Stimulating T cell responses against patient-derived breast cancer cells with neoantigen peptide-loaded peripheral blood mononuclear cells.

Breast cancer stands as a formidable global health challenge for women. While neoantigens exhibit efficacy in activating T cells specific to cancer and instigating anti-tumor immune responses, the accuracy of neoantigen prediction remains suboptimal. In this study, we identified neoantigens from the patient-derived breast cancer cells, PC-B-142CA and PC-B-148CA cells, utilizing whole-genome and RNA sequencing. The pVAC-Seq pipeline was employed, with minor modification incorporating criteria (1) binding affinity of mutant (MT) peptide with HLA (IC50 MT) ≤ 500 nm in 3 of 5 algorithms and (2) IC50 wild type (WT)/MT > 1. Sequencing results unveiled 2513 and 3490 somatic mutations, and 646 and 652 non-synonymous mutations in PC-B-142CA and PC-B-148CA, respectively. We selected the top 3 neoantigens to perform molecular dynamic simulation and synthesized 9-12 amino acid neoantigen peptides, which were then pulsed onto healthy donor peripheral blood mononuclear cells (PBMCs). Results demonstrated that T cells activated by ADGRL1E274K, PARP1E619K, and SEC14L2R43Q peptides identified from PC-B-142CA exhibited significantly increased production of interferon-gamma (IFN-γ), while PARP1E619K and SEC14L2R43Q peptides induced the expression of CD107a on T cells. The % tumor cell lysis was notably enhanced by T cells activated with MT peptides across all three healthy donors. Moreover, ALKBH6V83M and GAAI823T peptides from PC-B-148CA remarkably stimulated IFN-γ- and CD107a-positive T cells, displaying high cell-killing activity against target cancer cells. In summary, our findings underscore the successful identification of neoantigens with anti-tumor T cell functions and highlight the potential of personalized neoantigens as a promising avenue for breast cancer treatment.

Enhancement of PD-L1-attenuated CAR-T cell function through breast cancer-associated fibroblasts-derived IL-6 signaling via STAT3/AKT pathways.

BACKGROUND: Carcinoma-associated fibroblasts (CAFs) play a critical role in cancer progression and immune cell modulation. In this study, it was aimed to evaluate the roles of CAFs-derived IL-6 in doxorubicin (Dox) resistance and PD-L1-mediated chimeric antigenic receptor (CAR)-T cell resistance in breast cancer (BCA). METHODS: CAF conditioned-media (CM) were collected, and the IL-6 level was measured by ELISA. CAF-CM were treated in MDA-MB-231 and HCC70 TNBC cell lines and siIL-6 receptor (IL-6R) knocked down (KD) cells to determine the effect of CAF-derived IL-6 on Dox resistance by flow cytometry and on increased PD-L1 through STAT3, AKT and ERK1/2 pathways by Western blot analysis. After pre-treating with CM, the folate receptor alpha (FRα)-CAR T cell cytotoxicity was evaluated in 2D and 3D spheroid culture assays. RESULTS: The results showed a significant level of IL-6 in CAF-CM compared to that of normal fibroblasts (NFs). The CM with high IL-6 level significantly induced Dox resistance; and PD-L1 expression through STAT3 and AKT pathways in MDA-MB-231 and HCC70 cells. These induction effects were attenuated in siIL-6R KD cells. Moreover, the TNBC cell lines that were CM-treated with STAT3 and an AKT inhibitor had a reduced effect of IL-6 on PD-L1 expression. BCA cells with high IL-6 containing-CM treatment had resistance to cancer cell killing by FRα CAR-T cells compared to untreated cells. CONCLUSION: These results highlight CAF-derived IL-6 in the resistance of chemotherapy and T cell therapy. Using inhibitors of IL6-STAT3/AKT-PD-L1 axis may provide a potential benefit of Dox and CAR-T cell therapies in BCA patients.

HMGB1 mediates invasion and PD-L1 expression through RAGE-PI3K/AKT signaling pathway in MDA-MB-231 breast cancer cells.

