# Study on Serum miR-204 Expression Levels in Patients with Severe Pneumonia and Patients with Primary Bronchial Lung Cancer and Its Diagnostic Value

Authors: Wenhong Zheng; Wei Huang; Xuchao Yu
Journal: Evidence-Based Complementary and Alternative Medicine
 (2021)

---

## Abstract

Objective. To analyze the expression and clinical significance of miR-204 in the serum of patients with severe pneumonia (SP) and primary bronchial lung cancer (LC). Methods. 65 SP patients and 43 primary bronchial LC patients who were treated in the hospital from January 2017 to December 2018 were randomly selected as the SP group and LC group. At the same time, healthy patients from the physical examination department of the hospital were selected. 65 cases were the control group. QRT-PCR detected serum miR-204 expression and compared the differences between groups. The pathological data of patients were collected, and the relationship between serum miR-204 and the patient’s pathological data was compared; the area under the ROC curve and Kaplan–Meier curve were used to evaluate the diagnostic value of serum miR-204 for the two conditions and to explore the relationship between serum miR-204 and prognosis. Results. The serum miR-204 of the SP group was (0.43 ± 0.09), the serum miR-204 of the LC group was (0.40 ± 0.10), the serum miR-204 of the control group was (1.00 ± 0.09), and the miR-204 level of was significantly higher than that of the control group, and the difference between the groups was statistically significant (P < 0.05). There was no significant difference in serum miR-204 levels between the SP group and the LC group (P > 0.05). Serum miR-204 levels in SP patients with cumulative organs ≥3 were higher than those with cumulative organs <3, and the difference was statistically significant (P < 0.001). In the LC group, in patients with stage III to IV and low and undifferentiated patients, the level of miR-204 was higher than that of stage I∼II and high and moderately differentiated patients, and the difference was statistically significant (P < 0.001). The level of miR-204 in the two groups of patients (0.89 ± 0.10, 0.83 ± 0.13) who died of illness was significantly higher than that of the surviving patients (1.00 ± 0.11, 1.00 ± 0.10), and the difference was statistically significant (P < 0.05); the survival rate of patients with high expression of miR-204 was higher than that of patients with low expression. The AUC of serum miR-204 level to SP and LC was 0.766 and 0.818, respectively. Conclusion. The level of miR-204 in the serum of SP patients and patients with primary bronchial LC was significantly lower than that of healthy people, and patients who died were lower than those who survived; the miR-204 in serum has a good diagnostic value for SP and LC and is related to the survival and prognosis of patients.


---

## Body

## 1. Introduction

Pneumonia is a common respiratory disease. According to the place where it is acquired, it can be divided into community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP); about 50,000 people die from pneumonia every year. 20%–60% of severe pneumonia (SP) patients require hospitalization due to the severity of the disease and the underlying disease or social factors [1, 2]. 10%–22% of inpatients who reach the diagnosis of SP need to be admitted to the intensive care unit (ICU) for treatment. The morbidity and mortality of SP are high. Despite the use of antibiotics and emergency treatment measures, 44%–83% of patients still require mechanical ventilation when they are admitted to the ICU, and more than 50% of patients are complicated by septic shock, and the mortality rate is high [3]. SP is a type of pneumonia with severe disease, rapid progress, and poor prognosis. Although there are various treatment measures such as powerful anti-infective treatment and ventilator-assisted ventilation, SP has rapid changes in disease condition, complex inflammatory response, and multiple organ dysfunction syndrome (MODS), which is difficult to treat and expensive, and the prognosis is poor and the mortality rate is high [4, 5].Primary bronchial lung cancer, referred to as lung cancer (LC), is a malignant tumor that occurs in the bronchial mucosal epithelium, which can grow into the bronchial lumen and/or adjacent lung tissue and can pass through lymphatic blood or transbronchial metastasis [6]. According to pathological characteristics, non-small-cell LC can be divided into squamous cell carcinoma, adenocarcinoma, adenosquamous carcinoma, and large-cell carcinoma. Among them, lung adenocarcinoma has the highest incidence, accounting for about 50% of all LC [7–9]. Surgical treatment is the first choice for early and midterm NSCLC. However, more than 80% of clinical patients who seek medical attention after the onset of symptoms are in the advanced stage and have lost the opportunity for surgery. In addition to surgery, treatments for NSCLC include chemotherapy, radiotherapy, and traditional Chinese medicine, but the prognosis is not ideal [10].Since the biomarkers that have been used in clinical practice are not enough to provide a clear diagnosis basis for early disease, the early diagnosis and early treatment of SP and LC will be beneficial to prolong the overall survival of patients. miRNAs are RNAs with a length of 18–30 nt, which have a variety of important regulatory functions in cells. Each miRNA can have multiple target genes, and several miRNAs can also regulate the same gene. mRNA is a type of single-stranded ribonucleic acid that is transcribed from a strand of DNA as a template and carries genetic information that can guide protein synthesis [11]. In previous studies, it has been found that miR-204 can not only regulate the mRNA of target genes to play a role in diseases but also can be used as a biomarker for disease detection [12–14]. Therefore, this study aims to summarize the clinical characteristics of SP and primary bronchial LC, detect the serum miR-204 levels of both, and explore the diagnostic value of miR-204 expression levels for the disease, so as to provide a theoretical reference for the diagnosis and treatment of SP in the future.


