NIR Spectroscopy as an Online PAT Tool for a Narrow Therapeutic Index Drug: Toward a Platform Approach Across Lab and Pilot Scales for Development of a Powder Blending Monitoring Method and Endpoint Determination

An online near-infrared (NIR) spectroscopy platform system for real-time powder blending monitoring and blend endpoint determination was tested for a phenytoin sodium formulation. The study utilized robust experimental design and multiple sensors to investigate multivariate data acquisition, model development, and model scale-up from lab to manufacturing. The impact of the selection of various blend endpoint algorithms on predicted blend endpoint (i.e., mixing time) was explored. Spectral data collected at two process scales using two NIR spectrometers was incorporated in a single (global) calibration model. Unique endpoints were obtained with different algorithms based on standard deviation, average, and distributions of concentration prediction for major components of the formulation. Control over phenytoin sodium's distribution was considered critical due to its narrow therapeutic index nature. It was found that algorithms sensitive to deviation from target concentration offered the simplest interpretation and consistent trends. In contrast, algorithms sensitive to global homogeneity of active and excipients yielded the longest mixing time to achieve blending endpoint. However, they were potentially more sensitive to subtle uniformity variations. Qualitative algorithms using principal component analysis (PCA) of spectral data yielded the prediction of shortest mixing time for blending endpoint. The hybrid approach of combining NIR data from different scales presents several advantages. It enables simplifying the chemometrics model building process and reduces the cost of model building compared to the approach of using data solely from commercial scale. Success of such a hybrid approach depends on the spectroscopic variability captured at different scales and their relative contributions in the final NIR model.

Abstract PO-073: Inactivation of Notch4 attenuated pancreatic tumorigenesis in mice

Expression of the Notch family of receptors are often upregulated in pancreatic ductal adenocarcinoma (PDAC), however, the functional impacts of the Notch signaling network on pancreatic tumorigenesis remain unresolved. In this study, we focused on Notch4, which had not been investigated in PDAC. Leveraging the conventional Notch4 deficient mouse line and previously established genetically engineered mouse models (GEMM) for PDAC, we generated KC (LSL-KrasG12D;p48-Cre), N4−/−KC (Notch4−/−;LSL-KrasG12D;p48-Cre), PKC (p16flox/flox;LSL-KrasG12D;p48-Cre), and N4−/−PKC GEMMs (Notch4−/−; p16flox/lox;LSL-KrasG12D;p48-Cre). We performed caerulein treatment in both KC and N4−/−KC mice, and compared the development of acinar to ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) between them. The ADM/PanIN lesions were significantly smaller in the N4−/−KC than in the KC GEMM (p=0.01), suggesting that Notch4 deficiency attenuated early pancreatic tumorigenesis. This in vivo result was confirmed by in vitro ADM induction of the explant cultures of mouse pancreatic acinar cells. The number of ADM structures in the N4−/−KC acinar cultures was significantly lower than the KC acinar cultures (p<0.001). To evaluate the role of Notch4 in the later stage of pancreatic tumorigenesis, we compared the histological progression and overall survival between the PKC and N4−/−PKC mice. We found that N4−/−PKC mice had better prognosis (p=0.012) and less tumor burden (PanIN: p=0.018 (2 months), PDAC: p=0.039 (5 months)) compared to the PKC GEMM. RNA-Seq analysis of pancreatic tumor cell lines derived from the PKC and N4−/−PKC GEMMs revealed 408 genes were differentially expressed (FDR<0.05) and the genes related to the NGF processing as novel downstream effectors of the Notch4 signaling pathway(p<0.001). Our study is a novel biological investigation that demonstrated that Notch4 signaling possesses tumor promoting function in pancreatic tumorigenesis. Our study revealed a novel association between the NGF processing pathway and Notch4 signaling in PDAC.

Citation Format: Kiyoshi Saeki, Wanglong Qiu, Richard Friedman, Carrie Shawber, Jan Kitajewski, Jianhua Hu, Gloria H. Su. Inactivation of Notch4 attenuated pancreatic tumorigenesis in mice [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2021 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2021;81(22 Suppl):Abstract nr PO-073.

Anatomical and reverse shoulder arthroplasty utilizing a single implant system with a platform stem: A prospective observational study with midterm follow-up

BACKGROUND

No studies compare outcomes of anatomic total shoulder arthroplasty to reverse total shoulder arthroplasty with more than five-year follow-up.

METHODS

A multicenter prospectively collected shoulder registry was utilized to review all patients undergoing primary anatomic total shoulder arthroplasty or primary reverse total shoulder arthroplasty with a minimum five-year follow-up utilizing a single platform stem implant system. One-hundred-ninety-one patients received an anatomic total shoulder arthroplasty and 139 patients received a reverse total shoulder arthroplasty. Patients were scored preoperatively and at latest follow-up using the simple shoulder test (SST), University of California Los Angeles (UCLA), American shoulder and elbow surgeons (ASES), Constant, and shoulder pain and disability index (SADI) scores as well as range of motion. Radiographs were evaluated for implant loosening or notching. Complications were reviewed. A Student's two-tailed, unpaired t-test identified differences in preoperative, postoperative, and pre-to-postoperative improvements.

RESULTS

Reverse total shoulder arthroplasty patients were significantly older than anatomic total shoulder arthroplasty patients. All patients demonstrated significant improvement in functional metric scores and range of motion following anatomic total shoulder arthroplasty or reverse total shoulder arthroplasty. There was no difference in final outcome scores between anatomic total shoulder arthroplasty and reverse total shoulder arthroplasty patients at midterm follow-up; however, reverse total shoulder arthroplasty patients demonstrated significantly less motion.

DISCUSSION

We demonstrate equivalent outcomes with five scoring metrics at mean follow-up of 71.3 ± 14.1 months. Although postoperative scores were significantly greater than preoperative scores for both anatomic total shoulder arthroplasty and reverse total shoulder arthroplasty patients, significant differences in outcome scores between cohorts were not observed.

The modern reverse shoulder arthroplasty and an updated systematic review for each complication: part II

Background

Globally, reverse shoulder arthroplasty (RSA) has moved away from the Grammont design to modern prosthesis designs. The purpose of this study was to provide a focused, updated systematic review for each of the most common complications of RSA by limiting each search to publications after 2010. In this part II, the following were examined: (1) instability, (2) humerus/glenoid fracture, (3) acromial/scapular spine fractures (AF/SSF), and (4) problems/miscellaneous.

Methods

Four separate PubMed database searches were performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Overall, 137 studies for instability, 94 for humerus/glenoid fracture, 120 for AF/SSF, and 74 for problems/miscellaneous were included in each review, respectively. Univariate analysis was performed with chi-square and Fisher exact tests.

Results

The Grammont design had a higher instability rate vs. all other designs combined (4.0%, 1.3%; P < .001), and the onlay humerus design had a lower rate than the lateralized glenoid design (0.9%, 2.0%; P = .02). The rate for intraoperative humerus fracture was 1.8%; intraoperative glenoid fracture, 0.3%; postoperative humerus fracture, 1.2%; and postoperative glenoid fracture, 0.1%. The rate of AF/SSF was 2.6% (371/14235). The rate for complex regional pain syndrome was 0.4%; deltoid injury, 0.1%; hematoma, 0.3%; and heterotopic ossification, 0.8%.

Conclusions

Focused systematic reviews of recent literature with a large volume of shoulders demonstrate that using non-Grammont modern prosthesis designs, complications including instability, intraoperative humerus and glenoid fractures, and hematoma are significantly reduced compared with previous studies. As the indications continue to expand for RSA, it is imperative to accurately track the rate and types of complications in order to justify its cost and increased indications.

The modern reverse shoulder arthroplasty and an updated systematic review for each complication: part I

Background

Globally, reverse shoulder arthroplasty (RSA) has moved away from the Grammont design to modern prosthesis designs. The purpose of this 2-part study was to systematically review each of the most common complications of RSA, limiting each search to publications in 2010 or later. In this part (part I), we examined (1) scapular notching (SN), (2) periprosthetic infection (PJI), (3) mechanical failure (glenoid or humeral component), and (4) neurologic injury (NI).

