Omental preadipocytes stimulate matrix remodeling and IGF signaling to support ovarian cancer metastasis.

Ovarian cancer can metastasize to the omentum, which is associated with a complex tumor microenvironment. Omental stromal cells facilitate ovarian cancer colonization by secreting cytokines and growth factors. Improved understanding of the tumor supportive functions of specific cell populations in the omentum could identify strategies to prevent and treat ovarian cancer metastasis. Here, we showed that omental preadipocytes enhance the tumor initiation capacity of ovarian cancer cells. Secreted factors from preadipocytes supported cancer cell viability during nutrient and isolation stress and enabled prolonged proliferation. Co-culturing with pre-adipocytes led to upregulation of genes involved in extracellular matrix (ECM) organization, cellular response to stress, and regulation of insulin-like growth factor (IGF) signaling in ovarian cancer cells. IGF-1 induced ECM genes and increased alternative NF-κB signaling by activating RelB. Inhibiting the IGF-1 receptor (IGF1R) initially increased tumor omental adhesion but decreased growth of established preadipocyte-induced subcutaneous tumors as well as established intraperitoneal tumors. Together, this study shows that omental preadipocytes support ovarian cancer progression, which has implications for targeting metastasis.

Robotic hernia repair with the novel HUGO robot system - An initial experience from a tertiary centre.

BACKGROUND: Hernia repair using robotic platforms has been on the rise in the last decade. The HUGO robotic-assisted surgery (RAS) system, introduced in 2021, is a new addition to the field. In this study, we share our experience with this innovative system for the management of ventral and groin hernias. PATIENTS AND METHODS: The aim of our study was to evaluate the feasibility and safety of using the HUGO robotic platform for hernia surgeries. We conducted a retrospective analysis of all hernia surgeries performed with the HUGO system over a 1-year study period. The study assessed various aspects, including the technical manoeuvres of the robotic system, duration of surgery, length of hospital stay, post-operative pain levels and 30-day morbidity rates. RESULTS AND CONCLUSIONS: A total of seven hernia surgeries were performed using the HUGO system, including five ventral hernias and two groin hernias. The average duration of surgery was 128 min, with a docking duration of 22.8 min. Notably, there were no intraoperative or post-operative adverse events reported during these procedures. The HUGO system features an open console that provides a panoramic view of the operating room. In addition, the individual arm carts can be easily manoeuvred around the operating table, facilitating improved access to multiple quadrants during surgery. In our case series, Robotic hernia repair using the HUGO system has demonstrated feasibility, with post-operative outcomes comparable to traditional approaches. This innovative system serves as an additional tool in the armamentarium of hernia surgery and shows potential for improving surgical outcomes. However, further investigation through large-scale prospective studies is necessary to comprehensively evaluate its efficacy and benefits.

Flotillin-2 regulates epidermal growth factor receptor activation, degradation by Cbl-mediated ubiquitination, and cancer growth.

Epidermal growth factor receptor (EGFR) signaling is frequently dysregulated in various cancers. The ubiquitin ligase Casitas B-lineage lymphoma proto-oncogene (Cbl) regulates degradation of activated EGFR through ubiquitination and acts as an adaptor to recruit proteins required for trafficking. Here, we used stable isotope labeling with amino acids in cell culture mass spectrometry to compare Cbl complexes with or without epidermal growth factor (EGF) stimulation. We identified over a hundred novel Cbl interactors, and a secondary siRNA screen found that knockdown of Flotillin-2 (FLOT2) led to increased phosphorylation and degradation of EGFR upon EGF stimulation in HeLa cells. In PC9 and H441 cells, FLOT2 knockdown increased EGF-stimulated EGFR phosphorylation, ubiquitination, and downstream signaling, reversible by EGFR inhibitor erlotinib. CRISPR knockout (KO) of FLOT2 in HeLa cells confirmed EGFR downregulation, increased signaling, and increased dimerization and endosomal trafficking. Furthermore, we determined that FLOT2 interacted with both Cbl and EGFR. EGFR downregulation upon FLOT2 loss was Cbl dependent, as coknockdown of Cbl and Cbl-b restored EGFR levels. In addition, FLOT2 overexpression decreased EGFR signaling and growth. Overexpression of wildtype (WT) FLOT2, but not the soluble G2A FLOT2 mutant, inhibited EGFR phosphorylation upon EGF stimulation in HEK293T cells. FLOT2 loss induced EGFR-dependent proliferation and anchorage-independent growth. Lastly, FLOT2 KO increased tumor formation and tumor volume in nude mice and NSG mice, respectively. Together, these data demonstrated that FLOT2 negatively regulated EGFR activation and dimerization, as well as its subsequent ubiquitination, endosomal trafficking, and degradation, leading to reduced proliferation in vitro and in vivo.

