[To highlight the evidence-based medical imaging clinical appropriateness (EB-MICA􀳏)]

The appropriate application of medical imaging is a major concern of our nation in recent years. In the year of 2020, we proposed the concept of Evidence-based Medical Imaging Clinical Appropriateness (EB-MICA^®). We preliminary evaluated the value of different kinds of medical imaging in clinical practice. A series of work had be applied in the stage of medical imaging application. It has decreased the cost of patients and medical insurance and improved the medical efficiency, providing key clues for medical policy makers objectively. It is also an important opportunity for the transformation of medical model towards the "value-based model". In the concern of appropriate medical imaging for patients with tinnitus, hearing loss and (or) vertigo, IgG4-related disease in clinical practice, experts in related academic group wrote and published three EB-MICA consensuses as reference. This work keeps promoting rational utilization of medical resource and improving the quality of clinical decision-making.

[Analysis of the associations of chemokine receptors expression on circulating Tfh2 and Th2 cells with sIgE level and disease severity in patients with AR]

Objective: To clarify the chemotactic characteristics of type 2 helper T cells (Th2 cells) and type 2 follicular helper T cells (Tfh2 cells) in peripheral blood of patients with allergic rhinitis (AR), and to explore the associations between the chemokine receptors expression and the levels of antigen-specific IgE (sIgE) and the severity of the disease. Methods: The peripheral blood mononuclear cells of 41 patients with AR (20 males and 21 females, aged 35.0 (24.5, 47.0) years) and 42 healthy controls (24 males and 18 females, aged 35.0 (24.8, 46.5) years) treated in Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from April 2017 to February 2018 were isolated. The expressions of chemokine receptor (CCR)2, CCR3, CCR4, CCR5, CCR7, CCR8, chemokine C-X3-C-motif receptor 1 (CX3CR1) and C-X-C motif receptor 4 (CXCR4) in Th2 and Tfh2 cells were explored by fluorescence activated cell sorting (FACs). The relationship between the expression of these chemokine receptors in Th2 cells and Tfh2 cells and the levels of serum sIgE and the scores of visual analogue scale (VAS) was analyzed. Graphpad prism 7.0 software was used for statistical analysis. Results: The significant differences in chemotactic characteristics between Th2 cells and Tfh2 cells in the control group were found: Th2 cells highly expressed chemokine receptors CCR2, CCR3, CCR5, CCR8 and CX3CR1, while Tfh2 cells highly expressed immune cell homing chemokine receptors CCR7 and CXCR4. AR patients, compared to the control, expressed higher levels of CCR2, CCR5 and CX3CR1 on peripheral Th2 cells(all P<0.01). At the same time, the proportion of CCR2⁺and CCR5⁺Th2 cells was positively correlated with VAS score (r value was 0.58 and 0.61, respectively, both P<0.01). In AR patients, higher expression levels of CCR7 on Tfh2 cells were detected (P<0.01), and the proportion of CCR7⁺Tfh2 cells was positively correlated with the level of serum sIgE (r=0.51, P<0.01). Conclusion: The percentage of CCR2⁺ and CCR5⁺ Th2 cells in peripheral of AR patients can reflect the severity of AR to some extent, while the percentage of CCR7⁺ Tfh2 cells is positively correlated with the level of serum sIgE.

[Promote the construction of multi-factor associated diagnosis system, improve the clinical efficiency of medical imaging]

Medical imaging is playing a more and more important role in the new diagnosis and treatment service mode, which is being optimized under the promotion of multiple factors. Based on the concept of promoting the reconstruction of medical imaging with the theories and methods of system science, this paper proposes a new paradigm of systematic diagnosis called multi-factor associated diagnosis system, explains the background, key techniques, and inherent logic of the proposed system, and prospects the application scenarios of the system in the future.

[Analysis of the anatomical features of vestibular nerve canal based on 10 μm otology CT]

Objective: To analysis the anatomical features of normal vestibular nerve canal based on 10 μm otology CT. Methods: Sixty-seven patients (103 ears) underwent 10 μm otology CT examinations in Department of Radiology, Beijing Friendship Hospital, Capital Medical University from September 2020 to March 2021 were retrospectively recruited. There were 24 males and 43 females, aged from 18 to 70 (40±17) years. According to the morphology of the inferior vestibular nerve canal, it can be divided into four types as follows: uniform straight type, curved type, ampullary type and direct connection. The anatomical variables of the superior vestibular nerve canal (external orifice, isthmus and internal orifice widths, canal length, angle with labyrinthine segment of the facial nerve) and inferior vestibular nerve canal (widths of the externaland internal orifice, canal length, angles with long axis of the vestibule and the modiolus) between the different sides, genders and canal morphologies were analyzed and compared, respectively. Results: 100% superior vestibular nerve canals and 75.7% (78/103) inferior vestibular nerve canals are clearly depicted by otology CT. The left-side ear presented with larger internal orifice diameter of the superior vestibular neve canal [(1.46±0.47) mm vs (1.31±0.41) mm], and a smaller angle between the inferior vestibular neve canal and the modiolus [(41.6±16.9)° vs (51.6±21.0)°] than the right-side ear (all P<0.05, respectively), respectively. Compared to females, males demonstrated larger internal orifice of the superior vestibular nerve canal [(1.55±0.37) mm vs (1.28±0.36) mm, P<0.05]. The uniform straight type of the inferior vestibular nerve canal was the most common type (62.1%, 64/103), followed by the direct connection (19.4%, 20/103), and the ampullary type was the least common type (4.9%, 5/103). There were significant differences in external diameter and angles with the long axis of the vestibule and the modiolus between the four morphologies of the superior vestibular nerve canal (all P<0.05, respectively). Conclusion: Ten μm otology CT is capable of depicting normal vestibular nerve canal clearly. Quantitative measurement of the normal vestibular nerve canal can provide references for the imaging diagnosis and preoperative evaluation of lesions in this area.

[Analysis of the imaging characteristics of otosclerosis based on 10 μm otology CT]

Objective: To evaluate the imaging features of otosclerosis based on10 μm otology CT. Methods: Data of 27 patients with otosclerosis (51 sides) in Beijing Friendship Hospital, Capital Medical University from October 2020 to July 2021 were retrospectively collected, including 9 males and 18 females age ffrom 22 to 70 (42±12) years. All patients underwent 10 μm otology CT examination and surgical treatment. The types, amounts and involved sites of otosclerosis were analyzed and the sensitivity of 10 μm otology CT in diagnosing otosclerosis were evaluated. Results: Fenestral type accounted for 49.0% (25/51 sides), and diffuse type accounted for 51.0% (26/51 sides),and he retrofenestral type without fenestral lesion was not seen. Single lesions accounted for 45.1% (23/51 sides) and multiple lesions accounted for 54.9% (28/51 sides). The incidence of involvement of the fissula ante fenestram and annular ligaments were both 100%. The incidence of involvement of stapes footplate, vestibule, cochlea, round window, inner auditory canal wall, facial nerve canal, stapes muscle and semicircular canal was 60.8% (31 sides), 33.3% (17/51 sides), 21.6% (11/51 sides), 17.6% (9/51 sides), 13.7% (7/51 sides), 9.8% (5/51 sides), 7.8% (4/51 sides) and 5.9% (3/51 sides), respectively. The sensitivity of 10 μm otology CT in diagnosis of otosclerosis was 100%. Conclusion: 10 μm otology CT can fully display the imaging features of otosclerosis, and has the potential to be an effective routine method for otosclerosis.

[Study on the relationship between the morphology of the isthmus of the vestibular aqueduct and Meniere's disease based on 10 μm otology CT]

Objective: To evaluate the morphology of isthmus of the vestibular aqueduct (VA) and its relationship with the occurrence, course of Meniere's disease (MD) and the degree of hearing loss based on 10 μm otology CT. Methods: A total of 13 patients with MD in Beijing Friendship Hospital, Capital Medical University from October 2020 to July 2021, including 4 males and 9 females, age from 16 to 77 (56±16) years, were prospectively enrolled. All patients underwent 10 μm otology CT examination. The included lesion side was the MD affected group (14 sides), and the non-lesion side was the MD healthy group (12 sides). According to the 1∶2 side, 16 sex-and side matched cases (28 sides) without external and middle ear disease were included in the control group, including 4 males and 12 females, age from 16 to 77 (56±14) years. The horizontal semicircular canal showed on the largest plane was considered as the standard cross-section, and continuous observation was made on this image. According to the display type of isthmus of the VA, it was divided into Ⅰ to Ⅳ grades. Kruskal Wallis test was used to compare the morphological differences of VA isthmus among the affected group, the healthy group and the control group. The degree of hearing impairment was assessed by pure tone audiometry (PTA) results, which were divided into normal/mild/moderate/moderately severe/severe/extremely severe hearing impairment. Spearman correlation analysis was used to compare the correlation between the morphological rating of VA isthmus on the affected side and age, course of disease and the results of pure tone audiometry (PTA). Results: The proportions of VA isthmic morphology GRADE Ⅰ,Ⅱ,Ⅲ,Ⅳ in the MD affected group were 28.6% (4/14), 42.9% (6/14), 21.4% (3/14), 7.1% (1/14), those in the MD healthy group were 0 (0/12), 33.3% (4/12), 33.3% (4/12), 33.3% (4/12), and those in the control group were 0 (0/28), 7.1% (2/28), 64.2% (18/28), 28.6% (8/28). The VA isthmus scores [M (Q1, Q3)] of MD affected group was lower than that of MD healthy group [2 (1, 3) vs 3 (2, 4)] and control group [2 (1, 3) vs 3 (3, 4)] (all P<0.05, respectively). The morphology of the VA isthmus on the affected side of MD was negatively correlated with age (r=-0.81, P=0.002), and there was no correlation with the course of disease and degree of hearing impairment (r=-0.40, r=-0.26; all P>0.05, respectively). Conclusion: The stenosis of the VA isthmus in MD was a possible anatomical factor for the occurrence of MD.

