Mechanisms of action of topical 5-fluorouracil: review and implications for the treatment of dermatological disorders

Efficacy and safety of 0.5% colchicine cream versus 5% 5-fluorouracil cream in the treatment of cutaneous field cancerization: a randomized clinical trial

BACKGROUND

5-Fluorouracil (5-FU) is a first-line drug to treat cutaneous field cancerization (CFC). There are few clinical trials with topical colchicine (COL).

OBJECTIVE

To evaluate the effectiveness of 0.5% COL cream versus 5% 5-FU cream in the treatment of CFC.

METHOD

This was a randomized, open, self-controlled clinical trial. Forty-five patients (90 forearms), with three to ten actinic keratoses (AK) on each forearm, used 0.5% COL cream 2×/day for seven days on one forearm, and 5% 5-FU cream 2× /day, for 21 days, on the other forearm. The dosages were defined based on previous clinical trials for each drug. Adverse effects were evaluated after 14 days and outcomes after 90 days of inclusion. The primary outcome was complete AK clearance and the secondary outcomes were: partial clearance (≥50%), reduction in AK count, assessment of the Forearm Photoaging Scale (FPS), AK Severity Score (AKSS), and adverse effects.

RESULTS

After 90 days, there was complete clearance of AK in 37% (95% CI 24%-49%) and partial clearance in 85% (95% CI 76%-93%) of the forearms treated with 5-FU,versus 17% (95% CI 7%-27%) and 78% (95% CI 66%-88%) for COL (p > 0.07). There was a percentage reduction of 75% in the AK count of the forearms treated with 5-FU (95% CI 66%-83%) and 64% in those treated with COL (95% CI 55%-72%). Regarding FPS and AKSS, there was improvement in both groups, with no difference regarding FPS (p = 0.654), and 5-FU superiority for AKSS (p = 0.012).

STUDY LIMITATIONS

Single-center study.

CONCLUSIONS

5-FU and COL are effective for treating CFC, with neither showing superiority regarding the reduction in AK counts.

Therapeutic Approaches for Non-Melanoma Skin Cancer: Standard of Care and Emerging Modalities

Skin cancer encompasses a range of cutaneous malignancies, with non-melanoma skin cancers (NMSCs) being the most common neoplasm worldwide. Skin exposure is the leading risk factor for initiating NMSC. Ultraviolet (UV) light induces various genomic aberrations in both tumor-promoting and tumor-suppressing genes in epidermal cells. In conjunction with interactions with a changed stromal microenvironment and local immune suppression, these aberrations contribute to the occurrence and expansion of cancerous lesions. Surgical excision is still the most common treatment for these lesions; however, locally advanced or metastatic disease significantly increases the chances of morbidity or death. In recent years, numerous pharmacological targets were found through extensive research on the pathogenic mechanisms of NMSCs, leading to the development of novel treatments including Hedgehog pathway inhibitors for advanced and metastatic basal cell carcinoma (BCC) and PD-1/PD-L1 inhibitors for locally advanced cutaneous squamous cell carcinoma (cSCC) and Merkel cell carcinoma (MCC). Despite the efficacy of these new drugs, drug resistance and tolerability issues often arise with long-term treatment. Ongoing studies aim to identify alternative strategies with reduced adverse effects and increased tolerability. This review summarizes the current and emerging therapies used to treat NMSC.

Cadherin 17 Nanobody-Mediated Near-Infrared-II Fluorescence Imaging-Guided Surgery and Immunotoxin Delivery for Colorectal Cancer

Surgery and targeted therapy are of equal importance for colorectal cancer (CRC) treatment. However, complete CRC tumor resection remains challenging, and new targeted agents are also needed for efficient CRC treatment. Cadherin 17 (CDH17) is a membrane protein that is highly expressed in CRC and, therefore, is an ideal target for imaging-guided surgery and therapeutics. This study utilizes CDH17 nanobody (E8-Nb) with the near-infrared (NIR) fluorescent dye IRDye800CW to construct a NIR-II fluorescent probe, E8-Nb-IR800CW, and a Pseudomonas exotoxin (PE)-based immunotoxin, E8-Nb-PE38, to evaluate their performance for CRC imaging, imaging-guided precise tumor excision, and antitumor effects. Our results show that E8-Nb-IR800CW efficiently recognizes CDH17 in CRC cells and tumor tissues, produces high-quality NIR-II images for CRC tumors, and enables precise tumor removal guided by NIR-II imaging. Additionally, fluorescent imaging confirms the targeting ability and specificity of the immunotoxin toward CDH17-positive tumors, providing the direct visible evidence for immunotoxin therapy. E8-Nb-PE38 immunotoxin markedly delays the growth of CRC through the induction of apoptosis and immunogenic cell death (ICD) in multiple CRC tumor models. Furthermore, E8-Nb-PE38 combined with 5-FU exerts synergistically antitumor effects and extends survival. This study highlights CDH17 as a promising target for CRC imaging, imaging-guided surgery, and drug delivery. Nanobodies targeting CDH17 hold great potential to construct NIR-II fluorescent probes for surgery navigation, and PE-based toxins fused with CDH17 nanobodies represent a novel therapeutic strategy for CRC treatment. Further investigation is warranted to validate these findings for potential clinical translation.

Pre-treatment with topical 5-fluorouracil increases the efficacy of daylight photodynamic therapy for actinic keratoses - A randomized controlled trial

BACKGROUND

Daylight photodynamic therapy (dPDT) and topical 5-fluorouracil (5-FU) are each effective treatments for thin grade I actinic keratosis (AKs), but less so for thicker grade II-III AKs. Prolonged topical treatment regimens can be associated with severe skin reactions and low compliance. This study compares the efficacy of sequential 4 % 5-FU and dPDT with dPDT monotherapy for multiple actinic keratoses.

