PIKfyve controls dendritic cell function and tumor immunity

The modern armamentarium for cancer treatment includes immunotherapy and targeted therapy, such as protein kinase inhibitors. However, the mechanisms that allow cancer-targeting drugs to effectively mobilize dendritic cells (DCs) and affect immunotherapy are poorly understood. Here, we report that among shared gene targets of clinically relevant protein kinase inhibitors, high PIKFYVE expression was least predictive of complete response in patients who received immune checkpoint blockade (ICB). In immune cells, high PIKFYVE expression in DCs was associated with worse response to ICB. Genetic and pharmacological studies demonstrated that PIKfyve ablation enhanced DC function via selectively altering the alternate/non-canonical NF-κB pathway. Both loss of Pikfyve in DCs and treatment with apilimod, a potent and specific PIKfyve inhibitor, restrained tumor growth, enhanced DC-dependent T cell immunity, and potentiated ICB efficacy in tumor-bearing mouse models. Furthermore, the combination of a vaccine adjuvant and apilimod reduced tumor progression in vivo. Thus, PIKfyve negatively controls DCs, and PIKfyve inhibition has promise for cancer immunotherapy and vaccine treatment strategies.

Targeting the lipid kinase PIKfyve upregulates surface expression of MHC class I to augment cancer immunotherapy

Despite the remarkable clinical success of immunotherapies in a subset of cancer patients, many fail to respond to treatment and exhibit resistance. Here, we found that genetic or pharmacologic inhibition of the lipid kinase PIKfyve, a regulator of autophagic flux and lysosomal biogenesis, upregulated surface expression of major histocompatibility complex class I (MHC-I) in cancer cells via impairing autophagic flux, resulting in enhanced cancer cell killing mediated by CD8+ T cells. Genetic depletion or pharmacologic inhibition of PIKfyve elevated tumor-specific MHC-I surface expression, increased intratumoral functional CD8+ T cells, and slowed tumor progression in multiple syngeneic mouse models. Importantly, enhanced antitumor responses by Pikfyve-depletion were CD8+ T cell- and MHC-I-dependent, as CD8+ T cell depletion or B2m knockout rescued tumor growth. Furthermore, PIKfyve inhibition improved response to immune checkpoint blockade (ICB), adoptive cell therapy, and a therapeutic vaccine. High expression of PIKFYVE was also predictive of poor response to ICB and prognostic of poor survival in ICB-treated cohorts. Collectively, our findings show that targeting PIKfyve enhances immunotherapies by elevating surface expression of MHC-I in cancer cells, and PIKfyve inhibitors have potential as agents to increase immunotherapy response in cancer patients.

A Rare Case of Localized Hypertrichosis in Conjunction with Erythema Nodosum

Acquired hypertrichosis can occur in local inflammation. Erythema nodosum (EN) is a hypersensitivity reaction to various underlying antigenic stimuli including Mycobacterium tuberculosis, which causes inflammation in the septa of subcutaneous fat. There were several case reports that describe the association of localized hypertrichosis (LH) with traumatic panniculitis and lupus panniculitis. To our knowledge, this is the first reported case of acquired LH associated with EN. Thus, EN can be added to the list of causes of localized hypertrichosis.

Intersection of immune and oncometabolic pathways drives cancer hyperprogression during immunotherapy

Immune checkpoint blockade (ICB) can produce durable responses against cancer. We and others have found that a subset of patients experiences paradoxical rapid cancer progression during immunotherapy. It is poorly understood how tumors can accelerate their progression during ICB. In some preclinical models, ICB causes hyperprogressive disease (HPD). While immune exclusion drives resistance to ICB, counterintuitively, patients with HPD and complete response (CR) following ICB manifest comparable levels of tumor-infiltrating CD8+ T cells and interferon γ (IFNγ) gene signature. Interestingly, patients with HPD but not CR exhibit elevated tumoral fibroblast growth factor 2 (FGF2) and β-catenin signaling. In animal models, T cell-derived IFNγ promotes tumor FGF2 signaling, thereby suppressing PKM2 activity and decreasing NAD+, resulting in reduction of SIRT1-mediated β-catenin deacetylation and enhanced β-catenin acetylation, consequently reprograming tumor stemness. Targeting the IFNγ-PKM2-β-catenin axis prevents HPD in preclinical models. Thus, the crosstalk of core immunogenic, metabolic, and oncogenic pathways via the IFNγ-PKM2-β-catenin cascade underlies ICB-associated HPD.

Clinical characteristics of chronic rhinitis following stroke

Background

We previously observed that patients with stroke complained of rhinitis symptoms that developed following the occurrence of stroke.

Objectives

To investigate the relationship between chronic rhinitis (CR) and stroke.

Methods

This retrospective study analyzed the medical records and questionnaires of patients with stroke who visited our outpatient clinic from June to December 2020. Stroke lesions were mainly classified as supratentorial, infratentorial, and supra/infratentorial lesions. Supratentorial lesions were further divided into cortex, subcortex, and mixed. Participants were screened for CR and were subsequently divided into the CR and non-CR groups. The Sino-Nasal Outcome Test questionnaire and a questionnaire on autonomic nervous system symptoms were administered to all patients.

Results

Clinically evaluated indicators were not significantly different between the two groups. The number of patients with lesions in both the cortex and subcortex was significantly higher in the CR group than in the non-CR group. The risk of CR was higher in male patients with stroke than their female counterparts; additionally, the risk of CR was higher in patients with stroke who had both cortical and subcortical lesions, as well as autonomic dysfunction.

Conclusions

Individuals with subcortical stroke damage had a greater probability of developing CR. The risk was increased in men, as compared with that in women, when autonomic symptoms were present.

Relation of Flatfoot Severity with Flexibility and Isometric Strength of the Foot and Trunk Extensors in Children

BACKGROUND

Flatfoot is a deformity in which the foot is flattened due to a decrease in or loss of the medial longitudinal arch.

STATEMENT OF THE PROBLEM

Few studies have investigated the relationship between the severity of flat feet, trunk strength, and joint flexibility.

PURPOSE

The aim of this study is to investigate the relationship between the severity of flatfoot and joint flexibility and foot and trunk strength in children with flexible flatfoot.

METHODS

This study included 16 children (boys, 12; girls, 4; age, 4~8 years) with flexible flatfeet. We examined the resting calcaneal stance position angle (RCSPA) and foot posture index (FPI) scores for clinical severity and radiographic parameters, such as calcaneal pitch angle, talometatarsal angle (TMA), and talocalcaneal angle (TCA). Muscle thicknesses of the tibialis posterior (TP), peroneus longus (PL), and L1 multifidus were measured by sonography. Isometric contraction of ankle inversion, eversion in a seating position, and lumbar extension at a prone position were induced using a handheld dynamometer to measure the maximum muscle strength for each muscle. Beighton's scoring system was used to assess joint flexibility by evaluating the hyperextension of the joint for each category when performing stretching motion. Spearman's rank correlation coefficient for nonparametric data was used.

RESULTS

The FPI showed a moderately negative correlation with the muscle thickness of TP (r = -0.558, p = 0.009) and L1 multifidus (r = -0.527, p = 0.012), and the strength of the ankle inverter (r = -0.580 p = 0.005) and lumbar extensor (r = -0.436 p = 0.043). RCSPA showed a moderately positive correlation with TCA (r = 0.510, p = 0.006). Beighton's score showed no significant correlation with all parameters.

CONCLUSION

In children with flatfoot, FPI reflected the clinical severity; thus, the more severe the symptoms, the weaker the ankle inverter and lumbar extensor.

