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Background: We previously reported in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) treated with immune checkpoint inhibitors (ICIs), pretreatment higher lactate dehydrogenase (LDH) and absolute (abx) neutrophils as well as lower percent (%) lymphocytes correlated with worse overall survival (OS). In this study we aimed to develop a prognostic signature for HNSCC treated with ICIs using these peripheral blood biomarkers (PBBMs)., Methods: Adults with R/M HNSCC treated with ICIs at our institution from 08/2012 to 03/2021 with pretreatment PBBMs were included. Follow-up continued until 02/15/2022. The cohort (n = 151) was randomly split into training (n = 100) and testing (n = 51) datasets. A prognostic score incorporating LDH, % lymphocytes, and abx neutrophils was developed from the training dataset using Cox proportional hazards regression. In the training dataset, a grid search identified the optimal cutpoints classifying patients into high, medium, and low-risk groups (trichotomized signature) as well as high vs. low-risk groups (dichotomized signature). The prognostic score, dichotomized and trichotomized signatures were then validated in the testing dataset., Results: Training and testing datasets showed no clinically meaningful differences in clinicodemographic characteristics or PBBMs. An OS prognostic model was developed from the training dataset: Risk score = 1.24*log10(LDH) - 1.95*log10(% lymphocytes) + 0.47*log10(abx neutrophils). Optimal risk score cutpoints for the dichotomized and trichotomized signatures were defined in the training dataset, and Kaplan-Meier curves for both dichotomized and trichotomized signatures showed good separation between risk groups. Risk scores were calculated in the testing dataset, where the trichotomized signature demonstrated overlap between low and medium-risk groups but good separation from the high-risk group while the dichotomized signature showed clear separation between low and high-risk groups. Higher risk score correlated with worse OS (HR 2.08, [95%CI 1.17-3.68], p = 0.012). Progression-free survival Kaplan-Meier curves likewise showed excellent separation between dichotomized risk groups in the training and testing datasets., Conclusions: We developed a prognostic signature for OS based on 3 previously identified PBBMs for HNSCC treated with ICIs and identified a high-risk group of patients least likely to have survival benefit from ICIs. This signature may improve ICI patient selection and warrants validation in an independent cohort as well as correlation with CPS., Competing Interests: Declarations Ethics approval and consent to participate This study was reviewed and approved by the Fred Hutchinson Cancer Research Institutional Review Board (IRB ID: STUDY00007717). The requirement to obtain informed consent was waived. Consent for publication Not applicable. Competing interests Conflict of Interest Disclosures: Dr. Futran reported educational consultancy role for Stryker Corporation. Dr. Rodriguez reported receipt of institutional research funding from AstraZeneca, Ayala, Bristol Myers Squibb, Ignyta, and Merck, and reported advisory board membership for Cue Biopharma. The other authors declare no potential conflicts of interest., (© 2024. The Author(s).)

Objective: Age-related vocal atrophy (ARVA) negatively impacts voice and quality of life (QOL). This study aims to determine utility-based QOL in ARVA patients, correlate findings with traditional patient-reported outcome measures (PROMs), and generate utility-based inferences., Methods: Forty ARVA patients were prospectively recruited from a tertiary care center. Health utility was measured using standard gamble, time trade-off, and visual analog scale, assessing participants' current health states relative to defined comparison states (blindness/death). Traditional PROMs (Voice Handicap Index-10 [VHI-10] and Voice-Related Quality of Life Scale [V-RQOL]) were also collected. Descriptive and paired statistics were performed to determine health utility, and Pearson correlation assessed the association between PROMs and health utilities., Results: Mean health utility in ARVA was 0.84 ± 0.22, 0.88 ± 0.17, and 0.62 ± 0.25 using standard gamble, time trade-off, and visual analog scale, respectively. There were positive correlations between V-RQOL and time trade-off (r = 0.66; p < 0.0001) as well as with standard gamble (r = 0.47; p = 0.002). Participants with ARVA reported no difference in health utility impact between their voice impairment and monocular blindness (Mean dif 10.9; 95% CI -1.6, 23.5; p = 0.101). Patients with ARVA were willing to part with an average 4.6 ± 6.1 years of life to restore normal voice., Conclusions: ARVA patients view their voice impairment as a significant health decrement, comparable to monocular blindness. These findings underscore the substantial impact of ARVA on QOL and highlight the need for continued research and new therapies., Level of Evidence: 4 Laryngoscope, 2024., (© 2024 The American Laryngological, Rhinological and Otological Society, Inc.)

