Simvastatin in combination with meclofenamic acid inhibits the proliferation and migration of human prostate cancer PC-3 cells via an AKR1C3 mechanism

AKR1C3 in carcinomas: from multifaceted roles to therapeutic strategies

Aldo-Keto Reductase Family 1 Member C3 (AKR1C3), also known as type 5 17β-hydroxysteroid dehydrogenase (17β-HSD5) or prostaglandin F (PGF) synthase, functions as a pivotal enzyme in androgen biosynthesis. It catalyzes the conversion of weak androgens, estrone (a weak estrogen), and PGD2 into potent androgens (testosterone and 5α-dihydrotestosterone), 17β-estradiol (a potent estrogen), and 11β-PGF2α, respectively. Elevated levels of AKR1C3 activate androgen receptor (AR) signaling pathway, contributing to tumor recurrence and imparting resistance to cancer therapies. The overexpression of AKR1C3 serves as an oncogenic factor, promoting carcinoma cell proliferation, invasion, and metastasis, and is correlated with unfavorable prognosis and overall survival in carcinoma patients. Inhibiting AKR1C3 has demonstrated potent efficacy in suppressing tumor progression and overcoming treatment resistance. As a result, the development and design of AKR1C3 inhibitors have garnered increasing interest among researchers, with significant progress witnessed in recent years. Novel AKR1C3 inhibitors, including natural products and analogues of existing drugs designed based on their structures and frameworks, continue to be discovered and developed in laboratories worldwide. The AKR1C3 enzyme has emerged as a key player in carcinoma progression and therapeutic resistance, posing challenges in cancer treatment. This review aims to provide a comprehensive analysis of AKR1C3's role in carcinoma development, its implications in therapeutic resistance, and recent advancements in the development of AKR1C3 inhibitors for tumor therapies.

Synergistic effect of a nonsteroidal anti-inflammatory drug in combination with topotecan on small cell lung cancer cells

BACKGROUND

The topoisomerase I inhibitor topotecan (TPT) is used in the treatment of recurrent small cell lung cancer (SCLC). However, the drug has a limited success rate and causes distress to patients due to its side effects, such as hematologic toxicities, including anemia and thrombocytopenia. Due to these pharmacokinetic limitations and undesirable side effects of chemotherapeutic drugs, the development of combination therapies has gained popularity in SCLC. Meclofenamic acid (MA), a nonsteroidal anti-inflammatory drug, has demonstrated anticancer effects on various types of cancers through different mechanisms. This study aims to investigate the potential synergistic effects of MA and TPT on the small cell lung cancer cell line DMS114.

METHODS AND RESULTS

To assess the cytotoxic and apoptotic effects of the combined treatment of MA and TPT, trypan blue exclusion assay, Annexin V, acridine orange/propidium iodide staining, western blot, and cell cycle analysis were conducted. The results demonstrated that the combination of MA and TPT elicited synergistic effects by enhancing toxicity in DMS114 cells (P < 0.01) without causing toxicity in healthy epithelial lung cells MRC5. The strongest synergistic effect was observed when the cells were treated with 60 µM MA and 10 nM TPT for 48 h (CI = 0,751; DRI = 10,871).

CONCLUSION

This study, for the first time, furnishes compelling evidence that MA and TPT synergistically reduce cellular proliferation and induce apoptosis in SCLC cells. Combinations of these drugs holds promise as a potential therapeutic strategy to improve efficacy and reduce the side effects associated with TPT.

Investigation of the effect of meclofenamic acid on the proteome of LNCaP cells reveals changes in alternative polyadenylation and splicing machinery

Prostate cancer is the most common type of cancer among men, and there is still no definitively effective drug treatment. Thus, the search for novel drug agents that may be used for the effective treatment continues. Meclofenamic acid (MA), a non-steroidal anti-inflammatory drug, with anti-tumor effects in various types of cancers was used to investigate its effects on LNCaP cells, a prostate cancer cell line, at the proteome level. The cells were treated with 80 µM MA for 24 h and a comparative proteomic analysis was performed with their untreated control cells. Proteins were extracted from the cells and then were subjected to two-dimensional gel electrophoresis. Protein spots displaying changes in their regulation ratios for more than two-fold were excised from the gels and identified with MALDI-TOF/TOF mass spectrometry. Bioinformatics analysis of the differentially regulated proteins that we identified showed that they were all associated with and took part in related pathways. Glycolytic pathway, cytoskeletal formation, transport activity, protein metabolism, and most notably an mRNA processing pathway were affected by the MA treatment. In addition to presenting a detailed information for what is happening inside the cells upon MA treatment, the proteins affected by MA treatment hold the potential to be novel targets for prostate cancer treatment provided that further in vivo experiments are carried out.

