Modified painless photodynamic therapy for facial multiple actinic keratosis in China: A prospective split-face control study.

BACKGROUND: Aminolevulinic acid photodynamic therapy (ALA-PDT) is an effective treatment for multiple actinic keratosis (AK). However, PDT-induced pain often discontinues the therapy to reduce its efficacy, limiting its application. If modified painless PDT schedule with shorter photosensitizer dressing and higher dose illumination could achieve good efficacy in AK, it is still unknown. OBJECTIVES: To explore the efficacy and pain tolerance of the modified painless PDT (M-PDT) in facial multiple AK. METHODS: A split-face controlled clinical study including 14 patients with facial multiple AK was conducted. The patients received conventional PDT (C-PDT) on the left and M-PDT in the contralateral area. The left area (C-PDT) was illuminated by a red light-emitting diode light (144 J/cm2 ) after applying the 10% ALA cream for 3 h; the other had illumination for a total light dose of 288 J/cm2 after applying the 10% ALA cream for 0.5 h. The primary endpoint was the lesion clearance rate at 1-month postthree sessions of PDT. Secondary endpoints included pain scores, the incidence of adverse events during treatment, and cosmetic outcomes. RESULTS: At 1 month following three treatments, the total lesion clearance rate was comparable between M-PDT and C-PDT (91.6% vs. 89.0%). While the lesion clearance rate of M-PDT was higher than that of C-PDT in the Grade III lesions (86.5% vs. 72.0%, respectively) (p < 0.05). M-PDT achieved a 100% lesion clearance rate for Grade I lesions earlier than C-PDT, with M-PDT treated twice and C-PDT treated thrice. Moreover, the pain score during illumination was significantly lower for M-PDT than for C-PDT (p < 0.01). Regarding photoaging, the Global Subjective Skin Aging Assessment score showed that the total and atrophy scores of C-PDT and M-PDT were significantly improved, and M-PDT also reduced discoloration. There was no significant difference in adverse reactions between C-PDT and M-PDT. CONCLUSIONS: M-PDT is comparable to C-PDT's efficacy for treating facial multiple AK, resulting in much lower pain scores.

Fluorescence kinetics study of twice laser irradiation based HpD-PDT for nonmelanoma skin cancer.

BACKGROUND: Hematoporphyrine injection (HpD)-based photodynamic therapy (HpD-PDT) has emerged as a promising cancer therapy. However, its tumor-targeting ability and metabolokinetics in nonmelanoma skin cancer (NMSC) have not been well explored. Importantly, photodynamic diagnosis is widely used for cancer lesion assessment and positioning to ensure effective therapy, while the photosensitizer metabolic kinetics study is utilized for biosafety assessment and light-protection instruction. These are particularly important for the optimization of therapeutic parameters. OBJECTIVES: In the present study, NMSC patients were subjected to twice laser irradiation-based HpD-PDT strategy. Broadly, the study aimed to assess long-term variations in fluorescence (FL) intensity in vivo in NMSC patients after intravenous (i.v.) administration of HpD, and thus obtain information regarding metabolism, biosafety, and light-protection instruction for HpD during the therapy. METHODS: In vitro experiments were used for the evaluation of absorption and fluorescent characterization of HpD in aqueous solution and cutaneous squamous cell carcinoma (SCC) cells. For in vivo assessment, 20 patients with NMSC, including SCC, basal cell carcinoma (BCC), Bowen disease (BD), extramammary Paget's disease (EMPD), and malignant proliferating tricholemmoma (APT), were recruited, and treated with HpD-PDT. To evaluate the selectivity and pharmacokinetics of HpD in vivo, relative changes in FL intensity for lesional, perilesional, and nonlesional skin of nonmelanoma skin cancer patients, before and after HpD injection, were semiquantitatively analyzed for 1 month, using the FL detection system and Wood's lamp. RESULTS: The absorption and FL spectra were detected and semiquantitatively analyzed in HpD diluted solution and SCC cells after coincubation with HpD. After i.v. administration of HpD in EMPD patients, FL was detected in the skin lesions at 24 hours, and it was characterized by clear edges. Importantly, FL intensity in the skin lesions increased significantly at 48 and 72 hours postinjection, which was suitable for HpD-PDT. After 72 h, it decreased gradually and reached close to the baseline value at 4 weeks postinjection. No severe side effects were observed during HpD injection and the therapy. Urinary tract infection was recorded in one patient (with a previous history of recurrent urinary tract infections) after HpD-PDT, and the patient was cured afterward. Transient light was observed in two patients after HpD-PDT and they soon recovered after therapy. CONCLUSIONS: The present study reported a significant increase in FL intensities at 48 and 72 hours after i.v. administration of HpD in patients with nonmelanoma skin cancers, which indicated accumulation of HpD at the cancer site. Importantly, HpD was found to be safe for NMSC patients. After therapy, FL intensities decreased, which indicated expending and metabolization of HpD. Thus, the results of the present study highlighted the suitability of a twice red-light laser irradiation strategy for the application of HpD-PDT in nonmelanoma skin cancer treatment.

Identification of Boronate-Containing Diarylpyrimidine Derivatives as Novel HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors.

In this study, privileged boronic acid ester was introduced into the right wing of etravirine (ETR) to obtain a series of novel boronate-containing derivatives. These newly synthesized derivatives were evaluated for their anti-HIV potency in MT-4 cells using the MTT method, and their inhibitory activity to HIV-1 reverse transcriptase (RT) was assayed by the ELISA method. Most of the synthesized compounds displayed promising antiviral activity against the wild-type and a wide range of HIV-1 mutant strains. In particular, 4a exhibited the most potent activity against the wild-type and a panel of single mutations (L100I, K103N, Y181C, and E138K) with EC50 values ranging from 0.005 to 0.648 µM, which were much superior to those of nevirapine (EC50 = 0.151 µM). Moreover, 4b turned out to be an effective inhibitor against the double-mutant strains F227L + V106A and RES056 with EC50 values of 3.21 and 2.30 µM, respectively. RT inhibition activity and molecular docking were also investigated.

Exploiting the hydrophobic channel of the NNIBP: Discovery of novel diarylpyrimidines as HIV-1 NNRTIs against wild-type and K103N mutant viruses.

To further explore the chemical space surrounding the "hydrophobic channel" of the NNRTI binding pocket (NNIBP), a new series of diarylpyrimidines (DAPYs) were designed and synthesized as potent HIV-1 non-nucleoside RT inhibitors (NNRTIs). The target compounds were evaluated for anti-HIV potency in MT-4 cells. Most of the synthesized DAPYs exhibited moderate to excellent activity against the HIV-1 wild-type (WT) strain with EC50 values ranging from 16 nM to 0.722 µM. Interestingly, few compounds displayed remarkable activity in inhibiting K103N mutant virus with EC50 values ranging from 39 nM to 1.708 µM. Notably, FS2 (EC50(IIIB) = 16 nM, EC50(K103N) = 39 nM, SI = 294) was identified as the most significant compound, which was considerably more potent than nevirapine, lamivudine, and comparable to zidovudine. Additionally, the HIV-1 RT inhibition assay confirmed their binding target. Preliminary structure-activity relationships (SARs) and molecular modeling studies were also performed, providing significant suggestions for further optimization.

Design, synthesis, and antiviral evaluation of novel piperidine-substituted arylpyrimidines as HIV-1 NNRTIs by exploring the hydrophobic channel of NNIBP.

Herein, alkenylpiperidine and alkynylpiperidine moieties were introduced into the left wing of DAPYs (diarylpyrimidines) to explore the new site of the NNIBP (non-nucleoside inhibitor binding pocket) protein-solvent interface region via the structure-based drug design strategy. All the synthesized compounds displayed nanomolar to submicromolar activity against WT (wild-type) HIV-1. Among all, compound FT1 (EC50 = 19 nM) was found to be the most active molecule, which is better than NVP (EC50 = 0.10 µM). In addition, most of the compounds displayed micromolar activity against K103N and E138K mutant strains, while FT1 (EC50(K103N) = 50 nM, EC50(E138K) = 0.19 µM) still has the most effective activity. The molecular dynamics simulation studies revealed that the presence of pyridine moiety of FT1 was essential and played a significant role in its binding with RT (reverse transcriptase).

Molecular design opportunities presented by solvent-exposed regions of target proteins.

Solvent-exposed regions, or solvent-filled pockets, within or adjacent to the ligand-binding sites of drug-target proteins provide opportunities for substantial modifications of existing small-molecular drug molecules without serious loss of activity. In this review, we present recent selected examples of exploitation of solvent-exposed regions of proteins in drug design and development from the recent medicinal-chemistry literature.

Targeting the hydrophobic channel of NNIBP: discovery of novel 1,2,3-triazole-derived diarylpyrimidines as novel HIV-1 NNRTIs with high potency against wild-type and K103N mutant virus.

