Less is more, regularly: metronomic dosing of cytotoxic drugs can target tumor angiogenesis in mice

Adjuvant Metronomic Chemotherapy After Surgery in pT1-T2 N0 M0 HER2-Positive and ER/PR-Positive Breast Cancer Plus Targeted Therapy, Anti-Hormonal Therapy, and Radiotherapy, with or Without Immunotherapy: A New Operational Proposal

Breast cancer is the most common and deadly female-specific malignancy in the world. Four immunohistochemical subtypes are distinguished: luminal A, luminal B, HER2-positive, and triple-negative. In turn, the HER2-positive subtype presents two variants depending on the status of the hormone receptors. The variant that expresses them can benefit from both anti-HER2 and anti-hormonal therapy. Today, MCTP finds application in maintenance therapy after standard of care and in advanced breast cancer when the patient's clinical condition is already seriously compromised by metastatic disease; in this context, it is used as a first-line treatment, in pre-treated subjects, or as a rescue treatment. Here, the use of adjuvant oral MCTP after surgery at an early stage in HER-2 and hormone-positive local breast cancer is proposed, where effective treatment options are available, such as anti-HER2 therapy (e.g., trastuzumab, pertuzumab), anti-hormonal therapy (e.g., tamoxifen, letrozole), radiotherapy, and, in case of strong PD-1 positivity, immunotherapy.

Metronomic Capecitabine Plus Aromatase Inhibitor as Initial Therapy in Patients With Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer: The Phase III MECCA Trial

PURPOSE

The effects of metronomic chemotherapy plus endocrine therapy have yet to be elucidated through a randomized phase III clinical trial.

METHODS

Randomized clinical trials were conducted at 12 centers in China from August 22, 2017, to September 24, 2021, and the final follow-up date was August 25, 2023. Patients with hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC) who had no previous systemic therapy in the metastatic setting were enrolled. Participants were 1:1 assigned to receive either metronomic capecitabine plus an aromatase inhibitor (AI) or AI alone. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), objective response rate, disease control rate (defined as disease controlled for ≥24 weeks), and safety.

RESULTS

A total of 263 patients were randomly assigned, among which 254 patients formed the full analysis set. At the median follow-up time of 50.7 months, 203 PFS events occurred. The metronomic capecitabine plus AI arm exhibited a median PFS of 20.9 months compared with 11.9 months in the AI arm (hazard ratio [HR], 0.58 [95% CI, 0.43 to 0.76]). The median OS was not reached in the combination arm and was 45.1 months in the AI arm (HR, 0.58 [95% CI, 0.37 to 0.93]). The most common adverse events were palmar-plantar erythrodysesthesia and peripheral neuropathy; grade 3 events occurred in 15.1% of the patients receiving combination treatment.

CONCLUSION

The MECCA trial demonstrated a significant improvement in PFS and OS with first-line metronomic capecitabine plus AI compared with AI alone in patients with hormone receptor-positive+/HER2-negative MBC. Both treatment arms exhibited tolerable safety profiles consistent with previous reports.

Angiogenesis Is Associated With Aggressive Biology That Counterbalances With Tumor Immunogenicity in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is an arterialized tumor; thus, anti-angiogenesis targeted therapy is in clinical practice. Herein, we hypothesized that HCC with high angiogenesis is biologically aggressive with worse survival.

Methods

Angiogenesis score (AS) was derived from the Molecular Signatures Database (MSigDB) Hallmark Angiogenesis Gene Set, and median was used to divide high versus low groups. Transcriptome of HCC patients of The Cancer Genome Atlas (TCGA, n = 386) and GSE76427 (n = 115) cohorts were analyzed.

Results

High AS correlated with angiogenesis-related gene expressions. Both microvascular and lymphatic endothelial cell infiltrations were higher in high angiogenesis HCC. Surprisingly, no survival difference was seen with varying levels of angiogenesis. High angiogenesis significantly enriched tumor aggravating signaling pathways: glycolysis, Notch, Hedgehog, KRAS, epithelial mesenchymal transition, and transforming growth factor-beta (TGF-β) in Gene Set Enrichment Analysis (GSEA), but also infiltrated less CD8+ T cells and T-helper 1 cells, and higher M1 macrophages and conventional dendritic cells (cDCs) with elevated cytolytic activity score in both cohorts. In agreement, immune response-related gene sets: inflammatory response, tumor necrosis factor-alpha (TNF-α) signaling, allograft rejection, interferon-alpha, and interferon-gamma were all enriched to high angiogenesis HCC. Programmed cell death protein 1 (PD1), programmed death ligand 1 (PD-L1), programmed death ligand 2 (PD-L2), and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) were higher in high angiogenesis HCC in TCGA, but not in GSE76427 cohort.

Conclusions

Angiogenesis quantified using transcriptome of HCC patients demonstrated that it is associated with aggressive biology but also with tumor immunogenicity and immune response that counterbalance and did not reflect in survival. Given high expression of immune checkpoint molecules, we cannot help but speculate that immunotherapy may be useful for high angiogenesis HCC patients.

The future of metronomic chemotherapy: experimental and computational approaches of drug repurposing

Metronomic chemotherapy (MC), long-term continuous administration of anticancer drugs, is gaining attention as an alternative to the traditional maximum tolerated dose (MTD) chemotherapy. By combining MC with other treatments, the therapeutic efficacy is enhanced while minimizing toxicity. MC employs multiple mechanisms, making it a versatile approach against various cancers. However, drug resistance limits the long-term effectiveness of MC, necessitating ongoing development of anticancer drugs. Traditional drug discovery is lengthy and costly due to processes like target protein identification, virtual screening, lead optimization, and safety and efficacy evaluations. Drug repurposing (DR), which screens FDA-approved drugs for new uses, is emerging as a cost-effective alternative. Both experimental and computational methods, such as protein binding assays, in vitro cytotoxicity tests, structure-based screening, and several types of association analyses (Similarity-Based, Network-Based, and Target Gene), along with retrospective clinical analyses, are employed for virtual screening. This review covers the mechanisms of MC, its application in various cancers, DR strategies, examples of repurposed drugs, and the associated challenges and future directions.

Canine lung carcinoma-A descriptive review

Primary lung cancer is a relatively uncommon tumor in dogs, accounting for about 1% of all canine malignancies. Clinical signs in affected dogs can range from being asymptomatic to exhibiting chronic cough, and in rare cases, dyspnoea. Surgical excision of the primary tumor, along with resection of the affected locoregional lymph nodes is the preferred treatment option for most cases. Although chemotherapy, targeted therapy and radiation therapy have been employed, their effectiveness remain controversial. Dogs with stage T1 tumors can experience extended survival times of up to 2 years. However, the prognosis for dogs with advanced metastatic tumors is generally very poor. This review article discusses the etiology, clinical signs, diagnosis, staging, treatment options, and prognosis of primary lung carcinoma in dogs.

Durvalumab and tremelimumab in combination with metronomic oral vinorelbine for recurrent advanced cervical cancer: an open-label phase I/II study

BACKGROUND

The MOVIE phase I/II trial (NCT03518606) evaluated the safety and antitumor activity of durvalumab and tremelimumab combined with metronomic oral vinorelbine in patients with advanced tumors. We present the results of the recurrent advanced cervical cancer cohort.

METHODS

Patients received tremelimumab (intravenously, 75 mg, every four weeks (Q4W); four cycles max) plus durvalumab (intravenously, 1,500 mg, Q4W; 26 cycles max) and metronomic oral vinorelbine (40 mg, every three weeks (3QW)) until disease progression. The primary efficacy endpoint was the clinical benefit rate (CBR) based on the Response Evaluation Criteria in Solid Tumors V.1.1, which was analyzed using a Bayesian approach RESULTS: A total of 31 patients were enrolled and treated in the cervical cancer cohort. The median number of previous lines of chemotherapy for advanced disease was 2 (0-6), with all (100%) and 12 (38.7%) patients pretreated with cisplatin and bevacizumab, respectively. At the data cut-off, the median follow-up duration was 12.8 (Q1-Q3, 6.1-34.6) months. The CBR was 53.1% (95% CI, 36.0% to 69.8%), using a non-informative prior distribution (beta(1, 1)). The overall response rate was 41.9%, five patients achieved a complete response (16.1%), and eight patients (25.8%) had a partial response irrespective of histological subtype or programmed death-ligand 1 (PD-L1) expression. Of the 31 patients, 28 (90.3%) experienced treatment-related adverse events (TRAEs), 13 (41.9%) reported grade ≥3 immune-related adverse events (AEs), and 13 (41.9%) reported grade ≥3 chemotherapy-related AEs. The definitive discontinuation rate due to TRAEs was 16.1%.

