Thermally boosted interstitial high-dose-rate brachytherapy in high-risk early-stage breast cancer conserving therapy - large cohort long-term results

Background

Early-stage high-risk breast cancer (BC) is standardly treated with breast-conserving therapy (BCT), combined with systemic therapy and radiotherapy (RT) ± tumor bed boost, e.g., with interstitial high-dose-rate brachytherapy (HDR-BT). To improve local recurrence rate (LRR), BT radiosensitization (thermal boost, TB) with interstitial microwave hyperthermia (MWHT) may be an option. The paper aims to report a retrospective single-institutional study on 5- and 10-year local control (LC), distant metastasis-free survival (DMFS), disease-free survival (DFS), overall survival (OS), cosmetic outcome (CO), and late toxicity (fibrosis, fat necrosis) after thermally enhanced HDR-BT boost to the BC tumor bed.

Materials and methods

In 2006-2018, 557 early-stage (I-IIIA) high-risk BC patients were treated with BCT. If indicated, they were administered systemic therapy, then referred for 40.0-50.0 Gy whole breast irradiation (WBI) and 10 Gy interstitial HDR-BT boost (group A). Eligible patients had a single MWHT session preceding BT (group B). Based on present risk factors (RF), medium-risk (1-2 RF) and high-risk subgroups (≥ 3 RF) were formed. Patients were standardly checked, and control mammography (MMG) was performed yearly. Breast cosmesis (Harvard scale) and fibrosis were recorded. LC, DMFS, DFS, and OS were statistically analyzed.

Results

Out of 557 patients aged 57 years (26-84), 364 (63.4%) had interstitial HDR-BT boost (group A), and 193 (34.6%) were preheated with MWHT (group B). Patients in group B had a higher clinical stage and had more RFs. The median follow-up was 65.9. Estimated 5-year and 10-year LC resulted in 98.5% and 97.5%, respectively. There was no difference in LC, DMFS, DFS, and OS between groups A and B and between extracted high-risk subgroups A and B. Five- and ten-year OS probability was 95.4% and 88.0%, respectively, with no difference between groups A and B. Harvard criteria-based CO assessment revealed good/excellent cosmesis in 74.9-79.1%. Tumor bed hardening was present in 40.1-42.2%. Asymptomatic fat necrosis-related macrocalcifications were detected in 15.6%, more frequently in group B (p = 0.016).

Conclusions

Thermally boosted or not, HDR-BT was locally highly effective as part of combined treatment. Five- and ten-year LC, DMFS, DFS, and OS were high and equally distributed between the groups, although TB was prescribed in more advanced one with more RFs. TB did not influence CO and fibrosis. TB added to late toxicity regarding asymptomatic fat necrosis detected on MMG.

Nomogram prediction of the 70-gene signature (MammaPrint) binary and quartile categorized risk using medical history, imaging features and clinicopathological data among Chinese breast cancer patients

BACKGROUND

The 70-gene signature (70-GS, MammaPrint) test has been recommended by the main guidelines to evaluate prognosis and chemotherapy benefit of hormonal receptor positive human epidermal receptor 2 negative (HR + /Her2-) early breast cancer (BC). However, this expensive assay is not always accessible and affordable worldwide. Based on our previous study, we established nomogram models to predict the binary and quartile categorized risk of 70-GS.

METHODS

We retrospectively analyzed a consecutive cohort of 150 female patients with HR + /Her2- BC and eligible 70-GS test. Comparison of 40 parameters including the patients' medical history risk factors, imaging features and clinicopathological characteristics was performed between patients with high risk (N = 62) and low risk (N = 88) of 70-GS test, whereas risk calculations from established models including Clinical Treatment Score Post-5 years (CTS5), Immunohistochemistry 3 (IHC3) and Nottingham Prognostic Index (NPI) were also compared between high vs low binary risk of 70-GS and among ultra-high (N = 12), high (N = 50), low (N = 65) and ultra-low (N = 23) quartile categorized risk of 70-GS. The data of 150 patients were randomly split by 4:1 ratio with training set of 120 patients and testing set 30 patients. Univariate analyses and multivariate logistic regression were performed to establish the two nomogram models to predict the the binary and quartile categorized risk of 70-GS.

RESULTS

Compared to 70-GS low-risk patients, the high-risk patients had significantly less cardiovascular co-morbidity (p = 0.034), more grade 3 BC (p = 0.006), lower progesterone receptor (PR) positive percentage (p = 0.007), more Ki67 high BC (≥ 20%, p < 0.001) and no significant differences in all the imaging parameters of ultrasound and mammogram. The IHC3 risk and the NPI calculated score significantly correlated with both the binary and quartile categorized 70-GS risk classifications (both p < 0.001). The area under curve (AUC) of receiver-operating curve (ROC) of nomogram for binary risk prediction were 0.826 (C-index 0.903, 0.799-1.000) for training and 0.737 (C-index 0.785, 0.700-0.870) for validation dataset respectively. The AUC of ROC of nomogram for quartile risk prediction was 0.870 (C-index 0.854, 0.746-0.962) for training and 0.592 (C-index 0.769, 0.703-0.835) for testing set. The prediction accuracy of the nomogram for quartile categorized risk groups were 55.0% (likelihood ratio tests, p < 0.001) and 53.3% (p = 0.04) for training and validation, which more than double the baseline probability of 25%.

CONCLUSIONS

To our knowledge, we are the first to establish easy-to-use nomograms to predict the individualized binary (high vs low) and the quartile categorized (ultra-high, high, low and ultra-low) risk classification of 70-GS test with fair performance, which might provide information for treatment choice for those who have no access to the 70-GS testing.

Exploring the Versatility of Exosomes: A Review on Isolation, Characterization, Detection Methods, and Diverse Applications

Extracellular vesicles (EVs) are crucial mediators of intercellular communication and can be classified based on their physical properties, biomolecular structure, and origin. Among EVs, exosomes have garnered significant attention due to their potential as therapeutic and diagnostic tools. Exosomes are released via fusion of multivesicular bodies on plasma membranes and can be isolated from various biofluids using methods such as differential ultracentrifugation, immune affinity capture, ultrafiltration, and size exclusion chromatography. Herein, an overview of different techniques for exosome characterization and isolation, as well as the diverse applications of exosome detection, including their potential use in drug delivery and disease diagnosis, is provided. Additionally, we discuss the emerging field of exosome detection by sensors, which offers an up-and-coming avenue for point-of-care diagnostic tools development. Overall, this review aims to provide a exhaustive and up-to-date summary of the current state of exosome research.

Potential roles of the exosome/microRNA axis in breast cancer

Cancer is one of the most common diseases in the world, and various genetic and environmental factors play a key role in its development. Breast cancer is one of the most common and deadly cancers in women. Exosomes are extracellular vesicles (EVs) with an average size of about 100 nm that contain lipids, proteins, microRNAs (miRNAs), and genetic factors and play a significant role in cell signaling, communication, tumorigenesis, and drug resistance. miRNAs are RNAs with about 22 nucleotides, which are synthesized by RNA polymerase and are involved in regulating gene expression, as well as the prevention or progression of cancer. Many studies have indicated the connection between miRNAs and exosomes. According to their findings, it seems that circulating exosomal miRNAs have not been well evaluated as biomarkers for breast cancer diagnosis or monitoring. Therefore, given the importance of miRNAs in exosomes, the goal of the present study was to clarify the relationship between miRNAs in exosomes and the role they play as biomarkers in breast cancer.

Exosomal microRNAs as novel diagnostic biomarkers in breast cancer: A systematic evaluation and meta-analysis

Circulating tumor-derived exosomal microRNAs (miRNAs) play a key role in the development of cancer. We aimed to assess the diagnostic value of circulating exosomal miRNAs in breast cancer (BC). A computer search was conducted for clinical studies on exosomal miRNA diagnosis of breast cancer published in Wanfang, CNKI, China Biology Medicine disc, VIP, Web of Science, Cochrane Library, PubMed, and Embase built up to August 16, 2022. True/false positive (TP/FP) and true/false negative (TN/FN) rates were extracted from each eligible study to obtain pooled sensitivities, specificities, positive/negative likelihood ratios (PLR/NLR), diagnostic odds ratio (DOR), and their 95% confidence intervals (95% CI). The meta-analysis included 7 articles including 348 Asian patients and 260 controls. All miRNAs were quantified using qRT-PCR assays. The sensitivity and specificity of the combination were 0.67 (95% CI = 0.64-0.71) and 0.81 (95% CI = 0.77-0.86), respectively. The combined DOR was 10.2 (95% CI = 6.00-16.74). The combined AUC(area under the subject operating characteristic curve) was 0.83 (0.91-0.96). In conclusion, exosomal-derived miRNA can be a good indicator to improve the diagnosis of breast cancer.

miRNAs in the Box: Potential Diagnostic Role for Extracellular Vesicle-Packaged miRNA-27a and miRNA-128 in Breast Cancer

Circulating extracellular vesicle (EV)-derived microRNAs (miRNAs) are now considered the next generation of cancer "theranostic" tools, with strong clinical relevance. Although their potential in breast cancer diagnosis has been widely reported, further studies are still required to address this challenging issue. The present study examined the expression profiles of EV-packaged miRNAs to identify novel miRNA signatures in breast cancer and verified their diagnostic accuracy. Circulating EVs were isolated from healthy controls and breast cancer patients and characterized following the MISEV 2018 guidelines. RNA-sequencing and real-time PCR showed that miRNA-27a and miRNA-128 were significantly down-regulated in patient-derived EVs compared to controls in screening and validation cohorts. Bioinformatics analyses of miRNA-target genes indicated several enriched biological processes/pathways related to breast cancer. Receiver operating characteristic (ROC) curves highlighted the ability of these EV-miRNAs to distinguish breast cancer patients from non-cancer controls. According to other reports, the levels of EV-miRNA-27a and EV-miRNA-128 are not associated with their circulating ones. Finally, evidence from the studies included in our systematic review underscores how the expression of these miRNAs in biofluids is still underinvestigated. Our findings unraveled the role of serum EV-derived miRNA-27a and miRNA-128 in breast cancer, encouraging further investigation of these two miRNAs within EVs towards improved breast cancer detection.

