Colorectal cancer (CRC) remains one of the leading causes of cancer-related deaths worldwide, largely due to late-stage diagnosis and limited efficacy of current therapies. 5-Fluorouracil (5-FU) is the standard chemotherapeutic agent used in CRC treatment; however, its effectiveness is often hampered by resistance, toxicity, and suboptimal outcomes in advanced-stage tumors. Recent evidence suggests that gut microbiota-derived short-chain fatty acids (SCFAs) exert anticancer effects and may hold promise as therapeutic adjuvants. In this study, we investigated the potential of a physiologically relevant mixture of SCFAs to enhance the efficacy of 5-FU against CRC. Using a combination of 2D monolayer cultures, 3D models, and the in vivo chicken chorioallantoic membrane (CAM) assay, we demonstrated that SCFAs positively affect the antitumor effects of low-dose 5-FU. SCFAs contributed to the inhibition of CRC cell growth, proliferation, survival, and migration, with an overall increase of the anti-tumour effects observed across the different models. The combined treatment led to a significant reduction in tumour size in the CAM assay, contributing for an improvement of the effects of 5-FU alone. To our knowledge, this is the first report showing that physiologically relevant SCFA combinations can be harnessed to improve the therapeutic index of 5-FU in CRC, in a context-dependent manner. These findings support the development of microbiota-targeted co-adjuvant strategies to optimize CRC chemotherapy, reduce treatment toxicity, and improve patient outcomes, which is important given the clinical interest in microbiome-chemotherapy interactions.

BACKGROUND:Pancreatic cancer (PC) and colorectal cancer (CRC) are among the most lethal malignancies, with growing evidence pointing to the gut microbiota's role in their progression. This study aimed to explore the anticancer potential of two microbiota-derived postbiotics, N-acetylcysteine (NAC) and tetrahydro β-carboline carboxylic acid (THC), in targeting some hallmark traits of PC and CRC, both as standalone agents and in combination with standard chemotherapeutics (gemcitabine for PC and 5-fluorouracil (5-FU) for CRC). METHODS:Cell viability assays and IC50 determination was assessed using either the Muse™ Count & Viability Kit or the Sulforhodamine B assay; cell death was determined by Annexin V/Propidium Iodide and cell cycle assessed by Propidium Iodide was analyzed by flow cytometry. RESULTS:Here, we found that NAC selectively reduced the viability of PC cells BxPC-3 without triggering apoptosis, while effectively inducing apoptosis in PC cells Panc-1 and in CRC cell lines. THC exhibited stronger anticancer activity, inhibiting proliferation and promoting apoptosis in all tested PC and CRC cells, even at lower concentrations. Combination treatments yielded promising enhancement effects. NAC enhanced the cytotoxicity of gemcitabine in Panc-1 cells through increased apoptosis. NAC, when combined with 5-FU, also increased apoptosis of CRC cells. THC further potentiated gemcitabine's impact on Panc-1 cells by increasing apoptosis and by inducing cell cycle changes in BxPC-3. In the CRC model, THC co-treatment with 5-FU reduced cell viability and increased apoptosis in all cells. CONCLUSIONS:These findings provide preliminary in vitro evidence supporting the potential of integrating microbiota-derived postbiotics with conventional chemotherapy both in PC and CRC.