METHODS

Sixty patients with a total of 1547 AKs (grade I: 1278; grade II: 246; grade III: 23) were treated in two symmetrical areas (mean size 75 cm2) of the face or scalp, which were randomized to (i) 4% 5-FU creme twice daily for 7 days before a single dPDT procedure and (ii) dPDT monotherapy. Daylight exposure was either outdoor or indoor daylight.

RESULTS

Twelve weeks after treatment 87 % of all AKs cleared after 5-FU+dPDT compared to 74 % after dPDT alone (p<0.0001). For grade II AKs, the lesion response rate increased from 55 % with dPDT monotherapy to 79 % after 5-FU+dPDT (p<0.0056). Moderate/severe erythema was seen in 88 % 5-FU+dPDT areas compared to 41 % of dPDT areas two days after dPDT. Twelve weeks after treatment 75 % of the patients were very satisfied with both treatments.

CONCLUSIONS

Sequential 5-FU and dPDT was more effective than dPDT monotherapy in the treatment of AKs, especially for grade II AKs. Local skin reactions were more pronounced after combination treatment, but no patients discontinued the treatment. The combination of 5-FU and dPDT is an effective treatment of large treatment areas with high compliance and satisfaction.

Bridging Molecular Mechanism and Clinical Practice in Vitiligo Treatment: An Updated Review

BACKGROUND

Treatment of vitiligo seeks to achieve three goals: cessation of disease progression, regeneration of pigmentation, and prevention of recurrence.

SUMMARY

Number of nonsurgical interventions are available that suppress the autoimmune response and regenerate the melanocytes from the reservoir: phototherapy including psoralen and ultraviolet A, narrowband ultraviolet B, and 308-nm excimer and 311-nm Titanium:Sapphire lasers; topical agents including topical calcineurin inhibitors, topical corticosteroids, and topical 5-fluorouracil; and systemic agents including corticosteorids, mycophenolate mofetil, cyclosporine, methotrexate, minocycline, afamelanotide, and antioxidants. In recent years, a great advance has been made in the understanding of pathogenesis of vitiligo, and JAK inhibitors are being investigated as a new treatment. Minimally invasive procedures such as fractional lasers or microneedling can help achieve the optimal treatment outcome when used properly.

KEY MESSAGES

Our review describes various treatment modalities for vitiligo based on their molecular mechanism of action. Bridging the gap between molecular mechanisms and therapeutic options would be a valuable reference for physicians in clinical practice.

Natural Compounds in Non-Melanoma Skin Cancer: Prevention and Treatment

The elevated occurrence of non-melanoma skin cancer (NMSC) and the adverse effects associated with available treatments adversely impact the quality of life in multiple dimensions. In connection with this, there is a necessity for alternative approaches characterized by increased tolerance and lower side effects. Natural compounds could be employed due to their safety profile and effectiveness for inflammatory and neoplastic skin diseases. These anti-cancer drugs are often derived from natural sources such as marine, zoonotic, and botanical origins. Natural compounds should exhibit anti-carcinogenic actions through various pathways, influencing apoptosis potentiation, cell proliferation inhibition, and metastasis suppression. This review provides an overview of natural compounds used in cancer chemotherapies, chemoprevention, and promotion of skin regeneration, including polyphenolic compounds, flavonoids, vitamins, alkaloids, terpenoids, isothiocyanates, cannabinoids, carotenoids, and ceramides.

Melatonin protected against kidney impairment induced by 5-fluorouracil in mice

The utility of 5-fluorouracil (5-FU) as a successful chemotherapeutic drug for several cancers is limited by the induction of kidney injury and dysfunction due to redox imbalance, inflammation, and apoptosis. Meanwhile, melatonin (MLT) is a potent antioxidant and anti-inflammatory natural compound with a wide safety range. The current study aimed to investigate MLT's protective effect against 5-FU-induced kidney impairment. Male mice were given multiple doses of 5-FU at 25 and 100 mg/kg, as well as MLT at 20 mg/kg. MLT treatment alleviated the toxic effect of 5-FU by normalizing blood urea and creatinine levels and preserving the histological structure, indicating MLT's nephroprotective ability. This is accompanied by body weight maintenance, an increase in survival percentage, and preserved hematological parameters in comparison to the 5-FU-treated mice. MLT's renoprotective effect was explained by improvements in C-reactive protein, IL-6, and caspase-3 in kidney tissue, indicating MLT's anti-inflammatory and antiapoptotic ability. Furthermore, MLT inhibited 5-FU-induced lipid peroxidation by maintaining the activity of superoxide dismutase and catalase, as well as glutathione levels in kidney tissue from mice treated with both doses of 5-FU. The current findings show that MLT has a novel protective effect against 5-FU-induced renal injury and renal impairment.

Can immunotherapy reinforce chemotherapy efficacy? a new perspective on colorectal cancer treatment

As one of the main threats to human life (the fourth most dangerous and prevalent cancer), colorectal cancer affects many people yearly, decreases patients' quality of life, and causes irreparable financial and social damages. In addition, this type of cancer can metastasize and involve the liver in advanced stages. However, current treatments can't completely eradicate this disease. Chemotherapy and subsequent surgery can be mentioned among the current main treatments for this disease. Chemotherapy has many side effects, and regarding the treatment of this type of tumor, chemotherapy can lead to liver damage, such as steatohepatitis, steatosis, and sinus damage. These damages can eventually lead to liver failure and loss of its functions. Therefore, it seems that other treatments can be used in addition to chemotherapy to increase its efficiency and reduce its side effects. Biological therapies and immunotherapy are one of the leading suggestions for combined treatment. Antibodies (immune checkpoint blockers) and cell therapy (DC and CAR-T cells) are among the immune system-based treatments used to treat tumors. Immunotherapy targets various aspects of the tumor that may lead to 1) the recruitment of immune cells, 2) increasing the immunogenicity of tumor cells, and 3) leading to the elimination of inhibitory mechanisms established by the tumor. Therefore, immunotherapy can be used as a complementary treatment along with chemotherapy. This review will discuss different chemotherapy and immunotherapy methods for colorectal cancer. Then we will talk about the studies that have dealt with combined treatment.

