Inhibition of IL-6 expression in LNCaP prostate cancer cells by a combination of atorvastatin and celecoxib

The Potential Preventive and Therapeutic Roles of NSAIDs in Prostate Cancer

Prostate cancer (PC) is the second most common type of cancer and the leading cause of death among men worldwide. Preventing the progression of cancer after treatments such as radical prostatectomy, radiation therapy, and hormone therapy is a major concern faced by prostate cancer patients. Inflammation, which can be caused by various factors such as infections, the microbiome, obesity and a high-fat diet, is considered to be the main cause of PC. Inflammatory cells are believed to play a crucial role in tumor progression. Therefore, nonsteroidal anti-inflammatory drugs along with their effects on the treatment of inflammation-related diseases, can prevent cancer and its progression by suppressing various inflammatory pathways. Recent evidence shows that nonsteroidal anti-inflammatory drugs are effective in the prevention and treatment of prostate cancer. In this review, we discuss the different pathways through which these drugs exert their potential preventive and therapeutic effects on prostate cancer.

Novel mucoadhesive celecoxib-loaded cubosomal sponges: Anticancer potential and regulation of myeloid-derived suppressor cells in oral squamous cell carcinoma

Oral squamous-cell carcinoma (OSCC) is a widespread health problem. Myeloid-derived suppressor cells (MDSCs) are major tumor microenvironment (TME) population that govern many carcinogenesis aspects by establishing immunosuppressive milieu favoring tumor aggressiveness and treatment resistance. Cyclooxygenase-2 (COX-2) regulates MDSCs activity, hence, COX-2-selective inhibition by celecoxib (CXB) showed good anticancer effect at relatively high doses with possible subsequent cardiovascular complications. Therefore, targeted CXB delivery to MDSCs may represent a promising OSCC treatment strategy. Novel mucoadhesive-cubosomal buccal sponges were prepared for MDSCs targeting and were evaluated for their in-vitro quality attributes, ex-vivo mucoadhesion using buccal chicken-mucosa. Optimally-selected formulation showed considerable uptake by CD33⁺/11b⁺MDSCs in human OSCC cell-line (SCC-4) when quantitatively analyzed by flow-cytometry and examined using confocal-laser microscope. Optimum formulations loaded with low CXB doses (12 mg) were promoted to in-vivo studies via local application, using 4-nitroquinoline-1-oxide-induced OSCC in rats, and compared to their corresponding CXB gels. SP16 revealed the highest ability to decrease MDSC activation, recruitment and TME-immunosuppression in the isolated tumors. Consequently, SP16 exerted the greatest capacity to reduce histologic tumor grade, the OSCC-specific serum tumor markers levels, cancer hallmarks and stemness markers. CXB-loaded cubosomal sponges preferentially target MDSCs with noticeable anticancer potential and may exemplify novel mucoadhesive nanocarriers for OSCC treatment.

NSAIDs: Old Acquaintance in the Pipeline for Cancer Treatment and Prevention─Structural Modulation, Mechanisms of Action, and Bright Future

The limitations of current chemotherapeutic drugs are still a major issue in cancer treatment. Thus, targeted multimodal therapeutic approaches need to be strategically developed to successfully control tumor growth and prevent metastatic burden. Inflammation has long been recognized as a hallmark of cancer and plays a key role in the tumorigenesis and progression of the disease. Several epidemiological, clinical, and preclinical studies have shown that traditional nonsteroidal anti-inflammatory drugs (NSAIDs) exhibit anticancer activities. This Perspective reports the most recent outcomes for the treatment and prevention of different types of cancers for several NSAIDs alone or in combination with current chemotherapeutic drugs. Furthermore, an extensive review of the most promising structural modifications is reported, such as phospho, H₂S, and NO releasing-, selenium-, metal complex-, and natural product-NSAIDs, among others. We also provide a perspective about the new strategies used to obtain more efficient NSAID- or NSAID derivative- formulations for targeted delivery.

