The pathobiology of mucositis

Dual-functional guanosine-based hydrogel: high-efficiency protection in radiation-induced oral mucositis

Radiation-induced oral mucositis (RIOM) is the most common adverse effect experienced by cancer patients following radiotherapy; however, effective clinical treatments remain insufficiently recognized. In this study, a guanosine-polyvinyl alcohol (G-PVA) supramolecular hydrogel was developed using a one-pot synthesis method. The G-PVA hydrogel demonstrated remarkable wet adhesion properties measuring 74.16 kPa (±3.53 kPa), biocompatibility and shape adaptability, making it suitable for the dynamic conditions of the oral cavity. Under radiation exposure, the G-PVA hydrogel not only mitigated oxidative stress but also provided effective protection to cells against direct damage, as shown by the decrease in the number of γ-H2AX foci from 79.81% (±1.33%) to 5.70% (±0.88%) and 17.12% (±3.44%), respectively. In vivo investigations further validated that the G-PVA hydrogel significantly reduced RIOM, with a decrease in the relative ulcerative area by 52.23% in comparison to the IR group. This dual-functional supramolecular hydrogel may represent a promising new clinical strategy for the prevention of RIOM in the future.

Causes and management of acute oncological pain: a narrative review

INTRODUCTION

Acute pain in cancer is an important but often overlooked feature of many patients' oncological journey. Cancer-related pain is associated commonly with more persistent pain states caused by both the disease and its treatment, but there are numerous causes of acute pain which can develop in patients with cancer. This pain is frequently severe, can be challenging to manage and its suboptimal control can directly impact on oncological outcomes. This narrative review provides an overview of several causes of acute pain in patients with cancer and management approaches.

METHODS

A focused literature review was conducted to encompass the search terms 'acute pain', 'oncology' and 'cancer' in adult and paediatric populations.

RESULTS

Acute pain is common in patients with cancer with a number of pain generators identified. Broadly, these are disease- and treatment-related but commonality in pain mechanisms and features are present. Importantly, these pain states do not occur in isolation; a patient may experience multiple acute pain episodes during their oncology journey.

DISCUSSION

As the oncological treatment landscape shifts and increasing numbers of novel treatments are employed, the number of causes of acute pain in patients with cancer rises. This pain is often managed by non-pain specialists and suboptimal control has a variety of deleterious effects. It is important that awareness of acute pain in the oncological population is increased and treatment approaches, which adopt a biopsychosocial structure, are optimised.

Normal tissue complication probability model for acute oral mucositis in patients with head and neck cancer undergoing carbon ion radiation therapy based on dosimetry, radiomics, and dosiomics

BACKGROUND AND PURPOSE

To develop a normal tissue complication probability (NTCP) model for predicting grade ≥ 2 acute oral mucositis (AOM) in head and neck cancer patients undergoing carbon-ion radiation therapy (CIRT).

METHODS AND MATERIALS

We retrospectively included 178 patients, collecting clinical, dose-volume histogram (DVH), radiomics, and dosiomics data. Patients were randomly divided into training (70%) and test sets (30%). Feature selection involved univariable logistic regression, least absolute shrinkage and selection operator regression, stepwise backward regression, and Spearman's correlation test, with the bootstrap method ensuring reliability. Multivariable models were built on the training set and evaluated using the test set.

RESULTS

The optimal NTCP model incorporated a DVH parameter (V37Gy [relative biological effectiveness, RBE]), radiomics, and dosiomics features, achieving an area under the curve (AUC) of 0.932 in the training set and 0.959 in the test set. This hybrid model outperformed those based on single DVH, radiomics, dosiomics, or clinical data (Bonferroni-adjusted p < 0.001 and ΔAUC > 0 for all comparisons in 1,000 bootstrap validations). Calibration curves showed strong agreement between predictions and outcomes. A 44.0 % AOM risk threshold was proposed, yielding accuracies of 87.1 % in the training set and 90.7 % in the test set.

CONCLUSIONS

We developed the first NTCP model for estimating AOM risk in head and neck cancer patients undergoing CIRT and proposed a risk stratification. This model may assist in clinical decision-making and improve treatment planning for AOM prevention and management by identifying high-risk patients.

Managing strategies of chemotherapy and radiotherapy-induced oral mucositis

Radiotherapy and chemotherapy are widely employed as primary non-surgical cancer treatments; however, their non-selective cytotoxicity often leads to adverse events such as oral mucositis (OM), particularly in head and neck cancer therapies. International guidelines provide recommendations for managing chemoradiotherapy-induced OM in various clinical contexts. Subsequently, emerging researches have introduced evidence supporting novel approaches or existing regimens for OM prevention and treatment. The repurposing of established drugs has garnered significant interest due to its shorter development timeline, improved safety profiles, and lower costs compared to new drug development. For example, clinical trials assessing established drugs such as melatonin, clonidine, and pentoxifylline indicate promising potential for managing OM. Additionally, several emerging pharmacological interventions have demonstrated considerable efficacy; SAMITAL and rhIL-11 are supported by phase II clinical trials and prospective studies, while probiotics like Streptococcus salivarius K12 and curcumin have shown effectiveness in randomized clinical trials. Furthermore, recent high-level studies have reinforced the efficacy of non-pharmacological interventions, such as photobiomodulation (PBM) and cryotherapy, over the past two years. In all, given the evidence supporting different strategies, PBM and oral cryotherapy are highly recommended for managing OM when feasible. Topical clonidine, melatonin, oral pentoxifylline, topical SAMITAL or rhIL-11, oral SsK12, and curcumin may also be utilized but would benefit from validation in larger trials. Besides, Verbascoside, Palifermin, Amifostine, and Avasopasem manganese can be suggested for OM management, while the side effects should be monitored. The accessibility and cost/effectiveness of specific managing strategies of OM should be considered when selecting appropriate options.

Exploring the Influence of Oral and Gut Microbiota on Ulcerative Mucositis: A Pilot Cohort Study

AIM

Comparing oral and gut microbiome profiles between patients with and without ulcerative mucositis during allogeneic stem cell transplantation (aSCT).

MATERIALS AND METHODS

Specimens from oral mucosa, saliva, and stool were collected pre-(T0) and post- (T0 +28d ± 14d) aSCT (T1). Microbiome structure differences were analyzed by 16S-rRNA-gene sequencing, and associations to patients' clinical characteristics were investigated.

RESULTS

Ten of 25 included patients developed ulcerations. The α-diversity decreased between T0 and T1, independent of ulcerations. PERMANOVA revealed differences in beta diversity between T1 stool samples from patients with and without ulcerations. At T1, saliva samples of patients with ulcerations showed an increase of Mycoplasma salvarius, while commensals decreased in saliva and mucosal swabs. The gut microbiome of both groups showed an overabundance of Enterococcus spp., associated with inflammatory conditions. Salival α-diversity of older and overweight patients decreased slower, whereas in mucosal swabs mucositis or impaired renal function was associated with a higher decline. Female gender and history of periodontitis were associated with increased stool microbiome changes, while self-reported probiotics intake was related to reduced changes.

CONCLUSIONS

Ulcerations appeared in 40% of the patients. Distinct microbial changes, including increased abundance of Mycoplasma salivarius in saliva and decreased abundance of commensals, marked those with ulcerations.

TRIAL REGISTRATION

The study was registered in the German Register for Clinical Studies (DRKS00032882).

Microbiome and Communication Disorders: A Tutorial for Clinicians

PURPOSE

Emerging research in the field of microbiology has indicated that host-microbiota interactions play a significant role in regulating health and disease. Whereas the gut microbiome has received the most attention, distinct microbiota in other organs (mouth, larynx, and trachea) may undergo microbial shifts that impact disease states. A comprehensive understanding of microbial mechanisms and their role in communication and swallowing deficits may have downstream diagnostic and therapeutic implications.

METHOD

A literature review was completed to provide a broad overview of the microbiome, including differentiation of commensal versus pathogenic bacteria; cellular mechanisms by which bacteria interact with human cells; site-specific microbial compositional shifts in certain organs; and available reports of oral, laryngeal, and tracheal microbial dysbiosis in conditions that are associated with communication and swallowing deficits.

RESULTS/CONCLUSIONS

This review article is a valuable tutorial for clinicians, specifically introducing them to the concept of dysbiosis, with potential contributions to communication and swallowing deficits. Future research should delineate the role of specific pathogenic bacteria in disease pathogenesis to identify therapeutic targets.

Effect of Dendrobium Officinale on Radioactive Oral Mucositis of Nasopharyngeal Carcinoma and Changes of Oral Microecology

OBJECTIVE

To observe the clinical efficacy of Dendrobium officinale in the treatment of radiotherapy-induced oral mucositis in nasopharyngeal carcinoma patients, and to explore its regulating effect on immune function and oral microbiota by comparing immune-related factors and oral microbiota before and after the intervention.

METHODS

We conducted a randomized double-blinded controlled trial in Zhejiang Cancer Hospital. Sixty patients with nasopharyngeal cancer combined with radiotherapy-induced oral mucositis were randomly divided into a study group and control group, with 30 cases in each group The study group used compound vitamin B12 solution and Dendrobium tea drink, and the control group simply used compound vitamin B12 solution rinse. When the patients developed radiotherapy-induced oral mucositis (at the time of 10F radiotherapy), and after 1 month of Dendrobium treatment (at the end of radiotherapy), the salivary flow rate was measured without stimulation to evaluate the degree of oral mucositis and the clinical efficacy. We also detected the content of EGF in saliva and the content of IL-10 and IL-11 in serum, and analyzed the differences in microbial community structure. All patients consented before enrollment.