Circulating exosomal miRNAs as a promising diagnostic biomarker in cancer

Cancer belongs to multifactorial diseases characterized by uncontrolled growth and proliferation of abnormal cells. Breast cancer, non-small cell lung cancer, and colorectal cancer are the most frequently diagnosed malignancies with a high mortality rate. These carcinomas typically contain multiple genetically distinct subpopulations of tumor cells leading to tumor heterogeneity, which promotes the aggressiveness of the disease. Early diagnosis is necessary to increase patient progression-free survival. Particularly, miRNAs present in exosomes derived from tumors represent potential biomarkers suitable for early cancer diagnosis. Identification of miRNAs by liquid biopsy enables a personalized approach with the subsequent better clinical management of patients. This review article highlights the potential of circulating exosomal miRNAs in early breast, non-small cell lung, and colorectal cancer diagnosis.

Secoisolariciresinol diglucoside regulates estrogen receptor expression to ameliorate OVX-induced osteoporosis

OBJECTIVE

Secoisolariciresinol diglucoside (SDG) is a phytoestrogen that has been reported to improve postmenopausal osteoporosis (PMOP) caused by estrogen deficiency. In our work, we aimed to investigate the mechanism of SDG in regulating the expressions of ERs on PMOP model rats.

METHODS

Ovariectomization (OVX) was used to establish PMOP model in rats. The experiment was allocated to Sham, OVX, SDG and raloxifene (RLX) groups. After 12-week treatment, micro-CT was used to detect the transverse section of bone. Hematoxylin and Eosin staining and Safranine O-Fast Green staining were supplied to detect the femur pathological morphology of rats. Estradiol (E2), interleukin-6 (IL-6), bone formation and bone catabolism indexes in serum were detected using ELISA. Alkaline phosphatase (ALP) staining was used to detect the osteogenic ability of chondrocytes. Immunohistochemistry and Western blot were applied to detect the protein expressions of estrogen receptors (ERs) in the femur of rats.

RESULTS

Compared with the OVX group, micro-CT results showed SDG could lessen the injury of bone and improve femoral parameters, including bone mineral content (BMC) and bone mineral density (BMD). Pathological results showed SDG could reduce pathological injury of femur in OVX rats. Meanwhile, SDG decreased the level of IL-6 and regulated bone formation and bone catabolism indexes. Besides, SDG increased the level of E2 and conversed OVX-induced decreased the expression of ERα and ERβ.

CONCLUSION

The treatment elicited by SDG in OVX rats was due to the reduction of injury and inflammation and improvement of bone formation index, via regulating the expression of E2 and ERs.

Dual amplified electrochemical sensing coupling of ternary hybridization-based exosomal microRNA recognition and perchlorate-assisted electrocatalytic cycle

Exosomal microRNA (miRNA) are important biomarkers for liquid biopsy, and display clinical molecular signatures for cancer diagnosis. Although advanced detection methods have been established to detect exosomal miRNAs, they are faced with certain challenges. Therefore, we aimed to establish a dual amplification-based electrochemical method for detecting exosomal miRNA. This method combined a two-hairpins-based ternary hybridization structure (thTHS)-initiated single-stranded DNA (ssDNA) amplification reaction (ssDAR) and sodium perchlorate (NaClO4)-assisted electrocatalytic cycle. Two DNA hairpins were designed to hybridize with target miRNA, forming thTHS. Next, ssDAR was triggered by thTHS to produce long ssDNA on magnetic beads. The long ssDNA, complementary to the signal probes, was subsequently released onto a methylene blue (MB)-labeled double-stranded DNA-modified electrode for strand displacement reaction. This led to a quantitative change in MB and a change in electrocatalytic reduction current from the electrocatalytic cycle of MB-ferricyanide. An amplified electrocatalytic reduction current was produced by adding NaClO4 to the electrocatalytic system, which substantially improved the signal response range and detection sensitivity. Ultimately, exosomal miRNA detection was achieved by recording changes in the electrocatalytic reduction current before and after miRNA addition. This electrochemical method exhibited a sensitive concentration response with a detection limit of 45 aM and selective miRNA recognition, and successfully used to detect exosomal miRNA derived from cells and serum. Additionally, this method exhibited better discrimination ability between patients with breast cancer (BC) and those people without BC (patients with benign breast disease and healthy people), providing a promising strategy for detecting and monitoring cancer biomarkers.

Tailoring Potential Natural Compounds for the Treatment of Luminal Breast Cancer

Breast cancer (BC) is the most diagnosed cancer worldwide, mainly affecting the epithelial cells from the mammary glands. When it expresses the estrogen receptor (ER), the tumor is called luminal BC, which is eligible for endocrine therapy with hormone signaling blockade. Hormone therapy is essential for the survival of patients, but therapeutic resistance has been shown to be worrying, significantly compromising the prognosis. In this context, the need to explore new compounds emerges, especially compounds of plant origin, since they are biologically active and particularly promising. Natural products are being continuously screened for treating cancer due to their chemical diversity, reduced toxicity, lower side effects, and low price. This review summarizes natural compounds for the treatment of luminal BC, emphasizing the activities of these compounds in ER-positive cells. Moreover, their potential as an alternative to endocrine resistance is explored, opening new opportunities for the design of optimized therapies.

Role of exosomes in prostate cancer bone metastasis

Bone is a preferred metastatic site of prostate cancer (PCa), and most patients with PCa metastases develop osteogenic bone metastasis, which manifests as disturbed bone structure and poor bone quality. However, the underlying mechanisms of PCa bone metastasis remain unclear. In recent years, increasing evidence has implicated extracellular vesicles, especially exosomes, in PCa bone metastasis. Exosomes are 30-150 nm in diameter, enclosing a cargo of biomolecules, such as DNA, RNA, and proteins. Exosomes play a functional role in intercellular communication, modulate the functions of recipient cells, and potentially modulate bone microenvironment changes, thereby influencing the development of PCa bone metastasis. This review summarizes the involvement of exosomes in the imbalance between bone resorption and formation, and establishing a pre-metastatic niche in bone marrow, as well as potential clinical applications of exosomes in therapeutic strategies for treating patients with advanced PCa with bone metastasis.

CADM1 impairs the effect of miR-1246 on promoting cell cycle progression in chemo-resistant leukemia cells

The interruption of normal cell cycle execution acts as an important part to the development of leukemia. It was reported that microRNAs (miRNAs) were closely related to tumorigenesis and progression, and their aberrant expression had been demonstrated to play a crucial role in numerous types of cancer. Our previous study showed that miR-1246 was preferentially overexpressed in chemo-resistant leukemia cell lines, and participated in process of cell cycle progression and multidrug resistant regulation. However, the underlying mechanism remains unclear. In present study, bioinformatics prediction and dual luciferase reporter assay indicated that CADM1 was a direct target of miR-1246. Evidently decreased expression of CADM1 was observed in relapsed primary leukemia patients and chemo-resistant cell lines. Our results furtherly proved that inhibition of miR-1246 could significantly enhance drug sensitivity to Adriamycin (ADM), induce cell cycle arrest at G0/G1 phase, promote cell apoptosis, and relieve its suppression on CADM1 in K562/ADM and HL-60/RS cells. Interference with CADM1 could reduce the increased drug sensitivity induced by miR-1246 inhibition, and notably restore drug resistance by promoting cell cycle progression and cell survival via regulating CDKs/Cyclins complexes in chemo-resistant leukemia cells. Above all, our results demonstrated that CADM1 attenuated the role of miR-1246 in promoting cell cycle progression and cell survival, thus influencing multidrug resistance within chemo-resistant leukemia cells via CDKs/Cyclins. Higher expression of miR-1246 and lower expression of CADM1 might be risk factors for leukemia.

