Abstract P1-05-03: JNK signaling regulates tumor cell–tumor-associated macrophage cross-talk in triple-negative breast cancer

Despite advances in our understanding of the molecular mechanisms underlying the aggressiveness of triple-negative breast cancer (TNBC), the contribution of tumor-associated macrophages (TAMs) to TNBC pathogenesis has not been therapeutically exploited. TAMs are the most abundant cell types in the tumor microenvironment (TME) and the key contributor to tumor progression and invasion. We have found that c-Jun NH2-terminal kinase (JNK), a member of the MAPK family and a major regulator of inflammation, contributes to TNBC tumorigenesis by promoting the cancer stem-like cell phenotype. However, whether the JNK pathway regulates TAMs and their cross-talk with tumor cells in TNBC remains unknown. Here, we tested the hypothesis that JNK signaling contributes to TNBC aggressiveness by promoting the tumor cell–TAM cross-talk that facilitates TNBC cell invasiveness.

We found that, among 80 patients with primary inflammatory breast cancer (IBC), TNBC tumors (n=18) had 2-fold more TAMs than non-TNBC tumors (n=62, P=0.05) and that high TAM counts were correlated with shorter disease-free survival of patients with IBC (P=0.05). Both JNK1 and c-Jun were highly activated in TAMs, and JNK-IN-8, a pan-inhibitor of JNK, suppressed c-Jun activation. JNK-IN-8 also increased expression of M1 macrophage markers (CD80 and HLA-DR) but reduced expression of TAM markers (CD163 and CD206), suggesting that JNK suppresses M1 macrophage differentiation but promotes TAM differentiation. Co-culture with TAMs significantly enhanced migration and invasion of HCC70 and MDA-MB-468 human and 4T1 murine TNBC cells. Similarly, an enhancement in TNBC cells migration and invasion was observed following culture with TAM-conditioned medium, suggesting that TAMs enhance TNBC cellular activities through paracrine signaling. In addition, inhibition of JNK signaling in TNBC cells or in TAMs by JNK-IN-8 significantly suppressed TAM-promoted enhancement of TNBC cell migration and invasion. These studies strongly suggest that JNK regulates M1/TAM differentiation and TNBC cell–TAM cross-talk. Furthermore, cytokine/chemokine profiling analysis showed that, of the identified molecules, MCP-1 (secreted by TAMs) and VEGF (secreted by TNBC cells) had the highest expression levels and that their expression was dramatically reduced following JNK-IN-8 treatment. Stimulation with recombinant VEGF increased proliferation of MDA-MB-468 cells, and stimulation with recombinant MCP-1 enhanced migration of the cells. These findings suggest that VEGF and MCP-1 are involved in JNK-mediated TNBC cell–TAM cross-talk.

Together, our results suggest that JNK signaling regulates tumor cell–TAM cross-talk through MCP-1– and/or VEGF-mediated paracrine signaling and that JNK is an important therapeutic target in TNBC. Further animal studies using JNK-knockout TNBC cells co-injected with TAMs are needed to confirm our in vitro findings.

Citation Format: Xie X, Otsuka S, Chu K, Lu AY, Tripathy D, Dalby KN, Hittelman WN, Van Laere S, Bartholomeusz C, Ueno NT. JNK signaling regulates tumor cell–tumor-associated macrophage cross-talk in triple-negative breast cancer [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 P1-05-03.

Genetic Predisposition to Bleeding during Oral Anticoagulant Therapy: Evidence for Common Founder Mutations (FIXVal-10 and FIXThr-10) and an Independent CpG Hotspot Mutation (FIXThr-10)

