Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 23, Issue 15, 2023

Cardiotoxicity represents an important acute or chronic adverse event of treatment modalities for childhood cancer. In the last two decades the emergence of novel cancer therapies has aimed to increase unaided or mostly in combination with conventional chemotherapy for the survival rates of pediatric cancer especially for those patients with relapsed and/or refractory disease. The use of emerging targeted therapies in combination with conventional chemotherapy is related to cardiovascular adverse events mostly reported in adults. The aim of our short review was to investigate the cardiotoxic side effects of targeted chemotherapeutic agents as monoclonal antibodies and small molecules in pediatric cancer patients.

Background: Molecules secreted by Trypanosoma cruzi (T. cruzi) have beneficial effects on the immune system and can fight against cancer by inhibiting the growth of tumor cells, preventing angiogenesis, and promoting immune activation. Objective: This study aimed to investigate the effects of molecules secreted by Trypanosoma cruzi on the growth of colon and breast cancer cells, to understand the underlying mechanisms of action. Results: Calreticulin from T. cruzi, a 45 kDa protein, participates in essential changes in the tumor microenvironment by triggering an adaptive immune response, exerting an antiangiogenic effect, and inhibiting cell growth. On the other hand, a 21 kDa protein (P21) secreted at all stages of the parasite's life cycle can inhibit cell invasion and migration. Mucins, such as Tn, sialyl-Tn, and TF, are present both in tumor cells and on the surface of T. cruzi and are characterized as common antigenic determinants, inducing a cross-immune response. In addition, molecules secreted by the parasite are used recombinantly in immunotherapy against cancer for their ability to generate a reliable and long-lasting immune response. Conclusion: By elucidating the antitumor mechanisms of the molecules secreted by T. cruzi, this study provides valuable insights for developing novel therapeutic strategies to combat colon and breast cancer.

Introduction: Prostate cancer is the second most prevalent cancer among men. Despite different treatments, including surgery, chemotherapy, radiation therapy, hormone therapy and immunotherapy for this disease, patients ultimately progress to advanced states. Thus, there is a need for new treatment options targeting cell growth and apoptosis to better control the proliferation and metastasis of these cells. There are many reports indicating overexpression of the 15-lipoxygenase-1 (15-LOX-1) enzyme in prostate tumors. Studies have also shown that inhibition of this enzyme prevents the progression of prostate cancer. Objective: This study was conducted to assess the anti-cancer properties of some coumarin derivatives as possible 15- LOX-1 inhibitors, on PC-3 prostate cancer cells. Methods: In this study, the activity of 15-LOX-1 was evaluated in PC-3 cells by a spectrophotometric assay. In addition, due to high similarity between the 15-LOX-1 and soybean 15-lipoxygenase (SLO) (L1; EC 1, 13, 11, 12) active sites, the soybean SLO was used to investigate inhibitory effects of synthetic coumarin compounds 8- isopentenyloxycoumarin (8-IC), 8-isopentenyloxy-3-carboxycoumarin (8-ICC), 8-geranyloxycoumarin (8-GC), 8- geranyloxy-3-carboxycoumarin (8-GCC), and 8-farnesyloxy-3-carboxycoumarin (8-FCC) on this enzyme. Moreover, the cytotoxic and anticancer effects of the coumarin compounds were examined on PC-3 (Prostate Cancer) and HDF-1 (Human Dermal Fibroblast) cells by alamarBlue assay. Finally, apoptosis-inducing effects of all synthetic compounds were determined by flow cytometry. Results: The IC50 values obtained by the alamarBlue test revealed that 8-IC, 8-GC and 8-GCC had cytotoxic effects on PC-3 cells. Treating both PC-3 and HDF-1 cells with 8-ICC and 8-FCC did not significantly reduce cell number. Furthermore, the IC50 values of 8-IC on HDF-1 cells showed cytotoxic effects, while treating these cells with 8-GC and 8- GCC did not show any significant cytotoxicity on these normal human fibroblasts. Assessing the ability of 4-MMPB (as a specific inhibitor of 15-LOX-1), 8-GC, and 8-GCC compounds to inhibit SLO revealed that these compounds exerted strong 15-LOX-1 inhibitory activity, while 8-IC and 8-FCC had a weak inhibitory effect and also 8-ICC showed no inhibitory effect on SLO enzyme. In addition, flow cytometric analysis by FITC (fluorescein isothiocyanate)- annexin V and propidium iodide showed that treatment with IC50 values of 8-GC and 8-GCC induced apoptosis in 35.2% and 30.8% of PC-3 cells, respectively. Conclusion: Thus, 8-GC and 8-GCC can be introduced as effective anticancer agents with apoptosis-inducing properties. Furthermore, our results suggest that the cytotoxic effects of these compounds might be related to the inhibition of 15-LOX-1 enzyme in PC-3 cells. On the other hand, the cytotoxic effects of 8-IC might be due to the inhibition of other signaling pathways in PC-3 cells. However, further in vivo experiments are required to determine the exact mechanisms involved in the anticancer effects of these coumarin compounds.

