Anticancer activity of paroxetine in human colon cancer cells: Involvement of MET and ERBB3

The Use of Selective Serotonin Reuptake Inhibitor (SSRI) Antidepressants in the Treatment of Lung Cancer

Lung cancer is among the most common malignancies globally, is frequently associated with a poor prognosis, and is the second leading cause of cancer-related mortality in both genders. Resistance to treatment, heterogeneity, and invasiveness make lung cancer one of the most challenging tumors to combat. Drug repurposing is considered an advantageous strategy for expediting and economizing drug discovery, as it involves rebranding an existing drug for a new therapeutic use. Since depression is a prevalent psychiatric illness among individuals diagnosed with lung cancer, various selective serotonin reuptake inhibitors (SSRIs) used for the treatment of depression were examined for their possible use in lung cancer treatment as repurposed drugs. Herein, we evaluated the efficacy of SSRIs, both alone and in combination with various anticancer agents, in the treatment of lung cancer along with their mechanisms of action. The innovative approach of repurposing SSRIs offers hope by simplifying the drug discovery process and potentially revealing new therapeutic options for lung cancer. Exploring SSRIs' effects on lung cancer treatment may unlock unexpected avenues for combating this aggressive disease.

Unraveling the Anticancer Potential of SSRIs in Prostate Cancer by Combining Computational Systems Biology and In Vitro Analyses

Selective serotonin reuptake inhibitors (SSRIs) are known to have anticancer activity against different types of cancer. In this study, an integrative informatics approach was applied to identify compound and genetic perturbations that produce similar effects to SSRIs to formulate systems biology hypotheses and identify biological pathways involved in the putative anticancer effects of SSRIs in prostate cancer. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay assessed the antiproliferative effects of SSRIs and drug combinations. Cell death mechanisms were studied using annexin V-FITC/PI staining, and the cell cycle analysis was carried out by counterstaining with propidium iodide. Relative gene expression was assessed using a real-time polymerase chain reaction (PCR). Computational results hypothesized that SSRIs could potentially exert anticancer effects in prostate cancer cell lines by modulating apoptotic and tumorigenesis pathways and significantly inhibiting the growth of prostate cancer cells in a time and concentration-dependent manner. The combination of SSRIs with cisplatin, 5-fluorouracil, and raloxifene resulted in either synergistic or additive effects. SSRIs resulted in a significant increase in the early and late apoptotic activity in PC3 cells. Dapoxetine, paroxetine, and sertraline resulted in cell cycle arrest at the G0/G1 phase. Treatment with either dapoxetine or paroxetine decreases the expression of Bcl-2, CASP8, DR5, and VEGF. At the same time, sertraline decreases the expression of Bcl-2 and VEGF and increases the expression of CASP8 and DR5. Results revealed that SSRIs can potentially act as antiproliferative agents against prostate cancer cells, and their activity is mediated through different signaling pathways.

Adverse reactions associated with SSRIs and PD-1/PD-L1 inhibitors: a disproportionality analysis of the FDA Adverse Event Reporting System

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are the primary choice for antidepressant therapy in cancer patients with depression. Programmed death-1 and programmed cell death-ligand 1 (PD-1/PD-L1) play a critical role in immune checkpoint inhibitors. To date, there have been no studies reporting adverse events (AEs) associated with the real-world use of PD-1/PD-L1 inhibitors-SSRIs combination.

RESEARCH DESIGN AND METHODS

This study included a comprehensive evaluation of AE cases covered PD-1/PD-L1 inhibitors-SSRIs combination (first quarter of 2004 to second quarter of 2024) using the FDA Adverse Event Reporting System (FAERS) database, and compared with the use of PD-1/PD-L1 inhibitors or SSRIs alone.

RESULTS

By extracting a total of 807 reports of related AEs, the combination therapy was associated with a distinct AE profile characterized by an increased incidence of immune-related and systemic disorders, as well as a higher signal for adverse pregnancy and perinatal outcomes.

CONCLUSIONS

This study represents the largest report to date on PD-1/PD-L1 inhibitors-SSRIs -related AEs, providing valuable insights into the potential side effects of SSRIs for cancer patients with depression. Clinicians should exercise caution when prescribing SSRIs alongside PD-1/PD-L1 inhibitors, particularly in vulnerable populations such as pregnant women and those with significant comorbidities.

Repurposing of nervous system drugs for cancer treatment: recent advances, challenges, and future perspectives

The nervous system plays a critical role in developmental biology and oncology, influencing processes from ontogeny to the complex dynamics of cancer progression. Interactions between the nervous system and cancer significantly affect oncogenesis, tumor growth, invasion, metastasis, treatment resistance, inflammation that promotes tumors, and the immune response. A comprehensive understanding of the signal transduction pathways involved in cancer biology is essential for devising effective anti-cancer strategies and overcoming resistance to existing therapies. Recent advances in cancer neuroscience promise to establish a new cornerstone of cancer therapy. Repurposing drugs originally developed for modulating nerve signal transduction represent a promising approach to target oncogenic signaling pathways in cancer treatment. This review endeavors to investigate the potential of repurposing neurological drugs, which target neurotransmitters and neural pathways, for oncological applications. In this context, it aims to bridge the interdisciplinary gap between neurology, psychiatry, internal medicine, and oncology. By leveraging already approved drugs, researchers can utilize existing extensive safety and efficacy data, thereby reducing both the time and financial resources necessary for the development of new cancer therapies. This strategy not only promises to enhance patient outcomes but also to expand the array of available treatments, thereby enriching the therapeutic landscape in oncology.

Exposure to Psychotropic Drugs and Colorectal Cancer Risk in Patients with Affective Disorder: A Nested Case-Control Study

BACKGROUND

This study aimed to assess the association between the risk of colorectal cancer (CRC) and exposure to mood stabilizers, antidepressants, and antipsychotics in patients with affective disorders.

METHODS

This nested case-control study used data from the National Health Insurance Database of Taiwan collected between 2001 and 2011. All participants in this study had affective disorders. Then, 1209 patients with CRC and 1:10 matched controls were identified based on their demographic and clinical characteristics. A logistic regression model adjusted for demographic and clinical characteristics was used to determine the risk of developing CRC after exposure to psychotropic drugs.

RESULTS

Among patients with affective disorders, exposure to mood stabilizers (reported as odds ratio; 95% confidence interval; 0.75; 0.57-0.98), antidepressants (0.83; 0.70-0.97), second-generation antipsychotics (0.67; 0.52-0.86), and first-generation antipsychotics (0.65; 0.52-0.81) were associated with a reduced risk of CRC compared to patients who were not exposed. When considering specific drugs, carbamazepine (0.34; 0.12-0.95), valproic acid (0.66; 0.46-0.95), gabapentin (0.44; 0.20-0.99), fluoxetine (0.82; 0.68-0.99), paroxetine (0.63; 0.45-0.87), and venlafaxine (0.72; 0.55-0.95) were associated with a lower risk of CRC.

CONCLUSION

Exposure to psychotropic drugs in patients with affective disorders is associated with a lower risk of CRC compared to those who were not exposed. Although the causal relationship between psychotropic drug exposure and reduced risk of CRC could not be inferred directly, these findings may help clinicians and patients in clinical decision-making.

Current trends and hotspots of depressive disorders with colorectal cancer: A bibliometric and visual study

BACKGROUND

Depression is strongly associated with colorectal cancer (CRC). Few bibliometric analyses have systematically summarized the research focus and recent progress in this field.