Kirsten rat sarcoma viral oncogene homolog (KRAS) belongs to the GTPase RAS superfamily, which regulates several cell-signaling pathways involved in the control of important cellular functions, including apoptosis. Oncogenic mutations in KRAS are considered the most common gain-of-function mutations, affecting 30-50 % of colorectal cancer (CRC) patients. While RAS proteins usually play an anti-apoptotic role, little is known about the involvement of KRAS mutations in apoptosis regulation. Here, we aimed to elucidate the role of mutated human KRAS in the regulation of BAX, a key pro-apoptotic member of the Bcl-2 family. For this purpose, we took advantage of the simpler yeast model Saccharomyces cerevisiae, using cells deficient in the main yeast RAS isoform (ras2 Delta) co-expressing wild-type KRAS (KRASWT) or the most frequent KRAS mutations found in CRC- KRASG12D, KRASG12V or KRASG13D, along with human BAX. We show that, in comparison with KRASWT, KRAS mutants confer resistance to BAX-induced death and cytochrome c (cyt c ) release. The modulation of BAX by KRAS isoforms seems to result from a direct interaction between these proteins, as they co-localize at the mitochondria and there is evidence they may physically interact. We further show that acetic acid significantly increased cell death in cells expressing BAX and co-expressing oncogenic KRAS mutants, but not KRASWT. This suggests a potential mechanism explaining the increased sensitivity of CRC cells harboring a KRAS-activated pathway to acetate. These findings contribute to a clearer understanding of how KRAS regulate BAX function, a relevant aspect in tumor progression.

Acute myeloid leukemia (AML) comprises a diverse group of blood cancers with varying genetic, phenotypic, and clinical traits, making development of targeted therapy challenging. Metabolic reprogramming in AML has been described as relevant for chemotherapy effectiveness. 3-Bromopyruvate (3-BP) is an anticancer agent that undermines energy metabolism of cancer cells. However, the effect of 3-BP in hematologic malignancies, such as AML, needs further investigation. Thus, we aimed to explore 3-BP as a chemo-sensitizing agent in AML. Different approaches of combining 3-BP with classical chemotherapy (daunorubicin and cytarabin) were tested in diverse AML cell lines. Cell sensitivity to the different drug combinations was analyzed by Trypan blue staining. The effect of pre-treatment with a non-toxic concentration of 3-BP was assessed on the AML cell metabolic profile (Western blot and immunofluorescence), mitochondrial activity (cytometry flow), and antioxidant capacity (colorimetric detection kit). KG-1 and MOLM13 cells showed increased sensitivity to chemotherapy (decreased EC50 values) after exposure to a non-toxic concentration (5 μM) of 3-BP. In both cell lines, 5 μM 3-BP decreased glucose consumption without changing extracellular lactate levels. 5 μM 3-BP treatment increased reactive oxygen species levels and decreased cell antioxidant capacity by depleting reduced glutathione levels in both KG-1 and MOLM13 cells. Our results demonstrate that non-toxic concentrations of 3-BP enhance the effect of classical chemotherapy in AML cells through a pro-oxidant mechanism. These data unveiled a new approach for AML treatment, using 3-BP or other pro-oxidant agents as co-adjuvants of chemotherapy, subsiding chemotherapy-induced side effects.

Colorectal cancer (CRC) is the third most diagnosed and the second leading cause of cancer-related deaths globally, often due to late detection and limited treatment options. Recent studies have linked alterations in gut microbiota to CRC, particularly emphasizing the role of short-chain fatty acids (SCFAs) like acetate, propionate, and butyrate in shaping the tumor microenvironment (TME). SCFAs contribute to CRC pathogenesis by inducing lysosomal membrane permeabilization, cell cycle arrest, and apoptosis in cancer cells. Extracellular vesicles (EVs) are membrane-bound vesicles that facilitate intercellular communication and have gained attention as promising non-invasive biomarkers for cancer diagnosis and treatment monitoring. EVs participate in cellular response mechanisms to external stimuli by transferring proteins, lipids, and nucleic acids between cells, thus modulating target cell behavior and promoting coordinated responses to stress and environmental challenges. This process is essential for cellular adaptation and plays a significant role in pathophysiological processes, including tumor progression and immune modulation, making EVs highly relevant in clinical research. This study examined the impact of SCFAs on EV production and phenotype in CRC cells. The results indicated a notable increase in EV-sized particles following SCFA treatment of colorectal cell lines, particularly in the SW480 CRC cell line. For CRC cell lines, while co-precipitated protein levels remained stable, there was a slight decrease in cellular DNA and an increase in EV-associated DNA. KRAS-mutant SW480 cells exhibited the most pronounced response, emphasizing their heightened sensitivity to SCFA. Notably, microsatellite instability - a key biomarker for immunotherapy in CRC - was detected in both small and large EV populations from BRAF-mutant RKO cells after SCFA treatment, even at low DNA concentrations. These findings underscore the potential of EVs for non-invasive detection of molecular markers, paving the way for further exploration of their role in precision oncology. ### Competing Interest Statement The authors have declared no competing interest.

