Impact of pregnancy vaccine uptake and socio-demographic determinants on subsequent childhood Measles, Mumps and Rubella vaccine uptake: A UK birth cohort study

BACKGROUND

We examined the association between socio-demographic determinants and uptake of childhood Measles, Mumps & Rubella (MMR) vaccines and the association between pregnant women's pertussis vaccine uptake and their children's MMR vaccine uptake.

METHODS

We used nationally-representative linked mother-baby electronic records from the United Kingdom's Clinical-Practice-Research-Datalink. We created a birth cohort of children born between 01.01.2000 and 12.12.2020. We estimated the proportion vaccinated with first MMR vaccine by age 2 years and first and second MMR vaccines by age 5 years. We used survival-analysis and Cox proportional hazard models to examine the association between deprivation, ethnicity and maternal age and pertussis vaccination in pregnancy and children's MMR uptake.

RESULTS

Overall, 89.4 % (710,797/795,497) of children had first MMR by age 2 years and 92.6 % (736,495/795,497) by age 5 years. Among children still in the cohort when second MMR was due, 85.9 % (478,480/557,050) had two MMRs by age 5 years. Children from the most-deprived areas, children of Black ethnicity and children of mothers aged < 20 years had increased risk of being unvaccinated compared with children from the least-deprived areas, White children and children of mothers aged 31-40 years: first MMR by 5 years, adjusted Hazard Ratios (HR):0.86 (CI:0.85-0.87), HR:0.87 (CI:0.85-0.88) & HR:0.89 (CI:0.88-0.90) respectively. Deprivation was the determinant associated with the greatest risk of missed second MMR: adjusted HR:0.82 (CI:0.81-0.83). Children of mothers vaccinated in pregnancy were more likely than children of unvaccinated mothers to have MMR vaccines after adjusting for ethnicity, deprivation, and maternal age (First and Second MMRs adjusted HRs:1.43 (CI:1.41-1.45), 1.49 (CI:1.45-1.53).

CONCLUSION

Children from most-deprived areas are less likely to have MMR vaccines compared with children from least-deprived areas. Mothers who take up pregnancy vaccines are more likely to have their children vaccinated with MMR. Healthcare services should promote and facilitate access to both maternal and childhood vaccines during pregnancy.

Diagnostic performance of saliva RT-PCR test as a diagnostic tool and its utility in the detection of SARS-CoV-2 shedding with different patient characteristics: Prospective observational study

BACKGROUND

Salivary shedding of SARS-CoV-2 is a known entity and its role has been established in transmission of the disease. The present study was performed to evaluate the duration of viral shedding in saliva in COVID-19 patients and its variation among symptomatic and asymptomatic patients with or without co-morbidities.

METHODS

The present prospective observational study was conducted at the COVID-19 care hospital associated with primary to tertiary care in New Delhi, India. A total of 124 COVID-19 confirmed cases enrolled in two phases (January-March 2021; April-June 2021) who consented for 48hrly saliva and nasopharyngeal swab (NPS) specimens till discharge from the hospital for SARS-CoV-2 detection were included. The specimens obtained were tested for SARS-CoV-2 by Real-Time PCR.

RESULTS

The sensitivity and the specificity of RT-PCR on saliva were 81.7 ​% and 85.0 ​%, respectively. The sensitivity of saliva-based PCR was comparable in symptomatic and asymptomatic patients (81.6 ​% vs 82.1 ​%). The sensitivity of saliva-based PCR markedly increased in the second phase of enrollment as compared to the first phase (92.6 ​% vs 78.5 ​%) indicating higher level of salivary shedding by the delta variant of SARS-CoV-2. The sensitivity of PCR on saliva was the highest up to day seven of illness. The median duration of RNA shedding in saliva was comparable among the symptomatic and asymptomatic patients. The severity of the disease was not associated with the duration of SARS-CoV-2 shedding in saliva.

CONCLUSIONS

SARS-CoV-2 shedding in saliva continued till seven days in large number of patients including asymptomatic patients. Saliva is non-inferior to NPS specimen in the diagnosis of SARS-CoV-2. Saliva specimen is recommended as a good alternate to NPS for SARS-CoV-2 testing.

Small molecule antagonist of CXCR2 and CXCR1 inhibits tumor growth, angiogenesis, and metastasis in pancreatic cancer

Pancreatic cancer (PC) has a poor prognosis, and current therapeutic strategies are ineffective in advanced diseases. We and others have shown the aberrant expression of CXCR2 and its ligands in PC development and progression. Our objective for this study was to evaluate the therapeutic utility of CXCR2/1 targeting using an small molecule antagonist, SCH-479833, in different PC preclinical murine models (syngeneic or xenogeneic). Our results demonstrate that CXCR2/1 antagonist had both antitumor and anti-metastatic effects in PC. CXCR2/1 antagonist treatment inhibited tumor cell proliferation, migration, angiogenesis, and recruitment of neutrophils, while it increased apoptosis. Treatment with the antagonist enhanced fibrosis, tumor necrosis, and extramedullary hematopoiesis. Together, these findings suggest that selectively targeting CXCR2/1 with small molecule inhibitors is a promising therapeutic approach for inhibiting PC growth, angiogenesis, and metastasis.

How did the covid-19 pandemic affect lower respiratory tract infections in young children in England?

Background

Social distancing policies to reduce transmission of covid-19 also reduced children's exposures to endemic respiratory viruses. We aimed to examine the impact of the covid-19 pandemic on lower respiratory tract infections in under 5s presenting to primary care in England.

Methods

Longitudinal trends analysis using electronic health records from a nationally representative primary care database. Our target population was children aged &lt;5 years registered with a primary care practice from January 2015 to March 2021.

Our main outcome was total weekly contacts with primary care for a lower respiratory tract infection (LRTI). We defined three pandemic phases from March 2020 - March 2021: i) first national lockdown (late March to early June 2020), ii) childcare settings reopened and second national lockdown with schools open (mid-June to mid-December 2020) and iii) third national lockdown with schools closed (late December 2020 to end of March 2021). We compared outcomes during each of the three phases with corresponding calendar weeks during pre-pandemic years 2015 to 2019.

Results

Our study population included 843 020 children &lt;5 years who had 1 076 181 contacts with primary care for LRTIs. During the first phase (first lockdown) there were falls of 79.3% (95% CI: 73.6 to 84.5) from an average of 28 547 primary care contacts for LRTI in 2015 - 2019 to 5915 in 2020; there was a 78.9% (95% CI: 73.7 to 83.9) fall in phase two (childcare settings reopened and second lockdown) from 107 873 to 22 792 contacts; and a 77.7% (95% CI: 73.5 to 81.4) fall in phase three (third lockdown) from 57 200 to 12 764 contacts.

Conclusions

Children under 5 in England had fewer contacts with primary care for LRTIs during the covid-19 pandemic. This change likely reflects lower prevalence of respiratory illness due to fewer social contacts. This may impact on future health service use as these children have had less exposure, and therefore may have less immunity, to respiratory diseases.

Key messages

• Children under 5 had fewer contacts with primary care for lower respiratory tract infections during the covid-19 pandemic in England likely due to the restrictions in place to reduce social contacts.

• The falls in lower respiratory tract infections during the covid-19 pandemic in under 5s may mean they have less immunity to respiratory viruses which may impact upon their future health service use.

The use of EPR spectroscopy to study transcription mechanisms

Electron paramagnetic resonance (EPR) spectroscopy has become a promising structural biology tool to resolve complex and dynamic biological mechanisms in-vitro and in-cell. Here, we focus on the advantages of continuous wave (CW) and pulsed EPR distance measurements to resolve transcription processes and protein-DNA interaction. The wide range of spin-labeling approaches that can be used to follow structural changes in both protein and DNA render EPR a powerful method to study protein-DNA interactions and structure-function relationships in other macromolecular complexes. EPR-derived data goes well beyond static structural information and thus serves as the method of choice if dynamic insight is needed. Herein, we describe the conceptual details of the theory and the methodology and illustrate the use of EPR to study the protein-DNA interaction of the copper-sensitive transcription factor, CueR.

P302 Disseminated histoplasmosis: Rare entity in immunocompromised individuals in India

 

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

Invasive mycoses kill more than one million people every year. The disease burden of mycoses has increased over the last 20 years and the importance of fungal disease is expected to keep increasing in the years to come. One of these mycoses, histoplasmosis, a disease caused by species of dimorphic genera, Histoplasma and is endemic in the USA, Asia, and Africa with sporadic cases reported from India. In the United States alone, 3.4 cases/100 000 people occur yearly. In India, prevalence of histoplasmosis is seen in the eastern part of the country and few cases are reported from north India. Here, we present four cases of classic progressive disseminated histoplasmosis from non-endemic central and northern parts of India.

Cases I and II: Two cases, firstly a 51-year-old male resident of Delhi, came with complaints of fever, generalized weakness and weight loss for the past 6 months, and another a 55-year-old in an apparently immunocompetent female from a non-endemic state in central India. The disease was diagnosed by bone marrow aspirate incidentally.

