The Role of PPP2R2B in Pancreatic Cancer Progression: A Novel Pro-Cancer Factor

doi:10.21203/rs.3.rs-5324510/v1

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The Role of PPP2R2B in Pancreatic Cancer Progression: A Novel Pro-Cancer Factor

https://doi.org/10.21203/rs.3.rs-5324510/v1

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Pancreatic cancer (PC) is one of the most lethal types of cancer, as current treatments are largely ineffective. Our research uncovers that PPP2R2B is overexpressed in a majority of PC cases, playing a significant role in the growth and spread of PC tumors. Further analysis showed that reducing PPP2R2B levels in PC inactivates the MAPK pathways—ERK, JNK, and p38—impacting epithelial-mesenchymal transition (EMT) and apoptosis processes, ultimately promoting PC growth. Our experiments in live subjects demonstrate that removing PPP2R2B inhibits tumor growth in PC mouse models and alters the levels of proteins involved in EMT and cell death. Thus, our work highlights the crucial role of PPP2R2B as a new factor that promotes cancer progression by influencing EMT and cell death through the MAPK pathway in pancreatic cancer.

Pancreatic cancer

PPP2R2B

MAPK pathway

EMT

Apoptosis

PPP2R2B is overexpressed in a majority of pancreatic cancer (PC) cases, playing a significant role in inhibiting the growth and spread of PC tumors.
PPP2R2B activates the MAPK pathways—ERK, JNK, and p38—impacting epithelial-mesenchymal transition and apoptosis processes, ultimately promoting PC growth.
This work highlights the crucial role of PPP2R2B as a new factor that promotes cancer progression by influencing EMT and apoptosis through the MAPK pathway in PC.

Pancreatic cancer (PC) ranks as the third primary cause of cancer-related fatalities across the globe, known for its aggressive nature and tendency for late detection. This results in a high annual mortality rate of around 400,000 globally. Patients with advanced or inoperable PC have a five-year survival rate of approximately 13%, dropping to 3% for those with distant metastasis [1,2]. Despite improvements in treatment approaches in recent years, the delayed diagnosis often limits the potential for surgical resection as a curative option [3,4]. Therefore, a comprehensive comprehension of the biological processes behind PC is fundamental for the creation of more potent biomarkers and treatment strategies.

PPP2R2B, part of the B family of regulatory subunit 2 phosphatases, encodes the beta version of the B55 subfamily. Its expression peaks during the fetal stage and decreases as development advances. Predominantly found in the brain and testes, lower levels are present in the lungs and spleen [5,6]. The upregulation of PPP2R2B during neural maturation in embryos highlights its crucial role in embryonic growth. In the realm of cancer, PPP2R2B might carry out functions akin to those seen in development or differentiation [7–11]. While PPP2R2B has been implicated in the initiation and progression of multiple cancers via mutations or elevated expression, its specific effects on prostate cancer growth and metastasis remain to be fully elucidated.

The transition from epithelial to mesenchymal cells (EMT) is a crucial event in the advancement and dissemination of cancer, encompassing a sequence of complex and dynamic stages. It involves a complex series of steps that are dynamic in nature. Among the different pathways involved in EMT [12–14], the Mitogen-Activated Protein Kinase (MAPK) pathway is particularly significant in regulating important cellular processes that contribute to the growth and dissemination of tumors [15,16]. Consequently, targeting the MAPK/EMT axis has emerged as a central focus in contemporary cancer research [17–20]. Our study uncovers a new finding of PPP2R2B being overexpressed in the majority of pancreatic cancer cases, highlighting its essential function in promoting tumor growth and dissemination. In addition, our findings illustrate the capability of PPP2R2B to stimulate the proliferation and metastasis of PC cells through the MAPK/EMT pathway.

The purpose of this research is to decipher the role of PPP2R2B, a recently identified factor promoting cancer growth, in regulating EMT and apoptosis through the MAPK pathway in driving the advancement of pancreatic cancer. With the limited options for treating PC, our findings may pave the way for innovative treatment approaches focused on inhibiting PPP2R2B.

Data and resources

The Cancer Genome Atlas (TCGA) data repository (https://gdc-portal.nci.nih.gov/) was utilized to access level-three transcriptome RNA sequencing data of patients with PC. In addition, RNA-sequence information from both normal and PC samples was obtained from Datasets GSE62165 and GSE15471 retrieved from the Gene Expression Omnibus (GEO) database (https://www.ncbi.nlm.nih.gov/geo/). The potential prognostic significance of PPP2R2B in PC was investigated using the Gene Expression Profiling Interactive Analysis (GEPIA2) tool (http://gepia.cancer-pku.cn/), a web-based server for customizable and interactive large-scale expression analysis.

