Ago2/CAV1 interaction potentiates metastasis via controlling Ago2 localization and miRNA action.

Ago2 differentially regulates oncogenic and tumor-suppressive miRNAs in cancer cells. This discrepancy suggests a secondary event regulating Ago2/miRNA action in a context-dependent manner. We show here that a positive charge of Ago2 K212, that is preserved by SIR2-mediated Ago2 deacetylation in cancer cells, is responsible for the direct interaction between Ago2 and Caveolin-1 (CAV1). Through this interaction, CAV1 sequesters Ago2 on the plasma membranes and regulates miRNA-mediated translational repression in a compartment-dependent manner. Ago2/CAV1 interaction plays a role in miRNA-mediated mRNA suppression and in miRNA release via extracellular vesicles (EVs) from tumors into the circulation, which can be used as a biomarker of tumor progression. Increased Ago2/CAV1 interaction with tumor progression promotes aggressive cancer behaviors, including metastasis. Ago2/CAV1 interaction acts as a secondary event in miRNA-mediated suppression and increases the complexity of miRNA actions in cancer.

In situ HER2 RNA expression as a predictor of pathologic complete response of HER2-positive breast cancer patients receiving neoadjuvant chemotherapy and anti-HER2 targeted treatment.

BACKGROUND: Immunohistochemistry (IHC) and in situ hybridization (ISH) remain standard biomarkers for therapeutic decisions in human epidermal growth factor 2 (HER2)-positive breast cancers (BCs); however, they are insufficient to explain the heterogeneous anti-HER2 response. METHODS: We aimed to investigate the correlation of in situ HER2 RNA expression (isHRE), using RNAscope, with HER2 biomarkers and the impact of isHRE on the pathological complete response (pCR) rates of 278 patients with HER2 IHC/fluorescence ISH (FISH)-positive BC receiving neoadjuvant chemotherapy and anti-HER2 targeted treatment (NCTT). RESULTS: We validated HER2 RNAscope scoring as a semiquantitative method to determine isHRE and showed a positive correlation between RNAscope scores and pCR rates, with particularly different rates between patients with a score of 5 versus 1-4 BCs (66.7% vs. 15.9%, p < 0.0001). There were higher RNAscope scores and pCR rates in patients with HER2 IHC 3 + versus IHC 2+/FISH + BCs and HER2 RNAscope scores and pCR rates showed similar non-linear positive correlations with HER2 copy numbers and HER2/centromere 17 ratios. Moreover, in each HER2-positive IHC/FISH category, higher pCR rates were observed in patients with RNAscope scores of 5 versus 1-4 BC. Patients achieving pCR had BCs with notably higher HER2 RNAscope scores. Multivariate analysis identified HER2 RNAscope 5 as a strong pCR predictor [odds ratio = 10.865, p < 0.001]. The combined impact of multivariate analysis-defined pCR predictors demonstrated that a higher pCR rate was observed in patients with a score of 5 versus a score of 1-4 BCs regardless of the status of hormone receptor and mono-or dual anti-HER2 blockade. CONCUSIONS: Our results demonstrated that high isHRE (RNAscope score 5) is a strong pCR predictor in patients with HER2-positive BCs receiving NCTT, highlighting the complementary role of isHRE in stratifying HER2 status in tissue. Such stratification is relevant to anti-HER2 therapeutic efficacy, particularly using the cutoff of score 1-4 versus 5.

Interaction of base excision repair gene polymorphism and estrogen-DNA adducts in breast cancer risk among East Asian women.

