Diagnostic value of serum vascular endothelial growth factor and interleukin-17 in primary hepatocellular carcinoma

Abstract

BACKGROUND

Despite significant advancements in the medical treatment of primary hepatocellular carcinoma (PHC) in recent years, enhancing therapeutic effects and improving prognosis remain substantial challenges worldwide.

AIM

To investigate the expression levels of serum vascular endothelial growth factor (VEGF) and interleukin (IL)-17 in patients with PHC and evaluate their diagnostic value while exploring their relationship with patients’ clinical characteristics.

METHODS

The study included 50 patients with confirmed PHC who visited Wuhan Hanyang Hospital from January 2021 to January 2022, and 50 healthy individuals from the same period served as the control group. Serum VEGF and IL-17 levels in both groups were measured by Enzyme-Linked Immunosorbent Assay, and their diagnostic value was assessed using receiver operating characteristic (ROC) curves. Pearson correlation analysis was performed to examine the relationship between serum VEGF and IL-17 levels. Pathological data of the PHC patients were analyzed to determine the relationship between serum VEGF and IL-17 levels and pathological characteristics.

RESULTS

Serum VEGF and IL-17 levels were significantly higher in the study group compared to the control group (P < 0.05). No significant association was observed between serum VEGF and IL-17 levels and gender, age, combined cirrhosis, tumor diameter, or degree of differentiation (P > 0.05). However, there was a significant relationship between clinical TNM stage, tumor metastasis, and serum VEGF and IL-17 levels (P < 0.05). Correlation analysis revealed a positive correlation between serum VEGF and IL-17 (P < 0.05). ROC analysis demonstrated that both serum VEGF and IL-17 had good diagnostic efficacy for PHC.

CONCLUSION

Serum VEGF and IL-17 levels were significantly higher in PHC patients compared to healthy individuals. Their levels were closely related to pathological features such as tumor metastasis and clinical TNM stage, and there was a significant positive correlation between VEGF and IL-17. These biomarkers may serve as valuable reference indicators for the early diagnosis and treatment guidance of PHC.

Key Words: Primary liver cancer; Vascular endothelial growth factor; Interleukin-17; Serum level; Diagnostic value; Correlation

Core Tip: The incidence and mortality rates of primary hepatocellular carcinoma (PHC) have been increasing. Despite significant advancements in medical care, improving treatment outcomes and prognosis for liver cancer remains a global challenge. This study measured the levels of vascular endothelial growth factor (VEGF) and interleukin (IL)-17 in the serum of PHC patients using Enzyme-Linked Immunosorbent Assay, with healthy individuals as controls. This study aimed to assess changes in serum VEGF and IL-17 levels and evaluate their diagnostic efficacy for PHC while exploring their correlations with patients’ clinicopathological characteristics. Our findings confirm that VEGF and IL-17 can serve as valuable reference indicators for the early diagnosis and treatment guidance of PHC, offering crucial insights for enhancing early management strategies.

INTRODUCTION

Primary hepatocellular carcinoma (PHC) is the fourth leading cause of cancer-related death worldwide[1], and its incidence and mortality rates have continued to rise in recent decades. Statistics indicate that one out of every two new cases or deaths from liver cancer occurs in China, with the trend increasing year by year, imposing a significant social and economic burden, particularly in China, where liver cancer is highly prevalent[2,3]. Despite considerable advancements in various aspects of medical care, improving treatment outcomes and prognosis for liver cancer remains a global challenge. Currently, a key approach to enhancing early detection, diagnosis, treatment, and overall survival rates in liver cancer patients is through the screening of high-risk populations[4-6].

Serum tumor markers are currently one of the primary modalities for diagnosing PHC, and they have gained increasing attention in clinical practice due to the convenience of obtaining samples and the rapidity of the assay[7]. Tumor infiltration and metastasis result from complex interactions between tumor cells and host cells, with cell adhesion playing a critical role; cell adhesion molecules are fundamental to this process[8]. Vascular endothelial growth factor (VEGF) is a specific vascular endothelial cell-stimulating factor that influences blood vessel formation in non-small cell lung cancer. It binds to relevant receptors to stimulate the proliferation of vascular endothelial cells and can also promote the exudation of intravascular substances, providing a matrix for tumor occurrence and development[9,10]. Interleukin (IL)-17 is a proinflammatory cytokine secreted by Th17 cells, which plays a significant role in recruiting neutrophils, promoting the release of inflammatory factors, and binding to IL-17 receptors to induce the expression of downstream cytokines. IL-17 can also participate in cellular immunity through Th17 cells and is closely associated with tumor development[11].