Cases III and IV: A 25-year-old female and a 29-year-old HIV-infected female, with chief complaints of multiple skins colored swellings on her face, neck, chest, and back and also on both limbs. Physical examination revealed multiple skin-colored papules and nodules coalescing to form large plaques on the face, neck, upper back, and chest which had overlying yellowish-brown crusting (Fig.1). Her entire face was involved with depression of the nasal bridge and madarosis. Multiple discrete 0.1-0.5 mm papules and nodules on bilateral upper and lower limbs. Patient was started on the treatment of cutaneous histoplasmosis with injection of liposomal amphotericin-B 100 mg intravenous (around 3 mg/kg/day) after pre-medication for 10 days. For both cases, capsule itraconazole 200 mg BD started for 4 days. Patient responded well to the treatment and follow-up showed improvement in the condition of the patient.

Results

In all the cases, fine needle aspirate cytology of the lesions showed plenty of inflammatory cells and macrophages in pathological microscopic examination. Microscopic examination of skin tissue revealed that macrophages comprising of yeast forms of Histoplasma have pericellular halo around them. Moreover, on long incubation of biopsy sample on SDA media plate at 27˚C, white/buff colonies with yellow-tan on the back were observed. Furthermore, microscopic examination of grown fungal culture showed mycelial septate hyphae bearing round to pear-shaped, smooth-walled broadly elliptical microconidia, or tuberculate macroconidia. In all the cases, clinical suspicion, histopathological and mycological findings (microscopy, culture and post-culture sequencing) led to a confirmatory diagnosis of progressive disseminated Histoplasmosis by H. capsulatum var. capsulatum was made.

Conclusion

In all, 3 of these cases are of progressive disseminated histoplasmosis in apparently immunocompetent patients from the non-endemic states of north India. On the contrary, one of the cases was HIV positive with mucocutaneous lesions. Disseminated histoplasmosis in immunocompetent individuals is not a rare entity, in India. High clinical suspicion and awareness regarding the pathogen are required. From the point of good patient care, an accurate diagnosis, and timely management in cases of histoplasmosis are warranted.

Alien genome mobilization and fixation utilizing an apomixis mediated genome addition (AMGA) strategy in Pennisetum to improve domestication traits of P. squamulatum

An approach to release 'frozen' variability in apomictic species using sexuality of another species, eventually its utilization in crop improvement and de-novo domestication of crop wild relatives is presented. Pennisetum squamulatum, a secondary gene pool species of pearl millet (P. glaucum), harbours many desirable traits. However, it was neither utilized to improve pearl millet fodder traits nor improvement of its own domestication traits was attempted, due to the complexities of genomes and apomictic reproduction. To overcome this, we followed an Apomixis Mediated Genome Addition (AMGA) strategy and utilized the contrasting reproductive capacities (sexuality and apomixis) of both the species to access the otherwise un-available variability embedded in P. squamulatum. Segregating population of interspecific hybrids exhibited significant variability and heterosis for desired morphological, agronomical, and nutritional traits. Elite apomictic and perennial hybrids were evaluated in breeding trials, and eventually a novel grass cultivar was released for commercial cultivation in India. The performance of newly developed cultivar was superior to other adapted perennial grasses of arid and semi-arid rangelands. Through AMGA, the sexuality of one species was successfully utilized to 'release' the 'frozen' variability embedded in another species. Subsequently, the hybrids representing desirable trait combinations were again 'fixed' utilizing the apomixis alleles from the male parent in a back-and-forth apomixis-sexual-apomixis selection cycle. This study also demonstrated the potential of AMGA to improve crop relatives through genomes introgression as well as de novo domestication of new crops from wild species.

Differential expression profile of CXC-receptor-2 ligands as potential biomarkers in pancreatic ductal adenocarcinoma

The discovery of early detection markers of pancreatic cancer (PC) disease is highly warranted. We analyzed the expression profile of different CXC-receptor-2 (CXCR2) ligands in PC cases for the potential of biomarker candidates. Analysis of different PDAC microarray datasets with matched normal and pancreatic tumor samples and next-generation sequenced transcriptomics data using an online portal showed significantly high expression of CXCL-1, 3, 5, 6, 8 in the tumors of PC patients. High CXCL5 expression was correlated to poor PC patient survival. Interestingly, mRNA and protein expression analysis of human PC cell lines showed higher CXCL2, 3, and 5 expressions in cell lines derived from metastatic sites than primary tumors. Furthermore, we utilized immunohistochemistry (IHC) to evaluate the expression of CXCR2 ligands in the human PC tumors and observed positive staining for CXCL1, 3, and 8 with a higher average IHC composite score of CXCL3 in the PC tissue specimens than the normal pancreas. We also observed an increase in the expression of mouse CXCL1, 3, and 5 in the pre-cancerous lesions of tumors and metastasis tissues derived from the PDX-cre-LSL-Kras^G12D mouse model. Together, our data suggest that different CXCR2 ligands show the potential of being utilized as a diagnostic biomarker in PC patients.

Are children at schools registered to The Daily Mile™ more physically active?

Background

The Daily Mile (TDM) is among the most popular school-based running programmes recommended globally by governments and the WHO to meet the shortfalls in children's physical activity. In England, it has been adopted by 1 in 5 primary schools. However, its impact on children's physical activity has not been assessed at scale. We aimed to compare a)minutes (mins) of moderate to vigorous physical activity (MVPA) in and outside school hours and b)meeting physical activity guidelines in primary school children in England, comparing those in schools registered with TDM with those that were not.

Methods

This was a cross-sectional study. We used self-reported data of 49,561 English primary school children(5-11 years) from the Active Lives Children and Young People Survey and TDM registration data of their school. We compared mins of MVPA in and outside school hours between children in TDM-registered and non-registered schools using a multilevel zero-inflated negative binomial model; and the differences in the likelihood of meeting physical activity guidelines based on TDM registration with a multilevel logistic regression model. All models included a random effect for school and adjusted for potential confounders.

Results

Children attending TDM-registered schools reported an extra 36 mins of MVPA a week overall, including 10 additional mins (95%CI:3,16) MVPA/week during school hours and 26 additional (95%CI:4,44) mins MVPA/week outside school hours. Children in TDM-registered schools were 6% more likely to meet physical activity guidelines compared to those who were not(RR:1.06 (95%CI:1.02,1.11)).

Conclusions

Children in primary schools registered to TDM report more physical activity that is not compensated for outside school hours. However, the absolute differences fall considerably short of international guidelines across the whole child population. Therefore, a whole school and systems-based approach is required, embedding school-based running programmes.

Key messages

Children in schools registered to TDM report more MVPA overall, inside, and outside school hours; suggesting no compensation of activity in those who are registered. TDM is a potential solution to increase children’s physical activity during the school day.

Internalized weight bias in the relationship between mental health and obesity in UK adolescents

Background

It is crucial to promote mental and physical health during adolescence to protect against lifetime risks of mental health problems and obesity. Internalized weight bias (self-directed stigmatizing attitudes about perceived weight status) and bullying are implicated as potential mechanisms in the relationship between mental health and obesity in adolescence. We examined internalized weight bias and bullying as potential mediators of the relationship between mental health and weight status across adolescence in the United Kingdom (UK).

Methods

We analysed data on 8,688 adolescents from the UK Millennium Cohort Study. Weight status was defined using sex and age specific International Obesity Taskforce cut points for body-mass index (not overweight/obese; overweight; obese) at 11 and 17 years. Mental health was defined using parental reported emotional (anxiety and depression), and externalizing (aggression and impulsivity) symptoms at 11 and 17 years (low; moderate; high). Self-reported measures of internalized weight bias captured via body-dissatisfaction and self-esteem and bullying at 14 years were tested as mediators. We used Generalized Structural Equation Models to examine longitudinal pathways between weight status and mental health across 11 and 17 years, whilst accounting for concurrent associations and potential confounders.

Results

Adolescents with high emotional (relative risk (RR) 1.98, 95% CI 1.28 to 3.07) or externalizing symptoms (RR 2.07, 95% CI 1.23 to 3.48) at 11 years were twice as likely to be obese at 17 years compared with those who had low symptoms. The impact of emotional and externalizing symptoms on weight status was found to be partially attributable to internalized weight bias, but not bullying, with significant mediation for body-dissatisfaction and low self-esteem.

Conclusions

Internalized weight bias partially explains the relationship between mental health and weight status across adolescence.

Key messages

There is a need for a holistic, early prevention strategy to focus on reducing weight stigma to encourage healthy mental and physical development of children. The relationship between mental health and weight status across adolescence is partly attributable to internalized weight bias.

A core outcome set for school-based physical activity interventions: an international consensus

Background

Studies of school-based physical activity interventions vary in the outcomes they measure. This prevents comparisons of results to establish impacts. We aimed to develop a core outcome set agreed by key stakeholders for future studies of school-based physical activity interventions.

