Fusobacterium nucleatum-induced imbalance in microbiome-derived butyric acid levels promotes the occurrence and development of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) ranks among the most prevalent malignant tumors globally. Recent reports suggest that Fusobacterium nucleatum (F. nucleatum) contributes to the initiation, progression, and prognosis of CRC. Butyrate, a short-chain fatty acid derived from the bacterial fermentation of soluble dietary fiber, is known to inhibit various cancers. This study is designed to explore whether F. nucleatum influences the onset and progression of CRC by impacting the intestinal metabolite butyric acid.

AIM

To investigate the mechanism by which F. nucleatum affects CRC occurrence and development.

METHODS

Alterations in the gut microbiota of BALB/c mice were observed following the oral administration of F. nucleatum. Additionally, DLD-1 and HCT116 cell lines were exposed to sodium butyrate (NaB) and F. nucleatum in vitro to examine the effects on proliferative proteins and mitochondrial function.

RESULTS

Our research indicates that the prevalence of F. nucleatum in fecal samples from CRC patients is significantly greater than in healthy counterparts, while the prevalence of butyrate-producing bacteria is notably lower. In mice colonized with F. nucleatum, the population of butyrate-producing bacteria decreased, resulting in altered levels of butyric acid, a key intestinal metabolite of butyrate. Exposure to NaB can impair mitochondrial morphology and diminish mitochondrial membrane potential in DLD-1 and HCT116 CRC cells. Consequently, this leads to modulated production of adenosine triphosphate and reactive oxygen species, thereby inhibiting cancer cell proliferation. Additionally, NaB triggers the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, blocks the cell cycle in HCT116 and DLD-1 cells, and curtails the proliferation of CRC cells. The combined presence of F. nucleatum and NaB attenuated the effects of the latter. By employing small interfering RNA to suppress AMPK, it was demonstrated that AMPK is essential for NaB’s inhibition of CRC cell proliferation.

CONCLUSION

F. nucleatum can promote cancer progression through its inhibitory effect on butyric acid, via the AMPK signaling pathway.

Head Acupuncture Plus Schuell's Language Rehabilitation for Post-Stroke Aphasia: A Systematic Review and Meta-Analysis of 32 Randomized Controlled Trials

OBJECTIVE

To evaluate the existing randomized controlled trials (RCTs) for evidence of the efficacy and safety of head acupuncture (HA) plus Schuell's language rehabilitation (SLR) in post-stroke aphasia.

METHODS

Seven databases including Embase, PubMed, Cochrane Library, Technology Periodical Database, the China National Knowledge Infrastructure, SinoMed and Wanfang Data Information Site were searched for RCTs published from database inception until November 14, 2021. RCTs that compared HA plus SLR with sham (or blank) control, acupuncture therapy alone, certain language rehabilitation therapy alone or other therapies for post-stroke aphasia were included. Data were extracted and assessed, and the quality of RCTs was evaluated. Fixed-effects model was used, with meta-inflfluence analysis, meta-regression, and regression-based sub-group analyses applied for exploration of heterogeneity. Publication bias was estimated by funnel plots and Egger's tests.

RESULTS

A total of 32 RCTs with 1,968 patients were included and 51 comparisons were conducted classified as types of strokes and aphasia. (1) For patients with aphasia after ischemic stroke, HA plus PSA showed significantly higher accumulative markedly effective rate [relative risk (RR)=1.55, 95% confidence interval (CI): 1.19-2.02, I²=0%] and accumulative effective rate (RR=1.22, 95% CI: 1.09-1.36, I²=0%). (2) For patients with comprehensive types of stroke, HA plus PSA was more effective in increasing recovery rate (RR=1.89, 95% CI: 1.39-2.56, I²=0%), accumulative markedly effective rate (RR=1.53, 95% CI: 1.36-1.72, I²=9%) and accumulative effective rate (RR=1.14, 95% CI: 1.09-1.19, I²=34%). (3) For patients with aphasia after stroke, HA plus PSA was superior to PSA alone with statistical significance in increasing recovery rate (RR=2.08, 95% CI: 1.24-3.46, I²=0%), accumulative markedly effective rate (RR=1.49, 95% CI: 1.24-1.78, I²=0%) and accumulative effective rate (RR=1.15, 95% CI: 1.06-1.24, I²=39%). (4) For patients with multiple types of aphasia, HA plus PSA also demonstrated significantly higher recovery rate (RR=1.86, 95% CI: 1.28-2.72, I²=0%), accumulative markedly effective rate (RR=1.55, 95% CI: 1.35-1.78, I²=22%), and accumulative effective rate (RR=1.17, 95% CI: 1.11-1.23, I²=41%). (5) For patients with motor aphasia after ischemic stroke, compared with PSA alone, HA plus PSA showed significantly higher accumulative markedly effective rate (RR=1.38, 95% CI: 1.06-1.79, I²=0%) and accumulative effective rate (RR=1.20, 95% CI: 1.05-1.37, I²=0%). Meta-regression analyses were performed without significant difference, and publication bias was found in some comparisons.

CONCLUSION

HA plus SLR was significantly associated with better language ability and higher effective rate for patients with post-stroke aphasia, and HA should be operated cautiously especially during acupuncture at eye and neck. (Registration No. CRD42020154475).