RESULTS

The salivary flow rate and oral mucosal fraction of the study group after treatment were significantly improved, which was better than that of the control group(P < .05). The content of IL-10 in the study group after treatment increased significantly compared with that before treatment(P < .05). There was a significant difference between the oral flora of the study group before and after treatment (Unique OTU counts: 5390 vs 3906), and there was also a difference between the oral flora of the study group and control group after treatment (Unique OTU counts: 5671 vs 5439). After treatment, Erysipelotrichales (Phylum Firmicutes, LDA score = 2.80, P = .034), Leptotrichiaceae (Fusobacteria,LDA score = 3.38, P = .030) and Campylobacteraceae (Proteobacteria, LDA score = 3.35, P = .026) were significantly enriched in the study group. The use of Dendrobium officinale in nasopharyngeal carcinoma patients with radiotherapy-induced oral mucositis showed little difference in microbial diversity and abundance, but there were significant differences among oral bacteria genera.

CONCLUSIONS

Dendrobium officinale is effective in the treatment of radiotherapy-induced oral mucositis, which may be related to the improvement of salivary gland function and regulation of the oral microenvironment. Dendrobium officinale may reduce the symptoms of radiotherapy-induced oral mucositis by affecting the systemic cellular immune function. It may reduce the secretion of pro-inflammatory factors of the relevant flora by directly changing the oral flora and regulating the oral micro-ecology.

Metagenomic Profiling of Oral Microbiome Dynamics During Chemoradiotherapy in Head and Neck Squamous Cell Carcinoma Patients

BACKGROUND

We explored the interaction between the oral microbiome and the development of radiation-induced mucositis in patients with head and neck squamous cell cancer (HNSCC) undergoing chemoradiotherapy (CRT). We prospectively studied the oral microbiome and compared it to healthy controls. Additionally, we compared patients with low-grade (LGM) vs. high-grade mucositis (HGM).

METHODS

Ten HNSCC patients scheduled for CRT were included. Saliva samples were characterized prior to, during, and nine months after CRT using metagenomic sequencing. We similarly characterized samples from seven healthy controls. We assessed alpha and beta diversity and examined abundances at different taxonomic levels between (sub)groups.

RESULTS

Patients exhibited significantly reduced alpha diversity compared to controls at all times (p ⟨ 0.05). Differential abundance of taxa between patients and controls was observed at baseline. In patients, the relative abundance of Staphylococcus aureus and Escherichia coli increased significantly during CRT. Capnocytophaga spp. was associated with the definitive CRT patients' subgroup. At baseline, two fungal families (Melampsoraceae and Herpotrichiellaceaea) were more abundant in patients who later developed HGM. No differentially abundant taxa were found between LGM vs. HGM during irradiation.

CONCLUSION

Our findings support the hypothesis that CRT, as well as HNSCC itself, influences the composition of the oral microbiome. Microbial markers found in patients who later developed HGM should be evaluated using independent cohorts to qualify their specific biomarker potential.

Benefit of Avasopasem Manganese on Severe Oral Mucositis in Head and Neck Cancer in the ROMAN Trial: Unplanned Secondary Analysis

Purpose

Oral mucositis (OM) is a debilitating side effect of cisplatin and intensity-modulated radiation therapy (IMRT) in patients with head and neck cancer. The phase 3 ROMAN trial showed avasopasem manganese (AVA) significantly decreased individual endpoints of incidence and duration of severe oral mucositis (SOM, World Health Organization [WHO] grade 3-4), with nominal decrease in severity (WHO grade 4) and significant increase in the delay in onset of SOM. We sought to determine the Net Treatment Benefit (NTB) of AVA versus placebo (PBO) using the generalized pairwise comparisons (GPC) method.

Methods and Materials

GPC is a statistical method that permits simultaneous analysis of several prioritized outcomes, comparing all possible pairs of a patient in the active (ie, AVA) group and a patient from the control (ie, PBO) group. NTB is the net benefit across all the outcomes for AVA compared to PBO. Key clinically relevant outcomes from ROMAN were prioritized: (1) WHO grade 4 OM incidence; (2) SOM incidence; (3) days of SOM; (4) days to SOM onset, with 7 days difference defined as the clinical relevance threshold for SOM days and SOM onset.

Results

GPC analysis of 407 patients (AVA = 241, placebo = 166) stratified by cisplatin schedule and treatment setting resulted in 13,969 pairwise comparisons. AVA showed statistically significant net benefit on all 4 key outcomes with a 53.9% probability that AVA would benefit patients versus a 35.0% probability that PBO would; the difference between these probabilities was a NTB of 18.9% (P = .0012), translating to an AVA number needed to treat of 5.3 patients. All outcomes contributed to NTB, reflecting improvements in SOM incidence, onset and duration, and in grade 4 OM incidence seen in the original ROMAN analysis.

Conclusions

This GPC analysis shows compelling evidence from the ROMAN trial of AVA's clinical benefit across key parameters of SOM burden.

Intravenous immunoglobulin ameliorates doxorubicin-induced intestinal mucositis by inhibiting the Syk/PI3K/Akt axis and ferroptosis

BACKGROUND

Chemotherapy-induced mucositis (CIM) significantly impacts quality of life and reduces survival in patients treated with specific chemotherapeutic agents. However, effective clinical treatments for CIM remain limited. Intravenous immunoglobulin (IVIg), a therapeutic derived from pooled human plasma, is widely used to treat inflammatory diseases. This study aimed to evaluate the therapeutic efficacy and underlying mechanisms of IVIg in CIM.

METHODS

A murine model of doxorubicin (Dox)-induced intestinal mucositis and an organoid model of small intestinal injury were used to explore the protective effects of IVIg on CIM. Immunostaining, transmission electron microscopy (TEM), western blotting (WB), and proteomic analysis were used to further investigate ferroptosis in intestinal epithelial cells and the underlying mechanisms.

RESULTS

In the murine model of Dox-induced intestinal mucositis, intestinal epithelial barrier was destroyed and ferroptosis increased, characterized by weight loss, hematological injury, inflammation, mitochondrial atrophy in intestinal epithelial cells, lipid peroxidation, impairment of tight junctions, and damage to intestinal microvilli. IVIg treatment significantly ameliorated intestinal epithelial barrier damage and reduced ferroptosis both in vitro and in vivo. Proteomic analysis revealed that the FcγR-mediated phagocytosis signaling pathway was involved in the therapeutic effects of IVIg on CIM mice. WB results demonstrated that key proteins downstream of this pathway, Syk, PI3K, and Akt, showed increased phosphorylation in CIM mice, whereas IVIg treatment significantly reduced the phosphorylation levels. Furthermore, the inhibitory effects of IVIg on Dox-induced activation of the Syk/PI3K/Akt axis and ferroptosis, as well as its protective effects on intestinal inflammation and intestinal barrier damage, were reversed by 740Y-P (an PI3K activator) or SC79 (an Akt activator).

CONCLUSIONS

Our findings highlight that IVIg ameliorates CIM by inhibiting ferroptosis via the Syk/PI3K/Akt axis. These results suggest that IVIg may represent a potential therapeutic approach for CIM.

Protective Effects of Cereal-Based Fermented Beverages Against 5-Fluorouracil-Induced Intestinal Damage in Mice

BACKGROUND

5-Fluorouracil (5-FU) is a common chemotherapeutic medication used to treat cancer. However, the intestinal tract may sustain oxidative damage as a result.

OBJECTIVES

The purpose of this study was to clarify the underlying molecular mechanisms and examine the preventive benefits of cereal-based fermented drinks (CFBs) against intestinal injury in mice caused by 5-FU.

METHODS

The mice were injected intraperitoneally with 5-FU to induce intestinal mucosal and treated with CFB. The factors for intestinal barrier integrity, oxidative stress and inflammation were measured.

RESULTS

The findings demonstrated that CFBs had high levels of polyphenol, flavonoids, and peptides and had in vitro high free radical scavenging capacity. Furthermore, CFBs effectively ameliorated 5-FU-induced intestinal epithelium damage, characterized by increasing intestinal tight junctions and reducing apoptosis in intestinal cells. These protective effects may attribute to the increased activity of antioxidant-related enzymes (SOD, CAT, and GSH) as well as decreased amounts of inflammatory and oxidative damage markers (IL-1β, TNF-α, and MDA) in the intestinal tract.

CONCLUSIONS

Overall, these results show that CFBs can mitigate intestinal damage caused by 5-FU by reducing oxidative stress, suggesting the potential utility of CFBs for therapeutic treatment against intestinal mucositis.

Accidental methotrexate overdose leading to multisystem toxicity: A case report

Background

Methotrexate (MTX) is an extensively used chemotherapeutic agent with well-characterized toxicity profiles. This case report describes the clinical presentation, management, and outcome of a patient presenting with severe MTX toxicity.

Case Presentation

A 35-year-old Bangladeshi female was admitted on March 9, 2024, with severe mucosal ulcerations, painful skin lesions, and gastrointestinal bleeding after ingesting Methotrexate daily for 12 days by mistake instead of the medication prescribed to her. On physical examination, there was severe injury involving skin and mucosa. The laboratory results showed severe pancytopenia and liver and kidney function in derangement. There was gradual improvement with the prompt withdrawal of Methotrexate, Folinic Acid therapy, and supportive therapies; most of the laboratory values returned to normal by day 14.