Background: 20(R)-PD, a tetracyclic triterpenoid, is a non-natural saponin present in the form of protopanaxadiol. Because of its essential biological activities, especially anti-tumor activity, structural modification of 20(R)-PD and the development of innovative and novel 20(R)-PD derivatives with better anti-tumor activity are increasingly relevant. Aims: 20(R)-Panaxadiol (20(R)-PD) can inhibit tumor proliferation. Three series of novel 20(R-PD derivatives were synthesized by modifying the A-ring. Objective: The objective of this work was to synthesize and evaluate the in vitro anti-proliferative activities of 20(R)- PD derivatives in LNCaP, LS180, and MKN45 cancer cells. Structural modifications were performed at the C-3 position and A-ring. Methods: The in vitro anti-proliferative activities of novel derivatives in LNCaP, LS180, and MKN45 cells were evaluated by the MTT assay. The effects of compounds 5 and C9 on apoptosis were determined by flow cytometry. Results: Compounds 5, B2, C2, C4, C7, C8, C9, C10, and C11 exhibited good anti-proliferative activities in LNCaP, LS180, and MKN45 cells in vitro. The best anti-proliferative activity was observed for the C-series derivatives with the introduction of amino acids at the C-3 position. C9 exhibited good potent activity with an IC50 of 2.89 μM. Conclusion: Compound C9 is a potential candidate with potent anti-proliferative activity.

Introduction: Several mechanisms are known for the anticancer effects of cisplatin. However, its most wellknown function involves binding to DNA and activating the DNA damage response. Methods: Despite its good effects, the treatment process often leads to chemoresistance and affects the mechanisms that support cell survival, such as pathways that promote cell growth, apoptosis, DNA damage repair, and endocytosis. For this reason, we investigated the effects of a new metal complex (tetradentate Schiff base zinc(II) complex) on breast cancer cells (T-47D). We evaluated its effect on cytotoxicity, apoptosis, and drug resistance in comparison to cisplatin. Results: The results of the MTT test showed that tetradentate Schiff base zinc(II) complex has good cytotoxicity compared to cisplatin. The IC50 values for the [Zn(SB)]Cl2 complex and cisplatin after 72 h of exposure were equal to 42.1 and 276.1 μM, respectively. Real-time PCR assay confirmed that the [Zn(SB)]Cl2 complex activated the mitochondrial pathway of apoptosis and increased the expression of Bak1 and caspase-3 genes significantly compared to cisplatin. More importantly, the [Zn(SB)]Cl2 was able to reduce the expression of the β-catenin gene, which plays a role in drug resistance, by 0.011 compared to the control. Conclusion: Therefore, we can hope for this new complex because, without the help of any β-catenin silencing agent, it was able to inhibit the drug resistance in the T-47D cell line that overexpresses the β-catenin gene.

