Relationship between menopausal hormone therapy and incidence of fractures in postmenopausal women.

OBJECTIVE: Long-term protective effects of menopausal hormone therapy (MHT) at fractures with different doses and components are controversial. We analyzed the effect of MHT on the incidence of spine and femur fractures according to MHT type, age at commencement, duration and dose of hormones in Korean women. METHOD: This retrospective study evaluated propensity score-matched patients with MHT from the Korean National Health Insurance Service database. Among women aged ≥50 years with menopause between 2004 and 2007, spine and femur fracture incidence until 2017 was analyzed in 36,446 women who had received MHT for >1 year. Estrogen-progesterone therapy (EPT), estrogen-only therapy (ET) or tibolone therapy was conducted. RESULTS: EPT significantly lowered the incidence of spine and femur fractures with a conventional dose, but not with a low dose. Tibolone significantly decreased the incidence of spine fractures in women aged 50-59 years when used for >5 years, and the incidence of femur fractures in women older than 60 years when used for >3 years. ET significantly lowered the risk of femur fractures when estradiol was used for >5 years. CONCLUSION: In menopausal women, all MHT including conventional-dose EPT, ET and tibolone tended to lower the incidence of fractures. The effects, however, varied with the type of fracture and type of MHT.

CD1b glycoprotein, a crucial marker of thymocyte development during T cell maturation in cynomolgus monkeys.

Phenotypic markers that denote different developmental stages of thymocytes are important for understanding T cell development in the thymus. Here, we show that CD1b is a critical discriminator of thymocyte maturation stage in cynomolgus monkeys. CD1b was expressed by immature thymocytes prior to ß-selection, and its expression decreased as cells became fully mature in the thymus. MHC-I expression was lowest at the CD3loCD1b+ immature double-positive (DP) stage, while the ratio of CD1d:MHC-I expression was significantly higher at this stage than at other developmental stages. PLZF was expressed by < 0.2% of thymocytes; most PLZF+ thymocytes were CD3-/loCD1b+ immature DP thymocytes with the potential to produce IL-4. EOMES+ thymocytes, which accounted for > 2% of total thymocytes, were mostly CD3+CD1b- mature thymocytes and predominantly of the CD8 single-positive (SP) lineage. An unconventional CD8+ T cell subset expressing the NKG2AC+CXCR3+ innate-like T cell marker was identified within the EOMES+ CD8 SP lineage; these cells exhibited a memory phenotype. Taken together, these findings show that CD1b is a valuable discriminatory marker of thymocyte development. The data presented herein can be used to characterize the features of PLZF- and EOMES-associated unconventional T cells in the thymus.

Blood eosinophil related to maternal allergic rhinitis is associated with the incidence of allergic rhinitis in offspring: COCOA study.

OBJECTIVE: The identification of allergic rhinitis (AR) in early life is important for the target of intervention. AR is caused by various environmental factors, including house dust mites. We investigated the relationship between the Dermatophagoides farinae (Der f)-IgE and eosinophil in mothers with AR at delivery and the eosinophil levels and AR incidence in children. METHODS: The study participants were 983 mother-child pairs from the COhort for Childhood Origin of Asthma and Allergic Diseases. AR was diagnosed by a doctor at delivery in mother and at 3 years of age in offspring. The association between eosinophil level and AR was assessed using logistic regression analysis. RESULTS: The Der f-IgE level in mother having AR at delivery was associated with the mother's eosinophil level, and the mother's eosinophil level was associated with the child's eosinophil level both at age 1 and 3. The risk of AR at age 3 in children was increased according to increased eosinophil levels in mothers at delivery and in children both aged 1 and 3 years (adjusted odds ratio [aOR] and 95% confidence interval [CI]: 2.57 [1.14-5.78], 2.28 [1.02-5.13], respectively). The risk of childhood AR at the age of 3 is increased when both mothers and children have high eosiniophils (aOR and 95% CI: 2.62 [1.01-6.79], 1.37 [0.98-1.91]). CONCLUSIONS: Der f-IgE in mothers at delivery was related to eosinophil levels in mothers with AR and higher level of eosinophils in both mother and children was associated with the increased risk of AR incidence at the first 3 years of life of children.

Heterogeneity of circulating CD4+CD8+ double-positive T cells characterized by scRNA-seq analysis and trajectory inference.

