Emerging Drug Delivery Vectors: Engineering of Plant-Derived Nanovesicles and Their Applications in Biomedicine

Extracellular vesicles can transmit intercellular information and transport biomolecules to recipient cells during various pathophysiological processes in the organism. Animal cell exosomes have been identified as potential nanodrugs delivery vehicles, yet they have some shortcomings such as high immunogenicity, high cytotoxicity, and complicated preparation procedures. In addition to exosomes, plant-derived extracellular vesicles (PDVs), which carry a variety of active substances, are another promising nano-transport vehicles emerging in recent years due to their stable physicochemical properties, wide source, and low cost. This work briefly introduces the collection and characterization of PDVs, then focuses on the application of PDVs as natural or engineered drug carriers in biomedicine, and finally discusses the development and challenges of PDVs in future applications.

Integration of Multiparameter MRI into Conventional Pretreatment Risk Factors to Predict Adverse Features after Radical Prostatectomy

PURPOSE/OBJECTIVE(S)

The purpose of this study was to Integration of Multiparameter MRI into conventional pretreatment risk factors to develop nomogram for the prediction of adverse features (i.e., positive margin (PM) or extra-prostatic extension (EPE)) indicated for postoperative radiotherapy in patients with prostate cancer.

MATERIALS/METHODS

We analyzed 203 histologically proven prostate cancer patients underwent preoperative 3T multiparametric MRI including high b value (0, 1500 s/mm2) diffusion-weighted imaging between 2019 and 2022 at our hospital. Patients with a history of neoadjuvant hormonal therapy, or patients whose surgeon's experience was ≤3 years were excluded. Age, surgical technique, serum PSA level, PSA density, clinical T stage, and biopsy Gleason score were clinical predictors. MRI parameters include prostate volume, tumor size, ECE score, seminal vesicle invasion score, tumor location (apex, peripheral region, or bladder neck), apparent diffusion coefficient (ADC), tumor contact length (TCL), PI-RADS score. Predictors were used in nomograms developed from multivariable logistic regression analysis to estimate the probability of positive margin (PM) or extra-prostatic extension (EPE) after RP. The nomogram's predictive accuracy and discriminative ability were determined by the concordance index with calibration and receiver operating characteristic (ROC) curves.

RESULTS

(1) Patient characters: Table 1 lists the MRI characteristics of the patients. Median PSA level is 17.6ng/ml. All patients received extra-fascial resection. 44% of the patients underwent robotic surgery. 24% of the patients had positive margins. In 226 patients who was clinically confined to the prostate, 100 (44%) had a postoperative pathological upgrade of pT3a or above. 46 (29%) of the 158 patients with biopsy grade group (GG)1 was confirmed GG3-5 after RP.

CONCLUSION

Using mpMRI parameters and clinicopathological information, we produced nomograms that may accurately predict adverse Features that are indications for postoperative radiotherapy after RP, which may help individualize treatment decision-making.

Safety and Efficacy of Radiotherapy Combined with Chemotherapy for Recurrent Metastatic Renal Pelvic and Ureteral Carcinoma

PURPOSE/OBJECTIVE(S)

To retrospectively investigate the safety and efficacy of radiotherapy combined with systemic chemotherapy for recurrent metastatic renal pelvic and ureteral carcinoma.

MATERIALS/METHODS

A total of 109 patients were enrolled in this study, including 44 patients in the Radio-chemotherapy group and 65 patients in the Chemotherapy group. Propensity score matching (PSM) was used to balance the clinical baseline characteristics of the two groups by 1:1 matching. Kaplan-Meier method was used to calculate progression-free survival (PFS) and overall survival (OS) before and after matching. Prognostic factors were analyzed by Cox proportional risk model. Treatment-related adverse events were graded according to the Common Terminology Criteria for Adverse Events (CTCAE), version 5.0.