Specific cancer therapy remains a problem to be solved. Breast and colorectal cancer are among the cancers with the highest prevalence and mortality rates. Although there are some therapeutic options, there are still few effective agents for those cancers, which constitutes a clinical problem that requires further research efforts. Lysosomes play an important role in cancer cells’ survival, and targeting lysosomes has gained increased interest. In recent years, our team has been synthetizing and testing novel benzo[a]phenoxazine derivatives, as they have been shown to possess potent pharmacological activities. Here, we investigated the anticancer activity of three of the most potent derivatives from our library, C9, A36, and A42, on colorectal- and breast-cancer-derived cell lines, and compared this with the effect on non-neoplastic cell lines. We observed that the three compounds were selective for the cancer cells, namely the RKO colorectal cancer cell line and the MCF7 breast cancer cell line. In both models, the compounds reduced cell proliferation, cell survival, and cell migration, accumulated on the lysosome, and induced cell death accompanied by lysosomal membrane permeabilization (LMP), increasing the intracellular pH and ROS accumulation. Our results demonstrated that these compounds specifically target lysosomes from cancer cells, making them promising candidates as LMP inducers for cancer therapy.

Colorectal cancer (CRC) is a leading cause of death worldwide. Conventional therapies are available with varying effectiveness. Acetate, a short-chain fatty acid produced by human intestinal bacteria, triggers mitochondria-mediated apoptosis preferentially in CRC but not in normal colonocytes, which has spurred an interest in its use for CRC prevention/therapy. We previously uncovered that acetate-induced mitochondrial-mediated apoptosis in CRC cells is significantly enhanced by the inhibition of the lysosomal protease cathepsin D (CatD), which indicates both mitochondria and the lysosome are involved in the regulation of acetate-induced apoptosis. Herein, we sought to determine whether mitochondrial function affects CatD apoptotic function. We found that enhancement of acetate-induced apoptosis by CatD inhibition depends on oligomycin A-sensitive respiration. Mechanistically, the potentiating effect is associated with an increase in cellular and mitochondrial superoxide anion accumulation and mitochondrial mass. Our results provide novel clues into the regulation of CatD function and the effect of tumor heterogeneity in the outcome of combined treatment using acetate and CatD inhibitors.

The demand for new fluorophores for different biological target imaging is increasing. Benzo[a]phenoxazine derivatives are fluorochromophores that show promising optical properties for bioimaging, namely fluorescent emission at the NIR of the visible region, where biological samples have minimal fluorescence emission. In this study, six new benzo[a]phenoxazinium chlorides possessing sulfonamide groups at 5-amino-positions were synthesized and their optical and biological properties were tested. Compared with previous probes evaluated using fluorescence microscopy, using different S. cerevisiae strains, these probes, with sulfonamide groups, stained the vacuole membrane and/or the perinuclear membrane of the endoplasmic reticulum with great specificity, with some fluorochromophores capable of even staining the plasma membrane. Thus, the addition of a sulfonamide group to the benzo[a]phenoxazinium core increases their specificity and attributes for the fluorescent labeling of cell applications and fractions, highlighting them as quite valid alternatives to commercially available dyes.

