Keratin 17 is a prognostic and predictive biomarker in pancreatic ductal adenocarcinoma

OBJECTIVES

To determine the role of keratin 17 (K17) as a predictive biomarker for response to chemotherapy by defining thresholds of K17 expression based on immunohistochemical tests that could be used to optimize therapeutic intervention for patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

We profiled K17 expression, a hallmark of the basal molecular subtype of PDAC, by immunohistochemistry in 2 cohorts of formalin-fixed, paraffin-embedded PDACs (n = 305). We determined a K17 threshold of expression to optimize prognostic stratification according to the lowest Akaike information criterion and explored the potential relationship between K17 and chemoresistance by multivariate predictive analyses.

RESULTS

Patients with advanced-stage, low K17 PDACs treated using 5-fluorouracil (5-FU)-based chemotherapeutic regimens had 3-fold longer survival than corresponding cases treated with gemcitabine-based chemotherapy. By contrast, PDACs with high K17 did not respond to either regimen. The predictive value of K17 was independent of tumor mutation status and other clinicopathologic variables.

CONCLUSIONS

The detection of K17 in 10% or greater of PDAC cells identified patients with shortest survival. Among patients with low K17 PDACs, 5-FU-based treatment was more likely than gemcitabine-based therapies to extend survival.

Keratin 17 modulates the immune topography of pancreatic cancer

Background

The immune microenvironment impacts tumor growth, invasion, metastasis, and patient survival and may provide opportunities for therapeutic intervention in pancreatic ductal adenocarcinoma (PDAC). Although never studied as a potential modulator of the immune response in most cancers, Keratin 17 (K17), a biomarker of the most aggressive (basal) molecular subtype of PDAC, is intimately involved in the histogenesis of the immune response in psoriasis, basal cell carcinoma, and cervical squamous cell carcinoma. Thus, we hypothesized that K17 expression could also impact the immune cell response in PDAC, and that uncovering this relationship could provide insight to guide the development of immunotherapeutic opportunities to extend patient survival.

Methods

Multiplex immunohistochemistry (mIHC) and automated image analysis based on novel computational imaging technology were used to decipher the abundance and spatial distribution of T cells, macrophages, and tumor cells, relative to K17 expression in 235 PDACs.

Results

K17 expression had profound effects on the exclusion of intratumoral CD8 + T cells and was also associated with decreased numbers of peritumoral CD8 + T cells, CD16 + macrophages, and CD163 + macrophages (p < 0.0001). The differences in the intratumor and peritumoral CD8 + T cell abundance were not impacted by neoadjuvant therapy, tumor stage, grade, lymph node status, histologic subtype, nor KRAS, p53, SMAD4, or CDKN2A mutations.

Conclusions

Thus, K17 expression correlates with major differences in the immune microenvironment that are independent of any tested clinicopathologic or tumor intrinsic variables, suggesting that targeting K17-mediated immune effects on the immune system could restore the innate immunologic response to PDAC and might provide novel opportunities to restore immunotherapeutic approaches for this most deadly form of cancer.

Abstract A042: Keratin 17 is a negative prognostic and predictive biomarker in pancreatic ductal adenocarcinoma

Background: There is an urgent need to understand why patients with clinically and histologically identical pancreatic ductal adenocarcinomas (PDACs) differ in response to treatment, disease progression, and survival. Although two standard chemotherapies are available, predictive biomarkers to guide regimen selection have not been defined. We previously reported that keratin 17 (K17) expression is a hallmark of PDAC cases with shortest patient survival. Furthermore, K17, explored using in vitro and in vivo murine models, drives resistance to gemcitabine and 5-fluorouracil, the most common chemotherapeutic agents in the two chemotherapies. Here, we aimed to validate the prognostic value of K17 and to further explore its role as a predictive biomarker. Methods: We used a cohort of 305 cases, with localized disease and who had gone tumor resection. An indirect immunoperoxidase method was used to detect K17 expression on surgical specimens, as previously described. Survival was plotted using the Kaplan–Meier method and hazard ratios (HRs) were calculated using Cox proportional hazard regressions for both, overall survival (OS) and progression-free survival (PFS). Results: Patients in the high-K17 expression group had shorter overall survival [median=25 mo., HR=1.511, p=0.0338] than those in the low-K17 expression group (median=42 mo.). In addition, high K17 expression was associated with shorter median OS (p=0.0280) and PFS (p=0.0434) in patients who were treated with gemcitabine (GEM) or with Gemcitabine/nab-Paclitaxel (GEMTAX) therapy (OS p=0.1959, PFS p=0.0724), compared to low-K17 counterparts. When we further separated our cohort by K17 level of expression and compared GEM and GEMTAX responses, we found that patients with tumors with high K17 expression do not benefit from GEMTAX adjuvant therapy (p=0.0356). Of note, K17 expression within the responder group was significantly lower than in tumors within the non-responder group for both Gem and GEMTAX (p&lt;0.001). Conclusions: K17 expression is confirmed as a robust prognostic biomarker, significantly correlated with poor OS and PFS in two independent cohorts of PDAC patients. More importantly, our results indicate that K17 expression predicts PDAC resistance to gemcitabine and poor response to GEMTAX. Collectively, our findings have implications could guide the development of K17 as a predictive biomarker for gemcitabine-based interventions in both adjuvant and palliative settings, to optimize therapeutic efficacy for PDAC.

Citation Format: Lyanne Oblein, Lucia Roa-Peña, Sruthi Babu, Felicia D. Allard, Natalia D. Marchenko, Luisa F. Escobar-Hoyos, Kenneth R. Shroyer. Keratin 17 is a negative prognostic and predictive biomarker in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A042.

