Comparison between anterolateral thigh free flap and jejunal flap for tissue reconstruction in patients underwent resection of pharyngoesophageal squamous cell carcinoma after radiotherapy failure: a retrospective study

Background Anterolateral thigh (ALT) free flap and jejunal flap (JF) were commonly used in tissue reconstruction for pharyngoesophageal squamous cell carcinoma (PESCC) with worsening tissue adhesion and necrosis after radiotherapy failure. However, the results of tissue reconstruction and postoperative complications of these two flaps are controversial. The purpose of this study was to compare outcomes between group ALT free flap and group JF in PESCC after radiotherapy failure. Methods Intraoperative information and postoperative outcomes of patients with PESCC after radiotherapy failure who underwent ALT and JF reconstruction from January 2005 to December 2019 were compared and analyzed. Results The defect size of ALT (Numbers, 34) and JF (Numbers, 31) was 36.19 ± 11.35 cm2 and 35.58 ± 14.32 cm2 (p = 0.884), respectively. ALT and JF showed no significant difference in operation time (p = 0.683) and blood loss (p = 0.198). For postoperative outcomes within 30 days both in recipient site and donor site including wound bleeding, wound dehiscence, wound infection, and pharyngocutaneous fistula, ALT free flap and JF showed similar results. Flap compromise (Numbers, 2 VS.3, p = 0.663), flap take backs (Numbers, 1 VS.1, p = 1.000), partial flap failures (Numbers, 4 VS.2, p = 0.674), and total flap failures (Numbers, 0 VS.0, p = 1.000) showed no difference between the two groups. In addition, no significance was found in hypoproteinemia between the two groups (Numbers, 4 VS.2, p = 0.674). ALT free flap was not statistically different from JF in the incidence of dysphagia at the postoperative 6 months (Numbers of liquid diet, 5VS.5; Numbers of partial tube feeding, 6VS.7; Numbers of total tube feeding, 3VS.1, p = 0.790) and 12 months (Numbers of liquid diet, 8VS.7; Numbers of partial tube feeding, 8VS.7; Numbers of total tube feeding, 5VS.5, p = 0.998). The cause of dysphagia not found to differ between the two groups both in postoperative 6 months (p = 0.814) and 12 months (p = 0.845). Conclusion Compared with JF, ALT free flap for PESCC patients after radiotherapy failure showed similar results in postoperative outcomes. ALT free flap may serve as a safe and feasible alternative for PESCC patients after radiotherapy failure.

DNMT3A and DNMT3B Targeting as an Effective Radiosensitizing Strategy in Embryonal Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in childhood. Recently, we demonstrated the overexpression of both DNA methyltransferase 3A (DNMT3A) and 3B (DNMT3B) in RMS tumour biopsies and cell lines compared to normal skeletal muscle. Radiotherapy may often fail due to the abnormal expression of some molecules able to drive resistance mechanisms. The aim of this study was to analyse the involvement of DNMT3A and DNMT3B in radioresistance in RMS. RNA interference experiments against DNMT3A/3B were performed in embryonal RMS cells, upon ionizing radiation (IR) exposure and the effects of the combined treatment on RMS cells were analysed. DNMT3A and DNMT3B knocking down increased the sensitivity of RMS cells to IR, as indicated by the drastic decrease of colony formation ability. Interestingly, DNMT3A/3B act in two different ways: DNMT3A silencing triggers the cellular senescence program by up-regulating p16 and p21, whilst DNMT3B depletion induces significant DNA damage and impairs the DNA repair machinery (ATM, DNA-PKcs and Rad51 reduction). Our findings demonstrate for the first time that DNMT3A and DNMT3B overexpression may contribute to radiotherapy failure, and their inhibition might be a promising radiosensitizing strategy, mainly in the treatment of patients with metastatic or recurrent RMS tumours.

LncRNA H19 Upregulation Participates in the Response of Glioma Cells to Radiation

Previous studies have indicated that radiation resistance of glioma is one of the leading causes of radiotherapy failure. Mounting evidence suggests that long non-coding RNA (lncRNA) plays an important role in regulating radiosensitivity of cancer cells via implicating in various cell processes. However, the underlying mechanisms remain unclear and need further study, especially at the molecular level. We found that the expression level of lncRNA H19 was elevated by radiation, and then, the modulation of H19 affected the resistant of glioma cells to X-rays. Dual-luciferase reporter analyses showed that H19 was transcriptionally activated by CREB1 in glioma cells after irradiation. In addition, both flow cytometry and 5-ethynyl-2 ′ -deoxyuridine (EdU) assay suggested that H19 was involved in the cell cycle arrest, apoptosis, and DNA synthesis to modulate the radiation response of glioma cells and influenced their radioresistance. Therefore, H19 might play a crucial role in enhancing the radioresistance of glioma.