Conclusion

This case was one of severe Methotrexate poisoning, leading to profound systemic toxicity. Thus, timely recognition, immediate drug withdrawal, and aggressive supportive care comprising Folinic Acid therapy and hydration played a major role in this patient's management.

Xiao-Ban-Xia Decoction Alleviates Chemotherapy-Induced Nausea and Vomiting by Inhibiting Ferroptosis via Activation of The Nrf2/SLC7A11/GPX4 Pathway

Chemotherapy-induced nausea and vomiting (CINV) represents the common gastrointestinal side effect for cancer patients. Xiao-Ban-Xia decoction (XBXD), a classical anti-emetic traditional Chinese medicine formula, is frequently used for the clinical treatment of CINV. This study used a cisplatin-induced rat pica model to explore whether the anti-emetic mechanism of XBXD in treating CINV is related to ferroptosis. The inflammatory damage of the gastrointestinal tract is evaluated by HE staining and ELISA. The degree of ferroptosis are validated by the iron deposition, the levels of ROS, MDA, and GSH, and the ultrastructure of mitochondria in the gastric antrum and ileum. The potential ferroptosis-related targets of XBXD against CINV are screened by network pharmacology and further assessed by Western blot. XBXD significantly decreased the kaolin consumption in rats, and improved the inflammatory pathological damage, with decreased levels of HMGB1, IL-1β, and TNF-α. Furthermore, XBXD significantly suppressed ferroptosis, as indicated by the improvement of iron deposition, mitochondrial abnormalities, and oxidative stress. The network pharmacology and Western blot results indicated that XBXD activated the Nrf2/SLC7A11/GPX4 signaling pathway. This study proved that XBXD activates the Nrf2/SLC7A11/GPX4 signaling pathway, thereby inhibiting ferroptosis, which represents a critical anti-emetic mechanism of XBXD in combatting CINV.

"It's like being chained up": the oral mucositis experiences of children and young people with cancer, their parents, and healthcare professionals- a qualitative study

OBJECTIVE

The objective is to explore the experiences of children and young people (CYP) with cancer, their parents, and healthcare professionals (HCPs) involved in their care of oral mucositis.

DESIGN

A qualitative study was conducted. CYP with experience of mucositis were purposively sampled, aiming for diversity in age, sex and cancer diagnosis. HCPs were purposively sampled aiming for diversity in professional role and years of experience. Semi-structured interviews with CYP and their parents and focus groups with HCPs were conducted. Interviews were audio recorded and professionally transcribed. Anonymised transcripts underwent reflexive thematic analysis using an inductive essentialist approach. Codes were discussed and constant comparisons made to increase validity. Recruitment occurred alongside analysis until no new codes were identified.

RESULTS

27 participants were interviewed (8 CYP, 10 parents, 9 HCPs). CYP had diverse cancer diagnoses and were aged between 8 and 15 years. HCPs had diverse professional roles across medicine, dentistry, nursing, dental nursing, and play therapy with a mean of 7.4 years of experience in their individual role. Four themes were generated: (1) mucositis as a multifaceted, negative emotive experience, (2) being taken away from 'normality', (3) complex biopsychosocial impact on eating and (4) management of mucositis presents additional strain. Within these themes, multiple subthemes were generated and cross-cutting challenges in maintaining oral health were identified.

CONCLUSION

Oral mucositis presents a significant challenge to CYP, families and HCPs during cancer treatment functionally, psychologically and socially, with an adverse impact on treatment experiences. Prevention of oral mucositis is a priority to these groups within supportive cancer care.

Postbiotic Effect of Escherichia coli CEC15 and Escherichia coli Nissle 1917 on a Murine Model of 5-FU-induced Intestinal Mucositis

Probiotics are live microorganisms that, when administered in adequate amounts, can bring health benefits to the host. Most of these organisms are found naturally in the human gastrointestinal tract. Escherichia coli strains Nissle 1917 (EcN), and CEC15 have shown beneficial effects in murine models of intestinal inflammation, such as colitis and mucositis. The present study evaluated the effects as postbiotic of heat-inactivated and cell-free supernatant preparations of EcN and CEC15 in attenuating 5-fluorouracil (5-FU)-induced intestinal mucositis in mice and compared them with the probiotic effects of the live preparations. BALB/c mice were fed, by daily gavage, with 1010 CFU of live or inactivated bacteria or with 300 µL of cell-free supernatant for 12 days. On the 10th day, all animals, except for the control group, received an intraperitoneal injection of 5-FU (300 mg/kg). After 72 h of 5-FU administration, animals were euthanized, and the ileum and blood were collected for analysis. Treatments with live and heat-inactivated CEC15 mitigated weight loss, preserved intestinal length, reduced histological damage, maintained goblet cells, decreased neutrophil infiltration, and modulated expression of inflammatory and barrier genes when compared to 5-FU mucositis controls. EcN showed more limited effects. CEC15 upregulated mRNA expression of the mucin MUC2 and tight junction protein TJP1. CEC15 demonstrated protective effects against 5-FU-induced mucositis, whether administered with live, heat-inactivated, or cell-free supernatant. This suggests that CEC15 mediates a protective response via secreted metabolites and does not require viability. The postbiotic forms of CEC15 present advantages for use in immunocompromised patients. This study elucidates the anti-inflammatory and barrier-protective effects of CEC15 against intestinal mucositis.

Oral microbial changes, oral mucositis and febrile neutropenia during myelosuppressive chemotherapy in patients diagnosed with a solid tumor or lymphoma

Objectives

To evaluate the possible changes of the oral microbiome during myelosuppressive chemotherapy (CT) and to investigate the potential relationship between the oral microbiome, the presence of oral mucositis (OM) and febrile neutropenia (FN).

Methods

A prospective, longitudinal, observational study was conducted in patients receiving myelosuppressive CT for a solid tumor or lymphoma. Oral rinsing samples were retrieved before, during and after the start of CT, but also when OM or FN was present. The samples were analyzed using 16S rRNA gene amplicon sequencing and statistical analysis was performed using alpha (Shannon) and beta (PERMANOVA) diversity analyses. Furthermore, differential abundances were analyzed using ALDEx2v1.32.0. Differences between groups were calculated using the Mann Whitney U-test, Kruskal-Wallis test and Wilcoxon Signed Rank using R.

Results

Forty-six patients, with a mean follow up of 114 days, were included for analysis and a total of 138 oral rinsing samples were available in the CLR-transformed data for PERMANOVA and 137 samples-for alpha diversity calculation. Significant changes in alpha diversity were seen when OM or FN was present. Moreover, significant changes were seen in beta diversity during the course of the CT treatment and when OM was present. Genera showing substantial changes in relative abundance were Streptococcus during the course of CT treatment and Prevotella, Fusobacterium, Selenomonas, Actinomyces and Leptotrichia when OM was present.

Conclusion

Changes in the oral microbiome were observed during the CT-regimen and when OM was present. Furthermore, changes of the oral microbiota during FN episodes were observed; however, larger studies should be performed to substantiate our results.

Screening of biomarkers in acute radiation enteritis based on microbiome and clustering methods

BACKGROUND

Radiation enteritis (RE) is a common complication of radiotherapy for abdominal and pelvic tumors, adversely affecting treatment outcomes and patients' quality of life. Gut microbiome alterations may contribute to RE development, but the underlying pathogenic factors are not fully understood. This study aimed to characterize the intestinal microbial changes associated with RE and severe acute radiation enteritis (SARE) and to identify predictive biomarkers.

METHODS

We enrolled 50 cervical cancer patients undergoing radiotherapy and 15 healthy women (controls). Stool samples were collected at the baseline and during weeks 2, 4, and 6 of radiotherapy, and then analyzed using 16 S rDNA sequencing and bioinformatics.

RESULTS

Although the Bacteroidetes/Firmicutes (B/F) ratio was higher in patients with RE or SARE, it alone could not predict these conditions. Three enterotypes were identified based on dominant genera: Blautia (enterotype 1), Escherichia-Shigella (enterotype 2), and Faecalibacterium (enterotype 3). A decrease in Blautia and an increase in Escherichia-Shigella and Faecalibacterium were correlated with RE and SARE. Univariate logistic regression revealed that the Faecalibacterium enterotype at the baseline was associated with a 4.4-fold higher risk of developing SARE (odds ratio 5.400; P = 0.017). The Escherichia-Shigella enterotype was also linked to increased SARE incidence.

CONCLUSION

These findings suggest that while single bacterial genera or the B/F ratio are insufficient predictors, enterotype classification may serve as a potential biomarker for predicting SARE in patients undergoing radiotherapy.

Mitigation of chemotherapy-induced experimental intestinal mucositis through postbiotic lactate

Postbiotic lactate modulates the immune system in inflammatory bowel diseases. However, its role in experimental intestinal mucositis (IM) has not been elucidated. This study aimed to evaluate the effects of lactate supplementation (1 and 2 × 10-1 mol/l) in a 5-fluorouracil (5-FU)-induced IM model. Male BALB/c mice (6-8 weeks old) were randomly divided into four groups: control (CTL), mucositis (MUC), mucositis with 1 × 10-1 mol/l lactate solution (MUC10), and mucositis with 2 × 10-1 mol/l lactate solution (MUC200). Lactate was administered via oral gavage for 10 days. Following the treatment period, the animals were subjected to an intraperitoneal injection of 300 mg/kg 5-FU to induce IM and were euthanized 72 h later for analysis. The MUC group presented intestinal damage with a poor histological score and decreased morphometric parameters as well as decreased mucus production and increased inflammatory infiltration and intestinal permeability compared to those of the CTL group (P < .05). However, the MUC200 group exhibited better results for the evaluated parameters than the MUC group (P < .05). Notably, the results in the MUC10 group were similar to those in the MUC group (P > .05). In conclusion, lactate supplementation attenuates mucositis-induced damage in a dose-dependent manner.

