Table 2 Anticancer activity of some medicinal plant species reported in Kenya for cancer treatment

Toddalia asiatica

8-Methoxynorchelerythrine (1), 11-demethylrhoifoline B (2), 8-methoxynitidine (3), 8-acetylnorchelerythrine (4), 8,9,10,12-tetramethoxynorchelerythrine (5), isointegriamide (6); 1-demethyl dicentrinone (7), 11-hydroxy-10-methoxy-(2,3)-methylenedioxytetrahydroprotoberberine (8), rhoifoline B (9), pancorine (10), 8-methoxychelerythrine (11), arnottianamide (12), oxynitidine (13), oxysanguinarine (14), dicentrinone (15), (2,3,10,11)-dimethylenedioxytetrahydroprotoberberine (16), skimmianine (17), 5-methoxydictamnine (18) (Hu et al. 2014), benzo[c]phenanthridine derivatives: dihydronitidine (19), nitidine (20) and demethylnitidine (21) (Iwasaki et al. 2009), 6-(3-methyl-2-butenyl)-5,7-Dimethoxycoumarin (toddaculin) (22), 6-(2,3-Epoxy-3-methylbutyl)-5,7-dimethoxycoumarin (aculeatin) (23), 6-(3-Methyl-2-butenyloxy)-5,7-dimethoxycoumarin (24), 8-(3-Methyl-2-butenyl)-6,7-dimethoxycoumarin (O-methylcedrelopsin) (25), 6-(2-Hydroxy-3-methyl-3-butenyl)-5,7-dimethoxycoumarin (toddanol) (26), 6-(2,3-Dihydroxy-3-methylbutyl)-5,7-dimethoxycoumarin (toddalactone) (27), 5,7-Dimethoxy-4-methylcoumarin (28) (Vázquez et al. 2012), 8S-10-Odemethylbocconoline (29), oxynorchelerythrine (30), phellopterin (31), O-methylcedrelopsin (32), toddanone (33) (Sukieum et al. 2017)

Cytotoxicity recorded against human A549 (lung cancer), BGC-823 cells (gastric carcinoma), HCT15 (colon cancer), HeLa cells (cervical cancer), HepG2 (hepatocellular carcinoma), MCF-7 (breast cancer), SK-MEL-2 (skin cancer), and SGC-7901 (gastric adenocarcinoma) cell lines (Hu et al. 2014). Benzo[c]phenanthridine alkaloids (1–5) and secobenzo [c]phenantridine alkaloids showed cytotoxicity against the cancer cell lines; 4 was the most potent with IC₅₀ values ranging from 1.3 to 2.5 lg/mL. The aporphine-type alkaloids had moderate cytotoxicity on the tested cell lines, while berberine-type and indole-type alkaloids had modest activities (Hu et al. 2014)

Derivatives 20 and 21 selectively reduced proliferation of murine (LLC) and human lung adenocarcinoma (A549) cells in vitro, while 19 inhibited proliferation of in a subcutaneous A549 xenograft model (Iwasaki et al. 2009). Coumarins (22–27) had potential cytotoxicity and antiproliferative activity against U-937 cells with IC₅₀ = 51.38 ± 4.39 (22), 92.44 ± 2.82 (23), 190.5 ± 3.18 (24), 99.74 ± 2.34 (25), > 100 (26), 165.0 ± 4.06 (27), > 1000 µM (28) and CC₅₀ = 138.90 ± 3.50, 459.10 ± 3.42, 548.60 ± 5.20, 154.90 ± 3.34, > 100, 320.40 ± 3.38, > 1000 µM, respectively. Toddaculin (22) induced cell differentiation effects and apoptosis (Vázquez et al. 2012)

Alkaloids (29, 30) from root extract fractions had cytotoxic effects against human epidermoid carcinoma of oral cavity (KB) cells with IC₅₀ = 21.69 and 43.77 μg/mL, respectively. For human small cell lung cancer (NCI-H187) cells, 30–33 had weak cytotoxicity with IC₅₀ from 21 to 35 μg/mL (Sukieum et al. 2017)

Abelmoschus esculentus

Isoquercitrin (34), quercetin (35), hyperoside (hyperin), coumarin scopoletin and uridine (Chaemsawang et al. 2019)

