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Cullin-RING ubiquitin E3 ligase (CRLs) composed of four components including cullin scaffolds, adaptors, substrate receptors, and RING proteins mediates the ubiquitination of approximately 20% of cellular proteins that are involved in numerous biological processes. While CRLs deregulation contributes to the pathogenesis of many diseases, including cancer, how CRLs deregulation occurs is yet to be fully investigated. Here, we demonstrate that components of CRL3 and its transcriptional regulators are possible prognosis marker of neuroendocrine (NE) cancer. Analysis of Cancer Cell Line Encyclopedia (CCLE) through the CellMinerCDB portal revealed that expression of CRL3 scaffold Cullin 3 (CUL3) highly correlates with NE signature, and CUL3 silencing inhibited NE cancer proliferation. Moreover, subset of 151 BTB (Bric-a-brac, Tramtrack, Broad complex) domain-containing proteins that have dual roles as substrate receptors and adaptor subunits in CRL3, as well as the expression of transcription factors (TFs) that control the transcription of BTB genes were upregulated in NE cancer. Analysis using published ChIP-sequencing data in small cell lung cancer (SCLC), including NE or non-NE SCLC verified that gene promoter of candidates which show high correlation with NE signature enriched H3K27Ac. These observations suggest that CRL3 is a master regulator of NE cancer and knowledge of specifically regulated CRL3 genes in NE cancer may accelerate new therapeutic approaches.

Follicular variant papillary thyroid carcinoma (FVPTC) is a problematic entity. FVPTCs are often misdiagnosed by the standard fine needle aspiration (FNA); in addition, FVPTCs represent a mixed group of tumors with two biologically distinct subtypes: The indolent encapsulated FVPTC and the aggressive infiltrative FVPTC. Recent changes in guidelines suggests that FVPTC management may be improved if subtypes can be determined preoperatively. Preoperative assays, FNA, core needle biopsy (CNB), and ultrasonography (US) were compared for their ability to identify and subtype FVPTCs to determine the most appropriate test to manage FVPTCs. The preoperative assays and clinicopathologic variables of 255 resected FVPTCs cases at Samsung Medical Center between 2012 and 2016 were retrospectively evaluated. CNB had the overall best ability to manage FVPTCs with the highest rate of diagnosis indicating surgery, lowest rate of inconclusive results, high sensitivity (88.9%), specificity (87.7%), negative predictive value (97.0%), diagnostic odds ratio (DOR; 56.9), and excellent predictive ability (AUC 0.906) for differentiating FVPTC subtypes. US had a moderate DOR (12.8), good predictive ability (AUC 0.802), high sensitivity (75.0%) and specificity (81.0%). CNB and US both had significantly higher accuracy for discriminating FVPTC subtypes than FNA (AUC 0.908 and 0.877 > 0.671; p

Gastric inverted polyps (GIPs) are rare gastric polyps characterized by a submucosal inverted growth of mucosal components. Because of their rarity, they are not well characterized and are diagnostically challenging. We examined 12 cases of GIPs arising in 8 male and 4 female patients (mean age: 56 y). Most GIPs (11/12, 92%) occurred as a single, rounded subepithelial lesion in the body or fundus (mean size: 14.9 mm). Histologically, GIPs consisted of gastric-type glandular epithelium and smooth muscle component, growing in an endophytic manner; however, they displayed significant morphologic variations. We classified GIPs into 3 subtypes by the following features: communication with the mucosal surface, smooth muscle boundary, and tissue organization. The defining characteristics of type 1 were a mucosal communicating structure at the center and a well-defined smooth muscle boundary, resulting in a characteristic low-magnification morphology of a round vase. Type 2 had an organized glandular proliferation with smooth muscle boundary and no central communicating structure. Type 3 GIPs had no mucosal communicating structure or smooth muscle boundary; its key histologic feature was the lobular organization pattern produced by proliferations of cystic or hyperplastic glands and smooth muscle. All type 1 GIPs exhibited coexisting adenocarcinoma (3 cases) or stromal proliferation (3 cases). Three patients with type 2 GIP had separate adenocarcinoma. None of the type 3 GIPs had accompanying carcinoma. In conclusion, GIPs are a heterogenous group showing different morphology and clinical behavior. Notably, type 1 GIP could be considered a precancerous lesion with the potential to develop adenocarcinoma.