## 2. Materials and Methods

### 2.1. General Information

65 SP patients and 43 patients with primary bronchial LC who were treated in the hospital from January 2017 to December 2018 were randomly selected as the SP group and LC group, and 65 healthy people from the physical examination department of the hospital were selected as the control group. Neither SP patients nor primary bronchial LC patients had been treated. This study was approved by the ethics committee of our hospital, and the patient or close relatives signed an informed consent form for the study protocol.


### 2.2. Inclusion Criteria and Exclusion Criteria

SP: met the diagnostic criteria revised by the American Society of Infectious Diseases/American Thoracic Society (IDsA/ATs) in 2007 [15]: (1) main criteria: invasive mechanical ventilation was required; septic shock requires vasoconstrictor treatment; (2) secondary criteria: respiratory rate ≥30 times/min; oxygenation index (Pa02/Fi02) ≤ 250; multiple-lobe infiltration; disturbance of consciousness/disorientation; azotemia (BUN≥20 mg/d1); hemocytopenia (WBC<4.0 × 109/L); thrombocytopenia (platelets<10.0 × 109/L); hypothermia (T < 36°C); low blood pressure, and strong fluid resuscitation was required. The diagnosis of severe community-acquired pneumonia that meets 1 major criterion or 3 minor criteria or more was established. The criteria for defining severe hospital-acquired pneumonia were as follows: (1) lived in the intensive care unit; (2) respiratory failure: mechanical ventilation was required or oxygen concentration of >35% was required to maintain arterial blood oxygen saturation >90%; (3) the condition progressed rapidly; X-ray showed cumulative multiple lung lobes or both lungs with infiltrating lesions and cavities; and (4) there was evidence of severe sepsis. Exclusion criteria: (1) SP patients under 18 years of age; (2) patients with severe immunosuppression (such as AIDS, blood disease, bone marrow suppression after chemotherapy, and after bone marrow transplantation); (3) those who lacked clinical data (such as medical advice and lack of examination results or inquiries); and (4) patients who were admitted to the hospital for a short period of time (within 48 h), did not cooperate with treatment, or are discharged automatically.Primary bronchial LC: (1) the patient’s personal data such as age, gender, tissue type, TNM staging, degree of tissue differentiation, and clinical pathological data were complete; (2) all postoperative pathological specimens of the patients were diagnosed as LC by pathologists; and (3) according to the WHO International Histological Classification Standards [16], the staging was carried out. Exclusion criteria: (1) patients with uncontrollable heart disease such as heart failure (congestive) and acute myocardial ischemia; (2) those who are pregnant and lactating; (3) those with uncontrollable liver and kidney function; (4) those who had received antitumor therapy (within 2 months); (5) people with mental illness; (6) people who were allergic to iodine or arsenic; (7) people with severe esophageal varices; and (8) people who did not cooperate with treatment or were discharged automatically.