The frequency of CD4+CD8+ double-positive (DP) T cells is highly associated with a variety of diseases. Recently, we used high-throughput single-cell RNA sequencing to show that circulating DP T cells in cynomolgus monkeys comprise nine heterogeneous populations. To better understand the characteristics of DP T cells, we analyzed 7601 cells from a rhesus monkey and detected 14,459 genes. Rhesus monkey DP T cells comprised heterogeneous populations (naïve, Treg-, Tfh-, CCR9+ Th-, Th17-, Th2-, Eomes+ Tr1-, CTL-, PLZF+ innate- and Eomes+ innate-like cells) with multiple potential functions. We also identified two new subsets using aggregated scRNA-seq datasets from the rhesus and the cynomolgus monkey: CCR9+ Th-like cells expressing ICAM2 and ITGA1, and PLZF+ innate-like cells that display innate-associated gene signatures such as ZBTB16, TYROBP, MAP3K8, and KLRB1. Trajectory inference of cell differentiation status showed that most DP T cells in the rhesus monkey were found in the mid-to-late pseudotime, whereas DP T cells from the cynomolgus monkey were found in early pseudotime. This suggests that DP T cells in rhesus monkeys may exhibit more diverse differentiation states than those in cynomolgus monkeys. Thus, scRNA-seq and trajectory inference identified a more diverse subset of the circulating DP T cells than originally thought.

Antibody-mediated blockade for galectin-3 binding protein in tumor secretome abrogates PDAC metastasis.

The major challenges in pancreatic ductal adenocarcinoma (PDAC) management are local or distant metastasis and limited targeted therapeutics to prevent it. To identify a druggable target in tumor secretome and to explore its therapeutic intervention, we performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis of tumors obtained from a patient-derived xenograft model of PDAC. Galectin-3 binding protein (Gal-3BP) is identified as a highly secreted protein, and its overexpression is further validated in multiple PDAC tumors and primary cells. Knockdown and exogenous treatment of Gal-3BP showed that it is required for PDAC cell proliferation, migration, and invasion. Mechanistically, we revealed that Gal-3BP enhances galectin-3-mediated epidermal growth factor receptor signaling, leading to increased cMyc and epithelial-mesenchymal transition. To explore the clinical impact of these findings, two antibody clones were developed, and they profoundly abrogated the metastasis of PDAC cells in vivo. Altogether, our data demonstrate that Gal-3BP is an important therapeutic target in PDAC, and we propose its blockade by antibody as a therapeutic option for suppressing PDAC metastasis.

A Corticothalamic Circuit Trades off Speed for Safety during Decision-Making under Motivational Conflict.

Decisions to act while pursuing goals in the presence of danger must be made quickly but safely. Premature decisions risk injury or death, whereas postponing decisions risk goal loss. Here we show how mice resolve these competing demands. Using microstructural behavioral analyses, we identified the spatiotemporal dynamics of approach-avoidance decisions under motivational conflict in male mice. Then we used cognitive modeling to show that these dynamics reflect the speeded decision-making mechanisms used by humans and nonhuman primates, with mice trading off decision speed for safety of choice when danger loomed. Using calcium imaging in paraventricular thalamus and optogenetic inhibition of the prelimbic cortex to paraventricular thalamus pathway, we show that this speed-safety trade off occurs because increases in paraventricular thalamus activity increase decision caution, thereby increasing approach-avoid decision times in the presence of danger. Our findings demonstrate that a discrete brain circuit involving the paraventricular thalamus and its prefrontal input adjusts decision caution during motivational conflict, trading off decision speed for decision safety when danger is close. We identify the corticothalamic pathway as central to cognitive control during decision-making under conflict.SIGNIFICANCE STATEMENT Foraging animals balance the need to seek food and energy against the conflicting needs to avoid injury and predation. This competition is fundamental to survival but rarely has a stable, correct solution. Here we show that approach-avoid decisions under motivational conflict involve strategic adjustments in decision caution controlled via a top-down corticothalamic pathway from the prelimbic cortex to the paraventricular thalamus. We identify a novel corticothalamic mechanism for cognitive control that is applicable across a range of motivated behaviors and mark paraventricular thalamus and its prefrontal cortical input as targets to remediate the deficits in decision caution characteristic of unsafe and impulsive choices.

