Objective: National Comprehensive Cancer Network (NCCN) guidelines for cutaneous melanoma (CM) recommend physicians consider increased surveillance for patients who typically have lower melanoma survival rates (stages IIB-IV as determined by the American Joint Committee on Cancer (AJCC), 8th edition). However, up to 15% of patients identified as having a low recurrence risk (stages I-IIA) experience disease recurrence, and some patients identified as having a high recurrence risk will not experience any recurrence. The 31-gene expression profile test (31-GEP) stratifies patient recurrence risk into low (Class 1) and high (Class 2) and has demonstrated risk-appropriate impact on disease management and clinical decisions.
View Article and Find Full Text PDFBackground: There is a need to improve prognostic accuracy for patients with cutaneous melanoma. A 31-gene expression profile (31-GEP) test uses the molecular biology of primary tumors to identify individual patient metastatic risk.
Objective: Develop a nomogram incorporating 31-GEP with relevant clinical factors to improve prognostic accuracy.
Unlabelled: National guidelines recommend sentinel lymph node biopsy (SLNB) be offered to patients with > 10% likelihood of sentinel lymph node (SLN) positivity. On the other hand, guidelines do not recommend SLNB for patients with T1a tumors without high-risk features who have < 5% likelihood of a positive SLN. However, the decision to perform SLNB is less certain for patients with higher-risk T1 melanomas in which a positive node is expected 5%-10% of the time.
View Article and Find Full Text PDFAlzheimer's disease (AD) is characterized by progressive neurodegeneration in the cerebral cortex, histopathologically hallmarked by amyloid β (Aβ) extracellular plaques and intracellular neurofibrillary tangles, constituted by hyperphosphorylated tau protein. Correlation between these pathologic features and dementia has been challenged by the emergence of "nondemented with Alzheimer's neuropathology" (NDAN) individuals, cognitively intact despite displaying pathologic features of AD. The existence of these subjects suggests that some unknown mechanisms are triggered to resist Aβ-mediated detrimental events.
View Article and Find Full Text PDFAlzheimer's disease (AD) is marked by synaptic loss (at early stages) and neuronal death (at late stages). Amyloid beta (Aβ) and tau oligomers can target and disrupt synapses thus driving cognitive decay. Non-demented individuals with Alzheimer's neuropathology (NDAN) are capable of withstanding Aβ and tau toxicity, thus remaining cognitively intact despite presence of AD neuropathology.
View Article and Find Full Text PDFBackground: Adult hippocampal neurogenesis plays an important role in synaptic plasticity and cogntive function. We reported that higher numbers of neural stem cells (NSC) in the hippocampus of cognitively-intact individuals with high Alzheimer's disease (AD) pathology (plaques and tangles) is associated with decreased synaptic amyloid beta oligomers (Aβο), an event linked to onset of dementia in AD. While these findings suggest a link between NSC and synaptic resistance to Aβο, the involved mechanism remains to be determined.
View Article and Find Full Text PDFSome individuals, here referred to as Non-Demented with Alzheimer's Neuropathology (NDAN), retain their cognitive function despite the presence of amyloid plaques and tau tangles typical of symptomatic Alzheimer's disease (AD). In NDAN, unlike AD, toxic amyloid-β oligomers do not localize to the postsynaptic densities (PSDs). Synaptic resistance to amyloid-β in NDAN may thus enable these individuals to remain cognitively intact despite the AD-like pathology.
View Article and Find Full Text PDFRare individuals remain cognitively intact despite the presence of neuropathology usually associated with fully symptomatic Alzheimer's disease (AD), which we refer to as Non-Demented with Alzheimer's disease Neuropathology (NDAN). Understanding the involved mechanism(s) of their cognitive resistance may reveal novel strategies to treat AD-related dementia. In the pursuit of this goal, we determined the number of hippocampal neural stem cells (NSCs) and investigated the expression of several miRNAs in NDAN and AD subjects.
View Article and Find Full Text PDFAlzheimer's disease (AD) is a terminal neurodegenerative disorder that is characterized by accumulation of amyloid plaques and neurofibrillary tangles in the central nervous system. However, certain individuals remain cognitively intact despite manifestation of substantial plaques and tangles consistent with what would be normally associated with fully symptomatic AD. Mechanisms that allow these subjects to escape dementia remain unresolved and understanding such protective biological processes could reveal novel targets for the development of effective treatments for AD.
View Article and Find Full Text PDFIntracellular Ca2+ oscillations are frequently observed during stem cell differentiation, and there is evidence that it may control adipogenesis. The transient receptor potential melastatin 4 channel (TRPM4) is a key regulator of Ca2+ signals in excitable and non-excitable cells. However, its role in human adipose-derived stem cells (hASCs), in particular during adipogenesis, is unknown.
View Article and Find Full Text PDFThe success of nonviral transfection using polymers hinges on efficient nuclear uptake of nucleic acid cargo and overcoming intra- and extracellular barriers. By incorporating PKKKRKV heptapeptide pendent groups as nuclear localization signals (NLS) on a polymer backbone, we demonstrate protein expression levels higher than those obtained from JetPEI and Lipofectamine 2000, the latter being notorious for coupling high transfection efficiency with cytotoxicity. The orientation of the NLS peptide grafts markedly affected transfection performance.
View Article and Find Full Text PDFBackground Aims: Adipose-derived mesenchymal stromal cells (ASCs) are promising tools for delivery of cytotherapy against cancer. However, ASCs can exert profound effects on biological behavior of tumor cells. Our study aimed to examine the influence of ASCs on gene expression and epigenetic methylation profiles of prostate cancer cells as well as the impact of expressing a therapeutic gene on modifying the interaction between ASCs and prostate cancer cells.
