Adjuvant chemotherapy for rectal cancer: Current evidence and recommendations for clinical practice

A systematic review of population-based studies on metachronous metastases of colorectal cancer

BACKGROUND

The occurrence of metachronous metastases (MM) of colorectal (CRC), colon (CC), and rectal (RC) cancer of population-based studies has not been compiled in a systematic review previously.

METHODS

MEDLINE, Embase, and Cochrane Library were searched for primary studies of any design from inception until January 2021 and updated in August 2023 (CRD42021261648). The PRISMA guidelines were adopted, and the Newcastle-Ottawa Quality Assessment Scale used for risk of bias assessment. Outcomes on overall and organ-specific MM were extracted. A narrative analysis followed.

RESULTS

Out of 2143 unique hits, 162 publications were read in full-text and 37 population-based cohort studies published in 1981-2022 were included. Ten studies adopted time-dependent analyses; eight were registry-based and seven had a low risk of bias. Three studies reported 5-year recurrence rate of MM overall of stages I-III; for CRC, it was 20.5%, for CC, it was 18% and 25.6%, and for RC, it was 23%. Four studies reported 5-year recurrence rate of organ-specific MM of stages I-III-for CRC, it was 2.2% and 5.5% for peritoneal metastases and 5.8% for lung metastases and for CC 4.5% for peritoneal metastases. Twenty-seven studies reported proportions of patients diagnosed with MM, but data on the length of follow-up was incomplete and varied widely. Proportions of patients with CRC stages I-III that developed MM overall was 14.4%-26.1% in 10 studies. In relation to the enrollment period, a downward trend may be discernible.

CONCLUSION

Studies adopting a more appropriate analysis were highly heterogeneous, whereas uncertain data of partly inadequate studies may indicate that MM are overall declining.

Patient management after primary rectal cancer diagnosis. Special focus on surgical treatment for non-metastatic disease

Background: Rectal cancer is a public health priority. Primary objectives of this study were to evaluate the quality of care for non-metastatic rectal cancer using process and outcome indicators. Delay of management, length of stay and readmission rate, sphincter preservation, morbidity, number of examined lymph nodes, mortality, overall and disease-free survivals were evaluated. Secondary objectives were to estimate the relationship between possible predictive parameters for (1) anastomotic leakage (logistic regression), (2) overall or disease-free survivals (cox regression).Methods: We performed a retrospective study on 312 consecutive patients diagnosed with primary rectal cancer between 2016 and 2019. We focused on the 163 patients treated by surgery for non-metastatic cancer.Results: The treatment began within 33 days (range 0-264) after incidence, resection rate was 67%. Digestive continuity rate in lower, middle and upper rectum was 30%, 87% and 96%. Median of 14 lymph nodes (range 1-46) was analyzed. Length of stay and readmission rate were 11 days (range 3-56) and 4%, respectively. Within 90 postoperative days, clinical anastomotic leakage occurred in 9.2% of cases, major morbidity rate was 17%, mortality 1.2%. Multivariate analysis revealed that stoma decreased the risk of anastomotic leakage [hazard ratio: 0.16; 95% confidence intervals: 0.04-0.63; p = 0.008]. The 5-year overall survival after surgery was 85 ± 4%, disease-free survival 83 ± 4%. Patients with major complications, male gender and R1/R2 resection margin had a poorer prognosis.Conclusion: This work showed encouraging results in rectal cancer treatment in our institution, our results were in line with recommendations at the time.

Pathologic Complete Response, Total Neoadjuvant Therapy and the Survival Paradox in Locally Advanced Rectal Cancer

BACKGROUND

Pathologic complete response (pCR) after preoperative chemoradiation (nCRT) correlates with improved overall survival for patients with locally advanced rectal cancers (LARCs). Escalation protocols including total neoadjuvant therapy (TNT), which delivers multi-agent chemotherapy and chemoradiation before surgery, are associated with increased complete response rates. However, TNT is not associated with improved overall survival. The authors hypothesized that the route to pCR may be an important predictor of oncologic outcome.

METHODS

Adults with LARC between 2006 and 2017 were identified in the National Cancer Database. The cohort was limited to those who received neoadjuvant radiation (45-70 Gy) and underwent proctectomy.

RESULTS

Of 25,880 patients, 16 % received TNT and 84 % had nCRT followed by either multi-agent (27 %), single-agent (14 %), or no adjuvant chemotherapy (44 %). Overall, 18 % achieved pCR, with higher rates in the TNT cohort than in the nCRT (18 %) or multi-agent (14 %) chemotherapy cohorts. With control for covariates, the OS in the pCR cohort was similar for the patients that received single-agent therapy and those that received multi-agent adjuvant therapy, and superior to the TNT and no adjuvant therapy cohorts. Conversely, among the patients who did not achieve pCR, those who received single-agent chemotherapy had OS comparable with those who had multi-agent adjuvant therapy and TNT, which was better than no adjuvant therapy.

CONCLUSION

Patients achieving pCR after TNT had worse OS than those who had CRT alone, suggesting that the neoadjuvant route by which pCR is achieved is prognostically relevant. Therefore, in the era of neoadjuvant therapy escalation, pCR does not necessarily portend a uniformly favorable prognosis.

Therapeutic effects of coptisine derivative EHLJ7 on colorectal cancer by inhibiting PI3K/AKT pathway

Colorectal cancer (CRC) is the third most common cancer in the world with high mortality rate. EHLJ7 is a quaternary coptisine derivative synthesized by our institute. In this study, the role and mechanism of EHLJ7 on CRC are further elucidated. Using target fishing, colon cancer-associated target screening and molecular docking analysis, PI3K/AKT pathway was selected for the target of EHLJ7 at CRC. Results of Flow cytometry, wound healing assay and transwell migration assay confirmed that EHLJ7 could inhibit migration and apoptosis of colon cancer cells by specifically inhibiting PI3K/AKT pathway in vitro. Xenograft tumor models and a newly established azoxymethane (AOM)/dextran sulfate sodium (DSS)/Peptostreptococcus anaerobiu (P.anaerobius)-induced CRC mouse model are applied to access the anti-cancer action and mechanism of EHLJ7 using western-blot, immunohistochemistry and analysis of exosomes. The key findings in this study are listed as follows: (1) EHLJ7 exerts superior anti-tumor effect with good safety on Xenograft tumor model and CRC model; (2) EHLJ7 exerted its anti-CRC effect by specifically inhibiting PI3K/AKT pathway and apoptosis in vivo and in vitro. In summary, we demonstrated that EHLJ7 exerts therapeutic effect against CRC by PI3K/AKT pathway, which made it possible as a potentially effective compound for the treatment of CRC.

The role of adjuvant chemotherapy in rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy has emerged as the established treatment for locally advanced rectal cancer. Nevertheless, there remains a debate regarding the necessity of adjuvant chemotherapy for patients with locally advanced rectal cancer who exhibit a favorable tumor response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery. Thus, the objective of this study is to investigate the impact of adjuvant chemotherapy on the oncological prognosis of rectal cancer patients who have a good response to neoadjuvant chemoradiotherapy.

Materials and methods

The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in the Web of Science, PubMed, and Cochrane Library databases. The primary outcomes assessed were 5-year overall survival, disease-free survival, cancer-specific survival, recurrence-free survival, local recurrence, and distant metastasis. The data was summarized using a random effects model.