Methods

Four separate PubMed database searches were performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Overall, 113 studies on SN, 62 on PJI, 34 on mechanical failure, and 48 on NI were included in our reviews. Univariate analysis was performed with the χ² or Fisher exact test.

Results

The Grammont design had a higher SN rate vs. all other designs combined (42.5% vs. 12.3%, P < .001). The onlay humeral design had a lower rate than the lateralized glenoid design (10.5% vs. 14.8%, P < .001). The PJI rate was 2.4% for primary RSA and 2.6% for revision RSA. The incidence of glenoid and humeral component loosening was 2.3% and 1.4%, respectively. The Grammont design had an increased NI rate vs. all other designs combined (0.9% vs. 0.1%, P = .04).

Conclusions

Focused systematic reviews of the recent literature with a large volume of RSAs demonstrate that with the use of non-Grammont modern prosthesis designs, complications including SN, PJI, glenoid component loosening, and NI are significantly reduced compared with previous studies. As the indications for RSA continue to expand, it is imperative to accurately track the rates and types of complications to justify its cost and increased indications.

Chronic rhinitis in South Africa - more than just allergy!

Chronic rhinitis is a troublesome condition for sufferers. It is tempting to label all patients with chronic nasal symptoms as having allergic rhinitis (AR), but many such patients have other causes of chronic rhinitis that need a specific diagnosis and management strategy. Even when the patient fully fits the definition of AR, their condition will be best served by combining medication with ongoing patient education.

Abstract I17: Genomic loss of the wild-type KRAS allele in pancreatic tumor progression and metastasis

KRAS is a major oncogenic driver in pancreatic ductal adenocarcinoma (PDAC). Intriguingly, human tumors with RAS mutations often display loss of the remaining wild-type (WT) allele, including PDAC. We previously reported that selective loss of WT Kras allele is associated with PDAC progression to metastasis in both mice and humans. These data suggest that WT KRAS functions as a tumor suppressor in the context of mutant KRAS and loss of WT KRAS offers growth advantage in clonal evolution and tumor progression to metastasis. To investigate the underlying mechanism, we have examined the impact of inducible WT KRAS expression on human PDAC cell lines that had spontaneously lost the WT allele. We observed re-expression of WT KRAS significantly attenuated the malignancy of pancreatic cancer cells in vitro and in vivo. RNA-Seq and proteomic analyses identified HIPPO signaling, specifically YAP1 activation, is inhibited by WT KRAS restoration. We observed a marked reduction of YAP1 nuclear localization and a consequent inhibition of YAP1 transcriptional activity upon restoration of WT KRAS. Expression of constitutively activated YAP1 mitigated the growth-inhibitory effects of WT KRAS, confirming that YAP1 is a downstream effector of the pathway. Furthermore, YAP1 nuclear localization was found to be associated with poor prognosis in PDAC patients. Together, these results offer a novel mechanism that WT KRAS suppresses tumor metastasis via inhibition of YAP1 activation and further demonstrate that genomic loss of the WT KRAS allele is not a mere consequence of genomic instability but rather a selective event that promotes pancreatic tumor progression to metastasis.

Citation Format: Han Yan, Chih-Chieh Yu, Stuart Fine, Ayman Lee, Ye-Ran Yang, Juan Yan, Dario Garcia-Carracedo, Dillon Karg, Edwin Cheung, Richard Friedman, Emily Chen, Ji Luo, Yi Miao, Wanglong Qiu, Gloria Su. Genomic loss of the wild-type KRAS allele in pancreatic tumor progression and metastasis [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr I17.

High-Fat Diet Accelerates Carcinogenesis in a Mouse Model of Barrett's Esophagus via Interleukin 8 and Alterations to the Gut Microbiome

BACKGROUND & AIMS

Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma (EAC). Progression from BE to cancer is associated with obesity, possibly due to increased abdominal pressure and gastroesophageal reflux disease, although this pathogenic mechanism has not been proven. We investigated whether environmental or dietary factors associated with obesity contribute to the progression of BE to EAC in mice.

METHODS

Tg(ED-L2-IL1RN/IL1B)#Tcw mice (a model of BE, called L2-IL1B mice) were fed a chow (control) or high-fat diet (HFD) or were crossbred with mice that express human interleukin (IL) 8 (L2-IL1B/IL8 mice). Esophageal tissues were collected and analyzed for gene expression profiles and by quantitative polymerase chain reaction, immunohistochemistry, and flow cytometry. Organoids were established from BE tissue of mice and cultured with serum from lean or obese individuals or with neutrophils from L2-IL1B mice. Feces from mice were analyzed by 16s ribosomal RNA sequencing and compared to 16s sequencing data from patients with dysplasia or BE. L2-IL1B were mice raised in germ-free conditions.

RESULTS

L2-IL1B mice fed an HFD developed esophageal dysplasia and tumors more rapidly than mice fed the control diet; the speed of tumor development was independent of body weight. The acceleration of dysplasia by the HFD in the L2-IL1B mice was associated with a shift in the gut microbiota and an increased ratio of neutrophils to natural killer cells in esophageal tissues compared with mice fed a control diet. We observed similar differences in the microbiomes from patients with BE that progressed to EAC vs patients with BE that did not develop into cancer. Tissues from dysplasias of L2-IL1B mice fed the HFD contained increased levels of cytokines that are produced in response to CXCL1 (the functional mouse homolog of IL8, also called KC). Serum from obese patients caused organoids from L2-IL1B/IL8 mice to produce IL8. BE tissues from L2-IL1B mice fed the HFD and from L2-IL1B/IL8 mice contained increased numbers of myeloid cells and cells expressing Cxcr2 and Lgr5 messenger RNAs (epithelial progenitors) compared with mice fed control diets. BE tissues from L2-IL1B mice raised in germ-free housing had fewer progenitor cells and developed less dysplasia than in L2-IL1 mice raised under standard conditions; exposure of fecal microbiota from L2-IL1B mice fed the HFD to L2-IL1B mice fed the control diet accelerated tumor development.

CONCLUSIONS

In a mouse model of BE, we found that an HFD promoted dysplasia by altering the esophageal microenvironment and gut microbiome, thereby inducing inflammation and stem cell expansion, independent of obesity.

Resurfaced versus Non-Resurfaced Patella in Total Knee Arthroplasty

The prevalence of knee osteoarthritis is increasing, as is the projected use of total knee arthroplasty (TKA) to treat severe cases that fail to respond to conservative measures. Implant designs are either cruciate retaining or posterior stabilized, and while both have high success rates, management of the patella still remains a controversial topic. Although studies indicate that resurfacing the patella provides no significant clinical differences compared with non-resurfacing techniques, surgeons continue to resurface the patella during TKA. Rates of patella resurfacing continue to be as high as 90% in the United States, while European countries tend to favor non-resurfacing techniques. The purpose of this article is to discuss relevant research on patella resurfacing during TKA, to compare the results, and give evidence-based recommendations on how it should be approached going forward.

Evaluating Glenohumeral Osteoarthritis: The Relative Impact of Patient Age, Activity Level, Symptoms, and Kellgren-Lawrence Grade on Treatment

BACKGROUND

It is not always clear how to treat glenohumeral osteoarthritis, particularly in young patients. The goals of this study were to 1) quantify how patient age, activity level, symptoms, and radiographic findings impact the decision-making of shoulder specialists and 2) evaluate the observer reliability of the Kellgren-Lawrence (KL) grading system for primary osteoarthritis of the shoulder.

METHODS

Twenty-six shoulder surgeons were each sent 54 simulated patient cases. Each patient had a different combination of age, symptoms, activity level, and radiographs. Responders graded the radiographs and chose a treatment (non-operative, arthroscopy, hemiarthroplasty, or total shoulder arthroplasty). Spearman correlations and chi square tests were used to assess the relationship between factors and treatments. Sub-analysis was performed on surgical cases. An intra-class correlation (ICC) was used to assess observer agreement.

