Limits...
CD1d-expressing breast cancer cells modulate NKT cell-mediated antitumor immunity in a murine model of breast cancer metastasis.

Hix LM, Shi YH, Brutkiewicz RR, Stein PL, Wang CR, Zhang M - PLoS ONE (2011)

Bottom Line: Tumor tolerance and immune suppression remain formidable obstacles to the efficacy of immunotherapies that harness the immune system to eradicate breast cancer.We hypothesize that breast cancer cells, through downregulation of CD1d and subsequent evasion of NKT-mediated antitumor immunity, gain increased potential for metastatic tumor progression.The results of this study emphasize the importance of determining the CD1d expression status of the tumor when tailoring NKT-based immunotherapies for the prevention and treatment of metastatic breast cancer.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.

ABSTRACT

Background: Tumor tolerance and immune suppression remain formidable obstacles to the efficacy of immunotherapies that harness the immune system to eradicate breast cancer. A novel syngeneic mouse model of breast cancer metastasis was developed in our lab to investigate mechanisms of immune regulation of breast cancer. Comparative analysis of low-metastatic vs. highly metastatic tumor cells isolated from these mice revealed several important genetic alterations related to immune control of cancer, including a significant downregulation of cd1d1 in the highly metastatic tumor cells. The cd1d1 gene in mice encodes the MHC class I-like molecule CD1d, which presents glycolipid antigens to a specialized subset of T cells known as natural killer T (NKT) cells. We hypothesize that breast cancer cells, through downregulation of CD1d and subsequent evasion of NKT-mediated antitumor immunity, gain increased potential for metastatic tumor progression.

Methodology/principal findings: In this study, we demonstrate in a mouse model of breast cancer metastasis that tumor downregulation of CD1d inhibits iNKT-mediated antitumor immunity and promotes metastatic breast cancer progression in a CD1d-dependent manner in vitro and in vivo. Using NKT-deficient transgenic mouse models, we demonstrate important differences between type I and type II NKT cells in their ability to regulate antitumor immunity of CD1d-expressing breast tumors.

Conclusions/significance: The results of this study emphasize the importance of determining the CD1d expression status of the tumor when tailoring NKT-based immunotherapies for the prevention and treatment of metastatic breast cancer.

Show MeSH

Related in: MedlinePlus

Differences in tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice.Orthotopic injection into the bilateral mammary fat pads of CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice, with either 1×106 TM40D (CD1d-hi) or TM40D-MB (CD1d-lo) cells, 5 mice per tumor group. Mice were monitored for tumor formation (tumor size of 0.3 cm), and mice in each tumor group were euthanized at maximum allowable size (2 cm). (A) Comparison of TM40D (CD1d-hi) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (B) Differences in rates of tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice. (C) Comparison of TM40D-MB (CD1d-lo) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. Data are mean ± SD. (D) Scatter plot depicting increased number of tumor foci counted per lung in TM40D or TM40D-MB tumor-implanted mice in immune-deficient CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (* P≤0.05, ** P<0.005, *** P≤0.001, one-way ANOVA test). Data are representative of two independent experiments.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3113806&req=5

pone-0020702-g006: Differences in tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice.Orthotopic injection into the bilateral mammary fat pads of CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice, with either 1×106 TM40D (CD1d-hi) or TM40D-MB (CD1d-lo) cells, 5 mice per tumor group. Mice were monitored for tumor formation (tumor size of 0.3 cm), and mice in each tumor group were euthanized at maximum allowable size (2 cm). (A) Comparison of TM40D (CD1d-hi) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (B) Differences in rates of tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice. (C) Comparison of TM40D-MB (CD1d-lo) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. Data are mean ± SD. (D) Scatter plot depicting increased number of tumor foci counted per lung in TM40D or TM40D-MB tumor-implanted mice in immune-deficient CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (* P≤0.05, ** P<0.005, *** P≤0.001, one-way ANOVA test). Data are representative of two independent experiments.

