Interplay in galectin expression predicts patient outcomes in a spatially restricted manner in PDAC.

BACKGROUND: Galectins (Gal's) are a family of carbohydrate-binding proteins that are known to support the tumour microenvironment through their immunosuppressive activity and ability to promote metastasis. As such they are attractive therapeutic targets, but little is known about the cellular expression pattern of galectins within the tumour and its neighbouring stromal microenvironment. Here we investigated the cellular expression pattern of Gals within pancreatic ductal adenocarcinoma (PDAC). METHODS: Galectin gene and protein expression were analysed by scRNAseq (n=4) and immunofluorescence imaging (n=19) in fibroblasts and epithelial cells of pancreatic biopsies from PDAC patients. Galectin surface expression was also assessed on tumour adjacent normal fibroblasts and cancer associated primary fibroblasts from PDAC biopsies using flow cytometry. RESULTS: scRNAseq revealed higher Gal-1 expression in fibroblasts and higher Gal-3 and -4 expression in epithelial cells. Both podoplanin (PDPN+, stromal/fibroblast) cells and EpCAM+ epithelial cells expressed Gal-1 protein, with highest expression seen in the stromal compartment. By contrast, significantly more Gal-3 and -4 protein was expressed in ductal cells expressing either EpCAM or PDPN, when compared to the stroma. Ductal Gal-4 cellular expression negatively correlated with ductal Gal-1, but not Gal-3 expression. Higher ductal cellular expression of Gal-1 correlated with smaller tumour size and better patient survival. CONCLUSIONS: In summary, the intricate interplay and cell-specific expression patterns of galectins within the PDAC tissue, particularly the inverse correlation between Gal-1 and Gal-4 in ducts and its significant association with patient survival, highlights the complex molecular landscape underlying PDAC and provides valuable insights for future therapeutic interventions.

Spatial determination and prognostic impact of the fibroblast transcriptome in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma has a poor clinical outcome and responses to immunotherapy are suboptimal. Stromal fibroblasts are a dominant but heterogenous population within the tumor microenvironment and therapeutic targeting of stromal subsets may have therapeutic utility. Here, we combine spatial transcriptomics and scRNA-Seq datasets to define the transcriptome of tumor-proximal and tumor-distal cancer-associated fibroblasts (CAFs) and link this to clinical outcome. Tumor-proximal fibroblasts comprise large populations of myofibroblasts, strongly expressed podoplanin, and were enriched for Wnt ligand signaling. In contrast, inflammatory CAFs were dominant within tumor-distal subsets and expressed complement components and the Wnt-inhibitor SFRP2. Poor clinical outcome was correlated with elevated HIF-1α and podoplanin expression whilst expression of inflammatory and complement genes was predictive of extended survival. These findings demonstrate the extreme transcriptional heterogeneity of CAFs and its determination by apposition to tumor. Selective targeting of tumor-proximal subsets, potentially combined with HIF-1α inhibition and immune stimulation, may offer a multi-modal therapeutic approach for this disease.

Pancreatic cancer is one of the deadliest and most difficult cancers to treat. It responds poorly to immunotherapy for instance, despite this approach often succeeding in enlisting immune cells to fight tumours in other organs. This may be due, in part, to a type of cell called fibroblasts. Not only do these wrap pancreatic tumours in a dense, protective layer, they also foster complex relationships with the cancerous cells: some fibroblasts may fuel tumour growth, while other may help to contain its spread. These different roles may be linked to spatial location, with fibroblasts adopting different profiles depending on their proximity with cancer calls. For example, certain fibroblasts close to the tumour resemble the myofibroblasts present in healing wounds, while those at the periphery show signs of being involved in inflammation. Being able to specifically eliminate pro-cancer fibroblasts requires a better understanding of the factors that shape the role of these cells, and how to identify them. To examine this problem, Croft et al. relied on tumour samples obtained from pancreatic cancer patients. They mapped out the location of individual fibroblasts in the vicinity of the tumour and analysed their gene activity. These experiments helped to reveal the characteristics of different populations of fibroblasts. For example, they showed that the myofibroblast-like cells closest to the tumour exhibited signs of oxygen deprivation; they also produced podoplanin, a protein known to promote cancer progression. In contrast, cells further from the cancer produced more immune-related proteins. Combining these data with information obtained from patients' clinical records, Croft et al. found that samples from individuals with worse survival outcomes often featured higher levels of podoplanin and hypoxia. Inflammatory markers, however, were more likely to be present in individuals with good outcomes. Overall, these findings could help to develop ways to selectively target fibroblasts that support the growth of pancreatic cancer. Weakening these cells could in turn make the tumour accessible to immune cells, and more vulnerable to immunotherapies.

Characterization of the Immune Microenvironment in Inflammatory Breast Cancer Using Multiplex Immunofluorescence.

INTRODUCTION: Inflammatory breast cancer (IBC) is an aggressive form of breast cancer with a poorly characterized immune microenvironment. METHODS: We used a five-colour multiplex immunofluorescence panel, including CD68, CD4, CD8, CD20, and FOXP3 for immune microenvironment profiling in 93 treatment-naïve IBC samples. RESULTS: Lower grade tumours were characterized by decreased CD4+ cells but increased accumulation of FOXP3+ cells. Increased CD20+ cells correlated with better response to neoadjuvant chemotherapy and increased CD4+ cells infiltration correlated with better overall survival. Pairwise analysis revealed that both ER+ and triple-negative breast cancer were characterized by co-infiltration of CD20 + cells with CD68+ and CD4+ cells, whereas co-infiltration of CD8+ and CD68+ cells was only observed in HER2+ IBC. Co-infiltration of CD20+, CD8+, CD4+, and FOXP3+ cells, and co-existence of CD68+ with FOXP3+ cells correlated with better therapeutic responses, while resistant tumours were characterized by co-accumulation of CD4+, CD8+, FOXP3+, and CD68+ cells and co-expression of CD68+ and CD20+ cells. In a Cox regression model, response to therapy was the most significant factor associated with improved patient survival. CONCLUSION: Those results reveal a complex unique pattern of distribution of immune cell subtypes in IBC and provide an important basis for detailed characterization of molecular pathways that govern the formation of IBC immune landscape and potential for immunotherapy.

