Cocatalyst activity mapping for photocatalytic materials revealed by the pattern-illumination time-resolved phase microscopy.

Photocatalytic water-splitting represents a promising avenue for clean hydrogen production, necessitating an in-depth understanding of the photocatalytic reaction mechanism. The majority of the photocatalytic materials need cocatalysts to enhance the photo-oxidation or reduction reactions. However, the working mechanism, such as collecting charge carriers or reducing the reaction barrier, is not clear because they disperse inhomogeneously on a surface, and it is difficult to follow the local charge carrier behavior. This study employs the pattern-illumination time-resolved phase microscopy (PI-PM) method to unravel the spatial charge carrier behavior in photocatalytic systems, utilizing time-resolved microscopic image (refractive index change) sequences and their clustering analyses. This approach is robust for studying the change in local charge carrier behavior. We studied two major cocatalyst effects on photocatalysts: TiO2 with/without Pt and hematite with/without CoPi. The PI-PM method, supported by charge type clustering and the effects of scavengers, allowed for the analysis of local activity influenced by cocatalysts. This approach revealed that the introduction of cocatalysts alters the local distribution of charge carrier behavior and significantly impacts their decay rates. In TiO2 systems, the presence of Pt cocatalysts led to a local electron site on the micron scale, extending the lifetime to a few tens of microseconds from a few microseconds. Similarly, in hematite films with CoPi, we observed a notable accumulation of holes at cocatalyst sites, emphasizing the role of cocatalysts in enhancing photocatalytic efficiency. The study's findings highlight the complexity of charge carrier dynamics in photocatalytic processes and the significant influence of cocatalysts.

Synergy of oral recombinant methioninase (rMETase) and 5-fluorouracil on poorly differentiated gastric cancer.

Gastric cancer is highly malignant and recalcitrant to first line chemotherapies that include 5-fluorouracil (5-FU). Cancer cells are addicted to methionine for their proliferation and survival. Methionine addiction of cancer is known as the Hoffman effect. Methionine restriction with recombinant methioninase (rMETase) has been shown to selectively starve cancer cells and has shown synergy with cytotoxic chemotherapy including 5-FU. The present study aimed to investigate the efficacy of rMETase alone and the combination with 5-FU on poorly differentiated human gastric cancer cell lines (MKN45, NUGC3, and NUGC4) in vitro and vivo. rMETase suppressed the tumor growth of 3 kinds of poorly differentiated gastric cancer cells in vitro. The fluorescence ubiquitination-based cell cycle indicator (FUCCI) demonstrated cancer cells treated with rMETase were selectively trapped in the S/G2 phase of the cell cycle. In the present study, subcutaneous MKN45 gastric cancer models were randomized into four groups when the tumor volume reached 100 mm3: G1: untreated control; G2: 5-FU (i.p., 50 mg/kg, weekly, three weeks); G3: oral-rMETase (o-rMETase) (p.o., 100 units/body, daily, three weeks); G4: 5-FU with o-rMETase (5-FU; i.p., 50 mg/kg, weekly, three weeks o-rMETase; p.o., 100 units/body, daily, three weeks). All mice were sacrificed on day 22. Body weight and estimated tumor volume were measured twice a week. 5-FU and o-rMETase suppressed tumor growth as monotherapies on day 18 (p = 0.044 and p = 0.044). However, 5-FU combined with o-rMETase was significantly superior to each monotherapy (p < 0.001 and p < 0.001, respectively) and induced extensive necrosis compared to other groups. The combination of 5-FU and o-rMETase shows promise for transformative therapy for poorly differentiated gastric cancer in the clinic.

Impact of Tumor-Derived DNA Testing in Peritoneal Lavage of Pancreatic Cancer Patients with and Without Occult Intra-Abdominal Metastases.

