Capecitabine metronomic chemotherapy inhibits the proliferation of gastric cancer cells through anti-angiogenesis

Capecitabine enhances sensitivity to oxaliplatin in advanced gastric cancer and the effects on patients' FOXP1 and GGT levels

OBJECTIVE

To investigate the effect of capecitabine on the sensitivity of oxaliplatin and on the level of transcription factor forkhead box P1 (FOXP1) and gamma-glutamyl transpeptidase (GGT) in patients with intermediate and advanced gastric cancer.

METHODS

A total of 152 Patients with advanced gastric cancer who were continuously diagnosed and treated in our hospital were selected as the study objects. The general data were retrospectively analyzed. The patients in the control group received oxaliplatin, while the patients in the study group received capecitabine on the basis of the control group. The FOXP1 expression level was detected using immunohistochemistry. Serum levels of GGT were measured by chemiluminescence. Protein levels were detected by Western blot. The prognostic factors were analyzed by the COX regression model. The Kaplan-Meier survival curve was used to analyze the survival of gastric cancer.

RESULTS

The effective rates (complete response, partial response, and stability) of the study group and the control group were 94.74% and 76.32%, respectively. Compared with adjacent normal tissues, the expression level of FOXP1 in gastric cancer tissues was lower (P < 0.05). After treatment, the average expression level of FOXP1 in the gastric cancer tissue of the study group was higher than the control group (P < 0.05). Moreover, lower FOXP1 expression was associated with lower overall survival (OS) (1-year survival and 3-year survival were 75.76% and 53.03%, respectively) (P < 0.05). Further analysis showed that capecitabine combined with oxaliplatin down-regulated the expression of DNA repair related-proteins and up-regulated the expression of key molecules of the apoptosis pathway, thus enhancing the killing effect of oxaliplatin on gastric cancer cells (P < 0.05). Both the 1-year and 3-year survival rates of the study group were higher than that in the control group (P < 0.05). The 1-year survival rate of 152 patients with gastric cancer was 84.87% (129/152) and the 3-year survival rate was 63.17% (96/152). Age, tumor-node-metastasis (TNM) stage, lymph node metastasis, chemotherapy regimen, FOXP1, and GGT levels were important factors in determining OS.

CONCLUSION

Capecitabine effectively enhanced the sensitivity of intermediate and advanced gastric cancer to oxaliplatin, improved the therapeutic effect and ameliorated the prognosis of patients.

Anlotinib plus chemotherapy as a first-line treatment for gastrointestinal cancer patients with unresectable liver metastases: a multicohort, multicenter, exploratory trial

This multicohort phase II trial (ALTER-G-001; NCT05262335) aimed to assess the efficacy of first-line anlotinib plus chemotherapy for gastrointestinal (GI) cancer patients with unresectable liver metastases. Eligible patients with colorectal cancer (Cohort A) or noncolorectal and nonesophageal GI cancer (Cohort C) received six cycles of anlotinib plus standard chemotherapeutic regimens followed by anlotinib plus metronomic capecitabine as a maintenance therapy. Liver metastasectomy can be performed when liver metastases are converted to resectable lesions. The primary outcome was the investigator-confirmed objective response rate (ORR) in the intention-to-treat population. Among the 47 patients in Cohort A, the ORR was 40.4% (95% CI 26.4-55.7), including 1 with a complete response (CR) and 18 who achieved a partial response (PR). The median progression-free survival (PFS) was 8.7 months (95% CI 7.3-NE), and the median overall survival (OS) was not reached. In Cohort C, 14 of 44 patients achieved a PR, with an ORR of 31.8% (95% CI 18.6-47.6). The PFS and OS were 5.8 months (95% CI 4.8-6.5) and 11.4 months (95% CI 5.8-19.3), respectively. The liver metastasectomy rate in patients with liver-limited disease was 22.7% (5/22) in Cohort A and 6.7% (2/30) in Cohort C. For pancreatic cancer patients, the ORR of the efficacy-evaluable population was 36.0% (9/25), and those with liver-limited metastasis had better survival. Moreover, no new safety concerns emerged. In conclusion, an anlotinib-based first-line regimen demonstrated promising antitumor activity among GI cancer patients with unresectable liver metastases and led to liver metastasectomy in selected patients.

Capecitabine enhances sensitivity to oxaliplatin in advanced gastric cancer and the effects on patients' FOXP1 and GGT levels

Objective

To investigate the effect of capecitabine on the sensitivity of oxaliplatin and on the level of transcription factor forkhead box P1 (FOXP1) and gamma-glutamyl transpeptidase (GGT) in patients with intermediate and advanced gastric cancer.

