Metformin and Prostate Cancer: a New Role for an Old Drug

Recent advances in dietary androgen receptor inhibitors

As a nuclear transcription factor, the androgen receptor (AR) plays a crucial role not only in normal male sexual differentiation and growth of the prostate, but also in benign prostatic hyperplasia, prostatitis, and prostate cancer. Multiple population-based epidemiological studies demonstrated that prostate cancer risk was inversely associated with increased dietary intakes of green tea, soy products, tomato, and so forth. Therefore, this review aimed to summarize the structure and function of AR, and further illustrate the structural basis for antagonistic mechanisms of the currently clinically available antiandrogens. Due to the limitations of these antiandrogens, a series of natural AR inhibitors have been identified from edible plants such as fruits and vegetables, as well as folk medicines, health foods, and nutritional supplements. Hence, this review mainly focused on recent experimental, epidemiological, and clinical studies about natural AR inhibitors, particularly the association between dietary intake of natural antiandrogens and reduced risk of prostatic diseases. Since natural products offer multiple advantages over synthetic antiandrogens, this review may provide a comprehensive and updated overview of dietary-derived AR inhibitors, as well as their potential for the nutritional intervention against prostatic disorders.

Metformin-induced oxidative stress inhibits LNCaP prostate cancer cell survival

BACKGROUND

Preclinical and clinical studies over the past several decades have indicated the potential value of metformin, a widely utilized treatment for Type 2 diabetes, in prostate cancer therapy. Notably, these studies demonstrated metformin's pleiotropic effects on several molecular and metabolic pathways, such as androgen signaling, cell cycle, and cellular bioenergetics. In this study we investigated the role of metformin in regulating intracellular redox status and cell survival in LNCaP prostate cancer cells.

METHODS AND RESULTS

The cytotoxic effects of metformin with or without the presence of SBI0206965 (AMPK inhibitor) on LNCaP cells were determined using MTT and trypan blue exclusion assays. Seahorse XP extracellular analysis, Liquid Chromatography/ Mass Spectrophotometry (LC/MS), and 2,7- and Dichlorofluoresin diacetate (DCFDA) assay were used to assess the effects of metformin on cellular bioenergetics, redox status, and redox-related metabolites. mRNA expression and protein concentration of redox-related enzymes were measured using Real Time-qPCR and ELISA assay, respectively. Independently of AMP-activated protein kinase, metformin exhibited a dose- and time-dependent inhibition of LNCaP cell survival, a response mitigated by glutathione or N-acetylcysteine (ROS scavengers) treatment. Notably, these findings were concomitant with a decline in ATP levels and the inhibition of oxidative phosphorylation. The results further indicated metformin's induction of reactive oxygen species, which significantly decreased glutathione levels and the ratio of reduced to oxidized glutathione, as well as the transsulfuration metabolite, cystathionine. Consistent with an induction of oxidative stress condition, metformin increased mRNA levels of the master redox transcription factor Nrf-2 (nuclear factor erythroid-derived 2-like), as well as transsulfuration enzymes cystathionine beta-synthase and cystathionase and GSH synthesis enzymes γ-glutamylcysteine synthetase and glutathione synthetase.

CONCLUSION

Our findings highlight multiple mechanisms by which metformin-induced formation of reactive oxygen species may contribute to its efficacy in prostate cancer treatment, including promotion of oxidative stress, Nrf2 activation, and modulation of redox-related pathways, leading to its anti-survival action.

Incidence and risk factors of prostate cancer among the Northern and Eastern parts of the United Arab Emirates population

BACKGROUND

Prostate cancer (PCa) is a prevalent disease worldwide. However, the incidence and patient-specific risk factors of PCa in the Middle East, specifically in the United Arab Emirates, have not been previously reported.

METHODS

We conducted a retrospective cohort study on 2377 men diagnosed with either benign prostatic hyperplasia (BPH) or PCa in the Northern and Eastern regions of the United Arab Emirates, excluding the Western part, which includes Abu Dhabi. The study spanned from January 2012 and December 2021. To calculate the PCa incidence rate, we utilized the world age-standardized incidence rates (W-ASIR) categorized by age groups. Patient-specific risk factors of PCa were identified through a multivariate logistic regression analysis of clinical data.

RESULTS

A total of 247 cases of PCa and 2130 cases of BPH were included in the study. In our cohort, the W-ASIR for PCa was 21.3 per 100,000 men. The incidence of PCa showed an increasing trend with age, with the highest incidence observed among men aged 70 years and older. Accordingly, multivariate analysis revealed that age over 70 was associated with an increased risk of PCa (OR: 2.546, 95% confidence interval [CI]: 1.892-3.425, p < 0.01). On the other hand, preexisting conditions such as hypertension and diabetes mellitus were found to lower the risk of PCa (OR: 0.222, 95% CI: 0.163-0.302, p < 0.001) and (OR: 0.364, 95% CI: 0.205-0.648, p < 0.001), respectively. Additionally, metformin intake was associated with a reduced risk of PCa (OR: 0.385, 95% CI: 0.190-0.782, p = 0.008); while insulin usage increased the risk of PCa (OR: 2.586, 95% CI: 1.539-4.344, p < 0.001). Anti-BPH medications such as phosphodiesterase inhibitors (OR: 0.223, 95% CI: 0.069-0.723, p = 0.012) or 5-α reductase (OR: 0.206, 95% CI: 0.110-0.389, p < 0.000), were found to lower the risk of PCa.

CONCLUSION

The findings underscore the high incidence of PCa in the United Arab Emirates, with age being a significant factor. Furthermore, the study highlights the influence of certain comorbidities and medications on the risk of developing PCa within the United Arab Emirates population.

Oxidative brain and cerebellum injury in diabetes and prostate cancer model: Protective effect of metformin

The body can host the spread of prostate cancer cells. Metastases from prostate cancer are more frequently seen in the brain, liver, lungs, and lymph nodes. A well-known antidiabetic drug, metformin, is also known to have antitumor effects. Our study focuses on the evaluation of potential metformin protective effects on brain and cerebellum damage in streptozotocin (STZ)-induced diabetic and Dunning prostate cancer models. In this investigation, six groups of male Copenhagen rats were created: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin, and diabetic + cancer + metformin. The brain and cerebellum tissues of the rats were taken after sacrifice. Oxidative stress markers including reduced glutathione level, lipid peroxidation, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, catalase, superoxide dismutase activities, reactive oxygen species, total oxidant and total antioxidant status, lactate dehydrogenase, xanthine oxidase, acetylcholinesterase activities, protein carbonyl contents, nitric oxide and OH-proline levels, sodium potassium ATPase, carbonic anhydrase, and glucose-6-phosphate dehydrogenase activities; glycoprotein levels including hexose, hexosamine, fucose, and sialic acid levels; and histone deacetylase activity as a cancer marker were determined. Oxidative stress markers were impaired and glycoprotein levels and histone deacetylase activity were increased in the D, C, and DC groups. Metformin therapy reversed these effects. Metformin was found to protect the brain and cerebellum of STZ-induced diabetic rats with Dunning prostate cancer from harm caused by MAT-Lylu metastatic cells.

Utilizing metformin to prevent metabolic syndrome due to androgen deprivation therapy (ADT): a randomized phase II study of metformin in non-diabetic men initiating ADT for advanced prostate cancer

BACKGROUND

Androgen deprivation therapy (ADT) can lead to metabolic syndrome (MS) and is implicated in ADT-resistance. Metformin showed antineoplastic activity through mTOR inhibition secondary AMPK-activation.

MATERIALS AND METHODS

To investigate whether metformin mitigated ADT-related MS, we conducted a randomized double-blind phase II trial of metformin 500 mg TID or placebo in non-diabetic patients with biochemically-relapsed or advanced PC due for ADT. Fasting serum glucose, insulin, PSA, metformin, weight and waist circumference (WC) were measured at baseline, week 12 and 28. The primary endpoint was a group of MS metrics. Secondary endpoints include PSA response, safety, serum metformin concentrations and analysis of downstream an mTOR target, phospho-S6-kinase.

RESULTS

36 men were randomized to either metformin or placebo. Mean age was 68.4. Mean weight, WC and insulin levels increased in both arms. At week 12 and 28, no statistical differences in weight, WC or insulin were observed in either arm. No significant difference in percentage of patients with PSA <0.2 at week 28 between metformin (45.5%) vs. placebo (46.7%). Analysis in the metformin-arm showed variable down-regulation of phospho-S6 kinase.

CONCLUSIONS

In our small study, metformin added to ADT did not show a reduced risk of ADT-related MS or differences in PSA response.

A phase II, open-label, non-randomized, prospective study assessing paclitaxel, carboplatin and metformin in the treatment of advanced stage ovarian carcinoma

OBJECTIVE

The purpose of this study was to assess the efficacy and tolerability of a paclitaxel, carboplatin and metformin regimen in the first-line treatment of advanced-stage ovarian, fallopian tube, and primary peritoneal carcinoma.

METHODS

Eligible subjects underwent surgery and 6 cycles of neoadjuvant or adjuvant dose-dense intravenous paclitaxel (80 mg/m²), carboplatin (area under the curve 5 or 6 on Day 1), and oral metformin (850 mg daily). Study participants who completed their primary therapy and attained a clinically defined complete or partial response (PR) were treated with a planned 12 cycles of paclitaxel (135 mg/m² every 21 days) and metformin (850 mg twice daily) maintenance therapy.