Double-layer omics analysis of castration- and X-ray-resistant prostate cancer cells

Castration-resistant prostate cancer shows resistance to not only androgen deprivation therapy (ADT) but also X-ray therapy. On the other hand, carbon ion beams have a high biological effect and are used for various cancers showing resistance to X-ray therapy. The purposes of this study are to clarify the difference in the sensitivity of Castration-resistant prostate cancer to X-ray and carbon ion beams and to elucidate the mechanism. The androgen-insensitive prostate cancer cell line LNCaP-LA established by culturing the androgen-sensitive prostate cancer cell line LNCaP for 2 years in androgen-free medium was used for this study. First, colony formation assays were performed to investigate its sensitivity to X-ray and carbon ion beams. Next, DNA mutation analysis on 409 cancer-related genes and comprehensive transcriptome analysis (RNA-seq) were performed with a next-generation sequencer. Lethal dose 50 values of X-rays for LNCaP and LNCaP-LA were 1.4 Gy and 2.8 Gy, respectively (P < 0.01). The Lethal dose 50 values of carbon ion beams were 0.9 Gy and 0.7 Gy, respectively (P = 0.09). On DNA mutation analysis, AR mutation was observed specifically in LNCaP-LA. From RNA-seq, 181 genes were identified as differentially expressed genes (DEGs; FDR <0.10, P < 0.00076) between LNCaP and LNCaP-LA. Function analysis suggested that cell death was suppressed in LNCaP-LA, and pathway analysis suggested that the NRF2-pathway involved in intracellular oxidative stress prevention was activated in LNCaP-LA. LNCaP-LA showed X-ray resistance compared to LNCaP and sensitivity to carbon ion beams. The AR mutation and the NRF2-pathway were suggested as causes of resistance.

A Role for ER-Beta in the Effects of Low-Density Lipoprotein Cholesterol and 27-Hydroxycholesterol on Breast Cancer Progression: Involvement of the IGF Signalling Pathway?

Cholesterol-in particular, high levels of low-density lipoprotein (LDL) and its metabolite, 27-hydroxycholesterol (27-OHC)-is correlated with increases in the risks of breast cancer and obesity. Although the high expression of LDL/27-OHC has been reported in breast cancer, its effects and mechanism of action remain to be fully elucidated. In this study, we found that the effects of LDL on cell proliferation were mediated by the activation of the cytochrome P450 enzyme, sterol 27 hydroxylase, and cholesterol 27-hydroxylase (CYP27A1) in both ER-α-positive and ER-α-negative breast cancer cells. We found that treatment with 27-OHC only increased cell growth in oestrogen receptor-α (ER-α)-positive breast cancer cells in an ER-α-dependent manner, but, interestingly, the effects of 27-OHC on cell migration and invasion were independent of ER-α. Using ER-α-negative MDA-MB-231 cells, we found that 27-OHC similarly promoted cell invasion and migration, and this was mediated by oestrogen receptor β (ER-β). These results suggest that 27-OHC promotes breast cancer cell proliferation in ER-α-positive breast cancer cells via ER-α, but migration and invasion are mediated via ER-β in ER-α positive and negative cell lines. The addition of LDL/27OHC increased the production of IGF-I and the abundance of IGF-IR in TNBC. We further found that modulating ER-β using an agonist or antagonist increased or decreased, respectively, levels of the IGF-I and EGF receptors in TNBC. The inhibition of the insulin-like growth factor receptor blocked the effects of cholesterol on cell growth and the migration of TNBC. Using TCGA and METABRIC microarray expression data from invasive breast cancer carcinomas, we also observed that higher levels of ER-beta were associated with higher levels of IGF-IR. Thus, this study shows novel evidence that ER-β is central to the effects of LDL/27OHC on invasion, migration, and the IGF and EGF axes. Our data suggest that targeting ER-β in TNBC could be an alternative approach for downregulating IGF/EGF signalling and controlling the impact of LDL in breast cancer patients.

