3-O-(E)-p-Coumaroyl betulinic acid possess anticancer activity and inhibit Notch signaling pathway in breast cancer cells and mammosphere

Therapeutic vulnerabilities in triple negative breast cancer: Stem-like traits explored within molecular classification

Triple Negative Breast Cancer (TNBC) is the most aggressive type of breast cancer (BC). Despite advances in the clinical management of TNBC, recurrence-related mortality remains a challenge. The stem-like phenotype of TNBC plays a significant role in the persistence of minimal disease residue after therapy. Individuals exhibiting stem-like characteristics are particularly prone to inducing malignant relapse accompanied by strong resistance. Therefore, stem-like traits have been broadly proposed as therapeutic vulnerabilities to treat TNBC and reduce recurrence. However, heterogeneity within TNBC often generally restricts the stability of the therapeutic efficacy. To understand the heterogeneity and manage TNBC more precisely, multiple TNBC subtyping categories have been reported, providing the basis for profile-according therapeutic regimens. To provide more insight into targeting stem-like traits to ablate TNBC and reduce recurrence in the context of heterogeneity, this paper reviewed the molecular subtyping of TNBC, identified the consensus subtypes with distinct stem-like phenotypes, characterized the stemness hierarchy of TNBC, outlined the biological models for stem-like TNBC subtypes, summarized the therapeutic vulnerabilities in stem-like traits of the subtypes, and proposed potential therapeutic regimens targeting stem-like characteristics to improve TNBC prognosis.

Breast cancer drug resistance: Decoding the roles of Hippo pathway crosstalk

The most significant factors that lead to cancer-related death in breast cancer (BC) patients include drug resistance, migration, invasion, and metastasis. Several signaling pathways are involved in the development of BC. The different types of BC are initially sensitive to chemotherapy, and drug resistance can occur through multiple molecular mechanisms. Regardless of developing targeted Therapy, due to the heterogenic nature and complexity of drug resistance, it is a major clinical challenge with the low survival rate in BC patients. The deregulation of several signaling pathways, particularly the Hippo pathway (HP), is one of the most recent findings about the molecular mechanisms of drug resistance in BC, which are summarized in this review. Given that HP is one of the recent cancer research hotspots, this review focuses on its implication in BC drug resistance. Unraveling the different molecular basis of HP through its crosstalk with other signaling pathways, and determining the effectiveness of HP inhibitors can provide new insights into possible therapeutic strategies for overcoming chemoresistance in BC.

Unveiling the pharmacological potential of plant triterpenoids in breast cancer management: an updated review

Breast cancer is the most prevalent type of cancer, the fifth leading cause of cancer-related deaths, and the second leading cause of cancer deaths among women globally. Recent research has provided increasing support for the significance of phytochemicals, both dietary and non-dietary, particularly triterpenoids, in the mitigation and management of breast cancer. Recent studies showed that triterpenoids are promising agents in the treatment and inhibition of breast cancer achieved through the implementation of several molecular modes of action on breast cancer cells. This review discusses recent innovations in plant triterpenoids and their underlying mechanisms of action in combating breast cancer within the timeframe spanning from 2017 to 2023. The present work is an overview of different plant triterpenoids with significant inhibition on proliferation, migration, apoptosis resistance, tumor angiogenesis, or metastasis in various breast cancer cells. The anticancer impact of triterpenoids may be attributed to their antiproliferative activity interfering with angiogenesis and differentiation, regulation of apoptosis, DNA polymerase inhibition, change in signal transductions, and impeding metastasis. The present review focuses on several targets, mechanisms, and pathways associated with pentacyclic triterpenoids, which are responsible for their anticancer effects. We could conclude that natural triterpenoids are considered promising agents to conquer breast cancer.

Cytotoxicity of dioncophylline A and related naphthylisoquinolines in leukemia cells, mediated by NF-κB inhibition, angiogenesis suppression, G2/M cell cycle arrest, and autophagy induction

BACKGROUND

Inhibition of NF-κB activity represents a strategy to treat acute myeloid leukemia, one of the most lethal leukemia types. Naphthylisoquinolines (NIQs) are cytotoxic alkaloids from lianas of the families Ancistrocladaceae and Dioncophyllaceae, which are indigenous to tropical rainforests.