RESULTS

Thirty subjects received a median of 6 cycles (range, 5-6) of primary induction chemotherapy and were eligible for response evaluation; twenty-three patients exhibited a complete response, while 3 study patients obtained a PR (an overall response rate of 86.7%). Grade 3-4 hematological toxicity included neutropenia (43.3%), thrombocytopenia (10%) and anemia (36.7%). There was no incidence of grade 3-4 neuropathy although 15 patients (50%) developed grade ≤2 neurotoxicity. Additionally, we observed grade ≤2 diarrhea in 20 (66.7%) subjects. The median progression-free survival was 21 months (range, 3-52) and overall median survival was 35 months (range, 15-61). The subjects also received an aggregate 103 cycles (median, 12; range, 6-12) of maintenance chemotherapy.

CONCLUSION

The study results suggest that the combination of paclitaxel, carboplatin and metformin is associated with moderate efficacy and a reasonable toxicity profile.

TNK2/ACK1-mediated phosphorylation of ATP5F1A (ATP synthase F1 subunit alpha) selectively augments survival of prostate cancer while engendering mitochondrial vulnerability

The challenge of rapid macromolecular synthesis enforces the energy-hungry cancer cell mitochondria to switch their metabolic phenotypes, accomplished by activation of oncogenic tyrosine kinases. Precisely how kinase activity is directly exploited by cancer cell mitochondria to meet high-energy demand, remains to be deciphered. Here we show that a non-receptor tyrosine kinase, TNK2/ACK1 (tyrosine kinase non receptor 2), phosphorylated ATP5F1A (ATP synthase F1 subunit alpha) at Tyr243 and Tyr246 (Tyr200 and 203 in the mature protein, respectively) that not only increased the stability of complex V, but also increased mitochondrial energy output in cancer cells. Further, phospho-ATP5F1A (p-Y-ATP5F1A) prevented its binding to its physiological inhibitor, ATP5IF1 (ATP synthase inhibitory factor subunit 1), causing sustained mitochondrial activity to promote cancer cell growth. TNK2 inhibitor, (R)-9b reversed this process and induced mitophagy-based autophagy to mitigate prostate tumor growth while sparing normal prostate cells. Further, depletion of p-Y-ATP5F1A was needed for (R)-9b-mediated mitophagic response and tumor growth. Moreover, Tnk2 transgenic mice displayed increased p-Y-ATP5F1A and loss of mitophagy and exhibited formation of prostatic intraepithelial neoplasia (PINs). Consistent with these data, a marked increase in p-Y-ATP5F1A was seen as prostate cancer progressed to the malignant stage. Overall, this study uncovered the molecular intricacy of tyrosine kinase-mediated mitochondrial energy regulation as a distinct cancer cell mitochondrial vulnerability and provided evidence that TNK2 inhibitors can act as "mitocans" to induce cancer-specific mitophagy.Abbreviations: ATP5F1A: ATP synthase F1 subunit alpha; ATP5IF1: ATP synthase inhibitory factor subunit 1; CRPC: castration-resistant prostate cancer; DNM1L: dynamin 1 like; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; Mdivi-1: mitochondrial division inhibitor 1; Mut-ATP5F1A: Y243,246A mutant of ATP5F1A; OXPHOS: oxidative phosphorylation; PC: prostate cancer; PINK1: PTEN induced kinase 1; p-Y-ATP5F1A: phosphorylated tyrosine 243 and 246 on ATP5F1A; TNK2/ACK1: tyrosine kinase non receptor 2; Ub: ubiquitin; WT: wild type.

Synergistic Effect of Metformin and Lansoprazole Against Gastric Cancer through Growth Inhibition

Cancer has been linked to metabolic disorders and diverse gene mutations. Metformin, which is widely used to treat type 2 diabetes, inhibits the growth of cancer cells in animal models. Here we investigated the effects of metformin on human gastric cancer cell lines. We also investigated the synergistic anticancer effect of metformin and proton pump inhibitors. Lansoprazole, a proton pump inhibitor, is effective for treating gastroesophageal reflux disease. Our results revealed that metformin and lansoprazole can significantly inhibit cancer cell growth in a dose-dependent manner by suppressing cell cycle progression and inducing apoptosis. Low concentrations of metformin and lansoprazole have a synergistic effect on AGS cell growth inhibition. In summary, our findings suggest a new and safe treatment protocol for treating stomach cancers.

Prostate cancer cells demonstrate unique metabolism and substrate adaptability acutely after androgen deprivation therapy

BACKGROUND

Androgen deprivation therapy (ADT) has been the standard of care for advanced hormone-sensitive prostate cancer (PC), yet tumors invariably develop resistance resulting in castrate-resistant PC. The acute response of cancer cells to ADT includes apoptosis and cell death, but a large fraction remains arrested but viable. In this study, we focused on intensively characterizing the early metabolic changes that result after ADT to define potential metabolic targets for treatment.

METHODS

A combination of mass spectrometry, optical metabolic imaging which noninvasively measures drug responses in cells, oxygen consumption rate, and protein expression analysis was used to characterize and block metabolic pathways over several days in multiple PC cell lines with variable hormone response status including ADT sensitive lines LNCaP and VCaP, and resistant C4-2 and DU145.

RESULTS

Mass spectrometry analysis of LNCaP pre- and postexposure to ADT revealed an abundance of glycolytic intermediates after ADT. In LNCaP and VCaP, a reduction in the optical redox ratio [NAD(P)H/FAD], extracellular acidification rate, and a downregulation of key regulatory enzymes for fatty acid and glutamine utilization was acutely observed after ADT. Screening several metabolic inhibitors revealed that blocking fatty acid oxidation and synthesis reversed this stress response in the optical redox ratio seen with ADT alone in LNCaP and VCaP. In contrast, both cell lines demonstrated increased sensitivity to the glycolytic inhibitor 2-Deoxy- d-glucose(2-DG) and maintained sensitivity to electron transport chain inhibitor Malonate after ADT exposure. ADT followed by 2-DG results in synergistic cell death, a result not seen with simultaneous administration.

CONCLUSIONS

Hormone-sensitive PC cells displayed altered metabolic profiles early after ADT including an overall depression in energy metabolism, induction of a quiescent/senescent phenotype, and sensitivity to selected metabolic inhibitors. Glycolytic blocking agents (e.g., 2-DG) as a sequential treatment after ADT may be promising.

Cancer as a biophysical disease: Targeting the mechanical-adaptability program

With the number of cancer cases projected to significantly increase over time, researchers are currently exploring "nontraditional" research fields in the pursuit of novel therapeutics. One emerging area that is steadily gathering interest revolves around cellular mechanical machinery. When looking broadly at the physical properties of cancer, it has been debated whether a cancer could be defined as either stiffer or softer across cancer types. With numerous articles supporting both sides, the evidence instead suggests that cancer is not particularly regimented. Instead, cancer is highly adaptable, allowing it to endure the constantly changing microenvironments cancer cells encounter, such as tumor compression and the shear forces in the vascular system and body. What allows cancer cells to achieve this adaptability are the particular proteins that make up the mechanical network, leading to a particular mechanical program of the cancer cell. Coincidentally, some of these proteins, such as myosin II, α-actinins, filamins, and actin, have either altered expression in cancer and/or some type of direct involvement in cancer progression. For this reason, targeting the mechanical system as a therapeutic strategy may lead to more efficacious treatments in the future. However, targeting the mechanical program is far from trivial. As involved as the mechanical program is in cancer development and metastasis, it also helps drive many other key cellular processes, such as cell division, cell adhesion, metabolism, and motility. Therefore, anti-cancer treatments targeting the mechanical program must take great care to avoid potential side effects. Here, we introduce the potential of targeting the mechanical program while also providing its challenges and shortcomings as a strategy for cancer treatment.

Association between baseline body mass index and survival in men with metastatic hormone-sensitive prostate cancer: ECOG-ACRIN CHAARTED E3805

BACKGROUND

E3805 (CHAARTED) is a phase 3 trial demonstrating improved survival for men with metastatic hormone-sensitive prostate cancer (mHSPC) randomized to treatment with docetaxel (D) and androgen-deprivation therapy (ADT) versus ADT alone. We assessed the association of baseline body mass index (BMI) and metformin exposure with quality of life (QOL) and prostate cancer outcomes including survival in patients enrolled in the CHAARTED study.

METHODS

We performed a posthoc exploratory analysis of the CHAARTED trial of men with mHSPC randomized to treatment with ADT with or without D between 2006 and 2012. Cox proportional hazards models and Kruskal-Wallis test were used to evaluate the association between BMI with QOL and prostate cancer outcomes and between metformin exposure and survival.

RESULTS

In 788 of 790 enrolled patients with prospectively recorded baseline BMI and metformin exposure status, lower BMI was not associated with survival, but was associated with high volume disease (p < 0.0001) and poorer baseline QOL on functional assessment of cancer therapy-prostate (p = 0.008). Only 68 patients had prevalent metformin exposure at baseline in the CHAARTED trial. Four groups were identified: ADT + D + metformin (n = 39); ADT + D (n = 357); ADT + metformin (n = 29); and ADT alone (n = 363). Baseline clinicopathologic characteristics were similar between groups. In this small exploratory multivariable analysis, metformin exposure was not associated with survival (hazard ratio: 1.15; 95% confidence interval: 0.81-1.63, p = 0.44).

CONCLUSIONS

There was no link between baseline BMI and survival, but lower baseline BMI was associated with features of greater cancer burden and poorer QOL.

