Icotinib hydrochloride enhances chemo- and radiosensitivity by inhibiting EGFR signaling and attenuating RAD51 expression and function in Hela S3 cells

Efficacy and safety of anti-angiogenesis agents combined with chemoradiotherapy in the treatment of locally advanced cervical cancer: a meta-analysis of randomized controlled trials

BACKGROUND

Neovascularization is an important factor causing radiotherapy resistance, tumor growth, and metastasis. It may provides a new direction for treatment of cervical cancer.

OBJECTIVE AND METHODS

The main objective is to systematically evaluate the clinical efficacy and safety of antiangiogenic therapy combined with CCRT in the treatment of cervical cancer. We searched major Chinese and English databases to collect relevant studies from the database establishment up to April 2022. The experimental group of the studies included used CCRT combined with anti-angiogenic therapy, while another used only CCRT. We used the 'Cochrane Collaboration's tool' to assess risk of bias and RevMan 5.4 to conduct analysis.

RESULTS

Twelve studies with 793 patients were included. Use clinical efficiency and adverse reactions as effect indicators. It showed that the combination can improve the ORR (OR = 3.52, P < 0.00001), CR(OR = 2.46, P < 0.00001), DCR (OR = 2.64, P= 0.005), and OS(HR = 0.56, P = 0.03). But it increases the risk of neutropenia (OR = 1.86, P = 0.004) and hypertension (OR = 5.57, P = 0.003).

CONCLUSIONS

Combined therapy can improve the clinical efficacy of cervical cancer, but the safety needs to be considered.

Recent progress of the tumor microenvironmental metabolism in cervical cancer radioresistance

Radiotherapy is widely used as an indispensable treatment option for cervical cancer patients. However, radioresistance always occurs and has become a big obstacle to treatment efficacy. The reason for radioresistance is mainly attributed to the high repair ability of tumor cells that overcome the DNA damage caused by radiotherapy, and the increased self-healing ability of cancer stem cells (CSCs). Accumulating findings have demonstrated that the tumor microenvironment (TME) is closely related to cervical cancer radioresistance in many aspects, especially in the metabolic processes. In this review, we discuss radiotherapy in cervical cancer radioresistance, and focus on recent research progress of the TME metabolism that affects radioresistance in cervical cancer. Understanding the mechanism of metabolism in cervical cancer radioresistance may help identify useful therapeutic targets for developing novel therapy, overcome radioresistance and improve the efficacy of radiotherapy in clinics and quality of life of patients.

Relationships between DNA repair and RTK-mediated signaling pathways

Receptor Tyrosine Kinases (RTK) are an important family involved in numerous signaling pathways essential for proliferation, cell survival, transcription or cell-cycle regulation. Their role and involvement in cancer cell survival have been widely described in the literature, and are generally associated with overexpression and/or excessive activity in the cancer pathology. Because of these characteristics, RTKs are relevant targets in the fight against cancer. In the last decade, increasingly numerous works describe the role of RTK signaling in the modulation of DNA repair, thus providing evidence of the relationship between RTKs and the protein actors in the repair pathways. In this review, we propose a summary of RTKs described as potential modulators of double-stranded DNA repair pathways in order to put forward new lines of research aimed at the implementation of new therapeutic strategies targeting both DNA repair pathways and RTK-mediated signaling pathways.

The Combination of Icotinib Hydrochloride and Fluzoparib Enhances the Radiosensitivity of Biliary Tract Cancer Cells

Background

Radiotherapy and chemotherapy are the main clinical treatments for biliary tract cancers (BTCs). Patients with advanced disease have a very poor prognosis, yet no molecular targets have been proven effective for the adjuvant therapy of BTCs. In this study, we aimed to explore the effect of combination treatment with icotinib hydrochloride (IH) and fluzoparib (FZ) on radiosensitivity and clarify its underlying mechanism in the HCCC-9810 and GBC-SD human BTC cell lines.

