An Update on Colorectal Cancer

Role of ELK1 in regulating colorectal cancer progression: miR-31-5p/CDIP1 axis in CRC pathogenesis

Background and Objective

Colorectal cancer (CRC) is a malignant tumor that affects the digestive system. With the increased of modernization of society, the incidence of colorectal cancer has increased throughout the world. As a transcription factor, ELK1 has been widely studied in colorectal cancer. However, there are still many unknown factors regarding its specific mechanism of action.This study explored the role of ELK1 and its downstream pathway in CRC pathogenesis.

Methods

Based on clinical samples, this study examined miR-31-5p expression in CRC cells and its impact on malignant behaviors (migration, invasion, apoptosis) and autophagy. The promoter sequence of miR-31-5p was obtained from the UCSC database, and ELK1 was identified as its transcription factor. In ELK1-knockdown CRC cells, miR-31-5p was overexpressed, and its response in malignant behaviors and autophagy was analyzed. The target gene CDIP1 was predicted and verified using a dual-luciferase assay. The influence of CDIP1 on malignant behavior in CRC cells was assessed, and CDIP1 siRNA was used as a rescue treatment for miR-31-5p inhibition. The role of ELK1/miR-31-5p in tumor growth was validated in vivo.

Results

miR-31-5p expression was upregulated in the colorectal cancer tissues and cells. The knockdown of miR-31-5p markedly inhibited cancer cells' malignant behaviors and mediated autophagy. ELK1 was confirmed to bind with the miR-31-5p promoter and enhance miR-31-5p transcription. miR-31-5p was found to bind with the CDIP1 3'UTR and inhibit CDIP1 expression. CDIP1 siRNA partially rescued the effects of miR-31-5p knockdown on cell metastatic ability, autophagy, and apoptosis. Based on the in vivo experiments, results showed that the ELK1/miR-31-5p axis positively regulated tumor growth in nude mice.

Conclusion

Our findings indicate that ELK1 regulates the progression of colorectal cancer via an miR-31-5p/CDIP1 axis, and the ELK1/miR-31-5p/CDIP1 axis could be a therapeutic target for colorectal cancer.

Mechanism of Sijunzi Decoction in the treatment of colorectal cancer based on network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Sijunzi Decoction（SJZD）, as a famous classical prescription for the treatment of colorectal cancer(CRC) in the traditional Chinese medicine (TCM), has achieved good curative effects in clinical practice. However, its specific ingredients and molecular mechanisms is still unclear.

AIM OF THE STUDY

To analyze the effective ingredients and molecular mechanisms of SJZD in the treatment of CRC through network pharmacology technology and experimental validation.

MATERIALS AND METHODS

First, the TCM Systems Pharmacology database and analysis platform database were searched to screen the effective chemical components of SJZD. Swiss Target Prediction was used to predict corresponding potential target genes of compounds. After that, we constructed a components and corresponding target network by Cytoscape. Simultaneously, 5 disease databases were used to search and filter CRC targets, and then we constructed a drug-disease target protein-protein interaction (PPI) network. Cytoscape 3.7 was used for visualization and cluster analysis, and Metascape database was used for GO and KEGG enrichment analysis. We drew the main pathway-target network diagram. Autodock vina1.5.6 was applied to molecular docking for the main compounds and target proteins. Subsequently, the potential mechanism of SJZD on colon cancer predicted by network pharmacological analysis was experimentally studied and verified in vivo and in vitro.

RESULTS

144 effective active chemical components, 897 potential targets, and 2584 CRC target genes were screened out. The number of common targets between the SJZD and CRC was 414.3250 GO biological process items and 186 KEGG signal pathways were obtained after analysis. The main compounds and the target protein had a good binding ability in molecular docking. The results of cell and animal experiments showed that SJZD could promote apoptosis and autophagy of CRC cells through PI3K/Akt/mTOR pathway.

CONCLUSIONS

SJZD can treat CRC through multiple components, multiple targets and multiple pathways. We initially revealed the effective components and molecular mechanisms of SJZD in the treatment of CRC, and we used molecular docking and experiment for preliminary verification.

