Search Results (2,742)

Human epidermal growth factor receptor 2 (HER2) dysregulation contributes to tumorigenesis in gastric and gastroesophageal junction adenocarcinomas (GC/GEJ). HER2 overexpression has been associated in multiple cohorts with aggressive behavior and poor outcomes. While HER2 amplification has long guided therapy in HER2-positive disease, antibody–drug conjugates (ADCs) have shifted attention toward the HER2-low category, typically defined as immunohistochemistry (IHC) 1+ or IHC 2+ with negative in situ hybridization (ISH). This narrative review integrates evidence from the peer-reviewed literature, current testing recommendations, and registered clinical trials. It clarifies practical issues in HER2-low assessment and maps the evolving therapeutic landscape of HER2-targeted ADCs including rational combination strategies that may extend benefit beyond conventionally HER2-positive tumors. A cross-tumor perspective contrasts GC/GEJ testing and biology with the breast cancer paradigm and summarizes the importance of HER2-low expression in non-gastric malignancies. Finally, we discuss the therapeutic strategies in HER2-low GC/GEJ and highlight key safety and monitoring considerations for HER2-directed ADCs. Full article

Background/Objectives: Trastuzumab emtansine (T-DM1) is widely used in Human Epidermal Growth Factor Receptor2 (HER2)-positive metastatic breast cancer; however, outcomes vary, and reliable prognostic markers remain limited. We developed the CALA index as a composite biomarker integrating CA15-3, lactate dehydrogenase (LDH), and albumin. This study aimed to evaluate the prognostic value of the CALA index in metastatic breast cancer treated with T-DM1. Methods: This multicenter retrospective study included 168 patients treated with T-DM1 across four tertiary centers. The CALA index was calculated using pretreatment levels of CA15-3, LDH, and albumin. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff value, and patients were stratified into groups accordingly. Survival outcomes and independent risk factors were assessed using Kaplan–Meier and Cox regression analyses. Results: The median overall survival (OS) was 26 months (95% CI: 21.3–30.7). ROC analysis identified an optimal CALA cutoff value of 118.3. Patients with CALA ≤ 118.3 demonstrated significantly longer OS compared with those with CALA > 118.3 (log-rank p = 0.006), with 1- and 3-year OS rates of 81.2% and 43.2% versus 69.8% and 22.7%, respectively. In univariate analysis, CALA > 118.3 was associated with worse OS (HR: 1.699; 95% CI: 1.151–2.506; p = 0.008), and this association remained significant in multivariate analysis (HR: 1.671; 95% CI: 1.088–2.565; p = 0.019). Conclusions: The CALA index was associated with overall survival in metastatic breast cancer treated with trastuzumab emtansine and may serve as a practical tool for risk stratification. Full article

Background: Human epidermal growth factor receptor 2 (HER2) alterations have been implicated as mechanisms of resistance to anti-epidermal growth factor receptor (anti-EGFR) therapy in metastatic colorectal cancer (mCRC). We aimed to evaluate the predictive and prognostic significance of HER2 expression in patients with RAS wild-type mCRC in a real-world setting. Methods: We conducted a multicenter retrospective cohort study across ten oncology centers in Turkey, including patients with RAS wild-type mCRC treated between 2015 and 2022. Clinical outcomes, including progression-free survival (PFS) and overall survival (OS), were compared between HER2-positive and HER2-negative groups. Multivariable Cox proportional hazards models were used to identify independent predictors of survival outcomes. Results: Among 204 patients, 28 (13.7%) were HER2-positive. Baseline characteristics were generally comparable; however, HER2-positive patients showed a trend toward higher-grade tumors and were significantly less likely to receive anti-EGFR therapy. HER2-positive patients had significantly shorter PFS compared to HER2-negative patients (median 10 vs. 13 months; p = 0.006). In multivariable analysis, HER2 positivity remained an independent predictor of shorter PFS (HR 1.76, 95% CI 1.01–3.07; p = 0.045). In the subgroup of 144 patients receiving anti-EGFR therapy, HER2-positive patients also demonstrated significantly shorter PFS (median 9.0 vs. 14.0 months; p = 0.023). No significant differences in OS were observed between groups. Conclusions: HER2 positivity is associated with reduced response to anti-EGFR therapy and independently predicts shorter PFS in patients with RAS wild-type mCRC. These findings further support the role of HER2 as a clinically relevant biomarker in RAS wild-type mCRC, particularly in predicting response to anti-EGFR therapy, while highlighting the need for optimized patient selection strategies in the era of HER2-targeted treatments. Full article