Mentions: For these experiments, we first compared rates of tumor growth and metastasis of TM40D (CD1d-hi) cells implanted in wildtype, CD1d KO, Jα18 KO and RAG2 KO mice. Tumor growth rates were found to be similar between wildtype and immune-deficient mouse groups (Fig. 6A). These results are in line with previous observations in the CD1d-deficient 4T1 breast cancer mouse model [37]. In contrast to rates of tumor growth, significant differences were found between these mouse groups in their ability to spontaneously metastasize to lung (Fig. 6B,D). TM40D cells were most metastatic in RAG2 KO mice, lacking adaptive immune NKT, T and B lymphocytes, but maintaining NK cell innate immune functions. These results suggest that innate NK-mediated antitumor immunity is not sufficient to inhibit spontaneous metastasis, and adaptive immune lymphocytes are the primary effector cells in our model. Next we addressed the role of CD1d-restricted NKT cells in preventing metastasis. As compared to TM40D in wildtype, the rate of metastasis and overall number of metastases per lung in TM40D-implanted CD1d KO mice was significantly higher (P = 0.0077). These results demonstrate the importance of CD1d-restricted NKT cells in regulating metastatic progression of CD1d-expressing tumors. We predicted that TM40D tumors implanted in type I NKT-deficient Jα18 KO mice would show similar rates of metastasis as compared to CD1d KO mice, owing to the importance of type I NKT cells in antitumor immunity. Surprisingly, we found a more significant increase in the rate and frequency of lung metastases in TM40D-implanted CD1d KO mice than in the Jα18 KO mice (P = 0.0164). These results establish the importance of adaptive immunity and CD1d-restricted NKT cells in preventing metastatic cancer progression of CD1d-expressing tumors, but do not directly implicate the importance of type I NKT cells in this model.


CD1d-expressing breast cancer cells modulate NKT cell-mediated antitumor immunity in a murine model of breast cancer metastasis.

Hix LM, Shi YH, Brutkiewicz RR, Stein PL, Wang CR, Zhang M - PLoS ONE (2011)

Differences in tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice.Orthotopic injection into the bilateral mammary fat pads of CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice, with either 1×106 TM40D (CD1d-hi) or TM40D-MB (CD1d-lo) cells, 5 mice per tumor group. Mice were monitored for tumor formation (tumor size of 0.3 cm), and mice in each tumor group were euthanized at maximum allowable size (2 cm). (A) Comparison of TM40D (CD1d-hi) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (B) Differences in rates of tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice. (C) Comparison of TM40D-MB (CD1d-lo) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. Data are mean ± SD. (D) Scatter plot depicting increased number of tumor foci counted per lung in TM40D or TM40D-MB tumor-implanted mice in immune-deficient CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (* P≤0.05, ** P<0.005, *** P≤0.001, one-way ANOVA test). Data are representative of two independent experiments.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3113806&req=5