Antibacterial properties of phosphine gold(I) complexes with 5-fluorouracil

New gold(I) complexes with coordination to 5-fluorouracil (5-FU), an anticancer drug with antibacterial properties, have been synthesised and characterised, and are the first reported examples of 5-FU-Au compounds. These new complexes show high solution stability, even in the presence of a cysteine derivative, and so were evaluated as antibacterial compounds against model Gram-positive and Gram-negative bacteria. All the complexes show excellent antibacterial activity against Gram-positive B. subtilis, most of them improving the activity of 5-FU alone. Furthermore, these new complexes are also active against Gram-negative E. coli, where [Au(5-FU)(PTA)], the complex with the smallest phosphane, is the most bactericidal, 32 times more active than 5-FU on its own.

Pharmacological Agents Used in the Prevention and Treatment of Actinic Keratosis: A Review

Actinic keratosis (AK) is among the most commonly diagnosed skin diseases with potentially life-threatening repercussions if left untreated. Usage of pharmacologic agents represents one of many therapeutic strategies that can be used to help manage these lesions. Ongoing research into these compounds continues to change our clinical understanding as to which agents most benefit particular patient populations. Indeed, factors such as past personal medical history, lesion location and tolerability of therapy only represent a few considerations that clinicians must account for when prescribing appropriate treatment. This review focuses on specific drugs used in either the prevention or treatment of AKs. Nicotinamide, acitretin and topical 5-fluorouracil (5-FU) continue to be used with fidelity in the chemoprevention of actinic keratosis, although some uncertainty persists in regard to which agents should be used in immunocompetent vs. immunodeficient/immunosuppressed patients. Topical 5-FU, including combination formulations with either calcipotriol or salicylic acid, as well as imiquimod, diclofenac and photodynamic light therapy are all accepted treatment strategies employed to target and eliminate AKs. Five percent of 5-FU is regarded as the most effective therapy in the condition, although the literature has conflictingly shown that lower concentrations of the drug might also be as effective. Topical diclofenac (3%) appears to be less efficacious than 5% 5-FU, 3.75-5% imiquimod and photodynamic light therapy despite its favorable side effect profile. Finally, traditional photodynamic light therapy, while painful, appears to be of higher efficacy in comparison to its more tolerable counterpart, daylight phototherapy.

Worsening Rash in a Patient With Metastatic Breast Cancer

A 56-year-old woman with metastatic hormone receptor–positive, ERBB2-negative breast cancer presents with pruritic, erythematous, scaly macules and papules on her forearms, faces, chest, and upper back. What is your diagnosis?

When Two Maladies Meet: Disease Burden and Pathophysiology of Stroke in Cancer

Stroke and cancer are disabling diseases with an enormous global burden, disproportionately affecting vulnerable populations and low- and middle-income countries. Both these diseases share common risk factors, which warrant concerted attention toward reshaping population health approaches and the conducting of fundamental studies. In this article, an overview of epidemiological trends in the prevalence and burden of cancer and stroke, underlying biological mechanisms and clinical risk factors, and various tools available for risk prediction and prognosis are provided. Finally, future recommendations for research and existing gaps in our understanding of pathophysiology. Further research must investigate the causes that predispose patients to an increased risk of stroke and/or cancer, as well as biomarkers that can be used to predict growing morbidity and mortality.

Comparative efficacy of intralesional 5 Flurouracil and intralesional Triamcinolone acetonide in localized plaque psoriasis

BACKGROUND

Psoriasis is a papulosquamous disorder that causes significant social and psychological trauma to the patient. It is characterized by the presence of erythematous, indurated plaques covered with silvery-white scales. Despite the availability of several systemic agents that have been approved for the treatment of psoriasis, usually there are some residual lesions and there is a need to treat them for cosmetic reasons or symptomatic control.

AIMS

1. Treatment of resistant localized psoriatic plaques or residuals after systemic treatment. 2. Recently, some intralesional agents have been used successfully for the treatment of psoriatic plaques as 5-FU, methotrexate, and botulinum toxin type-A, and nearly for 4 decades, no study focused on the effect of intralesional corticosteroids in the treatment of these psoriatic plaques. We decided to highlight their role and compare intralesional Triamcinolone to intralesional 5-FU regarding efficacy and safety in the treatment of plaque psoriasis.

METHODS

This study included 24 patients with localized plaque psoriasis. Each patient was treated by split-body therapy where one psoriatic plaque was treated with intralesional 5FU and another plaque with intralesional TAC. A total of three injections were given at two- week intervals and follow up was regularly every 2 weeks up to 12 weeks.

RESULTS

There was a statistically significant difference between both groups (p = 0.008) as the response rate on 5-FU side was 12.5% with no response, 29.2% with a moderate response, 41.7% with an excellent response, and 16.7% with a complete clearance, while on the TAC side it was16.7% with a moderate response, 20.8% with an excellent response and 62.5% with a complete clearance. Hyperpigmentation was the most irritating side effect of 5-FU that occurred. Pain, during and after injection, was greater in 5-FU group. Hypopigmentation and atrophy only occurred in TAC group in some patients but it seems to be reversible and not disfiguring.

CONCLUSION

1-Intralesional TAC injection may have more efficacy and less side effects than 5-FU injection in the treatment of localized plaque psoriasis. Hyperpigmentation and pain were the most irritating side effects of 5-FU 2-Intralesional TAC can be effective in the treatment of localized psoriatic plaques with minimal side effects, especially in patients not suitable for systemic agents.