Triple-negative breast cancer is an aggressive and heterogeneous type of invasive breast cancer (BC) in which the cancer cells lack estrogen and progesterone receptors, as well as expression of the human epidermal growth factor 2 protein. This cancer tends to grow and spread faster than other BC subtypes, and is associated with a poor prognosis due to early visceral and neurological recurrences. Multidisciplinary management includes surgery, chemotherapy, radiation therapy, and immunotherapy with targeted immune checkpoint inhibitors (ICIs). The introduction of ICIs has improved outcomes in patients with TNBC, particularly in the metastatic and neoadjuvant settings. Despite these advances, a significant proportion of patients either do not respond to treatment or develop resistance to it. TNBC mortality remains high, underscoring the urgent need to identify novel prognostic and predictive biomarkers to overcome resistance to immunotherapy. Following a brief overview of the clinical features and established biomarkers of TNBC, the current review focuses on immune checkpoint proteins (ICPs) beyond PD-1 and PD-L1, and on the potential use of soluble ICPs rather than the well-established membrane-bound assays. These soluble ICPs are produced through the alternative splicing of messenger (m)RNA or the cleavage/shedding of membrane-bound proteins. This is followed by an overview of current treatment and novel predictive targets in TNBC. Additionally, the involvement of the B- and T-lymphocyte attenuator (BTLA)/herpes virus entry mediator (HVEM)/CD160 pathway and its role in the pathogenesis of BC and TNBC are reviewed, highlighting the potential use of BTLA and HVEM as biomarkers. Full article

Background: Abemaciclib (ABM) in combination with tamoxifen (TAM) is an extremely significant treatment regimen for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. It is approved for patients to reduce the risk of cancer recurrence. A bioanalytical method for the simultaneous determination of this new anti-breast cancer combination and its pharmacokinetic application has not yet been reported. Methods: An ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) method was developed for quantifying ABM, TAM, and its metabolites, including abemaciclib active metabolites M2, M18, and M20 and tamoxifen active metabolite N-desmethyl tamoxifen (NDTAM), in rat plasma using econazole as the internal standard (IS). Chromatographic separation was achieved on a Kinetex C18 column (100 × 2.1 mm ID, 2.6 µm) using gradient elution with 5 mM ammonium formate in water (eluent A) and 5 mM ammonium formate in water/methanol (1:9, v/v, eluent B) at a flow rate of 0.4 mL/min. Detection was performed on a TSQ Fortis Plus mass spectrometer employing multiple reaction monitoring mode under positive electrospray ionization. Results: The developed method was validated according to the guidance of the FDA. Linearity in rat plasma (ng/mL) was achieved from 1 to 1000 for ABM, TAM, and M20; 3 to 1000 for M2; 5 to 500 for M18; and 1 to 500 for NDTAM; with correlation coefficients ranging from 0.9991 to 0.9931 for all analytes using a weighting factor of 1/X². The lower limit of detection (LLOD) ranged between 0.3 and 1.5 ng/mL for all drugs. The accuracy ranged from 96 to 108% and the precision was less than 7.6% RSD for all analytes. For the first time, the newly developed approach was effectively used in a pharmacokinetic study on the simultaneous oral administration of ABM and TAM in rats that received 30.0 mg/kg of ABM and 8.0 mg/kg of TAM. Conclusions: To the best of our knowledge, this is the first reported UPLC–MS/MS method for the assay of ABM, TAM, and its active metabolites in plasma. This method offers a bioanalytical tool for assessing the pharmacokinetics of ABM and TAM. Therefore, this study makes a definite significant contribution to the field of bioanalytical research. Further validation in human plasma is required for future clinical or therapeutic drug monitoring applications, as the approach was developed in an animal model. Full article

