Vaginal drug delivery approaches for localized management of cervical cancer

Tumor Cell-Targeting and Tumor Microenvironment-Responsive Nanoplatforms for the Multimodal Imaging-Guided Photodynamic/Photothermal/Chemodynamic Treatment of Cervical Cancer

Purpose

Phototherapy, known for its high selectivity, few side effects, strong controllability, and synergistic enhancement of combined treatments, is widely used in treating diseases like cervical cancer.

Methods

In this study, hollow mesoporous manganese dioxide was used as a carrier to construct positively charged, poly(allylamine hydrochloride)-modified nanoparticles (NPs). The NP was efficiently loaded with the photosensitizer indocyanine green (ICG) via the addition of hydrogen phosphate ions to produce a counterion aggregation effect. HeLa cell membrane encapsulation was performed to achieve the final M-HMnO2@ICG NP. In this structure, the HMnO2 carrier responsively degrades to release ICG in the tumor microenvironment, self-generates O2 for sensitization to ICG-mediated photodynamic therapy (PDT), and consumes GSH to expand the oxidative stress therapeutic effect [chemodynamic therapy (CDT) + PDT]. The ICG accumulated in tumor tissues exerts a synergistic PDT/photothermal therapy (PTT) effect through single laser irradiation, improving efficiency and reducing side effects. The cell membrane encapsulation increases nanomedicine accumulation in tumor tissues and confers an immune evasion ability. In addition, high local temperatures induced by PTT can enhance CDT. These properties of the NP enable full achievement of PTT/PDT/CDT and targeted effects.

Results

Mn2+ can serve as a magnetic resonance imaging agent to guide therapy, and ICG can be used for photothermal and fluorescence imaging. After its intravenous injection, M-HMnO2@ICG accumulated effectively at mouse tumor sites; the optimal timing of in-vivo laser treatment could be verified by near-infrared fluorescence, magnetic resonance, and photothermal imaging. The M-HMnO2@ICG NPs had the best antitumor effects among treatment groups under near-infrared light conditions, and showed good biocompatibility.

Conclusion

In this study, we designed a nano-biomimetic delivery system that improves hypoxia, responds to the tumor microenvironment, and efficiently loads ICG. It provides a new economical and convenient strategy for synergistic phototherapy and CDT for cervical cancer.

Novel Drug Delivery Approaches for the Localized Treatment of Cervical Cancer

Cervical cancer (CC) is the fourth leading cancer type in females globally. Being an ailment of the birth canal, primitive treatment strategies, including surgery, radiation, or laser therapy, bring along the risk of infertility, neonate mortality, premature parturition, etc. Systemic chemotherapy led to systemic toxicity. Therefore, delivering a smaller cargo of therapeutics to the local site is more beneficial in terms of efficacy as well as safety. Due to the regeneration of cervicovaginal mucus, conventional dosage forms come with the limitations of leaking, the requirement of repeated administration, and compromised vaginal retention. Therefore, these days novel strategies are being investigated with the ability to combat the limitations of conventional formulations. Novel carriers can be engineered to manipulate bioadhesive properties and sustained release patterns can be obtained thus leading to the maintenance of actives at therapeutic level locally for a longer period. Other than the purpose of CC treatment, these delivery systems also have been designed as postoperative care where a certain dose of antitumor agent will be maintained in the cervix postsurgical removal of the tumor. Herein, the most explored localized delivery systems for the treatment of CC, namely, nanofibers, nanoparticles, in situ gel, liposome, and hydrogel, have been discussed in detail. These carriers have exceptional properties that have been further modified with the aid of a wide range of polymers in order to serve the required purpose of therapeutic effect, safety, and stability. Further, the safety of these delivery systems toward vital organs has also been discussed.