Methods

We used a modified-Delphi consensus method. First, we conducted a systematic review to identify outcomes measured in relevant studies and listed these in a Delphi survey. Next, we recruited key stakeholders to complete 2 survey rounds: Round 1 was to rate each outcome from ‘not important' to ‘critical', and Round 2 was to re-rate the outcomes based on feedback from Round 1. Outcomes rated ‘critical' by 70% of stakeholders (i.e., reaching consensus) were highlighted. Then, using the full list of outcomes, we conducted a children's workshop to include their views. Finally, we held a stakeholder meeting to discuss results and agree consensus.

Results

We identified 50 outcomes from the systematic review. Sixty-five stakeholders (16 educators, 13 health professionals, 12 parents, 24 researchers) representing 9 countries completed both survey rounds; 13/50 outcomes reached consensus. Children (n = 16) identified 8 outcomes of importance; 3 were consistent with the survey results. Stakeholders attending the meeting (n = 13) reached consensus on 14 outcomes to be included in the core outcome set: fitness, physical activity intensity, energy, sleep, diet, happiness, stress, depression, anxiety, wellbeing, self-esteem, enjoyment, concentration, and focus. These core outcomes were reviewed and agreed by all 65 stakeholders.

Conclusions

Our core outcome set agreed by international stakeholders includes physical and mental health, and cognitive function. We recommend its use in future studies of school-based physical activity interventions. Findings from future studies can be compared and combined which will be relevant to public health policy makers and educators.

Key messages

School-based physical activity interventions should measure physical and mental health, and cognitive function. Wide use of this core outcome set will enable findings to be compared and combined.

Implementation of The Daily Mile™: survey of primary schools in Greater London

Background

The Daily Mile™ is a free school-based active mile intervention. Its main features include that children run or jog for 15 minutes at least 3 times a week (3x/wk) during school hours. The Daily Mile Foundation recommends 10 principles for successful implementation. These are it is (1) quick (15 minutes), (2) fun, (3) whole school participates, (4) it takes place in all weathers, (5) 3x/wk in addition to curricular lessons (not during PE, breaks, before/after school), (6) ideally in the school playground, (7) safe, (8) simple (no equipment), (9) children go at their own pace and (10) no change of clothes or shoes is needed. The aim of this study was to identify how many Greater London primary schools adopting The Daily Mile implement its 10 principles.

Methods

In September 2020, we sent all state-funded primary schools (n = 1721) in every Greater London borough (n = 32) a survey to find out if and how they implemented The Daily Mile.

Results

By June 2021, 368 (21%) schools responded to our survey (at least one from every London borough). Of these, 195 (53%) schools adopted The Daily Mile of which only 7 (4%) reported implementing all 10 principles; a median 7 (IQR: 6,8) principles were reported implemented. Whole school participation was reported by 93 (48%) Daily Mile schools, 104 (53%) reported implementing The Daily Mile for 15 minutes, 127 (65%) implemented it at least 3x/wk, and 149 (76%) schools reported that the children ran or jogged during The Daily Mile. A large proportion of schools reported implementing The Daily Mile in the school playground and that it was done simply (both n = 171, 88%), but only 85 (44%) schools reported implementing it during lessons.

Conclusions

Daily Mile schools in Greater London implement 7/10 principles on average. Whether implementing all the principles limits the success of its desired effect is unclear. Studies assessing effects of The Daily Mile should consider its implementation when reporting results.

Key messages

Of The Daily Mile’s 10 principles, an average of 7 are implemented in London schools. Studies examining The Daily Mile should consider implementation which may impact its desired effect.

Abstract 1087: CXCR2 and its ligands modulate chemotherapy resistance in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) has one of the lowest survival rates of cancers, with a five-year relative survival of 9%. The significant factor contributing to low survivorship is the intrinsic resistance to chemotherapy. In the present study, we elucidate a targetable pathway that facilitates resistance in these cells. One inflammatory pathway used in cancer progression is CXCR2, which binds chemokines CXCL 1-3 and 5-8. Our group and others have shown an association of CXCR2 with tumor progression, angiogenesis and metastasis in PDAC, and chemotherapy resistance in other cancers. In this study, we test the hypothesis that CXCR2 is integral in PDAC chemotherapy resistance. We generated gemcitabine resistant cell lines (GemR) from the parent cell lines of T3M4 (WT KRAS) and CD18/HPAF (Mutant KRAS) with 40- and 67-fold higher resistance in comparison to the parent cell lines, respectively. Using qRT-PCR and ELISA, we profiled chemokines' expression, CXCL1, 5, and 8, on parent- and GemR-cell lines. We observed a higher basal level expression of CXCL1, 5, and 8 ligands in GemR cells than the parent cell lines. Further treatment with gemcitabine, the parent cell lines had a higher increase in CXCL1 and 8 ligand expression in comparison with GemR cell lines. With further investigation of T3M4, we found a dose-dependent and time-dependent increase for CXCL1 and CXCL8. CXCL5 had a constant high expression with all doses of gemcitabine. With our initial observations of gemcitabine treatment enhancing CXCR2 ligands in PDAC cells, we evaluated the effects of the small molecule CXCR2 antagonist SCH 479833 (SCH 47) in combination with gemcitabine treatment on the parent and GemR cell lines. We used the relative IC50 and half the relative IC50 for both the gemcitabine and SCH 47 treatment doses. We observed that a lower concentration of gemcitabine in the presence of the SCH 47 was more effective than the higher concentration of gemcitabine without SCH 47 for the GemR-cell lines. Together, our observations show chemotherapy-resistant PDAC cell lines express higher CXCR2 ligand levels at baseline, with parent cell lines increasing expression with chemotherapy treatment. We also show an advantageous combination treatment of CXCR2 antagonist with lower gemcitabine concentration. Overall, these results show a promising future for CXCR2 antagonism in the treatment of resistant PDAC tumors.

Citation Format: Caitlin Molczyk, Dipakkumar R. Prajapati, Sugandha Saxena, Paran Goel, Michelle Varney, Rakesh K. Singh. CXCR2 and its ligands modulate chemotherapy resistance in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1087.

Abstract 3196: Soluble factors released by pancreatic cancer cells enhance neutrophil survival

Pancreatic cancer (PC) remains a challenge to modern-day cancer therapeutics, with a dismal five-year survival rate of 10%. Due to the pancreas' tricky location and the dense stroma surrounding it, patients have late diagnosis and fail to respond to chemotherapy regimens. The genetic stability of the tumor microenvironment (TME) in comparison with rapidly evolving tumor cells makes it an attractive target for the development of cancer therapeutics. Neutrophils, the most abundant immune cell, is an essential player in the TME. These neutrophils can become pro-tumorigenic based on signals they receive in the TME by regulating immune suppression, tumor metastasis, and angiogenesis. Previous studies from our laboratory demonstrate an increase in the number of neutrophils in the pancreatic tumor with the PC disease's progression in the KPC Model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre). Based on our previous observation and accumulating literature, we hypothesize that pancreatic tumor cells can increase neutrophil proliferation and/or survival in circulation and tumor in situ. We investigated the effect of soluble factors released by pancreatic tumor cells on neutrophil proliferation/survival with this rationale. For this objective, we utilized murine promyelocytes cells (MPRO), a mouse neutrophil cell line, and a human leukemia cell line (HL60), a human neutrophil cell line. We treated MPRO and HL60 cells with a gradient of supernatants collected from T3M-4- and CD18/HPAF-parent and gemcitabine-resistant cells. By utilizing the WST assay, we observed an increase in MRPO and HL60 cells' viability with an increasing gradient of supernatant collected from both T3M-4, CD18/HPAF-parent gemcitabine-resistant cells with serum-free media as a control. We also observed a slight increase in neutrophil viability when treated with the supernatant collected from parent cell-lines supernatant compared to supernatant collected from the gemcitabine resistant cell-lines. Next, to delineate the effect of direct interaction between pancreatic tumor cells and neutrophils, we utilized a co-culture assay between MPRO cells and CD18/HPAF cells. We observed an increase in the viability of CD18/HPAF cells when placed in contact with the neutrophils; however, we observed inhibition in the viability of neutrophils placed in contact with the tumor cells. Our results showing positive viability of neutrophils with the treatment of soluble tumor factors explain higher neutrophil to lymphocyte ratio in PC patients' blood circulation. Neutrophils in the TME release pro-tumorigenic cytokines that increase tumor cell proliferation, albeit resulting in neutrophil death as observed by neutrophil growth inhibition. Along with neutrophil survival, a more mechanistic understanding of neutrophil recruitment and polarization in TME will facilitate designing novel therapeutics for PC.

Citation Format: Paran Goel, Sugandha Saxena, Caitlin Molczyk, Rakesh Singh. Soluble factors released by pancreatic cancer cells enhance neutrophil survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3196.