Compound repurposing is an efficient method to save both time and costs by redirecting previously synthesized small molecules towards new biological targets. In this research, we employ computational methodologies to investigate and assess target engagement of small molecules as tyrosine kinase inhibitors (TKIs). Therefore, compounds TKI.2a, TKI.2b, TKI.6, TKI.16, TKI.19, and TKI.21b identified from our earlier research, undergo assessments of molecular similarity, docking studies, and pharmacophore modeling along with those discovered through database searches. Compounds TKI.2a, TKI.2b, TKI.6, and TKI.19 appear to exhibit multi-target tyrosine kinase inhibitory activities against VEGFR-2 (Vascular Endothelial Growth Factor Receptor), RET (proto-oncogene tyrosine–protein kinase receptor), PDGFRα (Platelet-Derived Growth Factor Receptor alpha), EGFR (Epidermal Growth Factor Receptor), and HER2 (Human Epidermal Receptor) receptors. Pharmacophore models were applied for ligand-based virtual screening using defined parameters to discover candidate compounds that exhibit drug-likeness with FDA (Food and Drug Administration)-approved tyrosine kinase inhibitors. Molecular docking studies identified lead compounds for each biological target based on their overall affinity values and established interactions. Compound ChEMBL2170947 was found to be the most promising candidate for the VEGFR-2 receptor, ChEMBL5019511 for PDGFRα, ChEMBL2216869 for EGFR, and ChEMBL3355044 for HER2. Full article

Background/Objectives: The prognostic significance of the uric acid-to-albumin ratio (UAR) in patients with hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2−) metastatic breast cancer treated with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors has not been adequately investigated. This study aimed to investigate the association between baseline UAR and survival outcomes in this patient population. Methods: This retrospective study included HR-positive/HER2-negative metastatic breast cancer patients treated with ribociclib or palbociclib at Necmettin Erbakan University between May 2020 and April 2025. UAR was calculated by dividing the serum uric acid level (mg/dL) by the serum albumin level (g/dL). Based on receiver operating characteristic (ROC) analysis, the optimal cut-off value for UAR was identified as 1.0 (AUC = 0.67; sensitivity 68%; specificity 58%). Patients were subsequently classified into two groups as UAR < 1 and UAR ≥ 1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method and compared with the log-rank test. Independent prognostic factors were evaluated using Cox regression analyses. Results: A total of 118 eligible patients were included in the analysis, including 34 (28.8%) in the UAR < 1 group and 84 (71.2%) in the UAR ≥ 1 group. The proportion of postmenopausal patients was significantly higher in the UAR ≥ 1 group (p = 0.01). Kaplan–Meier analysis showed that median PFS was not reached in the UAR < 1 group, whereas it was 33.05 months in the UAR ≥ 1 group (log-rank p = 0.06). Median OS was not reached in the UAR < 1 group and was 50.7 months in the UAR ≥ 1 group (p = 0.017). Multivariate Cox regression analysis demonstrated that UAR < 1 was associated with improved PFS (HR = 0.65; 95% CI: 0.34–0.89; p = 0.04). Postmenopausal status emerged as an independent adverse prognostic factor for PFS (HR = 1.92; 95% CI: 1.10–4.05; p = 0.04). In addition, UAR < 1 was associated with a reduced risk of mortality in the OS analysis (HR = 0.61; 95% CI: 0.26–0.87; p = 0.01). Conclusions: Lower baseline UAR was associated with more favorable survival outcomes in HR-positive/HER2-negative metastatic breast cancer patients treated with CDK4/6 inhibitors. As an inexpensive and easily accessible biomarker derived from routine laboratory parameters, UAR may provide additional prognostic information for clinical risk stratification. Full article