CONCLUSIONS

Dual checkpoint blockade of PD-L1 and cytotoxic T-lymphocyte-associated antigen-4 combined with metronomic oral vinorelbine demonstrated meaningful and durable clinical activity in patients with previously treated advanced cervical cancer. Toxicity was significant but manageable.

Anlotinib in combination with metronomic chemotherapy in HER2-negative metastatic breast cancer: an observational and retrospective study

Anti-angiogenesis offers an important treatment strategy for metastatic breast cancer (MBC). Metronomic chemotherapy (MCT) provides antiangiogenic effects without increased toxicities, making it good partner for antiangiogenic therapy. We conducted the present retrospective study to evaluate the efficacy and safety of anlotinib plus MCT for HER2 negative MBC. Patients with HER2 negative MBC who received metronomic chemotherapy (Vinorelbine (NVB), Capecitabine (CAPE), Etoposide (VP-16)) with anlotinib were retrospectively analyzed from Jan 2019 to Dec 2021. The primary end point was progression free survival (PFS). Secondary end points included objective response rate (ORR), disease control rate (DCR), overall survival (OS) and safety. 48 patients with HER2 negative MBC were enrolled. 19 (39.6%) patients received NVB, 17 (35.4%) patients received CAPE and 12 (25.0%) patients received VP-16. The overall ORR and DCR were 8.3% (4/48) and 87.5% (42/48) respectively. The median PFS was 5.6 months (95% CI 4.3-7.0 months), and the median OS was 25.2 months (95% CI 20.2-30.1 months). The patients with age ≥ 50 (5.3 vs. 7.7 months, P = 0.014, HR = 0.407) and pathologic grade 1 or 2 (6.2 vs. 3.2 months, P = 0.023, HR = 2.471) had significantly longer PFS. The patients with hormone receptor (HR) positive (5.3 vs. 7.7 months, P = 0.004, HR = 0.206) and pathologic grade 1 or 2 (6.2 vs. 3.2 months, P = 0.020, HR = 3.882) had significantly longer OS. The incidence of all grades adverse events (AEs) was 56.3% (27/48) and grade 3-4 AEs was 12.5% (6/48). Within the context of real-world clinical practice, anlotinib in combination with metronomic chemotherapy provides a well-tolerated and effective treatment option for HER2-negative MBC, which warrants further investigation in the future.

Metronomic chemotherapy using capecitabine and cyclophosphamide in metastatic breast cancer - efficacy, tolerability and quality of life results from the phase II METRO trial

BACKGROUND

Chemotherapy is commonly used in metastatic breast cancer (MBC) to prolong life and improve quality of life (QoL). The optimal dosing and sequencing beyond the second line of treatment are unknown and pose a risk of overtreatment. Continuous low oral doses of metronomic chemotherapy using capecitabine 500 mg three times daily and cyclophosphamide 50 mg once daily (MCT-CX) may be an effective and tolerable treatment option for patients with MBC.

METHODS

In this open-label, single-arm single-centre phase II trial patients with MBC received MCT-CX until disease progression or unacceptable toxicity. The primary endpoint was the clinical benefit rate (CBR), defined as the proportion of participants with a best overall response of complete (CR) or partial response (PR) at any time, or stable disease (SD) for ≥24 weeks according to radiological evaluation. Toxicity was assessed according to the Common Toxicity Criteria v 4.0. QoL was assessed with the EORTC-30 questionnaire.

RESULTS

In total, 40 patients were included. Most participants (72 %) presented with visceral disease and received MCT-CX beyond the second line (58 %). The CBR was 45 % (8 PR and 10 SD ≥ 24 weeks). Toxicities were low grade with hand-foot syndrome being the most common. There was no significant change in QoL over the first 24 weeks.

CONCLUSION

MCT-CX is a plausible treatment option in far advanced breast cancer, with almost half of trial participants responding to treatment without QoL impairments.

Efficacy and safety of metronomic oral vinorelbine and its combination therapy as second- and later-line regimens for advanced non-small-cell lung cancer: a retrospective analysis

OBJECTIVE

This retrospective analysis aimed to evaluate the efficacy and adverse reactions of metronomic oral vinorelbine and its combination therapy as second- and later-line regimens for advanced non-small-cell lung cancer (NSCLC).

METHODS

NSCLC patients undergoing metronomic oral vinorelbine as second- and later-line regimens in Fujian Cancer Hospital from October 2018 to October 2022 were enrolled, and patients' demographic and clinical characteristics were collected. The efficacy and safety of metronomic oral vinorelbine monotherapy and its combination therapy regimens were compared.

RESULTS

Of 57 study subjects, 63.2% received third- and later-line therapy, with median progression-free survival (mPFS) of 4 months, overall response rate (ORR) of 10.5%, and disease control rate (DCR) of 80.7%. The incidence of therapy-related adverse events was 42.1%, and there was only one case presenting grades 3 and 4 adverse events (1.8%). Among driver gene-negative participants, vinorelbine combination therapy regimens achieved longer mPFS (4.6 vs. 1.2 months, hazards ratio = 0.11, P < 0.0001) and comparable toxicity in relative to metronomic oral vinorelbine, and metronomic oral vinorelbine combined with immune checkpoint inhibitors showed the highest response, with mPFS of 5.6 months (95% CI 4.8 to 6.4 months), ORR of 25%, and DCR of 81.3%. Among participants with gradual resistance to osimertinib, continuing osimertinib in combination with metronomic oral vinorelbine achieved mPFS of 6.3 months (95% CI 0.1 to 12.5 months) and DCR of 86.7%.

CONCLUSION

Metronomic oral vinorelbine and its combination therapy regimens are favorable options as second- and later-line therapy for advanced NSCLC patients, with acceptable efficacy and tolerable toxicity. Vinorelbine combination therapy regimens show higher efficacy and comparable toxicity in relative to metronomic oral vinorelbine, and metronomic oral vinorelbine may have a synergistic effect with immunotherapy and EGFR-TKI targeted therapy.

A mathematical framework for comparison of intermittent versus continuous adaptive chemotherapy dosing in cancer

Chemotherapy resistance in cancer remains a barrier to curative therapy in advanced disease. Dosing of chemotherapy is often chosen based on the maximum tolerated dosing principle; drugs that are more toxic to normal tissue are typically given in on-off cycles, whereas those with little toxicity are dosed daily. When intratumoral cell-cell competition between sensitive and resistant cells drives chemotherapy resistance development, it has been proposed that adaptive chemotherapy dosing regimens, whereby a drug is given intermittently at a fixed-dose or continuously at a variable dose based on tumor size, may lengthen progression-free survival over traditional dosing. Indeed, in mathematical models using modified Lotka-Volterra systems to study dose timing, rapid competitive release of the resistant population and tumor outgrowth is apparent when cytotoxic chemotherapy is maximally dosed. This effect is ameliorated with continuous (dose modulation) or intermittent (dose skipping) adaptive therapy in mathematical models and experimentally, however, direct comparison between these two modalities has been limited. Here, we develop a mathematical framework to formally analyze intermittent adaptive therapy in the context of bang-bang control theory. We prove that continuous adaptive therapy is superior to intermittent adaptive therapy in its robustness to uncertainty in initial conditions, time to disease progression, and cumulative toxicity. We additionally show that under certain conditions, resistant population extinction is possible under adaptive therapy or fixed-dose continuous therapy. Here, continuous fixed-dose therapy is more robust to uncertainty in initial conditions than adaptive therapy, suggesting an advantage of traditional dosing paradigms.

Intestinal ABC transporters: Influence on the metronomic cyclophosphamide-induced toxic effect in an obese mouse mammary cancer model

Metronomic chemotherapy (MCT) is a cancer therapeutic approach characterized by low dose drug chronic administration and limited or null toxicity. Obesity-induced metabolic alterations worsen cancer prognosis and influence the intestinal biochemical barrier, altering the Multidrug resistance-associated protein 2 (Mrp2) and Multidrug resistance protein-1 (Mdr-1), efflux pumps that transport chemotherapeutic drugs. Obesity and cancer are frequent co-morbidities; thus, our aim was to evaluate the effectiveness and toxicity of MCT with cyclophosphamide (Cy) in obese mice with metabolic alterations bearing a mammary adenocarcinoma. Simultaneously, the expression and activities of intestinal Mrp2 and Mdr-1 were assessed. CBi male mice, were fed with chow diet (C) or diet with 40 % of fat (HFD). After 16 weeks, metabolic alterations were confirmed by biochemical and morphological parameters. At that time-point, HFD group showed decreased expressions of Mrp2 mRNA (53 %) as well as Mdr-1a and Mdr-1b (42 % and 59 %, respectively), compared to C (P < 0.05). This result correlated with decreased intestinal Mrp2 and Mdr-1 efflux activities (64 % and 45 %, respectively), compared to C (P < 0.05). Ultimately, mice were challenged with M-406 mammary adenocarcinoma; when the tumor was palpable, mice were distributed into 4 groups. The % inhibition of tumor growth with Cy (30 mg/kg/day) in C + Cy was higher than that of HFD + Cy (P = 0.052). Besides, it was observed a 21 % diminution in body weight and leukopenia in the HFD + Cy group. Conclusion: Obesity-induced metabolic alterations impair intestinal Mrp2 and Mdr-1 functions, bringing about increments in Cy absorption, leading to toxicity; in addition, the antitumor effectiveness of MCT decreased in obese animals.

