Glucose-limiting conditions induce an invasive population of MDA-MB-231 breast cancer cells with increased connexin 43 expression and membrane localization

Gap junctional intercellular communication (GJIC) is a homeostatic process mediated by membrane channels composed of a protein family known as connexins. Alterations to channel activity can modulate suppression or facilitation of cancer progression. These varying roles are influenced by the cancer cell genetic profile and the context-dependent mechanisms of a dynamic extracellular environment that encompasses fluctuations to nutrient availability. To better explore the effects of altered cellular metabolism on GJIC in breast cancer, we generated a derivative of the triple-negative breast cancer cell line MDA-MB-231 optimized for growth in low-glucose. Reduced availability of glucose is commonly encountered during tumor development and leads to metabolic reprogramming in cancer cells. MDA-MB-231 low-glucose adapted cells exhibited a larger size with improved cell–cell contact and upregulation of cadherin-11. Additionally, increased protein levels of connexin 43 and greater plasma membrane localization were observed with a corresponding improvement in GJIC activity compared to the parental cell line. Since GJIC has been shown to affect cellular invasion in multiple cancer cell types, we evaluated the invasive qualities of these cells using multiple three-dimensional Matrigel growth models. Results of these experiments demonstrated a significantly more invasive phenotype. Moreover, a decrease in invasion was noted when GJIC was inhibited. Our results indicate a potential response of triple-negative breast cancer cells to reduced glucose availability that results in changes to GJIC and invasiveness. Delineation of this relationship may help elucidate mechanisms by which altered cancer cell metabolism affects GJIC and how cancer cells respond to nutrient availability in this regard. Supplementary materialThe online version of this article (10.1007/s12079-020-00601-3) contains supplementary material, which is available to authorized users.     

Molecular docking analysis of the BRCA1 protein with compounds from Justica adhatoda L

BRCA1 is a human tumour suppression gene. Therefore, it is of interest to document the Molecular docking analysis data of the BRCA1 protein with compounds from Justica adhatoda L (adhatoda). We report that Amrinone, Hexadecanoic acid, Pyrazinamide & Vasicinone have acceptable binding features with the BRCA1 protein for further consideration.     

The porin AaxA protein model from Chlamydia pneumonia

Chlamydophila pneumoniae is an intracellular pathogen accountable for various acute respiratory infections. C. pneumoniae has a gene cluster which encodes a putative outer membrane porin (aaxA), arginine decarboxylase (CPn1032 or aaxB) and a putative cytoplasmic membrane transporter (CPn1031 or aaxC). Therefore, it is of interest to document a molecular protein model of porin AaxA from Chlamydia pneumonia to gain structure to functional insight on the protein.     

Analysis of the development of the lizard, Calotes versicolor. I. A series of normal stages in the embryonic development

It has been shown that the external parameters of eggs of the garden lizard, Calotes versicolor, are not suitable for assessing the exact developmental stages of embryos. In order to make use of this lizard's embryos for experimental work, a series of developmental stages has been characterized, using various morphological features.     

Molecular docking analysis of Enterotoxin I from Staphylococcus aureus with Nafcillin analogues

Staphylococcal enterotoxins (SEs) are liked with food poisoning and other related infections. Nafcillin is an antibiotic used to treat S. aureus. Therefore, it is of interest to study the molecular interactions of 25 nafcillin analogues with enterotoxin I using molecular docking analysis. The analysis shows optimal interaction features of Nafcillin analogues with Enterotoxin I from Staphylococcus aureus for further consideration.     

Cytotoxicity and anti-microbial analysis of silver and graphene oxide bio nanoparticles

It is of interest to document the cytotoxicity and anti microbial analysis of silver and graphene oxide nanoparticles. The plant extracts from Andrographis paniculata and Ocimum sanctum Linn were used as reducing agent. The nanoparticles were characterized using UV-visible spectroscopy, FT-IR, XRD and TEM. The antimicrobial activity was completed for oral pathogens. Brine Shrimp Lethality assay was conducted for cytotoxicity. Thus, we show that silver and graphene oxide bio based nanoparticles have antimicrobial activity with minimum cytotoxic effects.