The 6MW declines significantly after two cycles of chemotherapy. This decline may have been even greater as patients with lower 6MW were more likely to drop out of the study. An initial 6MW > or =400 m might be a useful prognostic factor for survival in patients with advanced non-small cell lung cancer.

Expression of a few master transcription factors can reprogram the epigenetic landscape and three-dimensional chromatin topology of differentiated cells and achieve pluripotency. During reprogramming, thousands of long-range chromatin contacts are altered, and changes in promoter association with enhancers dramatically influence transcription. Molecular participants at these sites have been identified, but how this re-organization might be orchestrated is not known. Biomolecular condensation is implicated in subcellular organization, including the recruitment of RNA polymerase in transcriptional activation. Here, we show that reprogramming factor KLF4 undergoes biomolecular condensation even in the absence of its intrinsically disordered region. Liquid–liquid condensation of the isolated KLF4 DNA binding domain with a DNA fragment from the NANOG proximal promoter is enhanced by CpG methylation of a KLF4 cognate binding site. We propose KLF4-mediated condensation as one mechanism for selectively organizing and re-organizing the genome based on the local sequence and epigenetic state.

Microvascular injury and increased vascular leakage are prominent features of radiation-induced lung injury (RILI), and often follow cancer-associated thoracic irradiation. Our previous studies demonstrated that polymorphisms in the gene (MIF) encoding macrophage migratory inhibition factor (MIF), a multifunctional pleiotropic cytokine, confer susceptibility to acute inflammatory lung injury and increased vascular permeability, particularly in senescent mice. In this study, we exposed wild-type and genetically engineered mif 2/2 mice to 20 Gy single-fraction thoracic radiation to investigate the agerelated role of MIF in murine RILI (mice were aged 8 wk, 8 mo, or 16 mo). Relative to 8-week-old mice, decreased MIF was observed in bronchoalveolar lavage fluid and lung tissue of 8-to 16-month-old wild-type mice. In addition, radiated 8-to 16-month-old mif 2/2 mice exhibited significantly decreased bronchoalveolar lavage fluid total antioxidant concentrations with progressive age-related decreases in the nuclear expression of NF-E2-related factor-2 (Nrf2), a transcription factor involved in antioxidant gene up-regulation in response to reactive oxygen species. This was accompanied by decreases in both protein concentrations (NQO1, GCLC, and heme oxygenase-1) and mRNA concentrations (Gpx1, Prdx1, and Txn1) of Nrf2-influenced antioxidant gene targets. In addition, MIF-silenced (short, interfering RNA) human lung endothelial cells failed to express Nrf2 after oxidative (H 2 O 2 ) challenge, an effect reversed by recombinant MIF administration. However, treatment with an antioxidant (glutathione reduced ester), but not an Nrf2 substrate (N-acetyl cysteine), protected aged mif 2/2 mice from RILI. These findings implicate an important role for MIF in radiation-induced changes in lung-cell antioxidant concentrations via Nrf2, and suggest that MIF may contribute to age-related susceptibility to thoracic radiation.

The crystal structure of chikungunya (CHIKV) virus capsid protease domain has been determined at 2.2Å. Structure reveals a chymotrypsin-like protease fold with a conserved hydrophobic pocket in CHIKV capsid protein (CP) for interaction with the cytoplasmic tail of E2 (cdE2) similar to the capsid protein of other alphaviruses. Molecular contacts between CP-cdE2 were determined by fitting structures of CHIKV CP and cdE2 into the cryo-EM map of Venezuelan equine encephalitis virus (VEEV). Binding of (S)-(+)-Mandelic acid (MDA) and Ethyl 3-aminobenzoate (EAB) to the hydrophobic pocket of CP was evaluated by molecular docking. Surface plasmon resonance (SPR) and fluorescence spectroscopy experiments confirmed MDA and EAB binding to the CP. The binding constants (K) obtained from SPR for MDA and EAB were 1.2 × 10 M and 0.2 × 10 M, respectively. This study adds to the understanding of chikungunya virus structural proteins and may serve as the basis for antiviral development against chikungunya disease.

The protein-protein interactions (PPIs) of the transmembrane glycoprotein E2 with the hydrophobic pocket on the surface of capsid protein (CP) plays a critical role in alphavirus life cycle. Dioxane based derivatives targeting PPIs have been reported to possess antiviral activity against Sindbis Virus (SINV), the prototype alphavirus. In this study, the binding of picolinic acid (PCA) to the conserved hydrophobic pocket of capsid protein was analyzed by molecular docking, isothermal titration calorimetry (ITC), surface plasmon resonance (SPR) and fluorescence spectroscopy. The binding constant KD obtained for PCA was 2.1×10(-7)M. Additionally, PCA significantly inhibited CHIKV replication in infected Vero cells, decreasing viral mRNA and viral load as assessed by qRT-PCR and plaque reduction assay, respectively. This study is suggestive of the potential of pyridine ring compounds as antivirals against alphaviruses and may serve as the basis for the development of PCA based drugs against alphaviral diseases.

