Differential distribution of tumor-associated macrophages and Treg/Th17 cells in the progression of malignant and benign epithelial ovarian tumors

Fertility potential and safety assessment of residual ovarian cortex in young women diagnosed with epithelial borderline and early-stage malignant ovarian tumors

OBJECTIVE

To establish the safety and quality of ovarian cortex surrounding epithelial ovarian tumors in women eligible for fertility-sparing surgery by identifying occult malignant lesions and characterizing the ovarian follicle pool.

METHODS

Multicentric retrospective study of 48 subjects (15-45 years), diagnosed with borderline ovarian tumors (BOTs) or early-stage epithelial ovarian cancers (EOCs) and eligible for fertility-sparing surgery. Histological samples of ovarian cortex surrounding tumors were analyzed to characterize the follicle pool, find any occult malignant lesion using tumor-specific markers (cytokeratin 7 and mucin 1), and quantify tumor-infiltrating lymphocytes (TILs) by CD3 and tumor associated macrophages (TAMs) by CD68.

RESULTS

Occult ovarian lesions were observed in 6 out of 45 cases investigated (14.6%), including one mucinous stage-I BOT (1/14), one serous stage-I BOT (1/13), 3 advanced-stage serous BOTs (3/11) and one early-stage serous EOC (1/7). Notably, follicle density was significantly lower in subjects diagnosed with ovarian tumors compared to controls (p < 0.001) and at a younger age. Significantly higher follicle atresia was encountered in the ovarian tumor group then in controls (20.1 ± 8.8% vs 9.2 ± 9.4%, p < 0.001) at all ages. Both TILs and TAMs were found in ovarian tumors irrespective of histotype, but no link was established with the status of the ovarian reserve.

CONCLUSIONS

Personalized counseling for fertility preservation is required in the event of BOTs and early-stage EOCs. Fertility-sparing surgery and adjuvant gamete preservation should be considered, balancing the oncological risks according to tumor stage and histotype and fertility potential, especially at a younger age.

Reciprocal crosstalk between Th17 and mesothelial cells promotes metastasis-associated adhesion of ovarian cancer cells

BACKGROUND

IL-17A and TNF synergistically promote inflammation and tumorigenesis. Their interplay and impact on ovarian carcinoma (OC) progression are, however, poorly understood. We addressed this question focusing on mesothelial cells, whose interaction with tumor cells is known to play a pivotal role in transcoelomic metastasis formation.

METHODS

Flow-cytometry and immunohistochemistry experiments were employed to identify cellular sources of IL-17A and TNF. Changes in transcriptomes and secretomes were determined by bulk and single cell RNA sequencing as well as affinity proteomics. Functional consequences were investigated by microscopic analyses and tumor cell adhesion assays. Potential clinical implications were assessed by immunohistochemistry and survival analyses.

RESULTS

We identified Th17 cells as the main population of IL-17A- and TNF producers in ascites and detected their accumulation in early omental metastases. Both IL-17A and its receptor subunit IL-17RC were associated with short survival of OC patients, pointing to a role in clinical progression. IL-17A and TNF synergistically induced the reprogramming of mesothelial cells towards a pro-inflammatory mesenchymal phenotype, concomitantly with a loss of tight junctions and an impairment of mesothelial monolayer integrity, thereby promoting cancer cell adhesion. IL-17A and TNF synergistically induced the Th17-promoting cytokines IL-6 and IL-1β as well as the Th17-attracting chemokine CCL20 in mesothelial cells, indicating a reciprocal crosstalk that potentiates the tumor-promoting role of Th17 cells in OC.

CONCLUSIONS

Our findings reveal a novel function for Th17 cells in the OC microenvironment, which entails the IL-17A/TNF-mediated induction of mesothelial-mesenchymal transition, disruption of mesothelial layer integrity and consequently promotion of OC cell adhesion. These effects are potentiated by a positive feedback loop between mesothelial and Th17 cells. Together with the observed clinical associations and accumulation of Th17 cells in omental micrometastases, our observations point to a potential role in early metastases formation and thus to new therapeutic options.

The predictive value of NLR, PLR and MLR in the differential diagnosis of benign uterine diseases and endometrial malignant tumors

OBJECTIVE

To explore the application of neutrophils to lymphocytes ratio (NLR), platelet to lymphocyte ratio (PLR) and monocyte to lymphocyte ratio (MLR) in the differential diagnosis of benign uterine diseases and endometrial malignant tumors.

