A rare case of persistent postendodontic symptomatic maxillary central incisor with aberrant canal configuration confirmed by cone-beam computer tomography and its nonsurgical management by retreatment.

Maxillary central incisor is considered the tooth with least anatomical variations. In literature, the prevalence of single root and single canal in maxillary central incisor has been reported as 100%. Only a handful of case reports suggesting more than one root or one canal are available and are mostly associated with developmental anomalies such as gemination and fusion. This article describes a rare case report of retreatment of a maxillary central incisor with two roots with normal clinical crown which was confirmed by cone-beam computer tomography (CBCT). A 50-year-old Indian male patient presented with pain and discomfort on a root canal-treated anterior tooth. Pulp sensibility testing of left maxillary central incisor was negative. Intraoral periapical digital radiograph revealed an obturated canal with suspected outline of a second root which got confirmed with cone shift technique. The tooth was treated under dental operating microscope during which two canals were located and retreatment was completed. Postobturation, CBCT was performed to study the root and canal morphology. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth without any active periapical lesion. The present case report emphasizes the fact that clinicians should approach each case with an open mind having a thorough knowledge of the normal tooth anatomy and should suspect variations in every case to ensure successful endodontic outcome.

Long non-coding RNA LSAMP-1 is down-regulated in non-small cell lung cancer and predicts a poor prognosis.

BACKGROUND: Long noncoding RNAs (lncRNAs) are emerging as master regulators for gene expression and thus play a vital role in human tumorigenesis and progression. But the involvement of novel lncRNAs in non-small cell lung cancer (NSCLC) remains largely unelucidated. METHODS: A total of 170 NSCLC and their adjacent non-tumor tissues were enrolled to detect the expression of Lnc-LSAMP-1 by RT-qPCR. The effects of Lnc-LSAMP-1 on cell proliferation, migration, invasion and drug-sensitivity were determined by in vitro and in vivo experiments. The proteins that interact with Lnc-LSAMP-1were confirmed by RNA pull-down assay. RNA-sequencing were used to identify the potential targets of Lnc-LSAMP-1 in NSCLC. RESULTS: We found that Lnc-LSAMP-1 was significantly down-regulated in 170 cases of NSCLC tissues when compared to their adjacent non-cancerous tissues. Loss expression of Lnc-LSAMP-1 was notably correlated with unfavorable prognosis of NSCLC patients. The ectopic expression of Lnc-LSAMP-1 drastically inhibited lung cancer cell proliferation, viability, invasion and migration ability, arrested cell cycle and facilitated apoptosis. Chemotherapy sensitization experiments showed that over-expressed Lnc-LSAMP-1 enhanced the inhibition of cell proliferation induced by TKI. Mechanistically, Lnc-LSAMP-1-LSAMP formed a complex which could protect the degradation of LSAMP gene, and thus exerted crucial roles in NSCLC progression and TKI targeted treatment. CONCLUSIONS: Consequently, our findings highlight the function and prognostic value of Lnc-LSAMP-1 in NSCLC and provide potential novel therapeutic targets and prognostic biomarkers for patients with NSCLC.

Erratum to upregulation of long noncoding RNA RAB11B-AS1 promotes tumor metastasis and predicts poor prognosis in lung cancer.

[This corrects the article DOI: 10.21037/atm.2020.04.52.].

Upregulation of long noncoding RNA RAB11B-AS1 promotes tumor metastasis and predicts poor prognosis in lung cancer.