[Analysis of the performance of a multi-view fusion and active contour constraint based deep learning algorithm for ossicles segmentation on 10 μm otology CT]

Objective: To explore the performance of a deep learning algorithm that combined multi-view fusion with active contour constrained for ossicles segmentation on the 10 μm otology CT images. Methods: The 10 μm otology CT image data from 79 cases (56 cases were from volunteers and 23 cases were from specimens) were retrospectively collected in the Radiology Department of Beijing Friendship Hospital from October 2019 to December 2020. An annotation of malleus, incus, and stapes were conducted. Then the datasets were established and were divided into training set (n=55), validation set (n=8), and test set (n=16). Using the rapid localization of the region of interest combined with the precise segmentation algorithm, the malleus, incus and stapes were segmented and fused from three perspectives of coronal, sagittal and cross-sectional views. Besides, an active contour loss was designed simultaneously for the segmentation of stapes. Dice similarity coefficient (DSC) was used as the objective evaluation metric for the evaluation of the segmentation results. The inter group DSC of the proposed method was compared with that of the basic method and other methods. Results: The average DSC values of the multi-view fusion segmentation algorithm for malleus, incus and stapes reached up to 94.2%±2.7%, 94.6%±2.6% and 76.0%±5.5%, respectively. After adopting the constraint of active contour loss method, the average DSC of stapes was improved (76.4%±5.4% vs 76.0%±5.5%). The visualization results also demonstrated that the segmentation results of the stapes were more complete. Conclusions: Multi-view fusion algorithm based on 10 μm otology CT images can realize accurate segmentation of malleus and incus. Combined with the constraint of active contour loss method, the segmentation accuracy of stapes can be further improved.

[Correlative factors of sigmoid sinus diverticulum formation in individuals without pulsatile tinnitus based on CT angiography]

Objective: To analyze the correlative factors of sigmoid sinus diverticulum(SSD) formation in individuals without pulsatile tinnitus based on computed tomography angiography (CTA). Methods: A hospital-based 1∶2 matched case-control study was performed on 42 cases with unilateral SSD and 84 controls for age, gender, and side-matched in Beijing Friendship Hospital affiliated to the Capital Medical University from January 2018 to December 2018.The signs including sigmoid sinus wall dehiscence, venous outflow dominance, transverse sinus stenosis, high jugular bulb, large emissary veins, degree of mastoid pneumatization (grade Ⅰ-Ⅳ) and empty sella, were detected and analyzed. Results: In SSD group and control group, there were statistically significant differences in the incidence of the sigmoid sinus wall dehiscence (66.7%(28/42) vs 19.0%(16/84)), ipsilateral transverse sinus stenosis on the dominant side of venous outflow (26.2%(11/42) vs 4.8%(4/84)), and empty sellae (19.0%(8/42) vs 7.1%(6/84))(all P<0.05).The degree of mastoid pneumatization was worse in SSD group (P<0.05). After stepwise logistic regression analysis,the sigmoid sinus wall dehiscence (P<0.01,OR=6.794,95%CI 2.530-18.245), ipsilateral transverse sinus stenosis on the dominant side (P=0.001, OR=13.293, 95%CI 2.841-62.194), and degree of mastoid pneumatization (P<0.01, OR=0.289, 95%CI 0.156-0.536) were found independently correlated with SSD. Conclusion: Sigmoid sinus wall dehiscence, ipsilateral transverse sinus stenosis on the dominant side of venous outflow and mastoid pneumatization may be some of the independent correlative factors of SSD.

Overexpression of BLM promotes DNA damage and increased sensitivity to platinum salts in triple-negative breast and serous ovarian cancers

Background

Platinum-based therapy is an effective treatment for a subset of triple-negative breast cancer and ovarian cancer patients. In order to increase response rate and decrease unnecessary use, robust biomarkers that predict response to therapy are needed.

Patients and methods

We performed an integrated genomic approach combining differential analysis of gene expression and DNA copy number in sensitive compared with resistant triple-negative breast cancers in two independent neoadjuvant cisplatin-treated cohorts. Functional relevance of significant hits was investigated in vitro by overexpression, knockdown and targeted inhibitor treatment.

Results

We identified two genes, the Bloom helicase (BLM) and Fanconi anemia complementation group I (FANCI), that have both increased DNA copy number and gene expression in the platinum-sensitive cases. Increased level of expression of these two genes was also associated with platinum but not with taxane response in ovarian cancer. As a functional validation, we found that overexpression of BLM promotes DNA damage and induces sensitivity to cisplatin but has no effect on paclitaxel sensitivity.

Conclusions

A biomarker based on the expression levels of the BLM and FANCI genes is a potential predictor of platinum sensitivity in triple-negative breast cancer and ovarian cancer.

The CHK1 Inhibitor Prexasertib Exhibits Monotherapy Activity in High-Grade Serous Ovarian Cancer Models and Sensitizes to PARP Inhibition

PURPOSE

PARP inhibitors are approved for the treatment of high-grade serous ovarian cancers (HGSOC). Therapeutic resistance, resulting from restoration of homologous recombination (HR) repair or replication fork stabilization, is a pressing clinical problem. We assessed the activity of prexasertib, a checkpoint kinase 1 (CHK1) inhibitor known to cause replication catastrophe, as monotherapy and in combination with the PARP inhibitor olaparib in preclinical models of HGSOC, including those with acquired PARP inhibitor resistance.

EXPERIMENTAL DESIGN

Prexasertib was tested as a single agent or in combination with olaparib in 14 clinically annotated and molecularly characterized luciferized HGSOC patient-derived xenograft (PDX) models and in a panel of ovarian cancer cell lines. The ability of prexasertib to impair HR repair and replication fork stability was also assessed.

RESULTS

Prexasertib monotherapy demonstrated antitumor activity across the 14 PDX models. Thirteen models were resistant to olaparib monotherapy, including 4 carrying BRCA1 mutation. The combination of olaparib with prexasertib was synergistic and produced significant tumor growth inhibition in an olaparib-resistant model and further augmented the degree and durability of response in the olaparib-sensitive model. HGSOC cell lines, including those with acquired PARP inhibitor resistance, were also sensitive to prexasertib, associated with induction of DNA damage and replication stress. Prexasertib also sensitized these cell lines to PARP inhibition and compromised both HR repair and replication fork stability.

CONCLUSIONS

Prexasertib exhibits monotherapy activity in PARP inhibitor-resistant HGSOC PDX and cell line models, reverses restored HR and replication fork stability, and synergizes with PARP inhibition.

[Value of gadoxetate disodium-enhanced magnetic resonance on hepatobiliary phase T1 mapping for predicting liver injury]

Objective: To evaluate the measured value of gadoxetic disodium - enhanced T1-weighted magnetic resonance for the prediction of liver damage (LD) including liver fibrosis and inflammation. Methods: Retrospectively analyzed laboratory data of 115 patients with pathological results including prothrombin time (PT), albumin, serum total bilirubin level (TBil), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and magnetic resonance measurements (T1 measurement before and after enhancement and hepatobiliary specific phase T1pre, T1post, and changes in T1 relaxation time before and after enhancement were measured). The correlation between LD and magnetic resonance measurements was assessed by Spearman's correlation. All cases were divided into two groups: LD < 1 and LD≥1 (n1 = 26, n2 = 89), and the mean value of both groups was compared by t-test or Mann-Whitney U test. The independent influence factors of LD were obtained by binary logistic regression model. The area under receiver operating characteristics (AUROC) curve was performed on T1pre, T1post, and variation values. Results: Spearman's correlation test showed that T1post and variation values ​​were significantly associated with LD, and the correlation coefficients were 0.435, -0.353 and P < 0.05, respectively. The mean values ​​of T1post, variation values, PT, albumin, ALT and AST were statistically significant (P < 0.05). Binary logistic regression model showed T1post (P = 0.006), PT (P = 0.003), and AST (P = 0.032) were independent influencing factors of LD. T1- post contrast was good predictor of liver damage (AUC = 0.800). Conclusion: T1-post contrast predicts the existence of liver damage and provides useful information for clinical diagnosis and treatment.

[Comparative study on the display ability of CBCT and MSCT in vestibular aqueduct]

Objective: To compare the ability and visibility of cone-beam CT and MSCT in showing vestibular aqueduct. Methods: An experimental anatomical study which from June 2017 to August 2017 was performed on 76 temporal bones from 38 human cadavers with unknown clinical history. They all underwent CBCT and MSCT and all images were unified and standardized. The standard position was oblique sagital reconstruction.The length of the vestibular aqueduct, the midpoint and the external aperture width were measured on the standard position. The internal aperture, isthmus and proximal portion of the vestibular aqueduct on the images of the two kinds of equipment were evaluated. The measurement results of the two devices and image quality of the vestibular aqueduct were compared. Results: There was no significant statistical difference between the results of the measurement of CBCT and MSCT(P>0.05). In CBCT images, the total display rate of internal aperture was 77.6%(59/76), and the clearly display rate was 81.4%(48/59). The total display rate of the proximal portion of vestibular aqueduct was 57.0%(45/79), and the clearly display rate was 60.0%(27/45). The total display rate of isthmus of vestibular aqueduct was 59.2%(45/76), and the clearly display rate was 60.0%(27/45). In MSCT images, the total display rate of was 46.1%(35/76), and the clearly display rate was 60.0%(21/35). The total display rate of 5 of the proximal portion of vestibular aqueduct was 56.6%(43/76), the clearly display rate was 46.5%(20/43). The total display rate of isthmus of vestibular aqueduct was 68.4%(52/76), and the clear display rate 36.5%(19/52). There was significant statistical difference between the CBCT and the MSCT (P<0.05) in displaying of internal aperture of vestibular aqueduct. Conclusion: Compared with MSCT, the image of vestibular aqueduct obtained by CBCT can meet the diagnostic requirements and CBCT have better visibility in showing some subtle structures of vestibular aqueduct than MSCT.