METHODS

80 patients with endometrial malignant tumor diagnosed in our hospital from January 2019 to December 2022 were selected as the study group, and 74 patients with benign uterine diseases confirmed by pathology in our hospital during the same period were randomly selected as the control group. The differences of NLR, PLR and MLR in the peripheral blood of patients in each group were compared, and the value of individual indicators in the diagnosis of endometrial malignant tumor was evaluated using the Receiver Operating Characteristic (ROC) curve.

RESULTS

In peripheral blood, the NLR, PLR and MLR value in patients with endometrial cancer (EC) were significantly higher than those in patients with benign uterine diseases (P < 0.05). The area under the curve (AUC) of NLR, PLR, MLR in peripheral blood were 0.777, 0. 675 and 0.698. The best cutoff values were 2.02, 132.06 and 0.166. The sensitivity and specificity were 62.5% and 79.7%, 62.5% and 63.5%, 81 3% and 47.3%. The combination of these three indicators can significantly improved the diagnostic efficiency in endometrial cancer (AUC = 0.780), and the sensitivity and specificity were 60% and 83.8%.

CONCLUSIONS

In peripheral blood, NLR, PLR and MLR have certain diagnostic value in the differential diagnosis of endometrial cancer. When NLR, PLR and MLR are elevated, we should be alert to the occurrence of endometrial malignant tumors, and the combined diagnostic efficiency is high.

Targeting tumor-associated macrophages for successful immunotherapy of ovarian carcinoma

Epithelial ovarian cancer (EOC) is among the top five causes of cancer-related death in women, largely reflecting early, prediagnosis dissemination of malignant cells to the peritoneum. Despite improvements in medical therapies, particularly with the implementation of novel drugs targeting homologous recombination deficiency, the survival rates of patients with EOC remain low. Unlike other neoplasms, EOC remains relatively insensitive to immune checkpoint inhibitors, which is correlated with a tumor microenvironment (TME) characterized by poor infiltration by immune cells and active immunosuppression dominated by immune components with tumor-promoting properties, especially tumor-associated macrophages (TAMs). In recent years, TAMs have attracted interest as potential therapeutic targets by seeking to reverse the immunosuppression in the TME and enhance the clinical efficacy of immunotherapy. Here, we review the key biological features of TAMs that affect tumor progression and their relevance as potential targets for treating EOC. We especially focus on the therapies that might modulate the recruitment, polarization, survival, and functional properties of TAMs in the TME of EOC that can be harnessed to develop superior combinatorial regimens with immunotherapy for the clinical care of patients with EOC.

Tumor-Infiltrating Lymphocytes (TILs) in Epithelial Ovarian Cancer: Heterogeneity, Prognostic Impact, and Relationship with Immune Checkpoints

Epithelial ovarian cancers (EOC) are often diagnosed at an advanced stage with carcinomatosis and a poor prognosis. First-line treatment is based on a chemotherapy regimen combining a platinum-based drug and a taxane-based drug along with surgery. More than half of the patients will have concern about a recurrence. To improve the outcomes, new therapeutics are needed, and diverse strategies, such as immunotherapy, are currently being tested in EOC. To better understand the global immune contexture in EOC, several studies have been performed to decipher the landscape of tumor-infiltrating lymphocytes (TILs). CD8+ TILs are usually considered effective antitumor immune effectors that immune checkpoint inhibitors can potentially activate to reject tumor cells. To synthesize the knowledge of TILs in EOC, we conducted a review of studies published in MEDLINE or EMBASE in the last 10 years according to the PRISMA guidelines. The description and role of TILs in EOC prognosis are reviewed from the published data. The links between TILs, DNA repair deficiency, and ICs have been studied. Finally, this review describes the role of TILs in future immunotherapy for EOC.

A study on the correlation between M2 macrophages and regulatory T cells in the progression of colorectal cancer

Background

M2 macrophages and regulatory T cells (Tregs) can promote tumors and development by inhibiting the anti-tumor immune response. This study investigated the effect of CD163-positive M2 macrophages and Foxp3-positive Tregs in the progression of colorectal cancer and lymph node metastasis. It also investigated the correlation between M2 macrophages and Tregs.