PURPOSE

Uncovering therapeutic possibilities and underlying molecular mechanisms of dioncophylline A and its derivatives towards NF-κB related cellular processes.

METHODS

Resazurin-based cell viability assay was performed for dioncophylline A and three derivatives on wild-type CCRF-CEM and multidrug-resistant CEM/ADR5000 cells. Transcriptome analysis was executed to discover cellular functions and molecular networks associated with dioncophylline A treatment. Expression changes obtained by mRNA microarray hybridization were confirmed using qRT-PCR. Molecular docking was applied to predict the affinity of the NIQs with NF-κB. To validate the in silico approach, NF-κB reporter assays were conducted on HEK-Blue™ Null1 cells. Cell death mechanisms and cell cycle arrest were studied using flow cytometry. The potential activity on angiogenesis was evaluated with the endothelial cell tube formation assay on HUVECs using fluorescence microscopy. Intracellular NF-κB location in HEK-Blue™ Null1 cells was visualized with immunofluorescence. Finally, the anti-tumor activity of dioncophylline A was studied by a xenograft zebrafish model in vivo.

RESULTS

Our study demonstrated that dioncophylline A and its derivatives exerted potent cytotoxicity on leukemia cells. Using Ingenuity Pathway Analysis, we identified the NF-κB network as the top network, and docking experiments predicted dioncophylline A and two of its derivatives sharing the same binding pocket with the positive control compound, triptolide. Dioncophylline A showed the best inhibitory activity in NF-κB reporter assays compared to its derivatives, caused autophagy rather than apoptosis, and induced G2/M arrest. It also prevented NF-κB translocation from the cytoplasm to the nucleus. Tube formation as an angiogenesis marker was significantly suppressed by dioncophylline A treatment. Finally, the remarkable anti-tumor activity of dioncophylline A was proven in zebrafish in vivo.

CONCLUSION

Taken together, we report for the first time the molecular mechanism behind the cytotoxic effect of dioncophylline A on leukemia cells. Dioncophylline A showed strong cytotoxic activity, inhibited NF-κB translocation, significantly affected the NF-κB in silico and in vitro, subdued tube formation, induced autophagy, and exerted antitumor activity in vivo. Our findings enlighten both the cellular functions including the NF-κB signaling pathway and the cytotoxic mechanism affected by dioncophylline A.

Study of the PI3K/Akt/mTOR signaling pathway in vitro and molecular docking analysis of periplocin inhibits cell cycle progression and induces apoptosis in MDA-MB-231

Breast cancer mainly affects women and is the second leading cause of cancer-related deaths worldwide. Breast cancer affects women aged 15-59. The current study explored periplocin's anticancer activities against breast cancer MDA-MB-231 cells by down-regulating the PI3K/Akt/mTOR pathway. The MTT assay assessed control-treated and periplocin (2.5-50 μM) treated MDA-MB-231 cell viability. ROS accumulation and apoptosis levels in periplocin-treated cells were examined using DAPI, dual staining, and Annexin V-FITC/PI assays. Caspase enzymes were studied using assay kits. Flow cytometry was used to measure cell cycle distributions. Periplocin-treated cells were analyzed using RT-PCR assays and insilico analyses for the expression of PI3K/Akt/mTOR molecules. The periplocin treatment remarkably reduced the viability of the MDA-MB-231 cells, with an IC50 concentration of 7.5 μM. The fluorescent staining assays revealed a substantial increase in ROS levels and apoptotic events in the periplocin-treated cells. The flow cytometry analysis revealed that periplocin triggered apoptosis and arrested the cell cycle in G0/G1 phases. Periplocin increased the caspase-3, -8, and -9 enzyme activities. In MDA-MB-231 cells, Periplocin decreased PI3K/Akt/mTOR activity, and in silico analysis, Periplocin was inhibited by CDK8-Cyclin C interactions. Periplocin has anticancer properties against breast cancer and may be an effective therapeutic agent for treating breast cancer.