Methods

A total of 152 patients with intermediate and advanced gastric cancer diagnosed and treated in our hospital from April 2018 to May 2019 was selected as the research objects, and their clinical data were retrospectively analyzed. According to the different treatment methods, they were divided into the study group and the control group, with 76 cases in each group. The patients in the control group received with oxaliplatin, while the patients in the study group received with capecitabine on the basis of the control group. The therapeutic effect was evaluated according to the therapeutic effect evaluation criteria of solid tumors. The FOXP1 expression level in gastric cancer tissues was detected using immunohistochemistry. Serum levels of GGT were measured by chemiluminescence. The prognostic factors were analyzed by COX regression model, and the Kaplan-Meier survival curve was used to analyze the relationship between the influencing factors and the survival of gastric cancer.

Results

The effective rate of capecitabine combined with oxaliplatin and oxaliplatin alone in the treatment of patients with intermediate and advanced gastric cancer were 94.74 % and 76.32 % respectively. Capecitabine enhanced the sensitivity of intermediate and advanced gastric cancer to oxaliplatin (P < 0.05). Compared with adjacent normal tissues, the expression level of FOXP1 in gastric cancer tissues was lower (P < 0.05). Before treatment, the expression of FOXP1 was low, and no significant difference was observed in the GGT level between the two groups (P > 0.05). After treatment, the low expression rate of FOXP1 and serum GGT level were both significantly decreased, and those in the study group were lower than those in the control group (P < 0.05). There was no difference in the incidence of adverse reactions between the two groups (P > 0.05). The 1-year survival rates of the study group and the control group were 90.79 % and 78.95 %, while the 3-year survival rates of the study group and the control group were 75.00 % and 51.32 %, respectively. Both the 1-year and 3-year survival rate of the study group was higher than that in the control group (P < 0.05). The 1-year survival rate of 152 patients with gastric cancer was 84.87 % (129/152) and the 3-year survival rate was 63.17 % (96/152). Age, tumor diameter, tumor-node-metastasis (TNM) stage, lymph node metastasis, chemotherapy regimen and the expression of FOXP1 and GGT had significant effects on the survival rate (P < 0.05). Gastric cancer patients with age <60 years, TNM stage of Ⅰ ∼ Ⅱ, lymph node metastasis N0 ∼ N1, high expression of FOXP1, GGT <387.2, and combined with drug chemotherapy had higher survival rate.

Conclusion

Capecitabine effectively enhanced the sensitivity of intermediate and advanced gastric cancer to oxaliplatin, improved the therapeutic effect, reduced the proportion of patients with low FOXP1 expression rate and serum GGT level, decreased the recurrence rate and ameliorated the prognosis of patients.

Effect of immune-modulating metronomic capecitabine as an adjuvant therapy in locoregionally advanced nasopharyngeal carcinoma

INTRODUCTION

Metronomic capecitabine used as an adjuvant therapy improves survival in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). This therapeutic approach may also contribute to improving immune function, consequently enhancing overall therapeutic efficacy.

AIM

We aimed to evaluate the effect of metronomic capecitabine as adjuvant therapy on immune function and survival in cases of LA-NPC.

SUBJECTS AND METHODS

28 patients with LA-NPC were enrolled in the study and equally assigned to two groups of 14 each: experimental and control group. The experimental group received induction chemotherapy + concurrent chemotherapy + adjuvant chemotherapy as well as oral capecitabine at a dose of 650 mg/m² of body surface area twice daily for 1 year, with the option to discontinue in case of intolerance. The control group did not receive additional chemotherapy or targeted drugs after the induction chemotherapy + concurrent chemoradiotherapy; however, they were followed up regularly. Changes in immune function and survival were compared between the two groups.

RESULTS

The median follow-up time was 43.5 months. One year after adjuvant chemotherapy, the experimental group showed higher levels of CD8 + cells, CD28 + CD8 + cells, and activated CD8 + cells compared to the control group (P < 0.05). The CD4/CD8 ratio and proportion of monocyte-derived dendritic cells were also higher in the experimental group than in the control group, but the difference was not statistically significant (P ≥ 0.05). Comparisons of 3-year overall survival, local-regional recurrence-free survival, progression-free survival, and distant metastasis-free survival between the two groups showed percentages of 92.9% vs. 78.6%, 92.9% vs. 92.9%, 78.6% vs. 71.4%, and 85.7% vs. 0.78 0.6% respectively, but these differences were not significant (P > 0 0.05 ).

CONCLUSION

Metronomic capecitabine chemotherapy was observed to induce an immunomodulatory effect in LA-NPC.

TRIAL REGISTRATION

NCT02958111, date of registration 04-11-2016.

