Testicular tumors are the most common malignancy of young men and tumors affecting the testis are caused by somatic mutations in germ or germ-like cells. The PI3K pathway is constitutively activated in about one third of testicular cancers. To investigate the role of the PI3K pathway in transforming stem-like cells in the testis, we investigated tumors derived from mice with post-natal, constitutive activation of PI3K signaling and homozygous deletion of tumor suppressor Pten, targeted to nestin expressing cells.
View Article and Find Full Text PDFCellular homeostasis is regulated by growth factors (GFs) which orchestrate various cellular processes including proliferation, survival, differentiation, motility, inflammation and angiogenesis. Dysregulation of GFs in microbial infections and malignancies have been reported previously. Viral pathogens exemplify the exploitation of host cell GFs and their signalling pathways contributing to viral entry, virulence, and evasion of anti-viral immune responses.
View Article and Find Full Text PDFThe invasive capacity and progression of glioblastoma cells and neoplastic cells in other are dependent on interactions with the surrounding tumor microenvironment. In particular, cancer cells form a reciprocal relationship with noncellular dysregulated extracellular matrix in the tumors. Here, we describe a protocol that can be used to model the functional relationship between tumor cells and extracellular matrix.
View Article and Find Full Text PDFPhosphorylated histone H2AX (γH2AX) represents a sensitive molecular marker of DNA double-strand breaks (DSBs) and is implicated in stem cell biology. We established a model of mouse embryonic stem cell (mESC) differentiation and examined the dynamics of γH2AX foci during the process. Our results revealed high numbers of γH2AX foci in undifferentiated mESCs, decreasing as the cells differentiated towards the endothelial cell lineage.
View Article and Find Full Text PDFDamage to light-sensing photoreceptors (PRs) occurs in highly prevalent retinal diseases. As humans cannot regenerate new PRs, these diseases often lead to irreversible blindness. Intriguingly, animals, such as the zebrafish, can regenerate PRs efficiently and restore functional vision.
View Article and Find Full Text PDFA critical challenge in the treatment of glioblastoma (GBM) is its highly invasive nature which promotes cell migration throughout the brain and hinders surgical resection and effective drug delivery. GBM cells demonstrate augmented invasive capabilities following exposure to the current gold standard treatment of radiotherapy (RT) and concomitant and adjuvant temozolomide (TMZ), resulting in rapid disease recurrence. Elucidating the mechanisms employed by post-treatment invasive GBM cells is critical to the development of more effective therapies.
View Article and Find Full Text PDFBackground: A subset of meningiomas progress in histopathological grade but drivers of progression are poorly understood. We aimed to identify somatic mutations and copy number alterations (CNAs) associated with grade progression in a unique matched tumour dataset.
Methods: Utilising a prospective database, we identified 10 patients with meningiomas that had undergone grade progression and for whom matched pre- and post-progression tissue (n = 50 samples) was available for targeted next-generation sequencing.
Purpose: Tumor cells thrive by adapting to the signals in their microenvironment. To adapt, cancer cells activate signaling and transcriptional programs and migrate to establish micro-niches, in response to signals from neighboring cells and non-cellular stromal factors. Understanding how the tumor microenvironment evolves during disease progression is crucial to deciphering the mechanisms underlying the functional behavior of cancer cells.
View Article and Find Full Text PDFBrain tumours are the most common solid tumour in children and the leading cause of cancer related death in children. Current treatments include surgery, chemotherapy and radiotherapy. The need for aggressive treatment means many survivors are left with permanent severe disability, physical, intellectual and social.
View Article and Find Full Text PDFGlioblastoma (GBM) is the most prevalent primary central nervous system tumour in adults. The lethality of GBM lies in its highly invasive, infiltrative, and neurologically destructive nature resulting in treatment failure, tumour recurrence and death. Even with current standard of care treatment with surgery, radiotherapy and chemotherapy, surviving tumour cells invade throughout the brain.
View Article and Find Full Text PDFCancer stem cells are defined as low-abundance, quiescent cells and are considered a major cellular source of tumor recurrence following therapy, which identifies these cells as important therapeutic targets for difficult-to-treat cancers, including high-grade gliomas. By contrast to the highly proliferative bulk tumor cells, glioma stem cells (GSC) are slow-cycling, and therefore less sensitive to DNA damaging cytotoxic drugs. GSC are also less reliant on aerobic glycolytic metabolism, leading to inadequate clearing of GSC by chemotherapy and radiotherapy.