A Conservative Combined Laser Cryoimmunotherapy Treatment vs. Surgical Excision for Basal Cell Carcinoma

Surgical excision is the standard treatment for basal cell carcinoma (BCC), but it can be challenging in elderly patients and patients with comorbidities. The non-surgical guidelines procedures are usually regarded as monotherapy options. This quasi-experimental, non-randomized, comparative effectiveness study aims to evaluate the efficacy of a combined, conservative, non-surgical BCC treatment, and compare it to standard surgical excision. Patients with primary, non-ulcerated, histopathologically confirmed BCCs were divided into a conservative treatment (129 patients) and a standard surgery subgroup (50 patients). The conservative treatment consisted of ablative CO2 laser, cryosurgery, topical occlusive 5-fluorouracil, and imiquimod. The follow-up examinations were performed 3 months after remission, then every 3 to 6 months, and were extended with telephone follow-ups. Cosmetic-self assessment was recorded during a telephone follow-up. Subjects from the conservative subgroup presented a clearance rate of 99.11%, and a recurrence rate of 0.98%. No recurrences were recorded in the surgical group, nor during the telephone follow-up. There were no differences regarding adverse events (p > 0.05). A superior self-assessment cosmetic outcome was obtained using the conservative method (p < 0.001). This conservative treatment is suitable for elders and patients with comorbidities, is not inferior to surgery in terms of clearance, relapses, or local adverse events, and displays superior cosmetic outcomes.

An updated review on properties, nanodelivery systems, and analytical methods for the determination of 5-fluorouracil in pharmaceutical and biological samples

Abstract:

5-Fluorouracil (5-FU) is an antimetabolite drug used for over 70 years as first-line chemotherapy to treat various types of cancer, such as head, neck, breast and colorectal cancer. 5-FU acts mainly by inhibiting thymidylate synthase, thereby interfering with deoxyribonucleic acid (DNA) replication or by 5-FU incorporating into DNA, causing damage to the sequence of nucleotides. Being analogous to uracil, 5-FU enters cells using the same transport mechanism, where a is converted into active metabolites such as fluorouridine triphosphate (FUTP), fluorodeoxyuridine monophosphate (FdUMP), and fluorodeoxyuridine triphosphate (FdUTP). Currently, there are several nanodelivery systems being developed and evaluated at the preclinical level to overcome existing limitations to 5-FU chemotherapy, including liposomes, polymeric nanoparticles, polymeric micelles, nanoemulsions, mesoporous silica nanoparticles, and solid lipid nanoparticles. Therefore, it is essential to choose and develop suitable analytical methods for the quantification of 5-FU and its metabolites (5-fluorouridine and 5-fluoro-2-deoxyuridine) in pharmaceutical and biological samples. Among the analytical techniques, chromatographic methods are commonly the most used for the quantification of 5-FU from different matrices. However, other analytical methods have also been developed for the determination of 5-FU, such as electrochemical methods, a sensitive, selective, and precise technique, in addition to having a reduced cost. Here, we first review the physicochemical properties, mechanism of action, and advances in 5-FU nanodelivery systems. Next, we summarize the current progress of other chromatographic methods described to determine 5-FU. Lastly, we discuss the advantages of electrochemical methods for the identification and quantification of 5-FU and its metabolites in pharmaceutical and biological samples.

Determination of in vivo virtue of dermal targeted combinatorial lipid nanocolloidal based formulation of 5-fluorouracil and resveratrol against skin cancer

The current study has been designed to appraise the efficacy of developed combinatorial lipid-nanosystem-based gel (linogel) of 5-fluorouracil and resveratrol for skin cancer treatment. Initially, linogel was prepared and characterized for different parameters, namely pH, texture, drug content uniformity, occlusiveness, etc. Then in vivo efficacy studies (tumor number, area, and volume, histopathology, ultrastructural and immunohistochemical analysis) of linogel were determined over-developed skin tumors. Developed linogel possessed significantly (p < 0.05) better texture and occlusiveness than conventional gel formulation. Decreased tumor number, area, and volume showed significant results (p < 0.05) in favor of linogel. Histopathological and ultrastructural analysis confirmed superior efficacy of linogel in terms of marked improvement in the nucleus and subcellular structures in photomicrographs. The antioxidants and anti-inflammatory analysis findings showed a significantly (p < 0.05) potent effectiveness of linogel. The apoptotic and anti-proliferation activity of linogel was confirmed by analysis of caspase-3 and ki-67, which showed significant (p < 0.05) elevation in the level of cleaved caspase-3 and reduction in the level of ki-67 than untreated and conventional gel formulation treated tumors, indicating antitumor effect due to cancerous cell death. Thus, developed linogel fulfilled all the criteria of dermal application and exhibited efficacious therapeutic results, which could be a beneficial therapeutic approach against skin cancer.

Local Chemotherapy as an Adjuvant Treatment in Unresectable Squamous Cell Carcinoma: What Do We Know So Far?

Background: Squamous cell carcinoma (SCC) is one of the most common cancers involving skin and oral mucosa. Although this condition's gold-standard treatment is the surgical removal of the lesions, the physician must propose alternative treatments in some cases due to the patient's ineligibility for surgery. Among the available alternative therapies, local chemotherapy may represent an initial treatment in combination with radiotherapy or systemic chemotherapy due to the low frequency of side-effects and the lack of necessity for expensive devices. Methods: In this paper, we review all available literature in various databases (PubMed, Scopus-Embase, Web of Science), proposing local chemotherapy as a treatment for cutaneous and oral SCC. Exclusion criteria included ocular lesions (where topical treatments are common), non-English language, and non-human studies. Results: We included 14 studies in this review. The majority were case reports and case series describing the treatment of non-resectable localized SCC with either imiquimod or 5-fluorouracil. We also analyzed small studies proposing combination treatments. Almost all studies reported an excellent clinical outcome, with a low risk of relapses in time. Conclusions: Resection of the lesion remains the gold-standard treatment for SCC. When this approach is not feasible, local chemotherapy may represent a treatment alternative, and it may also be associated with radiotherapy or systemic chemotherapy.

