HAX-1 promotes the chemoresistance, invasion, and tumorigenicity of esophageal squamous carcinoma cells

Landscape of NcRNAs involved in drug resistance of breast cancer

Breast cancer (BC) leads to the most amounts of deaths among women. Chemo-, endocrine-, and targeted therapies are the mainstay drug treatments for BC in the clinic. However, drug resistance is a major obstacle for BC patients, and it leads to poor prognosis. Accumulating evidences suggested that noncoding RNAs (ncRNAs) are intricately linked to a wide range of pathological processes, including drug resistance. Till date, the correlation between drug resistance and ncRNAs is not completely understood in BC. Herein, we comprehensively summarized a dysregulated ncRNAs landscape that promotes or inhibits drug resistance in chemo-, endocrine-, and targeted BC therapies. Our review will pave way for the effective management of drug resistance by targeting oncogenic ncRNAs, which, in turn will promote drug sensitivity of BC in the future.

The Role of the Hematopoietic Cell-Specific Protein 1-Associated Protein X-1 in Human Papillomavirus 16 E2-Induced Human Cervical Squamous Carcinoma Cell Apoptosis via a Mitochondria-Dependent Pathway

OBJECTIVES

Human papillomavirus 16 (HPV 16) E2 is a transcriptional regulator that plays a key role in regulating a variety of biological responses. Hematopoietic cell-specific protein 1-related protein X-1 (HAX-1) is a mitochondrial membrane protein, and the HAX-1 gene is involved in the occurrence, growth, invasion, and metastasis of various human malignant tumors. The purpose of this study was to investigate the relationships among HPV 16 E2, the role of HAX-1 gene, and the underlying intracellular apoptotic mechanism of human cervical squamous carcinoma cells (C33a and SiHa).

METHODS

In this study, HAX-1 expression was examined using real-time polymerase chain reaction, Western blot, and immunohistochemical staining analysis. Apoptosis of cells was assessed by flow cytometry. The mitochondrial function was assessed by the mitochondrial copy number, reactive oxygen species (ROS) generation, the mitochondrial membrane potential (ΔΨm), and mitochondrial morphology.

RESULTS

Our study demonstrated that the expression of the HAX-1 gene was significantly increased in human cervical carcinoma tissues relative to noncancerous cervix tissues. HPV 16 E2 inhibited HAX-1 protein expression. Overexpression of HAX-1 increased the mitochondrial copy number, decreased the production of ROS, and maintained the integrity of the mitochondrial membrane and morphology. So, enhanced expression of the HAX-1 gene could abrogate the HPV 16 E2-induced cell apoptosis.

CONCLUSION

Therefore, these data support a mechanism that HAX-1 plays a crucial role in HPV 16 E2-induced human cervical squamous carcinoma cell apoptosis in a mitochondrial-dependent manner.

Germacrone Inhibits Cell Proliferation and Induces Apoptosis in Human Esophageal Squamous Cell Carcinoma Cells

Germacrone, a natural 10-membered monocyclic sesquiterpene with three double bonds and a ketone, was isolated from the roots of traditional Chinese medicine Saussurea costus (SC). The pharmacological value and intrinsic mechanism of germacrone in the treatment of esophageal squamous cell carcinoma (ESCC) are still unclear. Therefore, in this study, we further explored the internal molecular mechanism by which germacrone exerts its antiproliferation and antimigration ability against ESCC. 3-(4,5-Dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assays showed that germacrone dose-dependently inhibited the proliferation of ESCC cells. Flow cytometry analysis (FACS) and wound healing experiments on germacrone treated ESCC cells showed that germacrone could induce apoptosis and inhibit the migration of ESCC cells in a dose-dependent manner. In the study on the mechanism of action of germacrone in antiesophageal cancer, we found that germacrone increased the ratio of Bax/Bcl-2 in the cytoplasm of ESCC, resulting in the activation of Caspase-9 and Caspase-3 and decreased the expression of Grp78, thereby reducing the inhibition of Caspase-12 and Caspase-7. In addition, we found that germacrone also inhibited STAT3 phosphorylation in a dose-dependent manner. In conclusion, we determined that germacrone exerted an antiesophageal effect through intrinsic apoptotic signaling pathways and by inhibiting STAT3 activity in ESCC cells.