Trends in research of exosomes associated with breast cancer over the past decade: a scientometric analysis

Introduction

Breast cancer remains a significant global health challenge, accounting for 2.3 million new cases in 2020 and ranking as the most prevalent cancer by incidence and the fourth in cancer-related mortality worldwide. In China, breast cancer also rapidly increases incidence and burden. The research of exosomes in breast cancer has attracted more and more attention and has a rapid development. Recognizing the pivotal role of exosomes in breast cancer research, we have undertaken a comprehensive scientometric analysis of pertinent scholarly articles published over the past decade to elucidate the current research landscape for researchers.

Methods

In this study, we gathered all pertinent publications from the Web of Science. Biblioshiny (a web interface for Bibliometrix), VOSviewer software, and CiteSpace software were used to analyze the information on publications, including global trends, countries, institutions, journals, authors, keywords, and citations.

Results

A total of 1,239 articles and 625 review articles were retrieved. The annual global publication output has an increased trend in recent decades overall. China contributed the most articles. The publications of the USA had the most total link strength. Nanjing Medical University had the most total link strength. The most relevant source was the International Journal of Molecular Sciences. Tang JH contributed the most articles and had the highest H-index, G-index, and total link strength. The most cited document was "Tumor exosome integrins determine organotropic metastasis", with 2730 citations. The basic themes included "exosomes", "expression", "cells", "identification", "biomarkers", and "serum". The keyword "membrane vesicle" had the strongest bursts. The keywords "target", "biology", "suppressor cell", "molecular mechanism", "tumor progression", "inhibitor", and "model" appeared as prominent focal points in current research and active areas of exploration.

Conclusion

Over the past decade, exosome research in breast cancer has undergone a discernible evolution, shifting from broader investigations of exosome roles to focused exploration of specific pathways relevant to breast cancer. Notably, the emphasis has extended to the clinical application of exosomes as biomarkers and potential therapeutic agents in breast cancer treatment.

Discovery of lipid profiles in plasma-derived extracellular vesicles as biomarkers for breast cancer diagnosis

Lipids are a major component of extracellular vesicles; however, their significance in tumorigenesis and progression has not been well elucidated. As we previously found that lipid profiles drastically changed in breast tumors upon progression, we hypothesized that lipid profiles of plasma-derived extracellular vesicles could be utilized as breast cancer biomarkers. Here, we adopted modified sucrose cushion ultracentrifugation to isolate plasma-derived extracellular vesicles from breast cancer (n = 105), benign (n = 11), and healthy individuals (n = 43) in two independent cohorts (n = 126 and n = 33) and conducted targeted lipidomic analysis. We established a breast cancer diagnostic model comprising three lipids that showed favorable performance with the area under the receiver operating characteristic curve of 0.759, 0.743, and 0.804 in the training, internal validation, and external test sets, respectively. Moreover, we identified several lipids that could effectively discriminate breast cancer progression and subtypes: phosphatidylethanolamines and phosphatidylserines were relatively higher in Stage III, whereas phosphatidylcholines and sphingomyelins were higher in Stage IV; phosphatidylcholines and ceramides were correspondingly concentrated in HER2-positive patients, while lysophosphatidylcholines and polyunsaturated triglycerides were concentrated in the triple-negative breast cancer subtype. Lipid profiling of plasma-derived extracellular vesicles is a non-invasive and promising approach for diagnosing, staging, and subtyping breast cancer.

Recent insights into the nutritional immunomodulation of cancer-related microRNAs

Cancer is the most common cause of death worldwide, following cardiovascular diseases. Cancer is a multifactorial disease and many reasons such as physical, chemical, biological, and lifestyle-related factors. Nutrition, which is one of the various factors that play a role in the prevention, development, and treatment of many types of cancer, affects the immune system, which is characterized by disproportionate pro-inflammatory signaling in cancer. Studies investigating the molecular mechanisms of this effect have shown that foods rich in bioactive compounds, such as green tea, olive oil, turmeric, and soybean play a significant role in positively changing the expression of miRNAs involved in the regulation of genes associated with oncogenic/tumor-suppressing pathways. In addition to these foods, some diet models may change the expression of specific cancer-related miRNAs in different ways. While Mediterranean diet has been associated with anticancer effects, a high-fat diet, and a methyl-restricted diet are considered to have negative effects. This review aims to discuss the effects of specific foods called "immune foods," diet models, and bioactive components on cancer by changing the expression of miRNAs in the prevention and treatment of cancer.

Investigating Factors Associated with Postmastectomy Emergency Department Visits: A Population-Based Analysis

BACKGROUND

In 2016, a multi-pronged pathway was implemented across 13 hospitals to improve the mastectomy perioperative care experience with one objective being to safely allow same day surgery mastectomy. While the pathway successfully increased same day mastectomy rates from 1.7 to 73.0%, the rate of postoperative emergency department (ED) visits remained high at > 20%, despite focused interventions to enhance perioperative support.

AIM

To investigate potential factors associated with high postoperative ED visits following mastectomies in Alberta, Canada.

METHODS

Data was collected using the Discharge Abstract Database and the National Ambulatory Care Reporting System database. Eligible patients included all women over 18 years old who underwent a mastectomy province-wide between 2004 and 2020. Patient demographics were collected. Primary outcome of interest was ED visit within 30 days of mastectomy. Univariate and multivariable analyses were performed to identify independent predictors for post-operative ED visits.

RESULTS

A total of 19,974 patients had mastectomy during the study period, of which 4590 (23%) had an ED visit within 30 days of surgery. Independent factors associated with ED visits were increasing age, overnight stay mastectomy, reconstruction, certain comorbidities, and living rurally.

CONCLUSIONS

Post-operative ED visits remain high despite initiating a province-wide surgical pathway in 2016 which emphasizes patient education and improved perioperative care and supports. Currently, the majority of ED visits are manageable in non-emergent settings. Patient populations at higher risk for ED visits groups may benefit from additional targeted support and resources to reduce unplanned ED visits.

The role of non-coding RNAs in extracellular vesicles in breast cancer and their diagnostic implications

Breast Cancer (BC) is the most common form of cancer worldwide, responsible for 25% of cancers in women. Whilst treatment is effective and often curative in early BC, metastatic disease is incurable, highlighting the need for early detection. Currently, early detection relies on invasive procedures, however recent studies have shown extracellular vesicles (EVs) obtained from liquid biopsies may have clinical utility. EVs transport diverse bioactive cargos throughout the body, play major roles in intercellular communication and, importantly, mirror their cell of origin. In cancer cells, EVs alter the behaviour of the tumour microenvironment (TME), forming a bridge of communication between cancerous and non-cancerous cells to alter all aspects of cancer progression, including the formation of a pre-metastatic niche. Through gene regulatory frameworks, non-coding RNAs (ncRNAs) modulate vital molecular and cellular processes and can act as both tumour suppressors and oncogenic drivers in various cancer types. EVs transport and protect ncRNAs, facilitating their use clinically as liquid biopsies for early BC detection. This review summarises current research surrounding ncRNAs and EVs within BC, focusing on their roles in cancer progression through bi-directional communication with the microenvironment and their diagnostic implications. The role of EV ncRNAs in breast cancer. A representation of the different EV ncRNAs involved in tumourigenic processes in breast cancer. Pro-tumourigenic ncRNAs displayed in green and ncRNAs which inhibit oncogenic processes are shown in red.

Engineered exosomes as drug and RNA co-delivery system: new hope for enhanced therapeutics?

Chemotherapy often faces some obstacles such as low targeting effects and drug resistance, which introduce the low therapeutic efficiency and strong side effects. Recent advances in nanotechnology allows the use of novel nanosystems for targeted drug delivery, although the chemically synthesized nanomaterials always show unexpected low biocompability. The emergence of exosome research has offered a better understanding of disease treatment and created novel opportunities for developing effective drug delivery systems with high biocompability. Moreover, RNA interference has emerged as a promising strategy for disease treatments by selectively knocking down or over-expressing specific genes, which allows new possibilities to directly control cell signaling events or drug resistance. Recently, more and more interests have been paid to develop optimal delivery nanosystems with high efficiency and high biocompability for drug and functional RNA co-delivery to achieve enhanced chemotherapy. In light of the challenges for developing drug and RNA co-delivery system, exosomes have been found to show very attractive prospects. This review aims to explore current technologies and challenges in the use of exosomes as drug and RNA co-delivery system with a focus on the emerging trends and issues associated with their further applications, which may contribute to the accelerated developments of exosome-based theraputics.