[Inflammatory priming adipose derived stem cells significantly inhibit the proliferation of peripheral blood mononuclear cells]

OBJECTIVE

To explored whether adipose derived stem cells (ASCs) could inhibit the pro-liferation of peripheral blood mononuclear cells (PBMCs) and whether inflammatory priming could enhance this property of ASCs.

METHODS

We isolated ASCs using collagenase from adipose tissue and expanded them in vitro. Cells were induced to differentiate into adipogenic and osteogenic lineages. The cells at passage 3 to passage 5 were used for the experiments. After carboxy fluoresce in succinimidyl ester (CFSE) staining, PBMCs were co-cultured with inflammatory priming ASCs. The PBMCs cultured without ASCs or with non-treated ASCs defined as control groups. Then we used flow cytometry to detect the proliferation of PBMCs.

RESULTS

ASCs had fibroblast-like phenotype and were spindle shaped. They were able to differentiate into cells of adipogenic and osteogenic lineages in specific induction media. ASCs had the CD expression profile consistant with the International Federation for Adipose Therapeutics statement. The percentage of parent cells in PBMC after co-cultured with ASCs increased, though there was no statistical significance. However, when co-cultured with inflammatory priming ASCs, the percentage of parent cells significantly increased (with inflammatory priming ASCs group vs. without ASCs group, 38.7%±10.0% vs. 28.4%±8.9%, P<0.05). This indicated that inflammatory priming ASCs could significantly inhibit the proliferation of PBMCs.

CONCLUSION

Inflammatory cytokines can enhance the immunosuppressive ability of ASCs. Our findings may help the application of ASCs in tissue repairment with better results.

[Feasibility study of cone-beam CT in displaying facial nerve canal]

Objective: To evaluate the image clarity of cone-beam computed tomography (CBCT) in displaying facial nerve canal and to investigate the feasibility of CBCT to display facial nerve canal and whether there are some advantages compared with MSCT. Methods: Eight cadaveric heads were scanned using CBCT and MSCT and images of 16 temporal bones of each scanner were obtained.The imaging clarity of facial nerve canal of the two scanners was scored.Wilcoxon test was used to assess the difference of the two methods.P<0.05 was considered statistically significant. The defects of the wall of facial nerve canal were also observed in the images of both scanners. Results: Sixteen structures of facial nerve canal were evaluated, including the wall of labyrinthine segment, the anterior, medial, lateral, superior, inferior wall of the first genu, the lateral, inferior wall of the anterior part of tympanic segment, the lateral, inferior wall of the posterior part of tympanic segment, the medial and superior wall of tympanic segment, the lateral, inferior, superior, medial wall of the second genu and the wall of mastoid segment.The clarity of thirteen structures showed no differences between the two scanners (P>0.05). The clarity of three structures showed significant differences between CBCT and MSCT (P<0.05), which included the superior wall of the first genu, the posterior part of the lateral wall and the anterior part of the inferior wall of tympanic segment, and the scores of CBCT were higher than MSCT.The most frequent region of defect was in the anterior part of inferior wall of tympanic segment (14/16), followed by the inferior wall of labyrinthine segment (9/16) and the superior wall of tympanic segment (6/16). Conclusion: Compared with MSCT, CBCT could also gain quite good imaging clarity for displaying facial nerve canal. The display effect of some fine structures, such as the lateral wall of tympanic segment, is better in the images of CBCT than in those of MSCT.

Effects of sources and concentrations of zinc on growth performance, nutrient digestibility, and fur quality of growing-furring female mink (Mustela vison)

A completely randomized 3 × 3 + 1 factorial experiment was conducted to evaluate the effects of sources and concentrations of Zn on growth performance, nutrient digestibility, serum biochemical endpoints, and fur quality in growing-furring female black mink. One hundred fifty healthy 15-wk-old female mink were randomly allocated to 10 dietary treatments ( = 15/group) for a 60-d trial. Animals in the control group were fed a basal diet, which consisted of mainly corn, soybean oil, meat and bone meal, and fish meal, with no Zn supplementation. Mink in the other 9 treatments were fed the basal diet supplemented with Zn from either zinc sulfate (ZnSO), zinc glycinate (ZnGly), or Zn pectin oligosaccharides (ZnPOS) at concentrations of either 100, 300, or 900 mg Zn/kg DM. The results showed that mink in the ZnPOS groups had higher ADG than those in the ZnSO groups (main effect, < 0.05). The addition of Zn reduced the G:F ( < 0.05). In addition, CP and crude fat digestibility were linearly increased with Zn supplementation ( < 0.05) and N retention tended to increase with Zn addition ( = 0.08). Dietary Zn supplementation increased the concentration of serum albumin and activity of alkaline phosphatase ( < 0.05). There was a linear effect of dietary Zn on the concentration of tibia Zn and pancreatic Zn ( < 0.05). For fur quality characteristics, the fur density and hair color of mink were improved by dietary Zn concentration ( < 0.05). Compared with ZnSO (100%), relative bioavailability values of ZnGly were 115 and 118%, based on tibia and pancreatic Zn, respectively, and relative bioavailability values of ZnPOS were 152 and 142%, respectively. In conclusion, this study demonstrates that Zn supplementation can promote growth and increase nutrient digestibility and fur quality and that ZnPOS is more bioavailable than ZnSO and ZnGly in growing-furring female mink.

Tunneling anisotropic magnetoresistance driven by magnetic phase transition

The independent control of two magnetic electrodes and spin-coherent transport in magnetic tunnel junctions are strictly required for tunneling magnetoresistance, while junctions with only one ferromagnetic electrode exhibit tunneling anisotropic magnetoresistance dependent on the anisotropic density of states with no room temperature performance so far. Here, we report an alternative approach to obtaining tunneling anisotropic magnetoresistance in α′-FeRh-based junctions driven by the magnetic phase transition of α′-FeRh and resultantly large variation of the density of states in the vicinity of MgO tunneling barrier, referred to as phase transition tunneling anisotropic magnetoresistance. The junctions with only one α′-FeRh magnetic electrode show a magnetoresistance ratio up to 20% at room temperature. Both the polarity and magnitude of the phase transition tunneling anisotropic magnetoresistance can be modulated by interfacial engineering at the α′-FeRh/MgO interface. Besides the fundamental significance, our finding might add a different dimension to magnetic random access memory and antiferromagnet spintronics.

Tunneling anisotropic magnetoresistance is promising for next generation memory devices but limited by the low efficiency and functioning temperature. Here the authors achieved 20% tunneling anisotropic magnetoresistance at room temperature in magnetic tunnel junctions with one α′-FeRh magnetic electrode.

Abstract NTOC-112: GENOMIC SCARS AND CLINICAL RESPONSE TO COMBINATION THERAPY OF PARP AND ANGIOGENESIS INHIBITORS IN OVARIAN CANCER

BACKGROUND: Genomic instability, frequently resulting in chromosomal allelic deletion with allelic imbalance (AI)/loss of heterozygosity (LOH), is characteristic of high-grade serous ovarian cancer (HGSOC). Frequent allelic deletion is thought to arise from deficiency in DNA repair by homologous recombination (HR) resulting in the so called “genomic scars” of HR deficiency. Quantification of AI/LOH events in the tumor genome has previously been shown to predict response to therapy using platinum compounds. Recently, PARP inhibitors have proved useful in treating a sub-set of patients with HGSOC, particularly tumors harboring BRCA1/2 mutations. Combination with an angiogenesis inhibitor significantly improved the outcome. This study explores the potential of using AI/LOH scores to predict clinical response of HGSOC to PARP inhibition alone or in combination with an angiogenesis inhibitor.

MATERIALS AND METHODS: Molecular inversion probe array data were generated using tumors from a sub-set of patients (n=37) enrolled in a clinical trial comparing the PARP inhibitor Olaparib to the combination of Olaparib with the anti-angiogenic agent Cediranib (NCT01116648). AI/LOH regions were identified using an ASCAT based algorithm. Markers of genomic instability associated with DNA repair deficiency were scored. These quantify AI regions (NAI), telomeric AI (NtAI), large scale transition (LST), fraction of LOH (FLOH), and HRD-LOH. dChip was used for copy number analysis. The best overall response to therapy was determined using the RECIST 1.1 criteria for complete and partial response (CR, n = 3 and PR, n = 18), and stable disease without objective response (SD, n = 16).

RESULTS: A high tumor NAI-score was positively correlated with the degree of clinical response to therapy (either olaparib alone or in combination with cediranib) (Chi-square test for trend, p = 0.036). This association remains statistically significant in the subgroup carrying BRCA mutations (n = 22, Chi-square test for trend, p = 0.0488). In this limited sample, the objective response rate of high NAI tumors to the combination therapy was high (7 out of 8), especially in patient carrying wild-type BRCA1/2 genes (2 out of 2, p = 0.045). The results suggest NAI may be a potential genomic marker for response to the therapy combining PARP and angiogenesis inhibitors. However, no significant association was observed between the degree of objective response and scores of other genomic measurements NtAI, LST, or HRD-LOH.