Piper chaba, an Indian spice plant extract, inhibits cell cycle G1/S phase transition and induces intrinsic apoptotic pathway in luminal breast cancer cells

Piper chaba (Piperaceae) is a medicinal spice plant that possesses several pharmacological activities. In the present study, we for the first time studied the effect of P. chaba extract on breast cancer cells. P. chaba stem methanolic (PCSM) extract produced time and dose dependent cytotoxicity in luminal breast cancer cells (MCF-7 and T47D) with a minimal toxicity in breast normal cells (MCF-10A) at 10-100 µg/mL concentration. PCSM extract exerts 16.79 and 31.21 µg/mL IC50 for T47D and MCF-7 cells, respectively, in 48 h treatment. PCSM significantly arrests the T47D cells at the G0/G1 phase by reducing the CCND1 and CDK4 expression at mRNA and protein levels. PCSM extract treatment significantly altered nuclear morphology, mitochondria membrane potential, and production of reactive oxygen species in T47D cells at IC50 concentration. Extract treatment significantly altered the Bax/Bcl-2 ratio and altered caspase 8 and 3 mRNA/protein levels in T47D cells. Confocal microscopy showed an increase in late apoptosis in PCSM extract-treated breast cancer cells at IC50 . Further, an increased caspase 9 and caspase 3/7 enzymatic activity was observed in test cells compared with nontreated cells. In conclusion, P. chaba phytocompound possesses the potential to induce cell cycle arrest and induce apoptosis in luminal breast cancer cells.

Hesperidin potentially interacts with the catalytic site of gamma-secretase and modifies notch sensitive genes and cancer stemness marker expression in colon cancer cells and colonosphere

Gamma secretase (GS) produces Notch Intracellular Domain (NICD) by trans-membrane cleavage of notch receptor. The NICD enters the nucleus and activates the notch signaling pathway (NSP) by activating notch-responsive gene transcription. Hyperactivation of NSP is related to cancer aggressiveness, therapy resistance, and poor therapy outcome, and decreased overall disease-free survival in patients. Till date, none of the GS inhibitors (GSI) has been clinically approved due to their toxicity in patients. Thus in the present study, we explored the GS catalytic site binding potential of hesperidin (natural flavone glycoside) and its effect on notch responsive gene expression in HCT-116 cells. Molecular docking, MM-GBSA binding energy calculations, and molecular dynamics (MD) simulation experiments were performed to study the GS catalytic site binding potential of hesperidin. The compound showed better GS catalytic site binding potential at the active site compared to experimentally validated GSI, N-N-(3, 5-Difluorophenacetyl)-L-alanyl-S-phenylglycine t-butyl ester (DAPT) in molecular docking and MM-GBSA experiments. MD simulation results showed that hesperidin forms stable and energetically favorable complex with gamma secretase in comparison to standard inhibitor (DAPT)-GS complex. Further, in vitro experiments showed that hesperidin inhibited cell growth and sphere formation potential in HCT-116 cells. Further, hesperidin treatment altered notch responsive genes (Hes1, Hey1, and E-cad) and cancer stemness/self-renewal markers expression at transcription levels. In conclusion, hesperidin produces toxicity in HCT-116 cells and decreases colonosphere formation by inhibiting transcription of notch signaling pathway target genes and stemness markers.Communicated by Ramaswamy H. Sarma.

Betulinic acid in the treatment of breast cancer: Application and mechanism progress

Betulinic acid (BA) is a pentacyclic triterpene compound, which can be obtained by separation, chemical synthesis and biotransformation. BA has excellent biological activities, especially its role in the treatment of breast cancer deserves attention. Its mechanisms mainly include inducing mitochondrial oxidative stress, regulating specific protein (Sp) transcription factors, inhibiting breast cancer metastasis, inhibiting glucose metabolism and NF-κB pathway. In addition, BA can also increase the sensitivity of breast cancer cells to other chemotherapy drugs such as paclitaxel and reduce its toxic side effects. This article reviews the application and possible mechanism of BA in the treatment of breast cancer.