Natural products: potential treatments for cisplatin-induced nephrotoxicity

Cisplatin is a clinically advanced and highly effective anticancer drug used in the treatment of a wide variety of malignancies, such as head and neck, lung, testis, ovary, breast cancer, etc. However, it has only a limited use in clinical practice due to its severe adverse effects, particularly nephrotoxicity; 20%–35% of patients develop acute kidney injury (AKI) after cisplatin administration. The nephrotoxic effect of cisplatin is cumulative and dose dependent and often necessitates dose reduction or withdrawal. Recurrent episodes of AKI result in impaired renal tubular function and acute renal failure, chronic kidney disease, uremia, and hypertensive nephropathy. The pathophysiology of cisplatin-induced AKI involves proximal tubular injury, apoptosis, oxidative stress, inflammation, and vascular injury in the kidneys. At present, there are no effective drugs or methods for cisplatin-induced kidney injury. Recent in vitro and in vivo studies show that numerous natural products (flavonoids, saponins, alkaloids, polysaccharide, phenylpropanoids, etc.) have specific antioxidant, anti-inflammatory, and anti-apoptotic properties that regulate the pathways associated with cisplatin-induced kidney damage. In this review we describe the molecular mechanisms of cisplatin-induced nephrotoxicity and summarize recent findings in the field of natural products that undermine these mechanisms to protect against cisplatin-induced kidney damage and provide potential strategies for AKI treatment.

Cholesterol-Lowering Drugs on Akt Signaling for Prevention of Tumorigenesis

Cholesterol has been reported to be accumulated in cancer cells. The metabolic dysregulation of the cholesterol is associated with tumor development and progression. The cholesterol-lowering drugs have been found to be involved in the prevention and treatment of various cancers. Akt, a serine/threonine kinase, can modulate the role of several downstream proteins involved in cell proliferation, migration, invasion, metabolism, and apoptosis. Since its involvement in several signaling pathways, its dysregulation is commonly reported in several cancers. Thus, targeting Akt could be an effective approach for cancer prevention and therapy. Cholesterol-lowering drugs have been found to affect the expression of Akt, and its activation in the cancer cells and thus have shown anticancer activity in different type of cancers. These drugs act on various signaling pathways such as PTEN/Akt, PI3k/Akt, Akt/NF-κB, Akt/FOXO1, Akt/mTOR, etc., which will be discussed in this article. This review article will discuss the significance of cholesterol in cancer cells, cholesterol-lowering drugs, the role of Akt in cancer cells, and the effects of cholesterol-lowering drugs on Akt in the prevention of therapy resistance and metastasis.

The role of testosterone replacement therapy and statin use, and their combination, in prostate cancer

PURPOSE

Previous studies have reported conflicting results in the associations of testosterone replacement therapy (TTh) and statins use with prostate cancer (PCa). However, the combination of these treatments with PCa stage and grade at diagnosis and prostate cancer-specific mortality (PCSM) and by race/ethnicity remains unclear.

METHODS

We identified non-Hispanic White (NHW, N = 58,576), non-Hispanic Black (NHB, n = 9,703) and Hispanic (n = 4,898) men diagnosed with PCa in SEER-Medicare data 2007-2011. Pre-diagnostic prescription of TTh and statins was ascertained for this analysis. Multivariable-adjusted logistic and Cox proportional hazards models were used to evaluate the association of TTh and statins use with PCa stage and grade and PCSM.

RESULTS

22.5% used statins alone, 1.2% used TTh alone, and 0.8% used both. TTh and statins were independently, inversely associated with PCa advanced stage and high grade. TTh plus statins was associated with 44% lower odds of advanced stage PCa (OR 0.56, 95% CI 0.35-0.91). As expected, similar inverse associations were present in NHWs as the overall cohort is mostly comprised NHW men. In Hispanic men, statin use with or without TTh was inversely associated with aggressive PCa.

