Spatial mapping of the collagen distribution in human and mouse tissues by force volume atomic force microscopy

Changes in the elastic properties of living tissues during normal development and in pathological processes are often due to modifications of the collagen component of the extracellular matrix at various length scales. Force volume AFM can precisely capture the mechanical properties of biological samples with force sensitivity and spatial resolution. The integration of AFM data with data of the molecular composition contributes to understanding the interplay between tissue biochemistry, organization and function. The detection of micrometer-size, heterogeneous domains at different elastic moduli in tissue sections by AFM has remained elusive so far, due to the lack of correlations with histological, optical and biochemical assessments. In this work, force volume AFM is used to identify collagen-enriched domains, naturally present in human and mouse tissues, by their elastic modulus. Collagen identification is obtained in a robust way and affordable timescales, through an optimal design of the sample preparation method and AFM parameters for faster scan with micrometer resolution. The choice of a separate reference sample stained for collagen allows correlating elastic modulus with collagen amount and position with high statistical significance. The proposed preparation method ensures safe handling of the tissue sections guarantees the preservation of their micromechanical characteristics over time and makes it much easier to perform correlation experiments with different biomarkers independently

The Liver Pre-Metastatic Niche in Pancreatic Cancer : A Potential Opportunity for Intervention

Simple Summary Patients with pancreatic cancer have a very poor chance of long-term survival. This is usually due to advanced disease at the time of diagnosis, which commonly includes occult or clinically obvious liver metastases. Emerging evidence suggests that organs that develop metastases exhibit microscopic changes that favor metastatic growth, collectively known as "pre-metastatic niches". Such pre-metastatic niches result from various signals originating from the primary pancreatic tumor that reprogram immune and other cells in the liver and other organs, thus enabling the growth of cancer cells once they spread. In this review, we summarize the latest discoveries regarding the liver pre-metastatic niche in pancreatic cancer. We are optimistic that intensified future research will help to reveal powerful diagnostic markers and targetable therapeutic pathways, which will ultimately benefit patients. Cancer-related mortality is primarily a consequence of metastatic dissemination and associated complications. Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies and tends to metastasize early, especially in the liver. Emerging evidence suggests that organs that develop metastases exhibit microscopic changes that favor metastatic growth, collectively known as "pre-metastatic niches". By definition, a pre-metastatic niche is chronologically established before overt metastatic outgrowth, and its generation involves the release of tumor-derived secreted factors that modulate cells intrinsic to the recipient organ, as well as recruitment of additional cells from tertiary sites, such as bone marrow-all orchestrated by the primary tumor. The pre-metastatic niche is characterized by tumor-promoting inflammation with tumor-supportive and immune-suppressive features, remodeling of the extracellular matrix, angiogenic modulation and metabolic alterations that support growth of disseminated tumor cells. In this paper, we review the current state of knowledge of the hepatic pre-metastatic niche in PDAC and attempt to create a framework to guide future diagnostic and therapeutic studies.Funding Agencies|Swedish Cancer Society [21 1824 Pj 01]; Swedish Research Society Starting Grant [2021-02356]; Swedish Society for Medical Research [S21-0079]</p

Analysis of the stromal cell-derived factor 1-3 ` A gene polymorphism in pancreatic cancer

Stromal cell derived factor-1 (SDF-1), a CXC chemokine that plays an important role in the tumor growth, angiogenesis and metastasis of tumor cells, has a polymorphism at position 801 of its 3’-untranslated region, known as SDF1-3’A. The SDF1-3’A polymorphism has been investigated in various types of cancer, but no information is currently available on its role in pancreatic cancer. In this study, 80 pancreatic cancer patients and 160 normal healthy control subjects were investigated for the genotype and allelic frequencies of the SDF-1 gene using PCR-RFLP. The genotype frequencies for GG, GA and AA were 21.25, 77.5 and 1.25% in patients, and 42.5, 55 and 2.5% in healthy subjects, respectively. The A carrier group (GA+AA genotype) and the A allele were overrepresented among the patients with pancreatic cancer (p=0.015 and p=0.031, respectively). The GA+AA genotype was statistically correlated with an advanced T stage and the presence of lymph node metastasis, and displayed a clear trend towards significance in relation to the presence of distant metastatic disease (p=0.061). Only T stage was significantly related to A allele frequency (p=0.004). SDF1-3’ A allele carriers were more prevalent among cancer patients than among normal subjects. SDF1-3’ A allele carrier status may imply a higher risk of pancreatic cancer, while the presence of the A allele in pancreatic cancer patients may be related to aggressive features of this malignancy

Adoptive Immunotherapy of Epithelial Ovarian Cancer with Vγ9Vδ2 T Cells, Potentiated by Liposomal Alendronic Acid

Abstract Adoptive immunotherapy using γδ T cells harnesses their natural role in tumor immunosurveillance. The efficacy of this approach is enhanced by aminobisphosphonates such as zoledronic acid and alendronic acid, both of which promote the accumulation of stimulatory phosphoantigens in target cells. However, the inefficient and nonselective uptake of these agents by tumor cells compromises the effective clinical exploitation of this principle. To overcome this, we have encapsulated aminobisphosphonates within liposomes. Expanded Vγ9Vδ2 T cells from patients and healthy donors displayed similar phenotype and destroyed autologous and immortalized ovarian tumor cells, following earlier pulsing with either free or liposome-encapsulated aminobisphosphonates. However, liposomal zoledronic acid proved highly toxic to SCID Beige mice. By contrast, the maximum tolerated dose of liposomal alendronic acid was 150-fold higher, rendering it much more suited to in vivo use. When injected into the peritoneal cavity, free and liposomal alendronic acid were both highly effective as sensitizing agents, enabling infused γδ T cells to promote the regression of established ovarian tumors by over one order of magnitude. Importantly however, liposomal alendronic acid proved markedly superior compared with free drug following i.v. delivery, exploiting the “enhanced permeability and retention effect” to render advanced tumors susceptible to γδ T cell–mediated shrinkage. Although folate targeting of liposomes enhanced the sensitization of folate receptor–α+ ovarian tumor cells in vitro, this did not confer further therapeutic advantage in vivo. These findings support the development of an immunotherapeutic approach for ovarian and other tumors in which adoptively infused γδ T cells are targeted using liposomal alendronic acid.</jats:p

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways

Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1–/– mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS)-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF) expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis