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1.
J Photochem Photobiol B ; 255: 112910, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663337

ABSTRACT

The prognosis for patients with advanced-stage pancreatic ductal adenocarcinoma (PDAC) remains dismal. It is generally accepted that combination cancer therapies offer the most promise, such as Folforinox, despite their associated high toxicity. This study addresses the issue of chemoresistance by introducing a complementary dual priming approach to attenuate the DNA repair mechanism and to improve the efficacy of a type 1 topoisomerase (Top1) inhibitor. The result is a regimen that integrates drug-repurposing and nanotechnology using 3 clinically relevant FDA-approved agents (1) Top1 inhibitor (irinotecan) at subcytotoxic doses (2) benzoporphyrin derivative (BPD) as a photoactive molecule for photodynamic priming (PDP) to improve the delivery of irinotecan within the cancer cell and (3) minocycline priming (MNP) to modulate DNA repair enzyme Tdp1 (tyrosyl-DNA phosphodiesterase) activity. We demonstrate in heterotypic 3D cancer models that incorporate cancer cells and pancreatic cancer-associated fibroblasts that simultaneous targeting of Tdp1 and Top1 were significantly more effective by employing MNP and photoactivatable multi-inhibitor liposomes encapsulating BPD and irinotecan compared to monotherapies or a cocktail of dual or triple-agents. These data are encouraging and warrant further work in appropriate animal models to evolve improved therapeutic regimens.


Subject(s)
Carcinoma, Pancreatic Ductal , Irinotecan , Minocycline , Pancreatic Neoplasms , Photochemotherapy , Humans , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/metabolism , Cell Line, Tumor , Minocycline/pharmacology , Minocycline/therapeutic use , Irinotecan/pharmacology , Irinotecan/therapeutic use , Spheroids, Cellular/drug effects , Spheroids, Cellular/pathology , Phosphoric Diester Hydrolases/metabolism , Photosensitizing Agents/pharmacology , Photosensitizing Agents/chemistry , Photosensitizing Agents/therapeutic use , Topoisomerase I Inhibitors/pharmacology , Topoisomerase I Inhibitors/therapeutic use , Topoisomerase I Inhibitors/chemistry , Liposomes/chemistry
2.
J Photochem Photobiol B ; 250: 112811, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38000171

ABSTRACT

Desmoplasia in pancreatic ductal adenocarcinoma (PDAC) is characterized by elevated levels of tumor collagen. Desmoplasia restricts drug delivery in PDAC, contributes to treatment resistance, and is associated with poor survival outcomes. We have previously shown that photodynamic therapy (PDT)-based treatment remediates desmoplasia in orthotopic PDAC tumors by reducing second harmonic generation signals from collagen by >90% and by reducing collagen alignment by >103-fold [19]. Remediating desmoplasia correlated with improved survival outcomes in mice. To understand this phenomenon at a fundamental level, it is important to dissect the impact of therapy on collagen subtypes. In this study, we demonstrate that immunofluorescence profiling of collagen subtypes I, II, III and IV in PDAC tumors 72 h following multiple treatment regimens is predictive of long-term outcomes. Treatment regimens include nanoliposomal irinotecan chemotherapy (nal-IRI; akin to ONIVYDE™), a combination of nal-IRI chemotherapy with PDT encapsulated in a single photoactivable multi-inhibitor liposome (PMIL) and an EGFR-targeted PMIL construct (TPMIL). Results show that the relative tumor content of collagen I, II and III was inversely correlated with overall survival (P ≤ 0.0013, P ≤ 0.0001, P ≤ 0.0011, respectively), while, surprisingly, the relative tumor content of collagen IV was directly correlated with overall survival (P ≤ 0.0001). Similar relationships were observed between the relative tumor content of collagen subtypes and the residual tumor volume at day 88 following treatment. Considering that the relationship between collagen subtypes and treatment outcomes is observed across multiple treatment regimens, immunofluorescence profiling at 72 h following treatment appears to be predictive of tumor growth inhibition and survival in PDAC. Early immunofluorescence collagen subtype profiling may therefore aid in treatment personalization and may inform the dosimetry and scheduling of combination regimens for PDAC, such as chemotherapy and emerging PDT-based combinations, to maximize patient survival benefit.