Chemo-immune cell therapy by intratumoral injection of adoptive NK cells with capecitabine in gastric cancer xenograft model

Introduction

Gastric cancer is one of the most commonly known malignancies and is the fifth cancer-related death globally. Whereas natural killer (NK) cells play a critical role in tumor elimination; therefore, adoptive NK cell therapy has become a promising approach in cancer cytotherapy. Hence, this study investigated the chemo-immune cell therapy in MKN-45 derived xenograft gastric cancer model.

Methods

Three groups of animals have received the following treatments separately: activated NK cells, capecitabine, the combination of capecitabine and activated NK cells, and one was considered as the control group. Morphometric properties of tumor samples were evaluated at the end of the study. NK cells infiltration was evaluated by immunohistochemistry (IHC) of hCD56. Mitotic count and treatment response was assessed by hematoxylin and eosin (H&E) staining. The proliferation ratio to apoptosis was determined by IHC assessment of Ki67 and caspase 3.

Results

The results indicated that the NK cell therapy could effectively decrease the mitotic count in pathology assessment, but the tumor was not completely eradicated. In combination with metronomic chemotherapy (MC) of capecitabine, NK cell therapy demonstrated a significant difference in tumor morphometric properties compared to the control group. The proliferation ratio to apoptosis was also in line with pathology data.

Conclusion

Although NK cell therapy could effectively decrease the mitotic count in vivo, the obtained findings indicated lesser potency than MC despite ex vivo activation. In order to enhance NK cell therapy effectiveness, suppressive features of the tumor microenvironment and inhibitory immune checkpoints blockade should be considered.

Metronomic Chemotherapy for Metastatic Breast Cancer

BACKGROUND

As disease control and quality of life play a leading role in metastatic breast cancer (MBC), metronomic chemotherapy (MCT) is gaining popularity alongside conventional chemotherapy (CCT) and targeted therapies.

SUMMARY

MCT, defined as continuous administration of low-dose chemotherapeutic agents, is accepted as a therapy that exerts its effects via immunomodulation, anti-angiogenesis and direct cytotoxic effects. Oral administration of MCT is safe, easy to handle, and allows for flexible drug dosing. Dose accumulations associated with non-tolerable side effects are rare, so the medication can be administered for longer periods of time. Patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic disease resistant to endocrine-based therapy and not requiring rapid tumor response are generally suitable for MCT. However, MCT may also be promising in patients with triple-negative and HER2-positive tumors without aggressive disease who prefer a lower toxicity profile compared to CCT. The most commonly used agents are cyclophosphamide (CTX), methotrexate (MTX), capecitabine (CAPE), and vinorelbine (VRL), whereby a combination of agents is frequently applied. Key Messages: Based on the growing body of evidence, MCT can be considered as a suitable treatment option in selected MBC patients. Nevertheless, there is an urgent need for randomized controlled trials comparing MCT with CCT, but also with best supportive care. Due to the multimodal mechanisms of action, the combination with targeted and immunological therapies may represent a new promising approach for the treatment of MBC.

Prognostic Value of EGFR Expression for Patients With Stage III Colorectal Cancer Receiving Fluoropyrimidine Metronomic Maintenance Therapy After Radical Resection and Adjuvant Oxaliplatin-Based Chemotherapy

This study evaluated the survival effects of metronomic maintenance therapy with oral fluoropyrimidine in patients with stage III colorectal cancer (CRC) according to epidermal growth factor receptor (EGFR) expression. We enrolled 197 patients with stage III CRC who had undergone radical resection and FOLFOX regimen adjuvant chemotherapy. The clinicopathological features and effects of metronomic maintenance therapy with oral capecitabine (daily dose of 850 mg/m², twice daily, on days 114 every 3 weeks for 6 months) on survival according to treatment group and EGFR expression were analyzed. By conducting an in vitro cell line study and in vivo study through knockout of the EGFR gene, we analyzed the capacities of cell proliferation and migration. Relapse and survival were significantly more common in the FOLFOX group. Metronomic maintenance therapy was a significantly independent associated factor of relapse and survival as well as a prognostic factor of disease-free survival and overall survival. Significant intergroup differences in survival were only observed in patients with positive EGFR expression. Thus, our findings suggest EGFR expression is a prognostic factor in patients with stage III CRC receiving metronomic maintenance therapy. Analysis of EGFR expression in these patients helps identify potential candidates who may receive the optimal survival benefit from metronomic maintenance therapy.

