Radioiodinated acebutolol as a new highly selective radiotracer for myocardial perfusion imaging

Pristine/folate-functionalized graphene oxide as two intrinsically radioiodinated nano-theranostics: self/dual in vivo targeting comparative study

Background

Nanomedicine offers great potentials for theranostic studies via providing higher efficacy and safety levels. This work aimed to develop and evaluate a new nanoplatform as a tumor theranostic probe.

Results

Carboxyl-functionalized graphene oxide nanosheets (FGO) was well synthesized from graphite powder and then conjugated with folic acid to act as a targeted nano-probe. Full characterization and in vitro cytotoxicity evaluation were conducted; besides, in vivo bio-evaluation was attained via intrinsic radioiodination approach in both normal and tumor-bearing Albino mice. The results indicated that FGO as well as conjugated graphene oxide nanosheets (CGO) are comparatively non-toxic to normal cells even at higher concentrations. Pharmacokinetics of FGO and CGO showed intensive and selective uptake in the tumor sites where CGO showed high T/NT of 7.27 that was 4 folds of FGO at 1 h post injection. Additionally, radioiodinated-CGO (ICGO) had declared a superior prominence over the previously published tumor targeted GO radiotracers regarding the physicochemical properties pertaining ability and tumor accumulation behavior.

Conclusions

In conclusion, ICGO can be used as a selective tumor targeting agent for cancer theranosis with aid of I-131 that has a maximum beta and gamma energies of 606.3 and 364.5 keV, respectively.

New frontier radioiodinated probe based on in silico resveratrol repositioning for microtubules dynamic targeting

PURPOSE

As the 'de novo' drug discovery faces a highly attrition rates, drug repositioning procures a heighten concern in identifying novel uses for existing medications. This study aimed to fabricate radioiodinated resveratrol as a potent microtubules interfering agent for cancer theragnosis.

METHODS

Resveratrol was radiolabeled with radioactive iodine where the radioiodination efficiency was enlightened and the computational approaches were employed to investigate the affinity and specificity with tubulins. Furthermore, the in-vivo distribution and pharmacokinetic studies in normal and tumor induced mice were investigated.

RESULTS

The maximum radioiodination yield (94.6 ± 1.66) was achieved at optimum preparation parameters stated as 100 μg/mL of oxidizing agent, 100 μg/ml of resveratrol, reaction time of 30 min and reaction pH 5. The in silico studies showed that di-iodinated resveratrol (compound 6) exhibited the best binding score (-34.46) and interaction with the β-tubulin binding site. The in vivo distribution in tumor models revealed a significant accumulation (4.02% ID/g) in tumor lesion at 60 min p.i. The rate of drug elimination demonstrated a mono-exponential decline of radioactivity versus time in the blood.

CONCLUSION

Radioiodinated resveratrol revealed good microtubules targeting which render it as a novel theranostic probe for cancer management.

New 5-Aryl-1,3,4-Thiadiazole-Based Anticancer Agents: Design, Synthesis, In Vitro Biological Evaluation and In Vivo Radioactive Tracing Studies

A new series of 5-(4-chlorophenyl)-1,3,4-thiadiazole-based compounds featuring pyridinium (3), substituted piperazines (4a-g), benzyl piperidine (4i), and aryl aminothiazoles (5a-e) heterocycles were synthesized. Evaluation of the cytotoxicity potential of the new compounds against MCF-7 and HepG2 cancer cell lines indicated that compounds 4e and 4i displayed the highest activity toward the tested cancer cells. A selectivity study demonstrated the high selective cytotoxicity of 4e and 4i towards cancerous cells over normal mammalian Vero cells. Cell cycle analysis revealed that treatment with either compound 4e or 4i induced cell cycle arrest at the S and G2/M phases in HepG2 and MCF-7 cells, respectively. Moreover, the significant increase in the Bax/Bcl-2 ratio and caspase 9 levels in HepG2 and MCF-7 cells treated with either 4e or 4i indicated that their cytotoxic effect is attributed to the ability to induce apoptotic cell death. Finally, an in vivo radioactive tracing study of compound 4i proved its targeting ability to sarcoma cells in a tumor-bearing mice model.