### 2.3. Research Methods

#### 2.3.1. Data and Sample Collection

Clinical data related to the patient’s age, gender, and condition were collected, and the relevant data were entered. In the early morning of the next day of hospitalization, for all subjects, and the control group in the early morning of the physical examination, 3 ml of fasting blood was drawn into a centrifuge tube and centrifuged at 3000 r/min at 4°C for 15 minutes, and then, the supernatant was transferred to a new centrifuge tube for storage and reserved in a −80 refrigerator.


#### 2.3.2. qRT-PCR Detected the Level of Serum miR-204

The RNA extraction kit was used to extract serum RNA from all subjects, and the concentration of extracted RNA was determined. The RNA was reverse transcribed into cDNA using a reverse transcription kit, and then, qRT-PCR was used to detect the serum miR-204 level. The cycling conditions were 95°C 60 s; 95°C 30 s, 58°C 45 s, 72°C 30 s, and total 40 cycles, with U6 as the internal reference. The 2-∆∆Ct method [△△CT (n) = △Ct (n)−△Ct (1),△Ct (n) = Ct target gene (n)−Ct internal reference gene (n)] was used to calculate the relative expression of serum miR-204, and the experimental operation was carried out in strict accordance with the reagent instructions. miR-204 forward primer sequence: 5′-GACGCTTTCCCTTTGTCATCCT-3′, reverse primer sequence: 5′-GTGCAGGGTCCGAGGTATTC-3’. U6 forward primer sequence: 5′-ATTGGAACGATACAGAGAAGATT-3′, reverse primer sequence: 5′-GGAACGCTTCACGAATTTG-3’.


#### 2.3.3. Follow-Up Record

All patients are followed up by telephone or outpatient review, and their survival status is recorded. The deadline for follow-up is June 30, 2021. According to whether patients in all groups died during the follow-up period, patients with SP and primary bronchial LC were divided into a death group and survival group. The serum miR-204 levels of all patients were divided into a high-expression group and low-expression group according to their medians, and the relationship between serum miR-204 and the prognosis of the two conditions was explored.


### 2.4. Statistical Methods

SPSS 21.0 software was used for statistical analysis of all data. Measurement data conforming to normal distribution and uniform variance were expressed as mean ± standard deviation (x¯±s), and a t-test was used for comparison between groups; The count data were expressed in terms of the number of cases and the rate (%), and the χ2 test was used for comparison between groups; the receiver operating characteristic (ROC) curve was used to analyze the diagnostic value, and the area under the curve (AUC) was calculated; the Kaplan–Meier method was used to draw the survival curve, and the log-rank test was used for comparison between groups, and the difference was statistically significant with P < 0.05.


## 2.1. General Information

65 SP patients and 43 patients with primary bronchial LC who were treated in the hospital from January 2017 to December 2018 were randomly selected as the SP group and LC group, and 65 healthy people from the physical examination department of the hospital were selected as the control group. Neither SP patients nor primary bronchial LC patients had been treated. This study was approved by the ethics committee of our hospital, and the patient or close relatives signed an informed consent form for the study protocol.


