Association of the combined parameters including the frequency of primary cilia, PD-L1, Smoothened protein, membranous β-catenin and cytoplasmic β-catenin expression with the outcome of patients with clear cell renal cell carcinoma

AIMS

The objective of this study was to investigate the association and combined prognostic significance of the PD-L1, Smoothened protein and β-catenin expressions in patients with clear cell renal cell carcinoma (ccRCC).

METHODS

The PD-L1, Smoothened protein and β-catenin expression were evaluated in 104 ccRCC patients. All studied tumor samples were acquired from nephrectomy specimens of primary tumors and not from biopsies or metastases. An indirect immunohistochemistry using polyclonal rabbit anti-Smoothened antibody, monoclonal mouse anti-human β-catenin-1 antibody, immunohistochemical assay PD-L1 28-8 pharmDx using monoclonal rabbit anti-PD-L1 antibody and anti-VHL (C- terminal) rabbit antibody was used. Immunohistochemistry was scored semiquantitavely.

RESULTS

Median overall survival (OS) was significantly better in patients with lower PD-L1 expression (≤5%), Smoothened protein (SMO) expression (<5%) or cytoplasmic β-catenin expression (≤75%) than in patients with higher expressions of these biomarkers (P<0.001, P=0.047, and P<0.001, respectively). Membranous β-catenin showed an opposite effect with its lower expression (≤75%) being associated with longer OS (P=0.020). There was significant association between PD-1 and PD-L1 expression (P=0.007) and significant association of tumor grade (WHO 2016) with membranous β-catenin (P<0.001), cytoplasmic β-catenin (P=0.005), pVHL (P=0.042), PD-L1 (P=0.049) and PD-1 (P=0.028) expression.

CONCLUSION

The present study provides the first data on the potential association and combined prognostic significance of frequency of primary cilia, PD-L1, Smoothened protein and β-catenin expression with the outcome in clear cell renal cell carcinoma.

Treatment of patients with cancer using PD‑1/PD‑L1 antibodies: Adverse effects and management strategies (Review)

In 2020, there were an estimated 19.3 million new cancer cases and close to 10 million cancer deaths worldwide. Cancer remains one of the leading causes of death. In recent years, with the continuous improvement of our understanding of tumor immunotherapy, immunotherapeutics, such as immune checkpoint inhibitors, have gradually become a hot spot for tumor treatment. Amongst these, programmed cell death protein 1/programmed cell death protein ligand 1 (PD-1/PD-L1) related inhibitors, such as nivolumab and pembrolizumab, atezolizumab, avelumab and durvalumab have been shown to exhibit a high level of efficacy in several types of tumors. It has been confirmed that these inhibitors play an important role in the anti-tumor process, significantly improving the survival rate of patients and delaying the progress of the underlying cancer. However, its method of therapeutic interference and potential for damaging the immune system has caused concern regarding its suitability. As these adverse effects are caused by an immune response to endogenous tissues, they are designated as immune-related adverse events (irAEs). In this review, the typical irAEs reported in recent years and the management strategies adopted are highlighted, to serve as a reference in assessing the clinical response to these adverse reactions.

Human Umbilical Cord Mesenchymal Stem Cells Promote Macrophage PD-L1 Expression and Attenuate Acute Lung Injury in Mice

BACKGROUND

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) remains a serious clinical problem but has no approved pharmacotherapy. Mesenchymal stem cells (MSCs) represent an attractive therapeutic tool for tissue damage and inflammation owing to their unique immunomodulatory properties. The present study aims to explore the therapeutic effect and underlying mechanisms of human umbilical cord MSCs (UC-MSCs) in ALI mice.

OBJECTIVE

In this study, we identify a novel mechanism for human umbilical cord-derived MSCs (UC-MSCs)-mediated immunomodulation through PGE2-dependent reprogramming of host macrophages to promote their PD-L1 expression. Our study suggests that UC-MSCs or primed-UC-MSCs offer new therapeutic approaches for lung inflammatory diseases.

METHODS

Lipopolysaccharide (LPS)-induced ALI mice were injected with 5×105 UC-MSCs via the tail vein after 4 hours of LPS exposure. After 24 hours of UC-MSC administration, the total protein concentration and cell number in the bronchoalveolar lavage fluid (BALF), and cytokine levels in the lung tissue were measured. Lung pathological changes and macrophage infiltration after UC-MSC treatment were analyzed. Moreover, in vitro co-culture experiments were performed to analyze cytokine levels of RAW264.7 cells and Jurkat T cells.