Understanding the Philosophy, Anatomy, and Surgery of the Extra-TME Plane of Locally Advanced and Locally Recurrent Rectal Cancer; Single Institution Experience with International Benchmarking

Simple Summary

Worldwide there is still unwarranted variation in peri-operative management and subsequently oncological outcome following pelvic exenteration for locally advanced and recurrent rectal cancer. The major contributing factor seems to be a difference in treatment strategy with many centres aiming for more neoadjuvant treatment and less radical surgery. However, a radical resection with clear operative margins remains the single most important prognostic factor for survival and therefore an aggressive, radical approach is justified for an optimal oncological outcome and remains the gold standard of care.

Abstract

Pelvic exenteration surgery has become a widely accepted procedure for treatment of locally advanced (LARC) and locally recurrent rectal cancer (LRRC). However, there is still unwarranted variation in peri-operative management and subsequently oncological outcome after this procedure. In this article we will elaborate on the various reasons for the observed differences based on benchmarking results of our own data to the data from the PelvEx collaborative as well as findings from 2 other benchmarking studies. Our main observation was a significant difference in extent of resection between exenteration units, with our unit performing more complete soft tissue exenterations, sacrectomies and extended lateral compartment resections than most other units, resulting in a higher R0 rate and longer overall survival. Secondly, current literature shows there is a tendency to use more neoadjuvant treatment such as re-irradiation and total neoadjuvant treatment and perform less radical surgery. However, peri-operative chemotherapy or radiotherapy should not be a substitute for adequate radical surgery and an R0 resection remains the gold standard. Finally, we describe our experiences with standardizing our surgical approaches to the various compartments and the achieved oncological and functional outcomes.

Zuo Jin Wan Reverses the Resistance of Colorectal Cancer to Oxaliplatin by Regulating the MALAT1/miR-200s/JNK Signaling Pathway

Background

Oxaliplatin (L-OHP) is a common chemotherapy drug used in the treatment of colorectal cancer (CRC). Our previous work showed that Zuo Jin Wan (ZJW), a traditional Chinese medicine prescription, could improve sensitivity to L-OHP in the treatment of CRC, but the detailed mechanism is not clear. In previous mechanistic studies, we found that the miR-200s expression in CRC is associated with L-OHP sensitivity through regulation of MDR1/p-gp and the downstream c-JunN-terminal kinase (JNK) signaling pathway. Moreover, lncRNA-MALAT1 offers great potential in the regulation of drug resistance by interacting with miR-200s. Therefore, in this work, we explored whether ZJW could reverse L-OHP resistance in CRC by regulating MALAT1, miR-200s, and the downstream signaling pathway.

Methods

Cell Counting Kit-8 and flow cytometry were used to detect the effects of ZJW combined with L-OHP on chemotherapy tolerance and cell apoptosis of HCT116/L-OHP cells. Western blotting and quantitative real-time PCR (qRT-PCR) were used to detect the activation of the JNK signaling pathway and the protein and mRNA expression levels of the drug resistance-related MDR1/ABCB1 gene in HCT116/L-OHP cells treated with ZJW. The binding sites of MALAT1 and miR-200s were predicted by bioinformatics tools and confirmed by qRT-PCR. qRT-PCR was used to detect the expression of miR-200s and MALAT1 in HCT116/L-OHP cells treated with ZJW. A xenograft model of CRC in nude mice was established to observe the effect of ZJW combined with L-OHP on the growth of subcutaneously transplanted tumors. Apoptosis in tumor cells was detected by TUNEL staining. The activation of the JNK signaling pathway and the expression of drug resistance-related proteins were detected by immunohistochemistry and immunofluorescence. qRT-PCR was used to detect the expression of miR-200s and the MALAT1 gene in the tumors.

Results

Our study showed that ZJW could significantly decrease the proliferation and promote apoptosis of HCT116/L-OHP cells treated with L-OHP. We further proved that ZJW could reverse the drug resistance of HCT116/L-OHP cells by reducing MALAT1, indirectly upregulating miR-200s, alleviating the activation of the JNK signaling axis, and downregulating the expression of resistance proteins such as MDR1/ABCB1 and ABCG2. ZJW combined with L-OHP inhibited the growth of subcutaneously transplanted tumors and induced apoptosis in nude mice. ZJW reduced the expression of MALAT1 and upregulated the expression of miR-200s in transplanted tumors. In addition, ZJW also alleviated the activation of the JNK signaling pathway while reducing the expression of MDR1/ABCB1 and ABCG2.