HAX1 impact on collective cell migration, cell adhesion, and cell shape is linked to the regulation of actomyosin contractility

HAX1 protein is involved in the regulation of apoptosis, cell motility and calcium homeostasis. Its overexpression was reported in several tumors, including breast cancer. This study demonstrates that HAX1 has an impact on collective, but not single-cell migration, thus indicating the importance of cell–cell contacts for the HAX1-mediated effect. Accordingly, it was shown that HAX1 knockdown affects cell–cell junctions, substrate adhesion, and epithelial cell layer integrity. As demonstrated here, these effects can be attributed to the modulation of actomyosin contractility through changes in RhoA and septin signaling. Additionally, it was shown that HAX1 does not influence invasive potential in the breast cancer cell line, suggesting that its role in breast cancer progression may be linked instead to collective invasion of the epithelial cells but not single-cell dissemination.

Retraction Note: HAX-1 Promotes the Chemoresistance, Invasion, and Tumorigenicity of Esophageal Squamous Carcinoma Cells

The Editor-in-Chief has retracted this article [1] because Figure 3c appears to have been modified and reused as Figure 3d.

Role of the tumour protein P53 gene in human cervical squamous carcinoma cells: Discussing haematopoietic cell-specific protein 1-associated protein X-1-induced survival, migration and proliferation

The haematopoietic cell-specific protein 1-associated protein X-1 (HAX-1), as a mitochondrial membrane protein, induces cancer progression and metastasis. The present study aimed to investigate the role of HAX-1-induced survival, migration and proliferation of human cervical squamous carcinoma cells and to elucidate its potential molecular mechanisms. The level of HAX-1 was examined by quantitative polymerase chain reaction and western blot analyses. The survival, migration and proliferation of the human cervical squamous carcinoma SiHa cell line were measured by the water-soluble tetrazolium salt (WST-1) assay, Transwell assay and ³H-thymidine incorporation into DNA (³H-TdR) assay, respectively. The intracellular reactive oxygen species (ROS) was estimated by the fluorescence of H₂DCFDA, and the mitochondrial membrane potential was tested using a JC-1 probe. The expression of the HAX-1 gene was significantly increased in human cervical carcinoma tissues relative to non-cancerous cervix tissues. Overexpression of HAX-1 increased the survival, migration and proliferation ability of SiHa cells, decreased the production of ROS, and maintained the integrity of the mitochondrial membrane and morphology. The effect brought on these cells could be abrogated by the addition of wild-type tumour protein P53 (p53) or carbonyl cyanide-p-trifluoro methoxyphenylhydrazone-induced mitochondrial dysfunction. In summary, these data support the notion that HAX-1 induced the survival, migration and proliferation of human cervical squamous carcinoma cells by inhibiting its downstream regulatory factor p53 in SiHa cells.

HAX1 is associated with neuronal apoptosis and astrocyte proliferation after spinal cord injury

HS1-associated protein X-1 (HAX1) is a class of multifunctional protein, participated in various physiological processes such as cell apoptosis, proliferation and motility. However, the HAX1 expression and function in the spinal cord injury (SCI) pathological process have not been investigated. In our current research, the rat model of SCI was established, and then we explored the possible role of HAX1 after SCI. The results of western blot indicated that HAX1 was present in sham operated control group and significantly elevated at 3 days post SCI, then declined gradually. Immunohistochemical studies indicated HAX1 expression was enhanced significantly in white and gray matter at 3 days post SCI compared with sham operated group. Double immunofluorescence staining showed the proportion of cells, double-labeled HAX1 and neurons, astrocytes, increased significantly at 3 days post SCI. In addition, co-localization of HAX1/active caspase-3 and HAX1/PCNA was tested in cells. Furthermore, over-expression of HAX1 inhibited neuronal apoptosis in vitro, and in astrocytes HAX1 silencing could down-regulate PCNA expression post LPS treatment. Meanwhile, CCK8 assay showed that knockdown of HAX1 could inhibit the astrocyte proliferation. In summary, our data indicated that HAX1 might play significant roles in pathological process of neuronal apoptosis and astrocyte proliferation during SCI.

