CircAGFG1 absence decreases PKM2 expression to enhance oxaliplatin sensitivity in colorectal cancer in a miR-7-5p-dependent manner

Circular RNA (circRNA) ArfGAP with FG repeats 1 (circAGFG1) contributes to colorectal cancer (CRC) development. However, whether circAGFG1 regulates the resistance of CRC to oxaliplatin (L-OHP) remains unknown. CircAGFG1, microRNA-7-5p (miR-7-5p) and pyruvate kinase M2 (PKM2) RNA expression were quantified by quantitative real-time polymerase chain reaction. Protein expression was detected by western blot assay and immunohistochemistry assay. Glycolysis was analyzed through glucose uptake, lactate production and adenosine triphosphate (ATP) concentration assays. 50% inhibitory concentration of L-OHP was determined by cell counting kit-8 assay. Cell proliferation and apoptotic rate were analyzed by cell colony formation and flow cytometry analysis, respectively. Dual-luciferase reporter assay was used to identify the relationship among circAGFG1, miR-7- 5p and PKM2. The effect of circAGFG1 on L-OHP sensitivity in vivo was further evaluated by a xenograft model assay. CircAGFG1 and PKM2 expression were significantly increased, while miR-7-5p was decreased in L-OHP-resistant CRC tissues and cells. High circAGFG1 expression predicted a poor prognosis of CRC. CircAGFG1 knockdown or PKM2 depletion decreased glycolysis and cell proliferation and increased L-OHP sensitivity and cell apoptosis. PKM2 introduction rescued circAGFG1 silencing-induced effects in CRC cells. In terms of mechanism, circAGFG1 bound to miR-7-5p, which was identified to target PKM2. Also, circAGFG1 regulated PKM2 expression by interacting with miR-7-5p. Further, circAGFG1 knockdown improved the sensitivity of tumors to L-OHP in vivo. CircAGFG1 depletion inhibited L-OHP resistance by regulating the miR-7-5p/PKM2 pathway.

Ozone attenuates chemotherapy-induced peripheral neuropathy via upregulating the AMPK-SOCS3 axis

Background

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe adverse reaction to chemotherapeutics, which seriously affects the outcome of chemotherapy and patients' quality of life. Although it is commonly seen, it lacks effective treatment. Our previous study found that ozone could alleviate neuropathic pain. Damage-associated molecular patterns (DAMPs) or Toll-like receptor 4 (TLR4) or tissue factor (TF)-mediated neuroinflammation and microcirculation disturbance is the main reason for CIPN. Suppressors of cytokine signaling (SOCS) 3 is an endogenous negative feedback regulator of inflammation via TLR4 inhibition.

Materials and Methods

Oxaliplatin (L-OHP) was used to establish mice's CIPN model. Nociceptive responses were assessed by observing the ICR mice's incidence of foot regression in mechanical indentation response experiments. Cell signaling assays were performed by Western blotting and immunohistochemistry. The mouse leukemia cells of monocyte-macrophage line RAW 264.7 were cultured to investigate the effects of ozone administration on macrophage.

Results

Ozone decreased the expression of TF in the blood and sciatic nerve. It upregulated the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)-SOCS3 axis to relieve CIPN and inhibit TF expression in vivo. SOCS3 expression was induced by ozone to inhibit the p38/TF signaling in RAW 246.7 cells. Ozone also prevented L-OHP-induced sciatic nerve demyelination. Microglia activation was inhibited, and c-Fos and calcitonin gene-related peptide (CGRP) expression was decreased in the spinal dorsal horn via ozone.

Conclusions

In this study, we demonstrated that ozone could alleviate CIPN by upregulating the AMPK-SOCS3 axis to inhibit TF expression, which is a potential treatment for CIPN.

The role of autophagy in the treatment of colon cancer by chlorin e6 photodynamic therapy combined with oxaliplatin

BACKGROUND

Photodynamic therapy is a tumour treatment method. Its mechanism mainly induces apoptosis, autophagy, and other ways to cause cell death. Therefore, this study aims to evaluate the therapeutic effect of chlorine e6 photodynamic therapy (Ce6-PDT) combined with oxaliplatin (L-OHP) in colon cancer and to investigate the role of autophagy in L-OHP treatment and Ce6-PDT combined with L-OHP in colon cancer.