CONCLUSIONS

Pre-diagnostic use of TTh or statins, independent or in combination, was inversely associated with aggressive PCa, including in NHW and Hispanics men, but was not with PCSM. The findings for use of statins with aggressive PCa are consistent with cohort studies. Future prospective studies are needed to explore the independent inverse association of TTh and the combined inverse association of TTh plus statins on fatal PCa.

Dual Inhibitory Action of a Novel AKR1C3 Inhibitor on Both Full-Length AR and the Variant AR-V7 in Enzalutamide Resistant Metastatic Castration Resistant Prostate Cancer

The expanded use of second-generation antiandrogens revolutionized the treatment landscape of progressed prostate cancer. However, resistances to these novel drugs are already the next obstacle to be solved. Various previous studies depicted an involvement of the enzyme AKR1C3 in the process of castration resistance as well as in the resistance to 2nd generation antiandrogens like enzalutamide. In our study, we examined the potential of natural AKR1C3 inhibitors in various prostate cancer cell lines and a three-dimensional co-culture spheroid model consisting of cancer cells and cancer-associated fibroblasts (CAFs) mimicking enzalutamide resistant prostate cancer. One of our compounds, named MF-15, expressed strong antineoplastic effects especially in cell culture models with significant enzalutamide resistance. Furthermore, MF-15 exhibited a strong effect on androgen receptor (AR) signaling, including significant inhibition of AR activity, downregulation of androgen-regulated genes, lower prostate specific antigen (PSA) production, and decreased AR and AKR1C3 expression, indicating a bi-functional effect. Even more important, we demonstrated a persisting inhibition of AR activity in the presence of AR-V7 and further showed that MF-15 non-competitively binds within the DNA binding domain of the AR. The data suggest MF-15 as useful drug to overcome enzalutamide resistance.

Chitosan Coated Microparticles Enhance Simvastatin Colon Targeting and Pro-Apoptotic Activity

This work aimed at improving the targeting and cytotoxicity of simvastatin (SMV) against colon cancer cells. SMV was encapsulated in chitosan polymers, followed by eudragit S100 microparticles. The release of SMV double coated microparticles was dependent on time and pH. At pH 7.4 maximum release was observed for 6 h. The efficiency of the double coat to target colonic tissues was confirmed using real-time X-ray radiography of iohexol dye. Entrapment efficiency and particle size were used in the characterization of the formula. Cytotoxicity of SMV microparticles against HCT-116 colon cancer cells was significantly improved as compared to raw SMV. Cell cycle analysis by flow cytomeric technique indicated enhanced accumulation of colon cancer cells in the G2/M phase. Additionally, a significantly higher cell fraction was observed in the pre-G phase, which highlighted enhancement of the proapoptotic activity of SMV prepared in the double coat formula. Assessment of annexin V staining was used for confirmation. Cell fraction in early, late and total cell death were significantly elevated. This was accompanied by a significant elevation of cellular caspase 3 activity. In conclusion, SMV-loaded chitosan coated with eudragit S100 formula exhibited improved colon targeting and enhanced cytotoxicity and proapoptotic activity against HCT-116 colon cancer cells.

Meclofenamic acid represses spermatogonial proliferation through modulating m6A RNA modification

Background

N6-Methyladenosine (m⁶A), the most prevalent modification in mammalian mRNA, plays important roles in numerous biological processes. Several m⁶A associated proteins such as methyltransferase like 3 (METTL3), methyltransferase like 14 (METTL14), α-ketoglutarate-dependent dioxygenase AlkB homolog 5 (ALKBH5) and YTH domain containing 2 (YTHDC2) are involved in the regulation of spermatogenesis and oogenesis. However, the role of the first detected m6A demethylase, fat mass and obesity associate protein (FTO), in germ cells remains elusive. Elucidation of FTO roles in the regulation of germ cell fate will provide novel insights into the mammalian reproduction.

