TOP2A Research Articles

IND-2, a Quinoline Derivative, Inhibits the Proliferation of Prostate Cancer Cells by Inducing Oxidative Stress, Apoptosis and Inhibiting Topoisomerase II.

In men, prostate cancer (PC) is the most frequently diagnosed cancer, causing an estimated 375,000 deaths globally. Currently, existing therapies for the treatment of PC, notably metastatic cases, have limited efficacy due to drug resistance and problematic adverse effects. Therefore, it is imperative to discover and develop novel drugs for treating PC that are efficacious and do not produce intolerable adverse or toxic effects. Condensed quinolines are naturally occurring anticancer compounds. In this study, we determined the in vitro efficacy of IND-2 (4-chloro-2-methylpyrimido[1″,2″:1,5]pyrazolo[3,4-b]quinolone) in the PC lines, PC-3 and DU-145. IND-2 significantly inhibited the proliferation of PC-3 and DU-145, with IC50 values of 3 µM and 3.5 µM, respectively. The incubation of PC-3 cells with 5 and 10 µM of IND-2 caused the loss of the mitochondrial membrane potential in PC-3 cells. Furthermore, IND-2, at 5 µM, increased the expression of cleaved caspase-3, cleaved caspase-7 and cleaved poly (ADP-ribose) polymerase (PARP). The incubation of PC-3 cells with 5 µM of IND-2 significantly decreased the expression of the apoptotic protein, B-cell lymphoma 2 (Bcl-2). Furthermore, 5 and 10 µM of IND-2 produced morphological changes in PC-3 cells characteristic of apoptosis. Interestingly, IND-2 (2.5, 5 and 10 µM) also induced mitotic catastrophe in PC-3 cells, characterized by the accumulation of multinuclei. The incubation of DU-145 cells with 1.25 and 5 μM of IND-2 significantly increased the levels of reactive oxygen species (ROS). Finally, IND-2, at 10 μM, inhibited the catalytic activity of topoisomerase IIα. Overall, our findings suggest that IND-2 could be a potential lead compound for the development of more efficacious compounds for the treatment of PC.

Synthesis and biological properties of palladium(II) cyclometallated compounds derived from (E)-2-((4-hydroxybenzylidene)amino)phenol

(E)-2-((4-hydroxybenzylidene)amino)phenol (iminophenol a) reacted with Pd(OAc)2 giving place to compound 1a, in which the iminophenol was bonded to palladium(II) in a κ3-Cortho,N,Oortho tridentate chelating mode. Thus, 1a was formed by neutral mononuclear units of schematic formula Pd(C,N,O), consisting of two fused five-membered metallacycles. Self-assembly of the Pd(C,N,O) units gave place to the polynuclear structure of 1a. Treatment of 1a with PPh3 or PPh2CH2CH2PPh2 in molar ratio Pd(II)/PPh3 = 1/1 or Pd(II)/PPh2CH2CH2PPh2 = 2/1 produced the mononuclear or dinuclear compound of schematic formula [Pd(C,N,O)(PPh3)] (2a) or {[Pd(C,N,O)]2(µ2-PPh2CH2CH2PPh2)} (3a), respectively. Compounds a were characterized by elemental analysis, high resolution ESI-(+) mass spectrometry, IR, and NMR. In addition, the crystal structure of the adducts 2a·2(CH2Cl-CH2Cl) and 3a·5(dmso) was determined by single crystal X-ray diffraction analysis. Most compounds a were noncytotoxic or poorly cytotoxic. Nonetheless, 2a was moderately cytotoxic against the MCF-7 breast and HCT-116 colon human cancer cell lines, and presented very low cytotoxicity towards normal skin human BJ cells. Compounds a showed moderate antibacterial activity against some Gram-positive (B. subtilis and S. aureus) and Gram-negative (E. coli) bacterial strains, and displayed also moderate antioxidant activity, producing 3a the best antioxidant activity. 1a changed the electrophoretic mobility of the pBluescript SK+ plasmid DNA. This change followed the pattern of cisplatin, but it started at a concentration twenty times higher than with cisplatin. Moreover, compounds 1a - 3a inhibited topoisomerase IIα at concentrations of 10, 50 and 25 µM, respectively.