METHODS

CCK-8 assay, Scratch wound healing assay, and Western Blot (WB) were used to identify drug-resistant colon cancer cell line SW620/L-OHP. Annexin V/FITC assay, laser confocal double immunofluorescence staining method and WB were employed to investigate the apoptosis and autophagy changes in Ce6-PDT combined with L-OHP.

RESULTS

Drug resistance cells SW620/L-OHP were developed under the continuous multi-generation of L-OHP treatment, and the expression of ATP-binding cassette subfamily B member 1 (ABCB1) and ATG5 proteins were increased. The results of immunofluorescence showed that LC3B accumulated in SW620 cells and SW620/L-OHP cells under the treatment of L-OHP. The WB results indicated that LC3B and ATG5 protein expression was increasing in SW620 cells and SW620/L-OHP cells. Inhibition of L-OHP-induced autophagy reduces SW620 cells and SW620/L-OHP cells' viability while increasing apoptosis and the Pro Caspase-3 protein expression. The combination of Ce6-PDT and L-OHP decreased the cell viability, the cell migration ability, the Bcl-2 protein expression, and increased the apoptosis rate, Pro Caspase-3 protein expression in SW620 cells.

CONCLUSIONS

L-OHP can cause SW620 cells drug resistance. Autophagy plays a protective role in the L-OHP treatment of SW620 cells and SW620/L-OHP cells, and inhibition of autophagy can increase the efficacy of L-OHP. Ce6-PDT combined with L-OHP can further improve the tumor's therapeutic effect, and autophagy inhibition can improve the efficacy of combined therapy.

LncRNA CYTOR drives L-OHP resistance and facilitates the epithelial-mesenchymal transition of colon carcinoma cells via modulating miR-378a-5p/SERPINE1

Long non-coding RNAs (lncRNAs) play a vital regulatory role in many human cancers. However, their underlying effect and molecular mechanism in chemoresistance need to be fully researched. This study found that lncRNA CYTOR expression was significantly up-regulated in colon carcinoma tissue and cells. Silencing lncRNA CYTOR in vitro facilitated L-OHP sensitivity of colon carcinoma cells and restrained epithelial-mesenchymal transition (EMT). Furthermore, lncRNA CYTOR could inhibit miR-378a-5p expression, while suppressing miR-378a-5p could attenuate the inhibition of lncRNA CYTOR silencing on L-OHP resistance and EMT. The downstream target mRNA of miR-378a-5p was further explored, and it was discovered that miR-378a-5p restrained SERPINE1 expression. Rescue assay indicated that overexpressing miR-378a-5p or silencing SERPINE1 expression counteracted the promotion of lncRNA CYTOR overexpression on L-OHP resistance and EMT of colon carcinoma cells. In vivo experiment exhibited that silencing lncRNA CYTOR repressed colon carcinoma growth, while miR-378a-5p inhibition diminished the suppression of silencing lncRNA CYTOR on colon carcinoma. These results testified that lncRNA CYTOR enhanced L-OHP drug resistance and induced EMT in colon carcinoma. It was also suggested that lncRNA CYTOR/miR-378a-5p/SERPINE1 axis was a regulatory pathway of L-OHP resistance in colon carcinoma. They could be potential therapeutic targets and prognostic biomarkers.Abbreviations: ATG: autophagy related; EPG: ectopic PGL granules; GFP: green fluorescent protein; LGG-1: LC3, GABARAP and GATE-16 family; LPLA-2: lysosomal phospholipase A2; PGL: P granule abnormality protein; PLA2: phospholipase A2; SD: standard deviation; SEPA-1: suppressor of ectopic P granules in autophagy mutant; SQST-1: sequestosome related.

S-1 and oxaliplatin versus tegafur-uracil and leucovorin as post-operative adjuvant chemotherapy in patients with high-risk stage III colon cancer: updated 5-year survival of the phase III ACTS-CC 02 trial

Background

The ACTS-CC 02 trial demonstrated that S-1 plus oxaliplatin (SOX) was not superior to tegafur-uracil and leucovorin (UFT/LV) in terms of disease-free survival (DFS) as adjuvant chemotherapy for high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries). We now report the final overall survival (OS) and subgroup analysis according to the pathological stage (TNM 7th edition) for treatment efficacy.

