Increased Cell Mobility Research Articles

N-acetylcysteine effects on extracellular polymeric substances of Xylella fastidiosa: A spatiotemporal investigation with implications for biofilm disruption

BackgroundThe matrix of extracellular polymeric substances (EPS) present in biofilms greatly amplifies the problem of bacterial infections, protecting bacteria against antimicrobial treatments and eventually leading to bacterial resistance. The need for alternative treatments that destroy the EPS matrix becomes evident. N-acetylcysteine (NAC) is one option that presents diverse effects against bacteria; however, the different mechanisms of action of NAC in biofilms have yet to be elucidated. ObjectivesIn this work, we performed microscopy studies at micro and nano scales to address the effects of NAC at single cell level and early-stage biofilms of the Xylella fastidiosa phytopathogen. MethodsWe show the physical effects of NAC on the adhesion surface and the different types of EPS, as well as the mechanical response of individual bacteria to NAC concentrations between 2 and 20 mg/mL. ResultsNAC modified the conditioning film on the substrate, broke down the soluble EPS, resulting in the release of adherent bacteria, decreased the volume of loosely bound EPS, and disrupted the biofilm matrix. Tightly bound EPS suffered structural alterations despite no solid evidence of its removal. In addition, bacterial force measurements upon NAC action performed with InP nanowire arrays showed an enhanced momentum transfer to the nanowires due to increased cell mobility resulting from EPS removal. ConclusionsOur results clearly show that conditioning film and soluble EPS play a key role in cell adhesion control and that NAC alters EPS structure, providing solid evidence that NAC actuates mainly on EPS removal, both at single cell and biofilm levels.

Diversity and function of mountain and polar supraglacial DNA viruses

Mountain and polar glaciers cover 10% of the Earth’s surface and are typically extreme environments that challenge life of all forms. Viruses are abundant and active in supraglacial ecosystems and play a crucial role in controlling the supraglacial microbial communities. However, our understanding of virus ecology on glacier surfaces and their potential impacts on downstream ecosystems remains limited. Here, we present the supraglacial virus genome (SgVG) catalog, a 15-fold expanded genomic inventory of 10,840 DNA-virus species from 38 mountain and polar glaciers, spanning habitats such as snow, ice, meltwater, and cryoconite. Supraglacial DNA-viruses were highly specific compared to viruses in other ecosystems yet exhibited low public health risks. Supraglacial viral communities were primarily constrained by habitat, with cryoconite displaying the highest viral activity levels. We observed a prevalence of lytic viruses in all habitats, especially in cryoconite, but a high level of lysogenic viruses in snow and ice. Additionally, we found that supraglacial viruses could be linked to ∼83% of obtained prokaryotic phyla/classes and possessed the genetic potential to promote metabolism and increase cold adaptation, cell mobility, and phenolic carbon use of hosts in hostile environmental conditions using diverse auxiliary metabolic genes. Our results provide the first systematic characterization of the diversity, function, and public health risks evaluation of mountain and polar supraglacial DNA viruses. This understanding of glacial viruses is crucial for function assessments and ecological modeling of glacier ecosystems, especially for the Tibetan Plateau’s Mountain glaciers, which support ∼20% of the human populations on Earth.

Interaction between membranous EBP50 and myosin 9 as a favorable prognostic factor in ovarian clear cell carcinoma.

Ezrin-binding phosphoprotein 50 (EBP50) is a scaffold protein that is required for epithelial polarity. Knockout (KO) of membranous EBP50 (Me-EBP50) in ovarian clear cell carcinoma (OCCC) cells induced an epithelial-mesenchymal transition (EMT)-like phenotype, along with decreased proliferation, accelerated migration capability, and induction of cancer stem cell (CSC)-like properties. Shotgun proteomics analysis of proteins that co-immunoprecipitated with EBP50 revealed that Me-EBP50 strongly interacts with myosin 9 (MYH9). Specific inhibition of MYH9 with blebbistatin phenocopied Me-EBP50 knockout, and blebbistatin treatment potentiated the effects of Me-EBP50 knockout. In OCCC cells from clinical samples, Me-EBP50 and MYH9 were co-localized at the apical plasma membrane. Patients with a combination of Me-EBP50-high and MYH9-high scores had the best prognosis for overall and progression-free survival. Our data suggest that Me-EBP50 has tumor-suppressive effects through the establishment and maintenance of epithelial polarization. In contrast, loss of Me-EBP50 expression induces EMT-like phenotypes, probably due to MYH9 dysfunction; this results in increased cell mobility and enhanced CSC-like properties, which in turn promote OCCC progression.