Results

A meta-analysis was conducted using 18 retrospective studies published between 2009 and 2023. The studies included 9 from China and 5 from Korea, involving a total of 6566 patients with ypT0-2N0 rectal cancer after neoadjuvant chemoradiotherapy. The pooled data revealed that adjuvant chemotherapy significantly improved 5-year overall survival (OR=1.75, 95% CI: 1.15-2.65, P=0.008), recurrence-free survival (OR=1.73, 95% CI: 1.20-2.48, P=0.003), and reduced distant metastasis (OR=0.68, 95% CI: 0.51-0.92, P=0.011). However, adjuvant chemotherapy did not have a significant effect on disease-free survival, cancer-specific survival, and local recurrence in ypT0-2N0 rectal cancer. Subgroup analysis indicated that adjuvant chemotherapy was beneficial in improving overall survival for ypT1-2N0 rectal cancer (OR=1.89, 95% CI: 1.13-3.19, P=0.003).

Conclusion

The findings of the meta-analysis suggest that adjuvant chemotherapy may provide benefits in terms of oncological outcomes for rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy and radical surgery. However, further prospective clinical studies are needed to confirm these findings.

Inositol hexaphosphate enhances chemotherapy by reversing senescence induced by persistently activated PERK and diphthamide modification of eEF2

Oxaliplatin is an important initial chemotherapy benefiting advanced-stage colorectal cancer patients. Frustratingly, acquired oxaliplatin resistance always occurs after sequential chemotherapy with diverse antineoplastic drugs. Therefore, an exploration of the mechanism of oxaliplatin resistance formation in-depth is urgently needed. We generated oxaliplatin-resistant colorectal cancer models by four representative compounds, and RNA-seq revealed that oxaliplatin resistance was mainly the result of cells' response to stimulus. Moreover, we proved persistent stimulus-induced endoplasmic reticulum stress (ERs) and associated cellular senescence were the core causes of oxaliplatin resistance. In addition, we screened diverse phytochemicals for ER inhibitors in silico, identifying inositol hexaphosphate (IP6), whose strong binding was confirmed by surface plasmon resonance. Finally, we confirmed the ability of IP6 to reverse colorectal cancer chemoresistance and investigated the mechanism of IP6 in the inhibition of diphthamide modification of eukaryotic elongation factor 2 (eEF2) and PERK activation. Our study demonstrated that oxaliplatin resistance contributed to cell senescence induced by persistently activated PERK and diphthamide modification of eEF2 levels, which were specifically reversed by combination therapy with IP6.

Acetone compression improves lymph node yield and metastasis detection in colorectal cancer

Lymph node status is one of the most important prognostic factors in colorectal cancer, and accurate pathological nodal staging and detection of lymph node metastases is crucial for determination of post-operative management. Current guidelines, including the TNM staging system and European Society for Medical Oncology (ESMO) guidelines, recommend examination of at least 12 lymph nodes. However, identification of an adequate number of lymph nodes can be challenging, especially in the setting of neoadjuvant treatment, which may reduce nodal size. In this study, we investigated 384 colorectal cancer resections that were processed at our department of pathology between January 2012 and December 2022, in which the number of detected lymph nodes was less than 12 subsequent to conventional preparation of mesocolic fat tissue. By means of acetone compression, lymph node harvest increased significantly (p < 0.0001), and the intended number of ≥ 12 lymph nodes was achieved in 98% of resection specimens. The number of nodal positive cases increased significantly from n = 95 (24.7%) before versus n = 131 (34.1%) after acetone compression due to additionally identified lymph node metastases (p < 0.001). In 36 patients (9.4%) initially considered as nodal negative, acetone compression led to a staging adjustment to a nodal positive category and thereby drove a recommendation to offer post-operative therapy. In conclusion, acetone compression is a reliable and useful method implementable in routine surgical pathology for the retrieval of lymph nodes in colorectal cancer specimen, allowing for an adequate lymph node sampling and an increase in nodal staging reliability.

Novel GSH-responsive prodrugs derived from indole-chalcone and camptothecin trigger apoptosis and autophagy in colon cancer

Antineoplastic agents that target tubulin have shown efficacy as chemotherapeutic drugs, yet they are often constrained by multidrug resistance (MDR) and unwanted side effects. A multi-targeted strategy demonstrates great potency in reducing toxicity and enhancing efficacy and provides an alternative way for attenuating MDR. In this study, a series of dual-targeted anti-cancer agents based on indole-chalcone derivatives and the camptothecin (CPT) scaffold were synthesized. Among them, 14-1 demonstrated superior anti-proliferative activity than its precursor 13-1, CPT or their physical mixtures against tested cancer cells, including multidrug-resistant variants, while exhibited moderate cytotoxicity toward human normal cells. Mechanistic studies revealed that 14-1 acted as a glutathione-responsive prodrug, inducing apoptosis by substantially enhancing intracellular uptake of CPT, inhibiting tubulin polymerization, increasing the accumulation of intracellular reactive oxygen species, and initiating a mitochondrion-dependent apoptotic pathway. Moreover, 14-1 notably induced autophagy and suppressed topoisomerase I activity to further promote apoptosis. Importantly, 14-1 displayed potent inhibitory effect on tumor growth in paclitaxel (PTX)-resistant colorectal cancer (HCT-116/PTX) xenograft models without inducing obvious toxicity compared with CPT- or combo-treated group. These results suggest that 14-1 holds promise as a novel candidate for anti-cancer therapy, particularly in PTX-resistant cancers.

Enlarged tumour-draining lymph node with immune-activated profile predict favourable survival in non-metastatic colorectal cancer

BACKGROUND

The tumour-draining lymph node (TDLN) plays a pivotal role in the suppression of malignant tumour, however, the immunological profile and prognostic differences between large TDLN (L-TDLN) and small TDLN (S-TDLN) in colorectal cancer (CRC) remain unclear.

METHODS

We conducted a study using data from the Chinese National Cancer Center (CNCC) database, identifying 837 CRC patients with non-metastatic TDLN, and categorised them into L-TDLN and S-TDLN groups. The long-term survival outcomes and adjuvant therapy efficacy were compared between the two groups. Furthermore, we evaluated the differences in immune activation status and immune cell subsets between patients in L-TDLN and S-TDLN groups by RNA sequencing and immunohistochemical (IHC) staining.

RESULTS

Patients with L-TDLN demonstrated better long-term outcomes compared to those with S-TDLN. Among patients with L-TDLN, there was no significant difference in long-term outcomes between those who received adjuvant chemotherapy and those who did not. The RNA sequencing data revealed a wealth of immune-activating pathways explored in L-TDLN. Furthermore, IHC analysis demonstrated higher numbers of CD3+ and CD8 + T cells in L-TDLN and the corresponding CRC lesions, as compared to patients with S-TDLN.

CONCLUSION

Enlarged TDLN exhibited an activated anti-tumour immune profile and may serve as an indicator for favourable survival in non-metastatic CRC.

Anxiety and depression during 3-year follow-up period in postoperative gastrointestinal cancer patients: prevalence, vertical change, risk factors, and prognostic value

BACKGROUND

Anxiety and depression are common issues in gastrointestinal cancer, bringing negative impacts on patients' quality of life and long-term prognosis. This study aimed to identify the prevalence, longitudinal variation, risk factors, and prognostic value of anxiety and depression in postoperative gastrointestinal cancer patients.

METHODS

A total of 320 gastrointestinal cancer patients after surgical resection (210 colorectal cancer (CRC) patients and 110 gastric cancer (GC) patients) were enrolled in this study. During the 3-year follow-up period, Hospital Anxiety and Depression Scale (HADS)-anxiety (HADS-A) and HADS-depression (HADS-D) scores were determined at baseline, 12th month (M12), 24th month (M24), and 36th month (M36).