Abstract C071: Keratin 17 excludes CD8-positive T cells and recruits CD163-positive macrophages in pancreatic ductal adenocarcinoma

Background: Keratin 17 (K17) is a negative prognostic biomarker, overexpressed in the biologically most aggressive forms of pancreatic ductal adenocarcinoma (PDAC). In other anatomic sites and disease processes, K17 expression also correlates with immune cell infiltrates and could block T-cell infiltration. Thus, we hypothesized that K17 expression correlates with the inflammatory microenvironment in PDAC. In this study, we aimed to determine the relationship between the stromal immune cell infiltrates and K17 expression, using multiplexed immunohistochemistry (mIHC) and our suite of deep learning tools to quantitatively evaluate the expression of four biomarkers of T-cells and macrophages in PDAC. Methods: mIHC was performed on representative sections of 201 primary PDACs from Stony Brook University Hospital, Thomas Jefferson University Hospital, Cedars Sinai Medical Center, and from a national cohort (KYT, Pancreatic Cancer Action Network, and Perthera). Antibodies for CD4 (helper T-cells), CD8 (cytotoxic T-cells), CD16 (pan-macrophage), CD163 (M2 macrophages), pancytokeratin, and K17 were provided by Roche Diagnostics Corporation through a sponsored research agreement. mIHC was performed on a Discovery Ultra Autostainer (Roche), using horseradish peroxidase (HRP) and alkaline phosphatase (AP)-based protocols with multiple chromogens (Red: CD4, Purple: CD8, Yellow: CD16, Green: CD163, Teal: pancytokeratin, and Brown: K17) to enable multispectral imaging of diverse immune cell populations within the cancer microenvironment. A deep learning analysis workflow was used to detect and classify stromal inflammatory cells, in whole slide images (WSIs), generated using an Olympus VS120 digital microscope (Olympus, Tokyo, Japan). Pixel-wise predictions from a color auto-encoder (ColorAE) union UNET anchor UNET model were combined to create multi-class masks that were further analyzed to perform detection and classification. Results: The analysis of the inflammatory microenvironment focused on defining immune cell infiltrates located within 25 microns of the closest K17-positive versus K17-negative tumor cell in each representative section. Across the sum of K17-positive and negative zones/section, CD4 cell counts ranged from 0-10,617 (mean 2,709), CD8 cell counts ranged from 63-28,596 (mean 6,745), CD16 cell counts ranged from 4-7,797 (mean 3,024), and CD163 cell counts ranged from 35-34,696 (mean 14,968). CD4 T-helper cells, CD8 cytotoxic T cells, and CD16 macrophages were more numerous (respectively, p=0.0012; p=&lt;0.0001; p=&lt;0.0001) in K17-negative tumor zones compared to K17-positive zones. By contrast, the number of CD163 (M2) tumor-promoting macrophages was greater in K17 positive zones (p=0.0019). Conclusion: K17 expression by tumor cells impacts the chronic inflammatory microenvironment, shielding tumor cells from immune cell mediated cytotoxic responses, while recruiting tumor-promoting M2 macrophages, indicating that K17 impacts the immune response as a fundamental hallmark of aggression in PDAC.

Citation Format: Lyanne Oblein, Michael Horowitz, Mahmudul Hasan, Sruthi Babu, Mariana Torrente-Goncalves, Lucia Roa, Jaymie Oentoro, Jason Harper, Xin Yao Zheng, Wei Jiang, Andrew Hendifar, Natalie Moshayedi, Brent Larson, Veronica Placencio-Hickok, Edik Blais, Emmanuel Petricoin, Joel Saltz, Natalia D. Marchenko, Luisa F. Escobar-Hoyos, Kenneth Shroyer. Keratin 17 excludes CD8-positive T cells and recruits CD163-positive macrophages in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr C071.

Backyard poultry farming with improved germplasm: Sustainable food production and nutritional security in fragile ecosystem

Approximately 3 billion people were unable to afford a healthy diet in 2019 because of poverty and inequality. Most of these people live in Asia and Africa. Furthermore, 30% of the world population was affected by moderate to severe food insecurity in 2020, and most of this population lives in low- and middle-income countries. The world is at a critical juncture, and there is an urgent need for transformative food systems that ensure the empowerment of poor and vulnerable population groups, often smallholders with limited access to resources or those living in remote locations, as well as the empowerment of women, children, and youth (FAO, 2018). The backyard poultry production system (BPPS), as practiced by 80% of the world's rural population, can be that transformative change in low- and middle-income countries. Although the BPPS has low productivity, it still plays an important role in the food and nutritional security of rural people living in fragile ecosystems. Backyard poultry has been recognized as a tool for poverty alleviation and women empowerment besides ensuring food and nutritional security for rural poor. Poultry meat and eggs are the cheapest and best source of good quality protein, minerals, and vitamins. The introduction of improved backyard poultry germplasm has improved the productivity of this system in resource-poor settings and thereby improved the income and nutritional security of poor households. With these birds, the availability, access, utilization, and stability of food security have improved at household and national levels. Diseases, predation, non-availability of improved germplasm, lack of access to markets, and lack of skills are the major constraints to the adoption of improved backyard poultry. These constraints can be addressed by involving a network of community animal service providers. The improved backyard poultry germplasm will dominate the backyard poultry production system in the future and will be a tool for ensuring food and nutritional security on a sustainable basis, more particularly in low- and middle-income countries.

ECM-transmitted shear stress induces apoptotic cell extrusion in early breast gland development

Epithelial cells of human breast glands are exposed to various mechanical ECM stresses that regulate tissue development and homeostasis. Mechanoadaptation of breast gland tissue to ECM-transmitted shear stress remained poorly investigated due to the lack of valid experimental approaches. Therefore, we created a magnetic shear strain device that enabled, for the first time, to analyze the instant shear strain response of human breast gland cells. MCF10A-derived breast acini with basement membranes (BM) of defined maturation state and basoapical polarization were used to resemble breast gland morphogenesis in vitro. The novel biophysical tool was used to apply cyclic shear strain with defined amplitudes (≤15%, 0.2 Hz) over 22 h on living spheroids embedded in an ultrasoft matrix (&lt;60 Pa). We demonstrated that breast spheroids gain resistance to shear strain, which increased with BM maturation and basoapical polarization. Most intriguingly, poorly developed spheroids were prone to cyclic strain-induced extrusion of apoptotic cells from the spheroid body. In contrast, matured spheroids were insensitive to this mechanoresponse—indicating changing mechanosensing or mechanotransduction mechanisms during breast tissue morphogenesis. Together, we introduced a versatile tool to study cyclic shear stress responses of 3D cell culture models. It can be used to strain, in principle, all kinds of cell clusters, even those that grow only in ultrasoft hydrogels. We believe that this approach opens new doors to gain new insights into dynamic shear strain-induced mechanobiological regulation circuits between cells and their ECM.

