[Construction and verification of pancreatic fistula risk prediction model after pancreaticoduodenectomy based on ensemble machine learning].

Objective: To construct an ensemble machine learning model for predicting the occurrence of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy and evaluate its application value. Methods: This is a research on predictive model. Clinical data of 421 patients undergoing pancreaticoduodenectomy in the Department of Pancreatic Surgery,Union Hospital Affiliated to Tongji Medical College,Huazhong University of Science and Technology from June 2020 to May 2023 were retrospectively collected. There were 241 males (57.2%) and 180 females (42.8%) with an age of (59.7±11.0)years (range: 12 to 85 years).The research objects were divided into training set(315 cases) and test set(106 cases) by stratified random sampling in the ratio of 3∶1. Recursive feature elimination is used to screen features,nine machine learning algorithms are used to model,three groups of models with better fitting ability are selected,and the ensemble model was constructed by Stacking algorithm for model fusion. The model performance was evaluated by various indexes,and the interpretability of the optimal model was analyzed by Shapley Additive Explanations(SHAP) method. The patients in the test set were divided into different risk groups according to the prediction probability (P) of the alternative pancreatic fistula risk score system (a-FRS). The a-FRS score was validated and the predictive efficacy of the model was compared. Results: Among 421 patients,CR-POPF occurred in 84 cases (20.0%). In the test set,the Stacking ensemble model performs best,with the area under the curve (AUC) of the subject's work characteristic curve being 0.823,the accuracy being 0.83,the F1 score being 0.63,and the Brier score being 0.097. SHAP summary map showed that the top 9 factors affecting CR-POPF after pancreaticoduodenectomy were pancreatic duct diameter,CT value ratio,postoperative serum amylase,IL-6,body mass index,operative time,albumin difference before and after surgery,procalcitonin and IL-10. The effects of each feature on the occurrence of CR-POPF after pancreaticoduodenectomy showed a complex nonlinear relationship. The risk of CR-POPF increased when pancreatic duct diameter<3.5 mm,CT value ratio<0.95,postoperative serum amylase concentration>150 U/L,IL-6 level>280 ng/L,operative time>350 minutes,and albumin decreased by more than 10 g/L. The AUC of a-FRS in the test set was 0.668,and the prediction performance of a-FRS was lower than that of the Stacking ensemble machine learning model. Conclusion: The ensemble machine learning model constructed in this study can predict the occurrence of CR-POPF after pancreaticoduodenectomy,and has the potential to be a tool for personalized diagnosis and treatment after pancreaticoduodenectomy.

Folate and vitamin B-6 status are not associated with homocysteine, oxidative stress and antioxidant capacities in patients with hepatocellular carcinoma.

The purpose of this study was to study the effects of serum folate and plasma pyridoxal 5'-phosphate (PLP) on plasma homocysteine, oxidative stress and antioxidant capacities in 44 hepatocellular carcinoma (HCC) patients and 56 healthy controls. The responses of folate, vitamin B-6, homocysteine, oxidative stress and antioxidant enzyme activities in HCC patients before and after tumor resection were also determined. Patients with HCC before tumor resection had significantly lower folate, PLP, homocysteine, glutathione peroxidase and superoxide dismutase levels, but higher malondialdehyde, total antioxidant capacity and glutathione S-transferase activity when compared with healthy controls. Oxidative stress was significantly decreased to a level similar to that of healthy controls after tumor resection in the HCC group. There were no associations of folate and PLP with plasma homocysteine, indicators of oxidative stress and antioxidant capacities. Serum folate and plasma PLP were not significant factors affecting plasma homocysteine, oxidative stress and antioxidant capacities in patients with HCC.

The G-protein coupled estrogen receptor, GPER: The inside and inside-out story.

