AIM: To identify signaling pathways and genes that initiate and commit hepatic stellate cells (HSCs) to transdifferentiation. METHODS: Primary HSCs were isolated from male Sprague-Dawley rats and cultured on plastic f...AIM: To identify signaling pathways and genes that initiate and commit hepatic stellate cells (HSCs) to transdifferentiation. METHODS: Primary HSCs were isolated from male Sprague-Dawley rats and cultured on plastic for 0-10 d. Gene expression was assessed daily (quiescent to day 10 culture-activation) by real time polymerase chain reaction and data clustered using AMADA software. The significance of JAK/STAT signaling to HSC transdifferentiation was determined by treating cells with a JAK2 inhibitor. RESULTS: Genetic cluster analyses, based on expression of these 21 genes, showed similar expression profiles on days 1-3, days 5 and 6, and days 7-10, while freshly isolated cells (day Q) and day 4 cells were genotypically distinct from any of the other days. Additionally, gene expression clustering revealed strong upregulation of interleukin-6, JAK2 and STAT3 mRNA in the early stages of activation. Inhibition of the JAK/STAT signaling pathway impeded the morphological transdifferentiation of HSCs which correlated with decreased mRNA expression of several profibrotic genes including collagens, α-SMA, PDGFR and TGFβR. CONCLUSION: These data demonstrate unique clustered genetic profiles during the daily progression of HSC transdifferentiation and that JAK/STAT signaling may be critical in the early stages of transdifferentiation.展开更多
Circulating cell-free tumor DNA（ctDNA） in the blood is DNA released from apoptotic, circulating, and living tumor cells. ctDNA is about 140 nt in length and has a half-life of about 1.5 h. ctDNA analysis provides a ...Circulating cell-free tumor DNA（ctDNA） in the blood is DNA released from apoptotic, circulating, and living tumor cells. ctDNA is about 140 nt in length and has a half-life of about 1.5 h. ctDNA analysis provides a noninvasive means to assess the genetic profile of cancer in real time. With the advent of molecular technologies, including digital PCR and massively parallel sequencing（MPS）, ctDNA analysis has shown promise as a highly sensitive and specific alternative to conventional tissue biopsy in cancer detection, longitudinal monitoring, and precision therapy. This review provides an overview of the latest development in our understanding of the biologic characteristics, detection methodologies, and potential clinical implications of ctDNA, as well as the challenges in translating ctDNA analysis from the research arena to patient care.展开更多
Biological and clinical advances in the understanding of tumor immunology suggest that immune responsiveness of human tumors is a complex biological phenomenon that could be best studied by a real-time comparison of t...Biological and clinical advances in the understanding of tumor immunology suggest that immune responsiveness of human tumors is a complex biological phenomenon that could be best studied by a real-time comparison of tumor/host interactions in the tumor microenvironment through a high-throughput discovery-driven approach.This conclusion is derived from our recognition that too many hypotheses or,in other words,no solid single hypothesis exist,based on experimental results,to further drive experimentation in human subjects.Functional genomic studies entertained during the last few years consolidated the belief that in humans the interactions between tumor and immune cells are too complex to be approached exclusively with a hypothesis driven method.We believe that immune cells suit cancer cells in a Yin and Yang balance by opposing and yet mutually depending on each other.Indeed,immune infiltration in tumors may play a dual role modulating in different circumstances cancer cell growth or destruction through a physiological modulation of inflammation.It is reasonable to question what induces inflammation at the tumor site.We hypothesize that inflammation is primarily driven by the phenotype of tumor cells that can modulate their microenvironment through cell-to-cell interactions or the secretion of soluble factors.Thus,in analogy the observation of immune cells within tumors parallels the presence of paramedics,police and firemen at the scene of an accident,which is reactive to and not causative of the occurrence.In this review we will explore this hypothesis by reporting and summarizing most of our recent work in the frame of available literature on the subject.Cellular & Molecular Immunology.2004;1(4):256-265.展开更多
基金Supported by National Institutes of Health Grant RO1 AA014891
文摘AIM: To identify signaling pathways and genes that initiate and commit hepatic stellate cells (HSCs) to transdifferentiation. METHODS: Primary HSCs were isolated from male Sprague-Dawley rats and cultured on plastic for 0-10 d. Gene expression was assessed daily (quiescent to day 10 culture-activation) by real time polymerase chain reaction and data clustered using AMADA software. The significance of JAK/STAT signaling to HSC transdifferentiation was determined by treating cells with a JAK2 inhibitor. RESULTS: Genetic cluster analyses, based on expression of these 21 genes, showed similar expression profiles on days 1-3, days 5 and 6, and days 7-10, while freshly isolated cells (day Q) and day 4 cells were genotypically distinct from any of the other days. Additionally, gene expression clustering revealed strong upregulation of interleukin-6, JAK2 and STAT3 mRNA in the early stages of activation. Inhibition of the JAK/STAT signaling pathway impeded the morphological transdifferentiation of HSCs which correlated with decreased mRNA expression of several profibrotic genes including collagens, α-SMA, PDGFR and TGFβR. CONCLUSION: These data demonstrate unique clustered genetic profiles during the daily progression of HSC transdifferentiation and that JAK/STAT signaling may be critical in the early stages of transdifferentiation.
文摘Circulating cell-free tumor DNA（ctDNA） in the blood is DNA released from apoptotic, circulating, and living tumor cells. ctDNA is about 140 nt in length and has a half-life of about 1.5 h. ctDNA analysis provides a noninvasive means to assess the genetic profile of cancer in real time. With the advent of molecular technologies, including digital PCR and massively parallel sequencing（MPS）, ctDNA analysis has shown promise as a highly sensitive and specific alternative to conventional tissue biopsy in cancer detection, longitudinal monitoring, and precision therapy. This review provides an overview of the latest development in our understanding of the biologic characteristics, detection methodologies, and potential clinical implications of ctDNA, as well as the challenges in translating ctDNA analysis from the research arena to patient care.
文摘Biological and clinical advances in the understanding of tumor immunology suggest that immune responsiveness of human tumors is a complex biological phenomenon that could be best studied by a real-time comparison of tumor/host interactions in the tumor microenvironment through a high-throughput discovery-driven approach.This conclusion is derived from our recognition that too many hypotheses or,in other words,no solid single hypothesis exist,based on experimental results,to further drive experimentation in human subjects.Functional genomic studies entertained during the last few years consolidated the belief that in humans the interactions between tumor and immune cells are too complex to be approached exclusively with a hypothesis driven method.We believe that immune cells suit cancer cells in a Yin and Yang balance by opposing and yet mutually depending on each other.Indeed,immune infiltration in tumors may play a dual role modulating in different circumstances cancer cell growth or destruction through a physiological modulation of inflammation.It is reasonable to question what induces inflammation at the tumor site.We hypothesize that inflammation is primarily driven by the phenotype of tumor cells that can modulate their microenvironment through cell-to-cell interactions or the secretion of soluble factors.Thus,in analogy the observation of immune cells within tumors parallels the presence of paramedics,police and firemen at the scene of an accident,which is reactive to and not causative of the occurrence.In this review we will explore this hypothesis by reporting and summarizing most of our recent work in the frame of available literature on the subject.Cellular & Molecular Immunology.2004;1(4):256-265.
