Early Stages Of Transformation Research Articles

IT Based Business Transformation Research of XLY

Under the impact of mobile e-commerce, traditional supermarket operations are facing greater competitive pressure. Many traditional supermarkets are looking for a way out, relying on their accumulated supply chain, customer base, and brand capabilities to transform into e-commerce channels. XYL is a department store retailing company, has also followed the needs of the times and embarked on the road of digital transformation, opening an online store, and realizing online and offline integration. However, XYL is still in the early stage of transformation and still faces many problems such as long delivery time. This report focuses on the problem of late delivery of goods in XYL, through identify the process most relevant to the problem and diagnose problems in the current process to provide suggestions for the redesign and implementation of the process.

University of Patras: A "Green" University? A Case Study of a Greek University Institution

The unprecedented intensity of climate change shows how urgent the need to make our societies more sustainable is. It is therefore positive that many enterprises and educational organizations worldwide are making efforts to integrate the principles of sustainable development into their way of operating. The aim of this article is to highlight the research findings on the actions and processes adopted in a Greek university, the University of Patras, to promote sustainability and ‘green’ operation. It is a qualitative survey conducted at the University of Patras with the participation of 13 professors of the university as the key - actors as they: a) teach relevant courses, b) participate in relevant actions, c) hold (at the time of the research) positions of responsibility in the leadership of the university. By generating the data, through the use of thematic analysis of official university texts and semi-structured interviews it is concluded that this university is in an early stage of transformation to a green operating model.

EYGFPuv-Assisted Transgenic Selection in Populus deltoides WV94 and Multiplex Genome Editing in Protoplasts of P. trichocarpa × P. deltoides Clone '52-225'.

Although CRISPR/Cas-based genome editing has been widely used for plant genetic engineering, its application in the genetic improvement of trees has been limited, partly because of challenges in Agrobacterium-mediated transformation. As an important model for poplar genomics and biotechnology research, eastern cottonwood (Populus deltoides) clone WV94 can be transformed by A. tumefaciens, but several challenges remain unresolved, including the relatively low transformation efficiency and the relatively high rate of false positives from antibiotic-based selection of transgenic events. Moreover, the efficacy of CRISPR-Cas system has not been explored in P. deltoides yet. Here, we first optimized the protocol for Agrobacterium-mediated stable transformation in P. deltoides WV94 and applied a UV-visible reporter called eYGFPuv in transformation. Our results showed that the transgenic events in the early stage of transformation could be easily recognized and counted in a non-invasive manner to narrow down the number of regenerated shoots for further molecular characterization (at the DNA or mRNA level) using PCR. We found that approximately 8.7% of explants regenerated transgenic shoots with green fluorescence within two months. Next, we examined the efficacy of multiplex CRISPR-based genome editing in the protoplasts derived from P. deltoides WV94 and hybrid poplar clone '52-225' (P. trichocarpa × P. deltoides clone '52-225'). The two constructs expressing the Trex2-Cas9 system resulted in mutation efficiency ranging from 31% to 57% in hybrid poplar clone 52-225, but no editing events were observed in P. deltoides WV94 transient assay. The eYGFPuv-assisted plant transformation and genome editing approach demonstrated in this study has great potential for accelerating the genome editing-based breeding process in poplar and other non-model plants species and point to the need for additional CRISPR work in P. deltoides.

Red fluorescence protein (DsRed2) promotes the screening efficiency in peanut genetic transformation.