Conclusions

Our study identified that MALAT1 promotes colorectal cancer resistance to oxaliplatin by reducing the miR-200s expression. ZJW may reverse chemoresistance by inhibiting the expression of MALAT1 and regulating the miR-200s/JNK pathway, providing an experimental basis for the clinical application of ZJW in relieving chemotherapy resistance.

Propofol Prevents the Growth, Migration, Invasion, and Glycolysis of Colorectal Cancer Cells by Downregulating Lactate Dehydrogenase Both In Vitro and In Vivo

Colorectal cancer (CRC) is one of the most frequently diagnosed gastrointestinal malignancies worldwide and has high rates of morbidity and mortality. Propofol has been reported to have certain anticancer properties. However, the role and mechanism of propofol in CRC are not entirely clear. CRC cells were treated with propofol and/or LDH-overexpression plasmids, and a mouse xenograft model of CRC was also established and treated with propofol. Cell viability, migration, and invasion were evaluated by CCK-8, wound healing, and transwell assays; the expression of related proteins was confirmed by western blotting; indexes of the glycolytic pathway were analyzed using specialized kits; tumor growth in mice was measured; pathological tissue structure was assessed by H&E staining; and 8-OHDG expression was determined by an immunochemistry assay. Our results verified that propofol could effectively prevent the malignant behaviors of CRC cells by suppressing cell viability, migration, and invasion and accelerating apoptosis. We also discovered that propofol could attenuate the glycolytic pathway in CRC cells. Moreover, we proved that lactate dehydrogenase (LDH) was required for the inhibitory effects of propofol on the growth of CRC cells, including glycolysis in CRC cells. Furthermore, our results showed that propofol could not only significantly inhibit tumor growth and glycolysis, but also ameliorate the pathological structure of CRC tumors. The current results proved that propofol could attenuate the malignant progression of CRC by preventing LDH activity, suggesting that propofol might be an effective therapeutic agent for CRC.

LncRNA LINC00460: Function and mechanism in human cancer

Long non-coding RNAs (LncRNAs), which are more than 200 nucleotides in length and with limited protein-coding potential, play vital roles in the pathogenesis, tumorigenesis, and angiogenesis of cancers. Aberrant expression of lncRNAs has been detected in various carcinomas and may be correlated with oncogenesis by affecting related genes expression. Recently, an increasing number of studies have reported on long intergenic non-protein coding RNA 460 (LINC00460) in human tumor fields. LINC00460 is upregulated in diverse cancer tissues and cells. The upregulated expression level of LINC00460 is correlated with larger tumor size, tumor node metastasis (TNM) stage, lymph node metastasis, and shorter overall survival. The regulatory mechanism of LINC00460 was complex and diverse. LINC00460 could act as a competitive endogenous RNA (ceRNA), directly bind with proteins or regulate multiple pathways, which affected tumor progression. Moreover, LINC00460 was also identified to increase drug resistance, and therefore, weaken the effectiveness of tumor treatment. It has become increasingly important to investigate the roles of LINC00460 in various cancers by different mechanisms. Therefore, a more comprehensive understanding of LINC00460 is crucial to expound on the cellular function and molecular mechanism of human cancers. In this review, we refer to studies concerning LINC00460 and provide the basis for the evaluation of LINC00460 as a predicted biomarker or potential therapeutic target in malignancies, and also provide ideas for the future research of lncRNAs similar to LINC00460.

The synergistic effect of chemo-photothermal therapies in SN-38-loaded gold-nanoshell-based colorectal cancer treatment

Aim: 7-Ethyl-10-hydroxycamptothecin (SN-38)-loaded gold nanoshells nanoparticles (HSP@Au NPs) were developed for combined chemo-photothermal therapy to treat colorectal cancer. Materials & methods: SN-38-loaded nanoparticles (HSP NPs) were prepared by the lyophilization-hydration method, and then developed into gold nanoshells. The nanoparticles were characterized and assessed for photothermal properties, cytotoxicity and hemocompatibility in vitro. In vivo anticancer activity was tested in a tumor mouse model. Results: The HSP@Au NPs (diameter 186.9 nm, zeta potential 33.4 mV) led to significant cytotoxicity in cancer cells exposed to a near-infrared laser. Moreover, the HSP@Au NP-mediated chemo-photothermal therapy displayed significant tumor growth suppression and disappearance (25% of tumor clearance rate) without adverse side effects in vivo. Conclusion: HSP@Au NPs may be promising in the treatment of colorectal cancer in the future.