AIM

To determine the research status and hotspots by bibliometric analysis of relevant publications on the relationship between CRC and depression.

METHODS

Articles on depression in CRC patients were collected from the Web of Science Core Collection. CiteSpace and VOSviewer software were used to visualize bibliometric networks.

RESULTS

From 2001 to 2022, Supportive Care in Cancer, the United States, Tilburg University, and Mols were the most productive and influential journal, country, institution, and author name. Co-occurrence cluster analysis of keywords placed quality of life, anxiety, and psychological stress in the center of the visual network diagram. Further clustering was performed for the clusters with studies of the relevant mechanism of action, which showed that: (1) Cytokines have a role essential for the occurrence and development of depressive disorders in CRC; (2) MicroRNAs have a role essential for the development of depressive disorders in CRC; (3) Some anticancer drugs have pro-depressant activity; and (4) Selective serotonin reuptake inhibitors have both antitumor and antidepressant activity.

CONCLUSION

Life quality and psychological nursing of the cancer population were key topics. The roles of cytokines and microRNAs, the pro-depression activity of anticancer drugs and their antitumor properties deserve in-depth study.

Beyond Psychotropic: Potential Repurposing of Fluoxetine toward Cancer Therapy

Drug repurposing, rebranding an existing drug for a new therapeutic indication, is deemed a beneficial approach for a quick and cost-effective drug discovery process by skipping preclinical, Phase 1 trials and pharmacokinetic studies. Several psychotropic drugs, including selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), were studied for their potential application in different diseases, especially in cancer therapy. Fluoxetine (FLX) is one of the most prescribed psychotropic agents from the SSRIs class for the treatment of several neuropsychiatric disorders with a favorable safety profile. FLX exhibited different oncolytic effects via mechanisms distinct from its main serotonergic activity. Taking advantage of its ability to rapidly penetrate the blood-brain barrier, FLX could be particularly useful in brain tumors. This was proved by different in vitro and in vivo experiments using FLX as a monotherapy or combination with temozolomide (TMZ) or radiotherapy. In this review of the literature, we summarize the potential pleiotropic oncolytic roles of FLX against different cancers, highlighting the multifaceted activities of FLX and its ability to interrupt cancer proliferation via several molecular mechanisms and even surmount multidrug resistance (MDR). We elaborated on the successful synergistic combinations such as FXR/temozolomide and FXR/raloxifene for the treatment of glioblastoma and breast cancer, respectively. We showcased beneficial pharmaceutical trials to load FLX onto carriers to enhance its safety and efficacy on cancer cells. This is the first review article extensively summarizing all previous FLX repurposing studies for the management of cancer.

Prevalence and implications of pKs-positive Escherichia coli in colorectal cancer

Colorectal cancer (CRC) remains a significant global health concern, necessitating continuous investigation into its etiology and potential risk factors. Recent research has shed light on the potential role of pKs-positive Escherichia coli (pKs + E. coli) and colibactin in the development and progression of CRC. Therefore, this review aimed to provide an updated analysis of the prevalence and implications of pKs + E. coli in colorectal cancer. We conducted a literature review search in major scientific databases to identify relevant studies exploring the association between pKs + E. coli and CRC. The search strategy included studies published up to the present date, and articles were carefully selected based on predefined inclusion criteria. Thus, the present study encompasses scientific evidence from clinical and epidemiological studies supporting the presence of pKs + E. coli in CRC patients, demonstrating a consistent and significant association in multiple studies. Furthermore, we highlighted the potential mechanisms by which colibactin may promote tumorigenesis and cancer progression within the colorectal mucosa, including the production of genotoxic virulence factors. Additionally, we explored current diagnostic methods for detecting pKs + E. coli in clinical settings, emphasizing the importance of accurate identification. Moreover, we discussed future strategies that could utilize the presence of this strain as a biomarker for CRC diagnosis and treatment. In conclusion, this review consolidated existing evidence on the prevalence and implications of pKs + E. coli in colorectal cancer. The findings underscore the importance of further research to elucidate the precise mechanisms linking this strain to CRC pathogenesis and to explore its potential as a therapeutic target or diagnostic marker. Ultimately, a better understanding of the role of pKs + E. coli in CRC may pave the way for innovative strategies in CRC management and patient care.

Inhibition of TNBC Cell Growth by Paroxetine: Induction of Apoptosis and Blockage of Autophagy Flux

The strategy of drug repurposing has gained traction in the field of cancer therapy as a means of discovering novel therapeutic uses for established pharmaceuticals. Paroxetine (PX), a selective serotonin reuptake inhibitor typically utilized in the treatment of depression, has demonstrated promise as an agent for combating cancer. Nevertheless, the specific functions and mechanisms by which PX operates in the context of triple-negative breast cancer (TNBC) remain ambiguous. This study aimed to examine the impact of PX on TNBC cells in vitro as both a standalone treatment and in conjunction with other pharmaceutical agents. Cell viability was measured using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, apoptosis was assessed through flow cytometry, and the effects on signaling pathways were analyzed using RNA sequencing and Western blot techniques. Furthermore, a subcutaneous tumor model was utilized to assess the in vivo efficacy of combination therapy on tumor growth. The results of our study suggest that PX may activate the Ca2+-dependent mitochondria-mediated intrinsic apoptosis pathway in TNBC by potentially influencing the PI3K/AKT/mTOR pathway as well as by inducing cytoprotective autophagy. Additionally, the combination of PX and chemotherapeutic agents demonstrated moderate inhibitory effects on 4T1 tumor growth in an in vivo model. These findings indicate that PX may exert its effects on TNBC through modulation of critical molecular pathways, offering important implications for improving chemosensitivity and identifying potential therapeutic combinations for clinical use.

A Surprising Repurposing of Central Nervous System Drugs against Squamous Cell Carcinoma of the Bladder, UM-UC-5

The potential benefits of drug repurposing have gained attention as an alternative to developing de novo drugs. The potential of using central nervous system (CNS) drugs as anticancer drugs has been explored in several types of human cancers, such as breast and colon cancer, among others. Here, we examine the effect of the CNS drugs sertraline, paroxetine, and chlorpromazine on human squamous carcinoma cells of the bladder (UM-UC-5). After exposing UM-UC-5 cells to increased concentrations of each drug for 48 h, we assessed their metabolic activity using an MTT assay. Based on those results, we calculated cell viability and the half-maximal inhibitory concentration (IC50) values. The results suggest that the CNS drugs were effective against UM-UC-5 in the order of potency of sertraline > chlorpromazine > paroxetine. Interestingly, sertraline was more potent than 5-fluorouracil (5-FU), a widely used anticancer drug. This study demonstrated, for the first time, the promising anticancer activity of CNS drugs on human bladder cancer cells in vitro and supports the repurposing of CNS drugs to improve cancer treatment. Nevertheless, further studies are necessary to understand their mechanism of action and in vivo activity.

Fundamental Uses of Peptides as a New Model in Both Treatment and Diagnosis

An amino acid short chain is known as a peptide. Peptide bonds are the connections that hold the amino acids of a peptide together in a particular order. Characteristically, the shorter length of peptides helps to identify them from proteins. Different ways are used to classify peptides, including chain length, source of peptides, or their biological functions. The fact that peptides serve several purposes suggests that there is a foundation for improvement in peptide production and structure to enhance action. In addition, many patents on peptides for therapeutic and diagnostic approaches have been obtained. This review aims to give an overview of peptides used recently in treatment and diagnosis.