RESULTS

The median follow-up time was 14.5 months. Multivariate analysis showed that radiotherapy was a good independent prognostic factor for OS in patients with recurrent metastatic renal pelvic and ureteral carcinoma (HR: 0.327, 95% CI: 0.157∼0.680, P = 0.003). After matching, there were 40 patients in the Radio-chemotherapy group and 40 patients in the Chemotherapy group, and the median PFS and median OS in the Radio-chemotherapy group were better than those in the Chemotherapy group (PFS: 10.4 months vs. 6.7 months, P = 0.035; OS: 43.5 months vs. 18.8 months, P<0.001). The 1-year OS and 2-year OS of the Radio-chemotherapy group were higher than those of the Chemotherapy group (1-year OS: 88.1% vs. 70.4%; 2-year OS: 81.1% vs. 39.3%). In addition, in the Radio-chemotherapy group, patients treated with radiotherapy before first-line chemotherapy failure had longer PFS than those treated with radiotherapy after chemotherapy failure (median PFS: 15.7 months vs. 6 months, P = 0.003). There was no significant difference in the incidence of grade 3∼4 toxicities between the Radio-chemotherapy group and the Chemotherapy group (52.3% vs. 50.8%, P = 0.878).

CONCLUSION

For patients with advanced renal pelvic and ureteral carcinoma, adding radiotherapy on the basis of systemic chemotherapy is well tolerable and expected to bring long-term survival benefits to patients, and the benefits of early interventional radiotherapy may be more obvious.

Effect of Adjuvant Chemotherapy in Highly Malignant Non-Metastatic Prostate Cancer: An Interim Analysis of Non-Randomized Comparative Trials

PURPOSE/OBJECTIVE(S)

Gleason grade group 5 (GG5) prostate cancers is aggressive with high metastatic rates and is not sensitive to androgen deprivation therapy (ADT). Even the presence of a limited (tertiary) Gleason pattern 5 component may have high aggressive biological behavior. This study aims to prospectively evaluate whether a non-androgen receptor pathway therapy - adjuvant chemotherapy could improve clinical outcomes among non-metastatic prostate cancer with the above highly malignant characters.

MATERIALS/METHODS

This prospective non-randomized clinical trial included non-metastatic prostate cancer patients with pathologically proven Gleason score of 9-10 or tertiary Gleason pattern 5. Each subject was allowed to decide whether to receive four to six cycles chemotherapy of docetaxel after receiving a standard treatment (i.e., radical surgery ± radiotherapy or radical radiotherapy combined with long-term ADT). The primary endpoint was event-free survival (EFS). Event was defined as any of biochemical failure or imaging failure, or change of systemic therapy due to PSA arises, or death. The secondary end points were distant metastasis-free survival (MFS), overall survival (OS), and treatment-related adverse events.

RESULTS

A total of 188 consecutive patients were enrolled from November 2019 to November 2022. Median prostate-specific antigen was 26.6 ng/ml. 52% had T3b to T4 disease, 27% had N1 disease. 140 patients received standard therapy only, and 48 patients received adjuvant chemotherapy after radical therapy. The median follow-up time was 18.4 (3.0-36.7) months. The estimated 36-month EFS of the chemotherapy group and the control group were 94.7% vs. 72.8% (p = 0.044). There were 1 event who added novel endocrine therapy in the chemotherapy group, and 21 events in the control group, including 6 cases of biochemical recurrence and 9 cases of lymph node and distant metastasis, 4 cases that changed systemic therapy and 2 cases died. The MFS of the two groups at 36 months were 100% and 90.7%, respectively (P = 0.143). After the 1:1 propensity score match, the EFS and MFS of the two groups were 94.7% and 80.8% (P = 0.069), and 100% and 93.1% (P = 0.132), respectively. The urinary toxicity of grade 2 and 3 in the chemotherapy group and the control group were 4.2% and 7.1% (P = 0.134) while the grade 2 rectal toxicity were 5.0% and 10.4% (P = 0.317), respectively. No grade 4 toxicity occurred. Considering the chemotherapy-related side effects, grade 3 or above toxicity were leukopenia (41.7%), alopecia (27.1%), thrombocytopenia (2.1%) and edema (2.1%).

