FBXO32-mediated degradation of PTEN promotes lung adenocarcinoma progression.

FBXO32, a member of the F-box protein family, is known to play both oncogenic and tumor-suppressive roles in different cancers. However, the functions and the molecular mechanisms regulated by FBXO32 in lung adenocarcinoma (LUAD) remain unclear. Here, we report that FBXO32 is overexpressed in LUAD compared with normal lung tissues, and high expression of FBXO32 correlates with poor prognosis in LUAD patients. Firstly, we observed with a series of functional experiments that FBXO32 alters the cell cycle and promotes the invasion and metastasis of LUAD cells. We further corroborate our findings using in vivo mouse models of metastasis and confirmed that FBXO32 positively regulates LUAD tumor metastasis. Using a proteomic-based approach combined with computational analyses, we found a positive correlation between FBXO32 and the PI3K/AKT/mTOR pathway, and identified PTEN as a FBXO32 interactor. More important, FBXO32 binds PTEN via its C-terminal substrate binding domain and we also validated PTEN as a bona fide FBXO32 substrate. Finally, we demonstrated that FBXO32 promotes EMT and regulates the cell cycle by targeting PTEN for proteasomal-dependent degradation. In summary, our study highlights the role of FBXO32 in promoting the PI3K/AKT/mTOR pathway via PTEN degradation, thereby fostering lung adenocarcinoma progression.

Comprehensive analysis of the prognostic value and immune infiltration of FGFR family members in gastric cancer.

Background: Fibroblast growth factor receptors (FGFRs) modulate numerous cellular processes in tumor cells and tumor microenvironment. However, the effect of FGFRs on tumor prognosis and tumor-infiltrating lymphocytes in gastric cancer (GC) remains controversial. Methods: The expression of four different types of FGFRs was analyzed via GEPIA, TCGA-STAD, and GTEX databases and our 27 pairs of GC tumor samples and the adjacent normal tissue. Furthermore, the Kaplan-Meier plot and the TCGA database were utilized to assess the association of FGFRs with clinical prognosis. The R software was used to evaluate FGFRs co-expression genes with GO/KEGG Pathway Enrichment Analysis. In vitro and in vivo functional analyses and immunoblotting were performed to verify FGFR4 overexpression consequence. Moreover, the correlation between FGFRs and cancer immune infiltrates was analyzed by TIMER and TCGA databases. And the efficacy of anti-PD-1 mAb treatment was examined in NOG mouse models with overexpressed FGFR1 or FGFR4. Results: The expression of FGFRs was considerably elevated in STAD than in the normal gastric tissues and was significantly correlated with poor OS and PFS. ROC curve showed the accuracy of the FGFRs in tumor diagnosis, among which FGFR4 had the highest ROC value. Besides, univariate and multivariate analysis revealed that FGFR4 was an independent prognostic factor for GC patients. According to a GO/KEGG analysis, the FGFRs were implicated in the ERK/MAPK, PI3K-AKT and extracellular matrix (ECM) receptor signaling pathways. In vivo and in vitro studies revealed that overexpression of FGFR4 stimulated GC cell proliferation, invasion, and migration. In addition, FGFR1 expression was positively correlated with infiltrating levels of CD8+ T-cells, CD4+ T-cells, macrophages, and dendritic cells in STAD. In contrast, FGFR4 expression was negatively correlated with tumor-infiltrating lymphocytes. Interestingly, overexpression of FGFR1 in the NOG mouse model improved the immunotherapeutic impact of GC, while overexpression of FGFR4 impaired the effect. When combined with an FGFR4 inhibitor, the anti-tumor effect of anti-PD-1 treatment increased significantly in a GC xenograft mouse model with overexpressed FGFR4. Conclusions: FGFRs has critical function in GC and associated with immune cell infiltration, which might be a potential prognosis biomarker and predictor of response to immunotherapy in GC.

OTUD7B suppresses Smac mimetic-induced lung cancer cell invasion and migration via deubiquitinating TRAF3.