View Article and Find Full Text PDFWe have examined the role of a novel cytokine, interleukin-27 (IL-27), in mediating interactions between prostate cancer and bone. IL-27 is the most recently characterized member of the family of heterodimeric IL-12-related cytokines and has shown promise in halting tumor growth and mediating tumor regression in several cancer models, including prostate cancer. Prostate cancer is frequently associated with metastases to the bone, where the tumor induces a vicious cycle of communication with osteoblasts and osteoclasts to induce bone lesions, which are a significant cause of pain and skeletal-related events for patients, including a high fracture risk.
View Article and Find Full Text PDFProstate cancer is frequently associated with bone metastases, where the crosstalk between tumor cells and key cells of the bone microenvironment (osteoblasts, osteoclasts, immune cells) amplifies tumor growth. We have explored the potential of a novel cytokine, interleukin-27 (IL-27), for inhibiting this malignant crosstalk, and have examined the effect of autocrine IL-27 on prostate cancer cell gene expression, as well as the effect of paracrine IL-27 on gene expression in bone and T cells. In prostate tumor cells, IL-27 upregulated genes related to its signaling pathway while downregulating malignancy-related receptors and cytokine genes involved in gp130 signaling, as well as several protease genes.
View Article and Find Full Text PDFElevations in the intracellular Ca(2+) concentration are a phenomena commonly observed during stem cell differentiation but cease after the process is complete. The transient receptor potential melastatin 4 (TRPM4) is an ion channel that controls Ca(2+) signals in excitable and nonexcitable cells. However, its role in stem cells remains unknown.
View Article and Find Full Text PDFWe will focus on the therapeutic applications of ultrasound (US) for gene transfection or 'sonoporation'. Sonoporation therapy or 'sonotherapy' is an emerging physical method for delivering drugs and/or nucleic acids for treating cancer. Because of its non-invasive nature, sonotherapy has the potential to be competitive with other treatment delivery methods such as viruses or lipofection.
View Article and Find Full Text PDFWe have examined the potential of a novel cytokine, interleukin-27 (IL-27), for gene therapy of prostate cancer. IL-27 is the most recently characterized member of the family of heterodimeric IL-12-related cytokines and has shown promise in halting tumor growth and mediating tumor regression in several cancer models. In the present study, we examined the efficacy of a new mode of gene delivery to prostate tumors: low-frequency ultrasound irradiation or "sonoporation.
View Article and Find Full Text PDFAdipose-derived stromal/mesenchymal stem cells (ASC) have gained interest as promising tools for delivering cancer therapy. Adipose tissue can be obtained readily in amounts sufficient for ASC isolation, which can be expanded rapidly, allowing its use at low passage numbers, and can be transduced by viral and nonviral means. Our goal was to examine the potential of ASC to deliver cytokine gene therapies melanoma differentiation associated gene-7 (MDA-7) or pigment epithelial-derived factor (PEDF) to cancer cells.
View Article and Find Full Text PDFIntroduction: We examined whether the novel cell-cycle regulator cdk2-associated protein 1 (p12(cdk2ap1) or cdk2ap1), recently shown to regulate prostate cancer cell cycle and apoptosis, could have the capacity to reduce invasiveness and/or reduce malignant biological interactions between prostate cancer and bone cells. We also examined whether combining two cell-cycle arrest stimuli, cdk2ap1 plus bicalutamide (or casodex, CDX), could help enhance inhibition of prostate cancer cell phenotypes.
Methods: We stably expressed cdk2ap1 in prostate cancer cell lines using lentiviral vectors, as well as several different co-culture assays to quantify cellular invasion, migration, and the effect of the treatments on interaction with the bone microenvironment.
We evaluated the effect of expressing the cell cycle regulator protein cdk2-associating protein1 (cdk2ap1) in inhibiting growth of squamous cell carcinoma (SCC). Expression of cdk2ap1 correlated with reduction in several SCC malignant cell phenotypes, including reduced angiogenesis. We observed several alterations in gene expression consistent with classical functions of cdk2ap1, including upregulation of cell cycle inhibitory genes, and an upregulation in expression of genes belonging to both intrinsic and extrinsic apoptotic cascades.
View Article and Find Full Text PDFBackground: We evaluated the effect of expressing the cell cycle regulator cdk2ap1, downregulated in prostate cancer cell lines, in inhibiting prostate cancer cell growth.
Methods: Expression of cdk2ap1 using a tet-inducible lentiviral system modified growth rate, induced cell cycle arrest and apoptosis and reduced the invasive ability of prostate cancer cell lines, as assayed by cell viability, cell cycle profiling, Caspase 3/7 detection, and matrigel invasion assays. We examined the effect of expressing cdk2ap1 on gene expression profiles of cytokine, invasion, apoptotic, and androgen response pathways using quantitative real-time PCR, and used androgen-responsive reporter gene assays, and methylation-sensitive PCR to examine the mechanism of cdk2ap1 interaction with androgen-responsive pathways.
We evaluated the effect of expressing the cell cycle regulator cdk2ap1 in epithelial or stromal cell compartments to reduce SCC growth in vitro and in vivo. Cell-autonomous and/or non-cell-autonomous expression of cdk2ap1 reduced tumor growth and invasion and altered cell cycle, adhesion, invasion, angiogenesis, and apoptotic gene expression, as assessed by several in vitro phenotype assays, quantitative real-time PCR, and in vivo molecular imaging using a novel three-way xenograft animal model. Our findings suggest that the interactions between cancer cells and fibroblasts that promote abnormal growth can be minimized by expressing cdk2ap1, supporting a novel concept by which tumor/growth suppressor genes can impact tumorigenesis phenotypes from non-cell-autonomous interactions within the tumor microenvironment.
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