Transforming properties of MET receptor exon 14 skipping can be recapitulated by loss of the CBL ubiquitin ligase binding site.

MET is a receptor tyrosine kinase that is activated in many cancers through various mechanisms. MET exon 14 (Ex14) skipping occurs in 3% of nonsmall cell lung tumors. However, the contribution of the regulatory sites lost upon this skipping, which include a phosphorylated serine (S985) and a binding site for the E3 ubiquitin ligase CBL (Y1003), remains elusive. Sequencing of 2808 lung tumors revealed 71 mutations leading to MET exon 14 skipping and three mutations affecting Y1003 or S985. In addition, MET exon 14 skipping and MET Y1003F induced similar transcriptional programs, increased the activation of downstream signaling pathways, and increased cell mobility. Therefore, the MET Y1003F mutation is able to fully recapitulate responses induced by MET exon 14 skipping, suggesting that loss of the CBL binding site is the main contributor of cell transformation induced by MET Ex14 mutations.

Renal clear cancer cells regulate the differentiation of urine-derived stem cells to carcinoma-associated fibroblasts via RUNX3/TGF-β1 signaling axis.

Clear cell renal cell carcinoma (ccRCC), the most common pathological subtype of renal cancer, is one of the significant health concerns due to limited clinically effective treatments. Nevertheless, targeting carcinoma-associated fibroblasts in the tumor microenvironment has emerged as a promising innovative strategy for renal cancer therapy. Thus, this study is aimed to explore the role and molecular mechanism of urine-derived stem cells (USCs) in the progression and metastasis of ccRCC. Initially, wound-healing and transwell experiments were used to assess the migration and invasion abilities of the cells. Then, western blot analysis (WB) and quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses were used to demonstrate the relevant protein and messenger RNA expression levels. Finally, hematoxylin-eosin and immunohistochemical stainings were performed to evaluate metastasis and protein expression in lung tumors. The coculture of USCs with the ccRCC cell lines significantly enhanced their migratory and invasive abilities. WB and qRT-PCR analyses exhibited that ccRCC cell lines significantly increased cell mobility markers transcriptional and protein levels in USCs. Finally, the in vivo investigations in nude mice showed that USCs promoted the proliferation and migration of ccRCC-based xenograft tumors. In summary, these findings demonstrated that USCs promoted ccRCC tumorigenesis and development in vivo and in vitro by regulating the Runt-related transcription factor 3/transforming growth factor-β1 signaling axis.

Effect of p53 and its N-terminally truncated isoform, Δ40p53, on breast cancer migration and invasion.

Breast cancer is the most diagnosed malignancy in women, with over half a million women dying from this disease each year. In our previous studies, ∆40p53, an N‐terminally truncated p53 isoform, was found to be upregulated in breast cancers, and a high ∆40p53 : p53α ratio was linked with worse disease‐free survival. Although p53α inhibits cancer migration and invasion, little is known about the role of ∆40p53 in regulating these metastasis‐related processes and its role in contributing to worse prognosis. The aim of this study was to assess the role of ∆40p53 in breast cancer migration and invasion. A relationship between Δ40p53 and gene expression profiles was identified in oestrogen‐receptor‐positive breast cancer specimens. To further evaluate the role of Δ40p53 in oestrogen‐receptor‐positive breast cancer, MCF‐7 and ZR75‐1 cell lines were transduced to knockdown p53α or Δ40p53 and overexpress Δ40p53. Proliferation, migration and invasion were assessed in the transduced sublines, and gene expression was assessed through RNA‐sequencing and validated by reverse‐transcription quantitative PCR. Knockdown of both p53α and ∆40p53 resulted in increased proliferation, whereas overexpression of ∆40p53 reduced proliferation rates. p53α knockdown was also associated with increased cell mobility. ∆40p53 overexpression reduced both migratory and invasive properties of the transduced cells. Phenotypic findings are supported by gene expression data, including differential expression of LRG1, HYOU1, UBE2QL1, SERPINA5 and PCDH7. Taken together, these results suggest that, at the basal level, ∆40p53 works similarly to p53α in suppressing cellular mobility and proliferation, although the role of Δ40p53 may be cell context‐specific.

