Leptin-induced signaling pathways in cancer cell migration and invasion

BACKGROUND

Increasing evidence indicates that obesity is associated with tumor development and progression. Leptin is an adipocyte-related hormone with a key role in energy metabolism and whose circulating levels are elevated in obesity. The effect of leptin on cancer progression and metastasis and its underlying mechanisms are still unclear. Leptin can impact various steps in tumor metastasis, including epithelial-mesenchymal transition, cell adhesion to the extracellular matrix (ECM), and proteolysis of ECM components. To do so, leptin binds to its receptor (OB-Rb) to activate signaling pathways and downstream effectors that participate in tumor cell invasion as well as distant metastasis.

CONCLUSIONS

In this review, we describe metastasis steps in detail and characterize metastasis-related molecules activated by leptin, which may help to develop a roadmap that guides future work. In addition, we conclude that a profound understanding of the fundamental molecular processes that contribute to leptin-induced metastasis may pave the way for the development of new prognostic molecules and appropriate approaches to the treatment of obesity-related cancers.

Assessment of leptin and resistin levels in non-obese multiple myeloma patients and their relation with Ig level and disease stage

INTRODUCTION

Multiple myeloma (MM) accounts for approximately 0.8% of all cancer diagnoses and 0.9% of cancer deaths. Leptin receptors were expressed on CD34(+) cells. Resistin receptors were expressed on inflammatory cells and pro-inflammatory cytokines increase the expression of resistin on monocytes.

AIM OF WORK

To assess the level of leptin and resistin in non-obese multiple myeloma patients and to study their relation with Ig level and disease stage.

SUBJECTS & METHODS

32 subjects were included; 16 patients diagnosed with MM and 16 healthy individuals served as control. All were subjected to history taking, clinical examination, routine laboratory investigations and leptin & resistin blood level. Laboratory investigations were done for diagnosis and staging for MM patients.

RESULTS

Leptin was significantly higher in MM patients compared with the control group, unlike resistin which showed no significant difference between the two groups. A significant positive relation was found between IgG level & leptin. Similarly, a significant difference in leptin level has been observed between stage I & stage II (higher in II).

CONCLUSIONS

Leptin may play a role in the pathogenesis of MM and its level may be changed in different stages.