BACKGROUND: High-mobility group box 1 (HMGB1) is increased in breast cancer cells as the result of exposure to the secreted substances from cancer-associated fibroblasts and plays a crucial role in cancer progression and drug resistance. Its effect, however, on the expression of programmed death ligand 1 (PD-L1) in breast cancer cells has not been investigated. This study aimed to investigate the mechanism of HMGB1 through receptors for advanced glycation end products (RAGE) on cell migration/invasion and PD-L1 expression in breast cancer cells. METHODS: A 3-dimensional (3-D) migration and invasion assay and Western blotting analysis to evaluate the function and the mechanism under recombinant HMGB1 (rHMGB1) treatment with knockdown of RAGE using shRAGE and PI3K/AKT inhibitors was performed. RESULTS: The results revealed that rHMGB1 induced MDA-MB-231 cell migration and invasion. The knockdown of RAGE using shRAGE and PI3K/AKT inhibitors attenuated 3-D migration and invasion in response to rHMGB1 compared to mock cells. PD-L1 up-regulation was observed in both parental MDA-MB-231 (P) and MDA-MB-231 metastasis to bone marrow (BM) cells treated with rHMGB1, and these effects were alleviated in RAGE-knock down (KD) breast cancer cells as well as in PI3K/AKT inhibitor-treated cells. CONCLUSIONS: Collectively, these findings indicate that HMGB1-RAGE through PI3K/AKT signaling promotes not only breast cancer cell invasion but also PD-L1 expression which leads to the destruction of the effector T cells. The attenuating HMGB1-RAGE-PI3K/AKT pathway may help to attenuate breast cancer cell aggressive phenotypes.

Diagnostic power of DNA methylation markers suggestive of cholangiocarcinoma in ERCP-based brush cytology.

BACKGROUND AND AIMS: Accurate differentiation between cholangiocarcinoma (CCA) and benign biliary stricture is of paramount importance. Biliary brush cytology is a simple and safe diagnostic approach that provides relatively high specificity; however, sensitivity is limited. Previous reports indicated the aberrations of DNA methylation in CCA. This study aimed to investigate the diagnostic performance of the methylation index (MI) of HOXA1 and NEUROG1 gene promoters in CCA. METHODS: Patients with biliary stricture who underwent ERCP with brush cytology in Siriraj Hospital from September 2016 to December 2019 were prospectively enrolled. The MI of HOXA1 (MI_H) and MI of NEUROG1 (MI_N) were determined by quantitative methylation-specific polymerase chain reaction. The diagnostic power for CCA was tested for MI from both genes and serum carbohydrate antigen 19-9 (CA19-9). RESULTS: Sixty-seven patients were included in the study; 41 patients had a final diagnosis of CCA, and 26 patients were determined to have a benign biliary stricture. The results showed that both MI_H and MI_N had higher sensitivity and accuracy (95.1% and 82.3% and 90.2% and 89.5%, respectively) than brush cytology (61.5% and 78.1%) and CA19-9 (69.4% and 77.8%). The combination of brush cytology, both methylation markers, and CA19-9 increased the sensitivity and accuracy to 97.4% and 91.0%. Methylation markers were positive in 5 of 6 patients with confirmed CCA whose cytology and CA19-9 were negative. CONCLUSIONS: DNA methylation increased the sensitivity for the diagnosis of CCA; therefore, the use of DNA methylation is promising for diagnosis of CCA in patients with biliary strictures. A future validation study is warranted to assess its role in clinical practice. (Clinical trial registration number: NCT04568512.).

Development of an engineered peptide antagonist against periostin to overcome doxorubicin resistance in breast cancer.