Patients and methods

Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m² of UFT and 75 mg/day of LV on days 1-28, every 35 days, five cycles) or SOX (100 mg/m² of oxaliplatin on day 1 and 80 mg/m²/day of S-1 on days 1-14, every 21 days, eight cycles). The primary endpoint was DFS and the patients’ data were updated in February 2020.

Results

A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the final analysis. With a median follow-up time of 74.3 months, the 5-year DFS rate was 55.2% in the UFT/LV group and 58.1% in the SOX group [stratified hazard ratio (HR) 0.92; 95% confidence interval (CI) 0.76-1.11; P = 0.3973], and the 5-year OS rates were 78.3% and 79.1%, respectively (stratified HR 0.97; 95% CI 0.76-1.24; P = 0.8175). In the subgroup analysis, the 5-year OS rates in patients with T4N2b disease were 51.0% and 64.1% in the UFT/LV and SOX groups, respectively (HR 0.72; 95% CI 0.40-1.31).

Conclusion

Our final analysis reconfirmed that SOX as adjuvant chemotherapy is not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer. The 5-year OS rate was similar in the UFT/LV and SOX groups.

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This final analysis reconfirmed that SOX is not superior to UFT/LV in high-risk stage III colon cancer in terms of DFS.

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With a median follow-up time of 74.3 months, the 5-year OS rate was similar in both groups.

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The 5-year OS rates in patients with T4N2b disease were 51.0% and 64.1% in the UFT/LV and SOX groups, respectively.

Role of HOXB7 in promoting gastric cancer progression and oxaliplatin (L-OHP) resistance

BACKGROUND AND AIM

Our study aimed to investigate the ways by which HOXB7 affects gastric cancer progression and oxaliplatin (L-OHP) resistance.

METHODS

First, the expression of HOXB7 in paired cancer and paracancerous tissues of L-OHP-sensitive and L-OHP-resistant gastric cancer patients was qualitatively and quantitatively analyzed by immunohistochemistry. Then, the expression of HOXB7 in these tissues was further quantitatively analyzed at protein and transcriptional levels. The expression of HOXB7 in the SGC-7901 L-OHP-resistant gastric cancer cell line was further verified by immunofluorescence, western blot, and RT-qPCR. In addition, by transfecting the SGC-7901 cell line, control (sh-con) and HOXB-7-silenced (sh-HOXB7) gastric cancer cell lines were created. Subsequently, the migratory and invasive abilities of these cells were determined by the transwell assay. The proliferation rate of both control and HOXB-7-silenced cells induced by varying concentrations of L-OHP was detected by the CCK-8 assay, while the degree of apoptosis in the same cells induced by 60 µM L-OHP was detected by flow cytometry.

RESULTS AND CONCLUSION

Results suggested that HOXB7 was overexpressed in both the tissues of L-OHP-resistant gastric cancer patients and the SGC-7901 gastric cancer cell line. Moreover, HOXB7 promoted the migratory and invasive abilities of gastric cancer cells. By silencing HOXB7 protein expression, the proliferation rate of L-OHP-resistant gastric cancer cells decreased considerably, while their degree of apoptosis increased significantly. These results showed that HOXB7 promoted gastric cancer progression and L-OHP resistance.

S-1 and Oxaliplatin Versus Tegafur-uracil and Leucovorin as Postoperative Adjuvant Chemotherapy in Patients With High-risk Stage III Colon Cancer (ACTS-CC 02): A Randomized, Open-label, Multicenter, Phase III Superiority Trial

BACKGROUND

The efficacy of S-1 plus oxaliplatin (SOX) as postoperative adjuvant chemotherapy for colon cancer has not been established. This randomized phase III study was designed to verify the superiority of SOX over tegafur-uracil and leucovorin (UFT/LV) in patients with high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries).

PATIENTS AND METHODS

Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m² of UFT and 75 mg/day of LV on days 1-28, every 35 days, 5 cycles) or SOX (100 mg/m² of oxaliplatin on day 1 and 80 mg/m² of S-1 on days 1-14, every 21 days, 8 cycles). The primary endpoint was disease-free survival (DFS).

