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Carbon-ion radiotherapy (CIRT) enhanced local control in patients with malignant melanoma. In several in vitro studies, carbon ions (C ions) have been also shown to decrease the metastatic potential of melanoma cells. CXC motif 10 (CXCL10) has been shown to play a crucial role in regulating tumor metastasis and it significantly increase in human embryonic kidney cells after heavy ion irradiations. This study sought to explore the regulatory effect of C ions on melanoma metastasis, emphasizing the role of CXCL10 in this process. To explore the potential regulatory effect of C ions on tumor metastasis in vivo, we developed a lung metastasis mouse model by injecting B16F10 cells into the footpad and subjected all mice to treatment with X rays and C ions. Subsequently, a series of assays, including histopathological analysis, enzyme-linked immunosorbent assay, real-time PCR, and western blotting, were conducted to assess the regulatory effects of C ions on melanoma. Our results showed that mice treated with C ions exhibited significantly less tumor vascularity, enhanced tumor necrosis, alleviated lung metastasis, and experienced longer survival than X-ray irradiated mice. Moreover, VEGF expression in B16F10 cells was significantly reduced by C-ion treatment, which could be alleviated by CXCL10 knockdown in vitro. Further investigations revealed that co-culturing with HUVECs resulted in a significant inhibition of proliferation, migration, and tube formation ability in the C-ion treated group, while the opposite effect was observed in the C-ion treated with si-CXCL10 group. In conclusion, our findings demonstrate that treatment with carbon-ion radiation can suppress angiogenesis and lung metastases in melanoma by specifically targeting CXCL10. These results suggest the potential utility of carbon ions in treating melanoma. [ABSTRACT FROM AUTHOR]

Objective: Carbon ions suppress the effect of glutathione peroxidase 4 (GPX4) on the proliferation and metastasis of lung adenocarcinoma A549 cells. Methods: The clonogenic formation ability of A549 cells was calculated with different ray doses of radiation. Cell proliferation, cycle, and apoptosis of A549 cells after different ray irradiation were detected by cck8 and flow cytometry. The transwell assay was used to detect the cell migration and invasion after different rays of radiation to A549 cells. The GPX4 matrix metalloproteinase 2 and E‐cadherin expression levels were assessed by immunofluorescence and western blot. Results: At the dose of 4 Gy, A549 cell viability was 22.95 ± 5.00% and 55.52 ± 3.26% when treated with carbon ions and X‐rays, respectively. The distribution of A549 cells arrested in the G2 phase by carbon ion irradiation was positively correlated with radiation dose, with a most significant increase at 4 Gy irradiation (t = 4.303, p < 0.05). The results of apoptosis after irradiation showed were no significant differences in apoptosis at 1 and 2 Gy of X‐ray compared with 0 Gy, and 4 Gy irradiation significantly induced apoptosis in A549 cells (t = 30.520, p < 0.05). The apoptotic rate of carbon ion‐irradiated cells increased in a dose‐dependent manner and was the highest at 4 Gy (t = 17.356, p < 0.05). The transwell assays showed significantly decreased migration and invasion of both ray‐irradiated cells compared with the 0 Gy control cells. The carbon ions of 2 and 4 Gy significantly inhibited A549 cell migration (t2Gy = 9.260, t4Gy = 19.052, both p < 0.05) and invasion compared with those in the control cells (t2Gy = 6.141, t4Gy = 12.700, both p < 0.05). Treatment with 2 and/or 4 Gy doses of carbon ion reduced GPX4 (t2Gy = 8.170, t4Gy = 13.811, both p < 0.05) and matrix metalloproteinase 2 (t2Gy = 207.620, t4Gy = 93.170, both p < 0.05) protein expression, but E‐cadherin expression was increased (t2Gy = 62.811, t4Gy = 102.106, both p < 0.05). Conclusion: Compared with X‐ray irradiation, carbon ions have a higher relative biological effectiveness and can increase the proportion of A549 cells arrested in the G2/M stage to induce apoptosis, thereby inhibiting proliferation. At the same dose with X‐ray, carbon ions may inhibit the migration and invasion of A549 cells by regulating the expression of GPX4, matrix metalloproteinase 2, and E‐cadherin. [ABSTRACT FROM AUTHOR]

