Nonsteroidal Anti-Inflammatory Drugs as PPARγ Agonists Can Induce PRODH/POX-Dependent Apoptosis in Breast Cancer Cells: New Alternative Pathway in NSAID-Induced Apoptosis

Exploring COX-Independent Pathways: A Novel Approach for Meloxicam and Other NSAIDs in Cancer and Cardiovascular Disease Treatment

As a fundamental process of innate immunity, inflammation is associated with the pathologic process of various diseases and constitutes a prevalent risk factor for both cancer and cardiovascular disease (CVD). Studies have indicated that several non-steroidal anti-inflammatory drugs (NSAIDs), including Meloxicam, may prevent tumorigenesis, reduce the risk of carcinogenesis, improve the efficacy of anticancer therapies, and reduce the risk of CVD, in addition to controlling the body's inflammatory imbalances. Traditionally, most NSAIDs work by inhibiting cyclooxygenase (COX) activity, thereby blocking the synthesis of prostaglandins (PGs), which play a role in inflammation, cancer, and various cardiovascular conditions. However, long-term COX inhibition and reduced PGs synthesis can result in serious side effects. Recent studies have increasingly shown that some selective COX-2 inhibitors and NSAIDs, such as Meloxicam, may exert effects beyond COX inhibition. This emerging understanding prompts a re-evaluation of the mechanisms by which NSAIDs operate, suggesting that their benefits in cancer and CVD treatment may not solely depend on COX targeting. In this review, we will explore the potential COX-independent mechanisms of Meloxicam and other NSAIDs in addressing oncology and cardiovascular health.

PRODH Regulates Tamoxifen Resistance through Ferroptosis in Breast Cancer Cells

BACKGROUND

Estrogen receptor-positive breast cancer accounts for around 70% of all cases. Tamoxifen, an anti-estrogenic inhibitor, is the primary drug used for this type of breast cancer treatment. However, tamoxifen resistance is a major challenge in clinics. Metabolic reprogramming, an emerging hallmark of cancer, plays a key role in cancer initiation, progression, and therapy resistance. The metabolism of non-essential amino acids such as serine, proline, and glutamine is involved in tumor metabolism reprogramming. Although the association of glutamine metabolism with tamoxifen resistance has been well established, the role of proline metabolism and its critical enzyme PRODH is unknown.

OBJECTIVE

The aim of this study is to explore the role and mechanism of PRODH in tamoxifen resistance in breast cancer cells.

METHODS

PRODH and GPX4 expressions in tamoxifen-resistant cells were detected using real-time PCR and Western blot analysis. The breast cells' response to tamoxifen was measured using MTT assays. Trans-well assays were used to detect cell migration and invasion. A Xenograft tumor assay was used to detect the role of PRODH in tumor growth. Reactive oxygen species were measured using flow cytometry.

RESULTS

PRODH expression is reduced in tamoxifen-resistant cells, and its overexpression enhances tamoxifen response in vitro and in vivo. Conversely, PRODH knockdown confers tamoxifen resistance in tamoxifen-sensitive cells. Mechanistic studies show that ferroptosis is inhibited in tamoxifen-resistant cells and overexpression of PRODH restores the ferroptosis in tamoxifen-resistant cells. Moreover, Ferrostatin-1 (Fer-1), the ferroptosis inhibitor, reversed the effect of PRODH on tamoxifen resistance.

CONCLUSIONS

These findings suggest that PRODH regulates tamoxifen resistance by regulating ferroptosis in tamoxifen-resistant cells.

Elsayed A, López-Berestein G, Amero P, Rodríguez-Aguayo C. An Overview of the Immune Modulatory Properties of Long Non-Coding RNAs and Their Potential Use as Therapeutic Targets in Cancer

Long non-coding RNAs (lncRNAs) play pivotal roles in regulating immune responses, immune cell differentiation, activation, and inflammatory processes. In cancer, they are gaining prominence as potential therapeutic targets due to their ability to regulate immune checkpoint molecules and immune-related factors, suggesting avenues for bolstering anti-tumor immune responses. Here, we explore the mechanistic insights into lncRNA-mediated immune modulation, highlighting their impact on immunity. Additionally, we discuss their potential to enhance cancer immunotherapy, augmenting the effectiveness of immune checkpoint inhibitors and adoptive T cell therapies. LncRNAs as therapeutic targets hold the promise of revolutionizing cancer treatments, inspiring further research in this field with substantial clinical implications.