Drug repurposing for the identification of new Bcl-2 inhibitors: In vitro, STD-NMR, molecular docking, and dynamic simulation studies

BACKGROUND

The anti-apoptotic protein B-Cell Lymphoma 2 (Bcl-2) is a key target for the development of anti-cancer agents, as its overexpression can render cancer cells resistant to chemotherapeutic treatments.

AIMS AND OBJECTIVES

The current study has systematically evaluated a library of FDA-approved drugs for Bcl-2 inhibition using a drug repurposing strategy via in vitro, biophysical, and in-silico techniques.

MATERIALS AND METHODS

In vitro anticancer activity was performed, followed by apoptosis assay. The selected compounds were subjected to Saturation Transfer Difference Nuclear Magnetic Resonance (STD-NMR) spectroscopy, molecular docking, and molecular dynamic simulation for ligand-protein interactions.

KEY FINDINGS

In the initial screening, seventy-five (75) drugs were evaluated against the HL-60 (human blood promyelocytic leukemia) cancer cell line. Among them, paroxetine HCl, carvedilol, clomipramine HCl, and clomifene citrate showed significant anti-proliferative activity (IC50 = 9.733 ± 0.524, 11.940 ± 0.079, 12.376 ± 1.242, and 6.155 ± 0.363 μM, respectively), in comparison to the reference drug venetoclax (IC50 = 7.086 ± 0.041 μM). This indicated that the test drugs have comparable IC50 values to the standard drug. Furthermore, the drugs were able to induce apoptosis in HL-60 cells. These drugs showed interactions with Bcl-2 protein in STD-NMR analysis. Docking and MD simulation studies further supported the interaction of these drugs with Bcl-2 protein, mainly via hydrophobic contacts leading to stable drug-Bcl-2 complexes.

SIGNIFICANCE

This study, identifies paroxetine HCl, carvedilol, clomipramine HCl, and clomifene citrate as significant Bcl-2 inhibitors and needs further pre-clinical and clinical studies for potential anti-cancer agents' evaluation.

Fluoxetine inactivates STAT3/NF-κB signaling and promotes sensitivity to cisplatin in bladder cancer

Bladder cancer is known as one of the top ten most common cancer types worldwide and can be majorly divided into muscles invasive bladder cancer (MIBC) and non-muscles invasive type (NMIBC). However, the prognosis of BC remains poor under standard treatment including radical cystectomy or concurrent chemoradiotherapy. Numerous studies have reported that the prognosis of BC is associated with the activation of signal transducer and activator of transcription (STAT3) and nuclear factor kappa-B (NF-κB). Fluoxetine, a well-known anti-depressant, has been reported to against various type of cancers. However, it is unclear whether fluoxetine has the capacity to inhibit BC progression by targeting STAT3 and NF-κB-mediated signaling. Here, we used cell viability, apoptosis assay, wound healing assay, invasion/migration assay, Western blotting assay, immunofluorescence staining, as well as animal experiments, to elucidate the efficacy of fluoxetine on in vitro and in vivo BC models. We found that fluoxetine may induce cytotoxicity and intrinsic/extrinsic apoptosis in BC and enhance the potential of cisplatin. Fluoxetine promoted both caspase-dependent and caspase-independent apoptosis signaling by activating caspase-3, 8, 9, apoptosis-inducing factor (AIF), and EndG. Furthermore, fluoxetine suppressed invasion and migration ability and the expression of metastasis-associated genes. Fluoxetine was also found to inactivate the phosphorylation of STAT3 (Tyr705) and NF-κB (Ser536) and suppress the nuclear translocation of NF-κB. In MB49-bearing mice, fluoxetine effectively delayed the progression of BC without inducing general toxicity. In summary, the induction of apoptosis and the inhibition of invasion triggered by fluoxetine are associated with the inactivation of STAT3 and NF-κB.

Anticancer effect of paroxetine and amitriptyline on HT29 and A549 cell lines

INTRODUCTION

Paroxetine is functionally classified as a selective serotonin reuptake inhibitor. Paroxetine can induce mitochondria-dependent apoptosis through the ROS-MAPK pathway.Amitriptyline is a tricyclic antidepressant. This drug induces the expression of p53, thereby activating caspase-3. Amitriptyline has also been studied as a potential candidate for inducing oxidative stress and cytotoxicity in cancer cells, which may be more effective than other chemotherapy drugs. This study aims to to investigate the anticancer effects of paroxetine and amitriptyline and their combination treatment on HT29 and A549 cell lines for the first time.

METHODS

In order to investigate the anticancer effect of two drugs, paroxetine and amitriptyline, on inhibiting the growth of A549 and HT29 cancer cells, oxidative stress factors and LDH enzyme and apoptosis tests were performed.

RESULTS

Two drugs, amitriptyline and paroxetine alone, inhibited the growth of cancer cells in such a way that the inhibitory effect of the cells increased with the increase in the dose of the drug. In the simultaneous exposure of these two drugs, the inhibitory effect was much greater than the effect of single drug exposure. Also, these two drugs have caused LDH leakage and induction of apoptosis.

CONCLUSION

According to the results of the study, it was found that these two drugs have the necessary ability to inhibit the growth of cancer cells by inducing apoptosis and LDH leakage and inducing oxidative stress.

Multimodal representation learning for predicting molecule-disease relations

MOTIVATION

Predicting molecule-disease indications and side effects is important for drug development and pharmacovigilance. Comprehensively mining molecule-molecule, molecule-disease and disease-disease semantic dependencies can potentially improve prediction performance.

METHODS

We introduce a Multi-Modal REpresentation Mapping Approach to Predicting molecular-disease relations (M2REMAP) by incorporating clinical semantics learned from electronic health records (EHR) of 12.6 million patients. Specifically, M2REMAP first learns a multimodal molecule representation that synthesizes chemical property and clinical semantic information by mapping molecule chemicals via a deep neural network onto the clinical semantic embedding space shared by drugs, diseases and other common clinical concepts. To infer molecule-disease relations, M2REMAP combines multimodal molecule representation and disease semantic embedding to jointly infer indications and side effects.

RESULTS

We extensively evaluate M2REMAP on molecule indications, side effects and interactions. Results show that incorporating EHR embeddings improves performance significantly, for example, attaining an improvement over the baseline models by 23.6% in PRC-AUC on indications and 23.9% on side effects. Further, M2REMAP overcomes the limitation of existing methods and effectively predicts drugs for novel diseases and emerging pathogens.

AVAILABILITY AND IMPLEMENTATION

The code is available at https://github.com/celehs/M2REMAP, and prediction results are provided at https://shiny.parse-health.org/drugs-diseases-dev/.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Repurposing Antidepressants and Phenothiazine Antipsychotics as Efflux Pump Inhibitors in Cancer and Infectious Diseases

Multidrug resistance (MDR) is a major obstacle in the therapy of infectious diseases and cancer. One of the major mechanisms of MDR is the overexpression of efflux pumps (EPs) that are responsible for extruding antimicrobial and anticancer agents. EPs have additional roles of detoxification that may aid the development of bacterial infection and the progression of cancer. Therefore, targeting EPs may be an attractive strategy to treat bacterial infections and cancer. The development and discovery of a new drug require a long timeline and may come with high development costs. A potential alternative to reduce the time and costs of drug development is to repurpose already existing drugs. Antidepressants and antipsychotic agents are widely used in clinical practice in the treatment of psychiatric disorders and some somatic diseases. Antidepressants and antipsychotics have demonstrated various beneficial activities that may be utilized in the treatment of infections and cancer. This review aims to provide a brief overview of antibacterial and anticancer effects of selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs) and phenothiazine antipsychotics, while focusing on EPs. However, it should be noted that the antimicrobial activity of a traditionally non-antibiotic drug may have clinical implications regarding dysbiosis and bacterial MDR.