Orthopalladated N,N-dimethyl-1-phenethylamine compounds containing 2,6-lutidine: Synthesis, DNA binding studies and cytotoxicity evaluation

Metathetical reactions involving [Pd(C2,N-dmpa)(μ-Cl)]2 (1) and the appropriate halides/pseudohalides salts afforded cyclopalladated dimers of the type [Pd(C2,N-dmpa)(μ-X)]2 (dmpa = S(−) enantiomer of N,N-dimethyl-1-phenethylamine; {X = Cl (1) and N3 (2)}. Mononuclear compounds of general formulae [Pd(C2,N-dmpa)(X)(lut)] {X = Cl (1a) and N3 (2a)} were obtained by bridge-splitting reactions involving the corresponding [Pd(C2,N-dmpa)(μ-X)]2 with 2,6-lutidine (lut) in the 1:2 M ratio at room temperature. Both the cyclopalladated compounds were characterized by means of elemental analysis, FT-IR, Raman, 1H and 13C NMR spectroscopy. The antiproliferative activity of the mononuclear compounds 1a-2a was evaluated towards human glioblastoma (U251 and T98G) and melanoma cell lines (HT144 and LB373) and their IC50 values determined between 1 and 6 μM. In most cases, the cytotoxic effects of compounds 1a-2a showed to be similar to those of cisplatin (depending on the cell line), what is of utmost importance when considering treatment alternatives for these aggressive tumor types. Binding studies on the representative compound 2a towards ct-DNA, however, showed low or no affinity, suggesting that the observed cytotoxicity against the human cell lines may involve different mechanisms of action compared to that of the platinum-based chemotherapy drug. The ability of 1a to induce the inhibition of topoisomerase IIα activity has also been investigated. These cyclopalladated compounds can be transported and distributed through the body by human serum albumin (HSA), as observed by competition and computational studies with the protein. These findings are very promising and have motivated further studies for the design of new and bioactive cyclopalladated compounds for future medicinal purposes.

Identification of the first-in-class dual inhibitors of human DNA topoisomerase IIα and indoleamine-2,3-dioxygenase 1 (IDO 1) with strong anticancer properties

Molecular docking of a large set of thiosemicarbazide-based ligands resulted in obtaining compounds that inhibited both human DNA topoisomerase IIα and indoleamine-2,3-dioxygenase-1 (IDO1). To the best of our knowledge, these compounds are the first dual inhibitors targeting these two enzymes. As both of them participate in the anticancer response, the effect of the compounds on a panel of cancer cell lines was examined. Among the cell lines tested, lung cancer (A549) and melanoma (A375) cells were the most sensitive to compounds 1 (IC50=0.23 µg/ml), 2 (IC50=0.83 µg/ml) and 3 (IC50=0.25 µg/ml). The observed activity was even 90-fold higher than that of etoposide, with selectivity index values reaching 125. In-silico simulations showed that contact between 1-3 and human DNA topoisomerase II was maintained through aromatic moieties located at limiting edges of ligand molecules and intensive interactions of the thiosemicarbazide core with the DNA fragments present in the catalytic site of the enzyme.

Custom gene expression panel for evaluation of potential molecular markers in hepatocellular carcinoma

BackgroundHepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. It is a highly heterogeneous disease with poor prognosis and limited treatment options, which highlights the need for reliable biomarkers. This study aims to explore molecular markers that allow stratification of HCC and may lead to better prognosis and treatment prediction.Materials and methodsWe studied 20 candidate genes (HCC hub genes, potential drug target genes, predominant somatic mutant genes) retrieved from literature and public databases with potential to be used as the molecular markers. We analysed expression of the genes by RT-qPCR in 30 HCC tumour and adjacent non-tumour paired samples from Vietnamese patients. Fold changes in expression were then determined using the 2−∆∆CT method, and unsupervised hierarchical clustering was generated using Cluster v3.0 software.ResultsClustering of expression data revealed two subtypes of tumours (proliferative and normal-like) and four clusters for genes. The expression profiles of the genes TOP2A, CDK1, BIRC5, GPC3, IGF2, and AFP were strongly correlated. Proliferative tumours were characterized by high expression of the c-MET, ARID1A, CTNNB1, RAF1, LGR5, and GLUL1 genes. TOP2A, CDK1, and BIRC5 HCC hub genes were highly expressed (> twofold) in 90% (27/30), 83% (25/30), and 83% (24/30) in the tissue samples, respectively. Among the drug target genes, high expression was observed in the GPC3, IGF2 and c-MET genes in 77% (23/30), 63% (19/30), and 37% (11/30), respectively. The somatic mutant Wnt/ß-catenin genes (CTNNB1, GLUL and LGR5) and TERT were highly expressed in 40% and 33% of HCCs, respectively. Among the HCC marker genes, a higher percentage of tumours showed GPC3 expression compared to AFP expression [73% (23/30) vs. 43% (13/30)].ConclusionThe custom panel and molecular markers from this study may be useful for diagnosis, prognosis, biomarker-guided clinical trial design, and prediction of treatment outcomes.