BACKGROUND: Smac mimetics are a type of drug that can induce apoptosis by antagonizing IAP family members in cancer treatment. However, a recent study showed that Smac mimetics can trigger cell invasion and migration in cancer cells by activating the NF-κB pathway. METHODS: We assessed lung cancer cell elongation, invasion and migration under treatment with the Smac mimetic LCL161. Functional analyses (in vitro and in vivo) were performed to detect the contribution of NIK and OTUD7B to LCL161-induced cell invasion and migration. The role of OTUD7B in regulation of the TRAF3/NIK/NF-κB pathway under LCL161 treatment was analysed by immunoblotting, immunoprecipitation, luciferase and ubiquitin assays, shRNA silencing and plasmid overexpression. Expression levels of OTUD7B, NIK and TRAF3 in tissue samples from lung cancer patients were examined by immunohistochemistry. RESULTS: We found that LCL161 stimulates lung cancer cell elongation, invasion and migration at non-toxic concentrations. Mechanistically, LCL161 results in NIK accumulation and activates the non-canonical rather than the canonical NF-κB pathway to enhance the transcription of target genes, such as IL-2 and MMP-9. Importantly, knockdown of NIK dramatically suppresses LCL161-induced cell invasion and migration by reducing the proteolytic processing of p100 to p52 and target gene transcription. Interestingly, we discovered that OTUD7B increases TRAF3 and decreases NIK to inhibit the non-canonical NF-κB pathway and that overexpression of OTUD7B suppresses LCL161-induced cell invasion and migration. Notably, OTUD7B directly binds to TRAF3 rather than to NIK and deubiquitinates TRAF3, thereby inhibiting TRAF3 proteolysis and preventing NIK accumulation and NF-κB pathway activation. Furthermore, the OTU domain of OTUD7B is required for the inhibition of LCL161-induced cell invasion and migration, as demonstrated by transfection of the C194S/H358R(CH) mutant OTUD7B. Finally, we investigated whether OTUD7B inhibits LCL161-induced lung cancer cell intrapulmonary metastasis in vivo, and our analysis of clinical samples was consistent with the above findings. CONCLUSIONS: Our study highlights the importance of OTUD7B in the suppression of LCL161-induced lung cancer cell invasion and migration, and the results are meaningful for selecting lung cancer patients suitable for LCL161 treatment.

Matrine suppression of self-renewal was dependent on regulation of LIN28A/Let-7 pathway in breast cancer stem cells.

Matrine, a natural product extracted from the root of Sophora flavescens Ait, was the main chemical ingredient of compounds of Kushen injection, which has been widely used for its remarkable anticancer effects for years. The underlying mechanisms for Matrine regulations of human breast cancer stem cells (BrCSCs) are barely known. LIN28, a well-characterized suppressor of Let-7 microRNA biogenesis, playing vital roles in regulations of stem cells' renewal and tumorigenesis. Here we show that the compounds of Kushen injection derived Matrine could suppress the BrCSCs differentiation and self-renewal through downregulating the expression of Lin28A, resulting in the inactivation of Wnt pathway through a Let-7b-dependent way. In opposite to Matrine, Cisplatin treatment increases the ability of tumorsphere formation and the expression of BrCSCs markers, which was partially blocked by either Let-7b overexpression or CCND1 inhibition. Furthermore, Matrine sensitized BrCSCs to cisplatin's suppression of cancer expansion in vitro and in vivo. Our study uncovers the role of the LIN28A/Let-7 in BrCSCs renewal, and more importantly, elucidated a novel mechanism by which Matrine induces breast cancer involution.

miR-497-5p inhibits tumor cell growth and invasion by targeting SOX5 in non-small-cell lung cancer.

