL-6 family cytokines: Key inflammatory mediators as biomarkers and potential therapeutic targets

IL-6 is a critical cytokine in acute phase response and involved in the pathogenesis of several chronic inflammatory diseases including cancer. Studies have highlighted that levels of IL-6 and its family members can be useful for diagnosis, prognosis of relapse-free survival and recurrence. IL-6 family cytokines have been identified as cancer biomarkers through screening of inflammatory mediators in different fluids including saliva, serum, and bronchoalveolar lavage fluid (BALF). IL-6 can be modulated by chemopreventive drugs, small molecules, monoclonal antibodies and immune checkpoint inhibitors. Unveiling the different sources of IL-6, the interaction between IL-6 and its cellular targets, the IL-6-dependent tumor resistance mechanisms, and the identification of novel regulators of IL-6 are some of the highly complex topics included in this review and their understanding could aid cancer biomarkers and therapy development.

C-met inhibition blocks bone metastasis development induced by renal cancer stem cells

Cancer stem cells (CSCs) are key players in bone metastasis. In some renal tumors CSCs overexpress the HGF receptor c-MET, speculating that c-MET targeting could lead to bone metastasis inhibition. To address this hypothesis we isolated renal CD105+/CD24−CSCs, expressing c-MET receptor from a primary renal carcinoma. Then, to study their ability to metastasize to bone, we injected renal CSCs in NOD/SCID mice implanted with a human bone and we tested the effect of a c-MET inhibitor (JNJ-38877605) on bone metastasis development. JNJ-38877605 inhibited the formation of metastases at bone implant site. We showed that JNJ-38877605 inhibited the activation of osteoclasts induced by RCC stem cells and it stimulated osteoblast activity, finally resulting in a reduction of bone turnover consistent with the inhibition of bone metastases. We measured the circulating levels of osteotropic factors induced by RCC stem cells in the sera of mice treated with c-Met inhibitor, showing that IL-11 and CCL20 were reduced in mice treated with JNJ-38877605, strongly supporting the involvement of c-MET in the regulation of this process. To address the clinical relevance of c-MET upregulation during tumor progression, we analysed c-MET in renal cancer patients detecting an increased expression in the bone metastatic lesions by IHC. Then, we dosed CCL20 serum levels resulting significantly increased in patients with bone metastases compared to non-metastatic ones. Collectively, our data highlight the importance of the c-MET pathway in the pathogenesis of bone metastases induced by RCC stem cells in mice and humans.

MicroRNA-124a inhibits cell proliferation and migration in liver cancer by regulating interleukin-11

Liver cancer is the sixth most common malignant tumour and ranks in the top three cancers with regard to mortality due to metastasis and postsurgical recurrence. It is significant to understand the mechanisms underlying liver cancer for diagnosis and treatment. Cumulative evidence suggests that the abnormal regulation of microRNAs (miRNAs/miRs) may contribute to the development and metastasis of cancer. miR‑124a acts as a tumour suppressor in osteosarcoma, endometrial carcinoma, prostate cancer, and glioblastoma. However, the effects of miR‑124a in liver cancer and its biological mechanism are not fully understood. It has been demonstrated that miR‑124a is downregulated and interleukin (IL)‑11 is upregulated in the liver cancer tissues. In the present study, miR‑124a upregulation inhibited cell proliferation, migration and promoted cell apoptosis. Through a dual‑luciferase reporter assay, it was verified that IL‑11 is a direct target of miR‑124a. Furthermore, the overexpression of miR‑124a repressed the secretion of IL‑11 from hepatoma cells. Finally, it was identified that mimics of miR‑124a increased the expression of tissue inhibitor of matrix metalloproteinase‑2 (TIMP‑2) and Caspase‑3 and decreased the expression levels of matrix metalloproteinase 2 (MMP2), MMP9, B‑cell lymphoma 2, signal transducer and activator of transcription 3 (STAT3), and phosphorylated‑STAT3. In conclusion, the results indicated that miR‑124a has an important role as a tumour suppressor gene by targeting IL‑11. These findings may provide novel insights for clinical treatments to prevent the development of liver cancer.

