Background: A critical-sized bone defect (CsBD) is considered one that will not heal spontaneously and requires reconstruction. This study aims to compare the results of using different bone reconstructive techniques and to study the potential of platelet-rich fibrin (PRF) to enhance the healing properties of a bone substitute (BS). Methods: In this experimental study on rats, the treatment of critical-sized bone defects was carried out by analysing four groups: a control group in which the bone defect was left empty; a group treated with Bio-Gen^®; another group in which the defect was treated with PRF in combination with Bio-Gen^®; and the last that was treated with autologous bone graft (ABG). The defects were evaluated by microcomputed tomography (µCT) and then histomorphometrically. Results: From both the histological and imagistic point of view, the best results were registered in the ABG group, followed by the group treated with Bio-Gen^® with PRF, Bio-Gen^® group, and control group, with statistically significant differences. Conclusions: A 5 mm defect in the rat radius can be considered critical. ABG showed the best results in treating the bone defect. PRF significantly enhanced the efficacy of Bio-Gen^®.

Background: Hepatocellular carcinoma (HCC) is a prevalent malignancy with high mortality, often arising in the context of chronic liver diseases. Heme oxygenase-1 (HO-1), an inducible enzyme involved in heme degradation, has been implicated in both hepatoprotection and tumor progression. This study evaluates the expression of HO-1 in HCC and its association with clinicopathological features and patient survival. Materials and Methods: We retrospectively analyzed 58 HCC cases diagnosed between 2018 and 2023 at “Sf. Spiridon” Emergency County Hospital, Iasi. HO-1 expression was assessed immunohistochemically and quantified using a semi-quantitative immunoreactivity score (IRS). Statistical correlations between HO-1 expression and clinical, pathological, and survival parameters were evaluated using univariate analysis, ROC curves, and Kaplan–Meier survival models. Results: High HO-1 expression (IRS > 1) was significantly associated with hepatitis C virus etiology (p = 0.004, V = 0.381), vascular invasion (p = 0.019, V = 0.309) and perioperative anticoagulant therapy (p = 0.007, V = 0.352). However, HO-1 expression did not correlate with overall survival (OS). In contrast, solid growth pattern (p = 0.030) and serum α-fetoprotein levels of 10–99 ng/mL (p = 0.022) were negatively associated with OS. Conclusions: HO-1 expression in HCC was found to be associated with vascular invasion, but not with overall survival. While this may indicate a potential link to certain aggressive tumor features, the overall role of HO-1 in HCC biology remains unclear. These findings suggest that HO-1 should be considered an exploratory rather than definitive prognostic marker, and further research is warranted to clarify its function and potential utility, including investigation of its detectability in biological fluids for non-invasive monitoring.

Digestive malignancies remain a major cause of cancer-related mortality, with tumor progression (TP) being strongly influenced by the complex interactions between tumor cells (TCs) and their microenvironment. This review summarizes recently described mechanisms of interactions between tumor cells, macrophages and CD8+ T lymphocytes in colorectal and gastric cancer. PubMed and Web of Science were searched for studies published between 2020 and 2026, with the final search being conducted on 8 July 2026. Experimental and clinical studies, together with relevant reviews, were considered to examine these interactions and their therapeutic implications. The evidence shows a bilateral crosstalk in which tumor cells influence immune cell phenotype and function, while immune cells can further support or restrict tumor progression. These interactions involve receptor-ligand systems and paracrine signaling, followed by changes in intracellular pathways regulating proliferation, invasion, macrophage polarization and CD8+ T-cell exhaustion. Considerable methodological heterogeneity among studies limits a direct comparison of the reported mechanisms. Several therapeutic approaches targeting these interactions are currently being investigated in early-phase clinical trials. However, many components of tumor–immune crosstalk and their connections remain incompletely understood. A further characterization of these mechanisms may help identify therapeutic strategies able to interfere with the immunosuppressive microenvironment of colorectal and gastric cancers.