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Pancreatic ductal adenocarcinoma (PDAC) is seriously resistant to radiotherapy and the mechanism is largely unknown. HOX transcript antisense intergenic RNA (HOTAIR) is overexpressed in PDAC. However, the function of HOTAIR has never been related to the radiosensitivity of PDAC. In this present study, the expression of HOTAIR in the PDAC cell lines and tissues was measured by quantitative real-time PCR (qRT-PCR), and the association between HOTAIR expression levels and X-ray treatment in PDAC cell lines was investigated. Additionally, the influence of HOTAIR knockdown on radiosensitivity, proliferation, and apoptosis of PDAC cells after radiation was evaluated by colony formation assays, Cell Counting Kit-8 (CCK-8) assays, and flow cytometry, respectively. Furthermore, the correlation between HOTAIR and Wnt inhibitory factor 1 (WIF-1) expression in PDAC cell lines and tissues was studied to assess the role of HOTAIR and WIF-1 in the radiosensitivity of PDAC. The results confirmed that HOTAIR expression was significantly increased in the PDAC cell lines and tissues ( n = 90) compared with human normal pancreatic ductal epithelial cell line (HPDE) and matched adjacent normal tissues ( n = 90). Functionally, HOTAIR knockdown enhanced the radiosensitivity of PDAC cells, reduced the proliferation, and increased the apoptosis of cells after radiation. And HOTAIR silencing increased the expression of WIF-1. Furthermore, the overexpression of WIF-1 revealed that HOTAIR modulated the radiosensitivity of PDAC cells by regulating the expression of WIF-1. These data reveals that HOTAIR can affect the radiosensitivity of PDAC cells partly via regulating the expression of WIF-1, and HOTAIR-WIF-1 axis is a potential target for PDAC radiotherapy. [ABSTRACT FROM AUTHOR]

Aberrant activation of NFκB orchestrates a critical role in tumor carcinogenesis; however, the regulatory mechanisms underlying this activation are not fully understood. Here we report that a novel long noncoding RNA (lncRNA) Uc003xsl.1 is highly expressed in triple-negative breast cancer (TNBC) and correlates with poor outcomes in patients with TNBC. Uc003xsl.1 directly bound nuclear transcriptional factor NFκB-repressing factor (NKRF), subsequently preventing NKRF from binding to a specific negative regulatory element in the promoter of the NFκB-responsive gene IL8 and abolishing the negative regulation of NKRF on NFκB-mediated transcription of IL8. Activation of the NFκB/IL8 axis promoted the progression of TNBC. Trop2-based antibody-drug conjugates have been applied in clinical trials in TNBC. In this study, a Trop2-targeting, redox-responsive nanoparticle was developed to systematically deliver Uc003xsl.1 siRNA to TNBC cells in vivo, which reduced Uc003xsl.1 expression and suppressed TNBC tumor growth and metastasis. Therefore, targeting Uc003xsl.1 to suppress the NFκB/IL8 axis represents a promising therapeutic strategy for TNBC treatment., Significance: These findings identify an epigenetic-driven NFκB/IL8 cascade initiated by a lncRNA, whose aberrant activation contributes to tumor metastasis and poor survival in patients with triple-negative breast cancer., (©2021 The Authors; Published by the American Association for Cancer Research.)

Resistance to radiotherapy is frequently encountered in clinic, leading to poor prognosis of cancer patients. Long noncoding RNAs (lncRNAs) play important roles in the development of radioresistance due to their functions in regulating the expression of target genes at both transcriptional and posttranscriptional levels. Exploring key lncRNAs and elucidating the mechanisms contributing to radioresistance are crucial for the development of effective strategies to reverse radioresistance, which however remains challenging. Here, actin filament-associated protein 1 antisense RNA1 (lncAFAP1-AS1) is identified as a key factor in inducing radioresistance of triple-negative breast cancer (TNBC) via activating the Wnt/ β -catenin signaling pathway. Considering the generation of a high concentration of reduction agent glutathione (GSH) under radiation, a reduction-responsive nanoparticle (NP) platform is engineered for effective lncAFAP1-AS1 siRNA (siAFAP1-AS1) delivery. Systemic delivery of siAFAP1-AS1 with the reduction-responsive NPs can synergistically reverse radioresistance by silencing lncAFAP1-AS1 expression and scavenging intracellular GSH, leading to a dramatically enhanced radiotherapy effect in both xenograft and metastatic TNBC tumor models. The findings indicate that lncAFAP1-AS1 can be used to predict the outcome of TNBC radiotherapy and combination of systemic siAFAP1-AS1 delivery with radiotherapy can be applied for the treatment of recurrent TNBC patients., Competing Interests: The authors declare no conflict of interest., (© 2020 The Authors. Published by Wiley‐VCH GmbH.)

