Effects of 5-fluorouracil on proliferating fibroblasts in vivo

Folic-Acid-Conjugated Thermoresponsive Polymeric Particles for Targeted Delivery of 5-Fluorouracil to CRC Cells

Colorectal cancer is the fourth most common cancer worldwide and the third most frequently diagnosed form of cancer associated with high mortality rates. Recently, targeted drug delivery systems have been under increasing attention owing to advantages such as high therapeutic effectiveness with a significant depletion in adverse events. In this report, we describe the biocompatible and thermoresponsive FA-conjugated PHEA-b-PNIPAAm copolymers as nanocarriers for the delivery of 5-FU. The block copolymers were obtained using RAFT (Reversible Addition-Fragmentation chain Transfer) polymerization and were characterized by methods such as SEC (Size Exclusion Chromatography), NMR (Nuclear Magnetic Resonance), UV-Vis (Ultraviolet-Visible), FT-IR (Fourier Transform Infrared) spectroscopy, and TGA (Thermogravimetric Analysis). Nanoparticles were formed from polymers with and without the drug-5-fluorouracil, which was confirmed using DLS (Dynamic Light Scattering), zeta potential measurements, and TEM (Transmission Electron Microscopy) imaging. The cloud points of the polymers were found to be close to the temperature of the human body. Eventually, polymeric carriers were tested as drug delivery systems for the safety, compatibility, and targeting of colorectal cancer cells (CRC). The biological evaluation indicated high compatibility with the representative host cells. Furthermore, it showed that proposed nanosystems might have therapeutic potential as mitigators for 5-FU-induced monocytopenia, cardiotoxicity, and other chemotherapy-associated disorders. Moreover, results show increased cytotoxicity against cancer cells compared to the drug, including a line with a drug resistance phenotype. Additionally, the ability of synthesized carriers to induce apoptosis and necrosis in treated CRC cells has been confirmed. Undoubtedly, the presented aspects of colorectal cancer therapy promise future solutions to overcome the conventional limitations of current treatment regimens for this type of cancer and to improve the quality of life of the patients.

A one-time pneumatic jet-injection of 5-fluorouracil and triamcinolone acetonide for treatment of hypertrophic scars-A blinded randomized controlled trial

BACKGROUND

Patients with hypertrophic scars (HTS) risk reduced quality of life due to itching, pain, poor cosmesis, and restriction of movement. Despite good clinical efficacy, patients are often reluctant to undergo repeated needle injections due to pain or needle phobia.

OBJECTIVES

To evaluate the applicability of needle-free pneumatic jet injection (PJI) and assess changes in hypertrophic scars following a single PJI treatment with 5-fluorouracil (5-FU) and triamcinolone acetonide (TAC).

METHODS

Twenty patients completed this blinded, randomized, controlled, split-scar trial. The intervention side of the HTS received a one-time treatment with PJIs containing a mixture of TAC + 5-FU injected at 5 mm intervals (mean 7 PJI per HTS); the control side received no treatment. Assessments were made at baseline and 4 weeks posttreatment. Outcome measures included change in (1) Vancouver Scar Scale (VSS) total score and subscores, (2) scar volume and surface area assessed by three-dimensional imaging, (3) skin microarchitecture measured by optical-coherence tomography (OCT), (4) photo-assessed scar cosmesis (0-100), (5) patient-reported pain and satisfaction (0-10), and (6) depiction of drug biodistribution after PJI.

RESULTS

PJI with TAC + 5-FU significantly decreased both HTS height (-1 VSS; p = 0.01) and pliability (-1 VSS; p < 0.01) with a nonstatistically significant reduction of -1 in total VSS score (0 in control; p = 0.09). On 3D imaging, a 33% decrease in scar volume (p = 0.016) and a 37% decrease in surface area (p = 0.008) was observed. OCT indicated trends towards smoother scar surface (Ra 11.1-10.3; p = 0.61), normalized dermal microarchitecture (attenuation coefficient: 1.52-1.68; p = 0.44), and a reduction in blood flow between 9% and 17% (p = 0.50-0.79). Despite advances in VSS subscores and OCT, no improved photo-assessed cosmesis was found (-3.2 treatment vs. -1.4 control; p = 0.265). Patient-reported pain was low (2/10) and 90% of the patients that had previously received needle injections preferred PJI to needle injection. Depositions of TAC + FU were imaged reaching deep into the scar at levels corresponding to the reticular dermis.