BACKGROUND: The fractional abundance of tumor-derived DNA in body fluids depends on the metastatic sites and the degree of expansion. We aimed to assess the clinical significance of tumor-derived DNA testing in the peritoneal lavage of patients with pancreatic cancer. METHODS: The prevalence and abundance of tumor-derived DNA was assessed in 204 subjects with ascites by peritoneal lavage (AS) and the evaluable paired plasma (PL) from 149 pancreatic cancer patients undergoing abdominal exploration. Genetic profiles were evaluated by next-generation sequencing, and prognostic impact was assessed using Cox proportional hazard models. RESULTS: Of 204 subjects, AS samples from patients with peritoneal dissemination (PER+) and positive cytology (CY+) showed significantly higher prevalence and abundance of tumor-derived DNA than those with negative counterparts. Tumor-derived DNA prevalence and abundance in AS were more likely to be higher than in paired PL in a subgroup of patients with PER+ and CY+, respectively. Next-generation sequencing revealed concordant or discrepant mutational patterns between the AS and PL samples. Multivariate analysis showed that both tumor-derived DNA in AS (hazard ratio [HR] 3.940, p = 0.009) and PL (HR 2.936, p = 0.026) were independently associated with poor survival in treatment-naïve patients. In patients who underwent resection, tumor-derived DNA positivity in the AS was more predictive of early recurrence than in PL. CONCLUSIONS: Tumor-derived DNA in AS can serve as characterizing the genetic profiles of tumor cells attributable to the development of PER+ and predicting the minimal residual disease and early recurrence in patients with pancreatic cancer.

What is the impact of zinc deficiency for pancreatectomies in patients with pancreatic ductal adenocarcinoma?

BACKGROUND: and purpose: Zinc is an essential element for human health and plays an important role in metabolic, immunological and other biological processes. The present study was conducted to investigate the association between zinc deficiency (ZD) and the perioperative clinical course in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: Of 216 patients with PDAC who underwent elective pancreatectomy between 2013 and 2017 at our institution, 206 patients with sufficient clinical data were retrospectively reviewed. The perioperative variables were compared and the risk factors associated with infectious complications were identified. RESULTS: ZD was preoperatively present in 36 (17.5%) of 206 patients with PDAC. In the patients of the ZD group, a higher proportion of males, higher preoperative modified Glasgow prognostic scores, a higher neutrophil-to-lymphocyte ratio, and a higher occurrence of postoperative infectious complications after pancreatectomy were observed, compared to the non-ZD group. By a univariate analysis, three risk factors were significantly associated with infectious complications after pancreatectomy: ZD (vs non-ZD: p = 0.002), serum albumin <3.5 g/dl (vs ≥ 3.5 g/dl: p = 0.005), and the procedure of pancreaticoduodenectomy (vs others: p = 0.013). By multivariate logistic regression analysis, the occurrence of infectious complications was significantly associated with ZD (OR 3.430, 95%CI 1.570 to 7.490, p = 0.002) and the procedure of pancreaticoduodenectomy (OR 2.030, 95%CI 1.090 to 3.770, p = 0.025). CONCLUSIONS: The current study newly demonstrated that ZD could serve as a preoperative predictor of infectious complications after pancreatectomies in the patients with PDAC.

Liver resections in patients with prior bilioenteric anastomosis are predisposed to develop organ/space surgical site infections and biliary leakage: results from a propensity score matching analysis.

PURPOSE: The aims of this study were to compare the perioperative outcomes after hepatectomy with prior bilioenteric anastomosis to those without prior anastomosis, and to elucidate the mechanisms and preventative measures of its characteristic complications. METHODS: The demographic data and perioperative outcomes of 525 hepatectomies performed between January 2007 and December 2018, including 40 hepatectomies with prior bilioenteric anastomosis, were retrospectively analyzed. RESULTS: A propensity score matching analysis demonstrated that hepatectomies with prior bilioenteric anastomosis were associated with a higher frequency of major complications (p = 0.015), surgical site infection (p = 0.005), organ/space surgical site infection (p = 0.003), and bile leakage (p = 0.007) compared to those without. A multivariate analysis also elucidated that prior bilioenteric anastomosis was one of the independent risk factors of organ/space surgical site infection. In the patients with prior bilioenteric anastomosis, bile leakage was associated with organ/space surgical site infection at a significantly higher rate than those without prior bilioenteric anastomosis (p < 0.001). CONCLUSIONS: Prior bilioenteric anastomosis is a strong risk factor for organ/space surgical site infections, which might be induced by bile leakage. To prevent infectious complications after hepatectomy with prior bilioenteric anastomosis, meticulous liver transection to reduce bile leakage rate is thus considered to be mandatory.

