Characterization of HOX gene expression in canine mammary tumour cell lines from spontaneous tumours

Derivation of a new model of lung adenocarcinoma using canine lung cancer organoids for translational research in pulmonary medicine

Canine primary lung cancer (cPLC) is a rare malignant tumor in dogs, and exhibits poor prognosis. Effective therapeutic drugs against cPLC have not been established yet. Also, cPLC resembles human lung cancer in histopathological characteristics and gene expression profiles and thus could be an important research model for this disease. Three-dimensional organoid culture is known to recapitulate the tissue dynamics in vivo. We, therefore, tried to generate cPLC organoids (cPLCO) for analyzing the profiles of cPLC. After samples from cPLC and the corresponding normal lung tissue were collected, cPLCO were successfully generated, which recapitulated the tissue architecture of cPLC, expressed lung adenocarcinoma marker (TTF1), and exhibited tumorigenesis in vivo. The sensitivity of cPLCO to anti-cancer drugs was different among strains. RNA-sequencing analysis showed significantly upregulated 11 genes in cPLCO compared with canine normal lung organoids (cNLO). Moreover, cPLCO were enriched with the MEK-signaling pathway compared with cNLO. The MEK inhibitor, trametinib decreased the viability of several strains of cPLCO and inhibited the growth of cPLC xenografts. Collectively, our established cPLCO model might be a useful tool for identifying novel biomarkers for cPLC and a new research model for dog and human lung cancer.

Prognostic significance of HOXD4 protein expression in human ovarian cancers

Objectives

Ovarian cancer is the most common gynecological malignancy, ranking as the fifth leading cause of cancer-related deaths among females in the United States. Homeobox D4 (HOXD4) is a transcription factor belonging to the homeobox protein family, which plays a critical role in morphogenesis during embryo development. Here we aimed to study the HOXD4 expression in ovarian serous carcinoma (OSC) and determine its clinical significance.

Materials and Methods

Real-time quantitative PCR and immunohistochemistry targeting human OSC tissues and adjacent ovarian tissues were performed to correlate the patterns of HOXD4 expression with clinical characteristics and survival outcomes. Cell lines and nude mice were used for verifying the role of HOXD4 in OSC.

Results

HOXD4 protein was predominantly expressed in OSC tissues compared with nontumorous tissues. The correlation test demonstrated a significant correlation between HOXD4 with tumor FIGO stage. Univariate and multivariate analyses found that HOXD4 expression was associated with poorer overall survival. Furthermore, high expression of HOXD4 protein was observed in OSC cell lines in vitro. Finally, the oncogenic effect of HOXD4 was confirmed by cellular and xenograft experiments.

Conclusion

HOXD4 protein expression may be associated with a poorer prognosis in OSC. The unfavorable prognostic value of HOXD4 in malignancies and its underlying mechanism are worthy of further investigation.

Autologous hybrid cell fusion vaccine in a spontaneous intermediate model of breast carcinoma

Breast cancer is among the most common malignancies affecting women and reproductively intact female dogs, resulting in death from metastatic disease if not treated effectively. To better manage the disease progression, canine mammary tumor (CMT) cells derived from malignant canine mammary cancers were fused to autologous dendritic cells (DCs) to produce living hybrid-cell fusion vaccines for canine patients diagnosed with spontaneous mammary carcinoma. The high-speed sorting of rare autologous canine patient DCs from the peripheral blood provides the autologous component of fusion vaccines, and fusion to major histocompatibility complex-unmatched CMT cells were produced at high rates. The vaccinations were delivered to each patient following a surgical resection 3 times at 3-week intervals in combination with immuno-stimulatory oligonucleotides and Gemcitabine adjunct therapy. The immunized patient animals survived 3.3-times longer (median survival 611 days) than the control patients (median survival 184 days) and also appeared to exhibit an enhanced quality of life. A comparison of vaccinated patients diagnosed with inflammatory mammary carcinoma resulted in a very short median survival (42 days), suggesting no effect of vaccination. The data showed that the development of autologous living DC-based vaccine strategies in patient animals designed to improve the management of canine mammary carcinoma can be successful and may allow an identification of the antigens that can be translatable to promote effective immunity in canine and human patients.

Evidence for an oncogenic role of HOXC6 in human non-small cell lung cancer

Background

Identification of specific biomarkers is important for the diagnosis and treatment of non-small cell lung cancer (NSCLC). HOXC6 is a homeodomain-containing transcription factor that is highly expressed in several human cancers; however, its role in NSCLC remains unknown.

Methods

The expression and protein levels of HOXC6 were assessed in NSCLC tissue samples by Quantitative real-time PCR (qRT-PCR) and immunohistochemistry, respectively. HOXC6 was transfected into the NSCLC cell lines A549 and PC9, and used to investigate its effect on proliferation, migration, and invasion using CFSE, wound healing, and Matrigel invasion assays. Next-generation sequencing was also used to identify downstream targets of HOXC6 and to gain insights into the molecular mechanisms underlying its biological function.

