Deletion of the tyrosine phosphatase Shp2 in cervical cancer cells promotes reprogramming of glutamine metabolism.

Shp2 is a nonreceptor protein tyrosine phosphatase that is overexpressed in cervical cancer. However, the role of Shp2 in the regulation of cervical cancer metabolism and tumorigenesis is unclear. EGFR signaling pathways are commonly dysregulated in cervical cancer. We showed that Shp2 knockout in cervical cancer cells decreased EGFR expression and downregulated downstream RAS-ERK activation. Although AKT was activated in Shp2 knockout cells, inhibition of AKT activation could not make cells more sensitive to death. Shp2 depletion inhibited cervical cancer cell proliferation and reduced tumor growth in a xenograft mouse model. 1 H NMR spectroscopic analysis showed that glutamine, glutamate, succinate, creatine, glutathione, and UDP-GlcNAc were significantly changed in Shp2 knockout cells. The intracellular glutamine level was higher in Shp2 knockout cells than in control cells. Further analysis demonstrated that Shp2 knockout promoted glutaminolysis and glutathione production by up-regulating the glutamine metabolism-related genes such as glutaminase (GLS). However, inhibition of GLS did not always make cells sensitive to death, which was dependent on glucose concentration. The level of oxidative phosphorylation was significantly increased, accompanied by an increased generation of reactive oxygen species in Shp2 knockout cells. Shp2 deficiency increased c-Myc and c-Jun expression, which may be related to the upregulation of glutamine metabolism. These findings suggested that Shp2 regulates cervical cancer proliferation, glutamine metabolism, and tumorigenicity.

Tailored Fluorosurfactants through Controlled/Living Radical Polymerization for Highly Stable Microfluidic Droplet Generation.

Droplet-based microfluidics represents a disruptive technology in the field of chemistry and biology through the generation and manipulation of sub-microlitre droplets. To avoid droplet coalescence, fluoropolymer-based surfactants are commonly used to reduce the interfacial tension between two immiscible phases to stabilize droplet interfaces. However, the conventional preparation of fluorosurfactants involves multiple steps of conjugation reactions between fluorinated and hydrophilic segments to form multiple-block copolymers. In addition, synthesis of customized surfactants with tailored properties is challenging due to the complex synthesis process. Here, we report a highly efficient synthetic method that utilizes living radical polymerization (LRP) to produce fluorosurfactants with tailored functionalities. Compared to the commercialized surfactant, our surfactants outperform in thermal cycling for polymerase chain reaction (PCR) testing, and exhibit exceptional biocompatibility for cell and yeast culturing in a double-emulsion system. This breakthrough synthetic approach has the potential to revolutionize the field of droplet-based microfluidics by enabling the development of novel designs that generate droplets with superior stability and functionality for a wide range of applications.

The natural product dehydrocurvularin induces apoptosis of gastric cancer cells by activating PARP-1 and caspase-3.

The natural product dehydrocurvularin (DSE2) is a fungal-derived macrolide with potent anticancer activity, but the mechanism is still unclear. We found that DSE2 effectively inhibited the growth of gastric cancer cells and induced the apoptosis by activating Poly(ADP-ribose) polymerase 1 (PARP-1) and caspase-3. Pharmacological inhibition and genetic knockdown with PARP-1 or caspase-3 suppressed DSE2-induced apoptosis. PARP-1 was previously reported to be cleaved into fragments during apoptosis. However, PARP-1 was barely cleaved in DSE2-induced apoptosis. DSE2 induced PARP-1 activation as indicated by rapid depletion of NAD+ and the concomitant formation of poly(ADP-ribosylated) proteins (PARs). Interestingly, the PARP-1 inhibitor (Olaparib) attenuated the cytotoxicity of DSE2. Moreover, the combination of Olaparib and Z-DEVD-FMK (caspase-3 inhibitor) further reduced the cytotoxicity. It has been shown that PARP-1 activation triggers cytoplasm-nucleus translocation of apoptosis-inducing factor (AIF). Caspase-3 inhibitors inhibited PARP-1 activation and suppressed PARP-1-induced AIF nuclear translocation. These results indicated that DSE2-induced caspase-3 activation may occur before PARP-1 activation. The ROS inhibitor, N-acetyl-cysteine, significantly inhibited the activation of caspase-3 and PARP-1, indicating that ROS overproduction contributed to DSE2-induced apoptosis. Using an in vivo approach, we further found that DSE2 significantly inhibited gastric tumor growth and promoted translocation of AIF to the nucleus. In conclusion, DSE2 induces gastric cell apoptosis by activating caspase-3 and PARP-1, and shows potent antitumor activity against human gastric carcinoma in vitro and in vivo.

