Christos Vallilas

Dr. Christos Vallilas

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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CVChristos Vallilas
Christos Vallilas
Panagiotis SarantisPanagiotis Sarantis
Panagiotis Sarantis
AKANASTASIOS KYRIAZOGLOU
ANASTASIOS KYRIAZOGLOU
Evangelos KoustasEvangelos Koustas
Evangelos Koustas
Stamatios TheocharisStamatios Theocharis
Stamatios Theocharis
Michalis V KaramouzisMichalis V Karamouzis
Michalis V Karamouzis
Gastrointestinal stromal tumors (GISTs) are the most common types of malignant mesenchymal tumors in the gastrointestinal tract, with an estimated incidence of 1.5/100.000 per year and 1–2% of gastrointestinal neoplasms. About 75–80% of patients have mutations in the KIT gene in exons 9, 11, 13, 14, 17, and 5–10% of patients have mutations in the platelet-derived growth factor receptor a (PDGFRA) gene in exons 12, 14, 18. Moreover, 10–15% of patients have no mutations and are classified as wild type GIST. The treatment for metastatic or unresectable GISTs includes imatinib, sunitinib, and regorafenib. So far, GIST therapies have raised great expectations and offered patients a better quality of life, but increased pharmacological resistance to tyrosine kinase inhibitors is often observed. New treatment options have emerged, with ripretinib, avapritinib, and cabozantinib getting approvals for these tumors. Nowadays, immune checkpoint inhibitors form a new landscape in cancer therapeutics and have already shown remarkable responses in various tumors. Studies in melanoma, non-small-cell lung cancer, and renal cell carcinoma are very encouraging as these inhibitors have increased survival rates. The purpose of this review is to present alternative approaches for the treatment of the GIST patients, such as combinations of immunotherapy and novel inhibitors with traditional therapies (tyrosine kinase inhibitors).

27 November 2021 in Life
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Evangelos KoustasEvangelos Koustas
Evangelos Koustas
ETEleni-Myrto Trifylli
Eleni-Myrto Trifylli
Panagiotis SarantisPanagiotis Sarantis
Panagiotis Sarantis
NKNikolaos I. Kontolatis
Nikolaos I. Kontolatis
Christos DamaskosChristos Damaskos
Christos Damaskos
Michalis V KaramouzisMichalis V Karamouzis
Michalis V Karamouzis
Gastric cancer is the fifth most common malignancy and the third leading cause of cancer-related death worldwide. The three entirely variable entities have distinct epidemiology, molecular characteristics, prognosis, and strategies for clinical management. However, many gastric tumors appear to be resistant to current chemotherapeutic agents. Moreover, a significant number of gastric cancer patients, with a lack of optimal treatment strategies, have reduced survival. In recent years, multiple research data have highlighted the importance of autophagy, an essential catabolic process of cytoplasmic component digestion, in cancer. The role of autophagy as a tumor suppressor or tumor promoter mechanism remains controversial. The multistep nature of the autophagy process offers a wide array of targetable points for designing novel chemotherapeutic strategies. The purpose of this review is to summarize the current knowledge regarding the interplay between gastric cancer development and the autophagy process and decipher the role of autophagy in this kind of cancer. A plethora of different agents that direct or indirect target autophagy may be a novel therapeutic approach for gastric cancer patients.

13 October 2023 in Pharmaceutics
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Stavros P. PapadakosStavros P. Papadakos
Stavros P. Papadakos
Konstantinos ArvanitakisKonstantinos Arvanitakis
Konstantinos Arvanitakis
ISIoanna STERGIOU
Ioanna STERGIOU
CVChristos Vallilas
Christos Vallilas
SSStavros Sougioultzis
Stavros Sougioultzis
Stamatios TheocharisStamatios Theocharis
Stamatios Theocharis
Hepatocellular carcinoma (HCC) stands as a significant contributor to global cancer-related mortality. Chronic inflammation, often arising from diverse sources such as viral hepatitis, alcohol misuse, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH), profoundly influences HCC development. Within this context, the interplay of extracellular vesicles (EVs) gains prominence. EVs, encompassing exosomes and microvesicles, mediate cell-to-cell communication and cargo transfer, impacting various biological processes, including inflammation and cancer progression. Toll-like receptor 4 (TLR4), a key sentinel of the innate immune system, recognizes both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), thereby triggering diverse signaling cascades and pro-inflammatory cytokine release. The intricate involvement of the TLR4 signaling pathway in chronic liver disease and HCC pathogenesis is discussed in this study. Moreover, we delve into the therapeutic potential of modulating the TLR4 pathway using EVs as novel therapeutic agents for HCC. This review underscores the multifaceted role of EVs in the context of HCC and proposes innovative avenues for targeted interventions against this formidable disease.

