Chemotherapy of colorectal liver metastases induces a rapid rise in intermediate blood monocytes which predicts treatment response

Monocyte subsets in breast cancer patients under treatment with aromatase inhibitor and mucin-1 cancer vaccine

BACKGROUND

Monocytes comprise subsets of classical, intermediate and non-classical monocytes with distinct anti- or pro-tumor effects in breast cancer (BC). They are modulated by estrogen, and can contribute to BC control by endocrine therapy in preclinical models.

METHODS

To elucidate whether changes in monocyte subsets are associated with treatment and response, we investigated peripheral blood samples of 73 postmenopausal women with estrogen receptor (ER) positive BC, who received aromatase inhibitor therapy with or without the mucin-1 vaccine tecemotide in the ABCSG34 trial. Blood was retrieved at baseline, midterm and end of therapy, and was analyzed for the distribution and ER expression of monocyte subsets by flow cytometry.

RESULTS

When 40 healthy, age-matched women were compared with BC patients before treatment start, ER levels of monocytes did not differ, yet patients presented with a higher frequency of classical and fewer non-classical monocytes. Endocrine therapy triggered a significant increase in ER levels in all monocyte subsets, without affecting subset distribution. Vaccination had no overall impact on subset frequency and ER expression. Yet, a shift from intermediate to classical monocytes during therapy correlated with changes in plasma cytokines and chemokines and was significantly associated with low residual cancer burden in vaccinated patients. Without tecemotide, baseline ER levels in classical monocytes were significantly higher in women with good response to endocrine therapy.

CONCLUSIONS

This study identified classical monocytes to be associated with ER positive BC and with patient response to neoadjuvant endocrine treatment and cancer vaccination.

EphA4 signaling is involved in the phenotype of well-differentiated oral squamous cell arcinoma with decreased tumor immunity

Metronomic chemotherapy is defined as a high-frequency low-dose schedule of chemotherapy drug administration. Although metronomic chemotherapy is widely used, the mechanisms underlying resistance to metronomic chemotherapy remain unclear. Therefore, we herein conducted a single institutional phase I/II trial to assess the efficacy and safety of metronomic chemotherapy with bleomycin plus S-1, an oral 5-FU prodrug, in the neoadjuvant setting for patients with oral squamous cell carcinoma (OSCC). The response rate of well-differentiated OSCC to metronomic chemotherapy was significantly lower. We investigated differences in molecular profiles between poorly or moderately differentiated head and neck squamous cell carcinoma (HNSCC) and well-differentiated HNSCC from patients with HNSCC TCGA data. EphA4 expression positively correlated with histological differentiation. An upstream regulator analysis correlated with EphA4 expression identified pathways associated with decreased mTORC1 signaling and T cell activation, including TCR, CD3, CD28, and CD40LG. An EphA4 blocking peptide (KYL) induced mTOR activation in well-differentiated OSCC cell lines. Plasmacytoid dendritic cell and CD8⁺ T cell numbers were higher in the microenvironment of poorly or moderately differentiated HNSCC than in that of well-differentiated HNSCC. Well-differentiated HNSCC had the characteristics of "cold tumors" (immune-excluded tumors). Moreover, KYL used with chemotherapeutic drugs synergistically increased cancer cell death. Well-differentiated OSCC is depleted of immune cells, which may be partly explained by the receptor tyrosine kinase EphA4.

Monocyte programming by cancer therapy

Monocytes in peripheral blood circulation are the precursor of essential cells that control tumor progression, that include tumor-associated macrophages (TAMs), dendritic cells (DCs) and myeloid-derive suppressor cells (MDSC). Monocytes-derived cells orchestrate immune reactions in tumor microenvironment that control disease outcome and efficiency of cancer therapy. Four major types of anti-cancer therapy, surgery, radiotherapy, chemotherapy, and most recent immunotherapy, affect tumor-associated macrophage (TAM) polarization and functions. TAMs can also decrease the efficiency of therapy in a tumor-specific way. Monocytes is a major source of TAMs, and are recruited to tumor mass from the blood circulation. However, the mechanisms of monocyte programming in circulation by different therapeutic onsets are only emerging. In our review, we present the state-of-the art about the effects of anti-cancer therapy on monocyte progenitors and their dedifferentiation, on the content of monocyte subpopulations and their transcriptional programs in the circulation, on their recruitment into tumor mass and their potential to give origin for TAMs in tumor-specific microenvironment. We have also summarized very limited available knowledge about genetics that can affect monocyte interaction with cancer therapy, and highlighted the perspectives for the therapeutic targeting of circulating monocytes in cancer patients. We summarized the knowledge about the mediators that affect monocytes fate in all four types of therapies, and we highlighted the perspectives for targeting monocytes to develop combined and minimally invasive anti-cancer therapeutic approaches.