Expression profiles and functional prediction of histone acetyltransferases of the MYST family in kidney renal clear cell carcinoma.

BACKGROUND: Histone acetyltransferases (HATs) of the MYST family are associated with a variety of human cancers. However, the relationship between MYST HATs and their clinical significance in kidney renal clear cell carcinoma (KIRC) has not yet been evaluated. METHODS: The bioinformatics method was used to investigate the expression patterns and prognostic value of MYST HATs. Western blot was used to detect the expression of MYST HATs in KIRC. RESULTS: The expression levels of MYST HATs except KAT8 (KAT5, KAT6A, KAT6B, and KAT7) were significantly reduced in KIRC tissues compared to normal renal tissues, and the western blot results of the KIRC samples also confirmed the result. Reduced expression levels of MYST HATs except KAT8 were significantly associated with high tumor grade and advanced TNM stage in KIRC, and showed a significant association with an unfavorable prognosis in patients with KIRC. We also found that the expression levels of MYST HATs were closely related to each other. Subsequently, gene set enrichment analysis showed that the function of KAT5 was different from that of KAT6A, KAT6B and KAT7. The expression levels of KAT6A, KAT6B and KAT7 had significant positive correlations with cancer immune infiltrates such as B cells, CD4+ T cells and CD8+ T cells. CONCLUSIONS: Our results indicated that MYST HATs, except KAT8, play a beneficial role in KIRC.

Comparison of Outcomes Following Total Hip Arthroplasty Between Patients Diagnosed with Association Research Circulation Osseous (ARCO) Stage III and Stage IV Osteonecrosis of the Femoral Head: A Retrospective Study of 302 Patients.

BACKGROUND This retrospective study from a single center aimed to compare outcomes following total hip arthroplasty (THA) in 302 patients diagnosed with Association Research Circulation Osseous (ARCO) stage III and stage IV osteonecrosis of the femoral head (ONFH). MATERIAL AND METHODS The study included 302 patients who underwent THA for ONFH between January 2018 and September 2021. Patient groups included ARCO stage III (n=145) and ARCO stage IV (n=157). Outcomes measured included duration of disease, operative time, intraoperative blood volume, postoperative length of hospital stay, pain measured by the visual analog scale (VAS) score, Harris hip score (HHS), and forgotten joint score (FJS). RESULTS Patients with ARCO stage III ONFH had a significantly shorter operative time (P=0.009), shorter length of hospital stay (P=0.021), and reduced volume of intraoperative bleeding (P=0.021) compared with patients with ARCO stage IV ONFH. There were no significant differences in disease duration (P=0.310), postoperative complications (P=0.07), preoperative (P=0.086, P=0.156) and postoperative (P=0.062, P=0.173) HHS and VAS scores, respectively. Patients with stage III ONFH reported significantly higher FJS scores at 3 months, 6 months, and 1 year after THA. CONCLUSIONS Patients who underwent hip arthroplasty for ARCO stage III femoral head necrosis experienced shorter operative time and hospital stay, less intraoperative bleeding, and better restoration of hip function than those with ARCO stage IV. Moreover, stage III patients were more prone to "forget" their hip arthroplasty experience within 1 year of surgery.

lncRNA ZNF649-AS1 Induces Trastuzumab Resistance by Promoting ATG5 Expression and Autophagy.

The regulatory mechanism of long non-coding RNAs (lncRNAs) in trastuzumab resistance is not well established to date. In this research, we identified differentially expressed lncRNA and investigated its regulatory role in trastuzumab resistance of breast cancer. HiSeq sequencing and quantitative real-time PCR were performed to identify the dysregulated lncRNAs. Mass spectrometry, RNA fluorescence in situ hybridization (RNA-FISH), and immunoprecipitation assays were performed to identify the direct interactions between ZNF649-AS1 and other associated targets, such as polypyrimidine tract binding protein 1 (PTBP1) and autophagy related 5 (ATG5). Our results showed that ZNF649-AS1 was more highly expressed in trastuzumab-resistant cells compared to sensitive cells. Increased expression of ZNF649-AS1 was associated with a poorer response and shorter survival time of breast cancer patients. ZNF649-AS1 was upregulated by H3K27ac modification at the presence of trastuzumab treatment, and knockdown of ZNF649-AS1 reversed trastuzumab resistance via modulating ATG5 expression and autophagy. Mechanically, ZNF649-AS1 was associated with PTBP1 protein, which further promoted the transcription activity of the ATG5 gene. In conclusion, we demonstrated that H3K27ac modification-induced upregulation of ZNF649-AS1 could cause autophagy and trastuzumab resistance through associating with PTBP1 and promoting ATG5 transcription.