Functional enrichment analysis

The deeper exploration of potential functional implications of PPP2R2B associated with PC involved the application of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Moreover, Gene Set Enrichment Analysis (GSEA) was employed to assess the intrinsic molecular mechanisms distinguishing low- and high-risk cohorts.

Patients and samples

Between 2021 and 2022, a total of 60 pairs of tissue samples from PCs and nearby tissues were gathered from individuals who underwent pancreaticoduodenectomy at the First Hospital of Lanzhou University. Prior to participating in the research, all subjects had given their consent after being informed about the study's objectives. Approval for the research was granted by the Ethics Committee at the First Hospital of Lanzhou University (LDYYLL-2024-244).

Cell lines and cell culture

Human four PC cell lines including PANC-1, BxPC-3, SW1990, AsPC-1, and the HPDE6-C7 normal human pancreatic duct epithelial cell line were acquired from the BNCC and the Shanghai Branch of the Chinese Academy of Sciences. In order to ensure cell survival, all cell lines were grown in DMEM at 37°C with 95% humidity and 5% CO₂.

Quantitative real-time PCR (qRT-PCR)

After total RNA extraction with the TRIzol Reagent (TaKaRa), cDNA synthesis was carried out using 5 µg of the mentioned total RNA and the PrimeScript RT Reagent Kit (TaKaRa). A Bio-Rad RT-PCR amplification system along with a SYBR Green PCR Kit (Takara) was utilized for qRT-PCR. The quantification of mRNA expression levels was conducted using the 2ΔΔCt method, with normalization to the endogenous reference gene GAPDH. The PCR primer sequences for the human PPP2R2B were as follows: (forward) 5′-TGCAGCTTACTTTCTTCTGTCT-3′ and (reverse) 5′-GTAGCCTTCTGGCCTCTTATC-3′. For the GAPDH primers, the sequences were (forward) 5′-AAGGTGAAGGTCGGAGTCAAC-3′ and (reverse) 5′-GGGGTCATTGATGGCAACAATA-3′.

Western blotting (WB)

Antibodies against PPP2R2B, N-cadherin (N-cad), E-cadherin (E-cad), Vimentin, Bax, and Bcl-2 were bought from Wuhan Sanying (Wuhan, China). ERK, JNK and p38 antibodies, were sourced from Boser Bio (Wuhan, China).

Proteins were extracted from cells and tissues using SDS-PAGE gels for separation. Following separation, the proteins were transferred onto a PVDF membrane and then incubated with primary antibodies targeting PPP2R2B, accompanying biomarkers, and GAPDH at 4 degrees Celsius for 48 hours. After blocking the membrane with BSA at room temperature for 2 hours, secondary antibodies were added and incubated for another 2 hours. The membrane underwent three TBST washes before exposure to a luminescent solution, using GAPDH as an internal control.

Immunohistochemistry (IHC) staining

A senior pathologist reviewed tissue slides to detect and label tumor regions. Cylinder replicas (1.0 mm wide) were collected from the designated tumor sites and adjacent non-malignant pancreatic tissue in the donor's tissue samples. These samples were then embedded in a fresh paraffin block. Standard protocols were followed for immunohistochemical staining, employing specific Vimentin, Beclin, and PPP2R2B antibodies.

Cell counting Kit‑8 (CCK-8) assay

Cells were first plated onto 96-well culture dishes with a concentration of 5 × 10³ cells per well. Following plating, the dishes were placed in the incubator for durations spanning from 24 to 72 hours. A CCK-8 solution obtained from Boster Bio (China) was utilized for the experiment. A volume of 10 µL of the CCK-8 solution was added to each separate well and permitted to incubate within the incubator for a duration of one hour. In order to guarantee precise evaluation of cellular growth, the absorbance at a wavelength of 450 nm was measured for each well utilizing a plate reader.

