DNA Binding and Anticancer Properties of New Pd(II)-Phosphorus Schiff Base Metal Complexes

DNA has become the target of metal complexes in cancer drug discovery. Due to the side effects of widely known cisplatin and its derivative compounds, alternative metal-based drug discovery studies are still ongoing. In this study, the DNA-binding ability of Pd(II) and Pt(II) complexes of four phosphorus Schiff base ligands and four hydrazonoic-phosphines are investigated by using in silico analyses. Phosphorus Schiff base-Pd(II) complexes encoded as B1 and B2 with the best DNA-binding potential are synthesized and characterized. The DNA-binding potentials of these two new Pd(II) complexes are also investigated experimentally, and their antitumor properties are demonstrated in vitro in A549, MCF7, HuH7, and HCT116 cancer cells. The mechanisms of these metal complexes that kill the cells mentioned above in different activities are elucidated by flow cytometry apoptosis analysis and colony formation analysis The in silico binding energies of these two new palladium complexes ΔG (B1): −4.51 and ΔG (B2): −6.04 kcal/mol, and their experimental DNA-binding constants were found as Kb (B1): 4.24 × 10⁵, Kb (B2): 4.98 × 10⁵). The new complexes, which show different antitumor effects in different cells, are the least effective in HuH7 liver cells, while they showed the best antitumor properties in HCT116 colon cancer cells.

Slug and Vimentin downregulation at the metastatic site is associated with Skip-N2 metastasis of lung adenocarcinoma

OBJECTIVE

Lung cancer displays heterogeneity both in the tumor itself and in its metastatic regions. One interesting behavior of the tumor is known as Skip N2 metastasis, which N2 lymph nodes contain tumor cells while N1 are clean. In this study, mRNA levels of epithelial mesenchymal transition (EMT) related genes in skip N2 and normal N2 involvements of non-small cell lung cancer tissues were investigated to evaluate the possible molecular background that may contribute to the pathogenesis of Skip N2 metastasis.

MATERIALS AND METHODS

Eighty-three surgically resected and paraffin embedded lymph node samples of lung cancer patients were analyzed in this study, which 40 of them were Skip N2. N2 tissues were sampled from 50% tumor containing areas and total RNA was extracted. mRNA levels for 18S, E-cadherin, Vimentin, ZEB1 and SLUG were analyzed via qPCR and E-cadherin and vimentin protein levels via immunohistochemistry (IHC). Bioinformatic analysis were adopted using online datasets to evaluate significantly co-expressed genes with SLUG in lung cancer tissue samples.

RESULTS

Skip-N2 patients who had adenocarcinoma subtype had better survival rates. Comparative analysis of PCR results indicated that Skip N2 tumor tissues had increased E-Cadherin/Vimentin ratio and ZEB1 mRNA expression, and significantly decreased levels of SLUG. E-cadherin IHC staining were higher in Skip N2 and Vimentin were in Non-Skip N2. TP63 had a strong correlation with SLUG expression in the bioinformatics analyses.

CONCLUSION

The results indicate that, at molecular level, Skip N2 pathogenesis has different molecular background and regulation of SLUG expression may orchestrate the process.

Discovery of new chiral sulfonamides bearing benzoxadiazole as HIF inhibitors for non-small cell lung cancer therapy: design, microwave-assisted synthesis, binding affinity, in vitro antitumoral activities and in silico studies

Thirty-four chiral compounds having benzoxadiazole and sulfonamide moieties on the skeleton have been synthesized. The in vitro cytotoxic activity and apoptotic effects of these compounds have been evaluated using the A549 lung cancer cell line.

Favipiravir: insight into the crystal structure, Hirshfeld surface analysis and computational study

In this work we report structural and computational studies of favipiravir, which is now used as a drug for COVID-19 treatment. The molecule is completely flat and stabilized by an intramolecular O–H···O hydrogen bond, yielding a six-membered pseudo-aromatic ring. The aromaticity index of this pseudo-aromatic ring was found to be 0.748, while the same indix for the pyrazine ring in favipiravir was found to be 0.954. The crystal packing of favipiravir is mainly constructed through intermolecular N–H···O, N–H···N and C–H···O hydrogen bonds, yielding a 3D supramolecular framework with a zst topology defined by the point symbol of (6⁵·8). The crystal structure of favipiravir is further stabilized by weak C–F···F–C intermolecular type II dihalogen interactions, yielding a 1D supramolecular polymeric chain. More than 80% of the total Hirshfeld surface area for favipiravir is occupied by H···H/C/N/O/F and C···N/O contacts. Energy frameworks have been calculated to additionally analyze the overall crystal packing. It was established that the structure of favipiravir is mainly characterized by the dispersion energy framework followed by the less significant electrostatic energy framework contribution. Finally, by using density functional theory (DFT) calculations and the quantum theory of atoms in molecules, we have assigned the interaction energy of each hydrogen bond, which can be helpful to develop scoring functions to be used in force fields/docking calculations.