Review deciphering potent therapeutic approaches targeting Notch signaling pathway in breast cancer

In the current period of drug development, natural products have provided an unrivaled supply of anticancer medications. By modifying the cancer microenvironment and various signaling pathways, natural products and their derivatives and analogs play a significant role in cancer treatment. These substances are effective against several signaling pathways, particularly the cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch, Wnt, and Hedgehog pathways). Natural products have a long history, but more research is needed to understand their current function in the research and development of cancer treatments and the potential for natural products to serve as a significant source of therapeutic agents in the future. Several target-specific anticancer medications failed to treat cancer, necessitating research into natural compounds with multiple target properties. To help develop a better treatment plan for managing breast cancer, this review has outlined the anticancerous potential of several therapeutic approaches targeting the notch signaling system in breast tumors.

Anti-proliferative, apoptosis inducing, and antioxidant potential of Callistemon lanceolatus bark extracts: an in vitro and in silico study

The present study reports anticancer and antioxidant activities of Callistemon lanceolatus bark extracts. Anticancer activity was studied against MDA-MB-231 cells. Antioxidant assessment of the chloroform and methanol extracts showed considerable free radical scavenging, metal ion chelating, and reducing power potential. Chloroform extract exhibited potent inhibition of cancer cell proliferation in MTT assay (IC₅₀ 9.6 μg/ml) and promoted programmed cell death. Reactive oxygen species (ROS) generation, mitochondria membrane potential (MMP) disruption ability, and nuclear morphology changes were studied using H₂-DCFDA, JC-1, and Hoechst dyes, respectively, using confocal microscopy. Apoptotic cells exhibited fragmented nuclei, increased ROS generation, and altered MMP in dose- and time-dependent manner. Chloroform extract upregulated the BAX-1 and CASP3 mRNA expression coupled with downregulation of BCL-2 gene. Further, in silico docking of phytochemicals present in C. lanceolatus with anti-apoptotic Bcl-2 protein endorsed apoptosis by its inhibition and thus corroborated the experimental findings. Obatoclax, a known inhibitor of Bcl-2 was used as a reference compounds.

Identification of miRNAs and related hub genes associated with the triple negative breast cancer using integrated bioinformatics analysis and in vitro approach

Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype generally associated with younger women. Due to the lack of suitable drugable targets in TNBC, the microRNAs are considered as a better hope as therapeutic agents for the management of the disease. In this study, we identified differentially expressed miRNAs (DEMs) and associated hub genes in TNBC microarray data (GSE38167, GSE60714, and GSE10833) using bioinformatics tools. The identified miRNAs and genes were validated in the TNBC cell line model (MDA-MB-231) compared with the normal breast cells (MCF-10A) using the qRT-PCR technique. False-positive DEMs were avoided by comparing the DEMs profile of TNBC and triple positive breast cancer (TPBC) cell line model (BT474) compared with the MCF-10A cells data. In addition, we studied the effect of anticancer phytochemicals on the differential expression of miRNAs and genes in MDA-MB-231 cells. Furthermore, target predictions, functional enrichment and KEGG pathway analysis, mutation and copy number alterations, and overall survival analysis of DEMs in TNBC sample was investigated using standard computational tools. The study identifies first time the association of hsa-miR-1250, has-miR-1273, and has-miR-635 with the TNBC. DEMs showed significant association with the Wnt, ErbB, PI3-Akt and cAMP signaling pathways having clinical implications in TNBC tumorigenesis. The DEMs and hub genes (HOXC6 and ACVR2B) showed survival disadvantages in TNBC patients. In summary, the identified miRNAs and hub genes show important implications in TNBC tumorigenesis and patient survival. We recommend further experimental studies on pathophysiological mechanism of the identified miRNAs and hub genes in TNBC.Communicated by Ramaswamy H. Sarma.

Naphthylisoindolinone alkaloids: the first ring-contracted naphthylisoquinolines, from the tropical liana Ancistrocladus abbreviatus, with cytotoxic activity

The West African liana Ancistrocladus abbreviatus is a rich source of structurally most diverse naphthylisoquinoline alkaloids. From its roots, a series of four novel representatives, named ancistrobrevolines A-D (14-17) have now been isolated, displaying an unprecedented heterocyclic ring system, where the usual isoquinoline entity is replaced by a ring-contracted isoindolinone part. Their constitutions were elucidated by 1D and 2D NMR and HR-ESI-MS. The absolute configurations at the chiral axis and at the stereogenic center were assigned by using experimental and computational electronic circular dichroism (ECD) investigations and a ruthenium-mediated oxidative degradation, respectively. For the biosynthetic origin of the isoindolinones from 'normal' naphthyltetrahydroisoquinolines, a hypothetic pathway is presented. It involves oxidative decarboxylation steps leading to a ring contraction by a benzilic acid rearrangement. Ancistrobrevolines A (14) and B (15) were found to display moderate cytotoxic effects (up to 72%) against MCF-7 breast and A549 lung cancer cells and to reduce the formation of spheroids (mammospheres) in the breast cancer cell line.

