Abstract 4471: Reprogramming “cold” NF1 malignancies into “hot” tumors for immunotherapy

Introduction: Neurofibromatosis Type 1 (NF1) results from mutations in the NF1 gene that inactivate the tumor suppressor, neurofibromin. This leads to hyperactive RAS signaling that predisposes NF1 patients to tumor development. Over time, some of these tumors can develop into malignant peripheral nerve sheath tumors (MPNST) which are currently incurable.Immune checkpoint blocking (ICB) programs a patient’s immune system to enhance tumor destruction. However, MPNSTs are cold tumors characterized by low immune cell presence in the tumor microenvironment. Interestingly, MPNSTs show checkpoint protein PD-L1 expression suggesting ICB as potential therapy for MPNST, given the ability to increase immune cell density in the tumor microenvironment. Activation of the intracellular receptor stimulator of interferon genes (STING) enhances antitumor immunity through the induction of pro-inflammatory cytokines and chemokines, including type I interferons. Cyclic GMP-AMP synthase (cGAS) is an enzyme that once bound to cytosolic DNA, synthesizes cyclic GMP-AMP (cGAMP), which activates STING to induce inflammatory cytokines and other immune mediators. Preclinical studies using mouse tumor models have assessed the efficacy of STING agonists that trigger the cGAS-STING-IFN axis, ultimately leading to augmented innate immunity and a T cell-rich tumor environment. Additionally, combining STING agonists with ICB has a synergistic effect in treating tumors. Therefore, we hypothesize that treatment with STING agonists would turn “cold” MPNSTs into “hot” tumors making them susceptible to targeting with ICB.

Methods: We treated MPNST cell lines with synthetic STING agonist ADU-S100 for varying durations of 8, 18, 24, and 48 hours. At the end of the treatment, cells were harvested for qRT-PCR and immunoblot analysis.

Results: We measured STING-IFN pathway activation through immunoblotting and observed that phosphorylation of STING effector proteins - a readout of STING activation – was increased followingby 8 hours after treatment. qRT-PCR analysis showed that STING target cytokine/chemokine gene expression was also upregulated by 8 hours after ADU-S100 treatment.

Conclusions: Theise data demonstrates that ADU-S100 was able to activate the STING pathway in MPNST cell lines leading to proinflammatory cytokine/chemokine production. We will next test STING agonist in vivo use to determine whether ADU-S100 treatment inin mouse MPNST modelss of MPNST to is able to reprogram the tumor microenvironment into an immune inflamed one amenable to immunotherapy.

Citation Format: Laasya Madana, Lu Q. Le, Nipunika Somatilaka, Renee McKay. Reprogramming “cold” NF1 malignancies into “hot” tumors for immunotherapy. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4471.

Acute interstitial nephritis, a potential predictor of response to immune checkpoint inhibitors in renal cell carcinoma

Immune checkpoint inhibitors (ICIs) such as nivolumab and ipilimumab have improved outcomes in metastatic renal cell carcinoma (mRCC) patients, but they are also associated with immune-related adverse events (irAEs). As observed in melanoma, we hypothesized that patients experiencing an autoimmune reaction directed against the tissue of origin may be more likely to benefit from ICI. Specifically, we asked whether patients with immune-related acute interstitial nephritis (irAIN) exhibited improved outcomes. Using Kidney Cancer Explorer (KCE), a data portal and i2b2-based central database for clinical, pathological and experimental genetic data, we systematically identified all patients with mRCC at UT Southwestern Medical Center (UTSW) from 2014-2018 who received at least one dose of ICI. More recent cases were identified through a provider query. We extracted creatinine (Cr) values at baseline and over the entirety of each patient ICI treatment course using KCE. Patients with ≥ 1.5-fold Cr increase over baseline were investigated. The likelihood of irAIN was determined based on the work-up (biopsy, if available), or by clinical criteria (timing of kidney injury, exclusion of other etiologies, treatment with immunosuppressants and response). We identified 177 mRCC patients who received at least one dose of ICI, 36 of whom had ≥ 1.5-fold increase in Cr over baseline while on treatment. Of those, two had biopsy-proven irAIN and one was clinically diagnosed, resulting in an incidence of 1.7%. One additional biopsy-proven case past 2018 was identified through a provider query, for a total of four patients. Two received combination nivolumab and ipilimumab in the first line, whereas the remaining received nivolumab after first line therapy. irAIN onset ranged from 1.5 to 12 months. All four patients stopped ICI with recovery of renal function, at least partially, three after receiving systemic steroids. Notably, all four patients had a deep response. In conclusion, irAIN is a rare event, but it may portend a higher likelihood of response. One possible explanation is antigenic overlap between normal renal tubular cells and tumor cells.

Pancreatic tropism of metastatic renal cell carcinoma

Renal cell carcinoma (RCC) is characterized by a particularly broad metastatic swath, and, enigmatically, when the pancreas is a destination, the disease is associated with improved survival. Intrigued by this observation, we sought to characterize the clinical behavior, therapeutic implications, and underlying biology. While pancreatic metastases (PM) are infrequent, we identified 31 patients across 2 institutional cohorts and show that improved survival is independent of established prognostic variables, that these tumors are exquisitely sensitive to antiangiogenic agents and resistant to immune checkpoint inhibitors (ICIs), and that they are characterized by a distinctive biology. Primary tumors of patients with PM exhibited frequent PBRM1 mutations, 3p loss, and 5q amplification, along with a lower frequency of aggressive features such as BAP1 mutations and loss of 9p, 14q, and 4q. Gene expression analyses revealed constrained evolution with remarkable uniformity, reduced effector T cell gene signatures, and increased angiogenesis. Similar findings were observed histopathologically. Thus, RCC metastatic to the pancreas is characterized by indolent biology, heightened angiogenesis, and an uninflamed stroma, likely underlying its good prognosis, sensitivity to antiangiogenic therapies, and refractoriness to ICI. These data suggest that metastatic organotropism may be an indicator of a particular biology with prognostic and treatment implications for patients.

