Metformin relieves bone cancer pain by reducing TGFßRI-TRPV1 signaling in rats.

Common cancer complications include bone cancer pain (BCP), which was not sufficiently alleviated by traditional analgesics. More safe and effective therapy was urgent needed. Metformin relieved osteoarthritis pain, but the analgesia of Metformin in BCP was not well studied. The study aimed to explore the Metformin-mediated analgesic effect and its molecular mechanisms in BCP rats. We demonstrated that Walker 256 cell transplantation into the medullary cavity of the tibia worsened mechanical allodynia in BCP rats, increased the expression of TGFß1 in the metastatic bone tissue, and raised the expression of TGFßRI and TRPV1 in the L4-6 dorsal root ganglion (DRG) of BCP rats. While, selectively blockade of TGFßRI by SD208 could obviously elevated the paw withdraw threshold (PWT) of BCP rats, together with decreased TRPV1 expression in L4-6 DRG. Notably, continuous Metformin treatment reduced TGFß1, TGFßRI and TRPV1 expression, and relieved mechanical allodynia of BCP rats in a long-term effect. In conclusion, these results illustrated that Metformin ameliorated bone cancer pain, and the downregulation of TGFß1-TGFßRI-TRPV1 might be a potential mechanism of Metformin-mediated analgesia in BCP.

Folic acid relieves bone cancer pain by downregulating P2X2/3 receptors in rats.

BACKGROUND: Bone cancer pain (BCP) remains a clinical challenge due to the limited and side effects of therapeutic methods. Folic acid has been known as an FDA approved dietary supplement and proved to have an analgesic effect in neuropathic pain. Here we investigate the role and mechanism of folic acid in bone cancer pain of a rat model. METHODS: Walker 256 tumor cells were inoculated into the left tibia of rats to induce bone cancer pain model. Pain reflex were assessed by paw withdrawal threshold (PWT) response to Von Frey filaments and paw withdrawal latency (PWL) response to thermal stimulation. Folic acid was injected intraperitoneally to evaluate its analgesic effect in rats with bone cancer pain. Western blotting and qPCR were used to determine P2X2/3 receptor protein and mRNA levels in ipsilateral L4-6 dorsal root ganglion (DRG) and spinal dorsal horn (SDH). RESULTS: The PWT and PWL of rats with bone cancer pain were obviously decreased compared to the naïve and sham rats. Interestingly, continuous folic acid treatment significantly increased the PWT and PWL of rats with bone cancer pain. P2X2 and P2X3 receptors were clearly upregulated at both mRNA and protein expression in L4-6 DRG and SDH of rats with bone cancer pain. P2X2 and P2X3 receptors were mainly localized with CGRP (calcitonin gene-related peptide) or IB4 (isolectin B4) positive neurons in L4-6 DRG of rats with bone cancer pain. Notably, continuous folic acid treatment significantly reduced the expression of P2X2 and P2X3 receptors in L4-6 DRG and SDH of rats with bone cancer pain. Finally, intrathecal injection of A317491 (a selective antagonist of P2X2/3 receptors) markedly elevated the PWT and PWL of rats with bone cancer pain. CONCLUSION: These results suggest that folic acid has an effective antinociceptive effect on bone cancer pain, which is mediated by downregulating P2X2/3 receptors in L4-6 DRG and SDH of rats with bone cancer pain. Folic acid may be a novel therapeutic strategy in cancer patients for pain relief.

Antitumor Effect of Demethylzeylasteral (T-96) on Triple-Negative Breast Cancer via LSD1-Mediate Epigenetic Mechanisms.