RESULTS

The significant correlations (P<0.01) were: symptoms [0.46], KL grade [0.44], and age [0.11]. In the sub-analysis of operative cases, the significant correlations were: KL grade [0.64], age [0.39], and activity level [-0.10]. The chi square analysis was significant (P<0.01) for all factors, but the practical significance of activity level was minimal. The ICCs were [inter](intra): KL [0.79] (0.84), patient management [0.54].

CONCLUSION

When evaluating glenohumeral osteoarthritis, patient symptoms and KL grade are the factors most strongly associated with treatment. In operative cases, the factors most strongly associated with the choice of operation were the patient's KL grade and age. Additionally, the KL classification demonstrated excellent observer reliability. However, there was only moderate agreement among shoulder specialists regarding treatment, indicating that this remains a controversial topic.

Abstract PD3-07: A phase II pre-surgical trial of lapatinib for the treatment of women with HER2 positive or EGFR positive ductal carcinoma in situ

Background: Estrogen receptor (ER)-negative tumors and human epidermal growth factor 2-Neu (HER2) positive breast cancers are known to be more clinically aggressive subtypes of breast cancer and account for 30% of all breast cancers. Women with HER2 + breast cancers, whether ER+ or ER -, require cytotoxic chemotherapy with a HER2-targeting agent, and often have adverse outcomes. Thus, preventive agents are needed to reduce the incidence of these subtypes of aggressive breast cancer. Lapatinib, a dual tyrosine kinase inhibitor, inhibits epidermal growth factor receptors (EGFR) and HER2 kinases and has shown to decrease breast cell proliferation in invasive breast cancer and adjacent premalignant lesions. Therefore, we conducted a multi-institutional randomized Phase II clinical trial to study the effects of the signal transduction inhibitor lapatinib in women with HER2-positive or EGFR-positive ductal carcinoma in situ (DCIS).

Methods: Randomized participants received either lapatinib (750mg, 1000mg, or 1500mg) or placebo daily for 2-6 weeks prior to their surgery. After minimal accrual, the trial was later amended to lapatinib 1000mg or placebo. Pre-treatment breast tissue was obtained from initial diagnostic core biopsy and post-treatment breast tissue was obtained from surgical excision specimen. Blood was obtained prior to surgery to assess serum lapatinib level. Participants kept a daily symptom assessment log and had a cardiac assessment at baseline and prior to surgery. Patients were instructed to take drug up to and including the day before surgery. The dual primary endpoint for this study was change in proliferation in pre- versus post-treatment biopsies between the two treatment arms, as measured by Ki67 as well as toxicity assessment. Secondary endpoints included incidence of DCIS at surgery and modulation of tissue biomarker expression in growth factor receptors (EGFR, ErbB2); phosphorylated growth factor receptor (phospho-ErbB2); signal transduction markers (MAPK, phospho-MAPK); hormone receptors (ER, PR); and p27.

Results:Twenty-two women (mean age: 51; range: 32-66) with HER2+ or EGFR+ DCIS were treated with lapatinib (1,000 or 1,500 mg) or placebo for 2–6 weeks prior to surgical excision. Ki67 expression was significantly decreased in the lapatinib treatment arms compared to placebo (p=0.0122). Diarrhea, fatigue, and skin reactions were notable adverse events that occurred predominately in the lapatinib arm compared to placebo. No grade 3 or 4 events related to the study drug were noted during the study. No changes were noted in cardiac function. DCIS was present in all surgical specimens in both arms. Invasive breast cancer was noted in 1 patient on lapatinib 1000mg and 3 patients on placebo. No statistically significant changes were noted in signal transduction biomarkers

Conclusion:These results demonstrate the effectiveness of lapatinib in reducing proliferation in women with EGFR+ or HER2+ DCIS. Even low-grade toxicities can deter use of an agent in the prevention setting. This and the lack of a risk model for HER2+ and triple negative breast cancer make the development of larger scale clinical prevention trials of lapatinib for the prevention a challenge.

Citation Format: Thomas PS, Contreras A, Pruthi S, Krontiras H, Rimawi M, Garber J, Wang T, Hilsenbeck SG, Vornik LA, Gilmer T, Friedman R, Heckman-Stoddard BM, Dunn B, Kuerer H, Brown PH. A phase II pre-surgical trial of lapatinib for the treatment of women with HER2 positive or EGFR positive ductal carcinoma in situ [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD3-07.

Abstract 48: Role of Receptor for Advanced Glycation End Products (RAGE) in Regression of Diabetic Atherosclerosis

Atherosclerosis is a chronic inflammatory disorder. Both progression and regression of atherosclerosis are adversely affected by diabetes. A key player in these processes is Receptor for Advanced Glycation End Products (RAGE). RAGE is a multiligand cell surface macromolecule, which binds ligands enriched in atherosclerotic plaques, such as advanced glycation endproducts (AGEs). RAGE is expressed on a wide array of cell types implicated in cardiovascular disease, such as endothelial cells, and inflammatory cells such as macrophages. The cytoplasmic domain of RAGE binds to the formin molecule DIAPH1 and DIAPH1 is required for RAGE ligands to activate cell signaling responses. RAGE acts as a key mediator of oxidative and inflammatory signaling pathways that are involved in atherosclerosis. We tested mechanisms of impaired regression of atherosclerosis in a murine model of aorta transplantation and found that deletion of Ager or Diaph1 in diabetic mice recipients of Ldlr null mice atherosclerotic aortas accelerates atherosclerosis regression and significantly reduces the lesional macrophage content when compared to diabetic wild-type recipient mice. The antiatherosclerotic effects in diabetic Ager null mice and diabetic Diaph1 null mice include reduced RAGE ligand AGEs in transplanted aortas, with reduced expression of a range of proatherogenic factors, including reactive oxygen species and inflammatory cytokines implicated in leukocyte recruitment and activation. We employed RNA sequencing to identify the key transcriptional events by which RAGE mediates its effects in donor or recipient macrophages in diabetic regressing plaques. Our results suggest that critical gene expression profiles, including those genes involved in inflammation, endothelial dysfunction, oxidative stress, monocyte/macrophage fate (recruitment, differentiation, proliferation), signal transduction and lipid metabolism, are beneficially modulated, at least in part, via Ager deletion in atherosclerosis regression. Taken together, these data increase our understanding of the role of RAGE in diabetic atherosclerosis, particularly in macrophages, and may provide avenues for therapeutic strategies to accelerate regression of atherosclerosis in diabetes.

Opposite roles of cannabinoid receptors 1 and 2 in hepatocarcinogenesis

OBJECTIVE

The endocannabinoid system (ECS) exerts key roles in the development of liver fibrosis and fatty liver, two diseases that promote the development of hepatocellular carcinoma (HCC). Although cannabinoids exert potent antitumour effects in vitro, the contribution of the ECS to carcinogenesis in vivo remains elusive.

DESIGN

Expression of key components of the ECS, including endocannanabinoids, endocannabinoid-degrading enzymes and endocannabinoid receptors, was determined in healthy liver and tumours. Diethylnitrosamine-induced hepatocarcinogenesis was determined in mice deficient in fatty acid amide hydrolase (FAAH), the main anandamide (AEA)-degrading enzyme, in cannabinoid receptor (CB)1, CB2, or transient receptor potential cation channel subfamily V member 1 (TRPV1)-deficient mice.

