[Construction of artificial neural network model for predicting the efficacy of first-line FOLFOX chemotherapy for metastatic colorectal cancer]

Objective: To explore and establish an artificial neural network (ANN) model for predicting the efficacy of first-line FOLFOX chemotherapy for metastatic colorectal cancer. Methods: A set of FOLFOX chemotherapy data from a group of patients with metastatic colorectal cancer (mCRC) (GSE104645) was downloaded from the GEO database as a training set. According to the FOLFOX protocol, the efficacy was divided into two groups: the chemo-sensitive group (including complete response and partial response) and the chemo-resistant group (including stable disease and progressive disease), including 31 cases in the sensitive group and 23 in the resistant group. Then, chip data (accessible number: GSE69657) from Fujian Medical University Union Hospital were chosen as a test set. A total of 30 patients were enrolled in the study, including 13 in the sensitive group and 17 in the resistant group. The batch effect correction was performed on the expression values of the two sets of matrices using the R 3.5.1 software Combat package. The gene expression difference of sensitive and resistant group in GSE104645 was analyzed by the GEO2R platform. P<0.05 and the absolute value of log(2)FC>0.33 (FC abbreviation of fold change) were used as the threshold value to screen the drug resistance and sensitive genes of the FOLFOX regimen. An ANN was constructed using the multi-layer perceptron (MLP) to perform the FOLFOX regimen on the GSE104645 dataset. The GSE69657 expression matrix and clinical efficacy parameters were then used for retrospective verification. Receiver operating characteristic(ROC) curves were used to evaluate the test results and predictive power. Results: A total of 2, 076 differentially expressed genes in GSE104645 were selected, of which 822 genes were up-regulated and 1, 254 genes were down-regulated in the chemo-resistance group. The down-regulated genes were sensitive genes. GO analysis of the biological processes in which the differentially expressed genes were involved, revealed that they were mainly involved in the regulation of substance metabolism. A total of 39 genes were included in the final model construction. This was a neural network model with two hidden layers. The accuracy of predicting training samples and test samples was 75.7% and 76.5%, respectively, and the area under the ROC curve was 0.875. The chip data set of our department (GSE69657) was set as the test set, and the area under the ROC curve was 0.778. Conclusions: In this study, an artificial neural network model is successfully constructed to predict the efficacy of first-line FOLFOX regimen for metastatic colorectal cancer based on the microarray, and an independent external verification is also conducted. The model has good stability and well prediction efficiency. Besides, the results of this study suggest that the gene functions related to oxaliplatin resistance are mainly enriched in the regulation process of substance metabolism.

[Comprehensive benefits of agroforestry snail control forests in Eryuan County, Yunnan Province]

OBJECTIVE

To investigate the efficiency of various agroforestry systems for snail control in plateau hilly schistosomiasis-endemic areas of Yunnan Province, so as to provide insights into the construction of agroforestry schistosomiasis control projects in plateau hilly regions.

METHODS

The pilot areas of snail control forests with various agroforestry systems were built in snail-breeding farmlands in Eryuan County, Yunnan Province in 2010, and the economic benefits and snail control effect were investigated in 2018. In addition, a fuzzy comprehensive evaluation model was created to screen the agroforestry system with high comprehensive benefits.

RESULTS

A total of 14 types of pilot areas of snail control forests with various agroforestry systems were built. Economic benefit analysis showed that the"walnut + garlic"pattern had the best economic benefit, with annual economic benefits of 270 000 Yuan/hm², followed by the"walnut + chili"pattern (annual economic benefits of 120 000 Yuan/hm²) and the "walnut + vegetables"pattern (annual economic benefits of 105 000 Yuan/hm²). No snails were detected in 8 types of the agroforestry systems, including the"walnut + chili"pattern, the"walnut + tobacco"pattern and the"walnut + garlic"pattern; however, there were snail found with various densities in other types of systems. Fuzzy comprehensive evaluation showed that the"walnut + garlic"pattern had the best comprehensive control effect, followed by the"walnut + chili"pattern and the"walnut + tobacco" pattern, while the pure grassland pattern showed no effect on snail control.

CONCLUSIONS

The agroforestry system is a preferential approach of forestry schistosomiasis control in plateau hilly schistosomiasis-endemic areas, which not only achieves snail control effects, but also promotes economic development and ecological construction in poor hilly areas.

[Langerhans cell histiocytosis of the thyroid: a case report]

Langerhans cell histiocytosis (LCH) is a rare monoclonal disease,its clinical presentation is highly variable because it can affect multiple organs, such as lung, bone, skin, lymph nodes, hypothalamopituitary axis, and other multiple sites. LCH involving the thyroid gland is extremely rare, here we reported a rare case of LCH involving thyroid, presenting as painless thyroid goiters.