Biomarker-targeted therapies for advanced-stage gastric and gastro-oesophageal junction cancers: an emerging paradigm

Advances in cancer biology and sequencing technology have enabled the selection of targeted and more effective treatments for individual patients with various types of solid tumour. However, only three molecular biomarkers have thus far been demonstrated to predict a response to targeted therapies in patients with gastric and/or gastro-oesophageal junction (G/GEJ) cancers: HER2 positivity for trastuzumab and trastuzumab deruxtecan, and microsatellite instability (MSI) status and PD-L1 expression for pembrolizumab. Despite this lack of clinically relevant biomarkers, distinct molecular subtypes of G/GEJ cancers have been identified and have informed the development of novel agents, including receptor tyrosine kinase inhibitors and monoclonal antibodies, several of which are currently being tested in ongoing trials. Many of these trials include biomarker stratification, and some include analysis of circulating tumour DNA (ctDNA), which both enables the noninvasive assessment of biomarker expression and provides an indication of the contributions of intratumoural heterogeneity to response and resistance. The results of these studies might help to optimize the selection of patients to receive targeted therapies, thus facilitating precision medicine approaches for patients with G/GEJ cancers. In this Review, we describe the current evidence supporting the use of targeted therapies in patients with G/GEJ cancers and provide guidance on future research directions.

Prognosis prediction model for a special entity of gastric cancer, linitis plastica

Background

Gastric linitis plastica (GLP) is characteristic by its poor prognosis and highly aggressive characteristics compared with other types of gastric cancer (GC). However, the guidelines have not yet been distinguished between GLP and non-GLP.

Methods

A total of 342 eligible patients with GLP identified in the Surveillance, Epidemiology, and End Results (SEER) dataset were randomly divided into training set (n=298) and validation set (n=153). A nomogram would be developed with the constructed predicting model based on the training cohort's data, and the validation cohort would be used to validate the model. Principal component analysis (PCA) was used to evaluate the differences between groups. Cox regression and LASSO (least absolute shrinkage and selection operator) were used to construct the models. Calibration curve, time-dependent receiver operating characteristic (ROC) curve, concordance index (C-index) and decision curve analysis (DCA) were used to evaluate the predicting performance. Restricted mean survival time (RMST) was used to analyze the curative effect of adjuvant therapy.

Results

For patients in training cohort, univariable and multivariable Cox analyses showed that age, examined lymph nodes (LN.E), positive lymph nodes (LN.P), lesion size, combined resection, and radiotherapy are independent prognostic factors for overall survival (OS), while chemotherapy can not meet the proportional hazards (PHs) assumption; age, race, lesion size, LN.E, LN.P, combined resection and marital status are independent prognostic factors for cancer-specific survival (CSS). The C-index of the nomogram was 0.678 [95% confidence interval (CI), 0.660-0.696] and 0.673 (95% CI, 0.630-0.716) in the training and validation cohort, respectively. Meanwhile, the C-index of the CSS nomogram was 0.671 (95% CI, 0.653-0.699) and 0.650 (95% CI, 0.601-0.691) in the training and validation cohort for CSS, respectively. Furthermore, the nomogram was well calibrated with satisfactory consistency. RMST analysis further determined that chemotherapy and radiotherapy might be beneficial for improving 1- and 3-year OS and CSS, but not the 5-year CSS.

Conclusions

We developed nomograms to help predict individualized prognosis for GLP patients. The new model might help guide treatment strategies for patients with GLP.

Treatment Strategies of Gastric Cancer-Molecular Targets for Anti-angiogenic Therapy: a State-of-the-art Review

Purpose

Recent studies have suggested that molecular targets for the anti-angiogenic therapy might constitute a basis for additional therapy in gastric cancer treatment. A vast number of molecules, receptors, pathways, specific interactions, and thus strategies that target gastric cancer angiogenesis specifically have been reported in numerous research articles and clinical trials.

Methods

We conducted a systematic literature review of molecularly targeted treatment strategies in gastric cancer on the following databases—PubMed, Google Scholar, and Scopus—on September 20, 2020. Multiple articles and evaluations were searched for studies reporting newly found and promising molecular anti-angiogenic therapy pathways. Eventually, 39 articles regarding the anti-angiogenic therapy in gastric cancer were included in the final analysis.

Results

As a consequence of the release of the pro-angiogenic molecules from the tumour cells, gastric cancer presents high angiogenic capability. Therefore, potential schemes for future treatment strategies include the decrease of the process ligands as well as the expression of their receptors. Moreover, the increase in the angiogenic inhibitor levels and direct aim for the inner walls of the endothelial cells appear as a promising therapeutic strategy. Beyond that, angiogenesis process inhibition seems to indirectly exaggerate the effects of chemotherapy in the considered patients.

Conclusions

The anti-angiogenic treatment in gastric cancer patients evaluates its significance especially in the early stages of the malignancy. The studies conducted so far show that most of the meaningful angiogenic factors and receptors with the potential molecular pathways should be further evaluated since they could potentially play a substantial role in future therapies.