SUMMARY: High NAI-score was associated with objective response to olaparib, alone or in combination with cediranib, supporting NAI as a candidate of genomic marker for predicting response to PARP inhibitor-based therapy in HGSOC. A larger cohort would be required to further evaluate predictive value of NAI for response to the combinational therapy.

Citation Format: Zhigang C. Wang, Nicolai Juul Birkbak, William T. Barry, Thomas M. Roberts, Eric P. Winer, J Dirk Iglehart, Ursula A. Matulonis, S. Percy Ivy, and Joyce F. Liu. GENOMIC SCARS AND CLINICAL RESPONSE TO COMBINATION THERAPY OF PARP AND ANGIOGENESIS INHIBITORS IN OVARIAN CANCER [abstract]. In: Proceedings of the 11th Biennial Ovarian Cancer Research Symposium; Sep 12-13, 2016; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(11 Suppl):Abstract nr NTOC-112.

Effects of dynamic diffraction conditions on magnetic parameter determination in a double perovskite Sr2FeMoO6 using electron energy-loss magnetic chiral dichroism

Electron energy-loss magnetic chiral dichroism (EMCD) spectroscopy, which is similar to the well-established X-ray magnetic circular dichroism spectroscopy (XMCD), can determine the quantitative magnetic parameters of materials with high spatial resolution. One of the major obstacles in quantitative analysis using the EMCD technique is the relatively poor signal-to-noise ratio (SNR), compared to XMCD. Here, in the example of a double perovskite Sr₂FeMoO₆, we predicted the optimal dynamical diffraction conditions such as sample thickness, crystallographic orientation and detection aperture position by theoretical simulations. By using the optimized conditions, we showed that the SNR of experimental EMCD spectra can be significantly improved and the error of quantitative magnetic parameter determined by EMCD technique can be remarkably lowered. Our results demonstrate that, with enhanced SNR, the EMCD technique can be a unique tool to understand the structure-property relationship of magnetic materials particularly in the high-density magnetic recording and spintronic devices by quantitatively determining magnetic structure and properties at the nanometer scale.

[Study on correlation between retinal vessel morphology or ocular hemodynamic parameter and internal carotid artery stenosis]

Objective: To analyze the correlation between retinal vascular calibers, ocular blood flow parameters and internal carotid artery stenosis and to evaluate the effect of internal carotid artery stenosis on ocular blood vessels comprehensively. Methods: A retrospective case-control study. The clinical data of 141 patients who underwent head-and-neck computed tomography (CT) angiography examinations of the ICA were collected at Beijing Friendship Hospital, Capital Medical University from January 2014 to January 2016. According to diagnostic criteria, the patients were divided into four groups: the non-stenosis group, the mild stenosis group, the moderate stenosis group, and the severe stenosis andocclusion group. The retinal vascular caliber was measured in color fundus photograph by IVAN software. Color Doppler ultrasonography was used to measure the parameters of ocular blood flow, including the peak systolic velocity (PSV), end diastolic velocity (EDV), resistance index (RI) and pulsatility index (PI). The enumeration data were analyzed with chi-square test, the measurement data were analyzed with rank-sum test, and the correlation test was performed with spearman. Results: The gender ratio of the patients without stenosis, mild stenosis, moderate stenosis, severe stenosis and occlusion was 12/7, 31/19, 28/25, 12/7, χ² test was not statistically significant (χ²= 0.79, P=0.85); There was no statistically significant difference between the different groups (χ²= 0.15, P=0.68), the age of four groups were (64.1±8.3), (54.3±14.3), (68.9±11.8) and (59.1±8.0) y, respectively. In the no internal carotid artery stenosis group, the arteries diameter is (164.5±15.6) μm ,the vein diameter is (245.6±20.0) μm and the arteriovenous ratio is 0.7±0.1. There is no difference among the mild stenosis group, moderate stenosis group and the severe stenosis (χ²_{artery calibe}r=6.92, P_{artery calibe}r=0.08; χ²_{vein diamete}r=4.16, P_{vein diamete}r=0.25; χ²_{arteriolar-venular ratio}=1.38,P_{arteriolar-venular ratio}=0.71) . The PSV of central retinal artery in the above groups were (14.6±3.6), (34.4±13.2), (35.7±14.6), (42.3±19.0)cm/s respectively, the data were analyzed by rank-sum test and there was a significant difference (χ²=13.44, P< 0.01) ; The PSV of the posterior ciliary artery in the above groups (17.6±6.5), (15.0±4.6), (13.4±4.3) and (11.0±3.2)cm/s respectively, the data were analyzed by rank-sum test and there was a significant difference (χ²=22.71, P<0.01) , EDV were (5.90±2.2), (5.1±2.1), (4.3±1.5) and (4.3±4.8)cm/s respectively and there was a significant difference (χ²=20.36, P<0.01) .There was a correlation between retinal artery diameter, PSV and EDV of the central retinal artery, PSV and EDV of the posterior ciliary artery and the diameter of the internal carotid artery but without linear correlation. (r_{artery calibe}r=-0.23, P_{artery calibe}r=0.01; r_{PSV of central retinal artery}= -0.29, P_{PSV of central retinal artery}<0.01; r_{PSV of posteri or ciliary artery}=-0.34, P_{PSV of posterior ciliary artery}<0.01, r_{EDV of posterior ciliary artery}=-0.35, P_{EDV of posterior ciliary artery}<0.01). Conclusions: There was a correlation between retinal artery diameter, PSV and EDV of the central retinal artery, PSV and EDV of the posterior ciliary artery and the diameter of the internal carotid artery. PSV of the central retinal artery, PSV and EDV of the posterior ciliary artery changed significantly when the internal carotid artery stenosis existed. (Chin J Ophthalmol, 2016, 52: 905-910).

Enhanced immunity and antiviral effects of an HBV DNA vaccine delivered by a DC-targeting protein

DNA vaccine targeting delivery to DC represents one effective strategy to improve the immunogenicity of the vaccine. In a previous study, we developed a novel DC-targeting recombinant protein that can deliver plasmid DNA to DCs by an electrostatic coupling effect and can thus improve the uptake efficiency of DCs, improving the expression of plasmid DNA in DCs. In this study, we coupled the protein with the HBV DNA vaccine pSVK-HBVA and investigated whether the immunogenicity and antiviral ability of the vaccine can be improved in HBV transgenic mice. The results show that a stronger specific immune response can be induced in mice after immunization with the coupling vaccine. The HBV DNA copy number and circulating antigen HBsAg in the serum of HBV transgenic mice were significantly decreased. Therefore, this study has demonstrated that the DC-targeting protein has the ability to improve the immunogenicity and the antiviral activity of the HBV DNA vaccine pSVK-HBVA. These findings indicate that this DC-targeting protein can be a potential method for the delivery of DNA vaccines directly to DCs.

Combination inhibition of PI3K and mTORC1 yields durable remissions in mice bearing orthotopic patient-derived xenografts of HER2-positive breast cancer brain metastases

Brain metastases represent the greatest clinical challenge in treating HER2-positive breast cancer. We report the development of orthotopic patient-derived xenografts (PDXs) of HER2-expressing breast cancer brain metastases (BCBM), and their use for the identification of targeted combination therapies. Combined inhibition of PI3K and mTOR resulted in durable tumor regressions in three of five PDXs, and therapeutic response was correlated with a reduction in the phosphorylation of 4EBP1, an mTORC1 effector. The two nonresponding PDXs showed hypermutated genomes with enrichment of mutations in DNA-repair genes, which suggests an association of genomic instability with therapeutic resistance. These findings suggest that a biomarker-driven clinical trial of PI3K inhibitor in combination with an mTOR inhibitor should be conducted for patients with HER2-positive BCBM.

Characterization and identification of streptococci from golden pompano in China

Streptococcal infections cause significant mortality and high economic losses in the fish farm industry worldwide, including in the culture of golden pompano Trachinotus ovatus L., a species gaining popularity in China. A total of 9 streptococcal strains were isolated from cage-cultured diseased golden pompano in Beihai, Zhanjing, and Shenzhen, China, between 2012 and 2014. Conventional and rapid identification systems were used to determine that the isolates were Streptococcus agalactiae, S. iniae, and S. dysgalactiae subsp. dysgalactiae. All isolates were gram-positive cocci cells in pairs or short-chain, non-motile, catalase negative, α or β hemolytic cocci. The results of multiplex PCR assays and 16S rRNA BLAST analysis also showed that the β hemolytic strains were S. agalactiae and S. iniae and the α hemolytic strain was S. dysgalactiae subsp. dysgalactiae, respectively. Pathogenicity assays revealed that S. agalactiae (lethal dose [LD50]: 6.38 × 10(4) CFU ml(-1)) was more virulent for golden pompano than S. iniae (LD50: 1.47 × 10(7) CFU ml(-1)) and S. dysgalactiae subsp. dysgalactiae (LD50: 2.57 × 10(6) CFU ml(-1)) when they were challenged by intraperiotoneal (i.p.) injection. The results of antibiotic susceptibility showed that all strains were extremely susceptible to cefradine, erythromycin, and cefotaxime but resistant to gentamicin, penicillin G, novobiocin, neomycin, ciprofloxacin, roxithromycin, furazolidone, enrofloxacin, norfloxacin, kanamycin, ampicillin, tetracycline, and vancomycin This is the first report of a phenomenon of golden pompano coinfection with S. agalactiae and S. iniae, which will contribute to the diagnosis and prevention of streptococcicosis.