Oncogenic viruses and chemoresistance: What do we know?

Chemoresistance is often referred to as a major leading reason for cancer therapy failure, causing cancer relapse and further metastasis. As a result, an urgent need has been raised to reach a full comprehension of chemoresistance-associated molecular pathways, thereby designing new therapy methods. Many of metastatic tumor masses are found to be related with a viral cause. Although combined therapy is perceived as the model role therapy in such cases, chemoresistant features, which is more common in viral carcinogenesis, often get into way of this kind of therapy, minimizing the chance of survival. Some investigations indicate that the infecting virus dominates other leading factors, i.e., genetic alternations and tumor microenvironment, in development of cancer cell chemoresistance. Herein, we have gathered the available evidence on the mechanisms under which oncogenic viruses cause drug-resistance in chemotherapy.

Inhibition of lncRNA-NEAT1 sensitizes 5-Fu resistant cervical cancer cells through de-repressing the microRNA-34a/LDHA axis

Cervical cancer is one of the most diagnosed malignancies among females. The 5-fluorouracil (5-Fu) is a widely used chemotherapeutic agent against diverse cancers. Despite the initially encouraging progresses, a fraction of cervical cancer patients developed 5-Fu resistance. We detected that nuclear-rich transcripts 1 (NEAT1) was significantly up-regulated in cervical cancer tissues and cell lines. Moreover, NEAT1 was positively associated with 5-Fu resistance. Furthermore, expression of NEAT1 was significantly up-regulated in 5-Fu resistant CaSki cervical cancer cells. Knocking down NEAT1 by shRNA dramatically promoted the sensitivity of 5-Fu resistant CaSki cells. We observed a negative correlation between long noncoding RNA (lncRNA)-NEAT1 and miR-34a in cervical cancer patient tissues. Overexpression of miR-34a significantly sensitized 5-Fu resistant cells. Bioinformatics analysis uncovered that NEAT1 functions as a competitive endogenous RNA (ceRNA) of miR-34a in cervical cancer cells via sponging it at multiple sites to suppress expression of miR-34a. This negative association between NEAT1 and miR-34a was further verified in cervical cancer tissues. We found the 5-Fu resistant cells displayed significantly increased glycolysis rate. Overexpression of miR-34a suppressed cellular glycolysis rate and sensitized 5-Fu resistant cells through direct targeting the 3′-untranslated region (UTR) of LDHA, a glycolysis key enzyme. Importantly, knocking down NEAT1 successfully down-regulated LDHA expressions and glycolysis rate of cervical cancer cells by up-regulating miR-34a, a process could be further rescued by miR-34a inhibition. Finally, we demonstrated inhibition of NEAT1 significantly sensitized cervical cancer cells to 5-Fu through the miR-34a/LDHA pathway. In summary, the present study suggests a new molecular mechanism for the NEAT1-mediated 5-Fu resistance via the miR-34a/LDHA-glycolysis axis.

Penile sparing therapy for penile cancer

Penile cancer is a rare malignancy with a reported incidence of 0.66–1.44 per 100,000 men, and a reported mortality of 0.15–0.37 per 10,000 men. Expert clinical examination and histological diagnosis from biopsy is required to determine the extent and invasion of disease, which is paramount in planning of appropriate treatment. Management of loco-regional penile cancer can be divided into management of primary tumour and management of regional lymph nodes. This review article will focus on the management of the primary penile tumour with particular focus on penile sparing therapies. The aim of primary penile tumour management is to completely remove the tumour whilst preserving as much organ function as possible. Preservation of the penis is important as it allows patients to maintain urinary and sexual function, as well as quality of life. With the majority of penile cancer confined to the glans and foreskin, most penile cancers can be managed with organ-preserving therapy. A wide variety of treatment options are available, and this review aims to describe each of the options including the reported oncological and functional outcome for the different therapies for penile cancer.

In silico design and evaluation of novel 5-fluorouracil analogues as potential anticancer agents

5-fluorouracil (5-FU) has been shown to have suffered from resistance which demands a solution entailing the development of 5-FU analogues. Our study aims to design a number of analogues of 5-FU and evaluate their effectiveness against thymidylate synthase (TS) in silico compared to parent 5-FU with an effort to obtain better hit(s). All the molecules were optimized by molecular mechanics method utilizing MM2 forcefield parameters. Molecular docking of these molecules against TS was performed to catch on the binding strength of these molecules, determination of binding energy & interaction types of each ligand-target complex as well as subsequent analysis. PRA10 showed highest binding affinity (-9.1 Kcal/mol). Although binding energy of PRA6 & PRA14 are slightly lower than PRA10, they can be of special interest since they interact with crucial amino acids for binding and exhibit substantial non-bonded interactions. Residue analysis revealed that Arg50A, Arg175B, Arg215A, Ser216A, Arg176B and Asn226A of TS active site were crucial for binding/interaction. The best scored drug candidates demonstrated considerable pharmacokinetic as well as druglike properties. The present study also revealed that PRA6, PRA10 and PRA14 can be potential anticancer drugs for further development.

