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This research aimed to develop novel selective secosteroids that are highly active against hormone-dependent breast cancer. A simple and convenient approach to N'-acylated 13,17-secoestra-1,3,5(10)-trien-17-oic acid hydrazides was disclosed and these novel types of secosteroids were screened for cytotoxicity against the hormone-dependent human breast cancer cell line MCF7. Most secosteroid N'-benzoyl hydrazides have demonstrated high cytotoxicity against MCF7 cells with IC50 values below 5 µM, which are superior to that of the reference drug cisplatin. Hit compounds 2c, 2e and 2i were characterized by high cytotoxicity (IC50 = 1.6-1.9 µM) and very good selectivity towards MCF7 breast cancer cells. The lead secosteroids 2c, 2e and 2i also exhibit antiestrogenic effects and alter the expression of cell cycle regulating proteins. The effect of selected compounds on PARP (poly(ADP-ribose) polymerase) and Bcl-2 (B-cell CLL/lymphoma 2) indicates their proapoptotic potential. The synthesized secosteroids may be considered as new promising anti-breast cancer agents targeting ERα and apoptosis pathways.

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Combining chemotherapy and hormone therapy is a prevalent approach in breast cancer treatment. While the cytotoxic impact of numerous chemotherapy drugs stems from DNA damage, the exact role of these DNA alterations in modulating estrogen receptor α (ERα) machinery remains elusive. The present study aimed to analyze the impact of DNA damage agents on ERα signaling in breast cancer cells and assess the signaling pathways mediating the influence of DNA damage drugs on the ERα machinery. Cell viability was assessed using the MTT method, while the expression of signaling proteins was analyzed by immunoblotting. ERα activity in the cells treated with various drugs (17ß-estradiol, tamoxifen, 5-fluorouracil) was assessed through reporter gene assays. In vitro experiments were conducted on MCF7 breast cancer cells subjected to varying durations of 5-fluorouracil (5-FU) treatment. Two distinct cell responses to 5-FU were identified based on the duration of the treatment. A singular dose of 5-FU induces pronounced DNA fragmentation, temporally suppressing ERα signaling while concurrently activating AKT phosphorylation. This suppression reverses upon 5-FU withdrawal, restoring normalcy within ten days. However, chronic 5-FU treatment led to the emergence of 5-FU-resistant cells with irreversible alterations in ERα signaling, resulting in partial hormonal resistance. These changes mirror those observed in cells subjected to UV-induced DNA damage, underscoring the pivotal role of DNA damage in shaping estrogen signaling alterations in breast cancer cells. In summary, the results of the present study suggested that the administration of DNA damage agents to cancer cells can trigger irreversible suppression of estrogen signaling, fostering the development of partial hormonal resistance. This outcome may ultimately impede the efficacy of combined or subsequent chemo- and hormone therapy strategies.

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The treatment of tuberculosis is still a challenging process due to the widespread of pathogen strains resistant to antibacterial drugs, as well as the undesirable effects of anti-tuberculosis therapy. Hence, the development of safe and effective new anti-antitubercular agents, in addition to suitable nanocarrier systems, has become of utmost importance and necessity. Our research aims to develop liposomal vesicles that contain newly synthesized compounds with antimycobacterial action. The compound being studied is a derivative of imidazo-tetrazine named 3-(3,5-dimethylpyrazole-1-yl)-6-(isopropylthio) imidazo [1,2-b] [1,2,4,5] tetrazine compound. Several factors that affect liposomal characteristics were studied. The maximum encapsulation efficiency was 53.62 ± 0.09. The selected liposomal formulation T8* possessed a mean particle size of about 205.3 ± 3.94 nm with PDI 0.282, and zeta potential was + 36.37 ± 0.49 mv. The results of the in vitro release study indicated that the solubility of compound I was increased by its incorporation in liposomes. The free compound and liposomal preparation showed antimycobacterial activity against Mycobacterium tuberculosis H37Rv (ATCC 27294) at MIC value 0.94-1.88 µg/ml. We predict that the liposomes may be a good candidate for delivering new antitubercular drugs.