In this study, serum VEGF and IL-17 Levels in PHC patients were measured using Enzyme-Linked Immunosorbent Assay (ELISA), with healthy individuals serving as controls. The study aimed to investigate changes in serum VEGF and IL-17 levels, assess their diagnostic efficacy for PHC, and explore their relationship with the clinicopathological characteristics of patients. Currently, there is a relative lack of research on the expression of serum VEGF and IL-17 levels in PHC patients, as well as their diagnostic value and relationship with clinicopathological features. The analysis conducted in this study helps to fill this gap and may contribute to improving the overall survival rate and prognosis of liver cancer patients through early detection and diagnosis.

MATERIALS AND METHODS

Participants

Clinical and pathological data were collected from 50 patients with PHC who were diagnosed at Hanyang Hospital, Affiliated with Wuhan University of Science and Technology, China from January 2021 to January 2022. All participants were clearly diagnosed through histopathology and had not received anti-tumor medication before blood sample collection, including embolization, chemotherapy, radiotherapy, radiofrequency ablation, or anhydrous alcohol injection. These PHC patients comprised the study group. Additionally, 50 healthy individuals from the same period were selected as the control group. There was no statistically significant difference in baseline data between the two groups (P > 0.05; Table 1).

Table 1 Comparison of demographic characteristics between the control group and the study group.

Data		Control group (n = 50)	Study group (n = 50)	t/χ2 value	P value
Gender, n (%)	Male	32 (64.0)	35 (70.0)	0.407	0.523
	Female	18 (36.0)	15 (30.0)
Age (year)		48.22 ± 4.23	47.48 ± 3.73	0.940	0.349
Height (m)		1.68 ± 0.16	1.67 ± 0.15	0.322	0.748
Education level, n (%)	Elementary school and below	2 (4.0)	4 (8.0)	1.940	0.585
	Junior high school	11 (22.0)	10 (20.0)
	High School	20 (40.0)	24 (48.0)
	College and above	17 (34.0)	12 (24.0)
Marital status, n (%)	Unmarried	3 (6.0)	6 (12.0)	1.673	0.643
	Married	38 (76.0)	36 (72.0)
	Divorced	8 (16.0)	6 (12.0)
	Widowed	1 (2.0)	2 (4.0)
Place of residence, n (%)	City	28 (56.0)	31 (62.0)	0.372	0.542
	Village or town	22 (44.0)	19 (38.0)

Inclusion criteria

The study group met the diagnostic criteria for PHC[12], with a diagnosis confirmed by pathology, and no prior treatment before admission. Participants had to be over 18 years of age, possess complete clinical data, demonstrate good compliance, and be capable of cooperating with relevant examinations. The control group comprised healthy adults without any systemic diseases.

Exclusion criteria

Exclusion criteria included patients under 18 years of age, those with incomplete medical records, those with liver cancer secondary to or combined with other tumors, those with immune diseases such as AIDS or other conditions that could cause elevated study factors, and those with mental illness or serious physical conditions that would prevent cooperation with the test.

Methods

Basic demographic characteristics: The name, gender, age, height, contact information, education level, and marital status of participants were collected. Pathological information for the study group included histological classification, staging criteria, tumor diameter, presence of combined cirrhosis, degree of differentiation, and tumor metastasis.

Serum VEGF and IL-17 assay: All participants fasted for 8-12 hours before sample collection (healthy participants fasted randomly in the early morning). A 5 mL blood sample was drawn from the elbow vein into non-anticoagulated tubes in the early morning, and the samples were then separated by high-speed centrifugation at 4000 rpm for 5 minutes after clotting. VEGF and IL-17 levels were measured using an ELISA kit (eBiosciences) following the manufacturers’ instructions.

Observation indexes: (1) Observation and comparison of serum VEGF and IL-17 levels between the study group and the control group; (2) Observation and comparison of serum VEGF and IL-17 levels within the study group, categorized by different pathological characteristics; (3) Analysis of the correlation between serum VEGF and IL-17 levels in the study group; and (4) Analysis of the diagnostic value of serum VEGF and IL-17 levels for PHC.

Statistical analysis

SPSS 22.0 was used for data analysis. The correlation between serum VEGF and IL-17 Levels was assessed using Pearson correlation analysis, and the diagnostic value of serum VEGF and IL-17 for PHC was evaluated using receiver operating characteristic (ROC) curve analysis. A P value of less than 0.05 was considered statistically significant.