CONCLUSION

Results of this interim analysis shows that the addition of adjuvant chemotherapy after standard radical therapy tends to improve the overall recurrence and metastasis free survival of patients with highly malignant prostate cancer, and the adverse effects are tolerable, which should be confirmed by long-term follow-up results.

Outcomes of Targeted Therapy Plus Immunotherapy and High-Dose Stereotactic Ablative Body Radiotherapy (SABR) for Metastatic Renal Cell Cancer Patients

PURPOSE/OBJECTIVE(S)

Stereotactic ablative body radiotherapy (SABR) is one of the treatment options for metastatic renal cell carcinoma (mRCC) but is limited by a lack of data to evaluate targeted therapy plus immunotherapy concurrently with high-dose SABR to multiple sites. We evaluated the safety and disease control for mRCC patients who concurrently received the above tri-modality treatment.

MATERIALS/METHODS

Patients were treated with SABR (40-70 Gy/5-10 fractions) for small lesions or partial-SABR (tumor center boosted with 6-8 Gy/3-5 fractions with 50-60 Gy/20-25 fractions to the whole tumor volume) for bulky tumors or tumors adjacent to critical organs. When SABR/partial-SABR was not feasible, a moderate fractionated radiotherapy plan, usually 60Gy/20 fractions were applied. of Targeted therapy plus immunotherapy (PD-1 inhibitor) was not interrupted during or after radiotherapy (RT). Adverse events (AEs) were evaluated. Disease control rate (DCR), objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were calculated. The PFS1 was defined as the first progression since the start of RT. The PFS2 was defined as the second progression after the second RT course, if new metastases occurred after first RT were all re-irradiated, and the systemic therapy was not changed. The Kaplan-Meier method was used for time-to-event endpoints.

RESULTS

A total of 51 patients, with a median age of 57 yr, were enrolled. The median follow-up was 12 months. There were 75% of patients with intermediate-risk and 18% with favorable-risk disease. 61% of the patients were oligometastatic. 71% had clear cell renal cancer. There were 241 metastases while 161 (67%) were irradiated. 80% of the lesions received SABRP/partial SABR. 1 patient with 14 lesions irradiated received proton therapy. All the surviving patients are continuing using targeted therapy while 81% patients complete at least 1-year PD-1 therapy. 10 patients (20%) had grade 3 drug-related AEs: pneumonitis (n = 2), elevated alanine transaminase (n = 4), myositis (n = 1), hand-foot syndrome myositis (n = 1), enteritis (n = 1), fatigue (n = 1). There were 1 grade 4 AEs of upper gastrointestinal bleeding. No grade 3-5 RT-related AEs was found. ORR and DCR for irradiated lesion were 51% and 98%. Median OS and PFS2 was not reached. Median PFS1 was 14(6-22) months. Estimated 1- and 2-yr OS, PFS1 and PFS2 were 90% and 90%, 56% and 38%, 74% and 51% respectively. Univariate analysis showed that an PFS1 benefit was found in patients who received radiation before systemic therapy failure (p = 0.038).

CONCLUSION

We investigated the high-dose RT in combination of concurrent targeted and immunotherapy in patients with metastatic RCC. We found that this treatment regimen was well tolerated, with good cancer control. Early use of high-dose RT to multi-lesions may improve PFS. Partial-SABR for bulky lesions close to critical organs could be safely and effectively applied under certain circumstances. These encouraging findings warrant further investigation.