RESULTS

Murine and human HCCs displayed activation of the ECS with strongly elevated expression of CB1 and CB2 but only moderately altered endocannabinoid levels. Contrary to the antitumour effects of cannabinoids in vitro, we observed increased hepatocarcinogenesis in FAAH-deficient mice, a mouse model with increased AEA levels. Accordingly, inactivation of CB1, the main receptor for AEA, in wild-type or FAAH-deficient mice suppressed hepatocarcinogenesis. In contrast, inactivation of CB2 increased hepatocarcinogenesis. CB1 was strongly expressed within HCC lesions and its inactivation suppressed proliferation and liver fibrosis. CB2 was predominantly expressed in macrophages. CB2 inactivation decreased the expression of T-cell-recruiting chemokines and inhibited hepatic T-cell recruitment including particular CD4+ T cells, a population with known antitumour effects in HCC. TRPV1 deletion did not alter HCC development.

CONCLUSIONS

Similar to their role in fibrogenesis, CB1 and CB2 exert opposite effects on hepatocarcinogenesis and may provide novel therapeutic targets.

Clinical and Radiographic Outcomes of the Simpliciti Canal-Sparing Shoulder Arthroplasty System: A Prospective Two-Year Multicenter Study

BACKGROUND

Stemmed humeral components have been used since the 1950s; canal-sparing (also known as stemless) humeral components became commercially available in Europe in 2004. The Simpliciti total shoulder system (Wright Medical, formerly Tornier) is a press-fit, porous-coated, canal-sparing humeral implant that relies on metaphyseal fixation only. This prospective, single-arm, multicenter study was performed to evaluate the two-year clinical and radiographic results of the Simpliciti prosthesis in the U.S.

METHODS

One hundred and fifty-seven patients with glenohumeral arthritis were enrolled at fourteen U.S. sites between July 2011 and November 2012 in a U.S. Food and Drug Administration (FDA) Investigational Device Exemption (IDE)-approved protocol. Their range of motion, strength, pain level, Constant score, Simple Shoulder Test (SST) score, and American Shoulder and Elbow Surgeons (ASES) score were compared between the preoperative and two-year postoperative evaluations. Statistical analyses were performed with the Student t test with 95% confidence intervals. Radiographic evaluation was performed at two weeks and one and two years postoperatively.

RESULTS

One hundred and forty-nine of the 157 patients were followed for a minimum of two years. The mean age and sex-adjusted Constant, SST, and ASES scores improved from 56% preoperatively to 104% at two years (p < 0.0001), from 4 points preoperatively to 11 points at two years (p < 0.0001), and from 38 points preoperatively to 92 points at two years (p < 0.0001), respectively. The mean forward elevation improved from 103° ± 27° to 147° ± 24° (p < 0.0001) and the mean external rotation, from 31° ± 20° to 56° ± 15° (p < 0.0001). The mean strength in elevation, as recorded with a dynamometer, improved from 12.5 to 15.7 lb (5.7 to 7.1 kg) (p < 0.0001), and the mean pain level, as measured with a visual analog scale, decreased from 5.9 to 0.5 (p < 0.0001). There were three postoperative complications that resulted in revision surgery: infection, glenoid component loosening, and failure of a subscapularis repair. There was no evidence of migration, subsidence, osteolysis, or loosening of the humeral components or surviving glenoid components.

CONCLUSIONS

The study demonstrated good results at a minimum of two years following use of the Simpliciti canal-sparing humeral component. Clinical results including the range of motion and the Constant, SST, and ASES scores improved significantly, and radiographic analysis showed no signs of loosening, osteolysis, or subsidence of the humeral components or surviving glenoid components.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Epithelial Transforming Growth Factor-β Signaling Does Not Contribute to Liver Fibrosis but Protects Mice From Cholangiocarcinoma

BACKGROUND & AIMS

Transforming growth factor-β (TGFβ) exerts key functions in fibrogenic cells, promoting fibrosis development in the liver and other organs. In contrast, the functions of TGFβ in liver epithelial cells are not well understood, despite their high level of responsiveness to TGFβ. We sought to determine the contribution of epithelial TGFβ signaling to hepatic fibrogenesis and carcinogenesis.

METHODS

TGFβ signaling in liver epithelial cells was inhibited by albumin-Cre-, K19-CreERT-, Prom1-CreERT2-, or AAV8-TBG-Cre-mediated deletion of the floxed TGFβ receptor II gene (Tgfbr2). Liver fibrosis was induced by carbon tetrachloride, bile duct ligation, or disruption of the multidrug-resistance transporter 2 gene (Mdr2). Hepatocarcinogenesis was induced by diethylnitrosamine or hepatic deletion of PTEN.

RESULTS

Deletion of Tgfbr2 from liver epithelial cells did not alter liver injury, toxin-induced or biliary fibrosis, or diethylnitrosamine-induced hepatocarcinogenesis. In contrast, epithelial deletion of Tgfbr2 promoted tumorigenesis and reduced survival of mice with concomitant hepatic deletion of Pten, accompanied by an increase in tumor number and a shift from hepatocellular carcinoma to cholangiocarcinoma. Surprisingly, both hepatocyte- and cholangiocyte-specific deletion of Pten and Tgfbr2 promoted the development of cholangiocarcinoma, but with different latencies. The prolonged latency and the presence of hepatocyte-derived cholangiocytes after AAV8-TBG-Cre-mediated deletion of Tgfbr2 and Pten indicated that cholangiocarcinoma might arise from hepatocyte-derived cholangiocytes in this model. Pten deletion resulted in up-regulation of Tgfbr2, and deletion of Tgfbr2 increased cholangiocyte but not hepatocyte proliferation, indicating that the main function of epithelial TGFBR2 is to restrict cholangiocyte proliferation.

CONCLUSIONS

Epithelial TGFβ signaling does not contribute to the development of liver fibrosis or formation of hepatocellular carcinomas in mice, but restricts cholangiocyte proliferation to prevent cholangiocarcinoma development, regardless of its cellular origin.

Rate of Improvement in Clinical Outcomes with Anatomic and Reverse Total Shoulder Arthroplasty

INTRODUCTION

The rate of clinical improvement has never been studied after anatomic (aTSA) and reverse (rTSA) total shoulder arthroplasty. This study quantifies the rate of improvement after aTSA and rTSA using five different scoring metrics for 1,641 patients.

METHODS

We evaluated 1,641 (69 ± 9.3 years old) patients treated by 14 orthopaedic surgeons using either aTSA or rTSA with a single platform shoulder system. Seven hundred twenty-nine patients received aTSA, and 912 patients received rTSA. Each patient was scored preoperatively and at various follow-up intervals (2 weeks, 6 weeks, 3 months, 6 months, annually, etc.) with a maximum follow-up time of 139 months using the SST, UCLA, ASES, Constant, and SPADI metrics. In addition, range of motion was measured. The rate of improvement was analyzed using a 40-point moving filter treadline over the entire range of follow-up.

RESULTS

All metrics improved in a majority of patients with less than 5% worsening after 6 months. While gains in motion were present in the majority of patients after aTSA, a higher incidence of patients failed to experience improvement in range of motion after rTSA. Clinical worsening was seen in up to 10% and 20% of the visits for active flexion and abduction and external rotation, respectively. The majority of clinical improvement after aTSA and rTSA was noted in the first 6 months with full improvement noted by 12 to 24 months. During the first 12 months, the rate of improvement associated with rTSA patients was generally 30% larger than that of aTSA patients.

DISCUSSION

The results of this large-scale database analysis demonstrate the reliability of improvements in outcomes and motion achieved with both aTSA and rTSA for various indications. For both aTSA and rTSA, less than 5% of patients reported worsening in each of the five clinical metrics after 6 months postoperative follow-up time. This study is significant because it quantifies how patient outcomes improve with time following treatment with both aTSA and rTSA. These results can be used to establish realistic patient expectations regarding the typical follow-up time required for pain to be reduced and function restored following surgical treatment with a total shoulder prosthesis.

Preliminary Results of a Novel Hybrid Cage Glenoid Compared to an All-Polyethylene Glenoid in Total Shoulder Arthroplasty

INTRODUCTION

The aim of this study was to evaluate the preliminary outcomes of a hybrid cage glenoid design in comparison to pegged all-polyethylene glenoid components in anatomic total shoulder arthroplasty (aTSA).