Exosome-mediated lncRNA AFAP1-AS1 promotes trastuzumab resistance through binding with AUF1 and activating ERBB2 translation.

BACKGROUND: Although trastuzumab provides significant clinical benefit for HER2-positive breast cancers, responses are limited by the emergence of resistance. Recent evidence suggests that long noncoding RNAs (lncRNAs) play important roles in tumorigenesis and chemoresistance. However, the regulatory mechanism of lncRNAs in trastuzumab resistance is not well established to date. In this research, we identified the differentially expressed lncRNA and investigated its regulatory role in trastuzumab resistance of breast cancer. METHODS: LncRNA microarray and qRT-PCR were performed to identify the dysregulated lncRNAs. Transmission electron microscopy, differential ultracentrifugation and qRT-PCR were used to verify the existence of exosomal AFAP1-AS1 (actin filament associated protein 1 antisense RNA 1). Bioinformatics prediction, RNA fluorescence in situ hybridization (RNA-FISH) and immunoprecipitation assays were performed to identify the direct interactions between AFAP1-AS1 and other associated targets, such as AU-binding factor 1 (AUF1) and ERBB2. Finally, a series gain- or loss-functional assays were done to prove the precise role of AFAP1-AS1 in trastuzumab resistance. RESULTS: AFAP1-AS1 was screened out due to its higher expression in trastuzumab-resistant cells compared to sensitive cells. Increased expression of AFAP1-AS1was associate with poorer response and shorter survival time of breast cancer patients. AFAP1-AS1 was upregulated by H3K27ac modification at promoter region, and knockdown of AFAP1-AS1 reversed trastuzumab resistance. Moreover, extracellular AFAP1-AS1 secreted from trastuzumab resistant cells was packaged into exosomes and then disseminated trastuzumab resistance of receipt cells. Mechanically, AFAP1-AS1 was associated with AUF1 protein, which further promoted the translation of ERBB2 without influencing the mRNA level. CONCLUSION: Exosomal AFAP1-AS1 could induce trastuzumab resistance through associating with AUF1 and promoting ERBB2 translation. Therefore, AFAP1-AS1 level may be useful for prediction of trastuzumab resistance and breast cancer treatment.

c-Myc mediated upregulation of long noncoding RNA SNHG12 regulates proliferation and drug sensitivity in natural killer/T-cell lymphoma.

Nasal-type natural killer/T-cell lymphoma (NKTCL) is an aggressive malignancy with poor outcomes. The treatment of NKTCL requires intensive chemotherapy. Long noncoding RNAs (lncRNAs) have been implicated in many cancers, including NKTCL. The elucidation of the multidrug resistance (MDR) may greatly contribute to explore novel therapeutic strategies. Herein, we explored the roles and potential regulatory mechanism of lncRNAs small nucleolar RNA host gene 12 (SNHG12) in MDR of NKTCL. We found that SNHG12 was upregulated in NKTCL tissue sections, and its high expression was positively correlated with clinical grade of malignancy of NKTCL. c-Myc and SNHG12 expression was upregulated in NKTCL cell lines. c-Myc- and SNHG12 overexpression promoted proliferation and inhibited sensitivity to cisplatin (CDDP) in NK/T-cell lymphoma cell line YTS cells, and c-Myc and SNHG12-downregulation inhibited proliferation and enhanced sensitivity to CDDP in SNK-6 cells. Moreover, c-Myc- and SNHG12 overexpression increased Ki67 and P-gp expression in YTS cells, whereas c-Myc and SNHG12-downregulation reduced the Ki67 and P-gp expression in SNK-6 cells. Correlational analyses revealed that c-Myc expression was positively correlated with SNHG12 expression in NKTCL tissues. Mechanism research showed that SNHG12 was a direct transcriptional target of c-Myc and c-Myc promoted SNHG12 expression in NKTCL cell lines. Further research showed that SNHG12 overexpression reversed the effects of c-Myc downregulation on proliferation and sensitivity to CDDP in NKTCL cell lines. Taken together, our findings first report that c-Myc mediated upregulation of SNHG12 promotes proliferation and inhibits drug sensitivity in NKTCL, which provides new insights into the therapeutic target for NKTCL.