Investigating Tongue Strength and Endurance in Children Aged 6 to 11 Years

Objective measures of tongue strength and endurance are used to assess lingual weakness and fatigue, and may have significant clinical value for dysphagia management. Recent studies investigating age and gender effects on tongue strength in children are limited by small sample sizes. The current study investigated age and gender effects on tongue strength with a larger sample size, and collected preliminary normative data for a paediatric population. This study also investigated the reliability of tongue endurance measures in children using a modified method, which has not previously been investigated. Using a cross-sectional design, this study examined tongue strength and endurance in 119 children aged 6 to 11 years, with no history of speech sound disorders, oro-motor deficits, dysphagia or cognitive impairment. Measures were collected using the Iowa Oral Performance Instrument. Children participated in two sessions, 45 min and 10 min in duration. Tongue strength was found to significantly increase with age (p < 0.001), while no gender effects were found. Modified tongue endurance measures involved using only one measure of maximal tongue strength to set parameters for tongue endurance scores. Despite this modification, data did not reach acceptable test-retest reliability, ICC = 0.68, p < 0.001; however, reliability improved from previous studies. These findings provide normative data for tongue strength, as a basis to compare individuals, and highlights the need for more reliable protocols for measuring tongue endurance. Normative data was collected from city-dwelling Australian children.

Abstract 2505: Comprehensive molecular and genomic characterization of pancreatic tropism in metastatic renal cell carcinoma

Introduction & Objectives: Patients with metastatic renal cell carcinoma (mRCC) involving the pancreas have been shown to exhibit a relatively indolent course, yet the biologic explanation is unclear. We sought to characterize the genomic landscape of patients with mRCC harboring pancreatic metastases (PM) to identify molecular drivers of pancreatic tropism.

Materials & Methods: mRCC patients harboring PM from UTSW and Cleveland Clinic were identified. Clinicopathologic data and oncologic outcomes were analyzed. Samples were obtained from primary tumors, metastatic sites (including pancreatic or other distant metastases), and matched normal tissue. Whole exome (WES) and RNA sequencing of tumors was conducted. Patient-derived xenograft (PDX) models were generated from a subset of patients, and the engrafted tumors were analyzed.

Results: 31 mRCC patients with PM were included with 54 tumor samples derived from the primary tumor or thrombus (24), PM (21), or other metastatic sites (9). Median follow-up was 101 months. Clinicopathologic characteristics were similar between the two institutional cohorts, and all but one patient were favorable or intermediate IMDC risk. All patients had clear cell histology. 8 patients (26%) were metastatic at diagnosis, and median time to metastasis in the remaining patients was 74 months (IQR 32-120). Overall (OS) and cancer-specific (CSS) survival did not vary by IMDC risk group. OS was strikingly superior for mRCC patients with PM than a historic control of mRCC patients without PM (p&lt;0.001), even after controlling for IMDC risk score. Morphologically, tumors largely displayed low-grade acinar patterns. WES with matched normal tissue and RNAseq were completed with adequate quality for 48 and 30 samples, respectively. 14 PDX lines were generated, of which 5 (36%) engrafted stably (≥2 passages). WES from 2 tumorgraft specimens revealed preservation of specific mutations in the corresponding human samples.

Conclusions: mRCC patients with PM exhibit remarkably favorable survival outcomes. The relatively indolent biology of these tumors is reflected histologically and genomically and can be recapitulated in PDX models. Understanding tumor heterogeneity may help refine prognostic models for mRCC and hold implications for improved personalization of therapy.

Citation Format: Nirmish Singla, Jacob Choi, Oreoluwa Onabolu, Layton Woolford, Christina Stevens, Vanina Tcheuyap, Tiffani McKenzie, Zhiqun Xie, Tao Wang, Renee McKay, Alana Christie, Payal Kapur, Brian Rini, James Brugarolas. Comprehensive molecular and genomic characterization of pancreatic tropism in metastatic renal cell carcinoma [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 2505.

Leveraging a robust patient-derived xenograft platform to characterize predictors for engraftment and oncologic outcomes in renal cell carcinoma patients

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Background: Patient-derived xenograft (PDX) models of renal cell carcinoma (RCC) preserve the biological features of patient tumors, providing a platform for biomarker identification and preclinical drug testing. We sought to identify predictors of successful tumor engraftment and evaluate the prognostic value of engraftment in patients with RCC using a robust murine PDX platform. Methods: 1,200 specimens derived from nephrectomy, thrombectomy, metastasectomy, or biopsy were orthotopically (renally) implanted into NOD/SCID mice between 2008-2018. Non-RCC pathology was excluded. Stable engraftment was defined by successful passage of tumor tissue at least twice with histologic confirmation. Clinicopathologic characteristics were stratified by engraftment status, and multivariate (MVA) logistic regression was used to identify predictors of engraftment. Kaplan-Meier and Cox regression analyses were used to assess the prognostic value of engraftment on patient overall (OS) and disease-free (DFS) survival. Results: 1,003 independent PDX lines derived from 770 RCC patients were included. 157 (15.6%) lines successfully engrafted and exhibited higher tumor grade, stage, size, and presence of sarcomatoid or rhabdoid components. 79.3% of all tumors were of clear cell histology, and histologic distribution did not vary by engraftment status. We have completed whole exome sequencing and RNAseq on 197 and 213 PDX lines, respectively, and downstream analyses will be reported. On MVA, sarcomatoid (OR 5.71, p < 0.001), rhabdoid (OR 2.79, p = 0.046), and advanced stage (OR 1.72, p = 0.049) were significant predictors for engraftment, while high grade and metastatic tumor source were significant only on UVA. Engraftment was associated with poor OS (HR 2.11, p < 0.001) and DFS (HR 1.85, p = 0.020) in patients after controlling for sarcomatoid, rhabdoid, grade, stage, and age on MVA. Conclusions: Aggressive RCC biology correlates with successful engraftment in PDX models. Engraftment remains independently predictive of OS and DFS even after controlling for adverse pathologic features. Engraftment in mice may illuminate aspects of tumor biology not captured by clinicopathologic variables and provide insight into novel determinants of tumor aggressiveness and metastasis.

