FOXC2-AS1 stabilizes FOXC2 mRNA via association with NSUN2 in gastric cancer cells.

Long noncoding RNA (lncRNA) FOXC2-AS1 has been reported to act as an oncogene in multiple human cancers. However, the clinical significance, functional role and underlying mechanism of FOXC2-AS1 in gastric cancer (GC) remains largely unknown. Here, we found that FOXC2-AS1 expression was significantly elevated in GC tissues and cells, and overexpression of FOXC2-AS1 indicated advanced TNM stage and shorter overall survival in GC patients. Functionally, knockdown of FOXC2-AS1 attenuated the proliferation, migration and invasion of GC cells, whereas overexpression of FOXC2-AS1 showed the opposite effects. Further investigation revealed that FOXC2-AS1 interacted with FOXC2 mRNA and repressed its degradation. FOXC2-AS1 recruited RNA methyltransferase NSUN2 to FOXC2 mRNA, increasing its m5C level and association with YBX1. Taken together, our findings suggested that FOXC2-AS1 acted as an oncogenic lncRNA by stabilizing FOXC2 mRNA in an m5C-dependent manner, which may provide a novel therapeutic target for GC.

Giant retroperitoneal paraganglioma: Challenges of misdiagnosis and high surgical risks, a case report.

INTRODUCTION AND IMPORTANCE: In surgery, misdiagnosis is not uncommon, usually a result of erroneous image interpretations and pathology diagnosis especially involving a tumor or cancer. Misdiagnosis may cause increased morbidity, mortality and surgical risks. CASE PRESENTATION: A 49-year-old man presented for the second time with a right upper abdominal mass of 7 months. Previous CT scan of abdomen and exploratory surgery made the diagnosis of liver cancer. Two other tertiary hospitals drew the similar conclusions. At a cancer hospital the needle biopsy was suspicious for gastrointestinal stromal tumor, Imatinib was recommended but not started due to high cost. During this re-admission, the diagnosis of liver cancer or GIST was challenged. A high risk surgery was done with successive removal of a giant tumor. A final diagnosis of paraganlioma was made and the patient is now tumor free for 6 years. CLINICAL DISCUSSION: There are 4 lessons from this case. First, a paraganlioma may be misdiagnosed. Second, the misdiagnosis may be misled by CT scan and pathology. Third, a misdiagnosis can cause increased morbidity, mortality and surgical risks. Forth, massive intraoperative hemorrhage is a high risk of surgery. CONCLUSION: Careful clinical evaluation combined with pathology diagnosis may reduce the misdiagnosis of some tumor/cancer. Surgical resection may be the only way to reach a diagnosis in patient with paraganlioma. Massive intraoperative hemorrhage is a high risk of surgery in such patients.

Cell-free DNA as a liquid biopsy for early detection of gastric cancer.

Gastric cancer (GC) is one of the most common malignant tumors with poor prognosis worldwide, mainly due to the lack of suitable modalities for population-based screening and early detection of this disease. Therefore, novel and less invasive tests with improved clinical utility are urgently required. The remarkable advances in genomics and proteomics, along with emerging new technologies for highly sensitive detection of genetic alterations, have shown the potential to map the genomic makeup of a tumor in liquid biopsies, in order to assist with early detection and clinical management. The present review summarize the current status in the identification and development of cell-free DNA (cfDNA)-based biomarkers in GC, and also discusses their potential utility and the technical challenges in developing practical cfDNA-based liquid biopsy for early detection of GC.

The challenges of urgent radical sigmoid colorectal cancer resection in a COVID-19 patient: A case report.

INTRODUCTION: The COVID-19 pandemic presents a unique global health challenge further complicating surgical management of COVID-19 positive patients due to a lack of published literature. CASE: Within we discuss a 48-year-old Chinese man, presenting with acute gastrointestinal obstruction due to sigmoid colonic mass. The patient was screened and tested positive for COVID 19 due to his employment in Wuhan, China at the COVID-19 pandemic epicenter. The patient was subsequently taken for open sigmoid colonic resection, however the case presented multiple challenges due to the patient's COVID-19 positive status. DISCUSSION: The challenges of surgical management of COVID-19 positive patients exist are four-fold. First the unknown efficacy of pre-surgical risk stratification in COVID-19 positive patients, second the risk of aerosolized COVID-19 transmission during intubation for surgery, third the risk of fecal COVID-19 transmission to surgical staff during large bowel resection, and fourth the post-operative challenges of caring for COVID-19 positive patients. CONCLUSION: Further research is needed into these topics, as well as the medical management of COVID-19 surgical patients.

LncRNA LINC00470 promotes proliferation through association with NF45/NF90 complex in hepatocellular carcinoma.

Increasing evidence demonstrates that long noncoding RNAs (lncRNAs) play an important role in the development and progression of human cancers. LncRNA LINC00470 has been reported to function as an oncogene in glioblastoma. Until now, the roles and underlying mechanisms of LINC00470 in the progression of hepatocellular carcinoma (HCC) remain unclear. Here, we found that LINC00470 was upregulated in HCC cells and tissues. High-level LINC00470 was significantly correlated with bigger tumor size, advanced TNM stage and poor prognosis in patients with HCC. Functional studies showed that knockdown of LINC00470 expression inhibited HCC cell proliferation and cell cycle progression, while overexpression of LINC00470 showed the opposite effects. Further investigation suggested that LINC00470 was associated with NF45/NF90 complex and increased its interaction with cyclin E1 mRNA, thus inhibiting the degradation of cyclin E1 mRNA. Additionally, knockdown of cyclin E1 in LINC00470-overexpressed cells abolished its promotive effects on HCC cell proliferation. In summary, our findings suggest that targeting LINC00470 could be a potential therapeutic approach in treating HCC patients.

LncRNA LINC00470 promotes the degradation of PTEN mRNA to facilitate malignant behavior in gastric cancer cells.

Gastric cancer (GC) is the fourth most frequent malignancy worldwide. Recently, long noncoding RNA (lncRNA) LINC00470 has been demonstrated to play an oncogenic role in human cancer. However, the clinical significance and functional role of LINC00470 in the progression of GC is largely unknown. In this study, our findings showed that LINC00470 was significantly upregulated in GC tissues and cell lines, and correlated with distant metastasis, TNM stage and poor prognosis. Overexpression and knockdown experiments revealed its oncogenic functions on GC cell proliferation, migration and invasion. Mechanistically, LINC00470 associated with PTEN mRNA and suppressed its stability through interaction with the N6-methyladenosine (m6A) writer METTL3. We also showed that LINC00470-METTL3-mediated PTEN mRNA degradation relied on the m6A reader protein YTHDF2-dependent pathway. Taken together, LINC00470 might serve as a therapeutic target for GC patients.