Early changes in intravoxel incoherent motion MRI parameters can potentially predict response to chemoradiotherapy in rectal cancer: An animal study

Imaging-based approaches for early predicting response of rectal cancer to neoadjuvant chemoradiotherapy remain an ongoing-challenge. In this study, we aimed to monitor the changes of intravoxel incoherent motion (IVIM) MRI parameters during the early post-treatment period in mouse models of human rectal carcinoma, and to test whether these changes relate to the final response. Thirty-two mice with subcutaneous-tumor were randomly divided into control (n = 11), chemoradiotherapy (n = 10) and chemotherapy (n = 11) group. Tumors were monitored by IVIM at day 0, 3, 7, 9 after treatment. The final tumor response was determined by tumor remission-rate and necrosis scores. The results indicated that within 9 days after treatment, D values increased in both treated groups, but remained stable in control group. D values were significantly higher in chemotherapy group at day 7 and in each treated group at day 9 than in control group (day 7, p = 0.004; day 9: p = 0.011 and 0.009, respectively). D* values decreased in treated groups, and showed significantly lower than in control group at day 7 (p < 0.001). There was a strong positive correlation between delta D*% (D*_{day0 - day7}/D*_day0) and tumor remission rate (r = 0.707, p < 0.001), and a mild negative correlation between delta D% and tumor necrosis scores (r = -0.526, p = 0.014). D and D* values in rectal carcinoma xenograft models appeared tendency change during the early post-treatment period. In conclusion, early changes of D and D* values may have potential for predicting the final efficacy of chemoradiotherapy.

MOMENTUM: A Phase I Trial Investigating 2 Schedules of Capecitabine With Aflibercept in Patients With Gastrointestinal and Breast Cancer

BACKGROUND

Although data from preclinical and clinical studies provide a strong rationale for combining capecitabine with anti-angiogenic agents, clinical development of this fluoropyrimidine in combination with aflibercept has lagged behind other treatments. We conducted a nonrandomized, noncomparative, 2-arm, phase I trial to address this unmet need.

PATIENTS AND METHODS

Patients with chemorefractory gastrointestinal and breast cancer were sequentially recruited into a continuous (Arm A, starting dose 1100 mg/m²/day) or intermittent (Arm B, 2 weeks on/1 week off, starting dose 1700 mg/m²/day) capecitabine dosing arm. Aflibercept was administered at a flat dose of 6 mg/kg every 3 weeks in both arms. A classical 3 + 3, dose-escalation design was used. The primary objective was to establish the maximum tolerated dose, dose-limiting toxicities (DLTs), and recommended dose for phase II trials.

RESULTS

Thirty-eight eligible patients were recruited of whom 33 were assessable for DLTs (15 in arm A and 18 in arm B). Fourteen had colorectal cancer, 8 gastric cancer, and 11 breast cancer. DLTs included grade 2 hand-foot syndrome, grade 2 anorexia considered unacceptable by the patient, and grade 3 hypertension. The recommended dose for phase II trials for capecitabine was established at 1300 mg/m²/day in Arm A and 2500 mg/m²/day in Arm B with treatment-related grade ≥ 3 adverse events occurring in 47% and 50% of patients, respectively. Among 26 assessable patients, the objective response rate was 15.4% in Arm A and 7.7% in Arm B.

CONCLUSION

Combining capecitabine with aflibercept is feasible and associated with a manageable safety profile and some anti-tumor activity in patients with chemorefractory gastrointestinal and breast cancer.

Anti-Angiogenic Effect of Orally Available Pemetrexed for Metronomic Chemotherapy

Metronomic chemotherapy (MCT) is defined as the frequent administration of low-dose chemotherapeutics, without long drug-free periods, with the exertion of antitumor activity exclusively through anti-angiogenic mechanisms. In this study, we have developed an orally available formulation of pemetrexed (PMX) for MCT. PMX was first complexed ionically with N^α-deoxycholyl-l-lysyl-methylester (DCK) as the permeation enhancer. This was followed by dispersion with poloxamer 188 and Labrasol to form the solid oral formulation of PMX (PMX/DCK-OP). PMX/DCK-OP exhibited a 10.6-fold increase in permeability across a Caco-2 cell monolayer compared to PMX alone. This resulted in a 70-fold increase in the oral bioavailability of PMX/DCK-OP in mice over oral PMX alone. In the A549 xenograft model, tumor volume was reduced by 51.1% in the PMX/DCK-OP treated group compared to only 32.8% in the maximum tolerated dose (MTD)-treated group. Furthermore, PMX/DCK-OP exhibited a significant anti-angiogenic effect on the A549 xenograft mice when compared to the MTD-treated group, as indicated by microvessel density quantification for CD-31. In addition, PMX/DCK-OP enhanced the release of an endogenous angiogenesis inhibitor, thrombospondin-1 (TSP-1), into both the blood circulation and the tumor microenvironment. Therefore, due to its oral route of administration, PMX/DCK-OP appears to be a better alternative to the conventional treatment of PMX.