Bromodomain testis (BRDT), a member of the bromodomain and extraterminal (BET) subfamily that includes the cancer targets BRD2, BRD3, and BRD4, is a validated contraceptive target. All BET subfamily members have two tandem bromodomains (BD1 and BD2). Knockout mice lacking BRDT-BD1 or both bromodomains are infertile. Treatment of mice with JQ1, a BET BD1/BD2 nonselective inhibitor with the highest affinity for BRD4, disrupts spermatogenesis and reduces sperm number and motility. To assess the contribution of each BRDT bromodomain, we screened our collection of DNA-encoded chemical libraries for BRDT-BD1 and BRDT-BD2 binders. High-enrichment hits were identified and resynthesized off-DNA and examined for their ability to compete with JQ1 in BRDT and BRD4 bromodomain AlphaScreen assays. These studies identified CDD-1102 as a selective BRDT-BD2 inhibitor with low nanomolar potency and >1,000-fold selectivity over BRDT-BD1. Structure–activity relationship studies of CDD-1102 produced a series of additional BRDT-BD2/BRD4-BD2 selective inhibitors, including CDD-1302, a truncated analog of CDD-1102 with similar activity, and CDD-1349, an analog with sixfold selectivity for BRDT-BD2 versus BRD4-BD2. BROMOscan bromodomain profiling confirmed the great affinity and selectivity of CDD-1102 and CDD-1302 on all BET BD2 versus BD1 with the highest affinity for BRDT-BD2. Cocrystals of BRDT-BD2 with CDD-1102 and CDD-1302 were determined at 2.27 and 1.90 Å resolution, respectively, and revealed BRDT-BD2 specific contacts that explain the high affinity and selectivity of these compounds. These BD2-specific compounds and their binding to BRDT-BD2 are unique compared with recent reports and enable further evaluation of their nonhormonal contraceptive potential in vitro and in vivo.

Chikungunya virus (CHIKV) capsid protein (CVCP) is a serine protease that possesses cis-proteolytic activity essential for the structural polyprotein processing and plays a key role in the virus life cycle. CHIKV being an emerging arthropod-borne pathogenic virus, is a public health concern worldwide. No vaccines or specific antiviral treatment is currently available for chikungunya disease. Thus, it is important to develop inhibitors against CHIKV enzymes to block key steps in viral reproduction. In view of this, CVCP was produced recombinantly and purified to homogeneity. A fluorescence resonance energy transfer (FRET)-based proteolytic assay was developed for high throughput screening (HTS). A FRET peptide substrate (DABCYL-GAEEWSLAIE-EDANS) derived from the cleavage site present in the structural polyprotein of CVCP was used. The assay with a Z’ factor of 0.64 and coefficient of variation (CV) is 8.68% can be adapted to high throughput format for automated screening of chemical libraries to identify CVCP specific protease inhibitors. Kinetic parameters Km and kcat/Km estimated using FRET assay were 1.26 ± 0.34 μM and 1.11 × 103 M−1 sec−1 respectively. The availability of active recombinant CVCP and cost effective fluorogenic peptide based in vitro FRET assay may serve as the basis for therapeutics development against CHIKV.

: Cancer patients are more susceptible for COVID-19; however, the prevalence of COVID-19 in different types of cancer is still inconsistent and inconclusive. Here, we delineate the intricate relationship between breast cancer and COVID-19. Breast cancer and COVID-19 share involvement of common comorbidities, hormonal signalling pathways, gender differences, rennin-angiotensin system (RAS), angiotensin-converting enzyme-2 (ACE-2), transmembrane protease serine 2 (TMPRSS2) and dipeptidyl peptidase-IV (DPP-IV). We also shed light on the possible effects of therapeutic modalities of COVID-19 on breast cancer outcomes. Briefly, we conclude that breast cancer patients are more susceptible for COVID-19 in comparison with their normal counterparts. Women are more resistant for the occurrence and severity of COVID-19. Increased expression of ACE2 and TMPRSS2 are being correlated with occurrence and severity of COVID-19, but higher expression of ACE2 and lower expression of TMPRSS2 are prognostic markers for overall and disease free survival in breast cancer. The ACE2 inhibitors and ibuprofen therapies for COVID-19 treatment may aggravate the clinical condition of the breast cancer patients through chemo-resistance and metastasis. Most of the available therapeutic modalities for COVID-19 were also found to exert positive effects on breast cancer outcomes. Besides drugs in clinical trend, TMPRSS2 inhibitors, estrogen supplementation, androgen deprivation and DPP-IV inhibitors may also be used to treat breast cancer patients infected with SARS-CoV-2. However, drug-drug interactions suggest that some of the drugs used for the treatment of COVID-19 may modulate the drug metabolism of anticancer therapies which may leads to adverse drug reaction events.