Staging laparoscopy is mandatory for the treatment of pancreatic cancer to avoid missing radiologically negative metastases.

PURPOSE: Staging laparoscopy is considered useful for determining treatment plans for advanced pancreatic cancer. However, the indications for staging laparoscopy are not clear. This study aimed to evaluate the safety of staging laparoscopy and its usefulness for detecting distant metastases in patients with pancreatic cancer. METHODS: A total of 146 patients with pancreatic cancer who underwent staging laparoscopy between 2013 and 2019 were analyzed. Staging laparoscopy was performed in all pancreatic cancer patients in whom surgery was considered possible. RESULTS: In this cohort, 42 patients (29%) were diagnosed with malignant cells on peritoneal lavage cytology, 9 (6%) had peritoneal dissemination, and 11 (8%) had liver metastases. A total of 48 (33%) had radiologically negative metastases. On a multivariate analysis, body and tail cancer [odds ratio (OR) 5.00, 95% confidence interval (CI) 2.15-11.6, p < 0.001], high CA19-9 level [OR 4.04, 95% CI 1.74-9.38, p = 0.001], and a resectability status of unresectable (OR 2.31, 95% CI 1.03-5.20, p = 0.04) were independent risk factors for radiologically negative metastases. CONCLUSIONS: Staging laparoscopy can be safely performed and is useful for the diagnosis of radiologically negative metastases. Staging laparoscopy should be routinely performed for the accurate diagnosis of pancreatic cancer patients before pancreatectomy and/or local treatment, such as radiotherapy.

Increased neutrophil-lymphocyte ratio predicts recurrence in patients with well-differentiated pancreatic neuroendocrine neoplasm based on the 2017 World Health Organization classification.

BACKGROUND: The prognostic values of inflammation-based markers in well-differentiated pancreatic neuroendocrine neoplasms, diagnosed according to the new 2017 World Health Organization classification, have remained unclear. Therefore, we assessed the ability to predict the recurrence of such markers after curative resection in patients with these neoplasms. METHODS: Circulating/systemic neutrophil-lymphocyte, monocyte-lymphocyte, platelet-lymphocyte, and platelet-white cell ratios were evaluated in 120 patients who underwent curative resection for well-differentiated pancreatic neuroendocrine neoplasms without synchronous distant metastasis between 2001 and 2018. Recurrence-free-survival and overall survival were compared using Kaplan-Meier analysis and log-rank tests. Univariate or multivariate analyses, using a Cox proportional hazards model, were used to calculate hazard ratios with 95% confidence intervals. RESULTS: Univariate analysis demonstrated that preoperative neutrophil-lymphocyte ratio, tumor size, European Neuroendocrine Tumor Society TMN classification, 2017 World Health Organization classification, and venous invasion were associated with recurrence. The optimal preoperative neutrophil-lymphocyte ratio cut-off value was 2.62, based on receiver operating characteristic curve analysis. In multivariate analysis, a higher preoperative neutrophil-lymphocyte ratio (HR = 3.49 95% CI 1.05-11.7; P = 0.042) and 2017 World Health Organization classification (HR = 8.81, 95% CI 1.46-168.2; P = 0.015) were independent recurrence predictors. CONCLUSIONS: The circulating/systemic neutrophil-lymphocyte ratio is a useful and convenient preoperative prognostic marker of recurrence in patients with well-differentiated pancreatic neuroendocrine neoplasm based on the 2017 World Health Organization classification.

[Reconstruction of Portal Vein and Superior Mesenteric Vein Using Superficial Femoral Vein Graft in Surgical Resection of Pancreatic Head Cancer-A Case Report].