Intralesional corticosteroid therapy for non-healing persistent radiation-induced oropharyngeal mucositis

PURPOSE

Oropharyngeal mucositis is a common complication of anticancer therapy. This study aimed to determine the effectiveness and safety of intralesional corticosteroid therapy (ICT) in the management of persistent mucositis.

METHODS

A retrospective chart review of patients who underwent ICT in the oral cavity to manage oral mucositis managed with basic oral care and preventive modalities and persisting at least 6 weeks after head and neck radiation or chemoradiation therapy completion between November 2017 and September 2023 was performed. Bio-demographic data, cancer and anticancer therapy characteristics, medical history, and mucositis-related variables were extracted from electronic medical records.

RESULTS

Among the 34 participants, 22 (64.7%) were male. Twenty (58.8%) participants received radiotherapy; the rest received chemoradiation therapy. Before the ICT, the median mucositis lesion surface area was 225 mm2 (range 9-2025 mm2), and 22 (64.7%) patients had grade III mucositis. Post-intervention, the median size was reduced to 0 mm2 (range 0-1600 mm2). Clinically effective response (≥ 75% size and symptom reduction) was observed in 28 (82.4%) participants over a median of 26 days (7-60 days). Within this cohort, complete healing of the lesion was seen in 18 (64.3%) subjects. Overall, 25 (73.5%) participants experienced a downgradation in the mucositis stage. Local complications from injections were found in two (5.7%) participants. A correlation was found between clinically effective relief and absence of trismus (p = .03) and smaller pre-procedure surface area (p = .009).

CONCLUSION

The ICT represents a viable option in managing non-healing, persistent radiation, and chemoradiation-induced oral mucositis. The modality was well tolerated and had no systemic complications.

Molecular mechanisms underlying methotrexate-induced intestinal injury and protective strategies

Methotrexate (MTX) is a folic acid reductase inhibitor that manages various malignancies as well as immune-mediated inflammatory chronic diseases. Despite being frequently prescribed, MTX's severe multiple toxicities can occasionally limit its therapeutic potential. Intestinal toxicity is a severe adverse effect associated with the administration of MTX, and patients are significantly burdened by MTX-provoked intestinal mucositis. However, the mechanism of such intestinal toxicity is not entirely understood, mechanistic studies demonstrated oxidative stress and inflammatory reactions as key factors that lead to the development of MTX-induced intestinal injury. Besides, MTX causes intestinal cells to express pro-inflammatory cytokines like interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), which activate nuclear factor-kappa B (NF-κB). This is followed by the activation of the Janus kinase/signal transducer and activator of the transcription3 (JAK/STAT3) signaling pathway. Moreover, because of its dual anti-inflammatory and antioxidative properties, nuclear factor erythroid-2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) has been considered a critical signaling pathway that counteracts oxidative stress in MTX-induced intestinal injury. Several agents have potential protective effects in counteracting MTX-provoked intestinal injury such as omega-3 polyunsaturated fatty acids, taurine, umbelliferone, vinpocetine, perindopril, rutin, hesperidin, lycopene, quercetin, apocynin, lactobacillus, berberine, zinc, and nifuroxazide. This review aims to summarize the potential redox molecular mechanisms of MTX-induced intestinal injury and how they can be alleviated. In conclusion, studying these molecular pathways might open the way for early alleviation of the intestinal damage and the development of various agent plans to attenuate MTX-mediated intestinal injury.

Elevated risk of adverse effects from foodborne contaminants and drugs in inflammatory bowel disease: a review

The global burden of Inflammatory bowel disease (IBD) has been rising over the last decades. IBD is an intestinal disorder with a complex and largely unknown etiology. The disease is characterized by a chronically inflamed gastrointestinal tract, with intermittent phases of exacerbation and remission. This compromised intestinal barrier can contribute to, enhance, or even enable the toxicity of drugs, food-borne chemicals and particulate matter. This review discusses whether the rising prevalence of IBD in our society warrants the consideration of IBD patients as a specific population group in toxicological safety assessment. Various in vivo, ex vivo and in vitro models are discussed that can simulate hallmarks of IBD and may be used to study the effects of prevalent intestinal inflammation on the hazards of these various toxicants. In conclusion, risk assessments based on healthy individuals may not sufficiently cover IBD patient safety and it is suggested to consider this susceptible subgroup of the population in future toxicological assessments.

Caspofungin formulations for buccal and sublingual mucosae anti-fungal infections: physicochemical characterization, rheological analysis, release and ex vivo permeability profiles

AIM

Oral candidiasis is often challenging due to limited effectiveness of topical treatments. This study aimed to develop novel caspofungin formulations for administration onto the oral mucosa to enhance drug retention and efficacy.

METHOD

Five caspofungin (2%, w/v) formulations were developed to assess their permeability, retention and mucoadhesiveness. Ex vivo permeability assays were performed on buccal and sublingual mucosae, and histological analyses conducted to evaluate tissue tolerance.

RESULTS

Formulation composed of chitosan demonstrated the highest retention in both buccal (5183.24 ± 587.32 µg/cm2) and sublingual (1090.72 ± 110.26 µg/cm2) mucosae. Other formulations exhibited significantly lower retention, ranging from 7.53 ± 0.81 to 1852.10 ± 193.24 µg/cm2 in buccal mucosa and 1.64 ± 0.14 to 317.74 ± 31.78 µg/cm2 in sublingual mucosa. Chitosan-based formulation exhibited the highest mucoadhesive strength, with values of 5179.05 ± 31.99 mN/cm2 for buccal and 7026.10 ± 123.41 mN/cm2 for sublingual mucosae, and also superior extensibility, which facilitates application in the oral cavity. All formulations showed antifungal activity against Candida spp., and histological analyses revealed minor epithelial alterations.

CONCLUSION

The developed formulations offer distinct advantages for treating oral candidiasis, with chitosan formulation emerging as the most promising due to its superior retention, mucoadhesion force, and spreadability, making it a potential candidate for further clinical investigation.

Photobiomodulation for the prevention and treatment of oral mucositis in patients submitted to hematopoietic stem cell transplantation: health quality evaluation

OBJECTIVE

To evaluate the quality of oral health care through indicators in patients undergoing hematopoietic stem cell transplantation for the management of oral mucositis.

METHODS

Thirty-five patients were evaluated. Photobiomodulation was performed during the conditioning regimen, 1 day, 5 days, and 10 days after transplantation. Four process indicators and 13 outcome indicators were used to evaluate the effectiveness of the intervention, according to SQUIRE 2.0.

RESULTS

All process indicators demonstrated a compliance rate of 100% to the desired standard. Outcome indicators revealed that 66.6% of patients experienced mucositis during at least one follow-up period. A statistically significant increase was observed between periods of 1 and 5 days post-transplant, as well as between 1 and 10 days post-transplant (p < 0.05), with a predominance of grade I mucositis (p = 0.014). Four patients (16.7%) reported feeling pain, occurring between 5 and 10 days after transplantation, with moderate pain being the most prevalent. Oral mucositis did not show a statistically significant association with pain, associated treatments, leukopenia, comorbidities, or type of transplant.

CONCLUSIONS

The indicators demonstrated their suitability for evaluating oral health in both the prevention and treatment of oral mucositis in these patients. Furthermore, the effectiveness of photobiomodulation in improving the quality of oral health in the patients studied was confirmed.

Cold Atmospheric Pressure Plasma May Prevent Oral Mucositis-Related Candidemia in Chemotherapy-Treated Rats

Oral mucositis associated with candidiasis can causes systemic candidemia, posing a risk to cancer patients administered antineoplastic therapy. Cold atmospheric pressure plasma jets (CAPPJs) have antifungal and anti-inflammatory properties. This study evaluated the effects CAPPJs in preventing systemic fungal dissemination in a murine model of oral mucositis associated with candidiasis. Forty Wistar rats were divided into groups: CAPPJs (treated) and non-treated controls (for comparison), with subgroups subject to 24 and 72 h of treatment (n = 10 each). Four cycles of chemotherapy (cisplatin and 5-fluorouracil (5-FU)) were administered, followed by oral inoculation of Candida albicans for 3 days. Mucosal damage was induced on the lateral side of tongue with 50% acetic acid. CAPPJ treatment was performed on the lesion for 5 min (2 days). Body weight was assessed daily. Fungal dissemination was conducted using organ macerates and plated on Sabouraud Agar with chloramphenicol. Blood samples were obtained for blood count tests. Chemotherapy affected the general health of the animals, as evidenced by body weight loss. Treatment with CAPPJs showed an inhibitory effect on C. albicans, with a significant reduction in fungal recovery from the tongue after 24 h (p < 0.05). Interestingly, systemic fungal dissemination was significantly reduced after 24 and 72 h of treatment when compared to control (p < 0.05). Taken together, these results suggest that CAPPJs have potential for clinical application in patients with oral mucositis at risk of candidemia.