MATERIALS AND METHODS

Ninety-two patients undergoing primary anatomic total shoulder arthroplasty with minimum two-year follow-up were reviewed. Forty-six patients had an ultra-high molecular weight polyethylene (UHMWPE) cemented pegged glenoid component, and 46 had a hybrid cage glenoid component. Patient data was retrospectively reviewed from prospectively acquired data in a multi-institutional IRB approved database. These age, gender, and follow-up matched patients were evaluated and scored preoperatively and a latest follow-up using the SST, UCLA, ASES, Constant, and SPADI scoring metrics. Additional measures included active abduction, elevation, and external rotation. Radiolucent line assessment of the glenoid was performed by use of a Grashey and axillary radiograph at latest follow-up. A Student's two tailed, unpaired t-test was used to identify differences in preoperative and postoperative results, where p < 0.05 denoted a significant difference.

RESULTS

All patients demonstrated significant improvements in pain and function following treatment with the primary aTSA. The database contained three complications for the aTSA patients with a cage glenoid, and three complications for patients with a UHMWPE pegged glenoid. Radiographic data was available for 37 of 46 cage glenoid patients and 29 of 46 UHMWPE pegged glenoid patients. Five of 37 cage glenoid patients had a radiolucent line (13.5%) with an average radiographic line score of 0.22. Eight of 29 UHMWPE peg glenoid patients had a radiolucent line (27.6%) with an average radiographic line score of 0.57. Cage aTSA patients were associated with significantly less blood loss than aTSA UHMWPE pegged glenoid patients (avg. blood loss = 242 vs. 337; p = 0.022).

CONCLUSION

At minimum two-year follow-up, hybrid cage aTSA components show equal clinical outcomes to UHMWPE pegged glenoids. However, the hybrid cage components had significantly fewer radiolucent lines and less intra-operative blood loss. Additional and longer-term clinical and radiographic follow-up is necessary to confirm these promising early results.

The Impact of Posterior Wear on Reverse Shoulder Glenoid Fixation

INTRODUCTION

Achieving glenoid fixation with posterior bone loss can be challenging. The purpose of this study was to quantify the impact of two different sizes of posterior glenoid defects (10° and 20°) on reverse shoulder arthroplasty (rTSA) glenoid baseplate fixation and determine if utilizing different sizes of posterior augmented baseplates (8° and 16°) with off-axis reaming provides comparable fixation to using a standard baseplate with different amounts of eccentric reaming.

METHODS

We quantified the impact of 10° and 20° posterior glenoid defects on rTSA baseplate fixation in composite scapulae using the ASTM F2028-14 rTSA glenoid loosening test method. Forty-two total implants (N = 7 for each size defect and for each type of baseplate) were tested at 750 N for 10,000 cycles. Baseplate displacement was measured before and after cyclic loading in the superior-inferior and anterior-posterior directions. Statistical analysis was performed with a two-tailed unpaired Student's t-test (significance defined as p < 0.05) to compare prosthesis displacements relative to each scapula (10° and 20° posterior defects for each type of baseplate versus the non-defect control) before and after cyclic loading.

RESULTS

All glenoid baseplates remained well-fixed after cyclic loading in composite scapulae without a defect and in scapulae with posterior defects. Increased pre- and post-cyclic displacement was observed with increased posterior defect size and differences in displacement were observed between standard and augmented baseplates. Augmented baseplates were observed to remove significantly less bone than standard baseplates when correcting posterior defects, regardless of size.

DISCUSSION

Both standard baseplates with eccentric reaming and two different sizes of augmented baseplates with off-axis reaming successfully maintained fixation following cyclic loading in composite scapula with corrected 10° and 20° posterior glenoid defects. Augmented glenoids may be more advantageous long-term from a fixation perspective as they preserve more subchondral glenoid bone due to the minimal reaming occurring by the off-axis method. Mid and long-term clinical follow-up comparisons of outcomes are necessary between these two techniques.

Abstract 532: The Receptor for Advanced Glycation End Products (RAGE) Suppresses Macrophage Cholesterol Transport in Diabetes

Diabetes is a leading cause of cardiovascular morbidity and mortality. In human subjects, diabetes suppresses macrophage cholesterol efflux capacity, at least in part via reduction in levels of the major cholesterol transporters, ABCA1 and ABCG1. We tested the hypothesis that the receptor for advanced glycation end products (RAGE) contributes to these processes. We report that ligand-RAGE interaction suppresses cholesterol efflux to ApoA1 and HDL in primary murine bone marrow-derived macrophages (BMDMs) and in human THP-1 cells, at least in part via downregulation of ABCA1 and ABCG1. In vivo, compared to cholesterol-loaded wild-type (WT) diabetic murine BMDMs, diabetic BMDMs devoid of Ager (gene encoding RAGE) displayed significantly higher reverse cholesterol transport (RCT) to plasma, liver and feces when injected into WT non-diabetic mice. In atherosclerotic plaques from mice devoid of both Ldlr and Ager and fed a high cholesterol diet, higher Abca1 and Abcg1 mRNA transcript levels were also observed compared to Ager-expressing LDL receptor null mice. RAGE ligand AGEs suppress ABCG1 promoter luciferase activity and transcription of ABCG1 through reduced binding of PPARgamma (PPARG) to PPARG-responsive elements in the ABCG1 promoter. These data reveal that RAGE contributes to dysregulation of macrophage cholesterol metabolism, particularly in diabetes. We infer that antagonism of RAGE may mitigate accelerated atherosclerosis in the diabetic state, at least in part due to modulation of impaired cholesterol transport.

Isolation and characterisation of the fungus Spiromastix asexualis sp. nov. from discospondylitis in a German Shepherd dog, and review of Spiromastix with the proposal of the new order Spiromastixales (Ascomycota)

The genus Spiromastix consists of several fungal species that have been isolated from soil and animal dung in various parts of the world. However, these species are considered to be of low pathogenic potential, as no cases of infections caused by these fungi have been reported. Here, we describe the clinical course of discospondylitis in a dog from which a fungus was cultured from a biopsy and identified as a Spiromastix species by morphologic characteristics and sequencing. Phylogenetic analysis determined this to be a new species, Spiromastix asexualis, which is described, and a new order, Spiromastixales, is proposed.

High-mobility group box 1 is dispensable for autophagy, mitochondrial quality control, and organ function in vivo

In vitro studies have demonstrated a critical role for high-mobility group box 1 (HMGB1) in autophagy and the autophagic clearance of dysfunctional mitochondria, resulting in severe mitochondrial fragmentation and profound disturbances of mitochondrial respiration in HMGB1-deficient cells. Here, we investigated the effects of HMGB1 deficiency on autophagy and mitochondrial function in vivo, using conditional Hmgb1 ablation in the liver and heart. Unexpectedly, deletion of Hmgb1 in hepatocytes or cardiomyocytes, two cell types with abundant mitochondria, did not alter mitochondrial structure or function, organ function, or long-term survival. Moreover, hepatic autophagy and mitophagy occurred normally in the absence of Hmgb1, and absence of Hmgb1 did not significantly affect baseline and glucocorticoid-induced hepatic gene expression. Collectively, our findings suggest that HMGB1 is dispensable for autophagy, mitochondrial quality control, the regulation of gene expression, and organ function in the adult organism.

Allogeneic blood transfusions and postoperative infections after total hip or knee arthroplasty

BACKGROUND

Up to 70% of patients who undergo total hip or total knee arthroplasty receive blood transfusions. Using data from more than 12,000 patients assessed in the Phase-III RECORD (Regulation of Coagulation in Orthopedic Surgery to Prevent Deep Venous Thrombosis and Pulmonary Embolism) studies, we investigated whether allogeneic blood transfusion increases the risk of postoperative infection compared with autologous blood transfusion or no transfusion.