pone-0020702-g006: Differences in tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice.Orthotopic injection into the bilateral mammary fat pads of CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice, with either 1×106 TM40D (CD1d-hi) or TM40D-MB (CD1d-lo) cells, 5 mice per tumor group. Mice were monitored for tumor formation (tumor size of 0.3 cm), and mice in each tumor group were euthanized at maximum allowable size (2 cm). (A) Comparison of TM40D (CD1d-hi) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (B) Differences in rates of tumor growth and metastasis between TM40D and TM40D-MB tumors in normal and immune deficient mice. (C) Comparison of TM40D-MB (CD1d-lo) tumor growth in CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. Data are mean ± SD. (D) Scatter plot depicting increased number of tumor foci counted per lung in TM40D or TM40D-MB tumor-implanted mice in immune-deficient CD1d KO, Jα18 KO, RAG2 KO, or wildtype BALB/c mice. (* P≤0.05, ** P<0.005, *** P≤0.001, one-way ANOVA test). Data are representative of two independent experiments.
Mentions: For these experiments, we first compared rates of tumor growth and metastasis of TM40D (CD1d-hi) cells implanted in wildtype, CD1d KO, Jα18 KO and RAG2 KO mice. Tumor growth rates were found to be similar between wildtype and immune-deficient mouse groups (Fig. 6A). These results are in line with previous observations in the CD1d-deficient 4T1 breast cancer mouse model [37]. In contrast to rates of tumor growth, significant differences were found between these mouse groups in their ability to spontaneously metastasize to lung (Fig. 6B,D). TM40D cells were most metastatic in RAG2 KO mice, lacking adaptive immune NKT, T and B lymphocytes, but maintaining NK cell innate immune functions. These results suggest that innate NK-mediated antitumor immunity is not sufficient to inhibit spontaneous metastasis, and adaptive immune lymphocytes are the primary effector cells in our model. Next we addressed the role of CD1d-restricted NKT cells in preventing metastasis. As compared to TM40D in wildtype, the rate of metastasis and overall number of metastases per lung in TM40D-implanted CD1d KO mice was significantly higher (P = 0.0077). These results demonstrate the importance of CD1d-restricted NKT cells in regulating metastatic progression of CD1d-expressing tumors. We predicted that TM40D tumors implanted in type I NKT-deficient Jα18 KO mice would show similar rates of metastasis as compared to CD1d KO mice, owing to the importance of type I NKT cells in antitumor immunity. Surprisingly, we found a more significant increase in the rate and frequency of lung metastases in TM40D-implanted CD1d KO mice than in the Jα18 KO mice (P = 0.0164). These results establish the importance of adaptive immunity and CD1d-restricted NKT cells in preventing metastatic cancer progression of CD1d-expressing tumors, but do not directly implicate the importance of type I NKT cells in this model.

Bottom Line: Tumor tolerance and immune suppression remain formidable obstacles to the efficacy of immunotherapies that harness the immune system to eradicate breast cancer.We hypothesize that breast cancer cells, through downregulation of CD1d and subsequent evasion of NKT-mediated antitumor immunity, gain increased potential for metastatic tumor progression.The results of this study emphasize the importance of determining the CD1d expression status of the tumor when tailoring NKT-based immunotherapies for the prevention and treatment of metastatic breast cancer.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.

ABSTRACT

Background: Tumor tolerance and immune suppression remain formidable obstacles to the efficacy of immunotherapies that harness the immune system to eradicate breast cancer. A novel syngeneic mouse model of breast cancer metastasis was developed in our lab to investigate mechanisms of immune regulation of breast cancer. Comparative analysis of low-metastatic vs. highly metastatic tumor cells isolated from these mice revealed several important genetic alterations related to immune control of cancer, including a significant downregulation of cd1d1 in the highly metastatic tumor cells. The cd1d1 gene in mice encodes the MHC class I-like molecule CD1d, which presents glycolipid antigens to a specialized subset of T cells known as natural killer T (NKT) cells. We hypothesize that breast cancer cells, through downregulation of CD1d and subsequent evasion of NKT-mediated antitumor immunity, gain increased potential for metastatic tumor progression.

Methodology/principal findings: In this study, we demonstrate in a mouse model of breast cancer metastasis that tumor downregulation of CD1d inhibits iNKT-mediated antitumor immunity and promotes metastatic breast cancer progression in a CD1d-dependent manner in vitro and in vivo. Using NKT-deficient transgenic mouse models, we demonstrate important differences between type I and type II NKT cells in their ability to regulate antitumor immunity of CD1d-expressing breast tumors.

Conclusions/significance: The results of this study emphasize the importance of determining the CD1d expression status of the tumor when tailoring NKT-based immunotherapies for the prevention and treatment of metastatic breast cancer.

Show MeSH
Related in: MedlinePlus