Painful Realities: Navigating the Complexities of Head and Neck Cancer Pain

BACKGROUND

Head and neck cancer (HNC) and its treatments can cause significant pain, which can profoundly impact patients' quality of life and treatment outcomes. Understanding the full scope of HNC pain is essential for effective management and improved patient care.

OBJECTIVE

This review aims to comprehensively analyze the multifaceted nature of pain experienced by individuals with HNC, including its various etiologies and management strategies.

RESULTS

HNC pain can arise from tumor extent, treatment-related toxicity, or comorbid conditions. The pathophysiology involves complex interactions between nociceptive, neuropathic, and inflammatory mechanisms. Optimal pain control requires a multimodal patient-tailored approach utilizing both pharmacological and non-pharmacological therapies.

CONCLUSION

Enhancing our understanding of HNC pain and optimizing its management is imperative for improving the overall well-being and treatment outcomes of affected individuals. Future research should focus on understanding detailed pain mechanisms, with the goal of developing personalized pain management strategies and exploring novel therapeutic targets. By implementing comprehensive approaches to HNC pain management, healthcare providers can better support patients through their cancer treatment journey.

MicroRNA hsa-let-7e-5p in hUC-MSC-EVs alleviates oral mucositis by targeting TAB2

Oral mucositis (OM) is a severe side effect of anti-cancer therapy, with limited available treatments. Mesenchymal stem cells (MSCs) and their secreted extracellular vesicles (EVs) have demonstrated effective protection against OM. However, the underlying mechanism remains elusive. In the current study, we purified EVs secreted by human umbilical cord MSCs (hUC-MSC-EVs) and investigated their role in lipopolysaccharide (LPS)-induced human oral keratinocytes (HOKs). We observed that treatment with hUC-MSC-EVs significantly reduced the inflammatory response of HOKs to LPS induction. Through small RNA-seq using miRNAs extracted from hUC-MSC-EVs, we identified hsa-let-7e-5p as one of the most highly expressed miRNAs. Bioinformatic analysis data indicated that hsa-let-7e-5p may inhibit the NF-κB signalling pathway by targeting TAB2. Overexpression of the hsa-let-7e-5p inhibitor significantly attenuated the anti-inflammatory effect of hUC-MSC-EVs in LPS-induced HOKs, which could be reversed by the knockdown of TAB2. In addition, we administered hUC-MSC-EVs in a hamster model for OM and observed that these EVs alleviated OM phenotypes. Taken together, our observations suggest that hsa-let-7e-5p in hUC-MSC-EVs could protect the oral mucosa from OM by repressing TAB2 expression.

Kinetics of neutrophil extracellular traps and cytokines in oral mucositis and Candida infection

OBJECTIVE

This study investigated the concentrations of neutrophil extracellular traps (NET) and salivary cytokines (IL-1β, IL-6, IL-8/CXCL8, TNF, and TGF-β1) in patients undergoing chemotherapy and their associations with oral mucositis (OM) and Candida infection.

MATERIALS AND METHODS

This prospective longitudinal study performed at a Brazilian service included 60 adults diagnosed with hematolymphoid diseases. Saliva samples were collected on days D0, D3, D10, and D15. Cytokines were analyzed by ELISA and NET formation by identification of the myeloperoxidase-DNA complex. Oral Candida spp. was cultured.

RESULTS

OM occurred in 43.3% of patients and oral candidiasis in 20%. However, 66% of individuals had positive cultures for C. albicans. Higher concentrations of IL-6, IL-8/CXCL8, and TNF and lower concentrations of TGF-β1 were observed in patients with OM. C. albicans infection contributed to the increase in IL-8/CXCL8, TGF-β1, and TNF. Individuals with OM or with oral candidiasis had significant reductions in NET formation. In contrast, individuals with C. albicans and with concomitant C. albicans and OM exhibited higher NET formation.

CONCLUSION

The kinetics of cytokine levels and NET formation in chemotherapy-induced OM appears to be altered by Candida infection, even in the absence of clinical signs of oral candidiasis.

Unlocking the Potential of Probiotics: A Comprehensive Review on Research, Production, and Regulation of Probiotics

This review provides a comprehensive overview of the current state of probiotic research, covering a wide range of topics, including strain identification, functional characterization, preclinical and clinical evaluations, mechanisms of action, therapeutic applications, manufacturing considerations, and future directions. The screening process for potential probiotics involves phenotypic and genomic analysis to identify strains with health-promoting properties while excluding those with any factor that could be harmful to the host. In vitro assays for evaluating probiotic traits such as acid tolerance, bile metabolism, adhesion properties, and antimicrobial effects are described. The review highlights promising findings from in vivo studies on probiotic mitigation of inflammatory bowel diseases, chemotherapy-induced mucositis, dysbiosis, obesity, diabetes, and bone health, primarily through immunomodulation and modulation of the local microbiota in human and animal models. Clinical studies demonstrating beneficial modulation of metabolic diseases and human central nervous system function are also presented. Manufacturing processes significantly impact the growth, viability, and properties of probiotics, and the composition of the product matrix and supplementation with prebiotics or other strains can modify their effects. The lack of regulatory oversight raises concerns about the quality, safety, and labeling accuracy of commercial probiotics, particularly for vulnerable populations. Advancements in multi-omics approaches, especially probiogenomics, will provide a deeper understanding of the mechanisms behind probiotic functionality, allowing for personalized and targeted probiotic therapies. However, it is crucial to simultaneously focus on improving manufacturing practices, implementing quality control standards, and establishing regulatory oversight to ensure the safety and efficacy of probiotic products in the face of increasing therapeutic applications.

RIP3 regulates doxorubicin-induced intestinal mucositis via FUT2-mediated α-1,2-fucosylation

OBJECTIVE

Intestinal mucositis is one of the common side effects of anti-cancer chemotherapy. However, the molecular mechanisms involved in mucositis development remain incompletely understood. In this study, we investigated the function of receptor-interacting protein kinase 3 (RIP3/RIPK3) in regulating doxorubicin-induced intestinal mucositis and its potential mechanisms.

METHODS

Intestinal mucositis animal models were induced in mice for in vivo studies. Rat intestinal cell line IEC-6 was used for in vitro studies. RNA‑seq was used to explore the transcriptomic changes in doxorubicin-induced intestinal mucositis. Intact glycopeptide characterization using mass spectrometry was applied to identify α-1,2-fucosylated proteins associated with mucositis.

RESULTS

Doxorubicin treatment increased RIP3 expression in the intestine and caused severe intestinal mucositis in the mice, depletion of RIP3 abolished doxorubicin-induced intestinal mucositis. RIP3-mediated doxorubicin-induced mucositis did not depend on mixed lineage kinase domain-like (MLKL) but on α-1,2-fucosyltransferase 2 (FUT2)-catalyzed α-1,2-fucosylation on inflammation-related proteins. Deficiency of MLKL did not affect intestinal mucositis, whereas inhibition of α-1,2-fucosylation by 2-deoxy-D-galactose (2dGal) profoundly attenuated doxorubicin-induced inflammation and mucositis.

CONCLUSIONS

RIP3-FUT2 pathway is a central node in doxorubicin-induced intestinal mucositis. Targeting intestinal RIP3 and/or FUT2-mediated α-1,2-fucosylation may provide potential targets for preventing chemotherapy-induced intestinal mucositis.

Impact of kV-cone beam computed tomography dose on DNA repair mechanisms: A pilot study

PURPOSE

In head and neck squamous cell carcinoma (HNSCC), early complications of the radiotherapy (RT) are observed from the beginning of the treatment to a few months after its end. During external radiotherapy treatment, several patient-dependent parameters can cause a modification of the dose distribution compared to the planned distribution due to variation in patient positioning, anatomy, or intra-fractional movements for example. To verify these parameters during treatment sessions, one of the most commonly used solutions is the cone-beam computed tomography (CBCT). Nowadays, the use of CBCT may constitutes a significant part of the total dose at the end of treatment (up to 10 cGy per session) and more often the volume irradiated by imaging is larger than the one irradiated by the treatment, leading to unintentional irradiation of nearby organs. In this study, we asked whether the imaging low dose added to a following fraction dose (2Gy) may affect the biological response in terms of DNA repair.

MATERIAL AND METHODS

Using an IVInomad dosimeter and scintillating fiber probes specially designed for this exploratory study, we exposed fibroblasts cells from head and neck cancer (HNC) patients to a CBCT dose followed by a radiotherapy fraction dose. DNA double strand breaks and DNA repair were assessed by immunofluorescence using the biomarkers gamma H2AX (γH2AX) and pATM.

RESULTS

The median dose of CBCT was measured between 17 to 21 mGy per session. The kinetics of both biomarkers were found to be strongly dependent on the individual factor in radiosensitive patients. For HNC patients, a prior CBCT dose applied few minutes before the 2Gy dose may have a sublinear effect on the DNA repair mechanisms and potentially on observed health tissue toxicity.

CONCLUSION

The preliminary results obtained highlight the importance of individual and tissue factors for recognizing and repairing DSB during a treatment by radiotherapy using CBCT.