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INTRODUCTION: Dopamine (DA) is likely to be involved in some depressive dimensions, such as anhedonia and amotivation, which account for a part of treatment-resistant forms. Monoamine oxidase inhibitors (MAOI) and direct D2 and D3 receptors agonists (D2/3r-dAG) are known to help, but we lack safety data about their combined usage. We report on safety and tolerance of the MAOI+D2r-dAG combination in a clinical series. METHOD: All patients referred to our recourse center for depression between 2013 and 2021 were screened to select those who did receive the combo. Data were extracted from clinical files. RESULTS: Sixteen patients of 60±17 years of age (8 women, 7 with age>65years, all suffered from treatment resistant depression, 7 with bipolar disorder) received the combo. There were no life-threatening adverse effects (AE). However, AE were reported by 14 patients (88%) most of which were mild and consisted of insomnia, nausea, nervousness, confusion, impulse control disorder and/or "sleep attacks". One patient presented a serious AE requiring a short hospitalization for confusion. Intolerance led to failure to introduce treatment in two patients (13%). The retrospective non-interventional design, the variety of molecules, and the modest sample size limited the scope of these results. CONCLUSION: There was no life-threatening safety issue in combining MAOI and D2/3r-dAG, especially regarding cardiovascular side effects. The systematic screening of AE might account for their frequency, but these precluded the treatment in only two patients. Comparative studies are needed to assess the efficacy of this new combination.

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Background and purpose: Primary and metastatic breast cancers still represent an unmet clinical need for improved chemotherapy and hormone therapy. Considerable attention has been paid to natural anticancer compounds, especially lignans. The study aimed to evaluate the activity of several lignans against breast cancer cells and assess the effect of leading lignans on signaling pathways in combination with metformin. Experimental approach: Human breast cancer cell lines MCF7 (hormone-dependent), MDA-MB-231, and SKBR3 (hormone-independent) were used. A hormone-resistant MCF7/hydroxytamoxifen (HT) subline was obtained by long-term cultivation of the MCF7 line with hydroxytamoxifen. Antiproliferative activity was assessed by the MTT test; the expression of signaling pathway proteins was evaluated by immunoblotting analysis. Findings/Results: We evaluated the antiproliferative activity of lignans in breast cancer cells with different levels of hormone dependence and determined the relevant IC50 values. Honokiol was chosen as the leading compound, and its IC50 ranged from 12 to 20 µM, whereas for other tested lignans, the IC50 exceeded 50 µM. The accumulation of cleaved PARP and a decrease in the expression of Bcl-2 and ERα in MCF7/HT were induced following the combination of honokiol with metformin. Conclusions and implications: Honokiol demonstrated significant antiproliferative activity against both hormone-dependent breast cancer cells and lines with primary and acquired hormone resistance. The combination of honokiol with metformin is considered an effective approach to induce death in hormone-resistant cells. Honokiol is of interest as a natural compound with antiproliferative activity against breast cancers, including resistant tumors.

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A convenient and selective approach to 13,17-secoestra-1,3,5(10)-trien-17-oic acid [N'-arylcarbothioamido]hydrazides and hybrid molecules containing secosteroid and 1,2,4-triazole fragments was disclosed and these novel types of secosteroids were screened for cytotoxicity against hormone-dependent human breast cancer cell line MCF-7. Most of secosteroid-1,2,4-triazole hybrids showed significant cytotoxic effect comparable or superior to that of the reference drug cisplatin. Hit secosteroid-1,2,4-triazole hybrids 4b and 4h were characterized by high cytotoxicity and good selectivity towards MCF-7 breast cancer cells. PARP cleavage (marker of apoptosis) and ERα and cyclin D1 downregulation were discovered in MCF-7 cells treated with lead secosteroid-1,2,4-triazole hybrid 4b. The synthesized secosteroids may be considered as new promising anticancer agents.