Pyrotinib combined with metronomic etoposide in heavily pretreated HER2-positive metastatic breast cancer: a single-arm, phase II study

BACKGROUND

Exploration of novel combination mode of pyrotinib and chemotherapy for heavily pretreated HER2-positive metastatic breast cancer (MBC) and how to balance survival benefits and compliance are still urgent problems in clinical practice. The current single-arm prospective phase II study aimed to evaluate the efficacy and safety of pyrotinib in combination with metronomic oral etoposide in heavily pretreated HER2-positive MBC.

METHODS

HER2-positive MBC patients previously treated with trastuzumab were enrolled to receive oral pyrotinib 400 mg per day and metronomic oral etoposide 50 mg per day d1-21 every 28 days, until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). The secondary endpoints were objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), overall survival (OS), and safety.

RESULTS

22 patients were enrolled with a median of 4 prior treatment regimens for MBC. During the follow-up of 20 evaluable patients, the median PFS was 9.0 months (95% CI, 7.6-10.4 months), and the median OS was 27.0 months (95%CI, 20.9-33.1 months). The ORR was 30% (6/20), the DCR was 80% (16/20), and the CBR was 65% (13/20). The most common grade 3 adverse events (AEs) included nausea (15%), vomiting (15%), diarrhea (5%), anemia (5%), and peripheral neuropathy (5%). No grade 4 or lethal AEs were observed.

CONCLUSION

The combination of pyrotinib with metronomic oral etoposide has achieved promising clinical benefits in heavily pretreated HER2-positive MBC, with acceptable and manageable toxicity.

TRIAL REGISTRATION

Registry number: NCT03923179. Registered April 18, 2019.

Synergistic effects of herpes oncolytic virus and cyclophosphamide for recurrent malignant glioma: a narrative review

Gliomas, comprising nearly 80% of brain malignancies, present a formidable challenge with glioblastomas being the most aggressive subtype. Despite multidisciplinary care, including surgery and chemoradiotherapy, the prognosis remains grim, emphasizing the need for innovative treatment strategies. The blood-brain barrier complicates drug access, and the diverse histopathology hinders targeted therapies. Oncolytic herpes viruses (oHSVs), particularly HSV1716, G207, and rQNestin34.5v, show promise in glioma treatment by selectively replicating in tumor cells. Preclinical and clinical studies demonstrate the safety and efficacy of oHSVs, with T-Vec being FDA-approved. However, challenges like viral delivery limitations and antiviral responses persist. The combination of oHSVs and combining cyclophosphamide (CPA) addresses these challenges, demonstrating increased transgene expression and viral activity. The immunosuppressive properties of CPA, particularly in metronomic schedules, enhance oHSV efficacy, supporting the development of this combination for recurrent malignant gliomas. CPA with oHSVs enhances viral oncolysis and extends survival. CPA's immunomodulatory effects, suppressing regulatory T cells, improve oHSV efficiency. While obstacles remain, this synergistic approach offers hope for improved outcomes, necessitating further research and clinical validation.

The inherent fragility of collective proliferative control

Tissues achieve and maintain their sizes through active feedback, whereby cells collectively regulate proliferation and differentiation so as to facilitate homeostasis and the ability to respond to disturbances. One of the best understood feedback mechanisms-renewal control-achieves remarkable feats of robustness in determining and maintaining desired sizes. Yet in a variety of biologically relevant situations, we show that stochastic effects should cause rare but catastrophic failures of renewal control. We define the circumstances under which this occurs and raise the possibility such events account for important non-genetic steps in the development of cancer. We further suggest that the spontaneous stochastic reversal of these events could explain cases of cancer normalization or dormancy following treatment. Indeed, we show that the kinetics of post-treatment recurrence for many cancers are often better fit by a model of stochastic re-emergence due to loss of collective proliferative control, than by deterministic models of cancer relapse.

Molecular Iodine Improves the Efficacy and Reduces the Side Effects of Metronomic Cyclophosphamide Treatment against Mammary Cancer Progression

Metronomic chemotherapy with cyclophosphamide (Cpp) has shown promising results in cancer protocols. These lower and prolonged doses have antiangiogenic, pro-cytotoxic, and moderate secondary effects. Molecular iodine (I2) reduces the viability of cancer cells and, with chemotherapeutic agents, activates the antitumoral immune response and diminishes side effects. The present work evaluates the adjuvant of oral I2 with Cpp using a murine model of mammary cancer. Female Sprague Dawley rats with 7,12-dimethylbenzantracene-induced tumors received Cpp intraperitoneal (50 and 70 mg/kg two times/week, iCpp50 and iCpp70) and oral (0.03%; 50 mg/Kg; oCpp50) doses. I2 (0.05%, 50 mg/100 mL) and oCpp50 were offered in drinking water for three weeks. iCpp70 was the most efficient antitumoral dose but generated severe body weight loss and hemorrhagic cystitis (HC). I2 prevented body weight loss, exhibited adjuvant actions with Cpp, decreasing tumor growth, and canceled HC mechanisms, including decreases in vascular endothelial growth factor (VEGF) and Survivin expression. oCpp50 + I2 diminished angiogenic signals (CD34, vessel-length, and VEGF content) and proinflammatory cytokines (interleukin-10 and tumor necrosis factor-alpha) and increased cytotoxic (lymphocytic infiltration, CD8+ cells, Tbet, and interferon-gamma) and antioxidant markers (nuclear erythroid factor-2 and glutathione peroxidase). I2 enhances the effectiveness of oCpp, making it a compelling candidate for a clinical protocol.

Promotion of tumor angiogenesis and growth induced by low-dose antineoplastic agents via bone-marrow-derived cells in tumor tissues

Background

More research is needed to solidify the basis for reasonable metronomic chemotherapy regimens due to the inconsistent clinical outcomes from studies on metronomic chemotherapy with antineoplastic agents, along with signs of a nonlinear dose-response relationship at low doses. The present study therefore explored the dose-response relationships of representative antineoplastic agents in low dose ranges and their underlying mechanisms.

Methods

Cyclophosphamide (CPA) and 5-fluorouracil (5-Fu) were employed to observe the effects of the frequent administration of low-dose antineoplastic agents on tumor growth, tumor angiogenesis, and bone-marrow-derived cell (BMDC) mobilization in mouse models. The effects of antineoplastic agents on tumor and endothelial cell functions with or without BMDCs were analyzed in vitro.

Results

Tumor growth and metastasis were significantly promoted after the administration of CPA or 5-Fu at certain low dose ranges, and were accompanied by enhanced tumor angiogenesis and proangiogenic factor expression in tumor tissues, increased proangiogenic BMDC release in the circulating blood, and augmented proangiogenic BMDC retention in tumor tissues. Low concentrations of CPA or 5-Fu were found to significantly promote tumor cell migration and invasion, and enhance BMDC adhesion to endothelial cells in vitro.

Conclusion

These results suggest that there are risks in empirical metronomic chemotherapy using low-dose antineoplastic agents and the optimal dosage and administration schedule of antineoplastic agents need to be determined through further research.

Parthenolide enhances the metronomic chemotherapy effect of cyclophosphamide in lung cancer by inhibiting the NF-kB signaling pathway

BACKGROUND

Parthenolide (PTL), a sesquiterpene lactone derived from the medicinal herb Chrysanthemum parthenium, exhibits various biological effects by targeting NF-kB, STAT3, and other pathways. It has emerged as a promising adjunct therapy for multiple malignancies.

AIM

To evaluate the in vitro and in vivo effect of PTL on cyclophosphamide (CTX) metronomic chemotherapy.

METHODS

The cytotoxicity of PTL and CTX on Lewis lung cancer cells (LLC cells) was assessed by measuring cell activity and apoptosis. The anti-tumor efficiency was evaluated using a tumor xenograft mice model, and the survival of mice and tumor volume were monitored. Additionally, the collected tumor tissues were analyzed for tumor microenvironment indicators and inflammatory factors.

RESULTS

In vitro, PTL demonstrated a synergistic effect with CTX in inhibiting the growth of LLC cells and promoting apoptosis. In vivo, metronomic chemotherapy combined with PTL and CTX improved the survival rate of tumor-bearing mice and reduced tumor growth rate. Furthermore, metronomic chemotherapy combined with PTL and CTX reduced NF-κB activation and improved the tumor immune microenvironment by decreasing tumor angiogenesis, reducing Transforming growth factor β, and α-SMA positive cells.