Histopathology, pharmacokinetics and estimation of interleukin-6 levels of Moringa oleifera leaves extract-functionalized selenium nanoparticles against rats induced hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most dangerous cancers in all the world. This study focused on prevention and therapy of hepatocellular carcinoma (HCC) using Moringa oleifera extract combined with vitamin C and selenium in a nanoplatform (MO/asc.-Se-NPs).

Results

Full characterization of MO/asc.-Se-NPs was performed by using different analytical techniques (TEM, DLS, zeta-sizer), and its antioxidant capacity was measured by DPPH assay. Biodistribution study was performed with the aid of radiolabeling technique using technetium-99m in normal albino mice. HCC was induced in Wister albino rats to evaluate the efficiency of MO/asc.-Se-NPs in the treatment of HCC. The biomarker analysis (ALT, AST and ALB) shows improvement in its values in prevention and treated groups by using MO/asc.-Se NP. The levels of inflammatory marker interleukin 6 (IL6 tissue homogenate) was improved by decreasing its values in these two groups also. Histology section of tissue liver showed alleviation in treated and prevention groups.

Conclusions

In conclusion, MO/asc.-Se-NPs can be used as a potential agent for prevention and treatment of HCC after further preclinical studies.

Extraction, purification and radioiodination of Khellin as cancer theranostic agent

Khellin was successfully extracted from Ammi visnaga fruits with a recovery percent of 96.15%. Next radio-iodination of Khellin was successfully achieved with a high yield. The biodistribution study of [¹³¹I]iodo-khellin in tumour bearing mice revealed that khellin preferentially localization at tumour tissue. Target prediction study for [¹³¹I]iodo-khellin revealed that PI3K and VEGFR are potential targets for iodo-khellin with good affinity. The results of this study potentiate [¹³¹I]iodo-khellin as a good theranostic agent for tumour imaging and therapy.

Amelioration of Tumor Targeting and In Vivo Biodistribution of 99mTc-Methotrexate-Gold Nanoparticles (99mTc-Mex-AuNPs)

Gold nanoparticles (AuNPs) represent very attractive and promising drug delivery carriers due to their unique dimensions, adjustable surface functions, and controllable drug release. Therefore, AuNPs are used to overcome the limitations of conventional chemotherapy, for example methotrexate (Mex), one of the first-generation chemotherapy drugs for cancer treatment, whose usefulness has been restricted due to drug resistance and dose-dependent side effects. In the present study, the AuNPs drug delivery system was synthesized and loaded with technetium-99 m radiolabeled Methotrexate (^99mTc-Mex) to produce new potential nanoradiopharmaceutical for tumor targeting and further imaging. The Methotrexate loaded gold nanoparticles (Mex-AuNPs) successfully prepared in small spherical particle size (20.3 nm), polydispersity index PDI (< 0.5) and a zeta potential (-17.6 mV) with loading efficiency% (93 ± 1.2%) of methotrexate at 30 min as an optimum stirring time and showed strong absorption peak for Mex-AuNPs at λ_max, 525 nm. The in vitro release profile of Mex-AuNPs showed high release percent of methotrexate at pH 5; the Q_0.5 h and Q_8h were 21.2 ± 1.5% and 92.9 ± 3.4%, respectively. The in vitro cytotoxicity was investigated at different concentrations (0.024-50 μl/100 μl) of Mex-AuNPs (1 mg/ml) against MCF-7 (Michigan Cancer Foundation-7) breast cancer cells by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay technique. Mex-AuNPs showed higher anticancer activity with low inhibitory concentration (IC₅₀ = 0.098 μl/100 μl) that was three times lower than the inhibitory concentration (IC₅₀) of methotrexate (IC₅₀ = 0.3 μl/100 μl). ^99mTc-Mex complex prepared by direct reduction method at maximum radiochemical yield (RCY)% ̴ 98.3 ± 1.09 % was loaded in AuNPs to form ^99mTc-Mex-AuNPs with loading efficiency% (93 ± 1.2 %) at 30 min of stirring time. ^99mTc-Mex-AuNPs showed convenient in vitro stability in mice serum up to 24 h with RCY% > 90 %. The preclinical biodistribution studies of ^99mTc-Mex-AuNPs were performed in 3 experimental groups A (intravenous (I.V.) injected normal mice), B and C (I.V. and intratumor (I.T.) injected tumor bearing mice, respectively). The ^99mTc-Mex-AuNPs achieved highest tumor uptake (93 ± 0.39 %ID/g) and highest Target/NonTarget (T/NT) ratio (58.1 ± 0.91) with high Tumor/Blood (T/B) ratio (25.8 ± 0.11) at 10 min post I.T. injection and retained high tumor uptake (79 ± 0.65 %ID/g) up to 60 min post I.T. injection before escaping into blood stream. Consequently, ^99mTc-Mex-AuNPs can be considered as new potential nanoradiopharmaceutical in tumor diagnosis.