Cervical cancer: Novel treatment strategies offer renewed optimism

Cervical cancer poses a significant global public health issue, primarily affecting women, and stands as one of the four most prevalent cancers affecting woman globally, which includes breast cancer, colorectal cancer, lung cancer and cervical cancer. Almost every instance of cervical cancer is associated with infections caused by the human papillomavirus (HPV). Prevention of this disease hinges on screening and immunization of the patients, yet disparities in cervical cancer occurrence exist between developed and developing nations. Multiple factors contribute to cervical cancer, including sexually transmitted diseases (STDs), reproductive and hormonal influences, genetics, and host-related factors. Preventive programs, lifestyle improvements, smoking cessation, and prompt precancerous lesion treatment can reduce the occurrence of cervical cancer. The persistency and recurrence of the cases are inherited even after the innovative treatments available for cervical cancer. For patient's ineligible for curative surgery or radiotherapy, palliative chemotherapy remains the standard treatment. Novel treatment strategies are emerging to combat the limited effectiveness of chemotherapy. Nanocarriers offer the promise of concurrent chemotherapeutic drug delivery as a beacon of hope in cervical cancer research. The primary aim of this review study is to contribute to a thorough understanding of cervical cancer, fostering awareness and informed decision-making and exploring novel treatment methods such as nanocarriers for the treatment of cervical cancer. This manuscript delves into cutting-edge approaches, exploring the potential of nanocarriers and other innovative treatments. Our study underscores the critical need for global awareness, early intervention, and enhanced treatment options. Novel strategies, such as nanocarriers, offer renewed optimism in the battle against cervical cancer. This research provides compelling evidence for the investigation of these novel therapeutic approaches within the medical field. Cervical cancer remains a formidable adversary, but with ongoing advancements and unwavering commitment, we move closer to a future where it is a preventable and treatable disease, even in the most underserved regions.

Experimental design approach for development of carboplatin loaded chitosan modified liposomal formulation with improved topical vaginal therapeutic potential

One of the most prevalent cancers affecting women globally is cervical cancer. Cervical cancer is thought to cause 570 000 new cases annually, and standard treatments can have serious side effects. In this work, the main aim is to design, fabrication, and evaluation of carboplatin loaded chitosan coated liposomal formulation (CCLF-I) for vaginal delivery in the treatment of cervical cancer. The particle size and polydispersity index of the CCLF-1 were observed at 269.33 ± 1.15 and 0.40 ± 0.002 nm, respectively. The in vitro mucin binding studies showed good adhesiveness of CCLF-I as compared to plain liposomes (CPLF-I), which was found at 23.49 and 10.80%, respectively. The ex-vivo percent drug permeation from plain liposomal formulation (CPLF-I) was found to be higher in comparison to chitosan coated liposomal formulation which was 56.33% while in CCLF-I it was observed 47.32% this is due to, higher retainability of delivery system (CCLF-I) on targeted site attained by coating of mucoadhesive polymer on liposomes. Ex vivo tissue retention studies exhibited 24.2% of CCLF-I in comparison to 10.34% from plain drug formulation (CPLF-I). The in vivo vaginal retention studies exhibited 14% of drug retention after 24 h from the novel formulation in comparison to 6% from the plain formulation. The developed CCLF-I formulation would open a new avenue in the cervical treatment.

Vaginal Drug Delivery Systems to Control Microbe-Associated Infections

The vagina has been regarded as a crucial route for drug delivery. Despite the wide range of available vaginal dosage forms for vaginal infection control, poor drug absorptivity remains a significant challenge due to various biological barriers in the vagina, such as mucus, epithelium, immune systems, and others. To overcome these barriers, different types of vaginal drug delivery systems (VDDSs), with outstanding mucoadhesive, mucus-penetrating properties, have been designed to enhance the absorptivity of vagina-administered agents in the past decades. In this Review, we introduce a general understanding of vaginal administration, its biological barriers, the commonly used VDDSs, such as nanoparticles and hydrogels, and their applications in controlling microbe-associated vaginal infections. Additionally, further challenges and concerns regarding the design of VDDSs will be discussed.