Axin1 translocates into the nucleus in hepatocyte growth factor induced epithelial-mesenchymal transition

Axin1 is a scaffold protein belonging to a destruction complex that degrades β-catenin. As an inhibitor of Wnt signaling, Axin1 is one of the most widely studied therapeutic targets in cancer treatment, particularly as targets for Tankyrase inhibitors. Axin1 has long been considered to be uninvolved in transforming growth factor beta induced epithelial-mesenchymal transition (EMT); the latter is known to transform cancer cells to a more aggressive phenotype that show increased cell mobility, drug-resistance and enhanced stem cell properties by remaining in the cytoplasm.In this study, the effects of overexpression of Axin1 on hepatocyte growth factor (HGF) induced EMT in HepG2 cells was investigated through analyses of in-cell western, morphological changes, cell growth curve, population doubling time and immunofluorescence staining.It was observed that Axin1 overexpression in HepG2 cells inhibited cellular growth. HGF treatment of Axin1 overexpressing cells resulted in the induction of EMT with the cells acquiring a fibroblast-like spindle morphology. This is the first report to describe that Axin1 translocated to the nucleus during HGF induced EMT, which is how this protein may exert EMT promoting functions. The result of this observation may rise the questions on the safety of Tankyrase inhibitors which stabilize Axin1 for cancer therapy.

Alpha-Synuclein-induced DNA Methylation and Gene Expression in Microglia

Synucleinopathy disorders are characterized by aggregates of α-synuclein (α-syn), which engage microglia to elicit a neuroinflammatory response. Here, we determined the gene expression and DNA methylation changes in microglia induced by aggregate α-syn. Transgenic murine Thy-1 promoter (mThy1)-Asyn mice overexpressing human α-syn are a model of synucleinopathy. Microglia from 3 and 13-month-old mice were used to isolate nucleic acids for methylated DNA and RNA-sequencing. α-Syn-regulated changes in gene expression and genomic methylation were determined and examined for functional enrichment followed by network analysis to further elucidate possible connections within the data. Microglial DNA isolated from our 3-month cohort had 5315 differentially methylated gene (DMG) changes, while RNA levels demonstrated a change in 119 differentially expressed genes (DEGs) between mThy1-Asyn mice and wild-type littermate controls. The 3-month DEGs and DMGs were highly associated with adhesion and migration signaling, suggesting a phenotypic transition from resting to active microglia. We observed 3742 DMGs and 3766 DEGs in 13-month mThy1-Asyn mice. These genes were often related to adhesion, migration, cell cycle, cellular metabolism, and immune response. Network analysis also showed increased cell mobility and inflammatory functions at 3 months, shifting to cell cycle, immune response, and metabolism changes at 13 months. We observed significant α-syn-induced methylation and gene expression changes in microglia. Our data suggest that α-syn overexpression initiates microglial activation leading to neuroinflammation and cellular metabolic stresses, which is associated with disease progression.

MiR-132 mediates cell permeability and migration by targeting occludin in high-glucose -induced ARPE-19 cells.

This study investigated the effects and mechanisms of miR-132 related to the permeability and mobility of human retinal pigment epithelium ARPE-19 cells in high-glucose (HG) condition. ARPE-19 cells were cultured in normal and HG condition and identified by immunofluorescence staining. Cell viability was assessed by the MTT assay, cell permeability was assessed by the FITC-dextran assay and cell mobility was assessed by the wound healing assay. Different miRNA and mRNA expression levels were determined by quantitative real-time polymerase chain reaction (RT-qPCR). The expression of tight junction-related proteins was determined by Western blot assay and immunofluorescence. The interaction between occludin and miR-132 was confirmed by a dual-luciferase reporter assay. We revealed that HG-treated ARPE-19 cells exhibited significantly increased miR-132 expression, decreased expression of the tight-junction markers including occludin and E-cadherin, and increased cell mobility and permeability. Occludin is a direct target of miR-132, which could regulate cell viability, mobility and permeability under HG condition through the JAK/STAT3 signaling pathway. These are the first data to suggest that miR-132 may contribute to the progression of diabetic retinopathy (DR) and that targeting the effect of miR-132 on occudin and the JAK/STAT3 pathway could represent a novel effective DR-treatment strategy.