## 2.2. Inclusion Criteria and Exclusion Criteria

SP: met the diagnostic criteria revised by the American Society of Infectious Diseases/American Thoracic Society (IDsA/ATs) in 2007 [15]: (1) main criteria: invasive mechanical ventilation was required; septic shock requires vasoconstrictor treatment; (2) secondary criteria: respiratory rate ≥30 times/min; oxygenation index (Pa02/Fi02) ≤ 250; multiple-lobe infiltration; disturbance of consciousness/disorientation; azotemia (BUN≥20 mg/d1); hemocytopenia (WBC<4.0 × 109/L); thrombocytopenia (platelets<10.0 × 109/L); hypothermia (T < 36°C); low blood pressure, and strong fluid resuscitation was required. The diagnosis of severe community-acquired pneumonia that meets 1 major criterion or 3 minor criteria or more was established. The criteria for defining severe hospital-acquired pneumonia were as follows: (1) lived in the intensive care unit; (2) respiratory failure: mechanical ventilation was required or oxygen concentration of >35% was required to maintain arterial blood oxygen saturation >90%; (3) the condition progressed rapidly; X-ray showed cumulative multiple lung lobes or both lungs with infiltrating lesions and cavities; and (4) there was evidence of severe sepsis. Exclusion criteria: (1) SP patients under 18 years of age; (2) patients with severe immunosuppression (such as AIDS, blood disease, bone marrow suppression after chemotherapy, and after bone marrow transplantation); (3) those who lacked clinical data (such as medical advice and lack of examination results or inquiries); and (4) patients who were admitted to the hospital for a short period of time (within 48 h), did not cooperate with treatment, or are discharged automatically.Primary bronchial LC: (1) the patient’s personal data such as age, gender, tissue type, TNM staging, degree of tissue differentiation, and clinical pathological data were complete; (2) all postoperative pathological specimens of the patients were diagnosed as LC by pathologists; and (3) according to the WHO International Histological Classification Standards [16], the staging was carried out. Exclusion criteria: (1) patients with uncontrollable heart disease such as heart failure (congestive) and acute myocardial ischemia; (2) those who are pregnant and lactating; (3) those with uncontrollable liver and kidney function; (4) those who had received antitumor therapy (within 2 months); (5) people with mental illness; (6) people who were allergic to iodine or arsenic; (7) people with severe esophageal varices; and (8) people who did not cooperate with treatment or were discharged automatically.


## 2.3. Research Methods

### 2.3.1. Data and Sample Collection

Clinical data related to the patient’s age, gender, and condition were collected, and the relevant data were entered. In the early morning of the next day of hospitalization, for all subjects, and the control group in the early morning of the physical examination, 3 ml of fasting blood was drawn into a centrifuge tube and centrifuged at 3000 r/min at 4°C for 15 minutes, and then, the supernatant was transferred to a new centrifuge tube for storage and reserved in a −80 refrigerator.


### 2.3.2. qRT-PCR Detected the Level of Serum miR-204

The RNA extraction kit was used to extract serum RNA from all subjects, and the concentration of extracted RNA was determined. The RNA was reverse transcribed into cDNA using a reverse transcription kit, and then, qRT-PCR was used to detect the serum miR-204 level. The cycling conditions were 95°C 60 s; 95°C 30 s, 58°C 45 s, 72°C 30 s, and total 40 cycles, with U6 as the internal reference. The 2-∆∆Ct method [△△CT (n) = △Ct (n)−△Ct (1),△Ct (n) = Ct target gene (n)−Ct internal reference gene (n)] was used to calculate the relative expression of serum miR-204, and the experimental operation was carried out in strict accordance with the reagent instructions. miR-204 forward primer sequence: 5′-GACGCTTTCCCTTTGTCATCCT-3′, reverse primer sequence: 5′-GTGCAGGGTCCGAGGTATTC-3’. U6 forward primer sequence: 5′-ATTGGAACGATACAGAGAAGATT-3′, reverse primer sequence: 5′-GGAACGCTTCACGAATTTG-3’.


### 2.3.3. Follow-Up Record

All patients are followed up by telephone or outpatient review, and their survival status is recorded. The deadline for follow-up is June 30, 2021. According to whether patients in all groups died during the follow-up period, patients with SP and primary bronchial LC were divided into a death group and survival group. The serum miR-204 levels of all patients were divided into a high-expression group and low-expression group according to their medians, and the relationship between serum miR-204 and the prognosis of the two conditions was explored.


## 2.3.1. Data and Sample Collection

Clinical data related to the patient’s age, gender, and condition were collected, and the relevant data were entered. In the early morning of the next day of hospitalization, for all subjects, and the control group in the early morning of the physical examination, 3 ml of fasting blood was drawn into a centrifuge tube and centrifuged at 3000 r/min at 4°C for 15 minutes, and then, the supernatant was transferred to a new centrifuge tube for storage and reserved in a −80 refrigerator.


