Interaction of cancer cell-derived Foxp3 and tumor microenvironment in human tongue squamous cell carcinoma

Complexity and diversity of FOXP3 isoforms: Novel insights into the regulation of the immune response in metastatic breast cancer

FOXP3 is a key transcription factor in the regulation of immune responses, and recent studies have uncovered the complexity and diversity of FOXP3 isoforms in various cancers, including metastatic breast cancers (mBCs). It has dual role in the tumor microenvironment of mBCs. This review aims to provide novel insights into the complexity and diversity of FOXP3 isoforms in the regulation of the immune response in breast cancer. We discuss the molecular mechanisms underlying the function of FOXP3 isoforms, including their interaction with other proteins, regulation of gene expression, and impact on the immune system. We also highlight the importance of understanding the role of FOXP3 isoforms in breast cancer and the potential for using them as therapeutic targets. This review highlights the crucial role of FOXP3 isoforms in the regulation of the immune response in breast cancer and underscores the need for further research to fully comprehend their complex and diverse functions.

LncRNA LINC00520 aggravates cell proliferation and migration in lung adenocarcinoma via a positive feedback loop

BACKGROUND

Lung adenocarcinoma (LUAD) is the most common histological subtype of primary lung cancer. To identify the biomarker of diagnosis for LUAD is of great significance. Long non-coding RNAs (lncRNAs) were previously revealed to exert vital effects in numerous cancers. LncRNA long intergenic non-protein coding RNA 520 (LINC00520) served as an oncogene in various cancers. Therefore, our study was specially designed to probe the role of LINC00520 in LUAD.

RESULTS

LINC00520 expression was detected by RT-qPCR. Next, function of LINC00520 in LUAD was verified by in vitro loss-of-function experiments. DNA pull down, ChIP, RIP, and luciferase reporter assays were conducted to reveal the regulatory mechanism of LINC00520. We found that LINC00520 was upregulated in LUAD. Additionally, LINC00520 upregulation is associated with the poor prognosis for patients with LUAD. Furthermore, LINC00520 downregulation suppressed LUAD cell proliferation and migration and induced cell apoptosis. Forkhead box P3 (FOXP3) is identified as the transcription factor to transcriptionally activate LINC00520. Moreover, LINC00520 positively upregulated FOXP3 expression via sponging miR-3611 in LUAD cells. Subsequently, rescue experiments delineated that miR-3611 downregulation or FOXP3 overexpression reversed the effects of silenced LINC00520 on proliferative and migratory capabilities in LUAD cells.

CONCLUSION

This study innovatively indicated that lncRNA LINC00520 facilitated cell proliferative and migratory abilities in LUAD through interacting with miR-3611 and targeting FOXP3, which may provide a potential novel insight for treatment of LUAD.

MiR-106b-5p regulates the migration and invasion of colorectal cancer cells by targeting FAT4

MicroRNA-106b-5p (miR-106b-5p) is involved in the development of many cancers including colorectal cancer (CRC), and FAT4 is correlated with regulation of growth and apoptosis of cancer cells. The present study aimed to investigate the relation between FAT4 and miR-106b-5p and the underlying mechanism of the two on the development of CRC. Quantitative real-time PCR (qRT-PCR) assay and Western blot (WB) analysis were performed to detect the expressions of messenger RNAs (mRNAs), microRNAs (miRNAs) and proteins. The viability of CRC cells was detected by cell counting kit-8 (CCK-8). Scratch test and transwell assay were performed to measure the migration and invasion of CRC cell. Tumor angiogenesis was simulated by in vitro angiogenesis experiment. Dual-luciferase reporter assay was performed to verify the targeting relation between miR-106b-5p and FAT4. The study found that the expression of FAT4 was down-regulated and that of miR-106b-5p was up-regulated in CRC tissues. Overexpression of FAT4 resulted in decreased proliferation, migration, invasion and angiogenesis of CRC cells, whereas silencing of FAT4 led to the opposite results. In rescue experiment, miR-106b-5p partially reversed the function of FAT4 in CRC cells, thus playing a carcinogenic role by targeting FAT4 in the CRC cells.