TWEAK-Fn14-RelB Signaling Cascade Promotes Stem Cell-like Features that Contribute to Post-Chemotherapy Ovarian Cancer Relapse.

Disease recurrence in high-grade serous ovarian cancer may be due to cancer stem-like cells (CSC) that are resistant to chemotherapy and capable of reestablishing heterogeneous tumors. The alternative NF-κB signaling pathway is implicated in this process; however, the mechanism is unknown. Here we show that TNF-like weak inducer of apoptosis (TWEAK) and its receptor, Fn14, are strong inducers of alternative NF-κB signaling and are enriched in ovarian tumors following chemotherapy treatment. We further show that TWEAK enhances spheroid formation ability, asymmetric division capacity, and expression of SOX2 and epithelial-to-mesenchymal transition genes VIM and ZEB1 in ovarian cancer cells, phenotypes that are enhanced when TWEAK is combined with carboplatin. Moreover, TWEAK in combination with chemotherapy induces expression of the CSC marker CD117 in CD117- cells. Blocking the TWEAK-Fn14-RelB signaling cascade with a small-molecule inhibitor of Fn14 prolongs survival following carboplatin chemotherapy in a mouse model of ovarian cancer. These data provide new insights into ovarian cancer CSC biology and highlight a signaling axis that should be explored for therapeutic development. IMPLICATIONS: This study identifies a unique mechanism for the induction of ovarian cancer stem cells that may serve as a novel therapeutic target for preventing relapse.

Solid Pseudopapillary Neoplasm of the Pancreas: Unraveling Insights from a Single Institutional Study Emphasizing Preoperative Diagnosis of a Rare Tumor.

Aim: Solid pseudopapillary neoplasm (SPN), a slow-growing pancreatic tumor with a vague clinical presentation and non-specific radiological features, is rather uncommon. We share our experience emphasizing on preoperative diagnosis and the correlation with final histopathological examination. Materials and methods: This is a retrospective analysis of the 468 patients who underwent pancreas-related surgery at our institution between January 2013 and July 2022. Demographic characteristics, symptoms at presentation, preoperative serum calcium carbohydrate antigen (CA 19-9), lesion characteristics on cross-sectional diagnostic imaging, surgical technique, complications in postoperative period, length of stay, histopathological features, and 3-year follow-up findings of the patients with SPN of pancreas were evaluated. Results: The male-to-female ratio was 1:11 and the mean age at presentation was 33.3 ± 9.5 years. Upper abdomen discomfort was the most common presenting complaint (91%). And five patients had findings suggestive of SPN on preoperative CECT abdomen, and the remaining six individuals were diagnosed solely based on final histological examination. The tumor's median diameter was 5.6 cm (range, 4.1-7.9). The distal body and tail of pancreas was the most common location (63%), followed by the head (36%), and was managed with distal pancreatectomy with or without spleen preservation and Whipple's procedure, respectively. One patient developed grade III Clavien-Dindo complication. The average length of in-hospital stay was 8.27±2.72 days. None of the patients had recurrence on follow-up. Conclusion: Solid pseudopapillary neoplasm of the pancreas is often misdiagnosed preoperatively. Endoscopic ultrasound-guided FNA with IHC will be beneficial to diagnose it preoperatively especially in small-sized tumors with atypical features. Complete surgical resection with adequate margins without routine lymphadenectomy is curative in resectable tumors. How to cite this article: Jayapal L, Kumar SR, Jebakumar GS, et al. Solid Pseudopapillary Neoplasm of the Pancreas: Unraveling Insights from a Single Institutional Study Emphasizing Preoperative Diagnosis of a Rare Tumor. Euroasian J Hepato-Gastroenterol 2023;13(2):50-54.

Mitochondrial Matrix Protease ClpP Agonists Inhibit Cancer Stem Cell Function in Breast Cancer Cells by Disrupting Mitochondrial Homeostasis.