sProper dendrite morphogenesis and neuronal migration are crucial for cerebral cortex development and neural circuit formation. In this study, we sought to determine if the histone deacetylase HDAC6 plays a role in dendrite development and neuronal migration of pyramidal neurons during cerebral cortex development. It was observed that knockdown of HDAC6 leads to defective dendrite morphogenesis and abnormal Golgi polarization in vitro, and the expression of wild type cortactin or deacetyl-mimetic cortactin 9KR rescued the defective phenotypes of the HDAC6 knockdown neurons. This suggests that HDAC6 promotes dendritic growth and Golgi polarization through cortactin deacetylation in vitro. We also demonstrated that ectopic expression of SIRT2, a cytoplasmic NAD+ − dependent deacetylase, suppresses the defects of HDAC6 knockdown neurons. These results indicate that HDAC6 and SIRT2 may be functionally redundant during dendrite development. Neurons transfected with both HDAC6 and SIRT2 shRNA or acetyl-mimetic cortactin 9KQ showed slow radial migration compared to the control cells during cerebral cortex development. Furthermore, a large portion of cortactin 9KQ-expressing pyramidal neurons at layer II/III in the cerebral cortex failed to form an apical dendrite toward the pial surface and had an increased number of primary dendrites, and the percentage of neurons with dendritic Golgi decreased in cortactin 9KQ-expressing cells, compared to control neurons. Taken together, this study suggests that HDAC6 and SIRT2 regulate neuronal migration and dendrite development through cortactin deacetylation in vivo.

Background: Lymphopenia is frequently observed in advanced cancer patients even before initiation of systemic anti-cancer treatment. The aim of this study is to investigate the pre-treatment lymphopenia as a prognostic factor for breast cancer specific survival (BCSS), distant recurrence free survival (DRFS) in patients with early breast cancer (EBC) and overall survival (OS), OS2 (from diagnosis with stage IV to death) with metastatic breast cancer (MBC) in large-scaled early and metastatic breast cancer database cohort. Methods: We reviewed demographic, clinical, pathologic, and survival data from Yonsei Breast Cancer Center Registry. In large scaled database, 5252 patients who underwent surgery with stage I-III EBC at the Yonsei Cancer Center between 2006 and 2015 were included and 1481 patients who were newly diagnosed de novo or recurrent MBC were included. The pre-treatment lymphocyte count was obtained from complete blood count (CBC) assay before the initiation of any treatment. Lymphopenia was defined as an absolute lymphocyte count (ALC) < 1000/mm3. Clinicopathologic factors, such as human epidermal growth factor 2 (HER2) receptor, hormone receptor (HR) status and metastatic site, were reviewed. To evaluate the prognostic factors, Kaplan-Meier, log-rank, and Cox regression analysis were performed. Results: Of 5211 eligible EBC patients, 2690 (51.6%) stage I and 1857 (35.6%) stage II patients was included. De novo and recurrent MBC patients were 260 (31.0%) and 576 (69.0%). The incidences of pre-treatment lymphopenia were 3.0% (154/5211) in EBC and 14.5% (121/836) in MBC: 10 (3.9%) in de novo stage IV and 117 (19.3%) in recurrent stage IV. There was no difference in pre-treatment lymphopenia incidence among histologic subtypes in EBC cohort, but it was significantly higher in triple negative breast cancer (TNBC) in MBC. EBC patients with HBsAg positive showed higher incidence of pre-treatment lymphopenia than HBV negative patients (7.3% vs. 2.9%, p=0.003). In MBC cohort, patients with early distant recurrent (less than 2 year) disease (35.8%, p Conclusions: In this large-scaled and retrospectively analyzed a dataset, we showed highest incidence of pre-treatment lymphopenia in recurrent MBC, not affected by previous chemotherapy exposure. Pre-treatment lymphopenia was a significant poor prognostic factor in recurrent stage IV MBC, but not in EBC or de novo stage IV MBC. Citation Format: Jee Hung Kim, Min Hwan Kim, Gun Min Kim, Byeong-Woo Park, Young Up Cho, Seung Il Kim, Seho Park, Hyung Seok Park, Ji Ye Kim, Hyun Cheol Chung, Soonmyung Paik, Joohyuk Sohn. Comprehensive analysis of lymphopenia in large-scaled early and metastatic breast cancer database cohort [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-43.