CONCLUSION

PTL is an efficient compound that enhances the metronomic chemotherapy effects of CTX both in vitro and in vivo, suggesting its potential as a supplementary therapeutic strategy in metronomic chemotherapy to improve the chemotherapy effects.

A retrospective, real-life analysis of metronomic oral single-agent cyclophosphamide for the treatment of platinum-pretreated advanced ovarian carcinoma in Italy

INTRODUCTION

Metronomic oral cyclophosphamide (MOC) presents many potential advantages, such as significantly less severe side effects than standard regimens, ease of administration, and the delivery of a dose-dense but not necessarily dose-intense treatment. These observations prompted us to evaluate in a retrospective, multicenter study the efficacy and toxicity of MOC in a real-life series of pretreated cancer patients.

METHODS

The study is a multicenter, retrospective analysis of the activity of single-agent MOC in patients with recurrent or residual epithelial ovarian, fallopian tube, or primary. Eligible patients were continuously treated with MOC at 50 mg/day until progression, toxicity, or death. Overall response rate (ORR), stable disease (SD), and disease control rate (DCR) were reported.

RESULTS

The study included 62 patients. Three patients reached a complete response rate (5%), 11 had a partial response rate (18), and 15 had stabilization of disease (24) for an ORR of 23% and a DCR of 47%. Patients with low-grade indolent tumors showed an ORR and an SD rate higher than that observed in non-indolent ones (33% vs. 18% and 28% vs. 14%, respectively). Overall, progression-free survival was 3.5 months (range 1-9 months).

CONCLUSION

Single-agent MOC is active and very well tolerated in a significant fraction of patients with refractory, recurrent, or residual epithelial ovarian, fallopian tube, or primary peritoneal cancer. In the vision of a practical approach, single-agent MOC may be a useful palliative treatment option for patients with poor tolerance to high-dose regimens or widely pretreated. Further studies are needed better to characterize the role of such an approach in clinical practice.

Metronomic Chemotherapy for Pediatric Refractory Solid Tumors: A Retrospective Single-center Study

Metronomic chemotherapy (MC) is based on chronic administration of chemotherapeutic agents at minimally toxic doses without prolonged drug-free breaks, that inhibits tumor angiogenesis and induces tumor dormancy. This study aimed to determine the efficacy of MC for pediatric refractory solid tumors. We retrospectively analyzed the data of pediatric patients with relapsed/refractory solid tumors who received treatment, including low-dose continuous administration of anticancer drugs, at our institute. Of the 18 patients, the disease statuses at the initiation of MC were complete remission (n=2), partial remission/stable disease (n=5), and progressive disease (n=11). The overall survival rate was 61% at 12 months and 34% at 24 months, and the progression-free survival rate was 21% at 12 and 24 months. Although only 5 of the 18 patients showed certain tumor regression or maintained remission, tumors that stabilized, maintained remission/stable disease, and showed certain advantages in terms of overall survival rate, even if limited to progressive disease. Approximately half of the patients demonstrated temporal tumor stabilization and improved survival time. Overall, previous reports and the present study support the conclusion that MC has the potential to play an important role in pediatric cancer treatment during the advanced stage.

Metronomic chemotherapy: bridging theory to clinical application in canine and feline oncology

Veterinary oncology has experienced significant evolution over the last few decades, with chemotherapy being currently applied to several neoplasms with therapeutic success. Traditionally, chemotherapy protocols are based on classic cytostatic drugs under the concept of maximum tolerated dose (MTD), which has been associated with a greater risk of toxicity and resistance. Thus, new therapeutic alternatives have emerged, such as metronomic chemotherapy (MC), introducing a new paradigm in cancer treatment. MC consists of administering low doses of chemotherapy drugs continuously over a long period of time, modulating the tumour microenvironment (TME) due to the combination of cytotoxic, antiangiogenic and immunomodulatory effects. This multi-targeted therapy has been described as a treatment option in several canine and feline cancers since 2007, with positive results already published in the literature, particularly in mammary carcinomas and soft tissue sarcomas in dogs. The aim of this review article is to describe the current knowledge about the use of MC in small animal oncology, with emphasis on its mechanisms of action, the most commonly used drugs and clinical outcome.

Metronomic chemotherapy in cancer treatment: new wine in an old bottle

Over the past two decades, metronomic chemotherapy has gained considerable attention and has demonstrated remarkable success in the treatment of cancer. Through chronic administration and low-dose regimens, metronomic chemotherapy is associated with fewer adverse events but still effectively induces disease control. The identification of its antiangiogenic properties, direct impact on cancer cells, immunomodulatory effects on the tumour microenvironment, and metabolic reprogramming ability has established the intrinsic multitargeted nature of this therapeutic approach. Recently, the utilization of metronomic chemotherapy has evolved from salvage treatment for metastatic disease to adjuvant maintenance therapy for high-risk cancer patients, which has been prompted by the success of several substantial phase III trials. In this review, we delve into the mechanisms underlying the antitumour effects of metronomic chemotherapy and provide insights into potential combinations with other therapies for the treatment of various malignancies. Additionally, we discuss health-economic advantages and candidates for the utilization of this treatment option.

A mathematical model to study low-dose metronomic scheduling for chemotherapy

Metronomic chemotherapy refers to the frequent administration of chemotherapeutic agents at a lower dose and presents an attractive alternative to conventional chemotherapy with encouraging response rates. However, the schedule of the therapy, including the dosage of the drug, is usually based on empiricism. The confounding effects of tumor-endothelial-immune interactions during metronomic administration of drugs have not yet been explored in detail, resulting in an incomplete assessment of drug dose and frequency evaluations. The present study aimed to gain a mechanistic understanding of different actions of metronomic chemotherapy using a mathematical model. We have established an analytical condition for determining the dosage and frequency of the drug depending on its clearance rate for complete tumor elimination. The model also brings forward the immune-mediated clearance of the tumor during the metronomic administration of the chemotherapeutic agent. The results from the global sensitivity analysis showed an increase in the sensitivity of drug and immune-mediated killing factors toward the tumor population during metronomic scheduling. Our results emphasize metronomic scheduling over the maximum tolerated dose (MTD) and define a model-based approach for approximating the optimal schedule of drug administration to eliminate tumors while minimizing harm to the immune cells and the patient's body.

Phase II randomized trial comparing metronomic anthracycline-containing chemotherapy versus standard schedule in untreated HER2 negative advanced breast cancer: activity and quality of life results of the GOIM 21003 trial

BACKGROUND

Optimizing chemotherapy to achieve disease and symptoms control is a noteworthy purpose in advanced breast cancer (ABC). We reported the activity and quality of life of a phase II study, comparing metronomic regimen with standard schedule as first line chemotherapy for ABC.

METHODS

Patients with HER2 negative ABC were randomized to non-pegylated liposomal doxorubicin (NPLD, 60 mg/m2 every 3 weeks) and cyclophosphamide (CTX, 600 mg/m2 every 3 weeks) (Arm A) or NPLD (20 mg/m2 day, on day 1, 8 and 15 every 4 weeks) and metronomic daily oral CTX 50 mg (ARM B). Primary end-points were overall response rate (ORR) and quality of life, secondary progression-free survival (PFS), overall survival (OS) and toxicity.

RESULTS

From August 2012 to December 2017, 121 patients were enrolled, 105 evaluable. Median follow-up was 21.3 months. Most patients had hormone receptor positive. ORR was 43 % in arm A and 50 % in arm B. Median PFS was 8.9 months in arm A and 6,4 months in arm B. There was no difference in OS. Total score was not clinically different between the two arms. Grade 4 neutropenia was observed in 12 patients and 16 patients respectively; alopecia G2 in 41 % (77 %) vs 14 (27 %) in arm A and in arm B respectively. One cardiac toxicity was observed (arm A).

CONCLUSIONS

First line metronomic chemotherapy for HER2 negative ABC had similar clinical activity and quite better tolerability than standard schedule and could be considered a further treatment option when chemotherapy is indicated.

Optimizing cancer therapy: a review of the multifaceted effects of metronomic chemotherapy

Metronomic chemotherapy (MCT), characterized by the continuous administration of chemotherapeutics at a lower dose without prolonged drug-free periods, has garnered significant attention over the last 2 decades. Extensive evidence from both pre-clinical and clinical settings indicates that MCT induces distinct biological effects than the standard Maximum Tolerated Dose (MTD) chemotherapy. The low toxicity profile, reduced likelihood of inducing acquired therapeutic resistance, and low cost of MCT render it an attractive chemotherapeutic regimen option. One of the most prominent aspects of MCT is its anti-angiogenesis effects. It has been shown to stimulate the expression of anti-angiogenic molecules, thereby inhibiting angiogenesis. In addition, MCT has been shown to decrease the regulatory T-cell population and promote anti-tumor immune response through inducing dendritic cell maturation and increasing the number of cytotoxic T-cells. Combination therapies utilizing MCT along with oncolytic virotherapy, radiotherapy or other chemotherapeutic regimens have been studied extensively. This review provides an overview of the current status of MCT research and the established mechanisms of action of MCT treatment and also offers insights into potential avenues of development for MCT in the future.