BACKGROUND: Chemoresistance is one of the main problems in treatment of cancer. Periostin (PN) is a stromal protein which is mostly secreted from cancer associated fibroblasts in the tumor microenvironment and can promote cancer progression including cell survival, metastasis, and chemoresistance. The main objective of this study was to develop an anti-PN peptide from the bacteriophage library to overcome PN effects in breast cancer (BCA) cells. METHODS: A twelve amino acids bacteriophage display library was used for biopanning against the PN active site. A selected clone was sequenced and analyzed for peptide primary structure. A peptide was synthesized and tested for the binding affinity to PN. PN effects including a proliferation, migration and a drug sensitivity test were performed using PN overexpression BCA cells or PN treatment and inhibited by an anti-PN peptide. An intracellular signaling mechanism of inhibition was studied by western blot analysis. Lastly, PN expressions in BCA patients were analyzed along with clinical data. RESULTS: The results showed that a candidate anti-PN peptide was synthesized and showed affinity binding to PN. PN could increase proliferation and migration of BCA cells and these effects could be inhibited by an anti-PN peptide. There was significant resistance to doxorubicin in PN-overexpressed BCA cells and this effect could be reversed by an anti-PN peptide in associations with phosphorylation of AKT and expression of survivin. In BCA patients, serum PN showed a correlation with tissue PN expression but there was no significant correlation with clinical data. CONCLUSIONS: This finding supports that anti-PN peptide is expected to be used in the development of peptide therapy to reduce PN-induced chemoresistance in BCA.

Periostin regulates autophagy through integrin α5ß1 or α6ß4 and an AKT-dependent pathway in colorectal cancer cell migration.

Colorectal cancer (CRC) is one of the most fatal cancers with highly invasive properties. The progression of CRC is determined by the driving force of periostin (PN) from cancer-associated fibroblasts (CAFs) in the tumour microenvironment. This present work aims to investigate autophagy-mediated CRC invasion via the receptor integrin (ITG) by PN. The level of PN in 410 clinical CRC tissues was found increased and was an independent poor prognosis marker (HR = 2.578, 95% CI = 1.218-5.457, P-value = .013) with a significant correlation with overall survival time (P-value < .001). PN activated proliferation, migration and invasion of CRC cells, but with reduced autophagy. Interestingly, the reduction of LC3 autophagic protein corresponded to the increased ability of CRC cell migration. The siITGα5-treated HT-29 and siITGß4-treated HCT-116 CRC cells attenuated epithelial-to-mesenchymal transitions (EMT)-related genes and pAKT compared with those in siITG-untreated cells. The reduction of pAKT by a PI3K inhibitor significantly restored autophagy in CRC cells. These evidences confirmed the effect of PN through either ITGα5ß1 or ITGα6ß4 and the AKT-dependent pathway to control autophagy-regulated cell migration. In conclusion, these results exhibited the impact of PN activation of ITGα5ß1 or ITGα6ß4 through pAKT in autophagy-mediated EMT and migration in CRC cells.

Inhibition of Tumor Growth against Chemoresistant Cholangiocarcinoma by a Proapoptotic Peptide Targeting Interleukin-4 Receptor.

Cholangiocarcinoma (CCA) has a poor prognosis and high chemoresistance. Interleukin-4 receptor (IL-4R) is overexpressed in several cancer cells and plays a crucial role in tumor progression and drug resistance. IL4RPep-1, an IL-4R-binding peptide, has been identified by phage display and used for tumor targeting. In this study, we exploited IL4RPep-1 to guide the tumor-specific delivery of a proapoptotic peptide to chemoresistant CCA, thereby inhibiting tumor growth. Immunohistochemistry of human primary CCA tissues showed that IL-4R levels were upregulated in moderately to poorly differentiated types, and higher levels of IL-4R are correlated with lower survival rates in patients with CCA. IL4RPep-1 was observed to preferentially bind with high IL-4R-expressing KKU-213 human CCA cells, whereas it barely bound with low IL-4R-expressing KKU-055 cells. A hybrid of IL4RPep-1 and a proapoptotic peptide (KLAKLAK)2 (named as IL4RPep-1-KLA) induced cytotoxicity and apoptosis in KKU-213 cells and increased those levels induced by 5-fluorouracil (5-FU). IL4RPep-1-KLA was internalized in the cells and colocalized with mitochondria. Whole-body fluorescence imaging and immunohistochemical analysis of tumor tissues showed the homing of IL4RPep-1-KLA as well as IL4RPep-1 to KKU-213 tumor in mice. Systemic administration of IL4RPep-1-KLA efficiently inhibited KKU-213 tumor growth, whereas treatment with 5-FU alone did not significantly inhibit tumor growth in mice. No significant systemic side effects including liver toxicity and immunotoxicity were observed in mice during peptide treatments. These findings suggest that IL4RPep-1-KLA holds potential as a targeted therapeutic agent against chemoresistant CCA.