5-Ethynyl-2’-deoxyuridine (EdU) assay

The Seville Biotech (Wuhan, China) provided the necessary reagents for the EdU assay. Pancreatic cancer cells were seeded in confocal dishes at a density of 3×10⁵ cells per well. Subsequently, the cells were treated with 4% paraformaldehyde (Beyotime, China) for 10 minutes to fix them. After fixing, the cells underwent three washes with PBS and were permeabilized for 5 minutes using 1% Triton (Beyotime, China). Subsequently, the cells were exposed to the dyeing agent in the dark for 30 minutes, then subjected to DAPI staining (Olympus, Tokyo, Japan) at 37°C for 5 minutes. Imaging was carried out with a microscope at 400× magnification.

Wound healing assay

An exact count of cells were uniformly spread in a 6-well dish and cultured for a duration of 24 hours. A gap was created between the cells by drawing a single line using the tip of a crystal pipette. After washing with PBS, images were captured; then, drug-containing and standard media were added. Gap growth was monitored and captured at 0 and 24 hours. The area was determined by dividing the width by the length. Mobility of cells (%) was calculated as 100 times the difference in width between 0 h and 24 h, divided by the width at 0 h. The Image J program was utilized to gauge the gap between the opposing ends of the wound. Analysis of the data from three distinct trials involving two sets of samples was conducted for statistical purposes.

Migration and invasion assay

The Transwell system filter (8.0 µm pore size; BD Biosciences, USA) was used for the migration assay. In a 24-well culture plate (Corning, USA), 200 µL of either treated or untreated 1×10⁵ cells were added to the upper chamber of Transwell inserts for 24 hours, followed by the addition of 700 µL of medium containing 30% FBS to the lower chamber. The invasion assay utilized chambers with inserts coated uniformly with Matrigel (BD Biosciences). The chambers were then fixed with 4% paraformaldehyde for 15 minutes and stained with 0.1% crystal violet for 30 minutes. Following this, the upper surface of the inserts was carefully cleaned using absorbent paper, and the stained cells were imaged randomly using a microscope after rinsing with PBS. Cell migration and invasion capabilities were assessed by quantifying the average number of labeled cells across five different fields. Statistical analysis was performed utilizing data from two groups across three independent experiments.

Animal experiment

Four to six-week-old BALB/c mice, weighing between eighteen and twenty grams, were kept in a sterile setting with unrestricted access to food and water. Through unbiased randomization, ten mice were evenly split into two groups, with each group consisting of five mice. Then, both groups were injected subcutaneously in the side with 5×10⁶ PANC-1 cells that expressed various PPP2R2B shRNAs and control NC shRNAs. Weekly measurements were taken of the tumor's dimensions, which were determined using the formula of multiplying the length by the square of the width, and then multiplying by 0.5. Afterward, the mice were put to sleep with isoflurane overdose, followed by measuring the tumor’s size and weight in a lab setting. All animal experiments were conducted in accordance with the Guidelines for the Care and Use of Laboratory Animals, and were granted approval by the Ethics Committee at the First Hospital of Lanzhou University (LDYYLL-2024-244).

Statistical analysis

Statistical analyses were conducted using the SPSS 22.0 software from Chicago, USA, and GraphPad Prism software version 9.5 from the USA. The results were presented as mean ± SEM (standard error of the mean). A comparison of means between two groups was made using an unpaired t-test. To assess differences between two or more groups, one-way ANOVA and the Bonferroni test for multiple comparisons were applied. Statistical significance was defined as p < 0.05.

PPP2R2B's increased expression is observed in human PC cell lines and tissues

Our previous RNA sequencing (RNA-seq) study revealed a significant down-regulation of PPP2R2B in PANC-1 cells upon treatment with a tumor suppressor drug. Furthermore, PPP2R2B is found to be highly expressed in PC samples from both the Cancer Genome Atlas (TCGA) and GEPIA datasets. In this research, we used qRT-PCR to assess the PPP2R2B expression in human PC tissues. The findings indicated a notable rise in PPP2R2B levels in PC tissues in contrast to nearby normal samples. (Fig. 1E). Additionally, the upregulation of PPP2R2B was observed in four PC cell lines (PANC-1, BxPC-3, SW1990, and AsPC-1) in comparison to HPDE6-C7 cells (Fig. 1D). The Kaplan-Meier analysis revealed that patients with PC who exhibited high levels of PPP2R2B had reduced disease-free survival rates in comparison to individuals with low PPP2R2B expression levels ( Fig. 1C). These results indicate that the elevated presence of PPP2R2B could potentially contribute significantly to the progression of PC.

