Еvaluation of antitumor activity of some 4-aminopiperidine derivatives — low molecular weight Hsp70 inhibitors — on transplantable mouse tumors

Low molecular weight compounds targeting chaperone proteins Hsp90 and Hsp70 have opened up a new avenue in the therapy of neoplasms. In 2020, we tested 3 Hsp70 inhibitors from the class of 4-aminopiperidine derivatives for their antitumor activity on in vivo models. The list of the tested compounds included N-(2-chlorobenzyl)-N-ethyl-1-(2-(methylthio)pyrimidin-4-yl)piperidin-4-amine (compound 1), 4-((methyl(1-(2-(methylthio)pyrimidin-4-yl) piperidin-4-yl)amino)methyl) benzonitrile (compound 2) and N-(2,6- dichlorobenzyl)-1-(1-(2-(ethylthio)pyrimidin-4-yl)piperidin-4-yl)-N-methylmethaneamine (compound 3). The aim of this study was to compare the efficacy of 4-aminopiperidine derivatives in vivo using the models of transplantable murine L1210 lymphocytic leukemia and B16 melanoma. Compounds 2 and 3 used in combination with cyclophosphamide exhibited high cytotoxic activity (р = 0.05) against L1210 leukemia (an 80-82% increase in survival time) and B16 melanoma (98-99.7% tumor growth delay). For L1210 lymphocytic leukemia, compounds 2 and 3 used in combination with cyclophosphamide fell into the low (+) therapeutic potential category. For B16 melanoma, compounds 1, 2 and 3 used in combination with cyclophosphamide fell into either low (+) or moderate (++) therapeutic potential categories. On the whole, the tested doses of the compounds used in combination with cyclophosphamide hold promise for the therapy of L1210 leukemia and B16 melanoma in mouse models. Our findings confirm the potential of low molecular weight Hsp70 inhibitors for combination chemotherapy against cancer.

Khasiat dan Profil Kromatogram Fraksi Aktif dari Ekstrak Kulit Buah Manggis (Garcinia mangostana L.) yang Diiradiasi

The mangosteen fruit peel (Garcinia mangostana L.) are used as anti-infl ammatory, antihistamine, treatment of heart disease, antibacterial, antifungal, it is also used for the treatment or therapy of cancer, because it has a cytotoxic activity against cancer cells. Most of Indonesian people have used the mangosteen fruit peel and they produce mangosteen peel into powder or herbal medicine industry has produced its extract in capsules. Efforts to preserve dried mangosteen rind has done by heating process or by gamma irradiation technique. This study aimed to study the effect of gamma irradiation on cytotoxicity activity of extracts and active fractions mangosteen fruit peel against L1210 leukemia cells and chromatogram profi le of extracts and active fractions of the mangosteen fruit peel. Dry powder mangosteen rind irradiated using gamma irradiation dose of 5; 7.5; 10; and 15 kGy. Then each sample was successive macerated in n-hexane, ethyl acetate, and ethanol. Each extract was tested cytotoxicity against L1210 leukemia cells. The ethyl acetate extract was most active extract (IC50 = 4.17 mg/mL) compared with n-hexane extract (IC50 = 8.29 mg/mL) and ethanol extract (IC50 = 7.52 mg/mL). Fractionation of ethyl acetate extract by column chromatography were obtained 6 fractions. The result of cytotoxicity test showed that fraction 1 was the most active fraction (IC50 = 3.97 mg/mL), it was it was still categorized as potential anticancer (IC50 ≤ 20 mg/mL). Profi le chromatogram of fraction 1 with TLC-densitometry showed patches of discoloration on irradiation dose of 10 and 15 kGy. The results of analysis by HPLC fraction 1 showed a decrease of peak area at a dose of 10 kGy was signifi cantly different from the control. Based on the chromatogram profi le of fraction 1 and itscytotoxicity against L1210 leukemia cells, so the maximum dose of 7.5 kGy gamma irradiation can beap plied on irradiation of mangosteen fruit peel without changing its effi cacy as anti-cancer agent.