Unraveling the molecular profile underpinning pancreatic tropisms in metastatic clear cell renal cell carcinoma

e16096

Background: The tropism of cancer metastases is poorly understood yet holds prognostic value. Clear cell renal cell carcinoma (ccRCC) exhibits a broad pattern of metastases, making it an optimal model to study organotropism. Notably, when ccRCC metastasizes to the pancreas (PM) independently of other sites, it is associated with favorable outcomes in patients for unclear reasons. Here, we comprehensively analyzed the clinical and molecular profile of patients with PM. Methods: RCC patients with PM from UTSW and Cleveland Clinic were identified. Clinicopathologic data and oncologic outcomes were analyzed. Whole exome sequencing (WES), RNAseq, and histologic assessment of primary and metastatic tumors from PM patients were conducted. Results: 31 RCC patients with PM were identified. We observed remarkably favorable outcomes in our PM cohort, with a median overall survival (OS) of 10.7 years from metastatic diagnosis and a long latency between initial diagnosis and development of metastasis (median 69 months in patients who were non-metastatic at diagnosis). OS was independent of both metastatic tumor burden and known IMDC prognostic factors. We discovered that tumors from PM patients were markedly uniform and clustered together by gene expression analysis. WES and DNA copy number analyses revealed a high frequency of VHL and PBRM1 mutations, 3p loss, and 5q amplification, along with a lower frequency of 9p, 14q and 4q losses and BAP1 mutations, characteristic of indolent ccRCC. Furthermore, the genomic and histologic features of tumors from patients with PM can be recapitulated in patient-derived xenograft models. Conclusions: To our knowledge, this is the first report to unravel molecular determinants of organotropism, and we highlight that organotropism can be an independent prognostic factor. Understanding tumor heterogeneity may help refine prognostic models for metastatic RCC and hold implications for improved personalization of therapy.

The role of architectural patterns and cytologic features in the prognosis of clear cell renal cell carcinoma

632

Background: Clear cell renal cell carcinoma (ccRCC) exhibits a spectrum of clinical behavior and intratumoral heterogeneity histologically. Pathologic grading for ccRCC is primarily based on nucleolar size. Sarcomatoid and rhabdoid changes are known to be associated with aggressive behavior, the significance of the histopathologic heterogeneity occurring in ccRCC remains largely unknown. We evaluated the prognostic role of architectural patterns and cytologic features in ccRCC. Methods: We identified sequential ccRCC cases at our institution between 2006 and 2015 for which follow-up information was available beyond 1.5 years, excepting those who died sooner. Architectural patterns and cytologic features were predefined and quantitated in nephrectomy specimen slides, which were reviewed by an experienced GU pathologist. Nine novel architectural patterns and ten cytologic features were correlated with disease-free survival (DFS) and overall survival (OS). Kaplan-Meier curves were generated to visualize survival distributions. Results: 549 cases met selection criteria and were comprehensively reviewed including 16 grade 1 (2.9%), 278 grade 2 (50.6%), 201 grade 3 (36.6%) and 54 grade 4 (9.8%). Pathologic tumor stage distribution included 63.9% pT1 (n = 351), 6.0% pT2 (n = 33), 27.5% pT3 (n = 151), and 2.6% pT4 (n = 14). Microcystic, tubular, bleeding follicles, and small compact nest patterns (n = 309), were associated with better DFS and OS. In contrast, large nests, thick trabecular, solid sheet, alveolar or papillary/pseudopapillary patterns (n = 240) were associated with worse DFS and OS (p < 0.0001). In addition to multinucleated giant cells, and sarcomatoid and rhabdoid changes, cytologic features including large intracytoplasmic eosinophilic inclusions, voluminous cytoplasm, cytoplasmic spindling, a giant nucleus with perinuclear halo, and a wrinkled nucleus with perinuclear halo were associated with worse DFS and OS (p < 0.0004). Conclusions: Architectural patterns and cytologic features observed in ccRCC predict tumor behavior and are associated with clinical prognosis. Evaluation of histopathologic heterogeneity may shed light on tumor biology and complement prognostic models.

Leveraging a robust patient-derived xenograft platform to characterize predictors for engraftment and oncologic outcomes in renal cell carcinoma patients

651

Background: Patient-derived xenograft (PDX) models of renal cell carcinoma (RCC) preserve the biological features of patient tumors, providing a platform for biomarker identification and preclinical drug testing. We sought to identify predictors of successful tumor engraftment and evaluate the prognostic value of engraftment in patients with RCC using a robust murine PDX platform. Methods: 1,200 specimens derived from nephrectomy, thrombectomy, metastasectomy, or biopsy were orthotopically (renally) implanted into NOD/SCID mice between 2008-2018. Non-RCC pathology was excluded. Stable engraftment was defined by successful passage of tumor tissue at least twice with histologic confirmation. Clinicopathologic characteristics were stratified by engraftment status, and multivariate (MVA) logistic regression was used to identify predictors of engraftment. Kaplan-Meier and Cox regression analyses were used to assess the prognostic value of engraftment on patient overall (OS) and disease-free (DFS) survival. Results: 1,003 independent PDX lines derived from 770 RCC patients were included. 157 (15.6%) lines successfully engrafted and exhibited higher tumor grade, stage, size, and presence of sarcomatoid or rhabdoid components. Whole exome sequencing was performed on 230 PDX lines. On MVA, sarcomatoid (OR 5.71, p < 0.001), rhabdoid (OR 2.79, p = 0.046), and advanced stage (OR 1.72, p = 0.049) were significant predictors for engraftment, while high grade and metastatic tumor source were significant only on UVA. Engraftment was associated with poor OS (HR 2.11, p < 0.001) and DFS (HR 1.85, p = 0.020) in patients after controlling for sarcomatoid, rhabdoid, grade, stage, and age on MVA. Conclusions: Aggressive RCC biology correlates with successful engraftment in PDX models. Engraftment remains independently predictive of OS and DFS even after controlling for adverse pathologic features. Engraftment in mice may illuminate aspects of tumor biology not captured by clinicopathologic variables and provide insight into novel determinants of tumor aggressiveness and metastasis. Efforts are underway to elucidate genomic drivers of engraftment.