Background The antibody-drug conjugate targeting HER2, DS8201 has shown clinical activity against breast cancer with low-level HER2 expression in early clinical trial. In this study, we investigated the clinical implication and prognostic impact of intermediate HER2 expression in the prospectively collected ER (+) early breast cancer (EBC) and metastatic breast cancer (MBC) cohorts. Methods We analyzed the prospectively collected database of EBC and MBC cohort patients in Yonsei Cancer Center. We defined patients with HER2 immunohistochemistry (IHC) 0~1+ as HER2-negative group, and IHC 2+ and in situ hybridization (ISH) negative as HER2-intermediate group. Only ER (+) patients with complete HER2 IHC and ISH status were selected, excluding HER2 IHC 3+ or ISH+ patients. A total of 2,657 early breast cancer and 535 metastatic breast cancer patients were finally analyzed. The clinical and pathological characteristics and survival outcome of the patients were compared between HER2-negative and HER2-intermediate group in each cohort. Results The 654 (24.6%) EBC patients and 166 (31.0%) MBC patients were classified as HER2-intermediate group. The HER2-intermediate patients were more common in PR negative (30.4% versus 22.6%, p< 0.001) and higher nuclear grade (grade 2 or 3) patients (25.7% versus 17.4%, p = 0.001) in EBC cohort and in age ≥ 55 patients (36.7% versus 27.4%, p = 0.001) in MBC cohort. Other characteristics were not different between two groups in both cohorts. The HER2-intermediate patients showed significantly poorer recurrence-free survival (RFS) than HER2-negative patients in EBC patients (p = 0.044), although the prognostic impact was not significant in the multivariate analysis. Of note, intermediate HER2 expression was associated with significantly poorer RFS in EBC patients (p = 0.007) of age ≥ 55, but did not affect the RFS in patients of age < 55. The intermediate HER2 expression independently predicted poorer RFS of EBC patients of age ≥ 55 (Hazard ratio [HR], 1.95; 95% Confidence interval [CI], 1.03-3.73; p = 0.042) in multivariate Cox regression analysis with adjustment of other prognostic factors, T stage, N stage, PR status, and histologic grade. In line with result of EBC cohort, intermediate HER2 expression was associated with poorer overall survival (OS) in MBC patients of age ≥ 55 (p = 0.037), not affecting OS in MBC patients of age < 55. Intermediate HER2 expression predicted significantly poorer OS in MBC patients of age ≥ 55 (HR, 1.45; 95% CI, 1.01-2.07; p = 0.044) independent from PR status, disease status (recurrent versus de novo stage IV), and visceral metastasis. Conclusion Our analysis demonstrates intermediate HER2 expression as an independent poor prognostic factor for ER (+) breast cancer patients with age ≥ 55 in both EBC and MBC cohorts. The clinical efficacy of new HER2-targeting antibody-drug conjugates needs to be validated in this high-risk subset of ER (+) breast cancer patients. Citation Format: Min Hwan Kim, Gun Min Kim, Jee Hung Kim, Ji Ye Kim, Hyung Seok Park, Seho Park, Young Up Cho, Byeong Woo Park, Seung Il Kim, Joo-Hyuk Sohn. Intermediate HER2 expression predicts poor prognosis in ER (+) breast cancer patients aged 55 and older [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-33.

Pyogenic granuloma is a benign vascular tumor of the skin or mucous membrane. One-third of pyogenic granulomas have been reported in the head and neck, but it is rarely present in the external auditory canal. Pyogenic granuloma mostly presents as a solitary granuloma, and only a few cases of multiple forms have been reported. This report describes a rare case of multiple pyogenic granulomas in the external auditory canal of a 36-year-old man along with a review of the literatures. Although it is very rare for PGs to occur in the EAC, it can be suspected in conditions such as after acute and/or chronic trauma, hormonal changes or systemic drug administration, rapid growth, and easy bleeding tendency with a friable surface. Some PGs may spontaneously resolve, but when they cause symptoms, excision is recommended for treatment and diagnosis. In the case of excision, the tumor should be excised down to the perichondrium level to prevent recurrence. Although PG mainly occurs in a solitary form, the present case shows a new clinical variation where multiple PGs were present in the EAC.