Heat shock protein paradigms in cancer progression: future therapeutic perspectives

Heat-shock proteins (HSPs), also known as stress proteins, are ubiquitously present in all forms of life. They play pivotal roles in protein folding and unfolding, the formation of multiprotein complexes, the transportation and sorting of proteins into their designated subcellular compartments, the regulation of the cell cycle, and signalling processes. These HSPs encompass HSP27, HSP40, HSP70, HSP60, and HSP90, each contributing to various cellular functions. In the context of cancer, HSPs exert influence by either inhibiting or activating diverse signalling pathways, thereby impacting growth, differentiation, and cell division. This article offers an extensive exploration of the functions of HSPs within the realms of pharmacology and cancer biology. HSPs are believed to play substantial roles in the mechanisms underlying the initiation and progression of cancer. They hold promise as valuable clinical markers for cancer diagnosis, potential targets for therapeutic interventions, and indicators of disease progression. In times of cellular stress, HSPs function as molecular chaperones, safeguarding the structural and functional integrity of proteins and aiding in their proper folding. Moreover, HSPs play a crucial role in cancer growth, by regulating processes such as angiogenesis, cell proliferation, migration, invasion, and metastasis.

Metronomic chemotherapy and drug repurposing: A paradigm shift in oncology

Cancer represents a significant global health and economic burden due to its high mortality rates. While effective in some instances, traditional chemotherapy often falls short of entirely eradicating various types of cancer. It can cause severe side effects due to harm to healthy cells. Two therapeutic approaches have risen to the forefront to address these limitations: metronomic chemotherapy (MCT) and drug repurposing. Metronomic chemotherapy is an innovative approach that breaks from traditional models. It involves the administration of chemotherapeutic regimens at lower doses, without long drug-free intervals that have previously been a hallmark of such treatments. This method offers a significant reduction in side effects and improved disease management. Simultaneously, drug repurposing has gained considerable attraction in cancer treatment. This approach involves utilizing existing drugs, initially developed for other therapeutic purposes, as potential cancer treatments. The application of known drugs in a new context accelerates the timeline from laboratory to patient due to pre-existing safety and dosage data. The intersection of these two strategies gives rise to a novel therapeutic approach named 'Metronomics.' This approach encapsulates the benefits of both MCT and drug repurposing, leading to reduced toxicity, potential for oral administration, improved patient quality of life, accelerated clinical implementation, and enhanced affordability. Numerous clinical studies have endorsed the efficacy of metronomic chemotherapy with tolerable side effects, underlining the potential of Metronomics in better cancer management, particularly in low- and middle-income countries. This review underscores the benefits and applications of metronomic chemotherapy and drug repurposing, specifically in the context of breast cancer, showcasing the promising results of pre-clinical and clinical studies. However, we acknowledge the necessity of additional clinical investigations to definitively establish the role of metronomic chemotherapy in conjunction with other treatments in comprehensive cancer management.

Dose-dependent bidirectional pharmacological effects of vinorelbine-based metronomic combination chemotherapy on tumor growth and metastasis and mechanisms in melanoma mouse model

BACKGROUND

There is evidence that the empirical setting of doses and schedules of antineoplastic agents in metronomic chemotherapy (MC) might lead to undesirable outcomes, such as promoting tumor growth or metastasis at certain low doses. However, details about the dose effect of antineoplastic agents in MC have not been fully known yet.

OBJECTIVES

Vinorelbine combined with cisplatin or fluorouracil (VNR/CDDP or VNR/FU) was selected to investigate its effects on tumor growth or metastasis as well as mechanisms.

METHODS

Experimental techniques, including immunohistochemistry, western blot, immunofluorescence, and flow cytometry, were used to explore the mechanisms, along with cell proliferation, apoptosis, migration, and invasion.

RESULTS

The results showed that VNR/CDDP or VNR/FU promoted tumor growth and metastasis at low doses and inhibited them at high ones. Except that expressions of apoptotic proteins were elevated at both low and high doses, low-dose treatments enhanced angiogenesis and promoted the mobilization and recruitment of myeloid-derived suppressor cells (MDSCs), while high-dose treatments reversed these effects. Additionally, low concentrations of VNR/CDDP or VNR/FU stimulated tumor cell functions such as anti-apoptosis, migration, and invasion, but high concentrations only suppressed cell proliferation and increased apoptosis.

CONCLUSION

This study elucidated a bidirectional action mode regulated by multiple mechanisms at different doses in MC and also highlighted the risks of low-dose metronomic administration of antineoplastic agents in the clinic. More preclinical and clinical studies focusing on the dose-effect of metronomic regimens are urgently needed because an effective therapeutic regimen should be an optimal setting of drugs, doses, schedules, or combinations.

Low-dose metronomic cisplatin as an antiangiogenic and anti-inflammatory strategy for cancer

BACKGROUND

Conventional chemotherapy is based on the maximum tolerated dose (MTD) and requires treatment-free intervals to restore normal host cells. MTD chemotherapy may induce angiogenesis or immunosuppressive cell infiltration during treatment-free intervals. Low-dose metronomic (LDM) chemotherapy is defined as frequent administration at lower doses and causes less inflammatory change, whereas MTD chemotherapy induces an inflammatory change. Although several LDM regimens have been applied, LDM cisplatin (CDDP) has been rarely reported. This study addressed the efficacy of LDM CDDP on tumour endothelial cell phenotypic alteration compared to MTD CDDP.

METHODS

Tumour growth and metastasis were assessed in bladder cancer-bearing mice treated with LDM or MTD gemcitabine (GEM) and CDDP. To elucidate the therapeutic effects of LDM CDDP, the change of tumour vasculature, tumour-infiltrating immune cells and inflammatory changes were evaluated by histological analysis and mRNA expression in tumour tissues.

RESULTS

Tumour growth and bone metastasis were more suppressed by LDM CDDP + MTD GEM treatment than MTD CDDP + MTD GEM. Myeloid-derived suppressor cell accumulation was reduced by LDM CDDP, whereas inflammatory change was induced in the tumour microenvironment by MTD CDDP.

CONCLUSION

LDM CDDP does not cause inflammatory change unlike MTD CDDP, suggesting that it is a promising strategy in chemotherapy.

A randomized phase II study of metronomic cyclophosphamide and methotrexate (CM) with or without bevacizumab in patients with advanced breast cancer

PURPOSE

Metronomic chemotherapy has the potential to offer tumor control with reduced toxicity when compared to standard dose chemotherapy in patients with metastatic breast cancer. As metronomic chemotherapy may target the tumor microvasculature, it has the potential for synergistic effects with antiangiogenic agents such as the VEGF-A inhibitor bevacizumab.

METHODS

In this randomized phase II study, patients with metastatic breast cancer were randomized to receive metronomic oral cyclophosphamide and methotrexate (CM) combined with bevacizumab (Arm A) or CM alone (Arm B). The primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), and safety and tolerability.

RESULTS

A total of 55 patients were enrolled, with 34 patients treated on Arm A and 21 patients treated on Arm B. The ORR was modestly higher in Arm A (26%) than in Arm B (10%); neither met the 40% cutoff for further clinical evaluation. The median time to progression (TTP) was 5.52 months (3.22-13.6) on Arm A and 1.82 months (1.54-6.70) on Arm B (log-rank p = 0.008). The median OS was 29.6 months (17.2-NA) on Arm A and 16.2 months (15.7-NA) on Arm B (log-rank p = 0.7). Common all-grade adverse events in both arms included nausea, fatigue, and elevated AST.

CONCLUSION

The combination of metronomic CM with bevacizumab significantly improved PFS over CM alone, although there was no significant difference in OS. Oral metronomic chemotherapy alone has limited activity in advanced breast cancer.

CLINICALTRIALS

gov Identifier: NCT00083031. Date of Registration: May 17, 2004.

A review and metanalysis of metronomic oral single-agent cyclophosphamide for treating advanced ovarian carcinoma in the era of precision medicine

OBJECTIVE

Oral metronomic cyclophosphamide has been used as a single agent or in combination with other drugs for several solid tumors with interesting results in disease palliation and mild to moderate toxicity, notably in patients with recurrent epithelial ovarian cancer (EOC) progressing after systemic chemotherapy. In this paper, we report a review and a metanalysis of heterogeneous data published up to date.