Comprehensive molecular and genomic characterization of pancreatic tropism in metastatic renal cell carcinoma

633

Background: Patients with metastatic renal cell carcinoma (mRCC) involving the pancreas have been shown to exhibit a relatively indolent course, yet the biologic explanation is unclear. We sought to characterize the genomic landscape of patients with mRCC harboring pancreatic metastases to identify molecular drivers of pancreatic tropism. Methods: mRCC patients harboring pancreatic metastases from UTSW and Cleveland Clinic were identified. Clinicopathologic data and oncologic outcomes were analyzed. Samples were obtained from primary tumors, metastatic sites (including pancreatic or other distant metastases), and matched normal tissue. Whole exome (WES) and RNA sequencing of tumors was conducted. Patient-derived xenograft (PDX) models were generated from a subset of patients, and the engrafted tumors were analyzed. Results: 31 mRCC patients with pancreatic metastases were included with 54 tumor samples derived from the primary tumor or thrombus (24), pancreatic metastasis (21), or other metastatic sites (9). Median follow-up was 101 months. Clinicopathologic characteristics were similar between the two institutional cohorts, and all but one patient were favorable or intermediate IMDC risk. All patients had clear cell histology. 8 patients (26%) were metastatic at diagnosis, and median time to metastasis in the remaining patients was 74 months (IQR 32-120). Overall (OS) and cancer-specific (CSS) survival did not vary by IMDC risk group. Morphologically, tumors largely displayed low-grade acinar patterns. WES with matched normal tissue and RNAseq were completed with adequate quality for 48 and 30 samples, respectively. 14 PDX lines were generated, of which 5 (36%) engrafted stably (≥2 passages). WES from 2 tumorgraft specimens revealed preservation of specific mutations in the corresponding human samples. Conclusions: mRCC patients with pancreatic metastases exhibit remarkably favorable survival outcomes. The relatively indolent biology of these tumors is reflected histologically and genomically and can be recapitulated in PDX models. Understanding tumor heterogeneity may help refine prognostic models for mRCC and hold implications for improved personalization of therapy.

Delusion proneness and 'jumping to conclusions': relative and absolute effects

BACKGROUND

That delusional and delusion-prone individuals 'jump to conclusions' is one of the most robust and important findings in the literature on delusions. However, although the notion of 'jumping to conclusions' (JTC) implies gathering insufficient evidence and reaching premature decisions, previous studies have not investigated whether the evidence gathering of delusion-prone individuals is, in fact, suboptimal. The standard JTC effect is a relative effect but using relative comparisons to substantiate absolute claims is problematic. In this study we investigated whether delusion-prone participants jump to conclusions in both a relative and an absolute sense.

METHOD

Healthy participants (n = 112) completed an incentivized probabilistic reasoning task in which correct decisions were rewarded and additional information could be requested for a small price. This combination of rewards and costs generated optimal decision points. Participants also completed measures of delusion proneness, intelligence and risk aversion.

RESULTS

Replicating the standard relative finding, we found that delusion proneness significantly predicted task decisions, such that the more delusion prone the participants were, the earlier they decided. This finding was robust when accounting for the effects of risk aversion and intelligence. Importantly, high-delusion-prone participants also decided in advance of an objective rational optimum, gathering fewer data than would have maximized their expected payoff. Surprisingly, we found that even low-delusion-prone participants jumped to conclusions in this absolute sense.

CONCLUSIONS

Our findings support and clarify the claim that delusion formation is associated with a tendency to 'jump to conclusions'. In short, most people jump to conclusions, but more delusion-prone individuals 'jump further'.

Infliximab reverses inflammatory muscle wasting (sarcopenia) in Crohn's disease

BACKGROUND

Muscle wasting or sarcopenia arising from chronic inflammation is found in 60% of patients with Crohn's disease. Transcriptional protein NF-κB reduces muscle formation through MyoD transcription and increases muscle breakdown by proteolysis.

AIM

As TNF is a potent activator of NF-κB, and anti-TNF agent infliximab (IFX) prevents NF-κB activation, to determine whether or not Crohn's patients treated with IFX gain muscle volume and strength.

METHODS

We performed a prospective, repeated-measures cohort study in adult Crohn's disease patients with an acute disease flare. Patients were instructed not to vary diet or activity. Concomitant medications were kept stable. At week 1 (pre-treatment), week 16 (post-IFX induction) and week 25 (post-first IFX maintenance dose), we assessed (i) MRI volume of quadriceps femoris at anatomical mid-thigh; (ii) maximal concentric quadriceps contractions strength at three specific speeds of contraction; (iii) physical activity by validated instrument (IPAQ); (iv) Three-day food record of intake and composition (food-weighing method); (v) Serum levels of IL6.

RESULTS

Nineteen patients (58% female; mean age 33.2 ± 10.7 years) were recruited. IFX increased muscle volume in both legs from baseline (right, 1505 cm(3) ) to week 25 (right, 1569 cm(3) ; P = 0.010). IFX also increased muscle strength in both legs from baseline (right 30°/s, 184.8 Nm) to week 25 (right 30°/s, 213.6 Nm; P = 0.002). Muscle volume gain correlated with male gender (P = 0.003). Significant gains in muscle volume and strength were unrelated to prednisolone use. Serum IL6 levels decreased by week 25 (P = 0.037).

CONCLUSION

The anti-TNF agent infliximab reverses inflammatory sarcopenia in patients with Crohn's disease.

Adipose is a conserved dosage-sensitive antiobesity gene

Adipose (Adp) is an evolutionarily conserved gene isolated from naturally occurring obese flies homozygous for an adp mutation. Here we show that the anti-obesity function of Adp (worm Y73E7A.9, fly adp, and murine Wdtc1) is conserved from worms to mammals. Further, Adp appears to inhibit fat formation in a dosage-sensitive manner. Adp heterozygous flies and Adp heterozygous mutant mice are obese and insulin resistant, as are mice that express a dominant negative form of Adp in fat cells. Conversely, fat-restricted Adp transgenic mice are lean and display improved metabolic profiles. A transient transgenic increase in Adp activity in adult fly fat tissues reduces fat accumulation, indicating therapeutic potential. ADP may elicit these anti-adipogenic functions by regulating chromatin dynamics and gene transcription, as it binds both histones and HDAC3 and inhibits PPARgamma activity. Thus Adp appears to be involved in an ancient pathway that regulates fat accumulation.

