MicroRNA regulation of TRAIL mediated signaling in different cancers: Control of micro steering wheels during the journey from bench-top to the bedside

A Comprehensive Insight into Apoptosis: Molecular Mechanisms, Signaling Pathways, and Modulating Therapeutics

Apoptosis, or programmed cell death, is a fundamental biological process essential for maintaining tissue homeostasis. Dysregulation of apoptosis is implicated in a variety of diseases, including cancer, neurodegenerative disorders, and autoimmune conditions. This review provides an in-depth insight into the molecular mechanisms and signaling pathways that regulate apoptosis, highlighting both intrinsic and extrinsic pathways. Additionally, the review explains the tumor microenvironment's influence on apoptosis and its implications for cancer therapy resistance. Understanding the complex interplay between apoptotic signaling and cellular responses is crucial for developing targeted therapies that can effectively manage diseases associated with apoptosis dysregulation. The effects of conventional therapeutics and alternative substances with natural sources such as herbal compounds, alongside vitamins, minerals, and trace elements on cellular homeostasis and disease pathogenesis have been thoroughly investigated. Moreover, recent advances in therapeutic strategies aimed at modulating apoptosis are discussed, with a focus on novel interventions such as nutrition bio shield dietary supplement. These emerging approaches offer potential benefits beyond conventional treatments by selectively targeting apoptotic pathways to inhibit cancer progression and metastasis. By integrating insights from recent studies, this review aims to enhance our understanding of apoptosis and guide future research in developing innovative therapeutic approaches.

Cytoplasmic TP53INP2 acts as an apoptosis partner in TRAIL treatment: the synergistic effect of TRAIL with venetoclax in TP53INP2-positive acute myeloid leukemia

BACKGROUND

Acute myeloid leukemia (AML) is a hematopoietic malignancy with poor outcomes, especially in older AML patients. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer drug because it selectively induces the extrinsic apoptosis of tumor cells without affecting normal cells. However, clinical trials have shown that the responses of patients to TRAIL are significantly heterogeneous. It is necessary to explore predictable biomarkers for the preselection of AML patients with better responsiveness to TRAIL. Here, we investigated the critical role of tumor protein p53 inducible nuclear protein 2 (TP53INP2) in the AML cell response to TRAIL treatment.

METHODS

First, the relationship between TP53INP2 and the sensitivity of AML cells to TRAIL was determined by bioinformatics analysis of Cancer Cell Line Encyclopedia datasets, Cell Counting Kit-8 assays, flow cytometry (FCM) and cell line-derived xenograft (CDX) mouse models. Second, the mechanisms by which TP53INP2 participates in the response to TRAIL were analyzed by Western blot, ubiquitination, coimmunoprecipitation and immunofluorescence assays. Finally, the effect of TRAIL alone or in combination with the BCL-2 inhibitor venetoclax (VEN) on cell survival was explored using colony formation and FCM assays, and the effect on leukemogenesis was further investigated in a patient-derived xenograft (PDX) mouse model.

RESULTS

AML cells with high TP53INP2 expression were more sensitive to TRAIL in vitro and in vivo. Gain- and loss-of-function studies demonstrated that TP53INP2 significantly enhanced TRAIL-induced apoptosis, especially in AML cells with nucleophosmin 1 (NPM1) mutations. Mechanistically, cytoplasmic TP53INP2 maintained by mutant NPM1 functions as a scaffold bridging the ubiquitin ligase TRAF6 to caspase-8 (CASP 8), thereby promoting the ubiquitination and activation of the CASP 8 pathway. More importantly, simultaneously stimulating extrinsic and intrinsic apoptosis signaling pathways with TRAIL and VEN showed strong synergistic antileukemic activity in AML cells with high levels of TP53INP2.

CONCLUSION

Our findings revealed that TP53INP2 is a predictor of responsiveness to TRAIL treatment and supported a potentially individualized therapeutic strategy for TP53INP2-positive AML patients.

Epigenetic regulation of immunosuppressive tumor-associated macrophages through dysregulated microRNAs

Macrophages are immune cells that play different roles under different physiological conditions. They are present in all tissues where they primarily protect from bacteria and pathogens in addition to assisting in tissue repair. During tumor progression, macrophages can exert contrasting effects based on the M1 vs. M2 polarization. The M2 macrophages support tumor growth through mechanisms that help suppress immune responses and/or circumvent immune-surveillance. A number of such mechanisms such as production of IL-10 and arginase, and expression of PD-L1, V-domain Ig suppressor of T cell activation and B7 family molecule B7-H4 are now believed central to the immunosuppressive effects of tumor-associated macrophages (TAMs). Emerging data has identified epigenetic regulation of these immunosuppressive mechanisms by small non-coding RNAs, the microRNAs (miRNAs). This review discusses the available literature on the subject, including the exosomes mediated transfer of miRNAs between cancer cells and the macrophages within the tumor microenvironment. A number of miRNAs are now believed to be involved in TAMs' production of IL-10 and expression of PD-L1 while the information on such regulation of other immunosuppressive mechanisms is slowly emerging. A better understanding of epigenetic regulation of macrophages-mediated immunosuppressive effect can help identify novel targets for therapy and aid the design of future studies aimed at sensitizing tumors to immune responses.