Polydeoxyribonucleotide (PDRN) activates the adenosine A2A receptor (A2AR), triggering anti-inflammatory signaling and providing essential nucleotides for the salvage pathway, thereby helping bypass metabolic bottlenecks and promoting tissue repair. Combining PDRN with biochemical agents and physical stimuli represents a significant shift in medical treatment, moving from monotherapy to an integrated, multi-target regenerative approach. These combinatorial strategies effectively address the limitations of PDRN, such as its rapid degradation and diffusion, by simultaneously meeting the structural, metabolic, and signaling needs of injured tissues. The mechanism of action for PDRN involves a synergistic effect with hyaluronic acid, amplification of growth factors (e.g., Platelet-Rich Plasma (PRP), Epidermal Growth Factor (EGF), Platelet-Derived Growth Factor (PDGF)), and enhancements from extracorporeal shockwave therapy (ESWT) and lasers. This results in a notable acceleration of the repair process for chronic wounds, musculoskeletal disorders, and neurological injuries. As intelligent delivery systems like responsive hydrogels and sustainable L-PDRN production continue to advance, these synergistic protocols are poised to redefine global standards of care in regenerative medicine and esthetic dermatology. Future clinical success will hinge on the standardization of sequence-specific protocols and large-scale validation to ensure long-term safety and efficacy. Full article

Background: Evaluation of gene-level copy number variants (CNVs) for diagnosis and therapeutic decision making has become standard of care with next-generation sequencing (NGS), immunohistochemistry (IHC), and/or fluorescence in situ hybridization (FISH) being used to detect gene amplifications/deletions in tumor tissue. In contrast to most solid tumors, CNS cancers are challenging to evaluate by resection and/or biopsy due to the associated risks with invasive brain surgery that can also result in death or associated morbidity and therefore alternate methods are required.Methods: This study presents the analytical validation of using quantitative PCR (qPCR) to detect gene CNVs directly from cerebrospinal fluid (CSF)-derived DNA and from the Ascent^TM low-pass whole genome sequencing (LP-WGS) libraries, demonstrating concordance with the gold standard of NGS/IHC/FISH used in tumor tissue. Results: The analytical sensitivity of qPCR to detect gene amplification calls for ERBB2 (erb-b2 receptor tyrosine kinase 2) was demonstrated to be 100% and that of EGFR (epidermal growth factor receptor) was 83%, with specificities of 96% and 100%, respectively. The analytical sensitivity of qPCR to detect gene deletions for CDKN2A/2B (cyclin-dependent kinase inhibitor 2A/2B) was 60% and that for MTAP (methylthioadenosine phosphorylase) was 100% with a specificity of 100% for all three genes. Ascent^TM was demonstrated to have a higher sensitivity (100%) when compared to qPCR for the same genes evaluated and demonstrated 100% positive agreement and 100% negative agreement with known CNV status. Conclusions: The results demonstrate that given the paucity of cells in CSF limiting the use of IHC and FISH, qPCR and Ascent^TM provide highly sensitive, novel, minimally invasive methods for the evaluation of gene copy number (CN) status to inform the diagnosis and management of CNS cancers. Full article

Cost-effective, fluorescence-based biodiagnostic devices have the potential to expand point-of-care (POC) testing in resource-limited settings, thereby creating new opportunities for accessible and decentralised diagnostics. The objective of this study is to investigate the performance of a newly designed and simplified system that uses several cost-effective sensors for use in a fluorescence-based biodiagnostic setup. A collecting setup that includes an elliptical mirror to focus emitted fluorescence onto the semiconductor sensors was designed for an intensity-based readout. The readout was realised by various photodiodes, photoresistors, phototransistors and one multi-pixel photon counter (MPPC). Over a range of fluorophore concentrations using serial dilutions of Rhodamine B (RhB), the limit of detection (LOD) and limit of quantification (LOQ) at system level were evaluated. With the exception of the photodiodes, the system demonstrated promising performance with all sensors. The system using the photoresistors achieved the lowest LOD but showed limited repeatability, while the system using the MPPC and phototransistors exhibited high repeatability. A proof-of-concept demonstrated the feasibility of a photoresistor-based configuration by using a sandwich immunoassay for the detection of the antigen Human Epidermal growth factor Receptor 2 (HER2) (100 nM). While this study has not yet encompassed the full spectrum of clinically relevant concentrations, it has yielded valuable insights to enable further enhancements, without the necessity for highly specialised or costly equipment. The limitations and necessary improvements for further developments are discussed. Full article