Directed differentiation of human embryonic stem cells towards a pancreatic cell fate

AIMS/HYPOTHESIS

The relative lack of successful pancreatic differentiation of human embryonic stem cells (hESCs) may suggest that directed differentiation of hESCs into definitive endoderm and subsequent commitment towards a pancreatic fate are not readily achieved. The aim of this study was to investigate whether sequential exposure of hESCs to epigenetic signals that mimic in vivo pancreatic development can efficiently generate pancreatic endodermal cells, and whether these cells can be further matured and reverse hyperglycaemia upon transplantation.

MATERIALS AND METHODS

The hESCs were sequentially treated with serum, activin and retinoic acid (RA) during embryoid body formation. The patterns of gene expression and protein production associated with embryonic germ layers and pancreatic endoderm were analysed by RT-PCR and immunostaining. The developmental competence and function of hESC-derived PDX1-positive cells were evaluated after in vivo transplantation.

RESULTS

Sequential treatment with serum, activin and RA highly upregulated the expression of the genes encoding forkhead box protein A2 (FOXA2), SRY-box containing gene 17 (SOX17), pancreatic and duodenal homeobox 1 (PDX1) and homeobox HB9 (HLXB9). The population of pancreatic endodermal cells that produced PDX1 was significantly increased at the expense of ectodermal differentiation, and a subset of the PDX1-positive cells also produced FOXA2, caudal-type homeobox transcription factor 2 (CDX2), and nestin (NES). After transplantation, the PDX1-positive cells further differentiated into mature cell types producing insulin and glucagon, resulting in amelioration of hyperglycaemia and weight loss in streptozotocin-treated diabetic mice.

CONCLUSIONS/INTERPRETATION

Our strategy allows the progressive differentiation of hESCs into pancreatic endoderm capable of generating mature pancreatic cell types that function in vivo. These findings may establish the basis of further investigations for the purification of transplantable islet progenitors derived from hESCs.

Hedgehog signaling plays a conserved role in inhibiting fat formation

Hedgehog (Hh) signals regulate invertebrate and vertebrate development, yet the role of the cascade in adipose development was undefined. To analyze a potential function, we turned to Drosophila and mammalian models. Fat-body-specific transgenic activation of Hh signaling inhibits fly fat formation. Conversely, fat-body-specific Hh blockade stimulated fly fat formation. In mammalian models, sufficiency and necessity tests showed that Hh signaling also inhibits mammalian adipogenesis. Hh signals elicit this function early in adipogenesis, upstream of PPARgamma, potentially diverting preadipocytes as well as multipotent mesenchymal prescursors away from adipogenesis and toward osteogenesis. Hh may elicit these effects by inducing the expression of antiadipogenic transcription factors such as Gata2. These data support the notion that Hh signaling plays a conserved role, from invertebrates to vertebrates, in inhibiting fat formation and highlighting the potential of the Hh pathway as a therapeutic target for osteoporosis, lipodystrophy, diabetes, and obesity.

Attractiveness of facial averageness and symmetry in non-western cultures: in search of biologically based standards of beauty

Averageness and symmetry are attractive in Western faces and are good candidates for biologically based standards of beauty. A hallmark of such standards is that they are shared across cultures. We examined whether facial averageness and symmetry are attractive in non-Western cultures. Increasing the averageness of individual faces, by warping those faces towards an averaged composite of the same race and sex, increased the attractiveness of both Chinese (experiment 1) and Japanese (experiment 2) faces, for Chinese and Japanese participants, respectively. Decreasing averageness by moving the faces away from an average shape decreased attractiveness. We also manipulated the symmetry of Japanese faces by blending each original face with its mirror image to create perfectly symmetric versions. Japanese raters preferred the perfectly symmetric versions to the original faces (experiment 2). These findings show that preferences for facial averageness and symmetry are not restricted to Western cultures, consistent with the view that they are biologically based. Interestingly, it made little difference whether averageness was manipulated by using own-race or other-race averaged composites and there was no preference for own-race averaged composites over other-race or mixed-race composites (experiment 1). We discuss the implications of these results for understanding what makes average faces attractive. We also discuss some limitations of our studies, and consider other lines of converging evidence that may help determine whether preferences for average and symmetric faces are biologically based.

Changes in management of diabetic retinopathy by Australian ophthalmologists as a result of the NHMRC clinical guidelines

PURPOSE

To document changes in management of diabetic retinopathy by Australian ophthalmologists after release of the National Health and Medical Research Council (NHMRC) clinical guidelines.

METHODS

Self-administered questionnaires were mailed to Australian ophthalmologists prior to release of the NHMRC guidelines for the management of diabetic retinopathy, and at one and 2.5 years after release of the guidelines. The questionnaires elicited information about current management practices in relation to diabetic retinopathy

RESULTS

The response rate for the baseline and two follow-up surveys was 82%, 81%, and 80%, respectively. More than 85% of the ophthalmologists responded that the guidelines were useful in improving management, were easy to understand, and were already part of their routine clinical practice. A relatively small percentage (12%) felt that the guidelines made recommendations that were not practical or feasible. Contrary to the NHMRC guidelines, at the second follow-up survey, only 50% of the ophthalmologists said that they would almost never perform fluorescein angiography in eyes with mild non-proliferative diabetic retinopathy. The change from baseline to the second follow-up in the percentage of ophthalmologists who would perform cataract surgery after treating clinically significant macular oedema (as advised by the NHMRC guidelines) was statistically significant (baseline = 83.7%, 95% confidence limit = 80.4, 87.0; second follow up = 90.4, 95% confidence limit = 87.3, 93.5).

CONCLUSIONS

Distribution of the printed NHMRC Clinical Practice Guidelines: Management of Diabetic Retinopathy and full colour Retinopathy Chart resulted in a significant change in the recommended order of treatment of clinically significant macular oedema. However no significant change in the use of fluorescein angiography was documented.