Correlation of PPP2R2B expression with clinical and pathological characteristics

To assess the potential therapeutic relevance of PPP2R2B expression in prostate cancer (PC) patients, we investigated its levels in a cohort of 60 subjects, with a median age of 61. The accompanying table outlines the important clinical, pathological, and radiographic findings in this study population. It is noteworthy that a majority of the tumors (76.7%) examined in our investigation were categorized as stage I-II, with sizes ranging from 2 to 4 cm. As PPP2R2B demonstrates variable expression levels in this PC group, we proceeded to investigate its connection with established tumor traits and indicators of prognosis. Our findings found a correlation between PPP2R2B expression and nerve invasion as well as tumor dimensions. Notably, there was no significant relationship observed between the immunohistochemical score of PPP2R2B and tumor stage or nodal status (refer to Table 1,2).

Table 1

Association between the expression of PPP2R2B in pancreatic cancer and adjacent tissues and clinical characteristics in 60 PC patients
Variables	n(%)	GENE low	GENE high	p Value
Variables	n(%)	expression n(%)	expression n(%)	p Value
Age	60	13	47
< 65	39(65.0)	10(76.9)	29 (61.7)	0.49
≥ 65	21(35.0)	3(23.1)	18(38.3)
Gender
Female	40(66.7)	7(53.8)	33(70.2)	0.438
Male	20(33.3)	6(46.2)	14(29.8)
Primarysite
Pancreatic head	46(76.7)	12(92.3)	34(72.3)	0.256
Pancreatic body tail	14 (23.3)	1(7.7)	13(27.7)
AJCC stage
I,II	46(76.7)	10(76.9)	36(76.6)	l
II,IV	14(23.3)	3(23.1)	11(23.4)
Vascular invasion
No	42(70.0)	9(69.2)	33(70.2)	1
Yes	18(30.0)	4(30.8)	14(29.8)
Nerve invasion
No	18(30.0)	8(61.5)	10(21.3)	0.014
Yes	42(70.0)	5(38.5)	37(78.7)
Lymph node metastasis
No	30 (50.0)	7(53.8)	23(48.9)	1
Yes	30(50.0)	6(46.2)	24(51.1)
Tumor size(cm)
≤ 2	9(15.0)	6(46.2)	3(6.4)	0.002
2–4	36(60.0)	5(38.5)	31(66.0)
≥ 4	15(25.0)	2(15.4)	13(27.7)

Table 2

Spearman analysis between PPP2R2B expression and clinical characteristics in 60 PC patients
Variables	PPP2R2B expression
Variables	Spearman correlation	p Value
Age	0.131	0.317
Gender	-0.143	0.276
Primary site	0.194	0.136
AJCC stage	0.003	0.981
Vascular invasion	-0.009	0.947
Nerve invasion	0.362	0.004
Lymph node metastasis	0.04	0.759
Tumor size	0.328	0.01

The inhibition of PPP2R2B inhibit the proliferation, migration, and invasion of PC cells

Previous studies utilizing qRT-PCR revealed elevated PPP2R2B expression notable in both PANC-1 and BxPC-3 cells (Fig. 1). Based on these results, we selected these two cell lines for further investigations. To study the impact of PPP2R2B on PC development, we established stable knockdown cell lines named sh-PPP2R2B in BxPC-3 and PANC-1 cells (Fig. 2A, B). From the qRT-PCR data, sh-PPP2R2B-2 and sh-PPP2R2B-3 were chosen for subsequent experiments. Following this, we evaluated the growth of PC cells using CCK8 and EdU assays, which indicated that inhibiting PPP2R2B resulted in decreased proliferation of PANC-1 and BxPC-3 cells (Fig. 2B, C). We also examined the impact of PPP2R2B on cell migration and invasion. Our wound healing assays revealed a notable decrease in PC cell motility upon PPP2R2B silencing (Fig. 2D). Migration and invasion capabilities were further assessed using Transwell assays, showing reduced activity in both processes following PPP2R2B knockdown (Fig. 2E). Moreover, upregulating PPP2R2B resulted in heightened cell proliferation, mobility, and infiltration in pancreatic cancer cells, including PANC-1 and BxPC-3 cells(Fig. 3). These results collectively demonstrate that manipulating PPP2R2B expression can modulate the proliferation, migration, and invasion of PC cells.