Neoadjuvant chemotherapy in locally advanced colon cancer: a systematic review and meta-analysis

BACKGROUND

There is increasing evidence to support the use of neoadjuvant chemotherapy (NAC) in locally advanced colon cancer (LACC). However, its safety, efficacy and side effect profile is yet to be completely elucidated. This review aims to assess NAC regimens, duration, compare completion rates, intra-operative and post-operative complication profiles and oncological outcomes, in order to provide guidance for clinical practice and further research.

METHODS

PubMed, EMBASE and MEDLINE were searched for a systematic review of the literature from 2000 to 2020. Eight eligible studies were included, with a total of 1213 patients, 752 (62%) of whom received NAC. Of the eight studies analysed, two were randomised controlled trials comparing neoadjuvant chemotherapy followed by oncological resection to upfront surgery and adjuvant chemotherapy, three were prospective single-arm phase II trials analysing neoadjuvant chemotherapy followed by surgery only, one was a retrospective study comparing neoadjuvant chemotherapy followed by surgery versus surgery first followed by adjuvant chemotherapy and the remaining two were single-arm retrospective studies of neoadjuvant chemotherapy followed by surgery.

RESULTS

All cases of LACC were determined and staged by computed tomography; majority of the studies defined LACC as T3 with extramural depth of 5 mm or more, T4 and/or nodal positivity. NAC administered was either folinic acid, fluorouracil and oxaliplatin (FOLFOX) or capecitabine and oxaliplatin (XELOX) with the exception of one study which utilised 5-fluorouracil and mitomycin. Most studies had NAC completion rates of above 83% with two notable exceptions being Zhou et al. and The Colorectal Cancer Chemotherapy Study Group of Japan who both recorded a completion rate of 52%. Time to surgery from completion of NAC ranged on average from 16 to 31 days. The anastomotic leak rate in the NAC group ranged from 0 to 4.5%, with no cases of postoperative mortality. The R0 resection rate in the NAC group was 96.1%. Meta-analysis of both RCTs included in this study showed that neoadjuvant chemotherapy increased the likelihood of a negative resection margin T3/4 advanced colon cancer (pooled relative risk of 0.47 with a 95% confidence interval) with no increase in adverse consequence of anastomotic leak, wound infection or return to theatre.

CONCLUSIONS

Our systematic review and meta-analysis show that NAC is safe with an acceptable side effect profile in the management of LACC. The current data supports an oncological benefit for tumour downstaging and increased in R0 resection rate.

A Systematic Review of the Cyclooxygenase-2 (COX-2) Expression in Rectal Cancer Patients Treated with Preoperative Radiotherapy or Radiochemotherapy

The main objective of this systematic review is to investigate the expression level of the cyclooxygenase-2 (COX-2) in rectal cancer treated with either preoperative radiotherapy or radiochemotherapy. In addition, we have summarized the effects of preoperative treatment of rectal cancer with regards to the expression levels of COX-2. A systematic literature review was performed in The Cochrane Library, PubMed, Web of Science, and Scopus databases on 1 January 2021 with the usage of the following search string-(cyclooxygenase-2) OR (COX-2) AND (rectal cancer) AND (preoperative radiochemotherapy) OR (preoperative radiotherapy). Among the 176 included in the analysis, only 13 studies were included for data extraction with a total number of 2095 patients. The results of the analysis are based on the articles concerning the expression of COX-2 in rectal cancer among patients treated with preoperative radiotherapy or radiochemotherapy. A COX-2 expression is an early event involved in rectal cancer development. In cases of negative COX-2 expression, radiotherapy and radiochemotherapy might contribute to the reduction of a local recurrence. Therefore, COX-2 may be considered as a biologic factor while selecting patients for more effective, less time-consuming and less expensive preoperative treatment. However, the utility of the administration of COX-2 inhibitors to patients with COX-2 overexpression, in an attempt to improve the patients' response rate to the neoadjuvant treatment, needs an assessment in further clinical trials.