Identification of Single Nucleotide Polymorphisms as Biomarkers for Recurrent Pregnancy Loss in Korean Women.

BACKGROUND: Single nucleotide polymorphisms (SNPs) are reportedly associated with repeated abortion. Thus, genetic analysis based on race is the key to developing accurate diagnostic tests. This study analyzed the genetic polymorphisms of recurrent pregnancy loss (RPL) patients among Korean women compared to the controls. METHODS: In 53 women of RPL group and 50 controls, the genetic analysis was performed. The genotype distribution and allele frequency were analyzed statistically for the difference between the two groups. The association between each SNP marker and RPL risk was analyzed. RESULTS: The genotypes of LEPR, endothelial nitric oxide synthase (eNOS), KDR, miR-27a, miR-449b, and tumor necrosis factor-alpha (TNF-α) were analyzed using odds ratio (OR) with 95% confidence intervals (CIs). Only the AG genotype of miR-449b (A>G) polymorphism showed significant association with the risk of RPL when compared to the AA genotype (OR, 2.39). The combination of GG/AG+GG/CA+AA genotypes for eNOS/miR-449b/TNF-α was associated with 7.36-fold higher risk of RPL (OR, 7.36). The GG/AG+GG combination for eNOS/miR-449b showed 2.43-fold higher risk for RPL (OR, 2.43). The combination of AG+GG/CA+AA genotypes for miR-449b/TNF-α showed a significant association with the risk of RPL (OR, 7.60). From the haplotype-based analysis, the G-G-A haplotype of eNOS/miR-449b/TNF-α and the G-A haplotype of miR-449b/TNF-α were associated with increased risk of RPL (OR, 19.31; OR, 22.08, respectively). CONCLUSION: There is a significant association between the risk of RPL and miR-449b/TNF-α combination, and therefore, genetic analysis for specific combined genotypes can be an important screening method for RPL in Korean women.

Cellular heterogeneity of circulating CD4+CD8+ double-positive T cells characterized by single-cell RNA sequencing.

Circulating CD4+CD8+ double-positive (DP) T cells are associated with a variety of disease states. However, unlike conventional T cells, the composition of this population is poorly understood. Here, we used single-cell RNA sequencing (scRNA-seq) to analyze the composition and characteristics of the DP T cell population circulating in the peripheral blood of cynomolgus monkeys. We found that circulating DP T cells not only contain a large number of naïve cells, but also comprise a heterogeneous population (CD4 CTL-, Eomes+ Tr1-, Th2-, Th17-, Tfh-, Treg-, CD8 CTL-, and innate-like cells) with multiple potential functions. Flow cytometry analysis revealed that a substantial number of the naïve DP T cells expressed CD8αß, as well as CD8αα, along with high expression of CD31. Moreover, the CD4hiCD8lo and CD4hiCD8hi populations, which express high levels of the CD4 coreceptor, comprised subsets characterized by helper and regulatory functions, some of which also exhibited cytotoxic functions. By contrast, the CD4loCD8hi population with high CD8 coreceptor expression comprised a subset characterized by CD8 CTL- and innate-like properties. Taken together, the data show that scRNA-seq analysis identified a more diverse subset of the circulating DP cells than is currently known, despite this population being very small.

Metformin use in cancer survivors with diabetes reduces all-cause mortality, based on the Korean National Health Insurance Service between 2002 and 2015.

ABSTRACT: Malignant neoplasms are the leading cause of death in Korea. We aimed to examine if metformin use in cancer survivors reduces all-cause mortality. This study was retrospectively designed based on data from the Korean National Health Insurance Service-National Health Screening Cohort (HEALS) between 2002 and 2015. The Kaplan-Meier estimator and log-rank test was performed to estimate the survival function according to metformin usage (3721 metformin non-users with diabetes, 5580 metformin users with diabetes, and 24,483 non-diabetic individuals). Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated using Cox proportional hazards regression models.The median follow-up duration was 4.2 years. The HRs (95% CIs) for all-cause mortality of metformin users and the non-diabetic group were 0.762 (0.683-0.850) and 1.055 (0.966-1.152) in men and 0.805 (0.649-0.999), and 1.049 (0.873-1.260) in women, respectively, compared with metformin non-users among diabetic cancer survivors, in a fully adjusted model. After stratifying metformin users into pre- and post-diagnosis of cancers, adjusted HRs (95% CIs) of pre- and post-diagnosis metformin users for all-cause mortality were 0.948 (0.839-1.071) and 0.530 (0.452-0.621) in men and 1.163 (0.921-1.469) and 0.439 (0.323-0.596) in women, respectively.Metformin use in cancer survivors with diabetes reduced overall mortality rates. In particular, metformin use after cancer diagnosis, not before cancer diagnosis, was inversely associated with overall mortality.Active treatment with metformin for diabetic cancer survivors after cancer diagnosis can improve their survival rates.

