Limits...
Elevated HOXB9 expression promotes differentiation and predicts a favourable outcome in colon adenocarcinoma patients.

Zhan J, Niu M, Wang P, Zhu X, Li S, Song J, He H, Wang Y, Xue L, Fang W, Zhang H - Br. J. Cancer (2014)

Bottom Line: Elevated HOXB9 expression was identified in well-differentiated colon adenocarcinoma patients and was associated with a better overall patients' survival.Overexpression of HOXB9 inhibited colon adenocarcinoma cell growth, migration, invasion in vitro and tumour growth, liver as well as lung metastases in nude mice; whereas silencing HOXB9 promoted these functions.Elevated expression of HOXB9 predicts a longer survival in colon adenocarcinoma patients.

View Article: PubMed Central - PubMed

Affiliation: 1] Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Peking University Health Science Center, Beijing 100191, China [2] State Key Laboratory of Natural and Biomimetic Drugs, Peking University Health Science Center, Beijing 100191, China [3] Laboratory of Molecular Cell Biology and Tumor Biology, Department of Anatomy, Histology and Embryology, Peking University Health Science Center, Beijing 100191, China.

ABSTRACT

Background: Little is known about the tumour suppressive proteins and the underlying mechanisms that suppress colon cancer progression. Homeodomain-containing transcription factor HOXB9 plays an important role in embryogenesis and cancer development. We here aim to uncover the potential role of HOXB9 in the regulation of colon adenocarcinoma progression including epithelial-to-mesenchymal transition.

Methods: HOXB9 expression in colon adenocarcinoma cells and patients was analysed by western blot and immunohistochemistry separately. Correlation between HOXB9 expressions with patients' survival was assessed by Kaplan-Meier analysis. HOXB9-regulated target gene expression was determined by RNA sequencing in HOXB9-overexpressing colon adenocarcinoma cells.

Results: Elevated HOXB9 expression was identified in well-differentiated colon adenocarcinoma patients and was associated with a better overall patients' survival. Overexpression of HOXB9 inhibited colon adenocarcinoma cell growth, migration, invasion in vitro and tumour growth, liver as well as lung metastases in nude mice; whereas silencing HOXB9 promoted these functions. HOXB9 promoted colon adenocarcinoma differentiation via a mechanism that stimulates mesenchymal-to-epithelial transition, involving downregulation of EMT-promoting transcriptional factors including Snail, Twist, FOXC2 and ZEB1 and upregulation of epithelial proteins including E-cadherin, claudins-1, -4, -7, occludin and ZO-1.

Conclusions: HOXB9 is a novel tumour suppressor that inhibits colon adenocarcinoma progression by inducing differentiation. Elevated expression of HOXB9 predicts a longer survival in colon adenocarcinoma patients.

Show MeSH

Related in: MedlinePlus

HOXB9 inhibits colon cancer cell growth, migration and invasion. (A) Cell growth assay. HOXB9 effect on colon adenocarcinoma cell growth was measured using WST-1 method in HCT116 cells stably expressing Flag-HOXB9 or Flag. (B) Gain-of-function experiments. Upper panels: HOXB9 effect on colon adenocarcinoma cell migration was determined in a Transwell assay by comparing HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels), with quantification on the right panel. Lower panels: HOXB9 effect on colon adenocarcinoma cell invasion in Matrigel was examined using HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels). The cell invasion assay was quantified and displayed on the right panel. (C) Loss-of-function experiments. Upper panels: the requirement of HOXB9 in colon adenocarcinoma cell migration was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). The migratory cells were quantified as shown on the right panel. Lower panels: the effect of HOXB9 on colon adenocarcinoma cell invasion was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). Quantification of cell invasion was shown on the right panel. Student's t-tests were applied for analysing the difference between the two cell populations in growth, migration and invasion assays, and in each case the difference was regarded as significant with p⩽0.05.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4150282&req=5