RESULTS

The prevalence of anxiety and depression at baseline was 39.7% and 33.4% in postoperative gastrointestinal cancer patients, respectively. Female (vs. male), single/divorced/widowed (vs. married), CRC (vs. GC), hypertension, higher TNM stage, neoadjuvant chemotherapy, and postoperative complications were independent risk factors of anxiety or depression in patients with gastrointestinal cancer (all P < 0.050). Furthermore, anxiety (P = 0.014) and depression (P < 0.001) were associated with shortened overall survival (OS); after further adjustment, depression was independently linked with shortened OS (P < 0.001), while anxiety was not. During the follow-up period, HADS-A score (from 7.78 ± 3.180 to 8.57 ± 2.854, P < 0.001), HADS-D score (from 7.23 ± 2.711 to 8.01 ± 2.786, P < 0.001), anxiety rate (from 39.7 to 49.2%, P = 0.019), and depression rate (from 33.4 to 42.6%, P = 0.023) were all gradually increased from baseline to M36.

CONCLUSION

Anxiety and depression gradually exacerbate and relate to poor survival in postoperative gastrointestinal cancer patients.

Impact of consolidation chemotherapy in poor responders to neoadjuvant radiation therapy: magnetic resonance imaging-based clinical-radiological correlation in high-risk rectal cancers

PURPOSE

The current study was conducted to examine the role of consolidation chemotherapy after neoadjuvant radiation therapy (NART) in decreasing the involvement of the mesorectal fascia (MRF) in high-risk locally advanced rectal cancers (LARCs).

METHODS

In total, 46 patients who received consolidation chemotherapy after NART due to persistent MRF involvement were identified from a database. A team of 2 radiologists, blinded to the clinical data, studied sequential magnetic resonance imaging (MRI) scans to assess the tumor response and then predict a surgical plan. This prediction was then correlated with the actual procedure conducted as well as histopathological details to assess the impact of consolidation chemotherapy.

RESULTS

The comparison of MRI-based parameters of sequential images showed significant downstaging of T2 signal intensity, tumor height, MRF involvement, diffusion restriction, and N category between sequential MRIs (P < 0.05). However, clinically relevant downstaging (standardized mean difference, > 0.3) was observed for only T2 signal intensity and diffusion restriction on diffusion-weighted imaging. No clinically relevant changes occurred in the remaining parameters; thus, no change was noted in the extent of surgery predicted by MRI. Weak agreement (Cohen κ coefficient, 0.375) and correlation (Spearman rank coefficient, 0.231) were found between MRI-predicted surgery and the actual procedure performed. The comparison of MRI-based and pathological tumor response grading also showed a poor correlation.

CONCLUSION

Evidence is lacking regarding the use of consolidation chemotherapy in reducing MRF involvement in LARCs. The benefit of additional chemotherapy after NART in decreasing the extent of planned surgery by reducing margin involvement requires prospective research.

Integrated analysis of single cell and bulk RNA sequencing identifies CTHRC1+ INHBA+ CAF as drivers of colorectal cancer progression

Cancer-associated fibroblasts (CAFs) are a key component of the tumor microenvironment and a critical factor in the progression of colorectal cancer (CRC). The aim of this study was to screen for CAFs specific genes that could serve as promising therapeutic targets for CRC patients. Our findings showed a significant increase in the proportion of fibroblasts in CRC tissues, and a high proportion of fibroblasts was associated with immune escape and poor prognosis in CRC. Collagen triple helix repeat containing 1 (CTHRC1) and inhibin subunit beta A (INHBA) were identified as key genes in the progression of CRC, primarily expressed in CAFs and significantly upregulated in CRC tissues. We defined CTHRC1 and INHBA as cancer-associated fibroblast-related genes (CAFRGs), which were associated with poor prognosis in CRC and macrophage polarization. CAFRGs promoted immune escape and metastasis in CRC and were good predictors of immune therapy response. Drug sensitivity analysis showed that the high expression group of CAFRGs was sensitive to 15 chemotherapy drugs, while the low expression group was sensitive to only 3. Clustering of fibroblasts in the tumor revealed that CTHRC1+ INHBA+ CAF was a poor prognostic factor in CRC and was associated with extracellular matrix remodeling and immune regulation. In conclusion, our study provides new theoretical basis for effective treatment strategies and therapeutic targets for CRC.

Improving prognosis and assessing adjuvant chemotherapy benefit in locally advanced rectal cancer with deep learning for MRI: A retrospective, multi-cohort study

PURPOSE

Adjuvant therapy is recommended to minimize the risk of distant metastasis (DM) and local recurrence (LR) in patients with locally advanced rectal cancer (LARC). However, its role is controversial. We aimed to develop a pretreatment MRI-based deep learning model to predict LR, DM, and overall survival (OS) over 5 years after surgery and to identify patients benefitting from adjuvant chemotherapy (AC).

MATERIALS AND METHODS

The multi-survival tasks network (MuST) model was developed in a primary cohort (n = 308) and validated using two external cohorts (n = 247, 245). An AC decision tree integrating the MuST-DM score, perineural invasion (PNI), and preoperative carbohydrate antigen 19-9 (CA19-9) was constructed to assess chemotherapy benefits and aid personalized treatment of patients. We also quantified the prognostic improvement of the decision tree.

RESULTS

The MuST network demonstrated high prognostic accuracy in the primary and two external cohorts for the prediction of three different survival tasks. Within the stratified analysis and decision tree, patients with CA19-9 levels > 37 U/mL and high MuST-DM scores exhibited favorable chemotherapy efficacy. Similar results were observed in PNI-positive patients with low MuST-DM scores. PNI-negative patients with low MuST-DM scores exhibited poor chemotherapy efficacy. Based on the decision tree, 14 additional patients benefiting from AC and 391 patients who received over-treatment were identified in this retrospective study.

CONCLUSION

The MuST model accurately and non-invasively predicted OS, DM, and LR. A specific and direct tool linking chemotherapy decisions and benefit quantification has also been provided.

The benefits of adjuvant chemotherapy are associated with the kind of neoadjuvant therapy in stage ypI rectal cancer: evidence based on population analysis

PURPOSE

The oncological role of adjuvant chemotherapy (ACT) remains debated in locally advanced rectal cancer (RC) after neoadjuvant therapy (NAT), especially ypI RC. In this study, we used population-based data to evaluate the benefits of ACT in stage ypI RC after NAT and surgery. Moreover, we tried to differentiate what kind of NAT (radiotherapy alone or chemoradiotherapy) was administered because this may affect the further efficacy of ACT.

METHODS

All patients with stage ypI primary rectal malignancy were diagnosed in the SEER database between 2004 and 2017. The Kaplan-Meier method was applied to estimate the effects of ACT in survival analysis. Cox regression was performed to calculate the hazard ratio (HR) and the prognosis factors of survival. Propensity score matching (PSM) was used to balance the parameters between therapy groups.

RESULTS

The overall cohort's median follow-up time was 105 months. For 5-year OS and CSS, there were no significant differences between the ACT ( +) and ACT (-) groups (p = 0.105; p = 0.788). However, subgroup analyses according to the kind of NAT found that ACT improved overall survival (OS) and cancer-specific survival (CSS) in patients who received neoadjuvant radiotherapy (nRT) (p < 0.001, p = 0.015). Among patients who received neoadjuvant chemoradiotherapy (nCRT), no significant survival benefits were found between the ACT ( +) and ACT (-) groups (p = 0.526, p = 0.288).

CONCLUSION

Our population-based cohort study suggested that the efficacy of ACT was associated with the kind of NAT. The ACT provides survival benefits in stage ypI RC for patients who received nRT. However, among patients who received nCRT, ACT did not improve long-term survival.