Chemokines orchestrate tumor cells and the microenvironment to achieve metastatic heterogeneity

Chemokines, a subfamily of the cell cytokines, are low molecular weight proteins known to induce chemotaxis in leukocytes in response to inflammatory and pathogenic signals. A plethora of literature demonstrates that chemokines and their receptors regulate tumor progression and metastasis. With these diverse functionalities, chemokines act as a fundamental link between the tumor cells and their microenvironment. Recent studies demonstrate that the biology of chemokines and their receptor in metastasis is complex as numerous chemokines are involved in regulating site-specific tumor growth and metastasis. Successful treatment of disseminated cancer is a significant challenge. The most crucial problem for treating metastatic cancer is developing therapy regimes capable of overcoming heterogeneity problems within primary tumors and among metastases and within metastases (intralesional). This heterogeneity of malignant tumor cells can be related to metastatic potential, response to chemotherapy or specific immunotherapy, and many other factors. In this review, we have emphasized the role of chemokines in the process of metastasis and metastatic heterogeneity. Individual chemokines may not express the full potential to address metastatic heterogeneity, but chemokine networks need exploration. Understanding the interplay between chemokine-chemokine receptor networks between the tumor cells and their microenvironment is a novel approach to overcome the problem of metastatic heterogeneity. Recent advances in the understanding of chemokine networks pave the way for developing a potential targeted therapeutic strategy to treat metastatic cancer.

Efficacy and tolerability of eslicarbazepine acetate as monotherapy in patients of newly diagnosed focal epilepsy

Introduction

Eslicarbazepine Acetate, a novel anti-epileptic drug has been approved as monotherapy in focal onset seizures, with/without secondary generalization in adults. Eslicarbazepine has many advantages over older anti-epileptic drugs and is useful in patients of new onset focal epilepsy.

Objectives

Aim of our study was to determine the efficacy and safety of Eslicarbazepine Acetate, observe its well-tolerated use and monitor adverse effects in newly diagnosed patients of focal epilepsy.

Methods

Study was done at Department of Psychiatry, Teerthanker Mahaveer University, Moradabad. A total of 30 newly diagnosed cases of focal epilepsy between 18-60 years of age were studied for 6 months, using a Semi-structured Interview and Liverpool Adverse Events Profile.

Results

Majority of patients were males (58%), between 21-30 years. Patients with partial/focal seizures (63%) were more common than those of generalized seizures (37%). Majority of the participants had 1-2 episodes of focal seizures weekly(48%), while some had almost daily(32%). Majority were on Eslicarbazepine Acetate 800 mg in two divided doses daily (64%), while the others received 1200 mg in three divided doses(32%). The mean Liverpool Adverse Events Profile score initially was 28.34 ± 6.28 which significantly improved after 4 weeks treatment to 22.80 ± 4.35 (p < 0.05). The improvement in newly diagnosed focal seizures patients was significantly more than other patients (p < 0.05). No major side effects were observed.

Conclusions

Eslicarbazepine Acetate as a monotherapy is effective in treating focal epilepsy. Better results of this drug are found in newly diagnosed focal epilepsy patients.

Disclosure

No significant relationships.

Host Cxcr2-Dependent Regulation of Pancreatic Cancer Growth, Angiogenesis, and Metastasis

Pancreatic ductal adenocarcinoma (PDAC) manifests aggressive tumor growth and early metastasis. Crucial steps in tumor growth and metastasis are survival, angiogenesis, invasion, and immunosuppression. Our prior research showed that chemokine CXC- receptor-2 (CXCR2) is expressed on endothelial cells, innate immune cells, and fibroblasts, and regulates angiogenesis and immune responses. Here, we examined whether tumor angiogenesis, growth, and metastasis of CXCR2 ligands expressing PDAC cells are regulated in vivo by a host CXCR2-dependent mechanism. C57BL6 Cxcr2-/- mice were generated following crosses between Cxcr2-/+ female and Cxcr2-/- male. Cxcr2 ligands expressing Kirsten rat sarcoma (KRAS-PDAC) cells were orthotopically implanted in the pancreas of wild-type or Cxcr2-/- C57BL6 mice. No significant difference in PDAC tumor growth was observed. Host Cxcr2 loss led to an inhibition in microvessel density in PDAC tumors. Interestingly, an enhanced spontaneous and experimental liver metastasis was observed in Cxcr2-/- mice compared with wild-type mice. Increased metastasis in Cxcr2-/- mice was associated with an increase in extramedullary hematopoiesis and expansion of neutrophils and immature myeloid precursor cells in the spleen of tumor-bearing mice. These data suggest a dynamic role of host CXCR2 axis in regulating tumor immune suppression, tumor growth, and metastasis.

Dynamics of noise-induced wave-number selection in the stabilized Kuramoto-Sivashinsky equation

We revisit the question of wave-number selection in pattern-forming systems by studying the one-dimensional stabilized Kuramoto-Sivashinsky equation with additive noise. In earlier work, we found that a particular periodic state is more probable than all others at very long times, establishing the critical role of noise in the selection process. However, the detailed mechanism by which the noise picked out the selected wave number was not understood. Here, we address this issue by analyzing the noise-averaged time evolution of each unstable mode from the spatially homogeneous state, with and without noise. We find drastic differences between the nonlinear dynamics in the two cases. In particular, we find that noise opposes the growth of Eckhaus modes close to the critical wave number and boosts the growth of Eckhaus modes with wave numbers smaller than the critical wave number. We then hypothesize that the main factor responsible for this behavior is the excitation of long-wavelength (q→0) modes by the noise. This hypothesis is confirmed by extensive numerical simulations. We also examine the significance of the magnitude of the noise.

Ten-year fracture risk predicted by proximal femur Hounsfield units

Colon cancer screening occurs at younger ages than osteoporosis screening. Bone density measurements using virtual colonoscopy performed for colon cancer screening can provide an early warning sign of patients at potential risk for osteoporosis-related fractures. Earlier identification may improve treatment and potentially fracture prevention.

INTRODUCTION

Opportunistic osteoporosis screening with computed tomography colonography (CTC) offers an opportunity to capitalize on earlier colorectal cancer screening to identify patients at risk of future fractures. The purpose of this study is to evaluate 10-year fracture and specifically hip fracture risk based on Hounsfield units (HU) obtained from CTC.

METHODS

We identified all CTC scans between 2004 and 2007 of patients 40 years and older with 10 years minimum follow-up. Hounsfield units were measured within the proximal femur and fractures identified via worldwide military records. Patients were stratified into two cohorts based on the presence or lack of a fracture in the wrist, spine, hip, or proximal humerus. Hounsfield unit measurements were compared between groups using Student's t test and the HU threshold was calculated that best approximated an 80% sensitivity to optimally screen patients for fracture risk. The odds ratio, negative predictive value, 10-year incidence of fracture, and survival curves were calculated.

RESULTS

We identified 3711 patients with 183 fractures over 10 years. The HU threshold that corresponded with an 80% sensitivity to identify fractures was 112 HU. The negative predictive value (NPV) for overall fractures and hip fractures was over 97%. The 10-year fracture incidence was higher in patients below 112 HU compared to those above for both overall fractures (6.3% vs 1.7%) and hip fractures (2.7% vs 0.07%). The 112 HU threshold corresponds with an odds ratio for overall fracture and hip fractures of 2.5 (95% confidence interval (CI), 1.7-3.6) and 24.5 (95% CI, 3.3-175.5), respectively.

CONCLUSION

In the 10 years following CTC, patients who experienced a fracture had lower hip HU. Decreasing HU on CTC may be an early warning sign of fracture potential.

Breast Cancer Cell-Neutrophil Interactions Enhance Neutrophil Survival and Pro-Tumorigenic Activities

Breast cancer remains the most prevalent cancer in women with limited treatment options for patients suffering from therapy-resistance and metastatic disease. Neutrophils play an important role in breast cancer progression and metastasis. We examined the pro-tumorigenic nature of the breast cancer cell-neutrophil interactions and delineated the differences in neutrophil properties between the chemotherapy-resistant and the parent tumor microenvironment. Our data demonstrated that high neutrophil infiltration is associated with disease aggressiveness and therapy resistance. In the human breast cancer dataset, expression of neutrophil-related signature gene expression was higher in tumors from therapy-resistant patients than therapy-sensitive patients. We observed that breast cancer-derived factors significantly enhanced neutrophil survival, polarization, and pro-inflammatory cytokine expression. Breast cancer cell-derived supernatant treated neutrophils significantly expressed high levels of interleukin-1β (IL-1β), CC-chemokine ligand-2-4 (CCL2, CCL3, CCL4), inducible nitric oxide synthase (iNOS), and matrix metallopeptidase-9 (MMP9), and formed extracellular traps (NETs). Moreover, neutrophils showed increased secretion of MMP9 when cultured with the supernatant of chemotherapy-resistant Cl66-Doxorubicin (Cl66-Dox) and Cl66-Paclitaxel (Cl66-Pac) cells in comparison with the supernatant of Cl66-parent cells. Together, these data suggest an important role of breast cancer cell-neutrophil interactions in regulating pro-tumor characteristics in neutrophils and its modulation by therapy resistance.