KRT8 upregulation promotes tumor metastasis and is predictive of a poor prognosis in clear cell renal cell carcinoma

Keratin 8 (KRT8) plays an essential role in the development and metastasis of multiple human cancers. However, its role in clear cell renal cell carcinoma (ccRCC) remains unexplored. Here, we investigated the expression pattern, clinical significance, and function of KRT8 in ccRCC. KRT8 mRNA and protein levels were determined in two large cohorts using quantitative real-time polymerase chain reaction (qRT-PCR) and tissue microarray (TMA) immunohistochemistry (IHC), respectively. We found that KRT8 expression was upregulated in ccRCC and vein tumor thrombi (VTTs). KRT8 overexpression in ccRCC was significantly correlated with aggressive characteristics and was predictive of a poor prognosis in ccRCC patients. Moreover, KRT8 overexpression in renal cancer cell lines promoted cell migration and invasion. In contrast, KRT8 knockdown suppressed ccRCC metastasis both in vitro and in vivo. In addition, our findings showed that KRT8 promoted ccRCC metastasis by increasing IL-11 expression, causing IL-11 autocrine induction, and triggering STAT3 signaling. Overall, this study established the significance of KRT8-IL-11 axis activation in aggressive ccRCC and defined a novel critical signaling mechanism that drives human ccRCC invasion and metastasis.

Photomodulation of the osteoclastogenic potential of oral squamous carcinoma cells

The treatment for oral cancer usually involves surgical excision followed by chemotherapy and/or radiotherapy. The combination of these therapies generally promotes a serious inflammation of the mucosa of the digestive tract, denominated mucositis, which compromises continuity of treatment. Photobiomodulation (PBM) therapy has been used successfully to reduce the oral mucositis, however there is still some controversy regarding the effects of this therapy on unintentionally irradiated tumor cells that may remain after cancer treatment. The aim of this study was to analyze the effect of PBM therapy (using parameters for mucositis) on the modulation of osteoclastogenic potential of a cell line derived from human lingual squamous cell carcinoma (SCC9). Previously irradiated SCC9 cells were co-cultured with human osteoclast precursors. Co-cultures performed with non-irradiated SCC9 cells served as control. After 7, 14 and 21 days the co-cultures were evaluated for the tartrate-resistant acid phosphatase (TRAP) activity, an osteoclastogenic marker. Additionally, the monocultures of SCC9 cells (non-irradiated and irradiated) were analyzed for cell viability/proliferation and for the expression of IL-11 and PTHrP. The irradiation of SCC9 cells with PBM with an energy density of 4 J/cm² decreased the pro-osteoclastogenic potential of those cells. This may represent a potential useful side effect of PBM therapy. PBM (using recommended parameters for mucositis treatment) decreases the osteoclastogenic potential of oral squamous carcinoma cells.

Functional characterization of the 12p12.1 renal cancer-susceptibility locus implicates BHLHE41

Genome-wide association studies have identified multiple renal cell carcinoma (RCC) susceptibility loci. Here, we use regional imputation and bioinformatics analysis of the 12p12.1 locus to identify the single-nucleotide polymorphism (SNP) rs7132434 as a potential functional variant. Luciferase assays demonstrate allele-specific regulatory activity and, together with data from electromobility shift assays, suggest allele-specific differences at rs7132434 for AP-1 transcription factor binding. In an analysis of The Cancer Genome Atlas data, SNPs highly correlated with rs7132434 show allele-specific differences in BHLHE41 expression (trend P value=6.3 × 10(-7)). Cells overexpressing BHLHE41 produce larger mouse xenograft tumours, while RNA-seq analysis reveals that constitutively increased BHLHE41 induces expression of IL-11. We conclude that the RCC risk allele at 12p12.1 maps to rs7132434, a functional variant in an enhancer that upregulates BHLHE41 expression which, in turn, induces IL-11, a member of the IL-6 cytokine family.