BackgroundThe trastuzumab biosimilar CT-P6 has demonstrated equivalent efficacy and comparable safety to reference trastuzumab (RTZ) in clinical trials of human epidermal growth factor receptor 2 (HER2)-positive early breast cancer (EBC). Here, we present the first real-world comparison of CT-P6 versus RTZ with dual HER2-targeted therapy for the neoadjuvant and palliative first-line treatment with HER2-positive EBC and metastatic breast cancer (MBC) patients in two tertiary hospitals in Korea.MethodsWe retrospectively investigated medical records in the Severance Breast Cancer Registry in Korea. We identified patients with HER2-positive EBC (n=254) who had received neoadjuvant chemotherapy with RTZ or CT-P6, plus pertuzumab, carboplatin and docetaxel (TCHP) and untreated stage IV MBC (n=103) who had received palliative first-line treatment with RTZ or CT-P6, plus pertuzumab and docetaxel (THP) between May 2014 and December 2019. The primary endpoints were pathologic complete response (pCR) in the EBC and progression-free survival (PFS) in the MBC cohort. Overall survival (OS), overall response rate (ORR), disease control rate (DCR), and cardiac safety were secondary endpoints.ResultsA similar percentage of EBC patients achieved a pCR with CT-P6 versus RTZ (74.4% [93/125]) vs 69.8% [90/129], p=0.411). For patients with MBC, median follow-up duration was 23.0 and 41.0 months for CT-P6 and RTZ groups, respectively; median PFS did not differ significantly between two groups (13.0 vs 18.0 months, 95% confidence intervals (CIs) 0.0-26.6 vs 11.3-24.7, p=0.976). The ORR, DCR, and cardiac safety profiles did not also show significant difference efficacy outcomes between two groups.ConclusionsThese real-world data suggest that biosimilar trastuzumab CT-P6 has similar effectiveness and cardiac safety to RTZ in HER2-positive EBC and MBC patients, when administered as part of dual HER2-targeted therapy with pertuzumab plus chemotherapy in the neoadjuvant or palliative setting.

Extreme responders to anticancer therapy are rare among advanced breast cancer patients. Researchers, however, have yet to investigate treatment responses therein on the whole exome level. We performed whole exome analysis to characterize the genomic landscape of extreme responders among metastatic breast cancer patients. Clinical samples were obtained from breast cancer patients who showed exceptional responses to anti-HER2 therapy or hormonal therapy and from those who did not. Matched breast tumor tissue (somatic DNA) and blood samples (germline DNA) were collected from a total of 30 responders and 15 non-responders. Whole exome sequencing using Illumina HiSeq2500 was performed for all 45 patients (90 samples). Somatic single nucleotide variants (SNVs), indels, and copy number variants (CNVs) were identified for the genomes of each patient. Group-specific somatic variants and mutational burden were statistically analyzed. Sequencing of cancer exomes for all patients revealed 1839 somatic SNVs (1661 missense, 120 nonsense, 43 splice-site, 15 start/stop-lost) and 368 insertions/deletions (273 frameshift, 95 in-frame), with a median of 0.7 mutations per megabase (range, 0.08 to 4.2 mutations per megabase). Responders harbored a significantly lower nonsynonymous mutational burden (median, 26 vs. 59, P = 0.02) and fewer CNVs (median 13.6 vs. 97.7, P = 0.05) than non-responders. Multivariate analyses of factors influencing progression-free survival showed that a high mutational burden and visceral metastases were significantly related with disease progression. Extreme responders to treatment for metastatic breast cancer are characterized by fewer nonsynonymous mutations and CNVs., Lim, Kim and Jung et al. report a whole-exome sequence analysis of 30 Korean patients showing extreme treatment responses for metastatic breast cancer. They find that compared to non-responders, extreme responders have fewer nonsynonymous mutations and copy number variants.

