Novel triterpenoid pyrones, phthalimides and phthalates are selectively cytotoxic in CCRF-CEM cancer cells - Synthesis, potency, and mitochondrial mechanism of action

A series of triterpenoid pyrones was synthesized and subsequently modified to introduce phthalimide or phthalate moieties into the triterpenoid skeleton. These compounds underwent in vitro cytotoxicity screening, revealing that a subset of six compounds exhibited potent activity, with IC50 values in the low micromolar range. Further biological evaluations, including Annexin V and propidium iodide staining experiment revealed, that all compounds induce selective apoptosis in cancer cells. Measurements of mitochondrial potential, cell cycle analysis, and the expression of pro- and anti-apoptotic proteins confirmed, that apoptosis was mediated via the mitochondrial pathway. These findings were further supported by cell cycle modulation and DNA/RNA synthesis studies, which indicated a significant increase in cell accumulation in the G0/G1 phase and a marked reduction in S-phase cells, alongside a substantial inhibition of DNA synthesis. The activation of caspase-3 and the cleavage of PARP, coupled with a decrease in the expression of Bcl-2 and Bcl-XL proteins, underscored the induction of apoptosis through the mitochondrial pathway. Given their high activity and pronounced effect on mitochondria function, trifluoromethyl pyrones 1f and 2f, and dihydrophthalimide 2h have been selected for further development.

Measurement of polarization observables T, P, and H in π0 and η photoproduction off quasi-free nucleons

The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π 0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γ p → π 0 p and γ p → η p reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the η n system at W = 1.68 GeV . A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S 11 ( 1535 ) and S 11 ( 1650 ) resonances within the S 11 -partial wave.

[Pathological Lesions and Fractures of the Proximal Femur]

PURPOSE OF THE STUDY The aim of the study was to determine the incidence of primary malignancies metastasizing to the area of the proximal femur, to evaluate the localization of the lesions and fractures, to compare the results of the selected surgical therapy, survival time of the patients and postoperative complications. MATERIAL AND METHODS We retrospectively evaluated the group of patients operated on from 2012 to 2021. The study included 45 patients (24 women and 21 men) with a pathological lesion or a pathological fracture in the area of the proximal femur. The average age was 67 years (38-90). There were 30 (67%) cases of pathological fracture and 15 (33%) cases of pathological lesions in the cohort. In each patient, the perioperative biopsy or resected sample was sent for histological examination. The type of primary malignancy with the localization of lesions and fractures was assessed. Furthermore, we evaluated the outcomes of the surgical method chosen and its complications. We monitored the patients' functional score using the Karnofsky performance status and survival interval. RESULTS The most common primary malignancy was multiple myeloma in 10 cases (22%), followed by seven cases (16%) of breast and lung cancer and 6 cases (13%) of clear cell renal cell carcinoma. Internal fixation was used in 15 cases (33%). Tumor resection with hip joint replacement was performed in 29 patients (64%). One patient was treated with percutaneous femoroplasty. Out of a total of 45 patients, 10 patients (22%) survived for less than three months. The survival rate of more than one year was observed in 21 patients (47%). A total of seven complications occurred in six patients (15%). Fewer complications occurred in the group of patients with a pathological fracture compared to the group with an impending fracture. DISCUSSION Pathological lesions in the bone or an already existing pathological fracture are signs of advanced cancer. Better outcomes are reported in patients who underwent prophylactic surgery, which was, however, not confirmed by our study. The incidence of individual primary malignancies, the postoperative complications and the patient survival corresponded to the statistical data reported by the other authors. CONCLUSIONS In patients with a pathological lesion of the proximal femur, operative treatment will increase the quality of life, either when choosing osteosynthesis or joint replacement, while prophylactic treatment is usually associated with a better prognosis. As a less invasive procedure with lower blood loss, osteosynthesis is indicated for palliative therapy in patients with a limited expected survival time or in patients with a prognosis of healing of the lesion. Reconstruction of the joint with an arthroplasty is indicated in patients with a better prognosis or in cases excluding safe osteosynthesis. Our study confirmed good outcomes with the use of an uncemented revision femoral component. Key words: metastasis, osteolysis, pathological fracture, proximal femur.