Establishing multiple osteogenic differentiation pathways of mesenchymal stem cells through different scaffold configurations

Mimicking the complex organization of the extracellular matrix (ECM), especially its structure and dimensionality, is necessary to produce living tissues from stem cells. In compliance with a previously established role of nanofiber organization for the osteogenic differentiation of stem cells, here we used hybrid fibrinogen/poly(l-lactide-ε-caprolactone) (FBG/PLCL) nanofibers arranged in aligned and honeycomb configurations, to recapitulate the highly oriented ECM of the cortical bone and the sponge-like (i.e., honeycomb) environment of the cancellous one, respectively. Using special bilayered constructs, we demonstrate that the dimensionality (i.e., 2D vs. 3D) of the nanofibers as well as their architecture (i.e., honeycomb vs. aligned) affects differently the overall morphology and the expression of multiple osteogenic genes of human adipose-derived mesenchymal stem cells (ADMSCs). The cells had elongated shape with markedly increased cell mobility when seeded on aligned nanofibers. Conversely, on honeycomb-shaped nanofibers, ADMSCs initially concentrated inside the honeycomb curvatures adopting rounded morphology, but late, they formed network-like structures overlaying the honeycomb curvatures. By employing quantitative polymerase chain reaction (qPCR), we further show that a 3D environment generally supports the multiple osteogenic response of ADMSCs, but honeycomb and aligned architectures promote rather different differentiation pathways.

Prostate Cancer Epithelial Mesenchymal Transition by TGF-β1 exposure monitored with a Photonic Crystal Biosensor.

During prostate cancer progression, cancerous epithelial cells can undergo epithelial-mesenchymal transition (EMT). EMT is a crucial mechanism for the invasion and metastasis of epithelial tumors characterized by the loss of cell-cell adhesion and increased cell mobility. It is associated with biochemical changes such as epithelial cell markers E-cadherin and occludins being down-regulated, and mesenchymal markers vimentin and N-cadherin being upregulated. These changes in protein expression, specifically in the cell membrane, may be monitored via biophysical principles, such as changes in the refractive index (RI) of the cell membrane. In our previous research, we demonstrated the feasibility of using cellular RI as a unique contrast parameter to accomplish label-free detection of prostate cancer cells. In this paper, we report the use of our Photonic-Crystal biosensor in a Total-Internal-Reflection (PC-TIR) configuration to construct a label-free biosensing system, which allows for ultra-sensitive quantification of the changes in cellular RI due to EMT. We induced prostate cancer cells to undergo EMT by exposing these cells to soluble Transforming Growth Factor Beta 1 (TGF-β1). The biophysical characteristics of the cellular RI were quantified extensively in comparison to non-induced cancer cells. Our study shows promising clinical potential in utilizing the PC-TIR biosensing system not only to detect prostate cancer cells, but also to evaluate changes in prostate cancer cells due to EMT.

LncRNA LINP1 confers tamoxifen resistance and negatively regulated by ER signaling in breast cancer

Tamoxifen (TAM) is frequently used to treat patients with estrogen receptor-positive (ER+) breast cancer; however, the development of endocrine resistance represents a major impediment for successful treatment. Recent studies have demonstrated that long non-coding RNAs (lncRNAs) may serve critical roles in regulating endocrine resistance in breast cancer. In the present study, it was determined that the expression of lncRNA in nonhomologous end joining pathway 1 (LINP1) was increased in tamoxifen-resistant breast cancer cells, and that LINP1 knockdown significantly attenuated the tamoxifen resistance and viability of tamoxifen-resistant breast cancer cells in vitro and in vivo. LINP1 knockdown increased apoptosis in cells following treatment with tamoxifen. Furthermore, LINP1 overexpression resulted in increased cell mobility by regulating the EMT process. Mechanistically, LINP1 is a direct target of ER-mediated transcriptional repression, and both tamoxifen treatment and hormone deprivation increased the expression of LINP1. LINP1 overexpression was associated with downregulation of the levels of ER protein and attenuated the estrogen response, which is a pivotal contributing factor to anti-estrogen resistance. Taken together, the present study highlights the pivotal role of LINP1 in tamoxifen resistance, which may serve as a potential target to improve the effectiveness and efficacy of tamoxifen treatment in breast cancer.