A Novel Mechanism of the c-Myc/NEAT1 Axis Mediating Colorectal Cancer Cell Response to Photodynamic Therapy Treatment

Photodynamic therapy (PDT) is considered a potential treatment regimen for colorectal cancer cases (CRC). p53 signaling and the miR-124/iASPP axis play an essential role in the PDT resistance of CRC cells. PDT treatment downregulated NEAT1 expression in p53^wt HCT116 and RKO cells. In these two cell lines, NEAT1 silencing enhanced the suppressive effects of PDT on cell viability and apoptosis. Within the subcutaneously implanted tumor model, NEAT1 silencing enhanced PDT-induced suppression on tumor growth. Regarding p53-deleted HCT116 cells, PDT only moderately affected cell proliferation but induced downregulation of NEAT1. NEAT1 directly targeted miR-124, acting as a ceRNA, competing with iASPP for miR-124 binding, and counteracting miR-124-mediated repression on iASPP under PDT treatment. NEAT1 silencing was enhanced, whereas miR-124 inhibition attenuated PDT effects on CRC cells; miR-124 inhibition significantly reversed the roles of NEAT1 silencing in PDT-treated CRC cells. miR-124 negatively correlated with NEAT1 and iASPP, respectively, whereas NEAT1 and iASPP positively correlated with each other. PDT downregulated c-Myc in CRC cells, and c-Myc activated the transcription of NEAT1 through the targeting of its promoter region. Within p53^mut SW480 cells, PDT failed to alter cell viability and apoptosis but still downregulated c-Myc, NEAT1, and iASPP and upregulated miR-124. In p53 mutant high-abundant CRC tissues, c-Myc and NEAT1 were up-regulated, and miR-124 was downregulated. In c-Myc high-abundant CRC tissues, NEAT1 and iASPP were up-regulated, and miR-124 was downregulated. The critical role of the c-Myc/NEAT1 axis in mediating CRC response to PDT treatment via the miR-124/iASPP/p53 feedback loop was conclusively demonstrated.

Clinical significance of FBXW7 tumor suppressor gene mutations and expression in human colorectal cancer: a systemic review and meta-analysis

BACKGROUND

Various studies investigating the clinical significance of FBXW7 mutation and/or expression have yielded inconclusive results in colorectal cancer (CRC) patients. Therefore, the present meta-analysis summarizes previous evidence and evaluates the clinical significance, including the prognostic role, of FBXW7 status in CRCs.

METHODS

The meta-analysis was conducted by searching the databases of PubMed, China National Knowledge Infrastructure (CNKI), WANFANG data, Web of Science, Embase, and Web of Science. Pooled odds ratios (ORs) and hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated to assess the relationships between FBXW7 status and clinicopathological features and survival in CRC, respectively.

RESULTS

Ten studies involving 4199 patients met the inclusion criteria and included in our meta-analysis. FBXW7 mutation/low expression was obviously correlated with advanced T stage (OR = 0.44, 95% CI: 0.27-0.74, P <  0.01) and lymph node metastasis (OR = 1.88, 95% CI: 1.40-2.53, P <  0.01), but was not associated with other parameters. Further investigation found that FBXW7 mutation/low expression predicted poor OS (HR = 1.25, 95% CI: 1.06-1.47, P <  0.01), but not DFS in CRC (HR = 1.04, 95% CI: 0.60-1.82, P = 0.88). Subgroup analysis found that FBXW7 status was obviously correlated with OS in cohorts recruited after 2009 (HR = 1.32, 95% CI: 1.17-1.50, P <  0.01), from eastern Asia (HR = 1.27, 95% CI: 1.04-1.55, P = 0.02), detected by immunohistochemistry/qRT-PCR (HR = 1.39, 95% CI: 1.22-1.59, P <  0.01), and analysed with multivariate method (HR = 1.47, 95% CI: 1.25-1.74, P <  0.01).

CONCLUSIONS

This study indicates that FBXW7 status, expression level especially, is associated with OS but not DFS in CRC. FBXW7 expression level may function as a prognostic biomarker in CRC.

