Thiophene Derivatives as Anticancer Agents and Their Delivery to Tumor Cells Using Albumin Nanoparticles

Exosomes as smart drug delivery vehicles for cancer immunotherapy

Exosomes (Exos) as drug delivery vehicles have been widely used for cancer immunotherapy owing to their good biocompatibility, low toxicity, and low immunogenicity. Some Exos-based cancer immunotherapy strategies such as tuning of immunosuppressive tumor microenvironment, immune checkpoint blockades, and cancer vaccines have also been investigated in recent years, which all showed excellent therapeutic effects for malignant tumor. Furthermore, some Exos-based drug delivery systems (DDSs) for cancer immunotherapy have also undergone clinic trails, indicating that Exos are a promising drug delivery carrier. In this review, in order to promote the development of Exos-based DDSs in cancer immunotherapy, the biogenesis and composition of Exos, and Exos as drug delivery vehicles for cancer immunotherapy are summarized. Meanwhile, their clinical translation and challenges are also discussed. We hope this review will provide a good guidance for Exos as drug delivery vehicles for cancer immunotherapy.

Facile synthesis of a triazine-based porous organic polymer containing thiophene units for effective loading and releasing of temozolomide

Suzuki cross-coupling reaction was employed to easily obtain a triazine-based porous organic polymer (2,4,6-tris(5-bromothiophene-2-yl)-1,3,5-triazine [TBrTh]–1,3,5-benzene-triyltriboronic acid pinacol ester [BTBPE]–covalent triazine framework [CTF]) containing thiophene units. The chemical structure of TBrTh–BTBPE–CTF was revealed by solid-state 13C NMR, Fourier-transform infrared, and X-ray photoelectron spectroscopy. TBrTh–BTBPE–CTF with an amorphous structure exhibited excellent thermal stability and intrinsic porosity (373 m2·g−1 of Brunauer–Emmett–Teller surface area). Consequently, temozolomide (TMZ) was used as an oral alkylating agent in melanoma treatment to explore the drug loading and releasing behavior of TBrTh–BTBPE–CTF as a result of the low cytotoxicity of thiophene-based polymers. The successful loading of TMZ within the polymeric structure was suggested by thermogravimetric analysis and N2 sorption isotherms. The release experiments were performed in phosphate-buffered saline at pH values of 5.5 and 7.4, exhibiting good controlled-release properties. These results suggest that the current porous organic polymer is expected to be a drug carrier for the delivery and release of TMZ.

Hypoxia-Activated Albumin-Binding Exatecan Prodrug for Cancer Therapy

As an effective drug delivery strategy for traditional antitumor drugs, the stimulus-responsive albumin-based prodrugs are getting more and more attention. These prodrugs only release drugs in specific tumor microenvironments, which can prevent premature release of the drug in the circulation. Tumor hypoxia is a fundamental feature of the solid tumor microenvironment. As a hypoxia-activated linker, the 5-position branched linker of 1-methyl-2-nitro-5-hydroxymethylimidazole can be a trigger for albumin-based prodrugs. In this study, we report the synthesis and biological evaluation of the hypoxia-activated albumin-binding prodrug Mal-azo-Exatecan. After intravenous administration, the maleimide on the side chain can rapidly bind to endogenous albumin, enabling the prodrugs to accumulate in tumors, where tumor-associated hypoxia microenvironments trigger the selective release of Exatecan. The 5-position branched linker of 1-methyl-2-nitro-5-hydroxymethylimidazole as a cleavable linker has high plasma stability and does not cause Exatecan release from HSA-azo-Exatecan during circulation in vivo, avoiding systemic side effects caused by Exatecan.