Reliability of electroencephalogram indicator and event related potential in subacute stroke

Cognitive impairment is observed in 12% to 56% of stroke patients, and screening for cognitive impairment is often complex and time-consuming, with results dependent on patient compliance. Therefore, there is a need for an objective method to assess cognitive impairment regardless of patient compliance. Objective evaluation methods include electroencephalogram (EEG) and event-related potential (ERP). This study was conducted to assess intra-tester reliability of resting EEG-based spectral features and auditory/visual P300 latency/amplitude in patients with subacute ischemic stroke. Twenty patients with subacute ischemic stroke were included in the study. The resting EEG and P300 wave using an auditory and visual oddball paradigm were measured at baseline and once again in 24 hours. The following electrode positions (10-20 system) were constantly recorded: F3 (Frontal), Fz, F4, C3 (Central), Cz, C4, P3 (Parietal), Pz, P4. DAR (delta/alpha ratio) and BSI (brain symmetry index) were determined using EEG data. F3 and F4, C3 and C4 and P3 and P4 were switched according to the stroke side and classified as affected hemisphere (AH) and unaffected hemisphere (UH) after the evaluation. In ERP, the amplitude and latency of P300 were obtained. In reliability analysis of EEG-based spectral characteristics, significant reliability was observed for DAR (ICC = 0.447), BSldir (ICC = 0.713) and BSIdirtheta (ICC = 0.724) (Table 4). DAR was showed a poor ICC level, and BSIdir and BSIdirtheta had a moderate ICC level. Visual P300 latency showed excellent intraclass correlation coefficient (ICC) in several montages (PUH = 0.972, Pz = 0.945). In 6 montages, auditory P300 latency was reliable, while in 9 montages, visual P300 latency was reliable. In 4 montages, auditory P300 amplitude was reliable, while visual P300 amplitude was reliable in 7. The visual P300 was more reliable than the auditory P300. The ICC values for P300 latency were greater than those for amplitude. Therefore, when ERP is performed on subacute stroke patients, visual has higher reliability than auditory.

Distribution Analysis of Candida albicans according to Sex and Age in Clinical Specimen Testing for Sexually Transmitted Diseases

The prevalence of candidiasis, a contagious disease with high morbidity and mortality, has sharply increased globally over the last two decades. Candida albicans can cause serious infections in patients with weak immunity and in recipients of prolonged antibiotic treatment. Consequently, rapid and accurate identification of species can play an important role in the treatment of candidiasis. Here, we investigated the positive rate and infection trend of Candida albicans according to age, specimen type, and sex using multiplex real-time polymerase chain reactionbased testing of samples collected for the diagnosis of sexually transmitted diseases in Korea between 2018 and 2020. When the type of specimen collected was a swab, the positive rate of Candida albicans was higher among younger women, and tended to decrease with age. Analysis of swab samples revealed higher positive rates than urinalysis. The reduction trend in positive rates by age was comparable between the overall samples and urine specimens. Among male patients, the positive rate did not differ substantially across the various types of specimens collected. Previous studies have shown a higher prevalence of non-albicans Candida species than Candida albicans in clinical specimens, and exclusion of the former from our analysis may be a limitation of this study. However, our findings contribute significantly to the literature because globally, there is a paucity of epidemiological studies using molecular techniques to detect Candida albicans in sexually transmitted disease test samples.

Abstract 2018: Therapeutic benefit of dual ALK and FAK inhibition in neuroblastoma

Neuroblastoma (NB) is the most common extracranial pediatric tumor, and accounts for approximately 12% of cancer-related deaths in children. Though several genomic drivers have been identified, the development of targeted therapy for treating this aggressive pediatric malignancy has yet to be realized. Thus, there exists an urgent need to develop alternative therapeutic strategies for treating aggressive and metastatic NB. One novel approach is to therapeutically target anaplastic lymphoma kinase (ALK) and focal adhesion kinase (FAK), which are multi-functional tyrosine kinases implicated in neural development and play an important role in growth and metastasis of several cancers. Genomic aberrations of ALK such as overexpression, amplifications, and mutations, have been reported in NB. The role of FAK has also been delineated in NB as well as associated with disease metastasis. Using in silico analysis of sequencing data from NB patients procured from Pediatric MI-ONCOSEQ (precision oncology program), we found a cohort of patients that express high ALK and FAK expression. Given the potential roles of ALK and FAK in NB, we evaluated the efficacy of a novel compound ESK440, which is a dual ALK and FAK inhibitor. ESK440 has passed Phase 1 clinical trials in adult patients with solid tumors. It is capable of crossing the blood brain barrier and binds to several mutated forms of ALK, thus making ESK440 an attractive therapeutic candidate for treating NB. A wide panel of NB cancer cell lines were screened with ESK440, and a CellTiter-Glo® Luminescent Cell Viability Assay was used to determine the IC-50s. Our results revealed that NB cells with ALK genomic aberrations (mutations and amplifications) showed low IC-50 values. Further, treatment with ESK440 inhibited ALK and FAK associated signaling pathways. We also observed decreased expression of MYCN. Intriguingly, ESK440 studies in NB xenograft model (NB-1) resulted in tumor regression in treated animals. Altogether, our study has discovered the therapeutic potential of dual ALK and FAK inhibitor in NB, and our findings may provide the foundation for initiating clinical trials targeting this disease in pediatric patients.

Citation Format: Seema Chugh, Jean C. Tien, Jennifer Hon, Pushpinder Singh Bawa, Carson Kenum, Chi Chiang Li, Yunhui Cheng, Andrew D. Delekta, Jae Eun Choi, Rahul Mannan, Yuanyuan Qiao, Rajen Mody, Arul Chinnaiyan. Therapeutic benefit of dual ALK and FAK inhibition in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2018.

Viral Status Predicts the Patterns of Genome Methylation and Decitabine Response in Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma that is classified as Merkel cell polyomavirus-positive (virus positive [VP]) or Merkel cell polyomavirus-negative (virus negative [VN]). Epigenetic changes, such as DNA methylation, can alter gene expression and influence cancer progression. However, patterns of DNA methylation and the therapeutic efficacy of hypomethylating agents have not been fully explored in MCC. We characterized genome-wide DNA methylation in 16 MCC cell lines from both molecular subclasses in comparison with other cancer types and found that the overall profile of MCC is similar to that of small-cell lung carcinoma. Comparison of VP MCC with VN MCC revealed 2,260 differentially methylated positions. The hypomethylating agent decitabine upregulated the expression of antigen-presenting machinery in MCC cell lines and stimulated membrane expression of HLA-A in VP and VN MCC xenograft tumors. Decitabine also induced prominent caspase- and large T antigen‒independent cell death in VP MCC, whereas VN MCC cell lines displayed decreased proliferation without increased cell death. In mouse xenografts, decitabine significantly decreased the size of VP tumors but not that of VN tumors. Our findings indicate that viral status predicts genomic methylation patterns in MCC and that decitabine may be therapeutically effective against MCC through antiproliferative effects, cell death, and increased immune recognition.

Age and sex trends of Gardnerella vaginalis infection in patients with sexually transmitted infections in Korea

Background and Objectives: Gardnerella vaginalis and Candida albicans are the most common causative agents of bac- terial vaginosis, and infections with these pathogens lead to inflammation, endometritis, and pruritus. The aim of this retro- spective study was to determine the trends of G. vaginalis infections based on real-time PCR data according to age and sex in patients with sexually transmitted diseases. Materials and Methods: A total of 59,381 specimens isolated at a clinical laboratory from September 2018 to December 2020 were subjected to real-time PCR for the detection of G. vaginalis DNA. Sample types included catheter, pus, tissue, swab, and urine samples. Results: Among 59,381 samples, 20,718 (34.8%) were positive for G. vaginalis. Of the positive samples, 13,186 (63.7%) were from male patients and 7,532 (36.3%) were from female patients. Average patient age was 39.1 years (the average age of male and female patients was 38.34 and 40.43 years, respectively). Female patients younger than 19 years exhibited the highest incidence of G. vaginalis, at 71.57%, followed by 68.46% incidence in those aged 20-29 years; the lowest incidence was in women aged 40-49 years. Further, among specimen types, the highest number of G. vaginalis-positive specimens was obtained by the swab sampling method. Conclusion: From 2018 to 2020 in Korea, the number of tests conducted for bacterial vaginosis has increased, while the incidence of G. vaginalis infections appears to have decreased. the finding that female adolescents have a high tendency to carry the pathogen is important. and for effective surveillance of BV, sampling by cotton swabs and detection by multiplex PCR might be a good approach.