Can proline dehydrogenase-a key enzyme involved in proline metabolism-be a novel target for cancer therapy?

Emerging evidence suggests that proline metabolism is important for regulating the survival and death of different types of cancer cells. Proline dehydrogenase (PRODH), an enzyme catalyzing proline catabolism, and the degradation products of proline by PRODH, such as ATP and ROS, are known to play critical roles in cancer progression. Notably, the role of PRODH in cancer is still complicated and unclear, and primarily depends on the cancer type and tumor microenvironment. For instance, PRODH induces apoptosis and senescence through ROS signaling in different types of cancers, while as a protumor factor, PRODH promotes malignant phenotypes of certain tumors under stresses such as hypoxia. In order to assess whether PRODH can serve as a novel target for cancer therapy, we will provide an overview of the biological functions of PRODH and its double-edged role in cancer in this article.

Nuclear Receptors in Health and Diseases

Nuclear receptors (NRs) are a vital superfamily of transcription factors that play crucial roles in physiology and pharmacology [...].

Cyperotundone combined with adriamycin induces apoptosis in MCF-7 and MCF-7/ADR cancer cells by ROS generation and NRF2/ARE signaling pathway

Breast cancer has become the most prevalent cancer, globally. Adriamycin is a first-line chemotherapeutic agent, however, cancer cells acquire resistance to it, which is one of the most common causes of treatment failure. ROS and NRF2 are essential oxidative stress factors that play a key role in the oxidative stress process and are associated with cancer. Our goal is to create novel therapeutic drugs or chemical sensitizers that will improve chemotherapy sensitivity. The optimal concentration and duration for MCF-7 and MCF-7/ADR cells in ADR and CYT were determined using the CCK-8 assay. We found that ADR + CYT inhibited the activity of MCF-7 and MCF-7/ADR cells in breast cancer, as well as causing apoptosis in MCF-7 and MCF-7/ADR cells and blocking the cell cycle in the G0/G1 phase. ADR + CYT induces apoptosis in MCF-7 and MCF-7/ADR cells through ROS generation and the P62/NRF2/HO-1 signaling pathway. In breast cancer-bearing nude mice, ADR + CYT effectively suppressed tumor development in vivo. Overall, our findings showed that CYT in combination with ADR has potent anti-breast cancer cell activity both in vivo and in vitro, suggesting CYT as the main drug used to improve chemosensitivity.

Ketoprofen suppresses triple negative breast cancer cell growth by inducing apoptosis and inhibiting autophagy

BACKGROUND

Triple-negative breast cancer (TNBC) is an invasive phenotype with undesirable clinical features, poor prognosis, and therapy resistance. Ketoprofen is a Non-steroidal anti-inflammatory drug (NSAID) with anti-tumor properties.

AIM

To investigate the effects of Ketoprofen on apoptosis and autophagy in TNBC cell line MDA-MB-231.

METHODS

The cytotoxic activity of Ketoprofen was assayed by the MTS method. Flowcytometry was utilized to measure the number of apoptotic MDA-MB-231 cells. The expression levels of apoptosis and autophagy markers, JAK2 and STAT3 were determined using quantitative real time-PCR (qRT-PCR) and western blotting methods.

RESULTS

Ketoprofen significantly decreased the proliferation of MDA-MB-231 cells compared to control cells. It also considerably induced apoptosis and apoptotic markers in these cells in comparison to controls. Treating the MADA-MB-231 cell line with Ketoprofen had an inhibitory effect on autophagy markers in this cell line. The use of FasL, as a death ligand, and ZB4, as an antibody that blocks the extrinsic pathway of apoptosis, revealed the involvement of the extrinsic pathway in the apoptosis-stimulating effect of Ketoprofen in the MADA-MB-231 cell line. Ketoprofen also hindered the phosphorylation and activation of JAK2 and STAT molecules leading to the inhibition of the JAK/STAT pathway in this TNBC cell line.

CONCLUSION

The outcomes of this study uncovered the anti-TNBC activity of Ketoprofen by inducing apoptosis and inhibiting viability and autophagy in MADA-MB-231 cells. Our data also suggested that Ketoprofen impedes apoptosis in TNBC cells by two different mechanisms including the induction of the extrinsic apoptotic pathway and inhibition of the JAK/STAT signaling.