RESULTS

UC-MSC treatment significantly improved LPS-induced ALI, as indicated by decreased total protein exudation concentration and cell number in BALF, and reduced pathological damage in ALI mice. UC-MSCs could inhibit pro-inflammatory cytokine levels (IL-1β, TNF-α, MCP-1, IL-2, and IFN-γ), whereas enhancing anti-inflammatory cytokine IL-10 expression, as well as reduced macrophage infiltration into the injured lung tissue. Importantly, UC-MSC administration increased programmed cell death protein ligand 1 (PD-L1) expression in the lung macrophages. Mechanistically, UC-MSCs upregulated cyclooxygenase-2 (COX2) expression and prostaglandin E2 (PGE2) secretion in response to LPS stimulation. UC-MSCs reduced the inflammatory cytokine levels in murine macrophage Raw264.7 through the COX2/PGE2 axis. Furthermore, UC-MSC-derived PGE2 enhanced PD-L1 expression in RAW264.7 cells, which in turn promoted programmed cell death protein 1 (PD-1) expression and reduced IL-2 and IFN-γ production in Jurkat T cells.

CONCLUSION

Our results suggest that UC-MSCs attenuate ALI via PGE2-dependent reprogramming of macrophages to promote their PD-L1 expression.

Distinct PD-L1/PD1 Profiles and Clinical Implications in Intrahepatic Cholangiocarcinoma Patients with Different Risk Factors

Rationale: PD1/PD-L1 immune checkpoint inhibitors have shown promising results for several malignancies. However, PD1/PD-L1 signaling and its therapeutic significance remains largely unknown in intrahepatic cholangiocarcinoma (ICC) cases with complex etiology. Methods: We investigated the expression and clinical significance of CD3 and PD1/PD-L1 in 320 ICC patients with different risk factors. In addition, we retrospectively analyzed 7 advanced ICC patients who were treated with PD1 inhibitor. Results: The cohort comprised 233 patients with HBV infection, 18 patients with hepatolithiasis, and 76 patients with undetermined risk factors. PD-L1 was mainly expressed in tumor cells, while CD3 and PD1 were expressed in infiltrating lymphocytes of tumor tissues. PD1/PD-L1 signals were activated in tumor tissues, and expression was positively correlated with HBV infection and lymph node invasion. More PD1⁺ T cells and higher PD-L1 expression were observed in tumor tissues of ICC patients with HBV infection compared to patients with hepatolithiasis or undetermined risk factors. More PD1⁺ T cells and/or high PD-L1 expression negatively impacted the prognosis of patients with HBV infection but not those with hepatolithiasis. Multivariate analysis showed PD1/PD-L1 expression was an independent indicator of ICC patient prognosis. Advanced ICC patients with HBV infection and less PD1⁺ T cells tended to have good response to anti-PD1 therapy. Conclusion: Hyperactivated PD1/PD-L1 signals in tumor tissues are a negative prognostic marker for ICCs after resection. HBV infection- and hepatolithiasis-related ICCs have distinct PD1/PD-L1 profiles. Further, PD1⁺ T cells could be used as a biomarker to predict prognosis and assay the efficiency of anti-PD1 immunotherapy in ICC patients with HBV infection.

Immune-related adverse events during anticancer immunotherapy: Pathogenesis and management

Immunotherapy is one of the most recent systemic treatments to emerge for use in oncology, and is based on the blocking of inhibitory immune checkpoints to potentiate the immune response to cancer. The anti-cytotoxic T lymphocyte-associated antigen-4 antibody ipilimumab and anti-programmed cell death protein 1 antibodies, including nivolumab and pembrolizumab, are currently available and widely used, and other immune-inhibiting antibodies are now under intensive investigation. These antibodies have shown efficacy in a growing number of tumor types, following initial observations of their notable effects in melanoma treatment. Despite the efficacy of these antibodies, their novel mechanisms of action are also associated with a new class of side effects called immune-related adverse events (IRAEs). These side effects do not share a common pathophysiology with other anticancer treatments and, therefore, they often require specific therapies. When detected early and correctly treated, IRAEs are reversible; however, they can become severe and life-threatening if underestimated or inappropriately treated. This review aims to revisit the pathogenesis of IRAEs, with attention to gastrointestinal manifestations, since these are common and potentially dangerous complications of immunotherapy and represent a major cause of treatment discontinuation. Recommendations and guidelines for the management of IRAEs are also presented, in order to provide a clear and applicable algorithm for use by clinicians.