[Antitumor effects of redox-responsive nanoparticles containing platinum（Ⅳ）in ovarian cancer]

Objectives: To explore the antitumor effects of redox-responsive nanoparticles containing platinum(Ⅳ)-NP@Pt(Ⅳ) in ovarian cancer. Methods: Redox-responsive polymer carriers were synthesized. Polymer carriers and platinum(Ⅳ)-Pt(Ⅳ) can self-assemble into NP@Pt(Ⅳ). Inductively coupled plasma mass spectrometry was performed to detect the platinum release from NP@Pt(Ⅳ) in reducing environment and the platinum content in ovarian cancer cells ES2 treated with cisplatin, Pt(Ⅳ) and NP@Pt(Ⅳ). The proliferation ability of the ovarian cancer cells were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was assessed by flow cytometry. Collection of primary ovarian cancer tissues from patients with primary high-grade serous ovarian cancer who were surgically treated at the Cancer Hospital of the Chinese Academy of Medical Sciences from October to December 2022. The high-grade serous ovarian cancer patient-derived xenograft (PDX) mice were intravenously injected with Cy7.5 labeled NP@Pt(Ⅳ) followed by in vivo imaging system. Mice were treated with PBS, cisplatin and NP@Pt(Ⅳ). Tumor volume and weight were measured in each group. Necrosis, apoptosis and cell proliferation of tumor tissues were detected by hematoxylin-eosin (HE) staining, TUNEL fluorescence staining and Ki-67 immunohistochemistry staining. Body weight and HE staining of heart, liver, spleen, lung and kidney of mice in each group were measured. Results: The platinum release of NP@Pt(Ⅳ) after 48 hours in reducing environment was 76.29%, which was significantly higher than that of 26.82% in non-reducing environment (P<0.001). The platinum content in ES2 cells after 4 hours and 7 hours of treatment with NP@Pt(Ⅳ) (308.59, 553.15 ng/million cells) were significantly higher than those of Pt(Ⅳ) (100.21, 180.31 ng/million cells) and cisplatin (43.36, 50.36 ng/million cells, P＜0.05). The half inhibitory concentrations of NP@Pt(Ⅳ) in ovarian cancer cells ES2, A2780, A2780DDP were 1.39, 1.42 and 4.62 μmol/L, respectively, which were lower than those of Pt(IV) (2.89, 7.27, and 16.74 μmol/L) and cisplatin (5.21, 11.85, and 71.98 μmol/L). The apoptosis rate of ES2 cells treated with NP@Pt(Ⅳ) was (33.91±3.80)%, which was significantly higher than that of Pt(Ⅳ) [(16.28±2.41)%] and cisplatin [(15.01±1.17)%, P＜0.05]. In high-grade serous ovarian cancer PDX model, targeted accumulation of Cy7.5 labeled NP@Pt(Ⅳ) at tumor tissue could be observed. After the treatment, the tumor volume of mice in NP@Pt(IV) group was (130±98) mm3, which was significantly lower than those in control group [(1 349±161) mm3, P<0.001] and cisplatin group [(715±293) mm3, P=0.026]. The tumor weight of mice in NP@Pt(IV) group was (0.17±0.09)g, which was significantly lower than those in control group [(1.55±0.11)g, P<0.001] and cisplatin group [(0.82±0.38)g, P=0.029]. The areas of tumor necrosis and apoptosis in mice treated with NP@Pt(Ⅳ) were higher than those in mice treated with cisplatin. Immunohistochemical staining revealed that there were low expressions of Ki-67 at tumor tissues of mice treated with NP@Pt(Ⅳ) compared with cisplatin. The change in body weight of mice in NP@Pt(Ⅳ) group was not significantly different from that of the control group [(18.56±2.04)g vs.(20.87±0.79)g, P=0.063]. Moreover, the major organs of the heart, liver, spleen, lung, and kidney were also normal by HE staining. Conclusion: Redox-responsive NP@Pt(Ⅳ), produced in this study can enhance the accumulation of cisplatin in ovarian cancer cells and improve the efficacy of ovarian cancer chemotherapy.