The metabolic cross-talk between epithelial cancer cells and stromal fibroblasts in ovarian cancer progression: Autophagy plays a role.

Cancer and stromal cells, which include (cancer-associated) fibroblasts, adipocytes, and immune cells, constitute a mixed cellular ecosystem that dynamically influences the behavior of each component, creating conditions that ultimately favor the emergence of malignant clones. Ovarian cancer cells release cytokines that recruit and activate stromal fibroblasts and immune cells, so perpetuating a state of inflammation in the stroma that hampers the immune response and facilitates cancer survival and propagation. Further, the stroma vasculature impacts the metabolism of the cells by providing or limiting the availability of oxygen and nutrients. Autophagy, a lysosomal catabolic process with homeostatic and prosurvival functions, influences the behavior of cancer cells, affecting a variety of processes such as the survival in metabolic harsh conditions, the invasive growth, the development of immune and chemo resistance, the maintenance of stem-like properties, and dormancy. Further, autophagy is involved in the secretion and the signaling of promigratory cytokines. Cancer-associated fibroblasts can influence the actual level of autophagy in ovarian cancer cells through the secretion of pro-inflammatory cytokines and the release of autophagy-derived metabolites and substrates. Interrupting the metabolic cross-talk between cancer cells and cancer-associated fibroblasts could be an effective therapeutic strategy to arrest the progression and prevent the relapse of ovarian cancer.

The microRNA-15a-PAI-2 axis in cholangiocarcinoma-associated fibroblasts promotes migration of cancer cells.

BACKGROUND: Cholangiocarcinoma (CCA) has an abundance of tumor stroma which plays an important role in cancer progression via tumor-promoting signals. This study aims to explore the microRNA (miRNA) profile of CCA-associated fibroblasts (CCFs) and the roles of any identified miRNAs in CCA progression. METHODS: miRNA expression profiles of CCFs and normal skin fibroblasts were compared by microarray. Identified downregulated miRNAs and their target genes were confirmed by real-time PCR. Their binding was confirmed by a luciferase reporter assay. The effects of conditioned-media (CM) of miRNA mimic- and antagonist-transfected CCFs were tested in CCA migration in wound healing assays. Finally, the levels of miRNA and their target genes were examined by real-time PCR and immunohistochemistry in clinical CCA samples. RESULTS: miR-15a was identified as a downregulated miRNA in CCFs. Moreover, PAI-2 was identified as a novel target gene of miR-15a. Recombinant PAI-2 promoted migration of CCA cells. Moreover, CM from miR-15a mimic-transfected CCFs suppressed migration of CCA cells. Lower expression of miR-15a and higher expression of PAI-2 were observed in human CCA samples compared with normal liver tissues. Importantly, PAI-2 expression correlated with poor prognosis in CCA patients. CONCLUSIONS: These findings highlight the miR-15a/PAI-2 axis as a potential therapeutic target in CCA patients.

Increased ETV4 expression correlates with estrogen-enhanced proliferation and invasiveness of cholangiocarcinoma cells.

BACKGROUND: Cholangiocarcinoma (CCA) is one of the worst prognosis cancer. The survival time of CCA patients is related to serum estrogen levels and estrogen has been found to enhance the proliferation and invasiveness of CCA cells in vitro. This has led to the suggestion that estrogen may play an important role in the progression of CCA. This study tests the relevance of the previous in vitro findings in vivo using a mouse xenograft model of CCA, and investigates possible signaling mechanisms involved. METHODS: KKU-213 and KKU-139 CCA cell lines were used in the experiments, xenografted to nude mice and treated with a potent estrogenic agent, 17ß-estradiol (E2), and/or with tamoxifen (TAM), an estrogen antagonist. RESULTS: The results demonstrated that E2 could accelerate growth of the xenograft-tumor and the effect was inhibited by TAM. PCR array screening of E2 responsive genes suggested ETV4 as a promising candidate intracellular mediator. ETV4-knockdown CCA cells were generated and these showed a diminished responsiveness to E2 in both cell and spheroid proliferation assays, and in invasion tests. These results point to ETV4 as a possible mediator of E2-activated CCA progression and as a potential target of TAM-mediated inhibition. CONCLUSIONS: Finally, TAM may be suggested as an adjunctive treatment of CCA to improve the conventional cytotoxic method with more patient toleration.