Insight into the interplay between mitochondria-regulated cell death and energetic metabolism in osteosarcoma

Osteosarcoma (OS) is a pediatric malignant bone tumor that predominantly affects adolescent and young adults. It has high risk for relapse and over the last four decades no improvement of prognosis was achieved. It is therefore crucial to identify new drug candidates for OS treatment to combat drug resistance, limit relapse, and stop metastatic spread. Two acquired hallmarks of cancer cells, mitochondria-related regulated cell death (RCD) and metabolism are intimately connected. Both have been shown to be dysregulated in OS, making them attractive targets for novel treatment. Promising OS treatment strategies focus on promoting RCD by targeting key molecular actors in metabolic reprogramming. The exact interplay in OS, however, has not been systematically analyzed. We therefore review these aspects by synthesizing current knowledge in apoptosis, ferroptosis, necroptosis, pyroptosis, and autophagy in OS. Additionally, we outline an overview of mitochondrial function and metabolic profiles in different preclinical OS models. Finally, we discuss the mechanism of action of two novel molecule combinations currently investigated in active clinical trials: metformin and the combination of ADI-PEG20, Docetaxel and Gemcitabine.

Characterization of the SGLT2 Interaction Network and Its Regulation by SGLT2 Inhibitors: A Bioinformatic Analysis

Background: Sodium–glucose cotransporter 2 (SGLT2), also known as solute carrier family 5 member 2 (SLC5A2), is a promising target for a new class of drugs primarily established as kidney-targeting, effective glucose-lowering agents used in diabetes mellitus (DM) patients. Increasing evidence indicates that besides renal effects, SGLT2 inhibitors (SGLT2i) have also a systemic impact via indirectly targeting the heart and other tissues. Our hypothesis states that the pleiotropic effects of SGLT2i are associated with their binding force, location of targets in the SGLT2 networks, targets involvement in signaling pathways, and their tissue-specific expression.

Methods: Thus, to investigate differences in SGLT2i impact on human organisms, we re-created the SGLT2 interaction network incorporating its inhibitors and metformin and analyzed its tissue-specific expression using publicly available datasets. We analyzed it in the context of the so-called key terms ( autophagy, oxidative stress, aging, senescence, inflammation, AMPK pathways, and mTOR pathways) which seem to be crucial to elucidating the SGLT2 role in a variety of clinical manifestations.

Results: Analysis of SGLT2 and its network components’ expression confidence identified selected organs in the following order: kidney, liver, adipose tissue, blood, heart, muscle, intestine, brain, and artery according to the TISSUES database. Drug repurposing analysis of known SGLT2i pointed out the influence of SGLT1 regulators on the heart and intestine tissue. Additionally, dapagliflozin seems to also have a stronger impact on brain tissue through the regulation of SGLT3 and SLC5A11. The shortest path analysis identified interaction SIRT1-SGLT2 among the top five interactions across six from seven analyzed networks associated with the key terms. Other top first-level SGLT2 interactors associated with key terms were not only ADIPOQ, INS, GLUT4, ACE, and GLUT1 but also less recognized ILK and ADCY7. Among other interactors which appeared in multiple shortest-path analyses were GPT, COG2, and MGAM. Enrichment analysis of SGLT2 network components showed the highest overrepresentation of hypertensive disease, DM-related diseases for both levels of SGLT2 interactors. Additionally, for the extended SGLT2 network, we observed enrichment in obesity (including SGLT1), cancer-related terms, neuroactive ligand–receptor interaction, and neutrophil-mediated immunity.

Conclusion: This study provides comprehensive and ranked information about the SGLT2 interaction network in the context of tissue expression and can help to predict the clinical effects of the SGLT2i.

Prostate cancer-Exercise and Metformin Trial (Pre-EMpT): study protocol for a feasibility factorial randomized controlled trial in men with localised or locally advanced prostate cancer

Background

Evidence from observational studies have shown that moderate intensity physical activity can reduce risk of progression and cancer-specific mortality in participants with prostate cancer. Epidemiological studies have also shown participants taking metformin to have a reduced risk of prostate cancer. However, data from randomised controlled trials supporting the use of these interventions are limited. The Prostate cancer–Exercise and Metformin Trial examines that feasibility of randomising participants diagnosed with localised or locally advanced prostate cancer to interventions that modify physical activity and blood glucose levels. The primary outcomes are randomisation rates and adherence to the interventions over 6 months. The secondary outcomes include intervention tolerability and retention rates, measures of insulin-like growth factor I, prostate-specific antigen, physical activity, symptom-reporting, and quality of life.

Methods

Participants are randomised in a 2 × 2 factorial design to both a physical activity (brisk walking or control) and a pharmacological (metformin or control) intervention. Participants perform the interventions for 6 months with final measures collected at 12 months follow-up.

Discussion

Our trial will determine whether participants diagnosed with localised or locally advanced prostate cancer, who are scheduled for radical treatments or being monitored for signs of cancer progression, can be randomised to a 6 months physical activity and metformin intervention. The findings from our trial will inform a larger trial powered to examine the clinical benefits of these interventions.

Trial registration

Prostate Cancer Exercise and Metformin Trial (Pre-EMpT) is registered on the ISRCTN registry, reference number ISRCTN13543667. Date of registration 2nd August 2018–retrospectively registered. First participant was recruited on 11th September 2018.

Synergic Effect of Metformin and Everolimus on Mitochondrial Dynamics of Renal Cell Carcinoma

Renal cell carcinoma (RCC) frequently recurs or metastasizes after surgical resection. Everolimus, an mTOR inhibitor, is used as a second-line treatment, but the response of RCC to everolimus is insufficient. Metformin is an antidiabetic drug; recent reports have indicated its anti-cancer effects in various cancers, and it is known to have synergistic effects with other drugs. We investigated the possibility of coadministering everolimus and metformin as an effective treatment for RCC. RCC cells treated with a combination of the two drugs showed significantly inhibited cell viability, cell migration, and invasion, and increased apoptosis compared to those treated with each drug alone. An anti-cancer synergistic effect was also confirmed in the xenograft model. Transcriptome analysis for identifying the underlying mechanism of the combined treatment showed the downregulation of mitochondrial fusion genes and upregulation of mitochondrial fission genes by the combination treatment. Changes in mitochondrial dynamics following the combination treatment were observed using LysoTracker, LysoSensor, and JC-1 staining. In conclusion, the combination of everolimus and metformin inhibited RCC growth by disrupting mitochondrial dynamics. Therefore, we suggest that a treatment combining metformin and everolimus disrupts mitochondrial dynamics in RCC, and may be a novel strategy for RCC treatment.

Statin and metformin use and outcomes in patients with castration-resistant prostate cancer treated with enzalutamide: A meta-analysis of AFFIRM, PREVAIL and PROSPER

BACKGROUND

Statins and metformin are commonly prescribed for patients, including those with prostate cancer. Preclinical and epidemiologic studies of each agent have suggested anti-cancer properties.

METHODS

Patient data from three randomised, double-blind, placebo-controlled, phase III studies evaluating enzalutamide (AFFIRM, PREVAIL and PROSPER) in patients with castration-resistant prostate cancer were included in this analysis. This post hoc, retrospective study examined the association of statin and metformin on radiographic progression-free survival (rPFS), metastasis-free survival (MFS), toxicity and overall survival (OS). After adjusting for available clinical prognostic variables, multivariate analyses were performed on pooled data from AFFIRM and PREVAIL, all three trials pooled, and each trial individually, to assess differential efficacy in these end-points associated with the baseline use of these medications.

RESULTS

In the multivariate analysis of the individual trials, OS and rPFS/MFS were not significantly influenced by statin or metformin use in AFFIRM or PROSPER. However, in PREVAIL, OS was significantly influenced by statin (hazard ratio [HR] 0.72; 95% confidence interval [CI] 0.59-0.89) and rPFS was significantly influenced by metformin (HR, 0.48; 95% CI 0.34-0.70). In pooled analyses, improved OS was significantly associated with statin use but not metformin use for AFFIRM+PREVAIL trials (HR 0.83; 95% CI 0.72-0.96) and AFFIRM+PREVAIL+PROSPER (HR 0.75; 95% CI 0.66-0.85).

CONCLUSIONS

The association between statin or metformin use and rPFS, MFS and OS was inconsistent across three trials. Analyses of all three trials pooled and AFFIRM+PREVAIL pooled revealed that statin but not metformin use was significantly associated with a reduced risk of death in enzalutamide-treated patients. Additional prospective, controlled studies are warranted.

CLINICAL TRIAL REGISTRATION

AFFIRM (NCT00974311), PREVAIL (NCT01212991) and PROSPER (NCT02003924).

Metformin exerts an antitumor effect by inhibiting bladder cancer cell migration and growth, and promoting apoptosis through the PI3K/AKT/mTOR pathway

Background

To observe and explore the effect of metformin on the migration and proliferation of bladder cancer T24 and 5637 cells in vitro.

Methods

Bladder cancer T24 and 5637 cell lines were cultured in vitro, and were divided into group A (blank control group) and group B (metformin group: 5, 10, 15, and 20 mmol/L); both groups were plated on 6-well plates at the same time. Culture in 24-well plates was used for wound healing assays and in 96-well plates for Transwell migration and invasion, and Cell Counting Kit-8 proliferation experiments. We observed and detected the cell migration and proliferation ability of each group at 48 h, and calculated the cell migration area and survival rate. Flow cytometry was used to detect cell apoptosis in the groups. The apoptosis-related proteins, cleaved-caspase 3, cleaved-PARP, and the PI3K/AKT/mTOR signaling pathway member proteins PI3K, phosphorylated (p)-PI3K, AKT, p-AKT, mTOR, and p-mTOR were detected using western blotting.