Implication of MRI Risk Stratification System on the Survival Benefits of Adjuvant Chemotherapy After Neoadjuvant Chemoradiotherapy in Patients With Locally Advanced Rectal Cancer

RATIONALE AND OBJECTIVES

To investigate the implication of a Magnetic resonance imaging (MRI) risk stratification system on the selection of patients with locally advanced rectal cancer (LARC) who can benefit from adjuvant chemotherapy (ACT) after neoadjuvant chemoradiotherapy (NCRT).

MATERIALS AND METHODS

This retrospective study included 328 patients with LARC who underwent NCRT and surgery. The median follow-up duration was 79 months (Interquartile range, 66-94 months). Cox logistic regression analysis was used to identify MRI risk factors and develop a risk stratification system to stratify patients into groups with high and low risks. Kaplan-Meier curves of distant metastasis-free survival (DMFS) and overall survival (OS) were used to show the benefits of ACT and stratify results based on the MRI risk stratification system and postoperative pathological staging.

RESULTS

An MRI risk stratification system was built based on four MRI risk factors, including MRI-identified T3b-T4 stage, N1-N2 stage, extramural venous invasion, and tumor deposits. 74 (22.6%) patients with 3-4 MRI risk factors were classified into the MRI high-risk group. ACT could significantly improve 5-year DMFS (19.2% versus 52.1%; p < 0.001) and OS (34.6% versus 75.0%; p < 0.001) for patients in the MRI high-risk group, while ACT had no survival benefit for patients in the MRI low-risk group. The benefits of ACT were not observed in patients with any pathological staging subgroups (ypT0-2N0, ypT3-4N0, and ypN+).

CONCLUSION

Patients in the MRI high-risk group could benefit from ACT, regardless of postoperative pathological staging. Baseline MRI should be considered more in ACT decision-making.

Expression of aquaporin 1, 3 and 5 in colorectal carcinoma: correlation with clinicopathological characteristics and prognosis

Background: Prognostic biomarkers in colorectal carcinoma (CRC) have an important role in therapeutic strategy. Studies have shown that high expression of Aquaporin (AQP) is associated with poor prognosis in a variety of human tumors. AQP is involved in the initiation and development of CRC. The present study aimed to investigate the correlation between the expression of AQP1, 3 and 5 and clinicopathological features or prognosis in CRC. Methods: The AQP1, 3 and 5 expressions were analyzed based on the immunohistochemical staining of tissue microarray specimens including 112 patients with CRC between June 2006 and November 2008. The expression score of AQP (Allred_score and H_score) was digitally obtained with Qupath software. Patients were divided into high or low expression subgroups based on the optimal cut-off values. The relationship between expression of AQP and clinicopathological characteristics were evaluated using chi-square test, t-test, or one-way ANOVA, when appropriate. Survival analysis of 5-year progression free survival (PFS) and overall survival (OS) was performed with time-dependent ROC, Kaplan-Meier curves, univariate and multivariate COX analysis. Results: The AQP1, 3 and 5 expressions were associated with regional lymph node metastasis, histological grading, and tumor location in CRC, respectively (p < 0.05). Kaplan-Meier curves showed that patients with high AQP1 expression had worse 5-year PFS than those with low AQP1 expression (Allred_score: 47% vs. 72%, p = 0.015; H_score: 52% vs. 78% p = 0.006), as well as 5-year OS (Allred_score: 51% vs. 75%, p = 0.005; H_score: 56% vs. 80%, p = 0.002). Multivariate Cox regression analysis indicated that AQP1 expression was an independent risk prognostic factor (p = 0.033, HR = 2.274, HR95% CI: 1.069-4.836). There was no significant correlation between the expression of AQP3 and 5 and the prognosis. Conclusion: The AQP1, 3 and 5 expressions correlate with different clinicopathological characteristics and the AQP1 expression may be a potential biomarker of prognosis in CRC.

The use of adjuvant chemotherapy is not associated with recurrence or cancer-specific death following curative resection for stage III rectal cancer: a competing risks analysis

BACKGROUND

The role of adjuvant chemotherapy (AC) in stage III rectal cancer (RC) has been argued based on evidence from its use in colon cancer. Previous trials have analysed disease-free and overall survivals as endpoints, rather than disease recurrence. This study compares the competing risks incidences of recurrence and cancer-specific death between patients who did and did not receive AC for stage III RC.

METHODS

Consecutive patients who underwent a potentially curative resection for stage III RC (1995-2019) at Concord Hospital, Sydney, Australia, were studied. AC was considered following multidisciplinary discussion. Primary outcome measures were the competing risks incidences of disease recurrence and cancer-specific death. Associations between these outcomes and use of AC (and other variables) were tested by regression modelling.

RESULTS

Some 338 patients (213 male, mean age 64.4 years [SD12.7]) were included. Of these, 208 received AC. The use of AC was associated with resection year (adjusted OR [aOR] 1.74, 95%CI 1.27-2.38); age ≥75 years (aOR0.04, 95%CI 0.02-0.12); peripheral vascular disease (aOR0.08, 95%CI 0.01-0.74); and postoperative abdomino-pelvic abscess (aOR0.23, 95%CI 0.07-0.81). One hundred fifty-seven patients (46.5%) were diagnosed with recurrence; death due to RC occurred in 119 (35.2%). After adjustment for the competing risk of non-cancer death, neither recurrence nor RC-specific death was associated with AC (HR0.97, 95%CI 0.70-1.33 and HR0.72, 95%CI 0.50-1.03, respectively).

CONCLUSION

This study found no significant difference in either recurrence or cancer-specific death between patients who did and did not receive AC following curative resection for stage III RC.

Global Status of Research on Lateral Lymph Nodes in Rectal Cancer from 1994 to 2022: A Bibliometric Analysis

Tremendous progress has been made in the field of lateral lymph nodes (LLNs) in rectal cancer, but no bibliometric analysis in this field has been carried out and published. To reveal the current status and trends in LLNs in rectal cancer, this bibliometric analysis was performed. Cooperation network, co-citation and keyword co-occurrence analyses were conducted. Annual publication, cooperation relationships among authors, institutions and countries, co-cited journal, co-cited author, co-cited reference and keywords were the main outcomes. A total of 345 studies were included in this bibliometric analysis. The number of articles published in this field has been increasing year by year. The authors, institutions and countries worked closely together in this field. Japan has the largest number of published articles, accounting for 51.59% of the total publications. International Journal of Colorectal Disease (30 papers, 8.70%) published the most papers in this field. The JCOG0212 trial was the most cited article. Preoperative chemoradiotherapy, multicenter, lateral lymph node dissection (LLND) and metastasis are recent hot keywords, and LLND had the highest burst strength. In conclusion, this bibliometric analysis found that Japanese institutions and authors dominated the field of LLNs in rectal cancer. The JCOG0212 trial was the most influential article, which had a significant impact on the development of guidelines. LLND is a hotspot in this field with the highest burst strength. Further prospective studies are needed in this field.