Synthesis, Biological, and Molecular Docking Studies on 4,5,6,7-Tetrahydrobenzo[b]thiophene Derivatives and Their Nanoparticles Targeting Colorectal Cancer

Initiation of colorectal carcinogenesis may be induced by chromosomal instability caused by oxidative stress or indirectly by bacterial infections. Moreover, proliferating tumor cells are characterized by reprogrammed glucose metabolism, which is associated with upregulation of PDK1 and LDHA enzymes. In the present study, some 4,5,6,7-tetrahydrobenzo[b]thiophene derivatives in addition to Fe₃O₄ and Fe₃O₄/SiO₂ nanoparticles (NPs) supported with a new Schiff base were synthesized for biological evaluation as PDK1 and LDHA inhibitors as well as antibacterial, antioxidant, and cytotoxic agents on LoVo and HCT-116 cells of colorectal cancer (CRC). The results showed that compound 1b is the most active as PDK1 and LDHA inhibitor with IC₅₀ values (μg/mL) of 57.10 and 64.10 compared to 25.75 and 15.60, which were produced by the standard inhibitors sodium dichloroacetate and sodium oxamate, respectively. NPs12a,b and compound 1b exhibited the strongest antioxidant properties with IC₅₀ values (μg/mL) of 80.0, 95.0, and 110.0 μg/mL, respectively, compared to 54.0 μg/mL, which was produced by butylated hydroxy toluene. Moreover, NPs12a and carbamate derivative 3b exhibited significant cytotoxic activities with IC₅₀ values (μg/mL) of 57.15 and 81.50 (LoVo cells) and 60.35 and 71.00 (HCT-116 cells). Thus, NPs12a and compound 3b would be considered as promising candidates suitable for further optimization to develop new chemopreventive and chemotherapeutic agents against these types of CRC cell lines. Besides, molecular docking in the colchicine binding site of the tubulin (TUB) domain revealed a good binding affinity of 3b to the protein; in addition, the absorption, distribution, metabolism, and excretion (ADME) analyses showed its desirable drug-likeness and oral bioavailability characteristics.

Cyclotrisiloxan and β-Sitosterol rich Cassia alata (L.) flower inhibit HT-115 human colon cancer cell growth via mitochondrial dependent apoptotic stimulation

Cancer traits dependent chemo and radiotherapy display acute toxicity and long-term side effects. Since last two decades, researchers investigated a new anticancer agents derived from plants. Cassia alata (L.) is a medicinal herb distributed in the tropical and humid regions. In this study, C. alata flower methanol extract (CME) have been prepared using cold percolation method and the phytochemical components were identified using GC–MS analysis. CME have been used to study the antiproliferative and apoptosis properties against human colon cancer HT-115 colon cancer cells, its molecular mechanism have been explored. 0.2 mg/mL dose of CME, inhibited 50% of HT-115 colon cancer cell growth after 48hr was confirmed the significant antiproliferation effect. In normal cells such as Vero cells and hMSCs, 0.2 mg/mL dose of CME shown only 4% and 5% growth inhibition confirmed the HT-115 cell specific cytotoxic effect. This effect might be due to the availability of phytoactive biomolecules in CME such as, cyclotrisiloxan, beta-sitosterol and alpha-tocopherol have been confirmed by GC–MS. Most interestingly, PI and AO/ErBr staining of CME treated HT-115 cells shown early (25%), pro (17%) and late (8%) apoptotic and 3% necrotic cells after 48 hr. Treatment with CME extract showed potential effect on the inhibition of protumorigenic inflammatory and oxidative stress genes. Protumorigenic COX-2/PGE-2 and TNF-α/NF-κB immune axis were normalized after CME treatment. Amounts of both apoptosis related mRNA p53, Bax, caspase 3 and p21 genes were upregulated, whereas it resulted in significant reduction in the anti-apoptotic marker mdm2 and Bcl-2 genes. In conclusion, bioactive compounds present in CME potentially inhibit HT-115 colon cancer cell proliferation via an inhibition of protumorigenic immune axis and stimulation of mitochondria dependent apoptotic pathway without necrotic effect.

Diverse Thiophenes as Scaffolds in Anti-cancer Drug Development: A Concise Review

Thiophenes are one of the abundantly found heterocyclic ring systems in many biologically active compounds. Moreover, various substituted thiophenes exert numerous pharmacological actions on account of their isosteric resemblance with compounds of natural origin, thus rendering them with diverse actions like antibacterial, antifungal, antiviral, anti-inflammatory, analgesic, antiallergic, hypotensives, etc. In this review, we specifically explore the chemotherapeutic potential of a variety of structures consisting of thiophene scaffolds as prospective anticancer agents.