Results

After 48 h of treatment with different concentrations of metformin, the cell migration and proliferation capabilities were significantly lower than those in the blank control group. The proliferation and migration abilities of T24 and 5637 cells decreased in a metformin concentration-dependent manner (P < 0.05). The apoptosis rate under different concentrations of metformin, as detected by flow cytometry, showed a significantly higher rate in the metformin group than in the control group (P < 0.05). Compared with that in the control group, the level of cleaved-caspase 3 and cleaved-PARP protein in the metformin group was increased in each treatment group, and the levels of p-mTOR, p-AKT, and p-PI3K decreased significantly compared with those in the control group (P < 0.05).

Conclusion

Metformin inhibited bladder cancer T24 and 5637 cell migration and proliferation, and induced their apoptosis. The mechanism might involve inhibition of the activation of the PI3K/AKT/mTOR signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01027-2.

Metformin suppresses lung adenocarcinoma by downregulating long non-coding RNA (lncRNA) AFAP1-AS1 and secreted phosphoprotein 1 (SPP1) while upregulating miR-3163

AFAP1-AS1 plays a pro-tumor role in lung cancer. However, no investigation has focused on whether it is involved in the anticancer activity of metformin (Met) in the treatment of lung adenocarcinoma (LUAD). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed to detect the expression of long non-coding (lnc)RNA AFAP1-AS1, the microRNA (miR)-3163, and secreted phosphoprotein 1 (SPP1) in LUAD tissues, or of A549 and H3122 cells. Cell Counting Kit-8, wound scratch, and cell invasion assays were performed to evaluate the effect of the overexpression of lncRNA AFAP1-AS1, miR-3163, and SPP1 on the malignant behaviors of A549 and H3122 cells. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway-related proteins were detected by Western blot analysis. Dual luciferase reporter or RIP assays were used to determine the interplay between AFAP1-AS1 and miR-3163, or of miR-3163 and SPP1. Met inhibits the malignant characteristics of A549 and H3122 cells in vitro. GEPIA database analysis showed that AFAP1-AS1 is a highly expressed lncRNA in LUAD tissues, which was validated by RT-qPCR. Overexpression of AFAP1-AS1 suppressed the met-mediated anti-tumor activity in A549 and H3122 cells, while AFAP1-AS1 silencing promoted it. Met inhibited AFAP1-AS1 expression, which resulted in reduced proliferation, migration, and invasion in A549 and H3122 cells. This led to AFAP1-AS1-mediated suppression of miR-3163 and, subsequently, the upregulation of SPP1. Met exerts its antitumor activities by regulating the AFAP1-AS1/miR-3163/SPP1/PI3K/Akt/mTOR axis. Our findings deepen our understanding of mechanisms underlying anti-tumor effect of Met in LUAD.

Exploiting the Metabolic Consequences of PTEN Loss and Akt/Hexokinase 2 Hyperactivation in Prostate Cancer: A New Role for δ-Tocotrienol

The Warburg effect is commonly recognized as a hallmark of nearly all tumors. In prostate cancer (PCa), it has been shown to be driven by PTEN loss- and Akt hyperactivation-associated upregulation of hexokinase 2 (HK2). δ-Tocotrienol (δ-TT) is an extensively studied antitumor compound; however, its role in affecting PCa glycolysis is still unclear. Herein, we demonstrated that δ-TT inhibits glucose uptake and lactate production in PTEN-deficient LNCaP and PC3 PCa cells, by specifically decreasing HK2 expression. Notably, this was accompanied by the inhibition of the Akt pathway. Moreover, the nutraceutical could synergize with the well-known hypoglycemic agent metformin in inducing PCa cell death, highlighting the crucial role of the above metabolic phenotype in δ-TT-mediated cytotoxicity. Collectively, these results unravel novel inhibitory effects of δ-TT on glycolytic reprogramming in PCa, thus providing new perspectives into the mechanisms of its antitumor activity and into its use in combination therapy.

Exploring the Impact of the Obesity Paradox on Lung Cancer and Other Malignancies

Simple Summary

Studies have shown that obesity is associated with many adverse health effects, including worse cancer outcomes. Many studies paradoxically suggest a survival benefit for obesity in treatment outcomes of cancers such as non-small-cell lung cancer. This relationship is not seen in animal models. We hypothesize that this relationship is secondary to suboptimal quantification of adiposity, enhanced immunotherapy response, and variables such as sex, medications, and smoking status. There are many ways to measure and classify adiposity, but the ability to distinguish abdominal obesity is likely key in predicting accurate prognosis. There are many ways obesity impacts cancer treatment course from diagnosis to survivorship. In this paper, we aim to analyze the factors contributing to the obesity paradox and its effect on lung cancer. This can aid the treatment and prognosis of lung cancer and may support further research into obesity-specific impacts on this malignancy.

Abstract

There is a paradoxical relationship between obesity, as measured by BMI, and many types of cancer, including non-small-cell lung cancer. Obese non-small-cell lung cancer patients have been shown to fare better than their non-obese counterparts. To analyze the multifaceted effects of obesity on oncologic outcomes, we reviewed the literature on the obesity paradox, methods to measure adiposity, the obesity-related derangements in immunology and metabolism, and the oncologic impact of confounding variables such as gender, smoking, and concomitant medications such as statins and metformin. We analyzed how these aspects may contribute to the obesity paradox and cancer outcomes with a focus on lung cancer. We concluded that the use of BMI to measure adiposity is limited and should be replaced by a method that can differentiate abdominal obesity. We also concluded that the concomitant metabolic and immunologic derangements caused by obesity contribute to the obesity paradox. Medications, gender, and smoking are additional variables that impact oncologic outcomes, and further research needs to be performed to solidify the mechanisms.

Overcoming Drug Resistance in Advanced Prostate Cancer by Drug Repurposing

Prostate cancer (PCa) is the second most common cancer in men. Common treatments include active surveillance, surgery, or radiation. Androgen deprivation therapy and chemotherapy are usually reserved for advanced disease or biochemical recurrence, such as castration-resistant prostate cancer (CRPC), but they are not considered curative because PCa cells eventually develop drug resistance. The latter is achieved through various cellular mechanisms that ultimately circumvent the pharmaceutical’s mode of action. The need for novel therapeutic approaches is necessary under these circumstances. An alternative way to treat PCa is by repurposing of existing drugs that were initially intended for other conditions. By extrapolating the effects of previously approved drugs to the intracellular processes of PCa, treatment options will expand. In addition, drug repurposing is cost-effective and efficient because it utilizes drugs that have already demonstrated safety and efficacy. This review catalogues the drugs that can be repurposed for PCa in preclinical studies as well as clinical trials.

Frontiers in Anti-Cancer Drug Discovery: Challenges and Perspectives of Metformin as Anti-Angiogenic Add-On Therapy in Glioblastoma

Simple Summary

Glioblastoma is the most aggressive primary brain tumor, with the highest incidence and the worst prognosis. Life expectancy from diagnosis remains dismal, at around 15 months, despite surgical resection and treatment with radiotherapy and chemotherapy. Given the aggressiveness of the tumor and the inefficiency of the treatments adopted to date, the scientific research investigates innovative therapeutic approaches. Importantly, angiogenesis represents one of the main features of glioblastoma, becoming in the last few years a major candidate for target therapy. Metformin, a well-established therapy for type 2 diabetes, offered excellent results in preventing and fighting tumor progression, particularly against angiogenic mechanisms. Therefore, the purpose of this review is to summarize and discuss experimental evidence of metformin anti-cancer efficacy, with the aim of proposing this totally safe and tolerable drug as add-on therapy against glioblastoma.

Abstract

Glioblastoma is the most common primitive tumor in adult central nervous system (CNS), classified as grade IV according to WHO 2016 classification. Glioblastoma shows a poor prognosis with an average survival of approximately 15 months, representing an extreme therapeutic challenge. One of its distinctive and aggressive features is aberrant angiogenesis, which drives tumor neovascularization, representing a promising candidate for molecular target therapy. Although several pre-clinical studies and clinical trials have shown promising results, anti-angiogenic drugs have not led to a significant improvement in overall survival (OS), suggesting the necessity of identifying novel therapeutic strategies. Metformin, an anti-hyperglycemic drug of the Biguanides family, used as first line treatment in Type 2 Diabetes Mellitus (T2DM), has demonstrated in vitro and in vivo antitumoral efficacy in many different tumors, including glioblastoma. From this evidence, a process of repurposing of the drug has begun, leading to the demonstration of inhibition of various oncopromoter mechanisms and, consequently, to the identification of the molecular pathways involved. Here, we review and discuss metformin’s potential antitumoral effects on glioblastoma, inspecting if it could properly act as an anti-angiogenic compound to be considered as a safely add-on therapy in the treatment and management of glioblastoma patients.

Prostate Cancer-specific Survival After Radical Prostatectomy Is Improved Among Metformin Users but Not Among Other Antidiabetic Drug Users

Background

Metformin has been linked to improved survival among diabetic prostate cancer (PCa) patients, while hyperinsulinemia and insulin usage has been related to worse prognosis.

Objective

To evaluate the association of metformin and other antidiabetic drugs with PCa death and androgen deprivation therapy (ADT).

Design, setting, and participants

The study cohort included 14 424 men who underwent radical prostatectomy in Finland during 1995–2013. Cases were identified, and clinical data were collected from patient files and national registries using personal identification numbers.