Methods

Cell proliferation was measured by Cell Counting Kit-8 (CCK-8) assay. The cell cycle distribution and apoptosis were analyzed by flow cytometry. The phosphorylation of EGFR and its downstream signaling molecules and the expression of RAD51 were measured by Western blot analysis. γ-H2AX foci in the cellular nuclei were visualized using immunofluorescence staining. A colony formation assay was performed to demonstrate cell radiosensitivity with IH and FZ combination treatment.

Results

In the HCCC-9810 and GBC-SD human BTC cell lines, combined treatment with IH and FZ with synergetic radiation significantly inhibited cell proliferation, redistributed the cell cycle, enhanced apoptosis and delayed DNA damage repair by suppressing activation of the EGFR signaling pathway and attenuating expression of the homologous recombination (HR) protein RAD51.

Conclusion

This study demonstrates that combined treatment with IH and FZ may be an applicable therapy to enhance the radiosensitivity of BTCs and that RAD51 may serve as a biomarker for this combination treatment.

Chalcomoracin inhibits cell proliferation and increases sensitivity to radiotherapy in human non-small cell lung cancer cells via inducing endoplasmic reticulum stress-mediated paraptosis

Chalcomoracin (CMR) is a kind of Diels–Alder adduct extracted from the mulberry leaves. Recent studies showed that CMR has a broad spectrum of anticancer activities and induces paraptosis in breast cancer and prostate cancer cells. In this study, we investigated the effects of CMR against human non-small cell lung cancer cells and the underlying mechanisms. We found that CMR dose-dependently inhibited the proliferation of human lung cancer H460, A549 and PC-9 cells. Furthermore, exposure to low and median doses of CMR induced paraptosis but not apoptosis, which was presented as the formation of extensive cytoplasmic vacuolation with increased expression of endoplasmic reticulum stress markers, Bip and Chop, as well as activation of MAPK pathway in the lung cancer cells. Knockdown of Bip with siRNA not only reduced the cell-killing effect of CMR, but also decreased the percentage of cytoplasmic vacuoles in H460 cells. Moreover, CMR also increased the sensitivity of lung cancer cells to radiotherapy through enhanced endoplasmic reticulum stress. In lung cancer H460 cell xenograft nude mice, combined treatment of CMR and radiation caused greatly enhanced tumor growth inhibition with upregulation of endoplasmic reticulum stress proteins and activation of pErk in xenograft tumor tissue. These data demonstrate that the anticancer activity and radiosensitization effect of CMR result from inducing paraptosis, suggesting that CMR could be considered as a potential anticancer agent and radiation sensitizer in the future cancer therapeutics.

Cytogenetic and Transcriptomic Analysis of Human Endometrial MSC Retaining Proliferative Activity after Sublethal Heat Shock

Temperature is an important exogenous factor capable of leading to irreversible processes in the vital activity of cells. However, the long-term effects of heat shock (HS) on mesenchymal stromal cells (MSC) remain unstudied. We investigated the karyotype and DNA repair drivers and pathways in the human endometrium MSC (eMSC) survived progeny at passage 6 after sublethal heat stress (sublethal heat stress survived progeny (SHS-SP)). G-banding revealed an outbreak of random karyotype instability caused by chromosome breakages and aneuploidy. Molecular karyotyping confirmed the random nature of this instability. Transcriptome analysis found homologous recombination (HR) deficiency that most likely originated from the low thermostability of the AT-rich HR driving genes. SHS-SP protection from transformation is provided presumably by low oncogene expression maintained by tight co-regulation between thermosensitive HR drivers BRCA, ATM, ATR, and RAD51 (decreasing expression after SHS), and oncogenes mTOR, MDM2, KRAS, and EGFR. The cancer-related transcriptomic features previously identified in hTERT transformed MSC in culture were not found in SHS-SP, suggesting no traits of malignancy in them. The entrance of SHS-SP into replicative senescence after 25 passages confirms their mortality and absence of transformation features. Overall, our data indicate that SHS may trigger non-tumorigenic karyotypic instability due to HR deficiency and decrease of oncogene expression in progeny of SHS-survived MSC. These data can be helpful for the development of new therapeutic approaches in personalized medicine.