MicroRNAs plays an important role in the ccurrence and development of non-small-cell lung cancer (NSCLC). miR-497-5p has been reported to function as a tumor suppressor in various cancers. However, the role of miR-497-5p in NSCLC remains poorly understood. In this study, we aimed to investigate the biological role and potential molecular mechanism of miR-497-5p in NSCLC. Our results showed that the messenger RNA (mRNA) expression level of miR-497-5p was notably downregulated in human NSCLC tissues and cell lines. miR-497-5p overexpression remarkably inhibited NSCLC cell proliferation and increased cell apoptosis in A549 and H460 cells, whereas inhibition of miR-497-5p had an opposite effect. The ability of cell migration and invasion was inhibited by miR-497-5p overexpression but was increased by miR-497-5p inhibition. Moreover, our findings indicated that SOX5 was a direct target of miR-497-5p. The protein and mRNA expression levels of SOX5 in A549 cells were remarkably inhibited by miR-497-5p overexpression but was upregulated by miR-497-5p inhibition. Furthermore, SOX5 overexpression notably reversed the effect of miR-497-5p mimic on NSCLC cell proliferation, cell apoptosis, cell migration, and invasion. Taken together, these results indicated that miR-497-5p overexpression inhibited NSCLC cell proliferation, migration and invasion, and induced cell apoptosis through inhibiting SOX5 gene expression. It was conceivable that miR-497-5p might serve as a potential molecular target for NSCLC treatment.

H19 regulation of oestrogen induction of symmetric division is achieved by antagonizing Let-7c in breast cancer stem-like cells.

OBJECTIVES: Breast cancer stem-like cells (BrCSCs) are the major reason for tumour generation, resistance and recurrence. The turbulence of their self-renewal ability could help to constrain the stem cell expansion. The way BrCSCs divided was related to their self-renewal capacity, and the symmetric division contributed to a higher ability. Non-coding long RNA of H19 was involved in multiple malignant procedures; the role and mechanistic proof of non-coding long RNA of H19 in controlling the divisions of BrCSCs were barely known. MATERIALS AND METHODS: Indicative functions of H19 in preclinical study were analysed by using the TCGA data base. Division manners were defined by using fluorescence staining. RESULTS: We identified the stimulation of H19 on symmetric division of BrCSCs, which subsequently resulted in self-renewing increasing. H19 inhibited the Let-7c availability by acting as its specific molecular sponge, and with Let-7c inhibition, oestrogen receptor activated Wnt signalling was unconstrained. Similarly, restoring Let-7c constrained oestrogen receptor activated Wnt factors, which sequentially inhibited the H19 decreasing of Let-7 bioavailability. Let-7c is reactivated in vitro where H19 was knockdown, and later inhibited the symmetric division of BrCSCs. Reciprocally, Wnt pathway activation leads to H19 increasing, which in turn decreased Let-7c bioavailability. CONCLUSIONS: Our results revealed a previously undescribed double negative feedback loop between sponge H19 and targeted Let-7c through oestrogen activated Wnt signalling that dominated in stem cells' division.

MYC and DNMT3A-mediated DNA methylation represses microRNA-200b in triple negative breast cancer.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with a poor prognosis. The microRNA-200 (miR-200) family has been associated with breast cancer metastasis. However, the epigenetic mechanisms underlying miR-200b repression in TNBC are not fully elucidated. In this study, we found that MYC proto-oncogene, bHLH transcription factor (MYC) and DNA methyltransferase 3A (DNMT3A) were highly expressed in TNBC tissues compared with other breast cancer subtypes, while miR-200b expression was inhibited significantly. We demonstrated that MYC physically interacted with DNMT3A in MDA-MB-231 cells. Furthermore, we demonstrated that MYC recruited DNMT3A to the miR-200b promoter, resulting in proximal CpG island hypermethylation and subsequent miR-200b repression. MiR-200b directly inhibited DNMT3A expression and formed a feedback loop in TNBC cells. MiR-200b overexpression synergistically repressed target genes including zinc-finger E-box-binding homeobox factor 1, Sex determining region Y-box 2 (SOX2), and CD133, and inhibited the migration, invasion and mammosphere formation of TNBC cells. Our findings reveal that MYC can collaborate with DNMT3A on inducing promoter methylation and miR-200b silencing, and thereby promotes the epithelial to mesenchymal transition and mammosphere formation of TNBC cells.