Crack detection is a long-standing topic in structural health monitoring. Conventional damage detection techniques rely on intensive, time-consuming, resource-intensive intervention. The current trend of crack detection emphasizes using deep neural networks to build an automated pipeline from measured signals to damaged areas. This work focuses on the seismic-wave-based technique of crack detection for plate structures. Previous work proposed an encoder-decoder network to extract crack-related wave patterns from measured wave signals and predict crack existence on the plate. We extend previous work with extensive experiments on different network components and a data preprocessing strategy. The proposed methods are tested on an expanded crack detection dataset. We found that a robust backbone network, such as Densely Connected Convolutional Network (DenseNet) can effectively extract the features characterizing cracks of wave signals, and by using the reference wave field for normalization, the accuracy of detecting small cracks can be further improved., (© 2024. The Author(s).)

Objective: To identify characteristics associated with successful electrolarynx (EL) use after total laryngectomy (TL)., Methods: Records of 196 adults who underwent TL from 03/15/2012 to 03/15/2022 at the University of Washington and Puget Sound Veterans Affairs were reviewed. Characteristics included age, Charlson Comorbidity Index, social support, pre-operative radiation (RT) and chemoradiation (CRT), and 6-month post-TL swallow status. EL success was evaluated using pre-defined criteria of intelligibility, reliability, and independence with use. Poisson regressions and robust standard error estimates were used to estimate unadjusted risk ratios for each characteristic. Statistically significant characteristics were included in multivariate analysis (MVA) to estimate adjusted risk ratios., Results: Median age was 64, median Charlson Comorbidity Index was 5, 170 (87%) were male, 159 (81%) had high social support, and 159 (81%) attained post-TL full-oral diet. Pre-operatively, 110 (56%) had RT, including 55 (28%) with CRT. Ninety-three (47%) met our criteria for EL success. Characteristics significantly associated with EL success included social support ( p  = .037) and post-TL full-oral diet ( p  = .037); both approached significance on MVA. EL success varied by pre-operative treatment on univariate ( p  = .005) and MVA ( p  = .014). Compared to no prior RT or CRT, the probability of EL success was 29% higher with prior RT and 29% lower with prior CRT in MVA, although these associations did not reach significance., Conclusions: In this retrospective review, EL success correlated with high social support, post-TL full-oral diet, and pre-operative treatment history. These results warrant validation in a larger prospective study to help guide the choice of voice rehabilitation modalities or intensified speech therapy., Level of Evidence: 4., Competing Interests: The authors declare no potential conflicts of interest., (© 2024 The Authors. Laryngoscope Investigative Otolaryngology published by Wiley Periodicals LLC on behalf of The Triological Society.)

Background: Perineural invasion (PNI) in head and neck squamous cell carcinoma (HNSCC) portends poor prognosis. Extent of treatment of nerve pathways with varying degrees of PNI and patterns of failure following elective neural radiotherapy (RT) remain unclear., Methods: Retrospective review of HNSCC patients with high-risk (clinical/gross, large-nerve, extensive) or low-risk (microscopic/focal) PNI who underwent curative-intent treatment from 2010 to 2021., Results: Forty-four patients (mean follow-up 22 months; 59% high-risk, 41% low-risk PNI) were included. Recurrence following definitive treatment occurred in 31% high-risk and 17% low-risk PNI patients. Among high-risk patients, 69% underwent surgery with post-operative RT and 46% underwent elective neural RT. Local control (83% low-risk vs. 75% high-risk), disease-free, and overall survival did not differ between groups., Conclusions: High local control rates were achieved in high-risk PNI patients treated with adjuvant or primary RT, including treatment of both involved and uninvolved, communicating cranial nerves, with few failures in electively treated regions., (© 2023 Wiley Periodicals LLC.)

Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Little is known regarding associations between peripheral blood biomarkers (PBBMs) and survival, response, and toxicity in recurrent/metastatic head and neck squamous cell carcinomas (R/M HNSCC) treated with immune checkpoint inhibitors (ICIs)., Methods: In this single-institution retrospective cohort study, a dataset of patients with R/M HNSCC treated with ICIs between 08/2012-03/2021 was established, including demographic and clinicopathologic characteristics. Pretreatment PBBMs were collected and evaluated for associations with grade ≥3 adverse events (G ≥ 3AE) by CTCAEv5, objective response (ORR) by RECIST 1.1, overall survival (OS), and progression-free survival (PFS). Multivariable models for each outcome were created using elastic net variable selection., Results: Our study included 186 patients, with 51 (27%) demonstrating complete or partial response to immunotherapy. Multivariable models adjusted for ECOG performance status (PS), p16, and smoking demonstrated that pretreatment higher LDH and absolute neutrophils, as well as lower percent lymphocytes correlated with worse OS and PFS. Higher LDH and lower % lymphocytes also correlated with worse ORR., Conclusions: In the largest study to date examining PBBMs in ICI-treated R/M HNSCCs, our variable selection method revealed PBBMs prognostic for survival and response to immunotherapy. These biomarkers warrant further investigation in a prospective study along with validation with CPS biomarker., (© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

The development of a new dynamic lattice element method (dynamicLEM) as well as its application in the simulation of the propagation of body waves in discontinuous and heterogeneous media is the focus of this research paper. The conventional static lattice models are efficient numerical methods to simulate crack initiation and propagation in cemented geomaterials. The advantages of the LEM and the developed dynamic solution, such as simulation of arbitrary crack initiation and propagation, illustration and simulation of existing inherent material heterogeneity as well as stress redistribution upon crack opening, opens a new engineering field and tool for material analysis. To realize the time dependency of the dynamic LEM, the equation of motion of forced vibration is solved while using the Newmark-[Formula: see text] method and implementing the non-linear Newton-Raphson Jacobian method. The method validation is done according to the results of a boundary element method (BEM) in the plane P-SV-wave propagation within a plane strain domain. Further tests comparing the generated wave types, simulation and study of crack discontinuities as well as inherent heterogeneities in the geomaterials are conducted to illustrate the accurate applicability of the new dynamic lattice method. The results indicate that with increasing heterogeneity within the material, the wave field becomes significantly scattered and further analysis of wave fields according to the wavelength/heterogeneity ratio become indispensable. Therefore, in a heterogeneous medium, the application of continuum methods in relation to structural health monitoring should be precisely investigated and improved. The developed dynamic lattice element method is an ideal simulation tool to consider particle scale irregularities, crack distributions and inherent material heterogeneities and can be easily implemented in various engineering applications., (© 2022. The Author(s).)

Critical-sized defects of irregular bones requiring bone grafting, such as in craniofacial reconstruction, are particularly challenging to repair. With bone-grafting procedures growing in number annually, there is a reciprocal growing interest in bone graft substitutes to meet the demand. Autogenous osteo(myo)cutaneous grafts harvested from a secondary surgical site are the gold standard for reconstruction but are associated with donor-site morbidity and are in limited supply. We developed a bone graft strategy for irregular bone-involved reconstruction that is customizable to defect geometry and patient anatomy, is free of synthetic materials, is cellularized, and has an outer pre-vascularized tissue layer to enhance engraftment and promote osteogenesis. The graft, comprised of bioprinted human-derived demineralized bone matrix blended with native matrix proteins containing human mesenchymal stromal cells and encased in a simple tissue shell containing isolated, human adipose microvessels, ossifies when implanted in rats. Ossification follows robust vascularization within and around the graft, including the formation of a vascular leash, and develops mechanical strength. These results demonstrate an early feasibility animal study of a biofabrication strategy to manufacture a 3D printed patient-matched, osteoconductive, tissue-banked, bone graft without synthetic materials for use in craniofacial reconstruction. The bone fabrication workflow is designed to be performed within the hospital near the Point of Care., Competing Interests: Authors SM, TG, MC, MG, and JH were employed by the company Advanced Solutions Life Sciences. Author PG was employed by the company Cytiva. JH and MG are equity holders in Advanced Solutions Life Sciences. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Moss, Ortiz-Hernandez, Levin, Richburg, Gerton, Cook, Houlton, Rizvi, Goodwin, Golway, Ripley and Hoying.)