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Introduction: Resistance to chemotherapy and/or irradiation remains one of the key features of malignant tumors, which largely limits the efficiency of antitumor therapy. In this work, we studied the progression mechanism of breast cancer cell resistance to target drugs, including mTOR blockers, and in particular, we studied the exosome function in intercellular resistance transfer. Methods: The cell viability was assessed by the MTT assay, exosomes were purified by successive centrifugations, immunoblotting was used to evaluate protein expression, AP-1 activity was analyzed using reporter assay. Results: In experiments on the MCF-7 cell line (breast cancer) and the MCF-7/Rap subline that is resistant to rapamycin, the capability of resistant cell exosomes to trigger a similar rapamycin resistance in the parent MCF-7 cells was demonstrated. Exosome-induced resistance reproduces the changes revealed in MCF-7/Rap resistant cells, including the activation of ERK/AP-1 signaling, and it remains for a long time, for at least several months, after exosome withdrawal. We have shown that both the MCF-7 subline resistant to rapamycin and cells having exosome-triggered resistance demonstrate a stable decrease in the expression of DNMT3A, the key enzyme responsible for DNA methylation. Knockdown of DNMT3A in MCF-7 cells by siRNA leads to partial cell resistance to rapamycin; thus, the DNMT3A suppression is regarded as one of the necessary elements for the development of acquired rapamycin resistance. Conclusion: We propose that DNA demethylation followed by increased expression of key genes may be one of the factors responsible for the progression and maintenance of the resistant cell phenotype that includes exosome-induced resistance.

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OBJECTIVE: To develop, validate, and test the reproducibility of a new test capable of assessing functional performance in children and adolescents (PAY test: Performance Activity in Youth). METHODS: participants without and with asthma were included in the development and validation phases, respectively. The PAY test includes five activities: transition from sitting to standing, walking 10 m, step climbing, shoulder extension and flexion, and star jumps. Participants underwent the Pediatric Glittre test (TGlittre-P test time), modified shuttle test (MST), and cardiopulmonary exercise test (CPET). OUTCOMES: PAY test and TGlittre-P test times, oxygen uptake (VO2peak), and distance walked in the MST. RESULTS: 8 healthy volunteers, aged 12 (7 - 15) years old were included in the development phase and 34 participants with asthma, aged 11 (7 -14) years old, in the validation phase. The PAY test elicited greater physiological responses (VO2peak 33.5 ± 6.9 mL/kg) than the TGlittre-P (VO2peak: 27.4 ± 9.0 mL/kg), but lower than the MST (VO2peak: 48.9 ± 14.2 mL/kg) and CPET (VO2peak: 42.0 ± 8.8 mL/kg), p < .05. Moderate correlation between the PAY test time and the TGlittre-P time (r = 0.70, p < .001) and distance walked in the MST (r = -0.72, p < .001). The PAY test time was longer in participants with asthma than in healthy participants (3.1 [3.0 - 3.3] min vs. 2.3 [2.1 - 2.4 min]), p < .001.; and the test was reproducible (ICC 0.78, CI 95% 0.55-0.90, p < .001). CONCLUSIONS: The PAY test is a valid and reproducible tool for assessing functional performance in children and adolescents with asthma.

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Reconstructive and regenerative bone surgery is based on the use of high-tech biocompatible implants needed to restore the functions of the musculoskeletal system of patients. Ti6Al4V is one of the most widely used titanium alloys for a variety of applications where low density and excellent corrosion resistance are required, including biomechanical applications (implants and prostheses). Calcium silicate or wollastonite (CaSiO3) and calcium hydroxyapatite (HAp) is a bioceramic material used in biomedicine due to its bioactive properties, which can potentially be used for bone repair. In this regard, the research investigates the possibility of using spark plasma sintering technology to obtain new CaSiO3-HAp biocomposite ceramics reinforced with a Ti6Al4V titanium alloy matrix obtained by additive manufacturing. The phase and elemental compositions, structure, and morphology of the initial CaSiO3-HAp powder and its ceramic metal biocomposite were studied by X-ray fluorescence, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Brunauer-Emmett-Teller analysis methods. The spark plasma sintering technology was shown to be efficient for the consolidation of CaSiO3-HAp powder in volume with a Ti6Al4V reinforcing matrix to obtain a ceramic metal biocomposite of an integral form. Vickers microhardness values were determined for the alloy and bioceramics (~500 and 560 HV, respectively), as well as for their interface area (~640 HV). An assessment of the critical stress intensity factor KIc (crack resistance) was performed. The research result is new and represents a prospect for the creation of high-tech implant products for regenerative bone surgery.