PPP2R2B knockdown inhibited the MAPK/EMT signaling pathway activity in PC

Further investigation into the role of PPP2R2B in pancreatic cancer was conducted. Analysis of GO and KEGG pathways indicated enrichment of PPP2R2B in the MAPK signaling pathway. Results from GSEA showed a positive correlation between elevated PPP2R2B levels and MAPK pathway activation. PPP2R2B was discovered as a potential activator of the MAPK signaling pathway, which is recognized to impact both EMT and apoptosis, ultimately having a crucial impact on the growth, movement, and infiltration of pancreatic cancer cells. Based on WB examination of EMT markers, it was observed that reducing PPP2R2B resulted in heightened expression of E-cad and reduced levels of N-cad and Vimentin. These findings suggest that PPP2R2B can promote EMT in pancreatic cancer cells. Furthermore, the impact of PPP2R2B on the ERK, JNK, and p38 MAPK pathways was evaluated. WB analysis demonstrated significantly higher levels of ERK, JNK, and p38 in the PPP2R2B knockdown group compared to the sh-NC group (Fig. 4D). These results highlight the role of PPP2R2B in modulating MAPK signaling pathways in pancreatic cancer. Overexpression of PPP2R2B had the opposite effect on MAPK/EMT pathway (Fig. 4E). Overall, activation of PPP2R2B enhances the activity of PC cells through MAPK signaling, promoting their proliferation, migration, invasion, and EMT.

PPP2R2B stimulated PC tumor growth in vivo

To explore the effects of PPP2R2B on the progression of PC, BALB/c mice were injected with PANC-1 cells in which PPP2R2B was either silenced or expressed as a negative control. After 28 days, the tumors were removed and observed. Our results indicated a notable decrease in the size, volume, and weight of tumors in the mice injected with sh-PPP2R2B compared to those in the control group (Fig. 5A). Immunohistochemical studies revealed reduced levels of markers associated with EMT and apoptosis in the sh-PPP2R2B group as opposed to the control, consistent with previous western blot findings. The inhibition of tumor growth in vivo following PPP2R2B knockdown can be seen in Fig. 5.

In the present research, we uncover a new role that promotes tumor growth for PPP2R2B in the advancement of PC. Our results show that PPP2R2B is upregulated in PC cell lines and tumor samples in comparison to normal pancreatic cells and neighboring non-tumor tissues, respectively. Increased PPP2R2B levels are associated with reduced disease-free survival in PC patients, highlighting its potential as a predictive marker. Significantly, we demonstrate that PPP2R2B enhances PC cell growth, movement, and infiltration by modulating the MAPK/EMT signaling pathway, representing a notable advancement in comprehending the molecular characteristics of PC.

The functional implications of PPP2R2B in normal and abnormal states pose an interesting contradiction. Although its involvement in fetal development emphasizes its crucial function in early human growth, particularly in the brain and reproductive system [21], PPP2R2B's reappearance in cancer brings attention to a more sinister aspect of its role [8, 22, 23]. This dual functionality is prominently displayed in the setting of PC, where PPP2R2B appears to revert to its developmental functions, leading to abnormal cell differentiation and proliferation.

Our research suggests that knocking down PPP2R2B in PC cells results in decreased cell proliferation, migration, and invasion capabilities, as demonstrated by CCK-8, EdU, wound healing, and transwell assays. Conversely, upregulating PPP2R2B enhances these malignant characteristics, further supporting its role in promoting tumorigenesis. In animal studies, the tumor-suppressive effects of PPP2R2B depletion were confirmed. Mouse xenografts injected with PC cells lacking PPP2R2B showed significantly inhibited tumor growth compared to control cells. In line with our lab findings, tumors originating from PPP2R2B-deficient cells displayed decreased expression of EMT-triggering and anti-apoptotic markers, further highlighting PPP2R2B's involvement in regulating these processes.

Extensive research has focused on the MAPK/EMT signaling pathway in various cancer types [24,25]. The MAPK/EMT system plays a key role in numerous biological processes, serving as a vital cell signaling pathway [26–28]. These functions encompass embryonic development, tissue regeneration, cell division, and motility. EMT is indispensable for the invasion and metastasis of malignant tumors [29–31]. The activation of the MAPK pathway can trigger EMT, prompting cancer cells to relocate and acquire invasive capabilities [32,33]. By inducing changes in cellular structure and function, EMT facilitates distant organ metastasis and enhances the ability of tumor cells to traverse vascular barriers and access the circulatory or lymphatic systems.