Clinical and biological significance of HAX-1 overexpression in nasopharyngeal carcinoma

HS1-associated protein X-1 (HAX-1) is an important marker in many types of cancers and contributes to cancer progression and metastasis. We examined the expression of HAX-1 in nasopharyngeal carcinoma (NPC) and experimentally manipulated its expression. We observed that HAX-1 expression is elevated in NPC and is correlated with lymph node metastasis, M classification, clinical stage, and poor prognosis. In addition, overexpression of HAX-1 promoted NPC proliferation both in vitro and in vivo. Exosomes are potential carriers of pro-tumorigenic factors that participate in oncogenesis. We found that NPC-derived exosomes are enriched in HAX-1 and accelerate NPC tumor growth and angiogenesis in vitro and in vivo. Furthermore, we demonstrated that oncogenic HAX-1 facilitates the growth of NPC when it is transferred via exosomes to recipient human umbilical vein endothelial cells (HUVECs). Oncogenic HAX-1 also increases the proliferation, migration, and angiogenic activity of HUVECs. Our findings provide unique insight into the pathogenesis of NPC and underscore the need to explore novel therapeutic targets such as HAX-1 to improve NPC treatment.

The biology and function of extracellular vesicles in nasopharyngeal carcinoma (Review)

Extracellular vesicles are a heterogeneous group of membrane-enclosed vesicles, which play an important role in intercellular communication. Increasing number of studies have shown that tumor-derived extracellular vesicles might be involved in the transfer of oncogenic cargo (proteins, lipids, messenger RNA, microRNA, non-coding RNAs and DNA) through which cancer cells could shape the tumor microenvironment and influence tumor progression. Nasopharyngeal carcinoma-derived extracellular vesicles have also reported to facilitate tumor proliferation, metastasis and immune escape. Moreover, nasopharyngeal carcinoma-derived extracellular vesicles might serve as biomarkers for early diagnosis and therapeutic targets. The present review provides information on the biological and clinical significance of extracellular vesicles in tumors, especially in nasopharyngeal carcinoma.

Chemoresistance is associated with overexpression of HAX-1, inhibition of which resensitizes drug-resistant breast cancer cells to chemotherapy

Acquired resistance to standard chemotherapy is the common and critical limitation for cancer therapy. Hematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) has been reported to be upregulated in numerous cancers. However, the role of HAX-1 in oncotherapy remains unclear. In this study, we established MDA-MB-231 cell lines which were resistant to cisplatin (MDA-MB-231/CR) or doxorubicin (MDA-MB-231/DR) to study the chemoresistance in breast cancer. As a result, the HAX-1 which is an apoptosis-associated protein was observed to be overexpressed in both MDA-MB-231/CR and MDA-MB-231/DR compared with the routine MDA-MB-231 cells. Moreover, knockdown of HAX-1 via RNA interference decreased IC50 level of cisplatin by 70.91% in MDA-MB-231/CR cells, and the IC50 level of doxorubicin was decreased by 76.46% in MDA-MB-231/DR cells when the HAX-1 was downregulated. Additionally, we found that the knockdown of HAX-1 induced the release of cytochrome C from mitochondria, resulting in the activation of caspases. Taken together, our study indicates that the overexpression of HAX-1 is essential in the development of chemoresistance in breast cancer. Furthermore, we identify that HAX-1 may become the target for cancer therapy.