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Purpose: Secondary acquired lacrimal duct obstruction (SALDO) is one of the complications of radioiodine therapy. SALDO is formed a few months after therapy if there is a sufficient uptake of radioactive iodine by the nasolacrimal duct. To date, risk factors leading to SALDO are unclear. The objective was to determine the correlation between the tear production level and radioactive iodine-131 uptake in the lacrimal ducts. Methods: Basal and reflex tear production was studied in 64 eyes prior to the therapy with radioactive iodine-131 after drug-induced hypothyroidism. The condition of the ocular surface was assessed using the Ocular Surface Disease Index (OSDI) questionnaire. Seventy-two hours after the radioactive iodine therapy, scintigraphy was performed, which determined the presence or absence of iodine-131 in the lacrimal ducts. T-statistics and the Mann-Whitney criterion were used to identify the differences between the groups. The differences were considered significant at P ≤ 0.05. The current tear production level in patients receiving radioiodine therapy was determined using a mathematical model. Results: A statistically significant difference between the basal (p = 0.044) and reflex (p = 0.015) tear production levels was found in cases with and without iodine-131 uptake by the lacrimal ducts. The probable current tear production level corresponds to the sum of basal and 10-20% of reflex tear production. The uptake of iodine-131 was found regardless of the OSDI results. Conclusion: The probability of iodine-131 uptake by the lacrimal ducts rises as the tear production level increases.

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Aim: The study aims to analyze the effect of long-term incubation of ERα-positive MCF7 breast cancer cells with 4-hydroxytamoxifen (HT) on their sensitivity to tubulin polymerization inhibitor docetaxel. Methods: The analysis of cell viability was performed by the MTT method. The expression of signaling proteins was analyzed by immunoblotting and flow cytometry. ERα activity was evaluated by gene reporter assay. To establish hormone-resistant subline MCF7, breast cancer cells were treated with 4-hydroxytamoxifen for 12 months. Results: The developed MCF7/HT subline has lost sensitivity to 4-hydroxytamoxifen, and the resistance index was 2. Increased Akt activity (2.2-fold) and decreased ERα expression (1.5-fold) were revealed in MCF7/HT cells. The activity of the estrogen receptor α was reduced (1.5-fold) in MCF7/HT. Evaluation of class III ß-tubulin expression (TUBB3), a marker associated with metastasis, revealed the following trends: higher expression of TUBB3 was detected in triple-negative breast cancer MDA-MB-231 cells compared to hormone-responsive MCF7 cells (P < 0.05). The lowest expression of TUBB3 was found in hormone-resistant MCF7/HT cells (MCF7/HT < MCF7 < MDA-MB-231, approximately 1:2:4). High TUBB3 expression strongly correlated with docetaxel resistance: IC50 value of docetaxel for MDA-MB-231 cells was greater than that for MCF7 cells, whereas resistant MCF7/HT cells were the most sensitive to the drug. The accumulation of cleaved PARP (a 1.6-fold increase) and Bcl-2 downregulation (1.8-fold) were more pronounced in docetaxel-treated resistant cells (P < 0.05). The expression of cyclin D1 decreased (2.8-fold) only in resistant cells after 4 nM docetaxel treatment, while this marker was unchanged in parental MCF7 breast cancer cells. Conclusion: Further development of taxane-based chemotherapy for hormone-resistant cancer looks highly promising, especially for cancers with low TUBB3 expression.

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Abstract This study aimed to investigate the activities of novel 20(R)-3,20-dihydroxy-19-norpregn-1,3,5(10)-trienes (kuz7 and kuz8b) of natural 13ß- and epimeric 13α-series against triple-negative MDA-MB-231 breast cancer cells. High antiproliferative activity of synthesized compounds kuz8b and kuz7 against MDA-MB-231 triple-negative cancer cells was revealed. The steroid kuz7 of natural 13ß-configuration was more active against MDA-MB-231 cells than the 13α-steroid kuz8b. Cell cycle analysis revealed common patterns for the action of both tested compounds. The number of cells in the subG1 phase increased in a dose-dependent manner, indicating induction of apoptosis, which was also verified by PARP cleavage. In contrast, the number of cells in the G0/G1 phase decreases with increasing compound concentration. Steroid kuz7 at micromolar concentrations reduced the expression of GLUT1, a glucose transporter. High efficacy of the combination of kuz7 with biguanide metformin was shown, and synergistic effects on MDA-MB-231 cell growth and expression of the anti-apoptotic protein Bcl-2 were revealed. According to the obtained results, including the high activity of kuz7 against triple-negative cancer cells, the detected induction of apoptosis, and the decrease in GLUT1 expression, 13ß-steroid kuz7 is of interest for further preclinical studies both alone and in combination with the metabolic drug metformin