New synthetic quinaldine conjugates: Assessment of their anti-cholinesterase, anti-tyrosinase and cytotoxic activities, and molecular docking analysis

• Synthesis of new quinoline-succinimide derivatives. • Synthesized derivatives were screened for their anti-tyrosinase and cytotoxic activities. • Compounds 3d , 3e and 3 g showed interesting tyrosinase inhibitory activities. • Compounds 3f , 3 g and 3a displayed the highest activity against HeLa cell lines. • Molecular docking analysis reinforced the experimental results. Despite all the progress made to enrich the existing bank of drugs used to treat and cure Alzheimer and cancer patients, there is still a need to research and develop new bioactive candidates with superior efficacy but minimal side effects. In this context, a new series of anti-butyrylcholinesterase (anti-BChE), anti-tyrosinase and cytotoxic succinimide linked quinaldine conjugates 3a-i was designed and synthesized starting from 8-hydroxyquinaldine. The condensation of quinoleine-hydrazide 2 with electrophilic species such as aromatic and nonaromatic anhydrides provided the new compounds 3a-i . These synthesized heterocycles were characterized by spectroscopic means ( 1 H NMR, 13 C NMR and ESI-HRMS). Their anti-butyrylcholinesterase, anti-tyrosinase and cytotoxic (cervical cancer cell (HeLa) and lung cancer cell (A549)) activities have been evaluated in vitro . Compounds 3e and 3 g were found to be more anti-BChE than Galanthamine. Compounds 3d , 3e and 3 g exerted better anti-tyrosinase activity than kojic acid. Also, 3a , 3f and 3 g showed interesting cytotoxic potential towards HeLa cell lines. These results were supported by the molecular docking analysis (structure–activity relationship (SAR)) to estimate and discuss possible interactions between these derivatives and active sites of proteins butyrylcholinesterase (PDB: 4B0P), tyrosinase (PDB: 2Y9X) and cytotoxic (topoisomerase IIα enzyme (PDB: 5GWK)).

Anthracycline-induced cardiotoxicity and cell senescence: new therapeutic option?

Anthracyclines are chemotherapeutic drugs widely used in the frontline of cancer treatment. The therapeutic mechanisms involve the stabilization of topoisomerase IIα, DNA, and the anthracycline molecule in a ternary complex that is recognized as DNA damage. Redox imbalance is another vital source of oxidative DNA damage. Together, these mechanisms lead to cytotoxic effects in neoplastic cells. However, anthracycline treatment can elicit cardiotoxicity and heart failure despite the therapeutic benefits. Topoisomerase IIβ and oxidative damage in cardiac cells have been the most reported pathophysiological mechanisms. Alternatively, cardiac cells can undergo stress-induced senescence when exposed to anthracyclines, a state primarily characterized by cell cycle arrest, organelle dysfunction, and a shift to senescence-associated secretory phenotype (SASP). The SASP can propagate senescence to neighboring cells in an ongoing process that leads to the accumulation of senescent cells, promoting cellular dysfunction and extracellular matrix remodeling. Therefore, the accumulation of senescent cardiac cells is an emerging pathophysiological mechanism associated with anthracycline-induced cardiotoxicity. This paradigm also raises the potential for therapeutic approaches to clear senescent cells in treating anthracycline-induced cardiotoxicity (i,e, senolytic therapies).

DNA Topoisomerase II-α Regulated by miR-22-5p Promotes Hepatocellular Carcinoma Invasion and Migration through the Hippo Pathway.

DNA topoisomerases (TOPs) are dysregulated in various types of cancer. However, how TOP II-alpha (TOP2A) contributes to hepatocellular carcinoma (HCC) progression remains elusive. Cohort analysis revealed that the increased expression of TOP2A was associated with poor clinical outcomes and TOP2A was significantly upregulated in HCC tissues and cell lines. In vitro, TOP2A expression level is related to cell invasion and migration, which may be due to the alteration of epithelial-mesenchymal transition by the TOP2A. Moreover, we used verteporfin (a Hippo inhibitor) to test how the Hippo pathway promotes the effect of TOP2A on the HCC phenotype and found that TOP2A induces tumor progression through the Hippo pathway. Finally, miR-22-5p inhibited tumor progression by sponging TOP2A.