Background and Objectives: This study aimed to evaluate the association between systemic nicotine administration and histological and biochemical repair endpoints in an acetic acid-induced rat oral ulcer model. Materials and Methods: Thirty-six male Wistar rats were assigned to control, oral ulcer + saline, and oral ulcer + nicotine (1 mg/kg/day, s.c.) groups. Oral ulcers were induced with 70% acetic acid. After 15 days, buccal mucosa and plasma samples were collected for histopathological and biochemical analyses. Epithelial thickness and fibrosis were assessed histologically, while malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), vascular endothelial growth factor-A (VEGF-A), and epidermal growth factor receptor (EGFR) were quantified. Results: Relative to controls, ulcer induction was associated with reduced epithelial thickness and increased fibrosis, MDA, and TNF-α levels. Compared with the oral ulcer + saline group, the nicotine-treated group showed greater epithelial thickness, lower fibrosis, lower MDA and TNF-α levels, and higher VEGF-A and EGFR levels at the study endpoint. No significant difference in VEGF-A was observed between the control and oral ulcer + saline groups. Conclusions: In this acetic acid-induced rat model, systemic nicotine administration was associated with improved endpoint histological and biochemical indices of oral ulcer repair. Because macroscopic wound closure, dose–response relationships, route comparisons, and direct mechanistic experiments were not included, these findings should be interpreted as preliminary preclinical associations rather than evidence of a direct causal effect of nicotine on wound healing. Full article

Background/Objectives: Triptolide (TP), a potent natural diterpenoid, exhibits anti-glioma activity, but faces significant clinical translation challenges, including poor water solubility, systemic toxicity such as hepatotoxicity, and inadequate tumor targeting. This study aimed to develop a novel epidermal growth factor receptor (EGFR)-targeted liposomal formula-tion, designated as TP-CTX-Lip (where CTX denotes cetuximab), to enhance the deliv-ery efficiency and therapeutic window of TP. Methods: The formulation was optimized using a uniform design approach (four factors, six levels) and prepared via thin-film hydra-tion–ultrasonication. The encapsulation of TP was supported by Fourier transform in-frared spectroscopy (FTIR) and thermal analysis (DSC/TGA), which revealed molecu-lar interactions (e.g., hydrogen bonding) with lipid components and a marked en-hancement in thermal stability, consistent with successful incorporation into the lipo-somal bilayer. The physicochemical properties, including the size, polydispersity index (PDI), zeta potential, encapsulation efficiency, and drug loading, were characterized. In vitro release kinetics were evaluated in phosphate buffer (pH 7.4), and cytotoxicity was assessed in high-EGFR (U87-MG) and low-EGFR (SW1088) glioma cells. In vivo efficacy and developmental toxicity were investigated using zebrafish models. The op-timized TP-CTX-Lip demonstrated favorable characteristics: size = 131.3 ± 4.5 nm, PDI = 0.24 ± 0.006, zeta potential = −23.37 ± 0.27 mV, encapsulation efficiency = 85.83% ± 1.81%, and drug loading = 13%. In vitro release followed first-order kinetics dominated by Higuchi diffusion (79.0% ± 4% at 24 h). After 48 h of treatment, TP-CTX-Lip exhib-ited significantly enhanced cytotoxicity in U87-MG cells (IC50 = 10.4 ± 0.2 nM), com-pared with IC50 values of 42.8 nM in SW1088 cells and 45.3 nM for non-targeted lipo-somes. In the 3T3-L1 non-cancerous cell line, the 48 h IC50 value of TP-CTX-Lip (8.433 ± 0.954µM) was higher than that of the TP solution (2.173 ± 0.181µM) but lower than that of TP-Lip (25.78 ± 2.691µM). Specifically, in 3T3-L1 cells, the 48 h IC50 of TP-CTX-Lip (8.43 µM) was approximately 4-fold higher than that of free TP (2.17 µM), confirming its substantially reduced cytotoxicity against non-cancerous cells. Results: In comparison to TP-Lip and free FITC solution, the uptake rate of TP-CTX-Lip in U87-MG cells exhibited a significantly higher level. Specifically, the uptake rate for the TP-CTX-Lip group (57.46 ± 5.44%) was statistically significantly higher than that of TP-Lip (13.7 ± 2.33%) and the free FITC solution group (20.97 ± 1.60%) (p < 0.01). In zebrafish, TP-CTX-Lip reduced developmental toxicity, with LC50 increased 1.26 times to 5.733 μg/mL, and suppressed orthotopic U87-MG xenograft growth (p < 0.001), in-dicating an improved therapeutic window as reflected by the LC50/IC50 ratio. Conclusions: the EGFR-targeted TP-CTX-Lip significantly enhances the tumor selectivity and safety of TP, providing a promising strategy for targeted glioma therapy. Full article