GPER possesses structural and functional characteristics shared by members of the G-protein-coupled receptor (GPCR) superfamily, the largest class of plasma membrane receptors. This newly appreciated estrogen receptor is localized predominately within intracellular membranes in most, but not all, cell types and its surface expression is modulated by steroid hormones and during tissue injury. An intracellular staining pattern is not unique among GPCRs, which employ a diverse array of molecular mechanisms that restrict cell surface expression and effectively regulating receptor binding and activation. The finding that GPER displays an intracellular predisposition has created some confusion as the estrogen-inducible transcription factors, ERα and ERß, also reside intracellularly, and has led to complex suggestions of receptor interaction. GPER undergoes constitutive retrograde trafficking from the plasma membrane to the endoplasmic reticulum and recent studies indicate its interaction with PDZ binding proteins that sort transmembrane receptors to synaptosomes and endosomes. Genetic targeting and selective ligand approaches as well as cell models that express GPER in the absence of ERs clearly supports GPER as a bonafide "stand alone" receptor. Here, the molecular details that regulate GPER action, its cell biological activities and its implicated roles in physiological and pathological processes are reviewed.

Second and third hepatectomies for recurrent hepatocellular carcinoma are justified.

BACKGROUND: Liver resection is the main curative treatment for hepatocellular carcinoma (HCC), but recurrence rates are high. The remnant liver is the most common site of recurrence, but the role of repeat hepatectomy in the treatment of recurrent HCC is controversial. METHODS: Patients who underwent curative hepatectomy for HCC and subsequent repeat hepatectomy for recurrent HCC between 1990 and 2007 were reviewed retrospectively. Clinicopathological characteristics, and early- and long-term outcomes of patients who had a first, second, third and fourth hepatectomy were compared. RESULTS: Some 1177 patients underwent a first hepatectomy for HCC, and 149, 35 and eight patients respectively had a second, third and fourth hepatectomies for recurrence. There were no significant differences in early postoperative outcomes after first and repeat hepatectomies. Five-year disease-free and overall survival rates after first, second and third hepatectomies were 43.6, 31.8 and 33.8 per cent (P = 0.772), and 52.4, 56.4 and 59.4 per cent (P = 0.879), respectively. Patients undergoing second and third hepatectomies for recurrence had better survival rates than those who did not have a repeat hepatectomy, but not those after fourth hepatectomy. CONCLUSION: Second and third hepatectomies seem justified for hepatic recurrence of HCC. The role of fourth hepatectomy needs further investigation.

Liver resection for hepatocellular carcinoma in patients with cirrhosis.

BACKGROUND: Although liver resection is now a safe procedure, its role for hepatocellular carcinoma (HCC) in patients with cirrhosis remains controversial. METHODS: This study compared the results of liver resection for HCC in patients with cirrhosis over two time intervals. One hundred and sixty-one patients had resection during period 1 (1991-1996) and 265 in period 2 (1997-2002). Early and long-term results after liver resection in the two periods were compared, and clinicopathological characteristics that influenced survival were identified. RESULTS: Tumour size was smaller, indocyanine green retention rate was higher, patients were older and a greater proportion of patients were asymptomatic in period 2 than period 1. Operative blood loss, need for blood transfusion, operative mortality rate, postoperative hospital stay and total hospital costs were significantly reduced in period 2. The 5-year disease-free survival rates were 28.2 and 33.9 per cent in periods 1 and 2 respectively (P = 0.042), and 5-year overall survival rates were 45.9 and 61.2 per cent (P < 0.001). Multivariate analysis identified serum alpha-fetoprotein level, need for blood transfusion and Union Internacional Contra la Cancrum tumour node metastasis stage as independent determinants of disease-free and overall survival. CONCLUSION: The results of liver resection for HCC in patients with cirrhosis improved over time. Liver resection remains a good treatment option in selected patients with HCC arising from a cirrhotic liver.

Liver resection for hepatocellular carcinoma in patients with end-stage renal failure.