Peripheral Blood Monocyte Abundance Predicts Outcomes in Patients with Breast Cancer

Biomarkers of response are needed in breast cancer to stratify patients to appropriate therapies and avoid unnecessary toxicity. We used peripheral blood gene expression and cell type abundance to identify biomarkers of response and recurrence in neoadjuvant chemotherapy treated breast cancer patients. We identified a signature of interferon and complement response that was higher in the blood of patients with pathologic complete response. This signature was preferentially expressed by monocytes in single cell RNA sequencing. Monocytes are routinely measured clinically, enabling examination of clinically measured monocytes in multiple independent cohorts. We found that peripheral monocytes were higher in patients with good outcomes in four cohorts of breast cancer patients. Blood gene expression and cell type abundance biomarkers may be useful for prognostication in breast cancer.

Significance

Biomarkers are needed in breast cancer to identify patients at risk for recurrence. Blood is an attractive site for biomarker identification due to the relative ease of longitudinal sampling. Our study suggests that blood-based gene expression and cell type abundance biomarkers may have clinical utility in breast cancer.

Kefir Is a Viable Exercise Recovery Beverage for Cancer Survivors Enrolled in a Structured Exercise Program

PURPOSE

This study investigated the effects of 12 wk of postexercise kefir consumption in cancer survivors who have undergone chemotherapy and/or radiation therapy.

METHODS

All participants were enrolled in a structured exercise training program and separated into kefir (KEF) or control (CON) treatment groups. KEF consumed 8 oz. of kefir after exercise sessions (3 d·wk-1) for 12 wk. Outcome measures included assessments for body size and composition, aerobic fitness and muscular strength, medical history, and psychological state at pre- and postintervention time points. Blood was collected and analyzed for C-reactive protein (CRP), interleukin 6 (IL-6), and lipopolysaccharide (LPS) concentrations, and LPS-stimulated whole blood IL-6 and tumor necrosis factor α production were obtained using enzyme-linked immunosorbent assays at both time points. Monocyte numbers and phenotype were obtained using flow cytometry.

RESULTS

Participants (N = 24; 9 males and 15 females) were an average of 61 ± 9.9 yr old. Kefir consumption was associated with 6.3% (P = 0.034) improvements in lean body mass, as well as 51.4% (P = 0.046), 39.3% (P = 0.017), and 64.7% (P = 0.021) improvements in measures of depression, fatigue, and gastric distress, respectively. KEF also experienced a significant 35.4% (P = 0.01) reduction in circulating LPS along with an 18.0% increase (P < 0.001) in classical monocytes % and a 22.3% decrease (P = 0.04) in nonclassical monocytes %. There were no significant changes in any other variables.

CONCLUSION

Twelve weeks of kefir consumption improved lean body mass, depression, fatigue, gastric distress, and a biomarker of gut dysbiosis. Kefir improved overall and classical monocyte numbers. Kefir should be considered as a component of a postexercise dietary regimen for cancer survivors.

Effects of Chemotherapy Agents on Circulating Leukocyte Populations: Potential Implications for the Success of CAR-T Cell Therapies

Simple Summary

CAR-T cell therapy is a new approach to cancer treatment that is based on manipulating a patient’s own T cells such that they become able to seek and destroy cancer cells in a highly specific manner. This approach is showing remarkable efficacy in treating some types of blood cancers but so far has been much less effective against solid cancers. Here, we review the diverse effects of chemotherapy agents on circulating leukocyte populations and find that, despite some negative effects over the short term, chemotherapy can favourably modulate the immune systems of cancer patients over the longer term. Since blood is the starting material for CAR-T cell production, we propose that these effects could significantly influence the success of manufacturing, and anti-cancer activity, of CAR-T cells. Thus, if timed correctly, chemotherapy-induced changes to circulating immune cells could allow CAR-T cells to unleash more effective anti-tumour responses.