Mitochondria are multifaceted organelles which are important for bioenergetics, biosynthesis and signaling in metazoans. Mitochondrial functions are frequently altered in cancer to promote both the energy and the necessary metabolic intermediates for biosynthesis required for tumor growth. Cancer stem cells (CSCs) contribute to chemotherapy resistance, relapse, and metastasis. Recent studies have shown that while non-stem, bulk cancer cells utilize glycolysis, breast CSCs are more dependent on oxidative phosphorylation (OxPhos) and therefore targeting mitochondria may inhibit CSC function. We previously reported that small molecule ONC201, which is an agonist for the mitochondrial caseinolytic protease (ClpP), induces mitochondrial dysfunction in breast cancer cells. In this study, we report that ClpP agonists inhibit breast cancer cell proliferation and CSC function in vitro and in vivo. Mechanistically, we found that OxPhos inhibition downregulates multiple pathways required for CSC function, such as the mevalonate pathway, YAP, Myc, and the HIF pathway. ClpP agonists showed significantly greater inhibitory effect on CSC functions compared with other mitochondria-targeting drugs. Further studies showed that ClpP agonists deplete NAD(P)+ and NAD(P)H, induce redox imbalance, dysregulate one-carbon metabolism and proline biosynthesis. Downregulation of these pathways by ClpP agonists further contribute to the inhibition of CSC function. In conclusion, ClpP agonists inhibit breast CSC functions by disrupting mitochondrial homeostasis in breast cancer cells and inhibiting multiple pathways critical to CSC function. Significance: ClpP agonists disrupt mitochondrial homeostasis by activating mitochondrial matrix protease ClpP. We report that ClpP agonists inhibit cell growth and cancer stem cell functions in breast cancer models by modulating multiple metabolic pathways essential to cancer stem cell function.

Durability of Clinical and Quality-of-Life Outcomes of Closed-Loop Spinal Cord Stimulation for Chronic Back and Leg Pain: A Secondary Analysis of the Evoke Randomized Clinical Trial.

Importance: Chronic pain is debilitating and profoundly affects health-related quality of life. Spinal cord stimulation (SCS) is a well-established therapy for chronic pain; however, SCS has been limited by the inability to directly measure the elicited neural response, precluding confirmation of neural activation and continuous therapy. A novel SCS system measures the evoked compound action potentials (ECAPs) to produce a real-time physiological closed-loop control system. Objective: To determine whether ECAP-controlled, closed-loop SCS is associated with better outcomes compared with fixed-output, open-loop SCS at 24 months following implant. Design, Setting, and Participants: The Evoke study was a double-blind, randomized, controlled, parallel arm clinical trial with 36 months of follow-up. Participants were enrolled from February 2017 to 2018, and the study was conducted at 13 US investigation sites. SCS candidates with chronic, intractable back and leg pain refractory to conservative therapy, who consented, were screened. Key eligibility criteria included overall, back, and leg pain visual analog scale score of 60 mm or more; Oswestry Disability Index score of 41 to 80; stable pain medications; and no previous SCS. Analysis took place from October 2020 to April 2021. Interventions: ECAP-controlled, closed-loop SCS was compared with fixed-output, open-loop SCS. Main Outcomes and Measures: Reported here are the 24-month outcomes of the trial, which include all randomized patients in the primary and safety analyses. The primary outcome was a reduction of 50% or more in overall back and leg pain assessed at 3 and 12 months (previously published). Results: Of 134 randomized patients, 65 (48.5%) were female and the mean (SD) age was 55.2 (10.6) years. At 24 months, significantly more closed-loop than open-loop patients were responders (≥50% reduction) in overall pain (53 of 67 [79.1%] in the closed-loop group; 36 of 67 [53.7%] in the open-loop group; difference, 25.4% [95% CI, 10.0%-40.8%]; P = .001). There was no difference in safety profiles between groups (difference in rate of study-related adverse events: 6.0 [95% CI, -7.8 to 19.7]). Improvements were also observed in health-related quality of life, physical and emotional functioning, and sleep, in parallel with opioid reduction or elimination. Objective neurophysiological measurements substantiated the clinical outcomes and provided evidence of activation of inhibitory pain mechanisms. Conclusions and Relevance: ECAP-controlled, closed-loop SCS, which elicited a more consistent neural response, was associated with sustained superior pain relief at 24 months, consistent with the 3- and 12-month outcomes.

Characterization of SOX2, OCT4 and NANOG in Ovarian Cancer Tumor-Initiating Cells.