Peanut (Arachis hypogaea L.), one of the leading oilseed crops worldwide, is an important source of vegetable oil, protein, minerals and vitamins. Peanut is widely cultivated in Asia, Africa and America, and China is the largest producer and consumer of peanut. Genetic engineering has shown great potential to alter the DNA makeup of an organism which is largely hindered by the low transformation and screening efficiency including in peanut. DsRed2 is a reporter gene widely utilized in genetic transformation to facilitate the screening of transformants, but never used in peanut genetic transformation. In this study, we have demonstrated the potential of the red fluorescence protein DsRed2 as a visual reporter to improve screening efficiency in peanut. DsRed2 was firstly expressed in protoplasts isolated from peanut cultivar Zhonhua 12 by PEG, and red fluorescence was successfully detected. Then, DsRed2 was expressed in peanut plants Zhonghua 12 driven by 35S promoter via Agrobacterium tumefaciens-mediated transformation. Red fluorescence was visually observed in calli and regenerated shoots, as well as in roots, leaves, flowers, fresh pod shells and mature seeds, suggesting that transgenic screening could be initiated at the early stage of transformation, and continued to the progeny. Upon screening with DsRed2, the positive plant rate was increased from 56.9% to 100%. The transgenic line was then used as the male parent to be crossed with Zhonghua 24, and the hybrid seeds showed red fluorescence as well, indicating that DsRed2 could be applied to hybrid plant identification very efficiently. DsRed2 was also expressed in hairy roots of Huayu 23 via Agrobacterium rhizogenes-mediated transformation, and the transgenic roots were easily selected by red fluorescence. In summary, the DsRed2 is an ideal reporter to achieve maximum screening efficiency and accuracy in peanut genetic transformation.

Development of Human Adrenocortical Adenoma (HAA1) Cell Line from Zona Reticularis

The human adrenal cortex is composed of distinct zones that are the main source of steroid hormone production. The mechanism of adrenocortical cell differentiation into several functionally organized populations with distinctive identities remains poorly understood. Human adrenal disease has been difficult to study, in part due to the absence of cultured cell lines that faithfully represent adrenal cell precursors in the early stages of transformation. Here, Human Adrenocortical Adenoma (HAA1) cell line derived from a patient's macronodular adrenocortical hyperplasia and was treated with histone deacetylase inhibitors (HDACis) and gene expression was examined. We describe a patient-derived HAA1 cell line derived from the zona reticularis, the innermost zone of the adrenal cortex. The HAA1 cell line is unique in its ability to exit a latent state and respond with steroidogenic gene expression upon treatment with histone deacetylase inhibitors. The gene expression pattern of differentiated HAA1 cells partially recreates the roster of genes in the adrenal layer that they have been derived from. Gene ontology analysis of whole genome RNA-seq corroborated increased expression of steroidogenic genes upon HDAC inhibition. Surprisingly, HDACi treatment induced broad activation of the Tumor Necrosis Factor (TNF) alpha pathway. This novel cell line we developed will hopefully be instrumental in understanding the molecular and biochemical mechanisms controlling adrenocortical differentiation and steroidogenesis.

Single-Cell RNA Sequencing Reveals the Characteristics of High Proliferating Tumor Cells in Btki-Resistant Progression to Richter Transformation and Accelerated CLL