Responses of birds and mammals to long-established wind farms in India

Wind turbines have been recognised as an alternative and clean-energy source with a low environmental impact. The selection of sites for wind-farm often creates serious conservation concerns on biodiversity. Wind turbines have become a serious threat to migratory birds as they collide with the turbine blades in some regions across the globe, while the impact on terrestrial mammals is relatively less explored. In this context, we assessed the responses of birds and mammals to the wind turbines in central Karnataka, India from January 2016 to May 2018 using carcass searches to quantify animal collisions (i.e., birds and bats), fixed radius point count for bird population parameters, and an occupancy framework for assessing the factor that determines the spatial occurrence of terrestrial mammals. The mean annual animal fatality rate per wind turbine was 0.26/year. Species richness, abundance, and unique species of birds were relatively higher in control sites over wind turbine sites. Species and functional compositions of birds in control sites were different from wind turbine sites, explaining the varied patterns of bird assemblages of different feeding guilds. Blackbuck, Chinkara, Golden Jackal, and Jungle Cat were less likely to occupy sites with a high number of wind turbines. The study indicates that certain bird and mammal species avoided wind turbine-dominated sites, affecting their distribution pattern. This is of concern to the management of the forested areas with wind turbines. We raised conservation issues and mitigating measures to overcome the negative effects of wind turbines on animals.

Dry heat sterilization as a method to recycle N95 respirator masks: The importance of fit

In times of crisis, including the current COVID-19 pandemic, the supply chain of filtering facepiece respirators, such as N95 respirators, are disrupted. To combat shortages of N95 respirators, many institutions were forced to decontaminate and reuse respirators. While several reports have evaluated the impact on filtration as a measurement of preservation of respirator function after decontamination, the equally important fact of maintaining proper fit to the users' face has been understudied. In the current study, we demonstrate the complete inactivation of SARS-CoV-2 and preservation of fit test performance of N95 respirators following treatment with dry heat. We apply scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) measurements, Raman spectroscopy, and contact angle measurements to analyze filter material changes as a consequence of different decontamination treatments. We further compared the integrity of the respirator after autoclaving versus dry heat treatment via quantitative fit testing and found that autoclaving, but not dry heat, causes the fit of the respirator onto the users face to fail, thereby rendering the decontaminated respirator unusable. Our findings highlight the importance to account for both efficacy of disinfection and mask fit when reprocessing respirators to for clinical redeployment.

Pan-Asian adaptation of the EHNS-ESMO-ESTRO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with squamous cell carcinoma of the head and neck

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of squamous cell carcinoma (SCC) of the oral cavity, larynx, oropharynx and hypopharynx was published in 2020. It was therefore decided by both the ESMO and the Korean Society of Medical Oncology (KSMO) to convene a special, virtual guidelines meeting in July 2021 to adapt the ESMO 2020 guidelines to consider the potential ethnic differences associated with the treatment of SCCs of the head and neck (SCCHN) in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with SCCHN (excluding nasopharyngeal carcinomas) representing the oncological societies of Korea (KSMO), China (CSCO), India (ISMPO), Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter was discussed when appropriate. This manuscript provides a series of expert recommendations (Clinical Practice Guidelines) which can be used to provide guidance to health care providers and clinicians for the optimisation of the diagnosis, treatment and management of patients with SCC of the oral cavity, larynx, oropharynx and hypopharynx across Asia.

Keratin 17 testing in pancreatic cancer needle aspiration biopsies predicts survival

BACKGROUND

Although pancreatic ductal adenocarcinoma (PDAC) has one of the lowest 5-year survival rates of all cancers, differences in survival exist between patients with clinically identical characteristics. The authors previously demonstrated that keratin 17 (K17) expression in PDAC, measured by RNA sequencing or immunohistochemistry (IHC), is an independent negative prognostic biomarker. Only 20% of cases are candidates for surgical resection, but most patients are diagnosed by needle aspiration biopsy (NAB). The aims of this study were to determine whether there was a correlation in K17 scores detected in matched NABs and surgical resection tissue sections and whether K17 IHC in NAB cell block specimens could be used as a negative prognostic biomarker in PDAC.

METHODS

K17 IHC was performed for a cohort of 70 patients who had matched NAB cell block and surgical resection samples to analyze the correlation of K17 expression levels. K17 IHC was also performed in cell blocks from discovery and validation cohorts. Kaplan-Meier and Cox proportional hazards regression models were analyzed to determine survival differences in cases with different levels of K17 IHC expression.

RESULTS

K17 IHC expression correlated in matched NABs and resection tissues. NAB samples were classified as high for K17 when ≥80% of tumor cells showed strong (2+) staining. High-K17 cases, including stage-matched cases, had shorter survival.

CONCLUSIONS

K17 has been identified as a robust and independent prognostic biomarker that stratifies clinical outcomes for cases that are diagnosed by NAB. Testing for K17 also has the potential to inform clinical decisions for optimization of chemotherapeutic interventions.

Keratin 17 Is a Novel Cytologic Biomarker for Urothelial Carcinoma Diagnosis

OBJECTIVES

The microscopic features of urine cytology specimens are subjective and may not reliably distinguish between benign urothelial cells and low-grade urothelial carcinoma (UC). Prior studies demonstrated that keratin 17 (K17) detection in biopsies is highly sensitive for UC. The current study aimed to define K17 diagnostic test performance for initial screening and detect recurrent UC in urine specimens.

METHODS

K17 was detected by immunocytochemistry (ICC) in consecutively collected urine specimens (2018-2019). A qualitative score for the K17 test was determined in 81 samples (discovery cohort) and validated in 98 samples (validation cohort). K17 sensitivity and specificity were analyzed in both cohorts across all grades of UC.