Subject(s)
Pancreatic Neoplasms , Humans , Animals , Mice , Pancreatic Neoplasms/drug therapy , Treatment Outcome , Collagen , Collagen Type I , Fluorescent Antibody Technique , Liposomes
3.
Front Pediatr ; 11: 1266376, 2023.
Article in English | MEDLINE | ID: mdl-37900685

ABSTRACT

Background: Developmental and epileptic encephalopathies (DEEs) signify a group of heterogeneous neurodevelopmental disorder associated with early-onset seizures accompanied by developmental delay, hypotonia, mild to severe intellectual disability, and developmental regression. Variants in the DNM1 gene have been associated with autosomal dominant DEE type 31A and autosomal recessive DEE type 31B. Methods: In the current study, a consanguineous Pakistani family consisting of a proband (IV-2) was clinically evaluated and genetically analyzed manifesting in severe neurodevelopmental phenotypes. WES followed by Sanger sequencing was performed to identify the disease-causing variant. Furthermore, 3D protein modeling and dynamic simulation of wild-type and mutant proteins along with reverse transcriptase (RT)-based mRNA expression were checked using standard methods. Results: Data analysis of WES revealed a novel homozygous non-sense variant (c.1402G>T; p. Glu468*) in exon 11 of the DNM1 gene that was predicted as pathogenic class I. Variants in the DNM1 gene have been associated with DEE types 31A and B. Different bioinformatics prediction tools and American College of Medical Genetics guidelines were used to verify the identified variant. Sanger sequencing was used to validate the disease-causing variant. Our approach validated the pathogenesis of the variant as a cause of heterogeneous neurodevelopmental disorders. In addition, 3D protein modeling showed that the mutant protein would lose most of the amino acids and might not perform the proper function if the surveillance non-sense-mediated decay mechanism was skipped. Molecular dynamics analysis showed varied trajectories of wild-type and mutant DNM1 proteins in terms of root mean square deviation, root mean square fluctuation and radius of gyration. Similarly, RT-qPCR revealed a substantial reduction of the DNM1 gene in the index patient. Conclusion: Our finding further confirms the association of homozygous, loss-of-function variants in DNM1 associated with DEE type 31B. The study expands the genotypic and phenotypic spectrum of pathogenic DNM1 variants related to DNM1-associated pathogenesis.

4.
Int J Biochem Mol Biol ; 14(4): 40-50, 2023.
Article in English | MEDLINE | ID: mdl-37736391

ABSTRACT

BACKGROUND: There is insufficient data on the prevalence and consequences of eating disorders in Type 2 diabetic patients. OBJECTIVE: To evaluate the presence of eating disorders (ED) and their association with glycaemic control and metabolic parameters in adult patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: A cross-sectional study on 145 patients was conducted in the medicine outpatient unit of HAHC Hospital, Jamia Hamdard tertiary care center. The Eating Attitudes Test (EAT-26) was used to screen for ED in adults with T2DM. The Score of less than 20 and more than 30 on EAT-26 questionnaire was defined as control for participants and relevant medical details like duration of treatment, glycaemic control, complications were recorded. RESULTS: A total of 145 diabetic individuals participated in this study. Out of these, 17.3% of individuals with T2DM screened positive for ED on EAT-26 scale and had a significant positive correlation in <20 groups and a significant negative correlation in >30 groups. CONCLUSION: Our study reveals that eating disorders are not very common in our clinical population of T2DM, the prevalence rates of eating disorders are lower in patients with T2DM than those reported from developed western countries.

5.
J Biomol Struct Dyn ; : 1-13, 2023 Jul 11.
Article in English | MEDLINE | ID: mdl-37434319

ABSTRACT

The GBA1 gene encodes for the lysosomal enzyme glucocerebrosidase (GCase), which maintains glycosphingolipid homeostasis and regulates the autophagy process. Genomic variants of GBA1 are associated with Goucher disease; however, several heterozygous variants of GBA (E326K, T369M, N370S, L444P) are frequent high-risk factors for Parkinson's disease (PD). The underlying mechanism of these variants has been revealed through functional and patient-centered research, but the structural and dynamical aspects of these variants have not yet been thoroughly investigated. In the current study, we used a thorough computational method to pinpoint the structural changes that GBA underwent because of genomic variants and drug binding mechanisms. According to our findings, PD-linked nsSNP variants of GBA showed structural variation and abnormal dynamics when compared to wild-typ. The docking analysis demonstrated that the mutants E326K, N370S, and L444P have higher binding affinities for Ambroxol. Root means square deviation (RMSD), Root mean square fluctuation analysis (RMSF), and MM-GBSA analysis confirmed that the Ambroxol are more stable in the binding site of N370S and L444P, and that their binding affinities are stronger as compared to the wild-type and T369M variants of GBA. The evaluation of hydrogen bonds and the calculation of the free binding energy provided additional evidence in favor of this conclusion. When docked with Ambroxol, GBA demonstrated an increase in binding affinity and catalytic activity. Understanding the therapeutic efficacy and potential against the aforementioned changes in the GBA will be beneficial in order to use more efficient methods for developing novel drugs.Communicated by Ramaswamy H. Sarma.