CONCLUSION

A single PJI injection containing 5-FU and TAC can significantly improve the height and pliability of HTS. PJI is favored by the patients and may serve as a complement to conventional needle injections, especially for patients with needle phobia.

Prospective Randomized Study Comparing Combined Phaco-ExPress and Phacotrabeculectomy in Open Angle Glaucoma Treatment: 12-Month Follow-Up

Purpose of the Study. To compare the efficacy and safety of phacotrabeculectomy (P-Trab) and phacoemulsification with the ExPress (P-ExPress) mini glaucoma shunt implantation. Study Plan. Prospective randomized study. Material and Methods. 85 eyes with cataract and unregulated open angle glaucoma. There were 46 eyes in the P-ExPress and 39 the P-Trab group. Intraocular pressure (IOP), the number of antiglaucoma medications, qualified and complete surgical success (defined as IOP ≤ 18.0 mmHg), visual acuity (CDVA), the number of endothelial cells, and postoperative complications and additional procedures were assessed. Results. After 12 months of observation, the average IOP in the P-Express group went from 26.4 ± 9.3 down to 17.1 ± 5 mmHg (P < 0.05) and from 27.9 ± 12.9 down to 15.9 ± 2.7 mmHg in the P-Trab group (P < 0.05). No significant differences in the amount of medications used after surgery and CDVA were discovered between the groups. In the P-ExPress group, greater loss of endothelial cells was noted (CD_loss%), compared to the P-Trab group. Conclusions. Both P-ExPress and P-Trab have comparable efficacy and similar early postoperative complication profile. The presence of additional implant (as is the case of the ExPress mini glaucoma shunt implantation) may cause progressive loss of endothelial cells.

Local chemotherapeutic agents for the treatment of ocular malignancies

We critically analyze available peer-reviewed literature, including clinical trials and case reports, on local ocular cancer treatments. Recent innovations in many areas of ocular oncology have introduced promising new therapies, but, for the most part, the optimal treatment of ocular malignancies remains elusive.

The Clinical Applications of Fluorouracil in Ophthalmic Practice

Fluorouracil (5-fluorouracil, 5-FU) is a pyrimidine analogue that was originally known for its widespread use as an anticancer drug. The ability of 5-FU to reduce fibroblastic proliferation and subsequent scarring has made it an important adjunct in ocular and periorbital surgeries. It is used in primary glaucoma filtering surgeries and in reviving failing filtering blebs, in dacryocystorhinostomy, pterygium surgery, and in vitreoretinal surgery to prevent proliferative vitreoretinopathy. In addition, 5-FU is also gaining recognition in the treatment and surgical management of ocular surface malignancies like ocular surface squamous neoplasia; however, the specific action of the drug on highly proliferating cells limits its use in primary acquired melanosis of the conjunctiva. When applied topically, this drug has a low rate of sight-threatening adverse effects, is inexpensive, and is easy to administer, making it an important tool in enhancing the success rate in ophthalmic surgery and in reducing the recurrence of ocular surface neoplasia.

Dose, timing and frequency of subconjunctival 5-fluorouracil injections after glaucoma filtering surgery

BACKGROUND

Although adjunctive postoperative 5-fluorouracil (5-FU) injections are known to improve the success rate of glaucoma surgery, it is still unknown what dose, timing and frequency of application will give the best results with respect to the inhibition of postoperative scarring and intraocular pressure regulation. We therefore designed the following retrospective investigation.

METHODS

We studied 172 eyes from 172 patients who had undergone trabeculectomy with adjuvant 5-FU-therapy. Variations of dosage, timing and frequency were analysed retrospectively. Surgery was defined as a complete success when the patient reached an intraocular pressure under 21 mmHg and a reduction of 20% 12 months after the operation. A relative success was achieved with these criteria under additional local medication. Not reaching these postoperative criteria for a complete success was classified as failure.

RESULTS

On average, adjunctive 5-FU-treatment was started 4.6+/-5.85 days postoperatively. The injections contained between 2 mg and 5 mg FU, and the mean total dose was 26.6+/-13.2 mg (range 5-65 mg). Surgery on 94 patients (54.65%) was classified as "complete success", that on 25 patients (14.53%) was classified as "relative success" and that on 53 eyes (30.81%) was classified as "failure" 12 months (+/-3 months) postoperatively. The best results were obtained when the treatment started on or before the first postoperative day (68.0-71.4% complete success; P<0.05). In contrast, an increase in 5-FU dosage did not result in an increased success rate of trabeculectomy. None of the 172 patients suffered from vision-threatening complications such as endophthalmitis or hypotony maculopathy.