Autophagy Inhibition by Targeting PIKfyve Potentiates Response to Immune Checkpoint Blockade in Prostate Cancer

Multi-tyrosine kinase inhibitors (MTKIs) have thus far had limited success in the treatment of castration-resistant prostate cancer (CRPC). Here, we report a phase I-cleared orally bioavailable MTKI, ESK981, with a novel autophagy inhibitory property that decreased tumor growth in diverse preclinical models of CRPC. The anti-tumor activity of ESK981 was maximized in immunocompetent tumor environments where it upregulated CXCL10 expression through the interferon gamma pathway and promoted functional T cell infiltration, which resulted in enhanced therapeutic response to immune checkpoint blockade. Mechanistically, we identify the lipid kinase PIKfyve as the direct target of ESK981. PIKfyve-knockdown recapitulated ESK981's anti-tumor activity and enhanced the therapeutic benefit of immune checkpoint blockade. Our study reveals that targeting PIKfyve via ESK981 turns tumors from cold into hot through inhibition of autophagy, which may prime the tumor immune microenvironment in advanced prostate cancer patients and be an effective treatment strategy alone or in combination with immunotherapies.

Hormesis effects of gamma radiation on growth of quinoa (Chenopodium quinoa)

PURPOSE

Quinoa is an annual plant that grows well in high altitude regions with high radiation and ultraviolet intensity. It has known that high-dose radiation damages living organisms, but low-dose radiation also has a beneficial effect. Therefore, the purpose of this study is to investigate the hormesis effect of gamma-ray on quinoa by growth analysis and hyperspectral imaging.

MATERIALS AND METHODS

Quinoa seeds were irradiated at 50, 100, and 200 Gy emitted by ⁶⁰CO. Subsequently, the seeds were germinated and transplanted into pots, then conducted growth analysis and physiological evaluation every week, and hyperspectral imaging. Photosynthetic ability was measured at 35 days after transplanting (DAT), and the plants for each dose were divided into aerial and underground parts for biomass evaluation at 91 DAT. Various vegetation indices were estimated from 14 to 35 DAT by hyperspectral analysis, and the specific bands were extracted based on the PLS model using plant height, SPAD value, and chlorophyll fluorescence parameters.

RESULTS

We found that plant height and biomass were increased in quinoa plants treated with a low dose (50 Gy) as compared to control. Chlorophyll content and chlorophyll fluorescence were not different between doses at the early growth stage, but as growth progressed, the plant irradiated at 200 Gy began to be lower. The photosynthetic ability of the quinoa plant treated at 50 Gy was greater than other plants at 35 DAT. The vegetation indices related to the pigment status also were higher in the plants treated by irradiation at 50 Gy than the plants grown in other doses treatment units at the beginning of the growth. Using the PLS model we collected sensitive band wavelengths from hyperspectral image analysis. Among the collected bands, eight bands closely related to plant height, nine bands to chlorophyll content, and ten bands to chlorophyll fluorescence were identified.

CONCLUSION

Our results showed that the growth and physiological parameters of quinoa treated by low dose gamma irradiation to seeds were greater than that of control as well as the plant with higher doses. These findings confirm that the positive changes in the characteristics of quinoa with low dose radiation indicated that hormesis occurs at 50 Gy radiation.

Stanniocalcin 1 is a phagocytosis checkpoint driving tumor immune resistance

Immunotherapy induces durable clinical responses in a fraction of patients with cancer. However, therapeutic resistance poses a major challenge to current immunotherapies. Here, we identify that expression of tumor stanniocalcin 1 (STC1) correlates with immunotherapy efficacy and is negatively associated with patient survival across diverse cancer types. Gain- and loss-of-function experiments demonstrate that tumor STC1 supports tumor progression and enables tumor resistance to checkpoint blockade in murine tumor models. Mechanistically, tumor STC1 interacts with calreticulin (CRT), an "eat-me" signal, and minimizes CRT membrane exposure, thereby abrogating membrane CRT-directed phagocytosis by antigen-presenting cells (APCs), including macrophages and dendritic cells. Consequently, this impairs APC capacity of antigen presentation and T cell activation. Thus, tumor STC1 inhibits APC phagocytosis and contributes to tumor immune evasion and immunotherapy resistance. We suggest that STC1 is a previously unappreciated phagocytosis checkpoint and targeting STC1 and its interaction with CRT may sensitize to cancer immunotherapy.

Virus-positive Merkel Cell Carcinoma Is an Independent Prognostic Group with Distinct Predictive Biomarkers

PURPOSE

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma that can be divided into two classes: virus-positive (VP) MCC, associated with oncogenic Merkel cell polyomavirus (MCPyV); and virus-negative (VN) MCC, associated with photodamage.

EXPERIMENTAL DESIGN

We classified 346 MCC tumors from 300 patients for MCPyV using a combination of IHC, ISH, and qPCR assays. In a subset of tumors, we profiled mutation status and expression of cancer-relevant genes. MCPyV and molecular profiling results were correlated with disease-specific outcomes. Potential prognostic biomarkers were further validated by IHC.

RESULTS

A total of 177 tumors were classified as VP-MCC, 151 tumors were VN-MCC, and 17 tumors were indeterminate. MCPyV positivity in primary tumors was associated with longer disease-specific and recurrence-free survival in univariate analysis, and in multivariate analysis incorporating age, sex, immune status, and stage at presentation. Prioritized oncogene or tumor suppressor mutations were frequent in VN-MCC but rare in VP-MCC. TP53 mutation developed with recurrence in one VP-MCC case. Importantly, for the first time we find that VP-MCC and VN-MCC display distinct sets of prognostic molecular biomarkers. For VP-MCC, shorter survival was associated with decreased expression of immune markers including granzyme and IDO1. For VN-MCC, shorter survival correlated with high expression of several genes including UBE2C.

CONCLUSIONS

MCPyV status is an independent prognostic factor for MCC. Features of the tumor genome, transcriptome, and microenvironment may modify prognosis in a manner specific to viral status. MCPyV status has clinicopathologic significance and allows for identification of additional prognostic subgroups.

Erythema induratum of Bazin in a 10-year-old boy

Erythema induratum of Bazin (EIB) is a form of tuberculid resulting from hypersensitivity to tuberculosis antigen. EIB occurs most commonly in middle-aged women and is not typically seen in children. Here, we present a rare case of EIB, presenting as a chronic nodular panniculitis, in a 10-year-old Korean boy.

Merkel Cell Polyomavirus in Merkel Cell Carcinoma: Integration Sites and Involvement of the KMT2D Tumor Suppressor Gene

Merkel cell carcinoma (MCC) is an uncommon, lethal cancer of the skin caused by either Merkel cell polyomavirus (MCPyV) or UV-linked mutations. MCPyV is found integrated into MCC tumor genomes, accompanied by truncation mutations that render the MCPyV large T antigen replication incompetent. We used the open access HPV Detector/Cancer-virus Detector tool to determine MCPyV integration sites in whole-exome sequencing data from five MCC cases, thereby adding to the limited published MCPyV integration site junction data. We also systematically reviewed published data on integration for MCPyV in the human genome, presenting a collation of 123 MCC cases and their linked chromosomal sites. We confirmed that there were no highly recurrent specific sites of integration. We found that chromosome 5 was most frequently involved in MCPyV integration and that integration sites were significantly enriched for genes with binding sites for oncogenic transcription factors such as LEF1 and ZEB1, suggesting the possibility of increased open chromatin in these gene sets. Additionally, in one case we found, for the first time, integration involving the tumor suppressor gene KMT2D, adding to previous reports of rare MCPyV integration into host tumor suppressor genes in MCC.

