Amifostine modulates radio-induced apoptosis of peripheral blood lymphocytes in head and neck cancer patients

Efficacy of Shenglin decoction in preventing acute severe lymphocytopenia in patients with non-small cell lung cancer undergoing concurrent chemoradiotherapy: a study protocol for a randomized controlled trial

Background

Definitive concurrent chemoradiotherapy (CCRT) followed by maintenance therapy with immune checkpoint inhibitors offers the best chance of cure for patients with stage III non-small cell lung cancer (NSCLC). A significant challenge in this regimen is the occurrence of acute severe lymphopenia (ASL), which can compromise treatment efficacy. Currently, there are no effective strategies for preventing and treating ASL. Shenglin decoction (SLD), a traditional Chinese herbal medicine formulation, has demonstrated preliminary efficacy in mitigating ASL. However, robust evidence from clinical trials and a clear understanding of its mechanism of action are still needed. This study aims to comprehensively assess the efficacy, safety, and underlying mechanisms of SLD in the prevention of ASL.

Methods

This prospective, dual-center, open-label, randomized controlled trial will enroll 140 stage III NSCLC patients. Participants will be randomly allocated in a 1:1 ratio to a control group or an experimental group. Both groups will undergo definitive CCRT. Alongside the commencement of CCRT, the experimental group will receive an additional oral SLD intervention for a duration of three months. The primary outcome is the incidence rate of ASL, defined as the proportion of patients who experience at least one instance of a total lymphocyte count falling below 0.5 × 10^9 cells/L within 3 months of initiating CCRT treatment. Additionally, 16S rRNA gene sequencing analysis of fecal samples to assess gut microbiota, as well as metabolomic analysis of fecal/blood samples, will be conducted to explore potential mechanisms.

Discussion

This study protocol aims to rigorously evaluate the efficacy and safety of SLD, as well as elucidate its mechanism of action in preventing ASL. Successful outcomes could establish SLD as an evidence-based intervention for ASL prevention in NSCLC patients undergoing CCRT.

Trial Registration

The trial was registered at the Chinese Clinical Trials Registry (ChiCTR2300071788, https://www.chictr.org.cn/).

Association of neutrophil-to-lymphocyte ratio, radiotherapy fractionation/technique, and risk of development of distant metastasis among patients with locally advanced rectal cancer

BACKGROUND

We investigated the prognostic impact of the neutrophil-to-lymphocyte ratio (NLR) in patients with locally advanced rectal cancer (LARC) and whether modifiable factors in radiotherapy (RT) influenced the NLR.

METHODS

Data of 1386 patients who were treated with neoadjuvant RT and concurrent or sequential chemotherapy for LARC between 2006 and 2019 were evaluated. Most patients (97.8%) were treated with long-course RT (LCRT; 50-50.4 Gy in 25-28 fractions) using three-dimensional conformal radiotherapy (3D-CRT) (n = 851) or helical tomotherapy (n = 504), and 30 patients underwent short-course RT (SCRT; 25 Gy in 5 fractions, followed by XELOX administration for 6 weeks). Absolute neutrophil and lymphocyte counts were obtained at initial diagnosis, before and during the preoperative RT course, and after preoperative concurrent chemoradiotherapy. The primary endpoint was distant metastasis-free survival (DMFS).

RESULTS

The median follow-up time was 61.3 (4.1-173.7) months; the 5-year DMFS was 80.1% and was significantly associated with the NLR after RT but not before. A post-RT NLR ≥ 4 independently correlated with worse DMFS (hazard ratio, 1.42; 95% confidence interval, 1.12-1.80), along with higher ypT and ypN stages. Post-RT NLR (≥ 4) more frequently increased following LCRT (vs. SCRT, odds ratio [OR] 2.77, p = 0.012) or helical tomotherapy (vs. 3D-CRT, OR 1.29, p < 0.001).