GREEN TEA, RED WINE AND LEMON EXTRACTS REDUCE EXPERIMENTAL TUMOR GROWTH AND CANCER DRUG TOXICITY

Aim: To evaluate antitumor effect of plant polyphenol extracts from green tea, red wine lees and/or lemon peel alone and in combination with antitumor drugs on the growth of different transplanted tumors in experimental animals. Materials and Methods: Green tea extract (GTE) was prepared from green tea infusion. GTE-based composites of red wine (GTRW), lemon peel (GTRWL) and/ or NanoGTE as well as corresponding nanocomposites were prepared. The total polyphenolics of the different GTE-based extracts ranged from 18.0% to 21.3%. The effects of GTE-based extracts were studied in sarcoma 180, Ehrlich carcinoma, B16 melanoma, Ca755 mammary carcinoma, P388 leukemia, L1210 leukemia, and Guerin carcinoma (original, cisplatin-resistant and doxorubicinresistant variants). The extracts were administered as 0.1% solution in drinking water (0.6–1.0 mg by total polyphenolics per mouse per day and 4.0–6.3 mg per rat per day). Results: Tumor growth inhibition (TGI) in mice treated with NanoGTE, cisplatin or cisplatin + NanoGTE was 27%, 55% and 78%, respectively, in Sarcoma 180%, 21%, 45% and 59%, respectively, in Ehrlich carcinoma; and 8%, 13% and 38%, respectively in B16 melanoma. Composites of NanoGTE, red wine, and lemon peel (NanoGTRWL) enhanced the antitumor effects of cyclophosphamide in mice with Ca755 mammary carcinoma. The treatment with combination of NanoGTE and inhibitors of polyamines (PA) synthesis (DFMO + MGBG) resulted in significant TGI of P388 leukemia (up to 71%) and L1210 leukemia. In rats transplanted with Guerin carcinoma (parental strain), treatment with GTRW or GTE alone resulted in 25– 28% TGI vs. 55–68% TGI in cisplatin-treated animals. The inhibition observed in the case of combination of GTE or GTRW with cisplatin was additive giving 81–88% TGI. Similar effects were observed when combinations of the cytostatics with GTE (or N anoGTE) were tested against cisplatin- or doxorubicin-resistant Guerin carcinoma. Moreover, the plant extracts lowered side toxicity of the drugs. Treatment with GTE, NanoGTE, and NanoGTRW decreased the levels of malondialdehyde in heart, kidney and liver tissue of experimental animals, as well as the levels of urea and creatinine in blood serum, increased erythrocyte and platelet counts, hemoglobin content, and decreased leucocyte counts. Conclusion: The obtained data indicate the prospects for further deve lopment of GTE and corresponding nanocomposites as auxiliary agents in cancer chemotherapy.

PHARMACOLOGICAL EFFECT OF AMINOFERROCENE IN MICE WITH L1210 LEUKEMIA

Aim: To study the cytostatic and some biological effects of aminoferrocene using mice with L1210 lymphoid leukemia. Materials and Methods: Experiments were performed on BDF1 male mice (DBA/2, female × C57Bl/6, male) with transplantable L1210 lymphoid leukemia. Determination of antitumor activity of Benzyl-Fc Boron (Bn), it was injected intraperitoneally 6 times daily, starting on day 2 after L1210 leukemia cell transplantation. Doses of Bn such as 26; 260 and 2600 μg/kg were used. The determination of intracellular content of cardiolipin, thiols, reactive oxygen species (ROS) and also analysis of Annexin V positivity and mitochondrial transmembrane potential (JC-1 staining) were performed with use of flow cytometry. The levels of “free iron” complexes, transferrin active forms and the rate of NO generation were measured by EPR-specroscopy. Results: Six daily injections of Bn at a dose of 26 μg/kg resulted in an increased survival of mice with L1210 leukemia by 28% (p < 0.05). Bn led to an increase of apoptotic cells number and ROS amount in leukemia cells. Besides, Bn caused a decrease of cardiolipin and nonprotein thiol compounds content. The membrane electrochemical potential of cell mitochondria was decreased also after Bn administration. Studies using EPR-spectroscopy revealed a significant increase in a level of “free iron”, content of transferrin active species and generation rate of NO by inducible NO-synthase in L1210 cells after aminoferrocene administration. Conclusion: Our data indicate that Benzyl-Fc Boron can be promising candidate for realizing a new strategy of anticancer therapy with the use of ROS-inducing agents.

Lectin detection of cell surface saccharides remodeling induced by development of P-glycoprotein mediated multidrug resistance phenotype in L1210 leukemia cells

P-glycoprotein is an ATP dependent drug efflux pump the expression of which is responsible for strong depression of cell sensitivities to large group of structurally unrelated substances in neoplastic cells. We found that the expression of this protein in mice leukemia cells L1210 is associated with massive remodeling of cell surface saccharides. This remodeling is consistent with the alteration of cellular contents of UDP-sugars, glycogen and glycoproteins when P-gp positive and P-gp negative L1210 cell variants were compared. The current paper is focused on bringing the state of art information about this topic.

Evaluation of Selected Honey and One of Its Phenolic Constituent Eugenol against L1210 Lymphoid Leukemia

People affected with leukemia are on the rise and several strategies were employed to thwart this deadly disease. Recent decade of research focuses on phenolic constituents as a tool for combating various inflammatory, cancer, and cardiac diseases. Our research showed honey and its phenolic constituents as crusaders against cancer. In this work, we explored the antileukemic activity of selected honey and one of its phenolic constituent eugenol against L1210 leukemia animal model. Results of this experiment showed that the selected honey samples as well as eugenol after intraperitoneal injection could not increase the median survival time (MST) of animals. Further, there was only slight marginal increase in the %T/Cvalues of honey and eugenol treated groups. The number of phenolics present in the honey may not be a prime factor to promote antileukemic effect since there was no difference in the MST of two different honeys tested. This study limits the use of selected honey and eugenol against leukemia animal model.