Our research outlines the detailed mechanisms by which PPP2R2B contributes to its oncogenic effects, specifically by influencing the ERK, JNK, and p38 branches of the MAPK signaling pathway to regulate processes related to EMT and apoptosis. In particular, The inhibition of PPP2R2B leads to a decrease in the expression of the epithelial marker E-cad and an increase in the expression of the mesenchymal markers N-cad and Vimentin, suggesting a promotion of the EMT transition process. Furthermore, knockdown of PPP2R2B leads to the promotion of apoptosis, characterized by a increase in pro-apoptotic markers such as Bax and Beclin, and an decrease in the levels of the anti-apoptotic protein Bcl-2.

By analyzing clinical data, a strong correlation was discovered between elevated PPP2R2B levels and nerve infiltration. Prior research has indicated that abnormal PPP2R2B methylation levels play a crucial role in neurological conditions like Spinocerebellar Ataxia Type 12 [22,34]. PPP2R2B has the ability to modify mitochondrial division/fusion patterns by modulating kinase/phosphatase equilibrium, apoptotic and anti-apoptotic protein levels, ultimately leading to neurotoxicity and prompting neuronal demise [35]. Suppression of gene activity exhibits a neuroprotective impact, aligning with our observation that heightened PPP2R2B expression in tumors could hasten nerve cell differentiation and spread.

Through our research into the role of PPP2R2B in the progression of PC, we have uncovered the intricate interplay between genetic factors and the pathways that promote cancer growth. Our findings emphasize PPP2R2B's pivotal function in promoting the spread and growth of tumors. This study demonstrates how PPP2R2B influences the signaling pathway MAPK/EMT, providing new perspectives on the molecular processes driving the advancement of PC.

Furthermore, due to the intricate nature of cancer development, it is crucial to thoroughly explore the interplay between PPP2R2B and various signaling molecules and pathways within the tumor microenvironment. These investigations have the potential to unveil further levels of control and reveal innovative treatment strategies that could potentially counteract resistance mechanisms and improve treatment efficacy.

In summary, our research makes a substantial contribution to the increasing evidence highlighting the crucial importance of PPP2R2B in the development of pancreatic cancer. By elucidating how PPP2R2B impacts the MAPK/EMT signaling pathway and the progression of tumors, we set the stage for additional studies on therapies targeting PPP2R2B that may bring renewed optimism to individuals with pancreatic cancer. As we delve deeper into the complex role of PPP2R2B in cancer, the potential for developing improved and specialized treatments for pancreatic cancer, as well as other types of cancer, appears to be increasingly optimistic.

Conflict of Interest:

None declared.

Ethical Statement

Approval for the research was granted by the Ethics Committee at the First Hospital of Lanzhou University (LDYYLL-2024-244).

Funding

This project was supported by National Natural Science Foundation of China (82260555), The First Hospital of Lanzhou University Intra-Hospital Fund (ldyyyn2020-93), Lanzhou University Student Innovation and Entrepreneurship Action Plan (20220060123).

Author Contribution

Study concepts: FFH, WCZ; Study design: FFH, ZC; Experimental studies: CY, HQS; Data analysis: HQS, ZC; Statistical analysis: FFH, YD; Manuscript preparation: FFH, CLD; Manuscript editing: FFH, PFX; Manuscript review: FFH, WCZ. All authors contributed to the article and approved the submitted version.

Acknowledgements:

Not applicable.

Data availability

Not applicable.

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No competing interests reported.

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The Role of PPP2R2B in Pancreatic Cancer Progression: A Novel Pro-Cancer Factor

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Abstract

Figures

Highlights

Introduction

Materials and methods

Data and resources

Functional enrichment analysis

Patients and samples

Cell lines and cell culture

Quantitative real-time PCR (qRT-PCR)

Western blotting (WB)

Immunohistochemistry (IHC) staining

Cell counting Kit‑8 (CCK-8) assay

5-Ethynyl-2’-deoxyuridine (EdU) assay

Wound healing assay

Migration and invasion assay

Animal experiment

Statistical analysis

Results

PPP2R2B's increased expression is observed in human PC cell lines and tissues

Correlation of PPP2R2B expression with clinical and pathological characteristics

The inhibition of PPP2R2B inhibit the proliferation, migration, and invasion of PC cells

PPP2R2B knockdown inhibited the MAPK/EMT signaling pathway activity in PC

PPP2R2B stimulated PC tumor growth in vivo

Discussion

Conclusion

Declarations

Funding

Author Contribution

Acknowledgements:

Data availability

References

Additional Declarations

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