Neoadjuvant and Adjuvant Treatments for Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma: The Current Status of Pancreatic Ductal Adenocarcinoma Treatment in Japan

Resection is the only curative treatment for pancreatic ductal adenocarcinoma (PDAC). Although the outcome of technically resectable PDAC has improved with advances in surgery and adjuvant therapy, the 5-year survival rate remains low at 20% to 40%. More effective therapy is needed. Almost 15 years ago, the National Comprehensive Cancer Network guidelines proposed a resectability classification of PDAC based on preoperative imaging. Since then, treatment strategies for PDAC have been devised based on resectability. The standard of care for resectable PDAC is adjuvant chemotherapy after R0 resection, as shown by the results of pivotal clinical trials. With regard to neoadjuvant treatment, several recent clinical trials comparing neoadjuvant treatment with upfront resection have been conducted on resectable PDAC and borderline resectable PDAC, and the benefits and efficacy of neoadjuvant treatment for pancreatic cancer has become clearer. The significance of neoadjuvant treatment for resectable PDAC remains controversial, but in borderline resectable PDAC the efficacy of neoadjuvant treatment has been further recognised, although the standard of care has not yet been established. Several promising clinical trials for PDAC are ongoing. This review presents previous and ongoing trials of perioperative treatment for resectable and borderline resectable PDAC, focusing on the difference between Asian and Western countries.

Communicator Extraordinaire: Extracellular Vesicles in the Tumor Microenvironment Are Essential Local and Long-Distance Mediators of Cancer Metastasis

Human tumors are increasingly being described as a complex "ecosystem", that includes many different cell types, secreted growth factors, extracellular matrix (ECM) components, and microvessels, that altogether create the tumor microenvironment (TME). Within the TME, epithelial cancer cells control the function of surrounding stromal cells and the non-cellular ECM components in an intricate orchestra of signaling networks specifically designed for cancer cells to exploit surrounding cells for their own benefit. Tumor-derived extracellular vesicles (EVs) released into the tumor microenvironment are essential mediators in the reprogramming of surrounding stromal cells, which include cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), tumor-infiltrating lymphocytes (TILs), and tumor endothelial cells (TECs), which are responsible for the promotion of neo-angiogenesis, immune cell evasion, and invasion which are essential for cancer progression. Perhaps most importantly, tumor-derived EVs play critical roles in the metastatic dissemination of tumor cells through their two-fold role in initiating cancer cell invasion and the establishment of the pre-metastatic niche, both of which are vital for tumor cell migration, homing, and colonization at secondary tumor sites. This review discusses extracellular vesicle trafficking within the tumor microenvironment and pre-metastatic niche formation, focusing on the complex role that EVs play in orchestrating cancer-to-stromal cell communication in order to promote the metastatic dissemination of cancer cells.

Identification of exosomal microRNA panel as diagnostic and prognostic biomarker for small cell lung cancer

BACKGROUND

Small cell lung cancer (SCLC) has an exceptionally poor prognosis; as most of the cases are initially diagnosed as extensive disease with hematogenous metastasis. Therefore, the early diagnosis of SCLC is very important and may improve its prognosis.

METHODS

To investigate the feasibility of early diagnosis of SCLC, we examined exosomal microRNAs (miRNAs) present in serum obtained from patients with SCLC. First, exosomes were isolated in serum from patients with SCLC and healthy individuals and were characterized using particle size and protein markers. Additionally, miRNA array was performed to define SCLC-specific exosomal miRNAs. Second, the obtained miRNAs were further validated employing a large cohort. Finally, the ability to diagnose SCLC was estimated by area under the curve (AUC), and intracellular mRNA change patterns were verified through validated miRNAs.

RESULTS

From the miRNA array results, we selected 51-miRNAs based on p-values and top 10 differentially expressed genes, and 25-miRNAs were validated using quantitative reverse transcription-polymerase chain reaction. The 25-miRNAs were further validated employing a large cohort. Among them, 7-miRNAs showed significant differences. Furthermore, 6-miRNAs (miR-3565, miR-3124-5p, miR-200b-3p, miR-6515, miR-3126-3p and miR-9-5p) were up-regulated and 1-miRNA (miR-92b-5p) was down-regulated. The AUC value of each miRNA sets between 0.64 and 0.76, however the combined application of 3-miRNAs (miR-200b-3p, miR-3124-5p and miR-92b-5p) remarkably improved the diagnostic value (AUC = 0.93). Gene ontology analysis revealed that the 3-miRNA panel is linked to various oncogene pathways and nervous system development. When the 3-miRNAs were introduced to cells, the resulting changes in total mRNA expression strongly indicated the presence of lung diseases, including lung cancer. In addition, the 3-miRNA panel was significantly associated with a poorer prognosis, although individual miRNAs have not been validated as prognostic markers.

CONCLUSION

Our study identified SCLC-specific exosomal miRNAs, and the 3-miRNAs panel (miR-200b-3p, miR-3124-5p and miR-92b-5p) may serve as a diagnostic and prognostic marker for SCLC.

The origin of brain malignancies at the blood-brain barrier

Despite improvements in extracranial therapy, survival rate for patients suffering from brain metastases remains very poor. This is coupled with the incidence of brain metastases continuing to rise. In this review, we focus on core contributions of the blood-brain barrier to the origin of brain metastases. We first provide an overview of the structure and function of the blood-brain barrier under physiological conditions. Next, we discuss the emerging idea of a pre-metastatic niche, namely that secreted factors and extracellular vesicles from a primary tumor site are able to travel through the circulation and prime the neurovasculature for metastatic invasion. We then consider the neurotropic mechanisms that circulating tumor cells possess or develop that facilitate disruption of the blood-brain barrier and survival in the brain's parenchyma. Finally, we compare and contrast brain metastases at the blood-brain barrier to the primary brain tumor, glioma, examining the process of vessel co-option that favors the survival and outgrowth of brain malignancies.

Earlier Diagnosis of Pancreatic Cancer: Is It Possible?

Pancreatic ductal adenocarcinoma has a very high mortality rate which has been only minimally improved in the last 30 years. This high mortality is closely related to late diagnosis, which is usually made when the tumor is large and has extensively infiltrated neighboring tissues or distant metastases are already present. This is a paradoxical situation for a tumor that requires nearly 15 years to develop since the first founding mutation. Response to chemotherapy under such late circumstances is poor, resistance is frequent, and prolongation of survival is almost negligible. Early surgery has been, and still is, the only approach with a slightly better outcome. Unfortunately, the relapse percentage after surgery is still very high. In fact, early surgery clearly requires early diagnosis. Despite all the advances in diagnostic methods, the available tools for improving these results are scarce. Serum tumor markers permit a late diagnosis, but their contribution to an improved therapeutic result is very limited. On the other hand, effective screening methods for high-risk populations have not been fully developed as yet. This paper discusses the difficulties of early diagnosis, evaluates whether the available diagnostic tools are adequate, and proposes some simple and not-so-simple measures to improve it.

Utility of the intraflap perfusion procedure for abdominal free flap in unilateral breast reconstruction

BACKGROUND

Heparin prophylaxis for venous thromboembolism can be used in microsurgery. If vein anastomosis is performed before the artery, heparin irrigation into the artery can be performed locally without systematic effect. This study aimed to introduce this "intraflap perfusion procedure" in autologous breast reconstruction.

METHODS

Among the 220 patients with unilateral breast cancer who had received the free abdominal flap, we retrospectively compared those that had undergone the intraflap perfusion procedure (n = 108) and those who did not (n = 112). A 10 mL injection of heparinized physiological saline solution (100 units/mL) was administered into the deep inferior epigastric artery. Intraflap perfusion was performed before, during, and after vein anastomosis, without the vessel clip of the vein. Artery anastomosis was performed without the use of a vein clamp. Further, vein anastomosis was performed tightly to prevent leakage from the vein anastomosis site during artery anastomosis.

RESULTS

The rates of superficial inferior epigastric vein (SIEV) superdrainage (18.5% vs. 42.0%, P < 0.001), and intraoperative flap congestion (0.9% vs. 8.0%, P = 0.01) were significantly lower in patients undergoing this procedure. There were no significant differences regarding other factors (age, BMI, laterality, comorbidities, and other operative details).

CONCLUSIONS

Intraflap perfusion prevented long-term stasis at the venous anastomosis site and capillary level. It could reduce flap congestion. SIEV superdrainage was performed to manage flap congestion, particularly in patients who did not undergo this procedure. Consequently, it can be inferred that this procedure reduces the rate of superdrainage.

Correlation between abdominal visceral volume measured by a simple procedure and bulging at the abdominal free flap donor site for breast reconstruction

BACKGROUND

Breast reconstructions using autologous abdominal tissue result in breasts with a natural shape and consistency. One of the major complications is abdominal bulging. Because of the increased abdominal wall tension, high visceral volume (not visceral fat alone) may increase the occurrence rate of abdominal bulging. A simple procedure involving CT imaging was used to assess this relationship in patients undergoing an abdominal free flap for unilateral breast reconstruction.

METHODS

A total of 278 patients were enrolled in this study. The patients' demographics, the thicknesses of visceral volume were compared (Bulging (+) vs. Bulging (-)). Visceral volume was investigated based on the horizontal thickness, which was measured at the thickest part at the level of the umbilical fossa between both sides under the transverse abdominis muscles.