Interaction of Oxicam Derivatives with the Artificial Models of Biological Membranes-Calorimetric and Fluorescence Spectroscopic Study

The modified 1,2-benzothiazine analogues designed as new drug candidates and discussed in this paper are oxicam derivatives. Oxicams are a class of non-steroidal anti-inflammatory drugs (NSAIDs). Their biological target is cyclooxygenase (COX), a membrane protein associated with the phospholipid bilayer. In recent decades, it has been proven that the biological effect of NSAIDs may be closely related to their interaction at the level of the biological membrane. These processes are often complicated and the biological membranes themselves are very complex. Therefore, to study these mechanisms, simplified models of biological membranes are used. To characterize the interaction of six oxicam derivatives with DPPC, DMPC and EYPC, artificial models of biological membranes (multi-bilayers or liposomes), differential scanning calorimetry (DSC) and fluorescence spectroscopy techniques were applied. In spectroscopic measurements, two fluorescent probes (Laurdan and Prodan) localized in different membrane segments were used. All tested oxicam derivatives interacted with the lipid bilayers and may penetrate the artificial models of biological membranes. They intercalated into the lipid bilayers and were located in the vicinity of the polar/apolar membrane interface. Moreover, a good drug candidate should not only have high efficiency against a molecular target but also exhibit strictly defined ADMET parameters, therefore these activities of the studied compounds were also estimated.

Peroxisome Proliferator-Activated Receptors and the Hallmarks of Cancer

Peroxisome proliferator-activated receptors (PPARs) function as nuclear transcription factors upon the binding of physiological or pharmacological ligands and heterodimerization with retinoic X receptors. Physiological ligands include fatty acids and fatty-acid-derived compounds with low specificity for the different PPAR subtypes (alpha, beta/delta, and gamma). For each of the PPAR subtypes, specific pharmacological agonists and antagonists, as well as pan-agonists, are available. In agreement with their natural ligands, PPARs are mainly focused on as targets for the treatment of metabolic syndrome and its associated complications. Nevertheless, many publications are available that implicate PPARs in malignancies. In several instances, they are controversial for very similar models. Thus, to better predict the potential use of PPAR modulators for personalized medicine in therapies against malignancies, it seems necessary and timely to review the three PPARs in relation to the didactic concept of cancer hallmark capabilities. We previously described the functions of PPAR beta/delta with respect to the cancer hallmarks and reviewed the implications of all PPARs in angiogenesis. Thus, the current review updates our knowledge on PPAR beta and the hallmarks of cancer and extends the concept to PPAR alpha and PPAR gamma.

Metformin Induces PRODH/POX-Dependent Apoptosis in Breast Cancer Cells

Although the antineoplastic activity of metformin (MET) is well established, the underlying mechanism of the activity is not understood. Since MET activates AMP kinase (AMPK) and proline dehydrogenase/proline oxidase (PRODH/POX) is stimulated by AMPK ligands (implicated in the regulation of cancer cell survival/apoptosis), the effect of MET on PRODH/POX-dependent apoptosis in wild-type MCF-7 cells (MCF-7^WT) and POX knockdown MCF-7 cells (MCF-7^crPOX cells) was studied. PRODH/POX catalyzes proline degradation generating ROS-induced apoptosis or autophagy. Availability of proline for PRODH/POX functions is regulated by the activity of prolidase (enzyme releasing proline from imidodipeptides), collagen biosynthesis (process consuming proline), and metabolism of proline, ornithine, and glutamic acid. We have found that MET is cytotoxic for MCF-7 cells (IC50∼17 mM), and to the lower extent for MCF-7^crPOX cells (IC50∼28 mM). In MCF-7^WT cells, the effect was accompanied by the inhibition of DNA biosynthesis, collagen biosynthesis, stimulation of ROS formation, AMPKα phosphorylation, and expression of prolidase, p53, caspase 8, caspase 9, and cleaved PARP. In MET-treated MCF-7^crPOX cells, the processes were less affected than in MCF-7^WT cells and the expression of caspase 9 was decreased, while cleaved caspase 8 and cleaved PARP were not detected. The effects were accompanied by an increase in the prolidase activity and proline concentration. The mechanism for MET-induced apoptosis involves the up-regulation of prolidase activity and a decrease in collagen biosynthesis contributing to an increase in the concentration of substrate (proline) for PRODH/POX-dependent ROS formation and activation of caspases −9 and −8. The data suggest that PRODH/POX participates in the MET-induced intrinsic and extrinsic apoptosis in MCF-7 cells.