We report a case of reconstruction of the portal vein(PV)and superior mesenteric vein(SMV)using a superficial femoral vein graft in total pancreatectomy for pancreatic cancer. A 62-year-old man visited a previous hospital due to epigastric pain and bilirubinuria and was diagnosed with pancreatic cancer. The patient was referred to our hospital for further examination and treatment. Abdominal CT scan revealed a 30 mm pancreatic head tumor with an abutment of almost 360 degrees around the superior mesenteric artery(SMA)and extensive involvement from the PV to branches of the SMV, radiologically classified as locally advanced unresectable pancreatic cancer. Although gemcitabine plus nab-paclitaxel combination therapy(GnP)was performed, the patient developed drug-induced lung injury after 3 courses. GnP was stopped, and chemoradiation therapy with S-1 was performed. After chemoradiation therapy, the tumor shrank to 14 mm, while no change of the abutment around SMA was observed. After 8 months from the initial diagnosis, total pancreatectomy and resection of the PV/SMV were performed. Approximately 70 mm of the PV/SMV was surgically removed and was reconstructed using a graft from the left superficial femoral vein in consideration of the length and diameter. Although delayed gastric emptying was postoperatively observed, the patient was discharged 39 days after operation, then received adjuvant therapy with S-1. The patient is alive without recurrence and the patency of PV/SMV was well maintained.

[A Successful Case of Pancreaticoduodenectomy after Neoadjuvant Therapy for Pancreatic Head Cancer with Acute Pancreatitis Due to Iatrogenic Injury of the Pancreatic Duct].

A 64-year-old woman was referred to our hospital for treatment of pancreatic head cancer with acute pancreatitis due to iatrogenic injury of the pancreatic duct during endoscopic retrograde cholangiopancreatography. In addition to a 28 mm pancreatic head tumor, soft tissue shadow and fluid collection surrounding the superior mesenteric artery(SMA)due to pancreatitis were observed in the abdominal CT scan. The tumor was histologically diagnosed as adenocarcinoma by endoscopic ultrasound-guided fine needle aspiration. Neoadjuvant chemotherapy with gemcitabine and S-1 was performed to control the progression of the pancreatic cancer and improve the inflammatory changes for reduction of the operative risk. After 2 courses of neoadjuvant chemotherapy, abdominal CT scan revealed stable disease according to the Response Evaluation Criteria in Solid Tumors and attenuation of the inflammatory changes surrounding the SMA. Then, subtotal stomach- preserving pancreaticoduodenectomy was performed without the difficulty of peeling around the SMA in spite of the old inflammatory changes. Histological examination of the resected specimen showed R0 resection. The patient was discharged 18 days after surgery without any complications and is surviving 9 months postoperatively without any recurrence. Neoadjuvant chemotherapy was helpful for disease control and improvement of the inflammatory changes.

Prognostic impact of intraoperative peritoneal cytology after neoadjuvant therapy for potentially resectable pancreatic cancer.

BACKGROUND: Neoadjuvant therapy (NAT) is considered a potential approach to improve survival for patients with pancreatic adenocarcinoma (PA). The objective of this study was to identify the clinical implications of washing peritoneal cytology (CY) status after NAT. METHODS: Between 2005 and 2016, 151 consecutive patients with resectable (R)/borderline resectable (BR) PA underwent NAT with intention of subsequent resection at our institution. Of them, 13 and 123 patients underwent pancreatectomies with positive (CY+) and negative (CY-) cytology, respectively, while the remaining 15 patients did not undergo resection due to gross metastases at laparotomy. The clinicopathological factors influencing overall survival were clarified by the uni- and multivariate analyses. RESULTS: The postoperative overall survival (OS) and disease-free survival (DFS) were markedly worse in patients who underwent resection with CY+, compared with those who were CY- (median OS, 14.8 m vs 30.8 m, p = 0.026, and median DFS 6.0 m vs 15.1 m, p = 0.008). According to the resectability by NCCN guidelines, CY+ indicates worse prognosis than CY- in R-PA patients (mOS: 30.1 m vs 71.1 m: p = 0.080). Similarly, in BR-PA patients, CY+ showed the significantly worse prognosis than CY- (mOS: 13.8 m vs 24.5 m: p = 0.048), which prognosis is comparable with patients who did not undergo resection. The multivariate analysis revealed that resectability, CY status and the induction of adjuvant therapy were significant predictors of postoperative OS (p = 0.007: Hazard ratio 2.264, 0.040:2.094 and 0.002:3.246, respectively). CONCLUSIONS: CY+ is a significant predictor of poorer prognosis in PA patients after NAT. The subsequent pancreatectomies with CY+ after NAT do not contribute to prolonged survival.

