Immunization against leukemia inhibitory factor and its receptor suppresses tumor formation of breast cancer initiating cells in BALB/c mouse

Abstract

Immunotherapy is a promising approach for specific targeting of cancer cells. Leukemia inhibitory factor (Lif) regulates several features of cancers and cancer stem cells (cScs) through binding to Lif receptor (LIFR). In this study, we investigated the consensus of LIF and LIFR immunization on the growth of mouse mammary tumors. For this purpose, mouse LIF and LIFR were designed as truncated proteins, expressed in E. coli and then injected to mice as individual and mixed antigens. The results showed the production of neutralizing antibodies and secretion of interferon-γ and interleukin-2 in response to immunization. In continue, the immunized mice were subjected for tumor formation challenge by inoculation of the breast CSCs derived from MC4-L2 cells. Development of the breast tumors was observed in all the control mice, while the tumors appeared in 75% of animals in the LIF group. LIFR injection, individually or in combination with LIF, strongly inhibited the tumor growth to only 25% of the mice. Moreover, a delay in tumor appearance was observed in the immunized mice compared to the controls. Immunostaining of the tumor sections confirmed the expression of LIF and LIFR. In conclusion, LIF and LIFR might be effective targets for immunotherapy of the tumors that express these proteins. Breast cancer is the most frequently occurring cancer in females. Resistance to therapy and recurrence of disease are two barriers restricting treatment of breast cancer. Novel highly efficient and specific therapeutic approaches causing lower toxicity have to be emerged to overcome these obstacles. Immunotherapy against tumors is an invaluable approach in this regard, which stimulates strong highly specific humoral and cellular immune responses 1-3. Leukemia inhibitory factor (LIF) is a pleiotropic protein belonging to the interleukin-6 family cytokines. It is a highly conserved secretory glycoprotein among different species. There is approximately 80% homology between amino acid sequences of human and mouse LIF. This multi-functional cytokine is necessary for maintaining pluripotency state of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) 4-6. LIF was identified according to its action on inhibition of mouse myeloid leukemia cells growth and induction of differentiation. LIF also displays several functions on development and progression of cancers. LIF elicits proliferation of different kinds of cancers such as multiple myeloma, colon, prostate and breast cancers 7,8. LIF upregulation causes tumor resistance to chemotherapy in colorectal cancer. Nasopharyngeal carcinomas with increased level of LIF showed higher rate of growth and radioresistance 9,10. Wysoczynski et al. 11 showed that LIF-responsive rhabdomyosarcoma could metastasize to lung several weeks after injection. LIF exerts its actions through binding to LIF receptor (LIFR) located on cell surface. LIFR is a heterodimeric receptor comprised of LIFRβ and gp130 subunits. LIF first binds to LIFRβ subunit and then to gp130 and makes a functional comp...

Plasma proteomics identifies leukemia inhibitory factor (LIF) as a novel predictive biomarker of immune-checkpoint blockade resistance

“…24 Interestingly, LIF neutralization was associated with strong inhibition of tumor growth in several preclinical models. 25,26 A recent study has also shown that LIF blockade is associated with an increased production of CXCL9 by macrophages and a concomitant decrease in CD206, CD163 and CCL2. 26 In our study, while baseline plasma LIF was associated with an intratumoral expression of LIF, no correlation was found for either CCL2, CD206 or CXCL9 (Supplementary Figure S6 We therefore assessed whether the peripheral level of LIF was associated with specific tumor microenvironment features.…”

Cancer-educated mammary adipose tissue-derived stromal/stem cells in obesity and breast cancer: spatial regulation and function

“…Moreover, the expression of LIF in the stroma was significantly elevated in breast cancer tissue sections from lean patients. Interestingly, the high expression of LIF has been connected to increased tumor progression, stemness, therapy resistance and TME modulation in various cancer entities in multiple in vitro and in vivo models [ 98 ] and the immunization against LIF or LIFR suppressed the tumor formation, growth and metastasis in a mammary xenograft mouse model [ 99 ]. Our findings clearly suggest that obesity influences the TME.…”

Elevated expression of LIF predicts a poor prognosis and promotes cell migration and invasion of clear cell renal cell carcinoma

“…This promotion occurs through the activation of AKT, which activates the downstream mTOR signaling pathway ( 24 ). At the same time, LIF was reversed to promote tumor formation and metastasis ( 25 ). However, the role of LIF in ccRCC has not been studied.…”