Could miR-34a Inhibition be Used as a Tool to Overcome Drug Resistance in MCF-7 Cells Treated with Synthesized Steroidal Heterocycles?

BACKGROUND: Progesterone derivatives have explored an improved effect on human cancer cells through combination of the explored heterocycles with progesterone moiety.miRNAs have an important role in moderating cancer cell survival, proliferation and drug resistance. The current study tested the hypothesis "whether miR-34a inhibitor has a negative impact on apoptosis and angiogenesis in MCF-7 cells treated with newly synthesized progesterone derivatives". METHODS: MCF-7 cells were treated with progesterone derivatives individually and in combination with miR-34a inhibitor. miR-34a expression levels were measured in MCF-7 cells treated with progesterone derivatives using QRT-PCR. MCF-7 cells treated with progesterone derivatives individually showed increased miR-34a expression levels. miR-34a deficient cells were treated with the newly synthesized progesterone derivatives, after that, apoptotic and angiogenic gene expression levels were determined using QRT-PCR. The studied genes were as follows: apoptotic (Bcl-2, survivin, CCND1, CDC2, P53 and P21) and angiogenic (VEGF, Hif-1α, MMP-2, Ang-1, Ang-2, and FGF-1). RESULTS: The results showed that miR-34a deficient MCF-7 cells treated with the newly progesterone derivatives still have promising effects on apoptotic and angiogenic genes. Besides, results revealed that miRNA-34a deficient MCF-7 cells exhibited improved effect of tested compounds in some apoptotic and angiogenic genes such as CDC-2, MMP-2. CONCLUSION: These results revealed that miR-34a inhibitor did not have remarkable negative effect on apoptosis and angiogenesis. On contrary, it showed an improved effect on some genes. And consequently, miR-34a inhibitor could be used safely as a tool to tackle drug resistance in breast cancer cells.

The Effect of Newly Synthesized Heterosteroids on miRNA34a, 98, and 214 Expression Levels in MCF-7 Breast Cancer Cells.

Hybrid anticancer drugs have emerged as great therapeutic options that can effectively overcome most obstacles facing conventional anticancer drugs. miRNAs are considered as class of non-coding RNAs that can negatively regulate protein coding gene expression. miRNA expression is commonly altered in cancer cells. The current work aimed to test the effect of new pro-apoptotic heterosteroids on some drug resistance related miRNAs expression levels (miRNA34a, 98, and 214) in MCF-7 breast cancer cells. After cell treatment with these compounds 4, 6, 7, 13, 18, 21, 22 and 24, miRNAs were extracted and subjected to reverse transcription and subsequent PCR amplification using Real Time-PCR technique. The expression levels of miR-34a, miR-98 and miR-214 were quantitatively determined. The study revealed that the expression levels of miR-34a, miR-98 and miR-214 were up-regulated upon treatment with tamoxifen, which was used as a positive control drug, as compared to control cells,. Strikingly, the levels of miR-34a, miR-98 and miR-214 expression were significantly down-regulated when treated with most of the new heterosteroids as compared to control cells. These results could indicate the promising effects of these new heterosteroids on reducing drug resistance as compared to tamoxifen drug. As well established, cells develop drug resistance to tamoxifen.

Novel pregnenolone derivatives modulate apoptosis via Bcl-2 family genes in hepatocellular carcinoma in vitro.

A series of pregnenolone derivatives were synthesized and assessed for anti-cancer activity against hepatocellular carcinoma cell line (HepG2). The synthesized hetero-steroids (compounds 3, 4, 5, 6, 7, 8a and 8b) were evaluated for their cytotoxic activities using MTT (3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide) assay. Apoptotic activity was assessed using dual acridine orange/ethidium bromide staining method and DNA fragmentation assay. Pro-apoptotic genes (Bax and Bak) and anti-apoptotic genes (Bcl-2 and Bcl-xL) were analyzed using quantitative real time PCR. The results revealed that compounds 4 and 6 displayed cytotoxic activity (IC50s, 36.97 ±â€¯2.18 and 18.46 ±â€¯0.64 µM, respectively), while compounds 5 and 7 exhibited weak cytotoxic activity (IC50s, 93.87 ±â€¯8.30 µM and 93.48 ±â€¯4.14 µM, respectively). All synthesized heterocyclic pregnenolone derivatives induced apoptosis through DNA fragmentation. Compounds 4 and 6 increased early and late apoptotic cell percentages while compounds 3, 5, 7 and 8b increased either early or late apoptotic cell percentage. Moreover, compounds 3, 6 and 8b up-regulated the expression level of Bak gene. On the other hand, compounds 4, 5, 7 and 8a down-regulated the Bcl-2 expression level, besides, compounds 5, 7 and 8a down-regulated the Bcl-xL expression level. Compounds 5, 7, 8a and 8b increased the Bak/Bcl-xL ratio, besides, compound 8a raised the Bax/Bcl-xL ratio whereas compound 5 elevated Bax/Bcl-2 and Bak/Bcl-2 ratios. The present work introduced novel pro-apoptotic pregnenolone derivatives that acted against HepG2 cells through DNA fragmentation, apoptotic morphological changes and were able to increase the pro-apoptotic/anti-apoptotic ratios of Bcl-2 family genes. This study particularly revealed that the cytotoxic compound 4 is the most promising pro-apoptotic compound among other synthesized derivatives where it induced apoptosis (late and early) through the down-regulation of Bcl-2 gene expression level.