New quinoxaline compounds as DPP-4 inhibitors and hypoglycemics: design, synthesis, computational and bio-distribution studies

The current work represents the design and synthetic approaches of a new set of compounds 6–10 bearing the 1,4-dimethyl-2,3-dioxo-1,2,3,4-tetrahydroquinoxaline-6-sulfonamide scaffold. The biological evaluation revealed that most of the new compounds were promising selective dipeptidyl peptidase-IV (DPP-4) inhibitors and in vivo hypoglycemic agents utilizing linagliptin as a standard drug. The acute toxicity examination confirmed the safety profile of all compounds. Molecular docking studies related the significant DPP-4 suppression activity of compounds 9a, 10a, 10f, 10g to their nice fitting in the active pocket of DPP-4. In addition, the molecular dynamic study exhibited the stability of both 10a and 10g within the active site of DPP-4. The QSAR study showed that the difference between the predicted activities is very close to the experimental suppression effect. Moreover, both compounds 10a and 10g obeyed Lipinski's rule, indicating their efficient oral bioavailability. Compound 10a was radiolabeled, forming the ¹³¹I-SQ compound 10a to study the pharmacokinetic profile of this set of compounds. The biodistribution pattern hit the target protein since the tracer accumulated mainly in the visceral organs where DPP-4 is secreted in a high-level, thus with consequent stimulation of insulin secretion, leading to the target hypoglycemic effect.

The current work represents the design and synthetic approaches of a new set of compounds 6–10 bearing the 1,4-dimethyl-2,3-dioxo-1,2,3,4-tetrahydroquinoxaline-6-sulfonamide scaffold.

Miniaturized chromatographic systems for radiochemical purity evaluation of 131I-Ferulic acid as a new candidate in nuclear medicine applications

Recently, the anticancer activity of ferulic acid (FA) which is a caffeic acid derivative has been reported. Therefore, in this study FA was radiocaped with ¹³¹I^- to explore its potential as a tumor targeting agent. The radiolabeling process was carried out via electrophilic substitution reaction. The factors affecting labeling yield were optimized and the radiochemical purity (RCP) was assessed by various analytical techniques including paper chromatography (PC), thin layer chromatography (TLC), instant thin layer chromatography (ITLC), paper electrophoresis (PE) and high-performance liquid chromatography (HPLC). The RCP assay was extended to the utilization of miniaturized techniques including miniaturized PC (mini-PC), mini-TLC and mini-column chromatography (silica, sephadex-G25). Validation of mini-TLC, as one of ¹³¹I-FA RCP assay methods, was done according to ICH guidelines. Biodistribution studies of ¹³¹I-FA were performed on Ehrlich solid tumor bearing mice at various time points (5, 30, 60, 120 and 240 min), post injection. The radiolabeling yield of ¹³¹I-FA was 96.23 ± 0.45% and the miniaturized chromatographic systems showed high efficacy in RCP evaluation comparable to the conventional ones. Mini-TLC was proved to be specific, accurate, precise and linear. The tumor uptake of ¹³¹I-FA in solid tumor bearing mice was 4.35 ± 0.41 ID/g at 60 min with 2.79 as a tumor/muscle ratio. Consequently, ¹³¹I-FA could be used as a tumor targeting agent for nuclear medicine applications and the fast reaction monitoring could be achieved using miniaturized chromatographic techniques.