COVID-19 patients' sera induce epithelial mesenchymal transition in cancer cells

Covid-19 Pneumonia of SARS-CoV-2 pandemic infection, persists to have high disease burden especially in cancer patients. Increased inflammation and thromboembolic processes are blamed to influence cancer patients more than the others but due to lack of knowledge regarding the pathophysiology of the both the virus itself and the response of the host, more basic and translational disease modeling research is needed to understand Cancer-Covid-19 interaction. In this study, serum samples from the patients, who were hospitalized due to Covid-19 pneumonia, applied to different cancer cells and cytotoxicity, motility, proliferation and gene expression analysis were performed. Serum samples derived from healthy volunteers and the fetal bovine serum that is used regularly in cell culture experiments used as controls. Hospitalized Covid-19 patients who had also cancer, were retrospectively screened, and their clinical course were recorded. Overall 12 Patient (PS) and 4 healthy serums (CS) were included in the experiments. PS applied cells showed increased motility in A549 cells as well as lost cell to cell connection in MCF7 and HCT116 cells, and induced expression of VIM, ZEB1 and SNAIL2 mRNA levels. Eight cancer diagnosed patients who were hospitalized due to Covid-19 between April and September 2020 were also reviewed retrospectively, which 5 of them were dead during SARS-CoV-2 infection. Thorax CT images of the 2 patients showed increased metastatic nodules in the lungs as of January 2021. The results of the study indicate that metastasis may be one of the prolonged consequences of COVID-19 pandemic in cancer sufferers.

Antitumor effects of novel nickel–hydrazone complexes in lung cancer cells

Two novel nickel(ii) complexes [NiL^I]·CH₃CN (1·CH₃CN) and [Ni(H₂L^II)(NCS)₂]·0.5H₂O (2·0.5H₂O) were fabricated and in in vitro experiments they both showed the dose dependent cytotoxicity and killed A549 lung cancer cells via an apoptotic pathway.

Protein Phosphatase 1-Targeting Small-Molecule C31 Inhibits Ebola Virus Replication

Background

Ebola virus (EBOV) infection causes severe hemorrhagic fever. EBOV transcription is controlled by host protein phosphatase 1 (PP1), which dephosphorylates VP30 protein. We previously developed 1E7-03, a compound targeting a noncatalytic site of PP1 that induced VP30 phosphorylation and inhibited EBOV transcription. Here, we attempted to further improve 1E7-03, which was not stable in murine serum.

Results

High-throughput screening with EBOV-green fluorescent protein was conducted on 72 1E7-03 analogs and identified 6 best inhibitory and the least toxic compounds. A parallel in silico screening of compounds from the ZINC database by docking to PP1 identified the best-binding compound C31, which was also present among the top 6 compounds found in the viral screen. C31 showed the best EBOV inhibitory activity among the top 6 compounds and also inhibited EBOV minigenome. C31 bound to the PP1 C-terminal groove in vitro and increased VP30 phosphorylation in cultured cells. C31 demonstrated improved stability in mouse plasma and cell permeability, compared with 1E7-03. It was also detected for 24 hours after injection in mice.

Conclusion

C31 represents a novel PP1-targeting EBOV inhibitor with improved pharmacological properties that can be further evaluated for future antifiloviral therapy.

The frequency of diastolic dysfunction in patients with sarcoidosis and it's relationship with HLA DRB1* alleles

BACKGROUND

Impaired systolic function is common in sarcoidosis however the frequency of diastolic dysfunction (DD) and it's possible genetic basis has not been fully elucidated yet. The aim of this study is to evaluate the frequency of left ventricular DD(LVDD) and right ventricular DD(RVDD) and it's possible relationship between Human Leukocyte Antigen(HLA)-DRB1* alleles in patients with sarcoidosis.

METHODS

Seventy seven patients (51 females, mean age 41.1±8.2yrs) without known sarcoid related or any other structured heart disease and 77 healthy controls with a similar age and gender (38.7±7.8yrs,51 females) were included in the case control study. DD was diagnosed with echocardiography. RVDD was defined as early(E)/late(A) ratio<1 or >2 on tricuspit valve. LVDD was defined as E/A ratio<1 or >2 on mitral valve, with isovolumetric relaxation time(IVRT)>90 miliseconds(msn) or deceleration rate of early diastolic flow(Edec)>220msn respectively. All patients were HLAtyped with the Sequence Specific Oligonucleotide Probe(SSOP) method.

RESULTS

The frequencies of LVDDs and RVDDs were significantly higher in sarcoidosis patients than the controls (26.0% vs. 2.6% for LVDD; and 42.9% vs. 18.2% for RVDD)(p<0.05). No significant difference was found in patients according to the presence of RVDD and LVDD in terms of age, gender or respiratory function test parameters. Although the frequency of HLA DRB1* alleles were comparable among patients with RVDD, HLA DRB1*14 alleles were more frequent in patients with LVDD.

CONCLUSIONS

Biventricular DD is common in patients with sarcoidosis without manifest cardiac involvement. HLA DRB1*14 allele seems to be related with LVDD in this study population.