RESULTS

Based on the discovery cohort, the presence of 5 or more K17 immunoreactive urothelial cells (area under the curve = 0.90; P < .001) was the optimal threshold to define a K17-positive test. The sensitivity of the K17 ICC test for biopsy-confirmed UC was 35 of 36 (97%) and 18 of 21 (86%) in the discovery and validation cohorts, respectively. K17 was positive in 16 of 19 (84%) specimens with biopsy-confirmed low-grade UC and in 34 of 34 (100%) of specimens with high-grade UC.

CONCLUSIONS

K17 ICC is a highly sensitive diagnostic test for initial screening and detection of recurrence across all grades of UC.

Evaluation of Antibiotic Sensitivity Test against Ophthalmic Pathogens

Ophthalmic infections can cause damage to the structure of the eye which can lead to vision loss and blindness if left untreated. Ophthalmic infection or eye infections are caused by exposure to bacterial, fungal viral and protozoan are common with frequently reported in Asian countries. In the present study, the external ocular infected samples collected from Thanjavur Medical College Hospital, Thanjavur. Seven strains were isolated from the external ocular infected samples and identified a standard manual of Determinative Bacteriology by Bergy’s manual 12th edition. The commercial antibiotics and eye drops tested against Bacillus cereus, B. subtilis, Escherichia coli, Klebsiella sp. Pseudomonas sp. Streptococcus sp. and Staphylococcus aureus. The majority of the isolates were sensitive to tobramycin followed by moxifloxacin, gatifloxacin and ofloxacin. The resistant antibiotics are ciprofloxin and sensitive antibiotic was ampicillin was recorded with respective bacteria.

Spin-up conversion, exchange-interactions, and tailored magnetic properties in core-shell La2NiMnO6of small crystallites

La₂NiMnO₆-a ferromagnetic (FM) insulator offers tunable charge carriers and spins useful to devise its multiple properties and applications. In this view, we studied a core-shell La₂NiMnO₆(2-3 nm shell on 65 - 80 nm core) of a Ni²⁺/Ni³⁺(d⁷) to Mn⁴⁺/Mn³⁺(d⁴) spin-up conversion- revived a new FM phase-2, raising a spin-densityσ_s = 0.7 s a^-1over the Ni^2+/Mn⁴⁺species (phase-1),σ_s = 0.5 s a^-1, i.e. 2.12μ_B/f.u. larger spin moment. HRTEM images studied with x-ray diffraction characterizing core-shell structure that plays a crucial role in tuning the high spin FM phase-2 of profound properties. Below 110 K, the dc magnetization and ac magnetic susceptibilityχ(ω,T) reveal a metastable magnetic behavior on an antiferromagnetic canting of a spin-glass nature. The results follow a Vogel-Fulcher type relaxation with a relaxation timeτ₀∼ 10^-13s, confirming a spin-glass freezing behavior. Uniquely, FM field of phase-1 controls magnetics of phase 2 of a coupled magnet, modulating joint features with small thermal magnetic hysteresis on heating-cooling cycles.

Guideline for the management of hip fractures 2020: Guideline by the Association of Anaesthetists

We convened a multidisciplinary Working Party on behalf of the Association of Anaesthetists to update the 2011 guidance on the peri-operative management of people with hip fracture. Importantly, these guidelines describe the core aims and principles of peri-operative management, recommending greater standardisation of anaesthetic practice as a component of multidisciplinary care. Although much of the 2011 guidance remains applicable to contemporary practice, new evidence and consensus inform the additional recommendations made in this document. Specific changes to the 2011 guidance relate to analgesia, medicolegal practice, risk assessment, bone cement implantation syndrome and regional review networks. Areas of controversy remain, and we discuss these in further detail, relating to the mode of anaesthesia, surgical delay, blood management and transfusion thresholds, echocardiography, anticoagulant and antiplatelet management and postoperative discharge destination. Finally, these guidelines provide links to supplemental online material that can be used at readers' institutions, key references and UK national guidance about the peri-operative care of people with hip and periprosthetic fractures during the COVID-19 pandemic.

Abstract PO-040: Therapeutic targeting of keratin 17 functional domains and nuclear export uncover therapeutic vulnerabilities of pancreatic cancer

The purpose of this study is to launch a novel biomarker-based targeted therapy that may result in improved precision and efficacy for the treatment of pancreatic ductal adenocarcinoma (PDAC). We discovered that Keratin 17 (K17), an oncofetal intermediate filament and nuclear oncoprotein expressed in 50% of PDAC cases, is a biomarker of the most aggressive and treatment-resistant form of PDAC. We set out to validate K17 as a druggable target and to identify K17-targeting mechanisms. In pre-clinical mouse models, animals bearing K17+ PDACs display the shortest survival, suggesting that K17 drives tumor aggression and should be explored as a potential therapeutic target. We used the following two approaches aimed to inhibit K17 nuclear shuttle functions, in order to identify therapeutic strategies: 1) Targeting K17 functional domains: By protein-sequence modeling analyses and site-directed mutagenesis, we identified functional domains in K17 (K17-FDs) that bind to, shift the subcellular localization of, and promote the degradation of nuclear tumor suppressors (e.g. p27). Using SILAC mass spectrometry of nuclear proteomes from isogenic human cells, we found that 80% of the nuclear proteome is altered by K17, that half of these proteins encode the domain targeted by the K17-FDs, and that a large proportion of these proteins are involved in gene expression. Animals harboring tumors with mutated K17-FDs lived two-times longer than control animals bearing K17+ PDACs, suggesting that the K17-FDs may be therapeutic targets. We are currently testing small molecule and peptide inhibitors to target the K17-FDs in vitro and in vivo, as a discovery approach to design small-molecule inhibitors of K17. 2) Targeting K17 nuclear export: K17 impacts the nuclear export of ~50% of the proteome and depends on exportin-1 (XPO1). We found that K17+ PDAC cells were more sensitive to Selective Inhibitor of Nuclear Export (SINE) therapy, leading to a 2-fold increase in cell death compared to control cells, suggesting that nuclear export by K17 in PDAC cells could be therapeutically targeted. SINE therapy is currently FDA-approved for treatment of other cancer types and repurposing for the treatment of K17-positive PDACs may result in enhanced therapeutic efficacy. In conclusion, these studies provide the basis for the development of novel biomarker-based therapeutic approaches using small-molecule inhibitors, to target K17 active sites or the pathways altered by this protein in PDAC.