6.
Adv Sci (Weinh) ; 9(24): e2104594, 2022 08.
Article in English | MEDLINE | ID: mdl-35748165

ABSTRACT

Desmoplasia is characteristic of pancreatic ductal adenocarcinoma (PDAC), which exhibits 5-year survival rates of 3%. Desmoplasia presents physical and biochemical barriers that contribute to treatment resistance, yet depleting the stroma alone is unsuccessful and even detrimental to patient outcomes. This study is the first demonstration of targeted photoactivable multi-inhibitor liposomes (TPMILs) that induce both photodynamic and chemotherapeutic tumor insult, while simultaneously remediating desmoplasia in orthotopic PDAC. TPMILs targeted with cetuximab (anti-EGFR mAb) contain lipidated benzoporphyrin derivative (BPD-PC) photosensitizer and irinotecan. The desmoplastic tumors comprise human PDAC cells and patient-derived cancer-associated fibroblasts. Upon photoactivation, the TPMILs induce 90% tumor growth inhibition at only 8.1% of the patient equivalent dose of nanoliposomal irinotecan (nal-IRI). Without EGFR targeting, PMIL photoactivation is ineffective. TPMIL photoactivation is also sixfold more effective at inhibiting tumor growth than a cocktail of Visudyne-photodynamic therapy (PDT) and nal-IRI, and also doubles survival and extends progression-free survival by greater than fivefold. Second harmonic generation imaging reveals that TPMIL photoactivation reduces collagen density by >90% and increases collagen nonalignment by >103 -fold. Collagen nonalignment correlates with a reduction in tumor burden and survival. This single-construct phototoxic, chemotherapeutic, and desmoplasia-remediating regimen offers unprecedented opportunities to substantially extend survival in patients with otherwise dismal prognoses.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Carcinoma, Pancreatic Ductal/drug therapy , ErbB Receptors/therapeutic use , Humans , Irinotecan/pharmacology , Irinotecan/therapeutic use , Liposomes/therapeutic use , Pancreatic Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Pancreatic Neoplasms
7.
J Obstet Gynaecol India ; 71(5): 495-500, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34602761

ABSTRACT

INTRODUCTION: Pregnancy is characterized by a series of metabolic changes that promote insulin resistance. This could be due to increase in the plasma levels of one or more pregnancy-related hormones such as oestrogen, progesterone, prolactin, cortisol, and human placental lactogen (HPL). The increased insulin resistance in pregnancy is associated with development of diabetes which has implications for the future gestations also. AIMS AND OBJECTIVES: To determine status of insulin resistance in pregnant women and correlate the presence of insulin resistance with obstetric outcome. MATERIAL AND METHOD: A prospective cohort study was conducted in the Department of Obstetrics and Gynaecology, KGMU, Lucknow, over a period of one year. Total 150 pregnant women were enrolled from OPD, out of which 136 women were followed up till delivery. Insulin resistance was calculated by HOMA IR index, twice in whole antenatal period (first in early pregnancy and second in late pregnancy). All women were also tested for GDM by DIPSI test (plasma glucose value after 2 h of 75 gm glucose load irrespective of last meal) as per protocol. RESULTS: In our study, we found 71 women out of 136 (52.2%) were GDM. Total 30 women out of 136 (22.05%) were GGI (Gestational Glucose Intolerance), and total 38 out of 136 (27.9%) women were found to have insulin resistance using HOMA IR ≥ 2 as cut off. Significant correlation was found in between BMI and insulin resistance (p = 0.001) and between GDM and insulin resistance (p = 0.001). Relative risk of development of complications like Preeclampsia, neonatal hypoglycemia, and respiratory distress syndrome was higher in women having insulin resistance and GDM. CONCLUSION: Obstetric complications like preeclampsia, neonatal hypoglycemia, and respiratory distress syndrome are more likely to occur in women with insulin resistance, but larger studies are required to delineate whether insulin resistance alone without development of GDM will have the same implication.

8.
Nano Res ; 14(5): 1344-1354, 2021 May.
Article in English | MEDLINE | ID: mdl-33717420

ABSTRACT

The significance and ability for receptor targeted nanoliposomes (tNLs) to bind to their molecular targets in solid tumors in vivo has been questioned, particularly as the efficiency of their tumor accumulation and selectivity is not always predictive of their efficacy or molecular specificity. This study presents, for the first time, in situ NIR molecular imaging-based quantitation of the in vivo specificity of tNLs for their target receptors, as opposed to tumor selectivity, which includes influences of enhanced tumor permeability and retention. Results show that neither tumor delivery nor selectivity (tumor-to-normal ratio) of cetuximab and IRDye conjugated tNLs correlate with EGFR expression in U251, U87 and 9L tumors, and in fact underrepresent their imaging-derived molecular specificity by up to 94.2%. Conversely, their in vivo specificity, which we quantify as the concentration of tNL-reported tumor EGFR provided by NIR molecular imaging, correlates positively with EGFR expression levels in vitro and ex vivo (Pearson's r= 0.92 and 0.96, respectively). This study provides a unique opportunity to address the problematic disconnect between tNL synthesis and in vivo specificity. The findings encourage their continued adoption as platforms for precision medicine, and facilitates intelligent synthesis and patient customization in order to improve safety profiles and therapeutic outcomes.