PDGF-BB exhibited therapeutic effects on rat model of bisphosphonate-related osteonecrosis of the jaw by enhancing angiogenesis and osteogenesis

The mechanism and effective treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ) are still uncertain. Our previous study revealed that zoledronate (ZOL) preferentially inhibited osteoclasts formation and platelet-derived growth factor-BB (PDGF-BB) secretion, causing suppression of angiogenesis and osteogenesis in vitro. The present study aimed to elucidate whether PDGF-BB had therapeutic effects on rat model of BRONJ by enhancing angiogenesis and angiogenesis. Firstly, rat model of BRONJ was established by ZOL and dexamethasone administration, followed by teeth extraction. The occurrence of BRONJ was confirmed and detected dead bone formation by maxillae examination, micro-CT scan and HE staining (10/10). Compared to control rats (0/10), both angiogenesis and mature bone formation were suppressed in BRONJ-like rats, evidenced by enzyme-linked immunosorbent assay (ELISA) for VEGF (P < 0.01), immunohistochemistry of CD31 (P < 0.05) and OCN (P < 0.01). Moreover, in the early stage of bone healing, the number of preosteoclasts (P < 0.001) and PDGF-BB secretion (P < 0.05) were significantly decreased in bisphosphonates-treated rats, along with the declined numbers of microvessels (P < 0.05) and osteoblasts (P < 0.05). In vitro study, CCK8 assay, alizarin red S staining and western blot assay showed that mandible-derived bone marrow mesenchymal stem cells (BMMSCs) in BRONJ-like rats presented suppressed functions of proliferation, osteogenesis and angiogenesis. Interestingly, recombinant PDGF-BB was able to rescue the impaired functions of BMMSCs derived from BRONJ-like rats at more than 10 ng/ml. Then fibrin sealant with or without recombinant PDGF-BB were tamped into the socket after debridement in BRONJ rats. After 8 weeks, fibrin sealant containing PDGF-BB showed significant therapeutic effects on BRONJ-like rats (bone healing: 8/10 vs 3/10, P < 0.05) with enhancing microvessels and mature bone formation. Our study suggested that the inhibition of angiogenesis and osteogenesis, the potential mechanisms of BRONJ, might partly result from suppression of PDGF-BB secretion in the early stage of bone healing. PDGF-BB local treatment after debridement might avail the healing of BRONJ by increasing angiogenesis and osteogenesis.

Development of an Immunogenomic Landscape-Based Prognostic Index of Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the eighth leading cancer by incidence worldwide, with approximately 700,000 new cases in 2018 (accounting for 11% of all cancers). The occurrence and development of tumors are closely related to the immunological function of the body and sensitivity to treatment schemes as well as prognosis. It is urgent for clinicians to systematically study patients’ immune gene maps to help select a treatment plan and analyze the potential to cure HNSCC. Here, the transcriptomic data of HNSCC samples were downloaded from The Cancer Genome Atlas (TCGA), and 4,793 genes differentially expressed in normal and cancer tissues of HNSCC were identified, including 1,182 downregulated and 3,611 upregulated genes. From these genes, 400 differentially expressed immune-related genes (IRGs) were extracted, including 95 downregulated genes and 305 upregulated genes. The prognostic values of IRGs were evaluated by univariate Cox analysis, and 236 genes that were significantly related to the overall survival (OS) of patients were identified. The signaling pathways that play roles in the prognosis of IRGs were investigated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, and the expression profiles of IRGs and OS in 499 HNSCC patients based on TCGA dataset were integrated. Potential molecular mechanisms and characteristics of these HNSCC-specific IRGs were further explored with the help of a new prognostic index based on IRGs developed by least absolute shrinkage and selection operator (LASSO) Cox analysis. A total of 64 hub genes (IRGs associated with prognosis) were markedly associated with the clinical outcome of HNSCC patients. KEGG functional enrichment analysis revealed that these genes were actively involved in several pathways, e.g., cytokine–cytokine receptor interaction, T-cell receptor signaling, and natural killer cell-mediated cytotoxicity. IRG-based prognostic signatures performed moderately in prognostic predictions. Interestingly, the prognostic index based on IRGs reflected infiltration by several types of immune cells. These data screened several IRGs of clinical significance and revealed drivers of the immune repertoire, demonstrating the importance of a personalized IRG-based immune signature in the recognition, surveillance, and prognosis of HNSCC.

Positive Role of Chinese Herbal Medicine in Cancer Immune Regulation

Complementary and alternative medicine (CAM) plays a critical role in treating cancer patients. Traditional Chinese Medicine (TCM) is the main component of CAM. TCM, especially Chinese Herbal Medicine (CHM), has been increasingly used in China, some other Asian countries and European countries. It has been proven to enhance the efficacy of chemotherapy, radiotherapy, targeted-therapy, and immunotherapy. It lessens the damage caused by these therapies. CHM functions on cancer by inhibiting tumor progression and improving an organism’s immune system. Increasing evidence has shown that many CHM exert favorable effects on the immune regulation. We will summarize the role of CHM on patient’s immune system when treating cancer patients. Our evidence reveals that single herbs, including their extracts, compound formulations, and preparations, will provide current advances on CHM study, especially from the perspective of immune regulation and novel insights for CHM application in clinic. The main herbs used to treat cancer patients are health-strengthening (Fu-Zheng) herbs and pathogen eliminating (Qu-Xie) herbs. The key mechanism is regulating the immune system of cancer patients. Firstly, health-strengthening herbs are mainly functioned as immune regulatory effectors on cancer. Secondly, some of the compound formulations mainly strengthen the health of patients by regulating the immune system of cancer patients. Lastly, some Chinese medicine preparations are widely used to treat cancer for their properties of spiriting vital energy and anti-cancer effects, mainly by improving immunity. CHM plays a positive role in regulating patients’ immune system, which helps cancer patients to fight against cancer itself and finally improves patients’ life quality.