Abstract 2045: Characterization of inpatient opioid use among pediatric neuroblastoma patients during dinutuximab therapy

Background: Dinutuximab is a chimeric anti-GD-2 (disialoganglioside) antibody approved for use in post-consolidation care of patients with high-risk neuroblastoma. GD-2 receptors are also expressed in cerebellar neurons, melanocytes, and peripheral sensory nerve fibers in normal human tissue. Given this pattern of expression, pain is a common and often infusion rate-limiting adverse effect, with greater than 50% of patients experiencing severe (Grade 3 or above) pain. Standard pain management for dinutuximab infusions at our center includes initiation of continuous infusion of opioid patient-controlled analgesia along with demand, loading, and boluses doses. Little to no data exist in the literature to describe opioid use in pediatric patients with acute, episodic pain. Therefore, this study aims to characterize opioid use in this setting.

Methods: Data were collected retrospectively from the electronic medical record under a study protocol approved by the Institutional Review Board at the University of Michigan, C.S. Mott Children's Hospital. Patients were included in the study if they had a clinical diagnosis of metastatic or relapsed high-risk neuroblastoma, received at least one dinutuximab cycle, and were aged 2-14 at the time of admission. Daily amount of opioids, calculated as the oral morphine equivalent daily dose (MEDD), acetaminophen, and gabapentin administered were calculated. Repeated measures ANOVA was used to evaluate within-subjects changes.

Results: The average age of patients was 5.7 years [range 2-14 years]. Four of eleven (36.4%) were female and 7/11 (63.6%) were male. All patients received four days of dinutuximab infusions for an average length of 11.8 hours (SD=2.0) per day. All patients received gabapentin prophylactic treatment and an average of 3387 mg (SD=1275.5). Average total MEDD across all patients was 184.7 mg (SD=137.6) during the inpatient hospitalization. Females (p=0.003) and older patients (p=0.04) had significantly increased daily MEDD as compared to their day 1 intake. All patients experienced a fever spike and received acetaminophen (2915 mg, SD=1737.8) Older patients received higher doses of acetaminophen (p=0.007) Only 1 patient met definition of a chronic opioid user and was discharged with an outpatient opioid prescription. The remaining opioid-naïve patients were discontinued on opioid treatment at the time of discharge.

Conclusions: Pediatric patients on dinutuximab therapy received a high MEDD parenteral opioids dose alongside adjunctive analgesics. Future studies are needed to determine opioid requirement trends across gender, age, and cycles in a larger cohort of patients, as well as to determine the risk of chronic opioid use in this patient population.

Citation Format: Jola Mehmeti, Jae Eun Choi, Ian Wolfe, Juan Cata, Rajen Mody. Characterization of inpatient opioid use among pediatric neuroblastoma patients during dinutuximab therapy [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 2045.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Psychoacoustics and neurophysiological auditory processing in patients with Charcot-Marie-Tooth disease types 1A and 2A

BACKGROUND AND PURPOSE

Hidden hearing loss has been reported in patients with Charcot-Marie-Tooth (CMT) disease; however, the auditory-processing deficits have not been widely explored. We investigated the psychoacoustic and neurophysiological aspects of auditory processing in patients with CMT disease type 1A (CMT1A) and type 2A (CMT2A).

METHODS

A total of 43 patients with CMT1A and 15 patients with CMT2A were prospectively enrolled. All patients with CMT disease had normal sound-detection ability by using pure-tone audiometry. Spectral-ripple discrimination, temporal modulation detection and auditory frequency-following response were compared between CMT1A, CMT2A and control groups.

RESULTS

Although all participants had normal audiograms, patients with CMT disease had difficulty understanding speech in noise. The psychoacoustic auditory processing was somewhat different depending on the underlying pathophysiology of CMT disease. Patients with CMT1A had degraded auditory temporal and spectral processing. Patients with CMT2A had no reduced spectral resolution, but they showed further reduced temporal resolution than the patients with CMT1A. The amplitudes of the frequency-following response were reduced in patients with CMT1A and CMT2A, but the neural timing remained relatively intact.

CONCLUSIONS

When we first assessed the neural representation to speech at the brainstem level, the grand average brainstem responses were reduced in both patients with CMT1A and CMT2A compared with healthy controls. As the psychoacoustic aspects of auditory dysfunctions in CMT1A and CMT2A were somewhat different, it is necessary to consider future auditory rehabilitation methods based on their pathophysiology.

Development and evaluation of an augmented reality education program for pediatric research

BACKGROUND

Children often have limited understanding of clinical research and what they might expect from participating in a clinical study. Studies, however, suggest that multimedia delivery of medical and research information may promote greater understanding and engagement compared with standard written approaches.

AIM

This study was designed to examine the effects of a novel interactive augmented reality (AR) program on children's understanding of clinical research.

METHODS

Children (ages 7-13 years) were randomized to receive the basic information about clinical research using either a printed storybook (control) or the same storybook enhanced using a video see-through AR iPad program (AR) with embedded interactive quizzes. Children were interviewed to assess their understanding of the material before (pre-test) and after (post-test) receiving either of the randomized interventions. Both parents and children completed short surveys to measure their perceptions of the information delivery.

RESULTS

Ninety-one parent/child dyads were included in the analysis. There were no differences between the control and AR children's pre-test understanding of the research information. However, both groups demonstrated significant and similar improvements in post-test understanding. Parents of children in the AR group found the information to be of higher quality and greater clarity compared with the control group, and 91.7% of children in the AR group found the inclusion of interactive quizzes to be helpful. Both parents and children found the AR program very easy to use and 85.0 % and 71.2%, respectively, indicated that if recruited for a future study that they would prefer information delivered using some type of iPad AR program together with a discussion with the researcher.

CONCLUSIONS

Results demonstrated the importance of providing children and parents with information in an easy to read and visually compelling manner. Although both groups demonstrated improved understanding, children and their parents preferred the AR program and reported a preference for receiving information using computer-based technology. Given the seemingly insurmountable challenge of keeping children and families engaged in health research related information exchange, the use of AR would appear to provide a novel and effective vehicle for enhancing children's and parents assimilation and understanding of research (and medical) information and as a potential tool to optimize the informed consent and assent processes.

RELEVANCE FOR PATIENTS

This study reinforces the importance in providing information to research participants and patients in an easy-to-read and visually salient manner. Although the AR program used in this study did not result in an increased level of understanding, AR was deemed the preferred method of information delivery. It is hoped that the results of this study will serve as a platform for future studies.

Radiotherapy and Immunotherapy Promote Tumoral Lipid Oxidation and Ferroptosis via Synergistic Repression of SLC7A11

A challenge in oncology is to rationally and effectively integrate immunotherapy with traditional modalities, including radiotherapy. Here, we demonstrate that radiotherapy induces tumor-cell ferroptosis. Ferroptosis agonists augment and ferroptosis antagonists limit radiotherapy efficacy in tumor models. Immunotherapy sensitizes tumors to radiotherapy by promoting tumor-cell ferroptosis. Mechanistically, IFNγ derived from immunotherapy-activated CD8⁺ T cells and radiotherapy-activated ATM independently, yet synergistically, suppresses SLC7A11, a unit of the glutamate-cystine antiporter xc^-, resulting in reduced cystine uptake, enhanced tumor lipid oxidation and ferroptosis, and improved tumor control. Thus, ferroptosis is an unappreciated mechanism and focus for the development of effective combinatorial cancer therapy. SIGNIFICANCE: This article describes ferroptosis as a previously unappreciated mechanism of action for radiotherapy. Further, it shows that ferroptosis is a novel point of synergy between immunotherapy and radiotherapy. Finally, it nominates SLC7A11, a critical regulator of ferroptosis, as a mechanistic determinant of synergy between radiotherapy and immunotherapy.This article is highlighted in the In This Issue feature, p. 1631.