## 2.3.2. qRT-PCR Detected the Level of Serum miR-204

The RNA extraction kit was used to extract serum RNA from all subjects, and the concentration of extracted RNA was determined. The RNA was reverse transcribed into cDNA using a reverse transcription kit, and then, qRT-PCR was used to detect the serum miR-204 level. The cycling conditions were 95°C 60 s; 95°C 30 s, 58°C 45 s, 72°C 30 s, and total 40 cycles, with U6 as the internal reference. The 2-∆∆Ct method [△△CT (n) = △Ct (n)−△Ct (1),△Ct (n) = Ct target gene (n)−Ct internal reference gene (n)] was used to calculate the relative expression of serum miR-204, and the experimental operation was carried out in strict accordance with the reagent instructions. miR-204 forward primer sequence: 5′-GACGCTTTCCCTTTGTCATCCT-3′, reverse primer sequence: 5′-GTGCAGGGTCCGAGGTATTC-3’. U6 forward primer sequence: 5′-ATTGGAACGATACAGAGAAGATT-3′, reverse primer sequence: 5′-GGAACGCTTCACGAATTTG-3’.


## 2.3.3. Follow-Up Record

All patients are followed up by telephone or outpatient review, and their survival status is recorded. The deadline for follow-up is June 30, 2021. According to whether patients in all groups died during the follow-up period, patients with SP and primary bronchial LC were divided into a death group and survival group. The serum miR-204 levels of all patients were divided into a high-expression group and low-expression group according to their medians, and the relationship between serum miR-204 and the prognosis of the two conditions was explored.


## 2.4. Statistical Methods

SPSS 21.0 software was used for statistical analysis of all data. Measurement data conforming to normal distribution and uniform variance were expressed as mean ± standard deviation (x¯±s), and a t-test was used for comparison between groups; The count data were expressed in terms of the number of cases and the rate (%), and the χ2 test was used for comparison between groups; the receiver operating characteristic (ROC) curve was used to analyze the diagnostic value, and the area under the curve (AUC) was calculated; the Kaplan–Meier method was used to draw the survival curve, and the log-rank test was used for comparison between groups, and the difference was statistically significant with P < 0.05.


## 3. Results

### 3.1. Basic Information of the Research Object

The clinical data of the study subjects are shown in Table1.Table 1
Clinical data of study subjects (n, x¯ ± s, %).
FactorControl group (n = 65)Severe pneumonia group (n = 43)Lung cancer group (n = 65)Age (years)43.18 ± 7.6558.14 ± 8.1865.22.14 ± 7.24Gender (male/female)35/3026/1738/27Number of days in hospital (d)—20.64 ± 10.2625.74 ± 11.64Involved organs (a)——≥3—19 (44.19%)—<3—24 (55.81%)—With chronic obstructive pulmonary disease——Yes—20 (46.51%)—No—23 (53.49%)—Mechanical ventilation——Yes—21 (48.84%)—No—22 (51.16%)—TNM staging——I∼II——50(76.92%)III∼IV——15(23.08%)Tissue differentiation——High and medium differentiation——16 (24.62%)Low and undifferentiated——49 (75.38%)Histological type——Adenocarcinoma——36 (55.38%)Squamous cell carcinoma——29 (44.62%)Case fatality rate—58.14%46.15%


### 3.2. Serum miR-204 Levels of Subjects in Each Group

The serum miR-204 of the SP group was 0.43 ± 0.09, the serum miR-204 of the LC group was 0.40 ± 0.10, the serum miR-204 of the control group was 1.00 ± 0.09, and the miR-204 of the SP group and the LC group was significantly higher than that of the control group, and the difference between the groups was statistically significant (P < 0.001). There was no significant difference in serum miR-204 levels between the SP group and the LC group (P > 0.05), as shown in Figure 1.Figure 1
Serum miR-204 levels of subjects in each group. Note: compared with the control group,∗∗P < 0.01.