9.
Cancers (Basel) ; 14(1)2021 Dec 31.
Article in English | MEDLINE | ID: mdl-35008362

ABSTRACT

The newly developed multimodal imaging system combining raster-scan optoacoustic (OA) microscopy and fluorescence (FL) wide-field imaging was used for characterizing the tumor vascular structure with 38/50 µm axial/transverse resolution and assessment of photosensitizer fluorescence kinetics during treatment with novel theranostic agents. A multifunctional photoactivatable multi-inhibitor liposomal (PMILs) nano platform was engineered here, containing a clinically approved photosensitizer, Benzoporphyrin derivative (BPD) in the bilayer, and topoisomerase I inhibitor, Irinotecan (IRI) in its inner core, for a synergetic therapeutic impact. The optimized PMIL was anionic, with the hydrodynamic diameter of 131.6 ± 2.1 nm and polydispersity index (PDI) of 0.05 ± 0.01, and the zeta potential between -14.9 ± 1.04 to -16.9 ± 0.92 mV. In the in vivo studies on BALB/c mice with CT26 tumors were performed to evaluate PMILs' therapeutic efficacy. PMILs demonstrated the best inhibitory effect of 97% on tumor growth compared to the treatment with BPD-PC containing liposomes (PALs), 81%, or IRI containing liposomes (L-[IRI]) alone, 50%. This confirms the release of IRI within the tumor cells upon PMILs triggering by NIR light, which is additionally illustrated by FL monitoring demonstrating enhancement of drug accumulation in tumor initiated by PDT in 24 h after the treatment. OA monitoring revealed the largest alterations of the tumor vascular structure in the PMILs treated mice as compared to BPD-PC or IRI treated mice. The results were further corroborated with histological data that also showed a 5-fold higher percentage of hemorrhages in PMIL treated mice compared to the control groups. Overall, these results suggest that multifunctional PMILs simultaneously delivering PDT and chemotherapy agents along with OA and FL multi-modal imaging offers an efficient and personalized image-guided platform to improve cancer treatment outcomes.

10.
Nanophotonics ; 10(12): 3199-3214, 2021 Sep.
Article in English | MEDLINE | ID: mdl-37485044

ABSTRACT

Photodynamic priming (PDP), a collateral effect of photodynamic therapy, can transiently alter the tumor microenvironment (TME) beyond the cytotoxic zone. Studies have demonstrated that PDP increases tumor permeability and modulates immune-stimulatory effects by inducing immunogenic cell death, via the release of damage-associated molecular patterns and tumor-associated antigens. Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest of cancers with a stubborn immunosuppressive TME and a dense stroma, representing a challenge for current molecular targeted therapies often involving macromolecules. We, therefore, tested the hypothesis that PDP's TME modulation will enable targeted therapy and result in immune stimulation. Using triple-receptor-targeted photoimmuno-nanoconjugate (TR-PINs)-mediated PDP, targeting epidermal growth factor receptor, transferrin receptor, and human epidermal growth factor receptor 2 we show light dose-dependent TR-PINs mediated cytotoxicity inhuman PDA Ccells (MIAPaCa-2),co-cultured with human pancreatic cancer-associated fibroblasts (PCAFs) in spheroids. Furthermore, TR-PINs induced the expression of heat shock proteins (Hsp60, Hsp70), Calreticulin, and high mobility group box 1 in a light dose and time-dependent manner.TR-PINs-mediated T cell activation was observed in co-cultures of immune cells with the MIA PaCa-2-PCAF spheroids. Both CD4+ T and CD8+ T cells showed light dose and time-dependant antitumor reactivity by upregulating degranulation marker CD107a and interferon-gamma post-PDP. Substantial tumor cell death in immune cell-spheroid co-cultures by day 3 shows the augmentation by antitumor T cell activation and their ability to recognize tumors for a light dose-dependent kill. These data confirm enhanced destruction of heterogeneous pancreatic spheroids mediated by PDP-induced phototoxicity, TME modulation and increased immunogenicity with targeted nanoconstructs.