PURPOSE: In East Asia, the incidence of breast cancer has been increasing rapidly, particularly among premenopausal women. An elevated ratio of estrogen-DNA adducts was linked to a higher risk of breast cancer. The present study explored the influence of the interaction between base excision repair (BER) gene polymorphisms and estrogen-DNA adducts on breast cancer risk. METHODS: We conducted a case-control study comprising healthy volunteers and individuals with benign breast disease (control arm, n = 176) and patients with invasive carcinoma or carcinoma in situ (case arm, n = 177). Genotyping for BER-related genes, including SMUG1, OGG1, ERCC5, and APEX1, was performed. A logistic regression model, incorporating interactions between gene polymorphisms, estrogen-DNA adduct ratio, and clinical variables, was used to identify the risk factors for breast cancer. RESULTS: Univariate analysis indicated marginal associations between breast cancer risk and APEX1 rs1130409 T > G (P = 0.057) and APEX1 rs1760944 T > G (P = 0.065). Multivariate regression analysis revealed significant associations with increased breast cancer risk for APEX1_rs1130409 (GT/GG versus TT) combined with a natural logarithmic value of the estrogen-DNA adduct ratio (estimated OR 1.164, P = 0.023) and premenopausal status with an estrogen-DNA adduct ratio > 2.93 (estimated OR 2.433, P = 0.001). CONCLUSION: APEX1_rs1130409 (GT/GG versus TT) polymorphisms, which are related to decreased BER activity, combined with an increased ratio of estrogen-DNA adducts, increase the risk of breast cancer in East Asian women.

A novel computer-assisted tool for 3D imaging of programmed death-ligand 1 expression in immunofluorescence-stained and optically cleared breast cancer specimens.

BACKGROUND: Programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are the two most common immune checkpoints targeted in triple-negative breast cancer (BC). Refining patient selection for immunotherapy is non-trivial and finding an appropriate digital pathology framework for spatial analysis of theranostic biomarkers for PD-1/PD-L1 inhibitors remains an unmet clinical need. METHODS: We describe a novel computer-assisted tool for three-dimensional (3D) imaging of PD-L1 expression in immunofluorescence-stained and optically cleared BC specimens (n = 20). The proposed 3D framework appeared to be feasible and showed a high overall agreement with traditional, clinical-grade two-dimensional (2D) staining techniques. Additionally, the results obtained for automated immune cell detection and analysis of PD-L1 expression were satisfactory. RESULTS: The spatial distribution of PD-L1 expression was heterogeneous across various BC tissue layers in the 3D space. Notably, there were six cases (30%) wherein PD-L1 expression levels along different layers crossed the 1% threshold for admitting patients to PD-1/PD-L1 inhibitors. The average PD-L1 expression in 3D space was different from that of traditional immunohistochemistry (IHC) in eight cases (40%). Pending further standardization and optimization, we expect that our technology will become a valuable addition for assessing PD-L1 expression in patients with BC. CONCLUSION: Via a single round of immunofluorescence imaging, our approach may provide a considerable improvement in patient stratification for cancer immunotherapy as compared with standard techniques.

SCEL regulates switches between pro-survival and apoptosis of the TNF-α/TNFR1/NF-κB/c-FLIP axis to control lung colonization of triple negative breast cancer.

BACKGROUND: Patients with metastatic triple-negative breast cancer (mTNBC) have a higher probability of developing visceral metastasis within 5 years after the initial diagnosis. Therefore, a deeper understanding of the progression and spread of mTNBC is urgently needed. METHODS: The isobaric tag for relative and absolute quantitation (iTRAQ)-based LC-MS/MS proteomic approach was applied to identify novel membrane-associated proteins in the lung-tropic metastatic cells. Public domain datasets were used to assess the clinical relevance of the candidate proteins. Cell-based and mouse models were used for biochemical and functional characterization of the protein molecule Sciellin (SCEL) identified by iTRAQ to elucidate its role and underlying mechanism in promoting lung colonization of TNBC cells. RESULTS: The iTRAQ-based LC-MS/MS proteomic approach identified a membrane-associated protein SCEL that was overexpressed in the lung-tropic metastatic cells, and its high expression was significantly correlated with the late-stage TNBC and the shorter survival of the patients. Downregulation of SCEL expression significantly impaired the 3D colony-forming ability but not the migration and invasion ability of the lung colonization (LC) cells. Knockdown of SCEL reduced TNF-α-induced activation of the NF-κB/c-FLIP pro-survival and Akt/Erk1/2 growth signaling pathways in the LC cells. Specifically, knockdown of SCEL expression switched TNF-α-mediated cell survival to the caspase 3-dependent apoptosis. Conversely, ectopic expression of SCEL promoted TNF-α-induced activation of NF-κB/c-FLIP pro-survival and Akt/Erk1/2 pro-growth signaling pathway. The result of co-immunoprecipitation (Co-IP) and GST pull-down assay showed that SCEL could interact with TNFR1 to promote its protein stability. The xenograft mouse model experiments revealed that knockdown of SCEL resulted in increase of caspase-3 activity, and decrease of ki67 and TNFR1 expression as well as increase of tumor-associated macrophages in the metastatic lung lesions. Clinically, SCEL expression was found to be positively correlated with TNFR1 in TNBC tissues. Lastly, we showed that blocking TNF-α-mediated cell survival signaling by adalimumab effectively suppressed the lung colonization of the SCEL-positive, but not the SCEL-downregulated LC cells in the tail-vein injection model. CONCLUSIONS: Our findings indicate that SCEL plays an essential role in the metastatic lung colonization of TNBC by promoting the TNF-α/TNFR1/NF-κB/c-FLIP survival and Akt/Erk1/2 proliferation signaling. Thus, SCEL may serve as a biomarker for adalimumab treatment of TNBC patients.