The identification of tumor-initiating cells (TICs) has traditionally relied on surface markers including CD133, CD44, CD117, and the aldehyde dehydrogenase (ALDH) enzyme, which have diverse expression across samples. A more reliable indication of TICs may include the expression of embryonic transcription factors that support long-term self-renewal, multipotency, and quiescence. We hypothesize that SOX2, OCT4, and NANOG will be enriched in ovarian TICs and may indicate TICs with high relapse potential. We evaluated a panel of eight ovarian cancer cell lines grown in standard 2-D culture or in spheroid-enriching 3-D culture, and correlated expression with growth characteristics, TIC marker expression, and chemotherapy resistance. RNA-sequencing showed that cell cycle regulation pathways involving SOX2 were elevated in 3-D conditions. HGSOC lines had longer doubling-times, greater chemoresistance, and significantly increased expression of SOX2, OCT4, and NANOG in 3-D conditions. CD117+ or ALDH+/CD133+ cells had increased SOX2, OCT4, and NANOG expression. Limiting dilution in in vivo experiments implicated SOX2, but not OCT4 or NANOG, with early tumor-initiation. An analysis of patient data suggested a stronger role for SOX2, relative to OCT4 or NANOG, for tumor relapse potential. Overall, our findings suggest that SOX2 may be a more consistent indicator of ovarian TICs that contribute to tumor repopulation following chemotherapy. Future studies evaluating SOX2 in TIC biology will increase our understanding of the mechanisms that drive ovarian cancer relapse.

Stifle joint osteoarthritis at the time of diagnosis of cranial cruciate ligament injury is higher in Boxers and in dogs weighing more than 35 kilograms.

Osteoarthritis is a ubiquitous disease in dogs. The purpose of this retrospective study was to characterize the severity and distribution of osteoarthritis (OA) within the joint and to identify differences among dog breeds in the severity of OA in the cranial cruciate ligament (CCL)-deficient stifle joint. Radiographs of 240 stifles from 51 Boxers, 66 German Shepherds, 100 Labrador Retrievers, and 23 Siberian Huskies with confirmed CCL rupture were included. Radiographs of the stifle joint were evaluated and OA severity was graded at 33 sites within and around the joint, and patella alta was graded as present or absent for a potential total stifle OA score of 100. Osteophyte size was correlated to OA severity score. Total OA scores were calculated and compared within and between breeds globally as well as at each joint site. Dogs weighing >35 kg had a higher total OA score than those weighing <35 kg. Osteoarthritis scores were highest at the apical patella, proximolateral tibia, and sesamoid bones, corresponding to the proximal, lateral, and caudal aspects of the joint, respectively. No statistically significant differences were found among the mean OA scores of various stifle joint regions. Boxer dogs had a higher total OA score than other breeds. We concluded that dogs have a consistent distribution pattern of OA within the stifle joint after CCL injury. Radiographic OA is more severe in the proximal, lateral, and caudal aspects of the joint. Boxers had more severe OA than the other breeds evaluated in the study.

MEDI3039, a novel highly potent tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptor 2 agonist, causes regression of orthotopic tumors and inhibits outgrowth of metastatic triple-negative breast cancer.

BACKGROUND: TNF-related apoptosis-inducing ligand (TRAIL) receptor agonists are attractive anti-tumor agents because of their capability to induce apoptosis in cancer cells by activating death receptors (DR) 4 and 5 with little toxicity against normal cells. Despite an attractive mechanism of action, previous clinical efforts to use TRAIL receptor agonists have been unsuccessful. In this study, we examined MEDI3039, a highly potent multivalent DR5 agonist, in breast cancer cell lines and in vivo models. METHODS: As in vitro model systems, we used 19 breast cancer cell lines that are categorized into four subtypes: ER+, HER2 amplified, basal A (triple-negative breast cancer) TNBC, and basal B TNBC. Cell viability was analyzed by MTS and RealTime live/dead assays. As in vivo model systems, MDA-MB231T orthotopic primary tumor growth in the mammary fat pad (MFP) and two experimental lung metastasis models were used. The effect of MEDI3039 on MFP tumors was assessed with immunohistochemical analysis. Lung metastases were analyzed with Bouin's and H&E staining. RESULTS: MEDI3039 killed multiple breast cancer cell lines, but the sensitivity varied among different subtypes. Sensitivity was basal B TNBC >> basal A TNBC > HER2 amplified > ER+ (average IC50 = 1.4, 203, 314, 403 pM, respectively). While the pattern of relative sensitivity was similar to GST-TRAIL in most cell lines, MEDI3039 was at least two orders of magnitude more potent compared with GST-TRAIL. In the MFP model, weekly treatment with 0.1 or 0.3 mg/kg MEDI3039 for 5 weeks inhibited tumor growth by 99.05% or 100% (median), respectively, compared with the control group, and extended animal survival (p = 0.08 or p = 0.0032 at 0.1 or 0.3 mg/kg, respectively). MEDI3039-induced caspase activation was confirmed in tumors grown in MFP (p < 0.05). In an experimental pulmonary metastasis model, MEDI3039 significantly suppressed outgrowth of surface (p < 0.0001) and microscopic metastases (p < 0.05). In an established lung metastasis model, MEDI3039 significantly inhibited growth of metastases (p < 0.01 in surface [> 4 mm], p < 0.01 in tumor percentage) and extended animal survival (p < 0.0001). CONCLUSION: MEDI3039 is a potent DR5 agonist in breast cancer cells in vitro and in vivo and has potential as a cancer drug in breast cancer patients, especially those with basal B TNBC.