TIPE2 suppresses progression and tumorigenesis of esophageal carcinoma via inhibition of the Wnt/ß-catenin pathway.

BACKGROUND: Esophageal carcinoma is the eighth prevalent malignancy and ranks the sixth in carcinoma-related death worldwide. Tumor necrosis factor-α-induced protein-8 like-2 (TIPE2) has been identified as a tumor suppressor in multiple carcinomas. However, its roles and molecular mechanisms underlying esophageal carcinoma progression are still undefined till now. METHODS: RT-qPCR assay was employed to detect the expression of TIPE2 mRNA. TIPE2 protein expression was measured by using western blot assay. Ad-V and Ad-TIPE2 adenoviruses were constructed to overexpress TIPE2. The effects of TIPE2 overexpression on cell proliferation, invasion and apoptosis were assessed by MTT and Edu incorporation assays, transwell invasion assay and flow cytometry analysis, respectively. The effect of TIPE2 overexpression on xenograft tumor growth was determined by measuring tumor volume and weight, together with immunohistochemistry assay. The effect of TIPE2 overexpression on the Wnt/ß-catenin signaling pathway was evaluated by detecting the protein levels of ß-catenin, c-Myc and cyclinD1 in EC9076 cells and xenograft tumors of esophageal carcinoma. RESULTS: TIPE2 expression was downregulated in esophageal carcinoma tissues and cells. Adenovirus-mediated TIPE2 overexpression suppressed cell proliferation and invasion, and induced apoptosis in esophageal carcinoma cells. Enforced expression of TIPE2 inhibited tumor growth in vivo, as evidenced by the reduced tumor volume, tumor weight and proliferating cell nuclear antigen expression. Overexpression of TIPE2 inhibited the Wnt/ß-catenin signaling pathway in esophageal carcinoma in vitro and in vivo. CONCLUSIONS: These results suggest that TIPE2 suppressed progression and tumorigenesis of esophageal carcinoma via inhibition of the Wnt/ß-catenin pathway.

S100A4 participates in epithelial-mesenchymal transition in breast cancer via targeting MMP2.

Numerous studies have shown that S100A4 acquires its metastasis-promoting effects via inducing epithelial-mesenchymal transition (EMT). However, its role and mechanism in EMT in breast cancer had not been clearly elucidated. Herein, we showed that the knockdown of S100A4 expression in breast cancer cell lines, MDA-MB-231 and MDA-MB-468, inhibited not only cell invasion ability greatly, but also the occurrence of EMT significantly. In addition, S100A4 knockdown could also decrease the expression of MMP2, a promoter and a mediator of the EMT processes in cancer. Above all, restoring the expression of MMP2 in MDA-MB-231 and MDA-MB-468 could not only rescue the invasion ability inhibited by knockdown of S100A4, but also reverse the EMT suppressed by knockdown of S100A4. In summary, our results indicated that S100A4 could promote the invasion ability of breast cancer cells via EMT, more importantly, it could participate in EMT via regulating MMP2 in breast cancer. Therefore, S100A4 could be a candidate biomarker for defining breast cancer metastasis and useful target for therapy.

Site-selective and metal-free aliphatic C-H oxidation enabled synthesis of [5,24,25-D3]-(25S)-Δ(7)-dafachronic acid.

Steroid hormones play significant roles in both worms and mammalians. (25S)-Δ(7)-Dafachronic acid (Δ(7)-DA, 1) is a member of the dafachronic acid hormonal series that regulates both development and lifespan of C. elegans. Despite its importance, effective tools for the illumination of its mode of action are lacking. Herein, we report an efficient synthesis of trideuterated Δ(7)-DA, [5,24,25-D3]-(25S)-Δ(7)-dafachronic acid ([D3]-Δ(7)-DA, 2), as a useful chemical tool for subsequent biological studies. Key steps for this bioinspired synthesis approach include site-selective aliphatic C-H oxidation mediated by methyl(trifluoromethyl)dioxirane (TFDO), and the iridium/phosphine-oxazoline-catalyzed late-stage asymmetric deuterium reduction.

