Oncotarget最新文献

Modern cancer management comprises a variety of treatment strategies. Immunotherapy, while successful at treating many cancer subtypes, is often hindered by tumor immune evasion and T cell exhaustion as a result of an immunosuppressive tumor microenvironment (TME). In solid malignancies, the extracellular matrix (ECM) embedded within the TME plays a central role in T cell recognition and cancer growth by providing structural support and regulating cell behavior. Relative to healthy tissues, tumor associated ECM signatures include increased fiber density and alignment. These and other differentiating features contributed to variation in clinically observed tumor-specific ECM configurations, collectively referred to as Tumor-Associated Collagen Signatures (TACS) 1-3. TACS is associated with disease progression and immune evasion. This review explores our current understanding of how ECM geometry influences the behaviors of both immune cells and tumor cells, which in turn impacts treatment efficacy and cancer evolutionary progression. We discuss the effects of ECM remodeling on cancer cells and T cell behavior and review recent in silico models of cancer-immune interactions.

Cancer dormancy followed by recurrence remains an enigma in cancer biology. Since both local and systemic recurrences are thought to emanate from dormant micrometastasis which take origin from lymphovascular tumor emboli we wondered whether the process of dormancy might initiate within lymphovascular emboli. This study combines experimental studies with a patient-derived xenograft (PDX) of inflammatory breast cancer (Mary-X) that spontaneously forms spheroids in vitro and budding lymphovascular tumor emboli in vivo with observational studies utilizing tissue microarrays (TMAs) of human breast cancers. In the experimental studies, Mary-X during both lymphovascular emboli formation in vivo and spheroidgenesis in vitro exhibited decreased proliferation, a G₀/G₁ cell cycle arrest and decreased mTOR signaling. This induction of dormancy required calpain-mediated E-cadherin proteolysis and was mediated by decreased P13K signaling, resulting in decreased mTOR activity. In observational human breast cancer studies, increased E-cadherin immunoreactivity due to increased E-cad/NTF-1 but both decreased Ki-67 and mTOR activity was observed selectively and differentially within the lymphovascular tumor emboli. Both our experimental as well as observational studies indicate that in vivo lymphovascular tumor emboli and their in vitro spheroid equivalent initiate dormancy through these pathways.

Glomus tumors (GT) are very rare mesenchymal neoplasms arising from glomus bodies, arteriovenous structures located in the dermis and involved in thermoregulation. Although most are benign, they may occasionally present malignant histological features associated with aggressive clinical behavior, metastatic spread, and poor response to conventional chemotherapy. The BRAF V600E mutation has been identified in a subset of malignant GT, highlighting a promising therapeutic target. Here, we report the impressive clinical and morpho-metabolic response of a metastatic BRAF V600E-mutated glomangiosarcoma after treatment with encorafenib and binimetinib.

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related deaths, with adenosquamous carcinoma of the pancreas (ASCP), a rare variant, representing 1-10% of cases. Standard chemotherapy trials for pancreatic cancer exclude ASCP, leaving its optimal treatment uncertain. This report describes a 68-year-old male with metastatic ASCP and a KRAS G12C mutation, progressing through multiple lines of systemic therapy, including targeted inhibition of KRAS G12C. Notably, the patient exhibited a robust response to single-agent immune checkpoint inhibition (ICI) with pembrolizumab, despite intact mismatch repair proteins. The limited success of traditional therapies in pancreatic cancer, coupled with the rarity of ASCP, presents a challenge in establishing effective treatment strategies. While KRAS G12C inhibitors demonstrated modest benefits, this case highlights the remarkable response to ICI in a patient with squamous histology. The distinct tumor microenvironment of ASCP, characterized by squamous differentiation, may contribute to this exceptional response. This underscores the need for further research and clinical trials focused on ICI in ASCP, with an ongoing multi-center phase 2 trial investigating outcomes in this specific subset.

This study presents an observational, cross-sectional analysis of 64 patients diagnosed with small cell lung cancer (SCLC) at a reference laboratory for thoracic pathology between 2022 and 2024. The primary objective was to evaluate the expression of Delta-like ligand 3 (DLL3) and other neuroendocrine markers such as Chromogranin, and Synaptophysin, utilizing both traditional immunohistochemistry and digital pathology tools. Patients were primarily older adults, with a median age of over 71, and most biopsies were obtained from lung parenchyma. Immunohistochemistry (IHC) was performed using specific monoclonal antibodies, with DLL3 showing variable expression across the samples. Notably, DLL3 was expressed in 72.3% of the cases, with varied intensities and a semi-quantitative H-score applied for more nuanced analysis. ASCL1 was expressed in 97% of cases, with the majority considered low-expressors. Only 11% had high expression. TTF-1, traditionally not a conventional marker for the diagnosis of SCLC, was positive in half of the cases, suggesting its potential as a biomarker. The study underscores the significant variability in the expression of neuroendocrine markers in SCLC, with implications for both diagnosis and potential therapeutic targeting. DLL3, particularly, shows promise as a therapeutic target due to its high expression rate in the cohort. The use of digital pathology software QuPath enhanced the accuracy and depth of analysis, allowing for detailed morphometric analysis and potentially informing more personalized treatment approaches. The findings emphasize the need for further research into the role of these markers in the management and treatment of SCLC, considering the poor prognosis and high mortality rate observed in the cohort.