99mTc-doxorubicin-loaded gallic acid-gold nanoparticles (99mTc-DOX-loaded GA-Au NPs) as a multifunctional theranostic agent

The development of cancer theranostic nanomedicines is recommended to concurrently achieve and evaluate the therapeutic benefit and progress. The current work aims to develop gallic acid-gold nanoparticles (GA-Au NPs) as a theranostic probe for ^99mTc-Doxorubicin (^99mTc-DOX) based on the spatiotemporal release pattern induced intra-tumoral (IT) delivery. DOX-loaded GA-Au NPs were developed and identified via UV-Vis spectroscopy. The system was characterized for drug loading efficiency%, particle size, zeta potential, topography, in vitro DOX release and anti-proliferative activity against the MCF-7 cell-line. The factors influencing radiolabeling efficiency of DOX with ^99mTc (DOX concentration, stannous chloride concentration, reaction time and pH) were optimized. The in vitro stability in mice serum and in vivo distribution studies in mice of ^99mTc-DOX-loaded GA-Au NPs were investigated following IV and IT administration. Dox-loaded GA-Au NPs had a loading efficiency of 91%, a small particle size (≈50 nm), a promising zeta potential (-20 mV) and a sustained drug release profile at pH 5.3. GA-Au NPs exhibited increased anti-proliferative activity, with approximately a four-fold lower IC₅₀ value (0.15 μg/ml) than free DOX. The optimized radiolabeling efficiency of ^99mTc-DOX was ≈93%. It showed good physiological stability in mice serum for at least 8 h. The IT delivery of ^99mTc-DOX-loaded GA-Au NPs in tumor-induced mice showed dramatic tumor accumulation. A maximum magnitude of 86.73%ID/g was achieved, at 15 min post-injection, with a target/non-target ratio of ≈56. ^99mTc-DOX-loaded GA-Au NPs could be used for the selective IT delivery of a chemotherapeutic agent and an imaging agent to a target organ.

Adaptation of hard gelatin capsules for oral delivery of aqueous radiopharmaceuticals

PURPOSE

Oral administration of Iodine-131 (I-131) solutions causes high risk of contamination for patients and dispensers. The objective of the study was to adapt hard gelatin capsules (HGCs) for filling with radiopharmaceutical solutions without deformation.

METHODS

Polystyrene (PS) internally lining films with different thicknesses were used to protect HGCs. The insulated HGCs were evaluated for their physicochemical characteristics and rupturing time in different dissolution media. HGCs internally lined with PS were examined for withstand loading with different volumes and radioactivities of I-131 solutions. Radioactivity release was studied in deionized water and acidic media. Quality control of released I-131 was inspected for radiochemical purities.

RESULTS

There was a directly proportion between PS lining thickness and stability of HGCs after filling with 500 μl aqueous methylene blue solution. HGCs internally lined with PS 100 μm thickness withstand deformation for ˃ two months; however showed fast in-vitro rupturing time in different dissolution media. Internally lined HGCs loaded with different volumes and radioactivities of I-131 solutions resisted for one week without radioactive leakage. Yet, revealed complete release of I-131 after 20 min in dissolution media with great radiochemical purity.

CONCLUSION

The study promises safely I-131 aqueous solution delivery via adapted HGCs. Graphical abstract Oral administration of radiopharmaceuticals.

Iron oxide nanoparticulate system as a cornerstone in the effective delivery of Tc-99 m radionuclide: a potential molecular imaging probe for tumor diagnosis

BACKGROUND

The evolution of nanoparticles has gained prominence as platforms for developing diagnostic and/or therapeutic radiotracers. This study aims to develop a novel technique for fabricating a tumor diagnostic probe based on iron oxide nanoparticles excluding the utilization of chelating ligands.

METHODS

Tc-99 m radionuclide was loaded into magnetic iron oxide nanoparticles platform (MIONPs) by sonication. ^99mTc-encapsulated MIONPs were fully characterized concerning particles size, charge, radiochemical purity, encapsulation efficiency, in-vitro stability and cytotoxicity. These merits were biologically evaluated in normal and solid tumor bearing mice via different delivery approaches.

