mRNA Subtype of Cancer-Associated Fibroblasts Significantly Affects Key Characteristics of Head and Neck Cancer Cells

Head and neck squamous cell carcinomas (HNSCC) belong among severe and highly complex malignant diseases showing a high level of heterogeneity and consequently also a variance in therapeutic response, regardless of clinical stage. Our study implies that the progression of HNSCC may be supported by cancer-associated fibroblasts (CAFs) in the tumour microenvironment (TME) and the heterogeneity of this disease may lie in the level of cooperation between CAFs and epithelial cancer cells, as communication between CAFs and epithelial cancer cells seems to be a key factor for the sustained growth of the tumour mass. In this study, we investigated how CAFs derived from tumours of different mRNA subtypes influence the proliferation of cancer cells and their metabolic and biomechanical reprogramming. We also investigated the clinicopathological significance of the expression of these metabolism-related genes in tissue samples of HNSCC patients to identify a possible gene signature typical for HNSCC progression. We found that the right kind of cooperation between cancer cells and CAFs is needed for tumour growth and progression, and only specific mRNA subtypes can support the growth of primary cancer cells or metastases. Specifically, during coculture, cancer cell colony supporting effect and effect of CAFs on cell stiffness of cancer cells are driven by the mRNA subtype of the tumour from which the CAFs are derived. The degree of colony-forming support is reflected in cancer cell glycolysis levels and lactate shuttle-related transporters

Inhibition of Transglutaminase 2 activity increases cisplatin cytotoxicity in a model of human hepatocarcinoma chemotherapy

Transglutaminase 2 (TG2) is a ubiquitous multifunctional enzyme whose expression has been found to be altered in numerous studies of apoptosis and cell survival; its activity has been found to be increased in many types of cancer, where it is often over-expressed. Cisplatin has long been used as an effective therapeutic drug to treat numerous cancers. Although its activity is based on cross-linking of DNA, cisplatin may also operate via other mechanisms that involve modification and alteration in the activity of protein and RNA modulators of the cell cycle and apoptotic processes; these mechanisms are less well characterised. In this study, we investigated the effects of cisplatin-induced apoptosis on TG2 expression and activity in the human hepatocarcinoma (HepG2) cell line. Through a combination of Western blotting, enzymatic activity assays, flow cytometry and fluorescence microscopy we provide evidence that TG2 is inhibited during initiation of apoptosis by cisplatin, an observation that was reversed by increasing the expression of TG2, by treating cells with retinoic acid. We also report, for the first time, that cisplatin can directly inhibit transglutaminase activity in vitro. Collectively, these studies increase our understanding of the mechanism(s) of action of cisplatin, as cisplatin–mediated reduction in TG2 activity appears to act as an early activator of apoptosis during chemotherapeutic treatment of hepatocarcinoma cells. This observation suggests an explanation as to how increased levels of TG2 activity in cancer cells could contribute to chemotherapeutic resistance to cisplatin, and so has implications for novel approaches to cisplatin therap

Quantitative Morphology of Cerebral Thrombi Related to Intravital Contraction and Clinical Features of Ischemic Stroke

© 2020 Lippincott Williams and Wilkins. All rights reserved. Background and Purpose: The purpose was to assess quantitatively and qualitatively the composition and structure of cerebral thrombi and correlate them with the signs of intravital clot contraction (retraction), as well as with etiology, severity, duration, and outcomes of acute ischemic stroke. Methods: We quantified high-resolution scanning electron micrographs of 41 cerebral thrombi for their detailed cellular and noncellular composition and analyzed histological images for the overall structure with the emphasis on red blood cell compression, fibrin age, and the signs of inflammation. Results: Cerebral thrombi were quite compact and had extremely low porosity. The prevailing cell type was polyhedral compressed erythrocytes (polyhedrocytes) in the core, and fibrin-platelet aggregates were concentrated at the periphery; both findings are indicative of intravital contraction of the thrombi. The content of polyhedrocytes directly correlated with the stroke severity. The prevalence of fibrin bundles was typical for more severe cases, while the content of fibrin sponge prevailed in cases with a more favorable course. The overall platelet content in cerebral thrombi was surprisingly small, while the higher content of platelet aggregates was a marker of stroke severity. Fibrillar types of fibrin prevailed in atherothrombogenic thrombi. Older fibrin prevailed in thrombi from the patients who received thrombolytics, and younger fibrin dominated in cardioembolic thrombi. Alternating layers of erythrocytes and fibrin mixed with platelets were common for thrombi from the patients with more favorable outcomes. Thrombi with a higher number of leukocytes were associated with fatal cases. Conclusions: Most cerebral thrombi undergo intravital clot contraction (retraction) that may be of underestimated clinical importance. Despite the high variability of the composition and structure of cerebral thrombi, the content of certain types of blood cells and fibrin structures combined with the morphological signs of intravital contraction correlate with the clinical course and outcomes of acute ischemic stroke