Metformin usage and the risk of colorectal cancer: a national cohort study.

PURPOSE: This study aimed to investigate the association between metformin usage and the risk of colorectal cancer (CRC) using data from the Korean National Health Insurance Service-National Health Screening Cohort database. METHODS: Data from the NHIS-HEALS cohort between 2002 and 2015 were longitudinally analyzed. Subjects were divided into three groups: metformin non-users with diabetes mellitus (DM), metformin users with DM, and no DM group. CRC was defined using the ICD-10 code (C18.0-C20.0) at the time of admission. Cox proportional hazard regression models were adopted after stepwise adjustment for confounders to investigate the association between metformin usage and colorectal cancer risk. RESULTS: During the follow-up period, of the total 323,430 participants, 2341 (1.33%) of the 175,495 males and 1204 (0.81%) of the 147,935 females were newly diagnosed with CRC. The estimated cumulative incidence of CRC was significantly different among the three groups based on Kaplan-Meier's survival curve (p values < 0.05 in both sexes). Compared with metformin non-users, hazard ratios (95% CIs) of metformin users and the no DM group were 0.66 (0.51-0.85) and 0.72 (0.61-0.85) in males and 0.59 (0.37-0.92) and 0.93 (0.66-1.29) in females, respectively, after being fully adjusted. CONCLUSIONS: Metformin users with diabetes appear to have a significantly lower risk of CRC compared with metformin non-users.

Metformin use in elderly population with diabetes reduced the risk of dementia in a dose-dependent manner, based on the Korean NHIS-HEALS cohort.

AIMS: The aim of this study is to investigate the association between metformin usage and dementia in an elderly Korean population. METHODS: Participants were divided into five groups: metformin non-users with diabetes mellitus (DM), metformin users with DM (low-, mid-, and high-users), and non-diabetic Individuals. Dementia was defined with primary diagnostic dementia codes according to the 10th edition of the International Classification of Diseases. To compare the incidence rate of dementia among the five groups, Kaplan-Meier estimates and log-rank test were employed. Also, to control the confounding factors, Cox proportional hazards regression models were fitted in a sequential adjustment. RESULTS: The median follow-up was 12.4 years. The overall incidence rate of dementia was 11.3% (8.4% in men and 13.9% in women). Compared with metformin non-users, hazard ratios (95% confidence intervals) of low-, mid-, and high-users and non-diabetic individuals for dementia were 0.97 (0.73-1.28), 0.77 (0.58-1.01), 0.48 (0.35-0.67), and 0.98 (0.84-1.15), respectively, in men, respectively, and 0.90 (0.65-0.98), 0.61 (0.50-0.76), 0.46 (0.36-0.58), and 0.92 (0.81-1.04), respectively, in women, after full adjustment of confounding variables. CONCLUSIONS: Metformin use in an elderly population with DM reduced dementia risk in a dose-response manner.

Metformin use reduced the overall risk of cancer in diabetic patients: A study based on the Korean NHIS-HEALS cohort.

BACKGROUND AND AIM: Several studies have reported the preventive effect of metformin on cancer development. This study aimed to investigate the relationship between use of metformin and risk of cancer in Koreans. METHODS AND RESULTS: This study was designed retrospectively using the National Health Insurance Service-National Health Screening Cohort conducted between 2002 and 2015. 40 to 69-year-old subjects who received a health screening examination from 2002 to 2003 were enrolled. Hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer were estimated in a multivariate Cox proportional regression analysis. A total of 323,430 subjects was enrolled (301,905 individuals without diabetes [No DM], 8643 diabetic patients with metformin treatment [metformin users], and 12,882 diabetic patients without metformin treatment [metformin non-users]). The median follow-up period was 12.7 years. Cumulative incidence of overall cancer was 7.9% (7.7, 10.3, and 11.1% in No DM, metformin users and non-users, respectively). Compared to metformin non-users, the fully adjusted HRs (95% CIs) of metformin users and No DM for overall cancer incidence were 0.73 (0.66-0.81) and 0.75 (0.64-0.88), respectively, in men and 0.83 (0.78-0.89) and 0.81 (0.72-0.92) in women. CONCLUSIONS: Diabetic patients receiving metformin treatment, and individuals without diabetes were at lower risk for cancer incidence than diabetic patients without metformin treatment.