Application of nanotechnology in reversing therapeutic resistance and controlling metastasis of colorectal cancer

Colorectal cancer (CRC) is the most common digestive malignancy across the world. Its first-line treatments applied in the routine clinical setting include surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy. However, resistance to therapy has been identified as the major clinical challenge that fails the treatment method, leading to recurrence and distant metastasis. An increasing number of studies have been attempting to explore the underlying mechanisms of the resistance of CRC cells to different therapies, which can be summarized into two aspects: (1) The intrinsic characters and adapted alterations of CRC cells before and during treatment that regulate the drug metabolism, drug transport, drug target, and the activation of signaling pathways; and (2) the suppressive features of the tumor microenvironment (TME). To combat the issue of therapeutic resistance, effective strategies are warranted with a focus on the restoration of CRC cells’ sensitivity to specific treatments as well as reprogramming impressive TME into stimulatory conditions. To date, nanotechnology seems promising with scope for improvement of drug mobility, treatment efficacy, and reduction of systemic toxicity. The instinctive advantages offered by nanomaterials enable the diversity of loading cargoes to increase drug concentration and targeting specificity, as well as offer a platform for trying the combination of different treatments to eventually prevent tumor recurrence, metastasis, and reversion of therapy resistance. The present review intends to summarize the known mechanisms of CRC resistance to chemotherapy, radiotherapy, immunotherapy, and targeted therapy, as well as the process of metastasis. We have also emphasized the recent application of nanomaterials in combating therapeutic resistance and preventing metastasis either by combining with other treatment approaches or alone. In summary, nanomedicine is an emerging technology with potential for CRC treatment; hence, efforts should be devoted to targeting cancer cells for the restoration of therapeutic sensitivity as well as reprogramming the TME. It is believed that the combined strategy will be beneficial to achieve synergistic outcomes contributing to control and management of CRC in the future.

Recent Progress in Carrier-Free Nanomedicine for Tumor Phototherapy

Safe and effective strategies are urgently needed to fight against the life-threatening diseases of various cancers. However, traditional therapeutic modalities, such as radiotherapy, chemotherapy and surgery, exhibit suboptimal efficacy for malignant tumors owing to the serious side effects, drug resistance and even relapse. Phototherapies, including photodynamic therapy (PDT) and photothermal therapy (PTT), are emerging therapeutic strategies for localized tumor inhibition, which can produce a large amount of reactive oxygen species (ROS) or elevate the temperature to initiate cell death by non-invasive irradiation. In consideration of the poor bioavailability of phototherapy agents (PTAs), lots of drug delivery systems have been developed to enhance the tumor targeted delivery. Nevertheless, the carriers of drug delivery systems inevitably bring biosafety concerns on account of their metabolism, degradation, and accumulation. Of note, carrier-free nanomedicine attracts great attention for clinical translation with synergistic antitumor effect, which is characterized by high drug loading, simplified synthetic method and good biocompatibility. In this review, the latest advances of phototherapy with various carrier-free nanomedicines are summarized, which may provide a new paradigm for the future development of nanomedicine and tumor precision therapy.

Integrated Intensified Chemoradiation in the Setting of Total Neoadjuvant Therapy (TNT) in Patients with Locally Advanced Rectal Cancer: A Retrospective Single-Arm Study on Feasibility and Efficacy

While surgery is considered the main treatment for early-stage rectal cancer, locally advanced rectal cancer needs to be handled with a multidisciplinary approach. Based on literature data suggesting promising advantages of total neoadjuvant therapy (TNT), we performed a retrospective, single-arm, single-center study on 45 patients affected by histologically and radiologically proven locally advanced rectal cancer, with the aim of analyzing the feasibility and short-term efficacy of an integrated intensified treatment in the setting of TNT. Each analyzed patient performed three cycles of FOLFOX4 or De Gramont induction chemotherapy (iCT), followed by concurrent chemoradiotherapy (CRT) with long course radiotherapy (LCRT) plus concomitant boost and continuous 5-FU infusion, followed by three cycles of FOLFOX4 or De Gramont consolidation chemotherapy (conCT) and then surgery with total mesorectal excision. At a median follow-up of 30 months, this strategy has shown to be feasible and effective in terms of pathological complete response (pCR) and short-term disease-free survival (DFS).

Cuprous oxide-based nanocrystals with combined chemo/chemodynamic therapy to increase tumor drug sensitivity by reducing mitochondria-derived adenosine-triphosphate

Gastrointestinal (GI) tumor is a serious disease with high mortality rates and morbidity rates worldwide. Chemotherapy is a key treatment for GI, however, systematic side effects and inevitable drug resistance complicate the situation. In the process of therapy, P-glycoprotein (P-gp) could remove chemotherapy drugs from cells, thus causing multi-drug resistance. Chemodynamic therapy (CDT) utilizing Fenton chemistry has been used for cancer therapy, along with various combination therapies. The reactive oxygen species produced by CDT could inhibit P-gp’s efflux pump function, which reduce chemoagents excretion and reverse drug resistance. In the present study, we developed novel nanocrystals (Cu₂O@Pt NCs) to overcome drug resistance by reducing mitochondria-derived ATP through chemo/CDT in GI cancer. Furthermore, in vivo results in tumor-bearing mice demonstrated that treatment with Cu₂O@Pt NCs with CDT and chemotherapy could achieve the most effective antitumor therapeutic effect with the least amounts of adverse effects. As a result, Cu₂O@Pt NCs could provide a promising strategy for chemo/CDT-synergistic therapy.

Mechanisms of chemotherapeutic resistance and the application of targeted nanoparticles for enhanced chemotherapy in colorectal cancer

Colorectal cancer is considered one of the major malignancies that threaten the lives and health of people around the world. Patients with CRC are prone to post-operative local recurrence or metastasis, and some patients are advanced at the time of diagnosis and have no chance for complete surgical resection. These factors make chemotherapy an indispensable and important tool in treating CRC. However, the complex composition of the tumor microenvironment and the interaction of cellular and interstitial components constitute a tumor tissue with high cell density, dense extracellular matrix, and high osmotic pressure, inevitably preventing chemotherapeutic drugs from entering and acting on tumor cells. As a result, a novel drug carrier system with targeted nanoparticles has been applied to tumor therapy. It can change the physicochemical properties of drugs, facilitate the crossing of drug molecules through physiological and pathological tissue barriers, and increase the local concentration of nanomedicines at lesion sites. In addition to improving drug efficacy, targeted nanoparticles also reduce side effects, enabling safer and more effective disease diagnosis and treatment and improving bioavailability. In this review, we discuss the mechanisms by which infiltrating cells and other stromal components of the tumor microenvironment comprise barriers to chemotherapy in colorectal cancer. The research and application of targeted nanoparticles in CRC treatment are also classified.

Predictive Value of Circulating Tumor Cells Based on Subtraction Enrichment for Recurrence Risk in Stage II Colorectal Cancer

Current guidelines recommend adjuvant chemotherapy (ACT) for stage II colorectal cancer (CRC) patients by using clinical high risk factors, with which circulating tumor cells (CTCs) were not considered. Here, an assessment to detect CTCs based on subtraction enrichment mediated by magnetic beads conjugated with CD45, immunofluorescence staining of CK, and fluorescence in situ hybridization of CEP8 is established. Both CEP8- and CK-positive CTCs have the potential to improve the risk stratification of stage II CRC patients. Patients with preoperative CTCs of ≥4 had a significantly higher recurrence risk than those with preoperative CTCs of <4 in two external validation cohorts (P < 0.0001). In the subgroup with clinical high risk, when preoperative CTCs were <4, patients did not benefit from ACT (P = 0.5764); however, when preoperative CTCs were ≥4, patients received benefit from ACT (P = 0.0064). Additionally, regardless of clinical risk status and preoperative CTC levels, if postoperative CTC levels were ≥4 for more than three consecutive time points (monitoring time interval, 2-6 months), the recurrence rate was 100%. Our findings suggested that the subtraction enrichment of CTCs could provide a reliable method to stratify the recurrence risk and make therapeutic decisions after surgery in stage II CRC patients.

Oxaliplatin-based adjuvant chemotherapy rather than fluorouracil-based chemotherapy in rectal cancer is more efficient to decrease distant metastasis and increase survival after preoperative chemoradiotherapy and surgery: a meta-analysis

PURPOSE

The standard treatment of stage II-III rectal cancer is preoperative chemoradiotherapy (CRT), followed by total mesorectal excision (TME). However, the rate of metastasis is still high following this treatment. Therefore, several adjuvant chemotherapy studies have been conducted on reducing subsequent metastases and increasing survival, although there are still no definite conclusions.