The superior approach with the stomach roll-up technique improves intraoperative outcomes and facilitates learning laparoscopic distal pancreatectomy: a comparative study between the superior and inferior approach.

PURPOSE: We introduced a superior approach and a unique technique to retract the stomach, called the "stomach roll-up technique", to standardize laparoscopic distal pancreatectomy and increase educational effectiveness. The aim of this study was to evaluate the clinical outcomes of these procedures. METHODS: Forty-five patients who underwent laparoscopic distal pancreatectomy by surgeons-in-training between January 2015 and December 2018 were included. Twenty laparoscopic distal pancreatectomies were performed using the inferior approach, and 25 procedures were performed using the superior approach. The stomach roll-up technique was used in all cases. The perioperative outcomes were retrospectively analyzed. RESULTS: Compared with the inferior approach, the superior approach was associated with a significantly shorter operation time (p < 0.001) and lower estimated blood loss (p = 0.011), and these differences were not affected by the exclusion of cases with conversion or concomitant procedures. In the univariate analysis adjusted for other covariates, a lower body mass index (p = 0.045), pancreatic tail tumor (p = 0.0178) and the superior approach (p = 0.0176) were significantly associated with a shorter operation time. CONCLUSION: The superior approach with the stomach roll-up technique is simple and will aid in educating surgeons on performing laparoscopic distal pancreatectomy.

Gemcitabine combined with docetaxel precisely regressed a recurrent leiomyosarcoma peritoneal metastasis in a patient-derived orthotopic xenograft (PDOX) model.

There are no effective treatments for leiomyosarcoma (LMS) spreading intraabdominally. The aim of this study was to develop precision chemotherapy for recurrent peritoneal LMS metastases in a patient-derived orthotopic xenograft (PDOX) model. The LMS PDOX models were established orthotopically on the dome of the bladder of nude mice. The LMS PDOX models were randomized into 6 groups when the tumor volume reached 80 mm3: G1: untreated control; G2: doxorubicin (DOX) (DOX: i.p., 3 mg/kg, weekly, 3 weeks); G3: DOX combined with olaratumab (OLA) (DOX: i.p., 3 mg/kg, weekly, 3 weeks; OLA: i.p., 40 mg/kg, 3 times/week, 3 weeks); G4: gemcitabine (GEM) combined with docetaxel (DOC) (GEM: i.p., 100  mg/kg, weekly, 3 weeks; DOC: i.p., 20  mg/kg, weekly, 3 weeks); G5: pazopanib (PAZ) (PAZ: p.o., 100  mg/kg, daily, 3 weeks); G6: palbociclib (PAL) (PAL: p.o., 100  mg/kg, daily, 3 weeks). All mice were sacrificed on day 22. Body weight was assessed twice a week. Tumor volume was measured on day 0 and day 22. Although all regimens had a significant efficacy compared to the untreated group (P < 0.001), only GEM combined with DOC regressed the tumor significantly (P < 0.001), suggesting GEM combined with DOC has clinical potential for this LMS patient.

A patient-derived orthotopic xenograft (PDOX) nude-mouse model precisely identifies effective and ineffective therapies for recurrent leiomyosarcoma.