RESULTS

Bulging (+) consisted of 39 patients (14.0%), whereas Bulging (-) included 239 patients. Patients with Bulging (+) were significantly older, had higher gestational history rate, and had thin rectus abdominis muscle. In terms of visceral volume, the Bulging (+) group had significantly higher horizontal thicknesses (median 233 mm vs. 219 mm, P < 0.001). No significant differences were observed with respect to other factors (age, BMI, history of laparotomy, and operative details). The multivariate logistic regression analysis revealed that the thickness of the rectus abdominis muscle, horizontal visceral volume, and gestational history were independently significant predictors.

CONCLUSIONS

Not only the patients with thin rectus abdominis muscle but also patients with a thick horizontal visceral volume may have a higher risk of abdominal bulging.

Exosomal miRNAs and breast cancer: a complex theranostics interlink with clinical significance

Breast cancer (BC) remains the most challenging global health crisis of the current decade, impacting a large population of females annually. In the field of cancer research, the discovery of extracellular vesicles (EVs), specifically exosomes (a subpopulation of EVs), has marked a significant milestone. In general, exosomes are released from all active cells but tumour cell-derived exosomes (TDXs) have a great impact (TDXs miRNAs, proteins, lipid molecules) on cancer development and progression. TDXs regulate multiple events in breast cancer such as tumour microenvironment remodelling, immune cell suppression, angiogenesis, metastasis (EMT-epithelial mesenchymal transition, organ-specific metastasis), and therapeutic resistance. In BC, early detection is the most challenging event, exosome-based BC screening solved the problem. Exosome-based BC treatment is a sign of the transforming era of liquid biopsy, it is also a promising therapeutic tool for breast cancer. Exosome research goes to closer precision oncology via a single exosome profiling approach. Our hope is that this review will serve as motivation for researchers to explore the field of exosomes and develop an efficient, and affordable theranostics approach for breast cancer.

Aberrant hyper-expression of the RNA binding protein GIGYF2 in endothelial cells modulates vascular aging and function

Vascular endothelial cells (ECs) senescence plays a crucial role in vascular aging that promotes the initiation and progression of cardiovascular disease. The mutation of Grb10-interacting GYF protein 2 (GIGYF2) is strongly associated with the pathogenesis of aging-related diseases, whereas its role in regulating ECs senescence and dysfunction still remains elusive. In this study, we found aberrant hyperexpression of GIGYF2 in senescent human ECs and aortas of old mice. Silencing GIGYF2 in senescent ECs suppressed eNOS-uncoupling, senescence, and endothelial dysfunction. Conversely, in nonsenescent cells, overexpressing GIGYF2 promoted eNOS-uncoupling, cellular senescence, endothelial dysfunction, and activation of the mTORC1-SK61 pathway, which were ablated by rapamycin or antioxidant N-Acetyl-l-cysteine (NAC). Transcriptome analysis revealed that staufen double-stranded RNA binding protein 1 (STAU1) is remarkably downregulated in the GIGYF2-depleted ECs. STAU1 depletion significantly attenuated GIGYF2-induced cellular senescence, dysfunction, and inflammation in young ECs. Furthermore, we disclosed that GIGYF2 acting as an RNA binding protein (RBP) enhances STAU1 mRNA stability, and that the intron region of the late endosomal/lysosomal adaptor MAPK and mTOR activator 4 (LAMTOR4) could bind to STAU1 protein to upregulate LAMTOR4 expression. Immunofluorescence staining showed that GIGYF2 overexpression promoted the translocation of mTORC1 to lysosome. In the mice model, GIGYF2flox/flox Cdh-Cre+ mice protected aged mice from aging-associated vascular endothelium-dependent relaxation and arterial stiffness. Our work discloses that GIGYF2 serving as an RBP enhances the mRNA stability of STAU1 that upregulates LAMTOR4 expression through binding with its intron region, which activates the mTORC1-S6K1 signaling via recruitment of mTORC1 to the lysosomal membrane, ultimately leading to ECs senescence, dysfunction, and vascular aging. Disrupting the GIGYF2-STAU1-mTORC1 signaling cascade may represent a promising therapeutic approach against vascular aging and aging-related cardiovascular diseases.

Deciphering the Functional Status of Breast Cancers through the Analysis of Their Extracellular Vesicles

Breast cancer (BC) accounts for the highest incidence of tumor-related mortality among women worldwide, justifying the growing search for molecular tools for the early diagnosis and follow-up of BC patients under treatment. Circulating extracellular vesicles (EVs) are membranous nanocompartments produced by all human cells, including tumor cells. Since minimally invasive methods collect EVs, which represent reservoirs of signals for cell communication, these particles have attracted the interest of many researchers aiming to improve BC screening and treatment. Here, we analyzed the cargoes of BC-derived EVs, both proteins and nucleic acids, which yielded a comprehensive list of potential markers divided into four distinct categories, namely, (i) modulation of aggressiveness and growth; (ii) preparation of the pre-metastatic niche; (iii) epithelial-to-mesenchymal transition; and (iv) drug resistance phenotype, further classified according to their specificity and sensitivity as vesicular BC biomarkers. We discuss the therapeutic potential of and barriers to the clinical implementation of EV-based tests, including the heterogeneity of EVs and the available technologies for analyzing their content, to present a consistent, reproducible, and affordable set of markers for further evaluation.

Comparing the DNA-damage RBE of intraoperative and conventional electron beams using a hybrid simulation approach

PURPOSE

Employing electron beam for radiotherapy purposes now has been established as one of the standard cancer treatment modalities. Both dedicated intraoperative and conventional electron beams can be employed in patient irradiation. Due to the differences between accelerating structure and electron beam delivery of dedicated intraoperative radiotherapy (IORT) machines and conventional ones, the initial energy spectra of the produced electron beam by these machines may be different. Accordingly, this study aims to evaluate whether these spectral differences can affect the relevant relative biological effectiveness (RBE) values of intraoperative and conventional electron beams.

MATERIALS AND METHODS

A hybrid Monte Carlo simulation approach was considered. At first, the head LIAC12 machine (as an IORT accelerator) and Varian 2100C/D (as a conventional accelerator) were simulated by MCNPX code and electron energy spectra at different depths and off-axis distances were scored for two nominal electron energies of 6 and 12 MeV at the field sizes of 6 and 10 cm. Then, the calculated spectra were imported to MCDS code to estimate the induced DNA-damage RBE values. Finally, the obtained RBE values for intraoperative and conventional electron beams were compared together.

RESULTS

The results showed that the RBE values of the intraoperative electron beam are superior to those obtained for conventional electron beam at the same energy/field size combination. Variations of the depth can regularly affect the RBE value for both conventional and intraoperative electron beams, while no ordered variation trend was observed for RBE with changing the off-axis distance. Variations of electron energy and field size can also influence the RBE value for both types of studied electron beams.

CONCLUSIONS

From the results, it can be concluded the structural differences between the dedicated IORT and conventional Linacs can lead to distinct initial electron energy spectra for intraoperative and conventional electron beams. These physical differences can finally lead to different RBE values for intraoperative and conventional electron beams at the same energy and field size.

Race and Ethnicity Impacts Overall Survival of Patients with Appendiceal Cancer Who Undergo Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy

Appendiceal cancer treatment may include cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). We investigated whether patient race/ethnicity influences outcomes and overall survival for patients with appendiceal cancer who undergo CRS/HIPEC. We queried the National Cancer Database for adult patients with appendiceal cancer treated with CRS/HIPEC from 2006 to 2018. Patients were stratified by race/ethnicity: non-Hispanic White (NHW), non-Hispanic Black (NHB), Hispanic, and Other. Sociodemographics and outcomes were compared using descriptive statistics. Kaplan-Meier survival analysis and Log-rank tests assessed differences in overall survival (OS). Cox Multivariate Regression evaluated factors associated with OS. In total, 2532 patients were identified: 2098 (82.9%) NHW, 186 (7.3%) NHB, 127 (5.0%) Hispanic, and 121 (4.8%) Other patients. The sociodemographics were statistically different across groups. The perioperative and postoperative outcomes were similar. OS was significantly different by race/ethnicity (p = 0.0029). NHB patients compared to Hispanic patients had the shortest median OS (106.7 vs. 145.9 months, p = 0.0093). Race/ethnicity was independently associated with OS: NHB (HR: 2.117 [1.306, 3.431], p = 0.0023) and NHW (HR: 1.549 [1.007, 2.383], p = 0.0463) patients compared to Hispanic patients had worse survival rates. Racial/ethnic disparities exist for patients with appendiceal cancer undergoing CRS/HIPEC. Despite having similar tumor and treatment characteristics, OS is associated with patient race/ethnicity.

The Applications of High-Intensity Focused Ultrasound (HIFU) Ablative Therapy in the Treatment of Primary Breast Cancer: A Systematic Review

BACKGROUND

This study evaluates the role of high-intensity focused ultrasound (HIFU) ablative therapy in treating primary breast cancer.

METHODS

PubMed and Scopus databases were searched according to the PRISMA guidelines to identify studies from 2002 to November 2022. Eligible studies were selected based on criteria such as experimental study type, the use of HIFU therapy as a treatment for localised breast cancer with objective clinical evaluation, i.e., clinical, radiological, and pathological outcomes. Nine studies were included in this study.