RESULTS

^99mTc-encapsulated MIONPs probe was synthesized with average particle size 24.08 ± 7.9 nm, hydrodynamic size 52 nm, zeta potential -28 mV, radiolabeling yield 96 ± 0.83%, high in-vitro physiological stability, and appropriate cytotoxicity behavior. The in-vivo evaluation in solid tumor bearing mice revealed that the maximum tumor radioactivity accumulation (25.39 ± 0.57, 36.40 ± 0.59 and 72.61 ± 0.82%ID/g) was accomplished at 60, 60 and 30 min p.i. for intravenous, intravenous with physical magnet targeting and intratumoral delivery, respectively. The optimum T/NT ratios of 57.70, 65.00 and 87.48 were demonstrated at 60 min post I.V., I.V. with physical magnet targeting and I.T. delivery, respectively. These chemical and biological characteristics of our prepared nano-probe demonstrate highly advanced merits over the previously reported chelator mediated radiolabeled nano-formulations which reported maximum tumor uptakes in the scope of 3.65 ± 0.19 to 16.21 ± 2.56%ID/g.

CONCLUSION

Stabilized encapsulation of ^99mTc radionuclide into MIONPs elucidates a novel strategy for developing an advanced nano-sized radiopharmaceutical for tumor diagnosis. Graphical abstract ^99mTc-encapsulated MIONPs nanosized-radiopharmaceutical as molecular imaging probe for tumor diagnosis.

Novel hydrazide-hydrazone and amide substituted coumarin derivatives: Synthesis, cytotoxicity screening, microarray, radiolabeling and in vivo pharmacokinetic studies

The current work presents the synthesis and biological evaluation of new series of coumarin hydrazide-hydrazone derivatives that showed in vitro broad spectrum antitumor activities against resistant pancreatic carcinoma (Panc-1), hepatocellular carcinoma (HepG2) and leukemia (CCRF) cell lines using doxorubicin as reference standard. Bromocoumarin hydrazide-hydrazone derivative (BCHHD) 11b showed excellent anticancer activity against all tested cancer cell lines. Enzyme assays showed that BCHHD 11b induced apoptosis due to activation of caspases 3/7. Moreover, 11b inhibited GST and CYP3A4 in a dose dependent manner and the induced cell death could be attributed to metabolic inhibition. Moreover, 11b microarray analysis showed significant up- and down-regulation of many genes in the treated cells related to apoptosis, cell cycle, tumor growth and suppressor genes. All of the above presents BCHHD 11b as a potent anticancer agent able to overcome drug resistance. In addition, compound 11b was able to serve as a chemical carrier for ^99mTc and the in vivo biodistribution study of ^99mTc-11b complex revealed a remarkable targeting ability of ^99mTc into solid tumor showing that ^99mTc-11b might be used as a promising radiopharmaceutical imaging agent for cancer.

Design, synthesis and biological evaluation of some novel sulfonamide derivatives as apoptosis inducers

Several novel thiazolidinone and fused thiazolidinone derivatives bearing benzenesulfonamide moiety were synthesized and confirmed via spectral and elemental analyses. The newly synthesized compounds were evaluated for their cytotoxic activity on colorectal cancer cell line (Caco-2). All the synthesized compounds showed better activity than the reference standards (Doxorubicin and 5-FU). Investigation of the apoptotic activity of the most active compounds revealed that compounds 3a, 5a, 5c and 6c activate both caspase-3 and Fas-ligand in Caco-2 cell line. Compound 3a was the most active compound with caspase-3 concentration of 0.43 nmol/mL and Fas-ligand concentration of 775.2 pg/mL in treated Caco-2 cells. Compound 3a was radiolabeled with ^99mTc and its biodistribution pattern was evaluated in vivo using normal Swiss Albino mice. ^99mTc-compound 3a complex didn't exhibit any accumulation in any body organs except for its accumulation in the colon; target organ; where it showed 8.97 ± 1.35 %ID/g at 15min p. i. that elevated till 16.02 ± 2.43 %ID/g at 120min p. i.