Three-Dimensionally Printed Vaginal Rings: Perceptions of Women and Gynecologists in a Cross-Sectional Survey

Three-dimensional printing technologies can be implemented for the fabrication of personalized vaginal rings (VRs) as an alternative approach to traditional manufacturing. Although several studies have demonstrated the potential of additive manufacturing, there is a lack of knowledge concerning the opinions of patients and clinicians. This study aimed to investigate the perception of women and gynecologists regarding VRs with personalized shapes. The devices were printed with different designs (traditional, "Y", "M", and flat circle) by Fused Deposition Modeling for a cross-sectional survey with 155 participants. Their anticipated opinion was assessed through a questionnaire after a visual/tactile analysis of the VRs. The findings revealed that most women would feel comfortable using some of the 3D-printed VR designs and demonstrated good acceptability for the traditional and two innovative designs. However, women presented multiple preferences when the actual geometry was assessed, which directly related to their age, previous use of the vaginal route, and perception of comfort. In turn, gynecologists favored prescribing traditional and flat circle designs. Overall, although there was a difference in the perception between women and gynecologists, they had a positive opinion of the 3D-printed VRs. Finally, the personalized VRs could lead to an increase in therapeutic adherence, by meeting women's preferences.

Mucoadhesive 3D printed vaginal ovules to treat endometriosis and fibrotic uterine diseases

Gynaecological health is a neglected field of research that includes conditions such as endometriosis, uterine fibroids, infertility, viral and bacterial infections, and cancers. There is a clinical need to develop dosage forms for gynecological diseases that increase efficacy and reduce side effects and explore new materials with properties tailored to the vaginal mucosa and milieu. Here, we developed a 3D printed semisolid vaginal ovule containing pirfenidone, a repurposed drug candidate for endometriosis. Vaginal drug delivery allows direct targeting of the reproductive organs via the first uterine pass effect, but vaginal dosage forms can be challenging to self-administer and retain in situ for periods of more than 1-3 h. We show that a semisoft alginate-based vaginal suppository manufactured using semisolid extrusion additive manufacturing is superior to vaginal ovules made using standard excipients. The 3D-printed ovule showed a controlled release profile of pirfenidone in vitro in standard and biorelevant release tests, as well as better mucoadhesive properties ex vivo. An exposure time of 24 h of pirfenidone to a monolayer culture of an endometriotic epithelial cell line, 12Z, is necessary to reduce the cells' metabolic activity, which demonstrates the need for a sustained release formulation of pirfenidone. 3D printing allowed us to formulate mucoadhesive polymers into a semisolid ovule with controlled release of pirfenidone. This work enables further preclinical and clinical studies into vaginally administered pirfenidone to assess its efficacy as a repurposed endometriosis treatment.

Formulation and evaluation of paclitaxel-loaded boronated chitosan/alginate nanoparticles as a mucoadhesive system for localized cervical cancer drug delivery

Cervical cancer remains a significant global health challenge, and there is a need for innovative drug delivery systems to improve the efficacy of anticancer drugs. In this study, we developed and evaluated boronated chitosan/alginate nanoparticles (BCHIALG NPs) as a localized mucoadhesive drug delivery system for cervical cancer. Boronated chitosan (BCHI) was synthesized by incorporating 4-carboxyphenylboronic acid onto chitosan (CHI), and boronated chitosan/alginate nanoparticles (BCHIALG NPs) with varying polymer ratios were prepared using an ionic gelation method. The physical properties, drug loading capacity/encapsulation efficiency, mucoadhesive properties, and in vitro drug release profile of the nanoparticles were evaluated. The BCHIALG NPs exhibited a size of less than 390 nm and demonstrated high drug encapsulation efficiency (98.1 - 99.8%) and loading capacity (326.9 - 332.7 μg/mg). Remarkably, the BCHIALG NPs containing 0.03% boronated chitosan and 0.07% alginate showed superior mucoadhesive capability compared to CHIALG NPs, providing sustained drug release and they showed the most promising results as a transmucosal drug delivery system for hydrophobic drugs like paclitaxel (PTX). To the best of our knowledge, this is the first report investigating BCHIALG NPs for cervical drug delivery. The new mucoadhesive paclitaxel formulation could offer an innovative strategy for improving cervical cancer treatment.