Methods

Postoperative tissue specimens and clinical data were collected from 197 patients with colorectal cancer who underwent initial surgical treatment in The Second Ward of Colorectal Surgery of the First Affiliated Hospital of Jinzhou Medical University from March 2020 to December 2020. Immunohistochemical methods were used to detect the expression levels of CD163 protein-labeled M2 macrophages and Foxp3 protein-labeled Tregs in colorectal cancer tissues, matched paracancer tissues, and lymph node tissues. The correlation between CD163 and Foxp3 in cancer tissues and lymph node tissues were analyzed, as well as the relationship between clinicopathological characteristics and preoperative tumor markers.

Results

M2 macrophages and Tregs were importantly positively correlated in cancer and lymph node tissues, which significantly increased in cancer and metastatic lymph node tissues. Interestingly, M2 macrophages in non-metastatic lymph nodes also increased significantly in patients with metastatic lymph nodes. In addition, both CD163 and Foxp3 were upregulated with increasing tumor node metastasis stage, depth of infiltration, and lymphatic metastasis; and both were positively correlated with carcinoembryonic antigen.

Conclusion

CD163 may be a good predictor of pre-metastatic status of colorectal cancer lymph nodes. carcinoembryonic antigen affects the distribution of M2 macrophages and Tregs in colorectal cancer. There is a certain correlation between the two types of cells. It is possible that M2 macrophages, together with suppressor Tregs cells, promote an immunosuppressive environment.

Spatiotemporal multi-scale modeling of radiopharmaceutical distributions in vascularized solid tumors

We present comprehensive mathematical modeling of radiopharmaceutical spatiotemporal distributions within vascularized solid tumors. The novelty of the presented model is at mathematical level. From the mathematical viewpoint, we provide a general modeling framework for the process of radiopharmaceutical distribution in the tumor microenvironment to enable an analysis of the effect of various tumor-related parameters on the distribution of different radiopharmaceuticals. We argue that partial differential equations (PDEs), beyond conventional methods, including ODE-based kinetic compartment modeling, can be used to evaluate radiopharmaceutical distribution in both time and space. In addition, we consider the spatially-variable dynamic structure of tumor microvascular networks to simulate blood flow distribution. To examine the robustness of the model, the effects of microvessel density (MVD) and tumor size, as two important factors in tumor prognosis, on the radiopharmaceutical distribution within the tumor are investigated over time (in the present work, we focus on the radiopharmaceutical [¹⁸F]FDG, yet the framework is broadly applicable to radiopharmaceuticals). Results demonstrate that the maximum total uptake of [¹⁸F]FDG at all time frames occurs in the tumor area due to the high capillary permeability and lack of a functional lymphatic system. As the MVD of networks increases, the mean total uptake in the tumor is also enhanced, where the rate of diffusion from vessel to tissue has the highest contribution and the rate of convection transport has the lowest contribution. The results of this study can be used to better investigate various phenomena and bridge a gap among cancer biology, mathematical oncology, medical physics, and radiology.

Preoperative LMR and Serum CA125 Level as Risk Factors for Advanced Stage of Ovarian Cancer

Objectives: This study was to analyze the relationships between lymphocyte-to-monocyte ratio (LMR) alone or combined with serum CA125 (COLC) and advanced stage of ovarian cancer (OC).

Methods: The receiver-operating characteristic (ROC) curves of LMR, CA125, and COLC staging OC were constructed by a retrospective study. Furthermore, a binary logistic regression model was used to assay the independent risk factors for OC staging.

Results: Two hundred and twenty-five patients with OC were identified in this cohort. Eighty-five OC patients were diagnosed at an early stage, and 140 OC patients were diagnosed at an advanced stage. The median of LMR in the early stage was higher than that in advanced stage (4.4 vs. 2.8), and the median of serum CA125 was lower than that in advanced stage (80 U/mL vs. 251.3 U/mL). Multivariate logistic regression LMR≤3.7 (OR=0.299, 95% CI: 0.093-0.962, P=0.043) and CA125>95.7 U/mL (OR=4.317, 95% CI: 1.436-12.977, P=0.009) were risk factors for stage of advanced OC whether presence or absence of malignant ascites. Furthermore, the area under the curve of COLC was higher than that of LMR (0.782 vs. 0.732) or serum CA125 (0.782 vs. 0.708) in staging OC. The specificity of COLC was higher than that of LMR (87.1% vs. 70.6%) or serum CA125 (87.1% vs. 61.2%) in staging OC.