Human Keratinocytes Use Sphingosine 1-Phosphate and its Receptors to Communicate Staphylococcus aureus Invasion and Activate Host Defense

Sphingosine 1-phosphate (S1P) is a bioactive lipid mediator generated when a cell membrane or its components are damaged by various factors. S1P regulates diverse cell activities via S1P receptors (S1PRs). Keratinocytes express S1PR1-5. Although it is known that S1PRs control keratinocyte differentiation, apoptosis, and wound healing, S1PR functions in keratinocyte infections have not been fully elucidated. We propose that the S1P-S1PR axis in keratinocytes works as a biosensor for bacterial invasion. Indeed, in human impetigo infection, we found high epidermal expression of S1PR1 and S1PR2 in the skin. Furthermore, in normal human epidermal keratinocytes in vitro, treatment with Staphylococcus aureus bacterial supernatant not only induced S1P production but also increased the transcription of S1PR2, confirming our in vivo observation, as well as increased the levels of TNFA, IL36G, IL6, and IL8 mRNAs. However, direct treatment of normal human epidermal keratinocytes with S1P increased the expressions of IL36G, TNFA, and IL8, but not IL6. In both S1P- and S. aureus bacterial supernatant-treated normal human epidermal keratinocytes, S1PR1 knockdown reduced IL36G, TNFA, and IL8 transcription, and the S1PR2 antagonist JTE013 blocked the secretion of these cytokines. Overall, we have proven that during infections, keratinocytes communicate damage by using S1P release and tight control of S1PR1 and 2.

Abstract 4091: Evaluating the efficacy of a STING agonist in a murine model of prostate cancer

Despite the promise of checkpoint inhibitor therapy, prostate cancer has remained resistant to this treatment. Innate immune agonists, however, have been shown to have anti-tumor effects in various cancer types, such as melanoma and colon cancer, and have been nominated to be used in combination with approved anti-PD1/PD-L1 drugs. For instance, STING agonist + anti-PD-1 combination therapy has been demonstrated in a syngeneic mouse model of melanoma. Other innate immune agonists, such as TLR7/8 and TLR9 have also been shown to have potential anti-tumor effects. We hypothesized that innate immune agonists may be effective in the MycCaP syngeneic mouse model of prostate cancer. To compare the efficacy of three innate agonists targeting the STING (3’3’ cGAMP), TLR7/8 (CL097), and TLR9 (ODN2395) pathways, FVB mice were first injected bilaterally with MycCaP subcutaneous tumors. Upon establishment of tumors, mice were administered 3 doses of a single-sided intratumoral injection of each drug. The injected tumors had responses of 50% (6/12), 23% (3/13), and 8% (1/13) for the STING, TLR7/8 and, TLR8 agonists, respectively. Contralateral tumors showed no significant regression.

Published data have reported inherent resistance of MycCaP tumors to anti-PD-1 treatment in vivo. Given our results, we hypothesize that the addition of a STING agonist could enhance efficacy of anti-PD-1 therapy in this model. Mice with MycCaP tumors were administered anti-PD1 alone (n=10) or in combination with bilateral injections of the STING agonist (n=14). Combined therapy resulted in significant reduction in tumor size (71%) compared to anti-PD1 alone (9%). Additionally, there was a significant increase in the Ifnb1 (p=.04), Ifng (p=.008), Tnf-α (p=.006), IRF3 (p=.003) and II6 (p<.0001) gene expression in the combination group showing enhancement of the STING pathway genes. Combined, these findings suggest that targeting the STING pathway may have a modest local anti-tumor effect when compared to other innate immune pathways in prostate cancer. The efficacy of anti-PD-1 therapy was significantly enhanced when combined with a STING agonist, possibly through enhancement STING pathway genes. Our data suggest that combination therapy with a STING agonist and anti-PD1 therapy may have potential anti-tumor efficacy in prostate cancer. Future studies will examine these effects on both local and abscopal tumors.

Citation Format: Jonathan Gurkan, Jae Eun Choi, Jean Tien, Marcin Cieślik, Luigi Franchi, Arul M. Chinnaiyan. Evaluating the efficacy of a STING agonist in a murine model of prostate 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 4091.

Abstract LB-031: A novel model of prostate cancer suggests enzalutamide functions through the immune system to diminish metastatic growth

Purpose: There is tremendous need for improved prostate cancer models. The murine prostate is anatomically and developmentally different from the human prostate, and unlike the human prostate, does not form sporadic tumors, limiting relevance of genetically engineered model systems. Furthermore, engineered models lack the heterogeneity of human disease, rarely (if ever) establish metastatic growth, and tend to be driven in a contrived manner, not at all related to human disease or the human drivers of disease progression. Human xenografts represent alternative models, but they rely on tumor growth in an immunocompromised murine host, preventing the study of tumor-immune interactions and immunotherapy interventions. Consequently, translational progress in prostate cancer research is hampered by the lack of human-derived models that can recapitulate the natural history of the disease—from initiation to metastatic spread—that will respond appropriately to the standard of care hormonal therapies. Accordingly, we generated a prostate cancer xenograft model in a murine system with an intact human immune system to test the hypothesis that humanizing tumor-immune interactions would improve modeling of metastatic prostate cancer, and further-enable improved modeling of hormonal and immune therapies.

Procedure: Male huNOG mice were produced at Taconic Biosciences by engrafting juvenile NOG mice with human CD34+ hematopoietic stem cells. These mice stably develop and maintain multiple human cell lineages, including functional human T-cells. HuNOG and NOG control mice were surgically castrated. One week following castration, castrated and intact control mice were injected subcutaneously with luciferase-transduced 22Rv1 human prostate cancer cells to assay organ-specific metastatic growth. After tumors reached 100mm3, half of the castrated mice were treated with enzalutamide, and then tumor growth was monitored to endpoint. At sacrifice, organs were ex-vivo analyzed for metastatic growth, tumor infiltrating lymphocytes, and splenic immune reconstitution.

Results: Primary tumor size was not significantly altered across conditions; however, the extent and growth at the secondary sites differed markedly in castrate huNOG vs conventional NOG mice treated with enzalutamide. Furthermore, enzalutamide responses in huNOG and NOG mice were distinct, and associated with increased CD3+ T-cells within tumors of enzalutamide treated huNOG mice, and increased CD3+ T-cell activation, accessed by intracellular interferon-γ. These results illustrate, to the best of our knowledge, the first model of human prostate cancer with metastases to clinically relevant locations, an intact human immune system, that responds appropriately to standard-of-care hormonal therapies.

Citation Format: Steven Kregel, Jae Eun Choi, Kristen Juckette, Brooke Mccollum, Stephanie Simko, Parth Desi, Yuanyuan Qiao, Paul A. Volden, Arul M. Chinnaiyan. A novel model of prostate cancer suggests enzalutamide functions through the immune system to diminish metastatic growth [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 LB-031.