Enlightened by our previous efforts to modify diarylpyrimidines as HIV-1 non-nucleoside reverse transcriptase (RT) inhibitors (NNRTIs) and the reported crystallographic studies, we designed and synthesized novel 1,2,3-triazole-derived diarylpyrimidine derivatives via the CuAAC "click reaction", to make additional interactions with the hydrophobic channel in the NNRTI binding pocket. The newly synthesized compounds were evaluated for anti-HIV potency in MT-4 cells. All the compounds showed favorable activity against the wild-type HIV-1 strain with an EC50 of 0.013-5.62 µM. Interestingly, some compounds displayed remarkable potency in inhibiting K103N mutant virus, a key drug-resistant mutant to NNRTIs. Among them, meta-methylbenzoate (ZL2, EC50(IIIB) = 0.020 µM, EC50(K103N) = 0.043 µM, CC50 > 241.52 µM), para-methylbenzoate (ZL3, EC50(IIIB) = 0.013 µM, EC50 (K103N) = 0.022 µM, CC50 > 241.52 µM) and para-phenol (ZL7, EC50(IIIB) = 0.014 µM, EC50 (K103N) = 0.054 µM, CC50 = 2.1 µM) derivatives are the three most promising compounds which are superior to the first-line antiretroviral drug efavirenz (EC50(IIIB) = 0.003 µM, EC50 (K103N) = 0.11 µM, CC50 > 6.34 µM) against the K103N mutant strain. More encouragingly, ZL2 and ZL3 exhibited much lower cytotoxicity and a high selection index of >10 000 compared with all the control drugs (AZT, 3TC, NVP, EFV, and ETV). The detailed structure-activity relationship (SAR), enzymatic inhibitory activity and docking study of the representative compounds are also discussed. Furthermore, the preliminary physicochemical properties and the early metabolic stability of representative compounds were examined to evaluate their drug-like properties.

First discovery of a potential carbonate prodrug of NNRTI drug candidate RDEA427 with submicromolar inhibitory activity against HIV-1 K103N/Y181C double mutant strain.

In the present work, we described the synthesis, antiviral profiles and metabolic stability in human plasma of compound 6, a potential carbonate prodrug of HIV-1 NNRTI drug candidate RDEA427. Compound 6 was found to inhibit the wild-type (WT) and K103N/Y181C double mutant HIV-1 strains at nano- and submicromolar concentrations, respectively. Moreover, it displayed potent HIV-1 reverse transcriptase inhibitory activity (IC50 = 0.264 µM). Further stability test in human plasma showed that 6 could release its active form RDEA427 in a linearly time-independent manner, possibly acting as a potential prodrug.

Discovery of novel diarylpyrimidines as potent HIV-1 NNRTIs by investigating the chemical space of a less explored "hydrophobic channel".

A new series of diarylpyrimidines (DAPYs) were designed, synthesized and evaluated as novel HIV-1 NNRTIs to further explore the chemical space surrounding the "hydrophobic channel" of the NNRTI binding pocket (NNIBP), guided by the comprehensive analysis of X-ray structural biology data of HIV-1 RT/NNRTI complexes and molecular modeling. Encouragingly, most of the synthesized DAPYs were found to be active against the HIV-1 wild-type (WT) strain with EC50 values ranging from 3 nM to 63 nM, and displayed significantly reduced cytotoxicity compared with etravirine (ETV) and rilpivirine (RPV). Among them, two most promising compounds Z10 (EC50 = 3 nM) and Z13 (EC50 = 3 nM) showed equivalent potency against the HIV-1 WT strain to the reference drugs efavirenz (EFV, EC50 = 3 nM) and ETV (EC50 = 3 nM). Notably, Z13 also showed the most potent activity against HIV-1 mutant strains including K103N (EC50 = 10 nM), E138K (EC50 = 22 nM) and RES056 (EC50 = 0.935 µM). Against mutant strains Y181C, Y188L and F227L + V106A, Z17 showed double-digit nanomolar inhibitory activity with EC50 values 27 nM, 98 nM and 30 nM, respectively. The structure-activity relationships (SARs) and molecular docking studies provided important clues for further molecular elaboration. Collectively, this study provides useful information to guide lead optimization and drug discovery via the exploration of this seldom investigated region.

1-Hydroxypyrido[2,3-d]pyrimidin-2(1H)-ones as novel selective HIV integrase inhibitors obtained via privileged substructure-based compound libraries.