Colorectal cancer (CRC) is among the most deadly cancers worldwide. Current therapeutic strategies have low success rates and several side effects. This relevant clinical problem requires the discovery of new and more effective therapeutic alternatives. Ruthenium drugs have arisen as one of the most promising metallodrugs, due to their high selectivity to cancer cells. In this work we studied, for the first time, the anticancer properties and mechanisms of action of four lead Ru-cyclopentadienyl compounds, namely PMC79, PMC78, LCR134 and LCR220, in two CRC-derived cell lines (SW480 and RKO). Biological assays were performed on these CRC cell lines to evaluate cellular distribution, colony formation, cell cycle, proliferation, apoptosis, and motility, as well as cytoskeleton and mitochondrial alterations. Our results show that all the compounds displayed high bioactivity and selectivity, as shown by low half-maximal inhibitory concentrations (IC50) against CRC cells. We observed that all the Ru compounds have different intracellular distributions. In addition, they inhibit to a high extent the proliferation of CRC cells by decreasing clonogenic ability and inducing cell cycle arrest. PMC79, LCR134, and LCR220 also induce apoptosis, increase the levels of reactive oxygen species, lead to mitochondrial dysfunction, induce actin cytoskeleton alterations, and inhibit cellular motility. A proteomic study revealed that these compounds cause modifications in several cellular proteins associated with the phenotypic alterations observed. Overall, we demonstrate that Ru compounds, especially PMC79 and LCR220, display promising anticancer activity in CRC cells with a high potential to be used as new metallodrugs for CRC therapy.

Colorectal cancer (CRC) has been ranked as one of the cancer types with a higher incidence and one of the most mortal. There are limited therapies available for CRC, which urges the finding of intracellular targets and the discovery of new drugs for innovative therapeutic approaches. In addition to the limited number of effective anticancer agents approved for use in humans, CRC resistance and secondary effects stemming from classical chemotherapy remain a major clinical problem, reinforcing the need for the development of novel drugs. In the recent years, the phenoxazines derivatives, Nile Blue analogues, have been shown to possess anticancer activity, which has created interest in exploring the potential of these compounds as anticancer drugs. In this context, we have synthetized and evaluated the anticancer activity of different benzo[a]phenoxazine derivatives for CRC therapy. Our results revealed that one particular compound, BaP1, displayed promising anticancer activity against CRC cells. We found that BaP1 is selective for CRC cells and reduces cell proliferation, cell survival, and cell migration. We observed that the compound is associated with reactive oxygen species (ROS) generation, accumulates in the lysosomes, and leads to lysosomal membrane permeabilization, cytosolic acidification, and apoptotic cell death. In vivo results using a chicken embryo choriollantoic membrane (CAM) assay showed that BaP1 inhibits tumor growth, angiogenesis, and tumor proliferation. These observations highlight that BaP1 as a very interesting agent to disturb and counteract the important roles of lysosomes in cancer and suggests BaP1 as a promising candidate to be exploited as new anticancer lysosomal-targeted agent, which uses lysosome membrane permeabilization (LMP) as a therapeutic approach in CRC.

Finding new therapeutic approaches towards colorectal cancer (CRC) is of increased relevance, as CRC is one of the most common cancers worldwide. CRC standard therapy includes surgery, chemotherapy, and radiotherapy, which may be used alone or in combination. The reported side effects and acquired resistance associated with these strategies lead to an increasing need to search for new therapies with better efficacy and less toxicity. Several studies have demonstrated the antitumorigenic properties of microbiota-derived short-chain fatty acids (SCFAs). The tumor microenvironment is composed by non-cellular components, microbiota, and a great diversity of cells, such as immune cells. The influence of SCFAs on the different constituents of the tumor microenvironment is an important issue that should be taken into consideration, and to the best of our knowledge there is a lack of reviews on this subject. The tumor microenvironment is not only closely related to the growth and development of CRC but also affects the treatment and prognosis of the patients. Immunotherapy has emerged as a new hope, but, in CRC, it was found that only a small percentage of patients benefit from this treatment being closely dependent on the genetic background of the tumors. The aim of this review was to perform an up-to-date critical literature review on current knowledge regarding the effects of microbiota-derived SCFAs in the tumor microenvironment, particularly in the context of CRC and its impact in CRC therapeutic strategies. SCFAs, namely acetate, butyrate, and propionate, have the ability to modulate the tumor microenvironment in distinct ways. SCFAs promote immune cell differentiation, downregulate the expression of pro-inflammatory mediators, and restrict the tumor-induced angiogenesis. SCFAs also sustain the integrity of basement membranes and modulate the intestinal pH. CRC patients have lower concentrations of SCFAs than healthy individuals. Increasing the production of SCFAs through the manipulation of the gut microbiota could constitute an important therapeutic strategy towards CRC due to their antitumorigenic effect and ability of modulating tumor microenvironment.