Pyruvate Kinase M2: a Metabolic Bug in Re-Wiring the Tumor Microenvironment

Metabolic reprogramming is a newly emerged hallmark of cancer attaining a recent consideration as an essential factor for the progression and endurance of cancer cells. A prime event of this altered metabolism is increased glucose uptake and discharge of lactate into the cells surrounding constructing a favorable tumor niche. Several oncogenic factors help in promoting this consequence including, pyruvate kinase M2 (PKM2) a rate-limiting enzyme of glycolysis in tumor metabolism via exhibiting its low pyruvate kinase activity and nuclear moon-lightening functions to increase the synthesis of lactate and macromolecules for tumor proliferation. Not only its role in cancer cells but also its role in the tumor microenvironment cells has to be understood for developing the small molecules against it which is lacking with the literature till date. Therefore, in this present review, the role of PKM2 with respect to various tumor niche cells will be clarified. Further, it highlights the updated list of therapeutics targeting PKM2 pre-clinically and clinically with their added limitations. This upgraded understanding of PKM2 may provide a pace for the reader in developing chemotherapeutic strategies for better clinical survival with limited resistance.

TGFβ induces stemness through non-canonical AKT-FOXO3a axis in oral squamous cell carcinoma

Background

FOXO3a has been widely regarded as a tumor suppressor. It also plays a paradoxical role in regulating the cancer stem cells (CSCs), responsible for tumor-initiation, chemo-resistance, and recurrence in various solid tumors, including oral squamous cell carcinoma (OSCC). This study aims to uncover the role of FOXO3a and its importance for a non-canonical pathway of TGFβ in regulating the OSCC stemness.

Methods

We identified FOXO3a expression in OSCC tissues and cell lines using immunohistochemistry and western blot. The correlation between FOXO3a and stemness was evaluated. Stable cell lines with differential expression of FOXO3a were constructed using lentiviruses. The effects of FOXO3a on stem-cell like properties in OSCC was further evaluated in vitro and in vivo. We also explored the effect of TGFβ on FOXO3a with respect to its expression and function.

Findings

Our findings suggest that FOXO3a was widely expressed and negatively correlated with the stemness in OSCC. This regulation can be abolished by TGFβ through phosphorylation, nuclear exclusion, and degradation in the non-Smad pathway. We also observed that non-Smad AKT-FOXO3a axis is essential to regulate stemness of CSCs by TGFβ.

Interpretation

TGFβ induces stemness through non-canonical AKT-FOXO3a axis in OSCC. Our study provides a foundation to understand the mechanism of CSCs and a possible therapeutic target to eliminate CSCs.

Analysis of Treg/Th17 cells in patients with tongue squamous cell carcinoma

The aim of the present study was to analyze the percentage of regulatory T cells (Treg) and T helper cell 17 (Th17) cells in the peripheral blood of patients with tongue squamous cell carcinoma (TSCC) to provide novel insight into the development of immune-targeting therapies for TSCC. Peripheral blood samples were collected from 40 patients with TSCC then the peripheral blood mononuclear cells (PBMCs) and plasma were isolated for flow cytometry, cytometric bead array and reverse transcription-quantitative PCR. Results demonstrated that the percentage of cluster of differentiation (CD)4+ T cells in the peripheral blood of patients with TSCC decreased significantly compared with the control. However, the percentage of Treg and Th17 cells increased significantly compared with the control. The levels of interleukin (IL)-10 and IL-17a increased significantly in patients with TSCC. Expression of IL-10 and IL-17 in the advanced stages of cancer (stage III or IV) were significantly higher compared with the early stages (I and II). The mRNA expression levels of the transcription factors forkhead box protein 3 and RAR-related orphan receptor-γ increased significantly with stage of cancer. The percentage of Treg cells and Th17 cells increased significantly in patients with TSCC suggesting that there was an imbalance between Treg and Th17 cells. In conclusion, altered Treg/Th17 balance in TSCC may promote the disease progression and these results provide a theoretical basis for the development of immunomodulators targeting Treg/Th17.