Introduction Richter transformation (RT) and "accelerated” CLL (aCLL) were both regarded as the aggressive manifestation of CLL. The underlying mechanisms of such aggressive transformation has not been fully disclosed yet, especially transformed after novel targeted agents like BTK inhibitors. Moreover, cases reported that aCLL was observed with subsequent transformation of diffuse large B cell lymphoma (DLBCL) and aCLL may represent an early stage of transformation. However, such clinical observations lack biological evidence to compare the similarities and differences between aCLL and RT. Methods Single-cell RNA sequencing (scRNA-seq) of paired lymph node (LN) and peripheral blood (PB) was performed among 2 RT (P1, P2) and 2 aCLL (P3, P4) patients (pathologically diagnosed in LN) and bioinformatics analysis was conducted. Patient 1 and Patient 2 were initially treated with BTK inhibitors (P1 ibrutinib for 3 months and P2 zanubrutinib for 19 months) and then progressed to RT. Patient 3 was initially diagnosed as aCLL and Patient 4 was treated with zanubrutinib for 54 months and then progressed to aCLL. Results Identification of cell types in 4 patients showed great heterogeneity. Higher proportion of proliferative tumor with cells at either the G2/M or S phase was found in two RT patients than in two aCLL patients. Single-cell trajectory construction was done using "monocle 2” inferred tumor development and differentiation among each patient. Tumor cells from PB were distributed in the front of trajectories, indicating that the progressive LNs were evolved from PB indolent CLL cells. Moreover, among three patients progressing from BTK inhibitors (BTKi), highly proliferative tumor cells were enriched in the end of trajectories, indicating their resistant characteristics to BTKi. Single-cell GSEA (ssGSEA) analysis showed that pathways of spliceosome, MYC targets, mTORC1, epigenetics, DNA repair, glycolysis and oxidative phosphorylation were significantly activated in those proliferative tumor cells enriched in the end of trajectories while remained inactivation in treatment-naïve tumor cells, comprehensively leading to resistance to BTKi treatment. Although zanubrutinib-resistant aCLL of P4 showed relatively lower proportion of highly proliferative tumor cells than RT patients, they shared common biological characters and could be regarded as the early phase of RT. InferCNV analysis was performed and UPhyloplot2 was used to construct the copy number gain and loss evolution. Notably, 6p copy number gain has lost in the end of CNV tree which was enriched in highly proliferative tumor cells of RT while such phenomenon has not been found in two aCLL patients. The involved genes in this 6p CNV region were screened and we found significant enrichment of MHC Class I and Class II genes. The expression of such MHC Class I and Class II genes were also showed gradual downregulation in thoese highly proliferative tumor cells in RT, indicating their escape from immune surveillance. Moreover, exhaustion T cells also showed significantly higher proportion in LNs of RT than LNs of aCLL, indicating the exhausted immune environment of RS. Conclusion scRNA-seq analysis showed that highly proliferative tumor cells in BTKi-resistant progression to RT and aCLL showed common cell cycle, glycolysis, oxidative phosphorylation, spliceosome, epigenetics and MYC targeted activation. BTKi-resistant progression to aCLL could be regarded as an early phase of RT. Moreover, RT exhibited more exhausted immune microenvironment and significant downregulation of antigen presentation, indicating that combination of immune checkpoint inhibitors might be of clinical significance in RT treatment. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Artificial intelligence-assisted mapping of proliferation centers allows the distinction of accelerated phase from large cell transformation in chronic lymphocytic leukemia

AbstractChronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) is characterized morphologically by numerous small lymphocytes and pale nodules composed of prolymphocytes and paraimmunoblasts known as proliferation centers (PCs). Patients with CLL can undergo transformation to a more aggressive lymphoma, most often diffuse large B-cell lymphoma (DLBCL), known as Richter transformation (RT). An accelerated phase of CLL (aCLL) also may be observed which correlates with subsequent transformation to DLBCL, and may represent an early stage of transformation. Distinguishing PCs in CLL from aCLL or RT can be diagnostically challenging, particularly in small needle biopsy specimens. Available guidelines pertaining to distinguishing CLL from its' progressive forms are limited, subject to the morphologist's experience and are often not completely helpful in the assessment of scant biopsy specimens. To objectively assess the extent of PCs in aCLL and RT, and enhance diagnostic accuracy, we sought to design an artificial intelligence (AI)-based tool to identify and delineate PCs based on feature analysis of the combined individual nuclear size and intensity, designated here as the heat value. Using the mean heat value from the generated heat value image of all cases, we were able to reliably separate CLL, aCLL and RT with sensitive diagnostic predictive values.

Should mutant TP53 be targeted for cancer therapy?

Mutations in the TP53 tumour suppressor gene are found in ~50% of human cancers [1-6]. TP53 functions as a transcription factor that directly regulates theexpression of ~500 genes, some of them involved in cell cycle arrest/cell senescence, apoptotic cell death or DNA damage repair, i.e. the cellular responses that together prevent tumorigenesis [1-6]. Defects in TP53 function not only cause tumour development but also impair the response of malignant cells to anti-cancer drugs, particularly those that induce DNA damage [1-6]. Most mutations in TP53 in human cancers cause a single amino acid substitution, usually within the DNA binding domain of the TP53 protein. These mutant TP53 proteins are often expressed at high levels in the malignant cells. Three cancer causing attributes have been postulated for mutant TP53 proteins: the inability to activate target genes controlled by wt TP53 (loss-of-function, LOF) that are critical for tumour suppression, dominant negative effects (DNE), i.e. blocking the function of wt TP53 in cells during early stages of transformation when mutant and wt TP53 proteins are co-expressed, and gain-of-function (GOF) effects whereby mutant TP53 impacts diverse cellular pathways by interacting with proteins that are not normally engaged by wt TP53 [1-6]. The GOF effects of mutant TP53 were reported to be essential for the sustained proliferation and survival of malignant cells and it was therefore proposed that agents that can remove mutant TP53 protein would have substantial therapeutic impact [7-9]. In this review article we discuss evidence for and against the value of targeting mutant TP53 protein for cancer therapy.

