Cancer is a heavy burden for humans across the world with high morbidity and mortality. Transcription factors including sex determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are thought to be involved in the regulation of specific biological processes. The deregulation of gene expression programs can lead to cancer development. Here, we review the role of the SOX family in breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, brain tumours, gastrointestinal and lung tumours as well as the entailing therapeutic implications. The SOX family consists of more than 20 members that mediate DNA binding by the HMG domain and have regulatory functions in development, cell-fate decision, and differentiation. SOX2, SOX4, SOX5, SOX8, SOX9, and SOX18 are up-regulated in different cancer types and have been found to be associated with poor prognosis, while the up-regulation of SOX11 and SOX30 appears to be favourable for the outcome in other cancer types. SOX2, SOX4, SOX5 and other SOX members are involved in tumorigenesis, e.g. SOX2 is markedly up-regulated in chemotherapy resistant cells. The SoxF family (SOX7, SOX17, SOX18) plays an important role in angio- and lymphangiogenesis, with SOX18 seemingly being an attractive target for anti-angiogenic therapy and the treatment of metastatic disease in cancer. In summary, SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumour microenvironment, and metastasis. Certain SOX proteins are potential molecular markers for cancer prognosis and putative potential therapeutic targets, but further investigations are required to understand their physiological functions.

Summary: Capsular polysaccharide synthesis and virulence in the plant pathogenic bacterium Pantoea stewartii ssp. stewartii requires the quorum‐sensing regulatory proteins, EsaR and EsaI, and the diffusible inducer N‐(3‐oxo‐hexanoyl)‐L‐homoserine lactone. Prior mu‐tational studies suggested that EsaR might function as a repressor of quorum sensing in the control of capsular polysaccharide synthesis. Further, a lux box‐like palindromic sequence coinciding with the putative –10 element of the esaR promoter suggested a possible negative autoregulatory role for EsaR. This report presents genetic evidence that EsaR represses the esaR gene under inducer‐limiting conditions, and that addition of inducer promotes rapid, dose‐dependent derepression. DNA mobility‐shift assays and analyses by surface plasmon resonance refractometry show that EsaR binds target DNAs in a ligand‐free state, and that inducer alters the binding characteristics of EsaR. Physical measurements indicate that the EsaR protein binds N‐(3‐oxo‐hexanoyl)‐L‐homoserine lactone, in a 1:1 protein:ligand ratio, and that inducer binding enhances the thermal stability of the EsaR protein. These combined genetic and biochemical data establish that EsaR regulates its own expression by signal‐independent repression and signal‐dependent derepression. Additionally, we provide evidence that EsaR does not govern the expression of the linked esaI gene, thus EsaR has no role in controlling coinducer synthesis.

The interaction of the two transcriptional regulators RcsA and RcsB with a specific operator is a common mechanism in the activation of capsule biosynthesis in enteric bacteria. We describe RcsAB binding sites in the wza promoter of the operon for colanic acid biosynthesis in Escherichia coliK-12, in the galF promoter of the operon for K2 antigen biosynthesis in Klebsiella pneumoniae, and in thetviA (vipR) promoter of the operon for Vi antigen biosynthesis in Salmonella typhi. We further show the interaction of RcsAB with the rcsA promoters of various species, indicating that rcsA autoregulation also depends on the presence of both proteins. The compilation of all identified RcsAB binding sites revealed the conserved core sequence TaAGaatatTCctA, which we propose to be termed RcsAB box. The RcsAB box is also part ofBordetella pertussis BvgA binding sites and may represent a more distributed recognition motif within the LuxR superfamily of transcriptional regulators. The RcsAB box is essential for the induction of Rcs-regulated promoters. Site-specific mutations of conserved nucleotides in the RcsAB boxes of the E. coli wzaand rcsA promoters resulted in an exopolysaccharide-negative phenotype and in the reduction of reporter gene expression.

Tissue engineering in simulated (s-) and real microgravity (r-μg) is currently a topic in Space medicine contributing to biomedical sciences and their applications on Earth. The principal aim of this review is to highlight the advances and accomplishments in the field of tissue engineering that could be achieved by culturing cells in Space or by devices created to simulate microgravity on Earth. Understanding the biology of three-dimensional (3D) multicellular structures is very important for a more complete appreciation of in vivo tissue function and advancing in vitro tissue engineering efforts. Various cells exposed to r-μg in Space or to s-μg created by a random positioning machine, a 2D-clinostat, or a rotating wall vessel bioreactor grew in the form of 3D tissues. Hence, these methods represent a new strategy for tissue engineering of a variety of tissues, such as regenerated cartilage, artificial vessel constructs, and other organ tissues as well as multicellular cancer spheroids. These aggregates are used to study molecular mechanisms involved in angiogenesis, cancer development, and biology and for pharmacological testing of, for example, chemotherapeutic drugs or inhibitors of neoangiogenesis. Moreover, they are useful for studying multicellular responses in toxicology and radiation biology, or for performing coculture experiments. The future will show whether these tissue-engineered constructs can be used for medical transplantations. Unveiling the mechanisms of microgravity-dependent molecular and cellular changes is an up-to-date requirement for improving Space medicine and developing new treatment strategies that can be translated to in vivo models while reducing the use of laboratory animals.

Recent studies have demonstrated that the rat adipose tissue expresses some of the components necessary for the production of angiotensin II (Ang II) and the receptors mediating its actions. The aim of this work is to characterize the expression of the renin–angiotensin system (RAS) components in perivascular adipose tissue and to assess differences in the expression pattern depending on the vascular bed and type of adipose tissue. We analyzed Ang I and Ang II levels as well as mRNA levels of RAS components by a quantitative RT-PCR method in periaortic (PAT) and mesenteric adipose tissue (MAT) of 3-month-old male Wistar–Kyoto rats. PAT was identified as brown adipose tissue expressing uncoupling protein-1 (UCP-1). It had smaller adipocytes than those from MAT, which was identified as white adipose tissue. All RAS components, except renin, were detected in both PAT and MAT. Levels of expression of angiotensinogen, Ang-converting enzyme (ACE), and ACE2 were similar between PAT and MAT. Renin receptor expression was five times higher, whereas expression of chymase, AT_1a, and AT₂ receptors were significantly lower in PAT compared with MAT respectively. In addition, three isoforms of the AT_1a receptor were found in perivascular adipose tissue. The AT_1b receptor was found at very a low expression level. Ang II levels were higher in MAT with no differences between tissues in Ang I. The results show that the RAS is differentially expressed in white and brown perivascular adipose tissues implicating a different role for the system depending on the vascular bed and the type of adipose tissue.