Conclusion: LMR alone or in combination with serum CA125 might be associated with OC staging. Besides, as a predictive factor, COLC may have a high specificity in staging OC.

Immunotyping in tubo-ovarian high-grade serous carcinoma by PD-L1 and CD8+ T-lymphocytes predicts disease-free survival

PD-L1 immune checkpoint inhibitor expression was evaluated in high-grade serous carcinoma (HGSC) ovary in the context of the overall immune landscape to determine its prognostic value. Consecutive cases of HGSC, 50 who underwent upfront surgery followed by adjuvant chemotherapy (HGSC-U) and 50 who underwent neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (HGSC-PC) were selected. In HGSC-PC cases, the pre-NACT ascitic fluid cell blocks were included. Tumor-infiltrating lymphocytes (TILs) were scored, hotspots chosen for tissue microarray construction and immunohistochemistry performed and scored for CD4 and CD8 lymphocyte subsets, CD68+ tumor-associated macrophages (TAMs), PD-1 and PD-L1 expression. HGSC-post-chemotherapy showed increased TILs, predominantly CD8+T-lymphocytes, compared to HGSC-U. HGSC showed PD-L1 expression on tumor cells and/or TAMs in 60% cases with a linear correlation to CD4+, CD8+ TIL levels. Concordant PD-L1 expression was seen in matched pre- and post-NACT tumor cells. HGSC-PC showed higher expression of PD-L1. There was no association of PD-L1 cumulative proportion score or tumor cell score with outcome. Taking a cutoff for PD-L1 CPS at 10%, immunotype I (PD-L1+/CD-8+), corresponding to tumors with adaptive immune evasion, showed worst disease-free survival compared to all other immunotypes (p = 0.03) and was more significant (p = 0.01) when compared to immunotype III (PD-L1+/CD8-). Immunotyping based on PD-L1/CD8+ expression correlates to prognosis and outcome.

Tumor associated macrophages in the molecular pathogenesis of ovarian cancer

The tumor microenvironment is a critical factor that enhances cancer progression, drug resistance, and failure of therapeutic approaches. Several cellular and non-cellular factors are involved in cancer promotion. Among the several cell populations in the tumor microenvironment, macrophages, as one of the most abundant innate immune cells within the tumor milieu, have attracted extensive attention among several researchers because of their critical role in innate pathophysiology of multiple disorders, as well as ovarian cancer. High plasticity and consequent high ability to adapt to environmental alternations by adjusting their cellular metabolism and immunological phenotype is the notable characteristic of macrophages. Therefore, the critical function of tumor-associated macrophages in ovarian cancer is highlighted in the growing body of recent studies. In this article, we will comprehensively focus on significant impacts of the macrophages on ovarian cancer progression, by discussing the role of macrophages as one of the fundamental immune cells present in tumor milieu, in metabolic reprogramming of transformed cells, and involvement of these cells in the ovarian cancer initiation, progression, invasion, and angiogenesis. Moreover, we will summarise recent studies evaluating the effects of targeting macrophages in ovarian cancer.

The Proportion and Prognostic Significance of T-Regulatory Cells in Patients with Gynecological Cancers: A Systematic Review and Meta-Analysis

Objective: Multiple reports have described the proportion of T-regulatory cells (Tregs) in peripheral blood (PB) and tissues in patients with gynecological cancers (GCs) with controversial results. Thus, the aim of this study was to investigate the proportion of Tregs and its prognostic survival role in GCs patients.

Methods: We performed a comprehensive search from database inception for all studies presenting changes of Tregs in GCs patients versus controls to evaluate the pooled standardized mean differences (SMD) with 95% confidence intervals (95% CI). And hazard ratios (HRs) with 95% CI were recorded if available to determine the prognostic significance of Tregs.

Results: Totally, 22 studies were included. Compared with controls, GCs patients had a higher proportion of Tregs in PB (SMD = 2.32, 95% CI = 1.47 to 3.17, P = 0.000) as well as in tissues (SMD = 3.47, 95% CI = 0.77 to 6.18, P = 0.012). Furthermore, more significant elevated frequency of Tregs was observed in GCs patients with advanced stage than those in the early stage in both PB and tissues. However, no association was found between Tregs and survival of GCs patients with an HR of 1.34 (95% CI = 0.96 to 1.88, P = 0.09).