CONCLUSIONS

Increased NLR after neoadjuvant RT is associated with increased distant metastasis risk and poor survival outcome in patients with LARC. Moreover, high NLR following RT is directly related to RT fractionation, delivery modality, and tumor characteristics. These results are hypothesis-generating only, and confirmatory studies are required.

Lymphopenia and intratumoral lymphocytic balance in the era of cancer immuno-radiotherapy

INTRODUCTION

The immune response has been recognized as a major tumor-eradication component of radiotherapy.

OBJECTIVE

This review studies, under a clinical perspective, two contrasting effects of radiotherapy, namely immunosuppression and radiovaccination.

MATERIALS AND METHODS

We critically reviewed the available clinical and experimental experience on radiotherapy-induced lymphopenia.

RESULTS

Radiation-induced tumor damage promotes radio-vaccination, enhances cytotoxic immune responses, and potentiates immunotherapy. Nevertheless, radiotherapy induces systemic and intratumoral lymphopenia. The above effects are directly related to radiotherapy fractionation and field size/location, and tumor characteristics.

DISCUSSION

Hypofractionated stereotactic and accelerated irradiation better promotes radio-vaccination and produces less severe lymphopenia. Adopting cytoprotective policies and combining lympho-stimulatory agents or agents blocking regulatory lymphocyte activity are awaited to unmask the radio-vaccination effect, enhancing the efficacy immuno-radiotherapy.

CONCLUSION

Radiation-induced lymphopenia and immunosuppression are important issues that should be considered in the design of immuno-radiotherapy clinical trials.

Effectiveness and safety of different amifostine regimens: Preliminary results of a phase II multicenter randomized controlled trial

Objective

The radioprotective effects of amifostine remain uncertain in patients with nasopharyngeal carcinoma (NPC), and adverse effects and cost limit generalization of its classical everyday regimen. This phase II multicenter randomized controlled trial aimed to explore whether amifostine could ameliorate the toxicities of NPC patients in the era of intensity-modulated radiotherapy (IMRT), and to compare different regimens of amifostine on effectiveness and safety.

Methods

Patients with stage I-IVB NPC were involved prospectively from January 1st, 2013. All patients received radical treatment based on IMRT. After a randomization stratified by their stage, these patients were allocated into 3 groups: the group treated without amifostine, the group treated with the everyday regimen of amifostine, and the group treated with the every-other-day regimen. The 3 groups of patients were compared on radiotherapy-related acute toxicities, treatment effects of NPC, and amifostine-related complications. This trial was registered on the clinicaltrials.gov (ID: NCT01762514).

Results

Until August 31st, 2017, totally 187 patients completed experimental intervention. Only amifostine of everyday regimen appeared to reduce the patient proportion of mucositis (79.1% vs. 96.8%, P=0.002). Hypocalcemia was less common in patients treated without amifostine than in those treated with amifostine (22.6% vs. 53.4% vs. 41.8%, P=0.002). Neither complete remission rates nor the survivals were affected by amifostine.

Conclusions

Amifostine of everyday regimen could reduce mucositis in NPC patients who received IMRT, though it also had the possibility to cause more hypocalcemia.

Chemoradiotherapy-induced upregulation of PD-1 antagonizes immunity to HPV-related oropharyngeal cancer