A self-assembled nanoplatform based on Ag2S quantum dots and tellurium nanorods for combined chemo-photothermal therapy guided by H2O2-activated near-infrared-II fluorescence imaging

A nanoplatform based on Ag₂S quantum dots (QDs) and tellurium nanorods (TeNRs) was developed for combined chemo-photothermal therapy guided by H₂O₂-activated near-infrared (NIR)-II fluorescence imaging. Polypeptide PC₁₀AGRD-modified TeNRs and Ag₂S QDs were co-encapsulated in 4T1 cell membrane to prepare a nanoplatform (CCM@AT). Ag₂S QDs and TeNRs in the CCM@AT were used as a fluorescence probe and photosensitizer, and a chemotherapeutic prodrug and quenching agent to quench the fluorescence of Ag₂S QDs, respectively. After the CCM@AT was specifically targeted to the tumor site, the TeNRs were dissolved by the high concentration of H₂O₂ at the tumor site to light up the fluorescence of Ag₂S QDs for NIR-II fluorescence imaging. In addition, the generated toxic TeO₆^6- molecules decreased ATP production by selective cancer chemotherapy, which is beneficial for photothermal therapy. The elevated temperature due to photothermal therapy in turn promoted the chemical reaction in chemotherapy. In vitro and in vivo toxicity results showed that the CCM@AT possesses high biocompatibility. Compared to single photothermal therapy and chemotherapy, the synergistic chemo-photothermal therapy can effectively suppress the growth of 4T1 tumor. This all-in-one nanoplatform provides a boulevard for the combination therapy of tumors guided by NIR-II fluorescence imaging. STATEMENT OF SIGNIFICANCE: NIR-II fluorescence imaging shows the characteristics of low tissue absorption, reflection, and scattering, which can greatly reduce the influence of autofluorescence in vivo. However, the non-negligible effect of autofluorescence is still observed in fluorescence imaging in vivo. Therefore, there is an urgent need to develop a strategy of controlled release of fluorescence for accurate imaging and tumor therapy. Here, Ag₂S quantum dots (QDs) with NIR-II fluorescence emission and good photothermal conversion efficiency are used as a fluorescence probe and photosensitizer, and tellurium nanorods (TeNRs) are used as a chemotherapeutic prodrug and quenching agent to quench the fluorescence of Ag₂S QDs. This multiple nanoplatform provides an inspiration for the combination therapy of tumor guided by NIR-II fluorescence imaging.

Growth performance, meat quality and Fatty Acid metabolism response of growing meat rabbits to dietary linoleic Acid

An experiment was conducted to determine the effects of different amounts of dietary linoleic acid (LA) on growth performance, serum biochemical traits, meat quality, fatty acids composition of muscle and liver, acetyl-CoA carboxylase (ACC) and carnitine palmitoyl transferase 1 (CPT 1) mRNA expression in the liver of 9 wks old to 13 wks old growing meat rabbits. One hundred and fifty 9 wks old meat rabbits were allocated to individual cages and randomly divided into five groups. Animals in each group were fed with a diet with the following LA addition concentrations: 0, 3, 6, 9 and 12 g/kg diet (as-fed basis) and LA concentrations were 0.84, 1.21, 1.34, 1.61 and 1.80% in the diet, respectively. The results showed as follows: the dietary LA levels significantly affected muscle color of LL included a* and b* of experimental rabbits (p<0.05). The linear effect of LA on serum high density lipoprotein cholesterol was obtained (p = 0.0119). The saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) contents of LL decreased and the polyunsaturated fatty acids (PUFAs) content of LL increased with dietary LA increase (p<0.0001). The PUFA n-6 content and PUFA n-3 content in the LL was significantly affected by the dietary LA levels (p<0.01, p<0.05). The MUFAs content in the liver decreased and the PUFAs contents in the liver increased with dietary LA increase (p<0.0001). The PUFA n-6 content and the PUFA n-6/n-3 ratio in the liver increased and PUFA n-3 content in the liver decreased with dietary LA increase (p<0.01). The linear effect of LA on CPT 1 mRNA expression in the liver was obtained (p = 0.0081). In summary, dietary LA addition had significant effects on liver and muscle fatty acid composition (increased PUFAs) of 9 wks old to 13 wks old growing meat rabbits, but had little effects on growth performance, meat physical traits and mRNA expression of liver relative enzyme of experimental rabbits.