fig3: HOXB9 inhibits colon cancer cell growth, migration and invasion. (A) Cell growth assay. HOXB9 effect on colon adenocarcinoma cell growth was measured using WST-1 method in HCT116 cells stably expressing Flag-HOXB9 or Flag. (B) Gain-of-function experiments. Upper panels: HOXB9 effect on colon adenocarcinoma cell migration was determined in a Transwell assay by comparing HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels), with quantification on the right panel. Lower panels: HOXB9 effect on colon adenocarcinoma cell invasion in Matrigel was examined using HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels). The cell invasion assay was quantified and displayed on the right panel. (C) Loss-of-function experiments. Upper panels: the requirement of HOXB9 in colon adenocarcinoma cell migration was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). The migratory cells were quantified as shown on the right panel. Lower panels: the effect of HOXB9 on colon adenocarcinoma cell invasion was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). Quantification of cell invasion was shown on the right panel. Student's t-tests were applied for analysing the difference between the two cell populations in growth, migration and invasion assays, and in each case the difference was regarded as significant with p⩽0.05.

Mentions: Given that the aforementioned data demonstrated that elevated HOXB9 expression predicts longer colon adenocarcinoma patient survival, suggesting that HOXB9 may play a tumour suppressive role. To this end, we examined the role of HOXB9 in the regulation of colon adenocarcinoma progression. In a gain-of-function experiment, overexpression of HOXB9 in HCT116 cells inhibited cell growth (Figure 3A), migration (Figure 3B upper panels) and invasion on Matrigel (Figure 3B lower panels). In contrast, in a loss-of-function experiment by knocking down the endogenous expression of HOXB9 using small interference RNAs (siRNAs), colon adenocarcinoma cells HCT116 were rescued from the inhibitory effect of HOXB9 and re-gained the capacities for cell migration (Figure 3C upper panels) and invasion (Figure 3C lower panels). These data indicated that the existence of endogenous HOXB9 exerts an important effect that suppresses cell growth, migration and invasion in colon adenocarcinoma.


Elevated HOXB9 expression promotes differentiation and predicts a favourable outcome in colon adenocarcinoma patients.

Zhan J, Niu M, Wang P, Zhu X, Li S, Song J, He H, Wang Y, Xue L, Fang W, Zhang H - Br. J. Cancer (2014)

HOXB9 inhibits colon cancer cell growth, migration and invasion. (A) Cell growth assay. HOXB9 effect on colon adenocarcinoma cell growth was measured using WST-1 method in HCT116 cells stably expressing Flag-HOXB9 or Flag. (B) Gain-of-function experiments. Upper panels: HOXB9 effect on colon adenocarcinoma cell migration was determined in a Transwell assay by comparing HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels), with quantification on the right panel. Lower panels: HOXB9 effect on colon adenocarcinoma cell invasion in Matrigel was examined using HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels). The cell invasion assay was quantified and displayed on the right panel. (C) Loss-of-function experiments. Upper panels: the requirement of HOXB9 in colon adenocarcinoma cell migration was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). The migratory cells were quantified as shown on the right panel. Lower panels: the effect of HOXB9 on colon adenocarcinoma cell invasion was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). Quantification of cell invasion was shown on the right panel. Student's t-tests were applied for analysing the difference between the two cell populations in growth, migration and invasion assays, and in each case the difference was regarded as significant with p⩽0.05.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150282&req=5