Compound A attenuates toll-like receptor 4-mediated paclitaxel resistance in breast cancer and melanoma through suppression of IL-8.

BACKGROUND: Paclitaxel (PTX) is a potent anti-cancer drug commonly used for the treatment of advanced breast cancer (BCA) and melanoma. Toll-like receptor 4 (TLR4) promotes the production of pro-inflammatory cytokines associated with cancer chemoresistance. This study aims to explore the effect of TLR4 in PTX resistance in triple-negative BCA and advanced melanoma and the effect of compound A (CpdA) to attenuate this resistance. METHODS: BCA and melanoma cell lines were checked for the response to PTX by cytotoxic assay. The response to PTX of TLR4-transient knockdown cells by siRNA transfection was evaluated compared to the control cells. Levels of pro-inflammatory cytokines, IL-6 and IL-8, and anti-apoptotic protein, XIAP were measured by real-time PCR whereas the secreted IL-8 was quantitated by ELISA in TLR4-transient knockdown cancer cells with or without CpdA treatment. The apoptotic cells after adding PTX alone or in combination with CpdA were detected by caspase-3/7 assay. RESULTS: PTX could markedly induce TLR4 expression in both MDA-MB-231 BCA and MDA-MB-435 melanoma cell lines having a basal level of TLR4 whereas no significant induction in TLR4-transient knockdown cells occurred. The siTLR4-treated BCA cells revealed more dead cells after PTX treatment than that of mock control cells. IL-6, IL-8 and XIAP showed increased expressions in PTX-treated cells and this over-production effect was inhibited in TLR4-transient knockdown cells. Apoptotic cells were detected higher when PTX and CpdA were combined than PTX treatment alone. Isobologram exhibited the synergistic effect of CpdA and PTX. CpdA could significantly decrease expressions of IL-6, XIAP and IL-8, as well as excreted IL-8 levels together with reduced cancer viability after PTX treatment. CONCLUSIONS: The acquired TLR4-mediated PTX resistance in BCA and melanoma is explained partly by the paracrine effect of IL-6 and IL-8 released into the tumor microenvironment and over-production of anti-apoptotic protein, XIAP, in BCA cells and importantly CpdA could reduce this effect and sensitize PTX-induced apoptosis in a synergistic manner. In conclusion, the possible impact of TLR4-dependent signaling pathway in PTX resistance in BCA and melanoma is proposed and using PTX in combination with CpdA may attenuate TLR4-mediated PTX resistance in the treatment of the patients.

Cancer-associated fibroblasts induce high mobility group box 1 and contribute to resistance to doxorubicin in breast cancer cells.

BACKGROUND: Cancer-associated fibroblasts and high mobility group box 1 (HMGB1) protein have been suggested to mediate cancer progression and chemotherapy resistance. The role of such fibroblasts in HMGB1 production in breast cancer is unclear. This study aimed to investigate the effects of cancer-associated fibroblasts on HMGB1 expression in breast cancer cells and its role in chemotherapeutic response. METHODS: Breast cancer-associated fibroblasts (BCFs) and non-tumor-associated fibroblasts (NTFs) were isolated from human breast cancers or adjacent normal tissues and established as primary cultures in vitro. After confirmation of the activated status of these fibroblasts, conditioned-media (CM) were collected and applied to MDA-MB-231 human triple negative breast cancer cells. The levels of intracellular and extracellular HMGB1 were measured by real-time PCR and/or Western blot. The response of BCF-CM-pre-treated cancer cells to doxorubicin (Dox) was compared with those pre-treated with NTF-CM or control cultures. The effect of an HMGB1 neutralizing antibody on Dox resistance induced by extracellular HMGB1 from non-viable Dox-treated cancer cells or recombinant HMGB1 was also investigated. RESULTS: Immunocytochemical analysis revealed that BCFs and NTFs were alpha-smooth muscle actin (ASMA) positive and cytokeratin 19 (CK19) negative cells: a phenotype consistent with that of activated fibroblasts. We confirmed that the CM from BCFs (but not NTFs), could significantly induce breast cancer cell migration. Intracellular HMGB1 expression was induced in BCF-CM-treated breast cancer cells and also in Dox-treated cells. Extracellular HMGB1 was strongly expressed in the CM after Dox-induced MDA-MB-231 cell death and was higher in cells pre-treated with BCF-CM than NTF-CM. Pre-treatment of breast cancer cells with BCF-CM induced a degree of resistance to Dox in accordance with the increased level of secreted HMGB1. Recombinant HMGB1 was shown to increase Dox resistance and this was associated with evidence of autophagy. Anti-HMGB1 neutralizing antibody significantly reduced the effect of extracellular HMGB1 released from dying cancer cells or of recombinant HMGB1 on Dox resistance. CONCLUSIONS: These findings highlight the potential of stromal fibroblasts to contribute to chemoresistance in breast cancer cells in part through fibroblast-induced HMGB1 production.