A previously healthy 10-year-old boy presented to the emergency department with 2 days of persistent and severe epigastric abdominal pain with anorexia and mild constipation but no nausea or vomiting. No fever, pyrosis, respiratory difficulty, or urinary or genital complaints were present. The patient denied any history of abdominal trauma. On admission, he was mildly tachycardic (100 bpm), normotensive (115/58 mm Hg), and afebrile (tympanic temperature 36.4°C). Focal tenderness on the epigastrium and umbilical region was elicited on abdominal palpation; Blumberg, Rovsing, Markle, and vesicular Murphy signs were absent. No leukocytosis was present (8.1 × 109/L; normal range 4.5-13.5 × 109/L); C-reactive protein was mildly elevated (7.8 mg/L; normal range <5 mg/L). Serum cholestasis markers and liver enzymes were normal. Results of a severe acute respiratory syndrome coronavirus 2 test was negative. Given the severity of the complaints, a radiograph of the abdomen was obtained, and no signs of intestinal obstruction or perforation were noted. Ultrasonography identified a discrete fatty density at the epigastric and right lumbar regions (Figure 1). Computed tomography scan of the abdomen demonstrated an attenuated fatty lesion with surrounding inflammatory changes in the adjacent fat planes in the fissure of falciform ligament, compatible with infarction (Figure 2).Figure 2A, Axial and B, sagittal enhanced computed tomography scans show an oval hypodense mass with thick hyperdense rim and fat stranding, extended along the course of the falciform ligament (circles). C, Coronal enhanced computed tomography scan shows an enlarged and heterogeneous falciform ligament and fat stranding of adjacent planes, close to falciform ligament course (arrows).View Large Image Figure ViewerDownload Hi-res image Download (PPT) After 1 dose of ibuprofen, the pain resolved almost completely. A trial of conservative treatment with oral nonsteroid anti-inflammatory medication was attempted, and complete resolution of the symptoms occurred after 5 days. The falciform ligament is the anatomical division between the 2 hepatic lobes and extends from the superior hepatic border to the inferior diaphragmatic margin. Besides the ligamentum teres and paraumbilical veins, it also contains extraperitoneal fat.1Al-Jaberi T.M. Gharaibeh K.I. Yaghan R.J. Torsion of abdominal appendages presenting with acute abdominal pain.Ann Saudi Med. 2000; 20: 211-213Crossref PubMed Scopus (16) Google Scholar,2Maccallum C. Eaton S. Chubb D. Franzi S. Torsion of fatty appendage of falciform ligament: acute abdomen in a child.Case Rep Radiol. 