Hedgehog signaling contributes to bone cancer pain by regulating sensory neuron excitability in rats

Treating bone cancer pain continues to be a clinical challenge and underlying mechanisms of bone cancer pain remain elusive. Here, we reported that sonic hedgehog signaling plays a critical role in the development of bone cancer pain. Tibia bone cavity tumor cell implantation produces bone cancer-related mechanical allodynia, thermal hyperalgesia, and spontaneous and movement-evoked pain behaviors. Production and persistence of these pain behaviors are well correlated with tumor cell implantation-induced up-regulation and activation of sonic hedgehog signaling in primary sensory neurons and spinal cord. Spinal administration of sonic hedgehog signaling inhibitor cyclopamine prevents and reverses the induction and persistence of bone cancer pain without affecting normal pain sensitivity. Inhibiting sonic hedgehog signaling activation with cyclopamine, in vivo or in vitro, greatly suppresses tumor cell implantation-induced increase of intracellular Ca²⁺ and hyperexcitability of the sensory neurons and also the activation of GluN2B receptor and the subsequent Ca²⁺-dependent signals CaMKII and CREB in dorsal root ganglion and the spinal cord. These findings show a critical mechanism underlying the pathogenesis of bone cancer pain and suggest that targeting sonic hedgehog signaling may be an effective approach for treating bone cancer pain.

Sonic hedgehog signaling in spinal cord contributes to morphine-induced hyperalgesia and tolerance through upregulating brain-derived neurotrophic factor expression

Purpose

Preventing opioid-induced hyperalgesia and tolerance continues to be a major clinical challenge, and the underlying mechanisms of hyperalgesia and tolerance remain elusive. Here, we investigated the role of sonic hedgehog (Shh) signaling in opioid-induced hyperalgesia and tolerance.

Methods

Shh signaling expression, behavioral changes, and neurochemical alterations induced by morphine were analyzed in male adult CD-1 mice with repeated administration of morphine. To investigate the contribution of Shh to morphine-induced hyperalgesia (MIH) and tolerance, Shh signaling inhibitor cyclopamine and Shh small interfering RNA (siRNA) were used. To explore the mechanisms of Shh signaling in MIH and tolerance, brain-derived neurotrophic factor (BDNF) inhibitor K252 and anti-BDNF antibody were used.

Results

Repeated administration of morphine produced obvious hyperalgesia and tolerance. The behavioral changes were correlated with the upregulation and activation of morphine treatment-induced Shh signaling. Pharmacologic and genetic inhibition of Shh signaling significantly delayed the generation of MIH and tolerance and associated neurochemical changes. Chronic morphine administration also induced upregulation of BDNF. Inhibiting BDNF effectively delayed the generation of MIH and tolerance. The upregulation of BDNF induced by morphine was significantly suppressed by inhibiting Shh signaling. In naïve mice, exogenous activation of Shh signaling caused a rapid increase of BDNF expression, as well as thermal hyperalgesia. Inhibiting BDNF significantly suppressed smoothened agonist-induced hyperalgesia.

Conclusion

These findings suggest that Shh signaling may be a critical mediator for MIH and tolerance by regulating BDNF expression. Inhibiting Shh signaling, especially during the early phase, may effectively delay or suppress MIH and tolerance.

[Copy number aberrations of genes related to extrohepatic metastasis-free survival after operation for hepatocellular carcinoma]

Objective: To investigate the molecular markers of copy number aberrations (CNAs) of genes related to extrohepatic metastasis-free survival after the operation for hepatocellular carcinoma (HCC). Methods: The CNA status of 20 candidate genes in 66 HCC samples was detected by microarray comparative genomic hybridization. The associations between gene CNAs and extrohepatic metastasis-free survival were evaluated using the Cox regression model, Log-rank test, and Kaplan-Meier survival analysis. Results: Multivariate Cox analysis revealed that the independent risk factors for metastasis-free survival were MDM4 gain (hazard ratio [HR] = 2.74, 95% confidence interval [CI] = 1.18-6.37, P < 0.05), APC loss (HR = 8.43, 95% CI = 2.48-28.66, P < 0.01), and BCL2L1 gain (HR = 3.45, 95% CI = 1.13-10.52, P < 0.05) and the independent protective factor was FBXW7 loss (HR = 0.32, 95% CI = 0.12-0.89, P < 0.05). By stepwise Cox regression analysis, three CNAs related to metastasis-free survival were screened out: MDM4 gain (HR = 2.71, 95% CI = 1.11-6.64, P < 0.05), APC loss (HR = 7.19, 95% CI = 1.88-27.60, P < 0.005), and FBXW7 loss (HR = 0.16, 95% CI = 0.05-0.46, P < 0.01). There were significant differences in metastasis-free survival rate between the HCC patients with FBXW7 loss and without MDM4 gain or APC loss, those with MDM4 gain and/or APC loss and without FBXW7 loss, and those with other CNA combinations (log-rank test, P < 0.01). Conclusion: MDM4 gain, APC loss, and FBXW7 loss are the independent prognostic factors for extrohepatic metastasis-free survival after the operation for HCC and can be used to predict the risk of extrohepatic metastasis after the operation for HCC.