BACKGROUND AND OBJECTIVES: Surgical resection remains the main option for curing hepatocellular carcinoma (HCC). However, liver resection in patients with end-stage renal disease (ESRD) is risky. The aim of this study is to clarify the role of liver resection for treating HCC in patients with ESRD. METHODS: A retrospective review was carried out on 468 patients who underwent liver resection for HCC between 1989 and 1999. The clinicopathological characteristics and operative results of 12 patients who had ESRD (ESRD group) were compared with those of the other 456 patients who did not have ESRD (non-ESRD group). In the ESRD group, heparin-free hemodialysis using the periodic saline-rinse method was performed during the perioperative period. RESULTS: The ESRD group had lower hemoglobin and a higher serum creatinine levels. Other patient background and tumor pathological characteristics were comparable between the two groups as well. The operative morbidity and mortality between the two groups were also similar. The 5-year disease-free survival rates for ESRD and non-ESRD groups were 35.0 and 34.2% (P = 0.31), respectively, while the 5-year actuarial survival rates were 67.8 and 53.3% (P = 0.54), respectively. CONCLUSION: With improving techniques and knowledge of dialysis, liver resection for HCC is justified in selected patients with ESRD.

The effect of arsenic trioxide on the expression of Hsc and HNF4 in nuclear matrix proteins in HepG2 cells.

Anticancer agents interfere with the proliferation and survival of tumor cells by a variety of mechanisms. An important factor in the development of a cytotoxic effect by certain anticancer agents is the localization of drug-induced lesions within the cell nucleus. Drug-target interactions at the level of nuclear matrix (NM) may be critical events in the induction of cell death by some of these agents. Arsenic trioxide (As2O3) was identified as a very potent anti-leukemic agent by inducing apoptosis. The present study shows that As2O3 significantly inhibits the growth of hepatoblastoma cell line, HepG2, changes the composition of nuclear matrix proteins and reduces the expression of Hsc 70 and HNF4 in HepG2, which in turn initiate a cascade of events that compromise multiple nuclear functions and, ultimately, cell survival.

Expression of laminin in metastatic melanoma cell lines with different metastatic potential.

Cancer metastasis is a complex multi-step process in which tumor cells leave the primary site and develop a secondary tumor in distant organs. Laminin plays an important role in this process. The expression of laminin in four melanoma cell lines with different metastatic potentials was investigated by immunohistochemistry, immunogold electron microscopy and Western blotting. Our results showed that the expression of endogenous laminin and the percentage of the positive cells are higher with increased metastatic potentials. It is, thus, suggested that endogenous laminin may contribute to the different metastatic properties in the melanoma cell line.

Alteration of nuclear matrix protein composition of neuroblastoma cells after arsenic trioxide treatment.

The aims of the present study were to assess the effects of arsenic trioxide on the nuclear matrix protein profiles of mouse neuroblastoma cells. Arsenic trioxide induces apoptosis of acute promyelocytic leukemia cells. Our results demonstrated that 2 microM As2O3 could significantly inhibit the growth of Neuro-2a cells. As early as 24 hours after As2O3 treatment, we began to observe the alteration of nuclear matrix proteins and apoptosis in tumor cells by TUNEL assay but not by DNA ladder. An increase expression of Hsc in nuclear matrix proteins of 2 microM As2O3 treated cells was also noted. Our results also showed that before a mass range of apoptosis occurred, the composition of nuclear matrix proteins had altered. Hence the alteration of nuclear matrix proteins, such as increased expression of Hsc, may be a sensitive indicator for the detection of early apoptosis.

Human papillomavirus 16 E6 is associated with the nuclear matrix of esophageal carcinoma cells.

AIM: To explore the etiologic role of HPV infection in esophageal carcinoma, and the association of HPV-16 E6 with the nuclear matrix of carcinoma cells. METHODS: Two esophageal carcinoma cell lines,EC/CUHK1 and EC/CUHK2, were tested for HPV-16 E6 subgenetic fragment by polymerase chain reaction amplification of virus DNA associated nuclear matrix. RT-PCR and immunocytochemistry were also used to visualize the expression of E6 subgene in the cells. RESULTS: The HPV-16 E6 subgenetic fragment was found to be present in nuclear matrix-associated DNA, E6 oncoprotein localized in the nucleus where it is tightly associated with nuclear matrix after sequential extraction in EC/CUHK2 cells. It was not detected, however, in EC/CUHK1 cells. CONCLUSION: The interaction between HPV-16 E6 and nuclear matrix may contribute to the virus induced carcinogenesis in esophageal carcinoma.

The measurement of AgNORs in human glioma cells.