Advancing Tissue Culture with Light-Driven 3D-Printed Microfluidic Devices.

Three-dimensional (3D) printing presents a compelling alternative for fabricating microfluidic devices, circumventing certain limitations associated with traditional soft lithography methods. Microfluidics play a crucial role in the biomedical sciences, particularly in the creation of tissue spheroids and pharmaceutical research. Among the various 3D printing techniques, light-driven methods such as stereolithography (SLA), digital light processing (DLP), and photopolymer inkjet printing have gained prominence in microfluidics due to their rapid prototyping capabilities, high-resolution printing, and low processing temperatures. This review offers a comprehensive overview of light-driven 3D printing techniques used in the fabrication of advanced microfluidic devices. It explores biomedical applications for 3D-printed microfluidics and provides insights into their potential impact and functionality within the biomedical field. We further summarize three light-driven 3D printing strategies for producing biomedical microfluidic systems: direct construction of microfluidic devices for cell culture, PDMS-based microfluidic devices for tissue engineering, and a modular SLA-printed microfluidic chip to co-culture and monitor cells.

Fluorine-modified polymers reduce the adsorption of immune-reactive proteins to PEGylated gold nanoparticles.

Aim: To investigate the influence of fluorine in reducing the adsorption of immune-reactive proteins onto PEGylated gold nanoparticles. Methods: Reversible addition fragmentation chain transfer polymerization, the Turkevich method and ligand exchange were used to prepare polymer-coated gold nanoparticles. Subsequent in vitro physicochemical and biological characterizations and proteomic analysis were performed. Results: Fluorine-modified polymers reduced the adsorption of complement and other immune-reactive proteins while potentially improving circulatory times and modulating liver toxicity by reducing apolipoprotein E adsorption. Fluorine actively discouraged phagocytosis while encouraging the adsorption of therapeutic targets, CD209 and signaling molecule calreticulin. Conclusion: This study suggests that the addition of fluorine in the surface coating of nanoparticles could lead to improved performance in nanomedicine designed for the intravenous delivery of cargos.

Nanomedicines are based around the delivery of therapies by tiny, nanosized delivery vehicles. This method offers a much better way of specifically targeting life-threatening diseases. For fast delivery, nanomedicines can be injected into the blood (intravenously); however, this often leads to an unwanted and exaggerated immune response. The immune system is activated by proteins in the blood that attach themselves to nanoparticles through various chemical interactions (the protein corona effect). Fluorine is a chemical routinely used in surfactants such as firefighting foam and more recently in molecular imaging and nanoparticles designed for the delivery of therapies aimed at cancer. While fluorine has great potential to improve the cellular uptake of therapies, little is known about whether it can also help camouflage the nanoparticles against the immune system responses. Here, using fluorinated polymer-coated gold nanoparticles, the authors demonstrate that fluorine reduces uptake by immune cells and is highly effective at reducing the binding of immune system-initiating proteins. This work successfully illustrates the rationale for more widespread investigation of fluorine during the development of polymer-coated nanoparticles designed for the intravenous delivery of nanomedicines.

Absolute quantification of a steroid hormone that regulates development in Caenorhabditis elegans.

Under favorable conditions, Caenorhabditis elegans larvae grow into reproductive adults after a series of molting cycles. When environmental conditions are harsh, they arrest as dauer larvae. Dafachronic acid (DA), a C. elegans steroid hormone, is required for reproductive development. Here, we report a mass spectrometry (MS) method for absolute quantitation of DA in C. elegans. The extraction of DA from C. elegans was optimized to achieve a recovery rate of greater than 83%. The MS sensitivity to DA increased 100-fold after carboxyl group derivatization with 2-picolylamine. High-resolution selected ion monitoring (HR-SIM) on a Q-Orbitrap mass spectrometer Q Exactive outperformed targeted-MS2 on the same instrument and selected reaction monitoring (SRM) on a triple-quadrupole mass spectrometer TSQ Quantum Discovery. With a limit of quantification as low as 1 pg of DA, the HR-SIM method enables absolute quantification of endogenous DA during the reproductive development of C. elegans. We found that in wild-type (WT) worms, DA increases from 0.04 ± 0.02 ng/mg protein in the L1 larval stage to 1.21 ± 0.67 ng/mg protein in the L2 larval stage and decreases again after the L3 stage. In comparison, four genetic mutants that have a constitutive dauer-formation phenotype due to disrupted insulin, TGF-ß, or cGMP signaling all have a very low DA level in the L2 stage (below 15% of the WT). These mutants are able to escape the dauer fate and most of them grow into fertile adults when supplied with exogenous DA. Therefore, a DA spike in the L2 stage is critical for the reproductive development of C. elegans.