The application of antidepressant drugs in cancer treatment

Antidepressants refer to psychotropic drugs which are used to treat mental illness with prominent emotional depression symptoms. It was reported that antidepressants had associated with anti-carcinogenic function which was associated with various signaling pathways and changing of microenvironment. Its mechanism includes cell apoptosis, antiproliferative effects, mitochondria-mediated oxidative stress, DNA damaging, changing of immune response and inflammatory conditions, and acting by inhibiting multidrug resistance of cancer cells. Accumulated studies showed that antidepressants influenced the metabolic pathway of tumor cells. This review summarized recent developments with the impacts and mechanisms of 10 kinds of antidepressants in carcinostasis. Antidepressants are also used in combination therapy with typical anti-tumor drugs which shows a synergic effect in anti-tumor. By contrast, the promotion roles of antidepressants in increasing cancer recurrence risk, mortality, and morbidity are also included. Further clinical experiments and mechanism analyses needed to be achieved. A full understanding of the underlying mechanisms of antidepressants-mediated anticarcinogenic effects may provide new clues for cancer prevention and clinical treatment.

An overall assessment of the effects of antidepressant paroxetine on aquatic organisms and human cells

Paroxetine (PRX) is one of the most used antidepressants and an emerging contaminant with potential harmful effects to the environment and human health. The present study investigates in detail the toxic potential of PRX using a battery of bioassays on fresh- and marine species, marine bacteria, and human lymphocytes. All the tested organisms and human lymphocytes were exposed at concentrations ranging from μg L^-1 to mg L^-1. It was found that PRX can cause toxic effects to aquatic organisms at environmental relevant concentrations (μg L^-1 level). A significant effect of PRX was observed in all tested algal species especially at the first 24 h. However, differences in responses and sensitivities among the tested algal species were observed. The most sensitive organism was found to be Dunaliella tertiolecta with IC₅₀ = 0.092 mg L^-1 (72 h). In the case of Aliivibrio fischeri, EC₅₀ values were determined to be 16.65, 14.31 and 14.41 mg L^-1 for 5, 15 and 30 min of exposure, respectively. PRX also induced cytotoxic and genotoxic effects in human lymphocytes. A dose-dependent increase in micronucleus frequencies was occurred at all tested concentrations with a statistically significant increase in micronucleus frequencies at the medium to high PRX tested concentrations. The findings of the present study expand the available toxicity profile of PRX on aquatic organisms and the knowledge about the potential risk of PRX to induce genotoxic effects in cultured human lymphocytes.

Oxaliplatin-loaded nanoemulsion containing Teucrium polium L. essential oil induces apoptosis in Colon cancer cell lines through ROS-mediated pathway

Oxaliplatin (Oxa)-associated adverse side effects have considerably limited the clinical use of the drug in colon cancer therapy. Mutant p53 has diverse mutational profiles in colon cancer, and it influences the potencies of various chemotherapeutic drugs, including Oxa. Thus, it would be highly beneficial to identify an alternative therapeutic strategy that not only reduces the toxicity of Oxa, but also exerts a synergistic effect against colon cancers, regardless of their p53 profiles. The present study was aimed at preparing and optimizing Teucrium polium L. essential oil nanoemulsion (TPO-NANO) and investigating its effect on the sensitivity of colon cancer cells with differences in p53 status (HCT116 wild-type and HT-29 mutant-type) to Oxa. The viability of treated cells was determined and the combination index (CI) was calculated. Morphological changes were determined under inverted microscopy, while percentage apoptosis was assayed using flow cytometry. Intracellular ROS and the protein levels of p53 and Bax were measured. The colony-forming potential of treated cells was determined using colony assay. The size of TPO-NANO was markedly increased from 12.90 ± 0.04 nm to 14.47 ± 0.53 nm after loading Oxa (p ≤ 0.05). The combination (Oxa + TPO-NANO) produced a synergetic effect in HCT116 and HT-29, with CI of 0.94 and 0.88, respectively. Microscopic examination and flow cytometric analysis revealed that cells treated with Oxa + TPO-NANO had a higher percentage of apoptosis than cells exposed to monotherapy. Cumulatively, Oxa exerted an apoptotic effect on wild or mutant p53 colon cancer cells when combined with TPO-NANO, through a mechanism involving ROS-mediated mitochondrial apoptosis.

Use of Selective Serotonin Reuptake Inhibitors Is Associated with a Lower Risk of Colorectal Cancer among People with Family History

Individuals with a family history of colorectal cancer (CRC) are at a high risk of developing CRC. Preclinical and population-based evidence suggests that selective serotonin reuptake inhibitors (SSRIs) might play a role in preventing CRC. We performed a nationwide cohort study to explore whether the use of SSRIs could reduce CRC risk among individuals with family history. We identified individuals aged 50 and above who had one or more first-degree relatives diagnosed with CRC. A total of 38,617 incident SSRI users were identified and matched with 115,851 non-users, on a ratio of 1:3. The Cox regression model was used to calculate hazard ratios (HRs) and 95% CI confidence intervals (CIs). We found a significant negative association between SSRI use and the risk of CRC (adjusted HR, 0.77; 95% CI, 0.70-0.85). Restricted cubic spline regression showed a non-linear dose-responded relationship between SSRI use and CRC risk. The association was stronger in rectal cancer than colon cancer (adjusted HR, 0.73 vs. 0.79), and more pronounced in advanced-stage CRC than early-stage CRC (adjusted HR, 0.73 vs. 0.80). This population-based cohort study suggests that the use of SSRIs is associated with a reduced risk of CRC among individuals with a family history of CRC.

DNA repair proteins as the targets for paroxetine to induce cytotoxicity in gastric cancer cell AGS

To evaluate the potential anticancer effects of 1175 FDA-approved drugs, cell viability screening was performed using 25 human cancer cell lines covering 14 human cancer types. Here, we focus on the action of paroxetine, which demonstrated greater toxicity toward human gastric adenocarcinoma cell-line AGS cells compared with the other FDA-approved drugs, exhibiting an IC50 value lower than 10 μM. Evaluation of the underlying novel mechanisms revealed that paroxetine can enhance DNA damage in gastric cancer cells and involves downregulation of Rad51, HR23B and ERCC1 expression and function, as well as nucleotide shortage. Enhancement of autophagy counteracted paroxetine-induced apoptosis but did not affect paroxetine-induced DNA damage. Paroxetine also enhanced ROS generation in AGS cells, but a ROS scavenger did not improve paroxetine-mediated DNA damage, apoptosis, or autophagy, suggesting ROS might play a minor role in paroxetine-induced cell toxicity. In contrast, paroxetine did not enhance DNA damage, apoptosis, or autophagy in another insensitive gastric adenocarcinoma cell-line MKN-45 cells. Interestingly, co-administration of paroxetine with conventional anticancer agents sensitized MKN-45 cells to these agents: co-treated cells showed increased apoptosis relative to MKN-45 cells treated with the anticancer agent alone. Unequivocally, these data suggest that for the first time that paroxetine triggers cytotoxicity and DNA damage in AGS cells at least partly by reducing the gene expression of Rad51, HR23B, and ERCC1. Our findings also suggest that paroxetine is a promising candidate anticancer agent and/or chemosensitizing agent for use in combination with other anticancer drugs in cancer therapy. The molecular mechanisms underlying the anticancer activity of co-treatment with paroxetine and chemotherapy appear to be complex and are worthy of further investigation.