Temporal and spatial expression profiles of Frizzled 3 in the ovary during the estrous cycle

Frizzled 3 is an important receptor in the Wnt/β-catenin pathway, a conserved signaling pathway that regulates gene expression and controls diverse developmental processes. However, the role of this protein during follicular development in the adult ovary is not known. The present study was designed to investigate the expression and localization of Frizzled 3 mRNA and protein during the estrous cycle in the mouse ovary through in situ hybridization (ISH), real-time quantitative polymerase chain reaction, immunohistochemistry and western blot. ISH results showed that in proestrus, high expression of Frizzled 3 was found in the granulosa and stroma with weak levels in the corpus luteum. In estrus and diestrus, the stroma had high Frizzled 3 expression, but levels were low in granulosa cells and corpus luteum. In the metestrus, moderate expression of Frizzled 3 was found in the stroma but low to no expression was found in luteal cells and follicles. The mRNA and protein levels of Frizzled 3 were found to be the highest in proestrus and diestrus compared to estrus and metestrus (P < 0.05), confirming the ISH results. During estrus and diestrus, high Frizzled 3 expression was observed in the stroma and moderate levels in granulosa cells, and during estrus and proestrus, low expression was seen in the oocyte cell membrane. The western blot results further confirmed this change during the estrous cycle. Together, these results indicate that Frizzled 3 is involved in regulating follicular development and oocyte maturation during the estrous cycle.

CDK7-dependent transcriptional addiction in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer that exhibits extremely high levels of genetic complexity and yet a relatively uniform transcriptional program. We postulate that TNBC might be highly dependent on uninterrupted transcription of a key set of genes within this gene expression program and might therefore be exceptionally sensitive to inhibitors of transcription. Utilizing kinase inhibitors and CRISPR/Cas9-mediated gene editing, we show here that triple-negative but not hormone receptor-positive breast cancer cells are exceptionally dependent on CDK7, a transcriptional cyclin-dependent kinase. TNBC cells are unique in their dependence on this transcriptional CDK and suffer apoptotic cell death upon CDK7 inhibition. An "Achilles cluster" of TNBC-specific genes is especially sensitive to CDK7 inhibition and frequently associated with super-enhancers. We conclude that CDK7 mediates transcriptional addiction to a vital cluster of genes in TNBC and CDK7 inhibition may be a useful therapy for this challenging cancer.

Effects of HIF prolyl-hydroxylase-2 gene silencing on HCG-induced vascular endothelial growth factor expression in luteal cells

Vascular endothelial growth factor (VEGF)-dependent angiogenesis plays a crucial role in corpus luteum formation and its functional maintenance in mammalian ovaries. We recently reported that activation of hypoxia-inducible factor (HIF)-1α signaling contributes to the regulation of VEGF expression in luteal cells (LCs) in response to human chorionic gonadotropin (HCG). We examined whether HIF prolyl-hydroxylase (PHD)-2 gene silencing induces VEGF expression in LCs and enhanced its expression induced by HCG in LCs. Using real-time polymerase chain reaction and western blot analysis, we measured the expression of PHD-2 to confirm plasmid PHD-2 shRNA transfection and protein expression and investigated the changes in HIF-1a and VEGF expression after treatment with HCG and PHD-2 shRNA transfection. After PHD-2 shRNA transfection, PHD-2 expression was significantly lower than that in control groups with or without HCG treatment, while a significant increase in VEGF mRNA was observed compared to in controls, indicating that PHD-2 plays an important role in VEGF regulation. Additionally, changes in VEGF mRNA expression were consistent with the expression levels of HIF-1a protein, not HIF- 1a mRNA, which is regulated by HIF prolyl-hydroxylase-mediated degradation. Our results indicate that PHD-2 gene silencing can induce VEGF expression in LCs and HCG-induced VEGF expression can be further enhanced by PHD-2 gene silencing through an HIF-1a-mediated mechanism in LCs. This PHD-2-mediated transcriptional activation may be important for regulating VEGF expression through HIF-1a signaling in LCs during corpus luteum development in mammals.

RelA-Induced Interferon Response Negatively Regulates Proliferation

Both oncogenic and tumor-suppressor activities are attributed to the Nuclear Factor kappa B (NF-kB) pathway. Moreover, NF-kB may positively or negatively regulate proliferation. The molecular determinants of these opposing roles of NF-kB are unclear. Using primary human mammary epithelial cells (HMEC) as a model, we show that increased RelA levels and consequent increase in basal transcriptional activity of RelA induces IRF1, a target gene. Induced IRF1 upregulates STAT1 and IRF7, and in consort, these factors induce the expression of interferon response genes. Activation of the interferon pathway down-regulates CDK4 and up-regulates p27 resulting in Rb hypo-phosphorylation and cell cycle arrest. Stimulation of HMEC with IFN-γ elicits similar phenotypic and molecular changes suggesting that basal activity of RelA and IFN-γ converge on IRF1 to regulate proliferation. The anti-proliferative RelA-IRF1-CDK4 signaling axis is retained in ER+/HER2- breast tumors analyzed by The Cancer Genome Atlas (TCGA). Using immuno-histochemical analysis of breast tumors, we confirm the negative correlation between RelA levels and proliferation rate in ER+/HER2- breast tumors. These findings attribute an anti-proliferative tumor-suppressor role to basal RelA activity. Inactivation of Rb, down-regulation of RelA or IRF1, or upregulation of CDK4 or IRF2 rescues the RelA-IRF1-CDK4 induced proliferation arrest in HMEC and are points of disruption in aggressive tumors. Activity of the RelA-IRF1-CDK4 axis may explain favorable response to CDK4/6 inhibition observed in patients with ER+ Rb competent tumors.

Effect of HIF-1a/VEGF signaling pathway on plasma progesterone and ovarian prostaglandin F₂a secretion during luteal development of pseudopregnant rats

The corpus luteum is a temporary endocrine structure in mammals that plays an important role in the female reproductive cycle and is formed from a ruptured and ovulated follicle with rapid angiogenesis. Vascular endothelial growth factor (VEGF) is thought to be vital in normal and abnormal angiogenesis in the ovary, but the molecular regulation of luteal VEGF expression during corpus luteum development in vivo is still poorly understood at present. Therefore, we examined whether hypoxia-inducible factor-1a (HIF-1a) is induced and regulates VEGF expression and luteal function in vivo using a pseudopregnant rat model treated with a small-molecule inhibitor of HIF-1a, echinomycin. Corpus luteum development in the pseudopregnant rat ovary was determined after measuring plasma progesterone concentration and ovarian prostaglandin F2a content to reflect changes in HIF-1a and VEGF on different days of this developmental process. At day 7, the corpus luteum was formed and the expression of HIF- 1a/VEGF reached a maximum, while a significant decrease in HIF-1a/ VEGF expression was observed when luteolysis occurred at day 13. Additionally, echinomycin blocked luteal development by inhibiting VEGF expression mediated by HIF-1a and following luteal function by detecting the progesterone changes at day 7. These results demonstrated that HIF-1a-mediated VEGF expression might be an important mechanism regulating ovarian luteal development in mammals in vivo, which may provide new strategies for fertility control and for treating some types of ovarian dysfunction, such as polycystic ovarian syndrome, ovarian hyperstimulation syndrome, and ovarian neoplasia.

Abstract P3-06-11: Homologous recombination deficiency (HRD) assay predicts response to cisplatin neoadjuvant chemotherapy in patients with triple negative breast cancer

A significant proportion of triple negative breast cancers (TNBC) carry defects in DNA repair including Homologous Recombination (HR) defects and are sensitive to therapies that target these pathways. Several clinical trials have demonstrated improvement in pathologic response with the addition of platinum to standard of care neoadjuvant regimens but at a cost of increased toxicities. Recently three DNA based metrics (LOH, Abkevich et al. 2012 Br J Cancer; TAI, Birkbak et al. 2012 Cancer Discov; LST, Popava et al. 2012 Cancer Res) have been developed, shown to be highly associated with BRCA1/2 mutation status, and found to predict sensitivity to platinum based chemotherapy in TNBC. The HRD Score was defined as the sum of LOH, TAI, and LST measurements, and a threshold separating tumors with high and low HRD Scores was established. This study assesses the association of HRD Score with response to cisplatin neoadjuvant chemotherapy in patients with TNBC. A clinical test that identifies tumors with defects in HR may distinguish those patients more likely to benefit from the addition of platinum.

Methods: Archival tumor samples were obtained from 74 patients with TNBC from 2 separate clinical trials conducted at DFHCC under IRB approved protocols. One trial enrolled 28 patients who received neoadjuvant cisplatin monotherapy (Silver et al., 2010 J Clin Oncol). The second trial enrolled 51 patients who received cisplatin and bevacizumab chemotherapy (Ryan, et al.,2009 J Clin Oncol). HRD Score and tumor BRCA1/2 mutation status were determined. BRCA1/2 deficiency was defined as the presence of BRCA1/2 mutation with loss of the second allele in the tumor. Response was categorized by the residual cancer burden (RCB) score with responders defined as RCB0 or 1, and non-responders as RBC2 or 3. A second measure of response, pathologic complete response (pCR), was defined as RCB0 and non-responders as RCB1,2 or 3. Logistic regression was used to evaluate HRD Score in combination with BRCA1/2 deficiency as a predictor of response to neoadjuvant therapy. All analysis was conducted according to a pre-specified Statistical Analysis Plan.

