Pharmacologic Management of Cancer-Related Pain in Pregnant Patients

Exploring the novel role and mechanistic insights of skeletal muscle relaxant cyclobenzaprine hydrochloride in esophageal squamous cell carcinoma treatment

OBJECTIVE

Cyclobenzaprine hydrochloride (Flexeril) is a muscle relaxant primarily used to relieve muscle pain and spasms. However, its potential anti-cancer role remains largely unexplored. This study aims to investigate the inhibitory effect of Flexeril on esophageal squamous cell carcinoma (ESCC) and to uncover the molecular mechanisms through which it affects the proliferation and metastasis of ESCC.

METHODS

A compound library approved by the FDA was employed to screen drugs with inhibitory effects on ESCC. Cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay, and Plate colony formation was analyzed to evaluate the proliferative ability of ESCC cell lines (KYSE150 and Eca109) after treatment with Flexeril. Migratory ability was examined through Transwell and Scratch assays. Proteomics was performed to identify proteins regulated by Flexeril in KYSE150 and Eca109 cells. RT-PCR and Western blot were used to detect changes in related genes at the mRNA and protein levels after treatment with Flexeril. Drug affinity responsive target stability (DARTS) assay and cellular thermal shift assay (CETSA) were employed to identify the binding of Flexeril and JAK1 protein. Additionally, the comet assay was conducted to assess the DNA damage response in ESCC cells following WDHD1 knockdown or Flexeril exposure. Finally, tumor‑bearing nude mice model were constructed to evaluate the in vivo anticancer effects of Flexeril on ESCC.

RESULTS

Flexeril significantly inhibited the proliferation and migration of ESCC cells in a time- and dose-dependent manner. Proteomics analysis identified WDHD1 as a downstream target of Flexeril exposure, and knockdown of WDHD1 mimicked the effects of Flexeril on proliferation and migration of ESCC. Conversely, overexpression of WDHD1 attenuated the inhibitory effects of Flexeril on ESCC. Mechanistically, the JAK1-STAT3 signaling pathway, but not the JAK2-STAT3 or PI3K-Akt-mTOR pathways, was involved in regulating WDHD1 expression in ESCC cells following Flexeril treatment. Overexpression of STAT3 or WDHD1 mitigated the inhibitory effects of Flexeril on ESCC proliferation and migration. Moreover, both Flexeril exposure and WDHD1 knockdown induced a DNA damage response (DDR) in ESCC cells. In addition, Flexeril significantly inhibited the growth of ESCC tumors in nude mice, downregulating the JAK1-STAT3-WDHD1 signaling pathway, with no significant damage observed in vital organs such as the heart, liver, spleen, lungs, or kidneys, as shown by histological examination.

CONCLUSION

Flexeril exhibits anti-cancer effects in ESCC by inhibiting the JAK1-STAT3-WDHD1 axis and inducing DDR. These findings suggest that Flexeril may serve as a potential novel therapeutic agent for the treatment of ESCC.

Cancer-Related Pain Management in Pregnancy-A Review

Background: Cancer-related pain management in pregnant patients is a complex clinical challenge requiring a careful balance between effective maternal analgesia and fetal safety. The pathophysiology of cancer-related pain varies, necessitating a nuanced, individualized approach to treatment with careful consideration of maternal-fetal safety, and pharmacokinetics. Objectives: This review aims to explore safe and effective pharmacological and interventional strategies for managing cancer-related pain in pregnant patients while highlighting disparities in access to care. Design: A comprehensive literature review was conducted. A total of 4766 articles were identified, with 98 studies included for final analysis after exclusion. Setting/Subjects: Studies included pregnant individuals with various hematological and solid tumor malignancies across various community and academic settings. Measurements: Pain typology was categorized (nociceptive or neuropathic), with treatment options including commonly available over-the-counter medications, opioids, various neuropathic medications, and interventional pain management options. In addition to pharmacological efficacy and maternofetal safety profiles, interventional efficacy, and socio-cultural influences on care were also measured. Disparities in access to care were also analyzed. Results: Analgesic options in pregnancy include acetaminophen, opioids, certain neuropathic medications, with very cautious use of NSAIDs. Interventional methods-neuraxial anesthesia, nerve blocks, spinal cord stimulation-offer adjunctive benefit if done under ultrasound guidance, but fluoroscopy and radiation guided modalities are best avoided in pregnancy. Diverse populations often encountered significant barriers to adequate pain control. Conclusions: Optimal cancer pain management in pregnancy necessitates a multidisciplinary, and individually tailored approach. Enhancing clinical evidence, and ensuring culturally competent care are critical to improving outcomes in this patient population.

Unique Characteristics of Stroke in Women and Rehabilitation Considerations

Stroke is the third leading cause of death of women in the United States, and women have a higher lifetime risk of stroke than men. Studies show that women live longer but with poorer functional outcomes and higher rates of disability compared with men. Sex-specific disparities exist between clinical symptoms, medical evaluation, and management after stroke. Stroke rehabilitation strategies specific to women should take into consideration both physiologic and psychosocial demands more common in women to improve functional outcomes. Additional resources for education, clinical research, and implementation of best practices are needed to eliminate gender-related disparities in poststroke care.