Adaptive resistance is not responsible for long-term drug resistance in a cellular model of triple negative breast cancer

Resistance to cancer therapeutics represents a leading cause of mortality and is particularly important in cancers, such as triple negative breast cancer, for which no targeted therapy is available, as these are only treated with traditional chemotherapeutics. Cancer, as well as bacterial, drug resistance can be intrinsic, acquired or adaptive. Adaptive cancer drug resistance is gaining attention as a mechanism for the generation of long-term drug resistance as is the case with bacterial antibiotic resistance. We have used a cellular model of triple negative breast cancer (CAL51) and its drug resistance derivative (CALDOX) to gain insight into genome-wide expression changes associated with long-term doxorubicin (a widely used anthracycline for cancer treatment) resistance and doxorubicin-induced stress. Previous work indicates that both naïve and resistance cells have a functional p53-p21 axis controlling cell cycle at G1, although this is not a driver for drug resistance, but down-regulation of TOP2A (topoisomerase IIα). As expected, CALDOX cells have a signature characterized, in addition to down-regulation of TOP2A, by genes and pathways associated with drug resistance, metastasis and stemness. Both CAL51 and CALDOX stress signatures share 12 common genes (TRIM22, FAS, SPATA18, SULF2, CDKN1A, GDF15, MYO6, CXCL5, CROT, EPPK1, ZMAT3 and CD44), with roles in the above-mentioned pathways, indicating that these cells have similar functional responses to doxorubicin relaying on the p53 control of apoptosis. Eight genes are shared by both drug stress signatures (in CAL51 and CALDOX cells) and CALDOX resistant cells (FAS, SULF2, CDKN1A, CXCL5, CD44, SPATA18, TRIM22 and CROT), many of them targets of p53. This corroborates experimental data indicating that CALDOX cells, even in the absence of drug, have activated, at least partially, the p53-p21 axis and DNA damage response. Although this eight-gene signature might be an indicator of adaptive resistance, as this transient phenomenon due to short-term stress may not revert to its original state upon withdrawal of the stressor, previous experimental data indicates that the p53-p21 axis is not responsible for doxorubicin resistance. Importantly, TOP2A is not responsive to doxorubicin treatment and thus absent in both drug stress signatures. This indicates that during the generation of doxorubicin resistance, cells acquire genetic changes likely to be random, leading to down regulation of TOP2A, but selected during the generation of cells due to the presence of drug in the culture medium. This poses a considerable constraint for the development of strategies aimed at avoiding the emergence of drug resistance in the clinic.

Selective Cytotoxic Constituents from Gardenia latifolia and their In Silico Topoisomerase IIα Inhibition

Background: The search for natural anticancer agents is a worthy scientific research goal, driven by the hope to lessen cancer's tremendous global burden. Objective: This study aimed at evaluating the cytotoxic activity of Gardenia latifolia Ait. (Rubiaceae) against lung (A549) and colon (HCT116) cancer cell lines. Cytotoxicity-guided isolation of the bioactive phytochemicals was conducted, followed by various mechanistic validations of the appealing cytotoxic metabolites. Methods: The cytotoxic effects were determined using MTT assay. The two most cytotoxic compounds were further evaluated for their effects on cell cycle progression and apoptotic capabilities using flow cytometry approach. Additionally, we conducted a molecular docking analysis to reveal their potential interactions with the human topoisomerase IIα. Results: The phytochemical investigation led to isolation of nine compounds including a new one, (-) 1-acetyl 4,5-di-O-caffeoyl quinic acid. The latter compound was the most cytotoxic against the colon cancer cell line (IC50 1.9 µg/ml) with a remarkable tumor-selectivity (SI ≈ 15). Moreover, the isolated glycoside, 1-O-[6-O-(5-O-vanilloyl-β-ᴅ-apiofuranosyl)-β-ᴅ-glucopyranosyl]-3,4,5-trimethoxybenzene, showed selective cytotoxicity towards A549 and HCT116 cells (IC50 values of 3.8 and 3.3 µg/ml, respectively). Both compounds considerably affected the cell cycle distribution. They caused G2/M cell cycle arrest, showed apoptotic capabilities, and displayed significant in silico topoisomerase IIα inhibition. Conclusion: Two cytotoxic and apoptotic compounds were reported from Gardenia latifolia. Subsequent in vivo studies and clinical trials should be conducted to substantiate their anticipated therapeutic values.