Intervention

Information on the use of each antidiabetic drug during 1995–2014 was collected from prescription registry of the Social Insurance Institution of Finland.

Outcome measurements and statistical analysis

The risks of PCa death and initiation of ADT were analyzed by antidiabetic drug use with the Cox regression method. Each antidiabetic drug group was analyzed separately to model simultaneous usage. Pre- and postdiagnostic uses were analyzed separately.

Results and limitations

Prediagnostic use of antidiabetic drugs in general had no association with the risk of PCa death. Prediagnostic use of metformin was related to a reduced risk of ADT initiation (hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.59–0.96), while high-dose insulin users had an increased risk. Overall, antidiabetic drug use after PCa diagnosis was associated with an elevated risk of PCa death. Only postdiagnostic metformin use was associated with reduced risks of PCa death (HR 0.47, 95% CI 0.30–0.76) and ADT initiation compared with nonusers. Study limitations are missing information on glycemic control, smoking, living or exercise habits, prostate-specific antigen, and Gleason score.

Conclusions

Among surgically treated PCa patients, use of metformin was associated with improved disease-specific survival, while insulin and insulin secretagogues were associated with poor survival. Metformin might be a favorable diabetes treatment among men with PCa.

Patient summary

In this Finnish nationwide study, we found that the risks of prostate cancer death and cancer progression are lowered among metformin users, but not among other antidiabetic drug users. Metformin might be a favorable treatment choice for diabetes in men with prostate cancer.

Could Reducing Body Fatness Reduce the Risk of Aggressive Prostate Cancer via the Insulin Signalling Pathway? A Systematic Review of the Mechanistic Pathway

Excess body weight is thought to increase the risk of aggressive prostate cancer (PCa), although the biological mechanism is currently unclear. Body fatness is positively associated with a diminished cellular response to insulin and biomarkers of insulin signalling have been positively associated with PCa risk. We carried out a two-pronged systematic review of (a) the effect of reducing body fatness on insulin biomarker levels and (b) the effect of insulin biomarkers on PCa risk, to determine whether a reduction in body fatness could reduce PCa risk via effects on the insulin signalling pathway. We identified seven eligible randomised controlled trials of interventions designed to reduce body fatness which measured insulin biomarkers as an outcome, and six eligible prospective observational studies of insulin biomarkers and PCa risk. We found some evidence that a reduction in body fatness improved insulin sensitivity although our confidence in this evidence was low based on GRADE (Grading of Recommendations, Assessment, Development and Evaluations). We were unable to reach any conclusions on the effect of insulin sensitivity on PCa risk from the few studies included in our systematic review. A reduction in body fatness may reduce PCa risk via insulin signalling, but more high-quality evidence is needed before any conclusions can be reached regarding PCa.

Itraconazole improves survival outcomes in patients with colon cancer by inducing autophagic cell death and inhibiting transketolase expression

The incidence of colon cancer continues to increase annually, and it is the leading cause of cancer-associated mortality worldwide. Altering cell metabolism and inducing autophagic cell death have recently emerged as novel strategies in preventing tumor growth. Autophagy plays an essential role in energy production by degrading damaged cellular components and is also associated with tumor proliferation suppression. Itraconazole is an FDA-approved drug used as an antifungal medication and has been reported to induce autophagic cell death in breast cancer. However, the effects of itraconazole on cell metabolism and induction of apoptosis in colon cancer remain unclear. The present study analyzed extensive data from patients diagnosed with colon cancer using itraconazole between January 2011 and December 2015, from the Taiwanese National Health Insurance Research Database. The underlying molecular mechanisms of itraconazole in autophagy-induced cell death were also investigated. The results demonstrated that the 5-year survival rate was significantly higher in patients with colon cancer who received itraconazole treatment. In addition, itraconazole decreased the viability and cell colony formation, and induced cleaved caspase-3 expression and G₁ cell cycle arrest of COLO 205 and HCT 116 cells. Notably, itraconazole induced autophagy by enhancing LC3B and p62 expression. Following LC3 knockdown, the viability of itraconazole-treated COLO 205 and HCT 116 cells notably improved. Taken together, the results of the present study suggest that itraconazole may have a beneficial effect on patients with colon cancer, and its underlying molecular mechanisms may be associated with the induction of autophagic cell death.

TAXOMET: A French Prospective Multicentric Randomized Phase II Study of Docetaxel Plus Metformin Versus Docetaxel Plus Placebo in Metastatic Castration-Resistant Prostate Cancer

BACKGROUND

Docetaxel (DOCE) is a standard of care in metastatic castration-resistant prostate cancer (mCRPC). Several retrospective studies suggested a decrease in Prostate Cancer incidence and mortality with metformin (MET). MET has also demonstrated anti-tumor activity in Prostate Cancer preclinical models, with increased apoptosis when added to DOCE. We aimed at exploring the role of MET in combination with DOCE in mCRPC.

PATIENTS AND METHODS

Non-diabetic mCRPC patients were randomly assigned to receive DOCE 75 mg/m² every 21 days + prednisone (5 mg. BID) with either MET 850 mg BID (D+M) or placebo (D+P) up to 10 cycles. Prostate-Specific Antigen (PSA) response ≥50% from baseline was the primary end point. Secondary end points included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), toxicity and quality of life (QoL).

RESULTS

Out of 99 patients were randomized (D+M = 50; D+P = 49) in 10 French centers. The median follow-up was 86 (IQR 73-88) months. The PSA-response rate reached 66% in the D+M arm, but was not different from that observed in the D+P arm (63%, P = 0,94). In the D+M and D+P arms, the ORR was 28% and 24%, the median PFS was 7.8 and 6.0 months and the median OS was 27 and 20 months (ns), respectively. Diarrhea grade I to II was more frequent in the MET arm (66% vs. 43%). No impairment of QoL was observed.

CONCLUSION

MET addition failed to improve the standard DOCE regimen in mCRPC. Further research targeting tumor cell metabolism should be performed.

The role of AMPK/mTOR signaling pathway in anticancer activity of metformin

Metformin (MTF) is a widely used drug for the treatment of diabetes mellitus type 2 (DM2) and frequently used as an adjuvant therapy for polycystic ovarian syndrome, metabolic syndrome, and in some cases also tuberculosis. Its protective effect on the cardiovascular system has also been described. Recently, MTF was subjected to various analyzes and studies that showed its beneficial effects in cancer treatment such as reducing cancer cell proliferation, reducing tumor growth, inducing apoptosis, reducing cancer risk in diabetic patients, or reducing likelihood of relapse. One of the MTF's mechanisms of action is the activation of adenosine-monophosphate-activated protein kinase (AMPK). Several studies have shown that AMPK/mammalian target of rapamycin (mTOR) pathway has anticancer effect in vivo and in vitro. The aim of this review is to present the anticancer activity of MTF highlighting the importance of the AMPK/mTOR pathway in the cancer process.

Metformin mitigates PLCε gene expression and modulates the Notch1/Hes and androgen receptor signaling pathways in castration-resistant prostate cancer xenograft models

The present study aimed to establish a mouse model of patient-derived castration-resistant prostate cancer (CRPC) xenograft tumors, and to evaluate the effects of various doses of metformin on phospholipase Cε (PLCε) expression and the neurogenic locus notch homolog protein 1 (Notch1)/hairy and enhancer of split 1 and androgen receptor (AR) signaling pathways via western blotting and reverse transcription-quantitative PCR. Additionally, phorbol 12-myristate 13-acetate was used to activate PLC, and Jagged1 was used as a Notch activator to verify whether metformin could suppress CRPC development via the PLCε/Notch1/AR pathways. The results confirmed that metformin may serve critical roles in CRPC by significantly inhibiting the occurrence, growth and proliferation of CRPC tumors by decreasing PLCε/Notch1 expression and AR nucleation.

Histological and biochemical investigation of the renoprotective effects of metformin in diabetic and prostate cancer model

BACKGROUND

Diabetes and cancer have common physiological and biochemical mechanisms. Metformin is the preferred drug of choice for the treatment of diabetes. Prostate cancer can be modeled in by injection of MAT-Lylu cells. A model of diabetes in rats is induced by streptozotocin injectıon. In the current study, we explored the mechanisms by which diabetes accelerates cancer, and evaluated the effects of metformin to know whether it has any impact against the damage caused by cancer and diabetic + cancer via histopathological and biochemical parameters of kidney tissue.

METHODS

The experiment was carried out in rats. Groups 1-Control, 2- Diabetic, 3-Cancer, 4-Diabetic + cancer, 5-Diabetic + cancer + metformin, 6-Cancer + metformin. Metformin treatment was applied by gavage every day. The research ended on the 14th day. The collected kidney tissue sections were stained with Hematoxylin-Eosin.

RESULTS

Histological evaluation showed moderate to severe damage to the kidney tissue following diabetic and cancer processess. In diabetic, cancer and diabetic + cancer groups, reduced glutathione levels, total antioxidant status, sodium/potassium-ATPase and paraoxonase1 activities were found to be significantly abated. While advanced oxidized protein products, lipid peroxidation, nitric oxide, tumor necrosis factor-alpha, reactive oxygen species levels, total oxidant status, catalase, superoxide dismutase, glutathione-related antioxidant enzymes, myeloperoxidase, and arginase activities were significantly raised. The administration of metformin reversed these defects. The outcome of the reveals that histopathological and biochemical damage in cancer and diabetes + cancer groups decreased in the groups that received metformin.