Toward Decoding Bioelectric Events in Xenopus Embryogenesis: New Methodology for Tracking Interplay Between Calcium and Resting Potentials In Vivo

Although chemical signaling during embryogenesis is readily addressed by a plethora of available techniques, the developmental functions of ionic signaling are still poorly understood. It is increasingly realized that bioelectric events in nonneural cells are critical for pattern regulation, but their study has been hampered by difficulties in monitoring and manipulating them in vivo. Recent developments in visualizing electrical signaling dynamics in the field of neuroscience have facilitated functional experiments that reveal instructive developmental bioelectric signals. However, there is a pressing need for additional tools to explore time-dependent ionic signaling to understand complex endogenous dynamics. Here, we present methodological advances, including 4D imaging and data analysis, for improved tracking of calcium flux in the Xenopus laevis embryo, lowering the barrier for in vivo physiology work in this important model system. Using these techniques, we investigated the relationship between bioelectric ion channel activity and calcium, finding that cell hyperpolarization and depolarization both induce persistent static elevation of cytoplasmic calcium levels that fade over developmental time. These calcium changes correlate with increased cell mobility in early embryos and abnormal craniofacial morphology in later embryos. We thus highlight membrane potential modulation as a tractable tool for modulation of signaling cascades that rely on calcium as a transduction mechanism. The methods we describe facilitate the study of important novel aspects of developmental physiology, are extendable to numerous classes of existing and forthcoming fluorescent physiological reporters, and establish highly accessible, inexpensive protocols for their investigation.

Abstract 1782: ANKRD52 inhibited tumor metastasis through dephosphorylation of PAK1 in lung adenocarcinomas

Abstract PAK1 is an important oncogene involved in the progression of a variety of cancer types including lung cancer. Although PAK1 inhibition is shown to suppress tumor progression, specific PAK1 inhibitors are not available due to the complex structure and insufficient understanding of this protein. In an attempt to find TAZ (WW domain-containing transcription regulator 1) regulated tumor suppressor, a member of ankyrin repeat proteins, ankyrin repeat domain 52 (ANKRD52), is observed to suppress PAK1 phosphorylation. Ankyrin repeat proteins are known to function as a platform for protein-protein interactions, and ANKRD52 was shown to interact with protein phosphatase 6 (PP6). Immunohistochemistry staining in lung cancer tissue revealed prolonged disease-free survival in high ANKRD52 expressing cases. Using lung cancer cell lines, ANKRD52 knockdowns showed significantly increased cell mobility while forced expressed ANKRD52 decreased cell mobility. Using mass spectrometry analysis, p21-activated kinases (PAK1) was identified to interact with ANKRD52. Upregulated PAK1 phosphorylation was detected in the knockdowns of ANKRD52 or PP6. Our model demonstrated a novel anti-metastatic protein, ANKRD52, that regulates cell mobility through interactions with PP6 and dephosphorylation of PAK1. Citation Format: Ting-Fang Lee, Yin-Pu Liu, Yen-Fan Lin, Chong-Fang Hsu, Cheng-Wen Wu. ANKRD52 inhibited tumor metastasis through dephosphorylation of PAK1 in lung adenocarcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1782.