RESULTS

Two randomised controlled trials and seven non-randomised clinical trials fulfilled the inclusion criteria. The percentage of patients who achieved complete (100%) coagulation necrosis varied from 17% to 100% across all studies. Eight of the nine studies followed the treat-and-resect protocol in which HIFU-ablated tumours were surgically resected for pathological evaluation. Most breast cancers were single, solitary, and palpable breast tumours. Haematoxylin and eosin stains used for histopathological evaluation showed evidence of coagulation necrosis. Radiological evaluation by MRI showed an absence of contrast enhancement in the HIFU-treated tumour and 1.5 to 2 cm of normal breast tissue, with a thin peripheral rim of enhancement indicative of coagulation necrosis. All studies did not report severe complications, i.e., haemorrhage and infection. Common complications related to HIFU ablation were local mammary oedema, pain, tenderness, and mild to moderate burns. Only one third-degree burn was reported. Generally, the cosmetic outcome was good. The five-year disease-free survival rate was 95%, as reported in two RCTs.

CONCLUSIONS

HIFU ablation can induce tumour coagulation necrosis in localised breast cancer, with a favourable safety profile and cosmetic outcome. However, there is variable evidence of complete coagulation necrosis in the HIFU-treated tumour. Histopathological evidence of coagulation necrosis has been inconsistent, and there is no reliable radiological modality to assess coagulation necrosis confidently. Further exploration is needed to establish the accurate ablation margin with a reliable radiological modality for treatment and follow-up. HIFU therapy is currently limited to single, palpable breast tumours. More extensive and randomised clinical trials are needed to evaluate HIFU therapy for breast cancer, especially where the tumour is left in situ.

Surgeon Factors Influencing Breast Surgery Outcomes: A Scoping Review to Define the Modern Breast Surgical Oncologist

BACKGROUND

Modern breast surgical oncology incorporates many aspects of care including preoperative workup, surgical management, and multidisciplinary collaboration to achieve favorable oncologic outcomes and high patient satisfaction. However, there is variability in surgical practice and outcomes. This review aims to identify modifiable surgeon factors influencing breast surgery outcomes and provide a definition of the modern breast surgical oncologist.

METHODS

A systematic literature search with additional backward citation searching was conducted. Studies describing modifiable surgeon factors with associated breast surgery outcomes such as rates of breast conservation, sentinel node biopsy, re-excision, complications, acceptable esthetic outcome, and disease-free and overall survival were included. Surgeon factors were categorized for qualitative analysis.

RESULTS

A total of 91 studies met inclusion criteria describing both modifiable surgeon factor and outcome data. Four key surgeon factors associated with improved breast surgery outcomes were identified: surgical volume (45 studies), use of oncoplastic techniques (41 studies), sub-specialization in breast surgery or surgical oncology (9 studies), and participation in professional development activities (5 studies).

CONCLUSIONS

On the basis of the literature review, the modern breast surgical oncologist has a moderate- to high-volume breast surgery practice, understands the use and application of oncoplastic breast surgery, engages in additional training opportunities, maintains memberships in relevant societies, and remains up to date on key literature. Surgeons practicing in breast surgical oncology can target these modifiable factors for professional development and quality improvement.

Recent progress in exosome research: isolation, characterization and clinical applications

Exosomes, a kind of nano-vesicles released by various cell types, carry a variety of "cargos" including proteins, RNAs, DNAs and lipids. There is substantial evidence that exosomes are involved in intercellular communication by exchanging "cargos" among cells and play important roles in cancer development. Because of the different expressions of "cargos" carried by exosomes in biological fluids under physiological and pathological conditions, exosomes have the potential as a minimally invasive method of liquid biopsy for cancer diagnosis and prognosis. In addition, due to their good biocompatibility, safety, biodistribution and low immunogenicity, exosomes also have potential applications in the development of promising cancer treatment methods. In this review, we summarize the recent progress in the isolation and characterization techniques of exosomes. Moreover, we review the biological functions of exosomes in regulating tumor metastasis, drug resistance and immune regulation during cancer development and outline the applications of exosomes in cancer therapy.

Combination of specific proteins as markers for accurate detection of extracellular vesicles using proximity ligation-mediated bHCR amplification

As the molecular characteristics of extracellular vesicles (EVs) are closely related to the occurrence and progression of cancer, the detection of tumor-derived EVs provides a promising non-invasive tool for the early diagnosis and treatment of cancer. However, it would be difficult for most of the existing methods to avoid false positives because the obtained result declares the amounts of proteins, but cannot accurately reflect the protein sources, including EV proteins and interfering proteins, in the actual samples. In this manuscript, a robust, accurate, and sensitive fluorescent strategy for profiling EV proteins is developed by using the combination of specific proteins as markers (Co-marker). Our strategy relies on the Co-marker recognition-activated cascade bHCR amplification, which forms numerous G-quadruplex structures that are integrated with fluorescent dyes for signal transduction. Notably, the detection accuracy can be improved owing to the effective avoidance of false positives from interfering proteins or single protein markers. Moreover, by using the double-positive protein recognition mode, unpurified detection can be achieved that avoids time-consuming EVs purification procedures. With its capacities of accuracy, portability, sensitivity, high throughput, and non-purification, the developed strategy might provide a practical tool for EV identification and the related early diagnosis and treatment of cancer.

Comprehensive Detection of PD-L1 Protein and mRNA in Tumor Cells and Extracellular Vesicles through a Real-Time qPCR Assay

A growing number of studies have shown that tumor cells secrete extracellular vesicles (EVs) containing programmed death-ligand 1 (PD-L1) protein. These vesicles can travel to lymph nodes and remotely inactivate T cells, thereby evading immune system attack. Therefore, the simultaneous detection of PD-L1 protein expression in cells and EVs is of great significance in guiding immunotherapy. Herein, we developed a method based on qPCR for the simultaneous detection of PD-L1 protein and mRNA in EVs and their parental cells (PREC-qPCR assay). Lipid probes immobilized on magnetic beads were used to capture EVs directly from samples. For RNA assay, EVs were directly broken by heating and quantified with qPCR. As to protein assay, EVs were recognized and bound with specific probes (such as aptamers), which were used as templates in subsequent qPCR analysis. This method was used to analyze EVs of patient-derived tumor clusters (PTCs) and plasma samples from patients and healthy volunteers. The results revealed that the expression of exosomal PD-L1 in PTCs was correlated with tumor types and significantly higher in plasma-derived EVs from tumor patients than that of healthy individuals. When extended to cells and PD-L1 mRNAs, the results showed that the expression of PD-L1 protein was consistent with mRNA in cancer cell lines, while PTCs demonstrated significant heterogeneity. This comprehensive detection of PD-L1 at four levels (cell, EVs, protein, and mRNA) is believed to enhance our understanding of the relationship among PD-L1, tumors, and the immune system and to provide a promising tool for predicting the benefits of immunotherapy.

Surgical resection for liver recurrence after curative resection of pancreatic ductal adenocarcinoma

PURPOSE

This study aimed to evaluate the clinical significance of surgical resection for liver recurrence in patients with curatively resected pancreatic ductal adenocarcinoma.

METHODS

The medical records of patients with a liver recurrence after undergoing curative pancreatectomy for pancreatic ductal adenocarcinoma were retrospectively reviewed. Clinicopathological and prognostic factors were analyzed, as was the clinical impact of surgical resection for liver recurrence.

RESULTS

Overall, 502 patients underwent curative pancreatic ductal adenocarcinoma resection. Of the 311 patients with recurrence after curative pancreatectomy, 71 (23%) had an initial recurrence in the liver, with 35 having solitary recurrence (11%). Patients with solitary, two or three, or more than four recurrences had median overall survival times of 28.5, 18.0, and 12.2 months, respectively (p < 0.001). Surgical indications for liver recurrence in our institution included solitary tumor, good disease control under chemotherapy after recurrence for > 6 months, and sufficient remnant liver function. Ten patients who met our institutional policy inclusion criteria underwent liver resection. Among 35 patients with initially solitary liver recurrence, those who underwent liver resection outlived those who did not (57.6 months vs. 20.1 months, p < 0.001). In multivariate analysis of overall survival, solitary liver recurrence and liver resection were independent favorable prognostic factors in patients with initial liver recurrence.

CONCLUSION

In selected patients with solitary liver recurrence after curatively resected pancreatic ductal adenocarcinoma, liver resection may be a treatment option.

The lipid composition of extracellular vesicles: applications in diagnostics and therapeutic delivery

Extracellular vesicles (EVs), including exosomes, with nanoscale sizes, biological origins, various functions, and unique lipid and protein compositions have been introduced as versatile tools for diagnostic and therapeutic medical applications. Numerous studies have reported the importance of the lipid composition of EVs and its influence on their mechanism of action. For example, changes in the lipidomic profile of EVs have been shown to influence the progression of various diseases, including ovarian malignancies and prostate cancer. In this review, we endeavored to examine differences in the lipid content of EV membranes derived from different cell types to characterize their capabilities as diagnostic tools and treatments for diseases like cancer and Alzheimer's disease. We additionally discuss designing functionalized vesicles, whether synthetically by hybrid methods or by changing the lipid composition of natural EVs. Lastly, we provide an overview of current and potential biomedical applications and perspectives on the future of this growing field.