The identification of structural damages takes a more and more important role within the modern economy, where often the monitoring of an infrastructure is the last approach to keep it under public use. Conventional monitoring methods require specialized engineers and are mainly time-consuming. This research paper considers the ability of neural networks to recognize the initial or alteration of structural properties based on the training processes. The presented model, a spatially asymmetric encoder-decoder network, is based on 1D-Convolutional Neural Networks (CNN) for wave field pattern recognition, or more specifically the wave field change recognition. The proposed model is used to identify the change within propagating wave fields after a crack initiation within the structure. The paper describes the implemented method and the required training procedure to get a successful crack detection accuracy, where the training data are based on the dynamic lattice model. Although the training of the model is still time-consuming, the proposed new method has an enormous potential to become a new crack detection or structural health monitoring approach within the conventional monitoring methods., (© 2021. The Author(s).)

Objectives: The primary objective was to determine the rate of occult cervical nodal metastasis in patients undergoing elective neck dissection (END) during salvage laryngectomy. The secondary objective was to compare survival and postoperative complication rates between patients undergoing END versus observation., Methods: A medical librarian performed a comprehensive search for END outcomes in laryngeal cancer patients undergoing salvage laryngectomy after primary chemoradiation therapy. Seventeen retrospective studies and 1 prospective study met inclusion criteria, with a total of 1,141 patients (799 END, 350 observed)., Results: The rate of nodal positivity was 11% among patients who underwent END during their salvage laryngectomy. Three studies and 155 patients were included in a 5-year overall survival (OS) analysis with no significant difference in OS (95% confidence interval [CI]: 0.82-2.22). After inclusion of six studies and 494 patients (249 END, 245 observed), the risk of fistula formation was not statistically different (95% CI: 0.61-2.56). Due to significant heterogeneity between studies and inadequate data, most patients could not be included in the meta-analysis of outcomes., Conclusion: Salvage laryngectomy patients undergoing END have an occult nodal positivity rate of 11%. Meta-analysis showed no statistically significant differences in 5-year OS between patients undergoing END versus observation. Laryngoscope, 130:899-906, 2020., (© 2019 The American Laryngological, Rhinological and Otological Society, Inc.)

Background: Transsphenoidal pituitary surgery has evolved into a safe procedure with shorter hospitalizations, yet unplanned readmissions remain a quality measure for which there is a paucity of data. We sought to examine rates, timing, etiologic factors, and costs surrounding readmission after transsphenoidal pituitary surgery., Methods: The Nationwide Readmissions Database (NRD) was queried for patients who underwent transsphenoidal pituitary between January 2013 and November 2013. Patient, procedure, admission, and hospital-level characteristics were compared for patients with and without unplanned 30-day readmission. Multivariate logistic regression was used to identify readmission predictors. A total of 8546 patients were included in this retrospective study., Results: A total of 8546 patients with a median age of 54 years and female predominance were identified, with 742 patients experiencing at least 1 unplanned readmission within 30 days of index admission. Hypertension, hypothyroidism, diabetes, and obesity were common comorbidities among readmitted patients. Readmission was most frequently because of nervous system complications, followed by neurohypophyseal or electrolyte disorders, cerebrospinal fluid leak, hemorrhage, and meningitis. Median length and cost of stay of index admission was greater in the readmission group (p < 0.001). Fluid and electrolyte disorders as well as neurologic disease (most commonly epilepsy or convulsions) present on initial admission were predictive of length of initial stay and readmission (p < 0.001). Median readmission cost was $7723 and was expected to occur within 7 days., Conclusion: Approximately 8.7% of patients undergoing transsphenoidal pituitary surgery experience an unplanned readmission within 30 days of discharge. Risk factors identified should be considered to reduce preventable readmissions and identify medically complex patients., (© 2018 ARS-AAOA, LLC.)

