Clinical and genetic factors related to cancer-induced bone pain and bone pain relief

LncRNA NONRATT014888.2 contributes to cancer-induced bone pain through downregulation of natriuretic peptide receptor 3 in rats

Long noncoding RNA (lncRNA) is implicated in both cancer development and pain process. However, the role of lncRNA in the development of cancer-induced bone pain (CIBP) is unclear. LncRNA NONRATT014888.2 is highly expressed in tibia related dorsal root ganglions (DRGs) in CIBP rats which function is unknown. CIBP was induced by injection of Walker 256 mammary gland tumor cells into the tibia canal of female SD rats. Paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) of rats were measured. Down-regulation of NONRATT014888.2 by siRNA in CIBP rats markedly attenuated hind-paw mechanical pain hypersensitivity. LncRNA-predicted target mRNAs analysis and mRNA sequencing results cued Socs3, Npr3 were related with NONRATT014888.2. Intrathecal injection of NONRATT014888.2-siR206 upregulated Npr3 both in mRNA and protein level. Npr3 was co-expressed in NONRATT014888.2-positive DRGs neurons and mainly located in cytoplasm, but not in Glial fibrillary acidic protein (GFAP)-positive cells. Intrathecal injection of ADV-Npr3 upregulated Npr3 expression and enhanced the PWT of CIBP rats. Our results suggest that upregulated lncRNA NONRATT014888.2 contributed to hyperalgesia in CIBP rats, and the mechanism may through downregulation of Npr3.

Genetic and Clinical Factors Associated with Opioid Response in Chinese Han Patients with Cancer Pain: An Exploratory Cross-Sectional Study

Introduction

Studies have shown that genetic variation and environmental factors are associated with individual differences in therapeutic efficacy and side effects of opioids. However, the focus of these studies has been on a single factor of single-nucleotide polymorphisms (SNPs) or haplotypes, for which results have rarely been validated. For complex traits, such as cancer pain and opioid response, interactions between multiple genetic variation and environmental factors need to be considered to explain the opioid individual differences.

Methods

We conducted an exploratory two-stage cross-sectional study with 1027 Chinese patients who were taking strong opioid medications for their cancer pain, and genotyped 110 SNPs to explore the association of SNPs, haplotypes, gene–gene and gene–environment interactions with opioid dose, pain relief, and opioid-induced constipation.

Results

Due to the failure to meet Benjamini–Hochberg criteria in the discovery stage or to be validated in replication stage, no association was found between SNPs, haplotypes, paired SNP–SNP interactions or multi-dimensional gene–gene interactions and opioid response. However, for gene–environment interactions, optimal models have been constructed in all phenotypes of opioid response.

Conclusions

This study reveals for the first time that construction of multidimensional gene–environment interactions enables better interpretations of the effect of genetic variation and environmental factors on the opioid response in patients with cancer pain.

Trial registration

Chictr.org.cn, identifier, ChiCTR2000033576.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-022-00353-5.

Identification of lncRNA and mRNA expression profiles in dorsal root ganglion in rats with cancer-induced bone pain

BACKGROUND

Cancer-induced bone pain (CIBP) is one of the most severe types of chronic pain which the involved mechanisms are largely unknown. LncRNA has been found to play critical roles in chronic pain. However, its function in peripheral nervous system in CIBP remains unknown. Identifying the different lncRNA expression pattern is essential for understanding the genetic mechanisms underlying the pathogenesis of CIBP.

METHODS

The model was induced by injection of Walker 256 cells into the rat tibia canal. Behavior tests and X-ray microtomography (MicroCT) analysis were performed to verify the model's establishment. L2-L5 DRGs were harvested at 14-day post operation and the differential lncRNA and mRNA expression patterns were investigated by microarray analyses. RT-qPCR analysis and RNA interference were performed for expression and function verifications. Bioinformatics analysis was conducted for further function study.

RESULTS

CIBP rats showed hyperalgesia and the MicroCT analysis showed tibia destruction. A total of 73 lncRNAs and 187 mRNAs were dysregulated. The expressions of several lncRNAs and mRNAs were validated by RT-qPCR experiment. Biological analyses showed that the changed mRNAs were mainly related to cellular and single-organism process, cell and cell part, binding function and immune system pathway. The top 30 lncRNA-predicted mRNAs are mainly related to peroxisome, DNA-dependent DNA replication, double-stranded RNA binding, tuberculosis and purine metabolism. 56 lncRNAs (30 downregulated and 26 upregulated) and 179 DEGs (35 downregulated and 144 upregulated) have a significant correlation and constructed a co-expression network. Downregulation of lncRNA NONRATT021203.2 by siRNA intrathecal injection increased PWL and WBD in CIBP rats, alleviating cancer induced bone hyperalgesia.