Refinement, Reduction, and Replacement (3R) Strategies in Preclinical Testing of Medical Devices.

The U.S. Food and Drug Administration Center for Devices and Radiological Health (FDA/CDRH) has recently published several in vivo test guidance documents that mention refinements, reductions, or replacement animal testing strategies to facilitate the leveraging of data from large animal safety tests for conventional rodent testing. In response to the recently enacted Food and Drug Administration Safety and Innovation Act Section 907, which facilitates expedited access to novel therapies commonly described as Breakthrough Therapy Designation, FDA/CDRH has discussed efficient regulatory strategies for first-in-human investigation, including early feasibility study guidance. Large gains in humane care and translational research could also be attained by examples in FDA's Guidance for the Use of International Organization for Standardization 10993-1, which states that large animal safety studies may be considered as replacement rodent tests if the scientific principles, methods, and end points (SPME) are considered and applied. This article discusses SPME for the replacement of conventional rodent testing by the inclusion and integration of clinical, diagnostic, and pathologic data obtained from well-designed large animal studies. The recommendations include consideration for study designs that utilize methods for an overall more comprehensive interrogation of animal systems.

ONC201 kills breast cancer cells in vitro by targeting mitochondria.

We report a novel mechanism of action of ONC201 as a mitochondria-targeting drug in cancer cells. ONC201 was originally identified as a small molecule that induces transcription of TNF-related apoptosis-inducing ligand (TRAIL) and subsequently kills cancer cells by activating TRAIL death receptors. In this study, we examined ONC201 toxicity on multiple human breast and endometrial cancer cell lines. ONC201 attenuated cell viability in all cancer cell lines tested. Unexpectedly, ONC201 toxicity was not dependent on either TRAIL receptors nor caspases. Time-lapse live cell imaging revealed that ONC201 induces cell membrane ballooning followed by rupture, distinct from the morphology of cells undergoing apoptosis. Further investigation found that ONC201 induces phosphorylation of AMP-dependent kinase and ATP loss. Cytotoxicity and ATP depletion were significantly enhanced in the absence of glucose, suggesting that ONC201 targets mitochondrial respiration. Further analysis indicated that ONC201 indirectly inhibits mitochondrial respiration. Confocal and electron microscopic analysis demonstrated that ONC201 triggers mitochondrial structural damage and functional impairment. Moreover, ONC201 decreased mitochondrial DNA (mtDNA). RNAseq analysis revealed that ONC201 suppresses expression of multiple mtDNA-encoded genes and nuclear-encoded mitochondrial genes involved in oxidative phosphorylation and other mitochondrial functions. Importantly, fumarate hydratase deficient cancer cells and multiple cancer cell lines with reduced amounts of mtDNA were resistant to ONC201. These results indicate that cells not dependent on mitochondrial respiration are ONC201-resistant. Our data demonstrate that ONC201 kills cancer cells by disrupting mitochondrial function and further suggests that cancer cells that are dependent on glycolysis will be resistant to ONC201.

Pathogenesis of Vertebral Anterior Wedge Deformity: A 2-Stage Process?