High rate of postoperative upstaging of ductal carcinoma in situ when prioritizing ultrasound evaluation of mammography-detected lesions: a single-center retrospective cohort study.

BACKGROUND: The initial diagnosis of ductal carcinoma in situ (DCIS) can be upstaged to invasive cancer after definitive surgery. This study aimed to identify risk factors for DCIS upstaging using routine breast ultrasonography and mammography (MG) and to propose a prediction model. METHODS: In this single-center retrospective study, patients initially diagnosed with DCIS (January 2016-December 2017) were enrolled (final sample size = 272 lesions). Diagnostic modalities included ultrasound-guided core needle biopsy (US-CNB), MG-guided vacuum-assisted breast biopsy, and wire-localized surgical biopsy. Breast ultrasonography was routinely performed for all patients. US-CNB was prioritized for lesions visible on ultrasound. Lesions initially diagnosed as DCIS on biopsy with a final diagnosis of invasive cancer at definitive surgery were defined as "upstaged." RESULTS: The postoperative upstaging rates were 70.5%, 9.7%, and 4.8% in the US-CNB, MG-guided vacuum-assisted breast biopsy, and wire-localized surgical biopsy groups, respectively. US-CNB, ultrasonographic lesion size, and high-grade DCIS were independent predictive factors for postoperative upstaging, which were used to construct a logistic regression model. Receiver operating characteristic analysis showed good internal validation (area under the curve = 0.88). CONCLUSIONS: Supplemental screening breast ultrasonography possibly contributes to lesion stratification. The low upstaging rate for ultrasound-invisible DCIS diagnosed by MG-guided procedures suggests that it is unnecessary to perform sentinel lymph node biopsy for lesions invisible on ultrasound. Case-by-case evaluation of DCIS detected by US-CNB can help surgeons determine if repeating biopsy with vacuum-assisted breast biopsy is necessary or if sentinel lymph node biopsy should accompany breast-preserving surgery. TRIAL REGISTRATION: This single-center retrospective cohort study was conducted with the approval of the institutional review board of our hospital (approval number 201610005RIND). As this was a retrospective review of clinical data, it was not registered prospectively.

Impact of BRCA mutation on the survival and risk of contralateral breast cancer in Asian breast cancer patients.

