Alleviating mucositis: are we on track for a novel therapeutic?

Effects of 10.6-μm laser moxibustion and electroacupuncture at ST36 in a 5-Fu-induced diarrhea rat model

OBJECTIVE

The aim of this study was to investigate the effect of 10.6-μm laser moxibustion and electroacupuncture in 5-fluorouracil (5-Fu)-induced diarrhea model rats.

METHODS

Forty-eight Sprague Dawley rats were randomly divided into 4 groups: a normal group, model group, 10.6-μm laser moxibustion (LM) group, and electroacupuncture (EA) group. Diarrhea was induced by 5-Fu (50 mg/kg) injection in 36 rats; the LM and EA groups received treatment at acupoint ST36 (Zusanli) on hind limbs once a day for 6 days.

RESULTS

5-Fu injection caused body weight decline and diarrhea. From the 5th to 7th day, the LM group showed higher body weights than the model group (P < 0.05). On the 6th day, diarrhea score of the LM group was better than that of the EA group (P < 0.05). Both scores of the LM group and EA group were better than that of model group (P < 0.05). The LM group and EA group both had better intestine pathological scores and lower endotoxin (ET) and diamine oxide (DAO) activity than the model group (P < 0.01). The LM group got better pathological scores than the EA group (P < 0.01). Ultramicroscopic structures of the model group showed severe damage while the LM group and EA group remained good in their small intestines. The model group had obviously decreased occludin protein in intestine tissues than the control group (P < 0.01), while occludin expressions in the LM group and EA group were both obviously increased compared with the model group (P < 0.01).

CONCLUSION

LM and EA treatment on ST36 could alleviate damage to intestinal barrier function and alleviate diarrhea caused by 5-Fu.

Patient and oncologist perceptions regarding symptoms and impact on quality-of-life of oral mucositis in cancer treatment: results from the Awareness Drives Oral Mucositis PercepTion (ADOPT) study

PURPOSE

This descriptive cross-sectional survey aims to assess the level of concordance between the perspectives of oncologists and those of patients regarding oral mucositis (OM) symptoms, and the impact of OM on various aspects of daily living and concurrent cancer management.

METHODS

Oncologists involved in OM management (n = 105), and patients who developed OM during cancer treatment (n = 175), were recruited from seven Asian countries. Oncologists completed a face-to-face, quantitative interview; patients completed a face-to-face interview, and a self-reported questionnaire.

RESULTS

Oncologists and patients ranked treatment-induced OM among the three most important toxicities of cancer therapy requiring intervention. The most frequent OM symptoms reported by patients were oral ulcers (74%), dry mouth (73%), and difficulty swallowing (62%). Oncologists expected mild OM symptoms to last slightly longer than 1 week, whereas patients reported mild symptoms for more than 2 weeks. In mild-to-moderate OM, oncologists underestimated patients' pain experience. Overall, only 45% of oncologists said they would initiate OM prophylaxis when cancer therapy started. Of the 87% of patients who said they used their prescribed medications, only 16% reported using prophylactically prescribed medication. While oncologists' concerns related to the delays and interruptions of cancer treatment, patients tended to focus on the effects of OM on eating, drinking, and talking.

CONCLUSIONS

Oncologists' and patients' perceptions about treatment-induced OM differ. To overcome discordant perspectives, there is a need to raise general awareness and improve proactive management of OM. As noted in recent guidelines, supportive cancer care is critical for ensuring optimal therapy and for improving the patient's experience.

Melatonin protects rats from radiotherapy-induced small intestine toxicity

Radiotherapy-induced gut toxicity is among the most prevalent dose-limiting toxicities following radiotherapy. Prevention of radiation enteropathy requires protection of the small intestine. However, despite the prevalence and burden of this pathology, there are currently no effective treatments for radiotherapy-induced gut toxicity, and this pathology remains unclear. The present study aimed to investigate the changes induced in the rat small intestine after external irradiation of the tongue, and to explore the potential radio-protective effects of melatonin gel. Male Wistar rats were subjected to irradiation of their tongues with an X-Ray YXLON Y.Tu 320-D03 irradiator, receiving a dose of 7.5 Gy/day for 5 days. For 21 days post-irradiation, rats were treated with 45 mg/day melatonin gel or vehicle, by local application into their mouths. Our results showed that mitochondrial oxidative stress, bioenergetic impairment, and subsequent NLRP3 inflammasome activation were involved in the development of radiotherapy-induced gut toxicity. Oral treatment with melatonin gel had a protective effect in the small intestine, which was associated with mitochondrial protection and, consequently, with a reduced inflammatory response, blunting the NF-κB/NLRP3 inflammasome signaling activation. Thus, rats treated with melatonin gel showed reduced intestinal apoptosis, relieving mucosal dysfunction and facilitating intestinal mucosa recovery. Our findings suggest that oral treatment with melatonin gel may be a potential preventive therapy for radiotherapy-induced gut toxicity in cancer patients.