DATA SOURCES

The literature search was restricted to single-agent MOC. The analysis was conducted through March 2023 by consulting PubMed, Embase, Google Scholar, and The Cochrane Library databases. Research string and Medical Subject Headings included "ovarian tumor," "ovarian carcinoma," or "ovarian cancer," "fallopian tube cancer," "primary peritoneal cancer," "oral chemotherapy," and "metronomic cyclophosphamide." All articles were assessed for quality by at least two investigators independently, and a < 18 patients sample size cutoff was chosen as a lower limit with a Cohen's kappa statistical coefficient for accuracy and reliability. Metanalysis of selected papers was carried out according to a fixed model.

DATA SUMMARY

The percentage of agreement between investigators on literature study selection was very high, reaching 96.9% with a Cohen's k of 0.929. MOC pooled objective response rate (ORR) and disease control rate for recurrent or platinum-refractory ovarian cancer were 18.8% (range 4-44%) and 36.2% (range 16-58.8%), respectively. The mean progressive-free survival and overall survival were 3.16 months (range 1.9 to 5.0 months) and 8.7 months (range 8 to 13 months), respectively. The fixed model metanalysis of selected studies showed a 16% median ORR (12-20% CI, p < 0.001).

CONCLUSIONS

Single-agent oral cyclophosphamide in EOC holds promise as a treatment option, even in the era of precision medicine. Genetic factors, such as DNA repair gene polymorphisms, may influence treatment response. Combining cyclophosphamide with biological agents such as PARP inhibitors or immunotherapy agents is an area of active investigation.

Multifunctional nano MOF drug delivery platform in combination therapy

Recent preclinical and clinical studies have demonstrated that for cancer treatment, combination therapies are more effective than monotherapies in reducing drug-related toxicity, decreasing drug resistance, and improving therapeutic efficacy. With the rapid development of nanotechnology, the combination of metal-organic frameworks (MOFs) and multi-mode therapy offers a realistic possibility to further improve the shortcomings of cancer treatment. This article focuses on the latest developments, achievements, and treatment strategies of representative multifunctional MOF combination therapies for cancer treatment in recent years, which include not only bimodal combination therapies, but also multi-modal synergistic therapies, further demonstrating the effectiveness and superiority of the MOF drug delivery systems in cancer treatment.

Metronomic chemotherapy in ovarian cancer

Translational research and the development of targeted therapies have transformed the therapeutic landscape in epithelial ovarian cancer over the last decade. However, recurrent ovarian cancer continues to pose formidable challenges to therapeutic interventions, necessitating innovative strategies to optimize treatment outcomes. Current research focuses on the development of pharmaceuticals that target potential resistance pathways to DNA repair pathways. However, the cost and toxicity of some of these therapies are prohibitive and majority of patients lack access to clinical trials. Metronomic chemotherapy, characterized by the continuous administration of low doses of chemotherapeutic agents without long treatment breaks, has emerged as a promising approach with potential implications beyond recurrent setting. It acts primarily by inhibition of angiogenesis and activation of host immune system. We here review the mechanism of action of metronomic chemotherapy, as well as its current role, limitations, and avenues for further research in the management of epithelial ovarian cancer.

Metronomic chemotherapy, dampening of immunosuppressive cells, antigen presenting cell activation, and T cells. A quartet against refractoriness and resistance to checkpoint inhibitors

Chemotherapeutic agents have profound effects on cancer, stroma and immune cells that - in most cases - depend upon the dosage and schedule of administration. Preclinical and clinical studies summarized and discussed in the present review have demonstrated that maximum tolerable dosage (MTD) vs low-dosage, continuous (metronomic) administration of most chemotherapeutics have polarized effects on immune cells. In particular, metronomic schedules might be associated - among others effects - with activation of antigen presenting cells and generation of new T cell clones to enhance the activity of several types of immunotherapies. Ongoing and planned clinical trials in different types of cancer will confirm or dismiss this hypothesis and provide candidate biomarker data for the selection of patients who are likely to benefit from these combinatorial strategies.

Global trajectory and future prospects of metronomic chemotherapy research: A scientometric analysis (2000-2022)

This scientometric study aimed to provide a first comprehensive overview of the global research landscape of Metronomic Chemotherapy (MC) from 2000 to 2022 using a data-driven approach to identify key trends, collaborations, and potential opportunities. This study highlights the increasing prevalence of MC, with annual outputs increasing substantially over the same timeframe. The United States contributed the most to MC research, followed by Italy and China, while there was a lack of collaborative research efforts between countries and organizations. Through keyword co-occurrence analysis, we identified emerging interdisciplinary research areas, such as "nanoparticles," "immunotherapy," and "antitumor immunity." Our citation analysis identified the most influential authors, institutions, and journals, providing a comprehensive overview of the structure of knowledge and dissemination of MC research. Although the number of publications has decreased since 2019, the analysis indicates that this field has received substantial scholarly attention. These discoveries are extremely important for researchers, funding organizations, and policymakers because they highlight the need for more collaboration, interdisciplinary approaches, and resource allocation in underrepresented fields. This study concludes with recommendations for guiding future research and collaboration, resulting in a larger impact and fostering substantial advancements in MC research.

Hormetic and synergistic effects of cancer treatments revealed by modelling combinations of radio - or chemotherapy with immunotherapy

BACKGROUND

Radio/chemotherapy and immune systems provide examples of hormesis, as tumours can be stimulated (or reduced) at low radio/chemical or antibody doses but inhibited (or stimulated) by high doses.

METHODS

Interactions between effector cells, tumour cells and cytokines with pulsed radio/chemo-immunotherapy were modelled using a pulse differential system.

RESULTS

Our results show that radio/chemotherapy (dose) response curves (RCRC) and/or immune response curves (IRC) or a combination of both, undergo homeostatic changes or catastrophic shifts revealing hormesis in many parameter regions. Some mixed response curves had multiple humps, posing challenges for interpretation of clinical trials and experimental design, due to a fuzzy region between an hormetic zone and the toxic threshold. Mixed response curves from two parameter bifurcation analyses demonstrated that low-dose radio/chemotherapy and strong immunotherapy counteract side-effects of radio/chemotherapy on effector cells and cytokines and stimulate effects of immunotherapy on tumour growth. The implications for clinical applications were confirmed by good fits to our model of RCRC and IRC data.

CONCLUSIONS

The combination of low-dose radio/chemotherapy and high-dose immunotherapy is very effective for many solid tumours. The net benefit and synergistic effect of combined therapy is conducive to the treatment and inhibition of tumour cells.

Treatment of evolving cancers will require dynamic decision support

Cancer research has traditionally focused on developing new agents, but an underexplored question is that of the dose and frequency of existing drugs. Based on the modus operandi established in the early days of chemotherapies, most drugs are administered according to predetermined schedules that seek to deliver the maximum tolerated dose and are only adjusted for toxicity. However, we believe that the complex, evolving nature of cancer requires a more dynamic and personalized approach. Chronicling the milestones of the field, we show that the impact of schedule choice crucially depends on processes driving treatment response and failure. As such, cancer heterogeneity and evolution dictate that a one-size-fits-all solution is unlikely-instead, each patient should be mapped to the strategy that best matches their current disease characteristics and treatment objectives (i.e. their 'tumorscape'). To achieve this level of personalization, we need mathematical modeling. In this perspective, we propose a five-step 'Adaptive Dosing Adjusted for Personalized Tumorscapes (ADAPT)' paradigm to integrate data and understanding across scales and derive dynamic and personalized schedules. We conclude with promising examples of model-guided schedule personalization and a call to action to address key outstanding challenges surrounding data collection, model development, and integration.

Low-dose metronomic chemotherapy triggers oxidized mtDNA sensing inside tumor cells to potentiate CD8+T anti-tumor immunity

Low-dose metronomic (LDM) chemotherapy, the frequent and continuous use of low doses of conventional chemotherapeutics, is emerging as a promising form of chemotherapy utilization. LDM chemotherapy exerts immunomodulatory effects. However, the underlying mechanism is not fully understood. Here we found that suppressing tumor growth by LDM chemotherapy was dependent on the activation of CD8+T cells. LDM chemotherapy potentiated the cytotoxic function of CD8+T cells by stimulating cancer-cell autonomous type I interferon (IFN) induction. Mechanistically, LDM chemotherapy evoked mitochondrial dysfunction and increased reactive oxygen species (ROS) production. ROS triggered the oxidation of cytosolic mtDNA, which was sensed by cGAS-STING, consequently inducing type I IFN production in the cancer cells. Moreover, the cGAS-STING-IFN axis increased PD-L1 expression and predicted favorable clinical responses to chemoimmunotherapy. Antioxidant N-acetylcysteine inhibited oxidized mtDNA-induced type I IFN production and attenuated the efficacy of combination therapy with LDM chemotherapy and PD-L1 blockade. This study elucidates the critical role of intratumoral oxidized mtDNA sensing in LDM chemotherapy-mediated activation of CD8+T cell immune response. These findings may provide new insights for designing combinatorial immunotherapy for cancer patients.