Triterpenoid pyrazines and pyridines - Synthesis, cytotoxicity, mechanism of action, preparation of prodrugs

A set of fifteen triterpenoid pyrazines and pyridines was prepared from parent triterpenoid 3-oxoderivatives (betulonic acid, dihydrobetulonic acid, oleanonic acid, moronic acid, ursonic acid, heterobetulonic acid, and allobetulone). Cytotoxicity of all compounds was tested in eight cancer and two non-cancer cell lines. Evaluation of the structure-activity relationships revealed that the triterpenoid core determined whether the final molecule is active or not, while the heterocycle is able to increase the activity and modulate the specificity. Five compounds (1b, 1c, 2b, 2c, and 8) were found to be preferentially and highly cytotoxic (IC₅₀ ≈ 1 μM) against leukemic cancer cell lines (CCRF-CEM, K562, CEM-DNR, or K562-TAX). Surprisingly, compounds 1c, 2b, and 2c are 10-fold more active in multidrug-resistant leukemia cells (CEM-DNR and K562-TAX) than in their non-resistant analogs (CCRF-CEM and K562). Pharmacological parameters were measured for the most promising candidates and two types of prodrugs were synthesized: 1) Sugar-containing conjugates, most of which had improved cell penetration and retained high cytotoxicity in the CCRF-CEM cell line, unfortunately, they lost the selectivity against resistant cells. 2) Medoxomil derivatives, among which compounds 26-28 gained activities of IC₅₀ 0.026-0.043 μM against K562 cells. Compounds 1b, 8, 21, 22, 23, and 24 were selected for the evaluation of the mechanism of action based on their highest cytotoxicity against CCRF-CEM cell line. Several experiments showed that the majority of them cause apoptosis via the mitochondrial pathway. Compounds 1b, 8, and 21 inhibit growth and disintegrate spheroid cultures of HCT116 and HeLa cells, which would be important for the treatment of solid tumors. In summary, compounds 1b, 1c, 2b, 2c, 24, and 26-28 are highly and selectively cytotoxic against cancer cell lines and were selected for future in vivo tests and further development of anticancer drugs.

Abstract 1530: Derivatives of betulinic acid act as modulators of the androgen receptor and report cytotoxicity towards cancer cell lines

INTRODUCTION Triterpenoids are naturally occurring substances with a broad spectrum of beneficial effects for human health. Betulinic acid belongs to the group of pentacyclic triterpenoids and is well known for its antitumor activities. The library of about 1000 betulinic acid-derived triterpenes was collected and analyzed for cytotoxic activity on cancer and non-cancer cell lines (A549, CCRF-CEM, CEM-DNR, HCT116, K562, K562-TAX, U2OS, BJ and MRC-5) in our Institute over the last 20 years. Steroidal triterpenes are precursors of cholesterol, the precursor of testosterone, the fundamental ligand of the androgen receptor that is the key regulator in several physiological and pathological processes. Finding new modulators of androgen receptor is critical for the treatment of various androgen-dependent diseases, including prostate cancer or anabolic deficiencies. Betulinic acid and its derivatives showed structural similarity with steroids and therefore were selected to be tested for androgen receptor activity modulation.

METHODS The stably transfected cell line HEK 293T GFP-AR was used to determine the translocation activity of the androgen receptor from the cytoplasm to the nucleus after the treatment with the derivatives. The high throughput fluorescent microscopy device and image analysis comprised the data, and compounds with the proved activity were selected for subsequent analysis. The luciferase reporter gene assay was further used to evaluate the effect of compounds on the transcriptional activity of the androgen receptor. The MTS assay was performed to assess the cytotoxicity.

RESULTS Betulinic acid and its eight derivatives were identified to have 5-6 - fold higher translocation activity of AR (ratio cytoplasm GFP intensity/nuclear GFP intensity) than the negative control. Validation on luminescence luciferase reporter assay confirmed 4-5 - fold induction for five derivatives, whereas three derivatives were not active. Interestingly only two of them showed substantial cytotoxicities (IC50< 50 µM) as they possess significant inhibitory activity against all tested cancer cell lines with favorable therapeutic index against the non-cancer cell lines.

CONCLUSION Derivatives of betulinic acid were proven to have modulatory activity on the androgen receptor pathway. The two derivatives of betulinic acid also displayed cytotoxicity towards almost all of the tested cancer cell lines. There could be not only AR modulation responsible for anticancer activity as the derivatives of betulinic acid are well know disruptors of mitochondrion functions as well. The synergy of these two mechanisms of action could potentiate the antitumor activity of the selected compounds.

This work was supported by ENOCH CZ.02.1.01/0.0/0.0/16_019/0000868, CZ-OPENSCREEN - LM2018130, EATRIS-CZ - LM2018133.

