Noncoding RNA 886 alleviates tumor cellular immunological rejection in host C57BL/C mice

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Non-coding RNA 886 (nc886/VTRNA2-1) is a Pol III transcript involved in innate immunity.
• nc886 silencing correlates with prostate cancer progression.
• Previous studies established nc886 overexpression models in prostate cancer cells, showing reduced invasiveness.

Purpose of the Study:

• To investigate the immune mechanisms of tumor-host interactions using nc886-overexpressing prostate cancer cells in an immunocompetent mouse model.
• To elucidate the role of nc886 in regulating tumor cell antigens and immune responses.

Main Methods:

• Direct injection of nc886-overexpressing (mimic) or control (scramble) prostate cancer cells into the left ventricle of C57BL/C mice.
• Monitoring of organ inflammation, tissue repair, and immune cell responses (macrophages, T cells) over 28 days.
• Analysis of human leukocyte antigen (HLA) molecule and antigen transporter expression in tumor cells.

Main Results:

• Tumor cells induced xenogeneic antigen rejection and organ inflammation, followed by tissue fibrosis, except in the spleen.
• nc886 mimic cells were recognized by immune cells in circulation, with fewer cells reaching the spleen compared to scramble cells.
• Scramble cells induced splenic macrophage polarization to M2, contributing to chronic splenic inflammation.
• nc886 was found to decrease the expression of HLA molecules and antigen transporters on tumor cells.

Conclusions:

• nc886 plays a role in modulating tumor cell antigenicity and immune recognition.
• The spleen's immune response differs due to varying tumor cell distribution and macrophage polarization.
• nc886 influences tumor-host interactions by affecting immune cell infiltration and antigen presentation, potentially impacting prostate cancer progression.