Prognostic Significance of Albumin-Globulin Score in Patients with Operable Non-Small-Cell Lung Cancer.

OBJECTIVE: This study was designed to evaluate the prognostic value of the preoperative albumin-globulin score (AGS) in the patients with non-small cell lung cancer (NSCLC) after pulmonary lobectomy. METHODS AND RESULTS: The optimal cutoff level was 40.00 and 27.05 g/L for Alb and Glb, respectively. Based on this and the previous study, patients with both an hypoalbuminemia (< 40.00 g/L) and an elevated Glb level (≥ 27.05 g/L) were assigned a score of 2, and patients with one or neither were assigned a score of 1 or 0, respectively. We investigated the correlations between the AGS and the clinicopathological characteristics of patients and found that AGS was significantly associated with TNM stage (P = 0.016). Multivariate Cox analyses indicated that the AGS was an independent prognostic indicator for NSCLC for disease-free survival (DFS) (P = 0.001) and overall survival (OS) (P = 0.004). Kaplan-Meier analysis and log-rank test demonstrated that there were significant differences in DFS (P < 0.001) and OS (P < 0.001) among the three AGS groups. Furthermore, our study showed that DFS and OS are significantly different in three groups of patients with different AGS, in both Squamous carcinoma (P < 0.001 for DFS; P < 0.001 for OS) or adenocarcinoma (P = 0.034 for DFS; P = 0.035 for OS). In addition, we enrolled 53 patients as an independent set of cases for the further validation of AGS. Multivariate analyses verified AGS was an independent prognostic factor for NSCLC patients (P = 0.020 for DFS; P = 0.018 for OS). CONCLUSIONS: Preoperative AGS is an independent prognostic factor for patients with operable NSCLC.

SNHG6 functions as a competing endogenous RNA to regulate E2F7 expression by sponging miR-26a-5p in lung adenocarcinoma.

Increasing evidence has highlighted the pivotal roles of deregulated long non-coding RNAs (lncRNAs) in tumourigenesis. However, the biological functions and mechanisms of lncRNAs in human lung adenocarcinoma (LUAD) remain elusive. Small nucleolar RNA host gene 6 (SNHG6), a novel lncRNA, is aberrantly expressed in various cancers. In this study, SNHG6 was upregulated in LUAD tissues, and its upregulation was positively associated with advanced TNM stage, large tumour size and poor overall survival (OS) in LUAD patients. Gain- and loss-of-function experiments confirmed that SNHG6 promoted cell cycle progression, cell proliferation, migration and invasion, and epithelial-mesenchymal transition (EMT) in vitro. Animal experiments demonstrated that SNHG6 knockdown remarkably inhibited xenograft formation in vivo. Moreover, mechanistic experiments identified that SNHG6 functions as a competing endogenous RNA (ceRNA) through competitively sponging miR-26a-5p to regulate E2F7 expression, cell motility and EMT in LUAD cells. In summary, our findings reveal that SNHG6 may act as an oncogenic lncRNA in LUAD carcinogenesis by regulating the miR-26a-5p/E2F7 axis.

A miR-26a/E2F7 feedback loop contributes to tamoxifen resistance in ER-positive breast cancer.