Diffuse involvement of colorectal lymphoma masquerading as colitis is a very rare presentation of primary colorectal lymphoma. Detecting occult lymphoma is difficult in the setting of diffuse colonic involvement with no definite mass and inflammatory mucosal changes. We encountered a case of diffuse-type primary colorectal lymphoma simulating ulcerative colitis in a previously healthy 31-year-old woman. Despite multiple mucosal biopsies, the biopsy diagnosis was not made due to unawareness of atypical lymphocytes admixed with dense lymphoplasmacytic infiltration. The present case emphasizes the importance of being aware of this rare presentation of primary colorectal lymphoma in order to avoid misdiagnosis.

Our aim is to explore differences in Hector Battifora mesothelial-1 (HBME-1), cytokeratin-19 (CK19), Galectin-3 (Gal-3), and CD56 expression in infiltrative follicular variants of papillary carcinoma (IFVPTC) and encapsulated follicular variants of papillary carcinoma (EFVPTC) and to provide clues for distinguishing the two subtypes preoperatively. Tissue microarrays from 100 EFVPTC (45 non-invasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP) and 55 invasive EFVPTCs), 43 IFVPTCs, and 64 follicular neoplasms (FN) were immunostained with HBME-1, CK19, Gal-3, and CD56. Each case was scored 1 point for every positive result. Immunohistochemical expression was not significantly different in invasive EFVPTC and NIFTP, except for that of HBME-1. HBME-1, CK19, Gal-3, and CD56 expression were significantly higher in IFVPTC than in EFVPTC. At the cutoff of 3 points, the score method had special diagnostic value for differentiating IFVPTC from EFVPTC and FN and for predicting lymph node metastasis. Scoring of immunohistochemistry results may be applied to core biopsy or cell blocks to assist ultrasonographic, cytologic and molecular tests in differentiating IFVPTC and EFVPTC preoperatively, possibly appropriately guiding EFVPTC preoperatively for limited operation or active surveillance.

Hypothalamic neurons including proopiomelanocortin (POMC)-producing neurons regulate body weights. The non-motile primary cilium is a critical sensory organelle on the cell surface. An association between ciliary defects and obesity has been suggested, but the underlying mechanisms are not fully understood. Here we show that inhibition of ciliogenesis in POMC-expressing developing hypothalamic neurons, by depleting ciliogenic genes IFT88 and KIF3A, leads to adulthood obesity in mice. In contrast, adult-onset ciliary dysgenesis in POMC neurons causes no significant change in adiposity. In developing POMC neurons, abnormal cilia formation disrupts axonal projections through impaired lysosomal protein degradation. Notably, maternal nutrition and postnatal leptin surge have a profound impact on ciliogenesis in the hypothalamus of neonatal mice; through these effects they critically modulate the organization of hypothalamic feeding circuits. Our findings reveal a mechanism of early life programming of adult adiposity, which is mediated by primary cilia in developing hypothalamic neurons., Ciliary defects and obesity has been associated, but the underlying mechanism is unclear. Here, the authors show that inhibition of ciliogenesis in POMC neurons during development results in lysosomal protein degradation-dependent axonal disruption and adult obesity in mice.

Although Ki67 labeling index is a potential predictive marker for chemotherapy benefit, its clinical utility has been limited by the lack of a standard scoring method resulting in poor interobserver reproducibility. Especially, there is no consensus on the use of average versus hotspot score for reporting. In order to determine the best method for Ki67 scoring and validate manual scoring method proposed by the International Ki67 Working Group (IKWG), we systematically compared average versus hotspot score in 240 cases with a public domain image analysis program QuPath. We used OncotypeDx Recurrence Score (RS) as a benchmark to compare the potential clinical utility of each scoring methods. Both average and hotspot scores showed statistically significant but only modest correlation with OncotypeDx RS. Only hotspot score could meaningfully distinguish RS low-risk versus high-risk patients. However, hotspot score was less reproducible limiting its clinical utility. In summary, our data demonstrate that utility of the Ki67 labeling index is influenced by the choice of scoring method.