The biologic and prognostic value of tumor human epidermal growth factor receptor 2 (HER2) expression in patients with advanced urothelial carcinoma (UC) who undergo systemic therapies remains controversial. A systematic search of English-language literature using PubMed, Scopus, and Cochrane Library was performed in October 2025 according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) protocol to evaluate the prognostic value of tumor HER2 expression in predicting oncological outcomes of patients with advanced UC. The primary endpoints were recurrence-free survival (RFS), progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS). Seventeen studies comprising 4909 patients were eligible. HER2 expression was significantly associated with inferior RFS (HR 1.68, 95% CI 1.16–2.42; p = 0.005) and CSS (HR 1.36, 95% CI 1.10–1.68; p = 0.004), but not with OS (HR 1.03, 95% CI 0.54–1.80) or PFS (HR 0.97, 95% CI 0.50–1.89), in patients with advanced UC. In conclusion, tumor HER2 expression may identify a subgroup of patients with advanced UC at increased risk of recurrence and cancer-specific mortality, supporting its potential role as a prognostic biomarker. However, standardized assessment and prospective studies are warranted to define its utility for risk stratification and therapeutic targeting. Full article

Background: Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related mortality despite major advances in diagnostics and therapies. The prognosis remains poor, mostly due to late-stage presentation and molecular heterogeneity. Epidermal growth factor receptor (EGFR) mutations are common drivers of NSCLC. The development of EGFR tyrosine kinase inhibitors (TKIs) has significantly improved outcomes in patients with EGFR mutations. Variant allele frequency (VAF) is a quantitative genomic measure representing the proportion of sequencing reads harboring a given mutation. In NSCLC tissue, the EGFR mutation VAF reflects tumor clonality and intratumoral heterogeneity, and accumulating evidence suggests an association between EGFR VAF and response to EGFR-targeted TKIs. Methods: To address the limited synthesis of data on the relevance of EGFR mutation VAF in NSCLC, we conducted a narrative review of the literature using PubMed/MEDLINE and Embase databases and current clinical guidelines, synthesizing available evidence on EGFR VAF, including its biological, molecular, and therapeutic implications in EGFR-mutated disease. The review was structured in accordance with the SANRA (Scale for the Assessment of Narrative Review Articles) checklist. Results: EGFR VAF and on-treatment VAF dynamics are consistently associated with treatment response, progression-free survival, and overall survival in osimertinib-treated NSCLC. Baseline VAF enables risk stratification, early clearance kinetics predict durable benefit, and longitudinal VAF monitoring facilitates early detection of resistance. Importantly, the prognostic implications of VAF differ fundamentally between tissue-based and plasma-based measurements: high tissue VAF reflects clonal homogeneity and predicts favorable TKI response, whereas high plasma VAF indicates elevated tumor burden and is associated with inferior outcomes. In the second-line setting, the T790M/activating mutation ratio serves as a surrogate for resistance clonality and independently predicts osimertinib efficacy. Conclusions: EGFR VAF represents a promising dynamic molecular biomarker for treatment monitoring and precision decision-making in EGFR-mutated NSCLC. Full article