Tumor-Infiltrating CD45RO+ Memory Cells Are Associated with Favorable Prognosis in Oral Squamous Cell Carcinoma Patients

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) have been used to predict the prognosis of solid tumors. In this study, we investigated which molecules in TILs play a role in the prognosis of patients with oral squamous cell carcinoma (OSCC).

METHODS

In a retrospective case-control study, we immunohistochemically evaluated the expression of CD3, CD8, CD45RO, Granzyme B, and the major histocompatibility complex class I chain-related molecule A (MICA) of the histocompatibility complex as predictors of prognosis in 33 patients with OSCC. The patients were classified as TILs^High or TILs^Low according to the number of TILs for each molecule in the central tumor (CT) and invasive margin (IM). Furthermore, MICA expression scores were determined based on the intensity of the staining.

RESULTS

CD45RO⁺/TIL in the nonrecurrent group were significantly higher than those in the recurrent group in the CT and IM areas (p < 0.05). The disease-free survival/overall survival rate of the CD45RO⁺/TILs^Low group in the CT and IM areas and the Granzyme B⁺/TILs^Low group in the IM area was significantly lower than that of the CD45RO⁺/TILs^High group and the Granzyme B⁺/TILs^High group, respectively (p < 0.05). Furthermore, the MICA expression score of tumors around the CD45RO⁺/TILs^High group was significantly higher than that of the CD45RO⁺/TILs^Low group (p < 0.05).

CONCLUSIONS

A high ratio of CD45RO-expressing TILs was associated with a disease-free/overall survival improvement in OSCC patients. Furthermore, the number of TILs that express CD45RO was associated with the expression of MICA in tumors. These results suggest that CD45RO-expressing TILs are useful biomarkers for OSCC.

Restoration of natural killer activity in hepatocellular carcinoma by treatment with antibody against granulin-epithelin precursor

Impairment of natural killer (NK) cell activity is an important mechanism of tumor immunoevasion. We have previously shown that expression of granulin-epithelin precursor (GEP) in hepatocellular carcinoma (HCC) cells rendered the cells resistant to NK cell immunosurveillance. Here, we examined whether targeting GEP could rescue NK activity in HCC patients. The current study demonstrated that quantities and activities of NK cells were significantly lower in HCC patients compared with healthy individuals, and were negatively correlated with GEP levels in HCC cells. NK cells demonstrated enhanced expression of the stimulatory receptors natural-killer group 2, member D (NKG2D) and CD69, increased secretion of IFN-γ and perforin, and cytotoxicity against HCC cells upon GEP suppression. Opposite phenotypes of NK cells were observed when GEP was overexpressed in HCC cells. Importantly, GEP blockage by monoclonal antibody A23 restored NK activity in HCC patients and sensitized HCC cells to NK cytotoxicity. Furthermore, A23 induced NK-mediated antibody-dependent cell-mediated cytotoxicity against HCC. In summary, the activity of NK cells in HCC was impaired by GEP expression, which could be rescued by GEP antibody. This study provides new insight for treatments targeting GEP to boost NK activity in HCC patients.

Soluble MICA-NKG2D interaction upregulates IFN-γ production by activated CD3-CD56+ NK cells: potential impact on chronic graft versus host disease

A soluble isoform of MHC class I chain-related molecule A (soluble MICA), generated by proteolytic shedding from the membrane-bound MICA of various tumor cells, has been shown to downregulate both the expression of natural killer group 2-member D receptor and the cytotoxic function of effectors cells and was postulated as a mechanism for tumor immune evasion. Its effect on the expression of cytokines by the effector cells remained unexplored. Here we demonstrate that the sMICA molecules upregulate interferon gamma expression by interleukin-12/interleukin-18-activated CD3(-)CD56(+) natural killer cells, witnessing the pro-inflammatory effect of soluble MICA. Overall, these data are in line with our previous observations that the raised serum levels of soluble MICA, following allogeneic hematopoietic stem cell transplantation, confer susceptibility to and the presence of pre-transplantation anti-MICA antibodies in the patient's serum confer protection against chronic graft versus host disease.