METHODS

We searched for published prospective randomized controlled trials comparing adjuvant chemotherapy regimens following standard preoperative CRT and curative surgery in stage II-III rectal cancer. We systematically searched Medline, Embase, and the Cochrane Library for relevant trials done from January 2004 to January 2021. Review Manager (RevMan, version 5.3) was used to analyze the data.

RESULTS

We initially searched 1955 studies. We screened and carefully selected four randomized controlled trials with 2897 patients. Compared to the 5-FU-based regimen group, the oxaliplatin-added regimen group attained a higher 3-year locoregional control rate (relative risk [RR] of 0.64, 95% confidence interval [CI], 0.48-0.86; p = 0.003) and 3-year distant metastasis control rate (RR of 0.82, 95% CI, 0.71-0.95; p = 0.007). The oxaliplatin-added regimen group had significantly increased 3-year disease-free survival with a hazard ratio (HR) of 0.85 (95% CI: 0.74-0.97, p = 0.020), but not overall survival (p = 0.740). Grade 3 or higher acute toxicity rates did not differ between the two groups (p = 0.190).

CONCLUSION

The addition of oxaliplatin to adjuvant therapy for stage II-III rectal cancer following preoperative CRT and TME may increase disease-free survival without significant increases in toxicity, but not overall survival.

High-dose VitC plus oncolytic adenoviruses enhance immunogenic tumor cell death and reprogram tumor immune microenvironment

Preclinical and clinical studies have validated the antitumor effects of several oncolytic viruses (OVs). However, the efficacy of OVs is limited when they are administered as monotherapies. Combination therapy is a promising direction for oncolytic virotherapy in the future. A high dose of vitamin C (VitC) exerts anticancer effects by triggering the accretion of substantial amounts of reactive oxygen species (ROS). OVs can induce immunogenic tumor cell death and elicit an antitumor immune response. ROS play an important role in immunogenic cell death (ICD). This study aimed to explore whether high-dose VitC in combination with oncolytic adenoviruses (oAds) exhibited a synergistic antitumor effect. High-dose VitC synergized with oAds against tumor by enhancing immunogenic tumor cell death. Combination therapy with high-dose VitC and oAds significantly increased the number of T cells in the tumor microenvironment (TME) and promoted the activation of T cells. Furthermore, the antitumor effect of the combination therapy was CD8⁺ T cell dependent. In addition, combination therapy with high-dose VitC and oAds reprogramed the immunosuppressive TME. Our study provides a new strategy for combination therapy of OVs.

Improving the time to ileostomy closure following an anterior resection for rectal cancer in the UK

AIM

Delayed closure of ileostomy following an anterior resection for rectal cancer in the UK is common. The aims of this study were (i) to investigate the variation in patient pathways between hospitals, (ii) to identify the key learning points from units with the shortest time to closure and (iii) to develop guidance for a pathway to minimize delay in ileostomy closure.

METHOD

This was a mixed methods study. Thirty-eight colorectal units in the UK completed a short online survey. Nine colorectal units in Wales filled in an additional, expanded version of the survey. Semi-structured interviews were performed with clinicians from the six best performing units in terms of timely ileostomy closure. The optimal pathway suggested is based on the best evidence available and the Association of Coloproctology of Great Britain and Ireland guidelines.

RESULTS

Qualitative analysis revealed that 5% of units (n = 2) have a local target time for ileostomy closure. Of all units, 90% (n = 34) would consider implementing a pathway if guidelines were developed. In-depth interviews highlighted the importance of a multidisciplinary approach, a dedicated coordinator to facilitate timely booking, and consensus on whether closure should be performed before or after adjuvant chemotherapy.

CONCLUSION

There is a lack of national guidance in timing of contrast studies and ileostomy closure. Key aspects to consider are better information at consent regarding stoma closure timing, a dedicated person to track patients and the planning of contrast studies at discharge from initial surgery. With a dedicated approach closure of ileostomy within 10-12 weeks is feasible for most units.

Laser activatable nanographene colloids for chemo-photothermal combined gene therapy of triple-negative breast cancer

This investigation reports the green approach for developing laser activatable nanoscale-graphene colloids (nGC-CO-FA) for chemo-photothermal combined gene therapy of triple-negative breast cancer (TNBC). The nano colloid was found to be nanometric as characterized by SEM, AFM, and zeta sizer (68.2 ± 2.1 nm; 13.8 ± 1.2 mV). The doxorubicin (Dox) loaded employing hydrophobic interaction/π-π stacking showed >80% entrapment efficiency with a sustained pH-dependent drug release profile. It can efficiently incorporate siRNA and Dox and successfully co-localize them inside TNBC cells to obtain significant anticancer activity as evaluated using CCK-8 assay, apoptosis assay, cell cycle analysis, cellular uptake, fluorescence assay, endosomal escape study, DNA content analysis, and gene silencing efficacy studies. nGC-CO-FA/Dox/siRNA released the Dox in temperature- and a pH-responsive manner following NIR-808 laser irradiation. The synergistic photo-chemo-gene therapy using near infrared-808 nm laser (NIR-808) irradiation was found to be more effective as compared to without NIR-808 laser-treated counterparts (∆T: 37 ± 1.1 °C → to 49.2 ± 3.1 °C; 10 min; 0.5 W/cm²), suggesting the pivotal role of photothermal combined gene-therapy in the treatment of TNBC.

Heat-inactivated Escherichia coli promotes hematopoietic regeneration after irradiation with IL-1β

BACKGROUND AIMS

Hematopoietic stem and progenitor cells (HSPCs) are known to produce short-lived mature blood cells via proliferation and differentiation in a process that depends partially on regulatory cytokines from the bone marrow (BM) microenvironment. Delayed BM recovery after tremendous damage to the hematopoietic system can lead to neutropenia, anemia, thrombopenia and even death. However, efficiently promote BM recovery is still a big problem to be solved. Here, the authors aim to use heat-inactivated Escherichia coli (HIEC) to enhance BM recovery and further to find out the potential mechanism.

METHODS

X-rad was used to establish HIEC/IL-1β-induced radioprotection model. Single-cell RNA sequencing, RT-PCR, and western blotting were performed to detect the expression of IL-1R1 on HSPCs. Flow cytometry and automated hematology analyzer were used to analyze the percentage and absolute number of different populations of hematopoietic cells. The effects of IL-1β on HSPCs were studied using in vivo and in vitro experiments.

RESULTS

HIEC/IL-1β pre-treatment can significantly increase the survival rate of lethally irradiated mice, and these mice showed better hematopoietic regeneration compared with control group. IL-1R was expressed on HSPCs, and IL-1β could directly function on HSPCs to promote the proliferation and differentiation of HSPCs, and inhibit the apoptosis of HSPCs.

CONCLUSIONS

HIEC pre-treatment can rescue lethally irradiated mice by promoting hematopoietic recovery via IL-1β/IL-1R1 signaling, which can promote the proliferation of HSPCs by enhancing the cell cycle and attenuating the apoptosis of HSPCs.