Dietary Melatonin and Glycine Decrease Tumor Growth through Antiangiogenic Activity in Experimental Colorectal Liver Metastasis

Despite multimodal treatment strategies, clinical outcomes of advanced stage colorectal cancer (CRC) patients remain poor. Neoadjuvant/adjuvant chemotherapy efficacy is limited due to chemoresistance, toxicity, and negative side effects. Since both melatonin and glycine have anti-cancer activities without relevant side effects, this study was designed to investigate their combined effects in experimental CRC liver metastases. CRC metastasis with CC531 cells were induced in male Wistar rats. Melatonin and glycine alone or their combination were supplemented for 14 days (n = 100). Blood parameters, a micro-computed tomography scan (tumor volume over time), and immunohistochemistry for Ki67 and CD31 expression in tumor tissue were compared between groups. Melatonin and glycine alone significantly reduced the tumor volume by 63.2% (p = 0.002) and 43% (p = 0.044) over time, respectively, while tumor volume increased by 8.7% in the controls. Moreover, treatment with melatonin and glycine alone reduced the tumor proliferation index. Most interestingly, the combination therapy did not have any influence on the above-mentioned tumor parameters. The leukocyte count was significantly increased with melatonin at the end of the experiment (p = 0.012) which was due to a high lymphocytes count. Tumor microvascular density was significantly reduced in all treatment groups. The results of this study suggest an inhibitory function for melatonin and glycine alone in the case of CRC liver metastasis growth by acting as natural antiangiogenic molecules, followed by angiogenesis-dependent cancer proliferation and immunomodulation.

Silencing GnT-V reduces oxaliplatin chemosensitivity in human colorectal cancer cells through N-glycan alteration of organic cation transporter member 2

Organic cation transporter member 2 (OCT2) is an N-glycosylated transporter that has been shown to be closely associated with the transport of antitumor drugs. Oxaliplatin, a platinum-based drug, is used for the chemotherapy of colorectal cancer (CRC). However, oxaliplatin resistance is a major challenge in the treatment of advanced CRC. The aim of the present study was to better understand the mechanism underlying the chemosensitivity of CRC cells to oxaliplatin. The present study describes a potential novel strategy for enhancing oxaliplatin sensitivity involving the glycosylation of this drug transporter, specifically the modification of β-1,6-N-acetylglucosamine (GlcNAc) residues by N-acetylglucosaminyltransferase V (GnT-V). The results revealed that the downregulation of GnT-V inhibited the oxaliplatin chemosensitivity of CW-2 cells. Furthermore, the knockdown of GnT-V caused a marked reduction in the presence of β-1,6-GlcNAc structures on OCT2 and decreased the localization of OCT2 in the cytomembrane, which were associated with a reduced uptake of oxaliplatin in wild-type and oxaliplatin-resistant CW-2 cells. Overall, the study provides novel insights into the molecular mechanism by which GnT-V regulates the chemosensitivity to oxaliplatin, which involves the modulation of the drug transporter OCT2 by N-glycosylation in CRC cells.

Bridging the Gap of Drug Delivery in Colon Cancer: The Role of Chitosan and Pectin Based Nanocarriers System

Colon cancer is one of the most prevalent diseases, and traditional chemotherapy has not been proven beneficial in its treatment. It ranks second in terms of mortality due to all cancers for all ages. Lack of selectivity and poor biodistribution are the biggest challenges in developing potential therapeutic agents for the treatment of colon cancer. Nanoparticles hold enormous prospects as an effective drug delivery system. The delivery systems employing the use of polymers, such as chitosan and pectin as carrier molecules, ensure the maximum absorption of the drug, reduce unwanted side effects and also offer protection to the therapeutic agent from quick clearance or degradation, thus allowing an increased amount of the drug to reach the target tissue or cells. In this systematic review of published literature, the author aimed to assess the role of chitosan and pectin as polymer-carriers in colon targeted delivery of drugs in colon cancer therapy. This review summarizes the various studies employing the use of chitosan and pectin in colon targeted drug delivery systems.