Citation Format: Alzbeta Srovnalova, Sona Gurska, Milan Urban, Jan Sarek, Jiri Rehulka, Petr Dzubak, Marian Hajduch. Derivatives of betulinic acid act as modulators of the androgen receptor and report cytotoxicity towards cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1530.

Making a difference in the real world. User-centred impact evaluation of an eight-country, community-based early childhood programme

This paper presents a unique approach to the Impact Evaluation of a project that focused on low-threshold intergenerational play-based interactions in order to support young children from marginalised communities in eight European countries. The approach builds upon the work of Fetterman's Empowerment Evaluation and Patton's Utilization Focused Evaluation and brings them together to form an adapted model of evaluation. We outline in this paper how these two well developed methods of evaluation have been applied to a real world context, that is, the impact evaluation of a complex international project. Our approach highlights the complexities of differing contexts and allows for surprising and unintended consequences to emerge. It results, through double loop learning, a type of feedback loop with the internal stakeholders and implementers that is useful to the project coordination team, with a view to further upscaling of the initiative. Recommendations for policy at local, national and European Union levels were provided to the project and potential external users. However, the predominant feedback was provided at two crucial points along the way; during a stakeholder mapping exercise and during the further development of monitoring data tools.

Substituted dienes prepared from betulinic acid - Synthesis, cytotoxicity, mechanism of action, and pharmacological parameters

A set of new substituted dienes were synthesized from betulinic acid by its oxidation to 30-oxobetulinic acid followed by the Wittig reaction. Cytotoxicity of all compounds was tested in vitro in eight cancer cell lines and two noncancer fibroblasts. Almost all dienes were more cytotoxic than betulinic acid. Compounds 4.22, 4.30, 4.33, 4.39 had IC₅₀ below 5 μmol/L; 4.22 and 4.39 were selected for studies of the mechanism of action. Cell cycle analysis revealed an increase in the number of apoptotic cells at 5 × IC₅₀ concentration, where activation of irreversible changes leading to cell death can be expected. Both 4.22 and 4.39 led to the accumulation of cells in the G0/G1 phase with partial inhibition of DNA/RNA synthesis at 1 × IC₅₀ and almost complete inhibition at 5 × IC₅₀. Interestingly, compound 4.39 at 5 × IC₅₀ caused the accumulation of cells in the S phase. Higher concentrations of tested drugs probably inhibit more off-targets than lower concentrations. Mechanisms disrupting cellular metabolism can induce the accumulation of cells in the S phase. Both compounds 4.22 and 4.39 trigger selective apoptosis in cancer cells via intrinsic pathway, which we have demonstrated by changes in the expression of the crucial apoptosis-related protein. Pharmacological parameters of derivative 4.22 were superior to 4.39, therefore 4.22 was the finally selected candidate for the development of anticancer drug.

[Validation of a French version of the 16-item Prodromal Questionnaire (fPQ16) in adolescents and young adults seeking help]

INTRODUCTION

The duration of untreated psychosis has been largely associated with poor outcomes in psychosis. Actual diagnostic tools may be used by very specialized teams and need sustained evaluation. We present a French version of a self-report questionnaire: the 16-item Prodromal Questionnaire (fPQ16). Our objective was to evaluate its predictive value for an ultra-high-risk state (UHR) or psychosis. The population enrolled was consulting in a young adults and adolescents center in Sainte-Anne hospital, Paris, France.

METHODS

PQ16 had first been translated into French and independently back translated and validated by the original authors. Between November 2016 and May 2018, every C'JAAD consulting patient was proposed to fill in the fPQ16. Each patient was next evaluated with the French version of the comprehensive assessment of at-risk mental state (CAARMS), which detects UHR or psychosis. Statistical analysis of fPQ16 concurrent validity was performed using ROC curves. fPQ16 acceptability was studied by four additional questions especially designed for that purpose.

RESULTS

One hundred participants were included. Mean age was 19.85years (SD 3.3 y). Fifty-eight percent of patients included were diagnosed with UHR (40%) or psychotic (18%) state after CAARMS evaluation. Mean score at fPQ16 was 5.7 (SD 3.8). Best cut-off score was 4 positive items, with excellent sensibility (91%) and correct specificity (60%). Positive predictive value of fPQ16 was 76%. Area under the curve was 0.85 (P<0.0001). fPQ16 showed good acceptability.

DISCUSSION

fPQ16 had good screening performances in our population. Cut-off score was lower than in previous studies, but performances were equal or better. As a well-accepted and short questionnaire, the fPQ16 could be a great screening tool in primary care. A version with 18-items, including two items focused on thought content and disorganization that are missing in PQ16, is under evaluation.