Inhibition of Scavenger Receptor Class B Type 1 (SR-B1) Expression and Activity as a Potential Novel Target to Disrupt Cholesterol Availability in Castration-Resistant Prostate Cancer

There have been several studies that have linked elevated scavenger receptor class b type 1 (SR-B1) expression and activity to the development and progression of castration-resistant prostate cancer (CRPC). SR-B1 facilitates the influx of cholesterol to the cell from lipoproteins in systemic circulation. This influx of cholesterol may be important for many cellular functions, including the synthesis of androgens. Castration-resistant prostate cancer tumors can synthesize androgens de novo to supplement the loss of exogenous sources often induced by androgen deprivation therapy. Silencing of SR-B1 may impact the ability of prostate cancer cells, particularly those of the castration-resistant state, to maintain the intracellular supply of androgens by removing a supply of cholesterol. SR-B1 expression is elevated in CRPC models and has been linked to poor survival of patients. The overarching belief has been that cholesterol modulation, through either synthesis or uptake inhibition, will impact essential signaling processes, impeding the proliferation of prostate cancer. The reduction in cellular cholesterol availability can impede prostate cancer proliferation through both decreased steroid synthesis and steroid-independent mechanisms, providing a potential therapeutic target for the treatment of prostate cancer. In this article, we discuss and highlight the work on SR-B1 as a potential novel drug target for CRPC management.

An organotin indomethacin derivative inhibits cancer cell proliferation and synergizes the antiproliferative effects of lapatinib in breast cancer cells

It is known that an inflammatory condition in different types of cancer provides a sustained microenvironment that favors tumor growth, invasion, and metastasis. Non-steroidal anti-inflammatory drugs such as indomethacin have demonstrated chemo-preventive, anti-proliferative and cytotoxic effects in a variety of tumors. The aim of this study was to investigate the effects of an organotin indomethacin derivative (OID) on the proliferation of breast and prostate cancer cell lines and the possible mechanisms of action of this compound. Different cancer cell lines were treated in the presence of OID and cell proliferation was measured by quantification of the DNA content, changes in the cell cycle profile and the activation of caspase 3 were evaluated by flow cytometry, interleukin 6 (IL-6) gene expression was evaluated by qPCR and protein expression was analyzed by ELISA and Western blot assays. OID inhibited the cell proliferation of a panel of cancer cell lines in a concentration-dependent manner. Moreover, the addition of OID to lapatinib treatment, targeted therapy for breast cancer, significantly enhanced its antiproliferative response. The effects on cell proliferation of these compounds involved, among others, the induction of apoptosis, the downregulation of IL-6 and a decrease of the MAPK activation pathway. Our results suggest that the use of OID alone or in combination with tyrosine kinase inhibitors could be considered as adjuvants in the treatment of cancer.

Sprouty2 loss-induced IL6 drives castration-resistant prostate cancer through scavenger receptor B1

Metastatic castration-resistant prostate cancer (mCRPC) is a lethal form of treatment-resistant prostate cancer and poses significant therapeutic challenges. Deregulated receptor tyrosine kinase (RTK) signalling mediated by loss of tumour suppressor Sprouty2 (SPRY2) is associated with treatment resistance. Using pre-clinical human and murine mCRPC models, we show that SPRY2 deficiency leads to an androgen self-sufficient form of CRPC Mechanistically, HER2-IL6 signalling axis enhances the expression of androgen biosynthetic enzyme HSD3B1 and increases SRB1-mediated cholesterol uptake in SPRY2-deficient tumours. Systemically, IL6 elevated the levels of circulating cholesterol by inducing host adipose lipolysis and hepatic cholesterol biosynthesis. SPRY2-deficient CRPC is dependent on cholesterol bioavailability and SRB1-mediated tumoral cholesterol uptake for androgen biosynthesis. Importantly, treatment with ITX5061, a clinically safe SRB1 antagonist, decreased treatment resistance. Our results indicate that cholesterol transport blockade may be effective against SPRY2-deficient CRPC.