Objectives/hypothesis: Squamous cell carcinoma of the retromolar trigone (RMT SCC) is a relatively uncommon primary site for oral cavity malignancy. However, given its proximity to the mandible and buccal mucosa, RMT SCC typically exhibits early invasion and generally presents at an advanced stage. Large-sample studies are needed to assess the epidemiology and clinical outcomes of this tumor. Our aim was to describe the determinants of survival in patients with RMT SCC., Study Design: Retrospective cohort study., Methods: Retrospective, population-based cohort study of patients in the Surveillance, Epidemiology, and End Results tumor registry who were diagnosed with RMT SCC from 1973 to 2012. Primary endpoints were overall survival (OS) and disease-specific survival (DSS)., Results: A total of 4,022 cases of RMT SCC were identified. The mean age at diagnosis was 65 years. Thirty-nine percent of cases presented with stage IV disease. The median OS by stages I to IV were 73.7, 52.4, 27.5, and 23.4 months, respectively (P < .05). Overall, 34.3% of patients underwent surgery, 23.5% received radiation therapy, and 34.1% had both surgical and radiation therapy. On multivariate analysis, advanced age, greater tumor size, and advanced stage were associated with worse OS and DSS (P < .05), surgery predicted improved OS and DSS (P < .05), and radiation therapy predicted improved OS only (P < .05)., Conclusions: RMT SCC is an aggressive malignancy that portends a poor prognosis, though early-stage tumors (stages I and II) have significantly improved survival. Any surgical intervention independently predicted higher survival outcomes. There may be a role of dual modality approaches, particularly for larger tumors., Level of Evidence: 4 Laryngoscope, 128:2740-2744, 2018., (© 2018 The American Laryngological, Rhinological and Otological Society, Inc.)

A cable model that includes polarization-induced capacitive current is derived for modeling the solitonic conduction of electrotonic potentials in neuronal branchlets with microstructure containing endoplasmic membranes. A solution of the nonlinear cable equation modified for fissured intracellular medium with a source term representing charge 'soakage' is used to show how intracellular capacitive effects of bound electrical charges within mitochondrial membranes can influence electrotonic signals expressed as solitary waves. The elastic collision resulting from a head-on collision of two solitary waves results in localized and non-dispersing electrical solitons created by the nonlinearity of the source term. It has been shown that solitons in neurons with mitochondrial membrane and quasi-electrostatic interactions of charges held by the microstructure (i.e., charge 'soakage') have a slower velocity of propagation compared with solitons in neurons with microstructure, but without endoplasmic membranes. When the equilibrium potential is a small deviation from rest, the nonohmic conductance acts as a leaky channel and the solitons are small compared when the equilibrium potential is large and the outer mitochondrial membrane acts as an amplifier, boosting the amplitude of the endogenously generated solitons. These findings demonstrate a functional role of quasi-electrostatic interactions of bound electrical charges held by microstructure for sustaining solitons with robust self-regulation in their amplitude through changes in the mitochondrial membrane equilibrium potential. The implication of our results indicate that a phenomenological description of ionic current can be successfully modeled with displacement current in Maxwell's equations as a conduction process involving quasi-electrostatic interactions without the inclusion of diffusive current. This is the first study in which solitonic conduction of electrotonic potentials are generated by polarization-induced capacitive current in microstructure and nonohmic mitochondrial membrane current.

Using steady-state electrical properties of non-ohmic dendrite based on cable theory, we derive electrotonic potentials that do not change over time and are localized in space. We hypothesize that clusters of such stationary, local and permanent pulses are the electrical signatures of enduring memories which are imprinted through nonsynaptic plasticity, encoded through epigenetic mechanisms, and decoded through electrotonic processing. We further hypothesize how retrieval of an engram is made possible by integration of these permanently imprinted standing pulses in a neural circuit through neurotransmission in the extracellular space as part of conscious recall that acts as a guiding template in the reconsolidation of long-term memories through novelty characterized by uncertainty that arises when new fragments of memories reinstate an engram by way of nonsynaptic plasticity that permits its destabilization. Collectively, these findings seem to reinforce this hypothesis that electrotonic processing in non-ohmic dendrites yield insights into permanent electrical signatures that could reflect upon enduring memories as fragments of long-term memory engrams.