Realizing the Potential of Blueberry as Natural Inhibitor of Metastasis and Powerful Apoptosis Inducer: Tapping the Treasure Trove for Effective Regulation of Cell Signaling Pathways

Blueberries belong to the genus Vaccinium of the family Ericaceae. Rapidly accumulating experimentally verified data is uncovering the tremendous pharmacological properties of biologically active constituents of blueberries against different diseases. Our rapidly evolving knowledge about the multifaceted nature of cancer has opened new horizons to search for different strategies to target multiple effectors of oncogenic networks to effectively inhibit cancer onset and progression. Excitingly, whole blueberry powder and various bioactive constituents (pterostilbene, malvidin-3-galactoside) of blueberries have been shown to efficiently inhibit metastasis in animal models. These results are encouraging and future studies must focus on the identification of cell signaling pathways effectively modulated by blueberries in different cancers. It seems exciting to note that researchers are focusing on metastasis inhibitory effects of blueberry; however, to reap full benefits, it is necessary to take a step back and critically re-interpret the mechanisms used by active components of blueberry to inhibit or prevent metastasis. JAK/STAT, TGF/SMAD, Notch, SHH/GLI, and Wnt/ β-Catenin have been shown to be directly involved in the regulation of metastasis. However, because of limited studies, it is difficult to critically assess the true potential of blueberry. Loss of apoptosis, metastasis and deregulation of signaling pathways are branching trajectories of molecular oncology. Accordingly, we have to emphasize on these essential facets to realistically claim blueberry as "Superfood". Different clinical trials have been conducted to gather clinical evidence about the chemopreventive role of blueberry or its bioactive components in cancer patients. But it seems clear that because of the lack of sufficient proof-of-concept studies, we cannot extract significant information about the transition of blueberry into the next phases of clinical trials. Overview of the existing scientific evidence revealed visible knowledge gaps and a better understanding of the targets of blueberry will be helpful in efficient and meaningful translation of laboratory findings to clinically effective therapeutics.

Toward Regulatory Effects of Curcumin on Transforming Growth Factor-Beta Across Different Diseases: A Review

Immune response, proliferation, migration and angiogenesis are juts a few of cellular events that are regulated by transforming growth factor-β (TGF-β) in cells. A number of studies have documented that TGF-β undergoes abnormal expression in different diseases, e.g., diabetes, cancer, fibrosis, asthma, arthritis, among others. This has led to great fascination into this signaling pathway and developing agents with modulatory impact on TGF-β. Curcumin, a natural-based compound, is obtained from rhizome and roots of turmeric plant. It has a number of pharmacological activities including antioxidant, anti-inflammatory, anti-tumor, anti-diabetes and so on. Noteworthy, it has been demonstrated that curcumin affects different molecular signaling pathways such as Wnt/β-catenin, Nrf2, AMPK, mitogen-activated protein kinase and so on. In the present review, we evaluate the potential of curcumin in regulation of TGF-β signaling pathway to corelate it with therapeutic impacts of curcumin. By modulation of TGF-β (both upregulation and down-regulation), curcumin ameliorates fibrosis, neurological disorders, liver disease, diabetes and asthma. Besides, curcumin targets TGF-β signaling pathway which is capable of suppressing proliferation of tumor cells and invading cancer cells.

Progress in Delivery of siRNA-Based Therapeutics Employing Nano-Vehicles for Treatment of Prostate Cancer

Prostate cancer (PCa) accounts for a high number of deaths in males with no available curative treatments. Patients with PCa are commonly diagnosed in advanced stages due to the lack of symptoms in the early stages. Recently, the research focus was directed toward gene editing in cancer therapy. Small interfering RNA (siRNA) intervention is considered as a powerful tool for gene silencing (knockdown), enabling the suppression of oncogene factors in cancer. This strategy is applied to the treatment of various cancers including PCa. The siRNA can inhibit proliferation and invasion of PCa cells and is able to promote the anti-tumor activity of chemotherapeutic agents. However, the off-target effects of siRNA therapy remarkably reduce its efficacy in PCa therapy. To date, various carriers were designed to improve the delivery of siRNA and, among them, nanoparticles are of importance. Nanoparticles enable the targeted delivery of siRNAs and enhance their potential in the downregulation of target genes of interest. Additionally, nanoparticles can provide a platform for the co-delivery of siRNAs and anti-tumor drugs, resulting in decreased growth and migration of PCa cells. The efficacy, specificity, and delivery of siRNAs are comprehensively discussed in this review to direct further studies toward using siRNAs and their nanoscale-delivery systems in PCa therapy and perhaps other cancer types.