Silencing of Ribosomal Protein L34 (RPL34) Inhibits the Proliferation and Invasion of Esophageal Cancer Cells

Ribosomal protein L34 (RPL34) belongs to the L34E family of ribosomal proteins and contains a zinc finger motif. Aberrant expression of RPL34 has been reported in several human malignancies. However, the precise role and potential underlying mechanisms of RPL34 in human esophageal cancer remain largely unknown. Thus, the objective of this study was to investigate the role of RPL34 in esophageal cancer progression. Our results showed that the expression of RPL34 at both the mRNA and protein levels was frequently upregulated in esophageal cancer cell lines. Knockdown of RPL34 efficiently inhibited esophageal cancer cell proliferation, migration, and invasion in vitro. Mechanistically, knockdown of RPL34 significantly downregulated the protein expression level of p-PI3K and p-Akt in esophageal cancer cells. Finally, knockdown of RPL34 attenuated tumor growth in nude mice. In conclusion, our study revealed that RPL34 functions as an oncogene that modulates the proliferation and metastasis of esophageal cancer cells, in part, by the inactivation of the PI3K/Akt signaling pathway. Thus, these findings suggest that RPL34 may serve as a potential therapeutic target for the treatment of esophageal cancer.

Expression of HAX-1 in colorectal cancer and its role in cancer cell growth

Colorectal cancer (CRC) is one of the most common types of cancer worldwide. Hematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) has been found to be involved in several types of cancer. However, the role of HAX-1 in CRC remains to be elucidated. The aim of the present study was to investigate whether the expression of HAX-1 is associated with the progression of CRC, and to determine the effects of HAX-1 on the apoptosis and proliferation of CRC cells. Tumor tissues and adjacent noncancerous tissues were collected from 60 patients with CRC, following the provision of informed consent. The expression levels of HAX-1 and the association with clinical and pathological characteristics were then analyzed. The expression levels of HAX-1 were significantly higher in the cancerous tissues from the patients with CRC, particularly in tissues of an advanced stage of cancer. In addition, HAX-1 expression was associated with malignant progression and poor prognosis. Furthermore, SW480 CRC cells, overexpressing HAX-1, exhibited increased resistance to camptothecin in vitro, and promoted proliferation in vitro and in vivo. By contrast, HAX-1 knockdown significantly decreased the proliferation. In addition, the expression levels of ki-67 and phosphorylatedakt were inhibited following HAX-1 knockdown. In conclusion, the expression levels of HAX-1 were increased in cancerous tissue from patients with CRC, and were associated with progression of the disease. These results suggested that HAX-1 may contribute to chemotherapy resistance and malignant progression in CRC.

Biased random walk model for the prioritization of drug resistance associated proteins

Multi-drug resistance is the main cause of treatment failure in cancer patients. How to identify molecules underlying drug resistance from multi-omics data remains a great challenge. Here, we introduce a data biased strategy, ProteinRank, to prioritize drug-resistance associated proteins in cancer cells. First, we identified differentially expressed proteins in Adriamycin and Vincristine resistant gastric cancer cells compared to their parental cells using iTRAQ combined with LC-MS/MS experiments, and then mapped them to human protein-protein interaction network; second, we applied ProteinRank to analyze the whole network and rank proteins similar to known drug resistance related proteins. Cross validations demonstrated a better performance of ProteinRank compared to the method without usage of MS data. Further validations confirmed the altered expressions or activities of several top ranked proteins. Functional study showed PIM3 or CAV1 silencing was sufficient to reverse the drug resistance phenotype. These results indicated ProteinRank could prioritize key proteins related to drug resistance in gastric cancer and provided important clues for cancer research.

Cancer stem cells in oesophageal squamous cell carcinoma: Identification, prognostic and treatment perspectives

Cancer stem cells (CSCs) are a vital subpopulation of cells to target for the treatment of cancers. In oesophageal squamous cell carcinoma (ESCC), there are several markers such as CD44, ALDH, Pygo2, MAML1, Twist1, Musashi1, Side population (SP), CD271 and CD90 that have been proposed to identify the cancer stem cells in individual cancer masses. It has also been demonstrated that stem cell markers like ALDH1, HIWI, Oct3/4, ABCG2, SOX2, SALL4, BMI-1, NANOG, CD133 and podoplanin are associated with patient's prognosis, pathological stages, cancer recurrence and therapy resistance. Finding new cancer stem cell targets or designing drugs to manipulate the known molecular targets in CSCs could be useful for improvements in clinical outcomes of the disease. To conclude, data suggest that CSCs in oesophageal squamous cell carcinoma are related to resistance to therapy and poor prognosis of patients with ESCC. Therefore, innovative insights into CSC biology and CSC-targeted therapies will help to achieve more effective management of patients with oesophageal squamous cell carcinoma.