### 3.3. The Relationship between Serum miR-204 Levels and the Pathological Data of the Subjects

In SP patients, the serum miR-204 level of patients with cumulative organs ≥3 was higher than that of patients with cumulative organs <3. The difference was statistically significant (P < 0.001). In the LC group, in patients with stage III to IV and low and undifferentiated patients, the level of miR-204 was higher than that of stage I∼II and high and moderately differentiated patients, and the difference was statistically significant (P < 0.001), as shown in Tables 2 and 3.Table 2
The relationship between serum miR-204 levels and pathological data of patients with severe pneumonia (n, x¯ ± s).
FactorSerum miR-204t valueP valueInvolved organs (a)≥30.38 ± 0.134.035<0.001<30.51 ± 0.08With chronic obstructive pulmonary diseaseYes0.45 ± 0.110.7210.475No0.43 ± 0.07Mechanical ventilationYes0.42 ± 0.111.9910.053No0.35 ± 0.12Table 3
The relationship between serum miR-204 levels and pathological data of lung cancer patients (n, x¯ ± s).
FactorSerum miR-204t valueP valueTNM stagingI∼II0.44 ± 0.1310.083<0.001III∼IV0.27 ± 0.05Tissue differentiationHigh and medium differentiation0.52 ± 0.078.434<0.001Low and undifferentiated0.36 ± 0.07Histological typeAdenocarcinoma0.40 ± 0.110.3940.695Squamous cell carcinoma0.39 ± 0.09


### 3.4. The Diagnostic Value of Serum miR-204 Levels for SP and LC

The AUC of serum miR-204 level to SP was 0.766, and the AUC of serum miR-204 level to LC was 0.818, and the difference was statistically significant, as shown in Table4 and Figure 2.Table 4
The diagnostic value of serum miR-204 levels in severe pneumonia and lung cancer.
DiseaseROCStd.95%CIP valueSevere pneumonia0.7660.0510.666∼0.865<0.0001Lung cancer0.8180.0370.746∼0.890<0.0001Figure 2
The diagnostic value of serum miR-204 levels in severe pneumonia and lung cancer.


### 3.5. Analysis of Serum miR-204 Levels in Patients with Death and Survival SP and LC

In SP and LC patients, the serum miR-204 level of dead patients (0.89 ± 0.10, 0.83 ± 0.13) was significantly higher than that of surviving patients (1.00 ± 0.11, 1.00 ± 0.10), and the difference was statistically significant (P < 0.05), as shown in Figure 3.Figure 3
Serum miR-204 levels in patients with severe pneumonia and lung cancer in death and survival.


### 3.6. The Relationship between Serum miR-204 Level and Patient Survival Prognosis

The median of serum miR-204 levels in SP patients was 0.45; therefore, >0.45 was high expression and ≤0.45 was low expression; the median of serum miR-204 levels in LC patients was 0.41; therefore, >0.41 was high expression and ≤0.41 was low expression; among them, the survival rate of patients with high serum miR-204 expression in SP patients was higher than that of patients with low serum miR-204 expression, and the difference was statistically significant (log-rank = 3.946,P = 0.047); patients with high serum miR-204 expression in LC patients survived. The rate is also higher than that of patients with low serum miR-204 expression, and the difference is statistically significant (log-rank = 4.197, P = 0.041), as shown in Figure 4.Figure 4
The relationship between serum miR-204 level and patient survival prognosis.


## 3.1. Basic Information of the Research Object

The clinical data of the study subjects are shown in Table1.Table 1
Clinical data of study subjects (n, x¯ ± s, %).
FactorControl group (n = 65)Severe pneumonia group (n = 43)Lung cancer group (n = 65)Age (years)43.18 ± 7.6558.14 ± 8.1865.22.14 ± 7.24Gender (male/female)35/3026/1738/27Number of days in hospital (d)—20.64 ± 10.2625.74 ± 11.64Involved organs (a)——≥3—19 (44.19%)—<3—24 (55.81%)—With chronic obstructive pulmonary disease——Yes—20 (46.51%)—No—23 (53.49%)—Mechanical ventilation——Yes—21 (48.84%)—No—22 (51.16%)—TNM staging——I∼II——50(76.92%)III∼IV——15(23.08%)Tissue differentiation——High and medium differentiation——16 (24.62%)Low and undifferentiated——49 (75.38%)Histological type——Adenocarcinoma——36 (55.38%)Squamous cell carcinoma——29 (44.62%)Case fatality rate—58.14%46.15%