METHODS

A post hoc analysis of the pooled RECORD data stratified patients into three groups according to the type of blood transfusion that they received: no transfusion (n = 6313), autologous blood transfusion (n = 1902), and allogeneic blood transfusion with or without autologous blood transfusion (n = 3962). The types of postoperative infection were recorded and included lower or upper respiratory tract and lung infection, bone and joint infection, wound inflammation or infection, urinary tract infection, and other infections.

RESULTS

The rates of infection in patients receiving no transfusion or autologous blood transfusion were similar; therefore, data from these two groups were combined. The rate of any infection was 9.9% (392 of 3962) in patients receiving allogeneic blood transfusion and 7.9% (646 of 8215) in patients not receiving allogeneic blood transfusion with or without autologous blood transfusion (p = 0.003). The rates of lower or upper respiratory tract and lung infection (2.1% [eighty-five of 3962] versus 1.3% [109 of 8215]; p = 0.002) and of wound inflammation or infection (2.4% [ninety-four of 3962] versus 1.7% [138 of 8215]; p = 0.046) were significantly higher in patients receiving allogeneic blood transfusion compared with patients not receiving allogeneic blood transfusion. When comparing patients who had received allogeneic blood transfusion with those who had not received allogeneic blood transfusion, the rates of bone and joint infection (0.4% [fourteen of 3962] versus 0.2% [eighteen of 8215]; p = 0.056), of urinary tract infection (3.1% [123 of 3962] versus 2.5% [209 of 8215]; p = 0.551), and of other infections (3.0% [120 of 3962] versus 2.7% [225 of 8215]; p = 0.308) were not significantly different.

CONCLUSIONS

The rates of any infection, lower or upper respiratory tract and lung infection, and wound inflammation or infection were significantly increased after elective total hip or total knee arthroplasty in patients receiving allogeneic blood transfusion compared with those receiving autologous blood transfusion or no blood transfusion.

Hepatic macrophages but not dendritic cells contribute to liver fibrosis by promoting the survival of activated hepatic stellate cells in mice

Although it is well established that hepatic macrophages play a crucial role in the development of liver fibrosis, the underlying mechanisms remain largely elusive. Moreover, it is not known whether other mononuclear phagocytes such as dendritic cells (DCs) contribute to hepatic stellate cell (HSC) activation and liver fibrosis. We show for the first time that hepatic macrophages enhance myofibroblast survival in a nuclear factor kappa B (NF-κB)-dependent manner and thereby promote liver fibrosis. Microarray and pathway analysis revealed no induction of HSC activation pathways by hepatic macrophages but a profound activation of the NF-κB pathway in HSCs. Conversely, depletion of mononuclear phagocytes during fibrogenesis in vivo resulted in suppressed NF-κB activation in HSCs. Macrophage-induced activation of NF-κB in HSCs in vitro and in vivo was mediated by interleukin (IL)-1 and tumor necrosis factor (TNF). Notably, IL-1 and TNF did not promote HSC activation but promoted survival of activated HSCs in vitro and in vivo and thereby increased liver fibrosis, as demonstrated by neutralization in coculture experiments and genetic ablation of IL-1 and TNF receptor in vivo. Coculture and in vivo ablation experiments revealed only a minor contribution to NF-κB activation in HSCs by DCs, and no contribution of DCs to liver fibrosis development, respectively.

CONCLUSION

Promotion of NF-κB-dependent myofibroblast survival by macrophages but not DCs provides a novel link between inflammation and fibrosis.

Abstract 3900: Alpha2beta1 integrin regulation of endothelial notch signaling in the retina

Angiogenesis expands the vascular network during normal development and in response to angiogenic stress. Dysregulation of this dynamic process contributes to tumor progression and to the pathogenesis of many diseases. Evidence suggests that the alpha2beta1 integrin, a collagen and laminin receptor, plays an important role in angiogenesis. In the wound-healing and tumor microenvironment, deletion of the alpha2beta1 integrin has been reported to increase neoangiogenesis. In contrast, small molecule inhibitor (SMI) targeting of the alpha2 integrin blocks sprouting angiogenesis.

To reconcile these divergent findings and gain a fuller understanding of alpha2beta1 integrin's role in angiogenesis we turned to the retina. The retinal model is uniquely suited for angiogenesis investigations as the retinal vasculature develops postnatally in a 2-dimensional plane in a well-characterized manner. Evaluation of the alpha2-null retina reveals a constellation of defects and delays in vascular development, including delayed vessel outgrowth, and increased vessel irregularity and decreased plexus density at the vascular front.

Additionally we determined that alpha2 integrin-deletion has a protective effect in an oxygen-induced retinopathy model of retinopathy of prematurity (ROP) in mice by inhibiting both hyperoxia-induced vaso-obliteration and hypoxia-induced pathologic neovascularization. Confirming this result, our analysis of human microarray data shows, for the first time, that preterm infants with lower ITGA2 expression are less likely to suffer from ROP. This work clarifies the role of alpha2beta1 integrin in sprouting angiogenesis and raises the intriguing possibility of alpha2 integrin targeted therapies for prevention of ROP.

These changes are reminiscent of changes observed in other models with dysregulated notch signaling. Recent studies reported that the alpha2beta1 integrin regulates sprouting angiogenesis by inducing DLL4 in ‘tip cells’. We show, for the first time, notch induced downregulation of alpha2beta1 integrin expression in ‘stalk cells’. Together these results suggest that the alpha2beta1 integrin coordinates endothelial notch signaling by stabilizing tip-stalk status. The apparent discrepancy between the effects of the alpha2 integrin inhibition and integrin-deletion may reflect differences between acute and chronic upregulation of notch signaling. We propose that synergistic use of notch and alpha2 integrin targeted therapies may provide enhanced anti-tumor angiogenesis.

Citation Format: Aasakiran Madamanchi, Megan Capozzi, Ling Geng, Zhengzhi Li, Zhonghua Zhang, Richard Friedman, Kent Dickeson, John Penn, Mary Zutter. Alpha2beta1 integrin regulation of endothelial notch signaling in the retina. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3900. doi:10.1158/1538-7445.AM2013-3900

Transcriptional switching model for the regulation of tumorigenesis and metastasis by the ha-ras oncogene - transcriptional changes in the ha-ras tumor-suppressor gene lysyl oxidase

A model system is described that allows an analysis of the molecular and biochemical changes associated with expression and suppression of the oncogenic and metastatic phenotype of cloned rat embryo fibroblast (CREF) cells. Ha-ras-transformed CREF cells are morphologically transformed, anchorage-independent and both tumorigenic and metastatic in athymic nude mice and syngeneic Fischer rats. Co-expression of the Ha-ras oncogene and Krev-1 tumor suppressor gene in CREF cells results in suppression of in vitro transformation. In contrast, Ha-ras/Krev-1 transformed CREF cells retain, with greatly extended latency periods, both tumorigenic and metastatic capabilities in athymic nude mice. The present study investigates changes in the Ha-ms suppressor gene, rrg (lysyl oxidase), during expression and suppression of the oncogenic phenotype in CREF cells. Nontumorigenic CREF cells and CREF cells transformed by the Ha-ras and Krev-1 gene that express a suppression in in vitro transformation contain elevated levels of lysyl oxidase mRNA and protein. In contrast, Ha-ms and Ha-ras/Krev-1 nude mouse tumor- and nude mouse lung metastasis-derived CREF cells contain reduced levels of lysyl oxidase mRNA and protein. Nuclear run-on assays indicate that suppression of lysyl oxidase expression in transformed subclones of CREF cells correlates with a reduction in transcription of the lysyl oxidase gene. Taken together, the current studies support a transcriptional switching model in which lysyl oxidase expression correlates directly with suppression of the Ka-ms-induced transformation phenotype and escape from oncogenic suppression correlates with a transcriptional silencing of the lysyl oxidase gene and decreased lysyl oxidase mRNA and protein.