Background: Cancer is a life-threatening condition with an economic burden on societies. Phytotherapy is rapidly taking place in cancer research to increase the success of treatment and quality of life. Thymoquinone (TQ) is the main active phenolic compound obtained from the essential oil of the Nigella sativa (black cumin) plant seed. For a long time, black cumin has been used traditionally for the remedy of different diseases because of its various biological effects. It has been shown that most of these effects of black cumin seeds are due to TQ. TQ became a popular research topic for phytotherapy studies for its potential therapeutic applications, and more research is going on to fully understand its mechanisms of action, safety, and efficacy in humans. KRAS is a gene that regulates cell division and growth. Monoallelic variants in KRAS result in uncontrollable cell division, leading to cancer development. Studies have shown that cancer cells with KRAS mutations are often resistant to certain types of chemotherapy and targeted therapies. Objective: This study aimed to compare the effect of TQ on cancer cells with and without KRAS mutation to better understand the reason why TQ may have different anticancer effects in the different types of cancer cells. Methods: TQ was investigated for its cytotoxic and apoptotic effects in laryngeal cancer cells (HEp-2) without KRAS mutation and compared to mutant KRAS-transfected larynx cancer cells and KRAS mutation-carrying lung cancer cells (A549). Results: We showed that TQ has more cytotoxic and apoptotic effects on laryngeal cancer cells without KRAS mutation than in cells with mutation. Conclusion: KRAS mutations decrease the effect of TQ on cell viability and apoptosis, and further studies are needed to fully understand the relationship between KRAS mutations and thymoquinone effectiveness in cancer treatment.

Introduction: Among gynecological cancers, ovarian cancer has a high mortality rate. Cisplatin-based chemotherapy is commonly used for the treatment of ovarian cancer. However, the clinical efficacy of cisplatin in ovarian cancer is limited due to the development of chemo-resistance during treatment. Objective: In the study, we aimed to investigate the synergistic anti-cancer activity and targets of the FDA-approved drug disulfiram combined with cisplatin in ovarian cancer. Methods: The cell viability was determined by Celltier-Glo luminescent assay. The synergistic anti-cancer activity was assessed by combination index. Cell cycle and apoptosis were detected by flow cytometry. The in vivo anti-tumor activity and side effects were evaluated using a xenografted mice model. The synergistic anti-cancer targets were identified by a mass spectrometry-based proteomics analysis. Results: In this study, we first found that disulfiram synergistically enhanced the anti-tumor activity of cisplatin in chemo-resistant ovarian cancer cells, which was accompanied by the enhanced induction of cellular apoptosis. Secondly, the in vivo study demonstrated that the combination treatment of disulfiram and cisplatin dramatically inhibited tumor growth and had no apparent side effects in ovarian cancer xenografted mice. Finally, proteomics analysis identified SMAD3 as a potential target of disulfiram-cisplatin combined treatment, and the down-regulation of SMAD3 could increase cisplatin-induced cell death in ovarian cancer. Conclusion: Combination treatment of disulfiram and cisplatin synergistically inhibited the growth of ovarian cancer through down-regulating SMAD3. As a repurposed drug, disulfiram could be quickly transformed into a clinic to overcome cisplatin resistance for the treatment of ovarian cancer.