Cytotoxicity of extracts reported against breast cancer (MCF-7), hepatocellular carcinoma (HepG2) and cervical carcinoma (HeLa) cell lines (Chaemsawang et al. 2019). Isoquercitrin inhibited urinary bladder, pancreatic and colon cancer progress (Amado et al. 2014; Chen et al. 2015, 2016)

Extracts induced significant cell growth inhibition (63%) in human breast cancer (MCF-7) and skin fibroblast (CCD-1059 sk) cells. The expression of pro-apoptotic caspase-3, caspase-9, and p21 genes was increased in MCF-7 cells (Monte et al. 2014)

Albizia coriaria

Triterpenoid saponins: coriarioside A (36) and coriarioside B, gummiferaoside C (37), acacic acid glycosides, lupeol (38), lupenone, betulinic acid, acacic acid lactone, (+)–catechin and benzyl alcohol (Byamukama et al. 2015; Noté et al. 2009, 2010; Omara et al. 2022)

Coriarioside A and gummiferaoside C from root bark showed cytotoxicity against two colorectal human cancer cells: HCT-116 (with IC₅₀ of 4.2 μM for Coriarioside A and 2.7 μM for gummiferaoside C) and HT-29 (with IC₅₀ 6.7 μM for Coriarioside A and 7.9 μM for gummiferaoside C) cell lines (Note et al. 2009)

Annona muricata L

Annonaceous acetogenins (muricin J, muricin K, muricin L) (Sun et al. 2014), annonacin (39), annomuricin A, annomuricin E (40), annomuricin C, annomutacin, gigantetronin (Wu et al. 1995; Yuan et al. 2003), quercetin, luteolin 3′7-di-o-glucoside, gallic acid, apigenin-6-c-glucoside, taxifolin (+) (George et al. 2012)

Aqueous leaf extracts exhibited anticancer activity with IC₅₀ values of 220, 350 and 250 μg/mL for breast cancer cell lines: MCF-7, MDA-MB231 and 4T1, respectively (Najmuddin et al. 2016). Leaf extracts recorded cytotoxicity against human bladder cancer (K562) and leukemia cancer (ECV304) cell lines (Oviedo et al. 2009)

Annonaceous acetogenins exhibited antiproliferative activity against human prostate cancer PC-3 cells (Sun et al. 2014). Fruit extracts cytotoxic against U937 histiocytic lymphoma cell line with IC₅₀ of 10.5, 18.2 and 60.9 μg/ml for ethyl acetate, hexane and methanol extracts, respectively (Valencia et al. 2011)

Annonacin caused complete suppression of 7, 12-dimethylbenz[a]anthracene (DMBA) induced and 12–0-tetradecaboylphorbol-13-acetate (TPA) promoted skin tumorigenesis in mice (Roduan et al. 2017). At 0.1 μM, annonacin induced growth arrest and apoptosis in breast cancer (MCF-7) cells (Ko et al. 2011)

Annomuricin E was cytotoxic to HT-29 colon carcinoma and CCD841 normal colon cell lines with IC₅₀ values of 5.72, 3.49 and 1.62 μg/mL for HT-29 cells at time intervals of 12, 24, and 48 h of administration, respectively (Moghadamtousi et al. 2015)

Stem extracts suppressed the expression of molecules associated to hypoxia and glycolysis in CD18/HPAF (pancreatic) cancer cells (IC₅₀ of 73.0 μg/mL) (Torres et al. 2012)

Cytotoxicity recorded against Raji cells with IC₅₀ values of 90.6, 407.2 and 260.2 μg/mL. Cytotoxic effect of chloroform and n-hexane extracts on Hela cell line gave IC₅₀ values of 127.3 and 169.2 μg/mL, respectively (Artanti et al. 2016)

Leaf extracts inhibited cell proliferation in pancreatic cancer cells (Capan-1) (Rosdi et al. 2015)

Ethanol extract of seeds showed cytotoxic effect on MDBK and HEp-2 cells (IC₅₀ values:34.5 and 55 mg/mL, respectively) at 24 h, and an IC₅₀ value of 49.6 × 10⁻³ mg/mL toward HEp-2 cells at 72 h (Betancur-Galvis et al. 1999)