Tumor cell metastasis is a complex process that has been mechanistically linked to the epithelial-mesenchymal transition (EMT). The double-negative feedback loop between the microRNA-200 family and the Zeb1 transcriptional repressor is a master EMT regulator, but there is incomplete understanding of how miR-200 suppresses invasion. Our recent efforts have focused on the tumor cell-matrix interactions essential to tumor cell activation. Herein we utilized both our Kras/p53 mutant mouse model and human lung cancer cell lines to demonstrate that upon miR-200 loss integrin β1-collagen I interactions drive 3D in vitro migration/invasion and in vivo metastases. Zeb1-dependent EMT enhances tumor cell responsiveness to the ECM composition and activates FAK/Src pathway signaling by de-repression of the direct miR-200 target, CRKL. We demonstrate that CRKL serves as an adaptor molecule to facilitate focal adhesion formation, mediates outside-in signaling through Itgβ1 to drive cell invasion, and inside-out signaling that maintains tumor cell-matrix contacts required for cell invasion. Importantly, CRKL levels in pan-cancer TCGA analyses were predictive of survival and CRKL knockdown suppressed experimental metastases in vivo without affecting primary tumor growth. Our findings highlight the critical ECM-tumor cell interactions regulated by miR-200/Zeb1-dependent EMT that activate intracellular signaling pathways responsible for tumor cell invasion and metastasis.

Better understanding of the biophysical and biochemical cues of the tumor extracellular matrix environment that influence metastasis may have important implications for new cancer therapeutics. Initial exploration into this question has used naturally derived protein matrices that suffer from variability, poor control over matrix biochemistry, and inability to modify the matrix biochemistry and mechanics. Here, we report the use of a synthetic polymer-based scaffold composed primarily of poly(ethylene glycol), or PEG, modified with bioactive peptides to study murine models of lung adenocarcinoma. In this study, we focus on matrix-derived influences on epithelial morphogenesis of a metastatic cell line (344SQ) that harbors mutations in Kras and p53 (trp53) and is prone to a microRNA-200 (miR-200)-dependent epithelial-mesenchymal transition (EMT) and metastasis. The modified PEG hydrogels feature biospecific cell adhesion and cell-mediated proteolytic degradation with independently adjustable matrix stiffness. 344SQ encapsulated in bioactive peptide-modified, matrix metalloproteinase-degradable PEG hydrogels formed lumenized epithelial spheres comparable to that seen with three-dimensional culture in Matrigel. Altering both matrix stiffness and the concentration of cell-adhesive ligand significantly influenced epithelial morphogenesis as manifest by differences in the extent of lumenization, in patterns of intrasphere apoptosis and proliferation, and in expression of epithelial polarity markers. Regardless of matrix composition, exposure to TGF-β induced a loss of epithelial morphologic features, shift in expression of EMT marker genes, and decrease in mir-200 levels consistent with EMT. Our findings help illuminate matrix-derived cues that influence epithelial morphogenesis and highlight the potential utility that this synthetic matrix-mimetic tool has for cancer biology., (©2012 AACR.)

Metastatic cancer is extremely difficult to treat, and the presence of metastases greatly reduces a cancer patient's likelihood of long-term survival. The ZEB1 transcriptional repressor promotes metastasis through downregulation of microRNAs (miRs) that are strong inducers of epithelial differentiation and inhibitors of stem cell factors. Given that each miR can target multiple genes with diverse functions, we posited that the prometastatic network controlled by ZEB1 extends beyond these processes. We tested this hypothesis using a mouse model of human lung adenocarcinoma metastasis driven by ZEB1, human lung carcinoma cells, and human breast carcinoma cells. Transcriptional profiling studies revealed that ZEB1 controls the expression of numerous oncogenic and tumor-suppressive miRs, including miR-34a. Ectopic expression of miR-34a decreased tumor cell invasion and metastasis, inhibited the formation of promigratory cytoskeletal structures, suppressed activation of the RHO GTPase family, and regulated a gene expression signature enriched in cytoskeletal functions and predictive of outcome in human lung adenocarcinomas. We identified several miR-34a target genes, including Arhgap1, which encodes a RHO GTPase activating protein that was required for tumor cell invasion. These findings demonstrate that ZEB1 drives prometastatic actin cytoskeletal remodeling by downregulating miR-34a expression and provide a compelling rationale to develop miR-34a as a therapeutic agent in lung cancer patients.