In-vitro and in-vivo inhibition of melanoma growth and metastasis by the drug combination of celecoxib and dacarbazine

Celecoxib has been found to be effective in cancer prevention and treatment. Its combination with other chemotherapeutic agents was reported to produce synergistic/additive effects on various cancers. Dacarbazine (DTIC) is one of the most commonly used drugs in the treatment of metastatic melanoma. This investigation aimed to determine the in-vitro and in-vivo effects of the drug combination of celecoxib and DTIC on melanoma growth and metastasis. Melanoma cells B16-F10 and SK-MEL-28, and female C57BL/6 mice were used for the study. Our in-vitro data showed that significant synergistic effects were obtained when celecoxib was used together with various concentrations of DTIC. A study with B16-F10 cells using flow cytometry analysis showed that the drug combination induced significantly more apoptosis than each drug used individually. Our in-vivo results showed that the drug combination was much more effective than each drug used alone for the inhibition of both melanoma growth and metastasis in the B16-F10+C57BL/6 mouse models. For melanoma growth, the median survival rates for phosphate-buffered saline (PBS) (control), celecoxib (30 mg/kg), DTIC-1 (10 mg/kg), DTIC-2 (positive control, 50 mg/kg), and the drug combination (DTIC 10 mg/kg+celecoxib 30 mg/kg) were 6, 6.5, 7.5, 7.5, and 9 days, respectively. For melanoma metastasis, the average number of metastatic tumors in murine lungs was 53.7±10.7, 31.8±18.6, 21.2±21.7, 7.0±9.0, and 0.8±2.0 for PBS, DTIC-1, celecoxib, the drug combination, and DTIC-2. Our results warrant further investigation of the combination as an effective treatment for melanoma patients.

Phenethyl isothiocyanate in combination with dibenzoylmethane inhibits the androgen-independent growth of prostate cancer cells

This study investigates the inhibitory effect of PEITC and DBM in combination on the progression of androgen-dependent VCaP prostate tumors to androgen independence.

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

Statins have become of interest in research due to their anticancer effects. However, the exact mechanism of their anticancer properties remains unclear. The authors previously reported that statins decrease intracellular cholesterol levels in androgen-independent prostate cancer cells. In de novo androgen synthesis, cholesterol is the primary material and certain enzymes have important roles. The present study aimed to determine whether simvastatin alters the expression of androgen synthesis-associated enzymes in androgen-independent prostate cancer cells. A novel combination therapy of statins and other drugs that inhibit the overexpression of enzymes involved in androgen synthesis was explored. The cytotoxicity of simvastatin and meclofenamic acid was assessed in prostate cancer cells using MTS and migration assays. Testosterone and dihydrotestosterone concentrations in the culture medium were measured using liquid chromatography-tandem mass spectrometry. RAC-α-serine/threonine-protein kinase (Akt) phosphorylation was detected by western blot analysis. Following treatment with simvastatin, aldo-keto reductase family 1 member C3 (AKR1C3) expression increased in PC-3 (>60-fold) and LNCaP-LA cells, however not in 22Rv1 cells. Small interfering (si)RNA was used to clarify the effects of AKR1C3 expression. The reduction in AKR1C3 expression in PC-3 cells following siRNA transfection was not associated with basal cell proliferation and migration; however, treatment with simvastatin decreased cell proliferation and migration. The combination of simvastatin and meclofenamic acid, an AKR1C3 inhibitor, further enhanced the inhibition of cell proliferation and migration compared with treatment with either drug alone. Furthermore, treatment with simvastatin attenuated insulin-like growth factor 1-induced Akt activation; however, the combination of simvastatin and meclofenamic acid further inhibited Akt activation. These results suggest that the combination of simvastatin and meclofenamic acid may be an effective strategy for the treatment of castration-resistant prostate cancer.

Atorvastatin improves coronary flow and endothelial function in patients with coronary slow flow

The underlying mechanisms behind the effect of atorvastatin on patients with coronary slow flow (CSF) remain largely unknown. To investigate the possible underlying molecular mechanisms 108 patients were divided into atorvastatin group and control group. Coronary flow was quantified according to corrected TIMI frame count (CTFC). Serum high sensitivity C-reactive protein (hs-CRP), lipids, ET-1, interleukin (IL)-6, NO, circulating endothelial progenitor cell (cEPC) count, adhesion, migration and proliferation were measured in pretreatment and post-treatment. After respective treatment, the atorvastatin group had significantly decreased levels of TC, TG, LDL-C, hs-CRP, ET-1 and IL-6 and increased NO compared to the control group. The atorvastatin group had a more significant improvement of CTFC, effective rate, cEPC number, EPC adhesion, migration and proliferation compared to the control group. In conclusion, atorvastatin can be used in treatment of CSF by suppressing inflammation and improving endothelial function.