2015; 2015: 293491PubMed Google Scholar The falciform ligament is rarely cause for pathologic conditions; congenital, neoplastic and infective cysts, internal hernia, and fatty-falciform ligament appendage torsion (F-FLAT) are possible disorders. F-FLAT is caused by torsion of an abnormally long lipomatous appendage, leading to ischemia and usually presenting with focal epigastric pain.3Rousslang L.K. McCoy M.F. Gould C.F. Falciform ligament appendagitis after Roux-en-Y bypass surgery mimicking acute cholecystitis.BMJ Case Rep. 2020; 13: e235642Crossref PubMed Scopus (3) Google Scholar Adding to the nonspecific symptoms, laboratory tests are usually normal or reveal mild inflammation.4Chieng J.S.L. Leow K.S. Lim T.C. Clinics in diagnostic imaging (203). Focal infarction of the falciform ligament fatty appendage.Singapore Med J. 2020; 61: 15-18Crossref PubMed Scopus (1) Google Scholar Consequently, imaging techniques play a central role in the correct diagnosis of F-FLAT.4Chieng J.S.L. Leow K.S. Lim T.C. Clinics in diagnostic imaging (203). Focal infarction of the falciform ligament fatty appendage.Singapore Med J. 2020; 61: 15-18Crossref PubMed Scopus (1) Google Scholar,5Indiran V. Dixit R. Maduraimuthu P. Unusual cause of epigastric pain: intra-abdominal focal fat infarction involving appendage of falciform ligament—case report and review of literature.GE Port J Gastroenterol. 2018; 25: 179-183Crossref PubMed Scopus (8) Google Scholar F-FLAT is usually self-limited.4Chieng J.S.L. Leow K.S. Lim T.C. Clinics in diagnostic imaging (203). Focal infarction of the falciform ligament fatty appendage.Singapore Med J. 2020; 61: 15-18Crossref PubMed Scopus (1) Google Scholar, 5Indiran V. Dixit R. Maduraimuthu P. Unusual cause of epigastric pain: intra-abdominal focal fat infarction involving appendage of falciform ligament—case report and review of literature.GE Port J Gastroenterol. 2018; 25: 179-183Crossref PubMed Scopus (8) Google Scholar, 6Horak R.D. Mega J.D. Tanton P.J. Criman E.T. Tabak B.D. Rooks V.J. Fatty-falciform ligament appendage torsion (F-FLAT): diagnosis and management in a pediatric patient.Radiol Case Rep. 2020; 15: 181-185Crossref PubMed Scopus (6) Google Scholar In most cases, conservative treatment with nonsteroidal anti-inflammatory medication is considered first-line treatment, especially today, when the diagnosis is possible without the need for surgical exploration.2Maccallum C. Eaton S. Chubb D. Franzi S. Torsion of fatty appendage of falciform ligament: acute abdomen in a child.Case Rep Radiol. 2015; 2015: 293491PubMed Google Scholar,6Horak R.D. Mega J.D. Tanton P.J. Criman E.T. Tabak B.D. Rooks V.J. Fatty-falciform ligament appendage torsion (F-FLAT): diagnosis and management in a pediatric patient.Radiol Case Rep. 2020; 15: 181-185Crossref PubMed Scopus (6) Google Scholar Despite the rarity of the entities that compose intra-abdominal focal fat infarctions, surgeons, pediatricians, and radiologists should include those in the differential diagnosis in cases of pediatric acute abdomen with normal appendix, preventing unnecessary surgical procedures.2Maccallum C. Eaton S. Chubb D. Franzi S. Torsion of fatty appendage of falciform ligament: acute abdomen in a child.Case Rep Radiol. 2015; 2015: 293491PubMed Google Scholar