BACKGROUND: Lung cancer (LC) is one of the leading causes of cancer-related mortality in China and worldwide. Despite the progress in diagnosis and treatment of LC, the prognosis of LC remains poor. Studies have demonstrated that long non-coding RNAs (lncRNAs) play a critical role in carcinogenesis and cancer development. METHODS: Here we examined the expression and potential function of lnc-RAB11B-AS1 in LC both in vitro and in vivo. All experiments in this study were conducted using A549 and PC-9 cell lines according to protocols described in this paper. The clinic characteristics were analyzed using logistic regression, cox model, log rank test, biochemical analysis using qRT-PCR, transfections, nude mice model, and cell biological analysis using Transwell assay, CCK-8 assay, flow cytometry, and rescue experiments, and immunohistochemistry. RESULTS: The results showed that lnc-RAB11B-AS1 was significantly overexpressed in LC tissues compared to the corresponding non-tumor tissues. Patients with a higher level of lnc-RAB11B-AS1 expression showed a poorer overall survival rate. Functionally, overexpression of lnc-RAB11B-AS1 promotes cell proliferation, migration and invasion abilities of LC cell lines, which suggests lnc-RAB11B-AS1 may play an oncogenic role in LC. lnc-RAB11B-AS1 was located in physical contiguity with RAB11B gene and found positively regulates the RAB11B expression, and the protein levels of RAB11B in LC tissues also found to positively correlated with the level of lnc-RAB11B-AS1 expression. RAB11B silencing partially abrogated lnc-RAB11B-AS1-induced proliferation of the LC cell lines used in this study. CONCLUSIONS: This study provided a novel evidence into the function of lncRNA-driven carcinogenesis. Our findings highlighted the importance of lnc-RAB11B-AS1 and RAB11B in LC progression and indicated that lnc-RAB11B-AS1 may serve as a novel and valuable prognostic biomarker for LC.

Long Noncoding RNA PRRG4-4 Promotes Viability, Cell Cycle, Migration, and Invasion in Lung Cancer Cells.

There is a perception that long noncoding RNA (lncRNA) has relationship with carcinogenesis. Many studies have previously identified and validated that the section of chromosome 11p13 is associated with high incidence of tumor. In this study, we investigated a new lncRNA, named lncPRRG4-4, mapped to 11p13 and suspected that lncPRRG4-4 was a potential lung cancer-related gene. To explore its role in carcinogenesis, we first demonstrated that lncPRRG4-4 was upregulated in lung cancer tissues compared with adjacent nontumor tissues and functioned as an oncogene in lung cancer cells. The lncPRRG4-4 was significantly upregulated in lung cancer tissues compared with adjacent normal counterparts (mean ± standard deviation: 0.12 ± 0.84 vs. 0.05 ± 0.22; p < 0.001). Patients with metastasis exhibited high levels of lncPRRG4-4 expression than those without metastasis in both the southern samples (p = 0.045) and eastern samples (p = 0.030), total samples (p = 0.004). In addition, downregulation of lncPRRG4-4 expression inhibited lung cancer proliferation, viability, migration, and invasion ability, arrested cell cycle, facilitated apoptosis, and vice versa. Taken together, these observations suggested that the lncPRRG4-4 functions as an oncogene in lung cancer cells.

Upregulation of LncRNA FEZF-AS1 is associated with advanced clinical stages and family history of cancer in patients with NSCLC.

Antisense RNA (AS) is a type of long non-coding RNAs that functions as a post-transcriptional regulatory element on regulating parental coding gene expression via directly binding to complementary mRNA sequences. We aimed to investigate the effect of the AS to FEZF1 gene on non-small cell lung cancer (NSCLC) development. The expression level of lncRNA FEZF-AS1 and FEZF1 was determined by the quantitative Real-time PCR in 160 cases of NSCLC tissues and their adjacent non-tumour tissues. We found that lncRNA FEZF-AS1 was significantly up-regulated in tumour tissues when compared to the adjacent non-cancerous tissues (P = 0.001), and it's high expression correlated with advanced stages (P = 0.002) and Tumour Family History (P = 0.029). Meanwhile, In 58 cases of NSCLC tissues the expression of lncRNA FEZF-AS1 was positively associated with that of FEZF1expression (r = 0.8810, p = 1.6575E-20). By GEPIA database analysis, we also found that the expression of lncRNA FEZF-AS1 and FEZF1 were significantly higher in tumour tissues than those of the adjacent non-cancerous tissues in 969 NSCLC patients (P < 0.05), and lncRNA FEZF-AS1 was positively correlated with FEZF1 (r = 0.90, P < 0.001). These results suggest that lncRNA FEZF-AS1 relate to the progression of lung cancer patients and it may be a potential target for cancer therapy.