The Notch Signaling Pathway Contributes to Angiogenesis and Tumor Immunity in Breast Cancer

Breast cancer in women is the first leading tumor in terms of incidence worldwide. Some subtypes of BC lack distinct molecular targets and exhibit therapeutic resistance; these patients have a poor prognosis. Thus, the search for new molecular targets is an ongoing challenge for BC therapy. The Notch signaling pathway is found in both vertebrates and invertebrates, and it is a highly conserved in the evolution of the species, controlling cellular fates such as death, proliferation, and differentiation. Numerous studies have shown that improper activation of Notch signaling may lead to excessive cell proliferation and cancer, with tumor-promoting and tumor-suppressive effects in various carcinomas. Thus, inhibitors of Notch signaling are actively being investigated for the treatment of various tumors. The role of Notch signaling in BC has been widely studied in recent years. There is a growing body of evidence suggesting that Notch signaling has a pro-oncogenic role in BC, and the tumor-promoting effect is largely a result of the diverse nature of tumor immunity. Immunological abnormality is also a factor involved in the pathogenesis of BC, suggesting that Notch signaling could be a target for BC immunotherapies. Furthermore, angiogenesis is essential for BC growth and metastasis, and the Notch signaling pathway has been implicated in angiogenesis, so studying the role of Notch signaling in BC angiogenesis will provide new prospects for the treatment of BC. We summarize the potential roles of the current Notch signaling pathway and its inhibitors in BC angiogenesis and the immune response in this review and describe the pharmacological targets of Notch signaling in BC, which may serve as a theoretical foundation for future research into exploring this pathway for novel BC therapies.

Withaniasomnifera phytochemicals possess SARS-CoV-2 RdRp and human TMPRSS2 protein binding potential

Abstract

Coronavirus disease-19 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has infected approximately 26 million people and caused more than 6 million deaths globally. Spike (S)-protein on the outer surface of the virus uses human trans-membrane serine protease-2 (TMPRSS2) to gain entry into the cell. Recent reports indicate that human dipeptidyl peptidase-4 inhibitors (DPP4 or CD26) could also be utilized to check the S-protein mediated viral entry into COVID-19 patients. RNA dependent RNA polymerase (RdRp) is another key virulence protein of SARS-CoV-2 life cycle. The study aimed to identify the potential anti-SARS-CoV-2 inhibitors present in Withania somnifera (Solanaceae) using computer aided drug discovery approach. Molecular docking results showed that flavone glycoside, sugar alcohol, and flavonoid present in W. somnifera showed - 11.69, - 11.61, - 10.1, - 7.71 kcal/mole binding potential against S-protein, CD26, RdRp, and TMPRSS2 proteins. The major standard inhibitors of the targeted proteins (Sitagliptin, VE607, Camostat mesylate, and Remdesivir) showed the - 7.181, - 6.6, - 5.146, and - 7.56 kcal/mole binding potential. Furthermore, the lead phytochemicals and standard inhibitors bound and non-bound RdRp and TMPRSS2 proteins were subjected to molecular dynamics (MD) simulation to study the complex stability and change in protein conformation. The result showed energetically favorable and stable complex formation in terms of RMSD, RMSF, SASA, Rg, and hydrogen bond formation. Drug likeness and physiochemical properties of the test compounds exhibited satisfactory results. Taken together, the present study suggests the presence of potential anti-SARS-CoV-2 phytochemicals in W. somnifera that requires further validation in in vitro and in vivo studies.

Graphical Abstract

Supplementary information

The online version contains supplementary material available at 10.1007/s42535-022-00404-4.