Impact of school-based physical activity interventions in primary schools: measuring what matters

Background

A growing number of small studies suggest that school-based physical activity initiatives can help children achieve the recommended 60 minutes of physical activity per day. However, the heterogeneity of outcomes and measures used in small studies prevents pooling of results to demonstrate whether short-term health benefits are sustained. Qualitative studies suggest many benefits that are not represented by outcomes in trials to date. The aim of this study was to generate a list of outcomes that have been studied to develop a core outcome set (COS) acceptable to key stakeholders for future studies evaluating school-based physical activity initiatives.

Methods

We searched six databases (MEDLINE, EMBASE, PsycINFO, CINAHL, CENTRAL and Cochrane Database of Systematic Reviews) systematically for reviews of school-based physical activity interventions, and extracted relevant studies to identify the outcomes and measures used in each paper. A long list was generated from the literature and a previous workshop with stakeholders. This study is registered with COMET (#1322), and with PROSPERO (CRD42019146621).

Results

75/121 cited studies drawn from 53/2409 reviews met our inclusion criteria. We grouped 65 outcomes into 3 domains: (i) physical activity and health (ii) social and emotional health, and (iii) educational attainment. We will conduct two Delphi survey rounds with four stakeholder groups (health professionals, researchers, educators and parents) to rate the importance of each outcome. A core outcome set will be generated from a consensus process.

Conclusions

There is currently a large variation of outcomes and measures studied that precludes evidence synthesis of the impact of school-based physical activity interventions. Consensus methods are needed to focus research on the outcomes that matter the most to key stakeholders and to provide tools for future studies to assess long-term impact.

Key messages

Variations in outcomes studied precludes evidence synthesis of SBPA intervention impacts. A core outcome set is needed to ensure future SBPA interventions measure outcomes that matter the most.

Early years pathways to inequalities in childhood asthma? A causal mediation analysis

Background

Asthma affects one in five children in the United Kingdom (UK). Children in deprived areas have twice as many unplanned admissions for wheeze but mediating pathways between socioeconomic circumstances and asthma remain unclear. We aimed to quantify which early years pathways explain inequalities in childhood asthma in the UK.

Methods

We analysed data on 10650 children from the Millennium Cohort Study (MCS), a nationally representative sample of the UK population. Early life socioeconomic circumstance (SEC) was measured by maternal education at birth. Our outcome was parent-reported asthma at 5 years of age categorised as none, diagnosed asthma and diagnosed asthma with wheeze symptoms in the preceding year. Mediators were grouped into perinatal characteristics (maternal BMI, breastfeeding duration, birthweight, gestation, maternal smoking and alcohol use during pregnancy), neighbourhood features (pollution, grime and environment issues, traffic volume, housing quality) and the home environment (damp/condensation, tenure, pets, tobacco smoke). We used multinomial regression to examine the total effect of SEC on childhood asthma, then adjusted for all potential mediators. Using causal mediation analysis, we will estimate the proportion mediated by blocks of mediators and the natural indirect effect (NIE) via each block of mediators.

Results

Children whose mothers had no qualifications were more than twice as likely to have asthma by the age of 5 years with a wheeze episode in the preceding year compared with those whose mothers had degree-level qualifications (relative risk (RR) 2.21, 95% CI 1.44 to 3.40). After adjustment for all mediators, there was a 69% reduction to aRR 1.38 (95% CI 0.89 to 2.14).

Conclusions

Perinatal characteristics and early years neighbourhood features and measures of the home environment partially contribute to inequalities in childhood asthma.

Key messages

The antenatal period and early years of development are important for targeting interventions to reduce inequalities in asthma. About two-thirds of the social inequality in childhood asthma was explained by perinatal characteristics, early years neighbourhood features and the home environment.

Impact of financial incentives for primary care to give long acting reversible contraceptive advice

Background

Long acting reversible contraceptives (LARC) are cost-effective but uptake remains poor even in high income settings. In 2009/10, a pay-for-performance (P4P) scheme in the United Kingdom was introduced for primary care physicians to offer advice about LARC to women attending for contraceptive care. We examined the equity and impact of this scheme on LARC uptake and abortions

Methods

We examined records of women aged 13 to 54 years registered with a primary care practice in the UK Clinical Practice Research Datalink from 2004/05 to 2013/14. We used interrupted time series analysis to examine trends in annual LARC and non-LARC hormonal contraception (NLHC) uptake and abortion rates, stratified by age, region and deprivation groups, before and after P4P was introduced in 2009/10.

Results

LARC uptake among women of all ages increased immediately after P4P with step change of 5.36 per 1,000 women (95% CI 5.26 to 5.45). Largest increase was in women aged 20 to 24 years (8.40, 8.34 to 8.47). NLHC uptake fell in all women with a step change of -22.9 (-24.5 to -21.2). Among LARC methods, contraceptive injection and implant had the greatest increase after P4P; step changes were 1.68 (1.67 to 1.70) and 1.64 (1.63 to 1.65) respectively. Abortion rates fell across all 12 regions in UK and in all women immediately after P4P with a step change of -2.28 (-2.99 to -1.57). The largest falls occurred in women aged 13 to 19 years (step change -5.04, -7.56 to -2.51) and women from the most deprived group (step change -4.40, -6.89 to -1.91).

Conclusions

Pay-for-performance scheme for primary care physicians to give LARC advice to women attending for contraception was associated with desirable impact and equity of LARC prescriptions and abortion.

LARC uptake increased in women of all ages, especially 13-19 and 20-24 years. Abortion rates fell in all UK regions and age groups, particularly 13-19 and 20-24 years and those from deprived quintile.

Key messages

Pay-for-performance scheme for primary care practitioners to give LARC advice to women attending for contraception was associated with desirable impact and equity of LARC prescriptions and abortion. LARC uptake increased in women of all ages, especially 13-19 and 20-24 years. Abortion rates fell in all UK regions and age groups, particularly 13-19 and 20-24 years and those from deprived quintile.

Abstract 6194: Evaluation of the differential expression profile of CXC-receptor-2 ligands for potential biomarker candidates in pancreatic ductal adenocarcinoma

The major complexity of pancreatic cancer (PC) cases is late clinical presentation and metastasis at the time of detection. Achievement of significant clinical advancement in the treatment of PC disease needs extensive research efforts to discover early detection markers of this disease. In this study, we wanted to analyze the expression profile of different CXC-receptor 2 (CXCR2) ligands, well documented in the literature for their role in inflammation, in pancreatic ductal adenocarcinoma (PDAC) cases for the potential of biomarker candidates. With this perspective, we utilized different online portals to evaluate mRNA expression of different CXCR2 ligands CXCL1-3 and 5-8 in PDAC tumors in comparison with the normal pancreas. Analysis of GEO PDAC microarray dataset, GSE15471 containing 39 pancreatic tumors with corresponding matched normal samples, showed significantly higher expression of CXCL-3,5,6,8 in pancreatic tumors in comparison with their matched normal tissue. Similarly, analysis of next-generation sequenced transcriptomics data on MiPanda portal showed higher expression of CXCL-1,3,5,6,8 in pancreatic tumors of 417 PC patients in comparison with the normal pancreas. Interestingly, only CXCL5 ligand showed association with patient survival data based on the mRNA, miRNA, or lncRNA expression on Oncolnc-TCGA portal. PC patients with lower CXCL5 expression showed significantly higher survival in comparison with patients with higher CXCL5 expression. Next, we evaluated the expression pattern of CXCR2 ligands CXCL1, 3, and 8 in the human PC tissue specimens and using pancreatic tissues derived from disease progression mouse model of PDX-cre-LSL-KRASG12D. Immunohistochemical (IHC) analysis revealed positive staining for CXCL1, and 3 in both in the ducts and the stroma of the human PC tumors and normal pancreas specimens. However, in normal pancreas, the expression was localized only to the acinar cell compartment and pancreatic ducts were negative for expression. Overall the average composite score of CXCL3 IHC was higher in the PC tissue specimens versus the normal pancreas. Furthermore, we observed an increase in the expression of mCXCL1, 3, and 5 in the pre-cancerous lesions of tumors and metastasis derived from PDX-cre-LSL-KrasG12D. However, unlike the human tissues the normal murine pancreas was negative for the expression of mCXCL1 and 5. Lastly, mRNA expression analysis of nine different human PC cell lines showed higher CXCL2, 3, and 5 in cell lines derived from metastatic sites in comparison with cell lines derived from primary tumors. Our observations resonated with CXCL5 protein levels in these cell lines. In conclusion, our data suggest that among different CXCR2 ligands, CXCL5 shows the potential of being used as a biomarker in PC patients.

Citation Format: Sugandha Saxena, Abhilasha Purohit, Evie Ehrhorn, Pranita Atri, Caitlin Molczyk, Michelle Varney, Rakesh K. Singh. Evaluation of the differential expression profile of CXC-receptor-2 ligands for potential biomarker candidates in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6194.

Prevalence and duration of gastrointestinal symptoms before diagnosis of Inflammatory Bowel Disease and predictors of timely specialist review: a population-based study

BACKGROUND AND AIMS

Lack of timely referral and significant waits for specialist review amongst individuals with unresolved gastrointestinal (GI) symptoms can result in delayed diagnosis of Inflammatory Bowel Disease (IBD).