11.
Eur J Ophthalmol ; 31(3): 1492-1496, 2021 May.
Article in English | MEDLINE | ID: mdl-32615815

ABSTRACT

Fluctuating anterior chamber depth and reverse pupillary block are the most common problems encountered during phacoemulsification following pars plana vitrectomy in cases of cataracts. The sudden deepening of the anterior chamber makes the surgical procedure more cumbersome and increases the risk of intraoperative complications. To solve this problem, we describe a method of balancing the pressure of the anterior and posterior chamber by using a syringe with a flushing needle to inject balanced salt solution into the posterior chamber via the gap between the iris and the anterior capsule of the lens. This technique is especially suitable for complicated cataracts following previous pars plana vitrectomy and high myopia-complicated cataracts. This technique yielded promising results in reducing the difficulties that occur during surgical procedures, reduced the risk of intraoperative complications and simplified the intraocular lens implantation.


Subject(s)
Cataract Extraction , Phacoemulsification , Anterior Chamber , Humans , Lens Implantation, Intraocular , Postoperative Complications , Retrospective Studies , Vitrectomy
12.
J Clin Med ; 9(8)2020 Jul 27.
Article in English | MEDLINE | ID: mdl-32726945

ABSTRACT

Receptor heterogeneity in cancer is a major limitation of molecular targeting for cancer therapeutics. Single-receptor-targeted treatment exerts selection pressures that result in treatment escape for low-receptor-expressing tumor subpopulations. To overcome this potential for heterogeneity-driven resistance to molecular targeted photodynamic therapy (PDT), we present for the first time a triple-receptor-targeted photoimmuno-nanoconjugate (TR-PIN) platform. TR-PIN functionalization with cetuximab, holo-transferrin, and trastuzumab conferred specificity for epidermal growth factor receptor (EGFR), transferrin receptor (TfR), and human epidermal growth factor receptor 2 (HER-2), respectively. The TR-PINs exhibited up to a 24-fold improvement in cancer cell binding compared with EGFR-specific cetuximab-targeted PINs (Cet-PINs) in low-EGFR-expressing cell lines. Photodestruction using TR-PINs was significantly higher than the monotargeted Cet-PINs in heterocellular 3D in vitro models of heterogeneous pancreatic ductal adenocarcinoma (PDAC; MIA PaCa-2 cells) and heterogeneous head and neck squamous cell carcinoma (HNSCC, SCC9 cells) containing low-EGFR-expressing T47D (high TfR) or SKOV-3 (high HER-2) cells. Through their capacity for multiple tumor target recognition, TR-PINs can serve as a unique and amenable platform for the effective photodynamic eradication of diverse tumor subpopulations in heterogeneous cancers to mitigate escape for more complete and durable treatment responses.

13.
Cancers (Basel) ; 12(6)2020 May 29.
Article in English | MEDLINE | ID: mdl-32485915

ABSTRACT

Extensive desmoplasia is a hallmark of pancreatic ductal adenocarcinoma (PDAC), which frequently associates with treatment resistance. Recent findings indicate that a combination of photodynamic therapy and the multi-kinase inhibitor cabozantinib achieved local tumor control and a significant decrease in tumor metastases in preclinical PDAC models, but the underlying therapeutic mechanisms remain unclear. This study elucidates the molecular basis of this multi-agent regimen, focusing on the role of MET signaling. Since MET activation stems from its interaction with hepatocyte growth factor (HGF), which is typically secreted by fibroblasts, we developed heterotypic PDAC microtumor models that recapitulate these interactions. In these models, MET signaling can be constitutively activated through paracrine and autocrine mechanisms. Photodynamic therapy caused significant elevations in HGF secretion by fibroblasts, suggesting it plays a complex role in the modulation of the paracrine HGF-MET signaling cascade in desmoplastic tumors. Blocking MET phosphorylation with adjuvant cabozantinib caused a significant improvement in photodynamic therapy efficacy, most notably by elevating spheroid necrosis at low radiant exposures. These findings highlight that adjuvant photodynamic therapy can augment chemotherapy efficacies, and potentially achieve improved management of desmoplastic PDAC in a more tolerable manner.