Conclusions: Compared to controls, proportion of Tregs in PB and tissues was both higher among GCs patients, and it can be considered as a clinical biomarker for screening and prediction of clinical characteristics of GCs patients. But larger researches with rigorous design should be carried to explore the deep mechanisms of Tregs in GCs.

Th17 Cells and IL-17 As Novel Immune Targets in Ovarian Cancer Therapy

Ovarian cancer (OC) is usually diagnosed at an advanced stage and is related with poor prognosis. Despite numerous studies, the pathogenesis of OC is still unknown. Recent studies indicate the role of the immune system in the development and spread of OC. The identification of factors and mechanisms involved in that process and their modulation is crucial for creating effective antitumor therapy. We investigated the potential role of Th17 cells in OC patients (n = 71) by analyzing the frequencies of Th17 cells in three different environments, i.e., peripheral blood (PB), peritoneal fluid (PF), and tissue (Th17 infiltrating cells), and the concentration of IL-17A in plasma and PF of patients in terms of their clinical and prognostic significance. Th17 cells were analyzed by flow cytometry as a percentage of CD4⁺ lymphocytes that expressed intracellular expression of IL-17A. The level of IL-17A in plasma and PF were determined by ELISA. Our results showed accumulation of Th17 cells among tumor-infiltrating CD4⁺ lymphocytes (p < 0.001 in relation to PB). Moreover, the percentage of Th17 cells in both PB and PF of OC patients was significantly lower than that in benign tumors group (n = 35). There were no significant differences in the percentage of Th17 cells in PB, PF, and tissue in relation to clinicopathological characteristics of OC patients and survival. The lower percentage of Th17 cells in the PB and PF of OC patients may promote evasion of host immune response by cancer cells. The concentration of IL-17A in plasma of OC patients was higher (p < 0.0001) than that in both benign tumors and control group (n = 10). The PF IL-17A level in OC patients was higher (p < 0.0001) than that in women with benign ovarian tumors, indicating its synthesis in OC microenvironment. Higher IL-17A level in PF is correlated with longer (median: 36.5 vs. 27 months) survival of OC patients.

Febrile Temperature Critically Controls the Differentiation and Pathogenicity of T Helper 17 Cells

Fever, an evolutionarily conserved physiological response to infection, is also commonly associated with many autoimmune diseases, but its role in T cell differentiation and autoimmunity remains largely unclear. T helper 17 (Th17) cells are critical in host defense and autoinflammatory diseases, with distinct phenotypes and pathogenicity. Here, we show that febrile temperature selectively regulated Th17 cell differentiation in vitro in enhancing interleukin-17 (IL-17), IL-17F, and IL-22 expression. Th17 cells generated under febrile temperature (38.5°C-39.5°C), compared with those under 37°C, showed enhanced pathogenic gene expression with increased pro-inflammatory activities in vivo. Mechanistically, febrile temperature promoted SUMOylation of SMAD4 transcription factor to facilitate its nuclear localization; SMAD4 deficiency selectively abrogated the effects of febrile temperature on Th17 cell differentiation both in vitro and ameliorated an autoimmune disease model. Our results thus demonstrate a critical role of fever in shaping adaptive immune responses with implications in autoimmune diseases.

Next-generation nanotheranostics targeting cancer stem cells

Cancer is depicted as the most aggressive malignancy and is one the major causes of death worldwide. It originates from immortal tumor-initiating cells called 'cancer stem cells' (CSCs). This devastating subpopulation exhibit potent self-renewal, proliferation and differentiation characteristics. Dynamic DNA repair mechanisms can sustain the immortality phenotype of cancer to evade all treatment strategies. To date, current conventional chemo- and radio-therapeutic strategies adopted against cancer fail in tackling CSCs. However, new advances in nanotechnology have paved the way for creating next-generation nanotheranostics as multifunctional smart 'all-in-one' nanoparticles. These particles integrate diagnostic, therapeutic and targeting agents into one single biocompatible and biodegradable carrier, opening up new avenues for breakthroughs in early detection, diagnosis and treatment of cancer through efficient targeting of CSCs.

Consumption of β-glucans to spice up T cell treatment of tumors: a review

INTRODUCTION

Adoptive T-cell treatments of solid cancers have evolved into a robust therapy with objective response rates surpassing those of standardized treatments. Unfortunately, only a limited fraction of patients shows durable responses, which is considered to be due to a T cell-suppressive tumor microenvironment (TME). Here we argue that naturally occurring β-glucans can enable reversion of such T cell suppression by engaging innate immune cells and enhancing numbers and function of lymphocyte effectors.