Public neoantigens in breast cancer immunotherapy (Review).

Among women globally, breast cancer is the most prevalent cancer and the leading cause of cancer­related death. Interestingly, though genetic mutations contribute to the disease, <15% of women diagnosed with breast cancer have a family history of the disease, suggesting a prevalence of sporadic genetic mutations in breast cancer development. In the rapidly rising field of cancer genomics, neoantigen­based immunotherapy has come to the fore. The investigation of novel proteins arising from unique somatic mutations or neoantigens have opened a new pathway for both individualized and public cancer treatments. Because they are shared among individuals with similar genetic changes, public neoantigens provide an opportunity for 'off­the­shelf' anticancer therapies, potentially extending the benefits to a wider patient group. The present review aimed to highlight the role of shared or public neoantigens as therapeutic targets for patients with breast cancer, emphasizing common hotspot mutations of certain genes identified in breast cancer. The clinical utilization of public neoantigen­based therapies for breast cancer treatment were also discussed.

The combined tumour-based Fascin/Snail and stromal periostin reveals the effective prognosis prediction in colorectal cancer patients.

Colorectal cancer (CRC) is the third most common malignancy cause of cancer-related mortality worldwide. Epithelial-mesenchymal transition (EMT) promotes cancer metastasis and a tumour-based Glasgow EMT score was associated with adverse clinical features and poor prognosis. In this study, the impact of using the established five tumour-based EMT markers consisting of E-cadherin (E-cad), ß-catenin (ß-cat), Snail, Zeb-1, and Fascin in combination with the stromal periostin (PN) on the prediction of CRC patients' prognosis were invesigated. Formalin-fixed paraffin-embedded tissues of 202 CRC patients were studies the expressions of E-cad, ß-cat, Snail, Zeb-1, Fascin, and PN by immunohistochemistry. Individually, cytoplasmic Fascin (Fc), cytoplasmic Snail (Sc), nuclear Snail (Sn), stromal Snail (Ss), and stromal PN (Ps) were significantly associated with reduced survival. A combination of Ps with Fc, Fs, and Sn was observed in 2 patterns including combined Fc, Fs, and Ps (FcFsPs) and Fc, Sn, and Ps (FcSnPs). These combinations enhanced the prognostic power compared to individual EMT markers and were independent prognostic markers. As the previously established scoring method required five markers and stringent criteria, its clinical use might be limited. Therefore, using these novel combined prognostic markers, either FcFsPs or FcSnPs, may be useful in predicting CRC patient outcomes.

Detection of centroblast cells in H&E stained whole slide image based on object detection.