IMPACT: Immunotherapy in patients with metastatic cancers and CDK12 mutations

TPS5091

Background: Tumors with biallelic CDK12 loss have been identified as a distinct subtype in metastatic castration resistant prostate cancer (mCRPC) and other cancer types. The CDK12 biallelic loss mCRPC genomic signature, distinct from homologous recombination deficient (HRD) and ETS fusion signatures, is characterized by excessive tandem duplications, genomic instability, gene fusion-caused putative neoantigens, and increased tumor T cell infiltration. Early clinical experience with anti-PD-1 immunotherapy in CDK12 loss mCRPC patients (pts) is notable for deep and sustained PSA as well as radiographic responses. We hypothesize that CDK12 biallelic loss is a potential biomarker of immune checkpoint immunotherapy (ICI) efficacy in mCRPC and other cancers. Methods: IMPACT (NCT03570619) is a multi-center, open label, phase 2 study of pts with metastatic cancers that harbor CDK12 biallelic loss. mCRPC pts will be enrolled in cohort A (n = 25) in a Mini-Max Simon Two-Stage design, and all other pts in single-stage cohort B (n = 15). All pts will receive induction therapy with nivolumab 3 mg/kg IV and ipilimumab 1 mg/kg IV q3 weeks for up to 4 cycles, followed by maintenance nivolumab at 480 mg IV q4 weeks (up to 52 weeks in total). Eligible pts must have identified biallelic CDK12 loss on any CLIA/CAP approved next generation sequencing assay and a histologic diagnosis of metastatic prostate adenocarcinoma or other metastatic carcinoma. No prior ICI is allowed. The primary endpoint is the overall response rate (ORR) in cohort A per PCWG3 criteria. An ORR of 30% is targeted in cohort A. Secondary endpoints include safety, secondary efficacy measures, quality of life, and survival measures. Exploratory objectives include tumor whole exome analysis and changes in immune profiles with therapy. Comprehensive and serial monitoring of peripheral blood immune cell populations will be performed via T cell clonal diversity assessment and multi-parametric flow cytometry. Changes in myeloid and lymphoid populations will be assessed from whole blood. Polarization and effector function of T cells and activation of antigen presenting cells will be further characterized from isolated peripheral blood mononuclear cells. Study accrual is ongoing. Clinical trial information: NCT03570619.

CD8+ T cells regulate tumor ferroptosis by targeting the system xc− during cancer immunotherapy

Cytotoxic T cells recognize specific antigens expressed on tumor cells and mediate tumor cell apoptosis mainly through perforin–granzyme-mediated and FAS-mediated pathways. Ferroptosis is a recently discovered form of cell death that differs from apoptosis and results from iron-dependent lipid peroxide accumulation. The potential contribution of CD8+ T cell-mediated cytotoxic activity and immunotherapy to tumor ferroptosis remains unknown. Here, we find that immunotherapy-activated CD8+ T cells sensitize tumor cell ferroptosis. Mechanistically, IFNγ released from CD8+ T cells downregulates expression of SLC3A2 and SLC7A11, two subunits of glutamate-cystine antiporter system xc−, restrains tumor cell cystine uptake, and as a consequence, promotes tumor cell lipid peroxidation and ferroptosis. In preclinical models, depletion of cyst(e)ine by cyst(e)inase in combination with checkpoint blockade synergistically enhances T cell-mediated anti-tumor immunity and induces tumor cell ferroptosis. Expression of glutamate-cystine antiporter system xc− is negatively associated with CD8+ T cell signature, IFNγ expression, and cancer patient outcome. Transcriptome analyses before and during nivolumab therapy reveal that clinical benefits correlate with reduced expression of SLC3A2 and increased IFNγ and CD8. Thus, T cell-promoted tumor ferroptosis is a novel anti-tumor mechanism. Targeting tumor ferroptosis pathway constitutes a therapeutic approach in combination with checkpoint blockade.

Sphingosine 1-phosphate is a harbinger of S. aureus invasion and activates host defense in epithelial barriers

Background

Sphingosine 1-phosphate (S1P) is a bioactive lipid mediator generated in the skin when cell membrane or barrier components are damaged. S1P regulates diverse cell activities via S1P receptors (S1PR). Keratinocytes express S1PR1–5. Although it is known that S1PRs control keratinocyte differentiation, apoptosis and wound healing, S1PR functions in keratinocyte infections are not fully elucidated. We hypothesized that S1P and S1PR-axis in keratinocytes works as a biosensor for bacterial invasion.

Methods

The expression of S1PRs were studied by immunofluorescence and qPCR. Cytokine transcription and secretion were detected by qPCR and ELISA, respectively. siRNA and S1PR2 antagonist, JTE013, were used to test the different S1PR functions. The S1P synthesis was tested by ATP depletion assay and ELISA.

Results

We found a high epidermal S1PR1 and 2 expressions in human impetigo skin. In vitro, in normal human epidermal keratinocytes (NHEK), S. aureus bacterial supernatant not only induced S1P production but also increased S1PR2 transcription and TNFα, IL36γ, 6 and 8 transcriptions, confirming our in vivo observation. S1P directly increased NHEK IL36γ, TNFα and IL8 expression, but not IL6. In both, S1P and S. aureus bacterial supernatant treated NHEK, S1PR1 knock down reduced IL36γ, TNFα and IL8 transcription, while S1PR2 antagonist, JTE013, blocked their protein secretion.

Conclusions

We proved that, during infections, keratinocytes communicate the infection by sensing S1P release and respond to it using receptors S1PR1 and 2, releasing pro-inflammatory cytokines.

Characterizing the Therapeutic Potential of a Potent BET Degrader in Merkel Cell Carcinoma

Studies on the efficacy of small molecule inhibitors in Merkel cell carcinoma (MCC) have been limited and largely inconclusive. In this study, we investigated the therapeutic potential of a potent BET degrader, BETd-246, in the treatment of MCC. We found that MCC cell lines were significantly more sensitive to BETd-246 than to BET inhibitor treatment. Therapeutic targeting of BET proteins resulted in a loss of "MCC signature" genes but not MYC expression as previously described irrespective of Merkel cell polyomavirus (MCPyV) status. In MCPyV+ MCC cells, BETd-246 alone suppressed downstream targets in the MCPyV-LT Ag axis. We also found enrichment of HOX and cell cycle genes in MCPyV- MCC cell lines that were intrinsically resistant to BETd-246. Our findings uncover a requirement for BET proteins in maintaining MCC lineage identity and point to the potential utility of BET degraders for treating MCC.

Abstract P2-08-53: Tumor elasticity and clinicopathologic factors affecting neoadjuvant chemotherapy response in breast cancer patients

Background: Neoadjuvant chemotherapy for breast cancer has been increased. Many studies have reported on clinicopathologic factors to predict neoadjuvant chemotherapy response. Elastography, which is usually used to differentiate benign and malignant tumors, can be performed to evaluate tissue elasticity during conventional ultrasonography. The purpose of this study was to determine the clinicopathologic factors, including tumor elasticity, that affect neoadjuvant chemotherapy response in stage II or III breast cancer patients.

Methods: From April 2014 to March 2017, 95 patients received neoadjuvant chemotherapy for clinical stage IIa-IIIc primary breast cancer. To evaluate tumor elasticity, strain elastography was performed in 74 patients before neoadjuvant chemotherapy. Patients were divided into two groups by the Tsukuba elasticity scoring system (soft group ≤3 vs. hard group ≥4). Histologic type, nuclear grade, tumor infiltrating lymphocytes (TILs), tumor cellularity, characteristics of stroma, and hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status were evaluated using core needle biopsy specimens obtained before neoadjuvant chemotherapy. Pathologic complete response (pCR) was defined as the absence of invasive carcinoma in breast (ypT0 and ypTis) and axillary lymph node (ypN0). Residual cancer burden (RCB) was also calculated in 79 cases and the cases were categorized into 2 groups; favorable RCB group (RCB-0 and I) and unfavorable RCB group (RCB-II and III).