Background: Melanoma is of great interest due to its aggressive behavior and less favorable prognosis. The need for the development of novel drugs for the treatment of melanoma is urgent. Considerable evidence indicated that Schisandrin B (Sch B), a bioactive compound extracted from Schisandra chinensis, has numerous anti-tumor properties in multiple malignant tumors. A few studies have reported the effect of Sch B on melanogenesis in the melanoma B16F10 cell line; however, the specific anti-tumor effects and mechanisms need to be further explored. Objective: This study aimed to investigate the effects of Sch B on the cell viability, migration, invasion, and cell cycleblocking of melanoma cells and explore its potential anti-tumor mechanism in vitro and in vivo. Methods: Melanoma cells (A375 and B16) were treated with different concentrations of Sch B (0, 20, 40, 60, or 80 μM), with dimethyl sulfoxide (DMSO) as control. The inhibitory effect of Sch B on A375 and B16 melanoma cells was verified by crystal violet assay and CCK8 assay. The flow cytometry was performed to observe cell cycle blocking. The effect of Sch B on the migration and invasion of melanoma cells was detected by wound healing assay and transwell assay, respectively. Western blot analysis was used to determine protein expression levels. The growth of the A375 melanoma xenograft-treated groups and immunohistochemical staining were conducted to assess the anti-tumor effect of Sch B in vivo. Results: The crystal violet assay and CCK8 assay showed that Sch B significantly inhibited melanoma cell viability in a dose-dependent manner. Meanwhile, the flow cytometry analysis revealed that Sch B induced melanoma cell cycleblocking at the G1/S phase. In addition, the wound healing assay and transwell assay showed that Sch B inhibited the migration and invasion of melanoma cells. Furthermore, by establishing an animal model, we found that Sch B significantly inhibited the growth of melanoma in vivo. The potential mechanism could be that Sch B inhibited the activity of the Wnt/β-catenin signaling pathway. Conclusion: These findings indicated that Sch B inhibits the cell viability and malignant progression of melanoma cells via the Wnt/β-catenin pathway and induces cell cycle arrest. Our study suggests that Sch B has potential as a bioactive compound for the development of new drugs for melanoma.

Background: Chelidonine is a potent anticancer against several cell lines. However, low bioavailability and water solubility restrict the clinical applications of this compound. Objective: The aim of this research was to develop a novel formulation of chelidonine encapsulated in the nanoparticles of poly(d l-lactic-co-glycolic acid) (PLGA) employing vitamin E D-α-tocopherol acid polyethylene glycol 1000 succinate (E TPGS) as a modifier to increase bioavailability. Methods: Chelidonine-encapsulated PLGA nanoparticles were fabricated using a single emulsion method and modified by various concentrations of E TPGS. Nanoparticles were recognized in terms of morphology, surface charge, drug release, size, drug loading, and encapsulation efficiency to obtain the optimized formulation. The cytotoxicity of different nanoformulations in HT-29 cells was evaluated using the MTT assay. The cells were stained with propidium iodide and annexin V solution to evaluate apoptosis using flow cytometry. Results: Spherical nanoparticles prepared with 2% (w/v) of E TPGS had the optimum formulation in the nanometer size range (153 ± 12.3 nm), with a surface charge of -14.06 ± 2.21 mV, encapsulation efficiency of 95.58 ± 3.47%, drug loading of 33.13 ± 0.19%, and drug release profile of 73.54 ± 2.33. In comparison with non-modified nanoparticles and free chelidonine, E TPGS-modified nanoformulations improved anti-cancer capability even after three-months storage. Conclusion: Our results showed that E TPGS is an effective biomaterial for surface modification of nanoparticles, which can serve as a potential treatment for cancer.

Introduction: Breast cancer is the most frequent malignancy in women with more than one in ten new cancer diagnoses each year. Synthetic products are a key source for the identification of new anticancer medicines and drug leads. Objectives: Imidazopyrazine is a highly favored skeleton for the design of new anticancer drugs. In silico designed derivatives were screened using computer aided drug design techniques and validated using MTT assay. Methods: A template-based methodology was used in the current work to create novel Imidazopyrazine derivatives, targeting the NPY1R protein. Molecular docking, Diffusion docking, MD simulation, MM-GBSA and meta-dynamics techniques were followed. MTT assay was performed to validate the activity of principal compound. Results: A docking score of -6.660 and MMGBSA value of -108.008 (+/-) 9.14 kcal/mol was obtained from the investigations conducted. In addition, molecular dynamics simulation was carried out for 500 ns, yielding a stable RMSD and value of 5.6 Å, thus providing insights on the stability of the protein conformation on interaction with the principal compound. Furthermore, the in vivo validation studies conducted via MTT assay showed an IC50 value of 73.45 (+/-) 0.45 μg /mL. Conclusion: The research has produced encouraging findings and can be applied as a model for precise enumerations in the future. It also encourages the study of novel synthetic compounds with potential anti-cancer properties.