Two-Stage Total Hip Arthroplasty for Primary Advanced Septic Arthritis of the Hip in Adults.

Background: Comparing the outcomes of debridement and total hip arthroplasty (THA) with antibiotic-loaded spacer implantation and subsequent THA for the treatment of patients affected by primary advanced septic arthritis (SA) of the hip in adults. Methods: All of the 20 patients (20 hips) underwent two-stage surgery. Nine patients were submitted to surgical debridement first and then THA (group 1), while 11 patients were treated with antibiotic-loaded spacer and subsequent THA (group 2). Patients were evaluated based on the recurrence of infection, Harris hip score, visual analogue scale (VAS) pain score, and leg length discrepancy. Results: No cases of infection, deep vein thrombosis, death, and loosening of the hip prosthesis were observed during follow-up. The mean follow-up time was 29.09 ± 10.80 months in group 1 and 28.22 ± 14.80 months in group 2. Before the THA surgery, the mean leg length discrepancy was 2.80 ± 2.03 cm in group 1 and 0.50 ± 0.23 cm in group 2 (P < 0.05). In the latest follow-up, the Harris hip scores of patients were 90.33 ± 4.85 in group 1 and 94.36 ± 2.34 in group 2 (P < 0.05), respectively. There was no statistically significant difference in the VAS pain score of the hip between the two groups (P > 0.05). Conclusions: Debridement and antibiotic-loaded spacer and subsequent THA were effective in eradicating the infection for advanced SA. However, antibiotic-loaded spacer and subsequent THA was superior for effectively maintaining the length of the lower limb and function of the hip.

Sorafenib inhibits ovarian cancer cell proliferation and mobility and induces radiosensitivity by targeting the tumor cell epithelial-mesenchymal transition.

Sorafenib, a pan-protein kinase inhibitor, inhibits the activity of various kinases (like vascular endothelial growth factor, platelet-derived growth factor, and rapidly accelerated fibrosarcoma) and clinically has been used to treat different human cancers. This study investigated its antitumor activity in ovarian cancer and the underlying molecular events. To achieve that, ovarian cancer SKOV-3 cells were treated with or without sorafenib (10 µM), transforming growth factor (TGF)-ß1 (10 ng/mL), sorafenib (10 µM) + TGF-ß1 (10 ng/mL), and TGF-ß1 (10 ng/mL) + Ly2157299 (5 µM), followed by 8-Gy radiation. The cells were then subjected to cell viability, wound healing, Transwell, caspase-3 activity, and western blot assays. TGF-ß1 treatment enhanced ovarian cancer cell epithelial-mesenchymal transition (EMT), whereas sorafenib and a selective TGF-ß1 inhibitor Ly2157299 reversed tumor cell EMT, invasion, and expression of EMT markers (E-cadherin and vimentin). Sorafenib and Ly2157299 treatment also significantly reduced the tumor cell viability. Furthermore, both sorafenib and Ly2157299 significantly enhanced ovarian cancer cell radiosensitivity, as assessed by a caspase-3 activity assay. In conclusion, sorafenib inhibited ovarian cancer cell proliferation and mobility and induced tumor cell radiosensitivity. Molecularly, sorafenib could inhibit the TGF-ß1-mediated EMT. Future studies will assess sorafenib anti-ovarian cancer activity plus TGF-ß1 inhibitors in ovarian cancer in vivo.

Identification of Recurrent Insertions and Deletions in Exon 18 and 19 of Human Epidermal Growth Factor Receptor 2 as Potential Drivers in Non-Small-Cell Lung Cancer and Other Cancer Types.