Nanoformulation of a novel potent ebselen analog for treatment of vulvovaginal candidiasis

Background: Vulvovaginal candidiasis is primarily caused by Candida albicans (C. albicans). Here, a novel organoselenium compound (G20) was synthesized and evaluated for anti-Candida activity. Methods: Growth-inhibition studies and medium acidification assays to assess the inhibition of the yeast plasma membrane H+-ATPase (Pma1p) were carried out in vitro using G20. A self-nanoemulsifying formulation (SNEP) of G20 was prepared and evaluated for antimycotic activity in a mouse model. Results: G20 inhibited the growth of C. albicans through a mechanism that, at least in part, involves the inhibition of Pma1p. The G20-SNEP formulation significantly reduced vaginal colonization and vaginal inflammation relative to yeast-infected but untreated control mice. Conclusion: G20-SNEP exhibits potent antimycotic activity in a mouse model of vulvovaginal candidiasis.

Hydrogels for Mucosal Drug Delivery

Mucosal tissues are often a desirable site of drug action to treat disease and engage the immune system. However, systemically administered drugs suffer from limited bioavailability in mucosal tissues where technologies to enable direct, local delivery to these sites would prove useful. In this Spotlight on Applications article, we discuss hydrogels as an attractive means for local delivery of therapeutics to address a range of conditions affecting the eye, nose, oral cavity, gastrointestinal, urinary bladder, and vaginal tracts. Considering the barriers to effective mucosal delivery, we provide an overview of the key parameters in the use of hydrogels for these applications. Finally, we highlight recent work demonstrating their use for inflammatory and infectious diseases affecting these tissues.

CMTM6 as a candidate risk gene for cervical cancer: Comprehensive bioinformatics study

Background: CKLF like MARVEL transmembrane domain containing 6 (CMTM6) is an important programmed cell death 1 ligand 1 regulator (PD-L1). CMTM6 was reported as an important regulator of PD-L1 by promoting PD-L1 expression in tumor cells against T cells. However, the function of CMTM6 in cervical cancer is not well characterized. In addition, the role of CMTM6 in the induction of epithelial-mesenchymal transition (EMT) in the context of cervical cancer is unknown. Methods: In this study, we evaluated the role of CMTM6, including gene expression analysis, miRNA target regulation, and methylation characteristic, using multiple bioinformatics tools based on The Cancer Genome Atlas (TCGA) database. The expression of CMTM6 in cervical cancer tissues and non-cancerous adjacent tissues was assessed using immunohistochemistry. In vitro and in vivo function experiments were performed to explore the effects of CMTM6 on growth and metastasis of cervical cancer. Results: Human cervical cancer tissues showed higher expression of CMTM6 than the adjacent non-cancerous tissues. In vitro assays showed that CMTM6 promoted cervical cancer cell invasion, migration, proliferation, and epithelial-mesenchymal transition via activation of mitogen-activated protein kinase (MAPK) c-jun N-terminal kinase (JNK)/p38 signaling pathway. We identified transcription factors (TFs), miRNAs, and immune cells that may interact with CMTM6. Conclusion: These results indicate that CMTM6 is a potential therapeutic target in the context of cervical cancer.