A DNA-based hydrogel for exosome separation and biomedical applications

Exosomes (EXOs) have been proven as biomarkers for disease diagnosis and agents for therapeutics. Great challenge remains in the separation of EXOs with high-purity and low-damage from complex biological media, which is critical for the downstream applications. Herein, we report a DNA-based hydrogel to realize the specific and nondestructive separation of EXOs from complex biological media. The separated EXOs were directly utilized in the detection of human breast cancer in clinical samples, as well as applied in the therapeutics of myocardial infarction in rat models. The materials chemistry basis of this strategy involved the synthesis of ultralong DNA chains via an enzymatic amplification, and the formation of DNA hydrogels through complementary base-pairing. These ultralong DNA chains that contained polyvalent aptamers were able to recognize and bind with the receptors on EXOs, and the specific and efficient binding ensured the selective separation of EXOs from media into the further formed networked DNA hydrogel. Based on this DNA hydrogel, rationally designed optical modules were introduced for the detection of exosomal pathogenic microRNA, which achieved the classification of breast cancer patients versus healthy donors with 100% precision. Furthermore, the DNA hydrogel that contained mesenchymal stem cell-derived EXOs was proved with significant therapeutic efficacy in repairing infarcted myocardium of rat models. We envision that this DNA hydrogel-based bioseparation system is promising as a powerful biotechnology, which will promote the development of extracellular vesicles in nanobiomedicine.

Tumor Deposit Is an Independent Factor Predicting Early Recurrence and Poor Prognosis in Gastric Cancer

BACKGROUND

Accurate prognostic estimation is crucial; however, the prognostic value of tumor deposits in gastric cancer remains controversial. This study aimed to investigate their prognostic significance.

METHODS

Clinicopathological and prognostic data of 1012 gastric cancer patients who underwent R0 or R1 surgery from 2010 to 2017 at the Osaka International Cancer Institute were retrospectively reviewed.

RESULTS

Overall, 6.3% patients had tumor deposits, which were associated with Borrmann type, surgical procedure, type of gastrectomy, extent of lymphadenectomy, tumor size, histology, pT, pN, pM, pStage, lymphatic invasion, vascular invasion, preoperative chemotherapy, and postoperative chemotherapy. Tumor deposit-positive patients had worse 5-year disease-free survival (32.60% vs. 92.45%) and overall survival (41.22% vs. 89.37%) than tumor deposit-negative patients. Subgroup analysis regarding pStage II-III also showed significant differences between patients with and without tumor deposits for 5-year disease-free survival (34.15% vs. 80.98%) and overall survival (43.17% vs. 75.78%). Multivariable analysis showed that older age, undifferentiated histology, deeper tumor invasion, lymph node metastasis, distant metastasis, and presence of tumor deposits were significantly correlated with early tumor recurrence and shorter survival time; these factors were identified as independent prognostic factors. The 5-year disease-free survival of tumor deposit-positive patients was significantly worse than that of patients in the pStage III group and comparable to that of patients in the pT4, pN3, and pM1 groups. The 5-year overall survival of tumor deposit-positive patients was comparable to that of the pT4, pN3, pM1, and pStage III groups.

CONCLUSIONS

Tumor deposits are strong and independent predictors of tumor recurrence and poor survival.

Systematic Assessment of Small RNA Profiling in Human Extracellular Vesicles

MOTIVATION

Extracellular vesicles (EVs) are produced and released by most cells and are now recognized to play a role in intercellular communication through the delivery of molecular cargo, including proteins, lipids, and RNA. Small RNA sequencing (small RNA-seq) has been widely used to characterize the small RNA content in EVs. However, there is a lack of a systematic assessment of the quality, technical biases, RNA composition, and RNA biotypes enrichment for small RNA profiling of EVs across cell types, biofluids, and conditions.

METHODS

We collected and reanalyzed small RNA-seq datasets for 2756 samples from 83 studies involving 55 with EVs only and 28 with both EVs and matched donor cells. We assessed their quality by the total number of reads after adapter trimming, the overall alignment rate to the host and non-host genomes, and the proportional abundance of total small RNA and specific biotypes, such as miRNA, tRNA, rRNA, and Y RNA.

RESULTS

We found that EV extraction methods varied in their reproducibility in isolating small RNAs, with effects on small RNA composition. Comparing proportional abundances of RNA biotypes between EVs and matched donor cells, we discovered that rRNA and tRNA fragments were relatively enriched, but miRNAs and snoRNA were depleted in EVs. Except for the export of eight miRNAs being context-independent, the selective release of most miRNAs into EVs was study-specific.

CONCLUSION

This work guides quality control and the selection of EV isolation methods and enhances the interpretation of small RNA contents and preferential loading in EVs.

Extracellular Vesicles as Drug Transporters

Extracellular vesicles (EVs) are lipid bilayer-delimited particles. According to their size and synthesis pathway, EVs can be classified into exosomes, ectosomes (microvesicles), and apoptotic bodies. Extracellular vesicles are of great interest to the scientific community due to their role in cell-to-cell communication and their drug-carrying abilities. The study aims to show opportunities for the application of EVs as drug transporters by considering techniques applicable for loading EVs, current limitations, and the uniqueness of this idea compared to other drug transporters. In addition, EVs have therapeutic potential in anticancer therapy (especially in glioblastoma, pancreatic cancer, and breast cancer).

Plasma exosomal hsa_circ_0079439 as a novel biomarker for early detection of gastric cancer

BACKGROUND

Due to the poor prognosis of gastric cancer (GC), early detection methods are urgently needed. Plasma exosomal circular RNAs (circRNAs) have been suggested as novel biomarkers for GC.

AIM

To identify a novel biomarker for early detection of GC.

METHODS

Healthy donors (HDs) and GC patients diagnosed by pathology were recruited. Nine GC patients and three HDs were selected for exosomal whole-transcriptome RNA sequencing. The expression profiles of circRNAs were analyzed by bioinformatics methods and validated by droplet digital polymerase chain reaction. The expression levels and area under receiver operating characteristic curve values of plasma exosomal circRNAs and standard serum biomarkers were used to compare their diagnostic efficiency.

RESULTS

There were 303 participants, including 240 GC patients and 63 HDs, involved in the study. The expression levels of exosomal hsa_circ_0079439 were significantly higher in GC patients than in HDs (P < 0.0001). However, the levels of standard serum biomarkers were similar between the two groups. The area under the curve value of exosomal hsa_circ_0079439 was higher than those of standard biomarkers, including carcinoembryonic antigen, carbohydrate antigen (CA)19-9, CA72-4, alpha-fetoprotein, and CA125 (0.8595 vs 0.5862, 0.5660, 0.5360, 0.5082, and 0.5018, respectively). The expression levels of exosomal hsa_circ_0079439 were significantly decreased after treatment (P < 0.05). Moreover, the expression levels of exosomal hsa_circ_0079439 were obviously higher in early GC (EGC) patients than in HDs (P < 0.0001).

CONCLUSION

Our results suggest that plasma exosomal hsa_circ_0079439 is upregulated in GC patients. Moreover, the levels of exosomal hsa_circ_0079439 could distinguish EGC and advanced GC patients from HDs. Therefore, plasma exosomal hsa_circ_0079439 might be a potential biomarker for the diagnosis of GC during both the early and late stages.