Promotion of hepatocellular carcinoma by the intestinal microbiota and TLR4

Increased translocation of intestinal bacteria is a hallmark of chronic liver disease and contributes to hepatic inflammation and fibrosis. Here we tested the hypothesis that the intestinal microbiota and Toll-like receptors (TLRs) promote hepatocellular carcinoma (HCC), a long-term consequence of chronic liver injury, inflammation, and fibrosis. Hepatocarcinogenesis in chronically injured livers depended on the intestinal microbiota and TLR4 activation in non-bone-marrow-derived resident liver cells. TLR4 and the intestinal microbiota were not required for HCC initiation but for HCC promotion, mediating increased proliferation, expression of the hepatomitogen epiregulin, and prevention of apoptosis. Gut sterilization restricted to late stages of hepatocarcinogenesis reduced HCC, suggesting that the intestinal microbiota and TLR4 represent therapeutic targets for HCC prevention in advanced liver disease.

Evidence for direct impact damage in metamict titanite CaTiSiO₅

We have measured the dose dependence of the degree of amorphization of titanite, CaTiSiO(5). Titanite is an often metamict mineral which has been considered as a matrix for the encapsulation of radiogenic waste, such as Pu. The amorphous fraction p of geologically irradiated samples (ages between 0.3 and 1 Ga) follows p = 1 - exp(-B(a)D) where D is the total dose and the characteristic amorphization mass is B(a) = 2.7(3) × 10(-19) g. Amorphization follows the direct impact mechanism where each α-decay leads to a recoil of the radiogenic atoms (mostly Th and U), which then, in turn, displaces some 5000 atoms of the titanite matrix. The amorphization behaviour is almost identical with that of zircon, ZrSiO(4), which has a similar molecular mass. While the recrystallization mechanism and elastic behaviour of the two minerals are very different, we do not find significant differences for the amorphization mechanism. Our samples have undergone little reheating over their geological history, since heating over 800 K would lead to rapid recrystallization for which we have found no evidence.

Bile acid and inflammation activate gastric cardia stem cells in a mouse model of Barrett-like metaplasia

Esophageal adenocarcinoma (EAC) arises from Barrett esophagus (BE), intestinal-like columnar metaplasia linked to reflux esophagitis. In a transgenic mouse model of BE, esophageal overexpression of interleukin-1β phenocopies human pathology with evolution of esophagitis, Barrett-like metaplasia and EAC. Histopathology and gene signatures closely resembled human BE, with upregulation of TFF2, Bmp4, Cdx2, Notch1, and IL-6. The development of BE and EAC was accelerated by exposure to bile acids and/or nitrosamines, and inhibited by IL-6 deficiency. Lgr5(+) gastric cardia stem cells present in BE were able to lineage trace the early BE lesion. Our data suggest that BE and EAC arise from gastric progenitors due to a tumor-promoting IL-1β-IL-6 signaling cascade and Dll1-dependent Notch signaling.

Acute Cardiac Resynchronization Therapy for the Failing Left, Right, or Single Ventricle After Repaired Congenital Heart Disease

Use of cardiac resynchronization in children and young adults with congenital heart disease has been described in a variety of anecdotal cases and pooled institutional summaries which report mid-term results. This manuscript addresses use of cardiac resynchronization and/or multisite pacing in children in the acute postoperative period with a failing right, left, or single ventricle.

Bone marrow-derived myofibroblasts contribute to the mesenchymal stem cell niche and promote tumor growth

Carcinoma-associated fibroblasts (CAFs) that express α-smooth muscle actin (αSMA) contribute to cancer progression, but their precise origin and role are unclear. Using mouse models of inflammation-induced gastric cancer, we show that at least 20% of CAFs originate from bone marrow (BM) and derive from mesenchymal stem cells (MSCs). αSMA+ myofibroblasts (MFs) are niche cells normally present in BM and increase markedly during cancer progression. MSC-derived CAFs that are recruited to the dysplastic stomach express IL-6, Wnt5α and BMP4, show DNA hypomethylation, and promote tumor growth. Moreover, CAFs are generated from MSCs and are recruited to the tumor in a TGF-β- and SDF-1α-dependent manner. Therefore, carcinogenesis involves expansion and relocation of BM-niche cells to the tumor to create a niche to sustain cancer progression.

Deletion of the receptor for advanced glycation end products reduces glomerulosclerosis and preserves renal function in the diabetic OVE26 mouse

OBJECTIVE

Previous studies showed that genetic deletion or pharmacological blockade of the receptor for advanced glycation end products (RAGE) prevents the early structural changes in the glomerulus associated with diabetic nephropathy. To overcome limitations of mouse models that lack the progressive glomerulosclerosis observed in humans, we studied the contribution of RAGE to diabetic nephropathy in the OVE26 type 1 mouse, a model of progressive glomerulosclerosis and decline of renal function.

RESEARCH DESIGN AND METHODS

We bred OVE26 mice with homozygous RAGE knockout (RKO) mice and examined structural changes associated with diabetic nephropathy and used inulin clearance studies and albumin:creatinine measurements to assess renal function. Transcriptional changes in the Tgf-beta1 and plasminogen activator inhibitor 1 gene products were measured to investigate mechanisms underlying accumulation of mesangial matrix in OVE26 mice.

RESULTS

Deletion of RAGE in OVE26 mice reduced nephromegaly, mesangial sclerosis, cast formation, glomerular basement membrane thickening, podocyte effacement, and albuminuria. The significant 29% reduction in glomerular filtration rate observed in OVE26 mice was completely prevented by deletion of RAGE. Increased transcription of the genes for plasminogen activator inhibitor 1, Tgf-beta1, Tgf-beta-induced, and alpha1-(IV) collagen observed in OVE26 renal cortex was significantly reduced in OVE26 RKO kidney cortex. ROCK1 activity was significantly lower in OVE26 RKO compared with OVE26 kidney cortex.

CONCLUSIONS

These data provide compelling evidence for critical roles for RAGE in the pathogenesis of diabetic nephropathy and suggest that strategies targeting RAGE in long-term diabetes may prevent loss of renal function.

A Phase I Trial of a Pegylated Liposomal Anthracycline (Doxil TM) and Lapatinib Combination in the Treatment of Metastatic Breast Cancer: Dose-Escalation Results of an Anthracycline and Lapatinib Combination Trial

Background: Liposomal formulations such as pegylated liposomal doxorubicin (PLD) were developed to improve the therapeutic index and overall benefit of the anthracyclines (A). Lapatinib (L) is a selective and highly competitive inhibitor of ErbB1 and ErbB2 tyrosine kinases. The combination of conventional doxorubicin and an ErbB2 targeting agent (trastuzumab) was effective but led to an unacceptable risk of cardiac toxicity. The combination of PLD and L however may be effective with less cardiac risk. Methods: This is an open-label, phase I, dose-escalation trial of PLD at 20, 30, 45 and 60 mg/m2 IV every 4 weeks (maximum of 8 doses) and L, 1500 mg po daily until progression in patients (pts) with metastatic breast cancer (MBC). EGFR and/or ErbB2 positivity was not required. Prior chemotherapy, endocrine therapy and trastuzumab were allowed however prior A use was limited to 240 mg/m2 of doxorubicin or 600 mg/m2 of epirubicin. Initially, prior EGFR targeting therapies were not allowed however the trial was subsequently amended to allow prior lapatinib. Concomitant CYP3A4 inducers/ inhibitors were not allowed. A left ventricular ejection fraction (LVEF) of ≥ 50% was required. The primary objective was to evaluate the safety, tolerability and feasibility of the combination of PLD and L, particularly with respect to cardiac safety. MUGAs were performed at entry and every 8 weeks thereafter. Results: 16 patients (PLD: 20 mg/m2 - 4 pts; 30 mg/m2 - 3 pts; 45 mg/m2 – 6 pts; 60 mg/m2- 3 pts) with a mean age of 53 yrs (range, 33-68) have been treated for a total of 30 treatment cycles. Dose-limiting toxicity (DLT) was not reached. One pt experienced an LVEF drop to &lt; 50% after 4 cycles however this was accompanied by a pericardial effusion felt to be secondary to progressive disease. Adverse events observed include: grade IV- mucus plugging and knee pain in 1 pt each; grade III- fatigue and hand-foot-syndrome (HFS) in 2 pts each and edema, diarrhea, dizziness, headache, stomatitis and skin toxicity in 1 pt each; grade I/II in ≥2 pts- anemia, leucopenia, fatigue, shortness of breath, pain, nausea, stomatitis, anorexia, diarrhea, increased alkaline phosphatase or transaminases, hypoalbuminemia and hyperglycemia. Preliminary response data in 11 evaluable pts reveals 1 PR, 3 SD, and 8 PD. Event-free and overall survival curves are as shown.Conclusions: In the first 16 pts treated, the combination of PLD and L has been well tolerated without treatment-related cardiac toxicity. One pt experienced an LVEF drop to &lt; 50%, however this was felt likely to be disease-related. DLT was not reached however grade 3 HFS occurred in 2 out of 3 pts in the 60 mg/m2 cohort. A pharmacokinetic interaction cohort at the 45 mg/m2 dose is planned.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3096.