Introduction: Detection and counting of Centroblast cells (CB) in hematoxylin & eosin (H&E) stained whole slide image (WSI) is an important workflow in grading Lymphoma. Each high power field (HPF) patch of a WSI is inspected for the number of CB cells and compared with the World Health Organization (WHO) guideline that organizes lymphoma into 3 grades. Spotting and counting CBs is time-consuming and labor intensive. Moreover, there is often disagreement between different readers, and even a single reader may not be able to perform consistently due to many factors. Method: We propose an artificial intelligence system that can scan patches from a WSI and detect CBs automatically. The AI system works on the principle of object detection, where the CB is the single class of object of interest. We trained the AI model on 1,669 example instances of CBs that originate from WSI of 5 different patients. The data was split 80%/20% for training and validation respectively. Result: The best performance was from YOLOv5x6 model that used the preprocessed CB dataset achieved precision of 0.808, recall of 0.776, mAP at 0.5 IoU of 0.800 and overall mAP of 0.647. Discussion: The results show that centroblast cells can be detected in WSI with relatively high precision and recall.

Cytotoxicity of fourth-generation anti-Trop2 CAR-T cells against breast cancer.

The treatment of breast cancer (BC) remains a formidable challenge due to the emergence of drug resistance, necessitating the exploration of innovative strategies. Chimeric antigen receptor (CAR)-T cell therapy, a groundbreaking approach in hematologic malignancies, is actively under investigation for its potential application in solid tumors, including BC. Trophoblast cell surface antigen 2 (Trop2) has emerged as a promising immunotherapeutic target in various cancers and is notably overexpressed in BC. To enhance therapeutic efficacy in BC, a fourth-generation CAR (CAR4) construct was developed. This CAR4 design incorporates an anti-Trop2 single-chain variable fragment (scFv) fused with three costimulatory domains -CD28/4-1BB/CD27, and CD3ζ. Comparative analysis with the conventional second-generation CAR (CAR2; 28ζ) revealed that anti-Trop2 CAR4 T cells exhibited heightened cytotoxicity and interferon-gamma (IFN-γ) production against Trop2-expressing MCF-7 cells. Notably, anti-Trop2 CAR4-T cells demonstrated superior long-term cytotoxic functionality and proliferative capacity. Crucially, anti-Trop2 CAR4-T cells displayed specific cytotoxicity against Trop2-positive BC cells (MDA-MB-231, HCC70, and MCF-7) in both two-dimensional (2D) and three-dimensional (3D) culture systems. Following antigen-specific killing, these cells markedly secreted interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-α), IFN-γ, and Granzyme B compared to non-transduced T cells. This study highlights the therapeutic potential of anti-Trop2 CAR4-T cells in adoptive T cell therapy for BC, offering significant promise for the advancement of BC treatment strategies.

PseudoCell: Hard Negative Mining as Pseudo Labeling for Deep Learning-Based Centroblast Cell Detection.

Background: Deep learning models for patch classification in whole-slide images (WSIs) have shown promise in assisting follicular lymphoma grading. However, these models often require pathologists to identify centroblasts and manually provide refined labels for model optimization. Objective: To address this limitation, we propose PseudoCell, an object detection framework for automated centroblast detection in WSI, eliminating the need for extensive pathologist's refined labels. Methods: PseudoCell leverages a combination of pathologist-provided centroblast labels and pseudo-negative labels generated from undersampled false-positive predictions based on cell morphology features. This approach reduces the reliance on time-consuming manual annotations. Results: Our framework significantly reduces the workload for pathologists by accurately identifying and narrowing down areas of interest containing centroblasts. Depending on the confidence threshold, PseudoCell can eliminate 58.18-99.35% of irrelevant tissue areas on WSI, streamlining the diagnostic process. Conclusion: This study presents PseudoCell as a practical and efficient prescreening method for centroblast detection, eliminating the need for refined labels from pathologists. The discussion section provides detailed guidance for implementing PseudoCell in clinical practice.

Nucleolin­based targeting strategies in cancer treatment: Focus on cancer immunotherapy (Review).