Results: As of May 29, 2014 41 samples have been processed. Seven carried deleterious mutations in BRCA1/2 (17%). Thirty-three of the tumors produced SNP data of sufficient quality for HRD score calculation. HRD scores in the passing samples ranged from 7 – 74, with an average score of 45. The HRD scores observed in BRCA1/2 mutation carriers (n=6) ranged from 43 – 57 with an average HRD score of 55. We anticipate that all molecular data will be generated by July 1, 2014. Correlation with pCR and RCB0/1 will be assessed.

Conclusions: The LOH, TAI, and LST metrics have been shown in previous studies to predict response to platinum-based neoadjuvant chemotherapy in patients with TNBC. This study will be a validation of LOH, TAI and LST in the form of a combined score, and will demonstrate that HRD Score can be used as a tool to identify patients with breast tumors with underlying HR deficiency who may benefit from platinum therapy.

Citation Format: Andrea L Richardson, Daniel P Silver, Zoltan Szallasi, Nicolai J Birkbak, Zhigang C Wang, J Dirk Iglehart, Erica L Mayer, Eric P Winer, Nadine M Tung, Paula D Ryan, Steven J Isakoff, William T Barry, April Greene-Collozi, Alexander Gutin, Julia Reid, Chris Neff, Joshua Jones, Kirsten Timms, Anne-Renee Hartman, Judy E Garber. Homologous recombination deficiency (HRD) assay predicts response to cisplatin neoadjuvant chemotherapy in patients with triple negative breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-11.

Pan-cancer analysis of genomic scar signatures associated with homologous recombination deficiency suggests novel indications for existing cancer drugs

BACKGROUND

Ovarian and triple-negative breast cancers with BRCA1 or BRCA2 loss are highly sensitive to treatment with PARP inhibitors and platinum-based cytotoxic agents and show an accumulation of genomic scars in the form of gross DNA copy number aberrations. Cancers without BRCA1 or BRCA2 loss but with accumulation of similar genomic scars also show increased sensitivity to platinum-based chemotherapy. Therefore, reliable biomarkers to identify DNA repair-deficient cancers prior to treatment may be useful for directing patients to platinum chemotherapy and possibly PARP inhibitors. Recently, three SNP array-based signatures of chromosomal instability were published that each quantitate a distinct type of genomic scar considered likely to be caused by improper DNA repair. They measure telomeric allelic imbalance (named NtAI), large scale transition (named LST), and loss of heterozygosity (named HRD-LOH), and it is suggested that these signatures may act as biomarkers for the state of DNA repair deficiency in a given cancer.

RESULTS

We explored the pan-cancer distribution of scores of the three signatures utilizing a panel of 5371 tumors representing 15 cancer types from The Cancer Genome Atlas, and found a good correlation between scores of the three signatures (Spearman's ρ 0.73-0.87). In addition we found that cancer types ordinarily receiving platinum as standard of care have higher median scores of all three signatures. Interestingly, we also found that smaller subpopulations of high-scoring tumors exist in most cancer types, including those for which platinum chemotherapy is not standard therapy.

CONCLUSIONS

Within several cancer types that are not ordinarily treated with platinum chemotherapy, we identified tumors with high levels of the three genomic biomarkers. These tumors represent identifiable subtypes of patients which may be strong candidates for clinical trials with PARP inhibitors or platinum-based chemotherapeutic regimens.

The effects of recombinant human epithelialgrowth factor and protein-free calf blood extract for recovery of corneal mechanical epithelial defects healing and neovascularization

OBJECTIVE

This study was undertaken to investigate the effects of recombinant human epidermal growth factor (rhEGF) and protein-free calf blood extract on corneal wound healing and neovascularization.

MATERIALS AND METHODS

An rabbit central corneal wound and neovascularization model was established in rabbits. One eye of each group was chosen randomly for topical administration of protein-free calf blood extract, rhEGF, or NS (physiological saline), and variability in the area of corneal epithelial wound healing and neovascularization was observed.

RESULTS

On days 1 and 2, the healing rate of corneal epithelium was various among the protein-free calf blood extract group, rhEGF group and NS group (F=6.475, p=0.012). The healing rate of corneal epithelium in the rhEGF group was better than the protein-free calf blood extract group (p=0.004) and NS group (p=0.041) on day 1. The corneal neovascularization area in the protein-free calf blood extract group was less than that of rhEGF group (p=0.04) and NS group (p=0.008) on day 18.

CONCLUSIONS

rhEGF had better promotive effect on corneal epithelial wound healing than the protein-free calf blood extract in the advanced phase (within 2 days). Both rhEGF and protein-free calf blood extract were not found to promote.

Abstract 2822: A pan-cancer analysis of inferred homologous recombination deficiency identifies potential platinum benefit in novel subtypes

Personalized medicine in cancer aims to improve treatment outcome, by exploiting the molecular alterations of the individual tumor to inform therapeutic decisions. Ovarian and triple-negative breast cancers with defects in homologous recombination (HR) DNA repair are highly sensitive to treatment with platinum-based DNA-damaging agents. Reliable biomarkers to identify HR-deficient cancers prior to the initial treatment may be used to stratify patients for platinum chemotherapy. Extensive genome damage caused by deficient HR is readily observed as high frequencies of allelic imbalance and loss of heterozygosity in cancers with loss of either of the tumor suppressor genes BRCA1 or BRCA2, but is also common in ovarian and triple-negative breast cancers with no BRCA1/2 mutations, indicating HR loss due to alternative mechanisms.

Recently, three independent methods were published that each quantitate the state of HR deficiency in a given cancer, by summarizing different types of DNA aberrations that are likely to be caused by improper DNA repair. Here we compare the three scores, named NtAI (1), LST (2), and HRD (3), utilizing a panel of 4400 patients representing 13 cancer types from The Cancer Genome Atlas.

We found that the three scores are highly correlated with each other, suggesting they measure the effect of similar types of DNA damage. We found a strong association with overall survival only in ovarian cancer, which is consistent with frequent BRCA-related HR deficiency reported for this type of cancer. Next, we compared the distribution of the scores across cancer types, and found that those types ordinarily receiving platinum as standard of care have the highest median scores. Importantly, in most types not generally given platinum chemotherapy we also found small sub-populations of high scoring tumors, which may represent subtypes with a previously overlooked potential to respond to platinum agents. Lastly, we used RNAseq to identify genes whose expression is associated with high DNA aberration scores. We compared the 100 genes most highly correlated with each score and found a shared set of 53 genes; these were enriched for genes involved in cell cycle progression, mitosis and chromosome segregation. This suggests that replication stress, perhaps combined with or induced by HR deficiency, could play a role in the generation of the measured DNA aberrations.

Overall, our results demonstrate that the three methods measure correlated aberration patterns possibly generated through replication stress, and that they show prognostic potential in patients who receive platinum chemotherapy. In addition, we identify subsets of patients suffering from cancers not presently receiving platinum chemotherapy, who may benefit from it.

1) Birkbak NJ, et al. (2012) Cancer Discov 2: 366-375

2) Popova T, et al. (2012) Cancer Res 72: 5454-5462

3) Abkevich V, et al. (2012) Br J Cancer 107: 1776-1782

Citation Format: Andrea M. Marquard, Aron C. Eklund, Zhigang C. Wang, Andrea L. Richardson, Zoltan Szallasi, Nicolai J. Birkbak. A pan-cancer analysis of inferred homologous recombination deficiency identifies potential platinum benefit in novel subtypes. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2822. doi:10.1158/1538-7445.AM2014-2822

Changes in cyclic GMP level and phosphodiesterase activity during follicular development in the rat ovary

Guanosine 3',5'-cyclic monophosphate (cGMP), as a second messenger, plays potential roles in ovarian functions. To elucidate the role of phosphodiesterase (PDE) in cGMP signaling during ovarian follicular development, the present study was conducted to investigate ovarian cGMP level and cGMP-PDE activity by radioimmunoassay (RIA) in postnatal rats, immature rats during gonadotropin-primed follicular development, ovulation and luteinization, adult rats during normal estrous cycle, and aged rats that spontaneously developed persistent estrus (PE). All four rat models were confirmed by histological examination of one ovary, and the other ovary was used for RIA. In postnatal rats, cGMP level was high at birth and decreased dramatically by Day 5, and then, it increased maximally at Day 10 and declined at Day 21. However, cGMP-PDE activity did not significantly change during Days 1 to 10, but increased significantly on Day 21. In immature female rats, cGMP level markedly decreased upon treatment with equine chorionic gonadotropin (eCG), while cGMP-PDE activity did not show any significant changes; however, ovarian cGMP level and cGMP-PDE activity increased after injection of an ovulatory dose of human chorionic gonadotropin (hCG) for induction of ovulation and luteinization. In adult rats during normal estrous cycle, cGMP level was high on proestrus and metestrus days, while cGMP-PDE activity was high on estrus day. In PE rats, ovarian cGMP level was similar to that in adult rats on estrus and diestrus days but lower than that on proestrus and metestrus days; ovarian cGMP-PDE activity was lower than that on estrus days but similar as the other estrous cycle days. In addition, there was a significant negative correlation between ovarian cGMP level and cGMP-PDE activity during normal estrous cycles in the adult rat (r = -0.7715, N = 16, P < 0.05), but not in the postnatal rat (r = -0.1055, N = 20, P > 0.05). Together, the results of our present study indicated that ovarian cGMP levels were not dependent on cGMP-PDE activity during early postnatal development, but highly dependent on cGMP-PDE activity in the adult rat. This implies that mechanisms of cGMP signaling involved in ovarian functions are stage-specific in the rat.