Ancistrosecolines A-F, Unprecedented seco-Naphthylisoquinoline Alkaloids from the Roots of Ancistrocladus abbreviatus, with Apoptosis-Inducing Potential against HeLa Cancer Cells

Ancistrosecolines A-F (8-13) are the first seco-type naphthylisoquinoline alkaloids discovered in Nature. In all these novel compounds, the tetrahydroisoquinoline ring is cleaved, with loss of C-1. They were isolated from the root bark of Ancistrocladus abbreviatus (Ancistrocladaceae), along with 1-nor-8-O-demethylancistrobrevine H (14), which is the first naturally occurring naphthylisoquinoline lacking the otherwise generally present methyl group at C-1. The stereostructures of the new alkaloids were established by HRESIMS, 1D and 2D NMR, oxidative degradation, and experimental and quantum-chemical ECD investigations. Ancistrosecolines A-F (8-13) and 1-nor-8-O-demethylancistrobrevine H (14) are typical Ancistrocladaceae-type metabolites, i.e., oxygenated at C-6 and S-configured at C-3, belonging to the subclasses of 7,1'- and 7,8'-coupled alkaloids. The biaryl linkages of 8-14 are rotationally hindered due to bulky ortho-substituents next to the axes. Owing to the constitutionally unsymmetric substitution patterns on each side of the axis, this C-C single bond represents an element of chirality in 1-nor-8-O-demethylancistrobrevine H (14) and in ancistrosecolines A-D (8-11). In ancistrosecolines E (12) and F (13), however, the likewise rotationally hindered biaryl axes do not constitute chiral elements, due to a symmetric substitution pattern, with its identical two methoxy functions at C-6 and C-8 in the phenyl subunit. And these two methoxy groups are, for the first time, not constitutionally heterotopic, but diastereotopic to each other. Ancistrosecoline D (11) exhibits strong cytotoxicity against HeLa cervical cancer cells. As visualized by Hoechst nuclei staining and by real-time imaging experiments, 11 induced massive nuclei fragmentation in HeLa cells, leading to apoptotic cell death.

Modulating the solubility and pharmacokinetic properties of 5-fluorouracil via cocrystallization

The solubility and pharmacokinetic properties of 5-fluorouracil were modified by cocrystallization with dihydroxybenzoic acids.

Inhibiting the HPV16 oncogene-mediated glycolysis sensitizes human cervical carcinoma cells to 5-fluorouracil

BACKGROUND

Human papillomavirus (HPV), the major cause of cervical cancer worldwide, is associated with infection of HPV (Oncogenic HPV). Cancer patients who develop drug resistance are resulted in failure of chemotherapy.

OBJECTIVE

We investigated the mechanisms for the HPV E6/E7 oncoprotein-mediated 5-fluorouracil (5-Fu) sensitivity.

METHODS

HPV-16 E6/E7 was transfected into human cervical cancer cell lines. Glycolysis rate was assessed. Xenograft model was established to examine the in vivo therapeutic effects of E6/E7 inhibition and 5-Fu treatments.

RESULTS

The HPV-16 E6/E7 oncoprotein induces 5-Fu resistance in cervical cancer cells. Overexpression of E6/E7 renders CaSki and SiHa cells resistant to 5-Fu treatments. We found E6/E7 expressions were significantly upregulated in 5-Fu-resistant cells compared with parental cells. Moreover, the cellular glycolysis rate was significantly increased in 5-Fu-resistant cells. The glucose uptake, lactate production, and expressions of glycolysis enzymes were upregulated in 5-Fu-resistant cells. We report the E6/E7-mediated 5-Fu resistance was through upregulation of glycolysis pathway. Importantly, inhibition of E6/E7 by shRNA effectively decreased cellular glycolysis and overcame 5-Fu resistance using in vitro and in vivo xenograft model.

CONCLUSION

Our study contributed to understanding the molecular mechanisms for HPV E6/E7-mediated 5-Fu resistance and development of new therapeutic strategies against cervical cancer.

A patient with squamous cell carcinoma in-situ successfully treated with intralesional 5-Fluorouracil and topical trichloroacetic acid

Background: The current gold standard and the first line of treatment for non-melanoma skin cancer is surgical excision. Nevertheless, some patients are not good candidates for surgery when wound healing may be impaired.Methods: A 96-year-old male presented with 1.2 cm by 1.5 cm tumoral lesion with an ill-infiltrated border and central ulceration located on the mid right lower leg. Biopsy confirmed the diagnosis of squamous cell carcinoma (SCC) in situ. The primary lesion was treated centrally to peripherally with multiple intralesional injections of 1.5 mL 5-Fluorouracil (5-FU) (50 mg/mL). The lesion was also treated with a single layer application of 80% Trichloroacetic acid (topical solution). One additional and final treatment of only 80% TCA was performed after three weeks.Results: There was a complete regression of the SCC three weeks after the second treatment.Conclusions: We demonstrate a case of SCC successfully treated with intralesional 5-FU and topical Trichloroacetic acid. Additionally, the SCC in situ was successfully cleared in two treatment sessions with the lowest cumulative dose of 5-FU reported. Intralesional injections of 5-FU and subsequent topical Trichloroacetic acid may be an effective option for patients with SCC who are not eligible for cutaneous surgery.

Mediators of Inflammation in Topical Therapy of Skin Cancers

Taking into consideration that the immune system plays a very important role in the development of melanoma and non-melanoma skin cancers, which have a high prevalence in immunosuppressed patients and after prolonged ultraviolet radiation, the interest in developing novel therapies, in particular targeting the inflammation in cancer, has increased in the past years. The latest data suggest that therapies such as imiquimod (IMQ), ingenol mebutate (IM), 5-fluorouracil (5-FU), retinoids, and nonsteroidal anti-inflammatory drugs (NSAIDs) have been used with success in the topical treatment of some cancers. Herein, we review the topical treatment targeting the inflammation in skin cancer and the mechanisms involved in these processes. Currently, various associations have shown a superior success rate than monotherapy, such as systemic acitretin and topical IMQ, topical 5-FU with tretinoin cream, or IMQ with checkpoint inhibitor cytotoxic T lymphocyte antigen 4. Novel therapies targeting Toll-like receptor-7 (TLR-7) with higher selectivity than IMQ are also of great interest.