Thalidomide attenuates radiation-induced apoptosis and pro-inflammatory cytokine secretion in oral epithelial cells by promoting LZTS3 expression

Radiation-induced oral mucositis (RIOM) is a prevalent oral complication that occurs in individuals undergoing radiotherapy or radiation treatment for head and neck tumors. The presence of oral mucosal rupture and ulcerative lesions, which are the defining features of this condition, can significantly affect the quality of life of patients. Additionally, it can interfere with tumor therapy and contribute to an unfavorable prognosis. Current evidence suggests that cellular inflammation and programmed cell death are important factors in disease development. Moreover, thalidomide (THD) has been revealed to reduce the incidence and severity of RIOM in patients undergoing chemoradiotherapy for nasopharyngeal carcinoma. However, the mechanism through which THD improves RIOM remains unknown. This study aimed to investigate the role of LZTS3 in RIOM by analyzing various sequencing datasets and conducting knockdown and overexpression experiments. We used small interfering RNA transfection and LZTS3 overexpression, followed by validation through polymerase chain reaction, western blotting, flow cytometry, and enzyme-linked immunosorbent assay. In this study, we identified LZTS3 as a potential target for THD regulation in RIOM. Through a series of experiments, we confirmed that LZTS3 has the ability to inhibit the inflammatory response and apoptosis of cells. In addition, we also found that THD can regulate the expression of LZTS3 by upregulating, thereby affecting inflammatory response and apoptosis. We repeated these results in a live animal model. In summary, THD has the potential to reduce the occurrence of oral mucositis in patients by upregulating LZTS3 levels. These findings provide a promising avenue for future drug research and development to treat RIOM.

Oral Mucositis in Adult Cancer Patients Undergoing Chemotherapy: Six-Month On-Treatment Follow-Up

Objectives. Oral mucositis (OM) is a common adverse reaction associated with chemotherapy. We conducted a six-month longitudinal study to estimate the cumulative incidence of OM during the first six months of chemotherapy in adult patients with cancer other than head and neck cancer. Secondary objectives were as follows: (a) to scrutinize the oral health status of these patients and its evolution during chemotherapy, as assessed by oral health indices; (b) to estimate adherence to prescribed oral hygiene protocol during chemotherapy; and (c) to analyze ulceration-free survival in these patients. Methods. Sixty-four patients participated. Dental health and oral hygiene were assessed at baseline and at the end. Every month, blood tests were performed and oral lesions were recorded. This study was observational, with the only intervention being instruction in the hygiene protocol. The cumulative incidence of OM was estimated with the patient as the unit of analysis. A repeated measures ANOVA was applied to analyze the monthly blood test results. Ulceration-free survival analysis was conducted with adherence to the oral hygiene protocol as a grouping factor, followed by Cox proportional-hazards regression. Results. The six-month cumulative incidence rate was 43.75%, 95%CI (31.58-56.67%) for OM grade 2 or higher. The hazard ratio of ulceration associated with adherence to the hygiene protocol was 0.154, 95%CI (0.049-0.483), adjusted for age, sex, baseline hygiene index, and class of treatment. Conclusions. Compliance with hygiene recommendations would decrease the OM risk by more than six times, compared to non-compliance.

Oral Care in Head and Neck Radiotherapy: Proposal for an Oral Hygiene Protocol

This review aims to provide a comprehensive overview of the literature on the oral side effects caused by radiotherapy for head and neck cancers. Various treatments are examined to mitigate these sequelae, and a protocol is proposed for dentists and dental hygienists to manage oncological patients. A literature search was conducted to select relevant articles addressing the effects of radiotherapy treatments on the oral cavity, with a particular focus on the development of mucositis, candidiasis, changes in salivary pH, trismus, fibrosis, and alterations in the oral biofilm. PubMed and MedLine were used as search engines, with keyword combinations including: head and neck cancer, mucositis, candida, dental care, dental hygiene, epidemiology, oral microbiome, biofilm, trismus, fibrosis, and salivary pH. A total of 226 articles were identified, spanning the period from 1998 to 2023. Articles deemed inappropriate or in languages other than English or Italian were excluded. A management protocol for oncological patients was proposed, divided into two phases: home-based and professional. Despite the advancements in intensity-modulated radiation therapy, it is impossible to completely avoid damage to healthy tissues. Preventive education and counseling in the dental chair, ongoing motivation, and education about oral hygiene are crucial to combine a good therapeutic outcome with an improved quality of life for the patient.

Probiotics in the management of radiation-induced oral mucositis

Oral mucositis is a common and debilitating oral complication in head and neck cancer patients undergoing radiotherapy, resulting in diminished quality of life and potential treatment disruptions. Oral microbiota has long been recognized as a contributing factor in the initiation and progression of radiation-induced oral mucositis (RIOM). Numerous studies have indicated that the radiation-induced oral microbial dysbiosis promotes the occurrence and severity of oral mucositis. Therefore, approaches that modulate oral microbial ecology are promising for the management of RIOM. Probiotics as a relatively predicable and safe measure that modulates microecology have garnered significant interest. In this review, we discussed the correlation between RIOM and oral microbiota, with a particular focus on the efficacy of probiotics in the control of RIOM, in order to provide novel paradigm for the management of this disease.

Self-perceived oral health in hemato-oncological patients and the relation to quality of life

PURPOSE

To assess the self-reported oral health and oral health-related quality of life of patients diagnosed with hemato-oncological disease.

PATIENTS AND METHODS

Data was collected through a digital questionnaire in collaboration with the Dutch patient organization Hematon. The questionnaires EORTC-QLQ-C30, EORTC-QLQ-OH15, shortened Xerostomia Inventory (XI), and the OHIP-14 were used.

RESULTS

Seven hundred five patients were included (52.5% female, mean age 63.2 ± 10.1). The majority was diagnosed more than 2 years ago (86%) and had received treatment (81%) for their disease. Lymphoma, leukemia, and multiple myeloma were the most frequent malignancies. Chemotherapy alone, chemotherapy in combination with targeted therapy or immunotherapy, and myeloablative chemotherapy followed by autologous stem cell transplantation were the most common treatment modalities. The XI identified that 40.5% met the criteria for xerostomia. Other complaints included mouth soreness and sensitivity, gingival pain and bleeding, problems with teeth or with an ill-fitting denture. Despite reporting oral complaints, most patients experienced a rather good OH-QoL. A high xerostomia score led to a significantly lower OH-QoL. Female gender, history of stem cell transplantation, radiation to head and neck, and multiple daily medication use were significant predictors of xerostomia.

CONCLUSION

Patients with hematologic malignancies frequently reported a dry mouth and other oral complaints including mouth soreness and sensitivity, gingival pain and bleeding, and problems with teeth. Despite these oral complaints, most patients experienced a relatively good OH-QoL. Future longitudinal studies are needed, and health professionals should have an active role in providing oral supportive care based on patients' individual needs.

Primer on fibroblast growth factor 7 (FGF 7)

Fibroblast growth factor 7 (FGF7), also known as keratinocyte growth factor (KGF), is an important member of the FGF family that is mainly expressed by cells of mesenchymal origin while affecting specifically epithelial cells. Thus, FGF7 is widely expressed in diverse tissues, especially in urinary system, gastrointestinal tract (GI-tract), respiratory system, skin, and reproductive system. By interacting specifically with FGFR2-IIIb, FGF7 activates several downstream signal pathways, including Ras, PI3K-Akt, and PLCs. Previous studies of FGF7 mutants also have implicated its roles in various biological processes including development of essential organs and tissue homeostasis in adults. Moreover, more publications have reported that FGF7 and/or FGF7/FGFR2-IIIb-associated signaling pathway are involved in the progression of various heritable or acquired human diseases: heritable conditions like autosomal dominant polycystic kidney disease (ADPKD) and non-syndromic cleft lip and palate (NS CLP), where it promotes cyst formation and affects craniofacial development, respectively; acquired non-malignant diseases such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), mucositis, osteoarticular disorders, and metabolic diseases, where it influences inflammation, repair, and metabolic control; and tumorigenesis and malignant diseases, including benign prostatic hyperplasia (BPH), prostate cancer, gastric cancer, and ovarian cancer, where it enhances cell proliferation, invasion, and chemotherapy resistance. Targeting FGF7 pathways holds therapeutic potential for managing these conditions, underscoring the need for further research to explore its clinical applications. Having more insights into the function and underlying molecular mechanisms of FGF7 is warranted to facilitate the development of effective treatments in the future. Here, we discuss FGF7 genomic structure, signal pathway, expression pattern during embryonic development and in adult organs and mutants along with phenotypes, as well as associated diseases.

Mucositis-associated bloodstream infections in adult haematology patients with fever during neutropenia: risk factors and the impact of mucositis severity

PURPOSE

Haematology patients with high-risk neutropenia are prone to mucosal-barrier injury-associated laboratory-confirmed bloodstream infections (MBI-LCBI). We assessed risk factors for MBI-LCBI including candidaemia in neutropenic haematology patients with fever.

METHODS

This prospective observational study was performed in six dedicated haematology units in the Netherlands. Eligible haematology patients had neutropenia < 500/mL for ≥ 7 days and had fever. MBI-LCBIs were classified according to Centers for Disease Control (CDC) definitions and were followed until the end of neutropenia > 500/mL or discharge.