Tumor endothelial cells as a potential target of metronomic chemotherapy

Drug resistance and toxic side effects are major therapeutic hurdles affecting cancer patients receiving conventional chemotherapy based on the maximum tolerated dose. Metronomic chemotherapy (MCT), a new therapeutic approach developed to avoid these problems generally, consists of the continuous administration of low-dose cytotoxic agents without extended intervals. This therapy targets the tumor microenvironment, rather than exerting a direct effect on tumor cells. As a result, the MCT regimen functionally impairs tumor endothelial cells and circulating endothelial progenitor cells, leading to tumor dormancy via anti-angiogenesis. Over the past 10 years, several studies have highlighted the impact of MCT on the tumor microenvironment and angiogenesis and demonstrated its potential as a switch from the pro-angiogenic to the anti-angiogenic state. However, the mechanisms of action are still obscure. Here, we systematically review the evidence regarding the anti-angiogenic potential of MCT as a crucial determinant of tumor dormancy and cancer treatment.

Rationale for the use of metronomic chemotherapy in gastrointestinal cancer

INTRODUCTION

Metronomic chemotherapy (mCT) is endowed with various properties, ranging from antiangiogenic to immunomodulation, and may revert tumor resistance to conventional drug administration. A variety of antineoplastic agents displayed activity when administered with metronomic schedules in preclinical models of gastrointestinal cancers. However, most of the field is still unexplored.

AREAS COVERED

Herein, the authors review the existing literature from PubMed, concerning the use of mCT in gastrointestinal oncology.

EXPERT OPINION

A mounting body of evidence is emerging in support of mCT as a treatment option for gastrointestinal tumors, but the frequent signs of clinical activity inconsistently translate into a benefit for survival. Research in this field should focus on providing high-quality evidence on the safety and efficacy of mCT, with more prospective, comparative trials; identifying the subgroups of patients for whom mCT would be the best approach; establishing standardized protocols based on mCT pharmacokinetics and pharmacodynamics; developing drug activity biomarkers. mCT is also potentially suitable for combinations with targeted antiangiogenic drugs and may be incorporated with conventional administration into dual regimens.

Does metronomic chemotherapy induce tumor angiogenic dormancy? A review of available preclinical and clinical data

Tumor dormancy is the ability of cancer cells to survive in a non-proliferating state. This condition can depend on three main mechanisms: cell cycle arrest (quiescence or cell dormancy), immunosurveillance (immunologic dormancy), or lack of functional blood vessels (angiogenic dormancy). In particular, under angiogenic dormancy, cancer cell proliferation is counterbalanced by apoptosis owing to poor vascularization, impeding tumor mass expansion beyond a microscopic size, with an asymptomatic and non-metastatic state. Tumor vasculogenic or non-angiogenic switch is essential to promote escape from tumor dormancy, leading to tumor mass proliferation and metastasis. In avascular lesions angiogenesis process results blocked from the equilibrium between pro- and anti-angiogenic factors, such as vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1), respectively. The angiogenic switch mainly depends on the disruption of this balance, in favor of pro-angiogenic factors, and on the recruitment of circulating endothelial progenitors (CEPs) that promote the formation of new blood vessels. Metronomic chemotherapy, the regular intake of doses able to sustain low but active concentrations of chemotherapeutic drugs during protracted time periods, is an encouraging therapeutic approach that has shown to upregulate anti-angiogenic factors such as TSP-1 and decline pro-angiogenic factors such as VEGF, suppressing the proangiogenic cells such as CEPs. In this perspective, metronomic chemotherapy may be one of the available therapeutic approaches capable to modulate favorably the angiogenic tumor dormancy, but further research is essential to better define this particular characteristic.