PURPOSE: Human epidermal growth factor receptor 2 (HER2) belongs to the same family as epidermal growth factor receptor (EGFR) and is known as an important cancer driver gene. Insertions and deletions (indels) are frequent driver mutations in both EGFR and HER2. The most common HER2 indels are the exon 20 insertions within the kinase domain, while others are rarely reported. Our study aimed to investigate other indels of HER2 that may act as driver mutations in Chinese patients with different cancer types. METHODS: In this retrospective study, patient samples were subjected to targeted sequencing covering HER2 and other cancer-related genes. Mutation profiles of patients harboring HER2 exon 18/19 indels were described. Identified HER2 exon 18/19 indels in our study were compared with external data from COSMIC. In silico and in vitro analyses were performed on selected indels of HER2 exon 18 and 19, respectively. RESULTS: A total of 25 indels in HER2 exon 18/19, 17 of which being recurrent, were identified in 20 of 53,591 patients with lung cancer (0.037%), two of 5,888 patients with colorectal cancer (0.034%), two of 3,774 patients with breast cancer (0.053%), and one of 14 patients with urothelial carcinoma of the renal pelvis (7.1%). Most patients harboring HER2 exon 18/19 indels were absent of known driver mutations. In lung cancer, mutation profiles were comparable between patients carrying HER2 exon 18/19 indels and the two established HER2 drivers (exon 20 insertions and S310 mutations). The in silico and in vitro analyses suggested an activated state conferred by HER2 exon 18/19 indels, which could be targeted by different tyrosine kinase inhibitors. CONCLUSION: Our study revealed a class of rare but unique indels in HER2 exon 18/19, which may act as driver mutations in several cancer types.

A study of the mechanism of lncRNA-CR594175 in regulating proliferation and invasion of hepatocellular carcinoma cells in vivo and in vitro.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the cancers of highest incidence and mortality worldwide. The proliferation and invasion of tumor cells are the main reason for poor prognosis after HCC surgery. Long non-coding RNA (lncRNA) has been shown to play a key role in the progression of HCC. LncRNA-CR594175 is one of the highly expressed lncRNAs in HCC tumors and their metastatic tumors that we have obtained by the High-throughput screening method. METHODS: To elucidate the role of lncRNA-CR594175 in regulating the proliferation and invasion of human hepatoma cell line, HepG2, we operated through lncRNA-CR594175 silencing to inhibit the progression of HCC, either through in vitro or in vivo experiments. RESULTS: We found that lncRNA-CR594175 was lower in adjacent non-cancerous tissues than in primary HCC, and was lower in primary HCC than in its metastasis. Silencing of lncRNA-CR594175 inhibited the proliferation and invasion of HepG2 cells and growth of subcutaneous tumors. The results revealed that lncRNA-CR594175, as a RNA sponge, broke the negative regulation of hsa-miR-142-3p on Catenin, beta-1 (CTNNB1), and once lncRNA-CR594175 was silenced, the hsa-miR142-3p regained its negative regulation on CTNNB1 which can promote HCC progression by activating the wnt pathway. CONCLUSIONS: Our present study demonstrated for the first time that lncRNA-CR594175 silencing suppressed proliferation and invasion of HCC cells in vivo and in vitro by restoring the negative regulation of hsa-miR-142-3p on CTNNB1, laying a solid theoretical base for using lncRNA-CR594175 as genetic target therapy for HCC and offering a reasonable explanation for inactivation of miRNA in different tumors or in the tumor at different stages.

Exosome-transmitted miR-567 reverses trastuzumab resistance by inhibiting ATG5 in breast cancer.

Trastuzumab is commonly used in the treatment of human epidermal growth factor receptor-2 positive (HER-2+) breast cancer, but its efficacy is often limited by the emergence of chemoresistance. Recent studies indicate that exosomes act as vehicles for exchange of genetic cargo between heterogeneous populations of tumor cells, engendering a transmitted drug resistance for cancer development and progression. However, the specific contribution of breast cancer-derived exosomes is poorly understood. In this study, publicly available expression profiling data from breast cancer and bioinformatics analyses were used to screen potential miRNAs in trastuzumab resistance. A series of gain- or loss-functional assays were performed to define the function of miR-567 and ATG5 in trastuzumab resistance and autophagy, both in vitro and in vivo. Our results showed that miR-567 was significantly decreased in trastuzumab-resistant patients compared with responding patients. Moreover, miR-567 was also downregulated in trastuzumab-resistant cells compared with parental cells. Overexpression of miR-567 reversed chemoresistance, whereas silence of miR-567 induced trastuzumab resistance, both in vitro and in vivo. In addition, enhanced miR-567 could be packaged into exosomes, incorporated into receipt cells, suppressing autophagy and reversed chemoresistance by targeting ATG5. To conclude, exosomal miR-567 plays a key role in reversing trastuzumab resistance via regulating autophagy, indicating it may be a promising therapeutic target and prognostic indicator for breast cancer patients.