A non-dividing cell population with high pyruvate dehydrogenase kinase activity regulates metabolic heterogeneity and tumorigenesis in the intestine

Although reprogramming of cellular metabolism is a hallmark of cancer, little is known about how metabolic reprogramming contributes to early stages of transformation. Here, we show that the histone deacetylase SIRT6 regulates tumor initiation during intestinal cancer by controlling glucose metabolism. Loss of SIRT6 results in an increase in the number of intestinal stem cells (ISCs), which translates into enhanced tumor initiating potential in APCmin mice. By tracking down the connection between glucose metabolism and tumor initiation, we find a metabolic compartmentalization within the intestinal epithelium and adenomas, where a rare population of cells exhibit features of Warburg-like metabolism characterized by high pyruvate dehydrogenase kinase (PDK) activity. Our results show that these cells are quiescent cells expressing +4 ISCs and enteroendocrine markers. Active glycolysis in these cells suppresses ROS accumulation and enhances their stem cell and tumorigenic potential. Our studies reveal that aerobic glycolysis represents a heterogeneous feature of cancer, and indicate that this metabolic adaptation can occur in non-dividing cells, suggesting a role for the Warburg effect beyond biomass production in tumors.

Epstein–Barr virus latency programs dynamically sensitize B cells to ferroptosis

SignificanceEpstein-Barr virus (EBV) contributes to Burkitt lymphoma and post-transplant lymphoproliferative disease (PTLD). EBV-transforming programs activate lipid metabolism to convert B cells into immortalized lymphoblastoid cell lines (LCL), a PTLD model. We found that stages of EBV transformation generate lipid reactive oxygen species (ROS) byproducts to varying degrees, and that a Burkitt-like phase of B cell outgrowth requires lipid ROS detoxification by glutathione peroxidase 4 and its cofactor glutathione. Perturbation of this redox defense in early stages of transformation or in Burkitt cells triggered ferroptosis, a programmed cell death pathway. LCLs were less dependent on this defense, a distinction tied to EBV latency programs. This highlights ferroptosis induction as a potential therapeutic approach for prevention or treatment of certain EBV+ lymphomas.

Roles of pre-formed martensite in below-Ms bainite formation, microstructure, strain partitioning and impact absorption energies of low-carbon bainitic steel

The roles of pre-formed martensite (PM) in below-Ms bainite formation, microstructure, crystallography, strain partitioning and mechanical properties of a low-carbon bainitic steel were investigated using electron-backscattered diffraction, transmission electron microscopy, micro digital image correlation technique and mechanical tests. It is demonstrated that the pre-formation of martensite eliminates the incubation time for bainite transformation at various austempering temperatures below Ms, indicative of its acceleration effect at the early stage of transformation. This effect is mainly attributed to the surfaces or tips of the PM acting as the nuclei of subsequently-formed bainite, with initial bainite tending to form around the PM. However, the finishing time for below-Ms bainite transformation, especially at even lower temperatures, is retarded, owing to the dividing effect of PM on parent austenite grains, the decreasing effect of lowered isothermal temperature on the diffusion rate of carbon atoms and the strengthening effect of lowered isothermal temperature on supercooled austenite. PM and its adjacent bainitic laths have nearly the same crystallographic orientation and belong to the same block. The pre-formation of martensite largely refines the bainitic blocks/laths and retained austenite. The specimens with PM show relatively uniform strain partitioning among various phases, contrasting with the specimens without PM, for which strains are highly concentrated in the bainite region nearby fresh martensite/austenite (M/A) blocks or between adjacent M/A blocks. The impact absorption energies of the specimens with PM, when austempered at 30–60 °C below Ms, are more than twice higher than those of the specimens without PM, at no expense of tensile properties.