STUDY DESIGN: Biomechanical and radiographical study on cadaveric spines. OBJECTIVE: To explain the pathogenesis of vertebral "anterior wedge" deformity, which causes senile kyphosis. SUMMARY OF BACKGROUND DATA: This deformity arises with minimal trauma and is difficult to reproduce in cadaveric spines. We hypothesize that wedging is created by a 2-stage process. First, excessive loading damages a vertebral endplate and decompresses the adjacent intervertebral disc. This alters load sharing between the vertebral body cortex and trabeculae so that subsequent cyclic loading causes progressive collapse of the unsupported anterior cortex. METHODS: Thirty-four cadaveric thoracolumbar "motion segments," aged 70 to 98 years, were positioned in flexion and overloaded in compression. Physiologically reasonable cyclic compressive loading was then applied to each flexed specimen, at progressively higher loads, for up to 2 hours. Before and after initial overload and again after cyclic loading, the distribution of loading on the vertebra was assessed from measurements of compressive stress within the adjacent disc. These "stress profiles" were repeated in the neutral, flexed, and extended postures. Progressive vertebral body deformity was assessed radiographically. RESULTS: Compressive overload induced endplate fracture at an average force of 2.31 kN. There was minimal anterior wedging, but pressure in the adjacent disc nucleus (in flexion) fell by an average of 55% and neural arch load bearing increased by 166%. Subsequent cyclic loading exaggerated these changes and concentrated compressive stress within the anterior annulus. After both stages, height of the anterior and posterior vertebral cortexes was reduced by 32% and 12%, respectively, so that anterior wedging of the vertebral body increased from 5.0° to 11.4° on average. All changes were highly significant (P < 0.001). CONCLUSION: Anterior wedge deformities can be created consistently by a 2-stage process involving initial endplate damage, followed by progressive collapse of the anterior cortex. Detecting initial endplate damage may be important to minimize vertebral deformity in patients with osteoporosis. LEVEL OF EVIDENCE: N/A.

From caveman companion to medical innovator: genomic insights into the origin and evolution of domestic dogs.

The phenotypic and behavioral diversity of the domestic dog has yet to be matched by any other mammalian species. In their current form, which comprises more than 350 populations known as breeds, there is a size range of two orders of magnitude and morphological features reminiscent of not only different species but also different phylogenetic families. The range of both appearance and behavior found in the dog is the product of millennia of human interference, and though humans created the diversity it remains a point of fascination to both lay and scientific communities. In this review we summarize the current understanding of the history of dog domestication based on molecular data. We will examine the ways that canine genetic and genomic studies have evolved and look at examples of dog genetics in the light of human disease.

Genome annotation by shotgun inactivation of a native gene in hemizygous cells: application to BRCA2 with implication of hypomorphic variants.

The greatest interpretive challenge of modern medicine may be to functionally annotate the vast variation of human genomes. Demonstrating a proposed approach, we created a library of BRCA2 exon 27 shotgun-mutant plasmids including solitary and multiplex mutations to generate human knockin clones using homologous recombination. This 55-mutation, 13-clone syngeneic variance library (SyVaL) comprised severely affected clones having early-stop nonsense mutations, functionally hypomorphic clones having multiple missense mutations emphasizing the potential to identify and assess hypomorphic mutations in novel proteomic and epidemiologic studies, and neutral clones having multiple missense mutations. Efficient coverage of nonessential amino acids was provided by mutation multiplexing. Severe mutations were distinguished from hypomorphic or neutral changes by chemosensitivity assays (hypersensitivity to mitomycin C and acetaldehyde), by analysis of RAD51 focus formation, and by mitotic multipolarity. A multiplex unbiased approach of generating all-human SyVaLs in medically important genes, with random mutations in native genes, would provide databases of variants that could be functionally annotated without concerns arising from exogenous cDNA constructs or interspecies interactions, as a basis for subsequent proteomic domain mapping or clinical calibration if desired. Such gene-irrelevant approaches could be scaled up for multiple genes of clinical interest, providing distributable cellular libraries linked to public-shared functional databases.

Is kyphoplasty better than vertebroplasty at restoring form and function after severe vertebral wedge fractures?