Diabetes, Metformin, and Lung Cancer: Retrospective Study of the Korean NHIS-HEALS Database.

BACKGROUND: Metformin is the first option in managing type 2 diabetes mellitus (DM) and has pleotropic effects. We studied the incidence of lung cancer in patients who received metformin therapy. PATIENTS AND METHODS: This study was retrospectively designed and based on the Korean National Health Insurance Service-National Health Screening Cohort to determine whether metformin reduces lung cancer risk in the diabetic population. At baseline, all participants were 40 to 69 years old and were categorized into 3 groups: metformin nonrecipients with DM, metformin recipients with DM, and the nondiabetic group. RESULTS: A total of 336,168 individuals were included in the final analysis (314,291 nondiabetic individuals, 8806 metformin recipients, and 13,071 metformin nonrecipients). The study median follow-up period was 12.86 years. The estimated cumulative lung cancer incidence of metformin nonrecipients, metformin recipients, and the nondiabetic group was 1.80%, 1.97%, and 1.24% in men and 1.87%, 0.61%, and 0.41% in women, respectively (P < .05). Compared to metformin nonrecipients, the hazard ratios (95% confidence intervals) for lung cancer incidence of metformin recipients and the nondiabetic group were 1.287 (0.979-1.691) and 0.835 (0.684-1.019) in men and 0.664 (0.374-1.177) and 0.553 (0.359-0.890) in women, respectively. The hazard ratios (95% confidence intervals) were statistically significant in male ever smokers (0.784 [0.627-0.979]) and female nonsmokers (0.498 [0.320-0.774]) after stratification according to smoking status. CONCLUSION: Metformin therapy did not reduce lung cancer incidence in the diabetic population. However, individuals without DM were at a lower risk of lung cancer, especially in male ever smokers and female nonsmokers.

Metformin use reduced the risk of stomach cancer in diabetic patients in Korea: an analysis of Korean NHIS-HEALS database.

BACKGROUND: Diabetes mellitus (DM) increases atherosclerotic cardiovascular complications and cancer risks. Stomach cancer is the most common cancer in Korea. Although the survival rate of stomach cancer has improved, the disease burden is still high. METHODS: This retrospective study investigated the association between metformin use and stomach cancer incidence in a Korean population using the National Health Insurance Service-National Health Screening Cohort database. Participants aged 40-80 years old at the baseline period (2002-2003) were enrolled. The study population was categorized into three groups of metformin non-users with DM, metformin users with DM, and individuals without DM (No DM group). RESULTS: A total of 347,895 participants (14,922 metformin non-users, 9891 metformin users, and 323,082 individuals without DM) were included in the final analysis. The median follow-up duration was 12.70 years. The estimated cumulative incidence of stomach cancer was highest in metformin non-users and lowest in the No DM group (men vs. women: 3.75 vs. 1.97% in metformin non-users, 2.91 vs. 1.53% in metformin users, and 2.54 vs. 0.95% in the No DM group). Compared with metformin non-users, the hazard ratios (95% confidence intervals) for stomach cancer incidence of metformin users and the No DM group were 0.710 (0.579-0.870) and 0.879 (0.767-1.006) in men and 0.700 (0.499-0.981) and 0.701 (0.544-0.903) in women, respectively, after full adjustment. CONCLUSIONS: Metformin users with DM in the Korean population were at lower risk of stomach cancer incidence after controlling for potential confounding factors.

Statin use increased new-onset diabetes in hypercholesterolemic individuals: Data from the Korean National Health Insurance Service-National Health Screening Cohort database (NHIS-HEALS).