Digital Transformation of Transportation in the Age of COVID-19

Purpose: To highlight the key trends in the transportation industry and the role of emerging technologies and digital transformation in acceleration of value creation. The conceptual framework suggests how such transformation could be implemented. Design/methodology/approach: Research in a focus group was carried out where selected digital transformation frameworks were reviewed, and one was selected as the most applicable to the transportation industry. The selected framework was adopted for the transportation industry. Findings: 1. Value creation should be positioned as the key objective of transformation. 2. Digital transformation is not so much about technology as it is about people. 3. The staged approach towards transformation allows it to be paced with account being taken of the maturity of technology as well as the maturity of competencies across the organization. For a successful digital transformation, the organization invests in development of digital capabilities. Moving towards digital means a mindset shift, cultural change and adoption of new methods of working. Research limitations/implications: Transportation companies are at the early stage of transformation at such a scale. The case studies on successful transformations are limited. Therefore, experience is gathered mainly by the test and learn process. It is recommended that findings are validated with a wider group of experts when transformation matures. Comparing the same framework usage in other industries can also offer additional learnings to be considered by change leaders. Originality/value: Transportation industry is in a process of transformation towards connected, electric and autonomous solutions, accelerated during the COVID-19 pandemic. The presented framework, adopted for the transportation industry, offers a practical tool for executives and change leaders to lead the transformation.

MiR-486-3p was downregulated at microRNA profiling of adrenals of multiple endocrine neoplasia type 1 mice, and inhibited human adrenocortical carcinoma cell lines

Adrenocortical carcinoma is a rare aggressive disease commonly recurring regardless of radical surgery. Although data on genomic alterations in malignant tumors are accumulating, knowledge of molecular events of importance for initiation of adrenocortical transformation is scarce. In an attempt to recognize early molecular alterations, we used adrenals from young multiple endocrine neoplasia type 1 conventional knock-out mice (Men1+/−) closely mimicking the human MEN1 trait (i.e. transformation of pituitary, parathyroid, endocrine pancreatic, and adrenocortical cells). MicroRNA array and hierarchical clustering showed a distinct pattern. Twenty miRNAs were significantly upregulated and eleven were downregulated in Men1+/− compared to wild type littermates. The latter included the known suppressor miRNA miR-486-3p, which was chosen for transfection in human adrenocortical carcinoma cell lines H295R and SW13. Cell growth decreased in miR-486-3p overexpressing clones and levels of the predicted target gene fatty acid synthase (FASN) and its downstream product, palmitic acid, were lowered. In conclusion, heterozygous inactivation of Men1 in adrenals results in distinct miRNA profile regulating expression of genes with impact on tumorigenesis, e.g. transcription, nucleic acid and lipid metabolism. Low levels of miR-486-3p in the early stages of transformation may contribute to proliferation by increasing FASN and thus fatty acid production. FASN as a potentially druggable target for treatment of the devastating disease adrenocortical carcinoma warrants further studies.

Damage development during the strain induced phase transformation of austenitic stainless steels at low temperatures

The strain-induced martensitic transformation greatly affects the plastic behavior of the metastable austenitic stainless steels. The martensitic transformation continuously changes the initially homogeneous material into a strongly heterogeneous bi-phase one. In addition to the hardening behavior, this phenomenon would influence the damage growth and load-carrying capacity of the material during the plastic deformation. In this study, plastic behavior of the material AISI 304 including the hardening and damage growth, has been examined at low temperature; where a high rate of martensitic transformation affects the microstructure strongly. Experimental analysis and microscopic observations have been performed for evaluating the martensite content and damage growth. In addition, based on the continuum damage mechanics, a simplified damage evolution model has been proposed to capture the effect of phase transformation on the damage growth rate explicitly. The results show that the damage initiates with a considerable rate in early stages of transformation, however at higher levels of transformation, damage growth rate decreases until a sudden fracture. The presented model properly predicts the observed damage behavior.

An In Vivo Kras Allelic Series Reveals Distinct Phenotypes of Common Oncogenic Variants.