[Performance of vaginal self-sampling high-risk HPV genotyping as primary and combining cytology or viral load as secondary in cervical cancer screening]

Objective: To evaluate the efficacy of high-risk HPV (HR-HPV) genotyping with vaginal self-sampling in primary screening and combining cytology or viral load for HR-HPV positive as secondary screening strategies. Methods: The data referring to HR-HPV genotyping of self-collected sample with mass array matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS), HR-HPV viral load of physician-collected sample with hybrid capture Ⅱ (HC-Ⅱ), liquid-based cytology and histology of 8 556 women were from Shenzhen cervical cancer screening trial Ⅱ (SHENCCAST-Ⅱ) conducted between April 2009 and April 2010. The data were reanalyzed to determine the sensitivity and specificity to cervical intraepithelial neoplasia (CIN) of grade 2 or worse (CIN Ⅱ⁺), CIN of grade 3 or worse (CIN Ⅲ⁺) when HR-HPV genotyping combining with colposcopy as primary screening strategy based on varied HR-HPV subtype (strategy 1, including 5 sub-strategies: 1a: HPV 16/18 positive; 1b: HPV 16/18/58 positive; 1c: HPV 16/18/58/31/33 positive; 1d: HPV 16/18/58/31/33/52 positive; 1e: any HR-HPV positive). The data were also compared to determine the efficacy of cytology (strategy 2, including 5 sub-strategies: 2a, 2b, 2c, 2d, 2e) or HR-HPV viral load (strategy 3, including 4 sub-strategies: 3a, 3b, 3c, 3d) of physician-collected sample as a triage with HR-HPV genotyping for self-sampling HR-HPV positives. Results: (1) The HR-HPV positive rate was 13.77% (1 178/8 556) in the self-collected samples of 8 556 pregnant women. Of them,the prevalences of HPV 16/18, HPV 16/18/58, HPV 16/18/58/31/33 and HPV 16/18/58/31/33/52 were 3.16% (270/8 556), 5.14% (440/8 556), 6.66% (570/8 556) and 9.81% (839/8 556), respectively. The HR-HPV viral load ≥10 relative light units/control (RLU/CO) was 8.87%(759/ 8 556), while cytological results ≥atypical squamous cell of undetermined signification (ASCUS) were 12.05% (1 031/8 556). (2) The strategy 1e had the highest sensitivities for CIN Ⅱ⁺, CIN Ⅲ⁺ which were 92.70% and 94.33%,respectively,among 14 sub-strategies,while the lowest specificity and positive predictive value (PPV). Meanwhile,the required colposcopy referral rates were much higher than other 13 sub-strategies (13.77%). The other 4 sub-strategies of strategy 1 (1a, 1b, 1c, 1d), strategy 1a had the highest specificities for CIN Ⅱ⁺ and CIN Ⅲ⁺ (97.92%, 97.69%, respectively), while 1d had the highest sensitivities for CIN Ⅱ⁺ and CIN Ⅲ⁺ (88.41%, 92.20%, respectively). (3) Both strategies of referring self-sampling HPV 16/18 positives for immediate colposcopy followed by triage physician-collected sample cytology (≥ASCUS) or viral load (≥10 RLU/CO) for non-HPV 16/18 positives had significantly higher sensitivity and specificity for CIN Ⅱ, CIN Ⅲ⁺, as well as lower referral rates (strategy 2a and 3a). Additionally, based on these two secondary screening strategies, cumulatively using the other four HR-HPV (HPV 58, 31, 33 and 52) positives as triage for immediate colposcopy showed an enhanced sensitivity. Conclusions: Primary HR-HPV cervical cancer screening strategy based on self-sampling with triage of cytology (≥ASCUS) or viral load (≥10 RUL/CO) provides a good balance among sensitivity, specificity for CIN Ⅱ⁺ and CIN Ⅲ⁺ and the number of tests required, referral rates. The efficacy of HR-HPV genotyping combining cytology or viral load secondary screening strategies will have a spiral escalation when HPV 58, 31, 33, 52 are included.

[Study on the damage of the tight junctions of nasal mucosal epithelial cells by artemisia annua pollen]