Citation Format: Cindy V. Leiton, Chun-Hao Pan, Ji Dong Bai, Lucia Roa-Peña, Sruthi Babu, Alex Penson, Nashaat Turkman, Richard Moffitt, Markus Seeliger, David Talmage, Kenneth R. Shroyer, Luisa F. Escobar-Hoyos. Therapeutic targeting of keratin 17 functional domains and nuclear export uncover therapeutic vulnerabilities of pancreatic cancer [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PO-040.

Altered RNA Splicing by Mutant p53 Activates Oncogenic RAS Signaling in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is driven by co-existing mutations in KRAS and TP53. However, how these mutations collaborate to promote this cancer is unknown. Here, we uncover sequence-specific changes in RNA splicing enforced by mutant p53 which enhance KRAS activity. Mutant p53 increases expression of splicing regulator hnRNPK to promote inclusion of cytosine-rich exons within GTPase-activating proteins (GAPs), negative regulators of RAS family members. Mutant p53-enforced GAP isoforms lose cell membrane association, leading to heightened KRAS activity. Preventing cytosine-rich exon inclusion in mutant KRAS/p53 PDACs decreases tumor growth. Moreover, mutant p53 PDACs are sensitized to inhibition of splicing via spliceosome inhibitors. These data provide insight into co-enrichment of KRAS and p53 mutations and therapeutics targeting this mechanism in PDAC.

Abstract B01: Validation of a novel cytologic biomarker for urothelial carcinoma

Introduction: Cytology and cystoscopy have limited sensitivity and specificity for the diagnosis of urothelial carcinoma (UC), due to inflammatory atypia, sampling errors, and other clinicopathologic factors that may obscure test results. Therefore, there remains a clinical need to identify biomarkers to improve the diagnostic accuracy to detect UC. Keratin 17 (K17) is an embryologic cytokeratin that functions as an oncoprotein to promote the degradation of tumor suppressors that drive tumorigenesis. Published work from our group established that K17 is highly expressed in UC and confirmed specificity for UC by immunohistochemical localization of K17 in tissue biopsies of both low-grade and high-grade UCs (Babu et al., Mod Pathol, 2018).

Objective: The objective of the current study was to develop an immunocytochemical (ICC) assay to determine K17 is a sensitive and specific biomarker to enhance diagnostic accuracy for UC in urine cytology.

Methods: 80 ThinPrep CytoLyt-fixed urine specimens, collected at Stony Brook Medicine in 2018, including 39 with a clinicopathologic diagnosis of UC based on current cytologic diagnosis, and/or a history of biopsy confirmed UC within one year (+/-) of urine cytology specimen collection. K17 ICC was performed by indirect immunoperoxidase methods and K17 test results were scored based on the detection of immunoreactive urothelial cells and not on an assessment of cytologic atypia. The sensitivity and specificity of urine K17 ICC for detection of urothelial neoplasia was calculated by comparison of ICC test results with the cytologic diagnosis and/or the histologic diagnosis of positive cystoscopic biopsy specimens (papillary urothelial neoplasm of low malignant potential [PUNLMP, n=1] or greater). Samples that had no history of abnormal urine cytologic or biopsy diagnosis were categorized as negative for urothelial neoplasia.

Results: Relative to the final clinicopathologic diagnosis of UC (n=38) or PUNLMP (n=1), K17 ICC had a sensitivity of 100% (95% CI: 91-100%) and specificity of 90% (95% CI: 77-96%). The positive predictive value was 90% (95% Cl: 78-96%) and the negative predictive value was 100% (95% Cl: 90-100%). Comparing ICC test results to cytologic and biopsy diagnoses, K17 ICC was positive in 9/23 (39%) cases with negative urine cytology. Of these 9 cases, 4 cases had biopsy confirmed UC. K17 ICC was positive in 4/11 (36%) of cases with inflammatory/reactive changes. Of these 4 cases, 3 had biopsy-confirmed UC. K17 ICC was positive in 14/30 (46%) of cases with mild atypia. Of these 14 cases, 12 had biopsy-confirmed UC and 1 had PUNLMP. K17 ICC was positive in 16/16 (100%) of cases with moderate atypia (n=8), severe atypia (n=3), or UC (n=5), all with biopsy-confirmed UC.

Conclusions: K17 ICC is a novel and highly sensitive and specific diagnostic test for underlying biopsy-confirmed UC among samples with inflammatory/reactive changes, cytologic atypia, or positive urine cytology. Thus, the K17 test could serve as an adjunct to guide the clinical management of UC cases.

Citation Format: Sruthi Babu, Lucia Roa-Peña, Ina Chan, Nam W. Kim, Sholeh Jahanfard, Luisa F. Escobar-Hoyos, Kenneth R. Shroyer. Validation of a novel cytologic biomarker for urothelial carcinoma [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr B01.

An unbiased high-throughput drug screen reveals a potential therapeutic vulnerability in the most lethal molecular subtype of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of cancer-related deaths in the United States by 2020, due in part to innate resistance to widely used chemotherapeutic agents and limited knowledge about key molecular factors that drive tumor aggression. We previously reported a novel negative prognostic biomarker, keratin 17 (K17), whose overexpression in cancer results in shortened patient survival. In this study, we aimed to determine the predictive value of K17 and explore the therapeutic vulnerability in K17-expressing PDAC, using an unbiased high-throughput drug screen. Patient-derived data analysis showed that K17 expression correlates with resistance to gemcitabine (Gem). In multiple in vitro and in vivo models of PDAC, spanning human and murine PDAC cells, and orthotopic xenografts, we determined that the expression of K17 results in a more than twofold increase in resistance to Gem and 5-fluorouracil, key components of current standard-of-care chemotherapeutic regimens. Furthermore, through an unbiased drug screen, we discovered that podophyllotoxin (PPT), a microtubule inhibitor, showed significantly higher sensitivity in K17-positive compared to K17-negative PDAC cell lines and animal models. In the clinic, another microtubule inhibitor, paclitaxel (PTX), is used in combination with Gem as a first-line chemotherapeutic regimen for PDAC. Surprisingly, we found that when combined with Gem, PPT, but not PTX, was synergistic in inhibiting the viability of K17-expressing PDAC cells. Importantly, in preclinical models, PPT in combination with Gem effectively decreased tumor growth and enhanced the survival of mice bearing K17-expressing tumors. This provides evidence that PPT and its derivatives could potentially be combined with Gem to enhance treatment efficacy for the ~ 50% of PDACs that express high levels of K17. In summary, we reported that K17 is a novel target for developing a biomarker-based personalized treatment for PDAC.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Abstract B50: Keratin 17 drives tumor aggression and could be targeted for treatment of pancreatic ductal adenocarcinoma