Foot-and-mouth disease (FMD) is considered one of the highly contagious viral infections affecting livestock. In Korea, an FMD vaccination policy has been implemented nationwide since 2010 for the prevention and control of FMD. Since the vaccines are imported from various countries, standardized quality control measures are critical. In this study, we aimed to validate a high-performance liquid chromatography (HPLC) device in the Animal and Plant Quarantine Agency lab and identify an appropriate FMD vaccine pretreatment method for HPLC&mdash, a simple, reliable, and practical method to measure antigen content. Based on the analyses of specificity, linearity, accuracy, repeatability, intermediate precision, limits of detection, and limits of quantification using FMD standard samples, we validated the method using a standard material. Overall, we confirmed that the HPLC technique is effective for the quantitative assessment of the FMD virus 146S antigen in Korea. Using commercial FMD vaccines, we evaluated three separation methods and identified the method using n-pentanol and trichloroethylene as optimal for HPLC analysis. Our HPLC method was effective for the analytical detection of the antigen content in FMD vaccine, and it may be useful as a reference method for national lot-release testing.

Objective Kallikrein 5 (KLK5), which is frequently observed in normal cervico-vaginal fluid, is known to be related to prognosis in several solid tumors. We investigated the prognostic significance of KLK5 in uterine cervical cancer using tumor tissue microarray and immunohistochemistry staining. Methods We analyzed samples of 165 patients with uterine cervical cancer who received definitive radiation therapy between 2004 and 2012. We divided patients into two groups stratified by their KLK5 activity by immunohistochemistry staining: negative/weak (0–1+) (n=120 patients) and moderate/strong (2–3+) group (n=45 patients). Patient and tumor characteristics, patterns of failure, and survival outcomes were compared. Univariable and multivariable analyses were performed to identify prognostic factors. Results Patients with KLK5 2–3+ were younger (median: 52 vs. 60 years) and had frequent paraaortic lymph node involvement (40.0% vs. 18.3%) than those with KLK5 0–1+. With a median follow-up of 60.8 (interquartile range, 47.5–77.9) months, patients with KLK5 2–3+ had inferior 5-year locoregional recurrence-free survival and distant metastasis-free survival of 61.7% (vs. 77.5% in KLK5 0–1+ group) and 59.4% (vs. 72.8% in the KLK5 0–1+ group), respectively (all p

Purpose Dose-dense chemotherapy (DD-CT) is a preferred (neo)adjuvant regimen in early breast cancer (BC). Although the results of reported randomized trials are conflicting, a recent metaanalysis showed improved overall and disease-free survival with DD-CT compared to conventional schedules. However, no DD-CT safety data for Korean BC patients are available. This phase II study was conducted to evaluate the safety and efficacy of pegteograstim in Korean BC patients receiving DD-CT. Materials and methods Patients with operable (stage I-III), histologically confirmed BC received four cycles of intravenous doxorubicin (60 mg/m2) and cyclophosphamide (600 mg/m2) on day 1 every 2 weeks as neoadjuvant or adjuvant therapy. Pegteograstim (6.0 mg) was administered subcutaneously on day 2 of each cycle. The primary endpoint was the incidence of febrile neutropenia (FN). The secondary endpoints were safety and tolerability. Results Of 63 patients, one (1.6%) developed FN during all cycles of DD-CT. Dose delay was observed in four patients (6.3%) and dose reduction in two (3.2%) during DD-CT. Frequent adverse events (AEs) were nausea, alopecia, generalized muscle weakness, myalgia, mucositis, anorexia, dyspepsia, and diarrhea; most AEs were related to chemotherapy. Grade 3-4 AEs were reported in five of 63 patients (7.9%), and all grade 3 and 4 AEs were related to chemotherapy. Adverse drug reactions possibly linked to pegteograstim were abdominal pain, bone pain, myalgia, generalized muscle weakness, and headache in five of 63 patients (7.9%). Conclusion Dose-dense AC (doxorubicin/cyclophosphamide) chemotherapywith pegteograstim support is a tolerable and safe regimen in Korean early BC patients.

An attention guided convolutional neural network (CNN) for the classification of breast cancer histopathology images is proposed. Neural networks are generally applied as black box models and often the network’s decisions are difficult to interpret. Making the decision process transparent, and hence reliable is important for a computer-assisted diagnosis (CAD) system. Moreover, it is crucial that the network’s decision be based on histopathological features that are in agreement with a human expert. To this end, we propose to use additional region-level supervision for the classification of breast cancer histopathology images using CNN, where the regions of interest (RoI) are localized and used to guide the attention of the classification network simultaneously. The proposed supervised attention mechanism specifically activates neurons in diagnostically relevant regions while suppressing activations in irrelevant and noisy areas. The class activation maps generated by the proposed method correlate well with the expectations of an expert pathologist. Moreover, the proposed method surpasses the state-of-the-art on the BACH microscopy test dataset (part A) with a significant margin.