Using oral tegafur/uracil (UFT) plus leucovorin as adjuvant chemotherapy in stage II colorectal cancer: a propensity score matching study from Taiwan

BACKGROUND

Early-stage colorectal cancer had excellent outcomes after curative resection, typically. However, a perplexing survival paradox between stage II and stage III was noted. This paradox could be influenced by the administration of routine postoperative adjuvant chemotherapy and the presence of high-risk factors in stage II CRC. The objective of the study was to investigate the influence of high-risk factors on patients with stage II CRC and assess the efficacy of oral tegafur/uracil (UFT) plus leucovorin as adjuvant chemotherapy for stage II CRC patients.

METHODS

A retrospective study was conducted using propensity score matching at a single medical institution. A total of 1544 patients with stage II colorectal cancer who underwent radical surgery between January 2004 and January 2009 were included. The intervention used was tegafur/uracil plus leucovorin as adjuvant chemotherapy. The main outcome measures were disease-free survival and overall survival.

RESULTS

After propensity score matching, 261 patients were included in three groups: no-treatment, half-year treatment, and one-year treatment. The clinical characteristics of each group tended to be more consistent. The Cox proportional hazard models showed that tegafur/uracil treatment or not was a significant independent factor for oncological outcome. Kaplan-Meier analysis also showed significantly better disease-free survival and overall survival. Further investigation revealed that tegafur/uracil duration was an independent factor for oncological outcome. While the survival curve did not reach statistical significance, the one-year UFT treatment group demonstrated the best treatment trend.

CONCLUSIONS

This study suggests that tegafur/uracil plus leucovorin is a feasible adjuvant chemotherapy regimen for patients with stage II colorectal cancer after curative surgical treatment. Prolonged tegafur/uracil plus leucovorin treatment for 12 months showed a trend towards better outcomes in patients with stage II colorectal cancer.

Final results of the real-life observational VICTOR-6 study on metronomic chemotherapy in elderly metastatic breast cancer (MBC) patients

Nowadays, treatment of metastatic breast cancer (MBC) has been enriched with novel therapeutical strategies. Metronomic chemotherapy (mCHT) is a continuous and frequent administration of chemotherapy at a lower dose and so whit less toxicity. Thus, this strategy could be attractive for elderly MBC patients. Aim of this analysis is to provide insights into mCHT's activity in a real-life setting of elderly MBC patients. Data of patients ≥ 75 years old included in VICTOR-6 study were analyzed. VICTOR-6 is a multicentre, Italian, retrospective study, which collected data on mCHT in MBC patients treated between 2011 and 2016. A total of 112 patients were included. At the beginning of mCHT, median age was 81 years (75-98) and in 33% of the patients mCHT was the first line choice. Overall Response Rate (ORR) and Disease Control Rate (DCR) were 27.9% and 79.3%, respectively. Median PFS ranged between 7.6 and 9.1 months, OS between 14.1 and 18.5 months. The most relevant toxicity was the hematological one (24.1%); severe toxicity (grade 3-4) ranged from 0.9% for skin toxicity up to 8% for hematologic one. This is a large study about mCHT in elderly MBC patients, providing insights to be further investigated in this subgroup of frail patients.

Targeting glutaminase is therapeutically effective in ibrutinib-resistant mantle cell lymphoma

Mantle cell lymphoma (MCL) is an incurable B-cell non-Hodgkin lymphoma characterized by frequent relapses. The development of resistance to ibrutinib therapy remains a major challenge in MCL. We previously showed that glutaminolysis is associated with resistance to ibrutinib. In this study, we confirmed that glutaminase (GLS), the first enzyme in glutaminolysis, is overexpressed in ibrutinib-resistant MCL cells, and that its expression correlates well with elevated glutamine dependency and glutaminolysis. Furthermore, we discovered that GLS expression correlates with MYC expression and the functioning of the glutamine transporter ASCT2. Depletion of glutamine or GLS significantly reduced cell growth, while GLS overexpression enhanced glutamine dependency and ibrutinib resistance. Consistent with this, GLS inhibition by its specific inhibitor telaglenastat suppressed MCL cell growth both in vitro and in vivo. Moreover, telaglenastat showed anti-MCL synergy when combined with ibrutinib or venetoclax in vitro, which was confirmed using an MCL patient-derived xenograft model. Our study provides the first evidence that targeting GLS with telaglenastat, alone or in combination with ibrutinib or venetoclax, is a promising strategy to overcome ibrutinib resistance in MCL.

Continuous low-dose cyclophosphamide plus prednisone in the treatment of relapsed and refractory multiple myeloma with severe complications

Background/objective

We retrospectively analyzed the effective and safety of continuous low-dose cyclophosphamide combined with prednisone (CP) in relapsed and refractory multiple myeloma (RRMM) patients with severe complications.

Methods

A total of 130 RRMM patients with severe complications were enrolled in this study, among which 41 patients were further given bortezomib, lenalidomide, thalidomide or ixazomib on the basis of CP regimen (CP+X group). The response to therapy, adverse events (AEs), overall survival (OS) and progression-free survival (PFS) were recorded.

Results

Among the 130 patients, 128 patients received therapeutic response assessment, with a complete remission rate (CRR) and objective response rate (ORR) of 4.7% and 58.6%, respectively. The median OS and PFS time were (38.0 ± 3.6) and (22.9±5.2) months, respectively. The most common AEs were hyperglycemia (7.7%), pneumonia (6.2%) and Cushing's syndrome (5.4%). In addition, we found the pro-BNP/BNP level was obviously decreased while the LVEF (left ventricular ejection fraction) was increased in RRMM patients following CP treatment as compared with those before treatment. Furthermore, CP+X regimen further improved the CRR compared with that before receiving the CP+X regimen (24.4% vs. 2.4%, P=0.007). Also, both the OS and PFS rates were significantly elevated in patients received CP+X regimen following CP regimen as compared with the patients received CP regimen only.

Conclusion

This study demonstrates the metronomic chemotherapy regimen of CP is effective to RRMM patients with severe complications.

Metronomic chemotherapy as a potential partner of immune checkpoint inhibitors for metastatic colorectal cancer treatment

The use of immune checkpoint inhibitors (ICIs) in clinical practice for the treatment of metastatic colorectal cancer (mCRC) is currently limited to patients with deficient mismatch repair (dMMR) or high microsatellite instability (MSI-H), which comprise less than 5% of all mCRC cases. Combining ICIs with anti-angiogenic inhibitors, which modulate the tumor microenvironment, may reinforce and synergize the anti-tumor immune responses of ICIs. In mCRCs, combinations of pembrolizumab and lenvatinib have shown good efficacy in early phase trials. These results suggest the potential utility of immune modulators as partners in combination treatment with ICIs in immunologically cold microsatellite stable, as well as hot dMMR/MSI-H tumors. Unlike conventional pulsatile maximum tolerated dose chemotherapy, low-dose metronomic (LDM) chemotherapy recruits immune cells and normalizes vascular-immune crosstalk, similar to anti-angiogenic drugs. LDM chemotherapy mostly modulates the tumor stroma rather than directly killing tumor cells. Here, we review the mechanism of LDM chemotherapy in terms of immune modulation and its potential as a combination partner with ICIs for the treatment of patients with mCRC tumors, most of which are immunologically cold.

Real-World Experience of Metronomic Chemotherapy in Metastatic Breast Cancer: Results of a Retrospective Unicenter Study

INTRODUCTION

Metronomic chemotherapy (MCT) is increasingly used in oncology due to its favorable therapeutic index. There is still a lack of evidence for MCT in metastatic breast cancer (MBC). In this retrospective unicenter study, we demonstrated real-word data on MCT in MBC.

METHODS

MBC patients who received metronomic oral cyclophosphamide (CTX) (50 mg daily) and methotrexate (MTX) (2.5 mg every other day), CTX and capecitabine (CAPE) (500 mg thrice daily), CTX, or vinorelbine (VRL) (30 mg daily) alone for at least 4 weeks between 2009 and 2021 were included. The primary endpoint was disease control rate (DCR) ≥24 weeks. Secondary endpoints were progression-free survival (PFS) and overall survival (OS). Patient characteristics and therapy response were analyzed using χ2 test. For survival analyses, Kaplan-Meier estimator and log-rank test were used.