Our aims are to uncover the molecular mechanisms through which keratin 17 (K17), a prognostic biomarker, drives tumor aggression and to target these mechanisms to provide more effective treatment for pancreatic ductal adenocarcinoma (PDAC). In murine orthotopic xenografts, we found that K17-positve PDACs survive for a shorter interval than controls. Prompted by previous reports that post-translational modifications (PTMs) regulate intermediate filament dynamics, we established in vitro that phosphorylated K17 detaches from the cytoskeleton and enters the nucleus, where it promotes tumor growth by targeting tumor suppressor proteins, including p27, for nuclear export and degradation. To further understand the events that control K17 solubilization, we sequenced K17 from primary PDACs by liquid chromatography-mass spectrometry and identified serine sites within the N-terminus that are phosphorylated only in soluble K17. Furthermore, phosphorylation is required to maintain K17 solubility and soluble K17 accumulates in the nucleus of PDAC cells. By an unbiased screen of 80 small-molecule kinase inhibitors in PDAC, we determined that SYK kinase inhibitors, already in clinical trials for other malignancies, abrogated K17 solubilization. Prompted by our finding that K17 serves as a nuclear shuttle of p27, we identified two amino acid sequences in K17 that have similar polarity to sequences that are used by cyclins to dock to p27. Point mutations in two of these domain key residues blocked K17-mediated degradation of nuclear p27, and we identified similar effects in the background of wild-type and oncogenic KrasG12D PDAC cells. Current studies are under way to find additional protein and RNA targets for potential therapeutic intervention. Using patient-derived organoids, human and murine PDAC cells, we determined that K17-expressing PDAC cells are more than twice as resistant as isogenic K17-negative cells to gemcitabine (Gem) and 5-fluorouracil (5-FU), two key components of current chemotherapeutic regimens. By unbiased liquid chromatography-coupled tandem mass spectrometry metabolomics, RNA-sequencing analyses (TCGA), and in vivo magnetic resonance spectroscopy, we found that K17 induces metabolic reprogramming by increasing glycolysis and pyrimidine biosynthesis, pathways that have been linked to chemoresistance. We are extending this work to determine if disruption of K17-mediated metabolic rewiring by small-molecule inhibitors will resensitize tumor cells to pyrimidine analogues. In conclusion, K17 undergoes key post-translational modifications that enable solubilization and nuclear translocation, the targeting of tumor suppressor proteins, and enhanced pyrimidine biosynthesis to drive chemoresistance. Uncovering these mechanisms could ultimately lead to the identification of novel approaches to target the oncogenic functions of K17, and thereby, to enable the development of more effective treatment options for PDAC.

Citation Format: Kenneth R. Shroyer, Luisa Escobar-Hoyos, Cindy Leiton, Chun-Hao Pan, Ryan Kawalerski, Lucia Roa-Peña, Sruthi Babu. Keratin 17 drives tumor aggression and could be targeted for treatment of pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr B50.

Abstract C32: Therapeutic targeting of keratin 17 and nuclear export uncover therapeutic vulnerabilities of pancreatic cancer

The purpose of this study is to launch a novel biomarker-based targeted therapy that may result in improved precision and personalized medicine for pancreatic ductal adenocarcinoma (PDAC). We discovered that keratin 17 (K17), an intermediate filament (IF), is a nuclear oncoprotein found in 50% of PDAC cases, identifying the most aggressive and treatment-resistant form of PDAC and functioning as a biomarker. We set out to validate K17 as a druggable target and to identify K17-targeting mechanisms. In preclinical mouse models, animals bearing K17-expressing PDACs display the shortest survival interval, suggesting that K17 drives tumor aggression and is a potential therapeutic target. We used the following two approaches aimed to inhibit K17 nuclear shuttle functions in order to identify potential therapeutic strategies. 1) Targeting K17 functional domains: By protein-sequence modeling analyses and site-directed mutagenesis, we identified functional domains in K17 (K17-FDs) that bind to, shift the subcellular localization of, and promote the degradation of nuclear tumor suppressors (i.e., p27). Using SILAC mass spectrometry analysis of nuclear proteomes from isogenic human cells, we found that 80% of the nuclear proteome is altered by K17, that half of these proteins encode the domain targeted by the K17-FDs, and that a large proportion of these proteins are involved in gene expression. Animals harboring tumors with mutated K17-FDs lived two times longer than control animals, suggesting that the K17-FDs may be therapeutic targets. We are currently testing small-molecule and peptide inhibitors to target the K17-FDs in vitro and in vivo, as a discovery approach to design small-molecule inhibitors of K17. 2) Targeting K17 nuclear export: K17 impacts the export of ~50% of the proteome and depends on exportin-1 (XPO1) for nuclear export. We found that PDAC cells expressing K17 were more sensitive to Selective Inhibitor of Nuclear Export (SINE) therapy, leading to a 2-fold increase in cell death compared to control cells, suggesting that nuclear export is a necessary oncogenic pathway exploited by K17 in PDAC cells. SINE therapy is currently FDA approved for treatment of other cancer types, and repurposing for the treatment of K17-positive PDACs may result in enhanced therapeutic efficacy. In conclusion, these studies provide the basis for novel biomarker-based therapeutic approaches for the most aggressive PDAC cases using small-molecule inhibitors that directly target K17 active sites or the pathways altered by this protein.