Cytotoxic against kidney epithelial (VERO), stomach cancer (C-678) and human large lung cell carcinoma (H-460) cell lines with IC₅₀ values lower than 0.00022 mg/mL for all the cell lines (Quispe et al. 2006). Cytotoxicity reported against histiocytic lymphoma cell line (U937), pancreatic cancer cells (FG/COLO357), breast cancer cells (MDA-MB-435S), immortalized human keratinocytes (HaCat), normal human liver cells (WRL-68) and human skin malignant melanoma (A375) (George et al. 2012; Ménan et al. 2006; Nawwar et al. 2012; Osorio et al. 2007; Torres et al. 2012). In histiocytic lymphoma cell line, the extract had IC₅₀ value of 7.8 μg/mL. Toxicity toward FG/COLO357 with an IC₅₀ value of 200 μg/mL (Torres et al. 2012). Cytotoxic effect of n-butanolic extract of leaves against MDA-MB-435S (human breast carcinoma), HaCaT (human immortalized keratinocyte) and WRL-68 (normal human hepatic) cell lines with IC₅₀ values of 29.2, 30.1 and 52.4 μg/mL, respectively (George et al. 2012)

Ethanol extracts of leaves cytotoxic to Ehrlich Ascites Carcinoma (EACC) and breast cancer (MDA and SKBR3) cell lines with IC₅₀ values of 335.85, 248.77, and 202.33 μg/mL (Gavamukulya et al. 2014). Fruit extracts had substantial repression of breast cancer cells (MDAMB-468) growth as well as selective suppression of epidermal growth factor receptor (EGFR) with IC₅₀ of 4.8 μg/mL (Dai et al. 2011)

Acokanthera oppositifolia

Not reported

DCM and DCM: MeOH root and stem extracts had moderate in vitro anticancer activity against breast (MCF-7) and Melanoma (UACC62) cells with total growth inhibition (TGI) at 6.25–15.0 μg/mL but no activity against Renal (TK10) cells (Fouche et al. 2008)

Beta vulgaris L

Not reported

Ethanolic extract exhibited significant anticancer activity against lung cancer (A549) cell line but only a slight effect against colorectal adenocarcinoma (Caco-2) cell line at 800 μg/ml (El-Beltagi et al. 2018). Cytotoxicity against PC-3 cells led to decrease in the growth rate of the cells (3.7% in 3 days) at 29 μg/mL. Comparative cytotoxicity tests in normal human skin (FC) and liver (HC) cell lines showed that the extract were cytotoxic on the cells, though activity were lower than that of doxorubicin (8.6% compared to 100%, respectively, at 29 μg/ml concentration in a 3-day test period) (Kapadia et al. 2011)

Capsicum frutescens L

Capsaicin (41) and quercetin (Shaimaa et al. 2016)

Aqueous fruit extracts exhibited anticancer activity, (though lower than capsaicin standard) when tested against prostate (PC-3) and breast (MCF-7) cancer cell lines in vitro (Shaimaa et al. 2016)

Carica papaya L

Lycopene (42), ferulic acid, benzyl isothiocyanate, kaempferol, quercetin, chlorogenic acid, caffeic acid, beta carotene and p-coumaric acid (Melariri et al. 2011; Teng et al. 2019)

Pure lycopene and papaya juice inhibited viability of liver cancer (HepG2) cell line with IC₅₀ of 22.8 µg/mL and 20 mg/mL (Rahmat et al. 2002). Aqueous leaf extracts inhibited by apoptosis the proliferation of human breast cancer (MCF-7) cells with IC₅₀ = 1319.25 µg/mL (Nisa et al. 2017)

n-hexane seed extract dose dependently inhibited superoxide generation (IC₅₀ = 10 µg/mL) and the viability of acute promyelocytic leukemia (HL-60) cells (IC₅₀ = 20 µg/mL), comparable to that of pure benzyl isothiocyanate (Nakamura et al. 2007)

Aqueous extract of flesh (0.01– 4% v/v) inhibited the proliferation of breast cancer cell line (MCF-7) (Garcia-Solis et al. 2009). Ethanolic extract of pericarp (50–640 µg/mL) inhibited the growth of Breast cancer cell line (MCF-7) treated with sodium nitroprusside, a nitric oxide donor (Jayakumar and Kanthimathi 2011). Breast cancer cell line (T47D) was inhibited by leaf protein fraction with IC₅₀ = 2.8 mg/mL); induced apoptosis by regulation of protein expression (Hirose et al. 1998)