PURPOSE: Breast cancer is increasing around the globe, including Asia. We aimed to examine the survival and risk of contralateral breast cancer (CBC) in Asian breast cancer patients with BRCA mutations. METHODS: A total of 128 breast cancer patients with germline BRCA mutations and 4,754 control breast cancer patients were enrolled. Data on clinical-pathologic characteristics, survival, and CBC were collected from the medical record. The rates of survival and CBC were estimated by Kaplan-Meier method. RESULTS: The mean age of onset in BRCA mutation carriers was significantly younger than control patients (BRCA vs. Non-BRCA: 43.9 vs. 53.2 years old). BRCA mutation carriers had a higher proportion of triple-negative breast cancer (TNBC) (52%) than control patients (12%, p < 0.001). The risk of CBC was significantly higher in BRCA mutation patients than in control cases (hazard ratio (HR) = 3.95, 95% CI 2.71-5.75); when stratified by genotype, the HRs (95%CI) were 4.84 (3.00-7.82) for BRCA1 and 3.13 (1.78-5.49) for BRCA2 carriers, respectively. Moreover, BRCA1 mutation patients with triple-negative breast cancer (TNBC) as their first breast cancer had the highest risk of CBC (HR = 5.55, 95% CI 3.29-9.34). However, we did not observe any differences in relapse-free survival and overall survival between mutation carriers and control patients. CONCLUSION: Our study suggest that BRCA patients had a significantly higher risk of developing CBC, particularly for BRCA1 mutation carriers with TNBC as the first breast cancer.

Biomarker discovery in highly invasive lung cancer cell through proteomics approaches.

Lung cancer is one of the leading causes of cancer-related death worldwide. The most common type of lung cancer is non-small cell lung cancer (NSCLC). When NSCLC is detected, patients are typically already in a metastatic stage. Metastasized cancer is a major obstacle of effective treatment and understanding the mechanisms underlying metastasis is critical to treat cancer. Herein, we selected an invasive subpopulation from the human lung cancer cell line A549 using the transwell system and named it as A549-I5. Invasive and migratory activities of this cell line were analysed using wound healing, invasion, and migration assays. In addition, epithelial-mesenchymal transition (EMT) markers, such as Snail 1, Twist, Vimentin, N-cadherin and E-cadherin, were assessed through immunoblotting. In comparison to A549 cells, the invasive A549-I5 lung cancer cells had enhanced invasiveness, motility and EMT marker expression. Proteomic analysis identified 83 significantly differentially expressed proteins in A549-I5 cells. These identified proteins were classified according to their cellular functions and most were involved in cytoskeleton, redox regulation, protein degradation and protein folding. In summary, our results provide potential diagnostic markers and therapeutic candidates for the treatment of NSCLC metastasis. SIGNIFICANCE OF THE STUDY: When NSCLC is detected, most patients are already in a metastatic stage. Herein, we selected an invasive subpopulation from a human lung cancer cell line which had increased EMT markers as well as high wound healing, invasion and migration abilities. Proteomic analysis identified numerous proteins associated with functions in cytoskeleton, redox regulation, protein degradation and protein folding that were differentially expressed in these cells. These results may provide potential diagnostic markers and therapeutic candidates for the treatment of NSCLC metastasis.

Overexpression of Adiponectin Receptor 1 Inhibits Brown and Beige Adipose Tissue Activity in Mice.

Adult humans and mice possess significant classical brown adipose tissues (BAT) and, upon cold-induction, acquire brown-like adipocytes in certain depots of white adipose tissues (WAT), known as beige adipose tissues or WAT browning/beiging. Activating thermogenic classical BAT or WAT beiging to generate heat limits diet-induced obesity or type-2 diabetes in mice. Adiponectin is a beneficial adipokine resisting diabetes, and causing "healthy obese" by increasing WAT expansion to limit lipotoxicity in other metabolic tissues during high-fat feeding. However, the role of its receptors, especially adiponectin receptor 1 (AdipoR1), on cold-induced thermogenesis in vivo in BAT and in WAT beiging is still elusive. Here, we established a cold-induction procedure in transgenic mice over-expressing AdipoR1 and applied a live 3-D [18F] fluorodeoxyglucose-PET/CT (18F-FDG PET/CT) scanning to measure BAT activity by determining glucose uptake in cold-acclimated transgenic mice. Results showed that cold-acclimated mice over-expressing AdipoR1 had diminished cold-induced glucose uptake, enlarged adipocyte size in BAT and in browned WAT, and reduced surface BAT/body temperature in vivo. Furthermore, decreased gene expression, related to thermogenic Ucp1, BAT-specific markers, BAT-enriched mitochondrial markers, lipolysis and fatty acid oxidation, and increased expression of whitening genes in BAT or in browned subcutaneous inguinal WAT of AdipoR1 mice are congruent with results of PET/CT scanning and surface body temperature in vivo. Moreover, differentiated brown-like beige adipocytes isolated from pre-adipocytes in subcutaneous WAT of transgenic AdipoR1 mice also had similar effects of lowered expression of thermogenic Ucp1, BAT selective markers, and BAT mitochondrial markers. Therefore, this study combines in vitro and in vivo results with live 3-D scanning and reveals one of the many facets of the adiponectin receptors in regulating energy homeostasis, especially in the involvement of cold-induced thermogenesis.