Metronomic chemotherapy remodel cancer-associated fibroblasts to decrease chemoresistance of gastric cancer in nude mice

The present study aimed to evaluate whether capecitabine or 5-fluorouracil (5-Fu) chemotherapy with the metronomic pattern may cause significant chemoresistance compared with the traditional pattern, and whether CAFs are involved in drug resistance. SGC-7901 cells were subcutaneously injected into the nude mice, and the mice were divided into five groups: The control group, intraperitoneally injected with normal saline; the 5-Fu conventional dose group [5-Fu maximum tolerated dose (MTD) group], intraperitoneally injected with 50 mg/kg, twice per week for 2 weeks, with an 1-week discontinuation for 6 weeks; the capecitabine conventional dose group (capecitabine MTD group), intragastric 500 mg/kg, twice per week for 2 weeks, with a 1-week discontinuation for 6 weeks; the 5-Fu metronomic group [5-Fu low-dose metronomic (LDM) group], intraperitoneally injected with 15 mg/kg, twice a week for 6 weeks; and the capecitabine metronomic group (capecitabine LDM group), intragastric administration at 200 mg/kg, twice a week for 6 weeks. The chemotherapy resistance markers [glutathione transferase Pi (GSTP) and multidrug resistance protein 1 (MDR1)] were detected by immunohistochemical staining (IHC), and the association of the expression of these markers with the chemotherapy administration patterns was analyzed. Vascular endothelial growth factor (VEGF) and the cancer-associated fibroblast (CAF) marker α-smooth muscle actin were also examined by IHC to illustrate the possible mechanism of chemoresistance. The expression of GSTP and MDR1 in the MTD groups was significantly higher compared with those of the LDM groups (P<0.01). Furthermore, the number of CAFs and the level of VEGF in the MTD groups were significantly higher compared with those of the LDM groups (P<0.05). The low dose metronomic chemotherapy did not increase the risk of chemoresistance compared with the conventional dose traditional chemotherapy in terms of capecitabine or 5-Fu, the increasing amount of CAFs in the microenvironment of cancer cell following therapy may protect cell from capecitabine or 5-Fu via producing VEGF to increase vascularization.

Potential role of metronomic chemotherapy in the treatment of esophageal and gastroesophageal cancer

Patients with esophagogastric cancer have poor prognoses in spite of the best available therapies. Patients are debilitated and may not tolerate, or may progress, on standard cytotoxic chemotherapy regimens. Metronomic chemotherapy is an attractive treatment option due to its very low reported toxicity, modest efficacy, low cost and ease of administration. Capecitabine is the most common drug used in metronomic scheduling; other drugs include cyclophosphamide and paclitaxel. Dosing of capecitabine can range from 1000 mg orally daily for 4 weeks on and 1 week off to a continuous dosing schedule of 1500 mg orally daily. Reported toxicities, including neutropenia, mucositis and hand-foot syndrome, occur in <10% of patients. As there is a lack of well-conducted, randomized clinical trials evaluating the role of metronomic chemotherapy in esophagogastric cancer, it cannot be recommended as the standard of care; however, it can be considered to be a therapeutic option, especially in elderly patients with relapsed disease for whom other therapeutic options are limited.

Keloid and Hypertrophic Scars Are the Result of Chronic Inflammation in the Reticular Dermis

Keloids and hypertrophic scars are caused by cutaneous injury and irritation, including trauma, insect bite, burn, surgery, vaccination, skin piercing, acne, folliculitis, chicken pox, and herpes zoster infection. Notably, superficial injuries that do not reach the reticular dermis never cause keloidal and hypertrophic scarring. This suggests that these pathological scars are due to injury to this skin layer and the subsequent aberrant wound healing therein. The latter is characterized by continuous and histologically localized inflammation. As a result, the reticular layer of keloids and hypertrophic scars contains inflammatory cells, increased numbers of fibroblasts, newly formed blood vessels, and collagen deposits. Moreover, proinflammatory factors, such as interleukin (IL)-1α, IL-1β, IL-6, and tumor necrosis factor-α are upregulated in keloid tissues, which suggests that, in patients with keloids, proinflammatory genes in the skin are sensitive to trauma. This may promote chronic inflammation, which in turn may cause the invasive growth of keloids. In addition, the upregulation of proinflammatory factors in pathological scars suggests that, rather than being skin tumors, keloids and hypertrophic scars are inflammatory disorders of skin, specifically inflammatory disorders of the reticular dermis. Various external and internal post-wounding stimuli may promote reticular inflammation. The nature of these stimuli most likely shapes the characteristics, quantity, and course of keloids and hypertrophic scars. Specifically, it is likely that the intensity, frequency, and duration of these stimuli determine how quickly the scars appear, the direction and speed of growth, and the intensity of symptoms. These proinflammatory stimuli include a variety of local, systemic, and genetic factors. These observations together suggest that the clinical differences between keloids and hypertrophic scars merely reflect differences in the intensity, frequency, and duration of the inflammation of the reticular dermis. At present, physicians cannot (or at least find it very difficult to) control systemic and genetic risk factors of keloids and hypertrophic scars. However, they can use a number of treatment modalities that all, interestingly, act by reducing inflammation. They include corticosteroid injection/tape/ointment, radiotherapy, cryotherapy, compression therapy, stabilization therapy, 5-fluorouracil (5-FU) therapy, and surgical methods that reduce skin tension.