Feasibility and Clinical Value of CT-Guided 125I Brachytherapy for Pain Palliation in Patients With Breast Cancer and Bone Metastases After External Beam Radiotherapy Failure

Objectives: To evaluate the feasibility and clinical value of CT-guided iodine-125 (125I) brachytherapy for pain palliation in patients with breast cancer and bone metastases after external beam radiotherapy failure.Methods: From January 2014 to July 2016, a total of 90 patients, who had received the standard therapies for bone metastases but still suffered moderate-to-severe pain, were retrospectively studied. About 42 patients were treated with both 125I brachytherapy and bisphosphonates (Group A), and 48 patients were treated with bisphosphonates alone (Group B).Results: In Group A, 45 125I brachytherapy procedures were performed in 42 patients with 69 bone metastases; the primary success rate of 125I seed implantation was 92.9%, without severe complications. Regarding pain progression of the two groups, Group A exhibited significant relief in “worst pain,” “least pain,” “average pain,” and “present pain” 3-day after treatment and could achieve a 12-week-remission for “worst pain,” “least pain,” “average pain,” and “present pain.” The morphine-equivalent 24-h analgesic dose at 3 days, 4 weeks, 8 weeks, and 12 weeks was 91 ± 27, 53 ± 13, 31 ± 17, and 34 ± 12 mg for Group A, and 129 ± 21, 61 ± 16, 53 ± 15, and 105 ± 23 mg for Group B. Group A experienced a lower incidence of analgesic-related adverse events and better quality of life than Group B.Conclusion: The CT-guided 125I brachytherapy is a feasible and an effective treatment for the palliation of pain caused by bone metastases from breast cancer after external beam radiotherapy failure.

Detection of acquired radioresistance in breast cancer cell lines using Raman spectroscopy and machine learning

Radioresistance—a living cell’s response to, and development of resistance to ionising radiation—can lead to radiotherapy failure and/or tumour recurrence. We used Raman spectroscopy and machine learning to characterise biochemical changes...

Hypoxic Radioresistance: Can ROS Be the Key to Overcome It?

Radiotherapy is a mainstay treatment for many types of cancer and kills cancer cells via generation of reactive oxygen species (ROS). Incorporating radiation with pharmacological ROS inducers, therefore, has been widely investigated as an approach to enhance aerobic radiosensitization. However, this strategy was overlooked in hypoxic counterpart, one of the most important causes of radiotherapy failure, due to the notion that hypoxic cells are immune to ROS insults because of the shortage of ROS substrate oxygen. Paradoxically, evidence reveals that ROS are produced more in hypoxic than normoxic cells and serve as signaling molecules that render cells adaptive to hypoxia. As a result, hypoxic tumor cells heavily rely on antioxidant systems to sustain the ROS homeostasis. Thereby, they become sensitive to insults that impair the ROS detoxification network, which has been verified in diverse models with or without radiation. Of note, hypoxic radioresistance has been overviewed in different contexts. To the best of our knowledge, this review is the first to systemically summarize the interplay among radiation, hypoxia, and ROS, and to discuss whether perturbation of ROS homeostasis could provide a new avenue to tackle hypoxic radioresistance.

A review of pharyngeal mucosal closure technique in total laryngectomy

<p class="abstract"><strong>Background:</strong> The purpose of this retrospective analysis was to review our single institute based experience with the pharyngocutaneous fistula following total laryngectomy and to determine the impact of pharyngeal closure technique in the development of PCF in our patients.</p><p class="abstract"><strong>Methods:</strong> The medical records of the patients, who underwent total laryngectomy for squamous cell carcinoma of the larynx and hypopharynx in Government Royapettah Hospital, center for oncology between January 2010 and December 2017, were retrospectively reviewed. </p><p class="abstract"><strong>Results:</strong> 26 patients were included in the study of which 25 were male and 1 was female. Mean age of the patients were 58 years. Horizontal closure was done in 9 patients (35%) and T closure was done in 17 patients (65%). PCF was observed in 1 of 9 patients in horizontal closure. Remaining 17 patients underwent T closure of whom 8 patients developed PCF (p=0.06). Eight out of 18 patients (44%) developed PCF after salvage surgery after radiotherapy failure, Remaining 8 patients underwent primary laryngectomy for advanced stage cancers with cartilage involvement, of whom 1 patient developed PCF (12.5%) (p=0.11). In salvage laryngectomy (n=18), 1 of 6 cases developed PCF in horizontal closure and 7 of 12 cases in T closure technique (p=0.09).</p><p class="abstract"><strong>Conclusions:</strong> The incidence of fistula in our study was 34%. Horizontal closure was associated with decreased incidence of PCF when compared to ‘T’ closure of the defect. Prior radiotherapy had increased incidence of PCF.</p>