TOP2A deficit-induced abnormal decidualization leads to recurrent implantation failure via the NF-κB signaling pathway

BackgroundSuccessful implantation is a complex process that is influenced by embryo quality, endometrial receptivity, immune factors, and the specific type of in vitro fertilization protocol used. DNA topoisomerase IIα (TOP2A) is a well-known protein involved in cell proliferation; however, its expression and effect on the endometrium in recurrent implantation failure (RIF) have not been fully elucidated.MethodsThe human endometrial tissues of healthy controls and patients with RIF were collected. A proteomic analysis was performed to evaluate the differentially expressed proteins between the RIF group and the fertile control group. The expression patterns of TOP2A in the human preimplantation endometrium of the patients with RIF were determined by immunohistochemical staining, Western blotting and qRT-PCR. TOP2A knockdown (sh-TOP2A) T-HESCs were generated using lentiviruses. The expression of TOP2A in T-HESCs was manipulated to investigate its role in decidualization. The TOP2A-related changes in decidualization were screened by mRNA sequencing in decidualized TOP2A knockdown and control T-HESCs and then confirmed by Western blotting and immunofluorescence staining. TOP2A-deficient mice were generated by injection of TOP2A-interfering adenovirus on GD2.5 and GD3.5.ResultsWe performed a proteomic analysis of endometrial tissues to investigate the potential pathogenesis of RIF by comparing the patients with RIF and the matched controls and found that TOP2A might be a key protein in RIF. TOP2A is ubiquitously expressed in both stromal and glandular epithelial cells of the endometrium. The data indicate that TOP2A expression is significantly lower in the mid-secretory endometrium of women with RIF. TOP2A expression was downregulated under stimulation by 8-bromo-cAMP and MPA. Ablation of TOP2A resulted in upregulated expression of decidual biomarkers and morphological changes in the cells. Mechanistic analysis revealed that TOP2A regulates the NF-κB signaling pathway in decidualized T-HESCs. The TOP2A-deficient mice exhibited lower fetal weights.ConclusionsOur findings revealed that abnormal expression of TOP2A affects decidualization and changes the “window of implantation”, leading to RIF. TOP2A participates in the processes of decidualization and embryo implantation, functioning at least in part through the NF-κB pathway. Regulating the expression of TOP2A in the endometrium may become a new strategy for the prevention and treatment of RIF.

Recognition of DNA Supercoil Handedness during Catenation Catalyzed by Type II Topoisomerases.

Although the presence of catenanes (i.e., intermolecular tangles) in chromosomal DNA stabilizes interactions between daughter chromosomes, a lack of resolution can have serious consequences for genomic stability. In all species, from bacteria to humans, type II topoisomerases are the enzymes primarily responsible for catenating/decatenating DNA. DNA topology has a profound influence on the rate at which these enzymes alter the superhelical state of the double helix. Therefore, the effect of supercoil handedness on the ability of human topoisomerase IIα and topoisomerase IIβ and bacterial topoisomerase IV to catenate DNA was examined. Topoisomerase IIα preferentially catenated negatively supercoiled over positively supercoiled substrates. This is opposite to its preference for relaxing (i.e., removing supercoils from) DNA and may prevent the enzyme from tangling the double helix ahead of replication forks and transcription complexes. The ability of topoisomerase IIα to recognize DNA supercoil handedness during catenation resides in its C-terminal domain. In contrast to topoisomerase IIα, topoisomerase IIβ displayed little ability to distinguish DNA geometry during catenation. Topoisomerase IV from three bacterial species preferentially catenated positively supercoiled substrates. This may not be an issue, as these enzymes work primarily behind replication forks. Finally, topoisomerase IIα and topoisomerase IV maintain lower levels of covalent enzyme-cleaved DNA intermediates with catenated over monomeric DNA. This allows these enzymes to perform their cellular functions in a safer manner, as catenated daughter chromosomes may be subject to stress generated by the mitotic spindle that could lead to irreversible DNA cleavage.

Synthesis and Evaluation of Antiproliferative Activity, Topoisomerase IIα Inhibition, DNA Binding and Non-Clinical Toxicity of New Acridine-Thiosemicarbazone Derivatives.

