Complementary strategies for the management of radiation therapy side effects

Radiotherapy-Induced Fatigue in Breast Cancer Patients

Background

A large proportion of breast cancer patients who undergo adjuvant radiotherapy suffer from radiotherapy-induced fatigue. The possible causative factors of this specific side effect are diverse.

Summary

Prevalence, duration, and severity of radiotherapy-induced fatigue are dependent on the type of radiotherapy, as well as on the irradiated volume, dose scheme, on the number of radiation fields, the combination with other treatments, diurnal rhythm, smoking, and time-to-hospitalization. Recommended treatments include non-pharmacologic interventions, such as physical and psychosocial interventions. Pharmacologic therapies include treatment with methylphenidate and modafinil. In addition to its early detection with standardized instruments, adequate education to breast cancer patients about risks and predisposing factors of radiotherapy-induced fatigue is essential. Multidimensional strategies help to maintain the patients' quality of life and therefore guarantee treatment adherence and efficacy.

Key Messages

Radiotherapy-induced fatigue is an underreported, underdiagnosed, and undertreated side effect. This review provides an overview of radiotherapy-induced fatigue in breast cancer patients receiving adjuvant radiotherapy.

Effective Gold Nanoparticle-Antibody-Mediated Drug Delivery for Photodynamic Therapy of Lung Cancer Stem Cells

Cancer stem cells (CSCs) are a leading contributor to lung cancer mortality rates. CSCs are responsible for tumor growth and recurrence through inhibition of drug-induced cell death, decreasing the effect of traditional cancer therapy and photodynamic therapy (PDT). PDT can be improved to successfully treat lung cancer by using gold nanoparticles (AuNPs), due to their size and shape, which have been shown to facilitate drug delivery and retention, along with the targeted antibody (Ab) mediated selection of CSCs. In this study, a nanobioconjugate (NBC) was constructed, using a photosensitizer (PS) (AlPcS₄Cl), AuNPs and Abs. The NBC was characterized, using spectroscopy techniques. Photodynamic effects of the NBC on lung CSCs was evaluated, using biochemical assays 24 h post-irradiation, in order to establish its anticancer effect. Results showed successful conjugation of the nanocomposite. Localization of the NBC was seen to be in integral organelles involved in cell homeostasis. Biochemical responses of lung CSCs treated using AlPcS₄Cl-AuNP and AlPcS₄Cl-AuNP-Ab showed significant cell toxicity and cell death, compared to free AlPcS₄Cl. The PDT effects were enhanced when using the NBC, showing significant lung CSC destruction to the point of eradication.

Inflammation-Induced Tryptophan Breakdown is Related With Anemia, Fatigue, and Depression in Cancer

Many patients with cancer suffer from anemia, depression, and an impaired quality of life (QoL). These patients often also show decreased plasma tryptophan levels and increased kynurenine concentrations in parallel with elevated concentrations of Th1 type immune activation marker neopterin. In the course of anti-tumor immune response, the pro-inflammatory cytokine interferon gamma (IFN-γ) induces both, the enzyme indoleamine 2,3-dioxygenase (IDO) to degrade tryptophan and the enzyme GTP-cyclohydrolase I to form neopterin. High neopterin concentrations as well as an increased kynurenine to tryptophan ratio (Kyn/Trp) in the blood of cancer patients are predictive for a worse outcome. Inflammation-mediated tryptophan catabolism along the kynurenine pathway is related to fatigue and anemia as well as to depression and a decreased QoL in patients with solid tumors. In fact, enhanced tryptophan breakdown might greatly contribute to the development of anemia, fatigue, and depression in cancer patients. IDO activation and stimulation of the kynurenine pathway exert immune regulatory mechanisms, which may impair anti-tumor immune responses. In addition, tumor cells can degrade tryptophan to weaken immune responses directed against them. High IDO expression in the tumor tissue is associated with a poor prognosis of patients. The efficiency of IDO-inhibitors to inhibit cancer progression is currently tested in combination with established chemotherapies and with immune checkpoint inhibitors. Inflammation-mediated tryptophan catabolism and its possible influence on the development and persistence of anemia, fatigue, and depression in cancer patients are discussed.