Complex Effects of Sertraline and Citalopram on In Vitro Murine Breast Cancer Proliferation and on In Vivo Progression and Anxiety Level

Some selective serotonin reuptake inhibitors (SSRIs), primarily sertraline, demonstrate anti-proliferative activity in malignant cell-lines and in xenografted mouse models of colorectal tumor. There is, however, a paucity of comparative studies on the anti-tumor effects of SSRIs. We compared the in vitro and in vivo effects of sertraline and citalopram on murine 4T1 breast cancer. Grafted mice were used to determine the rate of tumor growth and survival as well as the impact of stress and antidepressant treatment on tumor progression and mortality and on pro-inflammatory cytokines. Sertraline, in the micromolar range, but not citalopram, induced a significant in vitro concentration-dependent inhibition of murine 4T1 cell proliferation and splenocyte viability. In contrast, sertraline (10 mg/kg/d), enhanced in vivo tumor growth. Contrary to the study's hypothesis, chronic mild stress did not modify tumor growth in grafted mice. The in vitro effects of sertraline on tumor growth seem to be the opposite of its in vivo effects. The impact of sertraline treatment on humans with breast cancer should be further investigated.

Paroxetine mitigates cardiac remodelling by doxorubicin and increases survival

Doxorubicin (DOX) is an effective anticancer drug. However, its use is hampered by the development of very mortal cardiomyopathy. Here, we investigate whether the co-administration of the antidepressant paroxetine (P), known to exert beneficial cardiovascular effects, would provide effective cardioprotection. Experiments were performed in male Wistar rats randomly assigned to control group (0.5 mL/kg 0.9% NaCl, i.v., n = 7), DOX group (DOX 5 mg /kg i.v., n = 23) and DOX+P group (DOX 5 mg/kg, i.v. plus P 10 mg/kg p.o. daily, beginning five days before DOX administration and during the follow-up period, n = 11). Rats' body weight and echocardiography parameters were monitored before and after drug/vehicle administration. Cardiac histology was performed post-mortem, as well as beta1-adrenergic receptor (β₁-AR), beta2-adrenergic receptor (β₂-AR), G protein-coupled receptor kinases type 2 (GRK2), type 3 (GRK3), beta-arrestin 1, and beta-arrestin 2 gene expression using RT-qPCR. DOX-treated rats exhibited bad general condition, adynamia, loss of body weight, and low survival. Echocardiography revealed two phenotypes: cardiomyopathy with left ventricular (LV) hypertrophy (DOX-HCM) and cardiomyopathy with LV dilation (DOX-DCM). In DOX-HCM rats only, there was an increased GRK2 and GRK3 gene expression and synthesis. DOX+P co-treated rats exhibited good general condition, normal spontaneous behaviour, gained weight over time, had increased survival, and preserved LV morphology and contractility. In these rats, gene expression and synthesis of GRK2 and GRK3 were decreased, while β₁-AR and β₂-AR were increased. Present results show for the first time that P effectively reduces DOX-induced cardiotoxicity and enhances survival.

Repurposing antidepressants for anticancer drug discovery

Drug repurposing is an attractive strategy for identifying new indications for existing drugs. Three approved antidepressants have advanced into clinical trials for cancer therapy. In particular, further medicinal chemistry efforts with tranylcypromine (TCP) have led to the discovery of several TCP-based histone lysine specific demethylase 1 (LSD1) inhibitors that display therapeutic promise for treating cancer in the clinic. Thus repurposing antidepressants could be a promising strategy for cancer treatment. In this review, we illustrate the anticancer mechanisms of action of antidepressants and also discuss the challenges and future directions of repurposing antidepressants for anticancer drug discovery, to provide an overview of approved antidepressant cancer therapies.

Purified recombinant human Chromogranin A N46 peptide with remarkable anticancer effect on human colon cancer cells

Human Chromogranin A N46 (CGA-N46) is a weak cationic α-helical peptide with wide-spectrum antibacterial, fungal, and anticancer activities. In this study, the recombinant human CGA-N46 peptide was expressed successfully in Escherichia coli. The gene of CGA-N46 was cloned into the expression vector pET-15b without a fusion tag at the N terminus and the peptide was expressed using Isopropyl-β-d-thiogalactoside (IPTG) as an inducer. Using 8 M guanidinium HCl, inclusion bodies containing the peptide were purified and solubilized. The rhCGA-N46 peptide was purified using Q-FF anion exchange column. The cytotoxicity of the purified rhCGA-N46 peptide was investigated on WI-38 human lung normal cell line. The anticancer activity was studied on human colon cancer cell line; HCT-116 cell line. Besides, the possible involvement of rhCGA-N46 peptide in regulating apoptotic signal pathways was analyzed by detecting the expression levels of BCL2, BID, and CAS-8 in the treated cells. The results concluded that the active peptide recovery was up to 41.98%. The purified rhCGA-N46 was safe on normal cells with IC₅₀ = 227.74 µg/ml (40.67 µM) and had an obvious anticancer effect on colon cancer cells with IC₅₀ = 1.997 µg/ml (356.6 nM). The expression level of BCL2 was down-regulated and BID and CAS-8 were up-regulated significantly in treated HCT-116 cells compared to untreated. In conclusion, the rhCGA-N46 peptide was produced successfully in the native form with promising anti-colon cancer activity.

Antidepressants with anti-tumor potential in treating glioblastoma: A narrative review

Glioblastoma multiforme (GBM) is known as the deadliest form of brain tumor. In addition, its high treatment resistance, heterogeneity, and invasiveness make it one of the most challenging tumors. Depression is a common psychological disorder among patients with cancer, especially GBM. Due to the high occurrence rates of depression in GBM patients and the overlap of molecular and cellular mechanisms involved in the pathogenesis of these diseases, finding antidepressants with antitumor effects could be considered as an affordable strategy for the treatment of GBM. Antidepressants exert their antitumor properties through different mechanisms. According to available evidence in this regard, some of them can eliminate the adverse effects resulting from chemo-radiotherapy in several cancers along with their synergistic effects caused by chemotherapy. Therefore, providing comprehensive insight into this issue would guide scientists and physicians in developing further preclinical studies and clinical trials, in order to evaluate antidepressants' antitumor potential. Considering that no narrative review has been recently published on this issue, specifically on these classes of drugs, we present this article with the purpose of describing the antitumor cellular mechanisms of three classes of antidepressants as follows: tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and monoamine oxidase inhibitors (MAOIs) in GBM.