AIM: We investigated the association between statin use and new-onset diabetes (NODM) in Korean adults with hypercholesterolemia. METHODS: This study performed based on data from the National Health Insurance Service-National Health Screening Cohort for the years from 2002 to 2015. Statin users classified as high- or low- users according to medication possession ratio. Statin non-users consisted of hypercholesterolemic participants who never used statin over the entire follow-up period. 21,469 participants (10,880 statin users, 10,589 statin non-users) with a median follow-up period of 12.5 years were included. We estimated the NODM risk based on the survival analyses. In particular, to adjust for confounding effects, we considered Cox proportional hazards regression models over three stages. RESULTS: Compared to non-users, statin users had a significantly higher risk for NODM. The fully adjusted hazard ratios (aHRs) (95% confidential intervals [95% CIs]) of statin users for NODM were 1.43 (1.31-1.57) in men, and 1.86 (1.66-2.10) in women, respectively after adjusted confounding factors including age and lifestyle factors. Compared to high-users, aHRs (95% CIs) of low-users for NODM were 1.16 (1.03-1.30) and 1.28 (1.16-1.43) in men and women, respectively. CONCLUSIONS: In hypercholesterolemic patients, statin users have a higher risk of NODM than non-users.

Association between statin use and all-cause mortality in cancer survivors, based on the Korean health insurance service between 2002 and 2015.

BACKGROUND AND AIMS: Cancer is the number one cause of death in Korea. This study aimed to investigate if statin use in cancer survivors was inversely associated with all-cause mortality. METHODS AND RESULTS: Data from the 2002 to 2015 National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) were used. The Kaplan-Meier estimator was used to estimate the survival function according to statin usage. Cox proportional hazards regression models were adopted after stepwise adjustment for potential confounders to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality. The median follow-up duration was 10.0 years. Statin users had a higher percentage of diabetes and hypertension in both sexes. Survival rates of statin users were higher than non-users (p-values <0.001 in men and 0.021 in women). Compared to non-users, the HRs (95% CIs) of statin users for all-cause mortality were 0.327 (0.194-0.553) in men and 0.287 (0.148-0.560) in women after adjustment for potential confounding factors. CONCLUSIONS: Statin users in cancer survivors had higher survival rate than non-users in both sexes.

A pharmacogenomic analysis using L1000CDS2 identifies BX-795 as a potential anticancer drug for primary pancreatic ductal adenocarcinoma cells.

Pancreatic cancer is one of the leading causes of cancer death, mainly due to the absence of early diagnostic tool and effective therapeutic agents. To identify an effective therapeutic agent for pancreatic ductal adenocarcinoma cells (PDAC), we used 10 Gene Expression Omnibus (GEO) data sets and L1000CDS2 pharmacogenetic search tool and obtained chemical "perturvants" that were predicted to reverse the abnormal gene expression changes in PDAC. Among 20 initial candidates, we measured IC50 for six compounds and identified BX-795, PDK1/TBK1 inhibitor, as a therapeutic candidate. We found that BX-795 inhibits primary PDAC cell proliferation more effectively than normal cells. Following molecular analysis revealed that BX-795 down-regulates mTOR-GSK3ß pathway and trigger apoptosis. Moreover, we found that BX-795 suppresses primary PDAC cell migration via downregulation of Snail and Slug. Finally, efficacy test in patient-derived xenograft model of PDAC showed BX-795 can inhibit in vivo tumor growth as efficient as gemcitabine and a combination with trametinib further suppresses tumor growth. Collectively, these results demonstrate the BX-795 as an effective therapeutic candidate for PDAC treatment.

Paraventricular Thalamus Controls Behavior during Motivational Conflict.