View Article and Find Full Text PDFFront Biosci (Landmark Ed)
September 2021
Despite their differences, central nervous system (CNS) tumors and degenerative diseases share important molecular mechanisms underlying their pathologies, due to their common anatomy. Here we review the role of the renin-angiotensin system (RAS) in CNS tumors and degenerative diseases, to highlight common molecular features and examine the potential merits in repurposing drugs that inhibit the RAS, its bypass loops, and converging signaling pathways. The RAS consists of key components, including angiotensinogen, (pro)renin receptor (PRR), angiotensin-converting enzyme 1 (ACE1), angiotensin-converting enzyme 2 (ACE2), angiotensin I (ATI), angiotensin II (ATII), ATII receptor 1 (ATR), ATII receptor 2 (ATR) and the Mas receptor (MasR).
View Article and Find Full Text PDFGlioblastoma (GB) is an aggressive primary brain tumor. Despite intensive research over the past 50 years, little advance has been made to improve the poor outcome, with an overall median survival of 14.6 months following standard treatment.
View Article and Find Full Text PDFThe prognosis for patients with glioblastoma (GBM), the most common and malignant type of primary brain tumour, is very poor, despite current standard treatments such as surgery, radiotherapy and chemotherapy. Moreover, the immunosuppressive tumour microenvironment hinders the development of effective immunotherapies for GBM. Cytokines such as interleukin-10 (IL-10) play a major role in modulating the activity of infiltrating immune cells and tumour cells in GBM, predominantly conferring an immunosuppressive action; however, in some circumstances, IL-10 can have an immunostimulatory effect.
View Article and Find Full Text PDFRecent developments in cancer immunotherapy promise better outcomes for cancer patients, although clinical trials for difficult to treat cancers such as malignant brain cancer present special challenges, showing little response to first generation immunotherapies. Reasons for differences in immunotherapy response in some cancer types are likely due to the nature of tumor microenvironment, which harbors multiple cell types which interact with tumor cells to establish immunosuppression. The cell types which appear to hold the key in regulating tumor immunosuppression are the tumor-infiltrating immune cells.
View Article and Find Full Text PDFGlioblastoma (GBM) is the most prevalent and malignant type of primary brain cancer. The rapid invasion and dissemination of tumor cells into the surrounding normal brain is a major driver of tumor recurrence, and long-term survival of GBM patients is extremely rare. Actin-rich cell membrane protrusions known as invadopodia can facilitate the highly invasive properties of GBM cells.
View Article and Find Full Text PDFThe brain is considered an immune privileged site due to the high selectivity of the blood-brain barrier which restricts the passage of molecules and cells into the brain parenchyma. Recent studies have highlighted active immunosurveillance mechanisms in the brain. Here we review emerging evidence for the contribution of innate lymphoid cells (ILCs) including natural killer (NK) cells to the immunosurveillance of brain cancers focusing on glioblastoma, one of the most aggressive and most common malignant primary brain tumors diagnosed in adults.
View Article and Find Full Text PDFResearch on the role of extracellular vesicles (EVs) in disease pathogenesis has been rapidly growing over the last two decades. As EVs can mediate intercellular communication, they can ultimately facilitate both normal and pathological processes through the delivery of their bioactive cargo, which may include nucleic acids, proteins and lipids. EVs have emerged as important regulators of brain tumors, capable of transferring oncogenic proteins, receptors, and small RNAs that may support brain tumor progression, including in the most common type of brain cancer, glioma.
View Article and Find Full Text PDFPatients with glioblastoma (GB), a highly aggressive brain tumor, have a median survival of 14.6 months following neurosurgical resection and adjuvant chemoradiotherapy. Quiescent GB cancer stem cells (CSCs) invariably cause local recurrence.
View Article and Find Full Text PDFGlioblastoma is a primary tumor of the brain with a poor prognosis. Pathological examination shows that this disease is characterized by intra-tumor morphological heterogeneity, while numerous and ongoing genomic analysis reveals multiple layers of heterogeneity. Intra-tumor and patient-to-patient heterogeneity is underpinned by cellular, genetic, and molecular heterogeneity, which is thought to be key determinants of time to tumor recurrence and resistance to therapy.
View Article and Find Full Text PDFIn cancer, complex intracellular and intercellular signals constantly evolve for the advantage of the tumour cells but to the disadvantage of the whole organism. Decades of intensive research have revealed the critical roles of cellular signalling pathways in regulating complex cell behaviours which influence tumour development, growth and therapeutic response, and ultimately patient outcome. Most studies have focussed on specific pathways and the resulting tumour cell function in a rather linear fashion, partly due to the available methodologies and partly due to the traditionally reductionist approach to research.
View Article and Find Full Text PDFSchwannoma is a peripheral nerve tumour, accounting for 5% of benign soft tissue tumours, with vestibular schwannoma comprising 6% of all intracranial tumours. The tumour stem cell concept is rapidly gaining traction underscoring the understanding of tumourigenesis. It proposes a small subpopulation of primitive cells as the origin of the tumour and these cells account for treatment resistance, local recurrence and distant metastasis in malignant tumours.
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