RESULTS

Comparison of general information between the control group and the study group

A comparison of general information, including gender, age, height, education level, marital status, and place of residence, between the control group and the study group showed no statistically significant differences (P > 0.05; Table 1).

Comparison of serum VEGF and IL-17 levels between the control group and the study group

When comparing serum VEGF and IL-17 levels between the control group and the study group, the results showed that both serum VEGF and IL-17 levels were significantly higher in the study group than in the control group (P < 0.05; Figure 1).

Figure 1 Comparison of serum vascular endothelial growth factor and interleukin-17 levels between the control group and the study group. A: Vascular endothelial growth factor levels in the two groups; B: Interleukin-17 levels in the two groups. ^aP < 0.05compared with the control group. VEGF: Vascular endothelial growth factor; IL: Interleukin.

Comparison of serum VEGF and IL-17 levels in relation to different pathological characteristics of the study group

The serum VEGF and IL-17 levels were compared across different pathological characteristics within the study groups. The results indicated no significant relationship between gender, age, combined cirrhosis, tumor diameter, or degree of differentiation and the expression of serum VEGF and IL-17 in PHC patients (P > 0.05). However, there was a significant relationship between clinical TNM stage and tumor metastasis with serum VEGF and IL-17 expression (P < 0.05; Table 2).

Table 2 Comparison of serum vascular endothelial growth factor and interleukin-17 levels in different pathological characteristics of the study groups.

Factor	Classification	Cases	VEGF (pg/mL)	P value	IL-17 (pg/mL)	P value
Gender	Male	35	264.90 ± 113.04	0.800	36.15 ± 13.26	0.228
	Female	15	274.17 ± 128.28		37.06 ± 12.07
Age	< 50 years old	36	275.39 ± 107.69	0.467	35.83 ± 11.95	0.606
	≥ 50 years old	14	248.37 ± 139.08		37.94 ± 15.15
Histological classification	Hepatocellular type	41	268.75 ± 109.59	0.892	37.00 ± 13.15	0.504
	Cholangiocyte type	9	262.83 ± 152.11		33.81 ± 11.35
TNM stage	Stage I + Stage II	19	217.72 ± 97.70	0.016	28.44 ± 11.25	< 0.001
	Stage III + Stage IV	31	298.30 ± 117.96		41.32 ± 11.25
Tumor diameter	> 5 cm	21	255.59 ± 112.66	0.538	38.93 ± 12.72	0.243
	≤ 5 cm	29	276.44 ± 120.51		34.61 ± 12.76
Combined cirrhosis	Yes	28	249.73 ± 114.81	0.223	34.64 ± 12.43	0.271
	No	22	290.53 ± 117.38		38.69 ± 13.18
Degree of differentiation	Highly differentiated	27	277.33 ± 111.53	0.532	37.78 ± 13.15	0.418
	Low differentiation	23	256.35 ± 123.74		34.82 ± 12.47
Tumor metastasis	Yes	24	304.50 ± 117.44	0.030	43.79 ± 10.90	< 0.001
	No	26	233.69 ± 106.95		29.91 ± 10.94

VEGF: Vascular endothelial growth factor; IL: Interleukin.

Correlation analysis of serum VEGF and IL-17

Pearson correlation analysis revealed a positive correlation between serum VEGF and IL-17 levels in PHC patients (r = 0.343, P = 0.015; Figure 2).

Figure 2 Correlation analysis of serum vascular endothelial growth factor and interleukin-17 levels. VEGF: Vascular endothelial growth factor; IL: Interleukin.

Diagnostic value of serum VEGF and IL-17 for PHC

The results of the ROC curve analysis showed that the diagnostic area under the curve for serum VEGF and IL-17 in PHC was 0.919. The sensitivity was 82.0% and 92.6%, and the specificity was 94.4% and 86.5%, respectively. Serum VEGF levels greater than 102.775 pg/mL or IL-17 levels greater than 13.289 pg/mL suggest that the patient is at risk of developing PHC (Table 3, Figure 3).

Figure 3 Receiver operating characteristic curve showing the diagnostic value of serum vascular endothelial growth factor and interleukin-17 for primary hepatocellular carcinoma. VEGF: Vascular endothelial growth factor; IL: Interleukin.

Table 3 Diagnostic value of serum vascular endothelial growth factor and interleukin-17 levels for primary hepatocellular carcinoma.