In this study, we report the synthesis of twenty new acridine–thiosemicarbazone derivatives and their antiproliferative activities. Mechanisms of action such as the inhibition of topoisomerase IIα and the interaction with DNA have been studied for some of the most active derivatives by means of both in silico and in vitro methods, and evaluations of the non-clinical toxicities (in vivo) in mice. In general, the compounds showed greater cytotoxicity against B16-F10 cells, with the highest potency for DL-08 (IC50 = 14.79 µM). Derivatives DL-01 (77%), DL-07 (74%) and DL-08 (79%) showed interesting inhibition of topoisomerase IIα when compared to amsacrine, at 100 µM. In silico studies proposed the way of bonding of these compounds and a possible stereoelectronic reason for the absence of enzymatic activity for CL-07 and DL-06. Interactions with DNA presented different spectroscopic effects and indicate that the compound CL-07 has higher affinity for DNA (Kb = 4.75 × 104 M−1; Ksv = 2.6 × 103 M−1). In addition, compounds selected for non-clinical toxicity testing did not show serious signs of toxicity at the dose of 2000 mg/kg in mice; cytotoxic tests performed on leukemic cells (K-562) and its resistant form (K-562 Lucena 1) identified moderate potency for DL-01 and DL-08, with IC50 between 11.45 and 17.32 µM.

Ki-67, topoisomerase IIα and miR-221 have a limited prostate cancer risk stratification ability on a medium-term follow-up: results of a high-risk radical prostatectomy cohort.

BackgroundCurrently, no biomarkers are able to differentiate lethal from relatively indolent prostate cancer (PCa) within high-risk diseases. Nonetheless, several molecules are under investigation. Amongst them, topoisomerase-II-alpha (TOPIIA), Ki67 and miR-221 showed promising results. Our aim was to investigate their prognostic role in the context of biochemical recurrence (BCR), clinical recurrence (CR) and PCa-related death (PcD).MethodsWe included 64 consecutive cM0 high-risk PCa [prostate specific antigen (PSA) >20 ng/mL or Gleason Score (GS) >7 or cT >2] undergoing radical prostatectomy (RP). Changes in miR-221 expression and alternative splicing were determined using microarrays. Immunohistochemical determination of Ki67 and TOPIIa were performed using monoclonal antibody MIB-1 and 3F6 respectively. Cox proportional-hazards regression models were used to predict BCR and CR as multivariate analysis. BCR and CR were defined as three consecutive rises in PSA and PSA >0.2 ng/mL and histologically-proven local recurrence or imaging positive for distant metastasis respectively.ResultsWe included 64 men. Mean pre-operative PSA was 26.53 (range, 1.3–135); all GSs were ≥7 and pT was ≥ T3 in 78.13%. Positive margins and lymph-nodes were present in 42.19% and 32.81% respectively. At a mean follow-up of 5.7 years (range, 1.8–12.5), 42.18% experienced BCR (n=27), 29.68% CR (n=19) and 7.81% PcD (n=5). On univariate analysis positive nodes (<0.01), seminal vesicle invasion (0.02) and miR-221 downregulation (P=0.03), but not Ki67 and TOPIIA (both P>0.5) were associated with BCR whereas only PSA (P<0.01), seminal vesicle invasion (P<0.01) and positive nodes (both P<0.01) were linked to CR. No parameters predicted PcD (all P>0.05) or BCR and CR on multivariate analysis (all P>0.05 - miR-221 HR 0.776; 95% CI: 0.503–1.196 for BCR and HR 0.673; 95% CI: 0.412–1.099 for CR). Limitation of the study include its small sample size and limited follow-up.ConclusionsTOPIIA, Ki-67 and miR-221 may not predict BCR, CR or PcD in high-risk PCa patients who underwent RP at a medium-term follow-up. Longer follow-up and larger cohorts are needed to confirm our findings.

Topoisomerase Enzyme Inhibitors as Potential Drugs Against Cancer: What Makes Them Selective or Dual? - A Review.

Topoisomerase inhibitors are extensively used in cancer chemotherapy. In the process of identifying novel anticancer compounds, biological evaluations are crucial and include, among others, the use of in silico and in vitro approaches. This work aimed to present recent research involving the obtainment and in silico and in vitro evaluation of topoisomerase I, II, and double inhibitors, of synthetic and natural origin, as potential compounds against tumor cells, in addition to proposing the construction of a desirable enzyme catalytic site. Therefore, it was observed that most Topoisomerase I inhibitors presented medium to large structures, with a rigid portion and a flexible region. In contrast, Topoisomerase IIα inhibitors showed medium and large structural characteristics, in addition to the planarity of the aromatic rings, which are mitigated due to flexible rings but may also present elements that restrict conformation. Most compounds that exhibit dual inhibitory activity had relatively long chains, in addition to a flat and rigid portion suggestive of affinity for Topo I and a flexible region characteristic of selective drugs for Topo II. Besides, it is noticed that most compounds that exhibit dual inhibitory showed similarities in the types of interactions and amino acids when compared to the selective compounds of Topo I and II. For instance, selective Topoisomerase I inhibitors interact with Arginine364 residues, and selective Topoisomerase II inhibitors interact with Arginine487 residues, as both residues are targets for dual compounds.