BACKGROUND CONTEXT: The vertebral augmentation procedures, vertebroplasty and kyphoplasty, can relieve pain and facilitate mobilization of patients with osteoporotic vertebral fractures. Kyphoplasty also aims to restore vertebral body height before cement injection and so may be advantageous for more severe fractures. PURPOSE: The purpose of this study was to compare the ability of vertebroplasty and kyphoplasty to restore vertebral height, shape, and mechanical function after severe vertebral wedge fractures. STUDY DESIGN/SETTING: This is a biomechanical and radiographic study using human cadaveric spines. METHODS: Seventeen pairs of thoracolumbar "motion segments" from cadavers aged 70-98 years were injured, in a two-stage process involving flexion and compression, to create severe anterior wedge fractures. One of each pair underwent vertebroplasty and the other kyphoplasty. Specimens were then compressed at 1 kN for 1 hour to allow consolidation. Radiographs were taken before and after injury, after treatment, and after consolidation. At these same time points, motion segment compressive stiffness was assessed, and intervertebral disc "stress profiles" were obtained to characterize the distribution of compressive stress on the vertebral body and neural arch. RESULTS: On average, injury reduced anterior vertebral body height by 34%, increased its anterior wedge angle from 5.0° to 11.4°, reduced intradiscal (nucleus) pressure and motion segment stiffness by 96% and 44%, respectively, and increased neural arch load bearing by 57%. Kyphoplasty caused 97% of the anterior height loss to be regained immediately, although this reduced to 79% after consolidation. Equivalent gains after vertebroplasty were significantly lower: 59% and 47%, respectively (p<.001). Kyphoplasty reduced vertebral wedging more than vertebroplasty (p<.02). Intradiscal pressure, neural arch load bearing, and motion segment compressive stiffness were restored significantly toward prefracture values after both augmentation procedures, even after consolidation, but these mechanical effects were similar for kyphoplasty and vertebroplasty. CONCLUSIONS: After severe vertebral wedge fractures, vertebroplasty and kyphoplasty were equally effective in restoring mechanical function. However, kyphoplasty was better able to restore vertebral height and reverse wedge deformity.

PIK3CA and AKT1 mutations have distinct effects on sensitivity to targeted pathway inhibitors in an isogenic luminal breast cancer model system.

PURPOSE: Activating mutations in the phosphoinositide-3-kinase (PI3K)/AKT/mTOR pathway are present in the majority of breast cancers and therefore are a major focus of drug development and clinical trials. Pathway mutations have been proposed as predictive biomarkers for efficacy of PI3K-targeted therapies. However, the precise contribution of distinct PI3K pathway mutations to drug sensitivity is unknown. EXPERIMENTAL DESIGN: We describe the creation of a physiologic human luminal breast cancer cell line model to study the phenotype of these mutations using the MCF-7 cell line. We used somatic cell gene targeting to "correct" PIK3CA E545K-mutant alleles in MCF-7 cells to wild-type sequence. The AKT1 E17K hotspot mutation was knocked in on this wild-type background. RESULTS: Loss of mutant PIK3CA dramatically reduced phosphorylation of AKT proteins and several known AKT targets, but other AKT target proteins and downstream effectors of mTOR were not affected. PIK3CA wild-type cells exhibited reduced proliferation in vitro and in vivo. Knockin of the AKT1 E17K hotspot mutation on this PIK3CA wild-type background restored pathway signaling, proliferation, and tumor growth in vivo. PIK3CA, but not AKT1 mutation, increased sensitivity to the PI3K inhibitor GDC-0941 and the allosteric AKT inhibitor MK-2206. CONCLUSIONS: AKT1 E17K is a bona fide oncogene in a human luminal breast cancer context. Distinct PI3K pathway mutations confer differential sensitivity to drugs targeting the pathway at different points and by distinct mechanisms. These findings have implications for the use of tumor genome sequencing to assign patients to targeted therapies.

Biological clues to potent DNA-damaging activities in food and flavoring.

Population differences in age-related diseases and cancer could stem from differences in diet. To characterize DNA strand-breaking activities in selected foods/beverages, flavorings, and some of their constituent chemicals, we used p53R cells, a cellular assay sensitive to such breaks. Substances testing positive included reference chemicals: quinacrine (peak response, 51×) and etoposide (33×); flavonoids: EGCG (19×), curcumin (12×), apigenin (9×), and quercetin (7×); beverages: chamomile (11×), green (21×), and black tea (26×) and coffee (3-29×); and liquid smoke (4-28×). Damage occurred at dietary concentrations: etoposide near 5µg/ml produced responses similar to a 1:1000 dilution of liquid smoke, a 1:20 dilution of coffee, and a 1:5 dilution of tea. Pyrogallol-related chemicals and tannins are present in dietary sources and individually produced strong activity: pyrogallol (30×), 3-methoxycatechol (25×), gallic acid (21×), and 1,2,4-benzenetriol (21×). From structure-activity relationships, high activities depended on specific orientations of hydroxyls on the benzene ring. Responses accompanied cellular signals characteristic of DNA breaks such as H2AX phosphorylation. Breaks were also directly detected by comet assay. Cellular toxicological effects of foods and flavorings could guide epidemiologic and experimental studies of potential disease risks from DNA strand-breaking chemicals in diets.