Indicator	AUC	95%CI	Optimal cut-off value	Sensitivity (%)	Specificity (%)
VEGF	0.919	0.861-0.977	102.775	82.00	94.40
IL-17	0.898	0.799-0.997	13.289	92.60	86.50

AUC: Area under the curve; VEGF: Vascular endothelial growth factor; IL: Interleukin.

DISCUSSION

In China, PHC, as one of the most common malignant tumors of the digestive system, ranks just behind gastric and esophageal cancers in incidence[13]. Currently, early surgical treatment is the preferred approach for PHC, but many patients miss the opportunity for surgical resection by the time they present with symptoms. Even when surgical resection is possible, the survival rate remains extremely low. Early screening and diagnostic tools for PHC mainly include imaging and serum tumor marker examinations. Methemoglobin, a traditional serum tumor marker for liver cancer[14,15], is subject to numerous clinical interference factors, and some studies[16] have shown that 30%-40% of liver cancer patients still have negative or normal methemoglobin levels. Therefore, the search for reliable serum tumor markers for PHC diagnosis remains a significant focus in current clinical research.

The persistent growth and metastasis of PHC tumor cells are closely associated with neovascularization, and VEGF is the most effective pro-angiogenic factor among tumor neovascularization factors. It promotes the proliferation of vascular endothelial cells, increases vascular permeability, and degrades the extravascular matrix, thus providing the foundation for vascular growth and extension[17,18]. Both tumor progression and metastasis are accompanied by abnormalities in VEGF, which is highly expressed in the serum and tissues of PHC patients[19], consistent with the findings of this study. This study further analyzed the relationship between different pathological characteristics and VEGF levels in PHC patients. The results showed no significant differences in serum VEGF levels based on gender, age, tumor diameter, or degree of differentiation. However, serum VEGF levels were significantly higher in patients with clinical TNM stage III + IV and tumor metastasis compared to those with clinical TNM stage I + II and no tumor metastasis (P < 0.05). Therefore, VEGF expression in PHC patients is related to tumor stage and metastasis.

IL-17 is a cytokine produced mainly by Th17 cells and neutrophils, and previous studies have found that IL-17 is involved in the pathophysiological processes of several diseases, including chronic inflammation, tumors, and autoimmune diseases[21,22]. It has been suggested that IL-17 may promote local tumor angiogenesis and invasive metastasis through a chemotactic response. Additionally, IL-17 may induce IL-6 to activate the Stat3 pathway, which upregulates the expression of anti-apoptotic and pro-angiogenic genes, thereby promoting tumor development[23,24]. The results of this study showed that serum IL-17 levels were significantly higher in patients with PHC compared to healthy individuals, indicating that IL-17 is involved in and plays a role in the onset and progression of PHC.

In this study, the relationship between different pathological characteristics and serum IL-17 levels in patients with PHC was analyzed. The results showed no significant difference in serum IL-17 Levels based on gender, age, tumor diameter, or degree of differentiation (P > 0.05). However, IL-17 levels were significantly higher in patients with tumor metastasis compared to those without metastasis, and serum IL-17 levels were significantly lower in patients with TNM stage I-II than in those with stage III-IV (P < 0.05). Pearson correlation analysis revealed a significant positive correlation between serum VEGF and IL-17 levels in PHC patients (r = 0.343, P = 0.015). This indicates that VEGF and IL-17 have a significant positive synergistic effect in the pathogenesis of PHC, suggesting their importance in the in-depth investigation of the pathogenesis of this cancer and the potential association network of therapeutic targets.

However, several limitations in this study require further consideration. First, the diagnostic value of VEGF and IL-17 in assessing the clinical parameters of PHC patients was not analyzed. Including this analysis would be beneficial for further exploring the potential of VEGF and IL-17 in determining the clinical parameters of PHC patients. Second, this study did not discuss the predictive implications of VEGF and IL-17 for the prognosis of PHC patients. Adding such an analysis could help to complement the predictive potential of these two indicators. Finally, the pathogenesis of VEGF and IL-17 in PHC was not explored through basic research. Therefore, conducting relevant analyses would further our understanding of the underlying mechanisms of PHC. Future research will address these aspects to further advance the clinical application of VEGF and IL-17 in PHC.

CONCLUSION

In summary, the levels of serum VEGF and IL-17 in PHC patients were significantly higher than those in the healthy population. A close relationship was observed between these markers and specific pathological characteristics, including tumor metastasis and clinical TNM stage. VEGF showed a significant positive correlation with IL-17, indicating that both can serve as reference indicators for the early diagnosis and treatment guidance of PHC.