Expression and Function of HAX-1 in Human Cutaneous Squamous Cell Carcinoma

HAX-1 is an anti-apoptotic factor and overexpressed in many types of cancers. However, the functional role of HAX-1 in human cutaneous squamous cell carcinoma (cSCC) remains unclear. Our aim was to investigate the expression of HAX-1 in cSCC and its relationship with the development of cSCC. HAX-1 expression in cSCC tissues and in-vitro cell models were evaluated by real-time quantitative PCR (RT-qPCR), Western blot and immunohistochemistry. And the RNAi strategy was used to observe the relationship of HAX-1 and cSCC in A431 cells. The mRNA and protein level of HAX-1 were significantly higher in cSCC compared with normal tissue. There were significant differences in thickness (P=0.014), differentiation (P=0.027) and TNM stages (P=0.007). After knockdown the expression of HAX-1 by siRNA, the proliferation and the motility of A431 cell was inhibited obviously, and the apoptosis of A431 cells were induced too. HAX-1 may be a risk factor for patients with cSCC. As a potential tumor promoter in cSCC, HAX-1 may be a novel potential therapeutic target for cSCC treatment and deserves further investigation.

Clinical significance of HAX-1 expression in laryngeal carcinoma

OBJECTIVE

HS1-associated protein X-1 (HAX-1) is a multifunctional protein that has been highlighted as an important marker in many types of cancers. However, little is known about the role of HAX-1 in laryngeal carcinoma. The purpose of the present study is to explore HAX-1 expression status and its associations with clinicopathologic features and survival in a well-defined cohort of laryngeal carcinoma.

METHODS

We examined the expression of HAX-1 at protein and mRNA levels in laryngeal carcinoma tissues and adjacent non-tumor tissues by immunohistochemistry, Western blotting and two-step quantitative real-time PCR analysis, respectively.

RESULTS

We observed that HAX-1 was significantly elevated in laryngeal carcinoma. The relationship between the levels of HAX-1 expression and clinicopathologic characteristics was then analyzed. Overexpression of HAX-1 was significantly correlated with T classification, lymph node metastasis, clinical stage, and pathology. Survival curves were plotted using the Kaplan-Meier method and compared using the log-rank test. We find that patients with overexpression of HAX-1 had shorter overall survival rates. Finally, the significance of various survival variables was analyzed using multivariate Cox proportional hazards model. We found that overexpression of HAX-1 was an independent prognostic factor for patients with laryngeal carcinoma.

CONCLUSION

Our findings hinted that overexpression of HAX-1 was a potentially unfavorable factor in the progression and prognosis of laryngeal carcinoma.

Identification and characterization of OSTL (RNF217) encoding a RING-IBR-RING protein adjacent to a translocation breakpoint involving ETV6 in childhood ALL

Genomic aberrations involving ETV6 on band 12p13 are amongst the most common chromosomal abnormalities in human leukemia. The translocation t(6;12)(q23;13) in a childhood B-cell acute lymphoblastic leukemia (ALL) cell line fuses ETV6 with the putative long non-coding RNA gene STL. Linking STL properties to leukemia has so far been difficult. Here, we describe a novel gene, OSTL (annotated as RNF217 in Genbank), which shares the first exon and a CpG island with STL but is transcribed in the opposite direction. Human RNF217 codes for a highly conserved RING finger protein and is mainly expressed in testis and skeletal muscle with different splice variants. RNF217 shows regulated splicing in B cell development, and is expressed in a number of human B cell leukemia cell lines, primary human chronic myeloid leukemia, acute myeloid leukemia with normal karyotype and acute T-ALL samples. Using a yeast two-hybrid screen, we identified the anti-apoptotic protein HAX1 to interact with RNF217. This interaction could be mapped to the C-terminal RING finger motif of RNF217. We propose that some of the recurring aberrations involving 6q might deregulate the expression of RNF217 and result in imbalanced apoptosis signalling via HAX1, promoting leukemia development.