A small library containing 3-hydroxyquinazoline-2,4(1H,3H)-dione and 1-hydroxypyrido[2,3-d]pyrimidin-2(1H)-one scaffolds was obtained via the copper(I)-catalyzed azidealkyne cycloaddition (CuAAC) reaction and evaluated for their anti-HIV activity in MT-4 cells. Among the synthesized compounds, several 1-hydroxypyrido[2,3-d]pyrimidin-2(1H)-one derivatives showed remarkable anti-HIV potency with EC50 values ranging from 0.92 to 26.85µM. The most active one, IIA-2, also showed remarkable and selective potency against HIV type 1 integrase (IN). To the best of our knowledge, this is the first report showing that 1-hydroxypyrido[2,3-d]pyrimidin-2(1H)-ones are selective HIV IN inhibitors. Preliminary structure-activity relationship (SAR) studies suggested that the divalent metal ion chelators and the nature and position of substituents around the core are important for antiviral potency. Molecular modeling has been used to predict the binding site of the pyrido[2,3-d]pyrimidin-2(1H)-one core in HIV type 1 IN and suggestions are made for improvement of its inhibitory activity.

First discovery of novel 3-hydroxy-quinazoline-2,4(1H,3H)-diones as specific anti-vaccinia and adenovirus agents via 'privileged scaffold' refining approach.

A series of 1,2,3-triazolyl 3-hydroxy-quinazoline-2,4(1H,3H)-diones was constructed utilizing Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) method. The biological significance of the novel synthesized quinazolines was highlighted by evaluating them in vitro for antiviral activity, wherein several compounds exhibited excellent activity specifically against vaccinia and adenovirus. Especially, 24b11 displayed the most potent inhibitory activity against vaccinia with an EC50 value of 1.7µM, which was 15 fold than that of the reference drug Cidofovir (EC50=25µM). 24b13 was the most potent compound against adenovirus-2 with an EC50 value of 6.2µM, which proved lower than all the reference drugs. Preliminary structure-activity relationships were also discussed. To the best of our knowledge, no data are present in the literature on antiviral activity of 3-hydroxy-quinazoline-2,4(1H,3H)-diones against DNA-viruses. Thus, these findings warrant further investigations (library expansion and compound refinement) on this novel class of antiviral agents.

Arylazolyl(azinyl)thioacetanilides. Part 20: Discovery of novel purinylthioacetanilides derivatives as potent HIV-1 NNRTIs via a structure-based bioisosterism approach.

By means of structure-based bioisosterism approach, a series of novel purinylthioacetanilide derivatives were designed, synthesized and evaluated as potent HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs). Some of the tested compounds were found to be active against wild-type (WT) HIV-1(IIIB) with EC50 in the range of 0.78-4.46µM. Among them, LAD-8 displayed the most potent anti-HIV activity (EC50=0.78µM, SI=24). In addition, LBD-6 showed moderate activity against L100I mutant (EC50=5.64µM) and double mutant strain RES056 (EC50=22.24µM). Preliminary structure-activity relationships (SARs) were discussed in detail. Molecular modeling study was used to predict the optimal conformation in the NNRTI binding site, which may play a guiding role in further rational optimization.

Discovery of 2-pyridone derivatives as potent HIV-1 NNRTIs using molecular hybridization based on crystallographic overlays.

Based on crystallographic overlays of the known inhibitors TMC125 and R221239 complexed in RT, we designed a novel series of 4-phenoxy-6-(phenylamino)pyridin-2(1H)-one derivatives as HIV NNRTIs by molecular hybridization approach. The biological testing results indicated that 2-pyridone scaffold of these inhibitors was indispensable for their anti-HIV-1 activity, and substitution of halogen at the 3-position of the 2-pyridone ring would decrease the anti-HIV activity. Four most potent compounds had anti-HIV-1 IIIB activities at low micromolar concentrations (EC50=0.15-0.84 µM), comparable to that of nevirapine and delavidine. Some compounds were selected to test their anti-HIV-1 RT inhibitory action and to perform molecular modeling studies to predict the binding mode of these 2-pyridone derivatives.

The combination of holmium laser and ALA-PDT for Bowenoid Papulosis with diffuse large B-cell lymphoma.

Bowenoid Papulosis (BP) is an anogenital pre-malignancy. BP with immunosuppression may recur, worsen, or possibly evolve into squamous cell carcinoma or Bowen's disease (BD), and it may also become resistant to conventional treatment. Here, we describe a complex case of BP together with BD and Diffuse Large B-Cell Lymphoma that was effectively treated with a holmium laser in conjunction with 5-Aminolevulinic Acid Photodynamic Therapy (ALA-PDT). The lesion totally vanished and the affected area remained intact with no recurrence at five years.

Successful treatment by a chlorin e6 derivative mediated photodynamic therapy combined holmium laser for cervical and vaginal giant condyloma acuminata and low-grade intraepithelial neoplasia:A case report.