14.
J Porphyr Phthalocyanines ; 24(11n12): 1320-1360, 2020.
Article in English | MEDLINE | ID: mdl-37425217

ABSTRACT

Photodynamic therapy is a photochemistry-based approach, approved for the treatment of several malignant and non-malignant pathologies. It relies on the use of a non-toxic, light activatable chemical, photosensitizer, which preferentially accumulates in tissues/cells and, upon irradiation with the appropriate wavelength of light, confers cytotoxicity by generation of reactive molecular species. The preferential accumulation however is not universal and, depending on the anatomical site, the ratio of tumor to normal tissue may be reversed in favor of normal tissue. Under such circumstances, control of the volume of light illumination provides a second handle of selectivity. Singlet oxygen is the putative favorite reactive molecular species although other entities such as nitric oxide have been credibly implicated. Typically, most photosensitizers in current clinical use have a finite quantum yield of fluorescence which is exploited for surgery guidance and can also be incorporated for monitoring and treatment design. In addition, the photodynamic process alters the cellular, stromal, and/or vascular microenvironment transiently in a process termed photodynamic priming, making it more receptive to subsequent additional therapies including chemo- and immunotherapy. Thus, photodynamic priming may be considered as an enabling technology for the more commonly used frontline treatments. Recently, there has been an increase in the exploitation of the theranostic potential of photodynamic therapy in different preclinical and clinical settings with the use of new photosensitizer formulations and combinatorial therapeutic options. The emergence of nanomedicine has further added to the repertoire of photodynamic therapy's potential and the convergence and co-evolution of these two exciting tools is expected to push the barriers of smart therapies, where such optical approaches might have a special niche. This review provides a perspective on current status of photodynamic therapy in anti-cancer and anti-microbial therapies and it suggests how evolving technologies combined with photochemically-initiated molecular processes may be exploited to become co-conspirators in optimization of treatment outcomes. We also project, at least for the short term, the direction that this modality may be taking in the near future.

15.
Nano Lett ; 19(11): 7573-7587, 2019 11 13.
Article in English | MEDLINE | ID: mdl-31518145

ABSTRACT

Despite untiring efforts to develop therapies for pancreatic ductal adenocarcinoma (PDAC), survival statistics remain dismal, necessitating distinct approaches. Photodynamic priming (PDP), which improves drug delivery and combination regimens, as well as tumor photodestruction are key attributes of photodynamic therapy (PDT), making it a distinctive clinical option for PDAC. Localized, high-payload nanomedicine-assisted delivery of photosensitizers (PSs), with molecular specificity and controlled photoactivation, thus becomes critical in order to reduce collateral toxicity during more expansive photodynamic activation procedures with curative intent. As such, targeted photoactivable lipid-based nanomedicines are an ideal candidate but have failed to provide greater than two-fold cancer cell selectivity, if at all, due to their extensive multivariant physical, optical, and chemical complexity. Here, we report (1) a systematic multivariant tuning approach to engineer (Cet, anti-EGFR mAb) photoimmunonanoconjugates (PINs), and (2) stroma-rich heterotypic PDAC in vitro and in vivo models incorporating patient-derived pancreatic cancer-associated fibroblasts (PCAFs) that recapitulate the desmoplasia observed in the clinic. These offer a comprehensive, disease-specific framework for the development of Cet-PINs. Specificity-tuning of the PINs, in terms of PS lipid anchoring, electrostatic modulation, Cet orientation, and Cet surface densities, achieved ∼16-fold binding specificities and rapid penetration of the heterotypic organoids within 1 h, thereby providing a ∼16-fold enhancement in molecular targeted NIR photodestruction. As a demonstration of their inherent amenability for multifunctionality, encapsulation of high payloads of gemcitabine hydrochloride, 5-fluorouracil, and oxaliplatin within the Cet-PINs further improved their antitumor efficacy in the heterotypic organoids. In heterotypic desmoplastic tumors, the Cet-PINs efficiently penetrated up to 470 µm away from blood vessels, and photodynamic activation resulted in substantial tumor necrosis, which was not elicited in T47D tumors (low EGFR) or when using untargeted constructs in both tumor types. Photodynamic activation of the Cet-PINs in the heterotypic desmoplastic tumors resulted in collagen photomodulation, with a 1.5-fold reduction in collagen density, suggesting that PDP may also hold potential for conquering desmoplasia. The in vivo safety profile of photodynamic activation of the Cet-PINs was also substantially improved, as compared to the untargeted constructs. While treatment using the Cet-PINs did not cause any detriment to the mice's health or to healthy proximal tissue, photodynamic activation of untargeted constructs induced severe acute cachexia and weight loss in all treated mice, with substantial peripheral skin necrosis, muscle necrosis, and bowel perforation. This study is the first report demonstrating the true value of molecular targeting for NIR-activable PINs. These constructs integrate high payload delivery, efficient photodestruction, molecular precision, and collagen photomodulation in desmoplastic PDAC tumors in a single treatment using a single construct. Such combined PIN platforms and heterocellular models open up an array of further multiplexed combination therapies to synergistically control desmoplastic tumor progression and extend PDAC patient survival.