Changes in attitudes and practices of optometrists in their management of diabetic retinopathy after the release of NHMRC guidelines. National Health and Medical Research Council

The purpose of this study was to document attitudes and practices of Australian optometrists in their management of diabetic retinopathy prior to the release of the National Health and Medical Research Council (NHMRC) Clinical Practice Guidelines for the Management of Diabetic Retinopathy and at two time points following their release. A self-administered questionnaire was mailed to a stratified random sample of 500 Australian optometrists at the three time points. The same sample was used for the first two surveys and a new random sample was drawn for the second follow-up survey. The response to the three questionnaires was 86%, 80% and 84%, respectively. More than 90% of optometrists reported receiving a copy of the guidelines and 82% reported receiving the supplementary Retinopathy Chart. Fifty-seven per cent reported having read the guidelines at least once in entirety and 65% reported that they refer to the Retinopathy Chart at least monthly in their clinical practice. There was a significant decrease in the number of optometrists who reported that patient unwillingness to be dilated and their fear of precipitating angle closure glaucoma were moderate or major barriers to performing dilated ophthalmoscopy. Concomitantly, the percentage of optometrists who reported that they often or always perform dilated ophthalmoscopy on new patients with diabetes increased significantly from 74.5% (95% confidence limit = 70.2, 78.8) to 81.5% (95% confidence limit = 77.5, 85.5). There have been some significant changes in the self-reported management practices of optometrists in relation to diabetic retinopathy since the release of the NHMRC guidelines and Retinopathy Chart.

Differentiation of embryonic stem cells to insulin-secreting structures similar to pancreatic islets

Although the source of embryonic stem (ES) cells presents ethical concerns, their use may lead to many clinical benefits if differentiated cell types can be derived from them and used to assemble functional organs. In pancreas, insulin is produced and secreted by specialized structures, islets of Langerhans. Diabetes, which affects 16 million people in the United States, results from abnormal function of pancreatic islets. We have generated cells expressing insulin and other pancreatic endocrine hormones from mouse ES cells. The cells self-assemble to form three-dimensional clusters similar in topology to normal pancreatic islets where pancreatic cell types are in close association with neurons. Glucose triggers insulin release from these cell clusters by mechanisms similar to those employed in vivo. When injected into diabetic mice, the insulin-producing cells undergo rapid vascularization and maintain a clustered, islet-like organization.

Bone marrow cells regenerate infarcted myocardium

Myocardial infarction leads to loss of tissue and impairment of cardiac performance. The remaining myocytes are unable to reconstitute the necrotic tissue, and the post-infarcted heart deteriorates with time. Injury to a target organ is sensed by distant stem cells, which migrate to the site of damage and undergo alternate stem cell differentiation; these events promote structural and functional repair. This high degree of stem cell plasticity prompted us to test whether dead myocardium could be restored by transplanting bone marrow cells in infarcted mice. We sorted lineage-negative (Lin-) bone marrow cells from transgenic mice expressing enhanced green fluorescent protein by fluorescence-activated cell sorting on the basis of c-kit expression. Shortly after coronary ligation, Lin- c-kitPOS cells were injected in the contracting wall bordering the infarct. Here we report that newly formed myocardium occupied 68% of the infarcted portion of the ventricle 9 days after transplanting the bone marrow cells. The developing tissue comprised proliferating myocytes and vascular structures. Our studies indicate that locally delivered bone marrow cells can generate de novo myocardium, ameliorating the outcome of coronary artery disease.

Diabetic retinopathy: effects of national guidelines on the referral, examination and treatment practices of ophthalmologists and optometrists

OBJECTIVE

To investigate the changes in referral, examination and treatment practices for diabetic retinopathy by ophthalmologists and optometrists following the release of national guidelines.

METHODS

A two-page self-administered questionnaire was mailed to all Australian ophthalmologists and a random sample of 500 Australian optometrists prior to and 1 year after release of the National Health and Medical Research Council of Australia (NHMRC) clinical practice guidelines for the management of diabetic retinopathy. The questionnaires elicited information about current practice related to the management of patients with diabetic retinopathy.

RESULTS

Of the 464 contactable ophthalmologists who responded to the baseline survey, 374 (80.6% response) completed the follow-up survey The response rate for the contactable optometrists was 80.1% (310 of 384). There were almost no significant changes in management practices from baseline to follow up. For example, the percentage of ophthalmologists who reported that they were often or almost always confident in detecting moderate retinal thickening near the macula remained nearly identical from baseline to follow up (80.2% vs 79.1 %). The rate was also similar from baseline to follow up for optometrists (31.1% vs 28.8%). The one area in which ophthalmologists reported significant changes in management towards agreement with the NHMRC guidelines was use of angiography; they were less likely to manage their patients this way (20.4% vs 14.2% with laser and 48.9% vs 38.4% without laser for increasing level of severity in clinical signs; both P < 0.05).

CONCLUSIONS

The NHMRC guidelines for diabetic retinopathy have been successfully distributed to ophthalmologists and optometrists in Australia. However, the mere provision of the guidelines has had little impact on management practices. It will be important to determine if ongoing dissemination and implementation strategies not only increase awareness of health-care practitioners to the guidelines, but also change behaviours.

Theoretical and practical considerations in the psychological and educational assessment of the student with intractable epilepsy: dynamic assessment as an adjunct to static assessment

Assessing the student with intractable epilepsy requires skill not only in evaluating cognitive problems, but also detecting seizures and discovering how to adapt instruction to minimize their negative impact on learning. Ironically, assessment efforts are seen as compromised by the occurrence of seizures during testing, when determining how seizure events may interfere with learning and the instructional modifications that are necessary to cope with them, should be a key part of assessment. A dual approach to assessment is recommended that combines the identification of cognitive deficits with an evaluation of how recurring seizures may prevent the student from engaging in instruction. Without also evaluating the student's response to instruction, teaching to specific cognitive needs is limited by insufficient knowledge about how to keep the student involved in instruction when seizures occur. Static assessment evaluates cognitive functioning at the time of testing, without changing the way that the student learns and responds. By engaging the student in teaching/learning sessions, dynamic assessment explores how the student best learns despite cognitive deficits and the disruptive effect of seizures. This paper includes a description of the authors'experience in using dynamic assessment as an adjunct to static assessment in evaluating a student with intractable epilepsy.

Measurement of CP-violating asymmetries in B0 decays to CP eigenstates

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta = 0.34+/-0.20 (stat)+/-0.05 (syst).