May cannabinoids prevent the development of chemotherapy-induced diarrhea and intestinal mucositis? Experimental study in the rat

BACKGROUND

The antineoplastic drug 5-fluoruracil (5-FU) is a pirimidine analog, which frequently induces potentially fatal diarrhea and mucositis. Cannabinoids reduce gastrointestinal motility and secretion and might prevent 5-FU-induced gut adverse effects. Here, we asked whether cannabinoids may prevent diarrhea and mucositis induced by 5-FU in the rat.

METHODS

Male Wistar rats received vehicle or the non-selective cannabinoid agonist WIN 55,212-2 (WIN; 0.5 mg kg^-1 injection^-1 , 1 injection day^-1 , 4 consecutive days) by intraperitoneal (ip) route; on the first 2 days, animals received also saline or 5-FU (150 mg kg^-1 injection^-1 , cumulative dose of 300 mg kg^-1 ). Gastrointestinal motor function was radiographically studied after barium contrast intragastric administration on experimental days 1 and 4. Structural alterations of the stomach, small intestine and colon were histologically studied on day 4. PAS staining and immunohistochemistry for Ki67, chromogranin A and CD163 were used to detect secretory, proliferating, and endocrine cells, and activated macrophages respectively.

KEY RESULTS

As shown radiographically, 5-FU induced significant gastric emptying delay (on days 1 and 4) and diarrhea (on day 4). WIN did not significantly alter the motility curves obtained for either control or 5-FU-treated animals but tended to reduce the severity of 5-FU-induced diarrhea and increased permanence of barium from day 1 to the beginning of day 4 in 5-FU-treated animals. 5-FU-induced mucositis was severe and not counteracted by WIN.

CONCLUSIONS AND INFERENCES

5-FU-induced diarrhea, but not mucositis, was partly prevented by WIN at a low dose. Cannabinoids might be useful to prevent chemotherapy-induced diarrhea.

A new animal model of intestinal mucositis induced by the combination of irinotecan and 5-fluorouracil in mice

PURPOSE

Intestinal mucositis (IM) is a common side effect of anticancer agents. Despite polychemotherapy use in clinical practice, the pathogenesis of IM has been investigated in single drug injection animal models. However, the progression of IM could vary according to drug regimens. Thus, we aimed to develop a new experimental mucositis model induced by combining irinotecan and 5-fluorouracil (5-FU) treatments.

METHODS

IM was induced in male C57BL/6 mice by the intraperitoneal administration of either 0.9 % saline (5 mL/kg), irinotecan (IRI, 30 or 45 mg/kg), 5-FU (25, 37.5, or 50 mg/kg), or the combination of these doses (IRI + 5-FU) for 4 days. Animal survival, body mass variation, and diarrhea scores were evaluated daily. On the 7th day, the mice were euthanized, and intestinal samples were collected for histopathology and morphometric analysis, as well as for the determination of myeloperoxidase activity and cytokine dosage (TNF-α and IL-6).

RESULTS

The optimal dose combination that induced IM and presented no substantial mortality on the 7th day was IRI (45 mg/kg) + 5-FU (37.5 mg/kg), which was used for subsequent studies. IRI and 5-FU in combination induced significant diarrhea, body weight loss, intestinal damage, inflammatory cell infiltration, and increased levels of cytokines when compared with other groups (P < 0.05). Neither IRI nor 5-FU alone induced IM.

CONCLUSIONS

We developed a new experimental model of IM induced by combining irinotecan and 5-FU treatments, which will allow us to gain a better knowledge concerning the pathogenesis of this disease through the pharmacological modulation of key inflammatory mediators.

Oral Mucositis Induced By Anticancer Therapies

Oral mucositis induced by conventional cytotoxic cancer therapies is a common and significant clinical problem in oncology. Mucositis symptoms, which include severe pain, may lead to dose reductions and unplanned interruptions of chemotherapy and/or radiotherapy, and often affect patients' quality of life. In addition, ulcerative mucositis represents a risk factor for local or systemic infectious complications that may be life-threatening in immunosuppressed patients. The development of biologically based targeted cancer therapies, which aim to block the growth, spread, and survival of tumors by interfering with specific molecular targets, may have reduced mucosal injury, but did not eliminate it. This article will review the epidemiology, pathobiology, and management of oral mucositis associated with conventional cytotoxic therapies for malignant diseases and will briefly summarize emerging information on oral mucosal injury associated with targeted therapies. Considerations for future research aimed at the development of more efficient and effective supportive care approaches will be presented, with emphasis on the contribution of dental researchers and clinicians in these efforts.