9 June 2021 in Cancers
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Michalis V KaramouzisMichalis V Karamouzis
Michalis V Karamouzis
IAIlias Athanasiadis
Ilias Athanasiadis
GSGeorgios Samelis
Georgios Samelis
CVChristos Vallilas
Christos Vallilas
ABAlexandros Bokas
Alexandros Bokas
PPPavlos Papakotoulas
Pavlos Papakotoulas
Pancreatic cancer (PaC) induces a prothrombotic and hypercoagulable state. The aim of this study was to investigate the effect of tinzaparin in combination with chemotherapy. The PaCT (pancreatic cancer and tinzaparin) study was a retrospective observational study that collected data regarding progression free survival (PFS) in advanced or metastatic PaC patients who received thromboprophylaxis with tinzaparin during chemotherapy with nab-paclitaxel (N) and gemcitabine (G). The primary end point was to compare, from already published data, the PFS of patients receiving thromboprophylaxis with tinzaparin with the PFS of patients receiving chemotherapy with N–G but no thromboprophylaxis. Secondary end points were efficacy and safety of anticoagulation. In total, 110 PaC patients, 93% with advanced or metastatic disease, treated with N–G and tinzaparin (10,291 ± 1176 Anti-Xa IU, OD, median duration 8.7, IQR: 5.6–11.9 months) were enrolled. Of these, 52% were males and; the median age was 68 (40–86 years). The tumor was located to in the pancreatic head at in 45% of the patients. The median PFS was 7.9 months (IQR: 5.0–11.8 months). Out of 14 similar studies (involving 2994 patients) identified via systematic search, it was determined that the weighted PFS of patients receiving N–G but no anticoagulation was 5.6 months. Therefore, patients receiving tinzaparin had 39.54% higher PFS than patients without thromboprophylaxis (p < 0.05). During the follow-up period of 18.3 ± 11.7 months, three (2.7%) thrombotic events were recorded while two clinically relevant non-major bleeding events occurred (1.9%). In conclusion, PFS in advanced PaC patients undergoing chemotherapy is positively impacted by anticoagulation. Thromboprophylaxis with tinzaparin in treatment dose is efficient and safe.

Verified
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Christos DamaskosChristos Damaskos
Christos Damaskos
Nikolaos GarmpisNikolaos Garmpis
Nikolaos Garmpis
DDDimitrios Dimitroulis
Dimitrios Dimitroulis
AGANNA GARMPI
ANNA GARMPI
EDEvangelos Diamantis
Evangelos Diamantis
GKGregory Kouraklis
Gregory Kouraklis
Long non-coding RNAs (lncRNAs) are transcripts of more than 200 nucleotides which cannot be translated into proteins. Small nucleolar RNA host gene 15 (SNHG15) is a lncRNA whose dysregulation has been found to have an important impact on carcinogenesis and affect the prognosis of cancer patients in various cancer types. Hepatocellular carcinoma (HCC) is one of the most common cancers with a poor long-term prognosis, while the best prognostic factor of the disease is its early diagnosis and surgery. Consequently, the investigation of the mechanisms of hepatocarcinogenesis, as well as the discovery of efficient molecular markers and therapeutic targets are of great significance. An extensive literature search was performed in MEDLINE in order to identify clinical studies that tried to reveal the role of SNHG15 in HCC. We used keywords such as ‘HCC’, ‘hepatocellular carcinoma’, ‘SNHG15’ and ‘clinical study’. Finally, we included four studies written in English, published during the period 2016–2021. It was revealed that SNHG15 is related to the appearance of HCC via different routes and its over-expression affects the overall survival of the patients. More assays are required in order to clarify the potential role of SNHG15 as a prognostic tool and therapeutic target in HCC.

15 December 2020 in Cancers
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AKAnna Koumarianou
Anna Koumarianou
ANAnastasios Ntavatzikos
Anastasios Ntavatzikos
CVChristos Vallilas
Christos Vallilas
KKKaterina Kampoli
Katerina Kampoli
ZKZoi Kakoseou
Zoi Kakoseou
Michalis V KaramouzisMichalis V Karamouzis
Michalis V Karamouzis
The efficacy of S-1 combined with a platinum agent in the first-line setting and in patients with advanced gastric adenocarcinoma has been previously demonstrated in randomized clinical trials. However, real-world data regarding S-1 efficacy in European patients remains limited. In the present study, we reviewed the data of a European cohort of patients with advanced gastric cancer treated with first-line therapy consisting of S-1 in combination with a platinum agent. Forty-eight patients (29 with locally advanced/inoperable and 19 with metastatic disease) were treated with S-1 plus oxaliplatin (33 patients) or S1 plus cisplatin (15 patients). The Cox regression analysis, adjusted with propensity score, indicated that the use of cisplatin as compared to oxaliplatin was associated with increased risk of death (HR 9.634, p = 0.000). Four SAEs (serious adverse events) GIII were recorded (1 fatigue, 1 neutropenia, 1 anemia, 1 diarrhea) in 3 patients. S-1 combination with a platinum agent in the first-line setting in European patients with advanced gastric cancer results to similar survival outcomes and toxicity with previously reported data from Asian populations. S-1 combination with oxaliplatin seems to be associated with superior efficacy as compared to cisplatin.