CONCLUSION

In conclusion, metformin treatment can be considered an adjuvant candidate for kidney tissue in diabetes, prostate cancer and cancer therapy related damage.

Drug Repositioning for the Treatment of Hematologic Disease: Limits, Challenges and Future Perspectives

Drug repositioning is a strategy to identify new uses for approved or investigational drugs that are used off-label outside the scope of the original medical indication. In this review, we report the most relevant studies about drug repositioning in hematology, reporting the signalling pathways and molecular targets of these drugs, and describing the biological mechanisms which are responsible for their anticancer effects. Although the majority of studies on drug repositioning in hematology concern acute myeloid leukemia and multiple myeloma, numerous studies are present in the literature on the possibility of using these drugs also in other hematological diseases, such as acute lymphoblastic leukemia, chronic myeloid leukemia, and lymphomas. Numerous anti-infectious drugs and chemical entities used for the therapy of neurological or endocrine diseases, oral antidiabetics, statins and medications used to treat high blood pressure and heart failure, bisphosphonate and natural substance such as artemisin and curcumin, have found a place in the treatment of hematological diseases. Moreover, several molecules drastically reversed the resistance of the tumor cells to the chemotherapeutic drugs both in vitro and in vivo.

Exploring the effect of Gupi Xiaoji Prescription on hepatitis B virus-related liver cancer through network pharmacology and in vitro experiments

AIM AND OBJECTIVE

To study the effect of Gupi Xiaoji Prescription (GXP) on hepatitis B virus(HBV)-related liver cancer through network pharmacology coupled with in vitro experiments and explore their related mechanisms.

MATERIALS AND METHODS

Gupi Xiaoji Prescription's chemical constituents and the action targets of its six medicinal components were identified using several databases. These included the Traditional Chinese Medicine Systems Pharmacology Database （TCMSP), the Bioinformatics Analysis Tool for Molecular mechANism of TCM (BATMAN-TCM), and the Traditional Chinese Medicine Integrated Database (TCMID), while GeneCards and OMIM were used to compile relevant liver cancer disease targets. Pathway enrichment of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), analysis of potential targets, and analysis of the enriched pathways in literature were executed in R. The Hepatocellular carcinoma (HCC)-derived HepG2.2.15 cell line stably expresses and replicates HBV. In vitro experiments with HepG2.2.15 were used to verify GXP's effects on HBV-related liver cancer, while the human liver cancer cell line HepG2 was used as the control.

RESULTS

171 active ingredients and 259 potential drug targets were screened from GXP, involving 181 pathways in vitro. These assays identified Polyphyllin I as an effective GXP component. Notably, GXP inhibited cell proliferation and metastasis in a concentration-dependent manner (P < 0.01). In comparison with the vehicle group, the fluorescence intensity of each drug group was significantly weakened (P < 0.01), while the drug group Mitofusins 1(MFN1) and protein expression level of Mitofusins 2 (MFN2) increased significantly. The protein expression level of Mitochondrial fission protein 1 (FIS1) and Optic Atrophy 1 (OPA1) also showed significant decreases (P < 0.01). Molecular docking revealed Fructus saponins I's high affinity with FIS1, MFN1, MFN2, and OPA1.

CONCLUSION

The network pharmacology results indicate that Gupi Xiaoji Prescription may treat liver cancer by regulating mitochondrial division and fusion of key genes to disrupt liver cancer cells' energy metabolism. In vitro experiments also verified that GXP could inhibit the proliferation and migration of HepG2.2.15 cells by up-regulating MFN1 and MFN2, down-regulating the expression of FIS1 and OPA1 in addition to damaging mitochondria. Consistent with network pharmacology and molecular docking results, Polyphyllin I may be the most active compound of the formula's components. It also shows that Traditional Chinese medicine (TCM) plays a significant, targeted role in the treatment of HBV-related liver cancer.

The Influence of Anti-Diabetic Drugs on Prostate Cancer

The incidences of prostate cancer (PC) and diabetes are increasing, with a sustained trend. The occurrence of PC and type 2 diabetes mellitus (T2DM) is growing with aging. The correlation between PC occurrence and diabetes is noteworthy, as T2DM is correlated with a reduced risk of incidence of prostate cancer. Despite this reduction, diabetes mellitus increases the mortality in many cancer types, including prostate cancer. The treatment of T2DM is based on lifestyle changes and pharmacological management. Current available drugs, except insulin, are aimed at increasing insulin secretion (sulfonylureas, incretin drugs), improving insulin sensitivity (biguanides, thiazolidinediones), or increasing urinary glucose excretion (gliflozin). Comorbidities should be taken into consideration during the treatment of T2DM. This review describes currently known information about the mechanism and impact of commonly used antidiabetic drugs on the incidence and progression of PC. Outcomes of pre-clinical studies are briefly presented and their correlations with available clinical trials have also been observed. Available reports and meta-analyses demonstrate that most anti-diabetic drugs do not increase the risk during the treatment of patients with PC. However, some reports show a potential advantage of treatment of T2DM with specific drugs. Based on clinical reports, use of metformin should be considered as a therapeutic option. Moreover, anticancer properties of metformin were augmented while combined with GLP-1 analogs.

Endocrinology of the Aging Prostate: Current Concepts

Benign prostate hyperplasia (BPH), one of the most common diseases in older men, adversely affects quality-of-life due to the presence of low urinary tract symptoms (LUTS). Numerous data support the presence of an association between BPH-related LUTS (BPH-LUTS) and metabolic syndrome (MetS). Whether hormonal changes occurring in MetS play a role in the pathogenesis of BPH-LUTS is a debated issue. Therefore, this article aimed to systematically review the impact of hormonal changes that occur during aging on the prostate, including the role of sex hormones, insulin-like growth factor 1, thyroid hormones, and insulin. The possible explanatory mechanisms of the association between BPH-LUTS and MetS are also discussed. In particular, the presence of a male polycystic ovarian syndrome (PCOS)-equivalent may represent a possible hypothesis to support this link. Male PCOS-equivalent has been defined as an endocrine syndrome with a metabolic background, which predisposes to the development of type II diabetes mellitus, cardiovascular diseases, prostate cancer, BPH and prostatitis in old age. Its early identification would help prevent the onset of these long-term complications.

Current Status and Application of Metformin for Prostate Cancer: A Comprehensive Review

Metformin, an oral biguanide used for first-line treatment of type 2 diabetes mellitus, has attracted attention for its anti-proliferative and anti-cancer effects in several solid tumors, including prostate cancer (PCa). Liver kinase B1 (LKB1) and adenosine monophosphate-activated protein kinase (AMPK) activation, inhibition of the mammalian target of rapamycin (mTOR) activity and protein synthesis, induction of apoptosis and autophagy by p53 and p21, and decreased blood insulin level have been suggested as direct anti-cancer mechanisms of metformin. Research has shown that PCa development and progression are associated with metabolic syndrome and its components. Therefore, reduction in the risk of PCa and improvement in survival in metformin users may be the results of the direct anti-cancer mechanisms of the drug or the secondary effects from improvement of metabolic syndrome. In contrast, some research has suggested that there is no association between metformin use and PCa incidence or survival. In this comprehensive review, we summarize updated evidence on the relationship between metformin use and oncological effects in patients with PCa. We also highlight ongoing clinical trials evaluating metformin as an adjuvant therapy in novel drug combinations in various disease settings.

Androgen Receptor Signaling and Metabolic and Cellular Plasticity During Progression to Castration Resistant Prostate Cancer

Metabolic reprogramming is associated with re/activation and antagonism of androgen receptor (AR) signaling that drives prostate cancer (PCa) progression to castration resistance, respectively. In particular, AR signaling influences the fates of citrate that uniquely characterizes normal and malignant prostatic metabolism (i.e., mitochondrial export and extracellular secretion in normal prostate, mitochondrial retention and oxidation to support oxidative phenotype of primary PCa, and extra-mitochondrial interconversion into acetyl-CoA for fatty acid synthesis and epigenetics in the advanced PCa). The emergence of castration-resistant PCa (CRPC) involves reactivation of AR signaling, which is then further targeted by androgen synthesis inhibitors (abiraterone) and AR-ligand inhibitors (enzalutamide, apalutamide, and daroglutamide). However, based on AR dependency, two distinct metabolic and cellular adaptations contribute to development of resistance to these agents and progression to aggressive and lethal disease, with the tumor ultimately becoming highly glycolytic and with imaging by a tracer of tumor energetics, ¹⁸F-fluorodoxyglucose (¹⁸F-FDG). Another major resistance mechanism involves a lineage alteration into AR-indifferent carcinoma such a neuroendocrine which is diagnostically characterized by robust ¹⁸F-FDG uptake and loss of AR signaling. PCa is also characterized by metabolic alterations such as fatty acid and polyamine metabolism depending on AR signaling. In some cases, AR targeting induces rather than suppresses these alterations in cellular metabolism and energetics, which can be explored as therapeutic targets in lethal CRPC.

Impact of Concomitant Medications on Biochemical Outcome in Localised Prostate Cancer Treated with Radiotherapy and Androgen Deprivation Therapy

AIMS

Several classes of concomitant medications have been shown to affect oncological outcomes in patients with prostate cancer (PCa). We assessed the association between the use of commonly prescribed concomitant medications and biochemical relapse-free survival (bRFS) in patients with localised PCa treated with radiotherapy and androgen deprivation therapy (ADT).