KRAS is the most frequently mutated oncogene in cancer, yet there is little understanding of how specific KRAS amino acid changes affect tumor initiation, progression, or therapy response. Using high-fidelity CRISPR-based engineering, we created an allelic series of new LSL-Kras mutant mice, reflecting codon 12 and 13 mutations that are highly prevalent in lung (KRASG12C), pancreas (KRASG12R), and colon (KRASG13D) cancers. Induction of each allele in either the murine colon or pancreas revealed striking quantitative and qualitative differences between KRAS mutants in driving the early stages of transformation. Furthermore, using pancreatic organoid models, we show that KRASG13D mutants are sensitive to EGFR inhibition, whereas KRASG12C-mutant organoids are selectively responsive to covalent G12C inhibitors only when EGFR is suppressed. Together, these new mouse strains provide an ideal platform for investigating KRAS biology in vivo and for developing preclinical precision oncology models of KRAS-mutant pancreas, colon, and lung cancers. SIGNIFICANCE: KRAS is the most frequently mutated oncogene. Here, we describe new preclinical models that mimic tissue-selective KRAS mutations and show that each mutation has distinct cellular consequences in vivo and carries differential sensitivity to targeted therapeutic agents.See related commentary by Kostyrko and Sweet-Cordero, p. 1626.This article is highlighted in the In This Issue feature, p. 1611.

The Evolution of the Kazakhstani Silk Road Section from a Transport into a Logistics Corridor and the Economic Sustainability of Regional Development in Central Asia

Central Asian countries attract investment in transport infrastructure to rebuild the Silk Road paths and enjoy economic benefits from the participation in international trade. The Kazakhstani government approached the Russian and Chinese governments intending to join the Western Europe–Western China (WE–WC) initiative to boost the country’s regional development. The paper aims to assess how the WE–WC transport corridor affected the economic potential of linking cities and regions starting from the quality of transport infrastructure and leading to their export potential. The study’s findings showed that the Kazakhstan section of the WE–WC corridor was at an early stage of transformation from a transport into an economic corridor. While the Russia-Uzbekistan section continues to serve mainly a transit function and operate at the level of transport infrastructure, the China-Kyrgyzstan section has started evolving from the level of multimode transport corridor to the level of logistics corridor. The economic sustainability of the WE–WC linking mining and agricultural regions of Kazakhstan still comes into question and depends on the government’s further region-specific policy actions.

Relationships between the Size of Aggregates, Particulate Organic Matter Content, and Decomposition of Plant Residues in Soil

The distribution of total organic matter (Corg), particulate organic matter (CPOM), and potentially mineralizable organic matter (C0) in mega- (10–5 and 5–2 mm), macro- (2–0.25 mm), and microaggregates (<0.25 mm) isolated by dry sieving from gray and agrogray soils (Luvic Retic Greyzemic Phaeozems) of different land uses was studied. In the soils under forest and meadow, the highest Corg content was detected in the megaaggregates of 5–2 mm in size (43 and 37% of Corg in whole soil sample, respectively), whereas in the arable soil, it was found in macroaggregates (45%). In the uncultivated soil, the CPOM was mainly accumulated in megaaggregates (65–72% of the CPOM in the whole sample); in the arable soil, it was equally distributed between mega- and macroaggregates (46–45%). The fine (0.25–0.05 mm) CPOM subfraction in the uncultivated and arable soils contained 1.3- and 2.3-fold more carbon, respectively, as compared with the coarse (2–0.25 mm) CPOM subfraction. The C0 content in the aggregates correlated with CPOM and Corg. Decomposition of plant residues with a wide C : N ratio in soil increased with a decrease in the aggregate size. However, aggregate size did not influence the decomposition of plant residues with a narrow C : N ratio. The effect of aggregate size on the decomposition rate mainly appeared at the early stages of transformation of plant residues.

APC-β-catenin-TCF signaling silences the intestinal guanylin-GUCY2C tumor suppressor axis

ABSTRACTSporadic colorectal cancer initiates with mutations in APC or its degradation target β-catenin, producing TCF-dependent nuclear transcription driving tumorigenesis. The intestinal epithelial receptor, GUCY2C, with its canonical paracrine hormone guanylin, regulates homeostatic signaling along the crypt-surface axis opposing tumorigenesis. Here, we reveal that expression of the guanylin hormone, but not the GUCY2C receptor, is lost at the earliest stages of transformation in APC-dependent tumors in humans and mice. Hormone loss, which silences GUCY2C signaling, reflects transcriptional repression mediated by mutant APC-β-catenin-TCF programs in the nucleus. These studies support a pathophysiological model of intestinal tumorigenesis in which mutant APC-β-catenin-TCF transcriptional regulation eliminates guanylin expression at tumor initiation, silencing GUCY2C signaling which, in turn, dysregulates intestinal homeostatic mechanisms contributing to tumor progression. They expand the mechanistic paradigm for colorectal cancer from a disease of irreversible mutations in APC and β-catenin to one of guanylin hormone loss whose replacement, and reconstitution of GUCY2C signaling, could prevent tumorigenesis