Objective: To investigate the damage and mechanism of artemisia annua pollen on tight junction of human nasal mucosa epithelial cells (HNEpC). Methods: HNEpC were cultured in vitro. Different concentrations of artemisia annua pollen (0, 20, 40, 80, 100, 160, 200 μg/ml) were used to intervene the cells for 24 h, and the cell proliferation activity was detected by the CCK-8 method. The expression and phosphorylation of p38MAPK signaling pathway were detected by Western Blot before and after the intervention of SB203580, a p38MAPK inhibitor in HNEpC. Immunofluorescence chemical staining, Western Blot and quantitative real-time PCR (qPCR) were used to observe the expression and distribution of tight junctions Occludin and Claudin-1. SPSS 21.1 software was used for statistical analysis. Results: CCK-8 results showed that, compared with the control group, the proliferation activity of HNEpC increased after 6 h intervention with different concentrations of artemisia annua pollen (all P<0.05). After 12 h of intervention, the proliferation activity of HNEpC in the 20, 40, 80, 100 and 160 μg/ml groups was not significantly changed (all P>0.05), while that in the 200 μg/ml group was decreased (P<0.05). After the intervention for 24 h, the proliferation activity of cells in the 20 and 40 μg/ml groups was not significantly changed (all P>0.05), while that in the 80, 100, 160 and 200 μg/ml groups was decreased (all P<0.05). Immunofluorescence staining showed that the Occludin and Claudin-1 proteins in the normal control group were localized on the cell membrane and expressed more and formed a ring structure around the cell membrane. However, under the intervention of high concentration artemisia annua pollen, its expression level decreased, appeared broken, fuzzy, and nonuniform distribution. Western Blot and qPCR results showed that after 24 h of intervention, the expression levels of HNEpC Claudin-1 protein and its mRNA in the pollen groups (40, 80, 100, 160, 200 μg/ml) of artemisia annua decreased compared with those of those of the control group (mRNA expression levels were 0.567±0.214, 0.443±0.109, 0.462±0.160, 0.497±0.134, 0.388±0.076 compared with 1.001±0.067, respectively, all P<0.05). However, the mRNA of Occludin protein and its mRNA only decreased in the 200 μg/ml treatment group (mRNA expression level was 0.631±0.109 compared with 1.016±0.026, P<0.05), while all the other treatment groups increased (mRNA expression levels were 1.258±0.134, 1.827±0.103, 2.429±0.077, 1.707±0.085, 1.477±0.066 compared with 1.016±0.026, respectively, all P<0.05). Western Blot showed that p-p38MAPK expression increased after intervention with 100, 160, 200 μg/ml artemisia annua pollen for 24 h. SB203580 could inhibit the decreasing expression of Occludin caused by artemisinin pollen (mRNA expression was 1.255±0.179 compared with 0.631±0.109, P<0.05), but had no effect on Claudin-1 protein expression. Conclusion: Pollen from artemisia annua may activate p38MAPK signaling pathway and destroy the close connection of HNEpC.

[Analysis on the technical characteristics and clinical efficacy of robotic-assisted intersphincteric resection for patients with low rectal cancer]

Objective: To explore the technical characteristics and short-term clinical efficacy of robotic-assisted intersphincteric resection (ISR) for patients with low rectal cancer. Methods: A retrospective cohort study was used. Inclusion criteria: (1) rigid colonoscopy showed lower margin of the tumor ≤5 cm from the anal verge; (2) preoperative rectal MRI or endorectal ultrasound revealed staging T1-2, or T3 patients receiving concurrent chemoradiotherapy; (3) patients less than 70 years old with good function of anal sphincter before surgery; (4) no synchronous multiple primary carcinoma, and no distant metastasis; (5) the method of operation was agreed by the patient. Exclusion criteria: (1) T4 stage tumors; (2) sphincter dysfunction before operation; (3) recurrent tumors; (4) lower edge of tumors beyond the dentate line; (5) death due to non-rectal cancer during follow-up and unsatisfactory follow-up data. The clinical data of 21 patients with low rectal cancer meeting inclusion criteria undergoing robotic-assisted ISR at our department from January 2015 to June 2018 were collected. Parameters during and after operation were observed. Anorectal manometry was performed at 3, 6, and 12 months after the operation, and anal function was evaluated at 3, 6, and 12 months after the closure of the stoma by Kirwan classification and Wexner fecal incontinence score. The key steps of the operation are as follows: according to the principle of total mesorectal excision, the robot continued to enter into the levator ani hiatusdistally, and dissectin the sphincter space; according to the scope of sphincter resection, ISRwas divided into partial ISR, subtotal ISR, and total ISR; subtotal and total ISR usually needed to be combined with transanal pathway. The reconstruction of digestive tract was performed by double stapler anastomosis under laparoscope orhand-sewnanastomosis under direct vision, and preventive ileostomy was completed in the right lower abdomen. Results: Of 21 patients, 13 were male and 8 were female with mean age of (57.5±16.3) years. All the patients successfully completed the operation without conversion to laparotomy. Fourteen cases (66.7%) adopted partial ISR through complete transabdominal approach, 6 cases (28.6%) adopted the subtotal ISR through combined transabdominal and transanal approachs, and 1 case (4.8%) adopted the total ISR through the combined transabdominal and transanal approachs. The total operation time was (213.1±56.3) minutes, including (27.3±5.4) minutes for mechanical arm installation and (175.7±51.6) minutes for robotic operation. The amount of intraoperative hemorrhage was (62.8±23.2) ml, and no blood transfusion was performed in any patient. All patients underwent prophylactic ileostomy, and the stoma was closed 3-6 months after the operation. Except one case of anastomotic leakage, all other stomas were closed successfully. The postoperative hospitalization time was (7.6±2.2) days, and time to fluid intake was (3.3±0.9) days. One case of anastomotic leakage, one case of anastomotic stenosis, one case of inflammatory external hemorrhoids and one case of urinary retention occurred after surgery,and all of them were cured by conservative treatment. The mean diameter of tumors was (2.9±1.2) cm, and the number of harvested lymph node was 12.8 ± 3.3. In the whole group, the circumcision margin was negative, the proximal margin was (12.2 ± 2.1) cm, the distal margin was (1.1 ± 0.4) with all negative, and the R0 resection rate was 100%. The results of anorectal manometry showed that the preoperative rest pressure, rectal maximum squeeze pressure, initial sensory volume and maximum tolerated volume were (45.19±8.46) mmHg, (128.18±18.80) mmHg, (44.33±10.11) ml and (119.00±19.28) ml, respectively;these parameters reduced significantly 3 months after operation and they were (23.44±5.54) mmHg, (93.72±12.15) mmHg, (17.72±5.32) ml and (70.44±10.9) ml, respectively. The differences were statistically significant (all P<0.001). The resting pressure and the rectal maximum squeeze pressure returned to preoperative levels 12 months after operation, which were (39.33±6.64) mmHg and (120.58±16.47) mmHg, respectively (both P>0.05), while the initial sensory volume and the maximum tolerated volume failed to reach the preoperative state, which were (30.67±7.45) ml and (92.25±10.32) ml, respectively (both P<0.05). The patients were followed up for (22.1±10.6) months without local recurrence and distant metastasis. Eighteen patients were evaluated for anal function: Kirwan classification was grade I for 6 cases, grade II for 7 cases, grade III for 4 cases, and grade IV for 1 case; Wexner incontinence score was 8.6±0.8; 14 cases had good defecation control. Conclusion: The clinical efficacy of ISR with Da Vinci robot in the treatment of low rectal cancer is satisfactory.