Subject(s)
Carcinoma, Pancreatic Ductal/drug therapy , Immunoconjugates/therapeutic use , Nanoconjugates/therapeutic use , Pancreatic Neoplasms/drug therapy , Photosensitizing Agents/therapeutic use , Animals , Antibodies, Monoclonal/therapeutic use , Cancer-Associated Fibroblasts/drug effects , Cancer-Associated Fibroblasts/pathology , Carcinoma, Pancreatic Ductal/pathology , Drug Delivery Systems/methods , ErbB Receptors/antagonists & inhibitors , Humans , Immunoconjugates/administration & dosage , Mice , Nanoconjugates/administration & dosage , Nanomedicine/methods , Organoids/drug effects , Organoids/pathology , Pancreatic Neoplasms/pathology , Photochemotherapy/methods , Photosensitizing Agents/administration & dosage
16.
Photochem Photobiol ; 95(1): 364-377, 2019 01.
Article in English | MEDLINE | ID: mdl-30125366

ABSTRACT

With the rapidly emerging designs and applications of light-activated, photodynamic therapy (PDT)-based nanoconstructs, photonanomedicines (PNMs), an unmet need exists to establish whether conventional methods of photochemical and photophysical characterization of photosensitizers are relevant for evaluating new PNMs in order to intelligently guide their design. As a model system, we build on the clinical formulation of benzoporphyrin derivative (BPD), Visudyne® , by developing a panel of nanolipid formulations entrapping new lipidated chemical variants of BPD with differing chemical, photochemical and photophysical properties. These are 16:0 and 20:0 lysophosphocholine-BPD (16:0/20:0 BPD-PC), DSPE-PEG-BPD and BPD-cholesterol. We show that Visudyne® was the most phototoxic formulation to OVCAR-5 cells, and the least effective was liposomal DSPE-PEG-BPD. However, these differences did not match their optical, photophysical and photochemical properties, as the static BPD quenching was highest in Visudyne, which also exhibited the lowest generation of singlet oxygen. Furthermore, we establish that OVCAR-5 cell phototoxicity also does not correlate with rates of photosensitizer photobleaching and fluorescence quantum yields in any nanolipid formulations. These findings warrant critical future studies into subcellular targets and molecular mechanisms of phototoxicity of photodynamic nanoconstructs, as more reliable prognostic surrogates for predicting efficacy to appropriately and intelligently guide their design.


Subject(s)
Lipids/chemistry , Nanoparticles/chemistry , Ovarian Neoplasms/drug therapy , Photochemical Processes , Porphyrins/chemistry , Porphyrins/therapeutic use , Cell Line, Tumor , Female , Humans , Ovarian Neoplasms/pathology
17.
Photochem Photobiol ; 95(1): 419-429, 2019 01.
Article in English | MEDLINE | ID: mdl-30499113

ABSTRACT

A major objective in developing new treatment approaches for lethal tumors is to reduce toxicity to normal tissues while maintaining therapeutic efficacy. Photodynamic therapy (PDT) provides a mechanistically distinct approach to treat tumors without the systemic toxicity of chemotherapy drugs. PDT involves the light-based activation of a small molecule, a photosensitizer (PS), to generate reactive molecular species (RMS) that are toxic to target tissue. Depending on the PS localization, various cellular and subcellular components can be targeted, causing selective photodamage. It has been shown that targeted lysosomal photodamage followed by, or simultaneous with, mitochondrial photodamage using two different PS results in a considerable enhancement in PDT efficacy. Here, two liposomal formulations of benzoporphyrin derivative (BPD): (1) Visudyne (clinically approved) and (2) an in-house formulation entrapping a lipid conjugate of BPD are used in combination with direct PS localization to mitochondria, endoplasmic reticulum and lysosomes, enabling simultaneous photodamage to all three organelles using a single wavelength of light. Building on findings by our group, and others, this study demonstrates, for the first time in a 3D model for ovarian cancer, that BPD-mediated photodestruction of lysosomes and mitochondria/ER significantly enhances PDT efficacy at lower light doses than treatment with either PS formulation alone.


Subject(s)
Lipids/chemistry , Liposomes , Models, Biological , Ovarian Neoplasms/drug therapy , Photosensitizing Agents/therapeutic use , Porphyrins/therapeutic use , Verteporfin/therapeutic use , Cell Line, Tumor , Dose-Response Relationship, Radiation , Drug Therapy, Combination , Female , Humans , Photosensitizing Agents/administration & dosage , Porphyrins/administration & dosage , Verteporfin/administration & dosage
18.
Lasers Surg Med ; 50(5): 499-505, 2018 07.
Article in English | MEDLINE | ID: mdl-29527710