Aqueous extracts of leaves (1.25–27 mg/mL) exhibited a concentration-dependent anticancer effect on stomach cancer cell line (AGS), pancreatic cancer cell line (Capan-1), colon cancer cell line (DLD-1), ovarian cancer cell line (Dov-13), lymphoma cell line (Karpas), breast cancer cell line (MCF-7), neuroblastoma cell line (T98G), uterine cancer cell line (Hela), T cell leukemia cell line (CD26 negative or negative Jurkat) cell lines and suppressed DNA synthesis by suppressing the incorporation of 3H-thymidine (Morimoto et al. 2008)

Aqueous extract of leaves (0.625–20 mg/mL) inhibited the proliferative responses of both haematopoietic and solid tumor cell lines (T cell lines, H9, Jurkat, Molt-4, CCRF-CEM and HPB-ALL), Burkitt’s lymphoma cell lines (Ramos and Raji), chronic myelogenous leukemia cell line (K562), cervical carcinoma cell line (Hela), hepatocellular carcinoma cell lines (HepG2 and Huh-7), lung adenocarcinoma cell line (PC-14), pancreatic epithelioid carcinoma cell line (Panc-1), mesothelioma cell lines (H2452, H226, and MESO-4), plasma cell leukemia cell line (ARH77), anaplastic large cell lymphoma cell line (Karpas-299), breast adenocarcinoma cell line (MCF-7), mesothelioma cell line (JMN) and pancreatic adenocarcinoma cell line (Capan-1). In peripheral blood mononuclear cells, the extract reduced the production of IL-2 and IL-4, whereas increased the production of Th1 types cytokines such as IL-12p40, IL-12p70, INF-\(\gamma\) and TNF-\(\propto\). The expression of 23 immunomodulatory genes was enhanced by the addition of papaya extract (Otsuki et al. 2010)

Leaf juice not only exhibited a stronger cytotoxic effect on human squamous cell carcinoma (SCC25 cancer) cells, but also produced a significant cancer-selective effect as shown by tests on non-cancerous human keratinocyte HaCaT cells (Nguyen et al. 2016)

Catharanthus roseus (L.) G. Don

Terpenoid alkaloids: vinblastine (43) and vincristine (44), serpentine, catharanthine, ajmalicine, akuammine, lochnerine, lochnericine, tetrahydroalstonine, 3′,4′-anhydrovinblastine, serpentine, vincaleukoblastine, leurocristine, vincaleurocristine, vincarodine, vincoline, leurocolombine, viramidine, vincathicine, vincubine, isositsirikine, vincolidine, catharanthine, vindoline (45), tetrahydroalstonine, vindolinine, reserpine, coronaridine, 11-methoxy tabersonine, tetrahydroalstonine, vindorosidine, hydroxytyrosol, ferulic acid, chlorogenic acid, kaempferol, trisaccharides, quercetin and petunidin 3-O-(6-O-p-coumaroyl) (Mustafa and Verpoor 2007; Hisiger and Jolicoeur 2007)

Vindoline from leaf extracts was cytotoxic to HCT-116 colorectal carcinoma cell line at 200 μg/mL

Erythrina abbysinica

Erythrina alkaloids: erythraline, erysodine, erysotrine, 8-oxoerythraline and 11-methoxyerysodine, Abyssinones A-D (46–48) and abyssaponins: A and B (49, 50)

Cytotoxicity with LC₅₀ value > 240 μg/ml (Kapingu et al. 2006). In vitro cytotoxicity of the crude alkaloidal fraction reported against HeLa, HepG2, HEP-2, HCT-116, MCF-7 and HFB4 cell lines with IC₅₀ values of 13.8, 10.1, 8.16, 13.9, 11.4 and 12.2 µg/mL

Abyssinones A-D and abyssaponins (A and B) isolated from E. abyssinica stem bark exhibited considerable cytotoxicity against MCF-7 and MDA-MB-231 breast adenocarcinoma cell lines with IC₅₀ ranging between 12.9 and 74 µM as compared to resveratrol (IC₅₀ = 13.9–19.3 µM) (Pérez et al. 2015)

Hydnora abyssinica

None reported

Aqueous and methanolic rhizome extracts had IC₅₀ = 499.3 ± 1.3 and 27.20 ± 1.1 μg/mL against HCC 1395 cells with selectivity indices of 0.37 and 3.10, respectively, (Onyancha et al. 2018)