Results: The mean age of patients was 46.43±8.62 years (range, 27-71 years) and the mean initial tumor size was 3.63±1.95cm (range, 2.1-12.8cm). Twenty-four patients (32.4%) were categorized into the soft group and 50 patients (67.6%) into the hard group. The mean tumor cellularity on core needle biopsy specimens and characteristics of stroma were not significantly different between the two groups (p=0.35 and p=0.79, respectively). Twenty-two patients achieved pCR (23.2%). The patients with pCR were more likely to have estrogen receptor (ER) or progesterone receptor (PR) negative breast cancer (p=0.04 and p=0.03). The rate of nuclear grade 3 was higher in patients with pCR than those without (p=0.03). Tumor elasticity was not correlated with pCR (p=0.28). Thirty patients (38.0%) achieved favorable RCB and forty-nine patients (62.0%) had unfavorable RCB. Not only the rates of ER negativity (p=0.05), PR negativity (p=0.03), nuclear grade 3 (p=0.01), and high TILs level (≥ 10%) (p=0.04) but also the mean TILs level (p=0.05) were significantly higher in the favorable RCB group compared withthe unfavorable RCB group. No significant difference in tumor elasticity was observed between the two groups (p=0.30). In univariate analyses, nuclear grade 3 (p=0.03), and high TILs level (≥10%) (p=0.04) were significantly correlated with favorable RCB. HR negativity was an independent predictor of favorable RCB in multivariate analysis (odds ratio, 2.93; 95% confidence interval, 1.04-8.28; p=0.04).

Conclusion: Tumor elasticity was not associated with pCR or RCB. HR negativity was an independent predictor for favorable RCB.Nuclear grade and TILs were also potential predictive factors for neoadjuvant chemotherapy response.

Citation Format: Park JY, Choi JE, Bae YK, Lee SJ. Tumor elasticity and clinicopathologic factors affecting neoadjuvant chemotherapy response in breast cancer patients [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 P2-08-53.

Abstract P3-03-02: Redo sentinel lymph node biopsy for ipsilateral breast tumor recurrence after breast conserving surgery with negative sentinel nodes: A pooled analysis from a systematic review and two institutes

Background:Cases of redo sentinel lymph node biopsy (SLNB) are growing according to the increase of ipsilateral breast tumor recurrence (IBTR) after breast-conservative surgery (BCS). To evaluate a feasibility of redo SLNB in patients with IBTR after negative SLN, we conveyed a pooled analysis using data from a systematic review and two institutes.

Materials and methods:A systematic search of PubMed was conducted to identify data of patient level from publications evaluating redo SLNB for cases with IBTR. Eligible patients who underwent BCS and were confirmed as negative axilla after SLNB were identified. An identification rate (IR) and a false-negative rate (FNR) were calculated. To identify FNR, we only included cases with back-up axillary node dissection (ALND) from retrieved data.

Results:In a systematic review, a total of 197 peer-reviewed publications were retrieved, of which 19 papers included patients who met eligibility criteria. Data from 464 patients were collected. In two-institutes, 38 cases with same criteria were identified. A total of 502 patient's data were pooled. The IR of redo-SLNB was 71.7% (360/502) in pooled data. For the FNR, data from 147 patients with back-up ALND after SLNB was analyzed. The FNR and accuracy of redo-SLNB were 9.8% (5/51) and 97% (142/147).

Conclusions:We found that the IR and the FNR of redo SLNB were 71.7% and 9.8%, respectively. Redo SLNB is reliable procedure for axillary staging in patients with IBTR after negative SLNB.

Citation Format: Yoon C-i, Bae SJ, Choi JE, Cha CH, Park SE, Ahn SG, Jeong J. Redo sentinel lymph node biopsy for ipsilateral breast tumor recurrence after breast conserving surgery with negative sentinel nodes: A pooled analysis from a systematic review and two institutes [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 P3-03-02.

Botulinum toxin blocks mast cells and prevents rosacea like inflammation

BACKGROUND

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

OBJECTIVES

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

METHODS

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

RESULTS

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

CONCLUSIONS

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.

Skin neurogenic inflammation

The epidermis closely interacts with nerve endings, and both epidermis and nerves produce substances for mutual sustenance. Neuropeptides, like substance P (SP) and calcitonin gene-related protein (CGRP), are produced by sensory nerves in the dermis; they induce mast cells to release vasoactive amines that facilitate infiltration of neutrophils and T cells. Some receptors are more important than others in the generation of itch. The Mas-related G protein-coupled receptors (Mrgpr) family as well as transient receptor potential ankyrin 1 (TRPA1) and protease activated receptor 2(Par2) have important roles in itch and inflammation. The activation of MrgprX1 degranulates mast cells to communicate with sensory nerve and cutaneous cells for developing neurogenic inflammation. Mrgprs and transient receptor potential vanilloid 4 (TRPV4) are crucial for the generation of skin diseases like rosacea, while SP, CGRP, somatostatin, β-endorphin, vasoactive intestinal peptide (VIP), and pituitary adenylate cyclase-activating polypeptide (PACAP) can modulate the immune system during psoriasis development. The increased level of SP, in atopic dermatitis, induces the release of interferon (IFN)-γ, interleukin (IL)-4, tumor necrosis factor (TNF)-α, and IL-10 from the peripheral blood mononuclear leukocytes. We are finally starting to understand the intricate connections between the skin neurons and resident skin cells and how their interaction can be key to controlling inflammation and from there the pathogenesis of diseases like atopic dermatitis, psoriasis, and rosacea.

Once-daily dosing of amikacin for treatment of Mycobacterium abscessus lung disease

SETTING

Tertiary referral centre, Samsung Medical Center, South Korea.

OBJECTIVE

To evaluate the pharmacokinetic parameters and toxicities of once-daily amikacin (AMK) dosing for lung disease due to Mycobacterium abscessus.

DESIGN

A retrospective review of 48 patients with M. abscessus lung disease who received once-daily AMK for 4 weeks between January 2012 and June 2015.

RESULTS

With a starting dose of 15 mg/kg/day and adjustment of AMK dose according to the peak serum level (Cmax), the Cmax target of 55-65 μg/ml was achieved in 31.3% (15/48) of patients in the first week, 68.8% (33/48) in week 2, 91.7% (44/48) in week 3 and 95.8% (46/48) in week 4. Transient nephrotoxicity developed in 6.3% (3/48) of patients and ototoxicity in 25.0% (6/24), which was determined by audiogram as hearing loss, asymptomatic in five patients and tinnitus in one. Multivariate analysis revealed that the highest drug concentration 12 h after administration was significantly associated with the development of toxicities (adjusted odds ratio 1.862, P = 0.047).

CONCLUSION

Our results suggest that once-daily AMK for 4 weeks with a target Cmax of 55-65 μg/ml can be used in patients with M. abscessus lung disease, with careful monitoring of toxicity.

Abstract P5-22-03: Arm node preserving surgery in primary breast cancer patients : 5 year experience

Background:

Lymphedema is one of the major complications of axillary lymph node dissection (ALND) in patients with breast cancer. Axillary reverse mapping (ARM) is the technique to find lymphatic drainage from the arm during ALND. The purpose of this study is to evaluate the efficacy of arm node preserving surgery using ARM for reducing the incidence of lymphedema after axillary lymph node dissection in breast cancer patients and its oncologic safety.

Methods:

From January 2009 to October 2014, 167 patients with primary breast cancer were included. In all patients, 1 mCi of 99mTc-phytate was injected at the ipsilateral subareolar plexus and for axillary reverse mapping, 2.5mL of methylene blue was injected into the subcutaneous area of the medial intermuscular groove of the ipsilateral upper arm. The injection site was massaged for at least 5 minutes with the arm lifted above the heart level. At least 15 minutes later, ALND was performed and blue-stained arm nodes were identified. Arm nodes that were enlarged, hard or looked suspicious for metastasis were removed and all other arm nodes were preserved. Arm circumference at 10cm proximal to the medial epicondyle were measured pre- and post-operatively for 2 years. Circumference difference between both upper arms (CD) was evaluated and lymphedema was defined as CD of ≥ 2cm. Follow-up studies were performed every 6 months for 5 years and then annually using mammography, ultrasonography, and/or positron emission tomography.