Pelvic radiotherapy is the key treatment for pelvic malignancies, usually including pelvic primary tumour lesions and lymphatic drainage areas in the pelvic region. Therefore, the intestinal tract in the radiation field is inevitably damaged, a phenomenon clinically referred to as radiation enteritis, and diarrhoea is the most common clinical symptom of radiation enteritis. Therefore, it is necessary to study the mechanism of radiation-induced diarrhoea. It has been found that the gut microbiome plays an important role in the development of diarrhoea in response to pelvic radiotherapy, and the species and distribution of intestinal microbiota are significantly altered in patients after pelvic radiotherapy. In this study, we searched for articles indexed in the Cochrane Library, Web of Science, EMBASE and PubMed databases in English and CNKI, Wanfang data and SINOMED in Chinese from their inception dates through 13 March 2020 to collect studies on the gut microbiome in pelvic radiotherapy patients. Eventually, we included eight studies: one study report on prostatic carcinoma, five studies on gynaecological carcinoma and two papers on pelvic carcinomas. All studies were designed as self-controlled studies, except for one that compared toxicity to nontoxicity. The results from all the studies showed that the diversity of intestinal flora decreased during and after pelvic radiotherapy, and the diversity of intestinal flora decreased significantly in patients with diarrhoea after radiotherapy. Five studies observed that the community composition of the gut microbiota changed at the phylum, order or genus level before, during, and after pelvic radiotherapy at different time points. In addition, the composition of the gut microbiota before radiotherapy was different between patients with postradiotherapy diarrhoea and those without diarrhoea in five studies. However, relevant studies have not reached consistent results regarding the changes in microbiota composition. Changes in the intestinal flora induced by pelvic radiotherapy and their relationship between changes in intestinal flora and the occurrence of radiation-induced diarrhoea (RID) are discussed in this study, providing a theoretical basis for the causes of RID after pelvic radiotherapy. [ABSTRACT FROM AUTHOR]

Background: A combination of programmed cell death protein‐1 (PD‐1)/programmed cell death ligand‐1 (PD‐L1) inhibitors and radiotherapy (RT) is increasingly being used to treat non‐small‐cell lung cancer (NSCLC). However, the safety and efficacy of this approach remains controversial. We performed a systematic review and meta‐analysis to summarize the related research. Methods: We searched the China Biology Medicine, EMBASE, Cochrane Library, and PubMed databases for all the relevant studies. The Stata software, version 12.0 was used for the meta‐analysis. Results: The study included 20 clinical trials that enrolled 2027 patients with NSCLC. Compared with non‐combination therapy, combination therapy using PD‐1/PD‐L1 inhibitors and RT was associated with prolonged overall survival (OS) (1‐year OS: odds ratio [OR] 1.77, 95% confidence interval [CI] 1.35–2.33, p = 0.000; 2‐year OS: OR 1.77, 95% CI 1.35–2.33, p = 0.000) and progression‐free survival (PFS) (0.5‐year PFS: OR 1.83, 95% CI 1.13–2.98, p = 0.014; 1‐year PFS: OR 2.09, 95% CI 1.29–3.38, p = 0.003; 2‐year PFS: OR 2.47, 95% CI 1.13–5.37, p = 0.023). Combination therapy also improved the objective response rate (OR 2.76, 95% CI 1.06–7.19, p = 0.038) and disease control rate (OR 1.80, 95% CI 1.21–2.68, p = 0.004). This meta‐analysis showed that compared with non‐combination therapy, combination therapy using PD‐1/PD‐L1 inhibitors and RT did not increase the serious adverse event rates (≥grade 3); however, this approach increased the rate of grade 1–2 immune‐related or radiation pneumonitis. Subgroup analyses revealed that the sequence of PD‐1/PD‐L1 inhibitors followed RT outperformed in which concurrent PD‐1/PD‐L1 inhibitor and RT followed PD‐1/PD‐L1 inhibitor. Combination of stereotactic body RT or stereotactic radiosurgery with PD‐1/PD‐L1 inhibitors may be more effective than a combination of conventional RT with PD‐1/PD‐L1 inhibitors in patients with advanced NSCLC. Conclusion: Combination therapy using PD‐1/PD‐L1 inhibitors and RT may improve OS, PFS, and tumor response rates without an increase in serious adverse events in patients with advanced NSCLC. However, combination therapy was shown to increase the incidence of mild pneumonitis. [ABSTRACT FROM AUTHOR]

Malignant melanomas (MMs) were the fifth most common cancer in men and the sixth most common cancer in women in 2018, respectively. These are characterized by high metastatic rates and poor prognoses. We systematically reviewed safety and efficacy of carbon‐ion radiotherapy (CIRT) for treating MMs. Eleven studies were eligible for review, and the data showed that MM patients showed better local control with low recurrence and mild toxicities after CIRT. Survival rates were slightly higher in patients with cutaneous or uveal MMs than in those with mucosal MMs. CIRT in combination with chemotherapy produced higher progression‐free survival rates than CIRT only. In younger patients, higher rates of distant metastases of gynecological MMs were observed. The data indicated that CIRT is effective and safe for treating MMs; however, a combination with systemic therapy is recommended to ensure the best possible prognosis for MMs. [ABSTRACT FROM AUTHOR]