Results

HOXC6 expression was significantly increased in 66.6% (20/30) of NSCLC tumor samples in comparison to normal controls. HOXC6 promoted proliferation, migration, and invasion of NSCLC cells in vitro. RNA-seq analysis demonstrated the upregulation of 310 and 112 genes in A549-HOXC6 and PC9-HOXC6 cells, respectively, and the downregulation of 665 and 385 genes in A549-HOXC6 and PC9-HOXC6 cells, respectively. HOXC6 was also found to regulate the expression of genes such as CEACAM6, SPARC, WNT6, CST1, MMP2, and KRT13, which have documented pro-tumorigenic functions.

Discussion

HOXC6 is highly expressed in NSCLC, and it may enhance lung cancer progression by regulating the expression of pro-tumorigenic genes involved in proliferation, migration, and invasion. Our study highlighted the oncogenic potential of HOXC6, and suggests that it may be a novel biomarker for the diagnosis and treatment of NSCLC.

Clinicopathological analysis of HOXD4 expression in diffuse gliomas and its correlation with IDH mutations and 1p/19q co-deletion

Backgrounds

HOX (homologous box) is known as the dominant gene of vertebrate growth and cell differentiation. Abnormal expression of HOX gene in various tumors has attracted the attention of scholars. As a component of HOX clusters, HOXD4 plays a controversial role in the tumorigenesis of central nervous system.

Results

The data demonstrated that and the results demonstrated that HOXD4 was overexpressed in glioma tissues compared to that of normal brain tissues. patients with high HOXD4 expression had a significant shorter survival than those with low HOXD4 expression in total glioma cohort (p<0.001), WHO Grade II cohort (p=0.003) and Grade III cohort (p<0.001), but not in Grade IV cohort when OS (overall survival) was analyzed (p=0.216). The findings were confirmed by the large-scale omics data analysis including lower-grade glioma (LGG) and glioblastoma multiforme (GBM) in TCGA (the cancer genome atlas) and CGGA (Chinese glioma genome atlas). Moreover, it was revealed that the expression of HOXD4 have a significant impact on the OS of Grade IV glioma with IDH wild-type and 1p/19q intact according to TCGA data.

Methods

Clinicopathological analysis of HOXD4 expression in 453 glioma patients was performed in the current study. Expression of HOXD4 was evaluated by qPCR and immunohistochemical (IHC) staining. Univariate and multivariate analysis were conducted to investigate the prognostic role of HOXD4 in glioma patients.

Conclusions

Expression of HOXD4 was closely related to the clinical outcomes of patients with gliomas, and HOXD4 may be a potential prognostic biomarker of gliomas.

Homeobox C9 suppresses Beclin1-mediated autophagy in glioblastoma by directly inhibiting the transcription of death-associated protein kinase 1

BACKGROUND

The transcription factor homeobox C9 (HOXC9) plays a crucial role in developmental regulatory systems, where it determines the specific positional identities of cells along the anteroposterior axis. The expression of HOXC9 has been found to be dysregulated in some cancers such as lung cancer, breast cancer, and neuroblastoma. Here, we report for the first time that HOXC9 is a novel autophagy regulator and reveal its oncogenic role in cell survival and its usefulness as a prognostic marker in glioblastoma patients.

METHODS

Kaplan-Meier analysis was performed to evaluate the possible prognostic value of HOXC9 in glioblastoma. Growth curve assays, subcutaneous, and orthotopic implantations were used to analyze cell viability and tumor formation, respectively. Luciferase and chromatin immunoprecipitation assays were employed to explore the mechanisms involved in the association between HOXC9 and its downstream effector, death-associated protein kinase 1 (DAPK1).

RESULTS

High expression of HOXC9 was found to be an indicator of a poor prognosis in glioblastoma. HOXC9 knockdown resulted in a significant reduction of cell viability, migration, invasion, and tumorigenicity and a marked increase in autophagy. During the autophagy process, HOXC9 inhibited DAPK1 transcription by directly binding to its promoter. The downregulation of HOXC9 releases its transcriptional inhibition of DAPK1, resulting in the activation of the DAPK1-Beclin1 pathway, which induces autophagy in glioblastoma cells.

CONCLUSIONS

Collectively, our data indicate that HOXC9 is an oncogene in glioblastoma. We have revealed its role in the control of autophagy, and we suggest that HOXC9 is a novel and promising therapeutic target.

Cis-eQTL analysis and functional validation of candidate susceptibility genes for high-grade serous ovarian cancer

Genome-wide association studies have reported 11 regions conferring risk of high-grade serous epithelial ovarian cancer (HGSOC). Expression quantitative trait locus (eQTL) analyses can identify candidate susceptibility genes at risk loci. Here we evaluate cis-eQTL associations at 47 regions associated with HGSOC risk (P≤10(-5)). For three cis-eQTL associations (P<1.4 × 10(-3), FDR<0.05) at 1p36 (CDC42), 1p34 (CDCA8) and 2q31 (HOXD9), we evaluate the functional role of each candidate by perturbing expression of each gene in HGSOC precursor cells. Overexpression of HOXD9 increases anchorage-independent growth, shortens population-doubling time and reduces contact inhibition. Chromosome conformation capture identifies an interaction between rs2857532 and the HOXD9 promoter, suggesting this SNP is a leading causal variant. Transcriptomic profiling after HOXD9 overexpression reveals enrichment of HGSOC risk variants within HOXD9 target genes (P=6 × 10(-10) for risk variants (P<10(-4)) within 10 kb of a HOXD9 target gene in ovarian cells), suggesting a broader role for this network in genetic susceptibility to HGSOC.