AIMS

To determine the frequency and duration of GI symptoms and predictors of timely specialist review before the diagnosis of both Crohn's Disease (CD) and ulcerative colitis (UC).

METHODS

Case-control study of IBD matched 1:4 for age and sex to controls without IBD using the Clinical Practice Research Datalink from 1998-2016.

RESULTS

We identified 19,555 cases of IBD, and 78,114 controls. 1 in 4 cases of IBD reported gastrointestinal symptoms to their primary care physician more than 6 months before receiving a diagnosis. There is a significant excess prevalence of GI symptoms in each of the 10 years before IBD diagnosis. GI symptoms were reported by 9.6% and 10.4% at 5 years before CD and UC diagnosis respectively compared to 5.8% of controls. Amongst patients later diagnosed with IBD, <50% received specialist review within 18 months from presenting with chronic GI symptoms. Patients with a previous diagnosis of irritable bowel syndrome or depression were less likely to receive timely specialist review (IBS: HR=0.77, 95%CI 0.60-0.99, depression: HR=0.77, 95%CI 0.60-0.98).

CONCLUSIONS

There is an excess of GI symptoms 5 years before diagnosis of IBD compared to the background population which are likely attributable to undiagnosed disease. Previous diagnoses of IBS and depression are associated with delays in specialist review. Enhanced pathways are needed to accelerate specialist referral and timely IBD diagnosis.

CXCR2 signaling promotes secretory cancer-associated fibroblasts in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most challenging malignancies. Desmoplasia and tumor-supporting inflammation are hallmarks of PDAC. The tumor microenvironment contributes significantly to tumor progression and spread. Cancer-associated fibroblasts (CAFs) facilitate therapy resistance and metastasis. Recent reports emphasized the concurrence of multiple subtypes of CAFs with diverse roles, fibrogenic, and secretory. C-X-C motif chemokine receptor 2 (CXCR2) is a chemokine receptor known for its role during inflammation and its adverse role in PDAC. Oncogenic Kras upregulates CXCR2 and its ligands and, thus, contribute to tumor proliferation and immunosuppression. CXCR2 deletion in a PDAC syngeneic mouse model produced increased fibrosis revealing a potential undescribed role of CXCR2 in CAFs. In this study, we demonstrate that the oncogenic Kras-CXCR2 axis regulates the CAFs function in PDAC and contributes to CAFs heterogeneity. We observed that oncogenic Kras and CXCR2 signaling alter CAFs, producing a secretory CAF phenotype with low fibrogenic features; and increased secretion of pro-tumor cytokines and CXCR2 ligands, utilizing the NF-κB activity. Finally, using syngeneic mouse models, we demonstrate that oncogenic Kras is associated with secretory CAFs and that CXCR2 inhibition promotes activation of fibrotic cells (myofibroblasts) and impact tumors in a mutation-dependent manner.

Neutrophils in the Tumor Microenvironment

Neutrophils are the first responders to inflammation, infection, and injury. As one of the most abundant leukocytes in the immune system, neutrophils play an essential role in cancer progression, through multiple mechanisms, including promoting angiogenesis, immunosuppression, and cancer metastasis. Recent studies demonstrating elevated neutrophil to lymphocyte ratios suggest neutrophil as a potential therapeutic target and biomarker for disease status in cancer. This chapter will discuss the phenotypic and functional changes in the neutrophil in the tumor microenvironment, the underlying mechanism(s) of neutrophil facilitated cancer metastasis, and clinical potential of neutrophils as a prognostic/diagnostic marker and therapeutic target.

IL-17-CXC Chemokine Receptor 2 Axis Facilitates Breast Cancer Progression by Up-Regulating Neutrophil Recruitment

Recent evidence suggests that interactions among proinflammatory cytokines, chemokines, and cancer cell-recruited neutrophils result in enhanced metastasis and chemotherapy resistance. Nonetheless, the detailed mechanism remains unclear. Our aim was to discover the role of IL-17, CXC chemokine receptor 2 (CXCR2) ligands, and cancer-associated neutrophils in chemotherapy resistance and metastasis in breast cancer. Mice were injected with Cl66 murine mammary tumor cells, Cl66 cells resistant to doxorubicin (Cl66-Dox), or Cl66 cells resistant to paclitaxel (Cl66-Pac). Higher levels of IL-17 receptor, CXCR2 chemokines, and CXCR2 were observed in tumors generated from Cl66-Dox and Cl66-Pac cells in comparison with tumors generated from Cl66 cells. Tumors generated from Cl66-Dox and Cl66-Pac cells had higher infiltration of neutrophils and T helper 17 cells. In comparison with primary tumor sites, there were increased levels of CXCR2, CXCR2 ligands, and IL-17 receptor within the metastatic lesions. Moreover, IL-17 increased the expression of CXCR2 ligands and cell proliferation of Cl66 cells. The supernatant of Cl66-Dox and Cl66-Pac cells enhanced neutrophil chemotaxis. In addition, IL-17-induced neutrophil chemotaxis was dependent on CXCR2 signaling. Collectively, these data demonstrate that the IL-17-CXCR2 axis facilitates the recruitment of neutrophils to the tumor sites, thus allowing them to play a cancer-promoting role in cancer progression.

Wave-number selection in pattern-forming systems

Wave-number selection in pattern-forming systems remains a long-standing puzzle in physics. Previous studies have shown that external noise is a possible mechanism for wave-number selection. We conduct an extensive numerical study of the noisy stabilized Kuramoto-Sivashinsky equation. We use a fast spectral method of integration, which enables us to investigate long-time behavior for large system sizes that could not be investigated by earlier work. We find that a state with a unique wave number has the highest probability of occurring at very long times. We also find that this state is independent of the strength of the noise and initial conditions, thus making a convincing case for the role of noise as a mechanism of state selection.

Abstract 1982: Sustained CXCR2 signaling promotes secretory phenotype in cancer-associated fibroblasts of pancreatic cancer via activation of NFkB

Pancreatic cancer (PC) is the fourth leading cause of cancer-related deaths in the US and remains one of the most challenging malignancies. Desmoplasia and tumor-supporting inflammation are hallmarks of PC. In addition to the autonomous aggressiveness feature of PC malignant cells, host tumor microenvironment contribute greatly to tumor progression and spread. Cancer-associated fibroblasts (CAFs), represent the major component of the tumor microenvironment in PC, are implicated in facilitating therapy resistance and metastasis. Recent reports emphasize the concurrence of multiple subtypes of CAFs that carry out different functions. CXCR2 is a chemokine receptor that is known for its role during inflammation by recruiting innate immune cells and the induction of angiogenesis. In PC, oncogenic Kras upregulates CXCR2 and its ligands (CXCL1-3 and 5-8), which are linked to inducing tumor proliferation and immunosuppression as well as induction of malignant cells stemness contributing to therapy resistance. Deletion of CXCR2 in a syngeneic mouse model (Cxcr2-/-) of PC increased the abundance of fibrosis revealing a potential undescribed role of CXCR2 in regulating CAFs. We hypothesize that CXCR2 regulates CAFs function in PC and contribute to CAFs heterogeneity. Co-culture of PC tumor cells in the conditioned media of CAFs and co-culturing CAFs in conditioned media of tumor cells revealed an oncogenic Kras-dependent interaction. CAFs enhanced the growth of PC cells with oncogenic Kras; whereas, conditioned media of the PC cells with oncogenic Kras has inhibited CAFs growth. Paracrine factors derived from tumor cells decreased the expression of the fibrotic CAFs-associated markers including αSMA and collagen I, and increased the expression of immunosuppressive cytokines and tumor-promoting chemokines including IL-4, IL-10, IL-13 and CXCL7. Utilizing recombinant CXCR2 chemokines and CXCR2 inhibitors, we confirmed the involvement of CXCR2 in this secretory phenotype. CXCL1 and CXCL8 exhibited a similar effect on CAFs by downregulating αSMA and upregulating IL-4, IL-13 and CXCL7. CXCR2 inhibitors reverted some of the observed effects. Examining downstream signaling pathways revealed that this effect is mediated through activation of NFκB. We further confirmed these findings in-vivo. Immunohistochemistry revealed higher αSMA expression in the tumors implanted in Cxcr2-/- compared to wildtype mice. Altogether, we demonstrate that sustained signaling through CXCR2 activates NFκB and induces a secretory phenotype of CAFs in PC that upregulates pro-tumor immunosuppression growth factors.

Citation Format: Mohammad Awaji, Michelle Varney, Abhilasha Purohit, Lingyun Wu, Sugandha Saxena, Sushil Kumar, Surinder K. Batra, Rakesh K. Singh. Sustained CXCR2 signaling promotes secretory phenotype in cancer-associated fibroblasts of pancreatic cancer via activation of NFkB [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1982.

