The location and development of Replicon Cluster Domains in early replicating DNA.

: It has been known for many years that in metazoan cells, replication origins are organised into clusters where origins within each cluster fire near-synchronously. Despite clusters being a fundamental organising principle of metazoan DNA replication, the genomic location of origin clusters has not been documented. : We synchronised human U2OS by thymidine block and release followed by L-mimosine block and release to create a population of cells progressing into S phase with a high degree of synchrony.

Pandemic-Era Digital Education: Insights from an Undergraduate Medical Programme.

The undergraduate medical programme at Newcastle University (NU) includes a fundamental 'Essentials of Medical Practice' (EOMP) phase comprising the first 2 years of study. This period is designed to support entrants in their transition from further education into the advanced study and practice of clinical medicine. The anatomical sciences of gross anatomy, histology and embryology, and life sciences including physiology, pharmacology and genetics are key disciplines taught within the integrated case-based EOMP curriculum.

Co-localisation of intra-nuclear membrane type-1 matrix metalloproteinase and hypoxia inducible factor-2α in osteosarcoma and prostate carcinoma cells.

Increased membrane type-1 matrix metalloproteinase (MT1-MMP) expression in osteosarcoma is predictive of poor prognosis and directs bone metastasis in prostate carcinoma. MT1-MMP subcellular localisation varies with oxygen tension, and, therefore, the aim of the present study was to assess protein interactions between MT1-MMP and the hypoxia inducible factors (HIF-1α and HIF-2α). MT1-MMP protein expression was investigated across a panel of cancer cell lines, including a positive and negative control.

TNF-related apoptosis-inducing ligand (TRAIL) for bone sarcoma treatment: Pre-clinical and clinical data.

Bone sarcomas are rare, highly malignant mesenchymal tumours that affect teenagers and young adults, as well as older patients. Despite intensive, multimodal therapy, patients with bone sarcomas have poor 5-year survival, close to 50%, with lack of improvement over recent decades. TNF-related apoptosis-inducing ligand (TRAIL), a member of the tumour necrosis factor (TNF) ligand superfamily (TNFLSF), has been found to induce apoptosis in cancer cells while sparing nontransformed cells, and may therefore offer a promising new approach to treatment.

The High-Affinity Interaction between ORC and DNA that Is Required for Replication Licensing Is Inhibited by 2-Arylquinolin-4-Amines.

In late mitosis and G, origins of DNA replication must be "licensed" for use in the upcoming S phase by being encircled by double hexamers of the minichromosome maintenance proteins MCM2-7. A "licensing checkpoint" delays cells in G until sufficient origins have been licensed, but this checkpoint is lost in cancer cells. Inhibition of licensing can therefore kill cancer cells while only delaying normal cells in G.

Enhanced anti-tumour activity of the combination of the novel MEK inhibitor WX-554 and the novel PI3K inhibitor WX-037.

Purpose: Tumours frequently have defects in multiple oncogenic pathways, e.g. MAPK and PI3K signalling pathways, and combinations of targeted therapies may be required for optimal activity.

Combined PI3K and CDK2 inhibition induces cell death and enhances in vivo antitumour activity in colorectal cancer.

Background: The phosphatidylinositol-3-kinase/mammalian target of rapamycin (PI3K/mTOR) pathway is commonly deregulated in human cancer, hence many PI3K and mTOR inhibitors have been developed and have now reached clinical trials. Similarly, CDKs have been investigated as cancer drug targets.

Methods: We have synthesised and characterised a series of 6-aminopyrimidines identified from a kinase screen that inhibit PI3K and/or mTOR and/or CDK2.

Unreplicated DNA remaining from unperturbed S phases passes through mitosis for resolution in daughter cells.

To prevent rereplication of genomic segments, the eukaryotic cell cycle is divided into two nonoverlapping phases. During late mitosis and G1 replication origins are "licensed" by loading MCM2-7 double hexamers and during S phase licensed replication origins activate to initiate bidirectional replication forks. Replication forks can stall irreversibly, and if two converging forks stall with no intervening licensed origin-a "double fork stall" (DFS)-replication cannot be completed by conventional means.

Chronic p53-independent p21 expression causes genomic instability by deregulating replication licensing.

The cyclin-dependent kinase inhibitor p21(WAF1/CIP1) (p21) is a cell-cycle checkpoint effector and inducer of senescence, regulated by p53. Yet, evidence suggests that p21 could also be oncogenic, through a mechanism that has so far remained obscure. We report that a subset of atypical cancerous cells strongly expressing p21 showed proliferation features.

Pre-clinical use of isogenic cell lines and tumours in vitro and in vivo for predictive biomarker discovery; impact of KRAS and PI3KCA mutation status on MEK inhibitor activity is model dependent.

Studies to identify predictive biomarkers can be carried out in isogenic cancer cell lines, which enable interrogation of the effect of a specific mutation. We assessed the effects of four drugs, the PI3K-mammalian target of rapamycin inhibitor dactolisib, the PI3K inhibitor pictrelisib, and the MEK (MAPK/ERK Kinase) inhibitors PD 0325901 and selumetinib, in isogenic DLD1 parental, KRAS(+/-), KRAS(G13D/-), PIK3CA(+/-) and PIK3CA(E545K/-) colorectal carcinoma cell lines. Importantly, we found substantial differences in the growth of these cells and in their drug sensitivity depending on whether they were studied under 2D (standard tissue culture on plastic) or 3D (in vitro soft agar and in vivo xenograft) conditions.

The enhanced in vivo activity of the combination of a MEK and a PI3K inhibitor correlates with [18F]-FLT PET in human colorectal cancer xenograft tumour-bearing mice.

Combined targeting of the MAPK and PI3K signalling pathways in cancer may be necessary for optimal therapeutic activity. To support clinical studies of combination therapy, 3'-deoxy-3'-[(18)F]-fluorothymidine ([(18)F]-FLT) uptake measured by Positron Emission Tomography (PET) was evaluated as a non-invasive surrogate response biomarker in pre-clinical models. The in vivo anti-tumour efficacy and PK-PD properties of the MEK inhibitor PD 0325901 and the PI3K inhibitor GDC-0941, alone and in combination, were evaluated in HCT116 and HT29 human colorectal cancer xenograft tumour-bearing mice, and [(18)F]-FLT PET investigated in mice bearing HCT116 xenografts.