fig3: HOXB9 inhibits colon cancer cell growth, migration and invasion. (A) Cell growth assay. HOXB9 effect on colon adenocarcinoma cell growth was measured using WST-1 method in HCT116 cells stably expressing Flag-HOXB9 or Flag. (B) Gain-of-function experiments. Upper panels: HOXB9 effect on colon adenocarcinoma cell migration was determined in a Transwell assay by comparing HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels), with quantification on the right panel. Lower panels: HOXB9 effect on colon adenocarcinoma cell invasion in Matrigel was examined using HCT116 cells stably expressing Flag-HOXB9 or Flag (the left two panels). The cell invasion assay was quantified and displayed on the right panel. (C) Loss-of-function experiments. Upper panels: the requirement of HOXB9 in colon adenocarcinoma cell migration was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). The migratory cells were quantified as shown on the right panel. Lower panels: the effect of HOXB9 on colon adenocarcinoma cell invasion was examined in HCT116 cells transiently transfected with two HOXB9 siRNAs separately, controlled by scramble siRNA (the left three panels). Quantification of cell invasion was shown on the right panel. Student's t-tests were applied for analysing the difference between the two cell populations in growth, migration and invasion assays, and in each case the difference was regarded as significant with p⩽0.05.
Mentions: Given that the aforementioned data demonstrated that elevated HOXB9 expression predicts longer colon adenocarcinoma patient survival, suggesting that HOXB9 may play a tumour suppressive role. To this end, we examined the role of HOXB9 in the regulation of colon adenocarcinoma progression. In a gain-of-function experiment, overexpression of HOXB9 in HCT116 cells inhibited cell growth (Figure 3A), migration (Figure 3B upper panels) and invasion on Matrigel (Figure 3B lower panels). In contrast, in a loss-of-function experiment by knocking down the endogenous expression of HOXB9 using small interference RNAs (siRNAs), colon adenocarcinoma cells HCT116 were rescued from the inhibitory effect of HOXB9 and re-gained the capacities for cell migration (Figure 3C upper panels) and invasion (Figure 3C lower panels). These data indicated that the existence of endogenous HOXB9 exerts an important effect that suppresses cell growth, migration and invasion in colon adenocarcinoma.

Bottom Line: Elevated HOXB9 expression was identified in well-differentiated colon adenocarcinoma patients and was associated with a better overall patients' survival.Overexpression of HOXB9 inhibited colon adenocarcinoma cell growth, migration, invasion in vitro and tumour growth, liver as well as lung metastases in nude mice; whereas silencing HOXB9 promoted these functions.Elevated expression of HOXB9 predicts a longer survival in colon adenocarcinoma patients.

View Article: PubMed Central - PubMed

Affiliation: 1] Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Peking University Health Science Center, Beijing 100191, China [2] State Key Laboratory of Natural and Biomimetic Drugs, Peking University Health Science Center, Beijing 100191, China [3] Laboratory of Molecular Cell Biology and Tumor Biology, Department of Anatomy, Histology and Embryology, Peking University Health Science Center, Beijing 100191, China.

ABSTRACT

Background: Little is known about the tumour suppressive proteins and the underlying mechanisms that suppress colon cancer progression. Homeodomain-containing transcription factor HOXB9 plays an important role in embryogenesis and cancer development. We here aim to uncover the potential role of HOXB9 in the regulation of colon adenocarcinoma progression including epithelial-to-mesenchymal transition.

Methods: HOXB9 expression in colon adenocarcinoma cells and patients was analysed by western blot and immunohistochemistry separately. Correlation between HOXB9 expressions with patients' survival was assessed by Kaplan-Meier analysis. HOXB9-regulated target gene expression was determined by RNA sequencing in HOXB9-overexpressing colon adenocarcinoma cells.

Results: Elevated HOXB9 expression was identified in well-differentiated colon adenocarcinoma patients and was associated with a better overall patients' survival. Overexpression of HOXB9 inhibited colon adenocarcinoma cell growth, migration, invasion in vitro and tumour growth, liver as well as lung metastases in nude mice; whereas silencing HOXB9 promoted these functions. HOXB9 promoted colon adenocarcinoma differentiation via a mechanism that stimulates mesenchymal-to-epithelial transition, involving downregulation of EMT-promoting transcriptional factors including Snail, Twist, FOXC2 and ZEB1 and upregulation of epithelial proteins including E-cadherin, claudins-1, -4, -7, occludin and ZO-1.

Conclusions: HOXB9 is a novel tumour suppressor that inhibits colon adenocarcinoma progression by inducing differentiation. Elevated expression of HOXB9 predicts a longer survival in colon adenocarcinoma patients.

Show MeSH
Related in: MedlinePlus