A Review on Anticancer Activities of Thiophene and Its Analogs

Cancer is the world's second-largest cause of mortality and one of the biggest global health concerns. The prevalence and mortality rates of cancer remain high despite significant progress in cancer therapy. The search for more effective, as well as less toxic treatment methods for cancer, is at the focus of current studies. Thiophene and its derivatives have surged as an influential scaffold, which, because of their appreciable diversity in biological activities, has drawn the concerned interest of the researchers in the field of medicinal chemistry. By the affluent introduction of its derivatives, which have antioxidant, anti-inflammatory, antimicrobial, and anticancer activities, the adaptability of the thiophene moiety has been displayed. The nature and positioning of the substitutions significantly impacted thiophene moiety activity. This decent array in the living response account about this moiety has picked plentiful researcher's consideration to inquire about it to its peculiar potential across certain activities. In the field of cancer therapy against different cancer cells, the structure-activity relationship for each of the derivatives showed an excellent understanding of thiophene moiety. Information from the various articles revealed the key role of thiophene moiety and its derivatives to develop the vital lead compound. The essential anticancer mechanisms identified include inhibition of the topoisomerase, inhibition of tyrosine kinase, tubulin interaction and apoptosis induction through the activation of reactive oxygen species. This review is an endeavor to promote the anticancer potential of the derivatives, whether having thiophene or condensed thiophene as a core moiety or as a substituent that can lead in the future to synthesize varieties of chemotherapeutic entities in the field of cancer treatment.

Molecular structure, IR, Raman and UV-VIS spectra of 2-cyanothiophene and 3-cyanothiophene: A comparative quantum chemical investigation

Spectroscopic data which are needed for detection of new species in the interstellar medium (ISM) are missing for five- and six-membered ring substituted derivatives. In order to supplement the existing literature information, quantum chemical calculations, including geometrical optimizations, simulated IR, Raman and UV-VIS spectra were carried out for 2-cyanothiophene (2CNT) and 3-cyanothiophene (3CNT). Structures for these molecular species were calculated from M06-2X/6-31G(d,p) computed results in conjunction with corrections for systematic deficiencies of basis sets and empirical adjustments for some geometrical parameters. A complete description of IR and Raman spectra including IR frequency assignment and potential energy distribution (PED) analysis is provided. IR and Raman spectra for deuterated species and UV-VIS spectra for thiophene, 2CNT and 3CNT were analyzed. The present computed molecular data are expected to assist astro-scientists in the search of these species in the ISM.

Cell-Penetrating Peptide and Transferrin Co-Modified Liposomes for Targeted Therapy of Glioma

Glioma is one of the most aggressive and common malignant brain tumors. Due to the presence of the blood-brain barrier (BBB), the effectiveness of therapeutics is greatly affected. In this work, to develop an efficient anti-glioma drug with targeting and which was able to cross the BBB, cell-penetrating peptides (R8) and transferrin co-modified doxorubicin (DOX)-loaded liposomes (Tf-LPs) were prepared. Tf-LPs possessed a spherical shape and uniform size with 128.64 nm and their ξ-potential was 6.81 mV. Tf-LPs were found to be stable in serum within 48 h. Uptake of Tf-LPs in both U87 and GL261 cells was analyzed by confocal laser scanning microscopy and by flow cytometry. Tf-LPs were efficiently taken up by both U87 and GL261 cells. Moreover, Tf-LPs exhibited sustained-release. The cumulative release of DOX from Tf-LPs reached ~50.0% and showed excellent anti-glioma efficacy. Histology of major organs, including brain, heart, liver, spleen, lungs and kidney, and the bodyweight of mice, all indicated low toxicity of Tf-LPs. In conclusion, Tf-LPs showed great promise as an anti-glioma therapeutic agent.