P16-T Early signs of transformation of neocortical activity to epileptiform patterns in experimental model of epilepsy

This study was aimed at receiving information concerning organization of the cortical cellular activity in relation to the epileptiform EEG patterns, using ionic model of experimental formation of epileptic focus. This investigation was supported by the KBN grant, Nr4-T11E-006-22. Evaluation of the relationship between EEG patterns and cellular activity was attempted in the region of parietal association cortex (middle suprasylvian gyrus) in the group of five adult cats. Multiunit cellular activity was recorded with sampling frequency 4 kHz, using permanently implanted multicontact concentric electrode: 16 contacts, each about 40 micrometers of diameter and the distance between contacts of 200 micrometers. The electrode was implanted in the vicinity of cannula enabling subdural transfer of artificial cerebrospinal fluid with increased concentration of potassium ions. The recording and perfusion was performed in quiet, awake animal without necessity of using any pharmacological treatment. Early signs of transformation of neocortical activity to epileptiform patterns show considerable degree of independence of the patterns of cellular activity with respect to EEG. The incident of increased intensity and generalization of cellular activity creates the development of variable, irregular superficial electric fields within wide frequency range. This early stage of transformation of cortical activity to epileptiform patterns ends with the appearance of definite patterns of cellular activity, predominantly in internal cortical cell layers with corresponding EEG slow waves and/or spikes. The results suggest the possibility of existence of transient “paroxysmal” cellular activities without coexistence of standard epileptiform patterns in EEG records.

Guanylate cyclase C (GUCY2C) as a preventative and therapeutic target in colorectal cancers (CRCs) arising through divergent genomic pathways.

595 Background: CRCs arise through distinct mutations, including in APC pathway leading to tubular adenomas (TAs); in BRAF, with epigenetic silencing of CDX2, leading to serrated adenomas (SAs); and in the DNA mismatch repair machinery driving microsatellite instability (MSI). The APC pathway involves loss of the hormone guanylin, silencing the tumor suppressing receptor GUCY2C. Indeed, oral hormone replacement is an emerging strategy to reactivate GUCY2C and prevent CRC. Moreover, retained expression by tumors arising from TAs has established GUCY2C as a therapeutic target to prevent and treat metastatic CRC. Here, we defined the potential role of the guanylin-GUCY2C axis, and its suitability as a target, in tumors arising through the SA and MSI pathways. Methods: We compared guanylin-GUCY2C protein and mRNA expression between human TAs (n = 18), SAs (n = 15), MSI tumors (n = 7) and their matched normal adjacent tissue. Genetic mouse models of serrated and MSI tumors were used to confirm findings and elucidate mechanisms. Results: Guanylin hormone was eliminated in TAs, SAs and MSI tumors compared to their normal adjacent tissues. In contrast to the hormone, the tumor suppressing receptor GUCY2C was retained in TAs and MSI tumors. Surprisingly, GUCY2C expression was nearly eliminated in SAs reflecting loss of the transcription factor CDX2. Changes in the guanylin-GUCY2C axis in human SAs and MSI tumors were precisely recapitulated in genetic mouse models. Conclusions: Guanylin is universally lost at the earliest stages of transformation in tumors arising through divergent genomic mechanisms suggesting its utility as a biomarker of CRC initiation. These data reveal the possibility of guanylin loss silencing GUCY2C in the pathophysiology of, and oral hormone replacement to restore GUCY2C signaling to prevent, MSI tumors. Also, they highlight the potential for targeting GUCY2C to prevent and treat metastases arising from TAs and MSI tumors. In contrast, loss of GUCY2C excludes patients with SAs as candidates for GUCY2C-based prevention and therapy.