Proper dendrite development is essential for establishing neural circuitry, and Rho GTPases play key regulatory roles in this process. From mouse brain lysates, we identified Brefeldin A-inhibited guanine exchange factor 2 (BIG2) as a novel Rho GTPase regulatory protein involved in dendrite growth and maintenance. BIG2 was highly expressed during early development, and knockdown of the ARFGEF2 gene encoding BIG2 significantly reduced total dendrite length and the number of branches. Expression of the constitutively active ADP-ribosylation factor 1 ARF1 Q71L rescued the defective dendrite morphogenesis of ARFGEF2-null neurons, indicating that BIG2 controls dendrite growth and maintenance by activating ARF1. Moreover, BIG2 co-localizes with the Golgi apparatus and is required for Golgi deployment into major dendrites in cultured hippocampal neurons. Simultaneous overexpression of BIG2 and ARF1 activated RhoA, and treatment with the RhoA activator lysophosphatidic acid in neurons lacking BIG2 or ARF1 increased the number of cells with dendritic Golgi, suggesting that BIG2 and ARF1 activate RhoA to promote dendritic Golgi polarization. mDia1 was identified as a downstream effector of BIG2-ARF1-RhoA axis, mediating Golgi polarization and dendritic morphogenesis. Furthermore, in utero electroporation of ARFGEF2 shRNA into the embryonic mouse brain confirmed an in vivo role of BIG2 for Golgi deployment into the apical dendrite. Taken together, our results suggest that BIG2-ARF1-RhoA-mDia1 signaling regulates dendritic Golgi polarization and dendrite growth and maintenance in hippocampal neurons.

Poly (ADP-ribose) polymerase 1 inhibitors (PARPi) are used to treat recurrent ovarian cancer (OC) patients due to greater survival benefits and minimal side effects, especially in those patients with complete or partial response to platinum-based chemotherapy. However, acquired resistance of platinum-based chemotherapy leads to the limited efficacy of PARPi monotherapy in most patients. Twist is recognized as a possible oncogene and contributes to acquired cisplatin resistance in OC cells. In this study, we show how Twist knockdown cisplatin-resistant (CisR) OC cells blocked DNA damage response (DDR) to sensitize these cells to a concurrent treatment of cisplatin as a platinum-based chemotherapy agent and niraparib as a PARPi on in vitro two-dimensional (2D) and three-dimensional (3D) cell culture. To investigate the lethality of PARPi and cisplatin on Twist knockdown CisR OC cells, two CisR cell lines (OV90 and SKOV3) were established using step-wise dose escalation method. In addition, in vitro 3D spheroidal cell model was generated using modified hanging drop and hydrogel scaffolds techniques on poly-2-hydroxylethly methacrylate (poly-HEMA) coated plates. Twist expression was strongly correlated with the expression of DDR proteins, PARP1 and XRCC1 and overexpression of both proteins was associated with cisplatin resistance in OC cells. Moreover, combination of cisplatin (Cis) and niraparib (Nira) produced lethality on Twist-knockdown CisR OC cells, according to combination index (CI). We found that Cis alone, Nira alone, or a combination of Cis+Nira therapy increased cell death by suppressing DDR proteins in 2D monolayer cell culture. Notably, the combination of Nira and Cis was considerably effective against 3D-cultures of Twist knockdown CisR OC cells in which Endoplasmic reticulum (ER) stress is upregulated, leading to initiation of mitochondrial-mediated cell death. In addition, immunohistochemically, Cis alone, Nira alone or Cis+Nira showed lower ki-67 (cell proliferative marker) expression and higher cleaved caspase-3 (apoptotic marker) immuno-reactivity. Hence, lethality of PARPi with the combination of Cis on Twist knockdown CisR OC cells may provide an effective way to expand the therapeutic potential to overcome platinum-based chemotherapy resistance and PARPi cross resistance in OC.