Abstract

Adoptive T-cell therapy using autologous T cells genetically modified to express cancer-specific chimeric antigen receptors (CAR) has emerged as a novel approach for cancer treatment. CAR-T cell therapy has been approved in several major jurisdictions for treating refractory or relapsed cases of B-cell precursor acute lymphoblastic leukaemia and diffuse large B-cell lymphoma. However, in solid cancer patients, several clinical studies of CAR-T cell therapy have demonstrated minimal therapeutic effects, thus encouraging interest in better integrating CAR-T cells with other treatments such as conventional cytotoxic chemotherapy. Increasing evidence shows that not only do chemotherapy drugs have tumoricidal effects, but also significantly modulate the immune system. Here, we discuss immunomodulatory effects of chemotherapy drugs on circulating leukocyte populations, including their ability to enhance cytotoxic effects and preserve the frequency of CD8⁺ T cells and to deplete immunosuppressive populations including regulatory T cells and myeloid-derived suppressor cells. By modulating the abundance and phenotype of leukocytes in the blood (the ‘raw material’ for CAR-T cell manufacturing), we propose that prior chemotherapy could facilitate production of the most effective CAR-T cell products. Further research is required to directly test this concept and identify strategies for the optimal integration of CAR-T cell therapies with cytotoxic chemotherapy for solid cancers.

Hepatobiliary surgeons meet immunologists: the case of colorectal liver metastases patients

The burgeoning field of cancer immunology demands a change in the paradigm of cancer patient management. The understanding of the course of a given malignant disease should also include the host immune system as one of the key factors in determining the patient's prognosis. Surgical and medical oncologists need to understand the basic and advanced applications of immunotherapies, which are rapidly evolving, and are nowadays an integral part of the armamentarium for the treatment of cancer patients. In the present work, we review the current knowledge concerning the immune landscape of colorectal cancer (CRC) patients with liver metastases, as recently discovered.

Macrophages in Colorectal Cancer Liver Metastases

Tumor-associated macrophages (TAMs) provide a nurturing microenvironment for metastasis and are concomitantly key determinants of the efficacy of anticancer strategies. TAM represent an extremely heterogeneous population in terms of cell morphology, functions, and tissue localization. Colorectal liver metastases (CLM) display a high heterogeneity, responsible for a wide array of clinical presentations and responsiveness to treatments. In the era of precision medicine, there is a critical need of reliable prognostic markers to improve patient stratification, and, for their predominance in metastatic tissues, TAMs are emerging as promising candidates.

The relative change in regulatory T cells / T helper lymphocytes ratio as parameter for prediction of therapy efficacy in metastatic colorectal cancer patients

Purpose

The evaluation of regulatory T (Treg) (CD4⁺CD25^high CD127^neg) lymphocyte count with respect to the T helper (TH) (CD4) number has been shown to represent the main immune parameters capable of signifying the functional status of the anticancer immunity in cancer patients. This study is aimed to explore a correlation between therapy efficacy and changes in Treg/TH ratio and other biochemical and haematological parameters in patients with metastatic colorectal cancer (mCRC).

Experimental Design

Measurements of regulatory T cells were performed by flow cytometric analysis pre- and post-therapies in a prospective study.

Results

We investigated levels of Treg/TH ratio in the peripheral blood of 25 mCRC patients pre- and post-chemotherapy ± targeted therapy. There were significant differences in levels of Treg/TH ratio pre- and post-treatments among patients on study, patients with partial response (PR), stable disease (SD) and progressive disease (PD) (P= 0.012, P= 0.011, and P= 0.043, respectively). Moreover, the relative change in Treg/TH ratio showed statistically significant difference among patients with PD as compared to those with PR and SD. Our findings demonstrated a statistically significant strong correlation between the relative change in Treg/TH ratio and therapeutic response. (Spearman's rho= 0.788/p<0.001).

Conclusions

The monitoring of the relative change in Treg/TH ratio could constitute a promising clinical index for response prediction and a timely change in regimen. Further prospective evaluations of these parameters investigated, particularly their association with overall survival, are warranted.

TIE-2 expressing monocytes in human cancers

Tumor-associated macrophages (TAM) are well known as a key player in the tumor microenvironment, which support cancer progression. More recently, a lineage of monocytes characterized by the expression of the TIE-2/Tek angiopoietin receptor identified a subset of circulating and tumor-associated monocytes endowed with proangiogenic activity. TIE-2 expressing monocytes (TEM) were found both in humans and mice. Here, we review the phenotypes and functions of TEM reported so far in human cancer and their potential use as markers of cancer progression and metastasis. Finally, we discuss the therapeutic approaches currently used or proposed to target TEM.