Degree of catecholamine hypersecretion is the most important determinant of intra-operative hemodynamic outcomes in pheochromocytoma

Pheochromocytoma resection is often complicated by intra-operative hypertension and post-resection hypotension. Factors associated with these hemodynamic alterations are not well defined. The aim of this study was to analyse the clinical-laboratory features associated with hemodynamic parameters during pheochromocytoma resection. Twenty-seven patients submitted to tumor resection - either open (no.=18) or video laparoscopic - between 1978-2007 were included. Nineteen received pre-operative alpha-blockers. Intra-operative hemodynamic data analysed were: maximum and minimum mean arterial blood pressure (MABP), no. of severe hypertensive (systolic BP >200 mmHg) and hypotensive episodes (MABP <60 mmHg), maximum and minimum heart rate (HR), no. of episodes of tachycardia and bradycardia, need to receive iv intra-operative treatment for hypertension and hypotension and the volume of fluids administered during surgery. Patients were 39.4+/-14.4-yr-old, 66% women. Intra-operative hemodynamic parameters were not different in patients submitted to open or video laparoscopic resection. Maximum intraoperative HR and the percentage of patients with HR>100 beats/min were higher in patients without pre-operative alpha- blocker treatment (no.=8). Pre-operative urinary vanylmandelic acid was positively associated with intra-operative maximum MABP (r=0.535, p=0.047) and with maximum transoperative systolic BP (r=0.805, p=0.016). Pre-operative urinary catecholamine (Pearson correlation r=0.575, p=0.03) and vanylmandelic acid (Pearson correlation r=0.605, p=0.04) levels were associated with maximum intra- operative MABP, adjusted for the presence of pheochromocytoma symptoms, surgical approach and pre-operative alpha-blockers. In conclusion, the degree of pre-operative catecholamine secretion was the most important aspect of transoperative BP control.

20p12.3 microdeletion predisposes to Wolff-Parkinson-White syndrome with variable neurocognitive deficits

BACKGROUND

Wolff-Parkinson-White syndrome (WPW) is a bypass re-entrant tachycardia that results from an abnormal connection between the atria and ventricles. Mutations in PRKAG2 have been described in patients with familial WPW syndrome and hypertrophic cardiomyopathy. Based on the role of bone morphogenetic protein (BMP) signalling in the development of annulus fibrosus in mice, it has been proposed that BMP signalling through the type 1a receptor and other downstream components may play a role in pre-excitation.

METHODS AND RESULTS

Using the array comparative genomic hybridisation (CGH), we identified five individuals with non-recurrent deletions of 20p12.3. Four of these individuals had WPW syndrome with variable dysmorphisms and neurocognitive delay. With the exception of one maternally inherited deletion, all occurred de novo, and the smallest of these harboured a single gene, BMP2. In two individuals with additional features of Alagille syndrome, deletion of both JAG1 and BMP2 were identified. Deletion of this region has not been described as a copy number variant in the Database of Genomic Variants and has not been identified in 13 321 individuals from other cohort examined by array CGH in our laboratory.

CONCLUSIONS

Our findings demonstrate a novel genomic disorder characterised by deletion of BMP2 with variable cognitive deficits and dysmorphic features and show that individuals bearing microdeletions in 20p12.3 often present with WPW syndrome.

The role of K121Q ENPP1 polymorphism in diabetes mellitus and its complications

The aim of the present study was to analyze the frequency of K121Q polymorphism in the ENPP1 gene of Brazilian subjects according to ethnic origin and to determine its possible association with diabetes mellitus (DM) and/or diabetic complications. A cross-sectional study was conducted on 1027 type 2 DM patients and 240 anonymous blood donors (BD). Ethnicity was classified based on self-report of European and African descent. The Q allele frequency was increased in African descendant type 2 DM patients (KK = 25.9%, KQ = 48.2%, and QQ = 25.9%) and BD (KK = 22.0%, KQ = 53.8%, and QQ = 24.2%) compared to European descendant type 2 DM patients (KK = 62.7%, KQ = 33.3%, and QQ = 4.1%) and BD (KK = 61.0%, KQ = 35.6%, and QQ = 3.4%). However, there was no difference in genotype distribution or Q allele frequency between diabetic and non-diabetic subjects (European descendants: DM = 0.21 vs BD = 0.21, P = 0.966, and African descendants: DM = 0.50 vs BD = 0.51, P = 0.899). In addition, there were no differences in clinical, laboratory or insulin resistance indices among the three genotypes. The prevalence of DM complications was also similar. In conclusion, K121Q polymorphism is more common among Afro-Brazilian descendants regardless of glycemic status or insulin sensitivity indices. Likewise, insulin sensitivity and DM chronic complications appear not to be related to the polymorphism in this sample.

A phase I study of lapatinib and topotecan in patients with solid tumors

3598

Background: Drug resistance to topotecan can be the result of BCRP/ABCG2 expression. BCRP is a member of the ABC transporter family that pumps anticancer drugs out of the cell. Lapatinib is a potent and selective dual inhibitor of epidermal growth factor receptor (EGFR or ErbB1) and ErbB2 (Her2/Neu). 4-aminoquinazoline tyrosine kinase inhibitors have been shown to enhance the cytotoxicity of topotecan through inhibition of BCRP-mediated drug efflux in cancer cells. Methods: Thirty-seven patients with advanced stage cancers were enrolled at escalating dose levels of lapatinib and topotecan in cohorts IA, IB and IIB (MTD). Treatment schedule included lapatinib (750 - 1500 mg/d) daily for 21 (cohort IA) or 28 days (cohort IB) and topotecan (2.4 - 4.0 mg/ m2), days 1, 8 and 15; cycles were repeated every 28 days. Three patients were treated at each dose level, 18 on cohort IA, 9 on cohort IB and 10 at MTD (cohort IIB). Assessments of toxicity were performed with each cycle and clinical response was determined per RECIST criteria every other cycle. Results: The MTD for cohorts IA and IB was reached at a dose of 1250 mg of lapatinib and 3.2 mg/m2 of IV topotecan on days 1, 8 and 15. No DLT were seen during the dose escalation stage of cohorts IA and IB. Ten patients were enrolled at the MTD. There were no grade 4+ events. Thirteen grade 3+ events, considered to be related to treatment, were seen in 6 patients. The most common grade 3+ toxicities included dehydration (2) diarrhea (2), nausea (3), vomiting (2), neutropenia (1), thrombocytopenia (1), and fatigue (1). No abnormalities in left ventricular ejection fraction were noted. Stable disease was seen in 46% of the 37 patients. Conclusions: The combination of lapatinib and topotecan is a well-tolerated regimen. The MTD for the combination is lapatinib 1,250 mg orally once daily for 21 or 28 days and topotecan 3.2 mg/m2 on days 1, 8 and 15. Pharmacokinetic analysis for drug interaction will be available for presentation at the meeting. Supported in part by GSK and Mayo Clinic

No significant financial relationships to disclose.