PRKACA mediates resistance to HER2-targeted therapy in breast cancer cells and restores anti-apoptotic signaling

Targeting HER2 with antibodies or small molecule inhibitors in HER2-positive breast cancer leads to improved survival, but resistance is a common clinical problem. To uncover novel mechanisms of resistance to anti-HER2 therapy in breast cancer, we performed a kinase open reading frame screen to identify genes that rescue HER2-amplified breast cancer cells from HER2 inhibition or suppression. In addition to multiple members of the MAPK (mitogen-activated protein kinase) and PI3K (phosphoinositide 3-kinase) signaling pathways, we discovered that expression of the survival kinases PRKACA and PIM1 rescued cells from anti-HER2 therapy. Furthermore, we observed elevated PRKACA expression in trastuzumab-resistant breast cancer samples, indicating that this pathway is activated in breast cancers that are clinically resistant to trastuzumab-containing therapy. We found that neither PRKACA nor PIM1 restored MAPK or PI3K activation after lapatinib or trastuzumab treatment, but rather inactivated the pro-apoptotic protein BAD, the BCl-2-associated death promoter, thereby permitting survival signaling through BCL-XL. Pharmacological blockade of BCL-XL/BCL-2 partially abrogated the rescue effects conferred by PRKACA and PIM1, and sensitized cells to lapatinib treatment. These observations suggest that combined targeting of HER2 and the BCL-XL/BCL-2 anti-apoptotic pathway may increase responses to anti-HER2 therapy in breast cancer and decrease the emergence of resistant disease.

Effect of gestational weight gain as well as rehabilitation training on postnatal pelvic muscle strength

OBJECTIVE

The current study explored the impact of gestational weight gain on postnatal pelvic muscle strength and the effect of low-frequency electrical stimulation combined with biofeedback training on strength recovery.

MATERIALS AND METHODS

A total of 126 mothers six to eight weeks after term delivery were recruited at Peking University Shenzhen Hospital from August 2010 to July 2011. According to gestational weight gain, they were divided into two groups: the < 15 kg (A) and > or = 15 kg (B) groups. Pelvic floor muscle fibre strength was determined. Target low-frequency electrical stimulation combined with biofeedback training was conducted. After training, pelvic floor muscle fiber strength was determined again for effect evaluation.

RESULTS

Before training, types I and II pelvic floor muscle fiber strength of group B was noticeably lower than that of group A (p < 0.05). After rehabilitation, the pelvic floor muscle strength of both groups significantly increased (p < 0.05). However, types I and II pelvic floor muscle fiber strength of group B was still significantly lower than that of group A (p < 0.05).

CONCLUSION

Gestational weight gain negatively influences pelvic floor muscles. Low-frequency electrical stimulation combined with biofeedback training improves postnatal pelvic floor muscle fiber strength. A less gestational weight increase indicates faster postnatal pelvic muscle strength recovery and a better rehabilitative effect.

Abstract P5-08-01: Systematic interrogation of resistance to HER2-directed therapy identifies a survival pathway activated by PRKACA and PIM1

Amplification and/or overexpression of the receptor tyrosine kinase HER2 occurs in 20-25% of breast cancers, and is associated with poor prognosis. Targeting of HER2 with drugs such as trastuzumab, lapatinib, or pertuzumab has led to clinical benefit in patients with both metastatic and early-stage HER2-amplified breast cancer. However, resistance and disease progression always occurs in patients with metastatic disease, and many patients with early-stage breast cancer experience recurrences despite adjuvant anti-HER2 therapy. As such, understanding the mechanisms of resistance to anti-HER2 therapy has important clinical implications.

Recent studies have identified mutations in PIK3CA, the gene encoding the catalytic subunit of Phosphatidylinositol 3 kinase (PI3K), as one mechanism of resistance to trastuzumab. However, such mutations are present in only a fraction of trastuzumab-resistant breast cancers. We therefore sought to uncover novel mechanisms of resistance to anti-HER2 therapy through an unbiased screen for kinases and kinase-related molecules that are able to rescue HER2-amplified breast cancer cells from HER2 inhibition.

We utilized a library of nearly 600 lentivirally-delivered open reading frames (ORFs) to constitutively express the coding sequence of each molecule individually in HER2-amplified BT474 breast cancer cells in arrayed high-throughput format. We conducted two parallel screens for the ability of each of these molecules to rescue cells from anti-HER2 therapy: one in which we treated the cells with a lapatinib-like drug that inhibits the kinase activity of HER2 and EGFR, and one in which we lentivirally delivered a short hairpin RNA that suppresses expression of HER2.

We identified those ORFs that restored viability of BT474 cells to greater than two standard deviations above the median of all ORFs in each screen. Multiple members of the MAPK and PI3K signaling pathways scored in both screens, serving to validate the approach. In addition, the survival kinases PIM1 and PRKACA scored robustly. Mechanistic studies suggest that these kinases may confer resistance by restoring the phosphorylation of, and thereby inactivating, the pro-apoptotic protein BAD. Consistent with this finding, overexpression of Bcl-xl, which is inhibited by BAD, also conferred resistance to lapatinib in HER2-amplified breast cancer cells. Furthermore, pharmacological blockade of Bcl-xl and Bcl-2 with ABT-263 enhanced lapatinib-induced killing of HER2-amplified breast cancer cells in vitro, and partially abrogated the rescue conferred by both PRKACA and PIM1. These findings suggest that combined inhibition of HER2 and the anti-apoptotic molecules Bcl-xl and Bcl-2 could enhance tumor cell eradication and prevent or delay the emergence of resistant disease.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-08-01.

Radiosensitization of breast cancer cells by TRAIL-endostatin-targeting gene therapy

One of the key issues in cancer radiotherapy research is to sensitize tumor cells to the cell killing effects of ionizing radiation while leaving normal tissues intact. One potential approach to achieve this is gene-radiotherapy, i.e. a combination of radiation therapy and gene therapy. It is to choose certain exogenous radiation-inducible regulatory genes, for example, early growth response-1 (Egr-1), and transcript its downstream tumor-therapeutic genes under ionizing radiation so as to kill the tumor cells synergistically by the expressed gene products together after transfection and irradiation exposure. In this study, we engineered a plasmid encoding both TRAIL and endostatin under the control of the radiation-inducible Egr-1 promoter, and evaluated its anti-tumor efficacy in combination with radiotherapy. Our plasmid showed significant efficacy in up-regulating the levels of TRAIL and endostatin proteins after transfected into breast cancer cells and exposed to X-ray irradiation. The detected cellular effects in vitro manifested that TRAIL-endostatin-based gene therapy could enhance radiosensitizing effects in breast cancer cells in terms of tumor cell growth inhibition, promoting apoptosis and the induction of cell cycle arrest. In summary, our results suggest that TRAIL-endostain-targeting approach might be a promising method to sensitize solid tumors to radiation therapy.

Routine and dynamic MR imaging study of lobular capillary hemangioma of the nasal cavity with comparison to inverting papilloma

BACKGROUND AND PURPOSE

Lobular capillary hemangioma is an uncommon lesion, and its MR imaging appearance has not been fully characterized. The purpose of this study was to determine the MR imaging features of nasal lobular capillary hemangioma and contrast its imaging characteristics to inverting papilloma.

MATERIALS AND METHODS

The MR imaging signals of 32 patients with histopathologically proven nasal lobular capillary hemangiomas and 53 patients with nasal inverted papillomas were retrospectively studied. The findings of dynamic contrast-enhanced MR imaging in 24 lobular capillary hemangiomas and in 53 inverted papillomas were also analyzed. The Monte Carlo exact test was used for comparison of the time-intensity curve patterns of lobular capillary hemangioma and inverted papilloma.

RESULTS

All lobular capillary hemangiomas appeared to be homogeneously isointense to gray matter on T1-weighted images. On T2-weighted images, all lesions showed heterogeneous hyperintensity, and a thin peripheral isointense or hypointense ring was seen in 28 patients. All lesions showed marked enhancement on enhanced images, with the exception of enhancement of the T2 isointense or hypointense ring. Forty-three (81.1%) inverted papillomas had moderate heterogeneous T2 signal intensity, and a characteristic "cerebriform" appearance was detected in 45 (84.91%) of 53 inverted papillomas. The time-intensity curves showed a washout pattern in 18 and a plateau pattern in 6 patients, whereas inverted papillomas showed a washout pattern in 12, a plateau pattern in 35, and a persistent pattern in 6 patients. There was a statistically significant difference as to time-intensity curve pattern between the 2 groups (P < .05).

CONCLUSIONS

Hyperintensity on T2-weighted images, marked enhancement of tumor with a nonenhancing thin peripheral ring, and a washout time-intensity curve pattern are characteristic MR imaging features of nasal lobular capillary hemangiomas.

Genetic analysis of the ELOVL6 gene polymorphism associated with type 2 diabetes mellitus

Recent animal studies have indicated that overexpression of the elongation of long-chain fatty acids family member 6 (Elovl6) gene can cause insulin resistance and β-cell dysfunction. These are the major factors involved in the development of type 2 diabetes mellitus (T2DM). To identify the relationship between single nucleotide polymorphisms (SNP) of ELOVL6 and T2DM pathogenesis, we conducted a case-control study of 610 Han Chinese individuals (328 newly diagnosed T2DM and 282 healthy subjects). Insulin resistance and islet first-phase secretion function were evaluated by assessment of insulin resistance in a homeostasis model (HOMA-IR) and an arginine stimulation test. Three SNPs of the ELOVL6 gene were genotyped with polymerase chain reaction-restriction fragment length polymorphism, with DNA sequencing used to confirm the results. Only genotypes TT and CT of the ELOVL6 SNP rs12504538 were detected in the samples. Genotype CC was not observed. The T2DM group had a higher frequency of the C allele and the CT genotype than the control group. Subjects with the CT genotype had higher HOMA-IR values than those with the TT genotype. In addition, no statistical significance was observed between the genotype and allele frequencies of the control and T2DM groups for SNPs rs17041272 and rs6824447. The study indicated that the ELOVL6 gene polymorphism rs12504538 is associated with an increased risk of T2DM, because it causes an increase in insulin resistance.