A panoramic review and in silico analysis of IL-11 structure and function

Human Interleukin (IL)-11 is a multifunctional cytokine, recognized for its thrombopoietic effects for more than two decades; clinically, IL-11 is used in the treatment of thrombocytopenia. IL-11 shares structural and functional similarities with IL-6, a related family member. In recent years, there has been a renewed interest in IL-11, because its distinct biological activities associated with cancers of epithelial origin and inflammatory disorders have been revealed. Although the crystal structure of IL-11 was resolved more than two years, a better understanding of the mechanisms of IL-11 action is required to further extend the clinical use of IL-11. This review will discuss the available structural, functional, and bioinformatics knowledge concerning IL-11 and will summarize its relationship with several diseases.

Downregulation of VEGFA inhibits proliferation, promotes apoptosis, and suppresses migration and invasion of renal clear cell carcinoma

Objective

The aim of this study was to investigate the effects of vascular endothelial growth factor A (VEGFA) on cell proliferation, apoptosis, migration, and invasion in renal clear cell carcinoma (RCCC).

Methods

Between June 2012 and June 2015, RCCC tissues were obtained for the experimental group, and RCCC adjacent tumor-free kidney parenchyma tissues were obtained for the control group. VEGFA mRNA and protein expressions and phosphoinositide 3-kinase, serine/threonine-specific protein kinase (AKT), and phosphorylated-AKT protein expressions were detected. The chemically synthesized specific siRNA using RNA interference technology was used to inhibit VEGFA gene expression in human RCCC 786-O cells. The negative control (NC) group was transfected with NC sequence, and the blank group was transfected with no sequence. Flow cytometry, scratch test, and cell-penetrating experiment were used to detect cell proliferation, apoptosis, migration, and invasion of 786-O cells.

Results

Positive expression of VEGFA protein was 60.62% in RCCC tissue and 18.34% in adjacent tissue with statistically significant difference (P<0.001). VEGFA protein and mRNA expressions were higher in RCCC tissue than those in adjacent tissue (both P<0.01). VEGF expression in RCCC tissue was associated with Fuhrman grading and American Joint Committee on Cancer staging (both P<0.05). After RCCC 786-O cells transfecting the VEGFA siRNA, the VEGFA mRNA and protein expressions and phosphoinositide 3-kinase and phosphorylated-AKT protein expressions were significantly decreased, cell proliferation was remarkably inhibited, cell apoptotic ratio was obviously increased, and migration distance and invasive cell number were markedly decreased compared to those in the NC group and the blank group (all P<0.05).

Conclusion

Inhibition of VEGFA inhibited proliferation, promoted apoptosis, and suppressed migration and invasion of RCCC 786-O cells. VEGF has a potential role in diagnosis and therapy of RCCC.

Emerging roles for IL-11 signaling in cancer development and progression: Focus on breast cancer

Interleukin (IL)-11 is a member of the IL-6 family of cytokines that is defined by the shared use of the GP130 signal transducing receptor subunit. In addition of its long recognized activities as a hemopoietic growth factor, IL-11 has an emerging role in epithelial cancer biology. Through the activation of the GP130-Janus kinase signaling cascade and associated transcription factor STAT3, IL-11 can confer many of the tumor intrinsic 'hallmark' capabilities to neoplastic cells, if they express the ligand-specific IL-11Rα receptor subunit. Accordingly, IL-11 signaling has recently been identified as a rate-limiting step for the growth tumors arising from the mucosa of the gastrointestinal tract. However, there is less appreciation for a potential role of IL-11 to support breast cancer progression, apart from its well documented capacity to facilitate bone metastasis. Here we review evidence that IL-11 expression in breast cancer correlates with poor disease outcome and discuss some of the molecular mechanisms that are likely to underpin these observations. These include the capacity of IL-11 to stimulate survival and proliferation of cancer cells alongside angiogenesis of the primary tumor and of metastatic progenies at distant organs. We review current strategies to interfere with IL-11 signaling and advocate that inhibition of IL-11 signaling may represent an emerging therapeutic opportunity for numerous cancers.