Kigelia africana Lam. Benth

Lapachol, 3-(2'- hydroxyethyl)-5-(2''-hydroxypropyl) dihydrofuran-2-(3H) one, specioside, verminoside and minecoside, kigelin, β-sitosterol, 1,3-dimethylkigelin and ferulic acid

DCM and DCM: MeOH root and leaf extracts had moderate in vitro anticancer activity against breast (MCF-7), renal (TK10) cells and melanoma (UACC62) cells with TGI at 8.02–42.88 μg/mL (Fouche et al. 2008). MeOH and DCM: MeOH extracts had cytotoxicity against human breast cancer (HCC 1937) cells with IC₅₀ values of 26.02 μg/ml and 55.01 μg/ml, respectively, (Mukavi et al. 2020). Seed oil suppressed human colon adenocarcinoma (Caco-2) and human embryonic kidney (HEK-293) cell growth in a dose-dependent manner (Chivandi et al. 2012). Fruit extracts increased the sub-G1 phase (apoptosis) population in HCT116 human colon cancer cells (Guon and Chung 2016)

Markhamia lutea (Benth) K. Schum

Cycloartane triterpenoids, musambins A–C and their 3-Oxyloside derivatives musambiosides A–C (Lacroix et al. 2011), oleanolic acid, pomolic acid, 2-epi-tormentic acid, musambin A, b-sitosterol-3-O-b-D-glucopyranoside (Lacroix et al. 2009; Rajendran et al. 2014)

Anticancer activity against Ehrlich Ascites Carcinoma cells with an IC₅₀ value of 27.0 μg/mL (Rajendran et al. 2014). Cytotoxicity against KB (mouth epidermoid carcinoma) and the human diploid embryonic lung cells (MRC5) though most IC₅₀ values were > 50 μg/mL (Lacroix et al. 2009)

Moringa oleifera Lam

Quercetin, kaempferol, \(\beta\)-D-glucopyranoside tetradecanoate, \(\beta\)-sitosterol, \(\beta\)-sitosterol glucoside (Kaur & Shantanu 2015), isothiocyanate, hexadecanoic acid and eugenol (Al-Asmari et al. 2015)

Cytotoxic against colon cancer (Colo-320 DM), Breast cancer (MCF-7), Ovary cancer (PA-1) and oral cancer (KB-403) cell lines with IC₉₀ value of 3.98, 17.60,12.86 and 8.40 µg/mL, respectively (Kaur and Shantanu 2015). Methanol extracts were cytotoxic to human B-lymphocyte plasmacytoma (U266B1) cell line with IC₅₀ of 0.32 µg/ml (Parvathy and Umamaheshwari 2007). Aqueous leaf extract caused a dose-dependent decrease in HeLa cell viability with IC₅₀ of 70 µg/ml (Nair and Varalakshmi 2011). Leaf extracts displayed significant anti-proliferative activity (p < 0.05) against Human liver (hepatocellular carcinoma, HepG2) and muscular (rhabdomyosarcoma, RD) cell lines (Milugo et al. 2016). The IC₅₀ of leaf extracts cytotoxicity on cisplatin-resistant ovarian cancer (A2780CP20) and prostate cancer (PC3) cell lines in a study were 0.27 and 0.17 mg/ml, respectively (Zayas-Viera et al. 2016)

Apoptosis assay performed using leaf and bark extracts on breast and colorectal cancer lines showed a remarkable increase in the number of apoptotic cells with a seven-fold increase in breast (MD-MB-231) cell line to an increase of several folds in colorectal cancer (HCT-8) cell line (Al-Asmari et al. 2016)

Leaf extracts inhibited the growth of hepatocarcinoma (HepG2), colorectal adenocarcinoma (Caco-2) and breast adenocarcinoma (MCF-7) cell lines with dichloromethane leaf extract having IC₅₀ between 112 and 133 µg/ml (Suphachai 2014). Leaf extracts caused death of 72–82% of acute myeloid leukemia cells and 77–86% of acute lymphoblastic leukemia cells after 24 h of incubation with 20 µg/ml of the extract. In the same time, 69–81% of HepG2 cells died after treatment with ethanol extract (Khalafalla et al. 2010). Leaf extracts also showed in vitro anticancer activity on human hepatocellular carcinoma (HepG2) cells. At a maximum dose of 200 mg/kg, the survival of HepG2 and non-small cell lung cancer (A549) cells were reported to decrease by 60% and 50%, respectively (Jung et al. 2015)