Vaginal Nanoformulations for the Management of Preterm Birth

Preterm birth (PTB) is a leading cause of infant morbidity and mortality in the world. In 2020, 1 in 10 infants were born prematurely in the United States. The World Health Organization estimates that a total of 15 million infants are born prematurely every year. Current therapeutic interventions for PTB have had limited replicable success. Recent advancements in the field of nanomedicine have made it possible to utilize the vaginal administration route to effectively and locally deliver drugs to the female reproductive tract. Additionally, studies using murine models have provided important insights about the cervix as a gatekeeper for pregnancy and parturition. With these recent developments, the field of reproductive biology is on the cusp of a paradigm shift in the context of treating PTB. The present review focuses on the complexities associated with treating the condition and novel therapeutics that have produced promising results in preclinical studies.

The Mucoadhesive Nanoparticle-Based Delivery System in the Development of Mucosal Vaccines

Mucosal tissue constitutes the largest interface between the body and the external environment, regulating the entry of pathogens, particles, and molecules. Mucosal immunization is the most effective way to trigger a protective mucosal immune response. However, the majority of the currently licensed vaccines are recommended to be administered by intramuscular injection, which has obvious shortcomings, such as high production costs, low patient compliance, and lack of mucosal immune response. Strategies for eliciting mucosal and systemic immune responses are being developed, including appropriate vaccine adjuvant, delivery system, and bacterial or viral vectors. Biodegradable mucoadhesive nanoparticles (NPs) are the most promising candidate for vaccine delivery systems due to their inherent immune adjuvant property and the ability to protect the antigen from degradation, sustain the release of loaded antigen, and increase the residence time of antigen at the administration site. The current review outlined the complex structure of mucosa, the mechanism of interaction between NPs and mucosa, factors affecting the mucoadhesion of NPs, and the application of the delivery system based on mucoadhesive NPs in the field of vaccines. Moreover, this review demonstrated that the biodegradable and mucoadhesive NP-based delivery system has the potential for mucosal administration of vaccines.

Mucosal vaccine delivery: A focus on the breakthrough of specific barriers

Mucosal vaccines can effectively induce an immune response at the mucosal site and form the first line of defense against microbial invasion. The induced mucosal immunity includes the proliferation of effector T cells and the production of IgG and IgA antibodies, thereby effectively blocking microbial infection and transmission. However, after a long period of development, the transformation of mucosal vaccines into clinical use is still relatively slow. To date, fewer than ten mucosal vaccines have been approved. Only seven mucosal vaccines against coronavirus disease 2019 (COVID-19) are under investigation in clinical trials. A representative vaccine is the adenovirus type-5 vectored COVID-19 vaccine (Ad5-nCoV) developed by Chen and coworkers, which is currently in phase III clinical trials. The reason for the limited progress of mucosal vaccines may be the complicated mucosal barriers. Therefore, this review summarizes the characteristics of mucosal barriers and highlights strategies to overcome these barriers for effective mucosal vaccine delivery.

Untangling Mucosal Drug Delivery: Engineering, Designing, and Testing Nanoparticles to Overcome the Mucus Barrier

Mucus is a complex viscoelastic gel and acts as a barrier covering much of the soft tissue in the human body. High vascularization and accessibility have motivated drug delivery to various mucosal surfaces; however, these benefits are hindered by the mucus layer. To overcome the mucus barrier, many nanomedicines have been developed, with the goal of improving the efficacy and bioavailability of drug payloads. Two major nanoparticle-based strategies have emerged to facilitate mucosal drug delivery, namely, mucoadhesion and mucopenetration. Generally, mucoadhesive nanoparticles promote interactions with mucus for immobilization and sustained drug release, whereas mucopenetrating nanoparticles diffuse through the mucus and enhance drug uptake. The choice of strategy depends on many factors pertaining to the structural and compositional characteristics of the target mucus and mucosa. While there have been promising results in preclinical studies, mucus-nanoparticle interactions remain poorly understood, thus limiting effective clinical translation. This article reviews nanomedicines designed with mucoadhesive or mucopenetrating properties for mucosal delivery, explores the influence of site-dependent physiological variation among mucosal surfaces on efficacy, transport, and bioavailability, and discusses the techniques and models used to investigate mucus-nanoparticle interactions. The effects of non-homeostatic perturbations on protein corona formation, mucus composition, and nanoparticle performance are discussed in the context of mucosal delivery. The complexity of the mucosal barrier necessitates consideration of the interplay between nanoparticle design, tissue-specific differences in mucus structure and composition, and homeostatic or disease-related changes to the mucus barrier to develop effective nanomedicines for mucosal delivery.