RESULTS

We included 416 patients from December 2014 until August 2019. We observed 63 MBI-LCBIs. Neither clinical mucositis scores nor the blood level of citrulline at fever onset was associated with MBI-LCBI. In the multivariable analysis, MASCC-score (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.05 to 1.29 per point decrease), intensive chemotherapy (OR 3·81, 95% CI 2.10 to 6.90) and Pichia kudriavzevii (formerly Candida krusei) colonisation (OR 5.40, 95% CI 1.75 to 16.7) were retained as risk factors for MBI-LCBI, while quinolone use seemed protective (OR 0.42, 95% CI 0.20 to 0.92). Citrulline level (OR 1.57, 95% CI 1.07 to 2.31 per µmol/L decrease), active chronic obstructive pulmonary disease (OR 15.4, 95% CI 1.61 to 14.7) and colonisation with fluconazole-resistant Candida (OR 8.54, 95% CI 1.51 to 48.4) were associated with candidaemia.

CONCLUSION

In haematology patients with fever during neutropenia, hypocitrullinaemia at fever onset was associated with candidaemia, but not with bacterial MBI-LCBI. Patients with intensive chemotherapy with a low MASCC-score and colonisation with Pichia kudriavzevii had the highest risk of MBI-LCBI.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02149329) at 19-NOV-2014.

Selected phytocannabinoids inhibit SN-38- and cytokine-evoked increases in epithelial permeability and improve intestinal barrier function in vitro

Irinotecan use is linked to the development of gastrointestinal toxicity and inflammation, or gastrointestinal mucositis. Selected phytocannabinoids have been ascribed anti-inflammatory effects in models of gastrointestinal inflammation, associated with maintaining epithelial barrier function. We characterised the mucoprotective capacity of the phytocannabinoids: cannabidiol, cannabigerol, cannabichromene and cannabidivarin in a cell-based model of intestinal epithelial stress occurring in mucositis. Transepithelial electrical resistance (TEER) was measured to determine changes in epithelial permeability in the presence of SN-38 (5 μM) or the pro-inflammatory cytokines TNFα and IL-1β (each at 100 ng/mL), alone or with concomitant treatment with each of the phytocannabinoids (1 μM). The DCFDA assay was used to determine the ROS-scavenging ability of each phytocannabinoid following treatment with the lipid peroxidant tbhp (200 μM). Each phytocannabinoid provided significant protection against cytokine-evoked increases in epithelial permeability. Cannabidiol, cannabidivarin and cannabigerol were also able to significantly inhibit SN-38-evoked increases in permeability. None of the tested phytocannabinoids inhibited tbhp-induced ROS generation. These results highlight a novel role for cannabidiol, cannabidivarin and cannabigerol as inhibitors of SN-38-evoked increases in epithelial permeability and support the rationale for the further development of novel phytocannabinoids as supportive therapeutics in the management of irinotecan-associated mucositis.

Benzimidazole Derivative (N-{4-[2-(4-Methoxyphenyl)-1H-Benzimidazole-1-Sulfonyl] Phenyl} Acetamide) Ameliorates Methotrexate-Induced Intestinal Mucositis by Suppressing Oxidative Stress and Inflammatory Markers in Mice

Methotrexate (MTX)-induced intestinal mucositis (IM) is a common side effect in cancer treatment that impairs the immune system and gut microbes, resulting in loss of mucosal integrity and gut barrier dysfunction. The quality of life and outcomes of treatment are compromised by IM. The present study was designed to investigate the mucoprotective potential of the benzimidazole derivative N-{4-[2-(4-methoxyphenyl)-1H-benzimidazole-1-sulfonyl] phenyl} acetamide (B8) on MTX-induced IM in mice. IM was induced by a single dose of MTX in mice and assessed by physical manifestations as well as biochemical, oxidative, histological, and inflammatory parameters. B8 (1, 3, 9 mg/kg) significantly reduced diarrhea score, mitigated weight loss, increased feed intake and, survival rate in a dose-dependent manner. Notably, B8 exhibited a mucoprotective effect evident through the mitigation of villus atrophy, crypt hypoplasia, diminished crypt mitotic figures, mucin depletion, and oxidative stress markers (GSH, SOD, MDA, and catalase concentration). Gene expression analysis revealed that B8 downregulated the mRNA expression of tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), IL-1β, and nuclear factor-κB (NF-κB) and concurrently upregulated IL-10 expression in contrast to the MTX group. Further, B8 significantly improved the luminal microflora profile by augmenting the growth of Lactobacillus spp. and reducing the number of pathogenic bacteria (E. coli). Additionally, the enzyme-linked immunoassay showed that B8 decreased the levels of pro-inflammatory cytokines. Our findings suggest that B8 had mucoprotective effects against MTX-induced IM and could be used as an adjunct in chemotherapy to deter this side effect.

Updated perspectives on the contribution of the microbiome to the pathogenesis of mucositis using the MASCC/ISOO framework

Advances in the treatment of cancer have significantly improved mortality rates; however, this has come at a cost, with many treatments still limited by their toxic side effects. Mucositis in both the mouth and gastrointestinal tract is common following many anti-cancer agents, manifesting as ulcerative lesions and associated symptoms throughout the alimentary tract. The pathogenesis of mucositis was first defined in 2004 by Sonis, and almost 20 years on, the model continues to be updated reflecting ongoing research initiatives and more sophisticated analytical techniques. The most recent update, published by the Multinational Association for Supportive Care in Cancer and the International Society for Oral Oncology (MASCC/ISOO), highlights the numerous co-occurring events that underpin mucositis development. Most notably, a role for the ecosystem of microorganisms that reside throughout the alimentary tract (the oral and gut microbiota) was explored, building on initial concepts proposed by Sonis. However, many questions remain regarding the true causal contribution of the microbiota and associated metabolome. This review aims to provide an overview of this rapidly evolving area, synthesizing current evidence on the microbiota's contribution to mucositis development and progression, highlighting (i) components of the 5-phase model where the microbiome may be involved, (ii) methodological challenges that have hindered advances in this area, and (iii) opportunities for intervention.

Pediococcus pentosaceus PP34 Ameliorates 5-Fluorouracil-Induced Intestinal Mucositis via Inhibiting Oxidative Stress and Restoring the Gut Microbiota

Chemotherapy-induced intestinal mucositis based on 5-fluorouracil (5-FU) slows down the progress of cancer treatment and causes significant suffering to patients. Pediococcus pentosaceus (P. pentosaceus), as a type of LAB, has a range of probiotic properties, including antioxidant, immune benefits, and cholesterol-lowering effects, which are attracting increasing attention. However, studies on the protective effect of P. pentosaceus against chemotherapeutic-induced intestinal mucositis caused by 5-FU remain unclear. Therefore, this study aimed to investigate the potential relieving effects of P. pentosaceus PP34 on 5-FU-induced intestinal mucositis and its mechanism. In the present study, a P. pentosaceus PP34 solution (2 × 109 CFU/mL) was administered daily by gavage followed by intraperitoneal injection of 5-FU to model intestinal mucositis. The body weight, serum biochemical indices, jejunal pathological organization, and expression levels of inflammatory cytokines in the jejunum were examined. The results indicated that the mice induced with 5-FU developed typical intestinal mucositis symptoms and histopathological changes with intense inflammatory and oxidative responses. Moreover, the gut microbiota was disturbed, while PP34 effectively decreased the oxidative reactions and the expression levels of inflammatory mediators and regulated the gut microbiota in 5-FU-exposed mice. Taken together, the study indicated that P. pentosaceus PP34 ameliorates 5-Fluorouracil-induced intestinal mucositis via inhibiting oxidative stress and restoring the gut microbiota.

Microbiome in radiotherapy: an emerging approach to enhance treatment efficacy and reduce tissue injury

Radiotherapy is a widely used cancer treatment that utilizes powerful radiation to destroy cancer cells and shrink tumors. While radiation can be beneficial, it can also harm the healthy tissues surrounding the tumor. Recent research indicates that the microbiota, the collection of microorganisms in our body, may play a role in influencing the effectiveness and side effects of radiation therapy. Studies have shown that specific species of bacteria living in the stomach can influence the immune system's response to radiation, potentially increasing the effectiveness of treatment. Additionally, the microbiota may contribute to adverse effects like radiation-induced diarrhea. A potential strategy to enhance radiotherapy outcomes and capitalize on the microbiome involves using probiotics. Probiotics are living microorganisms that offer health benefits when consumed in sufficient quantities. Several studies have indicated that probiotics have the potential to alter the composition of the gut microbiota, resulting in an enhanced immune response to radiation therapy and consequently improving the efficacy of the treatment. It is important to note that radiation can disrupt the natural balance of gut bacteria, resulting in increased intestinal permeability and inflammatory conditions. These disruptions can lead to adverse effects such as diarrhea and damage to the intestinal lining. The emerging field of radiotherapy microbiome research offers a promising avenue for optimizing cancer treatment outcomes. This paper aims to provide an overview of the human microbiome and its role in augmenting radiation effectiveness while minimizing damage.