Omics-Based Investigations of Breast Cancer

Breast cancer (BC) is characterized by an extensive genotypic and phenotypic heterogeneity. In-depth investigations into the molecular bases of BC phenotypes, carcinogenesis, progression, and metastasis are necessary for accurate diagnoses, prognoses, and therapy assessments in predictive, precision, and personalized oncology. This review discusses both classic as well as several novel omics fields that are involved or should be used in modern BC investigations, which may be integrated as a holistic term, onco-breastomics. Rapid and recent advances in molecular profiling strategies and analytical techniques based on high-throughput sequencing and mass spectrometry (MS) development have generated large-scale multi-omics datasets, mainly emerging from the three "big omics", based on the central dogma of molecular biology: genomics, transcriptomics, and proteomics. Metabolomics-based approaches also reflect the dynamic response of BC cells to genetic modifications. Interactomics promotes a holistic view in BC research by constructing and characterizing protein-protein interaction (PPI) networks that provide a novel hypothesis for the pathophysiological processes involved in BC progression and subtyping. The emergence of new omics- and epiomics-based multidimensional approaches provide opportunities to gain insights into BC heterogeneity and its underlying mechanisms. The three main epiomics fields (epigenomics, epitranscriptomics, and epiproteomics) are focused on the epigenetic DNA changes, RNAs modifications, and posttranslational modifications (PTMs) affecting protein functions for an in-depth understanding of cancer cell proliferation, migration, and invasion. Novel omics fields, such as epichaperomics or epimetabolomics, could investigate the modifications in the interactome induced by stressors and provide PPI changes, as well as in metabolites, as drivers of BC-causing phenotypes. Over the last years, several proteomics-derived omics, such as matrisomics, exosomics, secretomics, kinomics, phosphoproteomics, or immunomics, provided valuable data for a deep understanding of dysregulated pathways in BC cells and their tumor microenvironment (TME) or tumor immune microenvironment (TIMW). Most of these omics datasets are still assessed individually using distinct approches and do not generate the desired and expected global-integrative knowledge with applications in clinical diagnostics. However, several hyphenated omics approaches, such as proteo-genomics, proteo-transcriptomics, and phosphoproteomics-exosomics are useful for the identification of putative BC biomarkers and therapeutic targets. To develop non-invasive diagnostic tests and to discover new biomarkers for BC, classic and novel omics-based strategies allow for significant advances in blood/plasma-based omics. Salivaomics, urinomics, and milkomics appear as integrative omics that may develop a high potential for early and non-invasive diagnoses in BC. Thus, the analysis of the tumor circulome is considered a novel frontier in liquid biopsy. Omics-based investigations have applications in BC modeling, as well as accurate BC classification and subtype characterization. The future in omics-based investigations of BC may be also focused on multi-omics single-cell analyses.

The Brain Pre-Metastatic Niche: Biological and Technical Advancements

Metastasis, particularly brain metastasis, continues to puzzle researchers to this day, and exploring its molecular basis promises to break ground in developing new strategies for combatting this deadly cancer. In recent years, the research focus has shifted toward the earliest steps in the formation of metastasis. In this regard, significant progress has been achieved in understanding how the primary tumor affects distant organ sites before the arrival of tumor cells. The term pre-metastatic niche was introduced for this concept and encompasses all influences on sites of future metastases, ranging from immunological modulation and ECM remodeling to the softening of the blood-brain barrier. The mechanisms governing the spread of metastasis to the brain remain elusive. However, we begin to understand these processes by looking at the earliest steps in the formation of metastasis. This review aims to present recent findings on the brain pre-metastatic niche and to discuss existing and emerging methods to further explore the field. We begin by giving an overview of the pre-metastatic and metastatic niches in general before focusing on their manifestations in the brain. To conclude, we reflect on the methods usually employed in this field of research and discuss novel approaches in imaging and sequencing.

Conventional specimen radiography in breast-conserving therapy: a useful tool for intraoperative margin assessment after neoadjuvant therapy?

PURPOSE

A previous study in our breast unit showed that the diagnostic accuracy of intraoperative specimen radiography and its potential to reduce second surgeries in a cohort of patients treated with neoadjuvant chemotherapy were low, which questions the routine use of Conventional specimen radiography (CSR) in this patient group. This is a follow-up study in a larger cohort to further evaluate these findings.

METHODS

This retrospective study included 376 cases receiving breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NACT) of primary breast cancer. CSR was performed to assess potential margin infiltration and recommend an intraoperative re-excision of any radiologically positive margin. The histological workup of the specimen served as gold standard for the evaluation of the accuracy of CSR and the potential reduction of second surgeries by CSR-guided re-excisions.

RESULTS

362 patients with 2172 margins were assessed. The prevalence of positive margins was 102/2172 (4.7%). CSR had a sensitivity of 37.3%, a specificity of 85.6%, a positive predictive value (PPV) of 11.3%, and a negative predictive value (NPV) of 96.5%. The rate of secondary procedures was reduced from 75 to 37 with a number needed to treat (NNT) of CSR-guided intraoperative re-excisions of 10. In the subgroup of patients with clinical complete response (cCR), the prevalence of positive margins was 38/1002 (3.8%), PPV was 6.5% and the NNT was 34.

CONCLUSION

This study confirms our previous finding that the rate of secondary surgeries cannot be significantly reduced by CSR-guided intraoperative re-excisions in cases with cCR after NACT. The routine use CSR after NACT is questionable, and alternative tools of intraoperative margin assessment should be evaluated.

17β-estradiol promotes extracellular vesicle release and selective miRNA loading in ERα-positive breast cancer

The causes and consequences of abnormal biogenesis of extracellular vesicles (EVs) are not yet well understood in malignancies, including in breast cancers (BCs). Given the hormonal signaling dependence of estrogen receptor-positive (ER+) BC, we hypothesized that 17β-estradiol (estrogen) might influence EV production and microRNA (miRNA) loading. We report that physiological doses of 17β-estradiol promote EV secretion specifically from ER+ BC cells via inhibition of miR-149-5p, hindering its regulatory activity on SP1, a transcription factor that regulates the EV biogenesis factor nSMase2. Additionally, miR-149-5p downregulation promotes hnRNPA1 expression, responsible for the loading of let-7's miRNAs into EVs. In multiple patient cohorts, we observed increased levels of let-7a-5p and let-7d-5p in EVs derived from the blood of premenopausal ER+ BC patients, and elevated EV levels in patients with high BMI, both conditions associated with higher levels of 17β-estradiol. In brief, we identified a unique estrogen-driven mechanism by which ER+ BC cells eliminate tumor suppressor miRNAs in EVs, with effects on modulating tumor-associated macrophages in the microenvironment.

Z-Endoxifen prevents aggressive mammary cancers in mice by inhibiting cell proliferation and creating a tumor suppressive microenvironment

Aggressive estrogen receptor (ER) positive breast cancer is frequently tamoxifen-resistant; alternative endocrine approaches exist for therapy, but not for prevention, particularly in premenopausal women. We examined the efficacy of the selective ER modulator (Z-endoxifen) as monotherapy and in combination with the selective progesterone receptor modulators (onapristone and ulipristal acetate) in the tamoxifen-insensitive C3(1)/SV40TAg mouse mammary tumorigenesis model. Unlike tamoxifen at human equivalent dose (HED) 101 mg/day, endoxifen at HED 24 mg/day significantly increased latency and reduced tumor growth relative to untreated controls. Ulipristal acetate (UPA) at HED 81 mg/day also significantly increased latency however failed to inhibit tumor growth, while onapristone (HED 98 mg/day) had no tumor prevention efficacy in this model. Addition of UPA to endoxifen did not enhance preventive efficacy over endoxifen alone. The expression of genes associated with cell cycle, cell proliferation and extracellular matrix remodeling was similarly repressed by endoxifen and UPA however only endoxifen significantly downregulated prominent genes associated with poor prognosis (Col11a1, Il17b, Pdgfa, Tnfrsf11a). Our results indicate that endoxifen can prevent breast cancers, even when tamoxifen-resistant, through its role in favorable tissue remodeling and immunomodulation.

Multigene profiles to guide the use of neoadjuvant chemotherapy for breast cancer: a Copenhagen Breast Cancer Genomics Study

Estrogen receptor (ER) and human epidermal growth factor 2 (HER2) expression guide the use of neoadjuvant chemotherapy (NACT) in patients with early breast cancer. We evaluate the independent predictive value of adding a multigene profile (CIT256 and PAM50) to immunohistochemical (IHC) profile regarding pathological complete response (pCR) and conversion of positive to negative axillary lymph node status. The cohort includes 458 patients who had genomic profiling performed as standard of care. Using logistic regression, higher pCR and node conversion rates among patients with Non-luminal subtypes are shown, and importantly the predictive value is independent of IHC profile. In patients with ER-positive and HER2-negative breast cancer an odds ratio of 9.78 (95% CI 2.60;36.8), P < 0.001 is found for pCR among CIT256 Non-luminal vs. Luminal subtypes. The results suggest a role for integrated use of up-front multigene subtyping for selection of a neoadjuvant approach in ER-positive HER2-negative breast cancer.

The Importance of Detecting, Quantifying, and Characterizing Exosomes as a New Diagnostic/Prognostic Approach for Tumor Patients

Exosomes are extracellular vesicles (EVs) of nanometric size studied for their role in tumor pathogenesis and progression and as a new source of tumor biomarkers. The clinical studies have provided encouraging but probably unexpected results, including the exosome plasmatic levels' clinical relevance and well-known biomarkers' overexpression on the circulating EVs. The technical approach to obtaining EVs includes methods to physically purify EVs and characterize EVs, such as Nanosight Tracking Analysis (NTA), immunocapture-based ELISA, and nano-scale flow cytometry. Based on the above approaches, some clinical investigations have been performed on patients with different tumors, providing exciting and promising results. Here we emphasize data showing that exosome plasmatic levels are consistently higher in tumor patients than in controls and that plasmatic exosomes express well-known tumor markers (e.g., PSA and CEA), proteins with enzymatic activity, and nucleic acids. However, we also know that tumor microenvironment acidity is a key factor in influencing both the amount and the characteristics of the exosome released by tumor cells. In fact, acidity significantly increases exosome release by tumor cells, which correlates with the number of exosomes that circulate through the body of a tumor patient.