The recent discovery of five patients with coumarin sensitive FIX-variants due to a missense mutation in the FIX propeptide, either Ala-10Val or Ala-10Thr, has highlighted a novel type of genetic predisposition to bleeding during oral anticoagulant therapy (OAT). In the present study, we report six additional patients with such FIX variants. Haplotype analysis of FIX polymorphisms revealed a founder effect in the five German and Swiss patients with the Val-10 variant. Also, four Thr-10 variants detected in Germany, Switzerland and Great Britain derived from a common founder. Two Thr-10 variants from USA showed an independent de novo origin at a CpG dinucleotide that in general represents a mutation hotspot. These findings implicate the existence of additional subjects with corresponding variants in the populations of various countries. Even though the rare occurrence of these variants does not justify a general aPTT screening during OAT, it is recommended to monitor each bleeding event during OAT in males in order to exclude a genetic predisposition to bleeding by means of the following testing strategy: a) aPTT-testing in each bleeding complication of male patients during OAT, b) if aPTT is disproportionately prolonged, determination of FIX:C, and c) if FIX:C is disproportionately decreased as compared to FII:C, FVII:C and FX:C, sequencing of exon 2 of the FIX gene. This strategy will provide a cost-effective and safe procedure to identify patients that carry the FIX variants. Moreover, such a strategy accumulates data about the prevalence of these FIX mutations in a given population.

The use and discontinuation of hormone replacement therapy in women in South China

OBJECTIVE

The use of hormone replacement therapy (HRT) started later in China than in European countries. The purpose of the present study was to investigate HRT patterns and reasons for the initiation and discontinuation of HRT among women in South China.

METHODS

A telephone survey about menopausal status, the use of HRT, reasons for HRT discontinuation and duration of HRT treatment was conducted in 2014.

RESULTS

A total of 825 telephone surveys were carried out, and 217 previous HRT users and 390 current users were recruited for this study. Among these 607 subjects, 50.7% of the women sought out HRT for hot flushes, 41.6% for fatigue and 41.5% for sleeplessness. Approximately one-third (35.9%) of the patients abandoned HRT during the following year. The reasons for stopping HRT were mainly fear of breast and uterine cancer (28.4%), reduced menopausal symptoms (22.9%) and the inconvenience of taking pills or seeing a doctor (17.9%). The factors related to HRT discontinuation were the age when HRT was initiated (odds ratio 1.59, 95% confidence interval 1.19-2.13) and education level (odds ratio 0.78, 95% confidence interval 0.62-0.98).

CONCLUSIONS

The duration of HRT use in women in south China was short, and a high proportion of the women discontinued HRT. Given the high discontinuation rate and the low medical compliance, Chinese health-care providers still have much to do to let women know about the advantages and disadvantages of HRT and to encourage the use of HRT appropriately.

Utility of digital subtraction angiography-based collateral evaluation in medically treated acute symptomatic basilar artery stenosis

BACKGROUND AND PURPOSE

Although a stroke from atherosclerosis in the basilar artery (BA) often presents with mild initial stroke severity, it has heterogeneous clinical courses. We investigated the efficacy of digital subtraction angiography (DSA)-based collateral perfusion evaluation in association with long-term outcomes of medically treated symptomatic basilar artery stenosis.

METHODS

From a registry database of all consecutive patients with stroke, we included 98 medically treated patients (due to mild initial stroke severity) [National Institute of Health Stroke Scale (NIHSS) scores ≤ 4; symptomatic basilar artery stenosis, 70-99%] with available initial diagnostic DSA. Basilar collateral scoring was performed via the DSA, using a modified version of the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system in both the superior cerebellar artery and anterior/posterior-inferior cerebellar artery territories (score 0-8). The outcomes were designated as the 90-day modified Rankin Scale (mRS90) score (poor, 3-6). Student's t-test, chi-square test and logistic regression analyses were used to identify factors associated with a poor outcome.

RESULTS

The median initial NIHSS score was 2 [interquartile range (IQR), 0-3], median posterior circulation Alberta Stroke Program Early CT Score was 8 (IQR, 7-10), median collateral score was 7 (IQR, 7-8) and 20 (20.4%) had poor mRS90 scores. In multivariate analysis, poorer collateral scores (P = 0.003), higher NIHSS scores (P = 0.005) and lower posterior circulation Alberta Stroke Program Early CT Score (P = 0.017) were independently associated with a poor mRS90 score.

CONCLUSIONS

The DSA-based collateral scoring of the BA large branches might predict long-term outcome in medically treated symptomatic basilar artery stenosis with mild initial severity. Evaluation of BA collateral perfusion status might be useful to determine appropriate treatment strategies.