Application of In Situ Mucoadhesive Hydrogel with Anti-Inflammatory and Pro-Repairing Dual Properties for the Treatment of Chemotherapy-Induced Oral Mucositis

Chemotherapy-induced oral mucositis (CIOM) is a prevalent complication of chemotherapy and significantly affects the treatment process. However, effective treatment for CIOM is lacking due to the unique environment of the oral cavity and the single effect of current drug delivery systems. In this present study, we propose an innovative approach by combining a methacrylate-modified human recombinant collagen III (rhCol3MA) hydrogel system with hyaluronic acid-epigallocatechin gallate (HA-E) and dopamine-modified methacrylate-alginate (AlgDA-MA). HA-E is used as an antioxidant and anti-inflammatory agent and synergizes with AlgDA-MA to improve the wet adhesion of hydrogel. The results of rhCol3MA/HA-E/AlgDA-MA (Col/HA-E/Alg) hydrogel demonstrate suitable physicochemical properties, excellent wet adhesive capacity, and biocompatibility. Notably, the hydrogel could promote macrophage polarization from M1 to M2 and redress human oral keratinocyte (HOK) inflammation by inhibiting NF-κB activation. Wound healing evaluations in vivo demonstrate that the Col/HA-E/Alg hydrogel exhibits a pro-repair effect by mitigating inflammatory imbalances, fostering early angiogenesis, and facilitating collagen repair. In summary, the Col/HA-E/Alg hydrogel could serve as a promising multifunctional dressing for the treatment of CIOM.

Novel insights into gut health: Cilostazol strengthens gut integrity by adjusting TLR-2/NF-κB/IL-23 and CD44/AKT/GSK-3β/cyclin-D1 trajectories in methotrexate-induced mucositis model

Methotrexate (MTX)-induced gastrointestinal mucositis is a common adverse effect characterized by redox imbalance and overproduction of inflammatory mediators that perturb intestinal integrity. Currently, there is no definitive treatment for this condition and its prevention is still far beyond comprehension. Because of its pleiotropic pharmacological actions, we aimed to explore the potential mechanisms through which cilostazol (CILO) can protect against MTX-induced intestinal mucositis. Wistar rats were allocated into 4 groups, control, CILO (100 mg/kg, p.o for 14 days), MTX (7.5 mg/kg for 4 successive days), and CILO + MTX. The improving effect of CILO on the morphological structure was confirmed by an upturn in the histopathological and transition electron microscope examinations evidenced by the increased jejunal villus height/width and the crypt depth besides the maintenance of tight junctions. These findings were verified biochemically; on the molecular level, CILO reduced the MTX-induced lipid peroxidation, cleaved caspase-3, p53, and the inflammatory parameters (TLR-2, NF-κB, IL-23, TNF-α, IL-1β), while increasing the anti-inflammatory marker IL-10 and the antioxidant enzyme SOD. Moreover, CILO decreased the injurious axis AKT/GSK-3β/cyclin-D1, and CD44+, but increased the immunoexpression of the cell proliferating marker PCNA. CILO also upheld the intestinal barrier by enhancing the tight junction molecules (ZO-1, claudin-4) and the E-cadherin/β-catenin complex while abating the mesenchymal marker vimentin. In conclusion, CILO protected gut integrity by reducing the epithelial-mesenchymal transition process, the MTX-induced oxidative, apoptotic, and inflammatory mediators, and turning off the CD44/AKT/GSK-3β/cyclin D1 trajectory and intensifying the expression of PCNA.

Recent advances in cancer therapy-associated oral mucositis

Oral mucositis (OM) is a common and debilitating toxicity of cancer treatments - chemotherapy, radiotherapy, hematopoietic cell transplant, or combinations. OM is associated with severe oral pain and has negative impacts on patient function and quality of life. Additionally, OM has accompanying systemic complications that may have critical implications. These local and systemic consequences can alter cancer treatment, and add an economic burden. This review covers the clinical presentation and course of OM, differential diagnosis, clinical and economic impacts, pathogenesis, risk factors, assessment measures, biomarkers and prediction of OM, management, research advances in the development of new drugs and treatments, and big data.

In vitro cytoprotective and in vivo anti-oral mucositis effects of melatonin and its derivatives

According to our preliminary study, melatonin and its N-amide derivatives (N-(2-(1-4-bromobenzoyl-5-methoxy-1H-indol-3-yl)ethyl)acetamide (BBM) and 4-bromo-N-(2-(5-methoxy-1H-indol-3-yl)ethyl)benzamide (EBM)) inhibited the marker of acute inflammation in tests in vitro and in vivo. The anti-inflammatory agent is intended for the prevention and treatment of chemotherapy-induced toxicity. In this study aimed to evaluate the effect of melatonin and its derivatives on mechanisms related to chemotherapy-induced oral mucositis by in vitro ROS and 5-FU-induced human keratinocyte cells as well as in vivo oral mucositis model. In in vitro H2O2-induced HaCaT cells, BBM had the highest level of protection (34.57%) at a concentration 50 µM, followed by EBM (26.41%), and melatonin (7.9%). BBM also protected cells against 5-FU-induced to 37.69-27.25% at 12.5-100 µM while EBM was 36.93-29.33% and melatonin was 22.5-11.39%. In in vivo 5-FU-induced oral mucositis in mice, melatonin, BBM, and EBM gel formulations protected tissue damage from 5-FU similar to the standard compound, benzydamine. Moreover, the weight of mice and food consumption recovered more quickly in the BBM group. These findings suggested that it was possible to develop BBM and EBM as new therapeutic agents for the treatment of oral mucositis.

Elemental diet preventative effects for adverse events during chemotherapy in patients with esophageal cancer - A systematic review and meta-analysis

Introduction

The effectiveness of an elemental diet (ED) for preventing adverse events (AEs) during chemotherapy for patients with esophageal cancer (EC) remains unclear. The aim of this meta-analysis was to comprehensively assess the efficacy of ED for preventing AE in EC patients during chemotherapy. Medline (via PubMed), Embase, the Cochrane Library, and Web of Science were searched to retrieve prospective and randomized studies published before April 12, 2023. The odds ratio (OR) of each AE was calculated using Review Manger 5.4.1. The risk of bias was assessed, and a random effect model-based meta-analysis was used to analyze the available data. Four prospective and randomized studies involving 237 patients were identified after a systematic search. Regarding gastrointestinal toxicities, the findings indicated a trend toward a decrease in the risk of mucositis (OM) (OR = 0.54, 95 % CI: 0.25-1.14), constipation (OR = 0.87, 95 % CI: 0.49-1.53), and anorexia (OR = 0.99, 95 % CI: 0.32-3.05), as well as an increasing trend in the risk of diarrhea (OR = 1.48, 95 % CI: 0.79-2.79), among patients treated with ED. However, none of these reached statistical significance. For hematological toxicities, the risk of all-grade neutropenia (OR = 0.28, 95 % CI: 0.14-0.57), grade ≥ 2 leucopenia (OR = 0.43, 95 % CI: 0.22-0.84), grade ≥ 2 neutropenia (OR = 0.34, 95 % CI: 0.17-0.67), and grade ≥ 3 neutropenia (OR = 0.28, 95 % CI: 0.12-0.63) was significantly decreased. There is no firm evidence confirming the preventive effect of an ED against OM or diarrhea. However, an ED may potentially be helpful in preventing neutropenia and leucopenia.

An unmet need for pharmacology: Treatments for radiation-induced gastrointestinal mucositis

Gastrointestinal mucositis (GIM) continues to be a significant issue in the management of abdominal cancer radiation treatments and chemotherapy, causing significant patient discomfort and therapy interruption or even cessation. This review will first focus on radiotherapy induced GIM, providing an understanding of its clinical landscape. Subsequently, the aetiology of GIM will be reviewed, highlighting diverse contributing factors. The cellular and tissue damage and associated molecular responses in GIM will be summarised in the context of the underlying complex biological processes. Finally, available drugs and pharmaceutical therapies will be evaluated, underscoring their insufficiency, and highlighting the need for further research and innovation. This review will emphasize the urgent need for improved pharmacologic therapeutics for GIM, which is a key research priority in oncology.

Recombinant Human Keratinocyte Growth Factor Ameliorates Cancer Treatment-Induced Oral Mucositis on a Chip

Oral mucositis (OM) is a severe complication of cancer therapies caused by off-target cytotoxicity. Palifermin, which is recombinant human keratinocyte growth factor (KGF), is currently the only mitigating treatment available to a subset of OM patients. This study used a previously established model of oral mucositis on a chip (OM-OC) comprised of a confluent human gingival keratinocytes (GIE) layer attached to a basement membrane-lined subepithelial layer consisting of human gingival fibroblasts (HGF) and human dermal microvascular endothelial cells (HMEC) on a stable collagen I gel. Cisplatin, radiation, and combined treatments are followed by a recovery period in the OM-OC to determine possible cellular and molecular mechanisms of OM under effects of KGF. Cancer treatments affected the keratinocyte layer, causing death and epithelial barrier loss. Both keratinocytes and subepithelial cells died rapidly, as evidenced by propidium iodide staining. In response to radiation exposure, cell death occurred in the apical epithelial layer, predominantly, within 24h. Cisplatin exposure predominantly promoted death of basal epithelial cells within 32-36h. Presence of KGF in OM-OC protected tissues from damage caused by cancer treatments in a dose-dependent manner, being more effective at 10 ng/mL. As verified by F-actin staining and the Alamar Blue assay, KGF contributed to epithelial survival and induced proliferation of GIE and HGF as well as HMEC within 120h. When the expression of eighty inflammatory cytokines is evaluated at OM induction (Day 12) and resolution (Day 18) stages in OM-OC, some cytokines are identified as potential novel therapeutic targets. In comparison with chemoradiation exposure, KGF treatment showed a trend to decrease IL-8 and TNF-a expression at Day 12 and 18, and TGF-β1 at Day 18 in OM-OC. Taken together, these findings support the utility of OM-OC as a platform to model epithelial damage and evaluate molecular mechanisms following OM treatment.