Phyto-Phospholipid Complexation as a Novel Drug Delivery System for Management of Cancer with Better Bioavailability: Current Perspectives and Future Prospects

Cancer is the foremost cause of death, and it supports the need for the identification of novel anticancer drugs to improve the efficacy of current-therapy. While the synthetic anticancer drug is associated with numerous side effects. Hence the plant active or phytoconstituents are in high demand for the treatment of cancer due to minimum side effects. But the polar nature of phytoconstituents hindered the absorption of the drug and lowered the therapeutic efficacy. The plant activity incorporated into Phyto-phospholipid Complexation can enhance bioavailability and improved therapeutic efficacy. In this review article, advantages, limitation and application of Phyto-phospholipid complexes have been illustrated. The article highlights the application of Phyto-phospholipid complexes as a promising drug carrier system to treat cancer.

Drug Repurposing in Oncology: Current Evidence and Future Direction

BACKGROUND

Drug repurposing, the application of known drugs and compounds with a primary non-oncology purpose, might be an attractive strategy to offer more effective treatment options to cancer patients at a low cost and reduced time.

METHODS

This review described a total of 10 kinds of non-oncological drugs from more than 100 mechanical studies as well as evidence from population-based studies. The future direction of repurposed drug screening is discussed by using patient-derived tumor organoids.

RESULTS

Many old drugs showed previously unknown effects or off-target effects and can be intelligently applied for cancer chemoprevention and therapy. The identification of repurposed drugs needs to combine evidence from mechanical studies and population-based studies. Due to the heterogeneity of cancer, patient-derived tumor organoids can be used to screen the non-oncological drugs in vitro.

CONCLUSION

These identified old drugs could be repurposed in oncology and might be added as adjuvants and finally benefit patients with cancers.

Antidepressants and Antipsychotic Agents as Repurposable Oncological Drug Candidates

Drug repurposing, also known as drug repositioning/reprofiling, is a relatively new strategy for the identification of alternative uses of well-known therapeutics that are outside the scope of their original medical indications. Such an approach might entail a number of advantages compared to standard de novo drug development, including less time needed to introduce the drug to the market, and lower costs. The group of compounds that could be considered as promising candidates for repurposing in oncology include the central nervous system drugs, especially selected antidepressant and antipsychotic agents. In this article, we provide an overview of some antidepressants (citalopram, fluoxetine, paroxetine, sertraline) and antipsychotics (chlorpromazine, pimozide, thioridazine, trifluoperazine) that have the potential to be repurposed as novel chemotherapeutics in cancer treatment, as they have been found to exhibit preventive and/or therapeutic action in cancer patients. Nevertheless, although drug repurposing seems to be an attractive strategy to search for oncological drugs, we would like to clearly indicate that it should not replace the search for new lead structures, but only complement de novo drug development.

Nuisance compounds in cellular assays

Compounds that exhibit assay interference or undesirable mechanisms of bioactivity ("nuisance compounds") are routinely encountered in cellular assays, including phenotypic and high-content screening assays. Much is known regarding compound-dependent assay interferences in cell-free assays. However, despite the essential role of cellular assays in chemical biology and drug discovery, there is considerably less known about nuisance compounds in more complex cell-based assays. In our view, a major obstacle to realizing the full potential of chemical biology will not just be difficult-to-drug targets or even the sheer number of targets, but rather nuisance compounds, due to their ability to waste significant resources and erode scientific trust. In this review, we summarize our collective academic, government, and industry experiences regarding cellular nuisance compounds. We describe assay design strategies to mitigate the impact of nuisance compounds and suggest best practices to efficiently address these compounds in complex biological settings.

Paroxetine-Overview of the Molecular Mechanisms of Action

In the 21st century and especially during a pandemic, the diagnosis and treatment of depression is an essential part of the daily practice of many family doctors. It mainly affects patients in the age category 15–44 years, regardless of gender. Anxiety disorders are often diagnosed in children and adolescents. Social phobias can account for up to 13% of these diagnoses. Social anxiety manifests itself in fear of negative social assessment and humiliation, which disrupts the quality of social functioning. Treatment of the above-mentioned disorders is based on psychotherapy and pharmacotherapy. Serious side effects or mortality from antidepressant drug overdose are currently rare. Recent studies indicate that paroxetine (ATC code: N06AB), belonging to the selective serotonin reuptake inhibitors, has promising therapeutic effects and is used off-label in children and adolescents. The purpose of this review is to describe the interaction of paroxetine with several molecular targets in various points of view including the basic chemical and pharmaceutical properties. The central point of the review is focused on the pharmacodynamic analysis based on the molecular mechanism of binding paroxetine to various therapeutic targets.

Selective serotonin reuptake inhibitors use and hepatocellular carcinoma in patients with alcohol use disorder

BACKGROUND

Research has proposed that selective serotonin reuptake inhibitors (SSRIs) were associated with a reduction of the risk of hepatocellular carcinoma (HCC). The objective of this study is to investigate whether SSRIs use is associated with decreased risk of HCC in patients with alcohol use disorder (AUD).

PATIENTS AND METHODS

We conducted a retrospective population-based cohort study using Taiwan's National Health Insurance Research Database (NHIRD) from 1997 to 2013 and enrolled patients with newly diagnosed AUD. After propensity scores matching at a ratio 1:4, total of 4945 SSRI users and 19,785 non-SSRI users were included in the matched cohort. Patients were followed up from the 365th day after the date of first exposure to SSRIs to occurrence of HCC, the date of death, or the end of 2013. Cox proportional hazard regressions were performed to evaluate hazard ratio (HRs) for HCC in SSRI-exposed patients compared with unexposed patients.

RESULTS

In the main study cohort, SSRI use was associated with significant lower risk of HCC compared to the non-SSRI users after adjusting for age, sex, income, urbanization, alcoholic fatty liver, alcoholic hepatitis and diabetes (adjusted hazard ratio [aHR] = 0.31, 95 % CI = 0.24-0.39). The negative association of SSRI use and HCC was replicated in the matched cohort (aHR = 0.58, 95 % CI = 0.44-0.77). The effect of SSRI use on HCC was dose-related in both cohorts (p for trend < 0.0001).

CONCLUSIONS

This study showed that SSRIs use was associated with a reduction risk of HCC among AUD patients in a cumulative dose effect manner.

Inhibition of G Protein-Coupled Receptor Kinase 2 Promotes Unbiased Downregulation of IGF1 Receptor and Restrains Malignant Cell Growth

The ability of a receptor to preferentially activate only a subset of available downstream signal cascades is termed biased signaling. Although comprehensively recognized for the G protein-coupled receptors (GPCR), this process is scarcely explored downstream of receptor tyrosine kinases (RTK), including the cancer-relevant insulin-like growth factor-1 receptor (IGF1R). Successful IGF1R targeting requires receptor downregulation, yet therapy-mediated removal from the cell surface activates cancer-protective β-arrestin-biased signaling (β-arr-BS). As these overlapping processes are initiated by the β-arr/IGF1R interaction and controlled by GPCR-kinases (GRK), we explored GRKs as potential anticancer therapeutic targets to disconnect IGF1R downregulation and β-arr-BS. Transgenic modulation demonstrated that GRK2 inhibition or GRK6 overexpression enhanced degradation of IGF1R, but both scenarios sustained IGF1-induced β-arr-BS. Pharmacologic inhibition of GRK2 by the clinically approved antidepressant, serotonin reuptake inhibitor paroxetine (PX), recapitulated the effects of GRK2 silencing with dose- and time-dependent IGF1R downregulation without associated β-arr-BS. In vivo, PX treatment caused substantial downregulation of IGF1R, suppressing the growth of Ewing's sarcoma xenografts. Functional studies reveal that PX exploits the antagonism between β-arrestin isoforms; in low ligand conditions, PX favored β-arrestin1/Mdm2-mediated ubiquitination/degradation of IGF1R, a scenario usually exclusive to ligand abundancy, making PX more effective than antibody-mediated IGF1R downregulation. This study provides the rationale, molecular mechanism, and validation of a clinically feasible concept for "system bias" targeting of the IGF1R to uncouple downregulation from signaling. Demonstrating system bias as an effective anticancer approach, our study reveals a novel strategy for the rational design or repurposing of therapeutics to selectively cross-target the IGF1R or other RTK. SIGNIFICANCE: This work provides insight into the molecular and biological roles of biased signaling downstream RTK and provides a novel "system bias" strategy to increase the efficacy of anti-IGF1R-targeted therapy in cancer.