[Effects of hydrogen sulfide on the secretion of cytokines in macrophages of deep partial-thickness burn wound in rats]

OBJECTIVE

To analyze the effects of exogenous hydrogen sulfide on the secretion of growth factors basic fibroblast growth factor (bFGF) and transforming growth factor β1 (TGF-β1), as well as inflammatory mediators tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) in macrophages of deep partial-thickness burn wound in rats.

METHODS

Seventy-eight SD rats were divided into normal control group (n=6), pure burn group, sodium hydrosulfide group, propargylglycine (PPG) group, and sodium hydrosulfide+ PPG group according to the random number table, with 18 rats in each of the latter four groups. Rats in normal control group did not receive any treatment, while rats in the other four groups were inflicted with 5% total burn surface area deep partial-thickness scald (hereinafter referred to as burn) on the back. Immediately after burn, rats in pure burn group, sodium hydrosulfide group, and group PPG were intraperitoneally injected with saline 2 mL/kg, sodium hydrosulfide 56 μmol/kg, and PPG 45 mg/kg respectively, while those in sodium hydrosulfide+ PPG group were intraperitoneally injected with sodium hydrosulfide 56 μmol/kg and PPG 45 mg/kg, once a day till the day before harvesting specimen. Six rats of normal control group fed for one week, and 6 rats from each of the rest four groups on post injury day (PID) 3, 7, 14 were collected respectively. Normal skin on the back of rats in normal control group and tissue in the base of wound of rats in the other four groups were harvested to isolate macrophages, and then the content of bFGF, TGF-β1, TNF-α, and IL-1β in culture supernatant of macrophages was detected with enzyme-linked immunosorbent assay. Data were processed with one-way analysis of variance, analysis of variance of factorial design, and LSD test.

RESULTS

Compared with that of normal control group [(42.6±2.5) and (18±4) pg/mL], the content of bFGF and TGF-β1 in culture supernatant of macrophages of rats in pure burn group was obviously increased at each time point (with P values below 0.01), peaking on PID 14 at (141.6±7.7) and (580±16) pg/mL respectively. Compared with that of pure burn group, the content of bFGF and TGF-β1 in culture supernatant of macrophages of rats in sodium hydrosulfide group was obviously increased at each time point (with P values below 0.01), peaking on PID 14 at (193.7±10.9) and (793±12) pg/mL respectively, while the content of bFGF and TGF-β1 in culture supernatant of macrophages of rats in group PPG was obviously decreased at each time point (with P values below 0.01), reaching the nadir on PID 3 at (62.0±7.1) and (170±10) pg/mL respectively. The content of bFGF and TGF-β1 in culture supernatant of macrophages of rats in sodium hydrosulfide+ PPG group was obviously lower than that of sodium hydrosulfide group but obviously higher than that of group PPG at each time point (with P values below 0.01), peaking on PID 14 at (151.3±9.0) and (579±9) pg/mL respectively. Compared with that of normal control group [(97±6) and (31±6) pg/mL], the content of TNF-α and IL-1β in culture supernatant of macrophages of rats in pure burn group was obviously increased at each time point (with P values below 0.01), peaking on PID 3 at (924±8) and (290±10) pg/mL respectively. Compared with that of pure burn group, the content of TNF-α and IL-1β in culture supernatant of macrophages of rats in sodium hydrosulfide group was obviously decreased at each time point (with P values below 0.01), reaching the nadir on PID 14 at (346±10) and (120±5) pg/mL respectively, while the content of TNF-α and IL-1β in culture supernatant of macrophages of rats in group PPG was obviously increased at each time point (with P values below 0.01), peaking on PID 3 at (1 232±13) and (410±10) pg/mL respectively. The content of TNF-α and IL-1β in culture supernatant of macrophages of rats in sodium hydrosulfide+ PPG group was obviously higher than that of sodium hydrosulfide group but obviously lower than that of group PPG at each time point (with P values below 0.01), reaching the nadir on PID 14 at (488±16) and (144±6) pg/mL respectively.

CONCLUSIONS

Supplementation of exogenous hydrogen sulfide in small dosage can increase the secretion of growth factors bFGF and TGF-β1 in macrophages of wound in rats with deep partial-thickness burn in the early stage and reduce the release of inflammatory mediators TNF-α and IL-1β in the meantime, thus affecting the healing of wound.