KRAS hotspot mutations are difficult to target, highlighting the need of developing new specific target drugs for cancers driven by these mutations, like colorectal cancer (CRC). Here, we discover a new ruthenium compound, PMC79, that inhibits specifically mutated KRAS and the downstream signaling ERK and AKT proteins both “in vitro” and “in vivo”. We demonstrated that PMC79 inhibits KRAS mutated kinase activity and is selective for KRAS mutations not affecting the KRAS wild-type protein. KRAS inhibition is not dependent on actin polymerization or on proteasome. Molecular docking analysis suggests that this effect might result from protein dynamics associated with the mutations. We demonstrated that low doses of PMC79 potentiate 5-fluorouracil anticancer effect. “In vivo” PMC79 “proof of concept” showed that it reduces tumor growth in the CAM-xenograft model and induces necrosis of the tumor in the xenograft mice model. PMC79 is a promising new “magic bullet” for CRCs harboring mutated KRAS.

The need for new therapeutic approaches for triple-negative breast cancer is a clinically relevant problem that needs to be solved. Using a multi-targeting approach to enhance cancer cell uptake, we synthesized a new family of ruthenium(II) organometallic complexes envisaging simultaneous active and passive targeting, using biotin and polylactide (PLA), respectively. All compounds with the general formula, [Ru(η5-CpR)(P)(2,2′-bipy-4,4′-PLA-biotin)][CF3SO3], where R is -H or -CH3 and P is P(C6H5)3, P(C6H4F)3 or P(C6H4OCH3)3, were tested against triple-negative breast cancer cells MDA-MB-231 showing IC50 values between 2.3–14.6 µM, much better than cisplatin, a classical chemotherapeutic drug, in the same experimental conditions. We selected compound 1 (where R is H and P is P(C6H5)3), for further studies as it was the one showing the best biological effect. In a competitive assay with biotin, we showed that cell uptake via SMVT receptors seems to be the main transport route into the cells for this compound, validating the strategy of including biotin in the design of the compound. The effects of the compound on the hallmarks of cancer show that the compound leads to apoptosis, interferes with proliferation by affecting the formation of cell colonies in a dose-dependent manner and disrupts the cell cytoskeleton. Preliminary in vivo assays in N: NIH(S)II-nu/nu mice show that the concentrations of compound 1 used in this experiment (maximum 4 mg/kg) are safe to use in vivo, although some signs of liver toxicity are already found. In addition, the new compound shows a tendency to control tumor growth, although not significantly. In sum, we showed that compound 1 shows promising anti-cancer effects, bringing a new avenue for triple-negative breast cancer therapy.

The colon microbiota is an important player in colorectal cancer (CRC) development, which is responsible for most of the cancer-related deaths worldwide. During carcinogenesis, the colon microbiota composition changes from a normobiosis profile to dysbiosis, interfering with the production of short-chain fatty acids (SCFAs). Each SCFA is known to play a role in several biological processes but, despite their reported individual effects, colon cells are exposed to these compounds simultaneously and the combined effect of SCFAs in colon cells is still unknown. Our aim was to explore the effects of SCFAs, alone or in combination, unveiling their biological impact on CRC cell phenotypes. We used a mathematical model for the prediction of the expected SCFA mixture effects and found that, when in mixture, SCFAs exhibit a concentration addition behavior. All SCFAs, alone or combined at the physiological proportions founded in the human colon, revealed to have a selective and anticancer effect by inhibiting colony formation and cell proliferation, increasing apoptosis, disturbing the energetic metabolism, inducing lysosomal membrane permeabilization, and decreasing cytosolic pH. We showed for the first time that SCFAs are specific towards colon cancer cells, showing promising therapeutic effects. These findings open a new road for the development of alternatives for CRC therapy based on the increase in SCFA levels through the modulation of the colon microbiota composition.

KRAS, one of the RAS protein family members, plays an important role in autophagy and apoptosis, through the regulation of several downstream effectors. In cancer cells, KRAS mutations confer the constitutive activation of this oncogene, stimulating cell proliferation, inducing autophagy, suppressing apoptosis, altering cell metabolism, changing cell motility and invasion and modulating the tumor microenvironment. In order to inhibit apoptosis, these oncogenic mutations were reported to upregulate anti-apoptotic proteins, including Bcl-xL and survivin, and to downregulate proteins related to apoptosis induction, including thymine-DNA glycosylase (TDG) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). In addition, KRAS mutations are known to induce autophagy in order to promote cell survival and tumor progression through MAPK and PI3K regulation. Thus, these mutations confer resistance to anti-cancer drug treatment and, consequently, result in poor prognosis. Several therapies have been developed in order to overcome KRAS-induced cell death resistance and the downstream signaling pathways blockade, especially by combining MAPK and PI3K inhibitors, which demonstrated promising results. Understanding the involvement of KRAS mutations in apoptosis and autophagy regulation, might bring new avenues to the discovery of therapeutic approaches for CRCs harboring KRAS mutations.