Results:

Among 167 patients, 125 patients (74.9%) had their arm node preserved (ANP) and 42 (25.1%) patients had their arm node removed (ANR). Statistically significant difference in the mean number of harvested nodes was observed between ANP group (17.85±6.74) and ANR group (20.17±6.08) (p=0.05). The mean number of total identified blue stained arm nodes were 1.35±0.84. The mean follow-up period for measurement of arm circumference was 16.62±8.36 months. The last measured CD between both upper arms was 0.19±0.67cm in ANP group and 0.67±0.92cm in ANP group (p=0.003). 20 patients complained subjective symptoms of lymphedema, 7 patients in ANP group and 13 patients in ANR group (5.6% vs 31%, p<0.001). Among them, one patient in ANP group and 6 patients in ANR group were diagnosed with lymphedema ( 0.8% vs 14.3%, p=0.001). The other 13 patients' CDs between both upper arms were below objective criteria of lymphedema. Follow-up studies were performed for 59.4±22.40 months. There were 16 cases of distant metastasis, 12 cases in ANP group, 4 cases in ANR group (9.6% vs 9.5%, p=1). Two patients in ANP group had distant metastasis and ipsilateral axillary recurrence simultaneously, but their TNM stages were already IIIc and IIb at the diagnosis. There's no solitary axillary recurrence.

Conclusion:

Arm node preserving surgery using axillary reverse mapping in breast cancer patients can reduce the incidence of lymphedema after axillary lymph node dissection and it simultaneously has oncologic safety.

Citation Format: Park JY, Choi JE, Bae YK, Lee SJ. Arm node preserving surgery in primary breast cancer patients : 5 year experience [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-03.

Features Causing Confusion between Basal Cell Carcinoma and Squamous Cell Carcinoma in Clinical Diagnosis

Background

Although squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) can be easily diagnosed clinically, proper diagnosis is sometimes difficult when based on clinical information alone.

Objective

To know what causes clinical misdiagnosis between SCC and BCC, and evaluate whether dermoscopy can improve diagnostic accuracy.

Methods

Clinical and dermoscopic photographs of inversely diagnosed cases (histologically confirmed BCC with a clinical impression of SCC or vice versa) were randomly presented to six dermatologists and the reasons for each correct or incorrect diagnosis were analyzed.

Results

Among 154 cases (SCCs or BCCs), 13 cases were inversely diagnosed; 9 SCCs were clinically misdiagnosed as BCC and 4 BCCs were clinically misdiagnosed as SCC. Clinically, scales, pigmentation and rolled border were meaningful factors to discern two carcinomas. Scales without both pigmentation and rolled border was favored for SCC, but BCC favored vice versa. Ulceration, telangiectasia and translucency contributed as confusing factors for proper diagnosis. Dermoscopy improved overall diagnostic accuracy to odds ratio 2.86.

Conclusion

SCC has a higher tendency to be clinically misdiagnosed as BCC than vice versa. Pigmentation and rolled border are factors causing misdiagnosis of SCC as BCC and BCC may be misdiagnosed as SCC in the presence of scaling. Dermoscopy seems to improve the clinical diagnostic accuracy but has limitations for some ambiguous lesions.

Rosacea Subtypes Visually and Optically Distinct When Viewed with Parallel-Polarized Imaging Technique

Background

Parallel-polarized light (PPL) photography evaluates skin characteristics by analyzing light reflections from the skin surface.

Objective

The aim of this study was to determine the significance of quantitative analysis of PPL images in rosacea patients, and to provide a new objective evaluation method for use in clinical research and practice.

Methods

A total of 49 rosacea patients were enrolled. PPL images using green and white light emitting diodes (LEDs) were taken of the lesion and an adjacent normal area. The values from the PPL images were converted to CIELAB coordinates: L^* corresponding to the brightness, a^* to the red and green intensities, and b^* to the yellow and blue intensities.

Results

A standard grading system showed negative correlations with L^* (r=−0.67862, p=0.0108) and b^* (r=−0.67862, p=0.0108), and a positive correlation with a^* (r=0.64194, p=0.0180) with the green LEDs for papulopustular rosacea (PPR) types. The xerosis severity scale showed a positive correlation with L^* (r=0.36709, p=0.0276) and a negative correlation with b^* (r=−0.33068, p=0.0489) with the white LEDs for erythematotelangiectatic rosacea (ETR) types. In the ETR types, there was brighter lesional and normal skin with white LEDs and a higher score on the xerosis severity scale than the PPR types.

Conclusion

This technique using PPL images is applicable to the quantitative and objective assessment of rosacea in clinical settings. In addition, the two main subtypes of ETR and PPR are distinct entities visually and optically.

Abstract P2-01-32: Second sentinel lymph node biopsy for patients with local recurrence after breast cancer surgery

Background: Sentinel lymph node biopsy(SLNB) has become standard procedure for primary breast cancer patients who have no tumor metastasis in sentinel lymph node(SLN). In this study, we evaluated feasibility and pathologic outcomes of second SLNB in patients with locally recurrent breast cancer and their follow-up results.

Methods: From January 2008 to December 2015, 114 patients underwent operation for locally recurrent breast cancer. In 42 patients of them, lymphatic mapping was performed for second SLNB. When SLN was visualized in lymphangiography, SLNB was performed. In the cases where SLN metastasis was confirmed, axillary lymph node dissection(ALND) was performed. Follow-up studies were performed every 6 months for 5 years and then annually.

Results: The mean interval to local recurrence from the initial surgery of breast cancer was 64.6±53.1 months. In 38 of 42 patients(90.5%), lymphatic mapping was successfully performed. There was no significant difference of success rate of lymphatic mapping according to previous operation method of breast and axilla or history of radiation therapy.

Aberrant lymphatic pathway was observed in 15 of 38 patients(39.5%). The rate of aberrant lymphatic pathway was higher in patients who underwent ALND previously then in patients who underwent SLNB only(81.8% vs 22.2%, p=0.001). In 6 patients who previously underwent ALND followed by radiation therapy, all their lymphatic pathway was altered. There was no significant difference of the rate of aberrant lymphatic pathway according to previous operation method of breast.

Of 38 patients in whom lymphatic mapping was successfully performed, 37 patients underwent SLNB. SLNs were identified in 31 patients(83.8%). There was no significant difference of success rate of SLNB according to previous operation method of breast and axilla or history of radiation therapy.

Of 31 patients whose SLNs were identified, 4 patients(12.9%) had tumor metastasis in their SLN. Among them, 3 patients underwent ALND but SLN was the only lymph node(LN) in which tumor metastasis was confirmed. The other patient underwent no further ALND because ipsilateral internal mammary LNs were only LNs in which tumor metastasis was confirmed in frozen section biopsy and micrometastasis was additionally confirmed in only one contralateral axillary LN in permanent biopsy.

The mean follow-up period after operation for local recurrence was 33.0±24.5 months. There were 10 cases(23.8%) of loco-regional recurrence or distant metastasis at 14 months of mean follow-up. Among them, one patient had ipsilateral axillary recurrence solitary at 11 months of follow-up. The patient underwent breast conserving surgery and SLNB for primary breast cancer which stage was I. Second SLNB for local recurrence was tried at 48 months after first operation but SLN was not identified. Because there was no evidence of axillary LN metastasis in preoperative image study, no further ALND was performed.

Conclusion: Second SLNB should be considered for patients with locally recurrent breast cancer because occult LN metastasis could be identified in the ipsilateral axilla or other site through aberrant lymphatic pathway. Further studies are needed to verify accuracy of axillary staging using second SLNB and also its oncologic safety.

Citation Format: Park JY, Song JH, Choi JE, Lee SJ. Second sentinel lymph node biopsy for patients with local recurrence after breast cancer surgery [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-32.