Cancer Chemotherapy Specific to Acidic Nests

The realization of cancer therapeutics specific to cancer cells with less of an effect on normal tissues is our goal. Many trials have been carried out for this purpose, but this goal is still far from being realized. It was found more than 80 years ago that solid cancer nests are acidified, but in vitro studies under acidic conditions have not been extensively studied. Recently, in vitro experiments under acidic conditions were started and anti-cancer drugs specific to acidic areas have been identified. Many genes have been reported to be expressed at a high level under acidic conditions, and such genes may be potent targets for anti-cancer drugs specific to acidic nests. In this review article, recent in vitro, in vivo, and clinical achievements in anti-cancer drugs with marked efficacy under acidic conditions are summarized, and the clinical use of anti-cancer drugs specific to acidic nests is discussed.

Hitting the Bull's-Eye in Metastatic Cancers-NSAIDs Elevate ROS in Mitochondria, Inducing Malignant Cell Death

Tumor metastases that impede the function of vital organs are a major cause of cancer related mortality. Mitochondrial oxidative stress induced by hypoxia, low nutrient levels, or other stresses, such as genotoxic events, act as key drivers of the malignant changes in primary tumors to enhance their progression to metastasis. Emerging evidence now indicates that mitochondrial modifications and mutations resulting from oxidative stress, and leading to OxPhos stimulation and/or enhanced reactive oxygen species (ROS) production, are essential for promoting and sustaining the highly metastatic phenotype. Moreover, the modified mitochondria in emerging or existing metastatic cancer cells, by their irreversible differences, provide opportunities for selectively targeting their mitochondrial functions with a one-two punch. The first blow would block their anti-oxidative defense, followed by the knockout blow—promoting production of excess ROS, capitulating the terminal stage—activation of the mitochondrial permeability transition pore (mPTP), specifically killing metastatic cancer cells or their precursors. This review links a wide area of research relevant to cellular mechanisms that affect mitochondria activity as a major source of ROS production driving the pro-oxidative state in metastatic cancer cells. Each of the important aspects affecting mitochondrial function are discussed including: hypoxia, HIFs and PGC1 induced metabolic changes, increased ROS production to induce a more pro-oxidative state with reduced antioxidant defenses. It then focuses on how the mitochondria, as a major source of ROS in metastatic cancer cells driving the pro-oxidative state of malignancy enables targeting drugs affecting many of these altered processes and why the NSAIDs are an excellent example of mitochondria-targeted agents that provide a one-two knockout activating the mPTP and their efficacy as selective anticancer metastasis drugs.

Combination of Lipitor and Celebrex inhibits prostate cancer VCaP cells in vitro and in vivo

BACKGROUND/AIM

Lipitor is a cholesterol-lowering drug and Celebrex is a Cyclooxygenase-2 inhibitor. We investigated the effects of Lipitor and Celebrex on human prostate cancer VCaP cells cultured in vitro and grown as orthotopic xenograft tumors in SCID mice.

MATERIALS AND METHODS

Apoptosis was measured by morphological assessment and caspase-3 assay. Nuclear factor-kappa B (NF-κB) activation was determined by luciferase reporter assay. B-cell lymphoma-2 (Bcl2) was measured by western blotting and immunohistochemistry. Orthotopic prostate tumors were monitored by the IVIS imaging system.

RESULTS

the combination of Lipitor and Celebrex had stronger effects on the growth and apoptosis of VCaP cells than did either drug alone. The combination more potently inhibited activation of NFκB and expression of Bcl2 than either drug alone. The growth of orthotopic VCaP prostate tumors was strongly inhibited by treatment with the drug combination.

CONCLUSION

Administration of Lipitor and Celebrex in combination may be an effective strategy for inhibiting the growth of prostate cancer.