Topical 5-fluorouracil in dermatologic disease

BACKGROUND

5-fluorouracil (5-FU) has proven to be an effective therapy in the treatment of a variety of dermatologic conditions. Approved by the United States Food and Drug Administration for the treatment of actinic keratoses and superficial basal cell carcinoma, topical 5-FU has also demonstrated efficacy in the treatment of a variety of other dermatologic diseases.

METHODS

A search of the MEDLINE standard computer database, MEDLINE advanced database, and EMBASE database was conducted.

RESULTS

Thirty-four articles met criteria for inclusion in this review. These articles represented 16 randomized controlled trials and 18 case series. Each article was reviewed and summarized.

CONCLUSIONS

Topical 5-FU is used in a variety of dermatologic disease processes with a wide range of efficacy and levels of evidence. Based on extent and level of evidence, our disease-specific systematic review found that the evidence is strongest for topical 5-FU use in the treatment of actinic keratosis, squamous cell carcinoma, and basal cell carcinoma. This review serves as a comprehensive summary of topical 5-FU use in dermatology.

Effects of cisplatin-5-fluorouracil combination therapy on oxidative stress, DNA damage, mitochondrial apoptosis, and death receptor signalling in retinal pigment epithelium cells

AIM

Combination therapies of cisplatin with 5-FU (PF) are an effective solution and have been widely used for the treatment of various categories of cancer including anal, gastrointestinal, and oral cancer, as well as head and neck tumors. The effects of combined PF treatment on vital intracellular signalling pathways in nontargeted cells remain unclear. The aim of this study is to explain the possible mechanisms by which combined PF treatment results in retinal toxicity and to investigate the effects of PF on important vital signalling pathways in ARPE 19 retinal pigmented epithelial cells.

MATERIALS AND METHODS

We analysed the cellular and molecular effects of PF on cell viability, oxidative stress, gene repair response, and induction of apoptosis in ARPE 19 cells using molecular probe fluorescent staining, cell cytometer, RAPD, qRT-PCR, and western blot assays.

RESULTS

We determined that PF causes excessive generation of reactive oxygen species (ROS) and prevents ROS scavenging by suppressing antioxidant systems. We found induction of DNA damage, particularly mismatch and double strand break repair, in ARPE 19 cells treated with PF. In this study, PF also induced both the intrinsic apoptosis pathway and death receptor signalling in ARPE 19 cells.

CONCLUSIONS

Our data proved that PF causes cytotoxicity and genotoxicity, at both the cellular and molecular levels, in ARPE 19 cells following particularly prolonged treatment (48 h). Additionally, our results suggest key molecular signals for prevention strategies that can be developed to reduce the severe side effects of PF chemotherapy.

Effect of Topical Fluorouracil Cream on Photodamage: Secondary Analysis of a Randomized Clinical Trial

Importance

Photoaging, which is premature skin aging caused by long-term UV exposure, is of aesthetic concern to many patients.

Objective

To investigate the effect of topical fluorouracil, 5%, cream on photoaging using validated photonumeric scales.

Design, Setting, and Participants

The Veterans Affairs Keratinocyte Carcinoma Chemoprevention Trial was a randomized clinical trial of 932 US veterans with a recent history of 2 or more keratinocyte carcinomas performed from September 30, 2011, through June 30, 2014, to assess the chemopreventive effects of a standard course of topical fluorouracil. Photographs were taken at baseline and at numerous time points for up to 4 years. In our secondary analysis, 2 independent dermatologists graded these photographs using 4 validated photonumeric scales. A total of 3042 photographs from 281 participants randomized to apply topical fluorouracil or placebo were evaluated at baseline, 6 months, 12 months, and 18 months using 4 photonumeric scales (Griffiths scale, Allergan forehead lines scale, melomental folds scale, and crow's feet scale). Data analysis was performed from November 1, 2016, to January 1, 2017.

Interventions

Participants were randomized to apply topical fluorouracil, 5%, cream or a vehicle control cream to the face and ears twice daily for 2 to 4 weeks for a total of 28 to 56 doses.

Main Outcomes and Measures

Effect of a standard course of fluorouracil on the extent of photodamage as measured using 4 photonumeric scales.

Results

The study population was predominantly male (274 [97.5%]) and white (281 [100%]), with a mean (SD) age of 71.5 (0.57) years. No statistically significant changes were found in photodamage between baseline and 6 months (Griffiths scale: χ2 = 0.01, P = .93; Allergan forehead lines scale: χ2 = 0.18, P = .67; melomental fold scale: χ2 = 0.03, P = .87; crow's feet scale: χ2 = 2.41, P = .12), 12 months (Griffiths scale: χ2 = 1.39, P = .24; Allergan forehead lines scale: χ2 = 0.64, P = .43; melomental fold scale: χ2 = 0.12, P = .73; crow's feet scale: χ2 = 1.07, P = .30), and 18 months (Griffiths scale: χ2 = 3.11, P = .08; Allergan forehead lines scale: χ2 = 0.89, P = .34; melomental fold scale: χ2 = 1.64, P = .20; crow's feet scale: χ2 = 0.46, P = .50).

Conclusions and Relevance

This study did not demonstrate improvement in photoaging with a standard course of topical fluorouracil, 5%, cream, a finding that may be attributable to a true lack of effect in photodamage or limitations of the photonumeric scales in capturing the effect. The development of photonumeric scales that include manifestations of photoaging other than rhytids, such as lentigines, hyperpigmentation, and telangiectasias, should be considered.

Trial Registration

clinicaltrials.gov Identifier: NCT00847912.