Background: Controversy persists about whether additional induction chemotherapy (ICT) before neoadjuvant chemoradiation (NCRT) yields improved oncological outcomes. We performed a systematic review and meta-analysis to compare ICT+ NCRT+ surgery(S) with NCRT+ S in patients with locally advanced rectal cancer (LARC). Methods: We searched the PubMed, EMBASE, Cochrane Library, and China Biology Medicine (CBM) databases. The data were analyzed with Stata version 12.0 software. Results: We identified 9 relevant trials that enrolled 1538 patients. We detected no significant difference in the 5-year overall survival (OS) (OR 1.50, 95% CI 0.48–4.64), disease-free survival (DFS) (OR 1.03, 95% CI 0.73–1.46), local recurrence (LR) (OR 0.80, 95% CI 0.45–1.43), and distant metastasis (DM) rates (OR 1.03, 95% CI 0.55–1.93) between patients who did and did not receive ICT. The addition of ICT before NCRT had a similar pathological complete response rate compared to NCRT (OR 1.26, 95% CI 0.90–1.77). Our findings suggest that between the ICT + NCRT+S and NCRT+S groups, ICT improved the incidence of grade 3 to 4 toxicity effects (OR 4.81, 95% CI 2.38–9.37), but between the ICT + NCRT+S and NCRT+S+ adjuvant chemotherapy (ACT) groups, ICT might reduce toxicity (OR 0.19, 95% CI 0.08–0.50). ICT had no significant impact on surgical complications (OR 0.97, 95% CI 0.63–1.51). Conclusions: The addition of ICT before NCRT seemingly shows no survival benefit on patients with LARC, and might increase the toxicity. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the various effects of high linear energy transfer (LET) carbon ion (12C6+) and low LET X-ray radiation on MDA-MB-231 and MCF-7 human breast cancer cells and to explore the underlying mechanisms of radiation sensitivity. Cell proliferation, cell colony formation, cell cycle distribution, cell apoptosis and protein expression levels [double-strand break marker γ-H2AX, cell cycle-related protein cyclin B1, apoptosis-related proteins Bax and Bcl-2, and the Akt/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase B1 (p70S6K) pathway] were detected after irradiation with carbon ions or X-rays at doses of 0, 2, 4 and 8 Gy. Our results showed that the inhibition of cell proliferation and cell colony formation and the induction of G2/M phase arrest, DNA lesions and cell apoptosis/necrosis elicited by carbon ion irradiation were more potent than the effects elicited by X-ray radiation at the same dose. Simultaneously, compared with X-ray radiation, carbon ion radiation induced a marked increase in Bax and prominent decreases in cyclin B1 and Bcl-2 in a dose-dependent manner. Furthermore, the Akt/mTOR/p70S6K pathway was significantly inhibited by carbon ion radiation in both breast cancer cell lines. These results indicate that carbon ion radiation kills MDA-MB-231 and MCF-7 breast cancer cells more effectively than X-ray radiation, which might result from the inhibition of the Akt/mTOR/p70S6K pathway. [ABSTRACT FROM AUTHOR]

Background: Radiation is a mode of treatment for many pelvic malignancies, most of which originate in the gynecologic, gastrointestinal, and genitourinary systems. However, the healthy gut is unavoidably included in the irradiation volume, resulting in undesirable results that manifest as radiation-induced diarrhea (RID), which is the most common side effect of radiation therapy and significantly affects the patients' quality of life. This study aimed to investigate the potential mechanism of diarrhea after pelvic radiotherapy in rats based on the effect of radiation on bile acid homeostasis and sodium-dependent bile acid transporter (Asbt). Methods: In this experimental study, male Sprague-Dawley rats were divided into the following groups – pelvic irradiation, cholestyramine-concurrent radiation, and control groups. The rats in the pelvic irradiation group were irradiated in the pelvic region with 2 Gy per day for five consecutive days. The total bile acid (TBA) levels in the ileum, colon, and feces were measured using automatic biochemical analyzer, and the levels of individual bile acids were evaluated by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The mRNA and protein expression of Asbt in ileum were assessed by qRT-PCR and Western blot assay. The rats in the cholestyramine-concurrent radiation group were administered with cholestyramine, a bile acid-chelating resin, and concurrent radiation for 5 days. The body weight of rats was monitored daily, and the degree of diarrhea was scored. Results: Diarrhea was observed at 2 and 3 days post-pelvic radiation. The TBA levels were significantly decreased at 4 and 5 days post-radiation in the ileum (p <.01, p <.01) and increased at 4 and 5 days post-radiation in the colon (p <.05, p <.05). The fecal excretions of TBA were significantly increased at 3, 4, and 5 days post-radiation (p <.05). The levels of individual bile acids were significantly decreased in the ileum and increased in the colon and feces, post-radiation. The mRNA and protein expression of Asbt in the ileum gradually decreased with increasing days of pelvic radiation and significantly decreased at 3 and 5 days post-radiation, respectively. Furthermore, a significant decrease in body weight was observed post-pelvic radiation, and cholestyramine administration did not reverse the weight loss. However, the incidence of RID was decreased after administration of cholestyramine. Conclusions: Bile acid malabsorption is partially responsible for RID post-pelvic radiation in rats, and the potential mechanism is related to the downregulation of the ileal Asbt. [ABSTRACT FROM AUTHOR]