Changes in expression and localization of proteins that regulate cell and tissue polarity are frequently observed in carcinoma. However, the mechanisms by which changes in cell polarity proteins regulate carcinoma progression are not well understood. Here, we report that loss of polarity protein expression in epithelial cells primes them for cooperation with oncogenes or changes in tissue microenvironment to promote invasive behavior. Activation of ErbB2 in cells lacking the polarity regulators Scribble, Dlg1 or AF-6, induced invasive properties. This cooperation required the ability of ErbB2 to regulate the Par6/aPKC polarity complex. Inhibition of the ErbB2-Par6 pathway was sufficient to block ErbB2-induced invasion suggesting that two polarity hits may be needed for ErbB2 to promote invasion. Interestingly, in the absence of ErbB2 activation, either a combined loss of two polarity proteins, or exposure of cells lacking one polarity protein to cytokines IL-6 or TNFα induced invasive behavior in epithelial cells. We observed the invasive behavior only when cells were plated on a stiff matrix (Matrigel/Collagen-1) and not when plated on a soft matrix (Matrigel alone). Cells lacking two polarity proteins upregulated expression of EGFR and activated Akt. Inhibition of Akt activity blocked the invasive behavior identifying a mechanism by which loss of polarity promotes invasion of epithelial cells. Thus, we demonstrate that loss of polarity proteins confers phenotypic plasticity to epithelial cells such that they display normal behavior under normal culture conditions but display aggressive behavior in response to activation of oncogenes or exposure to cytokines.

The microRNA-200 (miR-200) family restricts epithelial-mesenchymal transition (EMT) and metastasis in tumor cell lines derived from mice that develop metastatic lung adenocarcinoma. To determine the mechanisms responsible for EMT and metastasis regulated by this microRNA, we conducted a global liquid chromatography/tandem mass spectrometry analysis to compare metastatic and nonmetastatic murine lung adenocarcinoma cells which had undergone EMT because of loss of miR-200. An analysis of syngeneic tumors generated by these cells identified multiple novel proteins linked to metastasis. In particular, the analysis of conditioned media, cell surface proteins, and whole-cell lysates from metastatic and nonmetastatic cells revealed large-scale modifications in the tumor microenvironment. Specific increases were documented in extracellular matrix (ECM) proteins, peptidases, and changes in distribution of cell adhesion proteins in the metastatic cell lines. Integrating proteomic data from three subproteomes, we defined constituents of a multilayer protein network that both regulated and mediated the effects of TGFβ. Lastly, we identified ECM proteins and peptidases that were directly regulated by miR-200. Taken together, our results reveal how expression of miR-200 alters the tumor microenvironment to inhibit the processes of EMT and metastasis.

Metastatic disease is a primary cause of cancer-related death, and factors governing tumor cell metastasis have not been fully elucidated. Here, we address this question by using tumor cell lines derived from mice that develop metastatic lung adenocarcinoma owing to expression of mutant K-ras and p53. Despite having widespread somatic genetic alterations, the metastasis-prone tumor cells retained a marked plasticity. They transited reversibly between epithelial and mesenchymal states, forming highly polarized epithelial spheres in three-dimensional culture that underwent epithelial-to-mesenchymal transition (EMT) following treatment with transforming growth factor-beta or injection into syngeneic mice. This transition was entirely dependent on the microRNA (miR)-200 family, which decreased during EMT. Forced expression of miR-200 abrogated the capacity of these tumor cells to undergo EMT, invade, and metastasize, and conferred transcriptional features of metastasis-incompetent tumor cells. We conclude that tumor cell metastasis is regulated by miR-200 expression, which changes in response to contextual extracellular cues.

Purpose: To investigate a family afflicted with X-linked retinoschisis and to determine the pedigree leading to such an occurrence., Design: Observational case series., Methods: Visual acuities were measured at The Aga Khan University Hospital Ophthalmology clinic. Slit-lamp examination, direct and indirect ophthalmoscopies were performed on each of the seven members of this family. The pedigree was established by appropriate questioning about the rest of their family., Results: The pedigree revealed the homozygosity of the four daughters for the XLRS mutations borne out of the consanguineous marriage between an affected father and a carrier mother., Conclusions: This is the first report showing that consanguineous marriages lead to homozygous pairing of XLRS genes in female children, as concluded after a MEDLINE search.