COVID-19 is a novel coronavirus with an outbreak of unusual viral pneumonia in Wuhan, China, and then pandemic. Based on its phylogenetic relationships and genomic structures the COVID-19 belongs to genera Betacoronavirus. Human Betacoronaviruses (SARS-CoV-2, SARS-CoV, and MERS-CoV) have many similarities, but also have differences in their genomic and phenotypic structure that can influence their pathogenesis. COVID-19 is containing single-stranded (positive-sense) RNA associated with a nucleoprotein within a capsid comprised of matrix protein. A typical CoV contains at least six ORFs in its genome. All the structural and accessory proteins are translated from the sgRNAs of CoVs. Four main structural proteins are encoded by ORFs 10, 11 on the one-third of the genome near the 3'-terminus. The genetic and phenotypic structure of COVID-19 in pathogenesis is important. This article highlights the most important of these features compared to other Betacoronaviruses.

Rutin is a unique antioxidant flavonoid that is mainly found in fruit, vegetables, cereals, and many other plant-based human diets. This review aims to highlight the in vitro anticancer properties of rutin including combination therapeutic strategies. Literature resources were gathered through PubMed, Scopus, Web of Science, and Google Scholar databases that cover the period of 19952021. Rutin is demonstrated to inhibit the proliferation of breast, colon, lung, and prostate cancers and other tumors. Furthermore, rutin alone or in combination with other therapeutic agents has been shown to regulate several signalling pathways involving the Ras/Raf and PI3K/Akt, MAPK, and TGF-β2/Smad2/3Akt/PTEN, etc., which are related to the processes of carcinogenesis and induction of apoptosis. The combination of rutin with other chemotherapy drugs may benefit on prevention of tumor cells by decreasing drug resistance and chemotherapy side effects. Moreover, rutin induces apoptosis synergistically with the therapeutic agent. More in vivo and clinical data are however needed to evaluate the true potential of rutin as an anticancer agent as an adjuvant. The present review highlights the effects of rutin which can be a promising candidate in combination with other antitumor drugs or alone for cancer treatment in vitro. Also, rutin can lead to decrease in drug resistance and chemotherapeutic side effects.

Resistance to temozolomide (TMZ) is the main cause of death in glioblastoma multiforme (GBM). The use of nanocarriers for drug delivery applications is one of the known approaches to overcome drug resistance. This study aimed to investigate the possible effect of selenium–chitosan nanoparticles loaded with TMZ on the efficacy of TMZ on the expression of MGMT, E2F6, and RELA genes and the rate of apoptosis in the C6 cell line. Selenium nanoparticles (SNPs) were loaded with TMZ and then they were coated by Eudragit^® RS100 (Eud) and chitosan (C_S) to prepare Se@TMZ/Eud-Cs. Physicochemical properties were determined by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDAX), thermal gravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS) methods. Se@TMZ/Eud-Cs was evaluated for loading and release of TMZ by spectrophotometric method. Subsequently, SNPs loaded with curcumin (as a fluorophore) were analyzed for in vitro uptake by C6 cells. Cytotoxicity and apoptosis assay were measured by MTT assay and Annexin-PI methods. Finally, real-time PCR was utilized to determine the expression of MGMT, E2F6, and RELA genes. Se@TMZ/Eud-Cs was prepared with an average size of 200 nm as confirmed by the DLS and microscopical methods. Se@TMZ/Eud-Cs presented 82.77 ± 5.30 loading efficiency with slow and pH-sensitive release kinetics. SNPs loaded with curcumin showed a better uptake performance by C6 cells compared with free curcumin (p-value < 0.01). Coated nanoparticles loaded with TMZ showed higher cytotoxicity, apoptosis (p-value < 0.0001), and down-regulation of MGMT, E2F6, and RELA and lower IC50 value (p-value < 0.0001) than free TMZ and control (p-value < 0.0001) groups. Using Cs as a targeting agent in Se@TMZ/Eud-Cs system improved the possibility for targeted drug delivery to C6 cells. This drug delivery system enhanced the apoptosis rate and decreased the expression of genes related to TMZ resistance. In conclusion, Se@TMZ/Eud-Cs may be an option for the enhancement of TMZ efficiency in GBM treatment.

Purpose: MiR-21 and miR-451 are closely associated with tumor initiation, drug resistance, and recurrence of breast cancer (BC). This study was conducted to evaluate the possible value of the plasma level of miR-21 and miR-451 as potential biomarkers for the detection of primary and recurrent BC. Patients and methods: In this descriptive–analytical study, the plasma level of miR-21 and miR-451 was measured in 23 primary BC patients, 24 recurrent (local/distant metastasis) BC patients, and 24 aged-match women as healthy controls using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Finally, data were analyzed using SPSS software, and the area under the receiver operating characteristic (ROC) curve of miRNAs was measured. Results: The plasma level of miR-21 was significantly increased in both groups of primary (P<0.001) and recurrent (P<0.001) BC patients in comparison with healthy women. However, the plasma level of miR-451 was not significantly changed in primary (P=0.065) and recurrent (P=0.06) BC patients than healthy controls. The elevation of both miR-21 and miR-451 plasma level was not significantly changed in recurrent patients compared with non-recurrent (primary) patients (P=0.481, and P=1, respectively). Based on the ROC analyses, the areas under the curves (AUC) for miR-21 in discriminating primary BC and recurrent BC patients from healthy controls were 0.828 (95% CI: 0.712 to 0.944) and 0.865 (95% CI: 0.756 to 0.974), respectively. Conclusion: These data indicating that plasma miR-21 may be useful as a biomarker for the detection of both primary and recurrent BC. However, plasma miR-451 lacks enough sensitivity in the detection of primary and recurrent BC, and more studies are needed in this area.