MATERIALS AND METHODS

A secondary pooled analysis of two phase III randomised trials was carried out. In the first trial, patients with localised PCa with clinical stage T1b-T3, prostate-specific antigen <30 ng/ml and Gleason score ≤7 were treated with radical radiotherapy and 6 months of ADT starting 4 months before or concomitantly with radiotherapy. In the second trial, patients with high-risk PCa were treated with radical radiotherapy and 36 months of ADT with randomisation to three-dimensional conformal or intensity-modulated radiotherapy. Information on concomitant medications was collected from the medical record. Univariable and multivariable Cox regression was used to identify factors associated with bRFS.

RESULTS

Overall, 486 patients were evaluable. The median follow-up was 125 months; 10-year bRFS was 83.7%. On univariable analysis, receipt of metformin was significantly associated with worse bRFS. Ten-year bRFS was 73% and 85% for patients with and without concomitant metformin (adjusted hazard ratio 2.11, 95% confidence interval 1.03-4.33). Similar evidence of an association was observed with sulfonamide-based α1-receptor blockers (adjusted hazard ratio 2.72, 95% confidence interval 1.31-5.66). However, no such association was seen with receipt of quinazoline-based α1-receptor blockers (adjusted hazard ratio 1.09, 95% confidence interval 0.42-2.82). There was no significant association between bRFS and receipt of all other medication classes considered.

CONCLUSIONS

In this population of patients with localised PCa treated with radiotherapy and ADT, receipt of concomitant metformin and sulfonamide-based α1-receptor blockers was associated with inferior biochemical outcome. Randomised trials are required to assess the true effect of these medications on oncological outcomes in localised PCa.

The suggested chemopreventive association of metformin with prostate cancer in diabetic patients

PURPOSE

Metformin, an insulin sensitizer, is the most common first-line antidiabetic therapy. There is increasing evidence suggesting metformin can prevent the emergence of prostate cancer (CaP). We aimed to analyze the chemopreventive role of metformin, in conjunction with other putative chemopreventive medications (statins, proton-pump-inhibitors, alpha-blockers, 5-alpha-reductase inhibitors, diabetic medications) in a population-based cohort study.

METHODS

Data were incorporated from the Institute for Clinical and Evaluative Sciences to identify all diabetic men aged 66 and above with prior history of a negative prostate biopsy (PB) between 1994 and 2016, who were not on any of the medications prior to study inclusion. Multivariable Cox regression models with time-dependent covariates were used to assess the association of metformin to CaP diagnosis, subsequent PB, and use of androgen deprivation therapy (ADT). All models were adjusted for age, rurality, comorbidity, and year of study inclusion.

RESULTS

Overall, 2,332 diabetic men were included, with a median follow-up time of 9.4 years (interquartile range 5.4-13.4 years). A total of 2,036 patients (87.3%) received metformin. Compared to non-metformin users, metformin use was associated with decreased CaP diagnosis rate (HR 0.69, 95%CI 0.54-0.88, P = 0.003), lower hazard of undergoing an additional PB (HR 0.64, 95%CI 0.44-0.95, P = 0.03), and receiving ADT (HR 0.72, 95%CI 0.54-0.96, P = 0.003).

CONCLUSION

Men receiving metformin were less likely to have suspected or diagnosed CaP, and in those with CaP, the use of ADT was less common. Ongoing prospective randomized studies will determine if these findings correspond to the suggested associations of metformin in the emergence and/or progression of CaP.

Metformin suppresses Nrf2-mediated chemoresistance in hepatocellular carcinoma cells by increasing glycolysis

The diabetes drug metformin has recently been shown to possess anti-cancer properties when used with other chemotherapeutic drugs. However, detailed mechanisms by which metformin improves cancer treatment are poorly understood. Here we provide evidence in HepG2 hepatocellular carcinoma cells that metformin sensitizes cisplatin-resistant HepG2 cells (HepG2/DDP) through increasing cellular glycolysis and suppressing Nrf2-dependent transcription. We show that metformin increases glucose uptake and enhances glucose metabolism through glycolytic pathway, resulting in elevated concentrations of intracellular NADPH and lactate. Consistently, high glucose medium suppresses Nrf2-dependent transcription and sensitizes HepG2/DDP cells to cisplatin. Elevated glycolysis was required for metformin to regulate Nrf2-dependent transcription and cisplatin sensitivity, as inhibition of glycolysis with 2-Deoxy-D-glucose (2-DG) significantly mitigates the beneficial effect of metformin. Together, our study has revealed an important biological process and gene transcriptional program underlying the beneficial effect of metformin on reducing chemo-resistance in HepG2 cells and provided new information on improving chemotherapy of liver cancers.

Application of Anti-Inflammatory Agents in Prostate Cancer

Chronic inflammation is a major cause of human cancers. The environmental factors, such as microbiome, dietary components, and obesity, provoke chronic inflammation in the prostate, which promotes cancer development and progression. Crosstalk between immune cells and cancer cells enhances the secretion of intercellular signaling molecules, such as cytokines and chemokines, thereby orchestrating the generation of inflammatory microenvironment. Tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) play pivotal roles in inflammation-associated cancer by inhibiting effective anti-tumor immunity. Anti-inflammatory agents, such as aspirin, metformin, and statins, have potential application in chemoprevention of prostate cancer. Furthermore, pro-inflammatory immunity-targeted therapies may provide novel strategies to treat patients with cancer. Thus, anti-inflammatory agents are expected to suppress the “vicious cycle” created by immune and cancer cells and inhibit cancer progression. This review has explored the immune cells that facilitate prostate cancer development and progression, with particular focus on the application of anti-inflammatory agents for both chemoprevention and therapeutic approach in prostate cancer.

Metformin inhibits the activation of melanocortin receptors 2 and 3 in vitro: A possible mechanism for its anti-androgenic and weight balancing effects in vivo?

Metformin is recommended as one of the first-line drugs for the treatment of type 2 diabetes and the metabolic syndrome. In addition to its insulin sensitizing effects, it has been shown to attenuate androgen excess in women with polycystic ovary syndrome (PCOS) or congenital adrenal hyperplasia (CAH), as well as to ameliorate obesity. The mechanisms of metformin action seem manifold. Preclinical studies suggest that it inhibits the cellular stress response at the level of the mitochondrial OXPHOS system and through AMPK dependent and independent mechanisms. Recent studies have shown that metformin decreases ACTH secretion from pituitary and reduces ACTH-stimulated adrenal secretion. In this study we investigated its specific effect through the melanocortin receptor 2 (MC2R) on signaling targeting adrenal steroidogenesis. To assess this effect, we used mouse adrenal OS3 cells, which do not express the MC2R. Cells were transfected with the MC2R and stimulated by ACTH. Downstream cyclic AMP production was then assessed by a co-transfected cAMP-responsive vector producing luciferase that was measured by a dual luciferase assay. The amount of luciferase produced in this assay corresponds to the amount of receptor activation with varying amount of ACTH. The effect of metformin was then tested in this system. We found a significant inhibition of ACTH induced MC2R activation and signaling with 10 mM metformin. The ACTH concentration response curve (CRC) was half-log shifted and a ∼30 % reduction in maximum receptor response (Rmax) to ACTH in presence of metformin was observed. This effect was dose dependent with an IC₅₀ of 4.2 mM. qRT-PCR analyses showed that metformin decreased ACTH induced MC2R expression. Metformin did not affect cell viability and basal cAMP levels. We also tested the effect of metformin on homologous melanocortin receptors (MCRs). No significant effect was found on MC1R and MC4R activity. However, a log shift of EC₅₀ of ACTH stimulation on MC3R was observed with metformin treatment. Metformin also inhibited melanocortin stimulating hormone (αMSH) induced MC3R activity. In conclusion, we show that metformin acts on MC2R and MC3R signaling directly. The role of MC2R for steroidogenesis is well established. MC3R is involved in energy balance and seems to act as a rheostat when the metabolism is challenged. Our study may explain how metformin helps in weight loss and attenuates the excess response to ACTH in androgen excess disorders such as PCOS and CAH.

Tumour metabolism and its unique properties in prostate adenocarcinoma

Anabolic metabolism mediated by aberrant growth factor signalling fuels tumour growth and progression. The first biochemical descriptions of the altered metabolic nature of solid tumours were reported by Otto Warburg almost a century ago. Now, the study of tumour metabolism is being redefined by the development of new molecular tools, tumour modelling systems and precise instrumentation together with important advances in genetics, cell biology and spectroscopy. In contrast to Warburg's original hypothesis, accumulating evidence demonstrates a critical role for mitochondrial metabolism and substantial variation in the way in which different tumours metabolize nutrients to generate biomass. Furthermore, computational and experimental approaches suggest a dominant influence of the tissue-of-origin in shaping the metabolic reprogramming that enables tumour growth. For example, the unique metabolic properties of prostate adenocarcinoma are likely to stem from the distinct metabolism of the prostatic epithelium from which it emerges. Normal prostatic epithelium employs comparatively glycolytic metabolism to sustain physiological citrate secretion, whereas prostate adenocarcinoma consumes citrate to power oxidative phosphorylation and fuel lipogenesis, enabling tumour progression through metabolic reprogramming. Current data suggest that the distinct metabolic aberrations in prostate adenocarcinoma are driven by the androgen receptor, providing opportunities for functional metabolic imaging and novel therapeutic interventions that will be complementary to existing diagnostic and treatment options.

The Relationship Between Prostate Cancer and Metformin Consumption: A Systematic Review and Meta-analysis Study

INTRODUCTION

Prostate cancer is the most common malignant cancer in men worldwide and after lung cancer, it is the second leading cause of cancer mortality in men. The purpose of this study was to investigate the relationship between prostate cancer and metformin consumption in men.