Targeting Breast Cancer-Derived Stem Cells by Dietary Phytochemicals: A Strategy for Cancer Prevention and Treatment

Breast cancer is heterogeneous disease with variable prognosis and therapeutic response. Approximately, 70% of diagnosed breast cancer represents the luminal A subtype. This subpopulation has a fair prognosis with a lower rate of relapse than the other clinical subtypes. Acquisition of stemness in luminal A subtype modifies the phenotype plasticity to accomplish increased aggressiveness and therapeutic resistance. Therefore, targeting luminal A-derived breast cancer stem cells (BCSCs) could be a promising strategy for its prevention and treatment. Extensive studies reveal that dietary phytochemicals have the potential to target BCSCs by modulating the molecular and signal transduction pathways. Dietary phytochemicals alone or in combination with standard therapeutic modalities exert higher efficacy in targeting BCSCs through changes in stemness, self-renewal properties and hypoxia-related factors. These combinations offer achieving higher radio- and chemo- sensitization through alteration in the key signaling pathways such as AMPK, STAT3, NF-ĸB, Hedgehog, PI3K/Akt/mTOR, Notch, GSK3β, and Wnt related to cancer stemness and drug resistance. In this review, we highlight the concept of targeting luminal A-derived BCSCs with dietary phytochemicals by summarizing the pathways and underlying mechanism(s) involved during therapeutic resistance.

Five-Decade Update on Chemopreventive and Other Pharmacological Potential of Kurarinone: a Natural Flavanone

In the present article we present an update on the role of chemoprevention and other pharmacological activities reported on kurarinone, a natural flavanone (from 1970 to 2021). To the best of our knowledge this is the first and exhaustive review of kurarinone. The literature was obtained from different search engine platforms including PubMed. Kurarinone possesses anticancer potential against cervical, lung (non-small and small), hepatic, esophageal, breast, gastric, cervical, and prostate cancer cells. In vivo anticancer potential of kurarinone has been extensively studied in lungs (non-small and small) using experimental xenograft models. In in vitro anticancer studies, kurarinone showed IC₅₀ in the range of 2–62 µM while in vivo efficacy was studied in the range of 20–500 mg/kg body weight of the experimental organism. The phytochemical showed higher selectivity toward cancer cells in comparison to respective normal cells. kurarinone inhibits cell cycle progression in G2/M and Sub-G1 phase in a cancer-specific context. It induces apoptosis in cancer cells by modulating molecular players involved in apoptosis/anti-apoptotic processes such as NF-κB, caspase 3/8/9/12, Bcl2, Bcl-XL, etc. The phytochemical inhibits metastasis in cancer cells by modulating the protein expression of Vimentin, N-cadherin, E-cadherin, MMP2, MMP3, and MMP9. It produces a cytostatic effect by modulating p21, p27, Cyclin D1, and Cyclin A proteins in cancer cells. Kurarinone possesses stress-mediated anticancer activity and modulates STAT3 and Akt pathways. Besides, the literature showed that kurarinone possesses anti-inflammatory, anti-drug resistance, anti-microbial (fungal, yeast, bacteria, and Coronavirus), channel and transporter modulation, neuroprotection, and estrogenic activities as well as tyrosinase/diacylglycerol acyltransferase/glucosidase/aldose reductase/human carboxylesterases 2 inhibitory potential. Kurarinone also showed therapeutic potential in the clinical study. Further, we also discussed the isolation, bioavailability, metabolism, and toxicity of Kurarinone in experimental models.

Identification of cancer stemness related miRNA(s) using integrated bioinformatics analysis and in vitro validation