Association between selective serotonin reuptake inhibitors and kidney cancer risk: A nationwide population-based cohort study

The association between selective serotonin reuptake inhibitor (SSRI) exposure and cancer incidence has been investigated; however, no epidemiological study has investigated the association between exposure to individual SSRIs and kidney cancer incidence. The aim of this study is to examine whether SSRI use affected the risk of kidney cancer. We conducted a population-based retrospective cohort study using data from Taiwan's National Health Insurance Research Database. After adjusting for sex, age, urbanization level, comorbidity and medication use through propensity score matching, we identified 222 024 SSRI users and 221 361 SSRI nonusers. A robust Cox proportional hazards model was used to examine the associations between use of individual SSRIs and the risk of kidney cancer with 1- and 2-year induction periods. The result showed that SSRI users tended to be associated with a lower risk of kidney cancer with a 2-year induction period than nonusers; however, the association was not statistically significant (adjusted hazards ratio [aHR] = 0.88, 95% confidence interval [CI] = 0.77-1.01). We further examined the effects of individual SSRIs and observed a significantly lower risk of kidney cancer associated with the use of citalopram (aHR = 0.67, 95% CI = 0.47-0.96) and paroxetine (aHR = 0.75, 95% CI = 0.58-0.97) with the 2-year induction period. These findings support that SSRIs are associated with decreased kidney cancer risk and indicate that citalopram and paroxetine have protective effects in depressed patients with kidney cancer.

Impact of Polypharmacy for Chronic Ailments in Colon Cancer Patients: A Review Focused on Drug Repurposing

Colorectal cancer is characterized by high incidence worldwide. Despite increased awareness and early diagnosis thanks to screening programmes, mortality remains high, particularly for patients with metastatic involvement. Immune checkpoint inhibitors or poly (ADP-ribose) polymerase (PARP)-inhibitors have met with disappointing results when used in this setting, opposed to other malignancies. New drugs with different mechanisms of action are needed in this disease. Drug repurposing might offer new therapeutic options, as patients with metastatic colorectal cancer often share risk factors for other chronic diseases and thus frequently are on incidental therapy with these drugs. The aim of this review is to summarise the published results of the activity of drugs used to treat chronic medications in patients affected by colorectal cancer. We focused on antihypertensive drugs, Non-Steroid Anti-inflammatory Drugs (NSAIDs), metformin, antidepressants, statins and antibacterial antibiotics. Our review shows that there are promising results with beta blockers, statins and metformin, whereas data concerning antidepressants and antibacterial antibiotics seem to show a potentially harmful effect. It is hoped that further prospective trials that take into account the role of these drugs as anticancer medications are conducted.

Integration of genetic variants and gene network for drug repurposing in colorectal cancer

Even though many genetic risk loci for human diseases have been identified and comprehensively cataloged, strategies to guide clinical research by integrating the extensive results of genetic studies and biological resources are still limited. Moreover, integrative analyses that provide novel insights into disease biology are expected to be especially useful for drug discovery. Herein, we used text mining of genetic studies on colorectal cancer (CRC) and assigned biological annotations to identified risk genes in order to discover novel drug targets and potential drugs for repurposing. Risk genes for CRC were obtained from PubMed text mining, and for each gene, six functional and bioinformatic annotations were analyzed. The annotations include missense mutations, cis-expression quantitative trait loci (cis-eQTL), molecular pathway analyses, protein-protein interactions (PPIs), a genetic overlap with knockout mouse phenotypes, and primary immunodeficiency (PID). We then prioritized the biological risk candidate genes according to a scoring system of the six functional annotations. Each functional annotation was assigned one point, and those genes with a score ≥2 were designated "biological CRC risk genes". Using this method, we revealed 82 biological CRC risk genes, which were mapped to 128 genes in an expanded PPI network. Further utilizing DrugBank and the Therapeutic Target Database, we found 21 genes in our list that are targeted by 166 candidate drugs. Based on data from ClinicalTrials.gov and literature review, we found four known target genes with six drugs for clinical treatment in CRC, and three target genes with nine drugs supported by previous preclinical results in CRC. Additionally, 12 genes are targeted by 32 drugs approved for other indications, which can possibly be repurposed for CRC treatment. Finally, analysis from Connectivity Map (CMap) showed that 18 drugs have a high potential for CRC.

Refocusing the Use of Psychiatric Drugs for Treatment of Gastrointestinal Cancers

Gastrointestinal cancers (GICs) are the most common human tumors worldwide. Treatments have limited effects, and increasing global cancer burden makes it necessary to investigate alternative strategies such as drug repurposing. Interestingly, it has been found that psychiatric drugs (PDs) are promising as a new generation of cancer chemotherapies due to their anti-neoplastic properties. This review compiles the state of the art about how PDs have been redirected for cancer therapeutics in GICs. PDs, especially anti-psychotics, anti-depressants and anti-epileptic drugs, have shown effects on cell viability, cell growth, inhibition of proliferation (cell cycle arrest), apoptosis promotion by caspases activation or cytochrome C release, production of reactive oxygen species (ROS) and nuclear fragmentation over esophageal, gastric, colorectal, liver and pancreatic cancers. Additionally, PDs can inhibit neovascularization, invasion and metastasis in a dose-dependent manner. Moreover, they can induce chemosensibilization to 5-fluorouracil and cisplatin and can act synergistically with anti-neoplastic drugs such as gemcitabine, paclitaxel and oxaliplatin. All anti-cancer activities are given by activation or inhibition of pathways such as HDAC1/PTEN/Akt, EGFR/ErbB2/ErbB3, and PI3K/Akt; PI3K-AK-mTOR, HDAC1/PTEN/Akt; Wnt/β-catenin. Further investigations and clinical trials are needed to elucidate all molecular mechanisms involved on anti-cancer activities as well as adverse effects on patients.