Tamoxifen (TAM) resistance is a substantial challenge in the treatment of estrogen receptor (ER)-positive breast cancer. Previous studies have revealed an important role of microRNA (miRNA/miR)-26a in TAM resistance in breast cancer. However, the mechanism underlying the regulatory effects of miR-26a on TAM resistance remains to be elucidated. The expression levels of miR-26a in ER-positive breast cancer were detected by reverse transcription-quantitative polymerase chain reaction. E2F transcription factor 7 (E2F7) and MYC proto-oncogene, bHLH transcription factor (MYC) levels were detected by western blotting. The present study demonstrated that miR-26a expression was reduced in ER-positive breast cancer compared with in normal breast tissues, whereas E2F7 expression was significantly elevated. Furthermore, an inverse correlation between miR-26a and E2F7 expression was detected in ER-positive breast cancer. The results indicated that miR-26a directly inhibited E2F7 expression through translational inhibition and indirectly inhibited MYC expression partly via E2F7 repression. E2F7, in turn, decreased miR-26a expression via MYC-induced transcriptional inhibition of miRNAs. Furthermore, transfection with miR-26a mimics increased the expression of its host genes (CTD small phosphatase like and CTD small phosphatase 2), whereas ectopic E2F7 expression abrogated the effects of miR-26a. These findings indicated that miR-26a and E2F7 may form a double-negative feedback loop, resulting in downregulation of miR-26a and upregulation of E2F7 in ER-positive breast cancer. Both miR-26a knockdown and E2F7 overexpression conferred resistance to TAM in MCF-7 cells. Conversely, miR-26a overexpression and E2F7 silencing resensitized MCF-7 resistant cells to TAM. These findings revealed that a feedback loop between miR-26a and E2F7 may promote TAM resistance in ER-positive breast cancer.

FBXW7 suppresses epithelial-mesenchymal transition and chemo-resistance of non-small-cell lung cancer cells by targeting snai1 for ubiquitin-dependent degradation.

OBJECTIVES: FBXW7 acts as a tumour suppressor by targeting at various oncoproteins for ubiquitin-mediated degradation. However, the clinical significance and the involving regulatory mechanisms of FBXW7 manipulation of NSCLC regeneration and therapy response are not clear. MATERIALS AND METHODS: Immunohistochemical staining and qRT-PCR were applied to detect FBXW7 and Snai1 expression in 100 samples of NSCLC and matched tumour-adjacent tissues. FBXW7 manipulation of cancer biological functions were studied by using MTT assay, immunoblotting, flow cytometry, transwells, wound healing assay, and sphere-formation assays. Immunofluorescence and co-immunoprecipitation were used to analyse the possible interaction between Snai1 and FBXW7. RESULTS: We detected the decreased FBXW7 expression in majority of the NSCLC tissues, and lower FBXW7 level was correlated with advanced TNM stage. Furthermore, those patients with decreased FBXW7 expression tend to have both poorer 5-year survival outcomes, and shorter disease-free survival, comparing to those with higher FBXW7 levels. Functionally, we found that FBXW7 enforcement suppressed NSCLC progression by inducing cell growth arrest, increasing chemo-sensitivity and inhibiting Epithelial-mesenchymal Transition (EMT) progress. Results further showed that FBXW7 could interact with Snai1 directly to degrade its expression through ubiquitylating alternation in NSCLC, which could be partially abrogated by restoring Snai1 expression. CONCLUSIONS: FBXW7 conduction of tumour suppression was partly through degrading Snai1 directly for ubiquitylating regulation in NSCLC.

Retrospective observational cohort study on cosmetic outcome of using Ti-Ni memory alloy wire for intradermal suture following mastectomy in patients with breast cancer.

The method of suturing for incisions is crucial for the comprehensive treatment of clinical patients with breast cancer. Suturing is considered a major part of post-surgical recovery and may serve as a marker for evaluation of surgical outcome. The present study aimed to establish an effective means of suturing for patients who received modified radical surgery that helps to improve the cosmetic outcome of the incision. Enrolled patients were divided into an active and a control group. Ti-Ni memory alloy wire for intradermal suture in the active group and silk for interruption suture in the control group were applied to assess the different prognosis-associated factors. The Vancouver Scar Scale (VSS) was used to evaluate the wound size and the recovery time of the scars. The association between diabetes and the number of days of wound healing was also analyzed. The results indicated that the mean VSS score of the active group was decreased compared with that of the control group (P<0.001). The VSS scores of four main features (vascularity, pigmentation, pliability and height) between the two groups also statistically differed (P<0.001). Furthermore, the mean number of days of wound healing was significantly decreased for the active group compared with that for the control group (P=0.0026) in the patients with diabetes. In addition, the usage of Ti-Ni memory alloy wire was able to decrease the mean number of wound healing days between patients with diabetes and their non-diabetic counterparts (P=0.7009). The present study indicated that intradermal suture offers improved cosmetic outcome for patients undergoing mastectomy with or without axillary surgery. This technique may be useful for preventing scar overgrowth and for facilitating the recovery process in patients with diabetes.