Frequency of mutation and deletion of the tumor suppressor gene CDKN2A (MTS1/p16) in hepatocellular carcinoma from an Australian population

The tumor suppressor gene CDKN2A (MTS1/p16), located on chromosome 9p21, is inactivated in a variety of tumors including melanomas and tumors of the biliary tract, pancreas, and stomach. The aim of the present study was to determine whether this gene is inactivated in hepatocellular carcinoma (HCC). Twenty-three primary HCCs and four HCC cell lines were examined. Loss of heterozygosity (LOH) analysis was performed using eight polymorphic markers immediately surrounding CDKN2A, and showed a contiguous region of loss, with the two most commonly deleted markers being D9S1604, located between the p16 and p15 genes, at which 7 of 13 informative tumors (54%) showed loss, and D9S171, with 4 of 14 LOH (29%). Exons 1, 2, and 3 of CDKN2A were amplified by polymerase chain reaction to detect homozygous deletions, and single-strand conformation polymorphism (SSCP) analysis was performed to screen for mutations. No homozygous deletions were detected in any sample. SSCP and sequence analysis showed the same nucleotide change at codon 148 in four tumors. This has been reported elsewhere as a polymorphism. One of these four tumors also contained a mutation at codon 119, resulting in the substitution of an acidic amino acid for a basic one. It is concluded that CDKN2A is infrequently deleted or mutated in HCC. The region of allelic loss upstream from CDKN2A might result in inactivation of regulatory sequences important in the expression of this gene; alternatively, a second tumor suppressor gene may be present in the region 9p21-22, proximal to CDKN2A. These possibilities require further investigation.

Design of a selectable reporter for the detection of mutations in mammalian simple repeat sequences

To study the mutator phenotype characteristic of tumors showing widespread replication errors at simple DNA repeat sequences (RER+), we designed a selectable reporter system for the detection of such mutations in mammalian cells. A hygromycin B phosphotransferase gene was rendered out-of-frame by the insertion of a (CA)13 dinucleotide repeat tract immediately following the ATG start codon, and subcloned into a retroviral expression vector containing a G418 (neo) selectable marker. Following transduction of this construct into cultured cells, clonal neo+ cell lines were established and then tested for their ability to form colonies in hygromycin B-containing medium. Using this system, we found that the HCT116, LS174T and LS180 human colon carcinoma cell lines acquire hygromycin resistance (hygr) at a 100-fold higher frequency than the HT29, SW480, DLD-1 and HCT15 human colon carcinoma and NIH3T3 fibroblast cell lines, and at a 25-fold higher rate than the Rat 6 embyro fibroblast cell line. DNA sequence analysis indicated that frameshift mutations had occurred within the CA dinucleotide repeat tract in HCT116 cells that became hygr. Thus, the mutation rates at simple repeated sequences in mammalian cell lines can be readily determined and studied using this system.

Suppression of mitogenic activity by stable expression of the regulatory domain of PKC beta

The amino-terminal regulatory domain portion of each protein kinase C (PKC) family member (which in the case of PKC beta 1 includes the pseudosubstrate, C1, V1 and C2 domains) plays an important role in regulating the kinase activity of the carboxyl-terminal catalytic domain. To examine the possibility that this regulatory domain region (designated 'PAT') might have biological functions independent of the catalytic domain, we have developed derivatives of R6 cells which stably express a truncated PKC beta 1 cDNA that encodes the amino-terminal 317 amino acids, including the entire regulatory domain. These R6-plPAT cells express abundant amounts of a 38 kDa protein which binds a labeled phorbol ester, but lacks protein kinase activity. In contrast to the 79 kDa PKC beta 1 holoenzyme which, when overexpressed in R6 cells, is found mostly in the cytosol, the 38 kDa PAT protein is predominantly associated with the particulate subcellular fraction. Furthermore, the PAT protein fails to show down-regulation following treatment of R6-plPAT cells with 12-O-tetradecanoylphorbol-13-acetate (TPA). Evidence is also presented that TPA-stimulated growth is suppressed in R6-plPAT cells. These findings suggest that the PKC beta 1 regulatory domain could be involved in the suppression of mitogenic signaling.