RESULTS

A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the primary analysis. The 3-year DFS was 60.6% (95% confidence interval [CI], 56.0%-64.9%) in the UFT/LV group and 62.7% (95% CI, 58.1%-66.9%) in the SOX group. The stratified hazard ratio for DFS was 0.90 (95% CI, 0.74-1.09; stratified log-rank test, P = .2780). In the N2b subgroup, the 3-year DFS was 46.0% (95% CI, 37.5%-54.0%) in the UFT/LV group and 54.7% (95% CI, 45.7%-62.7%) in the SOX group (hazard ratio, 0.76; 95% CI, 0.55-1.05).

CONCLUSION

As postoperative adjuvant chemotherapy, SOX was not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer.

Hyperthermic intraperitoneal chemotherapy using a combination of mitomycin C,5-fluorouracil, and oxaliplatin in patients at high risk of colorectal peritoneal metastasis: A Phase I clinical study

INTRODUCTION

The drugs and protocols used for hyperthermic intraperitoneal chemotherapy (HIPEC) vary among institutions. Here we show the efficacy of the 3-drug combination of mitomycin C (MMC), 5-fluorouracil (5FU), and oxaliplatin (OHP) in an in vitro simulation of HIPEC and the safety of HIPEC with these drugs during a Phase I study of patients at high risk of developing colorectal peritoneal metastasis.

METHODS

To simulate HIPEC, we used HCT116 and WiDr cells to assess the growth inhibitory efficacy of MMC 2 μg/mL, 5FU 200 μg/mL, and OHP 40 μg/mL as single drugs or their combination after an exposure time of 30 min at 37 or 42 °C. In addition, nine patients underwent surgical resection of tumors and HIPEC with MMC, 5FU, and an escalating dose of OHP (90/110/130 mg/m²). Dose-limiting toxicity was monitored.

RESULTS

In the simulation, the 3-drug combination showed marked tumor-suppressive effects compared with those from ten times higher dose of OHP 400 μg/mL, with significant augmentation under hyperthermic conditions. No dose-limiting toxicity occurred in the clinical study. Dose escalation was completed at the final level of OHP.

CONCLUSIONS

The MMC-5FU-OHP combination showed marked growth inhibition against colorectal cancer cells under hyperthermic conditions in vitro. In the phase I study, the recommended dose of OHP was determined as 130 mg/m² when used with MMC and 5FU; HIPEC using MMC-5FU-OHP appears to be safe and feasible for patients at high risk of colorectal peritoneal metastasis.

Ligand-targeted particulate nanomedicines undergoing clinical evaluation: current status

Since the introduction of Doxil® on the market nearly 20years ago, a number of nanomedicines have become part of treatment regimens in the clinic. With the exception of antibody-drug conjugates, these nanomedicines are all devoid of targeting ligands and rely solely on their physicochemical properties and the (patho)physiological processes in the body for their biodistribution and targeting capability. At the same time, many preclinical studies have reported on nanomedicines exposing targeting ligands, or ligand-targeted nanomedicines, yet none of these have been approved at this moment. In the present review, we provide a concise overview of 13 ligand-targeted particulate nanomedicines (ligand-targeted PNMs) that have progressed into clinical trials. The progress of each ligand-targeted PNM is discussed based on available (pre)clinical data. Main conclusions of these analyses are that (a) ligand-targeted PNMs have proven to be safe and efficacious in preclinical models; (b) the vast majority of ligand-targeted PNMs is generated for the treatment of cancer; (c) contribution of targeting ligands to the PNM efficacy is not unambiguously proven; and (d) targeting ligands do not cause localization of the PNM within the target tissue, but rather provide benefits in terms of target cell internalization and target tissue retention once the PNM has arrived at the target site. Increased understanding of the in vivo fate and interactions of the ligand-targeted PNMs with proteins and cells in the human body is mandatory to rationally advance the clinical translation of ligand-targeted PNMs. Future perspectives for ligand-targeted PNM approaches include the delivery of drugs that are unable or inefficient in passing cellular membranes, treatment of drug resistant tumors, targeting of the tumor blood supply, the generation of targeted vaccines and nanomedicines that are able to cross the blood-brain barrier.