The efficacy and safety of anti-PD-1/PD-L1 antibody therapy versus docetaxel for pretreated advanced NSCLC: a meta-analysis.

Antibodies against the immune checkpoint proteins PD-1 and PD-L1 are novel therapeutic drugs for the treatment of advanced non-small cell lung cancer (NSCLC). Many clinical trials involving these drugs achieved breakthroughs in patients previously treated for advanced NSCLC. However, the results of these clinical studies are not consistent. In this report, we performed a meta-analysis to assess the efficacy and safety of anti-PD-1/PD-L1 antibodies compared with docetaxel treatment for advanced NSCLC patients from 5 randomized clinical trials. We demonstrated that the patients in anti-PD-1/PD-L1 antibody therapy groups had significantly longer overall survival (OS) (HR = 0.69, 95% CI 0.63-0.75, P < 0.05) and progression-free survival (PFS) (HR = 0.76, 95% CI 0.63-0.92, P < 0.05) than those in chemotherapy groups, especially PD-L1 positive patients. Anti-PD-1/PD-L1 antibodies improved the objective response rate (ORR) compared with docetaxel (OR = 1.64, 95% CI 1.19-2.26, p < 0.05). In addition, the anti-PD-1/PD-L1 antibody therapy had fewer treatment-related adverse events (AEs) (OR = 0.33, 95% CI 0.28-0.39, P < 0.05) than docetaxel, especially the grade ≥3 AEs (OR = 0.18, 95% CI 0.12-0.28, P < 0.001). In conclusion, our study revealed that, compared with docetaxel, anti-PD-1/PD-L1 antibody therapy improved clinical efficacy and safety in previously treated advanced NSCLC patients. This therapy may be a promising treatment for advanced NSCLC patients.

Breast cancer stem-like cells are sensitized to tamoxifen induction of self-renewal inhibition with enforced Let-7c dependent on Wnt blocking.

Let-7 microRNAs have been reported to have tumor suppressive functions; however, the effect of Let-7 when used in combination with chemotherapies is uncertain, but may have potential for use in clinical practice. In this study, we used RT-qPCR, western blot analysis, cell proliferation assay, flow cytometry analysis, immunohistochemistry (IHC) staining, luciferase assays, cell sorting analysis and xenografted tumor model to explore the role of Let-7 in the chemotherapy sensitivity of breast cancer stem cells. The findings of the current study indicated that Let­7 enhances the effects of endocrine therapy potentially by regulating the self­renewal of cancer stem cells. Let­7c increased the anticancer functions of tamoxifen and reduced the ratio of cancer stem­like cells (CSCs), sensitizing cells to therapy-induced repression in an estrogen receptor (ER)­dependent manner. Notably, Let­7 decreased the tumor formation ability of estrogen­treated breast CSCs in vivo and suppressed Wnt signaling, which further consolidated the previously hypothesis that Let­7 decreases the self­renewal ability, contributing to reduced tumor formation ability of stem cells. The suppressive effects exerted by Let­7 on stem­like cells involved Let­7c/ER/Wnt signaling, and the functions of Let­7c exerted with tamoxifen were dependent on ER. Taken together, the findings identified a biochemical and functional link between Let­7 and endocrine therapy in breast CSCs, which may facilitate clinical treatment in the future using delivery of suppressive Let-7.

Clinical Application of Detecting 21-Gene Recurrence Score in Predicating Prognosis and Therapy Response of Patients with Breast Cancer from Two Medical Centers.

To determine the most suitable strategy in treating patients with invasive breast cancer from Northwest China. Lower recurrence score (RS) correlated with lower recurrence ratio. Patients having a medium-high 21-gene RS who received adjuvant therapy presented lower recurrence risk. Younger patients having RS results (⩾31) tended to accept adjuvant therapy more often, however, those having intermediate RS results were inclined to wait and did not receive chemotherapy. These results suggested that RS-based precision medicine will allow individualized diagnosis and treatment, resulting in better outcomes and preserved medical resources.