Leaf extract had anticancer activity against human epidermoid cancer (Hep-2) cell line with IC₅₀ of 12.5 µg/ml in the most active fraction (Krishnamurthy et al. 2015). Cytoxicity of water-soluble leaf extract reported against human alveolar epithelial cells derived from the lung cancer (A549) cell line with IC₅₀ of 166.7 µg/ml (Tiloke et al. 2013). Cell viability of leaf extract-treated A549, HepG2, CaCo2, Hek293 and Jurkat cells were reported to be reduced with IC₅₀ from 0.05 to 0.4% (Madi et al. 2016). Human pancreatic cancer cells (Panc-1, p34 and COLO-357) were inhibited by leaf extracts with IC₅₀ of 1.1, 1.5 and 1.8 mg/ml (Berkovich et al. 2013)

Seed extracts had cytotoxic potential against A549, Hep-2, HT-29 and IMR-32 cancer cell lines (Rajesh et al. 2012). β-sitosterol-3-O-glucopyranoside, 4-(α-L-rhamnosyloxy) benzyl isothiocyanate and niazimicin prevented the induction of Epstein Barr-Virus genome in Raji cells. Niazimicin delayed the formation of tumors and reduced the number of tumors in vivo (Guevara et al. 1999)

Prunus africana (Hook.f.) Kalkman

Ursolic acid, oleanolic acid, β-amyrin, atraric acid, N-butylbenzene-sulfonamide, β-sitosterol, β-sitosterol-3-O-glucoside, ferulic acid and lauric acid (Jena et al. 2016; Ngule et al. 2014; Nyamai et al. 2015)

Anti-prostate cancer activity targets fast dividing cells by impairing mitosis or by causing target cells to undergo apoptosis (Nyamai et al. 2015; Ochwang’i et al. 2014). Growth inhibition of a human prostate cancer cell line (PC-3) and epithelial cells derived from a lymph-node carcinoma of the prostate (LNCaP) by 50% at 2.5 μL/mL and also induced significant apoptosis in both cell lines (PC-3 and LNCaP) at 2.5 μL/mL compared to untreated cells. Ethanolic extract had an antimitogenic effect on prostate cancer cells by inhibiting the mitogenic action of epidermal growth factor which resulted in a decreased number of cells entering the S-phase of the cell cycle (Margalef et al. 2003). Aqueous and methanolic bark extracts had IC₅₀ = 81.9 ± 8.04 and 10.6 ± 0.7 μg/mL against human breast cancer (HCC 1395) cells with selectivity indices of 2.39 and 1.93, respectively (Onyancha et al. 2018)

Ovariodendron anisatum

Not reported

Aqueous and methanolic root extracts had IC₅₀ = 248.0 ± 5.8 and 50.6 ± 2.9 μg/mL against HCC 1395 cells with selectivity indices of 0.6 and 0.06, respectively (Onyancha et al. 2018)

Ocimum gratissimum

Phenolic compounds including procyanidin, carboxystrictosinedine, isoferullic acid, hydroxyplorentin, isoquercetin, diadzin, hyperin (Nassazi et al. 2020)

Antiproliferative activity of crude leaf extracts and methanolic fractions against human prostate (DU145), colon (CT26) and cervical (HeLa 229) cancer cells with IC₅₀ between 104.84 ± 0.44 and 2874.81 ± 0.33 μg/mL for crude (methanolic, ethyl acetate, DCM and hexane) extracts and 16.16 ± 0.14 to 1019.26 ± 0.28 μg/mL for methanolic fractions (Nassazi et al. 2020). Partially purified fractions (1.61 mg/mL) were effective in inhibiting the proliferation of prostate adenocarcinoma (PC-3) in a in a concentration-dependent manner (Ekunwe et al. 2013, 2010). Unfractionated aqueous leaf extracts presented cytostatic effects with an 80% decrease in human breast cancer cell line (MCF-7) growth at 1 mg/mL (Torres et al. 2018)