Biocatalysis in the Chemistry of Lupane Triterpenoids

Pentacyclic triterpenes are important representatives of natural products that exhibit a wide variety of biological activities. These activities suggest that these compounds may represent potential medicines for the treatment of cancer and viral, bacterial, or protozoal infections. Naturally occurring triterpenes usually have several drawbacks, such as limited activity and insufficient solubility and bioavailability; therefore, they need to be modified to obtain compounds suitable for drug development. Modifications can be achieved either by methods of standard organic synthesis or with the use of biocatalysts, such as enzymes or enzyme systems within living organisms. In most cases, these modifications result in the preparation of esters, amides, saponins, or sugar conjugates. Notably, while standard organic synthesis has been heavily used and developed, the use of the latter methodology has been rather limited, but it appears that biocatalysis has recently sparked considerably wider interest within the scientific community. Among triterpenes, derivatives of lupane play important roles. This review therefore summarizes the natural occurrence and sources of lupane triterpenoids, their biosynthesis, and semisynthetic methods that may be used for the production of betulinic acid from abundant and inexpensive betulin. Most importantly, this article compares chemical transformations of lupane triterpenoids with analogous reactions performed by biocatalysts and highlights a large space for the future development of biocatalysis in this field. The results of this study may serve as a summary of the current state of research and demonstrate the potential of the method in future applications.

Measurement of the helicity asymmetry E for the reaction γ p → π 0 p : The CBELSA/TAPS Collaboration

A measurement of the double-polarization observable E for the reaction γ p → π 0 p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C4 H9 OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range fromE γ = 600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

Novel pentacyclic triterpenes exhibiting strong neuroprotective activity in SH-SY5Y cells in salsolinol- and glutamate-induced neurodegeneration models

Novel triterpene derivatives were prepared and evaluated in salsolinol (SAL)- and glutamate (Glu)-induced models of neurodegeneration in neuron-like SH-SY5Y cells. Among the tested compounds, betulin triazole 4 bearing a tetraacetyl-β-d-glucose substituent showed a highly potent neuroprotective effect. Further studies revealed that removal of tetraacetyl-β-d-glucose part (free triazole derivative 10) resulted in strong neuroprotection in the SAL model at 1 μM, but this derivative suffered from cytotoxicity at higher concentrations. Both compounds modulated oxidative stress and caspase-3,7 activity, but 10 showed a superior effect comparable to the Ac-DEVD-CHO inhibitor. Interestingly, while both 4 and 10 outperformed the positive controls in blocking mitochondrial permeability transition pore opening, only 4 demonstrated potent restoration of the mitochondrial membrane potential (MMP) in the model. Derivatives 4 and 10 also showed neuroprotection in the Glu model, with 10 exhibiting the strongest oxidative stress reducing effect among the tested compounds, while the neuroprotective activity of 4 was probably due recovery of the MMP.

Observation of the pη^{'} Cusp in the New Precise Beam Asymmetry Σ Data for γp→pη

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748  MeV to W=2045  MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447  MeV (W=1896  MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

Squaric acid analogues in medicinal chemistry

In this review, we summarize the published data on squaric acid analogues with a special focus on their use in medicinal chemistry and as potential drugs. Squaric acid is an interesting small molecule with an almost perfectly square shape, and its analogues have a variety of biological activities that are enabled by the presence of significant H-bond donors and acceptors. Unfortunately, most of these compounds also exhibit reactive functionalities, and this deters the majority of medicinal chemists and pharmacologists from trying to use them in drug development. However, this group of compounds is experiencing a renaissance, and large numbers of them are being tested for antiprotozoal, antibacterial, antifungal, and antiviral activities. The most useful of these compounds exhibited IC₅₀ values in the nanomolar range, which makes them promising drug candidates. In addition to these activities, their interactions with living systems were intensively explored, revealing that squaric acid analogues inhibit various enzymes and often serve as receptor antagonists and that the squaric acid moiety may be used as a non-classical isosteric replacement for other functional groups such as carboxylate. In summary, this review is focused on squaric acid and its analogues and their use in medicinal chemistry and should serve as a guide for other researchers in the field to demonstrate the potential of these compounds based on previous research.

Features of the Energy Spectrum of Cosmic Rays above 2.5×10^{18} eV Using the Pierre Auger Observatory

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18}  eV based on 215 030 events. New results are presented: at about 1.3×10^{19}  eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19}  eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18}  eV is [5.66±0.03(stat)±1.40(syst)]×10^{53}  erg Mpc^{-3}.