METHODS

The current study is a systematic and meta-analysis review based on the PRISMA statement. To access the studies of domestic and foreign databases, Iran Medex, SID, Magiran, Iran Doc, Medlib, ProQuest, Science Direct, PubMed, Scopus, Web of Science and the Google Scholar search engine were searched during the 2009- 2018 period for related keywords. In order to evaluate the heterogeneity of the studies, Q test and I2 indicator were used. The data were analyzed using the STATA 15.1 software.

RESULTS

In 11 studies with a sample size of 877058, the odds ratio of metformin consumption for reducing prostate cancer was estimated at 0.89 (95%CI: 0.67-1.17). Meta-regression also showed there was no significant relationship between the odds ratio and the publication year of the study. However, there was a significant relationship between the odds ratio and the number of research samples.

CONCLUSION

Using metformin in men reduces the risk of prostate cancer but it is not statistically significant.

Individual and joint effects of metformin and statins on mortality among patients with high-risk prostate cancer

BACKGROUND

Pre-clinical studies suggest that metformin and statins may delay prostate cancer (PCa) metastases; however, data in humans are limited. To the best of our knowledge, this is the first human study aimed to quantify the individual and joint effects of statin and metformin use among patients with high-risk PCa.

METHODS

This population-based retrospective cohort study identified patients from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Exposure to metformin and statins was ascertained from Medicare Prescription Drug Event files. The association with all-cause and PCa mortality were evaluated using Cox proportional hazard model with competing causes of death, where propensity scores were used to adjusted imbalances in covariates across groups.

RESULTS

Based on 12 700 patients with high-risk PCa, statin alone or in combination with metformin was significantly associated with reduced all-cause mortality (Hazard Ratio [HR]: 0.89; 95% Confidence Interval [CI]: 0.83, 0.96; and HR: 0.75; 95% CI, 0.67-0.83, respectively) and PCa mortality (HR, 0.80; 95% CI: 0.69, 0.92) and 0.64; 95% CI, d 0.51-0.81, respectively. The effects were more pronounced in post-diagnostic users: combination use of metformin/statins was associated with a 32% reduction in all-cause mortality (95% CI, 0.57-0.80), and 54% reduction in PCa mortality (95% CI, 0.30-0.69). No significant association of metformin alone was observed with either all-cause mortality or PCa mortality.

CONCLUSIONS

Statin use alone or in combination with metformin was associated with lower all-cause and PCa mortality among high-risk patients, particularly in post-diagnostic settings; further studies are warranted.

Pimozide Inhibits the Human Prostate Cancer Cells Through the Generation of Reactive Oxygen Species

The United States Food and Drug Administration-approved antipsychotic drug, pimozide, has anticancer activities. However, the role of reactive oxygen species (ROS) in its effect on prostate cancer is not well-known. We examined cell proliferation, colony formation, migration, ROS production, and the expression of antioxidant-related genes after treatment of human prostate cancer PC3 and DU145 cells with pimozide. In addition, histopathology, ROS production, and superoxide dismutase (SOD) activity were analyzed after administering pimozide to TRAMP, a transgenic mouse with prostate cancer. Pimozide increased the generation of ROS in both cell lines and inhibited cell proliferation, migration, and colony formation. Oxidative stress induced by pimozide caused changes in the expression of antioxidant enzymes (SOD1, peroxiredoxin 6, and glutathione peroxidase 2) and CISD2. Co-treatment with glutathione, an antioxidant, reduced pimozide-induced ROS levels, and counteracted the inhibition of cell proliferation. Administration of pimozide to TRAMP mice reduced the progression of prostate cancer with increased ROS generation and decreased SOD activity. These results suggest that the antipsychotic drug, pimozide, has beneficial effects in prostate cancer in vivo and in vitro. The mechanism of pimozide may be related to augmenting ROS generation. We recommend pimozide as a promising anticancer agent.

Metformin and statins: a possible role in high-risk prostate cancer

Aim and background

There is increasing evidence that statins and oral anti-diabetic drugs, such as metformin, can have a favorable role in advanced prostate cancer treatment.Metformin has been shown to inhibit proliferation of tumor cells in vitro and statins inhibit carcinogenesis by suppressing angiogenesis/invasion mechanisms. However, clinical evidence on the protective effect of these drugs is still weak.The purpose of this study is to analyze if these drugs have an impact on Biochemical-Failure-Free-Survival (BFFS) and on Distant-Failure-Free-Survival (DFFS) in localized high-risk prostate cancer.

Material and Methods

From 2002-2016, 447 patients with histologically confirmed high-risk prostate cancer were retrospectively evaluated. All patients received radiotherapy and androgen deprivation therapy. Biochemical recurrence was determined by the Phoenix criteria and metastatic patients were defined by the presence of radiological metastasis. Survival analysis was performed using the Kaplan-Meier method.

Results

175 patients were treated with statins (65.3 % with a dose ≤ 20 mg/day) and 70 with metformin (75.7 % with a dose ≤ 1700 mg/day). Median follow-up was 88 months (1-194) with no differences in BFFS and DFFS between metformin and non-metformin patients (77.4 % versus 80 %, p = 0.91 and 89.4 % versus 88.7 %, p = 0.56, respectively). We did not find a statistical difference in BFFS and DFFS in patients taking higher doses of those drugs.

Conclusion

Metformin and statins were not associated with BFFS or DFFS improvement in our analysis. However, the small number of patients treated with these drugs limits the reliability of the results and prospective studies are needed.

YAP Inhibition by Nuciferine via AMPK-Mediated Downregulation of HMGCR Sensitizes Pancreatic Cancer Cells to Gemcitabine

Nuciferine, a major aporphine alkaloid constituent of lotus leaves, is a raw material for obesity treatment. Extensive studies have revealed that obesity is associated with pancreatic cancer (PC). However, it has not been clarified whether nuciferine could be used in PC treatment or prevention. Here, we show that nuciferine could enhance the sensitivity of PC cells to gemcitabine in both cultured cells and the xenograft mouse model. The mechanism study demonstrated that nuciferine induced YAP Ser127 phosphorylation [pYAP(Ser127)] through AMPK-mediated 3-hydroxy-3-methyl-glutaryl-coA reductase (HMGCR) downregulation. Remarkably, wild-type YAP overexpression or YAP Ser127 mutant could resist to nuciferine and no longer sensitize PC cells to gemcitabine. Knockdown of AMPK attenuated pYAP(Ser127) induced by nuciferine. Moreover, knockdown of AMPK reversed nuciferine-mediated HMGCR downregulation. Notably, HMGCR inhibiting could restrain YAP by phosphorylation Ser 127, and therefore enhance the efficiency of gemcitabine in PC cells. In line with this consistent, overexpression of HMGCR reduced growth inhibition caused by nuciferine and/or gemcitabine treatment in PC cells. In summary, these results provide an effective supplementary agent and suggest a therapeutic strategy to reduce gemcitabine resistance in PC.

Study of the Combination of Self-Activating Photodynamic Therapy and Chemotherapy for Cancer Treatment

Cancer is a very challenging disease to treat, both in terms of treatment efficiency and side-effects. To overcome these problems, there have been extensive studies regarding the possibility of improving treatment by employing combination therapy, and by exploring therapeutic modalities with reduced side-effects (such as photodynamic therapy (PDT)). Herein, this work has two aims: (i) to develop self-activating photosensitizers for use in light-free photodynamic therapy, which would eliminate light-related restrictions that this therapy currently possesses; (ii) to assess their co-treatment potential when combined with reference chemotherapeutic agents (Tamoxifen and Metformin). We synthesized three new photosensitizers capable of self-activation and singlet oxygen production via a chemiluminescent reaction involving only a cancer marker and without requiring a light source. Cytotoxicity assays demonstrated the cytotoxic activity of all photosensitizers for prostate and breast tumor cell lines. Analysis of co-treatment effects revealed significant improvements for breast cancer, producing better results for all combinations than just for the individual photosensitizers and even Tamoxifen. By its turn, co-treatment for prostate cancer only presented better results for one combination than for just the isolated photosensitizers and Metformin. Nevertheless, it should be noted that the cytotoxicity of the isolated photosensitizers in prostate tumor cells was already very appreciable.

Main Inflammatory Cells and Potentials of Anti-Inflammatory Agents in Prostate Cancer

Prostate cancer is the most common type of cancer and the leading cause of cancer deaths among men in many countries. Preventing progression is a major concern for prostate cancer patients on active surveillance, patients with recurrence after radical therapies, and patients who acquired resistance to systemic therapies. Inflammation, which is induced by various factors such as infection, microbiome, obesity, and a high-fat diet, is the major etiology in the development of prostate cancer. Inflammatory cells play important roles in tumor progression. Various immune cells including tumor-associated neutrophils, tumor-infiltrating macrophages, myeloid-derived suppressor cells, and mast cells promote prostate cancer via various intercellular signaling. Further basic studies examining the relationship between the inflammatory process and prostate cancer progression are warranted. Interventions by medications and diets to control systemic and/or local inflammation might be effective therapies for prostate cancer progression. Epidemiological investigations and basic research using human immune cells or mouse models have revealed that non-steroidal anti-inflammatory drugs, metformin, statins, soy isoflavones, and other diets are potential interventions for preventing progression of prostate cancer by suppressing inflammation. It is essential to evaluate appropriate indications and doses of each drug and diet.