AREAS COVERED

This review summarizes timely reports with respect to absorption, trafficking and immune stimulatory effects of β-glucans, particularly in relation to innate immune cells. Furthermore, we list effects toward well-being and immune functions in healthy subjects as well as cancer patients treated with orally administered β-glucans, extended with effects of β-glucan treatments in mouse cancer models.

EXPERT OPINION

Beta-glucans, when present in food and following uptake in the proximal gut, stimulate immune cells present in gut-associated lymphoid tissue and initiate highly conserved pro-inflammatory pathways. When tested in mouse cancer models, β-glucans result in better control of tumor growth and shift the TME toward a T cell-sensitive environment. Along these lines, we advocate that intake of β-glucans provides an accessible and immune-potentiating adjuvant when combined with adoptive T-cell treatments of cancer.

M2 macrophages and regulatory T cells in lethal prostate cancer

BACKGROUND

Prostate cancer (PCa) is one of the most frequently diagnosed cancers in the world. Emerging evidence suggests that inflammatory cells such as M2 macrophages and regulatory T cells (T_regs ) can contribute to cancer progression by suppressing the anti-tumor immune response. This study investigated the number of CD163-positive M2 macrophages in PCa tissue. It also investigated the correlation and interaction of M2 macrophages and T_regs .

METHODS

This nested case-control study included subjects from a cohort of men diagnosed with PCa as an incidental finding during transurethral resection of the prostate. The cases were 225 men who died from PCa, and the controls were 367 men who survived more than 10 years after PCa diagnosis without disease progression. Infiltrating CD163-positive M2 macrophages and FOXP3/CD4-positive T_regs in PCa tissue were identified using immunohistochemistry. The correlation and interaction of M2 macrophages and T_regs were assessed using Spearman's rank-order correlation and a likelihood test, respectively. Logistic regression was used to estimate odds ratios (ORs) for lethal PCa and macrophage counts.

RESULTS

The number of M2 macrophages and T_regs showed a significant correlation (P < 0.001) but no interactions. The OR for lethal PCa was 1.93 (95%CI: 1.23-3.03) for men with high numbers of M2 macrophages. Also for cases with uncertain outcome (GS categories 3 + 4 and 4 + 3) high numbers of M2 macrophages does predict a poorer prognosis.

CONCLUSIONS

Our data showed that men with high numbers of M2 macrophages in the prostate tumor environment had increased odds of dying of PCa. It is possible that M2 macrophages, together with other suppressor cells such as T_regs , promote an immunosuppressive environment.

IL-17 and colorectal cancer: From carcinogenesis to treatment

Colorectal cancer (CRC) is one of the most common types of cancer in the world. Several factors contribute to the development of this cancer. Tumor formation in colon triggers immune responses such as immune cells proliferation, phenotype alteration, cytokine synthesis and release, which lead to IL-17 producing T cells, the differentiated CD4+ T cells i.e. T helper 17. IL-17 is a pro-inflammatory cytokine, which its level is up regulated in serum and tissues of CRC patients. Several studies have shown that IL-17 has an important role in metastasis and prognosis of CRC. The aim of this review is to summarize the role of this cytokine in tumorigenesis, angiogenesis and metastasis of CRC and discuss its value in diagnosis, prognosis and treatment of CRC.

Role of interleukin (IL)-17 and T-helper (Th)17 cells in cancer

Interleukin-17 (IL-17), a pleiotropic proinflammatory cytokine, is reported to be significantly generated by a distinct subset of CD4⁺ T-cells, upgrading cancer-elicited inflammation and preventing cancer cells from immune surveillance. T-helper (Th)17 cells produced from naive CD4⁺ T cells have recently been renowned and generally accepted, gaining eminence in cancer studies and playing the effective role in context of cancer. Th17 cells are the main source of IL-17-secreting cells, It was found that other cell types produced this cytokine as well, including Group 3 innate lymphoid cells (ILC3), δγT cells, invariant natural killer T (iNKT) cells, lymphoid-tissue inducer (LTi)-like cells and Natural killer (NK) cells. Th17-associated cytokines give impetus to tumor progression, or inducing angiogenesis and metastasis. This review demonstrates an understanding on how the pro- or antitumor function of Th17 cells and IL-17 may change cancer progression, leading to the appearance of complex and pivotal biologic activities in tumor.