ABSTRACT

OBJECTIVE: A relatively low level of lysosomal photodamage has been shown capable of promoting the efficacy of photodamage simultaneously or subsequently directed to mitochondrial/ER sites. The procedure has hitherto involved the use of two photosensitizing agents that require irradiation at two different wavelengths and different formulation techniques. This, together with different pharmacokinetic profiles of the photosensitizers, adds a layer of complexity to a protocol that we have sought to circumvent. In this study, liposomal formulations were used to direct photodamage created by benzoporphyrin derivative (BPD, Verteporfin) to lysosomes, mitochondria and the ER. This resulted in the development of an optimal targeting profile using a single agent and a single wavelength of activating irradiation. MATERIALS/METHODS: These studies were carried out in monolayer cultures of OVCAR5 tumor cells. BPD localization was modified by lipid anchoring and formulation in liposomes, and was assessed by fluorescence microscopy. Irradiation was carried out at 690 ± 10 nm with photodamage assessed also using fluorescent probes and microscopy. RESULTS: BPD normally localizes in a wide variety of sub-cellular loci that include both mitochondria and the ER, but lysosomes are spared from photodamage. Using a liposomal formulation containing BPD anchored to a lipid resulted in the targeting of lysosomes. A mixture of liposomes containing "free" and "anchored" BPD was shown to significantly promote photokilling. Eliminating cholesterol from the formulation of the anchored product enhanced lysosomal photodamage; prior studies had revealed that excess cholesterol can have a cytoprotective effect when lysosomes are the PDT target. DISCUSSION: The ability of a liposomal formulation to change localization patterns permits directing photodynamic therapy toward specific sub-cellular loci, thereby promoting photokilling. Incorporating chemotherapeutic agents into such formulations could represent a logical next step in assessing the ability of directed photodamage to enhance tumor eradication. Lasers Surg. Med. 50:499-505, 2018. © 2018 Wiley Periodicals, Inc.


Subject(s)
Liposomes , Photochemotherapy/methods , Photosensitizing Agents/administration & dosage , Verteporfin/administration & dosage , Cell Culture Techniques , Cell Line, Tumor , Endoplasmic Reticulum/drug effects , Humans , Lysosomes/drug effects , Mitochondria/drug effects
19.
Pak J Med Sci ; 33(5): 1205-1209, 2017.
Article in English | MEDLINE | ID: mdl-29142565

ABSTRACT

OBJECTIVE: The objective was to assess the role of homocysteine in the development of atherosclerosis in common carotid artery in the carbamazepine treated epileptic patients. METHODS: This study was conducted in the Department of Biochemistry, Basic Medical Sciences Institute (BMSI), Jinnah Postgraduate Medical Center (JPMC), Karachi. Three hundred individuals, aged 34 ± 9.5 years were selected and divided into three groups. Each group comprised of 100 subjects labeled as Group-A (control group had healthy individuals), Group-B (newly diagnosed epileptic patients without antiepileptic therapy), Group-C (epileptic patients on Carbamazepine therapy, which was further subdivided into C-I having epileptic patients on Carbamazepine therapy less than 1 year n=33, C-II had epileptic patients on Carbamazepine therapy 1-2 years n = 33 and C-III comprised of epileptic patients on Carbamazepine therapy more than 2 years n = 34). Blood concentration of homocysteine was measured and ultrasound of Common Carotid Artery for intima-media thickness was performed. RESULTS: Significantly elevated level of homocysteine was observed in epileptic patients on CBZ therapy. Common Carotid Artery Intima-media thickness (CCA IMT) was observed significantly high throughout group C but it was more profound in Group-C-III. Homocysteine was found positively correlated with right CCA IMT, left CCA IMT and mean CCA IMT. CONCLUSION: Hyperhomocysteinemia was linked with increased risk of atherosclerosis in CBZ treated epileptic patients.

20.
J Biomed Opt ; 22(12): 1-6, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28853247

ABSTRACT

The emergence of fluorescently labeled therapeutic antibodies has given rise to molecular probes for image-guided surgery. However, the extraneous interstitial presence of an unbound and nonspecifically accumulated probe gives rise to false-positive detection of tumor tissue and margins. Thus, the concept of tumor-cell activation of smart probes provides a potentially superior mechanism of delineating tumor margins as well as small tumor deposits. The combination of molecular targeting with intracellular activation circumvents the presence of extracellular, nonspecific signals of targeted probe accumulation. Here, we present a demonstration of the clinical antibodies cetuximab (cet, anti-EGFR mAb) and trastuzumab (trast, anti-HER-2 mAb) conjugated to Alexa Fluor molecules and IRDye QC-1 quencher optimized at the ratio of 1∶2∶6 to provide the greatest degree of proteolytic fluorescence activation, synonymous with intracellular lysosomal degradation. The cet-AF-Q-C1 conjugate (1∶2∶6) provides up to 9.8-fold proteolytic fluorescence activation. By preparing a spectrally distinct, irrelevant sham IgG-AF-QC-1 conjugate, a dual-activatable probe approach is shown to enhance the specificity of imaging within an orthotopic AsPC-1 pancreatic cancer xenograft model. The dual-activatable approach warrants expedited clinical translation to improve the specificity of image-guided surgery by spectrally decomposing specific from nonspecific probe accumulation, binding, and internalization.


Subject(s)
Cetuximab , Fluorescent Dyes , Molecular Probes , Surgery, Computer-Assisted , Trastuzumab , Animals , Female , Immunoglobulin G
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