MiR-129 blocks estrogen induction of NOTCH signaling activity in breast cancer stem-like cells.

Stem-like cells in tumor group featured the major role in the chemotherapy resistance of breast cancer, and the reduction of stem-like cells helped to perish the tumor when receiving chemotherapy. Smaller stem cells number indicated better therapeutic effect in vitro and in clinics, but how did miR-129 and Notch signaling function in breast cancer stem-like cells (BrCSCs) were unclear yet. Through using sphere forming assay and FACS sorting, we found that miR-129 decreased the proportion of stem-like cells in breast cancer cells. Results further indicated that miR-129 degraded the Estrogen Receptor 1 (ESR1) mRNA through a post-translational manner and contributed to the decline of stem-like cells number, preventing tumor regeneration. Cyclin d1 and DICER 1 were proved to promote Let-7 maturation, and in present study, we proved that miR-129 exhibited inhibition on ESR1 and halted the cyclin d1/DICER 1 sustaining of Let-7, which consequently released the Let-7 degradation of NUMB. The restoration of suppressive NUMB by upregulating miR-129 resulted in NOTCH signaling inhibition. In conclusion, we demonstrated the negative regulation of miR-129 on NOTCH signaling activation in BrCSCs' renewal, which was achieved via continuous suppression on cyclin d1/DICER1 sustaining of Let-7 level, and eventually rescued the targeted inhibition of NUMB. The miR-129/ESR1 signaling played pivotal role in controlling DICER1/Let-7/NOTCH cascade via cyclin d1, revealing the novel mechanism of dual Let-7 in non-coding genes network.

Analysis of risk factors for post-operative complications and prognostic predictors of disease recurrence following definitive treatment of patients with esophageal cancer from two medical centers in Northwest China.

Evaluating the clinicopathological features of patients receiving definitive treatment for esophageal cancer may facilitate the identification of patterns and factors associated with post-operative complications, and enable the development of a surveillance strategy for surviving patients at a higher risk of disease recurrence. In the present study, clinical data from 579 patients with esophageal cancer that underwent radical resection of esophagus were collected. These patients were admitted to two medical centers in Northwest China, and information regarding the presence or absence of basic chronic diseases and post-operative results were retrospectively analyzed. The level of selected stem cell markers, including aldehyde dehydrogenase 1, CD133, integrin subunit α 6, integrin subunit ß 4 and T-cell factor-4, were determined in esophageal cancer tissue samples in order to determine whether these markers may be useful predictors of disease prognosis and recurrence. Post-operative complications in patients receiving radical resection of the esophagus included respiratory system complications, cardiovascular abnormalities and esophageal anastomotic fistulae. Diabetes, basic respiratory disease and lower pre-surgical serum albumin levels were observed to be individual risk factors associated with post-operative complications, including respiratory system complications of acute respiratory failure and pulmonary infection, cardiovascular abnormalities of atrial fibrillation and arrhythmia, as well as the development of esophageal anastomotic fistulae. Diagnosis of esophageal cancer at later stage was significantly correlated with anastomotic fistula. Molecular detection of stem cell markers for prognosis prediction was achieved by immunohistochemical and immunofluorescence staining assays. The results demonstrated that the presence of stem-like cells in cancer tissues was associated with poor disease prognosis and a high recurrence ratio. In conclusion, the results of the current study suggested that post-operative complications were more likely to occur in patients with diabetes, basic respiratory disease or lower serum albumin levels prior to surgery. Therefore, sufficient intensive peri-operative care, rigorous operative risk assessments, and the selection of the patients with early or mid-stage esophageal cancer, may decrease the risk of post-surgical complications in patients receiving radical resection of the esophagus. In addition, a high ratio of esophageal cancer stem-like cells was associated with cancer recurrence. These results suggest that an intensive surveillance strategy should be implemented in order to facilitate early detection of disease recurrence and improve the clinical management of these patients post-surgery.