Application of Sol–Gels for Treatment of Gynaecological Conditions—Physiological Perspectives and Emerging Concepts in Intravaginal Drug Delivery

Approaches for effective and sustained drug delivery to the female reproductive tract (FRT) for treating a range of gynaecological conditions remain limited. The development of versatile delivery platforms, such as soluble gels (sol–gels) coupled with applicators/devices, holds considerable therapeutic potential for gynaecological conditions. Sol–gel systems, which undergo solution-to-gel transition, triggered by physiological conditions such as changes in temperature, pH, or ion composition, offer advantages of both solution- and gel-based drug formulations. Furthermore, they have potential to be used as a suitable drug delivery vehicle for other novel drug formulations, including micro- and nano-particulate systems, enabling the delivery of drug molecules of diverse physicochemical character. We provide an anatomical and physiological perspective of the significant challenges and opportunities in attaining optimal drug delivery to the upper and lower FRT. Discussion then focuses on attributes of sol–gels that can vastly improve the treatment of gynaecological conditions. The review concludes by showcasing recent advances in vaginal formulation design, and proposes novel formulation strategies enabling the infusion of a wide range of therapeutics into sol–gels, paving the way for patient-friendly treatment regimens for acute and chronic FRT-related conditions such as bacterial/viral infection control (e.g., STDs), contraception, hormone replacement therapy (HRT), infertility, and cancer.

Drug delivery strategies for management of women's health issues in the upper genital tract

The female upper genital tract (UGT) hosts important reproductive organs including the cervix, uterus, fallopian tubes, and ovaries. Several pathologies affect these organ systems such as infections, reproductive issues, structural abnormalities, cancer, and inflammatory diseases that could have significant impact on women's overall health. Effective disease management is constrained by the multifaceted nature of the UGT, complex anatomy and a dynamic physiological environment. Development of drug delivery strategies that can overcome mucosal and safety barriers are needed for effective disease management. This review introduces the anatomy, physiology, and mucosal properties of the UGT and describes drug delivery barriers, advances in drug delivery technologies, and opportunities available for new technologies that target the UGT.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

Albendazole Release from Silica-Chitosan Nanospheres. In Vitro Study on Cervix Cancer Cell Lines

In this work, a pH-responsive drug-carrier based on chitosan-silica nanospheres was developed as a carrier for Albendazole (ABZ), a poorly water-soluble anthelmintic drug. Spherical silica nanoparticles were obtained by Stöber method and further etched to obtain mesoporous particles with sizes ranging from 350 to 400 nm. The specific BET area of nanoparticles increased from 15 m2/g to 150 m2/g for etched silica, which also exhibited a uniform pore size distribution. X-ray powder diffraction showed the presence of amorphous phase of silica and a low-intensity peak attributed to ABZ for the drug-loaded nanoparticles. A uniform layer of chitosan was obtained ranging from 10 to 15 nm in thickness due to the small concentration of chitosan used (0.45 mg of chitosan/mg of SiO2). The in vitro evaluation of hybrid nanoparticles was performed using four cervical cancer cell lines CaSki, HeLa, SiHa and C33A, showing a significant reduction in cell proliferation (>85%) after 72 h. Therefore, we confirmed the encapsulation and bioavailability of the drug, which was released in a controlled way, and the presence of chitosan delayed the release, which could be of interest for the development of prolonged release drug delivery systems.