Abstract 5508: ANKRD52 inhibited tumor metastasis in lung adenocarcinoma

Abstract Cancer metastasis is an ultimate challenge in our effort to fight cancer as a life-threatening disease. A member of ankyrin repeat proteins, ankyrin repeat domain 52 (ANKRD52), is studied here to be involved in the regulation of lung adenocarcinoma metastasis. Ankyrin repeat proteins are known to function as a platform for protein-protein interactions, and ANKRD52 was shown to interact with protein phosphatase 6 (PP6). Immunohistochemistry staining in lung adenocarcinomas tissues revealed low ANKRD52 expressing in stage-IV patients compared to those in stages I to III. Overexpressed ANKRD52 prevented lung cancer formation in the xenograft model. Using lung cancer cell lines, ANKRD52 knockdowns showed significantly increased cell mobility while forced expression decreased cell mobility. Using mass spectrometry analysis, p21-activated kinases (PAK1) was identified to interact with ANKRD52. The regulation of PAK1 phosphorylation by the ANKRD52-PP6 complex is essential to cell mobility. Our model demonstrated a novel anti-metastatic protein, ANKRD52, that regulates cell mobility through interacting with PP6 leading to PAK1 dephosphorylation. Citation Format: Ting-Fang Lee, Yen-Fan Lin, Ying-Pu Liu, Cheng-Wen Wu. ANKRD52 inhibited tumor metastasis in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5508.

Mining of potential microRNAs with clinical correlation - regulation of syndecan-1 expression by miR-122-5p altered mobility of breast cancer cells and possible correlation with liver injury.

MicroRNAs are small noncoding RNAs acting as novel biomarkers of various diseases and potential regulators of protein expression and functions. Syndecan-1 is the heparan sulfate proteoglycan associated with malignancy of various cancers, including breast cancer. In this study, we proposed a experimental workflow to investigate potential microRNAs that regulate SDC1 expression and affect breast cancer cell mobility.MicroRNA candidates were selected from available Gene Expression Omnibus datasets on breast malignancy. Further in silico duplex hybridization and multiplex PCR approach were used to screen potential microRNAs. Analysis showed increased syndecan-1 expression but decreased miR-122-5p level upon breast malignancy. Western blot and in vitro luciferase assay confirmed the targeting of 3′-untranslated region of syndecan-1 and suppression of syndecan-1 expression by miR-122-5p. The suppression of syndecan-1 expression by miR-122-5p or shRNAs against syndecan-1 increased breast cancer cell mobility; while overexpression of syndecan-1 inhibited cell mobility. In further, miR-122-5p was enriched in liver cell-derived exosomes that was able to suppress syndecan-1 expression and increase cell mobility in breast cancer cells.In conclusion, our results suggested the downregulation of SDC1 by miR-122-5p or liver-cell-derived exosomes would enhance breast cancer cell mobility. Metastasis or mobility of breast cancer cells might be affected by circulating miR-122-5p and not directly correlated with progression of breast cancer.

The Prognostic Role of Immunohistochemistry in Primary Bone Tumors

Abstract In the last decades, immunohistochemistry (IHC) has shown an important role in tumor differential diagnosis and has proven its prognostic role. Due to the various histological subtypes of primary malignant bone tumors, its role will be more important in the future. Based on recent studies, tumor growth, cell mobility, and metastases strongly correlate to the survival of these patients. An increased number of specific IHC markers have been used to determine the aggressiveness of the metastatic capacity of these tumors in enhancing early specific oncological therapies. This study presents 15 cases of primary malignant bone tumors, over a period of 4 years (2014-2018), from the Orthopedics and Traumatology Department of the University Emergency Hospital in Bucharest, where we evaluated the proliferation index using Ki67 IHC marker, tissue remodelation, the presence of necrosis in osteosarcoma cases in which chemotherapy was applied, and the aspect of the cytoskeleton with vimentin. Besides the histological aspect, we evaluated the tumor site, invasion and extension to the surrounding tissues (Computer Tomography, Magnetic Resonance) and vascularization with angiography, all these properties having an important prognostic role. Our findings were similar to other research papers in literature; showing that a fast growing and high proliferation index with increased cell mobility has a worse prognosis. Pulmonary metastases occurred in a relative short time in high-grade osteosarcomas, despite the chemotherapy, and multiple metastases were present at 6 months in a dedifferentiated chondrosarcoma case, in which the high-grade sarcoma was an osteosarcoma. Based on the literature, we also think that some specific markers might have multiple roles regarding the tumor growth local invasion and metastasis.

New biological research and understanding of Papanicolaou's test.