Progesterone receptor membrane component 1 is involved in oral cancer cell metastasis.

Cancer metastasis is a common cause of failure in cancer therapy. However, over 60% of oral cancer patients present with advanced stage disease, and the five-year survival rates of these patients decrease from 72.6% to 20% as the stage becomes more advanced. In order to manage oral cancer, identification of metastasis biomarker and mechanism is critical. In this study, we use a pair of oral squamous cell carcinoma lines, OC3, and invasive OC3-I5 as a model system to examine invasive mechanism and to identify potential therapeutic targets. We used two-dimensional differential gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) to examine the global protein expression changes between OC3 and invasive OC3-I5. A proteomic study reveals that invasive properties alter the expression of 101 proteins in OC3-I5 cells comparing to OC3 cells. Further studies have used RNA interference technique to monitor the influence of progesterone receptor membrane component 1 (PGRMC1) protein in invasion and evaluate their potency in regulating invasion and the mechanism it involved. The results demonstrated that expression of epithelial-mesenchymal transition (EMT) markers including Twist, p-Src, Snail1, SIP1, JAM-A, vimentin and vinculin was increased in OC3-I5 compared to OC3 cells, whereas E-cadherin expression was decreased in the OC3-I5 cells. Moreover, in mouse model, PGRMC1 is shown to affect not only migration and invasion but also metastasis in vivo. Taken together, the proteomic approach allows us to identify numerous proteins, including PGRMC1, involved in invasion mechanism. Our results provide useful diagnostic markers and therapeutic candidates for the treatment of oral cancer invasion.

Disparity in Tumor Immune Microenvironment of Breast Cancer and Prognostic Impact: Asian Versus Western Populations.

BACKGROUND: The clinicopathological features and prognosis of breast cancer in Asia are different from those in the Western countries. Tumor-infiltrating immune cells can influence the outcome of patients with breast cancer, but they have not been systemically evaluated in Asian patients with breast cancer. METHODS: We compared the immune score, composition, and prognostic impact of infiltrating immune cells between Asian and Western patients with breast cancer by analyzing gene expression profiles from eight Gene Expression Omnibus data sets and The Cancer Genome Atlas data set. The Estimation of Stromal and Immune Cells in Malignant Tumours Using Expression Data (ESTIMATE) and Cell Type Identification by Estimating Relative Subsets of Known RNA Transcripts (CIBERSORT) algorithms were used to determine the immune score and composition of tumor-infiltrating immune cells, respectively. FINDINGS: This study included 462 Asian patients and 2,186 Western patients. Tumors of Asian patients had significantly higher immune score, particularly in the luminal B and HER2-enriched subtypes. High immune score was associated with favorable prognosis in both Asian and Western patients, and Asian race with a high ESTIMATE immune score provided additional power to predict longer disease-free survival. Activated CD4 T cells and M2 macrophages were the most strongly associated with survival in both Asian and Western patients. INTERPRETATION: Our study highlights the difference in tumor immune microenvironments between Asian and Western patients. The higher ESTIMATE immune score, which represents more abundant tumor-infiltrating immune cells, in tumors of Asian patients partly explains their favorable prognosis. IMPLICATIONS FOR PRACTICE: The tumor microenvironment serves as an interface that affects the human body's reaction to cancer cells. Evidence has revealed that tumor-infiltrating immune cells were associated with patient prognosis. This study demonstrated the disparity of tumor microenvironments and their prognostic impact between Asian and Western patients with breast cancer. The differences in immune score partially explained the racial survival differences noted in recent studies. Integrated analysis of tumor cells, tumor microenvironment, and racial effect may significantly improve recurrence risk prediction for patients with stage I-III breast cancer. Because the effect of tumor microenvironment varies across different populations, a model of interaction between immune score and race/ethnicity is recommended in accessing the risk of patients with cancer.