miR-367 promotes tumor growth by inhibiting FBXW7 in NSCLC.

miR-367 is one of the most abundant miRNAs in human embryonic stem cells (hESCs) and is mainly involved in maintaining the pluripotency of stem cells. However, its role in cancer development remains poorly understood. In the present study, we explored the function and mechanism of the endogenous miR-367 in non-small cell lung cancer (NSCLC). In the present study, we demonstrated that the level of miR-367 in NSCLC was significantly higher than that in adjacent normal tissues, and its upregulation was positively correlated with tumor size, tumor differentiation and tumor-node-metastasis (TNM) stage. miR-367 was an indicator of a poorer prognosis in NSCLC patients. Furthermore, overexpression of miR-367 significantly inhibited apoptosis and enhanced proliferation by promoting cell cycle transition from G1 to S phase. In contrast, knockdown of miR-367 markedly reversed the cellular events observed with miR-367 overexpression. Moreover, we identified that F-box and WD repeat domain-containing 7 (FBXW7) is a novel target of miR-367. It reverses the oncogenic effects of miR-367 by downregulating its substrates, c-Myc and c-Jun, in NSCLC cells. Finally, studies in vivo revealed that knockdown of miR-367 inhibited the growth of xenografts in the nude mice by increasing the expression of FBXW7. In summary, our findings indicate that miR-367 exerts tumor-promoting effect by negatively regulating FBXW7 in NSCLC, and it could become a potential therapeutic target for NSCLC intervention.

LCL161 increases paclitaxel-induced apoptosis by degrading cIAP1 and cIAP2 in NSCLC.

BACKGROUND: LCL161, a novel Smac mimetic, is known to have anti-tumor activity and improve chemosensitivity in various cancers. However, the function and mechanisms of the combination of LCL161 and paclitaxel in non-small cell lung cancer (NSCLC) remain unknown. METHODS: Cellular inhibitor of apoptotic protein 1 and 2 (cIAP1&2) expression in NSCLC tissues and adjacent non-tumor tissues were assessed by immunohistochemistry. The correlations between cIAP1&2 expression and clinicopathological characteristics, prognosis were analyzed. Cell viability and apoptosis were measured by MTT assays and Flow cytometry. Western blot and co-immunoprecipitation assay were performed to measure the protein expression and interaction in NF-kB pathway. siRNA-mediated gene silencing and caspases activity assays were applied to demonstrate the role and mechanisms of cIAP1&2 and RIP1 in lung cancer cell apoptosis. Mouse xenograft NSCLC models were used in vivo to determine the therapeutic efficacy of LCL161 alone or in combination with paclitaxel. RESULTS: The expression of cIAP1 and cIAP2 in Non-small cell lung cancer (NSCLC) tumors was significantly higher than that in adjacent normal tissues. cIAP1 was highly expressed in patients with late TNM stage NSCLC and a poor prognosis. Positivity for both cIAP1 and cIAP2 was an independent prognostic factor that indicated a poorer prognosis in NSCLC patients. LCL161, an IAP inhibitor, cooperated with paclitaxel to reduce cell viability and induce apoptosis in NSCLC cells. Molecular studies revealed that paclitaxel increased TNFα expression, thereby leading to the recruitment of various factors and the formation of the TRADD-TRAF2-RIP1-cIAP complex. LCL161 degraded cIAP1&2 and released RIP1 from the complex. Subsequently, RIP1 was stabilized and bound to caspase-8 and FADD, thereby forming the caspase-8/RIP1/FADD complex, which activated caspase-8, caspase-3 and ultimately lead to apoptosis. In nude mouse xenograft experiments, the combination of LCL161 and paclitaxel degraded cIAP1,2, activated caspase-3 and inhibited tumor growth with few toxic effects. CONCLUSION: Thus, LCL161 could be a useful agent for the treatment of NSCLC in combination with paclitaxel.