γ-Ray-Triggered Drug Release of Reactive Oxygen Species-Sensitive Nanomedicine for Enhanced Concurrent Chemoradiation Therapy

Radiotherapy (RT) combined with chemotherapy remains a dominant therapeutic manner in clinical tumor treatment, which is irreplaceable in a short term. To seek an intrinsic connection of combined chemoradiation therapy and maximize the antitumor efficacy, we developed a reactive oxygen species (ROS)-sensitive nanomicelle drug delivery system based on a self-assembled amphiphilic polymer, hyaluronic acid-graft-poly-(propylene sulfide) (HA-PPS). A chemical radiosensitizer, doxorubicin (DOX), was encapsulated into the core of HA-PPS nanomicelles, constituting the DOX-loaded nanomicelles (HA-PPS@DOX NMs) with a spherical structure of around 205.10 ± 11.33 nm diameter with a narrow polydispersity index (PDI) of 0.135 ± 0.01. When combined with RT, the ROS-sensitive HA-PPS@DOX NMs disintegrated and released great drug cargos, which further enhanced cytotoxicity. Meanwhile, as a radiosensitizer, the released DOX sensitized cancer cells to radiotherapy, which has been confirmed by an enhanced sensitizer enhancement ratio (SER) value of 1.78 contributing to the increased cytotoxicity of concurrent chemoradiation tumor therapy, as evidenced by the improvement of half maximal inhibitory concentration (IC₅₀ value) of DOX from 2.316 to 0.8235 μg/mL. Moreover, in vivo studies revealed that HA-PPS@DOX NMs exhibited prolonged circulation time and improved tumor accumulation. Particularly, the released DOX triggered by radiation strengthened radiotherapy sensitization in return. Consequently, these superiorities of HA-PPS@DOX NMs shown by the concurrent chemoradiation tumor therapy resulted in an ideal tumor inhibition rate of 70.4%, thus providing a promising ROS-sensitive nanomedicine for cancer treatment.

Multifunctional nanoplatforms as cascade-responsive drug-delivery carriers for effective synergistic chemo-photodynamic cancer treatment

Synergistic chemo-photodynamic therapy has garnered attention in the field of cancer treatment. Here, a pH cascade-responsive micellar nanoplatform with nucleus-targeted ability, for effective synergistic chemo-photodynamic cancer treatment, was fabricated. In this micellar nanoplatform, 5-(4-carboxyphenyl)-10,15,20-triphenylporphyrin (Por), a photodynamic therapy (PDT) agent was utilized for carrying the novel anticancer drug GNA002 to construct a hydrophobic core, and cyclic RGD peptide (cRGD)-modified polyethylene glycol (PEG) (cRGD-PEG) connected the cell-penetrating peptide hexaarginine (R₆) through a pH-responsive hydrazone bond (cRGD-PEG-N = CH-R₆) to serve as a hydrophilic shell for increasing blood circulation time. After passively accumulating in tumor sites, the self-assembled GNA002-loaded nanoparticles were actively internalized into cancer cells via the cRGD ligands. Once phagocytosed by lysosomes, the acidity-triggered detachment of the cRGD-PEG shell led to the formation of R₆-coated secondary nanoparticles and subsequent R₆-mediated nucleus-targeted drug delivery. Combined with GNA002-induced nucleus-specific chemotherapy, reactive oxygen species produced by Por under 532-nm laser irradiation achieved a potent synergistic chemo-photodynamic cancer treatment. Moreover, our in vitro and in vivo anticancer investigations revealed high cancer-suppression efficacy of this ideal multifunctional nanoplatform, indicating that it could be a promising candidate for synergistic anticancer therapy.

Prognostic Impact of Pretreatment Elevated and Normalized Carcinoembryonic Antigen Levels After Neoadjuvant Chemoradiotherapy in Resected Locally Advanced Rectal Cancer Patients

Purpose

The prognostic significance of pretreatment elevated and normalized CEA after neoadjuvant chemoradiotherapy (nCRT) was evaluated.

Materials and Methods

The characteristics of 951 locally advanced rectal cancer patients with nCRT were retrieved and were analyzed retrospectively. Pretreatment CEA levels were defined as CEA evaluated one week prior to the nCRT. CEA after nCRT was deemed as CEA measured one week before surgery. The normal CEA levels were set at <5 ng/mL. The normal CEA group was defined as patients with normal pretreatment CEA levels. The normalized CEA group was defined as patients with elevated pretreatment CEA levels and normal CEA levels after nCRT. The elevated CEA group was defined as patients with elevated pretreatment CEA levels and elevated CEA levels after nCRT.

Results

Compared with the elevated CEA group, the normalized CEA group was associated with better overall survival (OS) (HR: 0.625, 95%CI: 0.416-0.938, P=0.022). There was no difference between the normalized CEA group and the normal CEA group (HR: 1.143, 95%CI: 0.84-1.557, P=0.395).

Conclusion

In conclusion, the study indicated that OS of the normalized CEA group and the normal CEA group was better than the elevated CEA group.

Application of Field-of-View Optimized and Constrained Undistorted Single Shot (FOCUS) with Intravoxel Incoherent Motion (IVIM) in 3T in Locally Advanced Rectal Cancer

Purpose

To evaluate the efficacy of field-of-view (FOV) optimized and constrained undistorted single shot (FOCUS) with IVIM in 3T MRI in the grading of patients with locally advanced rectal cancer.

Methods

From January 1st to December 31st, 2019, patients with locally advanced rectal cancer were retrieved. FOCUS DWI and FOCUS IVIM were obtained. Apparent diffusion coefficient (ADC) and IVIM parameters including mean true diffusion coefficient (D), pseudodiffusion coefficient associated with blood flow (D∗), and perfusion fraction (f) of the tumor parenchyma and normal rectal wall, as well as the normalized tumor parameters by corresponding normal intestinal wall parameters (ADC_NOR, D_NOR, D∗_NOR, and f_NOR), were compared between the well/moderately differentiated and poorly differentiated groups by Student's t-test. The relationship between the above parameters and the histologic grade was analyzed using Spearman's correlation test, with the ROC curve generated.

Results

Eighty-eight patients (aged 31 to 77 years old, mean = 56) were included for analysis. D_tumor and f_tumor were positively correlated with the tumor grade (r = 0.483, p < 0.001 and r = 0.610, p < 0.001, respectively). All the normalized parameters (ADC_NOR, D_NOR, D∗_NOR, and f_NOR) were positively correlated with the tumor grade (r = 0.267, p = 0.007; r = 0.564, p = 0.001; r = 0.414, p = 0.005; and r = 0.605, p < 0.001, respectively). The best discriminative parameter was the f_tumor value, and the area under the ROC curve was 0.927. With a cut-off value of 22.0%, f_tumor had a sensitivity of 88.9% and a specificity of 100%.

Conclusion

FOCUS IVIM-derived parameters and normalized parameters are useful for predicting the histologic grade in rectal cancer patients.

In vitro evidence of the antitumor capacity of Solanaceae and Cucurbitaceae in colon cancer: A systematic review

Colon cancer is the fourth leading cause of cancer deaths around the world. Despite advances in understanding its etiology and in diagnosis and treatment, new therapeutic strategies are still required. In this sense, the Solanaceae and Cucurbitaceae families have been widely used to treat various pathologies, including cancer, for their bioactive components. The objective of this systematic review was to analyze the antitumor activity of the bioactive components present in extracts from Solanaceae and Cucurbitaceae families using different in in vitro models of colon cancer. 241 publications have been identified (published from January 2008 to January 2020) from different electronic data base. 44 articles were included, 26 of which examined the Solanaceae family. The antitumor activity exhibited by this family was due to the withanolide-type steroid compounds they harbor. 18 articles were related to the Cucurbitaceae family. This family is characterized by their production of cucurbitacin-type triterpenoid compounds and their derivatives, which confer antitumor activity. In conclusion, the different genera belonging to both families are an important source of bioactive compounds with relevant activity against colon cancer. More experimental and in vivo studies will be required to corroborate their antitumor activity and to leverage them in future clinical practice.