Identification of hyperglycemia-associated microbiota alterations in saliva and gingival sulcus.

Oral microbes are a contributing factor to hyperglycemia by inducing an increase in insulin resistance resulting in uncontrolled blood glucose levels. However, the relationship between the distribution of oral flora and hyperglycemia is still controversial. Combining the power of MALDI-Biotyper with anaerobic bacterial culture, this study explores the correlation between anaerobic bacteria in the oral cavity and blood glucose levels. The results demonstrated that altered blood glucose levels contributed to a varied bacterial distribution in the oral cavity. Specifically, Veillonella spp. and Prevotella spp. were identified in a higher proportion in people with elevated blood glucose levels. Six bacterial species identified in this study (Prevotella melaninogenica, Campylobacter rectus, Streptococcus gordonii, Streptococcus mitis, Streptococcus salivarius, and Veillonella parvula) not only demonstrated a positive association with higher blood glucose levels, but also likely contribute to the development of the condition. The data demonstrated MALDI-TOF MS to be a simpler, faster, and more economical clinical identification tool that provides clarity and depth to the research on blood glucose and oral microbiota.

Using post-column infused internal standard assisted quantitative metabolomics for establishing prediction models for breast cancer detection.

RATIONALE: Breast cancer is one of the most common cancers among women and its associated mortality is on the rise. Metabolomics is a potential strategy for breast cancer detection. The post-column infused internal standard (PCI-IS)-assisted liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been demonstrated as an effective strategy for quantitative metabolomics. In this study, we evaluated the performance of targeted metabolomics with the PCI-IS quantification method to identify women with breast cancer. METHODS: We used metabolite profiling to identify 17 dysregulated metabolites in breast cancer patients. Two LC/MS/MS methods in combination with the PCI-IS strategy were developed to quantify these metabolites in plasma samples. Detection models were built through the analysis of plasma samples from 176 subjects consisting of healthy volunteers and breast cancer patients. RESULTS: Three isotope standards were selected as the PCI-ISs for the metabolites. The accuracy was within 82.8-114.16%, except for citric acid and lactic acid at high concentration levels. The repeatability and intermediate precision were all lower than 15% relative standard deviation. We have identified several metabolites that indicate the presence of breast cancer. The area under the receiver operating characteristics (AUROC) curve, sensitivity and specificity of the linear combinations of metabolite concentrations and age with the highest AUROC were 0.940 (0.889-0.992), 88.4% and 94.2% for pre-menopausal woman, respectively, and 0.828 (0.734-0.922), 73.5% and 85.1% for post-menopausal women, respectively. CONCLUSIONS: The targeted metabolomics with PCI-IS quantification method successfully established prediction models for breast cancer detection. Further study is essential to validate these proposed markers.

A 2-Phase Merge Filter Approach to Computer-Aided Detection of Breast Tumors on 3-Dimensional Ultrasound Imaging.