Natural photosensitizers in photodynamic therapy: In vitro activity against monolayers and spheroids of human colorectal adenocarcinoma SW480 cells

Photodynamic Therapy (PDT), is a treatment option for cancer.It involves the photochemical interaction of light, photosensitizer (PS) and molecular oxygen to produce radical species as well as singlet oxygen which induce cell death. Anthraquinones (AQs) have been extensively studied with respect to their UV/Vis absorption characteristics and their photosensitizing properties in photodynamic reactions. We study the photoactivity of different natural AQs (Parietin, Soranjidiol and Rubiadin) in treating monolayers and multicellular tumor spheroids (MCTSs). Rubiadin and soranjidiol were isolated and purified from the stem and leaves of Heterophyllae pustulata, and PTN was from the liquen Teloschistes flavicans by using repeated combination of several chromatographic techniques. Monolayer and spheroids of human colorectal adenocarcinoma SW480 cells were incubated with different concentrations of the AQs and then irradiated at room temperature. 24 h post-PDT cell viability, nuclear morphology and type of cell death were analyzed. We observed that Soranjidiol and Rubiadin showed no significant difference in the photosensitizing ability on monoculture of colon cancer cells (LD₈₀ at 50 μM and 10 J/cm², for both AQs). Nevertheless, for Parietin (PTN) LD₈₀ was achieved at (20 μM using the same light dose (10 J/cm²). The death mechanism induced post-PDT was necrosis by use of Soranjidol and Rubiadin and apoptosis by use of PTN. Furthermore, in MCTSs of 300 and 900 μm, the treatment PTN- PDT produces the greatest cytotoxic effect. The three AQs analyzed could be promising chemotherapeutic candidates as anticancer PDT agents.

Why still in hospital after laparoscopic colorectal surgery within an enhanced recovery programme?

AIM

Enhanced recovery after surgery programmes in elective colorectal surgery have been developed and implemented widely, but a subgroup of patients may still require longer hospital stays than expected. The aim of this study was to identify and describe factors compromising early postoperative recovery by asking 'why is the patient still in hospital today?' after laparoscopic colorectal cancer surgery within an enhanced recovery after surgery programme.

METHOD

Patients undergoing elective laparoscopic colorectal cancer resection were evaluated postoperatively with predefined potential reasons for still being in hospital. The primary outcome was 'reason for still being in hospital' on postoperative day 0-4 and secondarily length of stay with a focus on differences between patients with and without a stoma.

RESULTS

Ninety-six patients having colorectal cancer surgery were included. The median length of stay for the whole group was 3 days (range 1-14). The four dominant causes for patients without a stoma to be in hospital were lack of gastrointestinal function, lack of early mobilization, lack of normal micturition and nausea. Patients with a stoma stayed in hospital due to stoma training, lack of gastrointestinal function, lack of free micturition and a miscellaneous 'others' group.

CONCLUSION

Delayed gastrointestinal function, insufficient mobilization, poor urinary function and stoma care training have been characterized as dominant compromising factors for postoperative recovery. Together with a focus on frailty, future studies should focus on improving early mobilization, prevention and treatment of postoperative urinary retention and improved stoma care training, in order to minimize delay in postoperative recovery and discharge.

Photodynamic Therapy Activity of New Porphyrin-Xylan-Coated Silica Nanoparticles in Human Colorectal Cancer

Photodynamic therapy (PDT) using porphyrins has been approved for treatment of several solid tumors due to the generation of cytotoxic reactive oxygen species (ROS). However, low physiological solubility and lack of selectivity towards tumor sites are the main limitations of their clinical use. Nanoparticles are able to spontaneously accumulate in solid tumors through an enhanced permeability and retention (EPR) effect due to leaky vasculature, poor lymphatic drainage, and increased vessel permeability. Herein, we proved the added value of nanoparticle vectorization on anticancer efficacy and tumor-targeting by 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (TPPOH). Using 80 nm silica nanoparticles (SNPs) coated with xylan-TPPOH conjugate (TPPOH-X), we first showed very significant phototoxic effects of TPPOH-X SNPs mediated by post-PDT ROS generation and stronger cell uptake in human colorectal cancer cell lines compared to free TPPOH. Additionally, we demonstrated apoptotic cell death induced by TPPOH-X SNPs-PDT and the interest of autophagy inhibition to increase anticancer efficacy. Finally, we highlighted in vivo, without toxicity, elevated anticancer efficacy of TPPOH-X SNPs through improvement of tumor-targeting compared to a free TPPOH protocol. Our work demonstrated for the first time the strong anticancer efficacy of TPPOH in vitro and in vivo and the merit of SNPs vectorization.