Abstract 4554: IL-17-CXCR2 axis promotes breast cancer metastasis and therapy resistance through facilitating recruitment of neutrophils

Breast cancer is one of the most common cancer types that happens to global females. The major challenges for breast cancer include therapy resistance and metastasis. Various factors and cancer-related immune cells are involved in tumor chemotherapy resistance process, including pro-inflammatory cytokine, interleukin (IL) 17, CXCR2 ligands (pro-inflammatory chemokines) and neutrophils. They are the key players for promoting cancer progression, and numerous reports indicated them as a potential therapeutic target for various cancer types including breast cancer. However, the detailed mechanism(s) remains unclear. In the present study, we investigate the role of neutrophils in chemotherapy resistance and metastasis in breast cancer.

In our previous study, we have observed increased levels of CXCR2 ligands in chemotherapy-resistant cells comparing with Cl66 parent cells. In this study, we observed upregulated IL17, IL17 receptor (IL-17R), granulocyte colony stimulating factor (GCSF) by qRT- PCR in resistant cells compared with parent cells. We further evaluated the protein levels of CXCR2 and its ligands, IL17 and its receptor, frequencies of neutrophils and T-helper 17 (Th17) cells in primary and metastatic tumors through using immunohistochemistry method. There were higher levels of IL17R, CXCR2, and CXCR2 ligands in metastatic tumor sites in comparison to the primary tumor sites. Moreover, we observed increased levels of IL17R, CXCR2, CXCR2 ligands together with the higher frequencies of neutrophils and Th17 cells in resistant tumors than Cl66 tumors. At the same time, tumor cells treated with IL-17 increased its proliferation rate and its expression of CXCL1 & CXCL5; and the increase was all in a concentration-dependent manner. In addition, the increase of CXCR2 ligands by IL17 was inhibited when we treated the tumor cells with ERK and NF-KB signaling inhibitors, indicating both pathways are involved in the regulation of IL17-induced CXCR2 ligands secretion.

Together, our data demonstrate an IL17-CXCR2 ligands axis plays protumorigenic inflammation, facilitating therapy resistance and metastasis through recruited neutrophils.

Citation Format: Lingyun Wu, Sugandha Saxena, Mohammad Awaji, Bhawna Sharma, Rakesh Singh. IL-17-CXCR2 axis promotes breast cancer metastasis and therapy resistance through facilitating recruitment of neutrophils [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4554.

Abstract 1725: Mutationally activated KRAS(G12D) upregulates the expression of axonal guidance cue Semaphorin-5A in pancreatic cancer

Mutation of KRAS is commonly found in different human cancers and is generally responsible for driving tumorigenesis. Unfortunately, direct inhibitors of KRAS are not available. Thus, scientists are in search of alternative strategies that can repress the oncogenic properties of KRAS and can benefit a large number of cancer patients. Drugs targeting KRAS downstream effectors are under investigation but are facing numerous challenges in their clinical implementation. Accumulating evidence suggests that the genetic status of KRAS can modulate the role of axonal guidance cue family members in tumorigenesis. Previous reports from our laboratory have identified upregulation of one such molecule Semaphorin-5A (SEMA5A) in murine model based on KRAS gene mutation in pancreatic progenitor cells that bear a striking similarity to the human PDAC condition. We utilized PDX-cre-LSL-Kras(G12D) (KC) for studying Sema5A expression and observed no expression of Sema5A in the normal pancreas, derived from the control PDX-cre mice, however, we observed Sema5A expression in PDX-cre-LSL-Kras(G12D) mice beginning at ten weeks of age. Furthermore, we observed an increase in SEMA5A expression in the tumors of mice aged at twenty-five and fifty weeks, representing a fully developed PDAC condition. To investigate the relationship between KRAS status and SEMA5A, we assessed whether KRAS(G12D) alters the expression of SEMA5A using immortalized human pancreatic ductal cells having endogenous wild-type KRAS but an exogenous expression of KRAS(G12D) [HPNE-KRAS]. We detected higher expression of SEMA5A in the KRAS(G12D) bearing HPNE-KRAS cells in comparison with their control counterpart HPNE-Tert. Stable clones of CD18/HPAF cell line knocked-down for KRAS(G12D) demonstrated inhibition of SEMA5A expression in comparison with their respective Control CD18/HPAF cells bearing an endogenous expression of mutant KRAS. We also analyzed SEMA5A expression in the cells lines derived from the serial passage of COLO 357 cells through mice to achieve highly invasive/metastatic variants also leading to the selection of cells that express mutationally activated KRAS. L3.3 cells, with no point mutations in the KRAS gene, expressed lower SEMA5A in comparison with highly metastatic L3.6pl cells bearing a point mutation in codon 12, thereby encoding a mutationally activated KRAS(G12D). Together, our data suggest that KRAS(G12D) mutation directly upregulates the expression of axon guidance cue molecule-SEMA5A in the PDAC cells. Our findings open an avenue of molecules that can serve as secondary targets to repress KRAS activity in pancreatic cancer.

Citation Format: Sugandha Saxena, Babita Tomar, Lingyun Wu, Mohammad Awaji, Satyanarayan Rachagani, Michel J. Ouellette, Surinder K. Batra, Bhavana J. Dave, Rakesh K. Singh. Mutationally activated KRAS(G12D) upregulates the expression of axonal guidance cue Semaphorin-5A in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1725.

Abstract 2055: Differential expression of TP73 isoforms modulates cell survival and therapeutic response in diffuse large B-cell lymphoma

Rearrangements of the chromosome locus 1p36 with ensuing deletion or disruption of TP73, one of the most distally located putative tumor suppressor genes, is frequent in non-Hodgkin lymphoma (NHL) and confers inferior prognosis. TP73 shares homology to TP53 and is capable of transactivating p53 target genes. Earlier reports in normal B-cells and lymphoma animal models suggest an important role of p73 in B-cell lymphomas, however, the biological significance of p73 isoforms in Diffuse large B-cell lymphoma (DLBCL) is not clear. Diffuse large B-cell lymphoma is the most common form of NHL, and although long-term remission is achieved with current therapies, relapse occurs in almost one-third of the patients. Previously, we have demonstrated that the differential expression of p73 isoforms (TAp73 and ΔNp73) correlate with proliferation and apoptosis in DLBCL. In the present study, we examined whether modulating the expression of these p73 isoforms in DLBCL cells regulates cell survival, proliferation, and response to the chemotherapeutic agent, doxorubicin. We performed in vitro studies in DLBCL cells and modulated the expression of the two opposing p73 isoforms (TAp73 and ΔNp73) using expression vectors and siRNA in DHL16 (GCB subtype) and OCI-Ly3 (ABC subtype) cells. Under normal conditions TAp73-transfected cells showed comparable growth to control vector-transfected cells; however, the TAp73-transfected cells were more susceptible to serum deprivation as well as doxorubicin. In contrast, ΔNp73-transfected cells had accelerated growth when compared with control vector-transfected cells under normal conditions and were more resistant to serum deprivation and doxorubicin treatment. Subsequently, we analyzed the p73 direct transcriptional pro-apoptotic targets in cells transfected with TAp73 and ΔNp73 and vector control. Both the common p53 and p73 targets (PUMA and NOXA) as well as the exclusively p73 targetsGRAMD4 and BIM, were up-regulated in the TAp73-transfected cells compared to control cells. A reduction of PUMA, BIM, and GRAMD4 was observed in the ΔNp73-transfected cells as compared to control cells. Furthermore, we observed that p73 knockdown using p73 siRNA altered the growth and the response to doxorubicin in both DLBCL cell lines. Together, these data demonstrate the significant biological role of p73 isoforms in DLBCL pathogenesis and therapeutic response. Our findings illustrate that modulation of TP73 isoforms induces apoptosis and expression of pro-apoptotic targets, thus establishing p73 as a potential therapeutic target in DLBCL.

Citation Format: Hesham M. Hassan, Michelle L. Varney, Sugandha Saxena, Rakesh K. Singh, Bhavana J. Dave. Differential expression of TP73 isoforms modulates cell survival and therapeutic response in diffuse large B-cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2055.

Neuroinflammation is a putative target for the prevention and treatment of perioperative neurocognitive disorders

INTRODUCTION

The demographics of aging of the surgical population has increased the risk for perioperative neurocognitive disorders in which trauma-induced neuroinflammation plays a pivotal role.

SOURCES OF DATA

After determining the scope of the review, the authors used PubMed with select phrases encompassing the words in the scope. Both preclinical and clinical reports were considered.

AREAS OF AGREEMENT

Neuroinflammation is a sine qua non for development of perioperative neurocognitive disorders.

AREAS OF CONTROVERSY

What is the best method for ameliorating trauma-induced neuroinflammation while preserving inflammation-based wound healing.

GROWING POINTS

This review considers how to prepare for and manage the vulnerable elderly surgical patient through the entire spectrum, from preoperative assessment to postoperative period.

AREAS TIMELY FOR DEVELOPING RESEARCH

What are the most effective and safest interventions for preventing and/or reversing Perioperative Neurocognitive Disorders.