OBJECTIVES: The role of image analysis in 3-dimensional (3D) automated breast ultrasound (ABUS) images is increasingly important because of its widespread use as a screening tool in whole-breast examinations. However, reviewing a large number of images acquired from ABUS is time-consuming and sometimes error prone. The aim of this study, therefore, was to develop an efficient computer-aided detection (CADe) algorithm to assist the review process. METHODS: The proposed CADe algorithm consisted of 4 major steps. First, initial tumor candidates were formed by extracting and merging hypoechoic square cells on 2-dimensional (2D) transverse images. Second, a feature-based classifier was then constructed using 2D features to filter out nontumor candidates. Third, the remaining 2D candidates were merged longitudinally into 3D masses. Finally, a 3D feature-based classifier was used to further filter out nontumor masses to obtain the final detected masses. The proposed method was validated with 176 passes of breast images acquired by an Acuson S2000 automated breast volume scanner (Siemens Medical Solutions USA, Inc., Malvern, PA), including 44 normal passes and 132 abnormal passes containing 162 proven lesions (79 benign and 83 malignant). RESULTS: The proposed CADe system could achieve overall sensitivity of 100% and 90% with 6.71 and 5.14 false-positives (FPs) per pass, respectively. Our results also showed that the average number of FPs per normal pass (7.16) was more than the number of FPs per abnormal pass (6.56) at 100% sensitivity. CONCLUSIONS: The proposed CADe system has a great potential for becoming a good companion tool with ABUS imaging by ensuring high sensitivity with a relatively small number of FPs.

Basics and applications of tumor-derived extracellular vesicles.

Extracellular vesicle (EV)-mediated intercellular communication acts as a critical culprit in cancer development. The selective packaging of oncogenic molecules renders tumor-derived EVs capable of altering the tumor microenvironment and thereby modulating cancer developments that may contribute to drug resistance and cancer recurrence. Moreover, the molecular and functional characteristics of cancer through its development and posttreatment evolve over time. Tumor-derived EVs are profoundly involved in this process and can, therefore, provide valuable real-time information to reflect dynamic changes occurring within the body. Because they bear unique molecular profiles or signatures, tumor-derived EVs have been highlighted as valuable diagnostic and predictive biomarkers as well as novel therapeutic targets. In addition, the use of an advanced EV-based drug delivery system for cancer therapeutics has recently been emphasized in both basic and clinical studies. In this review, we highlight comprehensive aspects of tumor-derived EVs in oncogenic processes and their potential clinical applications.

Proteomic investigating the cooperative lethal effect of EGFR and MDM2 inhibitors on ovarian carcinoma.

With the concept of precision medicine, combining multiple molecular-targeting therapies has brought new approaches to current cancer treatments. Malfunction of the tumor suppressor protein, p53 is a universal hallmark in human cancers. Under normal conditions, p53 is degraded through an ubiquitin-proteosome pathway regulated by its negative regulator, MDM2. In contrast, cellular stress such as DNA damage will activate p53 to carry out DNA repair, cell cycle arrest, and apoptosis. In this study, we focused on ovarian carcinoma with high EGFR and MDM2 overexpression rate. We assessed the effects of combined inhibition by MDM2 (JNJ-26854165) and EGFR (gefitinib) inhibitors on various ovarian cell lines to determine the importance of these two molecular targets on cell proliferation. We then used a proteomic strategy to investigate the relationship between MDM2 and EGFR inhibition to explore the underlying mechanisms of how their combined signaling blockades work together to exert cooperative inhibition. Our results demonstrated that all four cell lines were sensitive to both individual and combined, MDM2 and EGFR inhibition. The proteomic analysis also showed that gefitinib/JNJ-treated CAOV3 cells exhibited downregulation of proteins involved in nucleotide biosynthesis such as nucleoside diphosphate kinase B (NME2). In conclusion, our study showed that the combined treatment with JNJ and gefitinib exerted synergistic inhibition on cell proliferation, thereby suggesting the potential application of combining MDM2 inhibitors with EGFR inhibitors for enhancing efficacy in ovarian cancer treatment.

Locoregional Recurrence Risk for Postmastectomy Breast Cancer Patients With T1-2 and One to Three Positive Lymph Nodes Receiving Modern Systemic Treatment Without Radiotherapy.

