Suitability of Stimuli evoked Hypersensitivities in Hind paws as a Clinically Relevant Pain Behavioural Measure in Rat Model of Walker 256 Breast Cancer Cellinduced Bone Pain: An Overview

Priyank A Shenoy

doi:10.21767/2393-8862.100014

Abstract

Metastases of breast cancer cells to the axial skeleton causes excruciating pain. The nature of pain hypersensitivities in metastasized bones is very complex due to the interplay of inflammatory, neuropathic and cancer-specific pain components. The existing drugs typically used to treat breast cancer-induced bone pain are inefficacious and often exhibit severe side effects. Hence, it remains to be an important goal of the ongoing research activities to seek novel analgesic compounds with better efficacy and tolerability. One of the key aspects in the process of understanding the mechanisms of pain progression and drug discovery to mitigate the hypersensitivities is employment of suitable preclinical animal models that mimic the complex human pathophysiology of breast cancer induced bone pain. Walker 256 breast cancer cell- induced bone pain model in rats is one such model that is known to show key resemblances to the clinical pain associated with bony metastases. The commonly used methods to assess pain hypersensitivities in Walker 256 cell- induced bone pain model in rats include stimuli evoked techniques like von Frey assessment and Randall-Selitto test. While other methods like assessment of gait parameters or spontaneous pain can also be used as beneficial complementary tools, this short review majorly sheds light on suitability of the stimuli evoked pain assessment methods in the hind paws of rats as being clinically relevant measures of assessing breast cancer induced bone pain in Walker 256 cell induced bony metastases.

Highlights

Pain is a significant medical problem that co-exists with several diseases including various types of cancer [1]
Breast cancer cells metastasize from the tissue of origin and establish themselves in distant parts of the axial skeleton [2]
Selitto testing using increasing force delivered via a blunt cone shaped pusher, are two of the most common behavioural tests employed in assessment of Walker 256 cell induced Breast cancer-induced bone pain (BCIBP) in rats [9]

Summary

Introduction

Pain is a significant medical problem that co-exists with several diseases including various types of cancer [1]. The existing analgesic/adjuvant medications are often insufficiently efficacious to combat this pain condition [5-. It is very important to develop and characterize suitable preclinical models of BCIBP so as to assist in drug discovery programs aimed at identifying novel compounds having potential to mitigate this often intractable pain condition. The rat model of Walker 256 breast cancer cell induced bone pain is a highly useful preclinical tool for assessment of mechanisms of BCIBP and for seeking novel analgesics in the treatments thereof, as it mimics key aspects of the human pathophysiology of this condition [8,9,10,11]

Discussion

Conclusion