Anwulignan Alleviates Bone Cancer Pain by Modulating the PPARα/CXCR2 Signaling Pathway in the Rat Spinal Cord

AIMS

Advanced cancer patients frequently endure severe pain from bone metastases, and few effective treatments for bone cancer pain (BCP) exist. Although Anwulignan is known for its antioxidant, anti-inflammatory, and antitumor properties, its effects on BCP remain unclear. This study aims to explore the analgesic effects and mechanisms of Anwulignan on bone cancer pain.

METHODS

Western blotting and immunofluorescence assessed molecular expression and localization. X-ray, micro-CT, TRAP, and ALP staining examined bone destruction in rats. MTT, colony formation assays, and in vivo imaging analyzed tumor changes. RNA-Seq identified differentially expressed genes, validated by ChIP analysis.

RESULTS

Here, we showed that Anwulignan alleviated mechanical, thermal, and cold hypersensitivity and spontaneous pain, prevented bone destruction, and suppressed local tumor growth in rats with BCP. Furthermore, Anwulignan was firmly bound to proliferator-activated receptor alpha (PPARα), increasing its thermal stability. Intrathecal (i.t.) injection of PPARα siRNA increased pain sensitivity in naive rats, and PPARα siRNA abrogated the analgesic effect of Anwulignan in BCP model rats. Moreover, the PPARα agonist pirinixic acid reduced BCP hypersensitivity and abrogated the upregulation of CXC chemokine receptor 2 (CXCR2). Importantly, PPARα bound to the CXCR2 promoter region, and Anwulignan could reverse the reduced binding of PPARα to CXCR2 caused by BCP.

CONCLUSION

Taken together, these results indicate that Anwulignan is a potential antitumor and analgesic agent that exerts its effects via upregulation of PPARα expression to inhibit the expression of CXCR2 and could be used for treating BCP.

Molecular Mechanisms and Therapeutic Potential of Gabapentin with a Focus on Topical Formulations to Treat Ocular Surface Diseases

Gabapentin (GBP) was originally developed as a potential agonist for Gamma-Amino-Butyric-Acid (GABA) receptors, aiming to inhibit the activation of pain-signaling neurons. Contrary to initial expectations, it does not bind to GABA receptors. Instead, it exhibits several distinct pharmacological activities, including: (1) binding to the alpha-2-delta protein subunit of voltage-gated calcium channels in the central nervous system, thereby blocking the excitatory influx of calcium; (2) reducing the expression and phosphorylation of CaMKII via modulation of ERK1/2 phosphorylation; (3) inhibiting glutamate release and interfering with the activation of NMDA receptors; (4) enhancing GABA synthesis; (5) increasing cell-surface expression of δGABA_A receptors, contributing to its antinociceptive, anticonvulsant, and anxiolytic-like effects. Additionally, GBP displays (6) inhibition of NF-kB activation and subsequent production of inflammatory cytokines, and (7) stimulation of the purinergic adenosine A1 receptor, which supports its anti-inflammatory and wound-healing properties. Initially approved for treating seizures and postherpetic neuralgia, GBP is now broadly used for various conditions, including psychiatric disorders, acute and chronic neuropathic pain, and sleep disturbances. Recently, as an eye drop formulation, it has also been explored as a therapeutic option for ocular surface discomfort in conditions such as dry eye, neurotrophic keratitis, corneal ulcers, and neuropathic ocular pain. This review aims to summarize the evidence supporting the molecular effects of GBP, with a special emphasis on its applications in ocular surface diseases.

Frontline Perspectives on Buprenorphine for the Management of Chronic Pain

Due to the prevalence of chronic pain and high-impact chronic pain in the US, a significant percentage of the population is prescribed opioids for pain management. However, opioid use disorder is associated with reduced quality of life, along with fatal opioid overdoses, and is a significant burden on the US economy. Considering the clinical needs of patients with intractable chronic pain and the potential harms associated with prescribed and illicit opioids in our communities, having a deep understanding of current treatment options, supporting evidence, and clinical practice guidelines is essential for optimizing treatment selections. Buprenorphine is a Schedule III opioid with a unique mechanism of action, allowing effective and long-lasting analgesia at microgram doses with fewer negative side effects and adverse events, including respiratory depression, when compared with other immediate-release, long-acting, and extended-release prescription opioids. Due to its relatively lower risk for overdose and misuse, buprenorphine was recently added to the Clinical Practice Guideline for the Use of Opioids in the Management of Chronic Pain as a first-line treatment for chronic pain managed by opioids by the US Departments of Defense and Veterans Affairs, and the Department of Health and Human Services recommends that buprenorphine be made available for the treatment of chronic pain. In this narrative review, we discuss the different buprenorphine formulations, clinical efficacy, advantages for older adults and other special populations, clinical practice guideline recommendations, and payer considerations of buprenorphine and suggest that buprenorphine products approved for chronic pain should be considered as a first-line treatment for this indication.