Effect of matrine on reducing damage to bovine mammary epithelial cells induced by Staphylococcus aureus alpha-hemolysin

Taking bacterial virulence factors as targets is a new therapy for treating host bacterial infection. The aim of this study was to investigate the effect of matrine on α-hemolysin production of Staphylococcus aureus (S. aureus) and reducing the damage to bovine mammary epithelial cells (BMECs) induced by S. aureus α-hemolysin. Subinhibitory concentrations of matrine decreased the production of α-hemolysin in none dose-dependent manner and matrine exhibited a protective effect on S. aureus-induced BMECs injury. The results indicated that the structure of matrine may potentially be used as a basic structure for development of drugs aimed at curing and preventing dairy bovine mastitis.

Novel method for esophagojejunal anastomosis after laparoscopic total gastrectomy: Semi-end-to-end anastomosis

AIM: To test a new safe and simple technique for circular-stapled esophagojejunostomy in laparoscopic total gastrectomy (LATG).

METHODS: We selected 26 patients with gastric cancer who underwent LATG and Roux-en-Y gastrointestinal reconstruction with semi-end-to-end esophagojejunal anastomosis.

RESULTS: LATG with semi-end-to-end esophagojejunal anastomosis was successfully performed in all 26 patients. The average operation time was 257 ± 36 min, with an average anastomosis time of 51 ± 17 min and an average intraoperative blood loss of 88 ± 46 mL. The average postoperative hospital stay was 8 ± 3 d. There were no complications and no mortality in this series.

CONCLUSION: The application of semi-end-to-end esophagojejunal anastomosis after LATG is a safe and feasible procedure, which can be easily performed and has a short operation time in terms of anastomosis.

[Short-term efficacy of da Vinci robotic surgical system on rectal cancer in 101 patients]

OBJECTIVE

To investigate the feasibility and safety of da Vinci robotic surgical system in rectal cancer radical operation, and to summarize its short-term efficacy and clinical experience.

METHODS

Data of 101 cases undergoing da Vinci robotic surgical system for rectal cancer radical operation from March 2010 to September 2012 were retrospectively analyzed. Evaluation was focused on operative procedure, complication, recovery and pathology.