Abstract LB-255: Exome mutation burden predicts clinical outcome in ovarian cancer carrying mutated BRCA1 and BRCA2 genes

Reliable biomarkers predicting resistance or sensitivity to anti-cancer therapy are critical for oncologists to select proper therapeutic drugs in individual cancer patients. Ovarian and breast cancer patients carrying germline mutations in BRCA1 or BRCA2 genes are often sensitive to DNA damaging drugs and relative to non-mutation carriers present a favorable clinical outcome following therapy. Genome sequencing studies have shown a high number of mutations in the tumor genome in patients carrying BRCA1 or BRCA2 mutations (mBRCA). The present study used exome-sequencing and SNP 6 array data of The Cancer Genome Atlas (TCGA) to correlate the total exome mutation number (Nmut) to progression-free survival (PFS) and overall survival (OS) in the patients (n = 316) with high grade serous ovarian cancer (HGSOC) after debulking surgery and platinum-based chemotherapy. HGSOC in 70 patients of this cohort had either germlines or somatic mutations of BRCA1 or BRCA2 genes. The results revealed that the Nmut was significantly lower in the chemotherapy-resistant mBRCA HGSOC defined by progression within 6 months after completion of first line platinum-based chemotherapy. We found a significant association between low Nmut and shorter PFS and OS in mBRCA HGSOC by Cox regression and Kaplan-Meier analyses. The association was also significant when the analysis was limited to germline BRCA1 or BRCA2 mutated patients with SNP array-determined loss of heterozygosity of the BRCA1 or BRCA2 locus in the tumors. In the mBRCA HGSOC tumors, Nmut was correlated with the genome fraction with loss of heterozygosity and with number of telomeric allelic imbalance, genomic measures evaluating chromosomal instability. However, no significant association between Nmut and PFS or OS was found in HGSOC carrying wild-type BRCA1 and BRCA2 genes. These results suggest that in cancers with DNA repair deficiency caused by functional BRCA loss, higher versus lower Nmut may reflect the status of deficiency or rescue by alternative mechanism(s) for DNA repair, with lower Nmut predicting for resistance to DNA-damaging drugs in mBRCA HGSOC. Our observations are consistent with the new concept that BRCA1/2 critically regulate error-free repair of nucleotide damage to suppress mutation formation, and may imply an activation of alternative repair mechanism(s) capable of bypassing the BRCA defect and restoring error-free DNA repair.

Citation Format: Nicolai Juul Birkbak, Bose Kochupurakkal, Jose MG Izarzugaza, Yang Li, Joyce Liu, Zoltan Szallasi, Ursula Matulonis, Andrea L. Richardson, J Dirk Iglehart, Zhigang C. Wang. Exome mutation burden predicts clinical outcome in ovarian cancer carrying mutated BRCA1 and BRCA2 genes. [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 LB-255. doi:10.1158/1538-7445.AM2013-LB-255

Solitary fibrous tumor of the sinonasal cavity: CT and MR imaging findings

SUMMARY

SFT is a rare lesion of the sinonasal cavity. We retrospectively reviewed 5 patients with histopathologically proved sinonasal SFTs to determine their CT and MR imaging features. All patients underwent paranasal sinus CT and MR imaging. Four SFTs occurred in the nasal cavity, and 1, in the maxillary sinus. All SFTs had well-defined margins, and the mean maximum diameter was 55 mm. On nonenhanced CT, 5 SFTs appeared homogeneously isoattenuating to gray matter. The most common manifestations of bony involvement were bony remodeling and thinning. On MR imaging, 5 SFTs were isointense to gray matter on T1-weighted images, and the lesions were isointense in 3 and hypointense in 2 patients on T2-weighted images. The lesions showed heterogeneously marked enhancement on postenhanced MR images. Four patients underwent dynamic contrast-enhanced MR imaging, and the TICs showed a washout pattern. A familiarity with the imaging findings of sinonasal SFT may help to diagnose this entity.

Profiles of genomic instability in high-grade serous ovarian cancer predict treatment outcome

PURPOSE

High-grade serous cancer (HGSC) is the most common cancer of the ovary and is characterized by chromosomal instability. Defects in homologous recombination repair (HRR) are associated with genomic instability in HGSC, and are exploited by therapy targeting DNA repair. Defective HRR causes uniparental deletions and loss of heterozygosity (LOH). Our purpose is to profile LOH in HGSC and correlate our findings to clinical outcome, and compare HGSC and high-grade breast cancers.

EXPERIMENTAL DESIGN

We examined LOH and copy number changes using single nucleotide polymorphism array data from three HGSC cohorts and compared results to a cohort of high-grade breast cancers. The LOH profiles in HGSC were matched to chemotherapy resistance and progression-free survival (PFS).

RESULTS

LOH-based clustering divided HGSC into two clusters. The major group displayed extensive LOH and was further divided into two subgroups. The second group contained remarkably less LOH. BRCA1 promoter methylation was associated with the major group. LOH clusters were reproducible when validated in two independent HGSC datasets. LOH burden in the major cluster of HGSC was similar to triple-negative, and distinct from other high-grade breast cancers. Our analysis revealed an LOH cluster with lower treatment resistance and a significant correlation between LOH burden and PFS.

CONCLUSIONS

Separating HGSC by LOH-based clustering produces remarkably stable subgroups in three different cohorts. Patients in the various LOH clusters differed with respect to chemotherapy resistance, and the extent of LOH correlated with PFS. LOH burden may indicate vulnerability to treatment targeting DNA repair, such as PARP1 inhibitors.

The p110α and p110β isoforms of PI3K play divergent roles in mammary gland development and tumorigenesis

Class Ia phosphatidylinositol 3 kinase (PI3K) is required for oncogenic receptor-mediated transformation; however, the individual roles of the two commonly expressed class Ia PI3K isoforms in oncogenic receptor signaling have not been elucidated in vivo. Here, we show that genetic ablation of p110α blocks tumor formation in both polyoma middle T antigen (MT) and HER2/Neu transgenic models of breast cancer. Surprisingly, p110β ablation results in both increased ductal branching and tumorigenesis. Biochemical analyses suggest a competition model in which the less active p110β competes with the more active p110α for receptor binding sites, thereby modulating the level of PI3K activity associated with activated receptors. Our findings demonstrate a novel p110β-based regulatory role in receptor-mediated PI3K activity and identify p110α as an important target for treatment of HER2-positive disease.

CT and MR imaging findings of periorbital lipogranuloma developing after endoscopic sinus surgery

SUMMARY

Periorbital lipogranuloma is a rare complication after ESS and presently lacks specific imaging reports. The purpose of this study was to describe the CT and MR imaging features of periorbital lipogranuloma. We retrospectively reviewed 9 patients with histology-confirmed periorbital lipogranuloma. All 9 patients underwent CT and MR imaging. Five lipogranulomas were located in the right eyelid and 4 in the left eyelid, which extended into the extraconal space to some degree. The lesions displayed an irregular shape and had an ill-defined margin. Multiple, specked, or nodular foci containing fat were scattered within these lesions. The lesions demonstrated moderate heterogeneous contrast enhancement on contrast-enhanced MR imaging. The TICs showed a persistent pattern (type I) in 6 patients undergoing DCE MR imaging. Thus, an ill-defined, irregular-shaped periorbital mass with multiple foci containing fat, combined with an ESS history, can help to accurately diagnose this entity.

Imaging study of ossifying fibroma with associated aneurysmal bone cyst in the paranasal sinus

OBJECTIVE

To determine the CT and MR imaging features of ossifying fibroma with aneurysmal bone cyst of the paranasal sinus.

MATERIALS AND METHODS

We retrospectively reviewed 15 patients with histopathology-proven ossifying fibromas with aneurysmal bone cysts in the paranasal sinus. All 15 patients underwent CT and MR imaging. The following imaging features were reviewed: location, shape, margin, CT findings, and MR imaging appearances and time-intensity curve of dynamic contrast-enhanced MR imaging.

RESULTS

Ossifying fibromas occurred in the maxillary sinus in one patient, sphenoid sinus in 2, frontal sinus in 3, frontoethmoid sinuses in 3, and ethmoid sinus in 6 patients. Ossifying fibromas showed an elliptic-shape and aneurysmal bone cysts revealed a multicystic appearance, with well-demarcated margins. On unenhanced CT, ossifying fibromas appeared isodense to gray matter with scattered calcifications in nine, ground-glass appearance in 6 patients and aneurysmal bone cysts showed mixed density. Ossifying fibromas appeared isointense to gray matter in 12 and slightly hypointense in three patients on T1-weighted images, and isointense in 4 and hypointense in eleven patients on T2-weighted images, with moderate or marked enhancement after administration of contrast material. The time-intensity curves of eight ossifying fibromas exhibited a rapidly enhancing and rapid washout pattern. The intracystic components of aneurysmal bone cysts showed heterogeneous signal intensity on MR images, with fluid-fluid levels identified clearly by T2-weighted images, without enhancement. The periphery and septa of aneurysmal bone cysts appeared isointense on MR images, with marked enhancement.

CONCLUSIONS

Fluid-fluid levels within an elliptic-shape mass with scattered calcifications or ground-glass appearance is highly suggestive of this complicated entity in the paranasal sinus.