Total neoadjuvant therapy for rectal cancer: Making sense of the results from the RAPIDO and PRODIGE 23 trials

A few months ago, results from two randomised phase III trials of total neoadjuvant therapy (TNT) in locally advanced rectal cancer were presented (RAPIDO and PRODIGE 23), consistently showing better short- and long-term outcomes with TNT as compared with standard neoadjuvant long-course chemoradiotherapy (CRT) or short-course radiotherapy (SCRT). These results represent corroborating evidence in support of a practice that many centres had already implemented based on promising preliminary data. Also, they provide new, high-level evidence to endorse TNT as a new management option in the treatment algorithm of stage II-III rectal cancer in those centres where CRT and SCRT have long remained the only accepted standard neoadjuvant treatments. Having two consistently positive trials is certainly reassuring regarding the potential of TNT as a general treatment approach. Nevertheless, substantial differences between these trials pose important challenges in relation to the generalisability and applicability of their results, and translation of the same into practical clinical recommendations. In this article, we address a number of key questions that the RAPIDO and PRODIGE 23 trials have raised among the broad community of gastrointestinal oncologists, proposing an interpretation of the data that may help the decision making, and highlighting grey areas that warrant further investigation.

Pathologic-Based Nomograms for Predicting Overall Survival and Disease-Free Survival Among Patients with Locally Advanced Rectal Cancer

Purpose

Preoperative neoadjuvant therapy is standard before surgery for locally advanced rectal cancer in current clinical treatment. However, patients with the same clinical TNM stage before treatment vary in clinical outcomes. More and more studies noted that pathological findings after preoperative neoadjuvant therapy are better prognostic factors to determine prognosis than clinical TNM stage in patients with locally advanced rectal cancer. The purpose of this study is to develop and validate models based on pathological findings to predict overall survival (OS) and disease-free survival (DFS).

Patients and Methods

A total of 3026 patients from two hospitals were included. The endpoint was OS and DFS. Significant predictors of OS on multivariate analysis were used to establish the nomogram.

Results

The Harrell’s C index for OS prediction was 0.72 (95% confidence interval [CI], 0.68 to 0.77) in the training cohort, 0.66 (95% CI, 0.60 to 0.72) and 0.68 (95% CI, 0.64 to 0.73) in the internal and external validation cohorts. Using this nomogram, high- and low-risk groups for OS were defined in the training cohort. The 3-year OS was 78.1% (95% CI: 72.4–84.2%) for the high-risk group and 95% (95% CI: 93.6–96.5%) in the low-risk group (HR: 4.42, 95% CI: 3.22–6.05; P<0.001). This finding was also applied in the two external cohorts. Similarly, a nomogram that contained the same indices was developed and validated to predict for DFS.

Conclusion

Nomograms based on pathological findings are a reliable tool to predict 3-year OS and DFS rate in patients with locally advanced rectal cancer.

Stratification of Stage III colon cancer may identify a patient group not requiring adjuvant chemotherapy

Purpose

Adjuvant chemotherapy for colon cancer with lymph node involvement (Stage III) has been the standard of care since the 1990s. Meanwhile, considerable evolvement of surgery combined with dedicated histopathological examinations may have led to stage migration. Furthermore, prognostic factors other than lymph node involvement have proven to affect overall survival. Thus, adjuvant chemotherapy in Stage III colon cancer should be reconsidered. The objective was to compare recurrence rates and survival in stage III colon cancer patients treated with or without adjuvant chemotherapy. Further, to assess the impact of extensive mesenterectomy, lymph node stage and vascular invasion on outcome.

Methods

Consecutive patients operated for Stage III colon carcinoma between 31 December 2005 and 31 December 2015 were identified in the pathological code register by matching colon (T67) and either adenocarcinoma (M81403) or mucinous adenocarcinoma (M84803), with lymph node (T08) and metastasis of adenocarcinoma (M81406 or M84806). Medical records of all identified patients were reviewed.

Results

Of 216 identified patients, 69 received no postoperative adjuvant chemotherapy (group NC), 69 insufficient adjuvant chemotherapy (FLV or < minimum recommended 6 cycles FLOX, group IC), and 78 sufficient adjuvant chemotherapy (≥ 6 cycles FLOX, group SC). When adjusted for age and comorbidity, 5-year overall survival did not differ statistically significant between groups (76% vs. 83% vs. 85%, respectively). Vascular invasion and a high lymph node ratio significantly reduced overall survival.

Conclusion

The findings imply that subgroups of Stage III colon cancer patients have good prognosis also without adjuvant chemotherapy. For definite conclusions about necessity of adjuvant chemotherapy, prospective trials are needed.

Long non-coding RNA HOTAIR as a competitive endogenous RNA to sponge miR-206 to promote colorectal cancer progression by activating CCL2

Colorectal cancer (CRC) is one of the common malignant tumors, the incidence of which is on rise. LncHOTAIR, considered as an oncogene, contributed to the progression of a lot of cancers. However, the molecular mechanism and biological functions of the HOTAIR/miR-206/CCL2 axis have not been reported before. Here, our research aimed to explore HOTAIR/miR-206/CCL2 axis in CRC to demonstrate its role in predicting the poor prognosis of CRC. LncHOTAIR, miR-206 and CCL2 mRNA were detected in CRC tissues and cells by RT-PCR. The interactions among LncHOTAIR, miR-206 and CCL2 were explored by luciferase reporter assay, qRT-PCR, western blot and RNA interfere. Flow Cytometry Cell Analysis was performed to detect cell cycle and apoptosis as well as colony assay was prepared to test the cell proliferation. Immunohistochemical analysis was used to detect the CCL2 protein in CRC tissues. In our study, silence of LncHOTAIR by RNA interference could suppress the proliferation, migration and invasion of CRC cells. Mechanistically, LncHOTAIR downregulated miR-206 abundance which indicated that LncHOTAIR was considered as a competing endogenous RNA (ceRNA) by directly sponging miR-206 in CRC cells. In addition, further exploration suggested that miR-206 could inhibit the function of the downstream CCL2, the expression of which was repressed by LncHOTAIR/miR-206 signaling. Furthermore, we verified that the overexpression of CCL2 attenuated CRC cell proliferation, migration, invasion. Overall, this study firstly elucidated that LncHOTAIR played as oncogene in CRC via directly sponging miR-206 to activate the downstream CCL2, which would be considered as the novel therapeutic target in CRC.

Inhibition of miR-19a partially reversed the resistance of colorectal cancer to oxaliplatin via PTEN/PI3K/AKT pathway

Oxaliplatin is a platinum-based chemotherapeutic drug that is effective and commonly used in the treatment of colorectal cancer (CRC). However, long-term use of oxaliplatin usually induces significant drug resistance. It is urgent to develop strategies to reverse the oxaliplatin resistance to CRC cells. In the present study, we established the model of oxaliplatin-resistant CRC cell lines (SW480/R and HT29/R) through continuous treatment of SW480 and HT29 cells with oxaliplatin. Results of qRT-PCR analysis showed that expression of miR-19a was significantly increased in SW480/R and HT29/R compared to their parental SW480 and HT29. However, combination treatment with anti-miR-19a, an antisense oligonucleotide of miR-19a, was found to resensitize SW480/R and HT29/R cells to oxaliplatin treatment. In the mechanism research, we found that anti-miR-19a increased the expression of PTEN and thus inhibited the phosphorylation of PI3K and AKT in SW480/R and HT29/R cells. As a result, mitochondrial apoptosis induced by oxaliplatin was expanded. We demonstrated that PTEN was the target of miR-19a and inhibition of miR-19a partially reversed the resistance of colorectal cancer to oxaliplatin via PTEN/PI3K/AKT pathway.