RPGRIP1L as a new biomarker for prognosis and tumor immune of breast cancer.

The Retinitis pigmentosa GTPase regulator interacting protein 1-like (RPGRIP1L) gene encodes an important protein that performs various physiological functions. Variants of RPGRIP1L are related to a number of diseases. However, it is currently unknown whether RPGRIP1L is correlated with breast invasive carcinoma (BRCA). In BRCA tissue specimens, the expression of RPGRIP1L was found to be elevated in comparison to its levels in normal breast tissue. A notable decline in survival rates was associated with patients exhibiting heightened RPGRIP1L gene expression. Consistent with these findings, our data also show the above results. Furthermore, elevated expression of RPGRIP1L corresponded with a spectrum of unfavorable clinicopathological features, including the presence of human epidermal growth factor receptor 2 (HER2) positive, estrogen receptor (ER) positive, over 60 years old, T2, N0, and N3. At the same time, our research indicated that 50 genes and 15 proteins were positively related to RPGRIP1L, and that these proteins and genes were mostly involved in T cell proliferation, immune response, cytokine activity, and metabolic regulation. In addition, in the present study, there was a significant correlation between RPGRIP1L expression and immune cell infiltration. Finally, we found that four Chemicals could downregulate the expression of RPGRIP1L. Altogether, our results strongly indicated that RPGRIP1L might serve as a new prognostic biomarker for BRCA.

Biomimetic Liposome with Surface-Bound Elastase for Enhanced Tumor Penetration and Chemo-Immumotherapy.

Dense extracellular matrix (ECM) in the tumor stroma has been a challenge for drug penetration and cytotoxic T lymphocyte (CTL) infiltration. Neutrophil elastase (NE), in surface-bound form, can destruct ECM rapidly, may be used for remodeling tumor ECM, and overcoming tumor stromal barrier. Focusing on elastosis in triple-negative breast tumor, biomimetic liposomes with chimeric cell membrane proteins (LMP) are developed and for the first time, it is demonstrated that LMP with surface-bound elastase (NE-LMP) can target and degrade ECM effectively in tumor stroma, with minimal toxicity to normal tissues. The pretreatment of NE-LMP increases the accumulation of chemotherapeutics at the tumor site and enhances antitumor effects. Also, NE-LMP facilitates CTL infiltration in tumors and exhibits enhanced chemo-immunotherapy in combination of PD-1 immune checkpoint blockade treatment in orthotopic 4T1 tumor-bearing mice, with significantly prolonged survival. Moreover, the remodeling of the tumor ECM by NE-LMP shows inhibiting effects on metastasis in the lung. Findings from this study suggest that NE-LMP holds promise for enhancing deep penetration of drug and infiltration of CTL in desmoplastic tumor by effective degrading ECM in the tumor stroma.