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Abstract Objective: To develop, validate, and test the reproducibility of a new test capable of assessing functional performance in children and adolescents (PAY test: Performance Activity in Youth). Methods: participants without and with asthma were included in the development and validation phases, respectively. The PAY test includes five activities: transition from sitting to standing, walking 10 m, step climbing, shoulder extension and flexion, and star jumps. Participants underwent the Pediatric Glittre test (TGlittre-P test time), modified shuttle test (MST), and cardiopulmonary exercise test (CPET). Outcomes: PAY test and TGlittre-P test times, oxygen uptake (VO2peak), and distance walked in the MST. Results: 8 healthy volunteers, aged 12 (7 -15) years old were included in the development phase and 34 participants with asthma, aged 11 (7-14) years old, in the validation phase. The PAY test elicited greater physiological responses (VO2peak 33.5 ± 6.9 mL/kg) than the TGlittre-P (VO2peak: 27.4 ± 9.0 mL/kg), but lower than the MST (VO2peak: 48.9 ± 14.2 mL/kg) and CPET (VO2peak: 42.0 ± 8.8 mL/kg), p < .05. Moderate correlation between the PAY test time and the TGlittre-P time (r = 0.70, p < .001) and distance walked in the MST (r = -0.72, p < .001). The PAY test time was longer in participants with asthma than in healthy participants (3.1 [3.0 - 3.3] min vs. 2.3 [2.1 - 2.4 min]), p < .001.; and the test was reproducible (ICC 0.78, CI 95% 0.55-0.90, p < .001). Conclusions: The PAY test is a valid and reproducible tool for assessing functional performance in children and adolescents with asthma.

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(1) Background: This investigation aimed at developing a series of c-Met-targeting cabozantinib-based PROTACs. (2) Methods: Purification of intermediate and target compounds was performed using column chromatography, in vitro antiproliferation activity was measured using a standard MTT assay and a c-Met degradation assay was performed via the immunoblotting technique. (3) Results: Several compounds exhibited antiproliferative activity towards different cell lines of breast cancer (T47D, MDA-MB-231, SKBR3, HCC1954 and MCF7) at the same level as parent cabozantinib and 7-demethyl cabozantinib. Two target conjugates, bearing a VHL-ligand as an E3-ligase binding moiety and glycol-based linkers, exhibited the effective inhibition of c-Met phosphorylation and an ability to decrease the level of c-Met in HCC1954 cells at micromolar concentrations. (4) Conclusions: Two compounds exhibit c-Met inhibition activity in the nanomolar range and can be considered as PROTAC molecules due to their ability to decrease the total level of c-Met in HCC1954 cells. The structures of the offered compounds can be used as starting points for further evaluation of cabozantinib-based PROTACs.

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Xanthine derivatives have been a great area of interest for the development of potent bioactive agents. Thirty-eight methylxanthine derivatives as acetylcholinesterase inhibitors (AChE) were designed and synthesized. Suzuki-Miyaura cross-coupling reactions of 8-chlorocaffeine with aryl(hetaryl)boronic acids, the CuAAC reaction of 8-ethynylcaffeine with several azides, and the copper(I) catalyzed one-pot three-component reaction (A3-coupling) of 8-ethynylcaffeine, 1-(prop-2-ynyl)-, or 7-(prop-2-ynyl)-dimethylxanthines with formaldehyde and secondary amines were the main approaches for the synthesis of substituted methylxanthine derivatives (yield 53-96%). The bioactivity of all new compounds was evaluated by Ellman's method, and the results showed that most of the synthesized compounds displayed good and moderate acetylcholinesterase (AChE) inhibitory activities in vitro. The structure-activity relationships were also discussed. The data revealed that compounds 53, 59, 65, 66, and 69 exhibited the most potent inhibitory activity against AChE with IC50 of 0.25, 0.552, 0.089, 0.746, and 0.121 µM, respectively. The binding conformation and simultaneous interaction modes were further clarified by molecular docking studies.