Gold nanoparticles capped with benzalkonium chloride and poly (ethylene imine) for enhanced loading and skin permeability of 5-fluorouracil

OBJECTIVE

To enhance 5-fluorouracil (5-FU) permeability through the skin by loading onto gold nanoparticles (GNPs) capped with two cationic ligands, benzalkonium chloride (BC) or poly (ethylene imine) (PEI). Whereas 5-FU has excellent efficacy against many cancers, its poor permeability through biological membranes and several adverse effects limit its clinical benefits. BC and PEI were selected to stabilize GNPs and to load 5-FU through ionic interactions.

METHODS

5-FU/BC-GNPs and 5-FU/PEI-GNPs were prepared at different 5-FU/ligand molar ratios and different pH values and were evaluated using different techniques. GNPs stability was tested as a function of salt concentration and storage time. 5-FU release from BC- and PEI-GNPs was evaluated as a function of solution pH. Ex vivo permeability studies of different 5-FU preparations were carried out using mice skin.

RESULTS

5-FU-loaded GNPs size and surface charge were dependent on the 5-FU/ligand molar ratios. 5-FU entrapment efficiency and loading capacity were dependent on the used ligand, 5-FU/ligand molar ratio and solution pH. Maximum drug entrapment efficiency of 59.0 ± 1.7% and 46.0 ± 1.1% were obtained for 5-FU/BC-GNPs and 5-FU/PEI-GNPs, respectively. 5-FU-loaded GNPs had good stability against salinity and after storage for 4 months at room temperature and at 4 °C. In vitro 5-FU release was pH- and ligand-dependent where slower release was observed at higher pH and for 5-FU/BC-GNPs. 5-FU permeability through mice skin was significantly higher for drug-loaded GNPs compared with drug-ligand complex or drug aqueous solution.

CONCLUSION

Based on these results, BC- and PEI-GNPs might find applications as effective topical delivery systems of 5-FU.

Topical therapies for the treatment of anal high-grade squamous intraepithelial lesions

Anal cancer may be prevented by treating anal high-grade squamous intraepithelial lesions (HSIL). Ablative therapies are the most commonly used treatments, but they may not be appropriate for all patients including those with extensive HSIL or bleeding diastheses. Researchers have studied topical therapies for human papillomavirus related lesions including anal HSIL. These therapies include patient-applied 5-fluorouracil, imiquimod and cidofovir, and provider-applied trichloroacetic acid. This review will discuss literature supporting efficacy of these products, which is based mainly on case series with few controlled trials having been conducted. Side effects are common with patient-applied topical therapy often requiring dose reduction and medication to treat pain. However, treatment discontinuations are infrequent. This review will also discuss some approaches to the use of these products in clinical practice.

Sequential treatment of multiple actinic keratoses with solaraze and actikerall

Interest is increasing in the use of sequential or combined therapeutic modalities for spot or area treatment of actinic keratoses (AKs) to achieve complete sustained remission. For multiple lesions in a contained area, topical treatment offers less discomfort, better cosmesis and greater patient convenience than destructive/ablative techniques. Twelve patients with multiple grade I and II AK lesions of the scalp (cases 1–10) or the dorsum of the hand (cases 11 and 12), most with a history of recurrence, were treated with Solaraze gel (3% diclofenac sodium in 2.5% hyaluronic acid) twice daily for 12 weeks, followed by a 2-week treatment-free interval, then Actikerall cutaneous solution (5-fluorouracil 5 mg/g and salicylic acid 100 mg/g) once daily for up to 6 weeks as required. Sequential treatment provided complete (clinical and histological) clearance in 8/10 male patients. Two patients with numerous lesions had partial clearance (significant improvement) and the remaining few lesions were treated with erbium laser. Both female patients achieved complete clinical clearance with sequential treatment. Solaraze/Actikerall were well tolerated. A case of contact dermatitis with Solaraze resolved after discontinuation and the patient progressed to treatment with Actikerall. Local application site reactions resolved upon treatment completion. Topical lesion-directed sequential treatment with Solaraze/Actikerall is a rational approach to treat patients with multiple AKs. Sequential treatment produces excellent clearance rates which are accompanied by relevant improvement in patients’ quality of life.

The effect of microneedles on the skin permeability and antitumor activity of topical 5-fluorouracil

Topical 5-fluorouracil (5-FU) is approved for the treatment of superficial basal cell carcinoma and actinic keratosis. However, 5-FU suffers from poor skin permeation. Microneedles have been successfully applied to improve the skin permeability of small and large molecules, and even nanoparticles, by creating micron-sized pores in the stratum corneum layer of the skin. In this report, the feasibility of using microneedles to increase the skin permeability of 5-FU was tested. Using full thickness mouse skin mounted on Franz diffusion apparatus, it was shown that the flux of 5-FU through the skin was increased by up to 4.5-fold when the skin was pretreated with microneedles (500 μm in length, 50 μm in base diameter). In a mouse model with B16-F10 mouse melanoma cells implanted in the subcutaneous space, the antitumor activity of a commercially available 5-FU topical cream (5%) was significantly enhanced when the cream was applied on a skin area that was pretreated with microneedles, as compared to when the cream was simply applied on a skin area, underneath which the tumor cells were implanted, and without pretreatment of the skin with microneedles. Fluorouracil is not approved for melanoma therapy, but the clinical efficacy of topical 5-FU against tumors such as basal cell carcinoma may be improved by integrating microneedle technology into the therapy.

Optimal treatment of actinic keratoses

The most compelling reason and primary goal of treating actinic keratoses is to prevent malignant transformation into invasive squamous cell carcinoma, and although there are well established guidelines outlining treatment modalities and regimens for squamous cell carcinoma, the more commonly encountered precancerous actinic lesions have no such standard. Many options are available with variable success and patient compliance rates. Prevention of these lesions is key, with sun protection being a must in treating aging patients with sun damage as it is never too late to begin protecting the skin.