Decision-making often involves motivational conflict because of the competing demands of approach and avoidance for a common resource: behavior. This conflict must be resolved as a necessary precursor for adaptive behavior. Here we show a role for the paraventricular thalamus (PVT) in behavioral control during motivational conflict. We used Pavlovian counterconditioning in male rats to establish a conditioned stimulus (CS) as a signal for reward (or danger) and then transformed the same CS into a signal for danger (or reward). After such training, the CS controls conflicting appetitive and aversive behaviors. To assess PVT involvement in conflict, we injected an adeno-associated virus (AAV) expressing the genetically encoded Ca2+ indicator GCaMP and used fiber photometry to record population PVT Ca2+ signals. We show distinct profiles of responsivity across the anterior-posterior axis of PVT during conflict, including an ordinal relationship between posterior PVT CS responses and behavior strength. To study the causal role of PVT in behavioral control during conflict, we injected AAV expressing the inhibitory hM4Di DREADD and determined the effects of chemogenetic PVT inhibition on behavior. We show that chemogenetic inhibition across the anterior-posterior axis of the PVT, but not anterior or posterior PVT alone, disrupts arbitration between appetitive and aversive behaviors when they are in conflict but has no effect when these behaviors are assessed in isolation. Together, our findings identify PVT as central to behavioral control during motivational conflict.SIGNIFICANCE STATEMENT Animals, including humans, approach attractive stimuli and avoid aversive ones. However, they frequently face conflict when the demands of approach and avoidance are incompatible. Resolution of this conflict is fundamental to adaptive behavior. Here we show a role for the paraventricular thalamus, a nucleus of the dorsal midline thalamus, in the arbitration of appetitive and aversive behavior during motivational conflict.

A drug-repositioning screen for primary pancreatic ductal adenocarcinoma cells identifies 6-thioguanine as an effective therapeutic agent for TPMT-low cancer cells.

Pancreatic cancer is one of the most difficult cancers to cure due to the lack of early diagnostic tools and effective therapeutic agents. In this study, we aimed to isolate new bioactive compounds that effectively kill pancreatic ductal adenocarcinoma (PDAC) cells, but not untransformed, human pancreatic ductal epithelial (HPDE) cells. To this end, we established four primary PDAC cell lines and screened 4141 compounds from four bioactive-compound libraries. Initial screening yielded 113 primary hit compounds that caused over a 50% viability reduction in all tested PDAC cells. Subsequent triplicate, dose-dependent analysis revealed three compounds with a tumor cell-specific cytotoxic effect. We found that these three compounds fall into a single category of thiopurine biogenesis. Among them, 6-thioguanine (6-TG) showed an IC50 of 0.39-1.13 µm toward PDAC cells but had no effect on HPDE cells. We propose that this cancer selectivity is due to differences in thiopurine methyltransferase (TPMT) expression between normal and cancer cells. This enzyme is responsible for methylation of thiopurine, which reduces its cytotoxicity. We found that TPMT levels were lower in all four PDAC cell lines than in HPDE or Panc1 cells, and that knockdown of TPMT in HPDE or Panc1 cells sensitized them to 6-TG. Lastly, we used a patient-derived xenograft model to confirm that 6-TG has a significant antitumor effect in combination with gemcitabine. Overall, our study presents 6-TG as a strong candidate for use as a therapeutic agent against PDAC with low levels of TPMT.

Paraventricular Thalamus Balances Danger and Reward.

Foraging animals balance the need to seek food and energy against the accompanying dangers of injury and predation. To do so, they rely on learning systems encoding reward and danger. Whereas much is known about these separate learning systems, little is known about how they interact to shape and guide behavior. Here we show a key role for the rat paraventricular nucleus of the thalamus (PVT), a nucleus of the dorsal midline thalamus, in this interaction. First, we show behavioral competition between reward and danger: the opportunity to seek food reward negatively modulates expression of species-typical defensive behavior. Then, using a chemogenetic approach expressing the inhibitory hM4Di designer receptor exclusively activated by a designer drug in PVT neurons, we show that the PVT is central to this behavioral competition. Chemogenetic PVT silencing biases behavior toward either defense or reward depending on the experimental conditions, but does not consistently favor expression of one over the other. This bias could not be attributed to changes in fear memory retrieval, learned safety, or memory interference. Rather, our results demonstrate that the PVT is essential for balancing conflicting behavioral tendencies toward danger and reward, enabling adaptive responding under this basic selection pressure.SIGNIFICANCE STATEMENT Among the most basic survival problems faced by animals is balancing the need to seek food and energy against the accompanying dangers of injury and predation. Although much is known about the brain mechanisms that underpin learning about reward and danger, little is known about how these interact to solve basic survival problems. Here we show competition between defensive (to avoid predatory detection) and approach (to obtain food) behavior. We show that the paraventricular thalamus, a nucleus of the dorsal midline thalamus, is integral to this behavioral competition. The paraventricular thalamus balances the competing behavioral demands of danger and reward, enabling adaptive responding under this selection pressure.