Clinical Applications of Simultaneous PET/MR Imaging Using (R)-[11C]-Verapamil with Cyclosporin A: Preliminary Results on a Surrogate Marker of Drug-Resistant Epilepsy

BACKGROUND AND PURPOSE

The development of resistance to antiepileptic drugs is explained well by the transporter hypothesis, which suggests that drug resistance is caused by inadequate penetration of drugs into the brain barrier as a result of increased levels of efflux transporter such as p-glycoprotein. To evaluate the brain expression of p-glycoprotein in patients with drug-resistant epilepsy, including neocortical epilepsy, we developed a noninvsive quantitative analysis including asymmetry indices based on (R)-[(11)C]-verapamil PET/MR imaging with cyclosporin A, a p-glycoprotein inhibitor.

MATERIALS AND METHODS

Six patients with drug-resistant epilepsy, 5 patients with drug-sensitive epilepsy, and 8 healthy controls underwent dynamic (R)-[(11)C]-verapamil PET/MR imaging with an intravenous infusion of cyclosporin A. Asymmetry indices [(Right Region - Left Region)/(Right Region + Left Region) × 200%] of the standard uptake values in each of the paired lobes were calculated.

RESULTS

All patients with drug-resistant epilepsy had significantly different asymmetry from the healthy controls, whereas all patients with drug-sensitive epilepsy had asymmetry similar to that in healthy controls. In the temporal lobe, the asymmetry indices of patients with left temporal lobe drug-resistant epilepsy were more positive than those of healthy controls (healthy controls: 4.0413 ± 1.7452; patients: 7.2184 ± 1.8237; P = .048), and those of patients with right temporal drug-resistant epilepsy were more negative (patients: -1.6496 ± 3.4136; P = .044). In addition, specific regions that had significant asymmetry were different between the lateral and medial temporal lobe epilepsy groups. In the frontal lobe, the asymmetry index of patients with right frontal lobe drug-resistant epilepsy was more negative than that in healthy controls.

CONCLUSIONS

We confirmed that statistical parametric mapping analysis by using asymmetry indices of (R)-[(11)C]-verapamil PET/MR imaging with cyclosporin A could be used as a surrogate marker for drug-resistant epilepsy, and this approach might be helpful for localizing or lateralizing the epileptic zone.

Promoterless gene targeting without nucleases ameliorates haemophilia B in mice

Site-specific gene addition can allow stable transgene expression for gene therapy. When possible, this is preferred over the use of promiscuously integrating vectors, which are sometimes associated with clonal expansion and oncogenesis. Site-specific endonucleases that can induce high rates of targeted genome editing are finding increasing applications in biological discovery and gene therapy. However, two safety concerns persist: endonuclease-associated adverse effects, both on-target and off-target; and oncogene activation caused by promoter integration, even without nucleases. Here we perform recombinant adeno-associated virus (rAAV)-mediated promoterless gene targeting without nucleases and demonstrate amelioration of the bleeding diathesis in haemophilia B mice. In particular, we target a promoterless human coagulation factor IX (F9) gene to the liver-expressed mouse albumin (Alb) locus. F9 is targeted, along with a preceding 2A-peptide coding sequence, to be integrated just upstream to the Alb stop codon. While F9 is fused to Alb at the DNA and RNA levels, two separate proteins are synthesized by way of ribosomal skipping. Thus, F9 expression is linked to robust hepatic albumin expression without disrupting it. We injected an AAV8-F9 vector into neonatal and adult mice and achieved on-target integration into ∼0.5% of the albumin alleles in hepatocytes. We established that F9 was produced only from on-target integration, and ribosomal skipping was highly efficient. Stable F9 plasma levels at 7-20% of normal were obtained, and treated F9-deficient mice had normal coagulation times. In conclusion, transgene integration as a 2A-fusion to a highly expressed endogenous gene may obviate the requirement for nucleases and/or vector-borne promoters. This method may allow for safe and efficacious gene targeting in both infants and adults by greatly diminishing off-target effects while still providing therapeutic levels of expression from integration.