The effects of bile acids on phospholipase C activity in extracts of normal human colon mucosa and primary colon tumors

Phospholipase C (PLC) activity and its response to stimulation by bile acids was assayed in cellular extracts from 16 primary human colon tumors of various Duke's stages and paired adjacent normal mucosal samples. In the absence of bile acid, there was negligible degradation of phosphatidylinositol (PI) 1-stearoyl-2-[14C]-arachiodonoyl by tumor or normal tissue, but the addition of deoxycholic acid (DCA) or taurocholic acid (TCA) resulted in concentration-dependent and time-dependent stimulation of diacylglycerol (DAG) formation at optimal concentrations of 2 mM DCA and 4 mM TCA. Triton X-100 (0.125-1.0%) inhibited rather than enhanced the PI-degrading activity of these extracts, indicating that the stimulatory effects of DCA and TCA were not simply due to a detergent effect. Under the same assay conditions there was only a small amount of labeled monoacylglycerol or free arachidonic acid produced by extracts incubated in the absence or presence of DCA or TCA. No major differences in DAG production from PI were seen between paired samples of normal colon mucosa and primary colon tumors, in assays done in the presence of 2 mM TCA. Extracts from tumors in the distal part of the colon had higher activity than those from the proximal colon. This was also true for the extent of release of free arachidonic acid from labeled PI. Under the same conditions, labeled phosphatidylcholine or phosphatidylethanolamine did not serve as substrates for the colon mucosa or tumor extracts. Nor was there significant hydrolysis of the labeled DAG (1-stearoyl-2-14C-arachidonoylglycerol) by normal colon mucosa or tumor extracts, in the absence or presence of DCA or TCA. On the other hand, a low level of DAG lipase activity was detected in the presence of Triton X-100. These findings provide the first evidence that normal human colon mucosa and primary colon tumors contain a PI-specific PLC activity that is markedly stimulated by bile acids. Our results also suggest that bile acids may enhance colon carcinogenesis by acting on this enzyme system, thereby influencing signal transduction pathways in the target cells.

Surgical treatment of recurrent hepatocellular carcinoma

During the last 16 years, radical resection was performed in 392 patients with hepatocellular carcinoma (HCC). Eight patients died within 30 days after resection. The other 384 patients were discharged from hospital and closely followed for 6 to 195 months. By December 1991, 185 patients had developed a recurrent tumor, the 1-, 3-, and 5-year recurrence rates being 15.0%, 45.4%, and 55.3%, respectively. Ninety of the 185 patients underwent reoperation, including second hepatic resection (65 cases), cryosurgery (8 cases), resection of lung metastasis (6 cases), hepatic artery ligation and infusion chemotherapy (2 cases), intratumor ethanol injection (3 cases), microwave coagulation plus intratumor ethanol injection (2 cases), and exploration (4 cases). The survival rate of these 90 patients was significantly better than that of 95 patients who were treated by other palliative methods, the 5-year survival rate being 63.4% as compared with 28.6% after the first resection (P < 0.01), and 40.8% vs. 2.2% after recurrence (P < 0.01), respectively. These results suggest that reoperation for recurrent HCC might be an important approach to prolonging survival further after hepatic resection.

Microwave surgery in the treatment of hepatocellular carcinoma

Microwave surgery was employed for the treatment of 50 patients with hepatocellular carcinoma (HCC) and liver cirrhosis, including hepatectomy in 46 patients and in situ coagulation of tumor in 4 patients. In the study, 2,450 MHz microwaves were generated and transmitted to a monopolar needle electrode. For hepatectomy, the needle electrode was inserted into the liver parenchyma to coagulate the liver tissue and this was repeated at 1 cm intervals along the line where incision is anticipated. For unresectable HCC, the needle electrode was directly inserted into HCC to coagulate the cancer in situ. The average amounts of blood loss and blood transfusion for 46 hepatectomies using microwave were 215 +/- 189 ml and 274 +/- 261 ml, respectively. Eighteen patients (39.1%) did not need blood transfusion. A significant lower volume of blood loss and blood transfusion was observed in comparison with 46 matched conventional hepatectomies, 652 +/- 1,008 ml and 841 +/- 878 ml, respectively, all being P < 0.01. There were no operative mortality and complications, such as delayed bleeding, bile leakage, and abdominal infection. These results indicate that microwave surgery can be utilized safely and effectively in the field of liver surgery.

Experience with resection of segment VIII of liver for hepatocellular carcinoma

Hepatic segment VIII is located at the dome of the right liver lobe, next to the intrahepatic inferior vena cava (IVC) and is situated between the right and the middle hepatic veins. Its close relation to the IVC inferior medially makes liver cancer resection in this particular segment extremely difficult and hazardous. A personal series of 32 cases of segment VIII resection for hepatocellular carcinoma performed during the period January 1970-May 1992 is being presented. Most resections could be performed with occlusion of the porta hepatis only but some cases required total hepatic vascular exclusion. Since segment VIII is surrounded by major vessels, the extent of resection is limited in this region. Furthermore, tumor cells are easily disseminated along the vascular route. The long-term results are far from ideal. One-, 3-, and 5-year survival rates were 93.33%, 57.14%, and 28.5%, respectively. However, eight patients in this series have survived 180, 168, 104, 78, 53, 43, 43, and 36 months, respectively, and some of them have returned to work. Therefore, despite the technical difficulties involved in segment VIII resection, it is still worthwhile adopting an aggressive operative approach to this group of patients.