Leiomyosarcoma is a rare and recalcitrant disease. Doxorubicin (DOX) is usually considered first-line treatment for this disease, but frequently is ineffective. In order to individualize therapy for this and other cancers, we have developed the patient-derived orthotopic xenograft (PDOX) mouse model. In the present study, we implanted a recurrent leiomyosarcoma from a resected tumor from the patient's thigh into the femoral muscle of nude mice. The following drugs were tested on the leiomyosarcoma PDOX model: DOX, the combination of gemcitabine (GEM) and docetaxel (DOC), trabectedin (TRA), temozolomide (TEM), pazopanib (PAZ) and olaratumab (OLA). Of these agents GEM/DOC, TRA and TEM were highly effective in the leiomyosarcoma PDOX model, the other agents, including first-line therapy DOX, were ineffective. Thus the leiomyosarcoma PDOX model could precisely distinguish effective and ineffective drugs, demonstrating the potential of the PDOX model for leiomyosarcoma treatment.

Tumor-targeting Salmonella typhimurium A1-R overcomes nab-paclitaxel resistance in a cervical cancer PDOX mouse model.

PURPOSE: Cervical cancer is a recalcitrant disease. To help overcome this problem, we previously established a patient-derived orthotopic xenograft (PDOX) model of cervical cancer. In the previous study, we found the tumor to be resistant to nab-paclitaxal (nab-PTX). We also previously developed the tumor-targeting bacteria Salmonella typhimurium A1-R (S. typhimurium A1-R). The aim of the present study was to investigate the efficacy of S. typhimurium A1-R to overcome nab-PTX resistance in the cervical cancer PDOX model. METHODS: Cervical-cancer tumor fragments were implanted orthotopically into the neck of the uterus of nude mice. The cervical-cancer PDOX models were randomized into the following four groups after the tumor volume reached 60 mm3: G1: untreated group; G2: nab-PTX (i.v., 10 mg/kg, biweekly, 3 weeks); G3: Salmonella typhimurium A1-R (i.v., 5 × 107 CFU/body, weekly, 3 weeks); G4: nab-PTX combined with Salmonella typhimurium A1-R (nab-PTX, 10 mg/kg, i.v., biweekly, 3 weeks; S. typhimurium A1-R, 5 × 107 CFU/body, i.v., weekly, 3 weeks). Each group comprised eight mice. All mice were sacrificed on day 22. Tumor volume was measured on day 0 and day 22. Body weight was measured twice a week. RESULTS: Nab-PTX and Salmonella typhimurium A1-R did not show significant efficacy as monotherapy compared to the control group (P = 0.564 and P = 0.120, respectively). In contrast, nab-PTX combined with Salmonella typhimurium A1-R significantly suppressed tumor growth compared to the untreated control group and nab-PTX group (P < 0.001 and P = 0.026, respectively). CONCLUSIONS: Salmonella typhimurium A1-R has potential future clinical application to overcome drug resistance in cervical cancer.

[Conversion Surgery for Locally Advanced Unresectable Pancreatic Cancer Treated with FOLFIRINOX Therapy and Proton Beam Therapy Combined with S-1 Chemotherapy-A Case Report].

We report a case of locally advanced unresectable(UR-LA)pancreatic cancer in a patient who underwent conversion surgery after FOLFIRINOX and proton beam therapy(PBT)combined with S-1. A 68-year-old woman was referred to our hospital for a pancreatic tumor. The abdominal CT scan revealed a 40mm pancreatic body tumor with an abutment(>180°) of the celiac artery and the superior mesenteric artery. Moreover, the tumor was classified as UR-LA with a contact to the abdominal aorta. The tumor was histologically diagnosed as adenocarcinoma via an endoscopic ultrasound-guided fine-nee- dle aspiration. After 2 courses of FOLFIRINOX, PBT(50 GyE/25 Fr)combined with S-1 were administered. The tumor shrunk to 30mm at the CT scan. After 5 courses of FOLFIRINOX, the tumor reduced to 20 mm. No distant metastasis or malignant cells in abdominal washing cytology was detected using staging laparoscopy. Then, distal pancreatectomy with celiac axis resection(DP-CAR)was performed. According to the General Rules for the Study of Pancreatic Cancer(7th edition)from Japan Pancreas Society, the histological findings were suggestive of ypT3, ypN0, R0, and Grade 3 histological effect. The patient had a Grade A delayed gastric emptying post-operation. He was discharged 35 days after the surgery and has been alive without recurrence on imaging for 11 months post-operation.