The development of the Papanicolaou smear test by Dr. George Nicholas Papanicolaou (1883-1962) is one of the most significant achievements in screening for disease and cancer prevention in history. The Papanicolaou smear has been used for screening of cervical cancer since the 1950s. The test is technically straightforward and practical and based on a simple scientific observation: malignant cells have an aberrant nuclear morphology that can be distinguished from benign cells. Here, we review the scientific understanding that has been achieved and continues to be made on the causes and consequences of abnormal nuclear morphology, the basis of Dr. Papanicolaou's invention. The deformed nuclear shape is caused by the loss of lamina and nuclear envelope structural proteins. The consequences of a nuclear envelope defect include chromosomal numerical instability, altered chromatin organization and gene expression, and increased cell mobility because of a malleable nuclear envelope. HPV (Human Papilloma Virus) infection is recognized as the key etiology in the development of cervical cancer. Persistent HPV infection causes disruption of the nuclear lamina, which presents as a change in nuclear morphology detectable by a Papanicolaou smear. Thus, the causes and consequences of nuclear deformation are now linked to the mechanisms of viral carcinogenesis, and are still undergoing active investigation to reveal the details. Recently a statue was installed in front of the Papanicolaou's Cancer Research Building to honor the inventor. Remarkably, the invention nearly 60 years ago by Dr. Papanicolaou still exerts clinical impacts and inspires scientific inquiries.

Label-free in vitro prostate cancer cell detection via photonic-crystal biosensor.

Prostate-specific antigen (PSA) biomarker assays are the current clinical method for mass screening of prostate cancer. However, high false-positive rates are often reported due to PSA's low specificity, leading to an urgent need for the development of a more specific detection system independent of PSA levels. In our previous research, we demonstrated the feasibility of using cellular refractive indices (RI) as a unique contrast parameter to accomplish label-free detection of prostate cancer cells via variance testing, but were unable to determine if a specific cell was cancerous or noncancerous. In this paper, we report the use of our Photonic-Crystal biosensor in a Total-Internal-Reflection (PC-TIR) configuration to construct a label-free imaging system, which allows for the detection of individual prostate cancer cells utilizing cellular RI as the only contrast parameter. Noncancerous prostate (BPH-1) cells and prostate cancer (PC-3) cells were mixed at varied ratios and measured concurrently. Additionally, we isolated and induced PC-3 cells to undergo epithelial-mesenchymal transition (EMT) by exposing these cells to soluble factors such as TGF-01. The biophysical characteristics of the cellular RI were quantified extensively in comparison to non-induced PC-3 cells as well as BPH-1 cells. EMT is a crucial mechanism for the invasion and metastasis of epithelial tumors characterized by the loss of cell-cell adhesion and increased cell mobility. Our study shows promising clinical potential in utilizing the PC-TIR biosensor imaging system to not only detect prostate cancer cells, but also evaluate prostate cancer progression.

Abstract 4843: ANKRD52 inhibited tumor metastasis through dephosphorylation of PAK1 in lung adenocarcinoma

Abstract As a leading cause of cancer-related deaths, metastasis is the ultimate challenge in our effort to fight cancer as a life-threatening disease. A member of ankyrin repeat proteins, ankyrin repeat domain 52 (ANKRD52), is studied here to be involved in the regulation of lung adenocarcinoma metastasis. Ankyrin repeat proteins are known to function as a platform for protein-protein interactions, and ANKRD52 was shown to interact with protein phosphatase 6 (PP6). This study aimed to investigate the anti-metastatic roles of ANKRD52 in lung adenocarcinoma. Immunohistochemistry staining in lung cancer tissue revealed prolonged disease-free survival in high ANKRD52 expressing cases. Using lung cancer cell lines, ANKRD52 knockdowns showed significantly increased cell mobility while forced expressed ANKRD52 decreased cell mobility. Using mass spectrometry analysis, p21-activated kinases (PAK1) was identified to interact with ANKRD52. Upregulated PAK1 phosphorylation was detected in ANKRD52 or PP6 knockdowns. Our model demonstrated a novel anti-metastatic protein, ANKRD52, that regulates cell mobility through interactions with PP6 and dephosphorylation of PAK1. Citation Format: Yen-Fan Lin, Ying-Pu Liu, Ting-Fang Lee, Cheng-Wen Wu. ANKRD52 inhibited tumor metastasis through dephosphorylation of PAK1 in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4843. doi:10.1158/1538-7445.AM2017-4843