RESULTS

Seventy-two patients were identified. Sixty-two patients received CTX/MTX, three CTX/CAPE, two CTX, and five VRL. Median age at diagnosis MBC and at start of MCT was 59.0 years and 64.5 years, respectively. 72.2% tumors were hormone receptor positive and 27.8% were triple-negative. 54.2% patients had more than two different metastases. 80.6% patients showed visceral involvement. 31.9% patients achieved DCR ≥24 weeks. Median PFS was 17.0 weeks (95% CI 14.5-19.5) and median OS was 58.0 weeks (95% CI 29.0-87.0). MCT showed similar DCR ≥24 weeks and clinically meaningful but not statistically significant shorter median PFS compared to prior therapy (31.9% versus 32.8% [p = 0.570] and 17.0 weeks versus 20.0 weeks [p = 0.093], respectively) and statistically significant higher DCR ≥24 weeks and longer median PFS compared to subsequent therapy (31.9% versus 17.4% [p = 0.038] and 17.0 weeks versus 12.0 weeks [p = 0.006], respectively). Three (4.2%) patients terminated MCT because of toxicity.

CONCLUSION

In this real-world retrospective study, MCT was effective and well tolerated and may thus represent a valuable treatment option in selected MBC patients.

Metronomic Chemotherapy: Anti-Tumor Pathways and Combination with Immune Checkpoint Inhibitors

Increasing evidence pinpoints metronomic chemotherapy, a frequent and low dose drug administration with no prolonged drug-free intervals, as a potential tool to fight certain types of cancers. The primary identified targets of metronomic chemotherapy were the tumor endothelial cells involved in angiogenesis. After this, metronomic chemotherapy has been shown to efficiently target the heterogeneous population of tumor cells and, more importantly, elicit the innate and adaptive immune system reverting the "cold" to "hot" tumor immunologic phenotype. Although metronomic chemotherapy is primarily used in the context of a palliative setting, with the development of new immunotherapeutic drugs, a synergistic therapeutic role of the combined metronomic chemotherapy and immune checkpoint inhibitors has emerged at both the preclinical and clinical levels. However, some aspects, such as the dose and the most effective scheduling, still remain unknown and need further investigation. Here, we summarize what is currently known of the underlying anti-tumor effects of the metronomic chemotherapy, the importance of the optimal therapeutic dose and time-exposure, and the potential therapeutic effect of the combined administration of metronomic chemotherapy with checkpoint inhibitors in preclinical and clinical settings.

Nanoformulations-Based Metronomic Chemotherapy: Mechanism, Challenges, Recent Advances, and Future Perspectives

Cancer-related death is a significant health and economic burden worldwide, and some conventional chemotherapy is associated with limited effectiveness in completely curing various cancers, severe adverse effects, and destruction of healthy cells. To overcome the complications associated with conventional treatment, metronomic chemotherapy (MCT) is extensively suggested. In this review, we aim to highlight the importance of MCT over conventional chemotherapeutic approach with emphasis on nanoformulations-based MCT, their mechanism, challenges, recent advances, and future perspectives. Nanoformulations-based MCT revealed remarkable antitumor activity in both preclinical and clinical settings. For example, the metronomic scheduling of oxaliplatin-loaded nanoemulsion and polyethylene glycol-coated stealth nanoparticles incorporating paclitaxel were proven very effective in tumor-bearing mice and rats, respectively. Additionally, several clinical studies have demonstrated the benefit of MCT with acceptable tolerance. Moreover, metronomic might be a promising treatment strategy for improving cancer care in low- and middle-income nations. However, an appropriate alternative to a metronomic regimen for an individual ailment, suitable combinational delivery and scheduling, and predictive biomarkers are certain parts that remain unanswered. Further clinical-based comparative research studies are mandatory to be performed before entailing this treatment modality in clinical practice as alternative maintenance therapy or in place of transferring to therapeutic management.

Immunogenic cell death inducer peptides: A new approach for cancer therapy, current status and future perspectives

Immunogenic Cell Death (ICD) is a type of cell death that kills tumor cells by stimulating the adaptive immune response against other tumor cells. ICD depends on the endoplasmic reticulum (ER) stress and the secretion of Damage-Associated Molecular Patterns (DAMP) by the dying tumor cell. DAMPs recruit innate immune cells such as Dendritic Cells (DC), triggering a cancer-specific immune response such as cytotoxic T lymphocytes (CTLs) to eliminate remaining cancer cells. ICD is accompanied by several hallmarks in dying cells, such as surface translocation of ER chaperones, calreticulin (CALR), and extracellular secretion of DAMPs such as high mobility group protein B1 (HMGB1) and adenosine triphosphate (ATP). Therapeutic peptides can kill bacteria and tumor cells thus affecting the immune system. They have high specificity and affinity for their targets, small size, appropriate cell membrane penetration, short half-life, and simple production processes. Peptides are interesting agents for immunomodulation since they may overcome the limitations of other therapeutics. Thus, the development of peptides affecting the TME and active antitumoral immunity has been actively pursued. On the other hand, several peptides have been recently identified to trigger ICD and anti-cancer responses. In the present review, we review previous studies on peptide-induced ICD, their mechanism, their targets, and markers. They include anti-microbial peptides (AMPs), cationic or mitochondrial targeting, checkpoint inhibitors, antiapoptotic inhibitors, and "don't eat me" inhibitor peptides. Also, peptides will be investigated potentially inducing ICD that is divided into ER stressors, ATPase inhibitors, and anti-microbial peptides.

Metronomic Chemotherapy for Burkitt Lymphoma in a Patient With HIV: Case Report

Burkitt lymphoma (BL) is an aggressive type of non-Hodgkin lymphoma (NHL). With high-dose combination chemotherapy, cure rates are excellent. Treatment for HIV-positive BL is similar to that for HIV-negative BL. Offering long-term intensive chemotherapy is difficult in resource-limited settings. Oral metronomic chemotherapy, though in vogue as a treatment modality, has limited evidence of its efficacy in HIV-positive BL. Here, we present the case of a child who was diagnosed with BL and HIV and administered metronomic chemotherapy, and also review the literature on the role of metronomic chemotherapy in non-Hodgkin lymphoma with and without HIV.

Durable effect of imatinib and metronomic chemotherapy with capecitabine in pancreatic carcinoma

Background

Pancreatic ductal carcinoma (PDC) is a challenging diagnosis with a particularly poor prognosis, even after curative surgery (median survival: <30 months). The prognosis of borderline resectable pancreatic cancer (BR-PDC) is even worse. We describe a patient with BR-PDC who achieved stable disease with metronomic chemotherapy after refusing surgery.

Case presentation

A 75-year-old woman was presented with jaundice and epigastric pain. Imaging confirmed a mass in the pancreatic head encasing the superior mesenteric vein, with obstruction of the pancreatic and bile ducts. After stenting to relieve the obstruction, Fine needle aspiration (FNA) confirmed the diagnosis of PDC. The patient refused surgery and radiation therapy but agreed for chemotherapy. After the second cycle of mFOLFIRINOX - complicated by febrile neutropenia - she refused further IV therapy. Genomic profiling revealed KIT amplification. Therefore, she was started on imatinib with dramatic improvement both clinically and biochemically reflected in carbohydrate antigen 19-9 drop. However, that response was short-lived at 3 months. Therefore, capecitabine was added at a low dose of 1 g bid on an alternate weekly basis. The patient did well and she is currently alive with a stable disease as of 2 years after diagnosis.

Conclusion

Metronomic chemotherapy, especially capecitabine added to the targeted therapy, imatinib, is a potentially useful treatment for PDC where no other options are available, especially those harbouring no mutation in the dominant four genes. Indeed, the absence of mutation with KIT amplification could be a potential marker for improved outcomes with targeted and metronomic therapy, which deserves further evaluation in a clinical trial setting.

Cancer Chemoresistance; Recent Challenges and Future Considerations

Cancer remains one of the serious health hazards and major causes of human mortality across the world. Despite the development of many typical antineoplastic drugs and introduction of novel targeted agents, chemoresistance constitutes a major challenge in the effective therapeutic management of cancer. Drug inactivation, efflux of anticancer agents, modification of target sites, enhanced repair of DNA damage, apoptosis failure and induction of epithelial-mesenchymal transition are the principal mechanisms of cancer chemoresistance. Moreover, epigenetics, cell signaling, tumor heterogeneity, stem cells, microRNAs, endoplasmic reticulum, tumor microenvironment and exosomes have also been implicated in the multifaceted phenomenon of anticancer drug resistance. The tendency of resistance is either intrinsically possessed or subsequently acquired by cancerous cells. From clinical oncology standpoint, therapeutic failure and tumor progression are the most probable consequences of cancer chemoresistance. Combination therapy can help to overcome the issue of drug resistance, and therefore, the development of such treatment regimens is recommended for counteracting the emergence and dissemination of cancer chemoresistance. This chapter outlines the current knowledge on underlying mechanisms, contributory biological factors and likely consequences of cancer chemoresistance. Besides, prognostic biomarkers, diagnostic methods and potential approaches to overcome the emergence of antineoplastic drug resistance have also been described.