Search

Abstract Background Mesenchymal stem cells (MSCs) have been considered to be the attractive vehicles for delivering therapeutic agents toward various tumor diseases. This study was to explore the distribution pattern, kinetic delivery of adenovirus, and therapeutic efficacy of the MSC loading of E1A mutant conditionally replicative adenovirus Adv-Stat3(-) which selectively replicated and expressed high levels of anti-sense Stat3 complementary DNA in breast cancer and melanoma cells. Methods We assessed the release ability of conditionally replicative adenovirus (CRAd) from MSC using crystal violet staining, TCID50 assay, and quantitative PCR. In vitro killing competence of MSCs carrying Adv-Stat3(-) toward breast cancer and melanoma was performed using co-culture system of transwell plates. We examined tumor tropism of MSC by Prussian blue staining and immunofluorescence. In vivo killing competence of MSCs carrying Adv-Stat3(-) toward breast tumor was analyzed by comparison of tumor volumes and survival periods. Results Adv-Stat3(-) amplified in MSCs and were released 4 days after infection. MSCs carrying Adv-Stat3(-) caused viral amplification, depletion of Stat3 and its downstream proteins, and led to significant apoptosis in breast cancer and melanoma cell lines. In vivo experiments confirmed the preferential localization of MSCs in the tumor periphery 24 hours after tail vein injection, and this localization was mainly detected in the tumor parenchyma after 72 hours. Intravenous injection of MSCs carrying Adv-Stat3(-) suppressed the Stat3 pathway, down-regulated Ki67 expression, and recruited CD11b-positive cells in the local tumor, inhibiting tumor growth and increasing the survival of tumor-bearing mice. Conclusions These results indicate that MSCs migrate to the tumor site in a time-dependent manner and could be an effective platform for the targeted delivery of CRAd and the amplification of tumor killing effects.

Abstract Background P21(WAF1/Cip1) binds to cyclin-dependent kinase complexes and inhibits their activities. It was originally described as an inhibitor of cancer cell proliferation. However, many recent studies have shown that p21 promotes tumor progression when accumulated in the cell cytoplasm. So far, little is known about the correlation between cytoplasmic p21 and drug resistance. This study was aimed to investigate the role of p21 in the cisplatin resistance of ovarian cancer. Methods RT-PCR, western blot and immunofluorescence were used to detect p21 expression and location in cisplatin-resistant ovarian cancer cell line C13* and its parental line OV2008. Regulation of cytoplasmic p21 was performed through transfection of p21 siRNA, Akt2 shRNA and Akt2 constitutively active vector in the two cell lines; their effects on cisplatin-induced apoptosis were evaluated by flow cytometry. Tumor tissue sections of clinical samples were analyzed by immunohistochemistry. Results p21 predominantly localizes to the cytoplasm in C13* compared to OV2008. Persistent exposure to low dose cisplatin in OV2008 leads to p21 translocation from nuclear to cytoplasm, while it had not impact on p21 localization in C13*. Knockdown of cytoplasmic p21 by p21 siRNA transfection in C13* notably increased cisplatin-induced apoptosis through activation of caspase 3. Inhibition of p21 translocation into the cytoplasm by transfection of Akt2 shRNA into C13* cells significantly increased cisplatin-induced apoptosis, while induction of p21 translocation into the cytoplasm by transfection of constitutively active Akt2 in OV2008 enhanced the resistance to cisplatin. Immunohistochemical analysis of clinical ovarian tumor tissues demonstrated that cytoplasmic p21 was negatively correlated with the response to cisplatin based treatment. Conclusions Cytoplasmic p21 is a novel biomarker of cisplatin resistance and it may represent a potential therapeutic target for ovarian tumors that are refractory to conventional treatment.

Introduction: The management of patients with low-grade cervical intraepithelial neoplasia (CIN1) remains controversial. We analyzed the pathological upgrading rates of patients with CIN1 undergoing conization, identifying influencing factors, and compared their outcomes to those of patients with CIN1 receiving follow-up only., Methods: This retrospective study included 466 patients with CIN1 confirmed by histopathology and treated with conization. Postoperative pathological upgrading was determined and its influencing factors were identified. We also analyzed post-conization outcomes, examining the rate of persistent/recurrent CIN1 and its influencing factors, and comparing these results to those of patients receiving follow-up only., Results: The pathological upgrading rate of patients with CIN1 after conization was 21.03% (98/466), and the influencing factors were preoperative high-risk human papillomavirus (HR-HPV) infection and cytological results. The upgrading rates of HR-HPV positive and negative patients were 22.05% and 0.00%, respectively ( χ 2 = 5.03, P =0.03). The upgrading rate of patients with cytological results negative for intraepithelial lesion malignancy was 10.94%, while the upgrading rates of atypical squamous cells, cannot exclude high-grade lesion(ASC-H) and high-grade squamous intraepithelial lesion(HSIL) groups were 47.37% and 52.94%, respectively ( χ 2 = 22.7, P =0.03). Persistent/recurrent CIN1 rates in the conization group were 21.24%, 15.97%, and 6.67% at 6, 12, and 24 months, respectively, significantly lower than those in the follow-up only group. The CIN2 progression rate in the conization group (0.26%) during the 24-month follow-up period was also significantly lower than that in the follow-up only group (15.15%; χ 2 = 51.68, P <0.01). The only factor influencing postoperative persistent/recurrent CIN1 was preoperative HR-HPV status. No patients who were HR-HPV negative preoperatively exhibited persistent/recurrent CIN1, compared with 25.55% of those who were HR-HPV positive preoperatively ( χ 2 = 4.40, P =0.04)., Discussion: The risk of progression to CIN2+ in the medium term is higher in patients with CIN1 receiving follow-up than in those undergoing conization. Doctors should refer to the guidelines but comprehensively consider age, fertility requirements, preoperative HR-HPV and cytological results, follow-up conditions, and other factors to select the most appropriate treatment strategy for patients with CIN1., Competing Interests: The authors declare that the research was conducted without any commercial or financial relationships that could be construed as potential conflicts of interest., (Copyright © 2024 Guo, Cai, Peng, Wang, Li, Zou, Guo, Wang, Wu and Ma.)

Patients with irreversible hypothyroidism require lifelong levo-thyroxin ( L-T4) replacement therapy, which makes them feel discomfortable. With the development of the thyroid tissues autotransplantation and embryonic stem cell (ESC), this would be a more physiological approach to the treatment of irreversible hypothyroidism. The animal experiments and human clinical trials on thyroid tissues autotransplantation have shown that the autograft can survive and function. The advanced researches have demonstrated that ESC can differentiate into thyroid follicular cells.