Hax-1 is required for Rac1-Cortactin interaction and ovarian carcinoma cell migration

Hax-1 is a multifunctional protein, which is involved in diverse cellular signaling pathways including tumor cell survival and migration. We have shown previously that cell migration stimulated by the oncogenic G protein, G_13, requires Hax-1 for the formation of a functional complex involving Gα₁₃, Rac1, and cortactin. However, the role of Hax-1 in cancer cell migration or its role in Rac1-cortactin complex formation, which is known to be required for such migration remains to be characterized. Results focused on resolving the role of Hax-1 in ovarian cancer pathophysiology indicate that Hax-1 is overexpressed in ovarian cancer cells and the silencing of Hax-1 inhibits lysophosphatidic acid (LPA)- or fetal bovine serum-stimulated migration of these cells. In addition, silencing of Hax-1 greatly reduces Rac1-cortactin interaction and their colocalization in SKOV3 cells. Mapping the structural domains of Hax-1 indicates that it interacts with cortactin via domains spanning amino acids 1 to 56 (Hax-D1) and amino acids 113 to 168 (Hax-D3). Much weaker interaction with cortactin was also observed with the region of Hax-1 spanning amino acids 169 – 224 (Hax-D4). Similar mapping of Hax-1 domains involved in Rac1 interaction indicates that it associates with Rac1 via two primary domains spanning amino acids 57 to 112 (Hax-D2) and 169 to 224 (Hax-D4). Furthermore, expression of either of these domains inhibits LPA-mediated migration of SKOV3 cells, possibly through their ability to exert competitive inhibition on endogenous Hax-1-Rac1 and/or Hax-1-cortactin interaction. More significantly, expression of Hax-D4 drastically reduces Rac1-cortactin colocalization in SKOV3 cells along with an attenuation of LPA-stimulated migration. Thus our results presented here describe for the first time that Hax-1 interaction is required for the association between Rac1 and cortactin and that these multiple interactions are required for the LPA-stimulated migration of SKOV3 ovarian cancer cells.

Analysis of HAX-1 gene expression in esophageal squamous cell carcinoma

Objective

To explore the expression of HAX-1 mRNA and protein in esophageal squamous cell carcinoma (ESCC) and its relation with the prognosis of patients with ESCC.

Methods

The expression of HAX-1 mRNA and protein were detected with quantitative real-time RT-PCR and immunohistochemical method in 112 ESCC samples and 112 corresponding non-neoplastic samples. Survival curves were made with follow-up data. The relations of the prognosis with clinical and pathological characteristics were analyzed.

Results

The expression level of HAX-1 mRNA and the strong positive rate of HAX-1 protein were significantly higher in ESCC samples (0.527 ± 0.060 and 45.54%) than that in non-neoplastic samples (0.121 ± 0.017 and 0.00%), and in ESCC samples with lymph node metastasis (0.554 ± 0.054 and 71.11%) than that in ESCC samples without lymph node metastasis (0.509 ± 0.058 and 28.36%) (all P < 0.01). HAX-1 mRNA expression level was a risk factor of lymph node metastasis in patients with ESCC (P = 0.000). There were significant differences in survival curves between lymph node metastatic group and non-metastatic group (P = 0.000), and among groups of HAX-1 protein expression +, ++and +++(,P = 0.000); but no statistical significance between male patients and female patients (P = 0.119), and between ≥60 years old patients and <60 years old patients (P = 0.705). The level of HAX-1 mRNA (P = 0.000) and protein (P = 0.005) were risk factors of survival, but lymph node metastasis (P = 0.477) was not.

Conclusion

There is HAX-1 over-expression in ESCC tissue and HAX-1 mRNA level is a risk factor of lymph node metastasis. The level of HAX-1 mRNA and protein were risk factors of survival in patients with ESCC. HAX-1 may be a novel therapeutic target for ESCC treatment.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5130393079296037