Temozolomide regresses a doxorubicin-resistant undifferentiated spindle-cell sarcoma patient-derived orthotopic xenograft (PDOX): precision-oncology nude-mouse model matching the patient with effective therapy.

Undifferentiated spindle-cell sarcoma (USCS) is a recalcitrant cancer, resistant to conventional chemotherapy. A patient with high-grade USCS from a striated muscle was implanted orthotopically in the right biceps femoris muscle of mice to establish a patient-derived orthotopic xenograft (PDOX) model. The PDOX models were randomized into the following groups when tumor volume reached 100 mm3 : G1, control without treatment; G2, doxorubicin (DOX) (3 mg/kg, intraperitoneal [i.p.] injection, weekly, for 2 weeks); G3, temozolomide (TEM) (25 mg/kg, p.o., daily, for 14 days). Tumor size and body weight were measured with calipers and a digital balance twice a week. TEM significantly inhibited tumor volume growth compared to the untreated control and the DOX-treated group on day 14 after treatment initiation: control (G1): 343 ± 78 mm3 ; DOX (G2): 308 ± 31 mm3 , P = 0.272; TEM (G3): 85 ± 21 mm3 , P < 0.0001. TEM significantly regressed the tumor volume compared to day 0 (P = 0.019). There were no animal deaths in any group. The body weight of treated mice was not significantly different in any group. Tumors treated with DOX were comprised of spindle-shaped viable cells without apparent necrosis or inflammatory changes. In contrast, tumors treated with TEM showed extensive tumor necrosis. The present study demonstrates the potential power of matching the patient with an effective drug and saving the patient needless toxicity from ineffective drugs.

Tumor-targeting Salmonella typhimurium A1-R arrests a doxorubicin-resistant PDGFRA-amplified patient-derived orthotopic xenograft mouse model of pleomorphic liposarcoma.

Pleomorphic liposarcoma (PLPS) is a recalcitrant soft-tissue sarcoma (STS) subtype in need of transformative therapy. We have previously established a patient-derived orthotopic xenograft (PDOX) model, of PLPS with PDGFRA amplification, using surgical orthotopic implantation. In the current study, the PLPS PDOX model was randomized into 3 groups of 7 mice each: untreated control; doxorubicin (DOX)-treated; and treated with Salmonella typhimurium A1-R (S. typhimurium A1-R) expressing green fluorescent protein (GFP). Tumor volume and body weight were monitored during the treatment period. The PLPS PDOX was resistant to DOX. In contrast, the PLPS PDOX was highly sensitive to S. typhimurium A1-R. There was no significant body-weight loss among these 3 groups. Fluorescence imaging demonstrated that S. typhimurium A1-R-GFP was very effective to target the PLPS PDOX tumor. The current study demonstrates that a PLPS PDOX, resistant to first-line therapy DOX, was highly sensitive to tumor targeting S. typhimurium A1-R.

Eribulin regresses a doxorubicin-resistant Ewing's sarcoma with a FUS-ERG fusion and CDKN2A-deletion in a patient-derived orthotopic xenograft (PDOX) nude mouse model.

Ewing's sarcoma is a recalcitrant tumor greatly in need of more effective therapy. The aim of this study was to determine the efficacy of eribulin on a doxorubicin (DOX)-resistant Ewing's sarcoma patient derived orthotopic xenograft (PDOX) model. The Ewing's sarcoma PDOX model was previously established in the right chest wall of nude mice from tumor resected form the patient's right chest wall. In the previous study, the Ewing's sarcoma PDOX was resistant to doxorubicin (DOX) and sensitive to palbociclib and linsitinib. In the present study, the PDOX models were randomized into three groups when the tumor volume reached 60 mm3 : G1, untreated control (n = 6); G2, DOX treated (n = 6), intraperitoneal (i.p.) injection, weekly, for 2 weeks); G3, Eribulin treated (n = 6, intravenous (i.v.) injection, weekly for 2 weeks). All mice were sacrificed on day 15. Changes in body weight and tumor volume were assessed two times per week. Tumor weight was measured after sacrifice. DOX did not suppress tumor growth compared to the control group (P = 0.589), consistent with the previous results in the patient and PDOX. Eribulin regressed tumor size significantly compared to G1 and G2 (P = 0.006, P = 0.017) respectively. No significant difference was observed in body weight among any group. Our results demonstrate that eribulin is a promising novel therapeutic agent for Ewing's sarcoma.