While viral antigens in human papillomavirus (HPV)-related oropharyngeal cancer (HPVOPC) are attractive targets for immunotherapy, the effects of existing standard-of-care therapies on immune responses to HPV are poorly understood. We serially sampled blood from patients with stage III-IV oropharyngeal cancer undergoing concomitant chemoradiotherapy with or without induction chemotherapy. Circulating immunocytes including CD4(+) and CD8(+) T cells, regulatory T cells (Treg), and myeloid-derived suppressor cells (MDSC) were profiled by flow cytometry. Antigen-specific T-cell responses were measured in response to HPV16 E6 and E7 peptide pools. The role of PD-1 signaling in treatment-related immunosuppression was functionally defined by performing HPV-specific T-cell assays in the presence of blocking antibody. While HPV-specific T-cell responses were present in 13 of 18 patients before treatment, 10 of 13 patients lost these responses within 3 months after chemoradiotherapy. Chemoradiotherapy decreased circulating T cells and markedly elevated MDSCs. PD-1 expression on CD4(+) T cells increased by nearly 2.5-fold after chemoradiotherapy, and ex vivo culture with PD-1-blocking antibody enhanced HPV-specific T-cell responses in 8 of 18 samples tested. Chemoradiotherapy suppresses circulating immune responses in patients with HPVOPC by unfavorably altering effector:suppressor immunocyte ratios and upregulating PD-1 expression on CD4(+) T cells. These data strongly support testing of PD-1-blocking agents in combination with standard-of-care chemoradiotherapy for HPVOPC.

Combined low initial DNA damage and high radiation-induced apoptosis confers clinical resistance to long-term toxicity in breast cancer patients treated with high-dose radiotherapy

Background

Either higher levels of initial DNA damage or lower levels of radiation-induced apoptosis in peripheral blood lymphocytes have been associated to increased risk for develop late radiation-induced toxicity. It has been recently published that these two predictive tests are inversely related. The aim of the present study was to investigate the combined role of both tests in relation to clinical radiation-induced toxicity in a set of breast cancer patients treated with high dose hyperfractionated radical radiotherapy.

Methods

Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma treated with high-dose hyperfractioned radical radiotherapy. Acute and late cutaneous and subcutaneous toxicity was evaluated using the Radiation Therapy Oncology Group morbidity scoring schema. The mean follow-up of survivors (n = 13) was 197.23 months. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radiation-induced apoptosis (RIA) at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide.

Results

Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). Radiation-induced apoptosis increased with radiation dose (median 12.36, 17.79 and 24.83 for 1, 2, and 8 Gy respectively). We observed that those "expected resistant patients" (DSB values lower than 1.78 DSB/Gy per 200 Mbp and RIA values over 9.58, 14.40 or 24.83 for 1, 2 and 8 Gy respectively) were at low risk of suffer severe subcutaneous late toxicity (HR 0.223, 95%CI 0.073-0.678, P = 0.008; HR 0.206, 95%CI 0.063-0.677, P = 0.009; HR 0.239, 95%CI 0.062-0.929, P = 0.039, for RIA at 1, 2 and 8 Gy respectively) in multivariate analysis.

Conclusions

A radiation-resistant profile is proposed, where those patients who presented lower levels of initial DNA damage and higher levels of radiation induced apoptosis were at low risk of suffer severe subcutaneous late toxicity after clinical treatment at high radiation doses in our series. However, due to the small sample size, other prospective studies with higher number of patients are needed to validate these results.

Radiation induced apoptosis and initial DNA damage are inversely related in locally advanced breast cancer patients

Background

DNA-damage assays, quantifying the initial number of DNA double-strand breaks induced by radiation, have been proposed as a predictive test for radiation-induced toxicity. Determination of radiation-induced apoptosis in peripheral blood lymphocytes by flow cytometry analysis has also been proposed as an approach for predicting normal tissue responses following radiotherapy. The aim of the present study was to explore the association between initial DNA damage, estimated by the number of double-strand breaks induced by a given radiation dose, and the radio-induced apoptosis rates observed.

Methods

Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radio-induced apoptosis at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide.

Results

Radiation-induced apoptosis increased in order to radiation dose and data fitted to a semi logarithmic mathematical model. A positive correlation was found among radio-induced apoptosis values at different radiation doses: 1, 2 and 8 Gy (p < 0.0001 in all cases). Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). A statistically significant inverse correlation was found between initial damage to DNA and radio-induced apoptosis at 1 Gy (p = 0.034). A trend toward 2 Gy (p = 0.057) and 8 Gy (p = 0.067) was observed after 24 hours of incubation.

Conclusions

An inverse association was observed for the first time between these variables, both considered as predictive factors to radiation toxicity.