The effect of newly synthesized progesterone derivatives on apoptotic and angiogenic pathway in MCF-7 breast cancer cells.

Due to its high potency and selectivity, anticancer agents consisting of combined molecules have gained great interests. The current study introduces newly synthesized progesterone derivatives of promising anticancer effect. Moreover, the pro-apoptotic and anti-angiogenic effects of these compounds were studied extensively. Several thiazole, pyridine, pyrazole, thiazolopyridine and pyrazolopyridine progesterone derivatives were synthesized. The structure of the novel progesterone derivatives was elucidated and confirmed using the analytical and spectral data. This novel derivatives were tested for their cytotoxic effect against human breast cancer cells (MCF-7) using neutral red uptake assay. Tested compounds showed anticancer activity against MCF-7 cancer cell line in the descending order of 7>2>3>8>6>9>4. The expression levels of Bcl-2, survivin, CCND1, CDC2, P53 and P21, VEGF, Hif-1α, MMP-2, MMP-9, Ang-1, Ang-2, and FGF-1 genes were investigated using QRT-PCR (Quantitative real time-polymerase chain reaction). The study clarified that compounds 2, 3, 4, 6, 7, 8 and 9 showed significant pro-apoptotic effect through the down regulation of Bcl-2., besides, survivin and CCND1 expression levels were down regulated by compounds 3, 4, 6, 7, 8, 9. However, Compound 4 may exert this pro-apoptotic effect through the up-regulation of P53 gene expression. On the other hand, the anti-angiogenic effect of these newly synthesized derivatives was due to their down regulation of VEGF, Ang-2, MMP-9 and FGF-1; and the up-regulation of HIF-1α and ang-1. This study recommended promising pro-apoptotic and anti-angiogenic anticancer agents acting through the regulation of key regulators of apoptosis, cell cycle genes, and pro-angiogenic genes.

Synthesis, Characterization, and Evaluation of Cytotoxic Effects of Novel Hybrid Steroidal Heterocycles as PEG Based Nanoparticles

Anticancer agents featuring hybrid molecules can improve effectiveness and diminish drug resistance. The current study aimed to introduce newly synthesized heterocyclic steroids of promising anticancer effects loaded in polyethylene glycol (PEG)•based nanoparticles form. Several heterocyclic steroids (1-9) were synthesized via multicomponent reactions (MCRs) and confirmed via the analytical and spectral data. Compounds 1, 2, 3, 4, 5, 6, 7 and 9, were investigated individually in their free and PEG based nano-size hybrid forms as anticancer agents against three human cell lines: hepatocellular carcinoma cells (HepG2); breast cancer cells (MCF-7); and colon cancer cells (HCT116). The neutral red supravital dye uptake assay was employed. Compound 6 in its PEG based nano-size form exhibited the best cytotoxic effects against HepG2 and HCT116 cell lines, with IC50 values of 2.44 µmol/l and 2.59 µmol/l, respectively. In addition, it demonstrated a low IC50 value against MCF-7 (3.46µmol/l) cells. This study introduced promising anticancer agents acting through conversion into PEG-based nanoparticles.

Evaluation of heterocyclic steroids and curcumin derivatives as anti-breast cancer agents: Studying the effect on apoptosis in MCF-7 breast cancer cells.

Anticancer agents consisting of hybrid molecules are used to improve effectiveness and diminish drug resistance. The current study aimed to introduce newly synthesized hetero-steroids of promising anticancer effects. Besides, the pro-apoptotic effects of new compounds were investigated extensively. Several pyrimidino-, triazolopyrimidino-, pyridazino-, and curcumin-steroid derivatives were synthesized, elucidated and confirmed using the spectral and analytical data. The synthesized hetero-steroids, compounds 9, 10, 11, 12, 13, 14, 15, 18, 20, 21, 22 and 24, were tested for their cytotoxic effects versus human breast cancer cells (MCF-7) using neutral red supravital dye uptake assay. Compound 24 (IC50=18µM) showed more inhibitory influence on MCF-7 growth. Using QRT-PCR (Quantitative real time-polymerase chain reaction), CCND1, Survivin, BCL-2, CDC2, P21 and P53, genes expression levels were investigated. The study results disclose that compounds 4, 7, 18, 24 knocked down the expression levels of CCND1, Survivin, BCL-2 and CDC2. However, P21 and P53 were up-regulated by compounds 21, 22. This study introduced promising pro-apoptotic anticancer agents acting through the modulation of key regulators of apoptosis and cell cycle genes.

Synthesis of novel steroidal curcumin derivatives as anti-Alzheimer's disease candidates: Evidences-based on in vivo study.