Long-term treatment with rilzabrutinib in patients with immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease associated with autoantibodymediated platelet destruction and impaired platelet production, resulting in thrombocytopenia and a predisposition to bleeding. The ongoing, global phase 1/2 study showed that rilzabrutinib, a Bruton tyrosine kinase inhibitor specifically developed to treat autoimmune disorders, could be an efficacious and well-tolerated treatment for ITP. Clinical activity, durability of response, and safety were evaluated in 16 responding patients who continued rilzabrutinib 400 mg twice daily in the long-term extension (LTE) study. At LTE entry, the median platelet count was 87 × 109/L in all patients, 68 × 109/L in those who had rilzabrutinib monotherapy (n = 5), and 156 × 109/L in patients who received concomitant ITP medication (thrombopoietin-receptor agonists and/or corticosteroids, n = 11). At a median duration of treatment of 478 days (range, 303-764), 11 of 16 patients (69%) continued to receive rilzabrutinib. A platelet count of =50 × 109/L was reported in 93% of patients for more than half of their monthly visits. The median percentage of LTE weeks with platelet counts =30 × 109/L and =50 × 109/L was 100% and 88%, respectively. Five patients discontinued concomitant ITP therapy and maintained median platelet counts of 106 × 109/L at 3 to 6 months after stopping concomitant ITP therapy. Adverse events related to treatment were grade 1 or 2 and transient, with no bleeding, thrombotic, or serious adverse events. With continued rilzabrutinib treatment in the LTE, platelet responses were durable and stable over time with no new safety signals.</p

Evaluation of alpha-methylacyl-CoA racemase, metallothionein and prostate specific antigen as prostate cancer prognostic markers. Neoplasma 59: 191

Current diagnostic techniques are inefficient in distinguishing latent and low-risk forms of prostate cancer from high-risk forms. The present study is focused on determination of putative tumor markers of aggressive high-grade forms of prostate cancer. Potential markers were determined in blood sera of 133 patients (82 cases and 51 controls) and in cell lines (Gleason score 9-derived 22Rv1 and normal tissue derived PNT1A) on mRNA and protein levels. Alpha-methylacyl-CoA racemase (AMACR), metallothionein classes 1A and 2A (MT1A and MT2A) were determined and compared to prostate specific antigen (PSA) levels. On mRNA level, significantly increased expression of MT2A (2.4-fold), PSA (2.6-fold) and AMACR (8.4-fold) and insignificantly (1.9-fold) elevated MT1A in 22Rv1 compared to non-tumor PNT1A were determined. On protein level, significant enhancement of free PSA and total PSA in tumor cell line was evident. AMACR protein was 1.5-fold elevated in tumor line (below the level of significance). Contrary to mRNA, significantly (p = 0.01) reduced level of MT protein in tumor lines was determined. In the case of serum level, significantly enhanced MT level (4.5-fold) in patients&apos; sera was found. No significant changes were observed in the case of AMACR. These findings indicate possible alternative role of MT to PSA prostate cancer marker. In addition, level of AMACR is distinctly higher in the Gleason score 9 in serum of patients and MT shows a descending trend in relation to Gleason score

426. Phase I/II Ongoing Study of Rilzabrutinib, an Oral Bruton Tyrosine Kinase Inhibitor, in Immune Thrombocytopenia: Extended Follow‐up and Long‐term Analyses with Optimal Dose

Background: For most ITP patients, durable remission remains elusive and their disease becomes refractory to current treatments. Rilzabrutinib, an oral, reversible, covalent BTK inhibitor, targets mechanisms of platelet destruction. Preliminary phase I/II results in ITP showed rilzabrutinib was efficacious and safe at all dose levels, including the optimal 400 mg BID dose (NCT03395210). Aims: Assess efficacy/safety of rilzabrutinib with longer follow‐up at 400 mg BID and in long‐term extension (LTE). Methods: Eligible patients had 2 baseline platelet counts <30×109/L. Concomitant ITP therapy was permitted at stable doses. Primary endpoints: safety and ≥2 consecutive platelet counts ≥50×109/L and increased ≥20×109/L from baseline without requiring rescue medication. All patients provided informed consent. Results: As of 09Nov2020 in 59 patients, 44 initiated rilzabrutinib 400 mg BID and to date, 14 patients with durable, stable response proceeded to LTE at 400 mg BID. For patients initiating rilzabrutinib 400 mg BID, baseline median age was 49 y, median prior therapies: 5.5 (range, 1‐53; 25% prior splenectomy), and median platelet count: 16×109/L. 39% of patients initiating rilzabrutinib 400 mg BID achieved the primary endpoint at a median of 20.6 weeks (range, 1.4‐24.6) on treatment (Table 1); 50% had platelet counts ≥30×109/L by day 8. Platelet responses to rilzabrutinib were observed irrespective of prior treatment or responses. LTE patients received rilzabrutinib for a median of 55.9 weeks (range, 13.9‐84.3). All LTE patients achieved the primary endpoint response in the main treatment period and maintained platelet counts ≥50×109/L for 96% of the LTE (Figure 1). Treatment‐related emergent adverse events were all grade 1/2, most commonly diarrhea and nausea, with no related bleeding/thrombotic events. Conclusions: Rilzabrutinib 400 mg BID showed rapid and durable responses and was well‐tolerated with longer follow‐up and in LTE. This ongoing study continues to assess the magnitude and durability of clinical benefit of rilzabrutinib in ITP