Photodynamic therapy (PDT) is proved effective for treating low-grade squamous intraepithelial lesions (LSIL) and condylomata acuminata (CA). 5-Aminolevulinicacid (5-ALA) is the most common applied photosensitizer, but high rate of unbearable pain and relative long incubation time were reported. Here, we report a 27-year-old woman suffering from cervical and vaginal giant CA with LSIL involving the whole right vaginal fornix, cervical surface, and vaginal wall. Holmium yttrium aluminum garnet (Ho: YAG) laser was first applied to remove the giant CA lesions. STBF, a derivative of chlorin e6 (Ce6) was then applied on suspicious lesions as a new photosensitizer for 1 h. Lesions were exposed to LED illumination with a wavelength of 630 nm and light dose of 200-284 J/cm2 for cervical canal and the vaginal surfaces, 100-150 J/cm2 for cervix surface. Vaginal giant CA and LSIL lesions got complete remission at 6-month follow-up. Mild tolerable adverse reactions were observed after STBF-PDT and relieved in 24 h. Thus, the combination of Ho: YAG laser and STBF-PDT may be a novel option for cervical and vaginal giant CA and LSIL, especially for special vaginal fornix areas.

ICG-labeled PD-L1-antagonistic affibody dimer for tumor imaging and enhancement of tumor photothermal-immunotherapy.

In clinical practice, tumor-targeting diagnosis and immunotherapy against programmed death ligand 1 (PD-L1) have a significant impact. In this research, a PD-L1-antagonistic affibody dimer (ZPD-L1) was successfully prepared through Escherichia coli expression system, and conjugated with the photosensitizer of ICG via N-hydroxysuccinimide (NHS) ester to develop a novel tumor-targeting agent (ICG-ZPD-L1) for both tumor imaging diagnosis and photothermal-immunotherapy simultaneously. In vitro, ZPD-L1 could specifically bind to PD-L1-positive LLC and MC38 tumor cells, and ICG-ZPD-L1-mediated photothermal therapy (PTT) also showed excellent phototoxicity to these tumor cells. In vivo, ICG-ZPD-L1 selectively enriched into the PD-L1-positive MC38 tumor tissues, and the high-contrast optical imaging of tumors was obtained. ICG-ZPD-L1-mediated PTT exhibited a potent anti-tumor effect in vivo due to its remarkable photothermal properties. Furthermore, ICG-ZPD-L1-mediated PTT significantly induced the immunogenic cell death (ICD) of primary tumors, promoted maturation of dendritic cells (DCs), up-regulated anti-tumor immune response, enhanced immunotherapy, and superiorly inhibited the growth of metastatic tumors. In addition, ICG-ZPD-L1 showed favorable biosafety throughout the brief duration of treatment. In summary, these results suggest that ICG-ZPD-L1 is a multifunctional tumor-targeting drug integrating tumor imaging diagnosis and photothermal-immunotherapy, and has great guiding significance for the diagnosis and treatment of clinical PD-L1-positive tumor patients.

Successful treatment of non-melanoma skin cancer in three patients with Xeroderma Pigmentosum by modified ALA-PDT.

Xeroderma pigmentosum(XP) is a rare autosomal recessive genodermatosis. Individuals with XP are characterized by severe skin sensitivity to sunlight, and more susceptible to the development of skin malignancies in sun-exposed regions. We report the experience of modified 5-aminolaevulinic acid photodynamic therapy (M-PDT) in the treatment of three children with XP. They all developed multiple freckle-like hyperpigmented papules and plaques on the face from an early age. Multiple cutaneous squamous cell carcinoma (cSCC) and actinic keratosis (AK) were developed in case 1 and case 2, and basal cell carcinoma (BCC) was observed in case 3. Sanger sequencing of targeted gene identified that case 1 and case 3 carried compound heterozygous mutations, and case 2 carried a homozygous mutation in the XPC gene. After multiple courses of M-PDT, the lesions were removed with mild adverse reactions, nearly painless and satisfactory safety.

Local narrow margin excision sequential with modified ALA-PDT for successful treatment of an 86-year-old patient with malignant proliferating trichilemmal tumor.

Malignant proliferating trichilemmal tumor (MPTT) is thought to represent the malignant counterpart of benign proliferative pilar cyst, a lesion originating from the outer hair root sheath. We report a case of an 86-year-old woman with an exophytic nodule containing an ulcerated surface in the temporal region. Histopathologically confirmed MPTT without metastasis, and considering the risk of metastasis and recurrence, we used single local narrow margin excision combined with modified 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT). No recurrence of skin lesions was found in the 2-year follow-up after combined therapy. In conclusion, local narrow margin excision sequential with modified ALA-PDT may be a particularly promising and effective treatment option for MPTT.