Effects of reprogrammed splenic CD8+ T-cells in vitro and in mice with spontaneous metastatic Lewis lung carcinoma

BACKGROUND

Metastatic disease is a major and difficult-to-treat complication of lung cancer. Considering insufficient effectiveness of existing therapies and taking into account the current problem of lung cancer chemoresistance, it is necessary to continue the development of new treatments.

METHODS

Previously, we have demonstrated the antitumor effects of reprogrammed CD8+ T-cells (rCD8+ T-cells) from the spleen in mice with orthotopic lung carcinoma. Reprogramming was conducted by inhibiting the MAPK/ERK signalling pathway through MEKi and the immune checkpoint PD-1/PD-L1. Concurrently, CD8+ T-cells were trained in Lewis lung carcinoma (LLC) cells. We suggested that rCD8+ T-cells isolated from the spleen might impede the development of metastatic disease.

RESULTS

The present study has indicated that the reprogramming procedure enhances the survival and cytotoxicity of splenic CD8+ T-cells in LLC culture. In an LLC model of spontaneous metastasis, splenic rCD8 + T-cell therapy augmented the numbers of CD8+ T-cells and CD4+ T-cells in the lungs of mice. These changes can account for the partial reduction of tumors in the lungs and the mitigation of metastatic activity.

CONCLUSIONS

Our proposed reprogramming method enhances the antitumor activity of CD8+ T-cells isolated from the spleen and could be valuable in formulating an approach to treating metastatic disease in patients with lung cancer.

Analysis of Circulating Tumor and Cancer Stem Cells Provides New Opportunities in Diagnosis and Treatment of Small Cell Lung Cancer

Current methods for diagnosis and treatment of small cell lung cancer (SCLC) have only a modest efficacy. In this pilot study, we analyzed circulating tumor cells (CTCs) and cancer stem cells (CSCs) in patients with SCLC to search for new diagnostic and prognostic markers and novel approaches to improve the treatment of the disease. In other forms of lung cancer, we showed a heterogeneity of blood CTCs and CSCs populations, as well as changes in other cell populations (ALDH⁺, CD87⁺CD276⁺, and EGF⁺Axl⁺) in smokers. A number of CTCs and CSCs in patients with SCLC have been shown to be resistant to chemotherapy (CT). High cytotoxic activity and resistance to apoptosis of reprogrammed CD3⁺CD8⁺ T-lymphocytes (rTcells) in relation to naive CD3⁺CD8⁺ T-lymphocytes was demonstrated in a smoking patient with SCLC (Patient G) in vitro. The target for rTcells was patient G’s blood CSCs. Reprogramming of CD3⁺CD8⁺ T-lymphocytes was carried out with the MEK1/2 inhibitor and PD-1/PD-L1 pathway blocker nivolumab. The training procedure was performed with a suspension of dead CTCs and CSCs obtained from patient’s G blood. The presented data show a new avenue for personalized SCLC diagnosis and targeted improvement of chemotherapy based on the use of both CTCs and CSCs.

Reprogrammed CD8+ T-Lymphocytes Isolated from Bone Marrow Have Anticancer Potential in Lung Cancer

CD8⁺ T-lymphocytes play a key role in antitumor immune response. Patients with lung cancer often suffer from T-lymphocyte dysfunction and low T-cell counts. The exhaustion of effector T-lymphocytes largely limits the effectiveness of therapy. In this study, reprogrammed T-lymphocytes used MEK inhibitors and PD-1 blockers to increase their antitumor activity. Antitumor effects of reprogrammed T-lymphocytes were shown in vitro and in vivo in the Lewis lung carcinoma model. The population of T- lymphocytes with persistent expression of CCR7 was formed as a result of reprogramming. Reprogrammed T-lymphocytes were resistant to apoptosis and characterized by high cytotoxicity against Lewis lung carcinoma (LLC) cells in vitro. Administration of reprogrammed T-lymphocytes to C57BL/6 mice with LLC reduced the number of lung metastases. The antitumor effect resulted from the elimination of tumor cells and cancer stem cells, and the effect of therapy on cytotoxic T-lymphocyte counts. Thus, reprogramming of T-lymphocytes using MEK inhibitors is a promising approach for targeted therapy of lung cancer.

Endogenous plasma sex hormones in pre- and postmenopausal women with breast cancer: results from a case-control study in Moscow

Plasma sex hormone-binding globulin (SHBG), testosterone, total oestradiol (E2) and proportion of E2 not bound to blood proteins (percentage free E2) have been measured in a case-control study to test whether any of these factors are related to the risk of breast cancer. The cases studied were 27 premenopausal and 34 postmenopausal women with newly diagnosed localized breast cancer who were admitted to the All-Union Cancer Research Centre, Moscow. The controls were an equivalent number of women from the same neighbourhood. These were matched for age (within 2 years) and menopausal status. The average levels of E2 in cases were significantly higher than controls (p = 0.004 and p < 0.001 for pre- and postmenopausal groups, respectively). Percentage free E2 was significantly raised only in premenopausal cases (p = 0.019). The plasma concentrations of testosterone and SHBG were similar for both pre- and postmenopausal groups. Raised E2 or percentage free E2 was associated with an increased relative risk of breast cancer. However, only E2 levels (crude or adjusted for body build) were significantly related to risk in the two menopausal sets (p = 0.022 and p = 0.002, respectively). High percentage free E2 was associated with almost a threefold increase in the risk of breast cancer in premenopausal women; however, this increase was not statistically significant (p = 0.083). The levels of SHBG or testosterone, crude or adjusted for body build and E2 concentration, were not related to risk of breast cancer.