Inverse in silico-in vitro fishing of unexpected paroxetine kinase targets from tumor druggable kinome

The serotonin selective reuptake inhibitor paroxetine has been clinically observed to reposition a significant suppressing potency on human tumors by unexpectedly targeting diverse kinase pathways involved in tumorigenesis. Here, we describe an inverse in silico-in vitro strategy to fish potential kinase targets using the paroxetine as bait. This is different (inverse) to the traditional drug discovery process that commonly screens small-molecule inhibitors for a specific kinase target. In the procedure, cell viability assays demonstrate that paroxetine has strong cytotoxicity on human tumor cell lines. Various protooncogene protein kinases are ontologically/manually enriched to define a druggable kinome, and a systematic interaction profile of paroxetine with the kinome is created, which indicates that paroxetine can potentially bind to some known targets or key regulators of human tumors. Kinase assays determine that paroxetine can effectively inhibit c-Src family kinases at nanomolar or micromolar levels. It is observed that the paroxetine ligand forms a tightly packed interface against the active site of these unexpected kinase targets to constitute several specific hydrogen bonds/π-π/cation-π stackings and a number of nonspecific hydrophobic/vdW contacts, while exposing a portion of molecular surface to solvent. More significantly, the ligand adopts two distinct binding modes (i.e., class I and class II) to interact with different kinases; the class-I mode has a higher stability and inhibitory activity than class-II mode. Steric clash seems to cause the ligand flipping from class I to class II. Graphical abstract.

The Association between Selective Serotonin Reuptake Inhibitors (SSRIs) Use and the Risk of Bladder Cancer: A Nationwide Population-Based Cohort Study

Background: Past studies suggest mixed associations between selective serotonin reuptake inhibitor (SSRI) prescription and carcinogenic risk. There is no epidemiological study reporting on the association between SSRI use and the incidence of bladder cancer. The aim of this study is to determine whether SSRI use influences the risk of bladder cancer. Methods: We conducted a nationwide retrospective cohort study by Taiwan’s National Health Insurance Research Database from January 1, 1997 to December 31, 2013. 192,392 SSRI prescribed individuals were randomly matched 1 to 1 with 191,786 individuals who had never received any SSRIs by propensity scores match. The Cox Proportional Hazard models were conducted to examine the risk of bladder cancer between individuals prescribed SSRIs and individuals not prescribed SSRIs. Results: SSRIs were associated with significant reduced risk of bladder cancer with 0.5, 1, and 2 year induction periods (adjusted hazard ratio (aHR) = 0.86, 95% CI (confidence interval) = 0.76–0.98, aHR = 0.85, 95% CI = 0.75–0.97, and aHR = 0.77, 95% CI = 0.66–0.89). When examining the effect of specific SSRI, there was significantly lower risk of bladder cancer in individuals prescribed fluoxetine (6 month induction period: aHR = 0.78, 95% CI = 0.65–0.93; 1 year induction period: aHR = 0.78, 95% CI = 0.65–0.94; 2 year induction period: aHR = 0.73, 95% CI = 0.60–0.89), paroxetine (6 month induction period: aHR = 0.78, 95% CI = 0.61–0.99; 1 year induction period: aHR = 0.79, 95% CI = 0.61–1.01; 2 year induction period: aHR = 0.72, 95% CI = 0.54–0.95), and citalopram (6 month induction period: aHR = 0.74, 95% CI = 0.53–1.03; 1 year induction period: aHR = 0.70, 95% CI = 0.50–0.99; 2 year induction period: aHR = 0.60, 95% CI = 0.41–0.88). Conclusions: Individuals prescribed fluoxetine, paroxetine, or citalopram had a reduced risk of bladder cancer in this large, cross-national database.

Blockage of Autophagic Flux and Induction of Mitochondria Fragmentation by Paroxetine Hydrochloride in Lung Cancer Cells Promotes Apoptosis via the ROS-MAPK Pathway

Cancer cells are characterized by malignant proliferation and aberrant metabolism and are thereby liable to the depletion of nutrients and accumulation of metabolic waste. To maintain cellular homeostasis, cancer cells are prone to upregulating the canonical autophagy pathway. Here, we identified paroxetine hydrochloride (Paxil) as a late autophagy inhibitor and investigated its killing effect on lung cancer cells and with a xenograft mouse model in vivo. Upregulated LC3-II and p62 expression indicated that Paxil inhibited autophagy. Acid-sensitive dyes (e.g., LysoTracker and AO staining) indicated reduced lysosomal acidity following Paxil treatment; consequently, the maturation of the pH-dependent hydroxylases (e.g., cathepsin B and D) substantially declined. Paxil also induced the fragmentation of mitochondria and further intensified ROS overproduction. Since the autophagy pathway was blocked, ROS rapidly accumulated, which activated JNK and p38 kinase. Such activity promoted the localization of Bax, which led to increased mitochondrial outer membrane permeability. The release of Cytochrome c with the loss of the membrane potential triggered a caspase cascade, ultimately leading to apoptosis. In contrast, the clearance of ROS by its scavenger, NAC, rescued Paxil-induced apoptosis accompanied by reduced p38 and JNK activation. Thus, Paxil blocked the autophagic flux and induced the mitochondria-dependent apoptosis via the ROS-MAPK pathway.

N-Methylparoxetine Blocked Autophagic Flux and Induced Apoptosis by Activating ROS-MAPK Pathway in Non-Small Cell Lung Cancer Cells

The main mechanistic function of most chemotherapeutic drugs is mediated by inducing mitochondria-dependent apoptosis. Tumor cells usually respond to upregulate autophagy to eliminate impaired mitochondria for survival. Hypothetically, inhibiting autophagy might promote mitochondria-dependent apoptosis, thus enhancing the efficacy of chemotherapeutic therapies. We previously identified N-methylparoxetine (NMP) as an inducer of mitochondrial fragmentation with subsequent apoptosis in non-small cell lung cancer (NSCLC) cells. We discovered that ROS was accumulated in NMP-treated NSCLC cells, followed by c-Jun N-terminal kinase (JNK) and p38 MAP kinase (p38) activation. This was reversed by the application of a reactive oxygen species (ROS) scavenger, N-acetylcysteine (NAC), leading to a reduction in apoptosis. Our data suggested that NMP induced apoptosis in NSCLC cells by activating mitogen-activated protein kinase (MAPK) pathway. We further speculated that the remarkable increase of ROS in NMP-treated NSCLC cells might result from an inhibition of autophagy. Our current data confirmed that NMP blocked autophagy flux at late stage wherein lysosomal acidification was inhibited. Taken together, this study demonstrated that NMP could exert dual apoptotic functions—mitochondria impairment and, concomitantly, autophagy inhibition. NMP-related excessive ROS accumulation induced apoptosis by activating the MAPK pathway in NSCLC cells.

Anticancer activity of paroxetine in human colon cancer cells: Involvement of MET and ERBB3

The concept of drug repositioning has recently received considerable attention in the field of oncology. In the present study, we propose that paroxetine can be used as a potent anticancer drug. Paroxetine, one of the selective serotonin reuptake inhibitors (SSRIs), has been widely prescribed for the treatment of depression and anxiety disorders. Recently, SSRIs have been reported to have anticancer activity in various types of cancer cells; however, the underlying mechanisms of their action are not yet known. In this study, we investigated the potential anticancer effect of paroxetine in human colorectal cancer cells, HCT116 and HT‐29. Treatment with paroxetine reduced cell viability, which was associated with marked increase in apoptosis, in both the cell lines. Also, paroxetine effectively inhibited colony formation and 3D spheroid formation. We speculated that the mode of action of paroxetine might be through the inhibition of two major receptor tyrosine kinases – MET and ERBB3 – leading to the suppression of AKT, ERK and p38 activation and induction of JNK and caspase‐3 pathways. Moreover, in vivo experiments revealed that treatment of athymic nude mice bearing HT‐29 cells with paroxetine remarkably suppressed tumour growth. In conclusion, paroxetine is a potential therapeutic option for patients with colorectal cancer.