Age distribution, polyps and rectal cancer in the Egyptian population-based cancer registry.

AIM: To describe the clinical and epidemiologic profiles of the disease and to compare the findings with those generated from the previous hospital-based studies. METHODS: The Gharbiah cancer registry is the only population-based cancer registry in Egypt since 1998. We analyzed the data of all colorectal cancer patients included in the registry for the period of 1999-2007. All medical records of the 1364 patients diagnosed in Gharbiah during the study period were retrieved and the following information abstracted: age, residence, diagnosis date, grade, stage, topology, clinical characteristics, and histology variables. Egyptian census data for 1996 and 2006 were used to provide the general population's statistics on age, sex, residence and other related demographic factors. In addition to age- and sex-specific incidence rate analyses, we analyze the data to explore the incidence distribution by rural-urban differences among the 8 districts of the province. We also compared the incidence rates of Gharbiah to the rates of the Surveillance Epidemiology and End Results (SEER) data of the United States. RESULTS: Over the 9 year-period, 1364 colorectal cancer cases were included. The disease incidence under age 40 years was relatively high (1.3/10(5)) while the incidence in the age groups 40 and over was very low (12.0/10(5), 19.4/10(5) and 21.2/10(5) in the age groups 40-59 years, 60-69 years and > 70 years, respectively). The vast majority of tumors (97.2%) had no polyps and 37.2% of the patients presented with primary lesions in the rectum. Colorectal cancer was more common in patients from urban (55%) than rural (45%) areas. Regional differences in colon and rectal cancer incidence in the 8 districts of the study province may reflect different etiologic patterns in this population. The registry data of Egypt shows a slightly higher incidence of colorectal cancer than the United States in subjects under age 40 years. The results also shows significantly lower incidence of colorectal cancer in subjects over age 40 years compared to the same age group in the United States SEER. CONCLUSION: Low rate of polyps, low incidence in older subjects, and high rate of rectal cancer in Egypt. Future studies should explore clinical and molecular disease patterns.

Clinical profile, BRCA2 expression, and the androgen receptor CAG repeat region in Egyptian and Moroccan male breast cancer patients.

INTRODUCTION: Male breast cancer (MBC) is a rare disease. Rates of MBC in Northern Africa vary by region. The age-standardized incidence for MBC is higher in Morocco than in Egypt, and the Egyptian rate is similar to the U.S of approximately 1/10(5)This study aimed at investigating the clinical and molecular characteristics of MBC in Egypt and Morocco. METHODS: This case-case study included 211 cases from Egypt and 132 from Morocco. Tumor tissues were available for 47 Egyptian and 18 Moroccan patients. Medical record information was abstracted for patients' demographics, medical history, and treatment. BRCA2 protein expression status was examined in Egyptian and Moroccan tumors. Androgen receptor CAG repeat length was analyzed using the tissue samples in Egyptian MBC tumors and controls. Limited amount of tissues from Morocco did not allow for the analysis of CAG repeats. RESULTS: Egyptian MBC patients had a significantly lower age at diagnosis (Egypt: 57.5 ± 15.1, Morocco: 63.9 ± 14.4, P=0.0002) and a higher prevalence of liver cirrhosis (Egypt: 28.0%, Morocco: 0.8%, P=< 0.0001). MBC patients also had higher tumor grades [I (0.9%), II (81.0%), III (18.1%)] in Egypt vs. [I (10.7%), II (81.0%), III (8.3%)] in Morocco (P=0.0017). The clinical and molecular characteristics of the groups from the 2 countries did not significantly differ. There was no significant difference with respect to BRCA2 expression amongst countries (Egypt: 28.9% non-wild type, Morocco: 27.8% non-wild type, P=0.9297) or CAG lengths amongst BRCA2 expression types in Egyptians (Wild type: 54.6% with CAG repeat lengths of 20+, Non-wild type: 50% with CAG repeat lengths of 20+, P=0.7947). CONCLUSIONS: Differences in MBC between Egypt and Morocco are more likely due to differences in other risk factors such as consanguinity and use of xenoestrogenic pesticides.