Sixty gliomas obtained by neurosurgical resections were examined. Paraffin blocks were retrieved from pathological files of the Second Affiliated Hospital in Guangzhou Medical College. The methods of argyrophilic technique for AgNORs staining, and Image Analysis System for measurement of AgNORs were used. Six parameters, which included hcount, count, narea, agnrea, agpern and agperc were used to correlated well with histopathological grades (compared grade 2 & 3, grade 3 & 4, and grade 2 & 4, respectively). We concluded that AgNORs is useful in evaluating proliferative activity and assessing the malignancy of human gliomas. It may also be used as a target for anti-neoplastic drugs in the treatment of gliomas.

Effects of all-trans-retinoic acid on human esophageal carcinoma cells and their nuclear matrices.

Esophageal cancer is a common cancer among ethnic Chinese. The reported incidence of esophageal cancer has increased many fold in the past decades and is apparently still rising. Nuclear matrix forms the scaffold of the nucleus and participates in various nuclear functions. Cancer specific nuclear matrix proteins have been identified in several tumor systems. 2-D gel analysis shows the presence of novel nuclear matrix proteins in ATRA treated tumor cells and these proteins are cell line specific. Our preliminary study also shows ATRA altered the nuclear matrix density of tumor cells. The significance of these nuclear matrix proteins is discussed.

Expression of bcl-2 and Bax in EGFR-antisense transfected and untransfected glioblastoma cells.

Glioblastomas are the most frequent and most malignant astrocytic gliomas. The epidermal growth factor receptor (EGFR) gene is the most frequently amplified and overexpressed in glioblastomas. The expression of bcl-2 and Bax in EGFR-antisense transfected and un-transfected glioblastoma cell line, U87E and U87V was studied by immunohistochemistry and western blotting. Our results show that the expression of Bax was stronger and bcl-2 was weaker in EGFR-antisense transfected cell line than the untransfected control. Bcl-2 and Bax genes are probably involved in the reduction of malignancy of glioblastoma cell caused by the introduction of EGFR-antisense into these tumor cells.

Bcl-2 and Bax proteins are nuclear matrix associated proteins.

Bcl-2 and Bax proteins are implicated in the regulation of apoptosis. Nuclear matrix has been demonstrated to be associated with a vast array of functional and regulatory properties of cells. NuMA is one member of a class of nuclear matrix proteins that resides in both the nucleus and mitotic apparatus. The nuclear lamins appear to form a thin fibrous structure immediately underlying the inner nuclear membrane of eukaryotic cell nuclei. The association of bcl-2 and Bax protein with nuclear matrix in glioblastoma cell line U343 was studied by confocal microscopy and Western blotting. Confocal microscopic images display that bcl-2 was localized at the peripheral of the nuclear matrix and Bax protein was located in the nuclear matrix. Western blotting detected a 26 kDa bcl-2 band and a specific band of Bax at around 66 kDa in nuclear matrix proteins. Our results suggest that bcl-2 and Bax proteins are nuclear matrix associated proteins.

A study on the relationship between antisense EGFR cDNA fragments and nuclear matrix proteins in glioblastoma cells.

The association of antisense epidermal growth factor receptor (EGFR) cDNA fragments with nuclear matrix from EGFR-antisense transfected glioblastoma cell lines U343 and U87 was investigated. A 1015 bp DNA fragment (primer I-II) was amplified in both genomic DNA and nuclear matrix-associated DNA (NM DNA) from EGFR-antisense transfected glioblastoma cell lines U343E and U87E. Two different DNA fragments (940 bp and 110 bp) were amplified by primer I-III in both genomic DNA and NM DNA of U343E, while one 110 bp PCR product was shown with the same primer in both genomic DNA and NM DNA of U87E only. After EGFR-antisense transfection, the binding property of the 110 bp DNA fragment (primer IV-V) to nuclear matrix was not affected. Southwestern blotting demonstrated the presence of antisense EGFR cDNA binding nuclear matrix proteins. Our findings demonstrate that not only EGFR DNA is associated with nuclear matrix, but the transfected antisense EGFR cDNA also binds to nuclear matrix proteins. The nuclear matrix is most likely involved in the replication and transcription of antisense EGFR cDNA or hybridisation with sense mRNA in vitro.