Citation Format: Cindy V. Leiton, Chun-Hao Pan, Ji Dong Bai, Lucia Roa-Peña, Sruthi Babu, Alex Penson, Nashaat Turkman, Richard Moffitt, Markus Seeliger, David Talmage, Kenneth R. Shroyer, Luisa F. Escobar-Hoyos. Therapeutic targeting of keratin 17 and nuclear export uncover therapeutic vulnerabilities of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr C32.

Tuberculous lymphadenitis is associated with altered levels of circulating angiogenic factors

BACKGROUND

Angiogenic factors are important in granuloma formation and serve as biomarkers in pulmonary tuberculosis (PTB). The relationship between these markers and tuberculous lymphadenitis (TBL) is not known.

OBJECTIVE AND DESIGN

To examine the association of vascular endothelial growth factor (VEGF) and angiopoietin (Ang) family molecules in TBL, we measured systemic levels of VEGF-A, C, D, R1 (VEGF-receptor 1), R2, R3, Ang-1, Ang-2 and TIE2 (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) levels in TBL, latent tuberculous infection (LTBI) and lymph node culture supernatants (VEGF-A, C and Ang-2) of the same TBL patients.

RESULTS

Circulating levels of VEGF-A and VEGF-C were significantly diminished, whereas VEGF-R2, R3, Ang-2 and TIE2 levels were significantly increased, in TBL. Likewise, VEGF-A, C and Ang-2 levels were significantly increased in lymph node supernatants compared with plasma in individuals with TBL. Receiver operating characteristic curve analysis showed that VEGF-C and VEGF-R2 markers clearly distinguished TBL from LTBI. Following treatment, VEGF-C and Ang-1 levels were significantly altered. No association was observed between angiogenic factors and culture grade or lymph node size, except for VEGF-A. VEGF-A was also significantly decreased in multiple lymph nodes compared with single lymph nodes.

CONCLUSIONS

Our data suggest that altered levels of circulating angiogenic factors in TBL might reflect underlying vasculo-endothelial dysfunction. Reversal of angiogenic markers after anti-tuberculosis treatment suggests that these angiogenic markers may serve as biomarkers of disease severity or response to treatment in TBL.

Abstract P3-14-07: Evaluation of the effects of talazoparib on QT interval prolongation

Background: Talazoparib (TAL), an oral poly ADP-ribose polymerase inhibitor, is under investigation in multiple oncologic clinical trials and has been submitted to the US FDA for use in patients (pts) with germline BRCA-mutated, HER2-negative advanced breast cancer.

International Conference on Harmonisation guidance recommends all new drugs be evaluated for effects on cardiac repolarization in a well-controlled clinical study. For drugs for which such evaluation cannot be conducted in healthy volunteers (eg, most anticancer agents), collection of robust corrected QT (QTc) interval data from a dedicated QTc study (hybrid thorough QT/QTc study) in pts is required in the registration dossier. The effect of steady-state (ss) TAL (1 mg once daily) on cardiac repolarization in pts with advanced solid tumors was evaluated in an open-label phase 1 study (NCT03042910).

Methods: Continuous 12-lead electrocardiogram (ECG) recordings were collected at baseline (Day -1); time-matched pharmacokinetic (PK) samples and continuous ECG recordings were obtained on Days 1, 2, and 22 (when TAL concentrations achieved ss). On Day -1, pts had continuous 12-lead ECG recording starting at Time 0 (Day 1 dosing time) for 6 hrs. On Days 1 and 22, ECG recording started 45 min before TAL administration and continued for 6 hrs post dose and blood samples for PK were collected before dose and at 1, 2, 4, and 6 hrs post dose. On Day 2, a 30-min ECG recording and a PK sample were obtained before dose at Time 0.

Continuous ECG recordings were submitted to a central laboratory; triplicate 10-sec ECGs were extracted from a 5-min extraction window beginning 15 min before each PK collection time. ECG measurements were reported via blinded manual adjudication process and included PR interval, QT interval, RR interval, and QRS complex. The QT interval was corrected for effect of heart rate using Fridericia's correction (QTcF) and Bazett's correction (QTcB).

The estimate of change from time-matched baseline and its 2-sided 90% confidence interval (CI) was calculated for each nominal time point using PROC MEANS. Additionally, a prespecified PK/pharmacodynamic (PD) model was used to describe the relationship between plasma TAL concentrations ([TAL]) and QTc. The prespecified linear mixed-effects model included [TAL], time (categorical), and treatment with random pt effects on [TAL] and the intercept. If the upper bounds (UB) of 1-sided 95% CIs of time-matched ΔQTc for all ECG time points were &lt;20 msec and the UB of 1-sided 95% CIs of the predicted ΔQTc at the mean ss maximum [TAL] was &lt;20 msec, the effect of TAL on QTc was not of clinical relevance.

Results: 37 of 38 pts enrolled received TAL and were included in the ECG and PK/PD analyses. No pts had a postbaseline absolute maximum QTcF or QTcB ≥500 msec or ΔQTc ≥60 msec. The UB of the 1-sided 95% CI for the time-matched ΔQTcF and ΔQTcB were &lt;12 msec at all nominal ECG time points. In the PK/PD analysis, the slopes (95% CI) of QTcF-[TAL] and QTcB-[TAL] relationships were -0.14 (-0.78 to 0.50) msec/ng/mL and -0.24 (-0.88 to 0.41) msec/ng/mL, respectively, indicating that TAL did not have a concentration-dependent effect on QTcF or QTcB.

Conclusion: TAL does not have a clinically relevant effect on QTc.

Funding: Medivation LLC, acquired by Pfizer.

Citation Format: Hoffman J, Chakrabarti J, Wainberg ZA, Plotka A, Babu S, Milillo Naraine A, Kanamori D, Moroose R, Nguyen L, Wang D. Evaluation of the effects of talazoparib on QT interval prolongation [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-14-07.