Pancreatic ductal adenocarcinoma (PDAC) is seriously resistant to radiotherapy and the mechanism is largely unknown. HOX transcript antisense intergenic RNA (HOTAIR) is overexpressed in PDAC. However, the function of HOTAIR has never been related to the radiosensitivity of PDAC. In this present study, the expression of HOTAIR in the PDAC cell lines and tissues was measured by quantitative real-time PCR (qRT-PCR), and the association between HOTAIR expression levels and X-ray treatment in PDAC cell lines was investigated. Additionally, the influence of HOTAIR knockdown on radiosensitivity, proliferation, and apoptosis of PDAC cells after radiation was evaluated by colony formation assays, Cell Counting Kit-8 (CCK-8) assays, and flow cytometry, respectively. Furthermore, the correlation between HOTAIR and Wnt inhibitory factor 1 (WIF-1) expression in PDAC cell lines and tissues was studied to assess the role of HOTAIR and WIF-1 in the radiosensitivity of PDAC. The results confirmed that HOTAIR expression was significantly increased in the PDAC cell lines and tissues (n = 90) compared with human normal pancreatic ductal epithelial cell line (HPDE) and matched adjacent normal tissues (n = 90). Functionally, HOTAIR knockdown enhanced the radiosensitivity of PDAC cells, reduced the proliferation, and increased the apoptosis of cells after radiation. And HOTAIR silencing increased the expression of WIF-1. Furthermore, the overexpression of WIF-1 revealed that HOTAIR modulated the radiosensitivity of PDAC cells by regulating the expression of WIF-1. These data reveals that HOTAIR can affect the radiosensitivity of PDAC cells partly via regulating the expression of WIF-1, and HOTAIR-WIF-1 axis is a potential target for PDAC radiotherapy.

Objective: To investigate the feasibility of Xelox(capecitabine plus oxaliplatin) in the volumetric modulated arc therapy(VMAT)-based preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer(LARC)., Methods: Clinical data of 141 LARC patients in our hospital from April 2011 to April 2013 treated by preoperative CRT based on VMAT with concurrent Xelox followed by surgery were analyzed retrospectively. There were 95 men and 46 women, and the median age was 56 years old. Clinical staging was stage II( in 33 cases(18 cases with II(a, 11 cases with II(b, 4 cases with II(c) and stage III( in 108 cases(1 case with III(a, 52 cases with III(b, 55 cases with III(c). The target doses were 50 Gy for PTV1 in 25 fractions and 46 Gy for PTV2 in 23 fractions., Results: All the patients completed the planned radiotherapy, and only 2 cases were interrupted with acute grade 3 diarrhea. The overall incidence of grade 3 hematologic and non-hematologic adverse events during CRT was 9.9% and 16.3% respectively without grade 4 toxicity. Operation was performed after a median interval of 54 days(34-86 days) following CRT. The R0 resection rate was 100%, sphincter preservation rate for low rectal cancer was 45.8%(33/72), postoperative complication morbidity was 17.0%(24/141), pCR rate was 32.6%(46/141), and rates of pathological down-staging for the primary tumor, lymph node and clinical stage were 87.2%, 88% and 90.1%, respectively., Conclusions: Xelox is feasible and well tolerated in the treatment of VMAT-based preoperative CRT for patients with LARC, with excellent rates of pCR and pathological down-staging.