Alzheimer's disease (AD) is a complex disease in which a single monofunctional 'targeted' drug is uneffective for management. Hybrid drugs that impact multiple targets simultaneously are better at controlling such complex disease systems. Hybrid agents were synthesized through the combination of the steroid moiety with curcumin molecule. Also novel curcumin analogues containing promising heterocyclic nucleus fused to the essential pharmacophoric feature of the curcumin moiety, were synthesized. The aim of the present study was extended to elucidate the efficacy of these novel synthesized compounds in the regression of AD induced in adult female albino rats. The results revealed that treatment of AD groups with compounds 3, 5, 8c or rivastigmin experienced significant increase in brain Ach, GSH, paraoxenase and BCL2 levels with respect to untreated group associated with significant decrease in brain AchE activity, urinary 8-OHG level, serum Caspase-3 level and brain P53 level relative to the untreated group. Immunohistochemical investigation revealed that the selected treatments caused marked increase in ChAT positive cells. These findings were documented by the histological investigation of the brain tissue. The activity of tested compounds showed gradual increase from compound b followed by compound 8c then compound 5. The anti-cholinesterase potential, anti-oxidant properties and anti-apoptotic activity are responsible for the anti-Alzheimer's disease potential of these compounds.

Cytotoxicity and gene expression profiles of novel synthesized steroid derivatives as chemotherapeutic anti-breast cancer agents.

Anti-cancer agents which combine two biologically active compounds in one such as steroidal heterocyclic derivatives attain both hormone and cytotoxic effects on cancer cells. The aim of the present study is to synthesize and evaluate new potential chemotherapeutic anti-breast cancer agents. Several pyridazino-, pyrimido-, quinazolo-, oxirano- and thiazolo-steroid derivatives were synthesized. The structure of the novel steroid derivatives was confirmed using the analytical and spectral data. The most structurally promising of the novel synthesized steroid derivatives, compounds 8, 12, 17, 20, 22c, 24c, 30a and 30b, were investigated individually as anti-breast cancer agents against human breast cancer cells (MCF-7) using sulforhodamine B (SRB) assay. The tested compounds 17, 20, 22c and 8 showed potent broad spectrum cytotoxic activity in vitro after 48 h incubation. Compound 17 (IC(50)=2.5 µM) exhibited more inhibitory influence on MCF-7 growth than the reference drug doxorubicin (Dox) (IC(50)=4.5 µM) after 48 h incubation. Also, the present study showed that all the tested steroid derivatives exhibited significant depletion with various intensities in gene expression of breast cancer related genes (VEGF, CYP19 and hAP-2γ). Noteworthy, compounds 17, 20 and 22c showed the most pronounced effect in this respect.

Development of new indole-derived neuroprotective agents.

There is a great deal of interest in neurotrophin therapy to prevent neuronal degeneration. The present study aimed at synthesizing new functionalized indole derivatives with structures justifying neuroprotective activity using L-tryptophan (TRP) as starting material. The potential neuroprotective effect of these newly synthesized agents against acrylamide (ACR) induced neurotoxicity was investigated in adult female rats. The novel indole derivatives, indolylmethyl pyridine derivatives 9a,b, pyrimidinylindolyl propanone derivatives 12a-c, pyrazolylindolyl propanone derivatives 14a,b, and indolyl tetrazolopropanoic acid derivative 17 were synthesized and their chemical structures were confirmed by studying their analytical and spectral data. The administration of ACR [ip, 50mgkg(-1) body weight (b. wt.)] alone resulted in significant increase in brain malondialdehyde level (MDA) and lactate dehydrogenase (LDH) activity whereas it caused significant decrease in brain monoamines levels and antioxidant enzymes activity. Treatment with the indole derivatives 9b, 12c, 14a, and 17 (ip, 50mgkg(-1) b. wt.) prior to ACR produced neuroprotective activity with various intensities depending on the structure of each compound. Compound 17 in which the tetrazole ring was attached to the TRP moiety ranked as the strongest neuroprotective agent. All the tested compounds have been shown to possess antioxidant properties offering promising efficacy against oxidative stress induced by ACR administration.

Potent neuroprotective role of novel melatonin derivatives for management of central neuropathy induced by acrylamide in rats.

Acrylamide (ACR) has been shown to be a neurotoxic agent for both laboratory animals and human. The present study aimed at synthesizing new functionalized melatonin derivatives bearing promising heterocyclic moiety that could be expected to have protective effect against ACR-induced neurotoxicity in adult female rats. The novel melatonin derivatives 4, 6, 7 and 11 were synthesized and their chemical structures were confirmed by studying their analytical and spectral data. The administration of ACR [i.p., 50 mg kg(-1) body weight (b. wt.)] alone resulted in significant increase in brain malondialdehyde level (MDA) and lactate dehydrogenase (LDH) activity whereas it caused significant decrease in brain monoamines levels and antioxidant enzymes activity. Treatment with melatonin derivatives 4, 6, 7 and 11 (i.p., 50 mg kg(-1) b. wt) prior to ACR produced significant decrease in brain MDA level and LDH activity with concomitant significant increase in brain monoamines and antioxidant enzymes activity. It could be concluded that the new synthesized melatonin derivatives exhibited promising protective activity against ACR-induced neurotoxicity.