PD-L1 Under Regulation of miR-429 Influences the Sensitivity of Gastric Cancer Cells to TRAIL by Binding of EGFR

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has received extensive attention as a cancer therapeutic due to its high propensity for tumor targeting with minimal toxicity to healthy tissue. Gastric cancer (GCa) cells show high levels of TRAIL resistance. Epidermal growth factor receptor (EGFR) antagonizes TRAIL-induced apoptosis, but the mechanisms of these effects remain unclear. Our past research confirmed TRAIL-resistant (BGC823 and SGC7901) and TRAIL-sensitive cells (HGC27 and MKN45). miR-429 associated with TRAIL sensitivity was screened using microRNA arrays. The transfection of mimics and inhibitors confirmed that miR-429 negatively correlated with GCa TRAIL resistance. The target gene of miR-429 was identified as PD-L1, which positively correlated with TRAIL resistance through gene silencing and recovery experiments. Using co-immunoprecipitation (co-IP) and proximity ligation assay, we demonstrated that the pro-survival effects of PD-L1 are mediated through the binding and activation of EGFR. Cell viability experiments demonstrated that PD-L1 is key to the maintenance of cell viability in TRAIL-treated cells. This indicated that PD-L1 binds to and participates in EGFR activation through miR-429 regulation to antagonize TRAIL-induced apoptosis. This provides a new theoretical basis for the combination of the EGFR monoclonal antibodies including cetuximab, PD-L1 inhibitors, and human recombinant TRAIL in gastric cancer therapy and can filter patients who are currently sensitive to TRAIL treatment.

PTEN: What we know of the function and regulation of this onco-suppressor factor in bladder cancer?

Bladder cancer accounts for high morbidity and mortality around the world and its incidence rate is suggested to be higher in following years. A number of factors involve in bladder cancer development such as lifestyle and drugs. However, it appears that genetic factors play a significant role in bladder cancer development and progression. Phosphatase and tensin homolog (PTEN) is a cancer-related transcription factor that is corelated with reduced proliferation and invasion of cancer cells by negatively targeting PI3K/Akt/mTOR signaling pathway. In the present review, we aimed to explore the role of PTEN in bladder cancer cells and how upstream modulators affect PTEN in this life-threatening disorder. Down-regulation of PTEN is associated with poor prognosis, chemoresistance and progression of cancer cells. Besides, microRNAs, long non-coding RNAs, circular RNAs and other molecular pathways such as NF-kB are able to target PTEN in bladder cancer cells. Notably, anti-tumor drugs such as kaempferol, β-elemene and sorafenib upregulate the expression of PTEN to exert their inhibitory effects on bladder cancer cells.

miR-150-5p represses TP53 tumor suppressor gene to promote proliferation of colon adenocarcinoma

MicroRNAs (miRNAs) play a critical role in regulation of numerous biological processes and pathogenesis of a variety of diseases. In addition, miRNAs contribute to carcinogenesis by acting as oncogenic or tumor suppressive. Circulating miRNAs including miR-150-5p are associated with colorectal cancer progression, and the putative targets of miR-150-5p include tumor suppressor gene, TP53. Here we sought to investigate the role of miR-150-5p-TP53 signaling pathway in proliferation of colon cancer and to determine expression levels of miR-miR-150-5p and TP53 in colon adenocarcinoma and adjacent non-cancerous tissue samples, or in human colon adenocarcinoma cell lines. MTT assay was used to determine proliferation and apoptosis in cell lines. Furthermore, we used Western blot to determine levels of cell cycle regulators with anti-miR-150-5p or apoptosis with overexpression of TP53. Our results show that expression levels of miR-150-5p were significantly elevated in clinical specimens from cancer patients. We further showed that inhibition of miR-150-5p increased TP53, and in turn, suppression of proliferation of colon adenocarcinoma. Moreover, inhibition of miR-150-5p or overexpression of TP53 caused cell arrest or apoptosis in colon adenocarcinoma. Our results support that miR-150-5p-TP53 pathway plays an important role in regulation of proliferation, cell arrest, and apoptosis in colon cancer, and could be an attractive target for therapy.