CXCR1/2 Chemokine Network Regulates Melanoma Resistance to Chemotherapies Mediated by NF-κB

BACKGROUND

Cancer-related inflammation is recognized as a driver for tumor progression and chemokines are important players in both inflammation and the progression of many cancer types. CXC chemokines, especially CXCL8, have been implicated in melanoma growth and metastasis, while less is known for their roles in drug resistance.

METHODS

We generated drug-resistant cells by continuous exposure to chemotherapeutic drugs and analyzed the mechanism(s) of therapy resistance in malignant melanoma.

RESULTS

We report chemotherapies induced upregulation of a variety of chemokines in the CXCR1/CXCR2 network by an NF-κB-dependent mechanism. Notably, analysis of the drug-resistant melanoma cell line selected after prolonged exposure to chemotherapeutic drug dacarbazine revealed higher levels of CXCL8 and CXCR2 compared with parent cells as a signature of drug resistance. CXCR2 neutralization markedly improved sensitivity to dacarbazine in melanoma cells.

CONCLUSION

These data provide insights into what drives melanoma cells to survive after chemotherapy treatment, thus pointing to strategies for developing combined drug therapies for combating the problem of chemotherapy resistance in melanoma.

Ophthalmological manifestation in patients of tuberculous meningitis

BACKGROUND

Vision impairment, blindness in particular is a devastating complication in patients with tuberculous meningitis. However, information regarding ophthalmological manifestation and its impact on vision is sparse in the literature. This study evaluated the spectrum of ophthalmological manifestations in tuberculous meningitis, including retinal nerve fiber layer thickness assessment by optic coherence tomography and its correlation with visual and clinical outcome.

METHODS

This was a prospective observational study done from October 2015 to March 2017. Consecutive patients of tuberculous meningitis, diagnosed as per consensus case definition were included in the study. The patients were divided into two categories: uncomplicated and complicated tuberculous meningitis. Clinical evaluation, cerebrospinal fluid examination and contrast enhanced MRI of brain was done. Detailed ophthalmological evaluation including optic coherence tomography was done in all patients. All the patients were followed for 6 months. The primary outcome was blindness or low vision after 6 months. The secondary outcome was death or severe disability after 6 months. It was defined as modified Barthel index (MBI) ≤ 12 at 6 months (including disability plus death). Appropriate statistical analysis was done.

RESULTS

Out of 101 patients of tuberculous meningitis, 47 patients of TBM belonged to uncomplicated category, while 54 patients were of complicated group. The visual impairment was present in 24 out of 101 (23.76%) patients out of which 20 (19.8%) patients had low vision while 4 (3.96%) had blindness. The visual impairment was more evident in complicated group, low vision 0.03 (1.2-31.5). The most common abnormality on fundus examination was papilledema (22.8%). The complicated group had more incidence <0.0001 (19.6-48). Optic atrophy was found in three patients while choroid tubercles were found in eight patients (all complicated TBM group). RNFL thinning was noted in 10 patients in both the eyes. On univariate analysis, presence of diplopia at baseline, impairment of color vision at baseline, visual impairment at baseline, cranial nerve VIth involvement, optic atrophy and papilledema at baseline, RNFL thinning, abnormal VEP and baseline MBI were associated with poor visual outcome. On multivariate analysis, none of the factors were found to be independently associated with poor visual outcome. On univariate analysis, many factors including baseline MRC staging, altered sensorium, seizure, hemiparesis, basal exudates, infarcts, optochiasmaticarachnoiditis, visual impairment at baseline were found to be associated with poor clinical outcome at 6 months. On multivariate analysis, presence of seizure (P = 0.047, odds ratio = 78.59, 95% confidence interval (1.07-578.72)) was the only factor found to be independently associated with poor outcome.

CONCLUSION

Wide spectrum of ophthalmological manifestation was observed in patients of tuberculous meningitis. The visual impairment was more evident in complicated tuberculous meningitis. Ophthalmological findings like optic atrophy, papilledema and RNFL thinning were associated with poor visual outcome on univariate but not multivariate analysis. Visual impairment at baseline, among other factors was associated with poor clinical outcome on univariate analysis, whereas seizure was the only factor independently associated with poor outcome on multivariate analysis.

CXCR2: A Novel Mediator of Mammary Tumor Bone Metastasis

Most breast cancer patients die due to bone metastasis. Although metastasis accounts for 5% of the breast cancer cases, it is responsible for most of the deaths. Sometimes even before the detection of a primary tumor, most of the patients have bone and lymph node metastasis. Moreover, at the time of death, breast cancer patients have the bulk of the tumor burden in their bones. Therapy options are available for the treatment of primary tumors, but there are minimal options for treating breast cancer patients who have bone metastasis. C-X-C motif chemokine receptor type 2 (CXCR2) receptor-mediated signaling has been shown to play a critical role during bone-related inflammations and its ligands C-X-C motif chemokine ligand 6 (CXCL6) and 8 (CXCL8) aid in the resorption of bone during bone metastasis. In this study, we tested the hypothesis that CXCR2 contributes to mammary tumor-induced osteolysis and bone metastasis. In the present study, we examined the role of both tumor cell-derived and host-derived CXCR2 in influencing mammary tumor cell bone metastasis. For understanding the role of tumor cell-derived CXCR2, we utilized Cl66 CXCR2 knockdown (Cl66-shCXCR2) and Cl66-Control cells (Cl66-Control) and observed a significant decrease in tumor growth and tumor-induced osteolysis in Cl66-shCXCR2 cells in comparison with the Cl66-Control cells. Next, for understanding the role of host-derived CXCR2, we utilized mice with genomic knockdown of CXCR2 (Cxcr2^-/-) and injected Cl66-Luciferase (Cl66-Luc) or 4T1-Luciferase (4T1-Luc) cells. We observed decreased bone destruction and metastasis in the bone of Cxcr2^-/- mice. Our data suggest the importance of both tumor cell- and host-derived CXCR2 signaling in the bone metastasis of breast cancer cells.

Semaphorin-5A maintains epithelial phenotype of malignant pancreatic cancer cells

BACKGROUND

Pancreatic cancer (PC) is a highly aggressive disease, and the lethality of this disease stems from early metastatic dissemination where surgical removal cannot provide a cure. Improvement of the therapeutic outcome and overall survival of PC patients requires to understand the fundamental processes that lead to metastasis such as the gain of cellular migration ability. One such family of proteins, which are essential players of cellular migration, is Semaphorin. Previously, we have identified one of the Semaphorin family member, Semaphorin-5A (SEMA5A) to be involved in organ-specific homing during PC metastasis. We have also demonstrated that SEMA5A has a constitutive expression in PC cell lines derived from metastatic sites in comparison with low endogenous expression in the primary tumor-derived cell line. In this study, we examined whether constitutive SEMA5A expression in metastatic PC cells regulates tumor growth and metastatic potential.

METHODS

We generated SEMA5A knockdown in T3M-4 and CD18/HPAF cells and assessed their phenotypes on in vitro motility, tumor growth, and metastatic progression.

RESULTS

In contrary to our initial expectations, orthotopic injection of SEMA5A knockdown cells into nude mice resulted in a significant increase in both tumor burden and liver metastases in comparison with the Control cells. Similarly, we observed higher in vitro migratory potential with pronounced morphological changes associated with epithelial-mesenchymal transition (EMT), a decrease in the expression of epithelial marker E-cadherin (E-Cad), increase in the expression of mesenchymal markers N-cadherin (N-Cad) and Snail and the activation of the Wnt-signaling pathway in SEMA5A knockdown cells. Furthermore, re-establishing SEMA5A expression with a knockdown resistant mouse Sema5A in SEMA5A knockdown cells resulted in a reversion to the epithelial state (mesenchymal-epithelial transition; MET), as indicated by the rescue of E-Cad expression and a decrease in N-Cad and Snail expression.

CONCLUSIONS

Collectively, our data suggest that SEMA5A expression maintains epithelial phenotype in the metastatic microenvironment.

Gibberellin-induced perturbation of source-sink communication promotes sucrose accumulation in sugarcane

Constant removal of sugars from the site of synthesis (i.e., leaves), in response to elevated sink (culm) demand, may perhaps prevent damping of photosynthesis, by sugar, and hence promote further sucrose accumulation in the culm. In this study, gibberellic acid (GA₃) induced nearly 42.3% enlargement in cell size and about 39.3% increase in internodal length (sink capacity), 177% escalation in reducing sugar level (sink strength), amplified the expression of sucrose-metabolizing enzymes (sink demand), viz., 7.5-fold for SAI, 4.5-fold for CWI, sixfold for SPS, all demonstrating facilitation of augmented sucrose accumulation in the culm. The GA₃-treated BO 91 cane (late maturing sugarcane variety) exhibited an elevated final sucrose concentration (40.54-41.6%) as compared to control (30.44-38.8%). The GA₃-sprayed cane of early maturing Co J64 also showed such a boost, but it was lost by the end of maturity, perhaps due to inversion and/or the less effective GA₃ treatment. Thus, results demonstrated the role of GA₃ in augmenting sucrose content of cane culm, possibly by influencing source-sink dynamics in sugarcane.