The benefits of treating several types of cancers using immunotherapy have recently been established. The overexpression of nucleolin (NCL) in a number of types of cancer provides an attractive antigen target for the development of novel anticancer immunotherapeutic treatments. NCL is a multifunctional protein abundantly distributed in the nucleus, cytoplasm and cell membrane. It influences carcinogenesis, and the proliferation, survival and metastasis of cancer cells, leading to cancer progression. Additionally, the meta­analysis of total and cytoplasmic NCL overexpression indicates a poor prognosis of patients with breast cancer. The AS1411 aptamers currently appear to have therapeutic action in the phase II clinical trial. The authors' research group has recently explored the anticancer function of NCL through the activation of T cells by dendritic cell­based immunotherapy. The present review describes and discusses the mechanisms through which the multiple functions of NCL can participate in the progression of cancer. In addition, the studies that define the utility of NCL­dependent anticancer therapies are summarized, with specific focus being paid to cancer immunotherapeutic approaches.

Novel CSF1R-positive tenosynovial giant cell tumor cell lines and their pexidartinib (PLX3397) and sotuletinib (BLZ945)-induced apoptosis.

Tenosynovial giant cell tumor (TGCT) is a mesenchymal tumor derived from the synovium of the tendon sheath and joints, most frequently in the large joints. The standard of care for TGCTs is surgical resection. A new targeting approach for treating TGCTs has emerged from studies on the role of the CSF1/CSF1 receptor (CSF1R) in controlling cell survival and proliferation during the pathogenesis of TGCTs. We established four novel cell lines isolated from the primary tumor tissues of patients with TGCTs. The cell lines were designated Si-TGCT-1, Si-TGCT-2, Si-TGCT-3, and Si-TGCT-4, and the TGCT cells were characterized by CSF1R and CD68. These TGCT cells were then checked for cell proliferation using an MTT assay and three-dimensional spheroid. The responses to pexidartinib (PLX3397) and sotuletinib (BLZ945) were evaluated by two-dimensional MTT assays. All cells were positive for α­smooth muscle actin (α­SMA), fibroblast activation protein (FAP), CSF1R, and CD68. Except for Si-TGCT-4, all TGCT cells had high CSF1R expressions. The cells exhibited continuous growth as three-dimensional spheroids formed. Treatment with pexidartinib and sotuletinib inhibited TGCT cell growth and induced cell apoptosis correlated with the CSF1R level. Only Si-TGCT-4 cells demonstrated resistance to the drugs. In addition, the BAX/BCL-2 ratio increased in cells treated with pexidartinib and sotuletinib. With the four novel TGCT cell lines, we have an excellent model for further in vitro and in vivo studies.

Mesothelin­specific T cell cytotoxicity against triple negative breast cancer is enhanced by 40s ribosomal protein subunit 3­treated self­differentiated dendritic cells.

Triple negative breast cancer (TNBC) lacks targeted treatment resulting in poor prognosis. Targeting overexpressing mesothelin (MSLN) using MSLN­specific T cells is an attractive treatment approach and the aim of the present study. The expression of MSLN in human TNBC paraffin sections was analyzed by immunohistochemistry. Lentiviral vector harbored granulocyte­macrophage colony stimulating factor (GM­CSF), interleukin­4 (IL­4) and MSLN cDNAs was constructed to generate self­differentiated myeloid­derived antigen­presenting­cells reactive against tumor expressing MSLN dendritic cell (MSLN­SmartDC) for MSLN­specific T cell activation. The results showed high MSLN in 32.8% of all breast cancer subtypes and 57% in TNBC. High MSLN was significantly associated with TNBC subtype and the absence of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. MSLN­SmartDC exhibited comparable phenotype to DC generated by exogenous cytokine treatment and an addition of 40s ribosomal protein subunit 3 (RPS3), a toll­like receptor 4 ligand, enhanced DC maturation and function by upregulation of CD40, CD80 and CD83 expressions and IL­12p70 secretion. MSLN­specific CD8+CD69+ IFN­Î³+ T cells were detected in T cells activated by both MSLN­SmartDC and RPS3­MSLN­SmartDC. MSLN­specific T cells activated by these DCs showed more specific killing capability against naturally expressed MSLN­HCC70 and artificially MSLN­overexpressing MDA­MB­231 compared with parental MDA­MB­231 in both two dimensional (2D)­ and 3D­culture systems. In conclusion, the results demonstrated the efficacy of MSLN­SmartDC to promote MSLN­specific T cells response against TNBC and RPS3 can enhance the cytolytic activity of these T cells providing an alternative treatment approach for patients with TNBC.