Crude extracts, its hydrophobic and hydrophilic fractions differentially inhibited breast cancer cell chemotaxis and chemoinvasion in vitro and retarded tumor growth and temporal progression of MCF10ADCIS.com xenografts (Nangia-Makker et al. 2013). Aqueous extract decreased the viability of human pulmonary adenocarcinoma (A549) cells (Chen et al. 2011). Further, leaf extracts decreased the cell viability of hepatocellular carcinoma (HCC SK-Hep1 and HA22T) cells in a dose-dependent manner (from 400 to 800 μg/mL) while there was little effect on Chang liver cells (Huang et al. 2020)

Launaea cornuta

Not reported

Aqueous and methanolic leaf extracts had IC₅₀ = 365.0 ± 15.3 and 231.7 ± 2.0 μg/mL HCC 1395 cells with selectivity indices of > 2.7 and 1.7, respectively (Onyancha et al. 2018)

Indigofera swaziensis

Not reported

Cytotoxicity reported (Hostettmann et al. 2000)

Spermacoce princeae

Not reported

Aqueous and methanolic aerial part extracts had IC₅₀ = 365.0 ± 15.3 and 231.7 ± 2.0 μg/mL against HCC 1395 cells with selectivity indices of > 2.7 and 1.7, respectively (Onyancha et al. 2018)

Fagaropsis angolensis

Not reported

Aqueous and methanolic bark extracts had IC₅₀ = 553.6 ± 15.4 and 59.4 ± 5.6 μg/mL against HCC 1395 cells with selectivity indices of 0.5 and 0.36, respectively (Onyancha et al. 2018)

Combretum tanaense

Not reported

Aqueous and methanolic root extracts had IC₅₀ =  > 1000 μg/mL (inactive) and 193.0 ± 13.2 μg/mL against HCC 1395 cells with selectivity indices of > 1 and 0.19, respectively (Onyancha et al. 2018)

Oxygonum sinuatum

Not reported

MeOH: DCM (1:1) extracts of leaves, stem and fruits had antiproliferative activity against mouse breast cancer (4T1l), human breast cancer (Hcc 1395), human prostate (22Rv1) and metastatic prostate (DU 145) cancer cell lines with IC₅₀ ranging between 181.48–867.06 μg/mL, 114.87–956.97 μg/mL and 35.84 to > 1000 μg/mL, respectively (Njuguna et al. 2018)

Maytenus senegalensis

Not reported

Methanolic root fraction was cytotoxic to Caco-2 and HepG2 cells with IC₅₀ of < 40 μg/mL. The cell deaths were mediated by apoptosis (Bah et al. 2020)

Maytenus obscura

Not reported

Aqueous extract of its stem bark elicited moderate antitumor activity against DU145, 22RV1 and HeLa cancer cell lines with IC₅₀ values of 25.03, 30.88 and 23.11 µg/mL (Kimani 2022)

Zanthoxylum chalybeum Engl

Skimmianine, furoquinoline alkaloid skimmianine, the benzophenanthidine alkaloids chelerythrine and nitidine, the aporphine alkaloids tembetarine, magnoflorine, N-methylcorydine, N-methylisocorydine (menisperine) and berberine and the phenylethyamine candicine, alkamide, fagaramide, dihydrochelerythrine, lupeol and sesamin (Omosa et al. 2019)

Extracts showed moderate cytotoxicity with IC₅₀ values below 50 µM against the drug sensitive CCRF-CEM and multidrug-resistant CEM/ADR5000 leukemia cell lines (Omosa et al. 2019). Cytotoxicity reported against human cancer cell line HL-60 cells with IC₅₀ of 137.31 μg/ml and selectivity index of 3.81 (Nibret et al. 2010). Cytotoxicity against Human gingival fibroblasts cells with IC₅₀ of 26 ± 3 μg/ml (Ocheng et al. 2016)

Zanthoxylum paracanthum

Myristic acid (50), stigmasterol (51), sesamin, 8-acetonyldihydrochelerythrine, arnottianamide, 10-methoxycanthin-6-one, canthin-6-one (52), 8-oxochelerythrine

Root bark extract showed cytotoxicity at 8.12 μg/mL against HCC 1395 cells. All the compounds were cytotoxic to HCC 1395 and DU 145 cancer cells but stigmasterol and canthin-6-one had the lowest IC₅₀ values of 7.2 and 0.42 μg/mL against HCC 1395 cells. Out of the chemical isolates, 10-methoxycanthin-6-one and canthin-6-one showed the strongest inhibition of the DU 145 cells (Kaigongi et al. 2020)