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The overexpression and activity of carbonic anhydrase (CA, EC 4.2.1.1) isoforms CA IX and CA XII promote the accumulation of exceeding protons and acidosis in the extracellular tumor environment. Sulfonamides are effective inhibitors of most families of CAs. In this study, using scaffold-hopping, indoline-5-sulfonamide analogs 4a-u of the CA IX-selective inhibitor 3 were designed and synthesized to evaluate their biological properties. 1-Acylated indoline-5-sulfonamides demonstrated inhibitory activity against tumor-associated CA IX and XII with KI values up to 132.8 nM and 41.3 nM. Compound 4f, as one of the most potent inhibitors of CA IX and XII, exhibits hypoxic selectivity, suppressing the growth of MCF7 cells at 12.9 µM, and causes partial inhibition of hypoxia-induced CA IX expression in A431 skin cancer cells. 4e and 4f reverse chemoresistance to doxorubicin of K562/4 with overexpression of P-gp.

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Synthesis of 21,22-cyclosteroids has been achieved starting from pregnenolone acetate. The key transformation was the Kulinkovich reaction of 17-vinyl steroids with esters. The resulting cyclopropanols were further subjected to three-membered ring-opening under various conditions including to base-, palladium or visible light-promoted isomerization and cross-coupling reaction. A number of steroidal Δ2-6-ketones and 3ß-hydroxy-Δ5-enes with functional groups at C-21 - C-23 have been synthesized via the 21,22-cyclosteroids. The antiproliferative and antihormonal activity of the obtained compounds on the cell lines of prostate (22Rv1) and breast (MCF-7) cancer was studied. The androgen receptor activity was assessed by reporter assay when the expression of signalling proteins was evaluated by immunoblotting. (20S,22R)-22-Acetoxy-21,22-cyclo-5α-cholest-5-ene with the moderate antiandrogenic potency revealed IC50 values of 18.4 ± 1.2 and 14.6 ± 1.4 µM against MCF-7 and 22Rv1 cells, respectively, and its effects on the expression of AR-V7, cyclin D1 and BCL2 were explored.

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A (series) range of potential dimorpholinoquinazoline-based inhibitors of the PI3K/Akt/mTOR cascade was synthesized. Several compounds exhibited cytotoxicity towards a panel of cancer cell lines in the low and sub-micromolar range. Compound 7c with the highest activity and moderate selectivity towards MCF7 cells which express the mutant type of PI3K was also tested for the ability to inhibit PI3K-(signaling pathway) downstream effectors and associated proteins. Compound 7c inhibited the phosphorylation of Akt, mTOR, and S6K at 125-250 nM. It also triggered PARP1 cleavage, ROS production, and cell death via several mechanisms. Inhibition of PI3Kα was observed at a concentration of 7b 50 µM and of 7c 500 µM and higher, that can indicate minority PI3Kα as a target among other kinases in the titled cascade for 7c. In vivo studies demonstrated an inhibition of tumor growth in the colorectal tumor model. According to the docking studies, the replacement of the triazine core in gedatolisib (8) by a quinazoline fragment, and incorporation of a (hetero)aromatic unit connected with the carbamide group via a flexible spacer, can result in more selective inhibition of the PI3Kα isoform.

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The occurrence and the style of volcanic eruptions are largely controlled by the ways in which magma is stored and transported from the mantle to the surface through the crust. Nevertheless, our understanding of the deep roots of volcano-magmatic systems remains very limited. Here, we use the sources of seismovolcanic tremor to delineate the active part of the magmatic system beneath the Klyuchevskoy Volcanic Group in Kamchatka, Russia. The tremor sources are distributed in a wide spatial region over the whole range of crustal depths connecting different volcanoes of the group. The tremor activity is characterized by rapid vertical and lateral migrations explained by fast pressure transients and dynamic permeability. Our results support the conceptual model of extended and highly dynamic trans-crustal magmatic systems.