The Chemotherapy Response Score (CRS): Interobserver Reproducibility in a Simple and Prognostically Relevant System for Reporting the Histologic Response to Neoadjuvant Chemotherapy in Tuboovarian High-grade Serous Carcinoma.

A 3-tier histopathologic scoring system, the chemotherapy response score (CRS), was previously devised for reporting the histologic response to neoadjuvant chemotherapy in interval debulking surgery specimens of stage IIIc/IV tuboovarian high-grade serous carcinoma. This has been shown to predict the outcome and offer additional information to other methods of assessing the treatment response. In the present study, the reproducibility of this scoring system was assessed by determining the interobserver agreement among reporting pathologists. A total of 5 groups each comprising 3 pathologists with different levels of expertise were selected. The participants underwent an online tutorial on how to apply the CRS system. 40 cases (38 cases in 2 appraiser groups) were scored individually by each of the 15 pathologists. The interobserver reproducibility was calculated using Fleiss' κ, Kendall's coefficient of concordance, and the absolute agreement between (a) individual pathologists within 1 group, (b) with the majority score agreement between all groups, and (c) with all individual scores. The CRS system was found to be highly reproducible among all the pathologists' groups (κ=0.761). The agreement in identifying the group of patients with the best response to chemotherapy was exceptionally high (κ=0.926). We conclude that CRS has a high interobserver reproducibility, especially in identifying the subgroup of patients with the best chemotherapy response, justifying its inclusion in clinical trials and reporting practice.

Growing Teratoma Syndrome: A Report of 2 Cases and Review of the Literature.

We report 2 cases of growing teratoma syndrome (GTS) in patients who had been treated with surgery and chemotherapy for immature ovarian teratoma. One of the patients presented with probable paraneoplastic encephalitis. Resection of "recurrences" in both patients showed deposits of mature teratoma and extensive gliomatosis peritonei. It is important for both pathologists and clinicians to be aware of this uncommon entity to avoid misdiagnosis of GTS as recurrence of immature teratoma and disease progression, and to avert unnecessary continuation of chemotherapy. GTS may occur several years after diagnosis of the primary tumor, and rarely develop in treated patients who have become pregnant. Surgical debulking is the optimal modality of treatment as GTS is not chemosensitive. If surgical debulking of GTS is incomplete, long-term follow-up with imaging is required to avoid complications such as bowel obstruction and the sequelae of pressure effects (such as vascular thrombosis, fistula formation, etc.) from bulky deposits of mature teratoma/GTS and gliomatosis peritonei.

Endometrial biopsy in women with abnormal uterine bleeding: inadequate and unassessable categorisation is not clinically relevant.

AIMS: Inadequate endometrial biopsy comprises a dilemma for gynaecologists and histopathologists alike. This study was conducted to assess the clinical merit of classifying scant endometrial biopsy into inadequate and unassessable using McCluggage criteria. METHODS: We retrospectively classified 268 endometrial biopsies, initially reported as inadequate, into inadequate (n=74) and unassessable (n=174) using McCluggage criteria after excluding 20 cases; all taken from patients aged ≥50 years with abnormal uterine bleeding attending Sandwell and West Birmingham Hospitals, UK from 1 January 2007 until 30 September 2012. The electronic clinical records were reviewed to find out the consequent clinical decisions and final outcomes. The follow-up period was 15 months after including the last patient. RESULTS: The median age was 57 years (range: 50-97), and the median number of visits to hospital till the diagnosis was achieved was 2 (range: 1-4). The final diagnosis of endometrial hyperplasia or cancer was reported in 9 cases; 5 (7.1%) with an initial finding of inadequate and 4 with unassessable (2.4%); the difference was statistically insignificant (p=0.13). More patients in the inadequate category (82.4%) underwent further investigations when compared with the unassessable category (68.4%); the difference was statistically significant (p=0.029). There was no statistically significant difference in the inadequate to unassessable ratio when the endometrial thickness was ≥5 mm or <5 mm within the Pipelle group (p=0.46) or the curettage group (p=0.34). CONCLUSIONS: Our findings suggest that categorising scant endometrial specimens into inadequate or unassessable has no clinical implications. The gynaecologist should interpret the histopathology report in the light of clinical scenario.

Glomus tumor of the mediastinum.

Glomus tumors are rare benign myoepithelial neoplasms that can present with intractable pain. We report the case of a 59-year-old gentleman who presented with upper abdominal and chest pain caused by a posterior mediastinal glomus tumor arising from the spinal column, which required surgical resection. As glomus tumors usually develop in the limbs, this case highlights the complexity of diagnosis and treatment of glomus tumors when they present in rare locations.

An unusual presentation of giant cell arteritis.

Giant cell arteritis (GCA) is a chronic vasculitis that typically presents with headache, fever and polymyalgia although atypical presentations are known. We present a case of GCA with nonproductive cough and pyrexia of unknown origin emphasizing this atypical nature of presentation. We report a rare association of GCA with granulomatous hepatitis. We also support the use of PET scanning in diagnosing and monitoring this condition.