Inter-component immunohistochemical assessment of proliferative markers in uterine carcinosarcoma.

In the scientific literature, a selected number of reports have investigated the impact of proliferative activity on the development and progression of uterine carcinosarcomas (UC). The aim of the present retrospective study was to compare the immunohistochemical proliferation markers [Ki67, proliferating cell nuclear antigen (PCNA), minichromosome maintenance complex component 3 (MCM3), and topoisomerase IIα (topoIIα)] assessment in both components of UC. A total of 30 paraffin-embedded slides of UCs, obtained from patients who underwent surgery between January 1, 2006, and December 31, 2020, were analyzed. Medical records and clinicopathological data of patients were reviewed. Formalin-fixed, paraffin-embedded tissue sections were immunostained with monoclonal antibodies against Ki67, PCNA, MCM3 and topoIIα. Ki67-positive nuclear immunoreactivity was reported in 20 (67%) and 16 (53%) UC carcinomatous and sarcomatous components, respectively. In the epithelial component, Ki67 positive staining was related to the International Federation of Gynecology and Obstetrics (FIGO) stage (P=0.025), and histological grade (G1 vs. G2/G3, P=0.031). Nuclear PCNA reactivity was observed in 18 (60%) and 16 (53%) carcinomatous and sarcomatous components, respectively. Notably, all four cases with omental metastases were PCNA-positive, and a relationship between staining pattern and the existence of metastases was of significant value (P=0.018). MCM3-positive nuclear staining was found nearly twice as high in the carcinomatous (n=19; 63%), compared with the sarcomatous (n=11; 37%) component, respectively, and MCM3 expression in the epithelial component was related to clinical stage (P=0.030), and the existence of omental metastasis (P=0.012). In addition, out of the 30 UCs, 17 (57%) and 13 (43%) showed topoIIα positivity in the carcinomatous and sarcomatous UC components, respectively. A significant relationship between protein immunoreactivity and FIGO stage (P=0.049), and omental metastasis (P=0.026) was revealed to exist. However, no significant differences between expression of proliferation markers and clinicopathological features in the sarcomatous UC component were identified. Finally, a significant correlation between each protein immunohistochemical staining was demonstrated, particularly in the sarcomatous UC component. Collectively, a combined analysis of Ki67, PCNA, MCM3, and topoIIα may provide more detailed information of cell-cycle alterations determining the heterogeneity of uterine carcinosarcomas.

Topoisomerase IIA in adult NSCs regulates SVZ neurogenesis by transcriptional activation of Usp37.

Topoisomerase IIA (TOP2a) has traditionally been known as an important nuclear enzyme that resolves entanglements and relieves torsional stress of DNA double strands. However, its function in genomic transcriptional regulation remains largely unknown, especially during adult neurogenesis. Here, we show that TOP2a is preferentially expressed in neurogenic niches in the brain of adult mice, such as the subventricular zone (SVZ). Conditional knockout of Top2a in adult neural stem cells (NSCs) of the SVZ significantly inhibits their self-renewal and proliferation, and ultimately reduces neurogenesis. To gain insight into the molecular mechanisms by which TOP2a regulates adult NSCs, we perform RNA-sequencing (RNA-Seq) plus chromatin immunoprecipitation sequencing (ChIP-Seq) and identify ubiquitin-specific protease 37 (Usp37) as a direct TOP2a target gene. Importantly, overexpression of Usp37 is sufficient to rescue the impaired self-renewal ability of adult NSCs caused by Top2a knockdown. Taken together, this proof-of-principle study illustrates a TOP2a/Usp37-mediated novel molecular mechanism in adult neurogenesis, which will significantly expand our understanding of the function of topoisomerase in the adult brain.

Novel Curcumin Mimics: Design, Synthesis, Biological Properties and Computational Studies of Piperidone‐Piperazine Conjugates

Abstract3,5‐Di[(E)‐arylidene]‐1‐[3‐(4‐methylpiperazin‐1‐yl)alkyl]piperidin‐4‐ones 7 a−k were synthesized through dehydrohalogenation of 1‐(2‐chloroacyl)piperidin‐4‐ones 5 a−k with N‐methylpiperazine (6). High antiproliferation potencies were observed by most of the synthesized agents against both HCT116 (colon) and MCF7 (breast) cancer cell lines relative to the standard references (sunitinib and 5‐fluorouracil). The synthesized agents are of dual activity against topoisomerases I and IIα however, with higher efficacy against topoisomerase IIα rather than topoisomerase I. Flow‐cytometry cell cycle studies support the observed antiproliferation properties and exhibit the capability of 1‐(2‐chloroacetyl)‐3,5‐bis[(E)‐4‐chlorobenzylidene]piperidin‐4‐one (5 e) and 3,5‐bis[(E)‐4‐bromobenzylidene]‐1‐[2‐(4‐methylpiperazin‐1‐yl)acetyl]piperidin‐4‐one (7 g) to arrest the HCT116 cell cycle progression at G1/S and G1 phases, respectively. Noticeable anti‐SARS‐CoV‐2 properties were observed by many synthesized agents. 3,5‐Bis[(E)‐4‐chlorobenzylidene]‐1‐[3‐(4‐methylpiperazin‐1‐yl)propanoyl]piperidin‐4‐one (7 f) is the most effective anti‐SARS‐CoV‐2 synthesized with high SI. Applicability of the highly effective candidates synthesized as antitumor and anti‐SARS‐CoV‐2 is due to the safety observations against normal (RPE1 and VERO‐E6) cells. QSAR models validated internally and externally, support their possibility for optimizing more hits/leads.

Chemical Composition of Various Nepeta cataria Plant Organs' Methanol Extracts Associated with In Vivo Hepatoprotective and Antigenotoxic Features as well as Molecular Modeling Investigations.

This report summarizes the chemical composition analysis of Nepeta cataria L. flower, leaf, and stem methanol extracts (FME, LME, SME, respectively) as well as their hepatoprotective and antigenotoxic features in vivo and in silico. Herein, Wistar rat liver intoxication with CCl4 resulted in the generation of trichloromethyl and trichloromethylperoxy radicals, causing lipid peroxidation within the hepatocyte membranes (viz. hepatotoxicity), as well as the subsequent formation of aberrant rDNA adducts and consequent double-strand break (namely genotoxicity). Examined FME, LME, and SME administered orally to Wistar rats before the injection of CCl4 exerted the most notable pharmacological properties in the concentrations of 200, 100, and 50 mg/kg of body weight, respectively. Thus, the extracts’ hepatoprotective features were determined by monitoring the catalytic activities of enzymes and the concentrations of reactive oxidative species, modulating the liver redox status. Furthermore, the necrosis of hepatocytes was assessed by means of catalytic activities of liver toxicity markers. The extracts’ antigenotoxic features were quantified using the comet assay. Distinct pharmacological property features may be attributed to quercitrin (8406.31 μg/g), chlorogenic acid (1647.32 μg/g), and quinic acid (536.11 μg/g), found within the FME, rosmarinic acid (1056.14 μg/g), and chlorogenic acid (648.52 μg/g), occurring within the LME, and chlorogenic acid (1408.43 μg/g), the most abundant in SME. Hence, the plant’s secondary metabolites were individually administered similar to extracts, upon which their pharmacology in vivo was elucidated in silico by means of the structure-based studies within rat catalase, as a redox marker, and rat topoisomerase IIα, an enzyme catalyzing the rat DNA double-strand break. Conclusively, the examined N. cataria extracts in specified concentrations could be used in clinical therapy for the prevention of toxin-induced liver diseases.

Pro-Apoptotic Antitumoral Effect of Novel Acridine-Core Naphthoquinone Compounds against Oral Squamous Cell Carcinoma.

Oral squamous cell carcinoma (OSCC) is a global public health problem with high incidence and mortality. The chemotherapeutic agents used in the clinic, alone or in combination, usually lead to important side effects. Thus, the discovery and development of new antineoplastic drugs are essential to improve disease prognosis and reduce toxicity. In the present study, acridine-core naphthoquinone compounds were synthesized and evaluated for their antitumor activity in OSCC cells. The mechanism of action, pharmacokinetics, and toxicity parameters of the most promising compound was further analyzed using in silico, in vitro, and in vivo methods. Among the derivatives, compound 4e was highly cytotoxic (29.99 µM) and selective (SI 2.9) at levels comparable and generally superior to chemotherapeutic controls. Besides, compound 4e proved to be non-hemolytic, stable, and well tolerated in animals at all doses tested. Mechanistically, compound 4e promoted cell death by apoptosis in the OSCC cell, and molecular docking studies suggested this compound possibly targets enzymes important for tumor progression, such as RSK2, PKM2, and topoisomerase IIα. Importantly, compound 4e presented a pharmacological profile within desirable parameters for drug development, showing promise for future preclinical trials.