## 3.2. Serum miR-204 Levels of Subjects in Each Group

The serum miR-204 of the SP group was 0.43 ± 0.09, the serum miR-204 of the LC group was 0.40 ± 0.10, the serum miR-204 of the control group was 1.00 ± 0.09, and the miR-204 of the SP group and the LC group was significantly higher than that of the control group, and the difference between the groups was statistically significant (P < 0.001). There was no significant difference in serum miR-204 levels between the SP group and the LC group (P > 0.05), as shown in Figure 1.Figure 1
Serum miR-204 levels of subjects in each group. Note: compared with the control group,∗∗P < 0.01.


## 3.3. The Relationship between Serum miR-204 Levels and the Pathological Data of the Subjects

In SP patients, the serum miR-204 level of patients with cumulative organs ≥3 was higher than that of patients with cumulative organs <3. The difference was statistically significant (P < 0.001). In the LC group, in patients with stage III to IV and low and undifferentiated patients, the level of miR-204 was higher than that of stage I∼II and high and moderately differentiated patients, and the difference was statistically significant (P < 0.001), as shown in Tables 2 and 3.Table 2
The relationship between serum miR-204 levels and pathological data of patients with severe pneumonia (n, x¯ ± s).
FactorSerum miR-204t valueP valueInvolved organs (a)≥30.38 ± 0.134.035<0.001<30.51 ± 0.08With chronic obstructive pulmonary diseaseYes0.45 ± 0.110.7210.475No0.43 ± 0.07Mechanical ventilationYes0.42 ± 0.111.9910.053No0.35 ± 0.12Table 3
The relationship between serum miR-204 levels and pathological data of lung cancer patients (n, x¯ ± s).
FactorSerum miR-204t valueP valueTNM stagingI∼II0.44 ± 0.1310.083<0.001III∼IV0.27 ± 0.05Tissue differentiationHigh and medium differentiation0.52 ± 0.078.434<0.001Low and undifferentiated0.36 ± 0.07Histological typeAdenocarcinoma0.40 ± 0.110.3940.695Squamous cell carcinoma0.39 ± 0.09


## 3.4. The Diagnostic Value of Serum miR-204 Levels for SP and LC

The AUC of serum miR-204 level to SP was 0.766, and the AUC of serum miR-204 level to LC was 0.818, and the difference was statistically significant, as shown in Table4 and Figure 2.Table 4
The diagnostic value of serum miR-204 levels in severe pneumonia and lung cancer.
DiseaseROCStd.95%CIP valueSevere pneumonia0.7660.0510.666∼0.865<0.0001Lung cancer0.8180.0370.746∼0.890<0.0001Figure 2
The diagnostic value of serum miR-204 levels in severe pneumonia and lung cancer.


## 3.5. Analysis of Serum miR-204 Levels in Patients with Death and Survival SP and LC

In SP and LC patients, the serum miR-204 level of dead patients (0.89 ± 0.10, 0.83 ± 0.13) was significantly higher than that of surviving patients (1.00 ± 0.11, 1.00 ± 0.10), and the difference was statistically significant (P < 0.05), as shown in Figure 3.Figure 3
Serum miR-204 levels in patients with severe pneumonia and lung cancer in death and survival.


## 3.6. The Relationship between Serum miR-204 Level and Patient Survival Prognosis

The median of serum miR-204 levels in SP patients was 0.45; therefore, >0.45 was high expression and ≤0.45 was low expression; the median of serum miR-204 levels in LC patients was 0.41; therefore, >0.41 was high expression and ≤0.41 was low expression; among them, the survival rate of patients with high serum miR-204 expression in SP patients was higher than that of patients with low serum miR-204 expression, and the difference was statistically significant (log-rank = 3.946,P = 0.047); patients with high serum miR-204 expression in LC patients survived. The rate is also higher than that of patients with low serum miR-204 expression, and the difference is statistically significant (log-rank = 4.197, P = 0.041), as shown in Figure 4.Figure 4
The relationship between serum miR-204 level and patient survival prognosis.