Anticancer effect of S-allyl-L-cysteine via induction of apoptosis in human bladder cancer cells

To examine the anticancer effects of S-allyl-L-cysteine (SAC) in human bladder cancer cells and to identify possible molecular mechanisms, bladder cancer cell lines (HTB5, HTB9, JON, UMUC14, T24, and cisplatin resistant-T24R2) were incubated with SAC, and cell proliferation was measured using the Cell Counting Kit-8 assay and clonogenic assay. Cell cycle and apoptosis were evaluated by flow cytometry. Expression levels of apoptosis- and cell cycle-associated proteins were analyzed by western blotting. Proliferation and colony formation in bladder cancer cells was significantly inhibited by SAC treatment in a dose-dependent manner. SAC treatment significantly enhanced apoptosis and promoted a cell cycle arrest in the S phase. SAC also increased the expression of apoptosis-related genes, including caspases, poly (ADP-ribose) polymerase and cytochrome c. SAC had an anticancer effect on bladder cancer cells in vitro, at least partially, through the induction of apoptosis and a cell cycle arrest. SAC is a potential therapeutic agent for the treatment of bladder cancer.

Preventive Effect of Glycyrrhiza Glabra Extract on Oral Mucositis in Patients Under Head and Neck Radiotherapy: A Randomized Clinical Trial

OBJECTIVES

About two-thirds of cancer patients undergo radiotherapy. Oral mucositis represents a major complication of radiotherapy, causing morbidity and mortality and decreasing the quality of life of patients. This study aimed to assess the preventive effect of Glycyrrhiza aqueous extract on oral mucositis in cancer patients under head and neck radiotherapy.

MATERIALS AND METHODS

In this double-blind clinical trial, 37 head and neck cancer patients were divided into intervention (n=19) group receiving Glycyrrhiza aqueous extract and control (n=18) group receiving placebo. Patients in the test group used Glycyrrhiza aqueous extract topically twice a day from the first day of starting radiotherapy until the end of the second week. Patients were examined in the first day of radiotherapy for any type of wound before treatment and those with oral ulcers before radiotherapy were excluded from the study. The grade of mucositis was determined using the classification by the World Health Organization. ANCOVA was performed to assess any difference between the two groups with regard to oral mucosal irritation and wound size after the intervention while controlling for the covariates such as sex and age.

RESULTS

Significant differences were found in the maximum grade of mucositis and oral mucosal irritation between the intervention and control groups (P<0.001).

CONCLUSIONS

This study showed that aqueous extract of Glycyrrhiza can be effective for decreasing the severity of oral mucositis in head and neck cancer patients undergoing radiotherapy.

The Etiology and management of radiotherapy-induced fatigue

Fatigue is one of the most common side-effects accompanying radiotherapy, but arguably the least understood. Radiotherapy-induced fatigue (RIF) is a clinical subtype of cancer treatment-related fatigue. It is described as a pervasive, subjective sense of tiredness persisting over time, interferes with activities of daily living, and is not relieved by adequate rest or sleep. RIF is one of the early side-effects and long-lasting for cancer patients treated with localized radiation. Although the underlying mechanisms of fatigue have been studied in several disease conditions, the etiology, mechanisms, and risk factors of RIF remain elusive, and this symptom remains poorly managed. The purpose of this paper is to review and discuss recent articles that defined, proposed biologic underpinnings and mechanisms to explain the pathobiology of RIF, as well as articles that proposed interventions to manage RIF. Understanding the mechanisms of RIF can describe promising pathways to identify at-risk individuals and identify potential therapeutic targets to alleviate and prevent RIF using a multimodal, multidisciplinary approach.

The Practical Consideration of Poliovirus as an Oncolytic Virotherapy

The inauguration of novel treatment strategies into the clinical setting faces a number of hurdles. In addition to treatment efficacy and safety, acceptance by doctors and patients is paramount to the success of novel therapies. Although viruses are the cause of numerous infectious diseases, these acellular entities have been harnessed over the years to benefit mankind. Recently, a recombinant Poliovirus-Rhinovirus Chimera (PVSRIPO) has shown promise for the treatment of glioblastoma in clinical trials as well as other cancer types in animal models. In this literature review, we discuss the use of PVSRIPO as an oncolytic virotherapy. In addition to being a potential treatment for glioblastoma, this recombinant virus could possibly be used against other cancers because many tumor cells express the PVSRIPO receptor antigens (CD155) and have a limited ability to control viral replication. Moreover, virus-induced immune responses contribute to the efficacy of PVSRIPO. Given the current trajectory of this experimental therapy, the possibility exists that PVSRIPO will soon be a viable treatment option for various cancer types. While many healthcare providers and cancer patients likely welcome this new viral based treatment, history has taught us that some may be skeptical and avoid its use because of the viral composition of this therapy.