CONCLUSION

Early treatment with 5-FU significantly increases the success rates of filtering surgery.

Low-dose 5-fluorouracil trabeculectomy as initial surgery in uncomplicated glaucoma: long-term followup

OBJECTIVE

To compare the effectiveness of trabeculectomy with adjunctive, low-dose, subconjunctival 5-fluorouracil (5-FU) to trabeculectomy alone in patients with uncomplicated glaucoma undergoing their first incisional surgical procedure.

DESIGN

Retrospective, nonrandomized comparative trial.

PARTICIPANTS

Consecutive series of 52 patients and 74 control subjects.

INTERVENTION

Trabeculectomy was performed in all patients. Study patients received adjunctive, subconjunctival injections of 5-FU up to 14 days from the date of surgery.

MAIN OUTCOME MEASURES

Intraocular pressure, number of postoperative antiglaucoma medications, interventions, and complications were evaluated.

RESULTS

Mean followup for all patients was 58.1 +/- 44.1 months (range, 1.1-159.9 months). Mean followup for successful eyes was 55.9 +/- 47.1 months (range, 7.6-159.9 months). The cumulative 5-year success (intraocular pressure [IOP] < or = 21 mmHg) was 77.8% in the 5-FU group and 62.2% in the control group (P = 0.02, Wilcoxon test. Complete success (IOP < or = 21 mmHg without medications) at 5 years was lower in both the 5-FU group (72.3%) and the control group (51.3%). Postoperative mean IOP at 5 years for all successful patients was lower in eyes receiving 5-FU (10.7 +/- 3.6 mmHg vs. 16.0 +/- 6.1 mmHg [P = 0.02, t-test]). For those patients considered to be complete successes, there was no difference in IOP between the two groups of patients at any evaluated time interval. Patients in the 5-FU group were using 0.7 +/- 1.1 medications at final followup compared with 1.8 +/- 1.4 medications in the control group (P = < 0.0001, t test). Bleb-related ocular infection occurred in 6.3% of patients and was more common in patients receiving 5-FU than controls (6 of 52 vs 2 of 74, respectively; P = 0.05, Fischer's exact test).

CONCLUSIONS

Adjunctive, low-dose 5-FU at the time of initial surgery in uncomplicated glaucoma improves long-term IOP control and reduces the need for postoperative, antiglaucoma therapy. Eyes receiving 5-FU are at greater risk of developing late bleb-related ocular infection.

Late complications after glaucoma filtering surgery with adjunctive 5-fluorouracil

We studied 105 patients (105 eyes) operated on for glaucoma with adjunctive fluorouracil, who were followed up for 12 to 48 months (mean, 34.6 +/- 12.9 months). Fifty eyes that had previous glaucoma or cataract extraction or had inflammatory glaucoma had a high risk for postoperative scarring (high-risk group), and 55 eyes had glaucoma surgery as an initial procedure (initial surgery group). An intraocular pressure of 20 mm Hg or less, with or without hypotensive medications, was found in 42 eyes in the high-risk group (84.0%) and in 53 of the eyes in the initial surgery group (96.4%). Of the 105 eyes, an intraocular pressure of 12 mm Hg or less without medication was achieved in 17 eyes in the high-risk group (34.0%) and in 35 eyes in the initial surgery group (63.6%). Late complications in both groups were as follows: endophthalmitis in four eyes (3.8%) (two of the infected blebs were located superiorly and two inferiorly), transient leaking bleb in two eyes (1.9%), hypotony of an extended period with 180 to 360 degrees of filtration in three eyes (2.9%), giant bleb extending over the cornea in two eyes (1.9%), and a transient, mild iridocyclitis in nine eyes (8.6%). Thus, adjunctive fluorouracil after filtering surgery may entail various, mainly bleb-related, late side effects and complications.

Encapsulated filtering bleb. A selective review--new deductions

Filtering bleb encapsulation may, in some cases, be a severe complication following filtering surgery. The cause and mechanism of its development are not known. A selective review of data that might shed some light on these dilemmas, is presented. Based on these data, it is suggested that: (a) non-contractile collagen-producing fibroblasts play a major role in the process of bleb encapsulation, while in wound healing following filtering surgery, contractile fibroblasts are the major components; (b) the process of bleb encapsulation is less sensitive to the toxic effect of 5-Fluorouracil than would healing; (c) collagen-producing fibroblasts may be less sensitive to the destructive effect of 5-Fluorouracil than contractile fibroblasts; (d) inflammatory mediators are important triggers of bleb encapsulation.