RESULTS

All the 101 cases underwent operation successfully and safely without conversion to open procedure. Rectal cancer radical operation with da Vinci robotic surgical system included 73 low anterior resections and 28 abdominoperineal resections. The average operative time was (210.3±47.2) min. The average blood lose was (60.5±28.7) ml without transfusion. Lymphadenectomy harvest was 17.3±5.4. Passage of first flatus was (2.7±0.7) d. Distal margin was (5.3±2.3) cm without residual cancer cells. The complication rate was 6.9%, including anastomotic leakage(n=2), perineum incision infection(n=2), pulmonary infection (n=2), urinary retention (n=1). There was no postoperative death. The mean follow-up time was(12.9±8.0) months. No local recurrence was found except 2 cases with distant metastasis.

CONCLUSION

Application of da Vinci robotic surgical system in rectal cancer radical operation is safe and patients recover quickly The short-term efficacy is satisfactory.

Autophagy protects against oxaliplatin-induced cell death via ER stress and ROS in Caco-2 cells

Oxaliplatin is included in a number of effective combination regimens used as first and subsequent lines of therapy for metastatic colorectal cancer. Accumulating evidence indicates that autophagy plays a significant role in response to cancer therapy. However, the role of autophagy in oxaliplatin-induced cell death remains to be clarified. In this study, we showed that oxaliplatin induced cell death and autophagy in Caco-2 colorectal cancer cells. The suppression of autophagy using either pharmacologic inhibitors (3-methyladenine, bafilomycin A1) or RNA interference in essential autophagy genes (ATG5 or Beclin1) enhanced the cell death and reactive oxygen species (ROS) production induced by oxaliplatin in Caco-2 cells. Blocking oxaliplatin-induced ROS production by using ROS scavengers (NAC or Tiron) decreased autophagy. Furthermore, numerous dilated endoplasmic reticula (ER) were present in oxaliplatin-treated Caco-2 cells, and blocking ER stress by RNA interference against candidate of metastasis-1 (P8) and C/EBP-homologous protein (CHOP) decreased autophagy and ROS production. Taken together, these data indicate that oxaliplatin activates autophagy as a cytoprotective response via ER stress and ROS in human colorectal cancer cells.

Laparoscopy-assisted resection for gastric stump cancer and gastric stump recurrent cancer: a report of 15 cases

OBJECTIVE

This study was designed to investigate the technical methods and clinical therapeutic effects of laparoscopy-assisted resection of gastric stump cancer (GSC).

METHODS

Laparoscopy-assisted resection was performed on 15 patients with GSC. The approach, method, difficult points, and techniques of the operation were analyzed, and its clinical therapeutic effect was evaluated.

RESULTS

With the help of laparoscopy, D2 radical resection of gastric stump was performed on 12 patients, and palliative gastric stump resection was performed on two patients. There was one case of conversion from laparoscopic surgery to open surgery. Roux-en-Y gastric bypass was performed in all cases to reconstruct the alimentary tract. The mean operative time for laparoscopy-assisted resection was 205 ± 25 min. The mean intraoperative blood loss volume was 110 ± 40 ml. The mean number of lymph nodes removed was 18 ± 5. A gastric tube was not placed in the patients after surgery. The mean time for the recovery of intestinal function was 2.5 ± 1 days, the mean duration of postoperative liquid diet was 2.5 ± 1 days, and the mean time for the recovery of ambulatory activity was 3 ± 0.5 days. There was one case of postoperative infection of the incision site. The follow-up time was 6-40 months, with 1 case of death due to liver metastasis, 1 case of death due to peritoneal metastasis, 1 case of death due to complications from lupus erythematosus, and survival for the remaining 12 cases.

CONCLUSIONS

Laparoscopy-assisted resection of GSC is technically feasible; determination of the short- and long-term efficacies will require a larger and comparative sample study.

Electrochemical study of the effect of ADP and AMP on the kinetics of glutamate dehydrogenase

A chronoamperometric method based on the 'diffusion' layer concept of the convective system was used to assay the glutamate dehydrogenase (GLDH) activity. Once the reaction was initiated by adding the enzyme GLDH into a well-stirred nicotinamide adenine dinucleotide (NADH, coenzyme) solution, the steady-state oxidation limiting current of NADH would decrease linearly in a short time. The major advantage of this method is that it directly indicates the continuous in-situ change of the coenzyme concentration, thus, the real initial reaction rate of enzyme-catalyzed reaction, V0, can be determined. Using this method, the effect of adenosine-5'-monophosphate (AMP) and adenosine-5'-diphosphate (ADP) on the GLDH activity has been monitored. The results showed that ADP and AMP could increase the activity of GLDH. This activation mechanism was proposed by the voltammetric study.