Colorectal cancer (CRC) is one of the most common malignancies and one of the leading causes of cancer-related death worldwide, urging the need for new and more efficient therapeutic approaches. Ruthenium complexes have emerged as attractive alternatives to traditional platinum-based compounds in the treatment of CRC. This work aims to evaluate anti-CRC properties, as well as to identify the mechanisms of action of ruthenium complexes with the general formula [Ru(η5-C5H4R)(PPh3)(4,4′-R′-2,2′-bipyridine)][CF3SO3], where R = CH3, CHO or CH2OH and R′ = H, CH3, CH2OH, or dibiotin ester. The complexes (Ru 1–7) displayed high bioactivity, as shown by low IC50 concentrations against CRC cells, namely, RKO and SW480. Four of the most promising ruthenium complexes (Ru 2, 5–7) were phenotypically characterized and were shown to inhibit cell viability by decreasing cell proliferation, inducing cell cycle arrest, and increasing apoptosis. These findings were in accordance with the inhibition of MEK/ERK and PI3K/AKT signaling pathways. Ruthenium complexes also led to a decrease in cellular clonogenic ability and cell migration, which was associated with the disruption of F-actin cytoskeleton integrity. Here, we demonstrated that ruthenium complexes, especially Ru7, have a high anticancer effect against CRC cells and are promising drugs to be used as a new therapeutical strategy for CRC treatment.

An unbalanced diet is one of the well-known risk factors for the development of colorectal cancer (CRC). This type of cancer is currently the main cause of cancer-related deaths worldwide, urging the need for new and more effective preventive and therapeutic approaches. It is already known that CRC patients have alterations in the microbial community and metabolism. In this regard, a concept that has been recently attracting the attention of the scientific community is the development of functional food or nutraceuticals, as a new and more effective strategy to overcome CRC patient-associated dysbiosis. Particularly, dairy product enriched diets are the major dairy source of dietary calcium, vitamin D and folate intake, which are well-known to have a protective effect against CRC development. In addition, these products are rich in both pre- and probiotics, constituting a double strategy to modulate both the intestinal microbiota composition and the production of microbial metabolites. Short-chain fatty acids (SCFA), namely, acetate, butyrate, and propionate, are major contributors to colonic homeostasis since they regulate several biological and metabolic processes. In this review, we performed a state of art study concerning the use of dietary patterns, specifically the dairy-derived diet, in the modulation of the human microbiota and their potential use as pre-, pro- or synbiotics for the development of new preventive and therapeutic strategies for CRC.

KRAS mutations are one of the most frequent oncogenic mutations of all human cancers, being more prevalent in pancreatic, colorectal, and lung cancers. Intensive efforts have been encouraged in order to understand the effect of KRAS mutations, not only on tumor cells but also on the dynamic network composed by the tumor microenvironment (TME). The relevance of the TME in cancer biology has been increasing due to its impact on the modulation of cancer cell activities, which can dictate the success of tumor progression. Here, we aimed to clarify the pro- and anti-inflammatory role of KRAS mutations over the TME, detailing the context and the signaling pathways involved. In this review, we expect to open new avenues for investigating the potential of KRAS mutations on inflammatory TME modulation, opening a different vision of therapeutic combined approaches to overcome KRAS-associated therapy inefficacy and resistance in cancer.

The small molecule 3-bromopyruvate (3BP), is an anticancer molecule that acts by hindering glycolysis and mitochondrial function leading to energy depletion and consequently, to cell death. In this work we have focused on understanding how the glycolytic inhibition affects cancer cell structural features. We showed that 3BP leads to a drastic decrease in the levels of β-actin and α-tubulin followed by disorganization and shrinkage of the cytoskeleton in breast cancer cells. 3BP inhibits cell migration and colony formation independently of the activity of metalloproteinases. To disclose if these structural alterations occurred prior to 3BP toxic effect, non-toxic concentrations of 3BP were used and we could observe that 3BP was able to inhibit energy production and induce loss of β-actin and α-tubulin proteins. This was accompanied with alterations in cytoskeleton organization and an increase in E-cadherin levels which may indicate a decrease in cancer cells aggressiveness. In this study we demonstrate that 3BP glycolytic inhibition of breast cancer cells is accompanied by cytoskeleton disruption and consequently loss of migration ability, suggesting that 3BP can potentially be explored for metastatic breast cancer therapy.