The stemness property of cells allows them to sustain their lineage, differentiation, proliferation, and regeneration. MicroRNAs are small non-coding RNAs known to regulate the stemness property of cells by regulating the expression of stem cell signaling pathway proteins at mRNA level. Dysregulated miRNA expression and associated stem cell signaling pathways in normal stem cells give rise to cancer stem cells. Thus, the present study was aimed to identify the miRNAs involved in the regulation of major stem cell signaling pathways. The proteins (n = 36) involved in the signaling pathways viz., Notch, Wnt, JAK-STAT, and Hedgehog which is associated with the stemness property was taken into the consideration. The miRNAs, having binding sites for the targeted protein-encoding gene were predicted using an online tool (TargetScan) and the common miRNA among the test pathways were identified using Venn diagram analysis. A total of 22 common miRNAs (including 8 non-studied miRNAs) were identified which were subjected to target predictions, KEGG pathway, and gene ontology (GO) analysis to study their potential involvement in the stemness process. Further, we studied the clinical relevance of the non-studied miRNAs by performing the survival analysis and their expression levels in clinical breast cancer patients using the TCGA database. The identified miRNAs showed overall poor survival in breast cancer patients. The miR-6844 showed significantly high expression in various clinical subgroups of invasive breast cancer patients compared with the normal samples. The expression levels of identified miRNA(s) were validated in breast normal, luminal A, triple-negative, and stem cells in vitro models using qRT-PCR analysis. Further treatment with the phytochemical showed excellent down regulation of the lead miRNA. Overall the study first time reports the association of four miRNAs (miR-6791, miR-4419a, miR-4251 and miR-6844) with breast cancer stemness.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-02994-3.

Identification of Natural Inhibitors Against SARS-CoV-2 Drugable Targets Using Molecular Docking, Molecular Dynamics Simulation, and MM-PBSA Approach

The present study explores the SARS-CoV-2 drugable target inhibition efficacy of phytochemicals from Indian medicinal plants using molecular docking, molecular dynamics (MD) simulation, and MM-PBSA analysis. A total of 130 phytochemicals were screened against SARS-CoV-2 Spike (S)-protein, RNA-dependent RNA polymerase (RdRp), and Main protease (M^pro). Result of molecular docking showed that Isoquercetin potentially binds with the active site/protein binding site of the Spike, RdRP, and Mpro targets with a docking score of -8.22, -6.86, and -9.73 kcal/mole, respectively. Further, MS 3, 7-Hydroxyaloin B, 10-Hydroxyaloin A, showed -9.57, -7.07, -8.57 kcal/mole docking score against Spike, RdRP, and M^pro targets respectively. The MD simulation was performed to study the favorable confirmation and energetically stable complex formation ability of Isoquercetin and 10-Hydroxyaloin A phytochemicals in M^pro-unbound/ligand bound/standard inhibitor bound system. The parameters such as RMSD, RMSF, Rg, SASA, Hydrogen-bond formation, energy landscape, principal component analysis showed that the lead phytochemicals form stable and energetically stabilized complex with the target protein. Further, MM-PBSA analysis was performed to compare the Gibbs free energy of the M^pro-ligand bound and standard inhibitor bound complexes. The analysis revealed that the His-41, Cys145, Met49, and Leu27 amino acid residues were majorly responsible for the lower free energy of the complex. Drug likeness and physiochemical properties of the test compounds showed satisfactory results. Taken together, the study concludes that that the Isoquercetin and 10-Hydroxyaloin A phytochemical possess significant efficacy to bind SARS-Cov-2 M^pro active site. The study necessitates further in vitro and in vivo experimental validation of these lead phytochemicals to assess their anti-SARS-CoV-2 potential.

Induction of apoptosis in breast cancer cells by naphthylisoquinoline alkaloids

Breast cancer is one of the most common types of cancer in the world and a major cause of mortality. Present therapeutic strategies against breast cancer have severe drawbacks such as allergies, damage to healthy tissues, reoccurrence of cancer, and emergence of drug resistance. Naphthylisoquinoline alkaloids are a group of structurally unique natural products produced by tropical lianas belonging to the plant families Dioncophyllaceae and Ancistrocladaceae indigenous to Asia and Africa. These secondary metabolites have been reported to show anti-infective activity, but they also act against leukemic and pancreatic cancer cells. In the present study we have tested the potential of eleven mono- and dimeric naphthylisoquinoline compounds against two breast cancer cell lines, MCF-7 and MDA-MB-231. Three out of the compounds (agents 1, 4, and 11) showed significant activities against both tested cancer cell lines. Further mechanistic investigations revealed that all of the three substances induce apoptotic cell death via its intrinsic pathway by causing deformation of the nuclear membrane, disruption of the mitochondrial membrane potential (MMP), and elevated reactive oxygen species (ROS) production in both cell lines. Flow cytometric analysis using Annexin V - FITC/PI double staining showed an increased number of apoptotic cells in both, the early and the late phases.