The Significance of ERG and Androgen Receptor Expression in Adenocarcinoma Prostate

Background Fusions of transmembrane protease, serine 2 (TMPRSS2) with erythroblast transformation specific transcription factors have been found in prostate cancer. The v-etserythroblastosis virus E26 oncogene homologue (ERG) is a proto-oncogene of the erythroblast transformation specific transcription factor family. TMPRSS2-ERG fusion is the most common molecular alteration present in about 50% of prostatic adenocarcinomas. Androgen receptor (AR) plays a key role in prostate development and is involved in the progression of prostate cancer. Objective To evaluate the significance of combined ERG and AR expression in cases of prostatic adenocarcinoma. Method The study was conducted at Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India. Formalin fixed-paraffin embedded archival prostatic tissue specimens were obtained. A total of 10 cases of prostatic adenocarcinoma were included in the study. Immunohistochemistry for Androgen receptor was done by the standard protocol. Multiplex immunohistochemical staining was done for ERG+CK5 using a primary antibody cocktail of mouse and rabbit antibodies. Result Specific AR immunostaining was exclusively nuclear and was present in all 10 cases in varying intensity. Specific ERG immunostaining was nuclear and was present in seven cases (70%) and absent in three cases (30%). The three cases that were negative for ERG had a Gleason score of ≤ 6 and the AR staining was strong and present in about 90% of the cells. Gleason score was directly related to the ERG staining while AR staining was inversely related to the ERG staining. Conclusion The prognostic value of combined ERG and AR over-expression, its associated genes should be further investigated as potential therapeutic targets in prostate cancer progression. Preliminary data is being presented. Larger prospective studies with survival analysis are essential for prognostic significance.

Status of raptors in the Moyar River Valley, Western Ghats, India

This study examined the species composition and nest-tree characteristics of diurnal raptors in the tropical forests of Moyar Valley, Western Ghats between December 2012 and March 2013.  We recorded 28 species of raptors including three species of vultures.  Accipitridae was the dominant family comprising of 25 species followed by two from Falconidae and the monotypic Pandionidae.  Among them, eight species fall under various threatened category: three Critically Endangered, one Endangered, two Vulnerable and two Near Threatened.  The Critically Endangered Gyps bengalensis was frequently recorded during the survey (175 sightings) followed by Milvus migrans (39 sightings) and Haliastur indus (27 sightings).  We located 53 active nests of four species of raptors, viz., Gyps bengalensis (42 nests), Nisaetus cirrhatus (4 nests), Haliastur indus (4 nests), and Milvus migrans (3 nests).  A notable difference in the nest-tree characteristics among the sympatric raptors was observed.  These results would be important to identify priority areas for developing future conservation and management programs for the long-term conservation of raptorial birds in the Western Ghats.

Angiopoietins as biomarkers of disease severity and bacterial burden in pulmonary tuberculosis

BACKGROUND

Circulating angiogenic factors of the vascular endothelial growth factor family are important biomarkers of disease severity in pulmonary tuberculosis (PTB). However, the role of angiopoietins, which are also involved in angiogenesis, in PTB is not known.

OBJECTIVE AND DESIGN

To examine the association of circulating angiopoietins with TB disease or latent tuberculous infection (LTBI), we examined the systemic levels of angiopoietin (Ang) 1, Ang 2 and Tie-2 receptor in individuals with PTB (n = 44), LTBI (n = 44) or no tuberculous infection (NTBI) (n = 44).

RESULTS

Circulating levels of Ang-1, Ang-2 and Tie-2 were significantly higher in PTB than in individuals with LTBI or NTBI. Moreover, Ang-1, Ang-2 and Tie-2 levels were significantly higher in PTB with bilateral disease. The levels of these factors also exhibited a significant positive relationship with bacterial burdens in PTB. Receiver operating characteristics curve analysis revealed Ang-2 as a marker distinguishing PTB from LTBI or NTBI. Finally, the circulating levels of Ang-1, Ang-2 and Tie-2 were significantly reduced following anti-tuberculosis chemotherapy.

CONCLUSIONS

Our data demonstrate that PTB is associated with elevated levels of circulating angiopoietins, possibly reflecting endothelial dysfunction. In addition, Ang-2 could prove useful as a biomarker to monitor disease severity, bacterial burden and therapeutic responses.

Xanthogranulomatous Pyelonephritis: Intrahepatic and Intrathoracic Extension

A 32-year-old female presented to us with worsening cough and expectoration, low-grade fever, and malaise for 3 months. She gave a history of pregnancy loss secondary to urinary tract infection (UTI) a year back. At that time, she was told to have an obstructive right renal calculus. She also had a history of recurrent UTI in the past 1 year. She had no other comorbidities. Her clinical evaluation revealed an enlarged right kidney and reduced air entry in the right hemithorax. Radiological investigations revealed a large right kidney invading into the inferior surface of the right lobe of the liver and the right pleural space. A clinical diagnosis of xanthogranulomatous pyelonephritis was made, and she was advised nephrectomy. Intraoperatively, the right kidney was found to invade both the right lobe of the liver and the right pleural cavity through a right diaphragmatic defect. Histopathology of the kidney revealed the presence of foamy histiocytes suggestive of xanthogranulomatous pyelonephritis. Invasive xanthogranulomatous pyelonephritis is known, however, invasion into the extra-abdominal structures has not been reported in the literature. Our case is a rare manifestation of a rare clinical entity – xanthogranulomatous pyelonephritis.

Accumulation of phytoene, a colorless carotenoid by inhibition of phytoene desaturase (PDS) gene in Dunaliella salina V-101

The aim of this work was to study the accumulation of phytoene in Dunaliella salina V-101 by down-regulating its phytoene desaturase (PDS) gene expression using RNA interference and Antisense technology. RNAi and antisense constructs were introduced into the Dunaliella cells by Agrobacterium-mediated transformation. Among thirty-two transformants, six showed positive down-regulation of PDS expression with RNAi construct and five positive transformants were obtained using antisense construct. Characterization of PDS suppression was carried out using semi-quantitative RT-PCR and quantitative determination of phytoene as well as other carotenoids by HPLC. Both the RNAi and antisense lines showed a significant decrease in the expression levels of phytoene desaturase and carotenoid content compared to wild type cells. The RNAi line #5 showed maximum Phytoene content (108.34±22.34µg/100mg DCW) compared to other transgenic lines. These phytoene-accumulating phenotypes exhibited slower growth rates and were found to be sensitive to high light conditions.