CONCLUSION

LncRNA played important roles in regulation of CIBP or mRNA expression in peripheral neuropathy in CIBP. These alterd mRNAs and lncRNAs might be potential therapeutic targets for the treatment of CIBP.

Sensitization of Cutaneous Primary Afferents in Bone Cancer Revealed by In Vivo Calcium Imaging

Simple Summary

Cancer-induced bone pain severely impairs the quality of life of cancer patients, many of whom suffer from inadequate pain relief. The development of new analgesic therapies depends on the identification of the cells and mechanisms involved in cancer-induced bone pain. Bone marrow innervating sensory neurons have been proposed to contribute to this debilitating disease, but their role remains unexplored. Here we used in vivo calcium imaging to determine the functional role of bone innervating and skin innervating neurons in contributing to pain at an advanced stage of bone cancer. Our results indicate increased excitability of skin innervating neurons, while those innervating bone are unaffected. Our data suggests skin-innervating neurons become hyperexcitable in cancer-induced bone pain and are a potential target for pain relief.

Abstract

Cancer-induced bone pain (CIBP) is a complex condition, comprising components of inflammatory and neuropathic processes, but changes in the physiological response profiles of bone-innervating and cutaneous afferents remain poorly understood. We used a combination of retrograde labelling and in vivo calcium imaging of bone marrow-innervating dorsal root ganglia (DRG) neurons to determine the contribution of these cells in the maintenance of CIBP. We found a majority of femoral bone afferent cell bodies in L3 dorsal root ganglia (DRG) that also express the sodium channel subtype Na_v1.8—a marker of nociceptive neurons—and lack expression of parvalbumin—a marker for proprioceptive primary afferents. Surprisingly, the response properties of bone marrow afferents to both increased intraosseous pressure and acid were unchanged by the presence of cancer. On the other hand, we found increased excitability and polymodality of cutaneous afferents innervating the ipsilateral paw in cancer bearing animals, as well as a behavioural phenotype that suggests changes at the level of the DRG contribute to secondary hypersensitivity. This study demonstrates that cutaneous afferents at distant sites from the tumour bearing tissue contribute to mechanical hypersensitivity, highlighting these cells as targets for analgesia.

Which factors can aid clinicians to identify a risk of pain during the following month in patients with bone metastases? A longitudinal analyses

PURPOSE

Explore clinical factors associated with higher pain intensity and future pain in patients with bone metastases to identify patients who can benefit from closer follow-up or pain-modifying interventions.

METHODS

This is a secondary analysis of 606 patients with bone metastases included in a multicenter longitudinal study. The dependent variables were "average pain" and "worst pain" in the last 24 h (0-10 NRS). Twenty independent variables with potential association to pain intensity were selected based on previous literature. Cross-sectional analyses were performed with multiple linear regression to explore factors associated with pain intensity at baseline. Longitudinal data were analyzed with a generalized equation models to explore current factors associated with pain intensity at the next visit in 1 month.

RESULTS

Current pain intensity (p < 0.001), sleep disturbances (p 0.01 and 0.006), drowsiness (p 0.003 and 0.033) and male gender (p 0.045 and 0.001) were associated with higher average and worst pain intensity in 1 month. In addition, breakthrough pain was related to higher worst pain intensity (p 0.003) in 1 month. The same variables were also associated with higher average pain intensity at baseline.

CONCLUSION

Higher current pain intensity, sleep disturbances, drowsiness, male gender, and breakthrough pain are factors associated with higher pain intensity in patients with bone metastases at the next follow-up in 1 month. These factors should be assessed in clinical practice and may aid clinicians in identifying patients that can benefit from closer follow-up or interventions to prevent lack of future pain control. TRIAL REGISTRATION IN CLINICALTRIALS.GOV : NCT01362816.

Assessing the impact of pain on the life of breast cancer survivors using the Brief Pain Inventory

[Purpose] This study attempted to assess the impact of pain on the life of breast cancer survivors using the Brief Pain Inventory (BPI). [Subjects and Methods] A cross-sectional study was conducted. Participants comprised 30 women, aged 30-80 years, who had received treatment for breast cancer (surgery and complementary treatment) at least 12 months prior to the study and had reported chronic pain related to the treatment procedures. [Results] The highest scores were found for "mood" (median: 5.00 points; first quartile: 1.00 points; third quartile: 7.25 points), "normal work" (median: 5.00 points; first quartile: 0.00 points; third quartile: 8.00 points), and "sleep" (median: 4.50 points, first quartile: 0.00 points, third quartile: 8.00 points). [Conclusion] Pain exerts a negative impact primarily on mood, normal work, and sleep among breast cancer survivors.