Treatment of hemoglobin Bart's hydrops with bone marrow transplantation.

A 21-month-old girl with hemoglobin Bart's hydrops received bone marrow transplantation (BMT) from a matched sibling. No major BMT-related complications developed. Hemoglobin levels remained greater than 10 gm/dl for 20 months without blood transfusion support despite the presence of residual host hemopoietic cells from 2 months after BMT. We suggest consideration of this therapeutic option for surviving patients.

Association of EGFR gene fragments with nuclear matrices in glioblastoma cell lines.

The association of epidermal growth factor receptor DNA fragments with nuclear matrix in glioblastoma cell lines was investigated. Two different DNA fragments (primer I-III, 940 bp and primer IV-V, 110 bp) were amplified in both genomic DNA and nuclear matrix-associated DNA. It was found that the 110 bp DNA fragment (primer IV-V) from a non-encoding region was more closely associated with the nuclear matrices of cell line U343, U373, A172, and T98 than with U87. The other DNA fragment (primer I-III) was found in both the genomic DNA and NM DNA from cell line of U343 and U87. Another long DNA fragment (primer I-II, 1015 bp) was not detected in the DNA of all cell lines. Our findings suggest that the attachment of the 110 bp DNA fragments to nuclear matrix may contribute to the growth and malignancy of glioblastoma.

Electrophoretic analysis of nuclear matrix proteins in human hepatocellular carcinoma.

The nuclear matrix is the non-chromatin skeleton of the nucleus. This structure contributes to the shape of the nucleus and regulates various nuclear functions. In this study, nuclear matrix proteins of human normal liver, a liver cancer cell line, HepG2, and hepatocellular carcinomas (HCC) were investigated. Using high resolution two-dimensional polyacrylamide gel electrophoresis, the nuclear matrix proteins of 3 normal liver and 14 HCC were compared and contrasted. A high degree of similarity between normal liver, HepG2, and HCC nuclear matrix protein patterns was found. Two HCC specific nuclear matrix proteins were identified. Among these, one protein (HCC-1, Mr 62 kd, pI 5.3) appeared in all tumor samples and HCC-2 (Mr 33.25, pI 5.3-5.5) was present in 9/11 tumors, but absent in normal liver and HepG2. Our results indicate the presence of HCC specific nuclear matrix proteins. These matrix proteins may be used as markers for HCC.

Expression of nm23-H1 in human meningioma cells.

The expression of nm23-H1 has been demonstrated to be highly correlated with the metastatic potential of various tumors. In the present investigation, meningiomas of different pathological grades were used to study on their nm23-H1 expression. Immunohistochemistry showed that nm23-H1 was expressed mainly in the cytoplasm especially in the perinuclear region in explants under short-term culture. Western-blotting demonstrated the specific expression of nm23 protein in all tumor samples. The expression was also found to be sex-dependent on tumor progression in female, but not in male patients. RT-PCR results confirmed nm23-H1 expression was higher in benign tumors than in their normal counterpart. Our observations thus suggest that nm23-H1 may play an important role in the progression of meningiomas in female patients.

Fine structural observation of a nucleolar-nuclear matrix-lamina-intermediate filament system in transformed cells.

The nuclear matrix is a nonchromatin structure of the nucleus normally concealed by a much larger mass of chromatin. Several methods have been developed to remove chromatin from nucleus while preserving the underlying matrix architecture to some degree. The present study showed that after extraction of PtK2 cells and cervical carcinoma cells (CC3) with Triton X-100, ammonium sulfate and DNase, the nucleolar-nuclear matrix-intermediate filament (Nu-Nm-L-IF) network remained. The nucleolus was oval in shape and appeared as a fibrillar mass with an accentric dense fibrillar centre. This nucleolar skeleton was in direct connection with the nuclear matrix which in turn is connected with cytoplasmic intermediate filaments by lamins. It is concluded from these observations that the Nu-NM-L-IF system forms a continuous system which plays an important role in the maintenance of the nucleolar, nuclear and cytoplasmic integrity and cellular function.