Targeted genomic disruption of H-ras and N-ras, individually or in combination, reveals the dispensability of both loci for mouse growth and development

Mammalian cells harbor three highly homologous and widely expressed members of the ras family (H-ras, N-ras, and K-ras), but it remains unclear whether they play specific or overlapping cellular roles. To gain insight into such functional roles, here we generated and analyzed H-ras null mutant mice, which were then also bred with N-ras knockout animals to ascertain the viability and properties of potential double null mutations in both loci. Mating among heterozygous H-ras(+/-) mice produced H-ras(-/-) offspring with a normal Mendelian pattern of inheritance, indicating that the loss of H-ras did not interfere with embryonic and fetal viability in the uterus. Homozygous mutant H-ras(-/-) mice reached sexual maturity at the same age as their littermates, and both males and females were fertile. Characterization of lymphocyte subsets in the spleen and thymus showed no significant differences between wild-type and H-ras(-/-) mice. Analysis of neuronal markers in the brains of knockout and wild-type H-ras mice showed that disruption of this locus did not impair or alter neuronal development. Breeding between our H-ras mutant animals and previously available N-ras null mutants gave rise to viable double knockout (H-ras(-/-)/N-ras(-/-)) offspring expressing only K-ras genes which grew normally, were fertile, and did not show any obvious phenotype. Interestingly, however, lower-than-expected numbers of adult, double knockout animals were consistently obtained in Mendelian crosses between heterozygous N-ras/H-ras mice. Our results indicate that, as for N-ras, H-ras gene function is dispensable for normal mouse development, growth, fertility, and neuronal development. Additionally, of the three ras genes, K-ras appears to be not only essential but also sufficient for normal mouse development.

Do facial averageness and symmetry signal health?

We investigated whether the attractive facial traits of averageness and symmetry signal health, examining two aspects of signalling: whether these traits are perceived as healthy, and whether they provide accurate health information. In Study 1, we used morphing techniques to alter the averageness and symmetry of individual faces. Increases in both traits increased perceived health, and perceived health correlated negatively with rated distinctiveness (a converse measure of averageness) and positively with rated symmetry of the images. In Study 2, we examined whether these traits signal real, as well as perceived, health, in a sample of individuals for whom health scores, based on detailed medical records, were available. Perceived health correlated negatively with distinctiveness and asymmetry, replicating Study 1. Facial distinctiveness ratings of 17-year-olds were associated with poor childhood health in males, and poor current and adolescent health in females, although the last association was only marginally significant. Facial asymmetry of 17-year-olds was not associated with actual health. We discuss the implications of these results for a good genes account of facial preferences.

Diabetes in Victoria, Australia: the Visual Impairment Project

OBJECTIVES

To establish the prevalence and characteristics of self-reported diabetes in a representative sample of Victorian residents aged 40 years and older, and to compare the vision between people with and without self-reported diabetes.

DESIGN

Cross-sectional survey.

SETTING

Nine randomly selected suburban Melbourne clusters and four randomly selected rural Victorian clusters.

PARTICIPANTS

4,744 subjects (86% participation rate) aged > or = 40 years.

MAIN OUTCOME MEASURES

Subjects answered a detailed questionnaire which provided demographic details, body mass index, and the duration and treatment of any diagnosis of diabetes. Refraction was performed and best-corrected visual acuity was measured.

RESULTS

The prevalence of self-reported diabetes was 5.1%. In a multivariate analysis, self-reported diabetes was positively associated with age (p < 0.01), male sex (p = 0.01), higher body mass index (p = 0.01), Mediterranean ethnicity (p = 0.01), unemployment (p = 0.05) and lack of private health insurance (p < 0.05). People with self-reported diabetes were more likely to have mild or moderate levels of visual impairment than people who reported no previous diagnosis of diabetes (p < 0.01).

CONCLUSIONS

Diabetes in Victoria is more prevalent among men and among people of Mediterranean origin. When planning educational programs and health service delivery, it is also important to consider that, compared with the general population, people with diabetes are less likely to be employed or to have private health insurance, and are more likely to have impaired vision.

Enhanced proliferation, survival, and dopaminergic differentiation of CNS precursors in lowered oxygen

Standard cell culture systems impose environmental oxygen (O(2)) levels of 20%, whereas actual tissue O(2) levels in both developing and adult brain are an order of magnitude lower. To address whether proliferation and differentiation of CNS precursors in vitro are influenced by the O(2) environment, we analyzed embryonic day 12 rat mesencephalic precursor cells in traditional cultures with 20% O(2) and in lowered O(2) (3 +/- 2%). Proliferation was promoted and apoptosis was reduced when cells were grown in lowered O(2), yielding greater numbers of precursors. The differentiation of precursor cells into neurons with specific neurotransmitter phenotypes was also significantly altered. The percentage of neurons of dopaminergic phenotype increased to 56% in lowered O(2) compared with 18% in 20% O(2). Together, the increases in total cell number and percentage of dopaminergic neurons resulted in a ninefold net increase in dopamine neuron yield. Differential gene expression analysis revealed more abundant messages for FGF8, engrailed-1, and erythropoietin in lowered O(2). Erythropoietin supplementation of 20% O(2) cultures partially mimicked increased dopaminergic differentiation characteristic of CNS precursors cultured in lowered O(2). These data demonstrate increased proliferation, reduced cell death, and enhanced dopamine neuron generation in lowered O(2), making this method an important advance in the ex vivo generation of specific neurons for brain repair.

Diabetic retinopathy in Victoria, Australia: the Visual Impairment Project

AIM

To establish the prevalence, severity, and risk factors for diabetic retinopathy in a representative sample of Victorian residents aged 40 years and older.

METHODS

A population based, cluster sampling method was used to recruit 4744 participants (86% participation rate). Nine randomly selected, suburban Melbourne clusters and four randomly selected, rural Victorian clusters were used. Participants provided a detailed medical and personal history and underwent an ocular examination including funduscopy and fundus photography. Rural participants provided a blood sample, from which the glycosylated haemoglobin percentage was measured. The diagnosis of diabetic retinopathy was based on fundus photographs from participants with self reported diabetes.