Growth of doxorubicin-resistant undifferentiated spindle-cell sarcoma PDOX is arrested by metabolic targeting with recombinant methioninase.

Undifferentiated spindle-cell sarcoma (USCS) is a recalcitrant -cancer in need of individualized therapy. A high-grade USCS from a striated muscle of a patient was grown orthotopically in the right biceps femoris muscle of nude mice to establish a patient-derived orthotopic xenograft (PDOX) model. In a previous study, we evaluated the efficacy of standard first-line chemotherapy of doxorubicin (DOX), gemcitabine (GEM) combined with docetaxel (DOC), compared to pazopanib (PAZ), a multi-targeting tyrosine-kinase inhibitor, in an USCS PDOX model. In the present study, mice-bearing the USCS PDOX tumors were randomized into the following groups when tumor volume reached 100 mm3 : G1, untreated control without treatment; G2, DOX (3 mg/kg, intraperitoneal (i.p.) injection, weekly, for 2 weeks); G3, L-methionine α-deamino-γ-mercaptomethane lyase (recombinant methioninase [rMETase]) (100 U/mouse, i.p., daily, for 2 weeks). Tumor size and body weight were measured with calipers and a digital balance twice a week. The methionine level of supernatants derived from sonicated tumors was also measured. rMETase inhibited tumor growth, measured by tumor volume, compared to untreated controls and the DOX-treated group on day 14 after initiation of treatment: control (G1): 347.6 ± 88 mm3 ; DOX (G2): 329.5 ± 79 mm3 , P = 0.670; rMETase (G3): 162.6 ± 51 mm3 , P = 0.0003. The mouse body weight of the treated mice was not significantly different from the untreated controls. Tumor L-methionine levels were reduced after the rMETase-treatment compared to untreated control and pre-rMETase treatment. We previously reported efficacy of rMETase against Ewing's sarcoma and melanoma in a PDOX models. These studies suggest clinical development of rMETase, especially in recalcitrant cancers such as sarcoma.

Tumor-targeting Salmonella typhimurium A1-R is a highly effective general therapeutic for undifferentiated soft tissue sarcoma patient-derived orthotopic xenograft nude-mouse models.

Undifferentiated soft tissue sarcoma (USTS) is a recalcitrant and heterogeneous subgroup of soft tissue sarcoma with high risk of metastasis and recurrence. Due to heterogeneity of USTS, there is no reliably effective first-line therapy. We have generated tumor-targeting Salmonella typhimurium A1-R (S. typhimurium A1-R), which previously showed strong efficacy on single patient-derived orthotopic xenograft (PDOX) models of Ewing's sarcoma and follicular dendritic cell sarcoma. In the present study, tumor resected from 4 patients with a biopsy-proven USTS (2 undifferentiated pleomorphic sarcoma [UPS], 1 undifferentiated sarcoma not otherwise specified [NOS] and 1 undifferentiated spindle cell sarcoma [USS]) were grown orthotopically in the biceps femoris muscle of mice to establish PDOX models. One USS model and one UPS model were doxorubicin (DOX) resistant. One UPS and the NOS model were partially sensitive to DOX. DOX is first-line therapy for these diseases. S. typhimurium A1-R arrested tumor growth all 4 models. In addition to arresting tumor growth in each case, S. typhimurium A1-R was significantly more efficacious than DOX in each case, thereby surpassing first-line therapy. These results suggest that S. typhimurium A1-R can be a general therapeutic for USTS and possibly sarcoma in general.