Experience with liver resection after hepatic arterial chemoembolization for hepatocellular carcinoma

The use of percutaneous transcatheter hepatic arterial chemotherapy and embolization in the treatment of primary liver cancer has become increasingly popular in recent years. The authors employed this method, using a combination of cisplatin, mitomycin C, 5-fluorouracil, and ethiodized oil (Lipiodol) or absorbable gelatin sponge in 30 patients with huge liver cancers (diameter range, 5.6-12.0 cm) as a preliminary treatment before liver resection. Significant tumor regression occurred after this treatment, converting these tumors into resectable lesions that were excised successfully later. Before surgery, chemoembolization was done once every 4-6 weeks. The patients underwent 1-5 treatment sessions (mean, 2.9) and then waited 1-4 months (mean, 2.4 months) before undergoing surgery. Alpha-fetoprotein levels decreased to normal in seven patients. The tumor diameters were reduced by 31.6 +/- 15.2% (2.3 +/- 1.2 cm) and the percent tumor necrotic area ranged from 40-100%. Adhesions of the tumor to the diaphragm and thickening of the hepatoduodenal ligament and gallbladder wall were the primary operative findings, but they did not significantly complicate the surgery. There was one postoperative death from acute pulmonary embolism. The 1-year, 2-year, and 3-year survival rates were 88.89%, 77.03%, and 77.03%, respectively. Although these patients still are being followed to assess their long-term survival, this treatment appears promising for patients with advanced huge liver cancers who hitherto have been denied surgery on grounds of unresectability.

Experience with liver resection after hepatic arterial chemoembolization for hepatocellular carcinoma

The use of percutaneous transcatheter hepatic arterial chemotherapy and embolization in the treatment of primary liver cancer has become increasingly popular in recent years. The authors employed this method, using a combination of cisplatin, mitomycin C, 5-fluorouracil, and ethiodized oil (Lipiodol) or absorbable gelatin sponge in 30 patients with huge liver cancers (diameter range, 5.6-12.0 cm) as a preliminary treatment before liver resection. Significant tumor regression occurred after this treatment, converting these tumors into resectable lesions that were excised successfully later. Before surgery, chemoembolization was done once every 4-6 weeks. The patients underwent 1-5 treatment sessions (mean, 2.9) and then waited 1-4 months (mean, 2.4 months) before undergoing surgery. Alpha-fetoprotein levels decreased to normal in seven patients. The tumor diameters were reduced by 31.6 +/- 15.2% (2.3 +/- 1.2 cm) and the percent tumor necrotic area ranged from 40-100%. Adhesions of the tumor to the diaphragm and thickening of the hepatoduodenal ligament and gallbladder wall were the primary operative findings, but they did not significantly complicate the surgery. There was one postoperative death from acute pulmonary embolism. The 1-year, 2-year, and 3-year survival rates were 88.89%, 77.03%, and 77.03%, respectively. Although these patients still are being followed to assess their long-term survival, this treatment appears promising for patients with advanced huge liver cancers who hitherto have been denied surgery on grounds of unresectability.

Hepatic artery ligation and infusion chemotherapy for unresectable primary liver cancer

During the period of 1958-1989, 356 patients with pathologically proven primary liver cancer (PLC) were determined by laparotomy to be unresectable. Of the 356 patients, 51 (14.3%) were of subclinical stage, 287 (80.6%) of moderate stage and 18 (5.1%) of late stage. The association of liver cirrhosis was present in 310 patients (87.1%). Treatment modalities in 356 patients were divided into 4 groups: hepatic artery ligation (HAL) (51), hepatic artery infusion (HAI) of chemotherapeutic agents (114), HAL + HAI (117), and HAL + HAI + radiotherapy (74). The 5-year survival rate was zero in the 4 groups in the period of 1958-1977. During 1978-1989, however, the 5-year survival rate was zero in HAL, 7.9% in HAI, 24.4% in HAL + HAI (with second look resection in 10 patients), and 36.5% in HAL + HAI + radiotherapy (with second look resection in 19). The marked improvement in survival in later period was attributable to the accurate site of hepatic artery catheter, longer infusion chemotherapy, and combination treatment, particularly second look resection in some of the patients. These results indicate that HAL + HAI + combination treatment might provide a possible prolongation of survival or even resection in some patients with original unresectable PLC.