BACKGROUND: Administering postmastectomy radiotherapy (PMRT) to patients with T1-2 breast cancer and one to three positive axillary lymph nodes (ALNs) is controversial. The current study assessed the association of clinicopathologic features and molecular subclassification with locoregional recurrence (LRR) in patients who did not receive PMRT. METHODS: Between January 2004 and December 2008, 293 patients with T1-2 breast cancer and one to three positive ALNs not receiving PMRT were analyzed. Most of the patients received an anthracycline- or taxane-based regimen or both. The patients were divided according to the four molecular subtypes as follows: luminal A/B, luminal human epidermal growth factor receptor 2 (HER2), HER2, and triple-negative breast cancer. Overall survival (OS) and LRR were calculated using the Kaplan-Meier method, and the clinicopathologic prognostic factors were compared using log-rank tests and the Cox regression model. RESULTS: After a median follow-up period of 82.8 months, the 10-year LRR and OS were respectively 10 %, and 88.9 %. The patients with triple-negative breast cancer had a higher 5-year LRR rate (10.6 %) than those without this disease (4.2 %) (p = 0.05). Multivariate analysis showed that young age (≤40 years), tumor larger than 3 cm, and the presence of extensive intraductal components were significant risk factors for LRR. The 5-year LRR was 3.1 % for the patients without the aforementioned risk factors, 7.9 % for those with one risk factor, and 25 % for those with two or more risk factors (p < 0.001). CONCLUSIONS: Administering modern systemic therapy to early breast cancer patients not receiving PMRT reduced the LRR rate. Younger patients, those with a tumor larger than 3 cm, and those with extensive intraductal components might benefit from PMRT.

The association of infrared imaging findings of the breast with prognosis in breast cancer patients: an observational cohort study.

BACKGROUND: To evaluate whether infrared (IR) imaging findings are associated with prognosis in patients with invasive breast carcinomas. METHODS: This study was approved by the institutional review board of the research ethics committee of our hospital, and all participants gave written informed consent. From March 2005 to June 2007, we enrolled 143 patients with invasive breast cancer that underwent preoperative IR imaging. We used five IR signs to interpret breast IR imaging. Cox proportional hazards model was used to evaluate the effect of IR signs on long-term mortality. RESULTS: During a median follow-up of 2451 days (6.7 years), 31 patients died. Based on the Cox Proportional Hazards Model, IR1 sign (the temperature of cancer site minus that of the contralateral mirror imaging site) was positively associated with mortality in the univariate analysis (overall mortality hazard ratio [HR], 2.29; p = 0.03; disease-specific mortality HR, 2.57; p = 0.04) as well as the multivariate analysis after controlling for clinicopathological factors (overall mortality HR, 3.85; p = 0.01; disease-specific mortality HR, 3.91, p = 0.02). In patients with clinical stage I and II disease, IR1 was also positively associated with mortality (overall mortality HR, 3.76; p = 0.03; disease-specific mortality HR, 4.59; p = 0.03). Among patients with node-negative disease, IR1 and IR5 (asymmetrical thermographic pattern) were associated with mortality (p = 0.04 for both IR1 and IR5, chi-squared test). CONCLUSION: Breast IR findings are associated with mortality in patients with invasive breast carcinomas. The association remained in patients with node-negative disease. TRIAL REGISTRATION: NCT00166998 .

Loss of corepressor PER2 under hypoxia up-regulates OCT1-mediated EMT gene expression and enhances tumor malignancy.

The circadian clock gene Period2 (PER2) has been suggested to be a tumor suppressor. However, detailed mechanistic evidence has not been provided to support this hypothesis. We found that loss of PER2 enhanced invasion and activated expression of epithelial-mesenchymal transition (EMT) genes including TWIST1, SLUG, and SNAIL. This finding was corroborated by clinical observation that PER2 down-regulation was associated with poor prognosis in breast cancer patients. We further demonstrated that PER2 served as a transcriptional corepressor, which recruited polycomb proteins EZH2 and SUZ12 as well as HDAC2 to octamer transcription factor 1 (OCT1) (POU2F1) binding sites of the TWIST1 and SLUG promoters to repress expression of these EMT genes. Hypoxia, a condition commonly observed in tumors, caused PER2 degradation and disrupted the PER2 repressor complex, leading to activation of EMT gene expression. This result was further supported by clinical data showing a significant negative correlation between hypoxia and PER2. Thus, our findings clearly demonstrate the tumor suppression function of PER2 and elucidate a pathway by which hypoxia promotes EMT via degradation of PER2.