RESULTS

The prevalence of diabetic retinopathy among people with self reported diabetes was 29. 1%. The prevalence of untreated, vision threatening retinopathy was 2.8%. Retinopathy was positively associated with a longer reported duration of diabetes diagnosis (p<0.01) and with higher fractions of glycosylated haemoglobin (p<0.01). Retinopathy was not significantly associated with age, ethnicity, body mass index, glaucoma, myopia or intake of alcohol, tobacco, or aspirin (all p > 0.05).

CONCLUSIONS

Most people in Victoria with proliferative diabetic retinopathy or clinically significant macular oedema have received laser treatment. There remains however, a small but important group who have not received treatment and whose vision is threatened. People with diabetes should be encouraged to maintain strict glycaemic control and to undergo regular screening to delay or prevent the development of retinopathy.

Management of diabetic retinopathy by Australian ophthalmologists. Working Group on Evaluation of the NHMRC Retinopathy Guideline Distribution. National Health and Medical Research Council

OBJECTIVE

To describe current management practices of diabetic retinopathy used by Australian ophthalmologists.

SETTING

Two-page self-administered questionnaire mailed to 622 ophthalmologists listed with the Royal Australian College of Ophthalmologists.

METHODS

The survey included questions about practice details such as size and location; specialty; current practice with regard to management of patients with diabetes; confidence in screening for diabetic retinopathy; and a number of patient scenarios related to screening, follow-up and treatment of diabetic retinopathy.

RESULTS

Of the 577 eligible ophthalmologists, 475 (82%) completed the questionnaire. They had been practicing ophthalmology between 1 and 50 years (median 16 years) and 89 (19%) indicated that they had a subspecialty interest either in vitreo-retinal surgery or in medical retina. For 145 (30.5%) of the ophthalmologists, at least one of their practices was located in a country area. The estimated percentage of patients with diabetes ranged from 0.1 to 60% (mean = 9.9%). Retinal specialists perform between 0 and 750 macular focal photocoagulation procedures per year (mean = 94) compared with a range of 0-350 for nonretinal specialists (mean = 10.3) (t = 6.1, P < 0.001). The ophthalmologists were presented with a hypothetical patient with cataract requiring surgery and clinically significant macular oedema that would be difficult to treat (but not impossible) because of the cataract. Seventy-seven ophthalmologists (16%) said they would delay the macular laser therapy until after the cataract surgery had been performed. In multivariate logistic regression models, nonretinal specialists were 4.44 times as likely to perform the cataract surgery first (95%CL = 1.57, 12.6) and ophthalmologists who had been in practice more than 15 years were 2.50 times as likely to perform cataract surgery first (95%CL = 1.47, 4.26). There were other examples of practice that differed from the National Health and Medical Research Council (NHMRC) guidelines in patient scenarios. The majority of ophthalmologists (60%) expressed a moderate or strong need to learn more about the management of diabetic retinopathy.

DISCUSSION

The variability in the management of diabetic retinopathy by Australian ophthalmologists and the desire of ophthalmologists to learn more about diabetic retinopathy provide evidence to support the need for the NHMRC Guidelines for Diabetic Retinopathy. These data will be used to evaluate changes in practice as a result of the implementation of the guidelines.

Stem cells and the cellular organization of the brain

The modern field of neuroscience emerged in the hands of neuroanatomists at the end of the last century. They recognized that information flows through arrays of cells and that the structure of the cells shapes the passage of information through the brain. In the middle of this century, the role of ion flux in the movement of information along axons was established. The electron microscope and the microelectrode helped to explain information transfer at the synapse, and study of the modulation of synaptic strength is currently a major area of neuroscience research. The origin of the many types of neuron seen by the early anatomists remains enigmatic, but the solution to this mystery is now emerging. The identification of stem cells and of the mechanisms that control their differentiation into distinct neuron types will contribute to a new understanding of both the origin of neuronal types and neuronal circuits. The current enthusiasm for stem cells is stimulated by interest from both the academic and nonacademic communities. These enthusiasts recognize a simple truth, that the cells are smart; they are the agents that control cell number and type in the brain. They create the structure that generates the higher order brain function. If these premises are true, then in the new century our understanding of the nervous system will be transformed by the facts of stem cell biology. J. Neurosci. Res. 59:298-300, 2000. Published 2000 Wiley-Liss, Inc.

Management of diabetic retinopathy by Australian optometrists. Working Group on Evaluation of NHMRC Retinopathy Guideline Distribution. National Health and Medical Research Council

PURPOSE

To describe current practices related to the management of diabetic retinopathy by Australian optometrists.

SETTING AND METHODS

A two-page self-administered questionnaire was mailed to a random sample of 504 Australian optometrists. The survey included questions about the practice (such as size and location); current practice with regard to management of patients with diabetic retinopathy; barriers to use of dilating drops; and a number of patient scenarios related to screening, follow-up and treatment of diabetic retinopathy.

RESULTS

Completed questionnaires were returned by 407 of the 473 eligible optometrists (86%). They had been practising optometry between 1 and 50 years (median 14). Of the 243 optometrists who provided details about the location of their practices, 145 (37%) had at least one of their practices in a rural area. The estimated percentage of patients with diagnosed diabetes ranged from 0.5 to 40% (median = 5.0%). Three-hundred and twenty-two optometrists (79%) reported that they would often or almost always ask new patients over the age of 40 whether they have diabetes. The majority of optometrists (n = 387, 95%) would often or almost always ask their new patients with diabetes about their control of blood glucose levels and the majority of optometrists (n = 330, 81%) would often or almost always tell their patients with diabetes about the importance of strict glucose control in delaying retinopathy. The most common barrier to dilated ophthalmoscopy was patients not wanting to be dilated, with 38.1% of optometrists reporting this to be a moderate or major barrier. The next most common barrier was fear of precipitating angle closure glaucoma; 17.1% of optometrists reported this to be a moderate or major barrier

CONCLUSION

The National Health and Medical Research Council (NHMRC) guidelines for the management of diabetic retinopathy are timely in relation to the expressed desire of Australian optometrists to learn more about management of diabetic retinopathy These data will be used prospectively to assess changes in management of patients with diabetic retinopathy as a result of the release of the NHMRC guidelines.