Background and Purpose. Breast cancer ranks first in the incidence of female tumors. Triple-negative breast cancer (TNBC), one type of breast cancer, is more aggressive and has a worse prognosis. Demethylzeylasteral (T-96) is isolated from Tripterygium wilfordii Hook F. Our previous study found that T96 could inhibit TNBC invasion via suppressing the canonical and noncanonical TGF-ß signaling pathways. However, the antitumor effects and mechanisms of T-96 on TNBC have not been studied. This study is aimed at investigating the antitumor effect and mechanism of T-96 on breast cancer. Experimental approach. MTT assay, Live and Dead cell assay, and TUNEL were used to observe the antitumor effect of breast cancer cells treated with T-96. siRNA of LSD1, Co-IP, and molecular docking were used to explore the direct target and mechanism of T-96. Subcutaneous murine xenograft models were used to detect the efficacy of T-96 antitumor activity in vivo. Key Results. T-96 was more susceptible to inducing the apoptosis of highly metastatic TNBC cell lines (SUM-1315). An abnormal level of histone methylation is a crucial characteristic of metastatic cancer cells. LSD1 is a histone demethylase. We found that T-96 could significantly decrease the protein expression of LSD1, increase its target protein PTEN expression and enhance histone methylation. T-96 could also down-regulate the PI3K/AKT signaling pathway, which could be blocked by PTEN. Knockdown of LSD1 by siRNA blocked the pharmacological activity of T-96. And the molecular docking predicted T-96 processed affinity toward LSD1 through hydrogen bonding. Finally, T-96 was evaluated in a murine xenograft model of SUM-1315 cells. And T-96 could significantly inhibit tumor growth without showing marked toxicity. Conclusions & Implications. The results illustrated that T-96 exerted antitumor activity in highly metastatic TNBC by inactivating the LSD1 function.

Berberine inhibits the proliferation, invasion and migration of endometrial stromal cells by downregulating miR­429.

Endometriosis (EM) is a common gynecological disease, and its pathological process is accompanied by the migration and proliferation of uterine cells. Berberine (BBR) has been shown to exhibit antitumor activity; however, the effects of BBR on EM have seldom been reported to date. The expression of microRNA (miR)­429 is upregulated in EM and miR­429 can be used as a target for drug regulation of cancer cells. Whether BBR plays a regulatory role in EM by targeting miR­429 has not been reported. Thus, the aim of the present study was to determine the effects of BBR on EM cells. The survival rate of immortalized human endometrial stromal cells (HESCs) was determined using a Cell Counting Kit­8 assay. A colony formation assay was used to detect the rate of cell proliferation. The expression levels of proliferation­related proteins, including proliferation marker protein Ki­67 (Ki­67) and proliferating cell nuclear antigen (PCNA), were detected by reverse transcription­quantitative PCR (RT­qPCR) and western blotting. Wound healing and Transwell assays were performed to detect cell migration and invasion, and western blotting was used to detect the expression of the migration­ and invasion­related proteins, including matrix metalloproteinase (MMP)2, MMP4 and MMP9. The expression of miR­429 was detected by RT­qPCR following its overexpression via cell transfection. The results revealed that treatment with 80 µM BBR significantly inhibited cell proliferation and colony formation, and inhibited the expression of Ki­67 and PCNA proteins in HESCs. BBR inhibited cell invasion and migration, as well as the expression of MMP2, MMP4 and MMP9. In this process, it was found that the expression of miR­429 decreased following treatment of the cells with BBR, whereas the inhibitory effects of BBR on cell proliferation, invasion and migration were suppressed following the overexpression of miR­429. Overall, the findings of the present study indicated that BBR inhibited the proliferation, invasion and migration of HESCs by downregulating the expression of miR­429.

Clinicopathological significance of PI3K, Akt and survivin expression in gastric cancer.

BACKGROUND: Gastric cancer is the second leading cause of cancer-related deaths worldwide, and is characterized by invasion and metastasis. Increasing attention is being focused on discovering molecular markers for diagnosis and prognosis. Our objective was to evaluate PI3K, Akt and survivin protein expression in gastric cancer, and their correlations with clinicohistological features and prognosis in patients with gastric cancer. METHODS: Tissue samples were obtained from 70 patients with gastric cancer patients and 20 patients with normal gastric mucosa. The protein levels of PI3K, Akt and survivin were evaluated by immunohistochemistry. Statistical analyses were performed to establish the correlations between their expressions and patients' clinicopathologic characteristics. RESULTS: The positive expression rates of PI3K, Akt and survivin were significantly higher in the gastric cancer tissues compared to normal gastric mucosa (P<0.05). Expression levels of PI3K, Akt and survivin proteins were significantly correlated with TNM stage, differentiation grade, lymph node metastasis and metastases to other organs (P<0.05). Cooperative relationships were identified between PI3K and Akt, and PI3K and survivin (P<0.01), suggesting the involvement of the PI3K/Akt/survivin signaling pathway in the tumorigenesis of gastric cancer. CONCLUSIONS: Protein expression of PI3K, Akt and survivin were significantly associated with the development, progression and metastasis of gastric cancer and may have value as diagnostic and prognostic markers in gastric cancer.