Vascular Endothelial Growth Factor and Cluster of Differentiation 34 for Assessment of Perioperative Bleeding Risk in Gastric Cancer Patients

Background:

Angiogenesis is the formation of new blood vessels to supply nutrients to tumors. Vascular endothelial growth factor (VEGF) and cluster of differentiation 34 (CD34) are important signaling proteins involved in angiogenesis. Many studies have demonstrated that VEGF and CD34 are related to tumor progression. This study focused on the relationship between VEGF, CD34, and perioperative hemorrhage in patients with gastric cancer.

Methods:

To observe the relationship between VEGF and CD34, we tracked 112 patients with advanced gastric cancer for 5 years to assess factors related to hemorrhage, using immunohistochemistry. The results were subjected to statistical analysis using a 2 × 2 contingency table, logistic regression, and receiver operating characteristic (ROC) test.

Results:

The concentrations of VEGF and CD34 were critically correlated with perioperative hemorrhage and neural invasion in patients with gastric cancer (P < 0.05). Expression of VEGF and CD34 was related (P < 0.05, χ² = 6.834). VEGF and CD34 co-expression strongly increased the risk of preoperative bleeding (area under the ROC curve >0.7, P < 0.05).

Conclusions:

Expression of VEGF and CD34 was critically correlated with perioperative hemorrhage in gastric cancer patients. Co-expression of VEGF and CD34 could be an effective indicator for evaluating the risk of perioperative bleeding in gastric cancer patients.

The telomere-binding protein TRF2 is required for metronomic therapeutic effects of gemcitabine and capecitabine

Gemcitabine and capecitabine are two effective anticancer agents against solid tumors. The pharmacological mechanisms have been known as incorporation into DNA and thereby inhibition of DNA synthesis. When used as metronomic chemotherapy, they may inhibit angiogenesis and induce immunity. In our previous study, we showed that low-dose gemcitabine caused telomere shortening by stabilizing TRF2 that was required for XPF-dependent telomere loss. In this report, we established a SKOV3.ip1 ascites cell model. Tumor-bearing mice were treated with low-dose gemcitabine (GEM) or capecitabine (CAP). Both GEM and CAP caused telomere shortening and increased expression of TRF2 with improved ascites in nude mice and decreased in vitro clonogenic activity. TRF2 knockdown altered telomeres to a shortened but new status that may evade XPF-dependent telomere loss and conferred resistance of SKOV3.ip1 ascites cells to low-dose GEM and CAP. Our study provides a new mechanism of metronomic chemotherapy i.e. TRF2 is required for metronomic therapeutic effects of gemcitabine and capecitabine.

Continuous administration of bevacizumab plus capecitabine, even after acquired resistance to bevacizumab, restored anti-angiogenic and antitumor effect in a human colorectal cancer xenograft model

Vascular endothelial growth factor (VEGF)-neutralizing therapy with bevacizumab has become increasingly important for treating colorectal cancer. It was demonstrated that second-line chemotherapy together with bevacizumab after disease progression (PD) on first-line therapy including bevacizumab showed clinical benefits in metastatic colorectal and breast cancers (ML18147 trial, TANIA trial). One of the rationales for these trials was that the refractoriness to first-line therapy is caused by resistance to not so much bevacizumab as to the chemotherapeutic agents. Nevertheless, resistance to bevacizumab cannot be ruled out because VEGF-independent angiogenesis has been reported to be a mechanism of resistance to anti-VEGF therapy. In this study, we used a xenograft model with the human colon cancer HT-29 cells to investigate the mechanisms underlying the effect of continued administration of bevacizumab plus capecitabine even after resistance to bevacizumab was acquired. The combination of capecitabine plus bevacizumab exhibited significantly stronger antitumor and anti-angiogenic activities than did monotherapy with either agent. Capecitabine treatment significantly increased the intratumoral VEGF level compared with the control group; however, the combination with bevacizumab neutralized the VEGF. Among angiogenic factors other than VEGF, intratumoral galectin-3, which reportedly promotes angiogenesis both dependent on, and independently of VEGF, was significantly decreased in the capecitabine group and the combination group compared with the control group. In an in vitro experiment, 5-fluorouracil (5-FU), an active metabolite of capecitabine, inhibited galectin-3 production by HT-29 cells. These results suggested that capecitabine has a dual mode of action: namely, inhibition of tumor cell growth and inhibition of galectin-3 production by tumor cells. Thus, capecitabine and bevacizumab may work in a mutually complementary manner in tumor angiogenesis inhibition to overcome the resistance caused by angiogenic factors other than VEGF. These results suggest the clinical relevance and the mechanism of action of treatment with bevacizumab in combination therapy beyond PD.