## 4. Discussion

SP is one of the critical illnesses in respiratory medicine. It is often accompanied by respiratory failure, hemodynamic disorders, rapid progress, difficult-to-control infection, poor prognosis, easy to be complicated with multiple organ dysfunction syndrome, and high mortality [17]. SP has a variety of factors that cause inflammation of the trachea and alveoli. Inflammation causes the continuous release of inflammatory mediators in the lung tissue. The inflammatory mediators can enter the blood sequentially and cause other organs in the body, leading to systemic inflammatory response syndrome. On the other hand, the weakened immune function and the excessively strong endogenous anti-inflammatory response caused by infection lead to compensatory anti-inflammatory response syndrome. When the two are out of balance and the systemic inflammatory mediators are released in a cascade, it is easy to cause severe sepsis, septic shock, respiratory failure, and other complications [18, 19].In addition to SP, the incidence of LC is also gradually increasing. LC is also one of the malignant tumors that seriously threaten human health, with a high fatality rate [20]. Studies have shown that abnormal changes in epigenetics and intracellular inheritance are the main factors that cause the production of human malignant tumor cells [21]. Epigenetic changes not only occur in the early stage of malignant tumors but also play an important role in the occurrence and development of tumors. With the development of molecular biology, the detection of biomarkers can provide an effective assessment of the prognosis of LC. The expression of miRNA is related to the growth, proliferation, migration, and other processes of tumor cells and affects the occurrence and prognosis of many diseases including tumors [22–24]. Many studies are limited to the clinical analysis of patients with SP and LC, while ignoring the importance of clinical diagnosis. Therefore, in this study, 65 patients treated with SP and 43 patients with primary bronchial LC were studied to detect the serum miR-204 level of both patients and to explore the diagnostic value of miR-204 expression level on the disease and the influence of pathological data and prognosis of patients.The results of this study showed that the levels of miR-204 in the SP group and the LC group were significantly higher than those in the control group, while the difference in serum miR-204 levels between the two disease groups was not statistically significant. It suggests that miR-204 is low in the serum of SP and LC patients and miR-204 has an inhibitory effect on inflammation. In SP patients, the degree of inflammation is high, which may be due to the low level of miR-204 [25] and miR-204 is found in liver cancer [26], thyroid cancer [27], colon cancer [28], and other diseases, and can play an antitumor effect as a tumor suppressor. Therefore, a decrease in the level of miR-204 indicates that the body is in an abnormal state, which explains why the serum miR-204 level of patients in the SP group and the LC group is low. We analyzed the relationship between the serum miR-204 level and the pathological data of the two disease groups and found that the serum miR-204 level of patients with cumulative organs ≥3 in SP patients was higher than that in patients with cumulative organs <3; in the LC group, in patients with stages III to IV and in low and undifferentiated patients, the level of miR-204 was higher than that in stage I∼II and high and moderately differentiated patients. It is suggested that the serum miR-204 level is related to the patient’s pathological data. The lower the serum miR-204 expression, the more the accumulated organs in patients with pneumonia, the higher the stage of LC patients, and the lower the degree of differentiation. Therefore, we should focus on monitoring patients with low serum miR-204 expression.Our study also compared the serum miR-204 of patients who survived and died in the two disease groups and found that the miR-204 levels of patients who died of illness in the two groups were significantly higher than those of surviving patients. We used Kaplan–Meier to draw a survival curve and found that the survival rate of patients with high miR-204 expression was higher than that of patients with low expression, and the AUC of serum miR-204 levels to SP and LC were 0.766 and 0.818, respectively. This is partly consistent with the expression in the work of Guo et al. [29].In summary, the levels of miR-204 in the serum of SP patients and patients with primary bronchial LC were significantly lower than those of healthy people, and patients who died were lower than those who survived. The miR-204 in serum has good diagnostic value for SP and LC and is related to the pathology and survival prognosis of patients.



---

*Source: 6034413-2021-10-12.xml*