Methods

Mouse GC-1 spg cells were treated with the ester form of meclofenamic acid (MA2) to inhibit the demethylase activity of FTO. The cellular m⁶A and m⁶A_m level were analyzed through high performance liquid chromatography combined with tandem mass spectrometry (HPLC/MS-MS). The cell apoptosis was detected via TUNEL and flow cytometry. The cell proliferation was detected through EdU and western blot. The mRNA level of core cyclin dependent kinases (CDKs) was quantified via q-PCR. RNA decay assay were performed to detect RNA stability. Dual fluorescence assay was conducted to study whether MA2 affects the expression of CDK2 dependent on the m⁶A modification at 3’UTR.

Results

MA2 significantly increased the cellular m⁶A level and down-regulated the expression of CDK1, CDK2, CDK6 and CdC25a, resulting in arrest of G1/S transition and decrease of cell proliferation. MA2 downregulated CDK2 mRNA stability. Additionally, mutation of the predicted m⁶A sites in the Cdk2–3’UTR could mitigated the degradation of CDK2 mRNA after MA2 treatment.

Conclusion

MA2 affected CDKs expression through the m⁶A-dependent mRNA degradation pathway, and thus repressed spermatogonial proliferation.

Electronic supplementary material

The online version of this article (10.1186/s40104-019-0361-6) contains supplementary material, which is available to authorized users.

Herceptin-conjugated liposomes co-loaded with doxorubicin and simvastatin in targeted prostate cancer therapy

Prostate cancer (PCa) is a leading cause of cancer-related deaths among men. The anthracycline doxorubicin (DOX) is used for the treatment of this disease, but its considerable side effects and non-selectivity are major drawbacks. Simvastatin (Sim), a lipid-lowering agent, holds great promise as a cancer therapeutic, and thus could be used in combination with DOX. Targeted drug-loaded nano-carriers with antibodies for receptors that are overexpressed on tumor cells are promising strategies for decreasing toxicity to normal tissues and enhancing the efficacy of chemotherapies in cancer treatment. Specifically, human epidermal growth factor 2 is overexpressed and constitutively activated in the PC-3 cell line. Within this context, we designed a co-delivery system coated with Herceptin for PCa, performed physicochemical characterizations, and tested the formulations for cytotoxicity and uptake. The targeted liposomes had a mean particle size of 134 nm, and the drug encapsulation efficiency of both Sim and DOX were greater than 80%. We discovered that the drug combination led to the strong inhibition of PCa both in vitro and in vivo, with inhibitory rates of tumor volumes corresponding to 80.36% and 68.77% of Herceptin-coated liposomes and non-targeted liposomes, respectively. We also found that the anti-tumor mechanisms of the DOX and Sim combination were possibly attributed to synergistic anti-angiogenesis. These results reveal that Herceptin-conjugated liposomes co-loaded with DOX and Sim are a potential novel therapeutic strategy for overcoming PCa.

Cholesterol and Its Metabolites in Tumor Growth: Therapeutic Potential of Statins in Cancer Treatment

Cholesterol is essential for cell function and viability. It is a component of the plasma membrane and lipid rafts and is a precursor for bile acids, steroid hormones, and Vitamin D. As a ligand for estrogen-related receptor alpha (ESRRA), cholesterol becomes a signaling molecule. Furthermore, cholesterol-derived oxysterols activate liver X receptors (LXRs) or estrogen receptors (ERs). Several studies performed in cancer cells reveal that cholesterol synthesis is enhanced compared to normal cells. Additionally, high serum cholesterol levels are associated with increased risk for many cancers, but thus far, clinical trials with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have had mixed results. Statins inhibit cholesterol synthesis within cells through the inhibition of HMG-CoA reductase, the rate-limiting enzyme in the mevalonate and cholesterol synthetic pathway. Many downstream products of mevalonate have a role in cell proliferation, since they are required for maintenance of membrane integrity; signaling, as some proteins to be active must undergo prenylation; protein synthesis, as isopentenyladenine is an essential substrate for the modification of certain tRNAs; and cell-cycle progression. In this review starting from recent acquired findings on the role that cholesterol and its metabolites fulfill in the contest of cancer cells, we discuss the results of studies focused to investigate the use of statins in order to prevent cancer growth and metastasis.